Metering gun for dispensing precisely measured charges of fluid

A cyclically operable fluid dispenser for use in dispensing precisely measured charges of potable water aboard spacecraft is described. The dispenser is characterized by (1) a sealed housing adapted to be held within a crewman's palm and coupled with a pressurized source of potable water; (2) a dispensing jet projected from the housing and configured to be received within a crewman's lips; (3) an expansible measuring chamber for measuring charges of drinking water received from the source; (4) and a dispenser actuator including a lever extended from the housing to be digitated for initiating operational cycles, whereby precisely measured charges of potable water selectively are delivered for drinking purposes in a weightless environment

Does being unaware predict being unskilled? Analyzing the predictive ability of the Metacognition Awareness Inventory

Students’ perceptions of how well they know information ultimately impact the study choices they make. The more accurate these perceptions are, the more prepared students are to be academically successful. Thus, the current study aimed to find an efficient way to quickly identify students who struggle with this self-assessment, and ultimately classroom performance, using a tool designed to assess metacognitive ability. Participants first completed a metacognition scale designed to assess learning strategies – the Metacognitive Awareness Inventory (MAI). Next, the participants were administered a 29-minute lecture followed by a brief exam at the end of the lecture. There were three types of metacognitive judgements used in this study: a) A global predictive judgment, b) item-by-item confidence judgments, and c) a global postdictive judgment. The exam results were compared to participants’ self-report on the MAI and participants’ judgements. It was hypothesized that participants with higher MAI scores would do consistently better on the post-lecture exam than participants with lower MAI scores and be more accurate with their metacognitive judgments. Additionally, it was hypothesized that participants in the lowest metacognitive quadrant on the MAI would be overconfident in their predictions of exam performance. Neither hypothesis was supported: The MAI does not appear to be a reliable measure for predicting accuracy of metacognitive judgments or immediate academic performance

Recently fixed carbon fuels microbial activity several meters below the soil surface

This data file (Scheibe_2022.xlsx) contains radiocarbon data of bulk soil carbon and CO2 respired in incubations from soil profiles in three climate zones (arid, mediterranean, and humid) of the Costal Cordillera of Chile down to a depth of six meters. Variable descriptions are provided in Template Info File. The data are part of a study, which investigates how soil microbial carbon cycling affects soil formation especially in the critical zone by understanding the carbon source of microbial activity in deep soil. The study was conducted within the framework of the Deep EarthShape priority program funded by the German Science Foundation (DFG-SPP 1803)

HIV prevention among female sex workers in Africa

Sex work occurs to meet the demand for sexual services and is a universal phenomenon. In Africa sex work takes many forms and is an important source of income for many women. Yet sex worker reproductive health needs remain largely unmet. The criminalisation of sex work; community and service provider stigma; violence; substance use and limited access to health services and prevention commodities contribute to the high HIV burden evident among female sex workers in Africa. Following UNAIDS’ three pillar approach to HIV prevention and sex work we present an overview of current opportunities, barriers and suggestions to improve HIV prevention policy and programming for sex work in Africa. Universal access to a comprehensive package of HIV services is the first pillar. Reproductive health commodities; voluntary and anonymous HIV counselling andtesting; treatment of sexually transmitted infections, HIV and opportunistic infections; harm reduction for substance use and psychosocial support services make up the recommended package of services. The second pillar is a sex worker-supportive environment. The inclusion of sex worker programmes within national HIV strategic planning; sex worker-led community mobilisation and the establishment of sex work community networks (comprised of sex workers, health service providers, law enforcers and other stakeholders) enable effective programme implementation and are recommended. The reduction of sex worker vulnerability and addressing structural issues form the final pillar. The decriminalisation of sex work; development of supportive policy; gender equality and economic development are key factors that need to be addressed to increase sex worker resilience. Evidence supports the public health benefit of human rights based approaches to HIV prevention; moralistic and restrictive policy and laws towards sex work are harmful and should be removed. The establishment of these pillars will increase sex worker safety and enhance the inclusiveness of the HIV response

Non-Markovian quantum state diffusion for absorption spectra of molecular aggregates

In many molecular systems one encounters the situation where electronic excitations couple to a quasi-continuum of phonon modes. That continuum may be highly structured e.g. due to some weakly damped high frequency modes. To handle such a situation, an approach combining the non-Markovian quantum state diffusion (NMQSD) description of open quantum systems with an efficient but abstract approximation was recently applied to calculate energy transfer and absorption spectra of molecular aggregates [Roden, Eisfeld, Wolff, Strunz, PRL 103 (2009) 058301]. To explore the validity of the used approximation for such complicated systems, in the present work we compare the calculated (approximative) absorption spectra with exact results. These are obtained from the method of pseudomodes, which we show to be capable of determining the exact spectra for small aggregates and a few pseudomodes. It turns out that in the cases considered, the results of the two approaches mostly agree quite well. The advantages and disadvantages of the two approaches are discussed

Inter-species variation in the oligomeric states of the higher plant Calvin cycle enzymes glyceraldehyde-3-phosphate dehydrogenase and phosphoribulokinase

In darkened leaves the Calvin cycle enzymes glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK) form a regulatory multi-enzyme complex with the small chloroplast protein CP12. GAPDH also forms a high molecular weight regulatory mono-enzyme complex. Given that there are different reports as to the number and subunit composition of these complexes and that enzyme regulatory mechanisms are known to vary between species, it was reasoned that protein-protein interactions may also vary between species. Here, this variation is investigated. This study shows that two different tetramers of GAPDH (an A2B2 heterotetramer and an A4 homotetramer) have the capacity to form part of the PRK/GAPDH/CP12 complex. The role of the PRK/GAPDH/CP12 complex is not simply to regulate the 'non-regulatory' A4 GAPDH tetramer. This study also demonstrates that the abundance and nature of PRK/GAPDH/CP12 interactions are not equal in all species and that whilst NAD enhances complex formation in some species, this is not sufficient for complex formation in others. Furthermore, it is shown that the GAPDH mono-enzyme complex is more abundant as a 2(A2B2) complex, rather than the larger 4(A2B2) complex. This smaller complex is sensitive to cellular metabolites indicating that it is an important regulatory isoform of GAPDH. This comparative study has highlighted considerable heterogeneity in PRK and GAPDH protein interactions between closely related species and the possible underlying physiological basis for this is discussed. © 2011 The Author(s)

A SWOT analysis of health service access by men who have sex with men in South Africa: lessons for higher education institutions

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Multiscale modelling and simulation, 13th international workshop

Multiscale Modelling and Simulation (MMS) is a cornerstone in the today's research in computational science. Simulations containing multiple models, with each model operating at a different temporal or spatial scale, are a challenging setting that frequently require innovative approaches in areas such as scale bridging, code deployment, error quantification, and scientific analysis. The aim of the MMS workshop is to encourage and consolidate the progress in this multidisciplinary research field, both in the areas of the scientific applications and the underlying infrastructures that enable these applications. Here we briefly introduce the scope of the workshop and highlight some of the key aspects of this year's submissions