Cohesin cleavage by separase is enhanced by a substrate motif distinct from the cleavage site.

Chromosome segregation begins when the cysteine protease, separase, cleaves the Scc1 subunit of cohesin at the metaphase-to-anaphase transition. Separase is inhibited prior to metaphase by the tightly bound securin protein, which contains a pseudosubstrate motif that blocks the separase active site. To investigate separase substrate specificity and regulation, here we develop a system for producing recombinant, securin-free human separase. Using this enzyme, we identify an LPE motif on the Scc1 substrate that is distinct from the cleavage site and is required for rapid and specific substrate cleavage. Securin also contains a conserved LPE motif, and we provide evidence that this sequence blocks separase engagement of the Scc1 LPE motif. Our results suggest that rapid cohesin cleavage by separase requires a substrate docking interaction outside the active site. This interaction is blocked by securin, providing a second mechanism by which securin inhibits cohesin cleavage

Testing the Extremes of Initial Mass Function Variability using Compact Stellar Systems

The initial mass function (IMF) is a cornerstone in star formation and galaxy evolution studies. It has traditionally been assumed to be universal, but this has been challenged by increasingly detailed observations of diverse, extragalactic stellar populations. However, this observed variability in the IMF is debated as a sufficient theoretical framework to explain it has not yet been substantiated. A major limitation is that these observations have only probed narrow regions of mass-metallicity-density parameter space (i.e. metal-rich, early-type galaxies). We present an unprecedented sample of integrated light spectroscopy of diverse objects, including "compact" stellar systems (CSSs, i.e. globular clusters and ultra-compact dwarf galaxies) and brightest cluster galaxies. Our sample covers a wide range of metallicities (-1.7 < [Fe/H] < 0.01) and velocity dispersions (7.4 km/s < σ < 275 km/s). We carefully reduce high S/N Keck LRIS spectra and measure the IMF by employing a new suite of full-spectrum stellar population synthesis models. These simultaneously fit for ages, metallicities, and detailed chemical abundances, allowing us to robustly measure the effects of the IMF. We show that CSSs do not follow trends with physical parameters that have been found for early-type galaxies (ETGs). In particular, previously established metallicity-dependent trends with the IMF may change in complex ways. We examine potential factors that could be causing the population of CSSs to contrast with the ETGs in this parameter space

Effect of long-term cannabidiol on learning and anxiety in a female Alzheimer’s disease mouse model

Cannabidiol is a promising potential therapeutic for neurodegenerative diseases, including Alzheimer’s disease (AD). Our laboratory has shown that oral CBD treatment prevents cognitive impairment in a male genetic mouse model of AD, the amyloid precursor protein 1 x presenilin 1 hemizygous (APPxPS1) mouse. However, as sex differences are evident in clinical populations and in AD mouse models, we tested the preventive potential of CBD therapy in female APPxPS1 mice. In this study, 2.5-month-old female wildtype-like (WT) and APPxPS1 mice were fed 20 mg/kg CBD or a vehicle via gel pellets daily for 8 months and tested at 10.5 months in behavioural paradigms relevant to cognition (fear conditioning, FC; cheeseboard, CB; and novel object recognition test, NORT) and anxiety-like behaviours (elevated plus maze, EPM). In the CB, CBD reduced latencies to find a food reward in APPxPS1 mice, compared to vehicle-treated APPxPS1 controls, and this treatment effect was not evident in WT mice. In addition, CBD also increased speed early in the acquisition of the CB task in APPxPS1 mice. In the EPM, CBD increased locomotion in APPxPS1 mice but not in WT mice, with no effects of CBD on anxiety-like behaviour. CBD had limited effects on the expression of fear memory. These results indicate preventive CBD treatment can have a moderate spatial learning-enhancing effect in a female amyloid-β-based AD mouse model. This suggests CBD may have some preventive therapeutic potential in female familial AD patients

Psychological traits and public attitudes towards abortion: the role of empathy, locus of control, and need for cognition

In the summer of 2022, the U.S. Supreme Court overturned the historic Roe v. Wade ruling, prompting various states to put forth ballot measures regarding state-level abortion rights. While earlier studies have established associations between demographics, such as religious beliefs and political ideologies, and attitudes toward abortion, the current research delves into the role of psychological traits such as empathy, locus of control, and need for cognition. A sample of 294 U.S. adults was obtained via Amazon Mechanical Turk, and participants were asked to provide their attitudes on seven abortion scenarios. They also responded to scales measuring empathy toward the pregnant woman and the unborn, locus of control, and need for cognition. Principal Component Analysis divided abortion attitudes into two categories: traumatic abortions (e.g., pregnancies due to rape) and elective abortions (e.g., the woman does not want the child anymore). After controlling for religious belief and political ideology, the study found psychological factors accounted for substantial variation in abortion attitudes. Notably, empathy toward the pregnant woman correlated positively with abortion support across both categories, while empathy toward the unborn revealed an inverse relationship. An internal locus of control was positively linked to support for both types of abortions. Conversely, external locus of control and need for cognition only positively correlated with attitudes toward elective abortion, showing no association with traumatic abortion attitudes. Collectively, these findings underscore the significant and unique role psychological factors play in shaping public attitudes toward abortion. Implications for research and practice were discussed

