Impact of exposure time to harsh environments on physiology, mortality, and thermal comfort of day-old chickens in a simulated condition of transport

Abstract

The aim of this study was to assess the variation of physiological responses and mortality of day-old chicks subjected to different thermal conditions and exposure times during simulated transport. For this purpose, day-old chicks (n = 900) were used and subjected to simulated conditions of transport in a climate chamber. The experimental design was a completely randomized block design, with the structure of the treatments in a 3 × 3 factorial scheme (thermal ranges and time intervals) and each level of containers considered a block. The physiological variables used in this trial were body weight, respiratory rate, cloacal temperature, average surface temperature, and gene expression of heat shock protein (HSP70). Regarding body weight, a small variation was observed between treatments (P > 0.05). The animals subjected to the heat treatment exhibited respiratory rates above 100 movements per minute (P < 0.05), average cloacal temperatures above 44.7 °C, surface temperatures above the comfort zone (greater than 39.6 °C; P < 0.05), and increased gene expression of HSP70 (P < 0.001), especially after 3 initial hours of exposure. In addition, the heat treatment lead to increased mortality of the animals (over 6%). Also in the cold treatment, despite the absence of mortality, the animals showed hypothermia from 3 h of exposure, based on the results of the average surface (28 °C) and cloacal temperatures (39.6 °C; P < 0.05). In this way, the results imply that the effects of thermal stress caused by heat as well as by cold in a simulated transport condition are increased when traveling for more than 3 h, indicating a trend of rising mortality after long-term transportation of day-old chickens.

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The role of national problems in European air quality regulation: the process of amplification

Abstract

Recurring themes in the literature on European environmental policy-making is the leader–laggard spectrum and regulatory competition. European environmental policy is driven towards expansion because certain states take up leadership roles and manage to have their preferred regulatory solution adopted by the relevant European policy-making institution. During the policy process, leaders face 'laggards', states that do not favour ambitious regulation and drag their feet. The leader–laggard spectrum is volatile. States play different roles depending on the issue of interest, and over time their roles shift as well. This article investigates the role of relatively small-scale national events on the position of states on the spectrum. The regulatory competition involved in the leader–laggard spectrum may create an amplification effect of national problems: Through the efforts of the state afflicted by it, they acquire a European dimension they might otherwise not have had. They can cause member states to exhibit an extraordinary interest in a certain policy field and certain type of regulation for a brief period of time, shaping it considerably. After that, specific national problem has been solved or has blown over though they withdraw, leaving a gap for new contenders to fill. Yesterday's champions may be the laggards of tomorrow and vice versa. New champions bring their specific regulatory styles, their favourite solutions and their policy-making philosophy to bear on EU environmental regulation, exacerbating the already patchy character of this policy field.

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Focused CT for the evaluation of suspected appendicitis

Abstract

Purpose

To determine the diagnostic accuracy of focused appendiceal CT as a feasible alternative to the standard CT of the abdomen and pelvis (CT-AP) in patients with suspected acute appendicitis.

Methods

Retrospective review of 200 adults with suspected acute appendicitis between January and October 2016 were included in this study. Each patient underwent CT-AP with oral and intravenous (IV) contrast. A subset of axial images starting at the top of L4 vertebral body to the roof of the acetabula were obtained from each study which served as the focused appendiceal CT. After review of the focused CTs, the non-focused CT-AP scans were reviewed, each patient acting as their own control. Images were assessed for ability to identify the appendix, assess for appendicitis, or identify alternative diagnoses that could account for the presenting symptoms.

Results

Of 200 cases, the appendix was visualized in the focused CT in 191 patients. In nine studies, the appendix was not visualized in focused or standard CT-AP. Using focused CT, 42 cases were positive for acute appendicitis. This result was identical when reviewing standard CT-AP. Alternative diagnoses were present in 38 patients. Using focused CT, 14 of these were not fully covered but the readers were able to make the diagnoses confidently on the focused CTs. Only one patient had acute non-appendiceal pathology mostly outside of the field of view.

Conclusions

Focused appendiceal CT with IV and oral contrast in the setting of clinically suspected appendicitis is a suitable alternative to conventional CT-AP.

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Rural solid waste—characteristics and leachate pollution assessment for different precipitation levels, China

Abstract

Open dumping adversely affects the environment and remains the most widely used method for waste disposal in many developing rural areas in China. Information regarding the impact of rural solid waste (RSW) on the environment remains limited. The objectives of this study are to investigate the characteristics of RSW and the impact of different precipitation rates, and to evaluate the contamination potential of RSW using a leachate pollution index (LPI). The study showed that leachate concentration was significantly influenced by precipitation rates at the initial precipitation stages. Precipitation rates of 42.00 mm/day appeared to have the largest dilution effects. In contrast, the concentrations of leachate at rainfall rates of 24.00 mm/day and soaking were steady, and no similar trends were observed. The highest amounts of pollutants in leachate were the result of soaking. In the first week of our experiment, the LPI value for each rural area waste sample rapidly increased with rising precipitation rates from soaking to 42.00 mm/day. However, no significant change in LPI was observed thereafter (after 5 weeks) even with increasing precipitation rates. The values of chemical oxygen demand, biochemical oxygen demand, total nitrogen, and NH₃-N in the leachate after 10 weeks were 4.00, 7.34, 1.87, and 2.21 times higher, respectively, than those of the prescribed leachate quality standards in China. The results of our study suggest the following course of action for the three dump sites investigated: in Banqiao, given the size of the population and the size of the waste amount, landfill might be a suitable way for disposing of RSW. In Machen, building a standardized waste collection site would be an economical solution for reducing potential pollution risks. In Jiuduhe, increasing the transportation rate of solid waste might be an effective solution. The results of this study can help to improve the understanding of leachate pollution in Chinese rural areas.

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A review of parathyroid mass and patients with nonspecific complaints

Journal of International Medical Research, Ahead of Print.


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Multiple phosphorus acquisition strategies adopted by fine roots in low-fertility soils in Central Amazonia

Abstract

Background and aims

Ancient Amazon soils are characterised by low concentrations of soil phosphorus (P). Therefore, it is hypothesised that plants may invest a substantial proportion of their resources belowground to adjust their P-uptake strategies, including root morphological, physiological (phosphatase enzyme activities) and biotic (arbuscular mycorrhizal (AM) associations) adaptations. Since these strategies are energy demanding, we hypothesise that trade-offs between morphological traits and root phosphatase exudation and symbiotic associations would occur. Specifically, we expected that plants which invest in finer roots, and therefore have greater ability to explore large soil volumes, would have a high investment in physiological adaptations such as enhanced phosphatase production. In contrast, we expected that plants with predominantly thicker roots would invest more in symbiotic associations, in which carbon is traded for P acquired from AM fungal communities.

Methods

We collected absorptive roots (<2 mm diameter) from a lowland Central Amazon forest near Manaus, Brazil. We measured fine root diameter, specific root length (SRL), specific root area (SRA), root tissue density (RTD), root phosphatase activity (APase) and arbuscular mycorrhizal (AM) fungi colonisation.

Results

Root morphological traits were related to APase activity, with higher APase activity in roots with higher SRL and SRA but lower RTD. However, the degree of AM colonisation was not related to any measured root morphological trait.

Conclusions

Fine absorptive roots likely benefit from having low RTD, high SRL, SRA and APase exudation to acquire P efficiently. However, because AM colonisation was not related to root morphology, we suggest that investment in multiple P-uptake strategies is required for maintaining productivity in Central Amazon forests.

from Energy Ecology Environment Ambio via Terpsi Hori on Inoreader https://ift.tt/2tzD0NA

Endophytic community of Pb-Zn hyperaccumulator Arabis alpina and its role in host plants metal tolerance

Abstract

Aims

Endophytes benefit host plants by increasing biotic and abiotic stress tolerance. The aims of this study were to evaluate endophytic community (EC) of Arabis alpina, a Pb-Zn hyperaccumulator and investigate role of EC in host plants metal tolerance.

Methods

EC of A. alpina growing at Pb–Zn mining area was evaluated by Illumina MiSeq sequencing. Pot experiments were conducted for the role of EC in metal accumulation and tolerance of host.

Results

Fungal EC of shoots showed greater similarity to roots than to seeds; and Chao1 and Shannon indices for shoots and roots were significantly higher than for seeds. Inoculation of EC significantly improved host plants growth under multi-metal stress (p < 0.05, T test). The shoot length, root length and dry biomass of the treatment were improved when compared with the control. EC inoculation significantly altered accumulation of Pb, Cd and Zn in plant tissues. Particularly decreased the accumulation of Pb (p < 0.05) and Cd (p > 0.05) in the shoots of the treatment.

Conclusions

Hyperaccumulator A. alpina growing in metals contaminated soils was colonized by a diverse assemblage of endophytic fungi, and the EC played a key role in increasing host plants metal tolerance.

from Energy Ecology Environment Ambio via Terpsi Hori on Inoreader https://ift.tt/2GWQdYC

Growth and metal accumulation of young forest trees and understorey plants on contaminated topsoil: influence of subsoil and time

Abstract

Aims

The study investigated the growth and metal accumulation over time of young forest vegetation growing on metal-contaminated topsoil above either acidic or calcareous subsoil.

Methods

A 4-year model ecosystem experiment was performed under quasi-natural conditions. The heavy metal (HM) contaminated topsoil contained around 3000 mg/kg Zn, 600 Cu, 100 Pb, 9 Cd.

