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Automated robotic system for dual ultrasonic and eddy current array integration and data fusion in wire arc additive manufacturing material inspection
No full textWire Arc Additive Manufacturing (WAAM) is a direct energy deposition method that enables the fabrication of large, complex metal components with minimal material waste, making it a key technology within Industry 4.0. However, WAAM is prone to weld-like defects, such as lack of fusion, keyholes, and porosities, which compromise structural integrity and require a reliable Non-Destructive Evaluation (NDE). Conventional post-process inspection methods, including Ultrasonic Testing (UT) and X-ray imaging, can detect such defects but often lead to costly rework once fabrication is complete. This work presents a dual-sensor robotic inspection system enabling simultaneous phased array UT and Eddy Current Testing (ECT) during WAAM deposition for early defect detection and efficient process monitoring. The system integrates an industrial manipulator with closed-loop force-torque control for repeatable layer-wise scanning without tool changes or process interruption. The system was evaluated using two Ti-6Al-4V reference blocks that replicated WAAM geometries and contained artificial defects. A depth-weighted C-scan data fusion approach, supported by targeted ECT denoising, improved contrast-to-noise ratio by 4.44 dB and 9.02 dB for the two samples, respectively. The approach was further validated on a titanium WAAM sample containing embedded tungsten inclusions, demonstrating the robustness of the methodology. A receiver operating characteristic analysis further confirmed the improved defect discrimination of the fused data, consistently resulting in higher area-under-curve values than either UT or ECT alone across all evaluated samples
A chemical probe for prostate-specific membrane antigen for real-time Raman imaging of prostate cancer cells
No full textIntraoperative detection of localised prostate cancer is challenging with direct consequences for long-term, suc-cessful treatment of the disease. Optical imaging techniques have been incorporated in the surgical environment, often using theranostic agents to rapidly and accurately determine the tumour margin. Here, we develop the first small molecule probe that specifically targets prostate-specific membrane antigen (PSMA) for detection using stimulated Raman scattering (SRS) microscopy. The incorporation of an alkyne tag into the glutamate-ureido-lysine moiety, which has high affinity for PSMA, yielded the probe, PSMA-BADY. The selectivity and specificity of the probe was established in prostate cancer cell models with known PSMA expression profiles, indicating the potential of PSMA-BADY for localising PSMA in multicellular environ-ments using SRS microscopy
Distribution of capsule and O types in Klebsiella pneumoniae causing neonatal sepsis in Africa and South Asia : A meta-analysis of genome-predicted serotype prevalence to inform potential vaccine coverage
Get PDFBackground: Klebsiella pneumoniae causes ~20% of sepsis in neonates, with ~40% crude mortality. A vaccine administered to pregnant women, protecting against ≥70% of K. pneumoniae infections, could avert ~400,000 cases and ~80,000 deaths annually, mostly in Africa and South Asia. Vaccine formulations targeting the capsular polysaccharide (K) or lipopolysaccharide (O) antigens are in development. Global K. pneumoniae populations display extensive K and O diversity, necessitating a polyvalent vaccine targeted to the serotypes associated with neonatal disease in relevant geographical regions. We investigated the prevalence of K and O types associated with neonatal sepsis in Africa and South Asia to inform maternal vaccine design. Methods and findings: We analysed 1,930 K. pneumoniae neonate blood isolates from 13 surveillance studies across 35 sites in 13 countries. We used pathogen whole-genome sequencing to predict K and O serotypes and adjust for local transmission clusters, and Bayesian hierarchical meta-analysis to estimate K and O prevalence overall and per region, treating site as a random effect. Eighty-seven K loci were identified. KL2, KL102, KL25, KL15, and KL62 accounted for 49% of isolates. We estimate that 20 K loci, combining the eight most prevalent per region, could cover 72.9% of all infections (95% credible interval: [69.4%, 76.5%]) and ≥70% in each of Eastern, Western, and Southern Africa and South Asia. Preliminary findings from three sites suggested sufficient temporal stability of K loci to maintain 20-valent K vaccine coverage over 5–10 years, but more longitudinal data are needed to support this prediction. O types were far less diverse (n = 14 types). We estimate the top-5 (O1⍺β,2⍺, O1⍺β,2β, O2⍺, O2β, and O4) would cover 86.2% [82.6, 89.9%] of total infections (76%–92% per region), while the top-10 would cover ~99% of infections in all four regions. The main limitations of our study are the reliance on genome sequences to predict K and O serotypes (as serological typing is not available) and a lack of longitudinal data to explore stability of antigen prevalence over time. Conclusions: Neonatal sepsis is associated with diverse K and O types, with substantial geographic and temporal variation even after adjusting for localised transmission clusters. Despite this, a single 20-valent K vaccine could theoretically cover ≥70% of infections in all target regions. Locally-targeted vaccines could achieve higher coverage with lower valency, but are less feasible. In principle, very high coverage could be achieved with lower valency O-based vaccines, however, the protective efficacy against disease of antibodies targeting the O antigen remains uncertain. Further research is needed on cross-reactivity, antigen exposure, and stability of antigens over time, to better inform vaccine development
