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Nickel-based superalloys such as Hastelloy X (HX) are widely used in gas turbine engines for their exceptional oxidation resistance and high-temperature strength. The addition of ceramic reinforcement further enhances these superalloys’ mechanical performance and high-temperature properties. For this reason, this paper investigates the microstructure and mechanical property of laser powder bed fusion (LPBF) additively manufactured HX–1 wt% WC (tungsten carbide) composite specimens. The results demonstrate that the LPBF-fabricated composite was observed to have several pores and microcracks, whilst only pores were detected in the as-fabricated pure HX. Compared to the fabricated pure HX, the tensile yield strength of such HX composite parts was increased by 13% without undue sacrifices to ductility, suggesting that the very limited number of microcracks were not sufficient to degrade the mechanical performance. The significantly increased dislocations were considered to be the primary contributor for the mechanical performance enhancement in the LPBF-fabricated composite material. The findings offer a promising pathway to employ LPBF process to fabricate advanced microcrack-free composites with high-strength through a careful selection of ceramic reinforcement materials.

Selective laser melting (SLM) is a transformative manufacturing process due to its ability to manufacture complex metal parts directly from various bulk powders. With the capability of reducing powder consumption and decreasing fabrication times, lattice structures, which are used as infilling materials within hollow parts, offer an effective solution for decreasing the high costs that currently impede the wider application of SLM in various industries. The assessment of mechanical properties of SLM-built lattice structures, however, remain challenging due to their complicated geometries, while pursuing experimental studies proves to be time-consuming due to the requirement of numerous part fabrication and physical testing. To address these research challenges, this study proposes an analytical modelling approach conducting quasi-static analysis on Ti6Al4V (Ti64) lattice structures. In order to investigate the structures’ mechanical properties, dynamic balance equation of the structures under compression loads were first established, and the stress distribution of the structures was calculated explicitly using central difference method. The modelling approach was validated by conducting uniaxial compression tests on samples fabricated using SLM. The experiments showed that the equivalent elastic modulus ( E* ) and the ultimate stress ( UTS ) values of the Ti64 structures predicted by the analytical method were in good agreement with the experimental results. The paper also discusses the design principles of SLM-built lattice structures (mainly the selection of proper topologies and relative densities) and examines the necessity and flexibility of the proposed analytical approach compared with conventional theoretical methods and their experimental studies in the context of SLM process.

Industry 5.0 highlights human-centricity, sustainability, and resilience. This article presents a novel Trust by Design framework applicable to collaborative intelligence systems within Industry 5.0, addressing the need for collaborative systems to be reliable by design, incorporating ethical principles such as transparency, accountability, fairness, and privacy throughout the entire system lifecycle. The framework is grounded in select ethical philosophies applied to practical design requirements for human-AI collaboration, identifying key ethical challenges that threaten to damage trust and restrict the adoption of collaborative systems. The authors employ a qualitative, literature-driven method, conceptual modeling, and scenario-based case study analysis, synthesizing best practices and ethical policies from the EU AI Act, GDPR, and more. Trust by Design suggests a structured set of principles and implementation measures to embed ethics into every phase of the system’s lifecycle. The applicability and suitability of the framework are demonstrated through representative real-world application scenarios across industries. The results indicate that trust in collaborative intelligence systems is not static but dynamic, context-dependent, and controlled by transparency, fairness, and user experience. The framework includes instruments and methods to measure ethical performance, including trust metrics, override rates, fairness indicators, and incident tracking.

Purpose - The purpose of this paper is to examine the suitability of additive manufacturing technologies in the reconstruction of archaeological discoveries as illustrative models. The processes of reverse engineering and part fabrication are discussed in detail, with particular emphasis placed on the difficulties of managing scaling and material characteristics for the manufacturing process.Design methodology approach - Through a case-based approach, this paper examines the reconstruction of a fifteenth-century ship recovered from the River Usk in South Wales, UK. Using interviews and process data, the paper identifies challenges for both archaeologists and manufacturers in the application of additive manufacturing technologies for archaeological reconstruction applications.Findings - This paper illustrates both the suitability of additive manufacturing in archaeological restoration, but also the challenges which result from this approach. It demonstrates the practical considerations of scaling process and materials, whilst also highlighting the techniques to improve accuracy and mechanical properties of the model.Originality value - Whilst the technologies of additive manufacturing have previously been applied to model making, little scholarly research has considered the practical techniques of design elicitation and manufacturing for archaeological applications. Using an in-depth case study, this paper highlights the principal considerations for these applications, and provides guidance in the mitigation of manufacturing issues.