Results

Total biomass was 25.7% lower on the acidic than on the calcareous subsoil. The HM topsoil did not affect total understorey and Salix biomass, but decreased the growth of Populus, Betula and on the acidic subsoil also that of Picea. Leaf Cd and Zn concentrations were around 6 and 1000 mg/kg, respectively, in Populus and Salix on the HM topsoil, and 0.6 and 200 mg/kg in Picea and understorey. Leaf and wood HM concentrations, were lower in Populus and Salix on the calcareous than on the acidic subsoil. Temporal trends differed among the investigated metals. The HM-induced relative increases in leaf and wood metal concentrations were lower by at least an order of magnitude than in the respective soluble topsoil metal concentrations. Over the four years, Zn was increasingly accumulated in older twigs in Picea.

Conclusions

The selected native trees are suited for phytomanagement of HM-contaminated topsoils. Subsoil acidity is a relevant factor.

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Clinical Infectious Diseases

The Association of Antibiotic Stewardship With Fluoroquinolone Prescribing in Michigan Hospitals: A Multi-hospital Cohort Study Abstract Background Fluoroquinolones increase the risk of Clostridioides difficile infection and antibiotic resistance. Hospitals often use pre-prescription approval or prospective audit and feedback to target fluoroquinolone prescribing. Whether these strategies impact aggregate fluoroquinolone use is unknown. Methods This study is a 48-hospital, retrospective cohort of general-care, medical patients hospitalized with pneumonia or positive urine culture between December 2015–September 2017. Hospitals were surveyed on their use of pre-prescription approval and/or prospective audit and feedback to target fluoroquinolone prescribing during hospitalization (fluoroquinolone stewardship). After controlling for hospital clustering and patient factors, aggregate (inpatient and post-discharge) fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin) exposure was compared between hospitals with and without fluoroquinolone stewardship. Results There were 11 748 patients (6820 pneumonia; 4928 positive urine culture) included at 48 hospitals. All hospitals responded to the survey: 29.2% (14/48) reported using pre-prescription approval and/or prospective audit and feedback to target fluoroquinolone prescribing. After adjustment, fluoroquinolone stewardship was associated with fewer patients receiving a fluoroquinolone (37.1% vs 48.2%; P = .01) and fewer fluoroquinolone treatment days per 1000 patients (2282 vs 3096 days/1000 patients; P = .01), driven by lower inpatient prescribing. However, most (66.6%) fluoroquinolone treatment days occurred after discharge, and hospitals with fluoroquinolone stewardship had twice as many new fluoroquinolone starts after discharge as hospitals without (15.6% vs 8.4%; P = .003). Conclusions Hospital-based stewardship interventions targeting fluoroquinolone prescribing were associated with less fluoroquinolone prescribing during hospitalization, but not at discharge. To limit aggregate fluoroquinolone exposure, stewardship programs should target both inpatient and discharge prescribing.

