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Factors influencing dropout and retention among autistic students in universities: a meta-synthesis of qualitative studies involving autistic individuals
Get PDFA trackable trinuclear platinum complex for breast cancer treatment.
Get PDFCancer remains a leading cause of death, with triple-negative breast cancer (TNBC) being particularly significant due to limited treatment options. As such, there is interest in anticancer polynuclear platinum(II) complexes, attributed to their unique DNA-binding modes and potential against therapy-resistant cancer phenotypes. However, a persistent challenge with polynuclear compounds is their lack of cellular trackability, hindering their effectiveness and monitoring in clinical settings. Here, we report the preparation of a new azide-appended trinuclear platinum complex, N3-TriplatinNC, and characterize its DNA-targeting, cytotoxicity, and topoisomerase relaxation properties from the nanoscale to the macroscale. Using single-molecule biophysics and in-liquid atomic force microscopy, N3-TriplatinNC was identified as a powerful DNA recognition agent with remarkable potential towards the TNBC cell line, MDA-MB-231. Installation of the azide handle on the polynuclear complex was achieved using a first-in-class approach to produce a complex that retained analogous biological activity to the parent TriplatinNC. Importantly, the azide handle facilitates in situ click chemistry for tracking cellular localization, with subsequent xenograft studies demonstrating in vivo antitumoural potential
Dietary differentiation between sympatric ecotypes of Astatotilapia calliptera from Lake Masoko (Kisiba), Tanzania revealed by metabarcoding
Get PDFSympatric speciation is defined as the formation of new species in the absence of geographic barriers, but the genomic and life history strategy mechanisms underpinning sympatric speciation are still far from clear. It has recently been discovered that the cichlid fish Astatotilapia calliptera from crater Lake Masoko in Tanzania have diverged sympatrically into littoral (shallow water) and benthic (deep water) ecotypes, which differ in head and pharyngeal jaw morphology. Carbon stable isotope analysis has also broadly indicated trophic differentiation between ecotypes. Here, we explore trophic niche divergence on a finer scale, using metabarcoding of stomach contents. A combination of the mitochondrial COI region and 18S V4 region from the eukaryotic nuclear small subunit ribosomal DNA was used to target macroinvertebrate and broader eukaryotic taxonomic diversity, respectively, revealing dietary divergence between the ecotypes. Large proportions of Arthropoda (dipterans and copepod) were found in both ecotypes, indicating some food sources common to both microhabitats. However, gut contents of benthic A. calliptera individuals were characterized by an abundance of annelids and diatoms, while Lepidoptera, mayflies, fungi, freshwater mussels, and bivalves were common in littoral ecotypes. The variation observed in the dietary contents of the ecotypes indicates the presence of resource partitioning, facilitating adaptation to unique feeding strategies
Exploring the Effects of Merger and Acquisitions Activities on Employee Turnover Rate in High-Tech Firms
No full textIn the high-tech industry, mergers and acquisitions (M&As) are widely used as a pathway to execute their strategic plans and maintain competitiveness in rapidly evolving markets. However, the integration of diverse corporate cultures during M&A deals can escalate employee dissatisfaction and contribute to increased turnover rates. There is an abundance of theoretical discourse in the literature concerning the implications of M&As for employee experiences; however, it falls short in providing robust empirical evidence for practitioners. We investigate the impact of M&A activities on employee turnover rates in high-tech firms to address this gap. Utilising longitudinal data from 1999 to 2023, we find that increased M&A activities in high-tech companies are associated with higher employee turnover. Our study also identifies that advertising and R&D expenditures, as well as the size of top management, diminish the contribution of M&A activities to employee turnover. Conversely, enhanced asset efficiency amplifies the contribution of M&A activities to employee turnover
