32151 research outputs found
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Explainable artificial intelligence to identify follicles that optimize clinical outcomes during assisted conception
Get PDFFunding: S.H. is supported by the UKRI CDT in AI for Healthcare http://ai4health.io (EP/S023283/1). A.Ab. is supported by an NIHR Clinician Scientist Award (CS-2018-18-ST2-002). W.S.D. is supported by an NIHR Senior Investigator Award (NIHR202371).Infertility affects one-in-six couples, often necessitating in vitro fertilization treatment (IVF). IVF generates complex data, which can challenge the utilization of the full richness of data during decision-making, leading to reliance on simple ‘rules-of-thumb’. Machine learning techniques are well-suited to analyzing complex data to provide data-driven recommendations to improve decision-making. In this multi-center study (n = 19,082 treatment-naive female patients), including 11 European IVF centers, we harnessed explainable artificial intelligence to identify follicle sizes that contribute most to relevant downstream clinical outcomes. We found that intermediately-sized follicles were most important to the number of mature oocytes subsequently retrieved. Maximizing this proportion of follicles by the end of ovarian stimulation was associated with improved live birth rates. Our data suggests that larger mean follicle sizes, especially those >18 mm, were associated with premature progesterone elevation by the end of ovarian stimulation and a negative impact on live birth rates with fresh embryo transfer. These data highlight the potential of computer technologies to aid in the personalization of IVF to optimize clinical outcomes pending future prospective validation.Peer reviewe
Protocol for a meta-review on applied linguistics researchscape
Get PDFFunding: British Association for Applied Linguistics.Over the years, applied linguistics has evolved into an increasingly complex and interdisciplinary field. Accordingly, more diverse research methods are being used to address different topics in the field. Despite this conceptual complexity and methodological diversity, much of the existing research syntheses focus on one specific subfield or one particular research method, so there is a notable gap in our understanding of how applied linguistics as a whole is conceptualised and researched. This state-of-play meta-review, commissioned by the British Association for Applied Linguistics (BAAL), aims to systematically examine research syntheses in applied linguistics, focusing on key topics, methodologies, and research gaps. We will use a structured search strategy across four databases: Scopus, Web of Science, APA PsycINFO, and EBSCO. Forward and backward citation tracking will also be employed to identify additional relevant studies. This meta-review will use descriptive statistics (e.g., percentages, frequency counts) to summarise thematic and methodological trends and thematic analysis to identify and interpret patterns in the data. Additionally, an interactive evidence gap map on an open-access web database will be created using EPPI Mapper to make the data more accessible and visually informative.Peer reviewe
Breaking the symmetries of indistinguishable objects
Get PDFFunding: This work was supported by the Engineering and Physical Sciences Research Council EP/Y000609/1.Indistinguishable objects often occur when modelling problems in constraint programming, as well as in other related paradigms. They occur when objects can be viewed as being drawn from a set of unlabelled objects, and the only operation allowed on them is equality testing. For example, the golfers in the social golfer problem are indistinguishable. If we do label the golfers, then any relabelling of the golfers in one solution gives another valid solution. In this paper, we show how we can break the symmetries resulting from indistinguishable objects. We show how these symmetries induce symmetries of types built from indistinguishable objects, for example in a matrix indexed by indistinguishable objects. We then show how the resulting symmetries can be broken correctly and completely. As the method can be prohibitively expensive, we also study methods for breaking the symmetry only partially. In Essence, a high-level modelling language, indistinguishable objects are encapsulated in ‘unnamed types’. We provide an implementation to automatically break symmetries of unnamed types
Differential COVID-19 case ascertainment by age and vaccination status in Victoria, Australia : a serosurveillance and record linkage study