Prevalence, Predictors, and Successful Treatment Outcomes of Xpert MTB/RIF–identified Rifampicin-resistant Tuberculosis in Post-conflict Eastern Democratic Republic of the Congo, 2012–2017: A Retrospective Province-Wide Cohort Study Abstract Background Multidrug-resistant tuberculosis (MDR-TB) jeopardizes global TB control. The prevalence and predictors of Rifampicin-resistant (RR) TB, a proxy for MDR-TB, and the treatment outcomes with standard and shortened regimens have not been assessed in post-conflict regions, such as the South Kivu province in the eastern Democratic Republic of the Congo (DRC). We aimed to fill this knowledge gap and to inform the DRC National TB Program. Methods of adults and children evaluated for pulmonary TB by sputum smear microscopy and Xpert MTB/RIF (Xpert) from February 2012 to June 2017. Multivariable logistic regression, Kaplan–Meier estimates, and multivariable Cox regression were used to assess independent predictors of RR-TB and treatment failure/death. Results Of 1535 patients Xpert-positive for TB, 11% had RR-TB. Independent predictors of RR-TB were a positive sputum smear (adjusted odds ratio [aOR] 2.42, 95% confidence interval [CI] 1.63–3.59), retreatment of TB (aOR 4.92, 95% CI 2.31–10.45), and one or more prior TB episodes (aOR 1.77 per episode, 95% CI 1.01–3.10). Over 45% of RR-TB patients had no prior TB history or treatment. The median time from Xpert diagnosis to RR-TB treatment initiation was 12 days (interquartile range 3–60.2). Cures were achieved in 30/36 (83%) and 84/114 (74%) of patients on 9- vs 20/24-month MDR-TB regimens, respectively (P = .06). Predictors of treatment failure/death were the absence of directly observed therapy (DOT; adjusted hazard ratio [aHR] 2.77, 95% CI 1.2–6.66) and any serious adverse drug event (aHR 4.28, 95% CI 1.88–9.71). Conclusions Favorable RR-TB cure rates are achievable in this post-conflict setting with a high RR-TB prevalence. An expanded Xpert scale-up; the prompt initiation of shorter, safer, highly effective MDR-TB regimens; and treatment adherence support are critically needed to optimize outcomes. The Association of Antibiotic Stewardship With Fluoroquinolone Prescribing in Michigan Hospitals: A Multi-hospital Cohort Study Abstract Background Fluoroquinolones increase the risk of Clostridioides difficile infection and antibiotic resistance. Hospitals often use pre-prescription approval or prospective audit and feedback to target fluoroquinolone prescribing. Whether these strategies impact aggregate fluoroquinolone use is unknown. Methods This study is a 48-hospital, retrospective cohort of general-care, medical patients hospitalized with pneumonia or positive urine culture between December 2015–September 2017. Hospitals were surveyed on their use of pre-prescription approval and/or prospective audit and feedback to target fluoroquinolone prescribing during hospitalization (fluoroquinolone stewardship). After controlling for hospital clustering and patient factors, aggregate (inpatient and post-discharge) fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin) exposure was compared between hospitals with and without fluoroquinolone stewardship. Results There were 11 748 patients (6820 pneumonia; 4928 positive urine culture) included at 48 hospitals. All hospitals responded to the survey: 29.2% (14/48) reported using pre-prescription approval and/or prospective audit and feedback to target fluoroquinolone prescribing. After adjustment, fluoroquinolone stewardship was associated with fewer patients receiving a fluoroquinolone (37.1% vs 48.2%; P = .01) and fewer fluoroquinolone treatment days per 1000 patients (2282 vs 3096 days/1000 patients; P = .01), driven by lower inpatient prescribing. However, most (66.6%) fluoroquinolone treatment days occurred after discharge, and hospitals with fluoroquinolone stewardship had twice as many new fluoroquinolone starts after discharge as hospitals without (15.6% vs 8.4%; P = .003). Conclusions Hospital-based stewardship interventions targeting fluoroquinolone prescribing were associated with less fluoroquinolone prescribing during hospitalization, but not at discharge. To limit aggregate fluoroquinolone exposure, stewardship programs should target both inpatient and discharge prescribing. Prevalence, Predictors, and Successful Treatment Outcomes of Xpert MTB/RIF–identified Rifampicin-resistant Tuberculosis in Post-conflict Eastern Democratic Republic of the Congo, 2012–2017: A Retrospective Province-Wide Cohort Study Abstract Background Multidrug-resistant tuberculosis (MDR-TB) jeopardizes global TB control. The prevalence and predictors of Rifampicin-resistant (RR) TB, a proxy for MDR-TB, and the treatment outcomes with standard and shortened regimens have not been assessed in post-conflict regions, such as the South Kivu province in the eastern Democratic Republic of the Congo (DRC). We aimed to fill this knowledge gap and to inform the DRC National TB Program. Methods of adults and children evaluated for pulmonary TB by sputum smear microscopy and Xpert MTB/RIF (Xpert) from February 2012 to June 2017. Multivariable logistic regression, Kaplan–Meier estimates, and multivariable Cox regression were used to assess independent predictors of RR-TB and treatment failure/death. Results Of 1535 patients Xpert-positive for TB, 11% had RR-TB. Independent predictors of RR-TB were a positive sputum smear (adjusted odds ratio [aOR] 2.42, 95% confidence interval [CI] 1.63–3.59), retreatment of TB (aOR 4.92, 95% CI 2.31–10.45), and one or more prior TB episodes (aOR 1.77 per episode, 95% CI 1.01–3.10). Over 45% of RR-TB patients had no prior TB history or treatment. The median time from Xpert diagnosis to RR-TB treatment initiation was 12 days (interquartile range 3–60.2). Cures were achieved in 30/36 (83%) and 84/114 (74%) of patients on 9- vs 20/24-month MDR-TB regimens, respectively (P = .06). Predictors of treatment failure/death were the absence of directly observed therapy (DOT; adjusted hazard ratio [aHR] 2.77, 95% CI 1.2–6.66) and any serious adverse drug event (aHR 4.28, 95% CI 1.88–9.71). Conclusions Favorable RR-TB cure rates are achievable in this post-conflict setting with a high RR-TB prevalence. An expanded Xpert scale-up; the prompt initiation of shorter, safer, highly effective MDR-TB regimens; and treatment adherence support are critically needed to optimize outcomes. Glycocalyx Breakdown is Associated with Severe Disease and Fatal Outcome in Plasmodium falciparum Malaria Abstract Background Interactions between the endothelium and infected erythrocytes, microvascular dysfunction and parasite sequestration play major roles in the pathogenesis of severe falciparum malaria. The glycocalyx is a carbohydrate-rich layer lining the endothelium mediating NO production and vascular homeostasis. The role of the glycocalyx in falciparum malaria and the association with disease severity is not known. Methods We prospectively enrolled Indonesian inpatients (≥18 years old) with severe (SM) or moderately-severe (MSM) falciparum malaria and healthy controls (HCs). Glycocalyx breakdown products were measured in enrolment samples of urine (glycosaminoglycans; dimethylmethylene blue [GAG-DMMB] and liquid chromatography-tandem mass spectrometry [GAG-MS] assays) and plasma (syndecan-1; ELISA), and related to vascular NO bioavailability (reactive hyperemia-peripheral arterial tonometry). Results A total of 129 subjects (SM=43, MSM=57, HC=29) were recruited. Syndecan-1 (µg/ml), GAG-DMMB and GAG-MS (g/mol creatinine) were increased in SM [median (range) 332.4 (85-3-1913), 3.16 (0.04-27.9) and 4.73 (2.02-27.13)] compared to MSM [99.1 (19.9-767.6), 1.28 (0.03-9.3) and 4.44 (1.19-13.87)], and HCs [48.9 (32.3-88.3), 0.11 (0.02-1.9) and 2.55 (0.73-10.19)]; P<0.001. In SM, GAG-DMMB and GAG-MS were increased in non-survivors (n=3) [median (IQR): 6.72 (3.80-27.87) and 12.15 (7.88-17.20)] compared to survivors n=39 [(3.10 (0.46-4.5) and 4.64 (2.02-15.20)]; P=0.03. Glycocalyx degradation was associated with parasite biomass in MSM (r=0.31, P=0.03 [syndecan-1]; r=0.48 [GAG-DMMB] and r=0.43 [GAG-MS], P<0.001), and SM patients (r=0.29, P=0.04, r=0.47; P=0.002 and r=0.33, P=0.04), and inversely associated with endothelial NO bioavailability. Conclusions Increased endothelial glycocalyx breakdown is associated with impaired vascular NO, severe disease and fatal outcome in adults with falciparum malaria, likely contributing to pathogenesis. Impact of rotavirus vaccine introduction in children less than 2 years of age presenting for medical care with diarrhea in rural Matlab, Bangladesh Abstract Background Following the conclusion of a Rotarix vaccine (HRV) cluster-randomized controlled trial (CRT) in Matlab, Bangladesh, HRV was included in Matlab's routine immunization program. We describe the population-level impact of programmatic rotavirus vaccination in Bangladesh in children <2 years of age Methods Interrupted time series were used to estimate the impact of HRVintroduction. Diarrheal surveillance collected between 2000 and 2014 within the two service delivery areas (icddr,b service area [ISA] and government service area [GSA]) of the Matlab Health and Demographic Surveillance System administered by icddr,b was used. Age-group specific incidence rates were calculated for both rotavirus-positive (RV+) and rotavirus-negative (RV-) diarrhea of any severity presenting to the hospital. Two models were used to assess impact within each service area: Model 1 used the pre-vaccine time period in all villages (HRV- and control-only) and Model 2 combined the pre-vaccine time period and the CRT time period using outcomes from control-only villages. Results Both models demonstrated a downward trend in RV+ diarrheal incidence in the ISA villages during 3.5 years of routine HRV use, though only Model 2 was statistically significant. Significant impact of HRV on RV+ diarrhea incidence in GSA villages was not observed in either model. Differences in population-level impact between the two delivery areas may be due to varied rotavirus vaccine coverage and presentation rate to the hospital. Conclusions This study provides initial evidence of the population-level impact of rotavirus vaccines in children <2 years of age in Matlab, Bangladesh. Further studies of rotavirus vaccine impact after nationwide introduction in Bangladesh are needed. Transmission-blocking effects of primaquine and methylene blue suggest P. falciparum gametocyte sterilisation rather than effects on sex ratio Abstract Gametocyte density and sex-ratio can predict the proportion of mosquitoes that become infected after feeding on blood of patients receiving non-gametocytocidal drugs. Because primaquine and methylene blue sterilize gametocytes before affecting their density and sex-ratio, mosquito feeding experiments are required to demonstrate their early transmission-blocking effects. Principal Controversies in Vaccine Safety in the United States Abstract Concerns about vaccine safety can lead to decreased acceptance of vaccines and resurgence of vaccine-preventable diseases. We summarize the key evidence on some of the main current vaccine safety controversies in the United States, including: 1) MMR vaccine and autism; 2) thimerosal, a mercury-based vaccine preservative, and the risk of neurodevelopmental disorders; 3) vaccine-induced Guillain-Barré Syndrome (GBS); 4) vaccine-induced autoimmune diseases; 5) safety of HPV vaccine; 6) aluminum adjuvant-induced autoimmune diseases and other disorders; and 7) too many vaccines given early in life predisposing children to health and developmental problems. A possible small increased risk of GBS following influenza vaccination has been identified, but the magnitude of the increase is less than the risk of GBS following influenza infection. Otherwise, the biological and epidemiologic evidence does not support any of the reviewed vaccine safety concerns. Insertion as resistance mechanism against integrase inhibitors in several retroviruses Birth Cohort Studies Assessing Norovirus Infection and Immunity in Young Children: A Review Abstract Globally, noroviruses are among the foremost causes of acute diarrheal disease, yet there are many unanswered questions on norovirus immunity, particularly following natural infection in young children during the first 2 years of life when the disease burden is highest. We conducted a literature review on birth cohort studies assessing norovirus infections in children from birth to early childhood. Data on infection, immunity, and risk factors are summarized from 10 community-based birth cohort studies conducted in low- and middle-income countries. Up to 90% of children experienced atleast one norovirus infection and up to 70% experienced norovirus-associated diarrhea, most often affecting children 6 months of age and older. Data from these studies help to fill critical knowledge gaps for vaccine development, yet study design and methodological differences limit comparison between studies, particularly for immunity and risk factors for disease. Considerations for conducting future birth cohort studies on norovirus are discussed. In the Literature Saddle Nose Deformity in an Immunosuppressed Patient Cover News Ebola's Curse: 2013–2016 Outbreak in West Africa By OldstoneMichael and OldstoneMadeleine. Elsevier, 2017. 126 pp. $89.95 (hardcover). ISBN: 9780128138885. Cost-effectiveness and Cost-utility of the Adherence Improving Self-management Strategy in Human Immunodeficiency Virus Care: A Trial-based Economic Evaluation Abstract Background Several promising human immunodeficiency virus (HIV) treatment adherence interventions have been identified, but data about their cost-effectiveness are lacking. This study examines the trial-based cost-effectiveness and cost-utility of the proven-effective Adherence Improving Self-Management Strategy (AIMS), from a societal perspective, with a 15-month time horizon. Methods Treatment-naive and treatment-experienced patients at risk for viral rebound were randomized to treatment as usual (TAU) or AIMS in a multicenter randomized controlled trial in the Netherlands. AIMS is a nurse-led, 1-on-1 self-management intervention incorporating feedback from electronic medication monitors, delivered during routine clinical visits. Main outcomes were costs per reduction in log10 viral load, treatment failure (2 consecutive detectable viral loads), and quality-adjusted life-years (QALYs). Results Two hundred twenty-three patients were randomized. From a societal perspective, AIMS was slightly more expensive than TAU but also more effective, resulting in an incremental cost-effectiveness ratio (ICER) of €549 per reduction in log10 viral load and €1659 per percentage decrease in treatment failure. In terms of QALYs, AIMS resulted in higher costs but more QALYs compared to TAU, which resulted in an ICER of €27759 per QALY gained. From a healthcare perspective, AIMS dominated TAU. Additional sensitivity analyses addressing key limitations of the base case analyses also suggested that AIMS dominates TAU. Conclusions Base case analyses suggests that over a period of 15 months, AIMS may be costlier, but also more effective than TAU. All additional analyses suggest that AIMS is cheaper and more effective than TAU. This trial-based economic evaluation confirms and complements a model-based economic evaluation with a lifetime horizon showing that AIMS is cost-effective. Clinical Trials Registration NCT01429142 First Human Case of Metacestode Infection Caused by Versteria sp. in a Kidney Transplant Recipient Abstract Cestodes are emerging agents of severe opportunistic infections among immunocompromised patients. We describe the first case of human infection, with the recently-proposed genus Versteria causing an invasive, tumor-like hepatic infection with regional and distant extension in a 53-year-old female kidney transplant recipient from Atlantic Canada. Doravirine/Lamivudine/Tenofovir Disoproxil Fumarate is Non-inferior to Efavirenz/Emtricitabine/Tenofovir Disoproxil Fumarate in Treatment-naive Adults With Human Immunodeficiency Virus–1 Infection: Week 48 Results of the DRIVE-AHEAD Trial Abstract Background Doravirine (DOR), a novel non-nucleoside reverse-transcriptase inhibitor (NNRTI), is active against wild-type Human Immunodeficiency Virus (HIV)-1 and the most common NNRTI-resistant variants, and has a favorable and unique in vitro resistance profile. Methods DRIVE-AHEAD is a phase 3, double-blind, non-inferiority trial. Antiretroviral treatment–naive adults with ≥1000 HIV-1 RNA copies/mL were randomized (1:1) to once-daily, fixed-dose DOR at 100 mg, lamivudine at 300 mg, and tenofovir disoproxil fumarate (TDF) at 300 mg (DOR/3TC/TDF) or to efavirenz at 600 mg, emtricitabine at 200 mg, and TDF at 300 mg (EFV/FTC/TDF) for 96 weeks. The primary efficacy endpoint was the proportion of participants with <50 HIV-1 RNA copies/mL at week 48 (Food and Drug Administration snapshot approach; non-inferiority margin 10%). Results Of the 734 participants randomized, 728 were treated (364 per group) and included in the analyses. At week 48, 84.3% (307/364) of DOR/3TC/TDF recipients and 80.8% (294/364) of EFV/FTC/TDF recipients achieved <50 HIV-1 RNA copies/mL (difference 3.5%, 95% CI, -2.0, 9.0). DOR/3TC/TDF recipients had significantly lower rates of dizziness (8.8% vs 37.1%), sleep disorders/disturbances (12.1% vs 25.2%), and altered sensorium (4.4% vs 8.2%) than EFV/FTC/TDF recipients. Mean changes in fasting low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) (-3.83 vs +13.26 mg/dL) were significantly different between DOR/3TC/TDF and EFV/FTC/TDF (−1.6 vs +8.7 mg/dL and −3.8 vs +13.3 mg/dL, respectively). Conclusions In HIV-1 treatment-naive adults, DOR/3TC/TDF demonstrated non-inferior efficacy to EFV/FTC/TDF at week 48 and was well tolerated, with significantly fewer neuropsychiatric events and minimal changes in LDL-C and non–HDL-C compared with EFV/FTC/TDF. Clinical Trials Registration NCT02403674 A 44-Year-Old Female With Overwhelming Sepsis sepsisaspleniaRPSA geneHowell-Jolly bodiesStreptococcus pneumonia Concurrent Seroprevalence of Antibodies to Toxoplasma gondii and Toxocara Species in the United States, 2011–2014 To the Editor—We report supplemental findings incorporating Toxoplasma gondii serology results from our study of risk factors for Toxocara seropositivity in the United States [1] using stored serum samples collected from the National Health and Nutrition Examination Survey (NHANES), 2011–2014. Whereas T. gondii is a protozoan parasite and Toxocara is an intestinal nematode, both share ingestion of contaminated soil as means of exposure in humans. Both parasites can contaminate soil when environmentally resistant T. gondii oocysts or Toxocara cati eggs are shed in the feces of infected cats [2, 3].

