Designable electron transport features in one-dimensional arrays of metallic nanoparticles: Monte Carlo study of the relation between shape and transport

We study the current and shot noise in a linear array of metallic nanoparticles taking explicitly into consideration their discrete electronic spectra. Phonon assisted tunneling and dissipative effects on single nanoparticles are incorporated as well. The capacitance matrix which determines the classical Coulomb interaction within the capacitance model is calculated numerically from a realistic geometry. A Monte Carlo algorithm which self-adapts to the size of the system allows us to simulate the single-electron transport properties within a semiclassical framework. We present several effects that are related to the geometry and the one-electron level spacing like e.g. a negative differential conductance (NDC) effect. Consequently these effects are designable by the choice of the size and arrangement of the nanoparticles.Comment: 13 pages, 12 figure

Community Case Management of Fever Due to Malaria and Pneumonia in Children Under Five in Zambia: A Cluster Randomized Controlled Trial

In a cluster randomized trial, Kojo Yeboah-Antwi and colleagues find that integrated management of malaria and pneumonia in children under five by community health workers is both feasible and effective. BACKGROUND. Pneumonia and malaria, two of the leading causes of morbidity and mortality among children under five in Zambia, often have overlapping clinical manifestations. Zambia is piloting the use of artemether-lumefantrine (AL) by community health workers (CHWs) to treat uncomplicated malaria. Valid concerns about potential overuse of AL could be addressed by the use of malaria rapid diagnostics employed at the community level. Currently, CHWs in Zambia evaluate and treat children with suspected malaria in rural areas, but they refer children with suspected pneumonia to the nearest health facility. This study was designed to assess the effectiveness and feasibility of using CHWs to manage nonsevere pneumonia and uncomplicated malaria with the aid of rapid diagnostic tests (RDTs). METHODS AND FINDINGS. Community health posts staffed by CHWs were matched and randomly allocated to intervention and control arms. Children between the ages of 6 months and 5 years were managed according to the study protocol, as follows. Intervention CHWs performed RDTs, treated test-positive children with AL, and treated those with nonsevere pneumonia (increased respiratory rate) with amoxicillin. Control CHWs did not perform RDTs, treated all febrile children with AL, and referred those with signs of pneumonia to the health facility, as per Ministry of Health policy. The primary outcomes were the use of AL in children with fever and early and appropriate treatment with antibiotics for nonsevere pneumonia. A total of 3,125 children with fever and/or difficult/fast breathing were managed over a 12-month period. In the intervention arm, 27.5% (265/963) of children with fever received AL compared to 99.1% (2066/2084) of control children (risk ratio 0.23, 95% confidence interval 0.14–0.38). For children classified with nonsevere pneumonia, 68.2% (247/362) in the intervention arm and 13.3% (22/203) in the control arm received early and appropriate treatment (risk ratio 5.32, 95% confidence interval 2.19–8.94). There were two deaths in the intervention and one in the control arm. CONCLUSIONS. The potential for CHWs to use RDTs, AL, and amoxicillin to manage both malaria and pneumonia at the community level is promising and might reduce overuse of AL, as well as provide early and appropriate treatment to children with nonsevere pneumonia.United States Agency for International Development (GHSA-00-00020-00) with Boston University; President's Malaria Initiativ

A rapid landscape review of postpartum anaemia measurement: challenges and opportunities

BACKGROUND: Anaemia is a reduction in haemoglobin concentration below a threshold, resulting from various factors including severe blood loss during and after childbirth. Symptoms of anaemia include fatigue and weakness, among others, affecting health and quality of life. Anaemic pregnant women have an increased risk of premature delivery, a low-birthweight infant, and postpartum depression. They are also more likely to have anaemia in the postpartum period which can lead to an ongoing condition and affect subsequent pregnancies. In 2019 nearly 37% of pregnant women globally had anaemia, and estimates suggest that 50-80% of postpartum women in low- and middle-income countries have anaemia, but currently there is no standard measurement or classification for postpartum anaemia. METHODS: A rapid landscape review was conducted to identify and characterize postpartum anaemia measurement searching references within three published systematic reviews of anaemia, including studies published between 2012 and 2021. We then conducted a new search for relevant literature from February 2021 to April 2022 in EMBASE and MEDLINE using a similar search strategy as used in the published reviews. RESULTS: In total, we identified 53 relevant studies. The timing of haemoglobin measurement ranged from within the immediate postpartum period to over 6 weeks. The thresholds used to diagnose anaemia in postpartum women varied considerably, with < 120, < 110, < 100 and < 80 g/L the most frequently reported. Other laboratory results frequently reported included ferritin and transferrin receptor. Clinical outcomes reported in 32 out of 53 studies included postpartum depression, quality of life, and fatigue. Haemoglobin measurements were performed in a laboratory, although it is unclear from the studies if venous samples and automatic analysers were used in all cases. CONCLUSIONS: This review demonstrates the need for improving postpartum anaemia measurement given the variability observed in published measures. With the high prevalence of anaemia, the relatively simple treatment for non-severe cases of iron deficiency anaemia, and its importance to public health with multi-generational effects, it is crucial to develop common measures for women in the postpartum period and promote rapid uptake and reporting

