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Mathematical Models for predicting CO2 Density and Viscosity for Enhanced Gas Recovery and Carbon Sequestration
Full text linkThere is limited work on mathematical correlations in place for predicting density and viscosity of supercritical carbon-dioxide (CO2), necessary for Enhanced Gas Recovery-Carbon Sequestration (EGR-CS) operations. In this work, three categories of mathematical correlations were developed by Split Regression Analytical method and validated using Equation of State (EOS) models for predicting density and viscosity of carbon-dioxide under supercritical conditions as expected in EGR-CS operation. The models range for application is for reservoir depths of 1000-1500m, 1600-5000m and beyond 5000m for both CO2 density and viscosity, which are ideal for carbon sequestration and covers depths of most gas reservoirs in Niger-Delta. The new "UDA-Model" matched with Peng Robinson and Soave-Redlich-Kwong (EOS) models at the tested reservoir conditions, with low Absolute Average Deviation. Application of these mathematical correlations on four depleted gas reservoirs in Niger Delta formations shows Relative Density Difference (RDD) and Relative Viscosity Difference (RVD) on CO2 and natural gas. CO2 densities at those depths range from 0.5-0.6g/cm 3 , 0.6-0.7g/cm 3 , and 0.7-0.8g/cm 3 respectively while the viscosities range from 0.05-0.06cP, 0.06-0.07cP, and 0.07-0.08cP respectively. The results promise smoother displacement of natural gas by CO2 during EGR-CS operations
Internet-based group compassion-focused therapy for Swedish young people with stress, anxiety and depression: a pilot waitlist randomized controlled trial
Full text linkIntroduction: Compassion-focused therapy (CFT) has shown promising outcomes for young people, but research on CFT for this population remains limited. This study aims to evaluate the feasibility and acceptability of a seven-session, therapist-led, internet-based group CFT for young people, and to investigate its preliminary effects. Methods: A two-arm pilot randomized controlled trial (RCT) was conducted. The study included 42 participants (aged 15–20), experiencing mild to moderate stress, anxiety, or depression, most of whom (90%) were female. In the intervention group, 22 participants were included in the intention-to-treat (ITT) analysis. The trial was registered at ClinicalTrials.gov (NCT05448014). Results: The intervention group had low attrition and moderate attendance, with 77% completing four or more modules. No adverse events were reported, and participants generally expressed satisfaction with the intervention. Linear regression models showed preliminary between-group differences in two variables. Depressive symptoms increased post-intervention for individuals in the intervention group compared to the waitlist (WL) group (p = 0.002). Self-compassion improved in the intervention group (p = 0.023). These patterns were consistent among participants who completed more than two sessions. Within-group analyses indicated moderate, significant improvements in stress, self-compassion and compassion from others. Discussion: These preliminary results suggest that CFT is feasible and acceptable and may offer benefits for young people, particularly by enhancing self-compassion and compassion for others. The observed increase in depressive symptoms in the intervention group, despite improvements in self-compassion, warrants further investigation. Larger studies are needed to confirm these preliminary results and to better understand the underlying mechanisms
Genomic Characterisation of Novel Veterinary Pathogens: Anaplasma & Bartonella species
Full text linkBackground: Bartonella sp. and Anaplasma phagocytophilum (Ap) are vector-bornebacterial pathogens with significant veterinary and public health implications. WhileBartonella species persist in the bloodstream of various mammals causing long termbacteraemia, Ap is an intracellular pathogen causing granulocytic anaplasmosis.Despite their importance, genomic data on novel Bartonella species and UK Apstrains remains limited. Additionally, the low abundance and intracellular nature ofAp complicate direct sequencing from host tissues. Expanding genomic resourcesand refining enrichment methods are essential for improving pathogencharacterisation and understanding host-pathogen interactions.Objectives: Characterise a novel species of Bartonella, generate the first completegenome representations of Anaplasma phagocytophilum (Ap) isolated in the UK anddevelop optimised enrichment methodologies for high-resolution sequencing of Apdirectly from infected host tissue.Methods: Three Bartonella strains isolated from field voles (Microtus agrestis) andseven Ap strains isolated from domestic ruminants were sequenced using Illuminashort-read and Oxford Nanopore long-read systems. Genomic analyses