Ellipsoid zone reflectivity as a functional imaging biomarker for age-related macular degeneration: a MACUSTAR study report
Get PDFThis study evaluated the functional relevance of relative ellipsoid zone reflectivity (rEZR) on spectral-domain optical coherence tomography as a structural biomarker for retinal integrity, focusing on its association with retinal function. Participants with age-related macular degeneration (AMD) and controls from the MACUSTAR study underwent functional testing, including mesopic fundus-controlled perimetry, best-corrected visual acuity, low-luminance visual acuity, low-luminance deficit, Moorfields Acuity Test, and Pelli-Robson contrast sensitivity, along with spectral-domain optical coherence tomography imaging. Structural and functional data were analyzed globally and spatially aligned for topographic analysis. Linear-mixed effects models, adjusted for age, sex, and eccentricity of the rEZR, assessed associations between rEZR and functional metrics. A total of 275 eyes (early AMD, n = 34; intermediate AMD, n = 152; late AMD, n = 36; controls, n = 53) from 275 participants (mean ± standard deviation age: 71.1 ± 7.2 years; 63.3% female) were included. In global analyses, rEZR was associated with the mean average threshold in mesopic fundus-controlled perimetry (coefficient estimate 0.0492, 95% confidence interval 0.0190–0.0794, p = 0.0015), low-luminance visual acuity (coefficient estimate − 0.0015, 95% confidence interval − 0.0026 to − 0.0004, p = 0.0092), Moorfields Acuity Test (coefficient estimate 0.0092, 95% confidence interval − 0.0022 to − 0.0001, p = 0.0285), and Pelli-Robson contrast sensitivity (coefficient estimate 0.0030, 95% confidence interval 0.0015–0.0045, p = 0.0001). Topographic analysis further revealed an association of rEZR with mesopic retinal sensitivity (coefficient estimate 0.0065, 95% confidence interval 0.0026–0.0104, p < 0.0001). Higher outer retinal reflectivity is linked to better retinal function in AMD and controls, supporting its potential as a biomarker for retinal integrity and function
Energy scale and resolution for anti-kt jets with radius parameters R = 0.2 and 0.6 measured in proton-proton collisions at s = 13 TeV with the ATLAS detector
Get PDFJets with different radius parameters R are an important tool for probing quantum chromodynamics processes at different angular scales. Jets with small R = 0.2 are instrumental in measurements of the substructure of largeR jets resulting from collimated hadronic decays of energetic W, Z, and Higgs bosons, top quarks, and of potential new resonances. This paper presents measurements of the
energy scale, resolution, and associated uncertainties of jets with radius parameters R = 0.2 and 0.6, obtained using the ATLAS detector. The results are based on 37 fb−1 of proton– proton collision data from the Large Hadron Collider at a centre-of-mass energy of √s = 13 TeV. A new in situ method for measuring jet energy scale differences between data and Monte Carlo simulations is presented. The systematic uncertainties in the jet energy scale for central jets (|η| < 1.2) typically vary from 1% to about 5% as a function of |η| at very low transverse momentum, pT, of around 20 GeV for both R = 0.2 and 0.6 jets. The relative energy resolution
ranges from (35 ± 6)% at pT = 20 GeV to (6 ± 0.5)% at pT = 300 GeV for central R = 0.2 jets, and is found to be slightly worse for R = 0.6 jets. Finally, the effect of close-by hadronic activity on the jet energy scale is investigated and is found to be well modelled by the ATLAS Monte Carlo simulations
Mechanisms of adhesion increase in wet sanded wheel–rail contacts—a DEM-based analysis
Get PDFIn railways, problems in braking and traction can be caused by so-called low-adhesion conditions. Adhesion is increased by sanding, where sand grains are blasted towards the wheel–rail contact. Despite the successful use of sanding in practice and extensive experimental studies, the physical mechanisms of adhesion increase are poorly understood. This study combines experimental work with a DEM model to aim at a deeper understanding of adhesion increase during sanding. The experimentally observed processes during sanding involve repeated grain breakage, varying sand fragment spread, formation of clusters of crushed sand powders, plastic deformation of the steel surfaces due to the high load applied and shearing of the compressed sand fragments. The developed DEM model includes all these processes. Two types of rail sand are analysed, which differ in adhesion increase in High-Pressure Torsion tests under wet contact conditions. This study shows that higher adhesion is achieved when a larger proportion of the normal load is transferred through sand–steel contacts. This is strongly influenced by the coefficient of friction between sand and steel. Adhesion is higher for larger sand grains, higher sand fragment spread, and higher steel hardness, resulting in less indentation, all leading to larger areas covered by sand
