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Evolution of a ZW sex chromosome system in willows
No full textTransitions in the heterogamety of sex chromosomes (e.g., XY to ZW or vice versa) fundamentally alter the genetic basis of sex determination, however the details of these changes have been studied in only a few cases. In an XY to ZW transition, the X is likely to give rise to the W because they both carry feminizing genes and the X is expected to harbour less genetic load than the Y. Here, using a new reference genome for Salix exigua, we trace the X, Y, Z, and W sex determination regions during the homologous transition from an XY system to a ZW system in willow (Salix). We show that both the W and the Z arose from the Y chromosome. We find that the new Z chromosome shares multiple homologous putative masculinizing factors with the ancestral Y, whereas the new W lost these masculinizing factors and gained feminizing factors. The origination of both the W and Z from the Y was permitted by an unexpectedly low genetic load on the Y and this indicates that the origins of sex chromosomes during homologous transitions may be more flexible than previously considered
Multi-modal cross-linguistic perception of Mandarin tones in clear speech
No full textClearly enunciated speech (relative to conversational, plain speech) involves articulatory and acoustic modifications that enhance auditory–visual (AV) segmental intelligibility. However, little research has explored clear-speech effects on the perception of suprasegmental properties such as lexical tone, particularly involving visual (facial) perception. Since tone production does not primarily rely on vocal tract configurations, tones may be less visually distinctive. Questions thus arise as to whether clear speech can enhance visual tone intelligibility, and if so, whether any intelligibility gain can be attributable to tone-specific category-enhancing (code-based) clear-speech cues or tone-general saliency-enhancing (signal-based) cues. The present study addresses these questions by examining the identification of clear and plain Mandarin tones with visual-only, auditory-only, and AV input modalities by native (Mandarin) and nonnative (English) perceivers. Results show that code-based visual and acoustic clear tone modifications, although limited, affect both native and nonnative intelligibility, with category-enhancing cues increasing intelligibility and category-blurring cues decreasing intelligibility. In contrast, signal-based cues, which are extensively available, do not benefit native intelligibility, although they contribute to nonnative intelligibility gain. These findings demonstrate that linguistically relevant visual tonal cues are existent. In clear speech, such tone category-enhancing cues are incorporated with saliency-enhancing cues across AV modalities for intelligibility improvements
Aphid cluster recognition and detection in the wild using deep learning models
No full textAphid infestation poses a significant threat to crop production, rural communities, and global food security. While chemical pest control is crucial for maximizing yields, applying chemicals across entire fields is both environmentally unsustainable and costly. Hence, precise localization and management of aphids are essential for targeted pesticide application. The paper primarily focuses on using deep learning models for detecting aphid clusters. We propose a novel approach for estimating infection levels by detecting aphid clusters. To facilitate this research, we have captured a large-scale dataset from sorghum fields, manually selected 5447 images containing aphids, and annotated each individual aphid cluster within these images. To facilitate the use of machine learning models, we further process the images by cropping them into patches, resulting in a labeled dataset comprising 151,380 image patches. Then, we implemented and compared the performance of four state-of-the-art object detection models (VFNet, GFLV2, PAA, and ATSS) on the aphid dataset. Extensive experimental results show that all models yield stable similar performance in terms of average precision and recall. We then propose to merge close neighboring clusters and remove tiny clusters caused by cropping, and the performance is further boosted by around 17%. The study demonstrates the feasibility of automatically detecting and managing insects using machine learning models. The labeled dataset will be made openly available to the research community
Nanoalum Formulations Containing Aluminum Hydroxide and CpG 1018 Adjuvants: The Effect on Stability and Immunogenicity of a Recombinant SARS-CoV-2 RBD Antigen
No full textAluminum-salt vaccine adjuvants (alum) are commercially available as micron-sized particles with varying chemical composition and crystallinity. There are reports of enhanced adjuvanticity when the alum's particle size is reduced to the nanometer range. Previously, we demonstrated that a recombinant receptor-binding domain (RBD)-based COVID-19 vaccine candidate (RBD-J; RBD-L452K-F490W) formulated with aluminum hydroxide (Alhydrogel; AH) and CpG 1018™ (CpG) adjuvants induced potent neutralizing antibody responses in mice yet displayed instability during storage. In this work, we evaluated whether sonication of AH to the nanometer size range (nanoAH) could further enhance immunogenicity or improve storage stability of the above formulation. The addition of CpG to nanoAH (at mouse doses), however, caused re-agglomeration of nanoAH. AH-CpG interactions were evaluated by Langmuir binding isotherms and zeta potential measurements, and stabilized nanoAH + CpG formulations of RBD-J were then designed by (1) optimizing CpG:Aluminum dose ratios or (2) adding a small-molecule polyanion (phytic acid, PA). Compared with the micron-sized AH + CpG formulation, the two stabilized nanoAH + CpG formulations of RBD-J demonstrated no enhancement in SARS-CoV-2 pseudovirus neutralizing titers in mice, but the PA-containing nanoAH + CpG formulation showed improved RBD-J storage stability trends (at 4, 25, and 37 °C). The formulation protocols presented herein can be employed to evaluate the potential benefits of the nanoAH + CpG adjuvant combination with other vaccine antigens in different animal models