includedphylogenetic reconstruction based on concatenated core gene alignments,pangenomic profiling, and average nucleotide identity calculations. Enrichmentstrategies encompassing differential lysis (Molzym), CpG methylation depletion(NEB), biotinylated RNA bait capture (Agilent SureSelect), and adaptive sampling(ONT) were systematically evaluated on roe deer spleen samples infected with Ap.Alignment files were investigated to assess genome coverage and identify capturebiases. An optimised approach was applied to the spleen of an Ap-infected commonshrew (Sorex araneus) with the aim of characterising the currently uncultured,genetically divergent small mammal-associated (ecotype III) strain of the species.Results: Whole genome analyses identified the three Bartonella strains as a novellineage 3 species, proposed as Bartonella bennettii most notably containing achromosomally integrated vbh/TraG type IV secretion system of plasmid origin.Phylogenetic analysis of UK Ap isolates placed them within the European ecotype Icluster, while revealing potential subdivisions. The pangenome identified core andaccessory genes, with ANI values suggesting species boundaries within Ap.Enrichment protocols combining Monarch HMW DNA extraction and NEBmicrobiome depletion yielded optimal pathogen representation. Gap analysishighlighted capture biases and the potential of the technology to capture completeAp genomes, especially in the context of long read systems. The small mammal-associated ecotype III strain was partially captured with non-specific ecotype I baitsidentifying the limits of the capture technology. Linkage analysis of groEL genessupported existing ecotype classifications, whereas whole genome phylogeneticsindicated potential reclassification into four epidemiologically separated species in aglobal context.Conclusions: B. bennettii was characterised through genomic analyses, providinginsights into the diversity and evolution of virulence factors in the Bartonella genus.Additionally, the first complete Ap genomes from the UK were generated, providinginsights into genomic diversity and phylogenetic relationships. Optimised enrichmentstrategies were developed for high-resolution metagenomic sequencing, overcomingchallenges posed by low bacterial loads and complex metagenomic samples. Wholegenome analysis suggests the European ecotypes are representative of global Apdiversity, with ANI supporting the existence of four epidemiologically separatespecies within Ap. Continued genomic characterisation is crucial for understandingthe drivers of host specificity, zoonotic potential, and epidemiological dynamicswithin these diverse blood-borne parasites
Treatment Effect Measures Under Nonproportional Hazards
No full text‘Treatment effect measures under nonproportional hazards’ by Snapinn et al. (Pharmaceutical Statistics, 22, 181–193) recently proposed some novel estimates of treatment effect for time‐to‐event endpoints. In this note, we clarify three points related to the proposed estimators that help to elucidate their properties. We hope that their work, and this commentary, will motivate further discussion concerning treatment effect measures that do not require the proportional hazards assumption
Uncovering the Unusual Inhibition Mechanism of a Trypanosome Alternative Oxidase Inhibitor Displaying Broad-Spectrum Activity against African Animal Trypanosomes
Full text linkThe glucose-dependent respiration of bloodstream forms of the parasite Trypanosoma brucei depends on an unusual and essential mitochondrial electron-transport system, consisting of glycerol-3-phosphate dehydrogenase and the trypanosome alternative oxidase (TAO). We report here the discovery of an allosteric inhibitor of TAO that displays highly potent activity (EC50 values in the range 1–20 nM) against the important veterinary pathogens T. b. brucei, Trypanosoma evansi, Trypanosoma equiperdum, and Trypanosoma congolense, i.e., >5-fold greater potency than the standard drugs. The methylene-linked 2-methyl-4-hydroxybenzoate 2-pyridinyldiphenylphosphonium derivative (1) was the best inhibitor of recombinant TAO (IC50 = 1.3 nM) via a noncompetitive/allosteric mechanism (Ki = 3.46 nM). Remarkably, X-ray crystallography showed that 1 was bound to a site of TAO ∼25 Å from the catalytic pocket. Although 1 demonstrated good safety toward mammalian cells in vitro (selectivity index >2300), it did not fully clear parasitemia in experimental animals, attributable to a high hepatic clearance
A scoping review of the feasibility, usability, and efficacy of digital interventions in older adults concerning physical activity and/or exercise
