34028 research outputs found
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Power relations and role boundaries between community first responders and ambulance clinicians in England: a qualitative study
No full textPower relations between clinical volunteers and professionals within health services constitute a key determinant of role relationships and boundaries. Community First Responders (CFRs) are trained lay volunteers who respond to emergencies, interacting with patients and ambulance professionals. We aimed to explore the power relationships between CFRs and ambulance clinicians. We conducted 40 in-depth interviews with 4 ambulance clinicians, 21 CFRs and 15 CFR-leads from six ambulance services in England. Thematic analysis, guided by theories of subordination and boundary work, enabled the identification of themes and subthemes. The analysis revealed experiences of power relations, hierarchy and negotiations of role boundaries, characterised by subordination of CFRs and development of collaborative relationships between ambulance clinicians and CFRs. A collaborative relationship was established when clinicians recognised the voluntary nature of CFR roles and their significant contributions to ambulance services. Ambulance clinicians had the professional power to influence these relationships and negotiations of role boundaries. Power dynamics between professional ambulance clinicians and volunteer CFRs affect their relationship and CFR roles. These power relations were consistent with subordination and role boundaries and demonstrated how power theories relate to CFRs.</p
Permutation-Invariant Polar Harmonic Pooling for Point-based Neural Networks
No full textPoint-based learning methods have recently gained significant attention for point cloud data analysis. These neural networks typically consist of a permutation-equivariant backbone network for feature extraction, a symmetric global pooling operation for feature aggregation, and a permutation-invariant classification or regression head. Most of the prior work has focused on improving the equivariant backbone while the global pooling operation, crucial for effective feature summarization has remained relatively underexplored. In this paper, we introduce Polar Harmonic Pooling (PHP), a novel symmetric global pooling method that leverages polar harmonic transforms to aggregate point cloud features. Unlike traditional pooling methods that rely on simple statistical measures, PHP captures global frequency patterns across the point set. This approach yields a more expressive and compact representation by encoding both spatial structure and frequency domain characteristics in polar coordinates. We evaluate PHP on both classification and regression tasks. Experimental results show that PHP enhances accuracy, reduces the number of parameters in the invariant classification or regression head, and helps reducing overfitting when compared to standard statistical pooling methods.</p
Synthesis of Ketones and Mono-fluoro Ketones via Boron Enolates Formed by Substitution of Esters with Benzylboronic Esters
No full textBenzylboronic esters can be deprotonated using LiTMP and engaged in useful C-C bond-forming processes. Here we report that they undergo acylation with esters. We also report a fluorinative coupling reaction performed through nucleophilic substitution of a lithiated benzylboronic ester with an ester, and trapping of the resultant boron enolate with the fluorinating agent NFSI.</p
Possible barriers to the effective use of practical work in school science
No full textOpinion-based article on the effective use of practical work.Practical work can play a very important role in the teaching and learning process in school science in contributing towards the development of students’ understanding of scientific processes and concepts, as well as in generating a positive attitude towards science in general. The purpose of this article is to identify barriers that hinder the effective use of practical work in secondary school science and to consider approaches that might help to overcome those barriers. The article distinguishes between barriers relating to resources and assessment and those that relate to teachers and technicians.</p
Transmission dynamics of Klebsiella pneumoniae in a neonatal intensive care unit in Zambia before and after an infection control bundle