Constitutive laws that describe the mechanical responses of cardiac tissue under loading hold the key to accurately model the biomechanical behaviour of the heart. There have been ample choices of phenomenological constitutive laws derived from experiments, some of which are quite sophisticated and include effects of microscopic fibre structures of the myocardium. A typical example is the strain-invariant-based Holzapfel–Ogden 2009 model that is excellently fitted to simple shear tests. It has been widely used and regarded as the state-of-the-art constitutive law for myocardium. However, there has been no analysis to show if it has both adequate descriptive and predictive capabilities for other tissue tests of myocardium. Indeed, such an analysis is important for any constitutive laws for clinically useful computational simulations. In this work, we perform such an analysis using combinations of tissue tests, uniaxial tension, biaxial tension and simple shear from three different sets of myocardial tissue studies. Starting from the general 14-parameter myocardial constitutive law developed by Holzapfel and Ogden, denoted as the general HO model, we show that this model has good descriptive and predictive capabilities for all the experimental tests. However, to reliably determine all 14 parameters of the model from experiments remains a great challenge. Our aim is to reduce the constitutive law using Akaike information criterion, to maintain its mechanical integrity whilst achieving minimal computational cost. A competent constitutive law should have descriptive and predictive capabilities for different tissue tests. By competent, we mean the model has least terms but is still able to describe and predict experimental data. We also investigate the optimal combinations of tissue tests for a given constitutive model. For example, our results show that using one of the reduced HO models, one may need just one shear response (along normal-fibre direction) and one biaxial stretch (ratio of 1 mean fibre : 1 cross-fibre) to satisfactorily describe Sommer et al. human myocardial mechanical properties. Our study suggests that single-state tests (i.e. simple shear or stretching only) are insufficient to determine the myocardium responses. We also found it is important to consider transmural fibre rotations within each myocardial sample of tests during the fitting process. This is done by excluding un-stretched fibres using an “effective fibre ratio”, which depends on the sample size, shape, local myofibre architecture and loading conditions. We conclude that a competent myocardium material model can be obtained from the general HO model using AIC analysis and a suitable combination of tissue tests.

Background Cytomegalovirus retinitis (CMVR) is an opportunistic infection in HIV-infected people. Intraocular or intravenous ganciclovir was gold standard for treatment; however, oral valganciclovir replaced this in high-income countries. Low- and middle-income countries (LMIC) frequently use intraocular injection of ganciclovir (IOG) alone because of cost. Methods Retrospective review of all HIV-positive patients with CMVR from February 2013 to April 2017 at a Médecins Sans Frontièrs HIV clinic in Myanmar. Treatment was classified as local (IOG) or systemic (valganciclovir, or valganciclovir and IOG). The primary outcome was change in visual acuity (VA) post-treatment. Mortality was a secondary outcome. Results Fifty-three patients were included. Baseline VA was available for 103 (97%) patient eyes. Active CMVR was present in 72 (68%) eyes. Post-treatment, seven (13%) patients had improvement in VA, 30 (57%) had no change, and three (6%) deteriorated. Among patients receiving systemic therapy, four (12.5%) died, compared with five (24%) receiving local therapy ( p  = 0.19). Conclusions Our results from the first introduction of valganciclovir for CMVR in LMIC show encouraging effectiveness and safety in patients with advanced HIV. We urge HIV programmes to include valganciclovir as an essential medicine, and to include CMVR screening and treatment in the package of advanced HIV care.