Service user and caregiver involvement in mental health system strengthening in low- and middle-income countries: a cross-country qualitative study

The aims of this paper are to: (i) explore the experiences of involvement of mental health service users, their caregivers, mental health centre heads and policy makers in mental health system strengthening in three low- and middle-income countries (LMICs) (Ethiopia, Nepal and Nigeria); (ii) analyse the potential benefits and barriers of such involvement; and (iii) identify strategies required to achieve greater service user and caregiver participation. A cross-country qualitative study was conducted, interviewing 83 stakeholders of mental health services. Our analysis showed that service user and caregiver involvement in the health system strengthening process was an alien concept for most participants. They reported very limited access to direct participation. Stigma and poverty were described as the main barriers for involvement. Several strategies were identified by participants to overcome existing hurdles to facilitate service user and caregiver involvement in the mental health system strengthening process, such as support to access treatment, mental health promotion and empowerment of service users. This study suggests that capacity building for service users, and strengthening of user groups would equip them to contribute meaningfully to policy development from informed perspectives. Involvement of service users and their caregivers in mental health decision-making is still in its infancy in LMICs. Effective strategies are required to overcome existing barriers, for example making funding more widely available for Ph.D. studies in participatory research with service users and caregivers to develop, implement and evaluate approaches to involvement that are locally and culturally acceptable in LMICs

Effectiveness of community outreach HIV prevention programs in Vietnam: A mixed methods evaluation

Background In 2014, Vietnam was the first Southeast Asian country to commit to achieving the World Health Organization’s 90–90-90 global HIV targets (90% know their HIV status, 90% on sustained treatment, and 90% virally suppressed) by 2020. This pledge represented further confirmation of Vietnam’s efforts to respond to the HIV epidemic, one feature of which has been close collaboration with the U.S. President’s Emergency Plan for AIDS Relief (PEPFAR). Starting in 2004, PEPFAR supported community outreach programs targeting high-risk populations (people who inject drugs, men who have sex with men, and sex workers). To provide early evidence on program impact, in 2007–2008 we conducted a nationwide evaluation of PEPFAR-supported outreach programs in Vietnam. The evaluation focused on assessing program effect on HIV knowledge, high-risk behaviors, and HIV testing among high-risk populations—results relevant to Vietnam’s push to meet global HIV goals. Methods We used a mixed-methods cross-sectional evaluation design. Data collection encompassed a quantitative survey of 2199 individuals, supplemented by 125 in-depth interviews. Participants were members of high-risk populations who reported recent contact with an outreach worker (intervention group) or no recent contact (comparison group). We assessed differences in HIV knowledge, risky behaviors, and HIV testing between groups, and between high-risk populations. Results Intervention participants knew significantly more about transmission, prevention, and treatment than comparison participants. We found low levels of injection drug-use-related risk behaviors and little evidence of program impact on such behaviors. In contrast, a significantly smaller proportion of intervention than comparison participants reported risky sexual behaviors generally and within each high-risk population. Intervention participants were also more likely to have undergone HIV testing (76.1% vs. 47.0%, p \u3c 0.0001) and to have received pre-test (78.0% vs. 33.7%, p \u3c 0.0001) and post-test counseling (80.9% vs. 60.5%, p \u3c 0.0001). Interviews supported evidence of high impact of outreach among all high-risk populations. Conclusions Outreach programs appear to have reduced risky sexual behaviors and increased use of HIV testing services among high-risk populations in Vietnam. These programs can play a key role in reducing gaps in the HIV care cascade, achieving the global 90–90-90 goals, and creating an AIDS-free generation

Trace-gas metabolic versatility of the facultative methanotroph Methylocella silvestris

The climate-active gas methane is generated both by biological processes and by thermogenic decomposition of fossil organic material, which forms methane and short-chain alkanes, principally ethane, propane and butane1, 2. In addition to natural sources, environments are exposed to anthropogenic inputs of all these gases from oil and gas extraction and distribution. The gases provide carbon and/or energy for a diverse range of microorganisms that can metabolize them in both anoxic3 and oxic zones. Aerobic methanotrophs, which can assimilate methane, have been considered to be entirely distinct from utilizers of short-chain alkanes, and studies of environments exposed to mixtures of methane and multi-carbon alkanes have assumed that disparate groups of microorganisms are responsible for the metabolism of these gases. Here we describe the mechanism by which a single bacterial strain, Methylocella silvestris, can use methane or propane as a carbon and energy source, documenting a methanotroph that can utilize a short-chain alkane as an alternative to methane. Furthermore, during growth on a mixture of these gases, efficient consumption of both gases occurred at the same time. Two soluble di-iron centre monooxygenase (SDIMO) gene clusters were identified and were found to be differentially expressed during bacterial growth on these gases, although both were required for efficient propane utilization. This report of a methanotroph expressing an additional SDIMO that seems to be uniquely involved in short-chain alkane metabolism suggests that such metabolic flexibility may be important in many environments where methane and short-chain alkanes co-occur