No full textBackground: Klebsiella pneumoniae is a leading cause of neonatal sepsis in low-and middle-income countries, with antimicrobial resistance (AMR) significantly contributing to associated mortality. Infection prevention and control (IPC) interventions effectively reduced healthcare-associated infections and significantly decreased neonatal mortality in the Sepsis Prevention in Neonates in Zambia (SPINZ) study. Here we use whole genome sequencing to explore the impact of an IPC intervention on K. pneumoniae strains and transmission dynamics responsible for sepsis in a Zambian neonatal unit.Methods and Findings: Blood culture isolates were collected during the SPINZ study, including a 7-month baseline period and 12 months following implementation of a low-cost IPC bundle. Bacterial isolates were sequenced (using Illumina), assembled, and characterised in terms of lineage, AMR determinants, and polysaccharide antigens (using Kleborate and Kaptive). High-quality genome assemblies were obtained for 411 neonatal K. pneumoniae infections. The K. pneumoniae population was diverse, comprising 24 unique STs, but dominated by ST307 (69.3%, n=285). Nearly all isolates (99.0%) carried extended spectrum beta-lactamases, but few carried carbapenemases (2.7%). Probable transmission clusters were identified using single-linkage clustering with pairwise distance thresholds of ≤4 weeks and ≤10 single nucleotide variants (SNVs) between isolates. Most infections (95.6%) were associated with clusters, ranging in size from 2–202 patients and spanning durations of 2–232 days. Most K. pneumoniae (n=228, 70%) were isolated during the 7-month baseline period and formed six clusters, including one cluster of >200 neonates infected with ST307, which was interrupted by the IPC implementation. Novel clusters emerged during the post-intervention period, including additional STs and distinct ST307 lineages (unrelated to the pre-intervention cluster), but also ST2004 and ST101 clusters that were genetically indistinguishable from those detected pre-intervention.Conclusions: In this neonatal unit, K. pneumoniae sepsis was mostly attributable to nosocomial transmission clusters, including a large and sustained outbreak of ST307 affecting >200 neonates over eight months. Transmission of all strains was periodically suppressed by an IPC bundle; however not all strains were eliminated, and some were able to re-emerge later to re-establish infection and transmission, alongside newly introduced strains that formed additional transmission clusters.Some clusters were associated with rapid onset of disease (within 2 days of admission) and others with delayed onset, suggesting different sources of contamination (e.g. reagent vs environmental). These findings reinforce the need for sustained IPC efforts, and better understanding of environmental reservoirs of opportunistic pathogens in neonatal units to inform such efforts.</p
Contribution of nosocomial transmission to Klebsiella pneumoniae neonatal sepsis in Africa and South Asia: a meta-analysis of infection clusters inferred from pathogen genomics and temporal data
No full textBackground: Klebsiella pneumoniae is the leading cause of sepsis among neonates in low- and middle-income countries (LMICs) in Africa and Asia, contributing substantially to the overall burden of antimicrobial resistant (AMR) infections and mortality among neonates globally. Pathogen sequencing has been used to investigate case clusters and confirm nosocomial transmission in a small number of neonatal units. Here we utilise pathogen sequence data to estimate the fraction of K. pneumoniae neonatal sepsis attributable to nosocomial transmission in African and South Asian countries.Methods and Findings: We estimated the proportion of invasive K. pneumoniae disease involved in nosocomial transmission clusters in a given neonatal unit, using single-linkage clustering based on pairwise temporal and genetic distances estimated from bacterial whole-genome sequences. Analysing 1,523 K. pneumoniae isolated from 27 units in 13 countries in Africa and South Asia between 2013 and 2023, we inferred 156 nosocomial transmission clusters, ranging from 2 to 188 neonates each (83 of the clusters comprised ≥3 cases). Overall, we estimated that 1,035 neonatal infections (68.0%) were part of nosocomial transmission clusters. Excluding the first infection in each cluster as a potential index case, we estimate at least 879 (57.7%) infections were acquired via nosocomial transmission. Sensitivity analyses showed that results were robust to the choice of genetic distance estimation methods and thresholds used to define clusters, and cluster estimates were stable over temporal distance thresholds ranging from 2 to 8 weeks. Isolates were mostly extended-spectrum beta-lactamase (ESBL) producers (90.9%) and included 172 multi-locus sequence types (STs). Fourteen STs were associated with transmission clusters at multiple units and these were collectively responsible for two-thirds of all infections. Clustered isolates compared with singletons were more likely to carry carbapenemase genes (19.9% vs 10.2%, P = 0.003) or ESBL genes (94.2% vs 81.8%, P Conclusions: Nosocomial transmission contributes to a substantial proportion of K. pneumoniae sepsis in neonatal care units in Africa and South Asia. Reducing transmission within these settings through improved infection prevention and control and other measures could substantially reduce the neonatal sepsis burden.</p
Exploring Pyrazolidinone and Pyrazolidinedione Scaffolds for Alzheimer's Therapy: Multitarget COX-2 Inhibitors with Anti-Amyloid β, Anti-Tau, Antioxidant, and Neuroprotective Activities