Full text linkBackground: The global population is aging, leading to significant health challenges among older adults, such as reduced muscle mass, increased risks of dementias, and chronic diseases. Physical activity (PA) is crucial for maintaining health and wellbeing in this demographic, yet participation tends to decrease with age due to various barriers. Digital technologies, including mobile health (mHealth) interventions, show promise in promoting PA among older adults, though their adoption remains limited due to intrinsic and extrinsic challenges. Objectives: This scoping review aimed to systematically map existing evidence on digital PA interventions for older adults, assessing feasibility, usability, and efficacy, whilst providing recommendations for future research and practice. Eligibility criteria: Original investigations concerning digital interventions in older adults (≥60 years of age) focusing on physical activity and/or exercise were considered. Sources of evidence: Four electronic databases [MEDLINE, CINAHL Ultimate, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL)] were searched. Methods: A scoping review was conducted using the scoping review methodological framework. Review selection and characterisation were carried out by two independent reviewers. Results: The 34 included studies were published between 2005 and 2023 across Europe, North America, Asia, and Oceania. Participants varied from healthy to frail individuals, with some diagnosed with dementia or cognitive impairment. Interventions were most commonly delivered via exergames, tablet apps, and videoconferencing. The most common exercise program type was multicomponent. Most studies assessed efficacy, feasibility, and usability, with many using a combination of these measures. Reminders were commonly utilised to enhance engagement through various digital and non-digital methods. Conclusion: There was a notable lack of mobile health (mHealth) studies in the literature, with most research focusing on exergame and tablet interventions. More research on smartphone apps, particularly for muscle strengthening, is needed, and the growing ease of app development may drive innovation and research. Digital interventions are generally feasible, usable, and effective for older adults, offering a promising, scalable approach for promoting PA. This review identified several valuable lessons from the existent literature for future developments
Approaches to Automatic Classification, Detection and Segmentation of Breast Arterial Calcification Using Deep Learning
No full textObjective: Cardiovascular disease (CVD) is the leading cause of premature death in the United Kingdom with one type, coronary artery disease, killing more than twice as many women as breast cancer. Recently, researchers have noted that breast arterial calcification (BAC), which is regularly observed as an incidental finding on mammograms, could be used to risk-stratify women for CVD. However, identifying BAC is known to be a tedious, expensive and time-consuming process. Thus, this paper investigates deep learning models for BAC classification, object detection and segmen-tation. Methodology: A dataset, annotated under the guidance of two consultant radiologists, was created using data augmentation. This was used to evaluate several alternative deep learning models. Results: A modified ResNet22 classification network achieved a test accuracy of 80%, indicating that this method could be used as a flag for the presence or absence of BAC. We also used this network for feature extraction in a YOLOv4 BAC object detection network. Despite improving on a recent similar study, this latter network performed poorly with very low average precision scores at several thresholds. More promising was our DeepLabv3+-based BAC segmentation network which reached similarly high global accuracy scores to three recent studies and a BFScore of over 70% specifically for BAC. It also performed satisfactorily on an unseen dataset. Conclusions: These results show the potential for using classification and segmentation models as part of a pipeline for detecting BAC
Gender-responsive procurement: a systematic literature review
Full text linkPurpose (limit 100 words) This paper synthesises the gender-responsive procurement literature from a range of academic disciplines and aims to identify the trajectory, methods, country focus and theoretical foundations of research in this area and to generate themes that relate to activities within a model that incorporates macro-environmental, as well as buyer and supplier perspectives and the interactions between them. Design/methodology/approach (limit 100 words) A multi-disciplinary systematic literature review was conducted, using the Denyer & Tranfield (2009) approach, analysing 88 peer-reviewed journal articles and a Social Dominance Theory lens was adopted in order to extend the analysis beyond the traditional boundaries of the procurement field. Findings (limit 100 words) The analysis establishes that there are systemic inequalities in some of the processes and activities that affect women-owned