A hybrid physics–Bayesian framework for fatigue design curves under cryogenic conditions with consideration of load ratio and residual stress
Get PDFFatigue performance is a critical design consideration for cryogenic structures used in the storage and transport of alternative fuels such as liquefied natural gas (LNG), ammonia, and captured CO2. However, fatigue crack growth rate (FCGR) testing at cryogenic temperatures is expensive and prone to uncertainty due to complex experimental conditions. This study proposes a physics-informed Bayesian framework to improve the prediction and design of FCGR behaviour without extensive cryogenic testing. Four probabilistic models are developed: two Gaussian process (GP) regressions, a physics-informed Bayesian neural network (PIBNN), and a hybrid physics–GP fusion model. The framework explicitly incorporates temperature-dependent material properties, residual stress, load ratio, and crack closure mechanisms while utilising Bayesian inference to quantify epistemic and aleatory uncertainties. The physics-informed components constrain the model to physically admissible trends, improving extrapolation beyond the training data. Based on these models, Bayesian design curves are constructed to replace the traditional “mean + 2SD” rule, achieving a balanced level of conservatism with quantified confidence intervals. The proposed approach demonstrates reliable prediction of fatigue behaviour under untested cryogenic conditions, offering a data-efficient and mechanistically consistent tool for the design and integrity assessment of cryogenic structures
Camptothecin-bearing PEGylated polypropylenimine dendriplexes for prostate cancer gene therapy : impact of microfluidic processing on physicochemical properties and transfection
Get PDFBackground/Objectives: Prostate cancer is the most commonly diagnosed cancer in men and a leading cause of cancer-related mortality, highlighting the need for delivery systems capable of efficiently transporting both chemotherapeutic drugs and therapeutic genes to tumor cells. Generation-3 diaminobutyric polypropylenimine (DAB) dendrimers display low toxicity, high drug loading capacity and efficient gene delivery, and can be engineered as camptothecin-bearing PEGylated carriers complexed with plasmid DNA. The aim of this study was to compare microfluidic processing with conventional hand mixing for the preparation of camptothecin-bearing PEGylated DAB dendriplexes and to evaluate the impact of formulation methods and microfluidic parameters on their physicochemical properties, cellular uptake and gene expression in prostate cancer cells. Methods: Camptothecin-bearing PEGylated DAB dendrimers were synthesized and complexed with plasmid DNA to form dendriplexes. Formulations were prepared either by microfluidics, using different total flow rates and aqueous: organic flow rate ratios, or by conventional hand mixing. The resulting dendriplexes were characterized for DNA condensation, particle size, polydispersity index and zeta potential. Morphology was assessed by transmission electron microscopy. Cellular uptake of fluorescein-labelled DNA and β-galactosidase reporter gene expression were evaluated in PC3-Luc and DU145 prostate cancer cells. Results: Both microfluidic and hand-mixed methods produced stable, nanosized, positively charged dendriplexes with efficient and sustained DNA condensation (more than 99% over 24 h). Microfluidic processing, particularly at an aqueous: organic flow rate ratio of 3:1, yielded dendriplexes with hydrodynamic diameters and zeta potentials comparable to or slightly improved over hand-mixed formulations. These microfluidic conditions significantly enhanced cellular uptake in both PC3-Luc and DU145 cells. In PC3-Luc cells, this translated into β-galactosidase expression levels comparable to hand-mixed dendriplexes and higher than naked DNA, whereas in DU145 cells, transfection efficiencies remained modest for all formulations despite increased uptake. Conclusions: Microfluidic processing enables the reproducible and scalable preparation of camptothecin-bearing PEGylated DAB dendriplexes with tunable physicochemical properties. Under selected conditions, in vitro cellular uptake and gene expression were comparable to conventional hand mixing, supporting microfluidics as a robust alternative platform for the manufacture of dendrimer-based systems for combined chemo–gene delivery in prostate cancer
Emotion-focused family therapy with families in Iran : effects on parental fear, self-blame and self-efficacy
Get PDFThis study, the first of its kind in Iran, evaluated the effectiveness of a two-day Emotion-Focused Family Therapy (EFFT) group workshop among Iranian mothers of adolescents aged 12–17 years, aimed at reducing fear and self-blame and increasing self-efficacy. During the pandemic, we recruited mothers struggling with their adolescents’ behavior (e.g. aggression, withdrawal, or refusal to talk). Participants matched for age and presenting issue were randomly assigned to experimental (18) or no-treatment control (18) condition. The experimental condition involved an intensive two-day EFFT training workshop (delivered either in person, n = 11, or online, n = 7) to help mothers more effectively manage their child’s challenging behaviors. All mothers (both experimental and control) completed two self- report measures, the Caregiver Traps Scale (CTS) and the Parental Self-Agency Measure (PSAM), pre- and post-intervention. Results included significant reductions in maternal fear and self-blame on the CTS in the experimental group (d = .77) but little or no pre-post change in the control group (−.02). Reported maternal self-efficacy on the PSAM improved somewhat (but not significantly) in the experimental group (.29); there was no change in the control group (−.05). Post hoc analyses indicated significant pre-post improvement for in-person (mean d = .86) but not online delivery (.16)
