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Layered transition metal dichalcogenide (TMD) materials have attracted great interest for applications in electronics. Here, we report a method to synthesize TMD materials at controlled locations with the desired layer number. Metal oxide precursors are patterned on the growth substrate by photolithography, and then a mixture of sodium chloride and sodium cholate growth promoters is applied to enable the growth of monolayer and bilayer TMDs with large flake sizes. The quality of the bilayer flakes is examined by atomic force microscopy, Auger electron spectroscopy, Raman spectroscopy, photoluminescence spectroscopy, and transmission electron microscopy. Electrical performance is evaluated by fabricating three-terminal field-effect transistors that demonstrate high carrier mobilities and on/off ratios larger than 105. This approach provides insights into future device applications and integration strategies based on layered TMD materials.

Disaster research is essential for developing more robust and contextualised policies. It is, therefore, no surprise that multilateral organisations like the United Nations and the World Bank have called for enhanced disaster-related frameworks, legislation and policies in developing countries using quality data. However, internal and external researchers and practitioners often face significant challenges collecting data in these nations because of a range of problems including, but not limited to, incomplete sampling frames, inadequate infrastructure or unstable governments. This reality leads one to question: is the cart coming before the horse? This study explored individual and household (IH) preparedness in The Bahamas – a small island developing state in the Caribbean. An online survey was used, and 629 Bahamians opted to participate. However, the researchers faced many barriers to collecting representative data. This case study, therefore, discusses the range of methodological challenges faced by the researchers and their impact on this study. Contribution: This article substantially contributes to the disaster literature by exploring the challenges associated with conducting IH preparedness research in The Bahamas. This article also reminds practitioners and academics of the issues associated with collecting data in developing nations and its implications for policy enhancement and development. Furthermore, the authors present various recommendations ranging from enhanced funding to recognising the need for methodological innovation to support continuous research in countries like The Bahamas.

Electromagnetic ion cyclotron (EMIC) waves play important roles in particle loss processes in the magnetosphere. Determining the evolution of EMIC waves as they propagate and how this evolution affects wave-particle interactions requires accurate knowledge of the wave vector, k. We present a technique using the curl of the wave magnetic field to determine k observationally, enabled by the unique configuration and instrumentation of the Magnetospheric MultiScale (MMS) spacecraft. The wave curl analysis is demonstrated for synthetic arbitrary electromagnetic waves with varying properties typical of observed EMIC waves. The method is also applied to an EMIC wave interval observed by MMS on October 28, 2015. The derived wave properties and k from the wave curl analysis for the observed EMIC wave are compared with the Waves in Homogenous, Anisotropic, Multi-component Plasma (WHAMP) wave dispersion solution and with results from other single- and multi-spacecraft techniques. We find good agreement between k from the wave curl analysis, k determined from other observational techniques, and k determined from WHAMP. Additionally, the variation of k due to the time and frequency intervals used in the wave curl analysis is explored. This exploration demonstrates that the method is robust when applied to a wave containing at least 3-4 wave periods and over a rather wide frequency range encompassing the peak wave emission. These results provide confidence that we are able to directly determine the wave vector properties using this multi-spacecraft method implementation, enabling systematic studies of EMIC wave k properties with MMS.

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 30 vinylpyrrolidone polymers as used in cosmetic products; most of these ingredients have the reported cosmetic function of film former in common. The Panel reviewed data relevant to the safety of these ingredients, and determined that 27 vinylpyrrolidone polymers are safe in cosmetics in the present practices of use and concentration described in the safety assessment. The Panel also concluded that the available data are insufficient to make a determination that 3 vinylpyrrolidone polymers (all urethanes) are safe under the intended conditions of use in cosmetic formulations. [ABSTRACT FROM AUTHOR]

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 10 polyol phosphates. Some of the possible functions in cosmetics that are reported for this ingredient group are chelating agents, oral care agents, and skin conditioning agents. The Panel reviewed relevant data relating to the safety of these ingredients under the intended conditions of use in cosmetic formulations, and concluded that Sodium Phytate, Phytic Acid, Phytin, and Trisodium Inositol Triphosphate are safe in cosmetics in the present practices of use and concentration described in the safety assessment. The Panel also concluded that the data are insufficient to determine the safety of the following 6 ingredients as used in cosmetics: Disodium Glucose Phosphate, Manganese Fructose Diphosphate, Sodium Mannose Phosphate, Trisodium Fructose Diphosphate, Xylityl Phosphate, and Zinc Fructose Diphosphate. [ABSTRACT FROM AUTHOR]