businesses from fully engaging in procurement opportunities and that macro-initiatives have yielded limited and uneven success. The study develops a comprehensive and holistic conceptual framework that integrates multidisciplinary insights and highlights persistent structural and systemic barriers to gender equity in procurement. Originality/value (limit 100 words) This research contributes a novel, theory-informed synthesis of gender-responsive procurement literature, spanning a range of academic disciplines and using Social Dominance Theory to generate insights into inequities within the procurement field. The conceptual framework and identified research gaps provide a robust platform for future inquiry and practice-based innovation in gender-responsive procurement
The foundational role of sound quality for understanding demonstratives
No full textThis paper explores the role of sound quality in the interpretation of demonstratives, arguing that their function is deeply connected to acoustic properties and human auditory perception. Drawing on research from psychoacoustics, sound localization, and philosophical and linguistic theories, I suggest that demonstratives are rooted in fundamental mechanisms of auditory cognition. The discussion begins with an examination of echolocation in bats, introducing the concept of meta-acoustic awareness – an ability to adjust vocal signals based on expected environmental interactions. I contend that what is special about echolocation is that it is self-directed. The vocal calls of humans, however, are fundamentally other-directed. I argue that other-directed meta-acoustic awareness is the basis for demonstrative reference. Demonstratives, such as “this” and “that,” function as indexicals requiring contextual information to be meaningful. However, their phonetic properties exhibit a universal pattern: proximal demonstratives tend to feature higher-frequency vowels, while distal demonstratives contain lower-frequency vowels. I argue that this contrast is not arbitrary but reflects an evolved sensitivity to acoustic cues that facilitate spatial orientation. By revisiting Bertrand Russell’s theory of egocentric particulars, I demonstrate that his insights on perception and reference anticipated key aspects of modern psychoacoustics. His emphasis on the physical reality of verbal utterances aligns with findings in sound symbolism, which suggest that the frequency of speech sounds conveys spatial relationships. Additionally, I explore evidence from child language acquisition and animal communication, showing that sound frequency influences reference and localization across species. Ultimately, I propose that demonstratives evolved within an auditory framework that exploits human sensitivity to spatially distributed sound patterns. This perspective challenges traditional semantic theories by grounding demonstratives in an embodied, perceptual system that integrates speech with spatial cognition. Understanding demonstratives as products of sound-based reference provides a new lens for analyzing linguistic structure and its cognitive underpinnings
Small sample pipeline DR defect detection based on smooth variational autoencoder and enhanced detection head faster RCNN
Full text linkThe safe operation of gas pipelines is crucial for the safety of residents’ lives and property. However, accurately detecting defects within these gas pipelines is a challenging task. To improve the accuracy of defect detection in pipeline DR images with small sample sizes, we propose an enhanced Faster RCNN model based on a Smooth Variational Autoencoder and Enhanced Detection Head (S-EDH-Faster RCNN). This model leverages a smooth variational autoencoder to reconstruct features and enhances classification scores through an improved detection head, thereby boosting overall detection accuracy. In detail, to address the issue of scarce training samples for new categories, we design a smooth variational autoencoder to reconstruct features that better fit the distribution of training data. Furthermore, to refine classification precision, we present an enhanced detection head that incorporates a convolutional block attention-based center point classification calibration module, which strengthens classification-related portions of the RoI features and adjusts classification scores accordingly. Finally, to effectively learn characteristics of novel class samples, we introduce an adaptive fine-tuning method that adaptively updates key convolutional kernels during the fine-tuning stage, enabling the model to generalize better to novel classes. Experimental results demonstrate that our approach achieves superior detection performance over state-of-the-art models on both the home-made PIP-DET dataset and the publicly available NEU-DET dataset, demonstrating its effectiveness
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