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Simulations and experiments have revealed enormous transport rates through carbon nanotube (CNT) channels when a pressure gradient drives fluid flow, but comparatively little attention has been given to concentration-driven transport despite its importance in many fields. Here, membranes are fabricated with a known number of single-walled CNTs as fluid transport pathways to precisely quantify the diffusive flow through CNTs. Contrary to early experimental studies that assumed bulk or hindered diffusion, measurements in this work indicate that the permeability of small ions through single-walled CNT channels is more than an order of magnitude higher than through the bulk. This flow enhancement scales with the ion free energy of transfer from bulk solutions to a nanoconfined, lower-dielectric environment. Reported results suggest that CNT membranes can unlock dialysis processes with unprecedented efficiency.High-temperature pyrolysis of nitrogen (N)-rich, crystalline porous organic architectures in the presence of a metal precursor is an important chemical process in heterogeneous catalysis for the fabrication of highly porous N-carbon-supported metal catalysts. Herein, covalent triazine framework (CTF) and CTF-I (that is, CTF after charge modulation with iodomethane) are presented as sacrificial templates, for the synthesis of carbon-supported Ru catalysts-Ru-CTF-900 and Ru-CTF-I-900 respectively, following high-temperature pyrolysis at 900 °C under N2 atmosphere. Predictably, the dispersed Ru on pristine CTF carrier suffered severe sintering of the Ru nanoparticles (NPs) during heat treatment at 900 °C. However, the Ru-CTF-I-900 catalyst is composed of ultra-small Ru NPs and abundant Ru single atoms which may have resulted from much stronger Ru-N interactions. Through modification of the micro-environment within the CTF architecture, Ru precursor interacted on charged-modulated CTF framework shows electrostatic repulsion and steric hindrance, thus contributing toward the high density of single Ru atoms and even smaller Ru NPs after pyrolysis. A Ru-Ru coordination number of only 1.3 is observed in the novel Ru-CTF-I-900 catalyst, which exhibits significantly higher catalytic activity than Ru-CTF-900 for transfer hydrogenation of acetophenone.Influenza is one of the most widespread viral infections worldwide and represents a major public health problem. The risk that one of the next pandemics is caused by an influenza strain is high. It is important to develop broad-spectrum influenza antivirals to be ready for any possible vaccine shortcomings. Anti-influenza drugs are available but they are far from ideal. Arguably, an ideal antiviral should target conserved viral domains and be virucidal, that is, irreversibly inhibit viral infectivity. Here, a new class of broad-spectrum anti-influenza macromolecules is described that meets these criteria and display exceedingly low toxicity. These compounds are based on a cyclodextrin core modified on its primary face with long hydrophobic linkers terminated either in 6'sialyl-N-acetyllactosamine (6'SLN) or in 3'SLN. (R,S)-3,5-DHPG SLN enables nanomolar inhibition of the viruses while the hydrophobic linkers confer irreversibility to the inhibition. The combination of these two properties allows for efficacy in vitro against several human or avian influenza strains, as well as against a 2009 pandemic influenza strain ex vivo. Importantly, it is shown that, in mice, one of the compounds provides therapeutic efficacy when administered 24 h post-infection allowing 90% survival as opposed to no survival for the placebo and oseltamivir.Taking lessons from nature offers an increasing promise toward improved performance in man-made materials. Here new cement materials with unidirectionally porous architectures are developed by replicating the designs of natural wood using a simplified ice-templating technique in light of the retention of ice-templated architectures by utilizing the self-hardening nature of cement. link2 The wood-like cement exhibits higher strengths at equal densities than other porous cement-based materials along with unique multifunctional properties, including effective thermal insulation at the transverse profile, controllable water permeability along the vertical direction, and the easy adjustment to be water repulsive by hydrophobic treatment. The strengths are quantitatively interpreted by discerning the effects of differing types of pores using an equivalent element approach. The simultaneous achievement of high strength and multifunctionality makes the wood-like cement promising for applications as new building materials, and verifies the effectiveness of wood-mimetic designs in creating new high-performance materials. The simple fabrication procedure by omitting the freeze-drying treatment can also promote a better efficiency of ice-templating technique for the mass production in engineering and may be extended to other material systems.
Sleep disturbances, insomnia and recurrent nightmares in particular, are among the most frequently endorsed symptoms of posttraumatic stress disorder (PTSD). The present review provides a summary of the prevalence estimates and methodological challenges presented by sleep disturbances in PTSD, highlights the recent evidence for empirically supported psychotherapeutic and pharmacological interventions for comorbid sleep disturbances implicated in PTSD, and provides a summary of recent findings on integrated and sequential treatment approaches to ameliorate comorbid sleep disturbances in PTSD.
