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Understanding and controlling charge and energy flow in state-of-the-art semiconductor quantum wells has enabled high-efficiency optoelectronic devices. Two-dimensional (2D) Ruddlesden-Popper perovskites are solution-processed quantum wells wherein the band gap can be tuned by varying the perovskite-layer thickness, which modulates the effective electron-hole confinement. We report that, counterintuitive to classical quantum-confined systems where photogenerated electrons and holes are strongly bound by Coulomb interactions or excitons, the photophysics of thin films made of Ruddlesden-Popper perovskites with a thickness exceeding two perovskite-crystal units (>1.3 nanometers) is dominated by lower-energy states associated with the local intrinsic electronic structure of the edges of the perovskite layers. These states provide a direct pathway for dissociating excitons into longer-lived free carriers that substantially improve the performance of optoelectronic devices.

A study of single grains of lead halide perovskite reveals the presence of both excitons and free charge carriers. The nature of charge carriers in methylammonium lead iodide perovskites (MAPbI 3 ) at room temperature is still a matter of considerable debate 1 , 2 , 3 . Here, we demonstrate that within single grains of MAPbI 3 , strong spatial heterogeneities on the nanometre length scale are present and associated with simultaneous free-carrier and exciton populations. These heterogeneous populations, hidden in ensemble measurements, have a signature of spatially resolved relaxation dynamics for above-bandgap photoexcitation. Using spectrally resolved transient absorption microscopy, we directly observe both red- and blueshifts of the band-edge absorption across individual grains due to a dynamic Stark shift and screening of excitonic transitions by hot carriers. These observations help address a long-standing debate on the identity of the charge carriers, showing that both excitons and free carriers coexist, but are spatially segregated on the length scale of hundreds of nanometres.

Among high-risk patients undergoing angiography, there was no benefit of intravenous sodium bicarbonate over sodium chloride or of oral acetylcysteine over placebo for the prevention of death, dialysis, or contrast-associated acute kidney injury.

To contain multidrug-resistant Plasmodium falciparum, malaria elimination in the Greater Mekong subregion needs to be accelerated while current antimalarials remain effective. We evaluated the safety, effectiveness, and potential resistance selection of dihydroartemisinin–piperaquine mass drug administration (MDA) in a region with artemisinin resistance in Myanmar. We did a cluster-randomised controlled trial in rural community clusters in Kayin (Karen) state in southeast Myanmar. Malaria prevalence was assessed using ultrasensitive quantitative PCR (uPCR) in villages that were operationally suitable for MDA (villages with community willingness, no other malaria control campaigns, and a population of 50–1200). Villages were eligible to participate if the prevalence of malaria (all species) in adults was greater than 30% or P falciparum prevalence was greater than 10% (or both). Contiguous villages were combined into clusters. Eligible clusters were paired based on P falciparum prevalence (estimates within 10%) and proximity. Community health workers provided routine malaria case management and distributed long-lasting insecticidal bed-nets (LLINs) in all clusters. Randomisation of clusters (1:1) to the MDA intervention group or control group was by public coin-flip. Group allocations were not concealed. Three MDA rounds (3 days of supervised dihydroartemisinin–piperaquine [target total dose 7 mg/kg dihydroartemisinin and 55 mg/kg piperaquine] and single low-dose primaquine [target dose 0·25 mg base per kg]) were delivered to intervention clusters. Parasitaemia prevalence was assessed at 3, 5, 10, 15, 21, 27, and 33 months. The primary outcomes were P falciparum prevalence at months 3 and 10. All clusters were included in the primary analysis. Adverse events were monitored from the first MDA dose until 1 month after the final dose, or until resolution of any adverse event occurring during follow-up. This trial is registered with ClinicalTrials.gov, NCT01872702. Baseline uPCR malaria surveys were done in January, 2015, in 43 villages that were operationally suitable for MDA (2671 individuals). 18 villages met the eligibility criteria. Three villages in close proximity were combined into one cluster because a border between them could not be defined. This gave a total of 16 clusters in eight pairs. In the intervention clusters, MDA was delivered from March 4 to March 17, from March 30 to April 10, and from April 27 to May 10, 2015. The weighted mean absolute difference in P falciparum prevalence in the MDA group relative to the control group was −10·6% (95% CI −15·1 to −6·1; p=0·0008) at month 3 and −4·5% (−10·9 to 1·9; p=0·14) at month 10. At month 3, the weighted P falciparum prevalence was 1·4% (0·6 to 3·6; 12 of 747) in the MDA group and 10·6% (7·0 to 15·6; 56 of 485) in the control group. Corresponding prevalences at month 10 were 3·2% (1·5 to 6·8; 34 of 1013) and 5·8% (2·5 to 12·9; 33 of 515). Adverse events were reported for 151 (3·6%) of 4173 treated individuals. The most common adverse events were dizziness (n=109) and rash or itching (n=20). No treatment-related deaths occurred. In this low-transmission setting, the substantial reduction in P falciparum prevalence resulting from support of community case management was accelerated by MDA. In addition to supporting community health worker case management and LLIN distribution, malaria elimination programmes should consider using MDA to reduce P falciparum prevalence rapidly in foci of higher transmission. The Global Fund to Fight AIDS, Tuberculosis and Malaria.