Climate change projected to impact structural hillslope connectivity at the global scale
No full textStructural connectivity describes how landscapes facilitate the transfer of matter and plays a critical role in the flux of water, solutes, and sediment across the Earth’s surface. The strength of a landscape’s connectivity is a function of climatic and tectonic processes, but the importance of these drivers is poorly understood, particularly in the context of climate change. Here, we provide global estimates of structural connectivity at the hillslope level and develop a model to describe connectivity accounting for tectonic and climate processes. We find that connectivity is primarily controlled by tectonics, with climate as a second order control. However, we show climate change is projected to alter global-scale connectivity at the end of the century (2070 to 2100) by up to 4% for increasing greenhouse gas emission scenarios. Notably, the Ganges River, the world’s most populated basin, is projected to experience a large increase in connectivity. Conversely, the Amazon River and the Pacific coast of Patagonia are projected to experience the largest decreases in connectivity. Modeling suggests that, as the climate warms, it could lead to increased erosion in source areas, while decreased rainfall may hinder sediment flow downstream, affecting landscape connectivity with implications for human and environmental health
Doctors for the people? The problematic distribution of rural service doctors in Ecuador
No full textPrimary health care is at the core of health systems that aim to ensure equitable health outcomes. With an estimated 36% of rural population, Ecuador has a service year programme (created in 1970) for recently graduated doctors to provide primary care services in rural and remote communities. However, little has been done to monitor or evaluate the programme since its inception. The aim of this study was to assess Ecuador’s rural medical service implementation with a focus on equitable distribution of doctors across the country. For this purpose, we analysed the distribution of all doctors, including rural service doctors, in health-care facilities across rural and remote areas of Ecuador in the public sector at the canton level for 2015 and 2019, by level of care (primary, secondary and tertiary). We used publicly available data from the Ministry of Public Health, the Ecuadorian Institute of Social Security and the Peasant Social Security. Our analyses show that two of every three rural service doctors are concentrated at the secondary level, while almost one in five rural service doctors, at the tertiary level. Moreover, cantons concentrating most rural service doctors were in the country’s major urban centres (Quito, Guayaquil, Cuenca). To our knowledge, this is the first quantitative assessment of the mandatory rural service year in Ecuador in its five-decade existence. We provide evidence of gaps and inequities impacting rural communities and present decision makers with a methodology for placement, monitoring and support of the rural service doctors programme, provided that legal and programmatic reforms come into place. Changing the programme’s approach would be more likely to fulfill the intended goals of rural service and contribute to strengthening primary health care
Comparison of inpatient psychiatric medication management in gender diverse youth with cisgender peers
No full textGender diverse (GD) youth, defined as transgender (TG) and nonconforming (NC) adolescents, have a 2- to 3-fold increased risk of having a mental health diagnosis, particularly a depressive or anxiety disorder, compared with cisgender (CG) peers.1,2 Additionally, psychologic distress is commonly reported in GD youths due to harassment, victimization, and bullying by peers.3,4 Approximately 30% to 50% of GD patients report serious psychologic distress leading to attempted suicide, with the highest risk in transmasculine patients.5-7 Mental health evaluations should be routine care for all adolescents.8 However, GD individuals often report stigma and discrimination in health care services secondary to lack of insurance coverage for gender-affirming care, and negative experiences with health care providers.3,9-11
Studies evaluating the treatment of psychiatric disorders in GD youth are limited. Hisle-Gorman et al12 conducted a large retrospective study assessing psychotropic prescribing in GD youth. Researchers identified 3754 military-dependent GD youth (ages <18 years) and matched them to CG siblings (N = 6603) to assess differences in mental health diagnoses, mental health visits, and outpatient psychotropic prescriptions. They found GD youth were approximately 5 times more likely to have a mental health diagnosis and at least 2 times more likely to use mental health services and be prescribed psychotropics.