The Expert Panel for Cosmetic Ingredient Safety (Panel) reviewed the safety of 10 alkanoyl lactyl lactate salts. These ingredients have the surfactant function in cosmetics in common. The Panel reviewed data relevant to the safety of these ingredients, and concluded that these 10 ingredients are safe in cosmetics in the present practices of use and concentration described in the safety assessment when formulated to be nonirritating and nonsensitizing, which may be based on a quantitative risk assessment (QRA) or other accepted methodologies. [ABSTRACT FROM AUTHOR]

Purpose: There is little consensus in the literature regarding a) what it means for a school leader to lead with data, and b) how to measure data-informed leadership in a reliable and valid way. This study examines the psychometric properties of an operational measure intended to assess the extent to which a school leader is a 'data-informed school leader. The measurement invariance, reliabilities and construct and predictive validities of the Data-Informed School Leadership Survey (DISL Survey) are assessed using various psychometric statistical techniques. Methods: Using data collected from 155 teachers from 7 public schools in a southern state, the following psychometric statistics used to address our purpose: the Many-Facet Rasch (MFR) Model, Bayesian second-order Confirmatory Factor Analysis (CFA), Bayesian Structural Equation Modeling- Multiple Indicators, Multiple Causes analysis (Bayesian SEM-MIMIC), and reliability analysis. Findings: Results show an adequate fit from all MFR, Bayesian CFA, and MIMIC models and a high reliability (Cronbach α =.98). The DISL Survey instrument exhibits sound psychometric properties. Results likewise confirm the value of using MFR modeling and Bayesian methods to examine the psychometric properties of DISL Survey as a means of improving educational leadership measures. Implications for Research and Practice: Data from this study confirm the validity and reliability of the Data-Informed School Leadership Survey (DISL Survey) as an instrument to assess the strengths and weaknesses of Data-Informed School Leadership (DISL) and as a means for providing feedback for improving such leadership. Heretofore a measure for assessing this leadership was non-existent. [ABSTRACT FROM AUTHOR]

Layered transition metal dichalcogenide (TMD) materials have attracted great interest for applications in electronics. Here, we report a method to synthesize TMD materials at controlled locations with the desired layer number. Metal oxide precursors are patterned on the growth substrate by photolithography, and then a mixture of sodium chloride and sodium cholate growth promoters is applied to enable the growth of monolayer and bilayer TMDs with large flake sizes. The quality of the bilayer flakes is examined by atomic force microscopy, Auger electron spectroscopy, Raman spectroscopy, photoluminescence spectroscopy, and transmission electron microscopy. Electrical performance is evaluated by fabricating three-terminal field-effect transistors that demonstrate high carrier mobilities and on/off ratios larger than 105. This approach provides insights into future device applications and integration strategies based on layered TMD materials. [ABSTRACT FROM AUTHOR]

The Younger Dryas boundary (YDB) cosmic-impact hypothesis is based on considerable evidence that Earth collided with fragments of a disintegrating ≥100-km-diameter comet, the remnants of which persist within the inner solar system ∼12,800 y later. Evidence suggests that the YDB cosmic impact triggered an “impact winter” and the subsequent Younger Dryas (YD) climate episode, biomass burning, late Pleistocene megafaunal extinctions, and human cultural shifts and population declines. The cosmic impact deposited anomalously high concentrations of platinum over much of the Northern Hemisphere, as recorded at 26 YDB sites at the YD onset, including the Greenland Ice Sheet Project 2 ice core, in which platinum deposition spans ∼21 y (∼12,836–12,815 cal BP). The YD onset also exhibits increased dust concentrations, synchronous with the onset of a remarkably high peak in ammonium, a biomass-burning aerosol. In four ice-core sequences from Greenland, Antarctica, and Russia, similar anomalous peaks in other combustion aerosols occur, including nitrate, oxalate, acetate, and formate, reflecting one of the largest biomass-burning episodes in more than 120,000 y. In support of widespread wildfires, the perturbations in CO2 records from Taylor Glacier, Antarctica, suggest that biomass burning at the YD onset may have consumed ∼10 million km2, or ∼9% of Earth’s terrestrial biomass. The ice record is consistent with YDB impact theory that extensive impact-related biomass burning triggered the abrupt onset of an impact winter, which led, through climatic feedbacks, to the anomalous YD climate episode.