Aim: A variety of anthropometric techniques have been proposed to determine the correct vertical dimension of occlusion. However, none have reported correlating thumb length (TL) with vertical dimension at rest (VDR). This study aimed to correlate the VDR to measurements of the thumb in a multi-national, multi-centric trial in participants with and without orthodontic treatment and establish a regression equation for each region. Settings and Design: A cross-sectional multi-national, multi-centric correlation trial. Materials and Methods: A cross-sectional study was conducted in India and Malaysia with a total of 688 participants. Measurements of thumb and VDR were obtained using a modified Willi's gauge using a standard operating procedure. Statistical Analysis Used: Pearson's correlation coefficient was calculated to determine the correlation between TL and VDR. A multiple linear regression was done to correlate VDR from gender, orthodontic treatment, and length of thumb. Results: Correlation coefficient between TL and VDR in patients with orthodontic treatment was 0.829 and 0.774 in patients without orthodontic treatment. The correlation between TL and VDR in patients with orthodontic treatment in North India was 0.484, P = 0.010 and Malaysia was 0.946, P < 0.001. There were significant correlations between TL and VDR in patients without orthodontic treatment in all regions (P < 0.001). Regression equations were obtained for different ethnic groups for calculating the VDR. Conclusion: There was an overall positive correlation between TL and VDR in patients with and without orthodontic treatment. The regression equations presented in this article could help clinicians in their clinical practice and researchers to conduct future trials.

Context Asian elephant numbers are declining across much of their range driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior. Objectives Our objectives were to (1) estimate the sizes of dry, wet, and annual ranges of wild elephants in Myanmar; and quantify the relationship between dry season (the period when human-elephant interactions are the most likely to occur) range size and configurations of agriculture and natural vegetation within the range, and (2) evaluate how percentage of agriculture within dry core range (50% AKDE range) of elephants relates to their daily distance traveled. Methods We used autocorrelated kernel density estimator (AKDE) based on a continuous-time movement modeling (ctmm) framework to estimate dry season (26 ranges from 22 different individuals), wet season (12 ranges from 10 different individuals), and annual range sizes (8 individuals), and reported the 95%, 50% AKDE, and 95% Minimum Convex Polygon (MCP) range sizes. We assessed how landscape characteristics influenced range size based on a broad array of 48 landscape metrics characterizing aspects of vegetation, water, and human features and their juxtaposition in the study areas. To identify the most relevant landscape metrics and simplify our candidate set of informative metrics, we relied on exploratory factor analysis and Spearman’s rank correlation coefficient. Based on this analysis we adopted a final set of metrics into our regression analysis. In a multiple regression framework, we developed candidate models to explain the variation in AKDE dry season range sizes based on the previously identified, salient metrics of landscape composition. Results Elephant dry season ranges were highly variable averaging 792.0 km 2 and 184.2 km 2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant’s range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area. Conclusion Our results provide baseline information on elephant spatial requirements and the factors affecting them in Myanmar. This information is important for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may further endanger already declining elephant populations in Myanmar and across the species’ range.

Hospital-based surveillance was conducted at two widely separated regions in Myanmar during the 2015 dengue epidemic. Acute phase serum samples were collected from 332 clinically diagnosed dengue patients during the peak season of dengue cases. Viremia levels were measured by quantitative real-time PCR and plaque assays using Fc𝛾RIIA-expressing and non-Fc𝛾RIIA-expressing BHK cells to specifically determine the infectious virus particles. By serology and molecular techniques, 280/332 (84·3%) were confirmed as dengue patients. All four serotypes of dengue virus (DENV) were isolated from among 104 laboratory-confirmed patients including two cases infected with two DENV serotypes. High percentage of primary infection was noted among the severe dengue patients. Patients with primary infection or DENV IgM negative demonstrated significantly higher viral loads but there was no significant difference among the severity groups. Viremia levels among dengue patients were notably high for a long period which was assumed to support the spread of the virus by the mosquito vector during epidemic. Phylogenetic analyses of the envelope gene of the epidemic strains revealed close similarity with the strains previously isolated in Myanmar and neighboring countries. DENV-1 dominated the epidemic in 2015 and the serotype (except DENV-3) and genotype distributions were similar in both study sites.