Hepatitis C Guidance 2018 Update: AASLD-IDSA Recommendations for Testing, Managing, and Treating Hepatitis C Virus Infection Abstract Recognizing the importance of timely guidance regarding the rapidly evolving field of hepatitis C management, the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) developed a web-based process for the expeditious formulation and dissemination of evidence-based recommendations. Launched in 2014, the hepatitis C virus (HCV) guidance website undergoes periodic updates as necessitated by availability of new therapeutic agents and/or research data. A major update was released electronically in September 2017, prompted primarily by approval of new direct-acting antiviral agents and expansion of the guidance's scope. This update summarizes the latest release of the HCV guidance and focuses on new or amended recommendations since the previous September 2015 print publication. The recommendations herein were developed by volunteer hepatology and infectious disease experts representing AASLD and IDSA and have been peer reviewed and approved by each society's governing board.

Functional Improvements Utilizing the Short Physical Performance Battery (SPPB) in the Elderly after Epidural Steroid Injections

Abstract

Purpose of Review

The treatment of debilitating pain and loss of function secondary to lumbar stenosis is in high demand with the aging patient population. Options, including epidural steroid injections (ESIs) and medication therapy, are limited and it is unclear if they provide any functional improvements. In this prospective study, we evaluate functional outcomes in older adults with symptomatic lumbar stenosis treated with ESIs compared to those managed with medications by introducing the Short Physical Performance Battery (SPPB). Our study was IRB-approved and included 16 patients, 68 to 83 years old, with symptomatic back and radicular leg pain secondary to lumbar stenosis. Patients could elect to undergo a lumbar ESI (n = 11) or be treated via medication management (n = 5). Numeric pain score, SPPB score, and adverse events were measured and compared at baseline and a 1-month follow-up visit.

Recent Findings

Statistically significant improvements were observed from baseline compared to the 1-month follow-up for total SPPB score in the injection group. Similar improvements in the injection group were observed for pain scores and the SPPB subcomponents such as the 4-m walk test, chair stand time, and balance score. Comparatively, no statistically significant improvements were observed in the medication group.

Summary

Lumbar ESIs improved objective physical capacity parameters and pain scores in elderly patients with symptomatic lumbar stenosis compared to medication management. In addition, the SPPB is an easy-to-use tool to measure changes in physical function in older adults and could easily be integrated into an outpatient pain clinic.

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Perioperative Considerations in the Management of Anticoagulation Therapy for Patients Undergoing Surgery

Abstract

Purpose of Review

As ambulatory surgery has become increasingly more common, the appropriate management of anticoagulation therapy in patients undergoing invasive procedures has become progressively more relevant to healthcare professionals. The purpose of this literature review is to provide an overview of current common anaticoagulants and their pharmacological properties and to evaluate recent relevant literature and bridging therapy and provide recommendations on risk-guided therapy.

Recent Findings

With the development of new drugs and the advancing study and practice of anticoagulation use, clinicians must keep up-to-date on the optimal management of patients requiring anticoagulation. NOACs and warfarin continue to be the mainstays of treatment, with varying timelines regarding when to hold administration of the different agents within the perioperative period.

Summary

There are numerous factors that are considered in patients with multiple comorbidities including the risk for stroke on long-term anticoagulation and risk for thromboembolism, particularly in the perioperative setting when certain medication regimens may be altered and/or briefly held. There is ongoing investigation whether certain NOACs have more efficacy or greater safety profiles, depending on the degree of surgical intervention.

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Ecotoxicological assessments of biochar additions to soil employing earthworm species Eisenia fetida and Lumbricus terrestris

Abstract

Biochar is the degradation-resistant product generated by the pyrolysis of organic materials and is produced for the intended use of land application in order to promote carbon sequestration and soil improvement. However, despite the many potential benefits biochar application offers, it is important to quantify any ecological impacts that may result from soil amendment in order to avoid potentially causing negative effects upon soil biota which are crucial in the many ecosystem services provided by soil. Any impacts on earthworms in particular are important to evaluate because of their pivotal role in organic matter breakdown, nutrient cycling and soil formation. In this study, we conducted a series of ecotoxicological assays to determine lethal and sublethal (avoidance, mass change and moisture content) effects of heavy biochar applications that reflect levels that may be used in soil restoration efforts. Two earthworm species, Eisenia fetida, an epigeic species, and Lumbricus terrestris, an anecic species, were utilised as test organisms. Two types of biochar, produced from wheat straw and rice husk feedstocks, respectively, were applied to OECD artificial soil and to a natural soil (Kettering loam) at rates of up to 20% w/w. The influence of biochar application on soil porewater chloride, fluoride and phosphate concentrations was also assessed. The biochar applications induced only a subtle level of avoidance behaviour while effects on survival over a 4-week exposure period were inconsistent. However, death and physical damage to some individual earthworms at high biochar application rates were observed, the mechanisms and processes leading to which should be investigated further. Earthworm development (mean mass change over time) proved to be a more sensitive measure, revealing negative effects on L. terrestris at 10% and 20% (w/w) wheat biochar applications in OECD soil and at 20% (w/w) applications of both biochars in Kettering loam. The moisture content of E. fetida remained remarkably consistent across all treatments (~ 82%), indicating that this is not a sensitive measure of effects. The high rates of biochar application resulted in increased chloride (2 to 3-fold) and phosphate (100-fold) concentrations in simulated soil porewaters, which has important implications for soil fertility and production but also for environmental management.

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Investigating the nexus among environmental pollution, economic growth, energy use, and foreign direct investment in 6 selected sub-Saharan African countries

Abstract

This research seeks to enhance the current literature by exploring the nexus among environmental contamination, economic growth, energy use, and foreign direct investment in 6 selected sub-Saharan African nations for a time of 34 years (1980–2014). By applying panel unit root (CADF and CIPS, cross-sectional independence test), panel cointegration (Pedroni and Kao cointegration test, panel PP, panel ADF), Hausman poolability test, and an auto-regressive distributed lag procedure in view of the pooled mean group estimation (ARDL/PMG), experimental findings disclose that alluding to the related probability values, the null hypothesis of cross-sectional independence for all variables is rejected because they are not stationary at levels but rather stationary at their first difference. The variables are altogether integrated at the same order I(1). Findings revealed that there is a confirmation of a bidirectional causality between energy use and CO₂ in the short-run and one-way causality running from energy use to CO₂ in the long run. There is additionally a significant positive outcome and unidirectional causality from CO₂ to foreign direct investment in the long run yet no causal relationship in the short run. An increase in energy use by 1% causes an increase in CO₂ by 49%. An increase in economic growth by 1% causes an increment in CO₂ by 16% and an increase in economic growth squared by 1% diminishes CO₂ by 46%. The positive and negative impacts of economic growth and its square approve the EKC theory. To guarantee sustainable economic development goal, more strict laws like sequestration ought to be worked out, use of sustainable power source ought to be stressed, and GDP ought to be multiplied to diminish CO₂ by the utilization of eco-technology for instance carbon capturing, to save lives and also to maintain a green environment.

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A review of parathyroid mass and patients with nonspecific complaints

Journal of International Medical Research, Ahead of Print.