Get PDFFunding: The Victorian Department of Health commissioned and funded VIDRL to conduct this project.Objectives: To compare serological evidence of prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with linked coronavirus disease 2019 (COVID-19) case notification data in Victoria, Australia, and to determine in vitro SARS-CoV-2 neutralisation activity based on prior infection and vaccination history. Design, setting, participants: Four cross-sectional serological surveys were conducted between 30 June and 31 October 2022 (a period of Omicron BA.4/BA.5 dominance) using 1,974 residual serum samples obtained from the Victorian Infectious Diseases Reference Laboratory. Serological results were linked to COVID-19 case notification and vaccination data. Surrogate virus neutralisation testing was performed to obtain in vitro inhibition estimates by anti-nucleocapsid serostatus and COVID-19 vaccination history. Main outcome measures: Adjusted anti-SARS-CoV-2 spike and nucleocapsid seropositivity by sex, age and region of residence; adjusted proportion of cases notified by anti-nucleocapsid serostatus, age and number of COVID-19 vaccination doses received; adjusted percentage in vitro inhibition against wildtype and Omicron BA.4/BA.5 SARS-CoV-2 variants by anti-nucleocapsid serostatus and COVID-19 vaccination history. Results: The prevalence of anti-SARS-CoV-2 nucleocapsid antibodies was inversely proportional to age. In October 2022, prevalence was 84% (95% confidence interval [95% CI]: 75-93%) among 18-29-year-olds, compared to 39% (95% CI: 27-52%) among ≥ 80-year-olds. In most age groups, approximately 40% of COVID-19 cases appear to have been notified via existing surveillance mechanisms. Case notification was highest among individuals older than 80 years and people who had received COVID-19 vaccine booster doses. In vitro neutralisation of Omicron BA.4/BA.5 sub-variants was highest for individuals with evidence of both prior infection and booster vaccination. Conclusions: Under-notification of SARS-CoV-2 infections in the Victorian population is not uniform across age and vaccination strata. Seroprevalence data that give insights into case notification behaviour provide additional context for the interpretation of existing COVID-19 surveillance information.Peer reviewe
Eukaryotes expansion into non-marine habitats prohibited by nitrogen limitation during the mid-Proterozoic
Get PDFFunding: This project was funded by National Key Research and Development Program of China (2022YFF0800303), Fundamental Research Funds for the Hebei GEO University (QN25004), National Natural Science Foundation of China (4177020732), and National Natural Science Foundation of China Young Scientists Fund (42402199). EES acknowledges funding from a NERC Frontiers grant (NE/V010824/1).Persistently anoxic conditions and nutrient limitations in the mid-Proterozoic have been invoked to explain the delayed evolution and expansion of eukaryotes. However, limited information is so far available about nutrient availability in nonmarine habitats. To fill this knowledge gap, we conducted a multi-proxy study of Statherian strata from the Dagushi, Bingmagou, Baicaoping, and Puyu formations in the Xiong’er Basin, southern margin of the North China Craton (NCC). This set of rocks offers a rare opportunity to study nutrient availability along a gradient from nonmarine to marine conditions in the mid-Proterozoic. Our δ15N data suggest that nitrogen cycling was dominated by N2 fixation under nonmarine conditions. Hence, lacustrine waters were oligotrophic with regard to nitrogen. In contrast, nitrate (NO3−) appears to have been available in shallow marine waters. These findings suggest that oxygenated shallow marine margins were suitable for eukaryotes, but their radiation into nonmarine settings may have been N-limited.Peer reviewe
Genome analysis of multidrug resistant Enterococcus faecium and Enterococcus faecalis circulating among hospitalized patients in uMgungundlovu District, KwaZulu-Natal, South Africa