The strong present-day Asian monsoons are thought to have originated between 25 and 22 million years (Myr) ago, driven by Tibetan–Himalayan uplift. However, the existence of older Asian monsoons and their response to enhanced greenhouse conditions such as those in the Eocene period (55–34 Myr ago) are unknown because of the paucity of well-dated records. Here we show late Eocene climate records revealing marked monsoon-like patterns in rainfall and wind south and north of the Tibetan–Himalayan orogen. This is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from Myanmar, and by aeolian dust deposition in northwest China. Our climate simulations support modern-like Eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhanced greenhouse conditions counterbalanced the negative effect of lower Tibetan relief on precipitation. These strong monsoons later weakened with the global shift to icehouse conditions 34 Myr ago. Asian monsoons were strongly active 40 million years ago and were enhanced by high atmospheric CO 2 content. They were significantly weakened when CO 2 levels decreased 34 million years ago and then reinitiated several million years later. Monsoon conditions in a greenhouse world Asian monsoons were strongly active 40 million years ago and were enhanced by high atmospheric CO 2 content; however, they were significantly weakened when CO 2 levels decreased 34 million years ago and then reinitiated several million years later.

IntroductionPatients with either surgery-related or patient-related risk factors are at an increased risk of acute and chronic postsurgical pain (CPSP) and long-term opioid use. To improve recovery, prevent CPSP and decrease opioid use, we need to identify these patients before surgery and provide a multidisciplinary pain management strategy throughout hospital admission and follow-up in the postdischarge period. We hypothesise that a multidisciplinary transitional pain service (TPS) improves quality of recovery and reduce the incidence of CPSP and opioid consumption.Methods and analysisWe aim to investigate the effectiveness of implementation of a TPS for patients at risk of developing CPSP. The trial design is a pragmatic, open-label, randomised controlled trial (RCT). After stratification for sex, patients are randomly assigned to the TPS or standard of care (SOC) group. Our primary outcome is the quality of recovery, measured at the morning of the third postoperative day, employing the quality of recovery (QoR)-15 questionnaire. Secondary outcomes are the incidence of CPSP, opioid consumption and patient-reported outcome measures at 3 and 6 months postoperatively. We need to enrol 176 patients to detect a minimal clinical important difference of 8 points on the QoR-15 score.Ethics and disseminationEthics approval was obtained by the accredited medical research ethics committee of the Academic Medical Center in Amsterdam (2020_211) on 15 October 2020. Protocol version 3.2 was approved on 25 January 2020. The trial is registered with the Netherlands Trial Register, NL9115. The results will be disseminated by open access publication in a peer-reviewed journal.Trial registration number NL9115

Background Syphilis is a sexually and vertically transmitted infection caused by the bacteria Treponema pallidum for which there are few proven alternatives to penicillin for treatment. For pregnant women infected with syphilis, penicillin is the only WHO-recommended treatment that will treat the mother and cross the placenta to treat the unborn infant and prevent congenital syphilis. Recent shortages, national level stockouts as well as other barriers to penicillin use call for the urgent identification of alternative therapies to treat pregnant women infected with syphilis. Methods This prospective, randomized, non-comparative trial will enroll non-pregnant women aged 18 years and older with active syphilis, defined as a positive rapid treponemal and a positive non-treponemal RPR test with titer ≥1:16. Women will be randomized in a 2:1 ratio to receive the oral third generation cephalosporin cefixime at a dose of 400 mg two times per day for 10 days ( n  = 140) or benzathine penicillin G 2.4 million units intramuscularly based on the stage of syphilis infection ( n  = 70). RPR titers will be collected at enrolment, and at three, six, and nine months following treatment. Participants experiencing a 4-fold (2 titer) decline by six months will be considered as having an adequate or curative treatment response. Discussion Demonstration of efficacy of cefixime in the treatment of active syphilis in this Phase 2 trial among non-pregnant women will inform a proposed randomized controlled trial to evaluate cefixime as an alternative treatment for pregnant women with active syphilis to evaluate prevention of congenital syphilis. Trial registration Trial identifier: www.Clinicaltrials.gov, NCT03752112 . Registration Date: November 22, 2018.