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Correction to: Effects of Carbohydrate Mouth Rinse on Cycling Time Trial Performance: A Systematic Review and Meta-Analysis

Section 3.2, Fig. 2: The wording on the x-axis which previously read.

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Temperature and humidity index (THI)-induced rumen bacterial community changes in goats

Abstract

The rumen microbiome is thought to play an important role in maintaining normal gastrointestinal metabolism and nutrient absorption in ruminants. The present study was designed to investigate the effect of heat stress on the rumen microbiome of goats using 16S rRNA sequencing technology. Six female goats were randomly allocated into two control metabolic chambers: A and B (in which the temperature and humidity could be precisely controlled with a precision deviation of ± 0.5 °C and ± 5%, with three goats/chamber). Dynamic changes in the rumen bacterial community were detected under 16 gradually increasing temperature and humidity indexes (THIs). Heat stress had no significant effect on alpha diversity but affected the main phyla and genera of the goat rumen microbiota. With a deeper level of heat stress, the TH groups formed a distinct cluster that differed from that of the control check (CK) group. The dominant phylum transitioned from Firmicutes to Bacteroidetes, and co-exclusion occurred between these two phyla. With the increase in THI, the content of probiotics in the Lachnospiraceae_ND3007_group (P < 0.05) decreased, and the abundance of pathogenic bacteria, such as Erysipelotrichaceae_UCG-004 and Treponema_2, increased; however, the difference between the groups was not significant (P > 0.05). Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) was used to predict bacterial function, and we found that the ambient environment significantly affected the balance between carbohydrate and energy metabolism (P < 0.05). In conclusion, heat stress changed the composition of rumen microbes and affected metabolic function. This experiment provides a theoretical basis for exploring the effects of environmental factors on the rumen of goats.

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Effect of cation type in mixed Ca-Na systems on transport of sulfonamide antibiotics in saturated limestone porous media

Abstract

Retention and transport of sulfonamides (SAs) in subsurface can strongly affect groundwater quality. In this work, a range of laboratory batch sorption and column transport experiments were conducted to determine the effect of cation type in mixed Ca-Na systems on the retention and transport of two typical SAs, sulfadimethoxine (SDM) and sulfacetamide (SCA), in saturated limestone porous media. Column experimental data showed divalent cation Ca²⁺ played a more important role than monovalent cation Na⁺ in decreasing the transport of only SDM in co-cation systems in the saturated limestone media. Further, in the single-cation (i.e., including either Ca²⁺ or Na⁺) system, increasing ionic strength (IS) of either NaCl or CaCl₂ had little effect on SCA transport; however, increasing of IS of CaCl₂ promoted the retention of SDM in the saturated limestone porous media. This is mainly due to the cation bridging effect of Ca²⁺ on SDM and limestone. Overall, SDM showed much higher retention in the limestone columns than SCA, which can be attributed to the two SAs' different physicochemical properties. Moreover, limestone showed stronger ability to retain the two SAs than quartz sand. Findings in this study suggest that cation type and the concentration of certain electrolyte (e.g., CaCl₂) as well as medium type play an important role in controlling the environmental fate and transport of antibiotics.

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Combined use of biochar and zinc oxide nanoparticle foliar spray improved the plant growth and decreased the cadmium accumulation in rice ( Oryza sativa L.) plant

Abstract

The contamination of large areas of arable land with cadmium (Cd) is a serious concern worldwide and environmentally feasible amendments are necessary to minimize Cd accumulation in cereals such as rice (Oryza sativa L.). A pot study was, therefore, conducted to evaluate the efficiency of foliar spray of different levels (0, 50, 75, 100 mg/L) of zinc oxide nanoparticles (ZnO NPs) alone or combined with biochar (1.0% w/w) on Cd content in rice plants grown on an aged Cd-polluted soil. The results showed that ZnO NPs alone or combined with biochar improved the biomass and photosynthesis of rice plant. The ZnO NPs significantly diminished the Cd concentration and enhanced the Zn concentrations in shoots and roots either alone or in combination with biochar. Foliar spray of 100 mg/L ZnO NPs significantly diminished the Cd content in rice shoot and rice roots by 30% and 31%, respectively. The Cd concentrations in rice shoot and root diminished by 39% and 38% after 100 mg/L ZnO NPs combined with biochar, respectively. The ZnO NPs in combination with biochar increased the soil pH from 8.03 to 8.23 units. Soil AB-DTPA-extractable Cd significantly reduced with the amendments applied over the control. Foliar spray of ZnO NPs combined with biochar could be used to grow rice plants especially in areas where Cd concentration is high and Zn deficiency is high.

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A Reversible Liquid Organic Hydrogen Carrier System Based on Methanol‐Ethylenediamine and Ethylene Urea

A novel liquid organic hydrogen carrier (LOHC) system, with a high theoretical hydrogen capacity, based on the unpresented hydrogenation of ethylene urea to ethylenediamine and methanol, and its reverse dehydrogenative coupling, was established. For the dehydrogenation only a small amount of solvent is required. This system is rechargeable, as the H2‐rich compounds could be regenerated by hydrogenation of the resulting dehydrogenation mixture. Both directions for hydrogen loading and unloading were achieved using the same catalyst, under relatively mild conditions. Mechanistic studies reveal the likely pathway for H2‐lean compounds formation.

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Olefins and Vinyl Polar Monomers: Bridging the Gap for Next Generation Materials

The inherent differences in reactivity between activated and non‐activated alkenes prevents copolymerization using established polymer synthesis techniques. Research over the past 20 years has greatly advanced the copolymerization of polar vinyl monomers and olefins. This review highlights the challenges associated with conventional polymerization systems and evaluates the most relevant methods which have been developed to 'bridge the gap' between polar vinyl monomers and α‐olefins. We discuss advancements in heteroatom tolerant coordination‐insertion polymerizations, methods of controlling radical polymerizations to incorporate olefinic monomers, as well as combined approaches employing sequential polymerizations. Finally, we discuss state‐of‐the‐art stimuli responsive systems capable of facile switching between catalytic pathways and provide an outlook towards applications in which tailored copolymers are ideally suited.

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Franck‐Condon Blockade and Aggregation Modulated Conductance in Molecular Devices Using Aggregation‐Induced Emission Active Molecules

We report an effective modulation of the quantum transport in molecular junctions consisting aggregation‐induced emission (AIE) active molecules. Theoretical simulations based on combined density functional theory and rate‐equation method calculations show that the low‐bias conductance of the junction with a single tetraphenylethene (TPE) molecule can be completely suppressed by the strong electron‐vibration couplings, i. e. the Franck‐Condon blockade effect. It is mainly associated with the low energy vibration modes, which is also the origin of the fluorescence quenching of the AIE molecule in solution. We further found that the conductance of the junction can be lifted by restraining the internal motion of the TPE molecule by either the methyl substitution on the phenyl group or by the aggregation, a mechanism similar to the AIE process. The present work demonstrates the correlation between optical process of molecules and quantum transport in their junction, and thus open a new avenue for the application of AIE type molecules in molecular electronics and functional devices.

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Water Vapor does not Catalyze the Reaction between Methanol and OH Radicals

Recent works [Jara‐Toro et al., Angew. Chem. Int. Ed. 2017, 56, 2166 and PCCP 2018, 20, 27885] suggest that the rate coefficient of OH reactions with alcohols would increase by up to 2 times from dry to high humidity. This finding would have an impact on the budget of alcohols in the atmosphere and that it may explain differences in measured and modeled methanol concentrations. The results were based on a relative technique carried out in a small Teflon bag, which might suffer from wall reactions. We have re‐investigated this effect using a direct fluorescence probe of OH radicals, and no catalytic effect of H2O could be found. Experiments in a Teflon bag were also carried out, but we were not able to reproduce the results of Jara‐Toro et al. Further theoretical calculations show that the water‐mediated reactions have negligible rates compared to the bare reaction and that even though water molecules can lower the barriers of reactions, it cannot make up for the entropy cost.

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A High Affinity Fluorescent Catecholamine Sensor: Application to Monitoring Norepinephrine Exocytosis

A fluorescent sensor for catecholamines, NS510 is presented. The sensor is based on a quinolone fluorophore incorporating a boronic acid recognition element that gives it high affinity for catecholamines and a turn‐on response to norepinephrine. The sensor results in punctate staining of norepinephrine‐enriched chromaffin cells visualized using confocal microscopy indicating that it stains the norepinephrine in secretory vesicles. Amperometry in conjunction with TIRF microscopy demonstrates that the sensor can be used to observe destaining of individual chromaffin granules upon exocytosis. NS510 is the highest affinity fluorescent norepinephrine sensor currently available and can be used for measuring catecholamines in live‐cell assays.

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Highly selective, high capacity separation of o‐xylene from C8 aromatics by a switching adsorbent layered material

Adsorbent materials that exhibit high selectivity without sacrificing adsorption capacity can significantly reduce energy costs for industrial separation/purification processes and thus facilitate a transition away from energy‐intensive processes such as conventional distillation. Purification of the C8 aromatics (xylenes and ethylbenzene) is particularly challenging because of their similar physical properties. It is also relevant because of their industrial utility. In this context, physisorptive separation of C8 aromatics has long been suggested as an energy efficient solution but no physisorbent has yet combined high selectivity (>5) with high adsorption capacity (>50 wt%). Herein, we report a counterintuitive approach to the adsorptive separation of o‐xylene from other C8 aromatics by the study of a known nonporous layered material, [Co(bipy)2(NCS)2]n (sql‐1‐Co‐NCS). We observe that sql‐1‐Co‐NCS can reversibly switch to C8 aromatics loaded phases with different switching pressures and kinetics, manifesting benchmark o‐xylene selectivity (SOX/EB ~ 60) and high saturation capacity (> 80 wt%). Structural insight into the observed selectivity and capacity is gained via analysis of the crystal structures of C8 aromatics loaded phases.