Literature suggests that gender-affirming care, addressing psychologic, surgical, and hormonal therapies, is medically necessary to alleviate gender dysphoria and reduce psychiatric comorbidities.13-16 In the study by Hisle-Gorman et al,12 researchers additionally assessed the effects of gender-affirming hormone therapy (GAHT) on mental health outcomes in the TG subgroup.12 Among the 963 TG youth receiving GAHT, mental health care use did not significantly change after initiation of GAHT; however, psychotropic medication use increased in all categories except stimulants, migraine agents, and lithium.12
Psychotropic medications are not benign agents and can have short- and long-term effects in children and adolescents. Antidepressants have been associated with reduced growth velocity, reduced bone mineral density, and a potential risk for diabetes mellitus secondary to weight gain in pediatric patients.17 All antidepressants carry a black box warning for increased suicidality in adolescent patients.18 Additionally, antipsychotics have increased risks for metabolic syndromes, specifically hyperlipidemia, diabetes mellitus, and cardiovascular disease.19-22 Our study aims to compare psychotropic prescribing in GD youth to their CG peers with the same primary psychiatric diagnosis during an inpatient psychiatric hospitalization
Role of plant relatedness in plant–soil feedback dynamics of sympatric Asclepias species
Get PDFPlants affect associated biotic and abiotic edaphic factors, with reciprocal feedbacks from soil characteristics affecting plants. These two-way interactions between plants and soils are collectively known as plant–soil feedbacks (PSFs). The role of phylogenetic relatedness and evolutionary histories have recently emerged as a potential driver of PSFs, although the strength and direction of feedbacks among sympatric congeners are not well-understood. We examined plant–soil feedback responses of Asclepias syriaca, a common clonal milkweed species, with several sympatric congeners across a gradient of increasing phylogenetic distances (A. tuberosa, A. viridis, A. sullivantii, and A. verticillata, respectively). Plant–soil feedbacks were measured through productivity and colonization by arbuscular mycorrhizal (AM) fungi. Asclepias syriaca produced less biomass in soils conditioned by the most phylogenetically distant species (A. verticillata), relative to conspecific-conditioned soils. Similarly, arbuscular mycorrhizal (AM) fungal colonization of A. syriaca roots was reduced when grown in soils conditioned by A. verticillata, compared with colonization in plants grown in soil conditioned by any of the other three Asclepias species, indicating mycorrhizal associations are a potential mechanism of observed positive PSFs. This display of differences between the most phylogenetically distant, but not close or intermediate, paring(s) suggests a potential phylogenetic threshold, although other exogenous factors cannot be ruled out. Overall, these results highlight the potential role of phylogenetic distance in influencing positive PSFs through mutualists. The role of phylogenetic relatedness and evolutionary histories have recently emerged as a potential driver of plant–soil feedbacks (PSFs), although the strength and direction of feedbacks among sympatric congeners are not well-understood. Congeneric, sympatric milkweeds typically generated positive PSFs in terms of productivity and AM fungal colonization, suggesting the low likelihood of coexistence among tested pairs, with a strength of feedback increasing as the phylogenetic distance increases
Quality of Professional Interaction (Operational Performance)
Get PDFThis study utilized a mixed methods research design with sequential data collection to assess community stakeholder impressions of the Jackson County, MO Community Mental Health Fund personnel and operations. Survey questions asked if the organization was smoothly functioning, if the quality of personnel interactions was professional, and assessed how fund personnel availability, responsiveness and collaboration were experienced by community based stakeholders
Fatigue-Induced Neuromuscular Performance Changes in Professional Male Volleyball Players
Get PDFThe purpose of the present study was to assess pre-post practice changes in countermovement vertical jump (CVJ) force-time metrics and to determine the relationship between internal and external load variables within a cohort of professional male volleyball players. Ten elite athletes competing in one of the top professional European leagues participated in the present study. While standing on a uni-axial force plate, each athlete performed three CVJs immediately prior to the regular training session. Each athlete wore an inertial measurement unit (VertTM) through an entire practice from which the following external load metrics were obtained: Stress (i.e., an algorithm-derived metric used to quantify the percentage of high-impact movements), Jumps (i.e., the total number of jumps performed during the practice session), and Active Minutes (i.e., the total amount of time performing dynamic movements). Immediately post-practice, each athlete completed another set of three CVJs and reported their subjective measure of internal load using a Rating of Perceived Exertion (RPE) scale (Borg CR-10). While no statistically significant differences were observed in any of the force-time metrics examined in the present study pre-post practice (e.g., eccentric and concentric peak and mean force and power, vertical jump height, contraction time, countermovement depth), our findings indicate a strong positive association between RPE and Stress (r = 0.713) and RPE and Jumps (r = 0.671). However, a weak non-statistically significant correlation was observed between RPE and Active Minutes (r = −0.038), indicating that internal load seems to be more dependent on the intensity rather than the duration of the training session for this sport