The role of Au–Cl adlayers in the Turkevich synthesis of gold nanoparticles
Get PDFReal-time surface-enhanced Raman spectroscopy reveals that Au–Cl adlayers modulate the surface chemistry of gold nanoparticles during Turkevich synthesis. The formation, evolution, and collapse of this adlayer account for the characteristic optical, electrochemical, and size changes observed during growth and termination, offering a unified chemical picture of gold nanoparticle synthesis
Arbuscular mycorrhizal fungi effect on the hydrological regime in vegetated soil
No full textArbuscular mycorrhizal fungi (AMF) are increasingly used as biofertilizers in agriculture and being implemented in geotechnical engineering to establish vegetation on slopes. It is therefore crucial to understand the geotechnical consequences of AMF inoculation on water removal and retention and, hence, on stability of embankments and cut slopes. A first series of laboratory experiments involved planting Medicago sativa or Lolium perenne in mini-lysimeters, either inoculated with Rhizophagus irregularis or Funneliformis mosseae, or left uninoculated, and the monitoring of transpiration rates. A second series only involved M. sativa with monitoring of transpiration rates plus pore-water pressure and soil water content. AMF inoculation in M. sativa in the first experiment increased potential transpiration by over 55% due to increased shoot biomass but produced no effect in the second experiment despite similar AMF colonization. This was attributed to nutrient scarcity in the first experiment that possibly promoted fungal growth to scavenge nutrients in soil pores not accessible to roots. AMF inoculation did not significantly affect L. perenne transpiration possibly because AMF did not offer competitive advantages compared to the fine fibrous roots. No differences were observed in water-limited transpiration, consistent with no changes in water retention behaviour observed at low degrees of saturation
Alkali-metal heavyweights : up and coming contenders in homogeneous catalysis?
Get PDFAlkali-metal compounds, particularly organolithium and lithium amide reagents, are indispensable organometallic reagents in synthesis, finding widespread applications in cornerstone stoichiometric organic processes. Recent advances in the development of heavier alkali-metal analogues have revealed their emerging potential not only to participate in stoichiometric processes but also to catalyze transformations traditionally dominated by precious transition metals. This perspective provides an overview of a selection of these applications focusing on hydrogen isotope exchange, alkene isomerization, C–C bond formation, hydrophosphination, and hydrogenation. Special focus is placed on current mechanistic understanding and alkali-metal effects, aiming to draw out key challenges and opportunities that may guide the future development of alkali-metal-mediated catalysis
Developing National Health Service pharmacists as researchers : learning from the Scottish Pharmacist Clinical Academic Fellowship Programme
Get PDFIn the United Kingdom (UK), the vision is to further develop the pharmacy workforce through career development pathways aligning to the Royal Pharmaceutical Society’s post-registration foundation, advanced, and consultant practice curricula, which align with the four pillars of advanced practice recognized across multiple healthcare professionals—clinical practice, leadership and management, education, and research. However, it has been recognized that research capacity, competency, and confidence within the pharmacy profession require development. It has been noted that it is this ‘pillar’ that most frequently impedes successful credentialing at both ‘Core advanced’ and ‘Consultant levels’. A report presenting the findings of a UK-wide call for evidence on clinical academic careers in pharmacy outlines recommendations to embed a research culture in pharmacy careers, develop a clinical academic pathway for pharmacy, and provide a pipeline of pharmacy research leaders. The establishment of such pathways would provide opportunities for building capacity within the profession. The Scottish Pharmacist Clinical Academic Fellowship (SPCAF) programme was created to develop a network of Clinical Academic Pharmacist posts; a collaborative initiative between National Health Service Education for Scotland and the two Pharmacy Higher Education Institutions in Scotland is aimed at developing pharmacists as researchers to advance pharmaceutical care within the National Health Service in Scotland. This commentary presents a summary of an archival review completed as part of a wider research programme that adopted a case study approach with the purpose of evaluating the SPCAF programme cohort 1 (2021–23). The scope is to support others looking to develop similar practice-based research programmes aiming to build research capacity, competence, and confidence in the pharmacy workforce
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