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Excited state charge transfer in covalently functionalized MoS2 with zinc phthalocyanine donor‐acceptor hybrid

Functionalization of MoS2 is of paramount importance tailoring its properties towards optoelectronic applications and unlocking its full potential. Zinc phthalocyanine (ZnPc) carrying an 1,2‐dithiolane oxide linker was employed to functionalize MoS2 at defected sites located at the edges. The structure of ZnPc‐MoS2 was fully assessed by complementary spectroscopic, thermal and microscopy imaging techniques. An energy level diagram, to visualize different photochemical events in ZnPc‐MoS2 was established and revealed bi‐directional electron transfer leading to ZnPc•+‐MoS2•– charge separated state. Markedly, evidence of charge transfer in the hybrid was demonstrated using fluorescence spectroelectrochemistry. Systematic studies performed by femtosecond transient absorption revealed involvement of excitons generated in MoS2 in promoting charge transfer, while such charge transfer was also possible when ZnPc was excited, signifying their potentiality in light energy harvesting devices.

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Chemical syntheses and chemical genetics of carboxyl polyether ionophores: Recent highlights

A central goal of chemical genetics is to develop molecular probes that enable fundamental studies of cellular systems. In the hierarchy of bioactive molecules, the so‐called ionophore‐class occupies an unflattering position in the lower branches: with typical labels being "non‐specific" and "toxic". In fact, the mere possibility that a candidate molecule possesses "ionophore‐activity" typically prompts its removal from further studies; ionophores ‐ from a chemical genetics perspective ‐ are molecular outlaws. In stark contrast to this overall poor reputation of ionophores, synthetic chemistry owes some of its most amazing achievements to studies of ionophore natural products, in particular the carboxyl polyethers renowned for their intricate molecular structures. These compounds have for decades been academic battlegrounds where new synthetic methodology is tested and retrosynthetic tactics perfected. Herein, we review the most exciting recent advances in carboxyl polyether ionophore (CPI) synthesis and in addition discuss the bourgeoning field of CPI‐chemical biology.

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Nucleophilic aromatic substitution at benzene with powerful strontium hydride and alkyl complexes

The key to isolation of the first alkylstrontium complex is the synthesis of a strontium hydride complex that is stable towards ligand exchange reactions. This was achieved by using the superbulky ß‐diketiminate ligand DIPePBDI (CH[C(Me)N‐DIPeP]2, DIPeP =2,6‐diisopentylphenyl). Reaction of DIPePBDI‐H with Sr[N(SiMe3)2]2 gave (DIPePBDI)SrN(SiMe3)2 which was converted with PhSiH3 to [(DIPePBDI)SrH]2. Dissolved in C6D6, the Sr hydride complex is stable is up to 70 °C. At 60 °C, H‐D isotope exchange gave full conversion to [(DIPePBDI)SrD]2 and C6D5H. Since H‐D exchange with D2 is also facile, the strontium hydride complex is a catalyst for the deuteration of C6H6 by D2. Reaction of [(DIPePBDI)SrH]2 with ethylene gave [(DIPePBDI)SrEt]2. The high reactivity of this first alkylstrontium complex is demonstrated by facile ethylene polymerization and nucleophilic aromatic substitution with C6D6 giving alkylated aromatic products and (DIPePBDI)SrD]2¬, both processes which proceed at room temperature. DFT calculations illustrate that the latter Et‐D exchange with C6D6 likely involves the highly instable Meisenheimer anion C6D6Et‾ as an intermediate.

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Selective and efficient removal of fluoride from water by in‐situ engineered amyloid fibrils‐ZrO2 hybrid membranes

Effective and selective removal of fluoride from water systems is a pressing global issue for both drinking water and wastewater purification. Most of the present adsorbents exhibit inferior removal performance and low capacity, due to the intrinsic feature (light halogenide) of fluoride ions, so that developing new materials capable to remove both high and low concentrations of fluoride from water remains a challenge. This work reports a new strategy for efficient removal of fluoride from contaminated water streams, which relies on carbon hybrid membranes made of amyloid fibrils‐ZrO2 nanoparticles (<10 nm) nucleated in‐situ onto the amyloid fibrils surface via a chemical deposition process. These nanoparticles provide the ensued hybrids a remarkable affinity towards fluoride and very efficient removal performance when used in the form of membranes in combination with activated carbon to increase permeability. These hybrid membranes exhibit superior selectivity for fluoride against various competitive ions, with a distribution coefficient Kd as high as 6820 mL/g, exceeding commercial ion‐exchange resins (IRA‐900) by 180 times and outdoing the performance of most commercial carbon‐activated aluminum membranes. In both low (several mg/L) and highly (~200 mg/L) fluoride concentrations, representative of tap‐water and wastewater contamination regimes, the efficiency of the membrane exceeds 99.5% removal. Benchmark on real untreated municipal tap water (~2.8 mg/L) under continuous operating mode, indicates that ~1750 Kg water/m2 membrane can be treated while maintain water quality above WHO drinking threshold, and the saturated membranes can be regenerated and re‐used several times without decrease in performance. The selectivity of the membranes, their simple and affordable manufacturing and their high performance on real water sources, make this technology highly promising for mitigating the problem of fluoride water contamination worldwide

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Metal–Organic Frameworks with Target‐Specific Active Sites Switched by Photoresponsive Motifs: Efficient Adsorbents for Tailorable CO2 Capture

Smart adsorbents were fabricated by introducing target‐specific active sites (amines) into photoresponsive metal–organic frameworks (PMOFs). The cis/trans isomerization of azobenzene motifs trigged by UV/Vis light irradiation adjusts the electrostatic potential of amines significantly. This leads to exposure/shelter of amines and successful modulation of CO₂ adsorption on strong active sites, which is impossible to realize by traditional PMOFs.

Abstract

Photoresponsive metal–organic frameworks (PMOFs) are of interest for tailorable CO₂ adsorption. However, modulation of CO₂ adsorption on PMOFs is based on steric hindrance or structural change owing to weak interactions between CO₂ and active sites. It is challenging to fabricate PMOFs with strong but tailorable sites for CO₂ adsorption. Now, the construction of PMOFs with target‐specific (strong) active sites is achieved by introducing tetraethylenepentamine into azobenzene‐functionalized MOFs for tailorable CO₂ adsorption. Amines are specific active sites for CO₂, contributing to capture CO₂ selectively. Cis/trans isomerization of azobenzene motifs trigged by UV/Vis light adjusts the electrostatic potential of amines significantly, leading to exposure/shelter of amines and modulation of CO₂ adsorption on strong active sites. This system enables us to design adsorption processes for CO₂ capture from mixtures, which is impossible to realize by traditional PMOFs.

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Correlative Electrochemical Microscopy of Li‐Ion (De)intercalation at a Series of Individual LiMn2O4 Particles

Each one an individual! The electrochemistry of a series of LiMn₂O₄ battery cathode materials is investigated at the single particle level. A wide variety of distinctive characteristics are revealed that can be assigned to the structure and morphology of the same particle as observed by microscopy.

Abstract

The redox activity (Li‐ion intercalation/deintercalation) of a series of individual LiMn₂O₄ particles of known geometry and (nano)structure, within an array, is determined using a correlative electrochemical microscopy strategy. Cyclic voltammetry (current–voltage curve, I–E) and galvanostatic charge/discharge (voltage–time curve, E–t) are applied at the single particle level, using scanning electrochemical cell microscopy (SECCM), together with co‐location scanning electron microscopy that enables the corresponding particle size, morphology, crystallinity, and other factors to be visualized. This study identifies a wide spectrum of activity of nominally similar particles and highlights how subtle changes in particle form can greatly impact electrochemical properties. SECCM is well‐suited for assessing single particles and constitutes a combinatorial method that will enable the rational design and optimization of battery electrode materials.

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A Hybrid Anion for Ionic Liquid and Battery Electrolyte Applications: Half Triflamide, Half Carbonate

The better half: A hybrid imide anion consisting of a trifluorosulfonyl and a methylcarbonate group shows a unique coordination behaviour. Owing to the combination of electron‐withdrawing groups the new anion is less weakly coordinating than the symmetric TFSI salt. Reversible Na deposition and stripping was established in ethylene carbonate:propylene carbonate (EC:PC) electrolyte.

Abstract

The synthesis of a new imide type anion, methylcarbonate(trifluoromethylsulfonyl)imide (MCTFSI) is described and the physicochemical properties of its sodium and N‐butyl‐N‐methyl pyrrolidinium salts as well as structural information obtained by X‐ray diffraction studies of the sodium salt are discussed in terms of charge delocalisation, coordination chemistry and electrochemical behaviour with respect to the analogous imdides bis(trifluoromethanesulfonyl)imide (TFSI) and bis(fluorosulfonyl)imide (FSI). The insight obtained from studying the new anion informs and reemphasizes the concept of weakly coordinating anions and coordination chemistry in designing electrolyte salts.