Part 1 of this study investigated evidence of biomass burning in global ice records, and here we continue to test the hypothesis that an impact event at the Younger Dryas boundary (YDB) caused an anomalously intense episode of biomass burning at ∼12.8 ka on a multicontinental scale (North and South America, Europe, and Asia). Quantitative analyses of charcoal and soot records from 152 lakes, marine cores, and terrestrial sequences reveal a major peak in biomass burning at the Younger Dryas (YD) onset that appears to be the highest during the latest Quaternary. For the Cretaceous-Tertiary boundary (K-Pg) impact event, concentrations of soot were previously utilized to estimate the global amount of biomass burned, and similar measurements suggest that wildfires at the YD onset rapidly consumed ∼10 million km2 of Earth’s surface, or ∼9% of Earth’s biomass, considerably more than for the K-Pg impact. Bayesian analyses and age regressions demonstrate that ages for YDB peaks in charcoal and soot across four continents are synchronous with the ages of an abundance peak in platinum in the Greenland Ice Sheet Project 2 (GISP2) ice core and of the YDB impact event (12,835–12,735 cal BP). Thus, existing evidence indicates that the YDB impact event caused an anomalously large episode of biomass burning, resulting in extensive atmospheric soot/dust loading that triggered an “impact winter.” This, in turn, triggered abrupt YD cooling and other climate changes, reinforced by climatic feedback mechanisms, including Arctic sea ice expansion, rerouting of North American continental runoff, and subsequent ocean circulation changes.

What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extrasolar planets yet to be discovered.

© 2015 Johnson et al.The African clawed frog Xenopus laevis is an important model organism for studies in developmental and cell biology, including cell-signaling. However, our knowledge of X. laevis protein post-translational modifications remains scarce.

Mapping host-pathogen interactions has proven instrumental for understanding how viruses manipulate host machinery and how numerous cellular processes are regulated. DNA viruses such as herpesviruses have relatively large coding capacity and thus can target an extensive network of cellular proteins. To identify the host proteins hijacked by this pathogen, we systematically affinity tagged and purified all 89 proteins of Kaposi's sarcoma-associated herpesvirus (KSHV) from human cells. Mass spectrometry of this material identified over 500 virus-host interactions. KSHV causes AIDS-associated cancers, and its interaction network is enriched for proteins linked to cancer and overlaps with proteins that are also targeted by HIV-1. We found that the conserved KSHV protein ORF24 binds to RNA polymerase II and brings it to viral late promoters by mimicking and replacing cellular TATA-box-binding protein (TBP). This is required for herpesviral late gene expression, a complex and poorly understood phase of the viral lifecycle.

The article explains how the enforcement of racially restrictive covenant is state action in the case Shelley V. Kraemer. Topics discussed include contractual issues raised by restrictive covenants, servitudes and use of property law to explain racially restrictive covenants, Recordings Acts as the key to enforceable equitable servitudes and state action, impact of Recording Act on contractual rights, actions created by the state to benefit the state, and other discriminatory land transfers.

Objectives. To describe all-outcome injurious shootings by police and compare characteristics of fatal versus nonfatal injurious shootings nationally. Methods. From July 2021 to April 2023, we manually reviewed publicly available records on all 2015–2020 injurious shootings by US police, identified from Gun Violence Archive. We estimated injury frequency, case fatality rates, and relative odds of death by incident and victim characteristics. Results. A total of 1769 people were injured annually in shootings by police, 55% fatally. When a shooting injury occurred, odds of fatality were 46% higher following dispatched responses than police-initiated responses. Injuries associated with physically threatening or threat-making behaviors, behavioral health needs, and well-being checks were most frequently fatal. Relative to White victims, Black victims were overrepresented but had 35% lower odds of fatal injury when shot. Conclusions. This first multiyear, nationwide analysis of injurious shootings by US police suggests that injury disparities are underestimated by fatal shootings alone. Nonpolicing responses to social needs may prevent future injuries. Public Health Implications. We call for enhanced reporting systems, comprehensive evaluation of emerging reforms, and targeted investment in social services for equitable injury prevention. (Am J Public Health. 2024;114(4):387–397. https://doi.org/10.2105/AJPH.2023.307560) [ABSTRACT FROM AUTHOR]

Summary: Selective block of NaV1.7 promises to produce non-narcotic analgesic activity without motor or cognitive impairment. Several NaV1.7-selective blockers have been reported, but efficacy in animal pain models required high multiples of the IC50 for channel block. Here, we report a target engagement assay using transgenic mice that has enabled the development of a second generation of selective Nav1.7 inhibitors that show robust analgesic activity in inflammatory and neuropathic pain models at low multiples of the IC50. Like earlier arylsulfonamides, these newer acylsulfonamides target a binding site on the surface of voltage sensor domain 4 to achieve high selectivity among sodium channel isoforms and steeply state-dependent block. The improved efficacy correlates with very slow dissociation from the target channel. Chronic dosing increases compound potency about 10-fold, possibly due to reversal of sensitization arising during chronic injury, and provides efficacy that persists long after the compound has cleared from plasma. : Bankar et al. show that acylsulfonamides produce analgesic activity at low multiples of the IC50 for inhibition of NaV1.7, in contrast to studies with arylsulfonamides that required >10 times the IC50. The improvement correlates with longer residency time on the target channels. Keywords: pain, sodium channel, inherited erythromelalgia, diabetic neuropathy, residence time