Context Asian elephant numbers are declining across much of their range driven largely by serious threats from land use change resulting in habitat loss and fragmentation. Myanmar, holding critical range for the species, is undergoing major developments due to recent sociopolitical changes. To effectively manage and conserve the remaining populations of endangered elephants in the country, it is crucial to understand their ranging behavior. Objectives Our objectives were to (1) estimate the sizes of dry, wet, and annual ranges of wild elephants in Myanmar; and quantify the relationship between dry season (the period when human-elephant interactions are the most likely to occur) range size and configurations of agriculture and natural vegetation within the range, and (2) evaluate how percentage of agriculture within dry core range (50% AKDE range) of elephants relates to their daily distance traveled. Methods We used autocorrelated kernel density estimator (AKDE) based on a continuous-time movement modeling (ctmm) framework to estimate dry season (26 ranges from 22 different individuals), wet season (12 ranges from 10 different individuals), and annual range sizes (8 individuals), and reported the 95%, 50% AKDE, and 95% Minimum Convex Polygon (MCP) range sizes. We assessed how landscape characteristics influenced range size based on a broad array of 48 landscape metrics characterizing aspects of vegetation, water, and human features and their juxtaposition in the study areas. To identify the most relevant landscape metrics and simplify our candidate set of informative metrics, we relied on exploratory factor analysis and Spearman’s rank correlation coefficient. Based on this analysis we adopted a final set of metrics into our regression analysis. In a multiple regression framework, we developed candidate models to explain the variation in AKDE dry season range sizes based on the previously identified, salient metrics of landscape composition. Results Elephant dry season ranges were highly variable averaging 792.0 km 2 and 184.2 km 2 for the 95% and 50% AKDE home ranges, respectively. We found both the shape and spatial configuration of agriculture and natural vegetation patches within an individual elephant’s range play a significant role in determining the size of its range. We also found that elephants are moving more (larger energy expenditure) in ranges with higher percentages of agricultural area. Conclusion Our results provide baseline information on elephant spatial requirements and the factors affecting them in Myanmar. This information is important for advancing future land use planning that takes into account space-use requirements for elephants. Failing to do so may further endanger already declining elephant populations in Myanmar and across the species’ range.

Arsenic is carcinogenic and teratogenic. In addition, it is also a developmental neurotoxicant. Little is known however about the effect of arsenic exposure during brain development on social behavior. This study aimed to detect the effect of developmental arsenic exposure on social behavior and related gene expression in C3H adult male mice. Pregnant C3H mice were exposed to sodium arsenite (NaAsO2, 85 ppm in the drinking water) from gestational day (GD) 8 to 18. The F1 generation male pups from different mothers were taken and social behavior tasks were examined. Social behavioral-related gene expression in the prefrontal cortex was determined by the real-time RT-PCR method. The mice with developmental arsenic exposure showed poor sociability and poor social novelty preference. Glutamate receptor expression (NMDA and AMPA receptor subunits) showed no significant difference, but gene expressions of serotonin receptor 5B (5-HT 5B) and brain-derived neurotrophic factor (BDNF) were significantly decreased (p < 0.05) in the arsenic-exposed group compared to control group. The heme oxygenase-1 (HO-1) and cyclooxygenase-2 (COX-2) gene expressions were not significantly different. Our findings indicate that developmental arsenic exposure might affect social behavior by modulating serotonin receptors and reducing BDNF. Some oxidative stress markers and inflammatory markers were not affected.

Antimicrobials are used to support livestock health and productivity, but might pose a risk for the development of antimicrobial resistance; in particular, when multiple livestock species are raised together in production systems. On integrated chicken-fish farms, chickens are raised over fish ponds and poultry faeces is excreted into the ponds. We investigated antimicrobial usage and the antimicrobial susceptibility of Escherichia coli cultured from poultry faeces on 301 integrated farms in Ayeyarwady Delta of Myanmar. Antimicrobials were used by 92.4% of farmers for chickens, but they were not applied to fish. The most common antimicrobials used were Octamix (amoxicillin and colistin sulfate) on 28.4%, enrofloxacin on 21.0% and amoxicillin on 16% of farms. Overall, 83.1% (152/183) of the E. coli were resistant to at least one antimicrobial. The highest level of resistance was to amoxicillin (54.6%), tetracycline (39.9%), sulfamethoxazole/trimethoprim (35.5%) and enrofloxacin (34.4%). Multidrug resistance was identified in 42.4% of isolates. In general, we found similar levels of antimicrobial resistance in non-users of antimicrobials as in users of antimicrobials for more commonly applied antimicrobials. Overall, antimicrobial resistance was lower in chickens on these integrated farms in Myanmar, compared to poultry farms in other countries of South East and East Asia.