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Phosphine‐Stabilized Diiododiborenes: Isolable Diborenes with Six Labile Bonds

The lability of B=B, B−P, and B–halide bonds is combined in the synthesis of the first diiododiborenes. In a series of reactivity tests, these diiododiborenes undergo cleavage of all six of their central bonds in different ways.

Abstract

The lability of B=B, B−P, and B–halide bonds is combined in the syntheses of the first diiododiborenes. In a series of reactivity tests, these diiododiborenes undergo cleavage of all six of their central bonds in different ways, leading to products of B=B hydrogenation and dihalogenation as well as halide exchange.

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Selectivity Switch in a Rhodium(II) Carbene Triggered Cyclopentannulation: Divergent Access to Three Polycyclic Indolines

Triple whammy: Effective regio‐ and diastereoselectivity control of a cyclopentannulation affording three polycyclic indolines from the same starting materials has been realized. Access to either the three products derives from a simple change of solvent and reaction temperature.

Abstract

A selectivity switch in a Rh^II/carbene‐triggered cyclopentannulation with catalytic InCl₃ is reported for the first time, affording both diastereomers of the fused spiroindolines and an unusual bridged tetracyclic indoline in high yields with excellent selectivities. Mechanistic studies indicate an intramolecular annulation of the indole with an in situ formed aminocyclopropane. The stepwise thermal conversions from the kinetic spiroindoline to the metastable bridged indoline, and then to the thermodynamic spiroindoline, involving a ring‐opening rearrangement of a cyclopentane, is crucial for selectivity control.

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Branched‐Selective Direct α‐Alkylation of Cyclic Ketones with Simple Alkenes

An intermolecular direct branched‐selective α‐alkylation of cyclic ketones has been achieved using simple alkenes as the alkylation agents. 7‐Azaindoline is employed as a bifunctional ligand to facilitate enamine formation and guide subsequent C−H activation with an iridium catalyst. This method offers a straightforward and byproduct‐free means to access ketones with β‐stereocenters.

Abstract

Herein, we describe an intermolecular direct branched‐selective α‐alkylation of cyclic ketones with simple alkenes as the alkylation agents. Through an enamine‐transition metal cooperative catalysis mode, the α‐alkylation is realized in an atom‐ and step‐economic manner with excellent branched selectivity for preparing β‐branched ketones. Employment of a pair of bulky Brønsted acid and base as additives is responsible for enhanced efficiency. Promising enantioselectivity (74 % ee) has been obtained. Experimental and computational mechanistic studies suggest that a pathway through alkene migratory insertion into the Ir−C bond followed by C−H reductive elimination is involved for the high branched selectivity.

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Spatial Isolation of Zeolitic Imidazole Frameworks‐Derived Cobalt Catalysts: From Nanoparticle, Atomic Cluster to Single Atom

The size effect of transition metal nanoparticles on electrocatalytic performance remains ambiguous especially when decreasing the size to atomic level. Herein, we report the spatial isolation of cobalt species at atomic scale through tuning zinc dopants content in predesigned bimetallic Zn/Co zeolitic imidazole frameworks (ZnCo‐ZIFs), affording the successful synthesis of nanoparticles, atomic clusters and single atoms of Co catalysts on N‐doped porous carbon. This novel synthetic strategy allows the investigation of size effect on electrochemical behaviours from nanometer to angstrom. Electrochemical results demonstrate that the single Co atomic catalyst manifests superior bifunctional ORR/OER activity, durability and reversibility for Zn‐air batteries in comparison with other counterparts and noble metal Pt/C+RuO2, which can be attributed to the isolated single Co atoms with high reactivity and stability. Our findings open up a new avenue to regulate the metal particle size and catalytic performance of metal‐organic framework derivatives at multiscale level.

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HOCl‐triggered amino or carboxyl uncaging platform and its application for imaging and drug design

The overproduction of hypochlorous acid (HOCl) is highly correlated with diseases such as atherosclerosis, rheumatoid arthritis and cancer. Whilst acting as a marker of these diseases, HOCl might also be used as an activator of prodrugs or drug delivery systems for the treatment of the corresponding disease, an area that is so far unexplored. In this work, a new platform has been developed that can be used to design and synthesize HOCl probes that integrate detection, imaging and therapeutic functions. The probes derived from this platform can be used to detect HOCl using both NIR emission and the naked eye in vitro, with high sensitivity and selectivity at ultralow concentrations (the detection limit is at the nM level). Basal levels of HOCl can be imaged in HL‐60 cells without special stimulation. Moreover, the probes provided by this platform can rapidly uncage amino or carboxyl groups from prodrugs during HOCl detection and imaging to realize a therapeutic effect. This platform thus provides new opportunities for the design of multifunctional probes that integrate detection, imaging and therapeutic functions.

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Perovskite Oxide‐Based Electrodes for High‐Performance Photoelectrochemical Water Splitting: A Review

Photoelectrochemical (PEC) water splitting is an attractive strategy for the large‐scale production of renewable hydrogen from water. Developing cost‐effective, active and stable semiconducting photoelectrodes is extremely important for achieving PEC water splitting with high solar‐to‐hydrogen efficiency. Perovskite oxides as a large family of semiconducting metal oxides are extensively investigated as electrodes in PEC water splitting owing to their abundance, high (photo)electrochemical stability, compositional and structural flexibility allowing the achievement of high electrocatalytic activity, superior sunlight absorption capability and precise control and tuning of band gaps and band edges. In this review, the research progress in the design, development, and application of perovskite oxides in PEC water splitting is summarized, with a special emphasis placed on understanding the relationship between the composition/structure and (photo)electrochemical activity.

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A phthalimidoalkanamide derived novel DNMT inhibitor enhanced radiosensitivity of A549 cells by inhibition of homologous recombination of DNA damage

Summary

Purpose To elucidate the radiosensitizing effect and underlying mechanism of a new kind of DNA methyltransferase (DNMT) inhibitor with biological availability. Methods A novel non-nucleoside compound, designated as MA-17, was recently derived from a phthalimido alkanamide structure. DNMT expressions were confirmed in cultured human lung cancer (A549) and normal astrocyte (NHA) cells, radiosensitivity was measured using clonogenic assay, and assays of cell cycle alteration, apoptosis, DNA damage repair, and differential gene expression were undertaken. Results MA-17 significantly radiosensitized A549 cells with a mean dose enhancement ratio (DER) of 1.43 at the surviving fraction of 0.2 (p < 0.05 by one-tailed ratio paired t-test). MA-17 did not affect normal astrocytes (mean DER_0.2, 1.016; p = 0.420). MA-17 demonstrated a mean half-life of 1.0 h in vivo and a relatively even distribution in various tissues. Pretreatment with MA-17 increased sub-G1 fractions and inhibited the repair of DNA double-strand breaks, which are induced by irradiation. We found that MA-17 also down-regulated DNA homologous recombination and the Fanconi anemia pathway (FANCA, BRCA1, and RAD51C) in A549 cells. This bioinformatics finding was confirmed in validation Western blot to evaluate the expression of vital proteins. Conclusions A novel phthalimido alkanamide derivative, a DNMT inhibitor, possessed both biostability and favorable and substantial radiosensitizing effects by augmenting apoptosis or inhibiting DNA damage repair.

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Japan’s Hayabusa2 craft touches down on asteroid Ryugu

Japan's Hayabusa2 craft touches down on asteroid Ryugu

Japan's Hayabusa2 craft touches down on asteroid Ryugu, Published online: 22 February 2019; doi:10.1038/d41586-019-00671-3

The mission team is now waiting to learn whether the probe collected a sample from the space rock.

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Japan’s Hayabusa2 craft touches down on asteroid Ryugu

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PaxeraHealth Launching Universal Image Sharing Platform at ECR 2019

PaxeraHealth will launch the PaxeraShare image sharing platform at the 2019 European Congress of Radiology (ECR) annual meeting, Feb. 27-March 3 in Vienna, Austria. PaxeraShare is a modern approach to image sharing and data access. The platform is designed using the latest HTML5 technology that requires no software installation. It enables recipients, whether they are physicians or patients, to instantly view the images and reports from any browser or smart device, regardless of the opera...

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A professional treatment table that meets all your needs

During the Dubai exhibition, customers from many countries were received, and many bosses who opened beauty shops hope to find a treatment table that is really suitable for their needs. They hope that this treatment table can meet the needs of different customers. The first is comfortable enough to bring the user a complete relaxation experience. Secondly, it is fully functional and can meet the various needs of the beautician while reducing the beautician's The burden; the third is the appea...

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Philips Launches Latest Iteration of IntelliSpace Cardiovascular at HIMSS 2019

Philips announced the launch of IntelliSpace Cardiovascular 4.1, its next-generation cardiovascular image and information management system. The latest version builds on the existing pediatric reporting capabilities, recognizing the important and unique nature of the pediatric environment. Clinicians can now complete their workflows more efficiently in a web browser, while integration with Philips Forcare enables the sharing of patient data between health systems and hospitals. New features a...

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Siemens Healthineers Demonstrates Artificial Intelligence, Healthcare Digitalization at HIMSS19

At the 2019 Healthcare Information and Management Systems Society (HIMSS) global conference and exhibition, Feb. 11-15 in Orlando, Fla., Siemens Healthineers will demonstrate how healthcare providers can benefit from digitalization, particularly in the form of artificial intelligence (AI). In addition to its greater digital services portfolio, Siemens Healthineers will showcase two AI-based applications, the AI-Pathway Companion and the AI-Rad Companion. The company will also present vario...