Get PDFFunding: This work was supported by the Antimicrobial Research Unit (ARU) and College of Health Sciences (CHS) of the University of KwaZulu-Natal. The National Research Foundation funded this study through the NRF Incentive Funding for Rated Researchers (Grant No. 85595), the NRF Competitive Grant for Rated Researchers (Grant no. 106063) and the DST/NRF South African Research Chair in Antibiotic Resistance and One Health (Grant No. 98342) awarded to professor S.Y. Essack. The South African Medical Research Council through the Self-Initiated Research (Sir) Grant also funded the WGS aspect of study.Background Vancomycin-resistant enterococci (VRE) are important pathogens categorized as high-priority bacteria in the Global Priority List of Antibiotic-Resistant Bacteria to Guide Research, Discovery, and Development of New Antibiotics published by the World Health Organization. The aim of this study was to determine the risk factors, resistance, virulence, mobilomes associated with multidrug-resistant and clonal lineages of Enterococcus faecium and faecalis circulating among hospitalized patients following the health system in South Africa, using whole genome sequencing (WGS). Methods A cross-sectional study was conducted during a two-month periods among hospitalized patients in 2017. Rectal swabs were collected from patients admitted to medical and surgical wards in an urban tertiary hospital, and a rural district hospital in uMgungundlovu district, South Africa. Enterococci were screened for vancomycin resistance on bile esculin azide agar supplemented with 6 mg/L of vancomycin and confirmation of VRE was done using ROSCO kits. Conventional and real-time PCR methods were used to ascertain the presence of VanA, VanB, VanC-2/3 and VanC-1 genes. All six multidrug-resistant Enterococcus faecalis and faecium selected were identified using multiplexed paired-end libraries (2 × 300 bp) with the Nextera XT DNA sample preparation kit (Illumina, San Diego, CA, USA) and genome sequencing was done using Illumina MiSeq instrument with 100× coverage at the National Institute of Communicable Diseases Sequencing Core Facility, South Africa. Antibiotic resistance genes, virulence factors, plasmids, integrons and CRISPR were characterized using RAST, ResFinder, VirulenceFinder, PlasmidFinder, PHAST and ISFinder respectively. Results Sequencing analysis revealed that these strains harbouring numerous resistance genes to glycopeptides (vanC[100%], vex3[100%], vex2[83,33%] and vanG[16,66%]), macrolides, lincosamides, sterptogramine B (ermB[33,32%], Isa[16,66%], emeA[16,66%]) and tetracyclines (tetM[33,32%]) in both district and tertiary hospitals. Multidrug efflux pumps including MATE, MFS and pmrA conferring resistance to several classes of antibiotics were also identified. The main transposable elements observed were in the Tn3 family, specifically Tn1546. Four single sequence types (STs) were identified among E. faecium in the district hospital, namely ST822, ST636, ST97 along with a novel ST assigned ST1386, while one lineage, ST29 was detected in the tertiary hospital. Conclusion The study reveals the genetic diversity and high pathogenicity of multidrug-resistant Enterococcus faecalis and faecium circulating among hospitalized patients. It underlines the necessity to implement routine screening of admitted patients coupled with infection control procedures, antimicrobial stewardship and awareness should be strengthened to prevent and/or contain the carriage and spread of multidrug resistant E. faecium and E. faecalis in hospitals and communities in South Africa.Peer reviewe
Investigation of transition metal-doped BaCe0.8Y0.2O3-δ cathodes for protonic ceramic fuel cells : microstructural and electrical properties
Get PDFProtonic ceramic cathodes have emerged as a vital component for enhancing the efficiency and performance of protonic ceramic fuel cells (PCFCs) due to their excellent protonic conductivity and intermediate operation temperature. In this work, the doping effect of transition metals in BaCe0.8X0.1Y0.1O3-δ (X = Ni, Co, and Cu, BCXY) perovskites was systematically investigated. The phase analysis via X-ray diffraction (XRD) studies confirmed the development of single-phase perovskite for all doped samples. Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM) were employed to examine the surface morphology, revealing clear and well-defined crystallites. TEM mapping further demonstrated the uniform dispersion of dopants, indicating successful synthesis. X-ray photoelectron spectroscopy (XPS) further validates the elemental composition and purity of the samples. The lowest area-specific resistance (ASR) values were obtained for BCCuY at 750 °C, measuring 0.21 Ω·cm2 in dry air and 0.17 Ω·cm2 in wet air. The activation energies in wet air atmosphere were found to be in the order of BCCuY (0.64 eV) < BCCoY (0.76 eV) < BCNiY (1.12 eV), within the temperature range of 600 to 750 °C, suggesting that BCCuY has the lowest activation energy and potentially better catalytic activity in these conditions. Considering these results, BCCuY perovskite shows promise as a protonic ceramic cathode for PCFCs. The long-term chemical compatibility evaluation was performed at 800 °C for 100 hrs, which showed that all three electrode materials are chemically compatible with BCZY electrolyte. This work shows the strategy of doping transition metals in BaCeO3-δ-type oxides could be of great interest for the successful development of novel oxygen electrodes for PCFCs.Peer reviewe