The impact of energy prices on consumers: a tale of two crises
Get PDFTwo exogenous events, coupled with substantial data on household electricity and gas usage, enable us to examine detailed consumption effects of recent rises in energy prices in Britain resulting from the Russia-Ukraine conflict. We isolate two groups of consumers with similar characteristics, all initially on fixed price tariffs. One group, forcibly moved to variable price tariffs, suffered the price shock, the others remained on fixed price tariffs. Our difference-in-differences framework captures the impacts on the former group, finding significant negative consumption effects, particularly regarding gas usage. Differing effects across richer and poorer households are revealed, the poorest greatly reducing consumption
220–325 GHz all-photopolymer Bragg horn antennas towards eco-friendly terahertz applications
Get PDFThis paper presents the development of the world’s first high-gain, all-photopolymer Bragg horn antennas explicitly designed for the WR-3.4 band (220–325 GHz), marking a groundbreaking advancement in terahertz (THz) antenna technology. Unlike conventional metallic horn antennas, which suffer from conductor losses and manufacturing complexity, this innovative design utilizes eco-friendly photopolymer materials and additive manufacturing, achieving a fractional bandwidth of 38.5% that fully covers the WR-3.4 band. The proposed antenna achieves a measured peak gain of 28.98 dBi at 300 GHz, with a return loss better than − 20dB across the band and a consistent half-power beamwidth (HPBW) of ~ 5°, ensuring precise directivity and minimal sidelobe interference. By employing a novel horn-type adapter for seamless mode conversion from TE10 to the fundamental HE11 mode, the design significantly enhances coupling efficiency and reduces signal loss. Additionally, fabrication costs can be reduced by over 50% compared to traditional metallic designs, while maintaining repeatability and enabling rapid prototyping. As the first demonstration of photopolymer-based antennas achieving such high gains in the 220–325 GHz THz spectrum, this work establishes a new benchmark in THz antenna technology, providing an eco-friendly, cost-effective, and high-performance solution for high-speed communication, medical diagnostics, security imaging, and spectroscopy applications
The impact and cost-effectiveness of pulse oximetry and oxygen on acute lower respiratory infection outcomes in children in Malawi:a modelling study
Get PDFBACKGROUND: acute lower respiratory infections (ALRIs) are the leading global cause of post-neonatal death in children younger than 5 years. The impact, cost, and cost-effectiveness of routine pulse oximetry and oxygen on ALRI outcomes at scale remain unquantified. METHODS: We evaluate the impact and cost-effectiveness of scaling up pulse oximetry and oxygen on childhood ALRI outcomes in Malawi using a new and detailed individual-based model, together with a comprehensive costing assessment for 2024 that includes both capital and operational expenditures. We model 15 scenarios ranging from no pulse oximetry or oxygen (null scenario) to high coverage (90% pulse oximetry usage and 80% oxygen availability) across the health system. Cost-effectiveness results are presented in incremental cost-effectiveness ratios (ICERs) and incremental net health benefits (INHBs) using a Malawi-specific cost-effectiveness threshold of US35 (33-36) per DALY averted and $924 (887-963) per death averted. The INHB is 40 200 (37 300-43 100) net DALYs averted. INTERPRETATION: Pulse oximetry and oxygen are complementary cost-effective interventions in Malawi, where health expenditure is low, and should be scaled up in parallel. FUNDING: UK Research and Innovation, Wellcome Trust, Department for International Development, EU, Clinton Health Access Initiative, and Unitaid
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