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Philips Earns FDA Clearance for DigitalDiagnost C90 DR System

Philips announced it has received 510(k) clearance from the U.S. Food and Drug Administration (FDA) to market the DigitalDiagnost C90, its newest premium digital radiography (DR) system. Designed to increase patient throughput and decrease the time to diagnosis, the Philips DigitalDiagnost C90 offers healthcare organizations a flexible and customizable imaging solution that helps to improve workflow and clinical outcomes, while adding economic value. X-ray is often the start of a patient's...

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MODUS ESWT SHOCK WAVE with BULT-INCOMPRESSOR

MODUS ESWT with INTERNAL COMPRESSOR; New Model High Frequency Radial Shock Wave Treatment System Supported with a internal compressor for portable use. Offers ready to Use various treatment packages guides the operator visual and written treatment explanations. New model has got the same aesthetics ,ergonomic,lightweight(300 gr) handpiece and it provides easy treatment options with a wide range of applicators and easy to hold feature.

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MODUS ED-SWT SHOCK WAVE

MODUS – ED SWT utilizes low-intensity extracorporeal shock waves, focusing on blood vessels and encouraging neovascularization in the penis shaft and crus. The low-intensity shock waves help relieve vascular deficiency, a common cause of erectile dysfunction.

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Synopsys Releases Simpleware ScanIP Medical Software for 3-D Printing

Smart technology company Synopsys recently announced the release of the Synopsys Simpleware ScanIP Medical edition for 3-D printing and visualization. This new version of Simpleware ScanIP comes with U.S. Food and Drug Administration (FDA) 510(k) clearance, and CE and ISO 13485:2016 certification as a medical device. According to the company, Simpleware ScanIP Medical is the ideal choice for those working with 3-D imaging to create medical devices for pre-clinical workflows such as implant...

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FDA Clears Ion Endoluminal Lung Biopsy System

The U.S. Food and Drug Administration (FDA) cleared the Ion endoluminal system from Intuitive Surgical Inc. to enable minimally invasive biopsy in the peripheral lung. Lung cancer is the world's leading cause of cancer deaths, according to Intuitive Surgical. Many suspicious lesions found in the lung may be small and difficult to access, which can make obtaining a diagnosis challenging. The Ion system uses an ultra-thin articulating robotic catheter that can move 180 degrees in all dire...

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MRI and Computer Modeling Reveals How Wrist Bones Move

In a just-published Journal of Biomechanics article1, the researchers proved a longtime assumption about individuals' right and left wrists, while also finding differences between wrists of males and females. These discoveries could help inform and guide future treatments. "If someone has dysfunction of the wrist, it really impacts their quality of life," said UC Davis Biomedical Engineering Graduate Group member and article first author Brent Foster, who also was selected for a prestigiou...

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Study Unveils Blueprint for Treating Radiation-Resistant Brain Tumor

Researchers at the University of Michigan recently searched for new brain tumor treatments by exploring the reasons why some patients with gliomas live remarkably longer than others. Results from the study using mice suggested that certain patients' tumor cells are less aggressive and much better at repairing DNA than others, but are difficult to kill with radiation. The researchers then showed that combining radiation therapy with cancer drugs designed to block DNA repair may be an effective...

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Philips Launches Zenition Mobile C-arm Platform

Philips announced the launch of Philips Zenition, its new mobile C-arm imaging platform. Mobile C-arms are X-ray systems that are brought into the operating room (OR) to provide live image guidance during a wide range of surgeries including orthopedic, trauma and vascular procedures. The Zenition mobile C-arm platform brings together innovations in image capture, image processing, ease-of-use and versatility pioneered on Philips' Azurion platform. Zenition allows hospitals to maximize OR perf...

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New Targeted Therapy for Recurrent Brain Tumors Implanted for First Time

University of Minnesota Health (M Health) is the first in the United States to begin offering GammaTile Therapy, a new approach to treating recurrent brain tumors. GammaTile Therapy is a U.S. Food and Drug Administration (FDA)-cleared, surgically targeted radiation therapy (STaRT) manufactured by GT Medical Technologies that is designed to delay tumor regrowth for patients with brain tumors. The first patient was treated by University of Minnesota physician Clark C. Chen, M.D., Ph.D., head...

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A relative risk assessment of the open burning of WEEE

Abstract

Waste electric and electronic equipment (WEEE) represents a potential secondary source of valuable materials, whose recovery is a growing business activity worldwide. In low-income countries, recycling is carried out under poorly controlled conditions resulting in severe environmental pollution. High concentrations of both metallic and organic pollutants have been confirmed in air, soil, water, and sediments in countries with informal recycling areas. The release of these contaminants into the environment presents a risk to the health of the exposed population that has been widely acknowledged but still needs to be quantified. The aim of this work was to evaluate the relative risk from inhalation associated with the open burning of different kinds of WEEE. The shrinking core model was applied to estimate the concentration of the metals which would be released into the environment during the incineration of different types of WEEE. In addition, the potential generation of dioxins during the same informal practice was estimated, based on the plastic content of the WEEE. The results provided for the first time a comparative analysis of the risk posed from the open burning of WEEE components, proposing a methodology to address the absolute risk assessment to workers from the informal recycling of WEEE.

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Enhanced adsorption of cationic Pb(II) and anionic Cr(VI) ions in aqueous solution by amino-modified nano-sized illite-smectite clay

Abstract

A raw illite-smectite mixed-layered clay (RI/S) was ground for preparing nano-sized I/S clay (NI/S) and subsequently amino-functionalized via grafting of 3-aminopropyltrithoxysilane (APTES) (NH₂-RI/S and NH₂-NI/S, respectively). The samples were characterized by particle size analysis, specific surface area measurement, X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and ²⁹Si nuclear magnetic resonance (²⁹Si NMR). Compared to RI/S, NI/S has a narrow particle size distribution and appears in a platelet-like morphology due to the disintegration/exfoliation of RI/S after grinding. Based on the ²⁹Si NMR spectra, the appearances of tri-silicate units indicate the chemically grafting of APTES molecules on NH₂-RI/S and NH₂-NI/S, respectively. NH₂-NI/S can adsorb greater amounts of Pb(II) cations and Cr(VI) anions rather than NH₂-RI/S since NH₂-NI/S grafts more amounts of amine groups (-NH₂). The isotherm data for adsorption of Pb(II) cations and Cr(VI) anions can be described by the Langmuir model at different temperatures (i.e., 10 °C, 30 °C, and 50 °C), respectively. The maximum adsorption amounts of Pb(II) cations and Cr(VI) anions onto NH₂-NI/S calculated by the Langmuir isotherm model are 131.23 mg/g and 36.91 mg/g at 50 °C, respectively. The adsorptions of Pb(II) cations and Cr(VI) anions onto NH₂-NI/S involve in the surface complexation of NI/S and amine groups.

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At Freedom’s Borderland: The Black Regulars and Masculinity at Fort Davis, Texas

Abstract

Archaeologies of military life have made little contribution to the study of Black regulars on the frontier. In part, this is the result of disciplinary boundaries separating scholars who study military history from those who study the African diaspora. Other problems include the nature of military movements and the nature of military record keeping. In this article, ceramic materials from an 1870s deposit associated with Black enlisted men at Fort Davis, Texas, are discussed to demonstrate how material evidence provides insights into the ambitions, experiences, and actions of soldiers, in their status as freedmen and citizens, as they navigated the colonial structure of a western fort.

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Biosorption of glycerol impurities from biodiesel production onto electrospun chitosan-based nanofibers: equilibrium and thermodynamic evaluations

Abstract

The increase in biodiesel production has been leading to an excess amount of crude glycerol and, consequently, serious environmental issues. For this reason, electrospun chitosan-based nanofibers (CB-EN), composed by chitosan and poly(ethylene oxide) (PEO), were synthesized to apply in the biosorption of impurities from industrial glycerol. To evaluate the biosorption efficiency, the chitosan-based nanofiber was compared to other chitosan-based biosorbents (chitosan biopolymeric film and chitosan powder). The equilibrium and thermodynamic studies were successfully performed to comprehend the interaction mechanisms through the biosorption of glycerol pigments onto electrospun chitosan-based nanofibers. The temperature effect was evaluated by experimental equilibrium curves. Freundlich and BET models were used to estimate isotherm parameters. Gibbs free energy change, enthalpy change, entropy change, and isosteric heat of biosorption were quantified. The equilibrium curves showed that the highest equilibrium relative adsorption (340.7 g⁻¹) was reached at 60 °C. The BET model was the most suitable to represent the equilibrium behavior. The thermodynamic parameters indicated that the biosorption was spontaneous, exothermic, random, and energetic heterogeneous. Therefore, this work developed a green and efficient alternative to refine industrial glycerol.

Graphical abstract

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[ASAP] Experimental Evidence for pa-Driven Asynchronicity in C–H Activation by a Terminal Co(III)–Oxo Complex

Journal of the American Chemical Society

DOI: 10.1021/jacs.8b13490

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[ASAP] Cobalt in Nitrogen-Doped Graphene as Single-Atom Catalyst for High-Sulfur Content Lithium–Sulfur Batteries

Journal of the American Chemical Society

DOI: 10.1021/jacs.8b12973

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[ASAP] Resonance Theory Reboot

Journal of the American Chemical Society

DOI: 10.1021/jacs.8b12336

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