Breast milk and in utero transmission of HIV-1 select for envelope variants with unique molecular signatures

Additional file 5: Figure S5. Representative CD4 infectivity curves using Affinofile cells for IUT (top) and BMT (bottom) maternal–infant pairs. Affinofile cells were induced to generate a 100-fold range of CD4 surface density (ABS/cell) and infected with 2000 IU pseudotyped virus. Percent infection was measured as the percent luciferase relative to infected and maximally induced Affinofile cells. Data shown are representative curves among 3–4 experimental replicates

Eff ectiveness of 4% chlorhexidine umbilical cord care on neonatal mortality in Southern Province, Zambia (ZamCAT): a cluster-randomised controlled trial

Background Chlorhexidine umbilical cord washes reduce neonatal mortality in south Asian populations with high neonatal mortality rates and predominantly home-based deliveries. No data exist for sub-Saharan African populations with lower neonatal mortality rates or mostly facility-based deliveries. We compared the eff ect of chlorhexidine with dry cord care on neonatal mortality rates in Zambia. Methods We undertook a cluster-randomised controlled trial in Southern Province, Zambia, with 90 health facilitybased clusters. We enrolled women who were in their second or third trimester of pregnancy, aged at least 15 years, and who would remain in the catchment area for follow-up of 28 days post-partum. Newborn babies received clean dry cord care (control) or topical application of 10 mL of a 4% chlorhexidine solution once per day until 3 days after cord drop (intervention), according to cluster assignment. We used stratifi ed, restricted randomisation to divide clusters into urban or two rural groups (located <40 km or ≥40 km to referral facility), and randomly assigned clusters (1:1) to use intervention (n=45) or control treatment (n=45). Sites, participants, and fi eld monitors were aware of their study assignment. The primary outcomes were all-cause neonatal mortality within 28 days post-partum and all-cause neonatal mortality within 28 days post-partum among babies who survived the fi rst 24 h of life. Analysis was by intention to treat. Neonatal mortality rate was compared with generalised estimating equations. This study is registered at ClinicalTrials.gov (NCT01241318). Findings From Feb 15, 2011, to Jan 30, 2013, we screened 42 356 pregnant women and enrolled 39 679 women (mean 436·2 per cluster [SD 65·3]), who had 37 856 livebirths and 723 stillbirths; 63·8% of deliveries were facility-based. Of livebirths, 18 450 (99·7%) newborn babies in the chlorhexidine group and 19 308 (99·8%) newborn babies in the dry cord care group were followed up to day 28 or death. 16 660 (90·0%) infants in the chlorhexidine group had chlorhexidine applied within 24 h of birth. We found no signifi cant diff erence in neonatal mortality rate between the chlorhexidine group (15·2 deaths per 1000 livebirths) and the dry cord care group (13·6 deaths per 1000 livebirths; risk ratio [RR] 1·12, 95% CI 0·88–1·44). Eliminating day 0 deaths yielded similar fi ndings (RR 1·12, 95% CI 0·86–1·47). Interpretation Despite substantial reductions previously reported in south Asia, chlorhexidine cord applications did not signifi cantly reduce neonatal mortality rates in Zambia. Chlorhexidine cord applications do not seem to provide clear benefi ts for newborn babies in settings with predominantly facility-based deliveries and lower (<30 deaths per 1000 livebirths) neonatal mortality rates

The shapes of elongating gastruloids are consistent with convergent extension driven by a combination of active cell crawling and differential adhesion.

Gastruloids have emerged as highly useful in vitro models of mammalian gastrulation. One of the most striking features of 3D gastruloids is their elongation, which mimics the extension of the embryonic anterior-posterior axis. Although axis extension is crucial for development, the underlying mechanism has not been fully elucidated in mammalian species. Gastruloids provide an opportunity to study this morphogenic process in vitro. Here, we measure and quantify the shapes of elongating gastruloids and show, by Cellular Potts model simulations based on a novel, optimized algorithm, that convergent extension, driven by a combination of active cell crawling and differential adhesion can explain the observed shapes. We reveal that differential adhesion alone is insufficient and also directly observe hallmarks of convergent extension by time-lapse imaging of gastruloids. Finally, we show that gastruloid elongation can be abrogated by inhibition of the Rho kinase pathway, which is involved in convergent extension in vivo. All in all, our study demonstrates, how gastruloids can be used to elucidate morphogenic processes in embryonic development

ETV2 upregulation marks the specification of early cardiomyocytes and endothelial cells during co-differentiation

Biological and Soft Matter Physic