Insomnia, recurrent nightmares, and other sleep disorders are commonly endorsed among individuals with PTSD; however, several methodological challenges contribute to the varying prevalence estimates. Targeted sleep-focused therapeutic interventions can improve sleep symptoms and mitigate daytime PTSD symptoms. Recently, attention has focused on the role of integrated and sequential approaches, suggesting that comprehensively treating sleep disturbances in PTSD is likely to require novel treatment modalities.
Evidence is growing on the development, course, and treatment of comorbid sleep disturbances in PTSD. Further, interventions targeting sleep disturbances in PTSD show promise in reducing symptoms. However, longitudinal investigations and additional rigorous controlled trials with diverse populations are needed to identify key features associated with treatment response in order to alleviate symptoms.
Evidence is growing on the development, course, and treatment of comorbid sleep disturbances in PTSD. Further, interventions targeting sleep disturbances in PTSD show promise in reducing symptoms. However, longitudinal investigations and additional rigorous controlled trials with diverse populations are needed to identify key features associated with treatment response in order to alleviate symptoms.
The aim of this review is to present a comprehensive look at five intestinal soil-transmitted helminths (STHs) of global health importance that may continue to plague low-income and rural areas of the USA and argue the need for enhanced surveillance of these infections, which primarily affect the nation's most vulnerable groups.
Human STH infections in middle- and high-income countries are at particular risk for being undiagnosed; as common symptoms are non-specific, differentials require a high index of clinical suspicion, and cases are concentrated in areas of poverty where access to care is limited. Although autochthonous STHs are thought to be rare in the USA, infections were once common in the American South and Appalachia and robust epidemiologic surveillance is limited post 1980s. However, recent community studies and case reports from small-scale farms and areas of high rural or inner-city poverty reveal the potential for persisting helminth infections in distinct populations of the country.
STHs are among the most common neglected tropical diseases globally causing significant morbidity in underserved communities and contributing to the continuation of cycles of poverty within vulnerable populations. Due to possible severe disease sequalae and their ability to perpetuate poverty and poverty-associated health outcomes within already vulnerable groups, it is vital that surveillance for these infections is enhanced to bolster health equity in the USA.
STHs are among the most common neglected tropical diseases globally causing significant morbidity in underserved communities and contributing to the continuation of cycles of poverty within vulnerable populations. Due to possible severe disease sequalae and their ability to perpetuate poverty and poverty-associated health outcomes within already vulnerable groups, it is vital that surveillance for these infections is enhanced to bolster health equity in the USA.
This article outlines considerations for individuals interested in developing and implementing breast cancer risk models and has relevance for individuals developing risk-models with the goal of implementing them into health systems.
There has been increased focus on developing risk models for clinical use-often with less attention model implementation. Epidemiologists developing risk-models must think through model outcomes including stakeholder needs, time horizons, terminology and reference groups and clarity on what actionable steps are for health systems, providers and patients following its implementation.
Model performance needs to be evaluated relative to complexity of the model to be implemented-not just from the risk-prediction perspective, but also from the burden on patients, providers and systems for the amount and frequency of required data collection and with clear actionable steps to be taken with the information collected.
Model performance needs to be evaluated relative to complexity of the model to be implemented-not just from the risk-prediction perspective, but also from the burden on patients, providers and systems for the amount and frequency of required data collection and with clear actionable steps to be taken with the information collected.
Increasing access to large-scale genetic datasets in population-based studies allows for genetic association studies as a means to examine previously known and novel relationships among complex traits. In this review, we discuss two widely used approaches to leverage genetic data to study the links between traits Genome-wide genetic correlation and Mendelian Randomization (MR) studies.
Both genetic correlation and MR studies have provided important novel insights. However, although they are less sensitive to many sources of bias present in traditional, observational epidemiology, they still rely on assumptions that in practice might be difficult to assess. link3 To overcome this, development of novel methods less sensitive to these assumptions is an active area of research.
We believe that as population-based genetic datasets grow larger and novel methods allowing for weaker forms of current assumptions become available, genetic correlation and MR studies will become an integral part of genetic epidemiology studies.
We believe that as population-based genetic datasets grow larger and novel methods allowing for weaker forms of current assumptions become available, genetic correlation and MR studies will become an integral part of genetic epidemiology studies.