No full textCOX-2 enzyme is implicated in Alzheimer's disease (AD) through amyloid beta (Aß) accumulation, tau aggregation, and neuroinflammation. However, clinical outcomes of COX-2 inhibitors in AD have been inconsistent. This study explores novel series of pyrazolidinones and pyrazolidinediones as selective COX-2 inhibitors. Among these, 4-hydrazonopyrazolidinediones exhibited potent COX-2 inhibition, reducing PGE2 release in a THP-1 cell model. Compounds 15 and 16 demonstrated multitargeting potential by inhibiting Aß and tau aggregation (PHF6 and R3) and showed significant neuroprotective effects against Aß and H 2 O 2 -induced toxicity in SH-SY5Y cells without cytotoxicity. Additionally, both compounds displayed high permeability in PAMPA and MDCK-MDR1 assays, indicating their potential to cross the blood-brain barrier and reach therapeutic targets. These findings highlight the potential of reviving COX-2 inhibitors as multitargeted therapeutic agents for AD, offering a promising strategy to address multiple pathological aspects of the disease, including neuroinflammation, amyloid aggregation, and tau pathology.</p
Knowledge-sharing Behaviour Through Leadership and Culture: The Moderating Role of Job Autonomy and Gender
No full textThis study explores the impact of participative leadership, digital leadership, and digital organisational culture on employees’ knowledge-sharing behaviour within the Malaysian tourism sector. Data was collected from 412 employees across various organisations, and the analysis employed PLS-SEM to validate the hypotheses. The findings indicate that participative leadership, digital leadership, and digital organisational culture have a significant influence on employees’ knowledge-sharing behaviour. Additionally, the research highlights that job autonomy acts as a significant moderator in the relationship between digital organisational culture and knowledge-sharing behaviour. However, gender was found not to moderate the effects of participative leadership, digital leadership, or digital organizational culture on knowledge-sharing behaviour. This study makes significant contributions to the strategic deployment of technology in today’s digital business environment and offers important theoretical and practical implications, along with suggestions for future research.</p
Nixtamalization of Maize to Reduce Mycotoxin Exposure: A Human Biomonitoring Intervention Study in Soweto, South Africa
No full textThis study investigated whether nixtamalization, a traditional alkaline cooking process, can reduce mycotoxin contamination in maize and human exposure in Sub-Saharan Africa. Forty healthy adults from Kliptown, Soweto (South Africa) consumed either control maize or moldy maize treated with nixtamalization.Results showed that nixtamalization eliminated or drastically reduced several key mycotoxins in maize, fumonisin B3 and deoxynivalenol (DON) became undetectable, while fumonisin B1, fumonisin B2, and zearalenone (ZEN) decreased by 95%, 95%, and 89%, respectively; aflatoxin B1 was completely removed.However, urinary biomarkers of mycotoxin exposure (FB1, ZEN, α-/β-zearalenol, DON, and tenuazonic acid) did not differ significantly between treatment and control groups (p > 0.05), suggesting similar overall exposure levels.Overall, the study concludes that nixtamalization effectively reduces mycotoxin contamination in maize, and human biomonitoring provides a valuable method for assessing the impact of food safety interventions.</p
Screening of synthetic cannabinoids in herbal samples through three-dimensional voltammetry and PARAFAC
No full textSynthetic cannabinoids (SCs) are a class of drugs of abuse that stimulate the same endogenous cannabinoid receptors as tetrahydrocannabinol, capable of causing serious harm to a user’s health. As with many designer drugs, new variants frequently appear on the market, commonly associated with herbal mixtures, which can be complex in composition and contain unexpected components. This work proposes using three-dimensional differential pulse voltammetry (3D DPV) combined with parallel factor analysis (PARAFAC) for the detection and classification of SC classes, with changes in pulse time or amplitude as the second instrumental way. This methodology offers a second-order advantage, creating more robust models to the presence of unknown interferents. The models were built by analysing acetonitrile-based herbal extracts of street samples (n = 48), and marshmallow blanks (n = 9). Street samples included varying mixtures of 5F-AKB48, AKB48, 5F-PB-22, BB-22, AB-CHMINACA, and AB-FUBINACA. While amplitude change-based 3D DPV resulted in inaccurate detection models, PARAFAC models obtained by varying pulse times effectively detected and classified the street samples based on two factors: one representing indazole-based SCs (100 % accuracy for street samples and blanks) and the other representing indole-3-carboxylic acid 8-quinolinyl ester-based SCs (98.3 % accuracy for street samples and blanks). Therefore, it can effectively screen the modelled SC classes using a methodology that can be adapted for portable use.</p