Improving Strength Properties of Paper Utilizing Mycelia Fungus

Alternatives to the traditional sack grade of paper used for grocery bags was investigated for use in the commercial market. This project investigated the use of mycelium in conjunction with wood-based pulps to produce a structurally enhanced paper sheet. The study included creating and testing a fibrous sheet containing a network of mycelium. Three mycelium types were used: Reishi (Ganoderma Lucidum), Pearl (Pleurotus Ostreatus var. Columbus), and Enoki (Flammulina Velutipes). All three require similar growth conditions but have different growth patterns. Three major trials were run, providing the mycelium with different growth conditions and medium. The first was a simple inoculation. The second was an inoculation of filter paper that was then stored in petri dishes to help reduce the mold growth discovered in the first trial. And the third was an inoculation of pulp slurries that were left to grow before being converted into small sheets. The slurry samples were made with both bleached and unbleached pulp to see if the type of pulp affected the growth. The mechanical properties of the developed materials were evaluated and compared to control samples of each pulp medium. Testing of the mycelium sheets was minimal because of poor growth, mold buildup, and an insubstantial number of samples per trial. Visual inspection under a microscope with 2x magnification and low angle light revealed areas of shiny, hairlike tendrils, protruding off the surface. In some cases, the tendrils appeared to grow over dark mold spots. Under visual inspection only, Pearl had the most clear and substantial growth. After visual inspection, the sheets were tested mechanically in hopes of more sufficient data; the grammage and tensile strength were measured. Strength comparisons were separated based on the inoculation method--inoculated onto pre-formed sheets or added to pulp slurry. The collected data indicated that Reishi grown on bleached pulp was the strongest. In general, inoculated samples of pulp turned out stronger than the original or plain sheets for bleached pulp and weaker for unbleached pulp

FACET: Fairness in Computer Vision Evaluation Benchmark

Computer vision models have known performance disparities across attributes such as gender and skin tone. This means during tasks such as classification and detection, model performance differs for certain classes based on the demographics of the people in the image. These disparities have been shown to exist, but until now there has not been a unified approach to measure these differences for common use-cases of computer vision models. We present a new benchmark named FACET (FAirness in Computer Vision EvaluaTion), a large, publicly available evaluation set of 32k images for some of the most common vision tasks - image classification, object detection and segmentation. For every image in FACET, we hired expert reviewers to manually annotate person-related attributes such as perceived skin tone and hair type, manually draw bounding boxes and label fine-grained person-related classes such as disk jockey or guitarist. In addition, we use FACET to benchmark state-of-the-art vision models and present a deeper understanding of potential performance disparities and challenges across sensitive demographic attributes. With the exhaustive annotations collected, we probe models using single demographics attributes as well as multiple attributes using an intersectional approach (e.g. hair color and perceived skin tone). Our results show that classification, detection, segmentation, and visual grounding models exhibit performance disparities across demographic attributes and intersections of attributes. These harms suggest that not all people represented in datasets receive fair and equitable treatment in these vision tasks. We hope current and future results using our benchmark will contribute to fairer, more robust vision models. FACET is available publicly at https://facet.metademolab.com

Initial mass function variability from the integrated light of diverse stellar systems

We present a uniform analysis of the stellar initial mass function (IMF) from integrated light spectroscopy of 15 compact stellar systems (11 globular clusters in M31 and 4 ultra compact dwarfs in the Virgo cluster, UCDs) and two brightest Coma cluster galaxies (BCGs), covering a wide range of metallicities ($-$1.7 $<$ [Fe/H] $<$ 0.01) and velocity dispersions (7.4 km~s$^{-1}$ $< \sigma <$ 275 km~s$^{-1}$). The S/N $\sim 100$ \AA$^{-1}$ Keck LRIS spectra are fitted over the range 4000<\lambda/\mbox{\AA}<10,000 with flexible, full-spectrum stellar population synthesis models. We use the models to fit simultaneously for ages, metallicities, and individual elemental abundances of the population, allowing us to decouple abundance variations from variations in IMF slope. We show that compact stellar systems do not follow the same trends with physical parameters that have been found for early-type galaxies. Most globular clusters in our sample have an IMF consistent with that of the Milky Way, over a wide range of [Fe/H] and [Mg/Fe]. There is more diversity among the UCDs, with some showing evidence for a bottom-heavy IMF, but with no clear correlation with metallicity, abundance, or velocity dispersion. The two Coma BCGs have similar velocity dispersion and metallicity, but we find the IMF of NGC~4874 is consistent with that of the Milky Way while NGC~4889 presents evidence for a significantly bottom-heavy IMF. For this sample, the IMF appears to vary between objects in a way that is not explained by a single metallicity-dependent prescription.Comment: Accepted for publication in MNRA

Exploring the extent to which alcohol control interventions targeting affordability, availability and marketing are sex- and gender-responsive

INTRODUCTION: Sex and gender are important determinants of alcohol consumption and its impact on health. Therefore, there is a need to understand if and how alcohol control interventions work differently for people of different sexes and genders. OBJECTIVE: To assess the extent to which research on alcohol control interventions targeting affordability, availability and marketing is sex- and genderresponsive. INCLUSION CRITERIA: With no restriction on the population, study context, intervention outcome and publication year, review-type articles exploring alcohol control interventions targeting affordability, availability and marketing will be included. Only peer-reviewed papers published in the English language will be considered. Review articles with no intervention outcome, primary research articles and non-peer-reviewed publications will be excluded. METHODS: At the time of publication, the review is at the data extraction stage. A systematic search strategy using Ovid MEDLINE, Web of Science, Scopus and Web of Science was conducted. This was supplemented by forward and backward citation chasing and Google Scholar searches. All retrieved records were uploaded to Covidence, deduplicated and screened for relevance. Title and abstract screening was conducted using a dual screening approach. Full-text screening was undertaken by one researcher, with 40% of the records double-screened. Data extraction is being conducted pro forma using a piloted instrument adapted from the Sex and Gender Appraisal Tool-Systematic Reviews-2 tool. It is anticipated that 10% of the records will be independently checked by another researcher. Data analysis will take the form of narrative interpretation, supported by appropriate descriptive statistics and visualisation tools such as tables and graphs