Identifying biases and the relevant statistical population : the case of the Loch Ness Monster
Get PDFFunding: Blink Films UK provided funding for some of the analyses.We used a database of Loch Ness Monster reports to show university level students how important it is to think about bias and the identification of the correct statistical population. The Loch Ness Monster reports database illustrates the importance of considering independence, inaccuracy and imprecision when considering data and how statisticians might handle anecdotes as data. Whilst the data is inappropriate for directly making inferences about Loch Ness Monsters, it may be appropriate for making inferences about the population of Loch Ness Monster reports.Peer reviewe
U−Pb geochronology and microstructural analysis of apatite within a Proterozoic crustal-scale shear zone, Outer Hebrides, NW Scotland
No full textFunding: Funding of fieldwork and sample collection from the University of Portsmouth is gratefully acknowledged.U–Pb apatite geochronology is increasingly recognized as a valuable tool for constraining the age of mid-crustal ductile shear zones. The crustal-scale Outer Hebrides Fault Zone (OHFZ) within the Laurentian foreland of the Scottish Caledonides has long been of uncertain age and tectonic significance. Earliest deformation within the OHFZ was associated with top-to-the-NW ductile thrusting that formed a belt of greenschist facies mylonites within host Archean−Paleoproterozoic basement gneisses. Previous estimates for the timing of thrusting vary between c. 1600 Ma and c. 430 Ma. The mylonitic fabrics are defined by a recrystallized assemblage of quartz + albite/oligoclase + sericite + actinolite + epidote + apatite ± calcite, consistent with deformation temperatures of 400–500°C and within the range of reported closure temperatures for Pb diffusion in apatite. U–Pb (LA−ICP−MS) dating of two texturally distinct apatite grain types within the mylonites has yielded ages mostly in the range c. 1100–900 Ma. The OHFZ is therefore interpreted as a Grenville–Sveconorwegian structure that formed during the tripartite collision of Laurentia, Baltica, and Amazonia and the assembly of Rodinia.Peer reviewe
Machine learning to predict interim response in pediatric classical Hodgkin lymphoma using affordable blood tests
Get PDFPurpose Response assessment of classical Hodgkin lymphoma (cHL) with positron emission tomography-computerized tomography (PET-CT) is standard of care in well-resourced settings but unavailable in most African countries. We aimed to investigate correlations between changes in PET-CT findings at interim analysis with changes in blood test results in pediatric patients with cHL in 17 South African centers. Methods Changes in ferritin, lactate dehydrogenase (LDH), erythrocyte sedimentation rate (ESR), albumin, total white cell count (TWC), absolute lymphocyte count (ALC), and absolute eosinophil count were compared with PET-CT Deauville scores (DS) after two cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine in 84 pediatric patients with cHL. DS 1-3 denoted rapid early response (RER) while DS 4-5 denoted slow early response (SER). Missing values were imputed using the k-nearest neighbor algorithm. Baseline and follow-up blood test values were combined into a single difference variable. Data were split into training and testing sets for analysis using Python scikit-learn 1.2.2 with logistic regression, random forests, naïve Bayes, and support vector machine classifiers. Results Random forest analysis achieved the best validated test accuracy of 73% when predicting RER or SER from blood samples. When applied to the full data set, the optimal model had a predictive accuracy of 80% and a receiver operating characteristic AUC of 89%. The most predictive variable was the differences in ALC, contributing 21% to the model. Differences in ferritin, LDH, and TWC contributed 15%-16%. Differences in ESR, hemoglobin, and albumin contributed 11%-12%. Conclusion Changes in low-cost, widely available blood tests may predict chemosensitivity for pediatric cHL without access to PET-CT, identifying patients who may not require radiotherapy. Changes in these nonspecific blood tests should be assessed in combination with clinical findings and available imaging to avoid undertreatment.Peer reviewe
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