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The improvement of deformability in AA7075 alloy through cryogenic treatment and its correlation with microstructural evolution and FE modelling
Get PDFData availability: The data that support the findings of this study are available from the corresponding author upon reasonable request.Cryogenic treatment has high potential for improving the deformation behavior through the recrystallization at a low temperature. In this work, true stress–strain curves were obtained via compression tests to understand the deformation behavior of an AA7075 under cryogenic conditions. Results showed a significant improvement in the flow stress of AA7075, increasing from 260 to 560 MPa at the yield point. The strain hardening exponent (n) also increased from 0.25 to 0.35 after deformation at cryogenic temperatures. The presence of Al2CuMg phase influenced the deformation texture of the tested aluminum alloy, resulting in more elongated grains and fine sub-grains after deformation at cryogenic temperatures, due to the hindered recrystallization. Microstructure evolution after deformation at room and cryogenic temperatures was investigated using EBSD technique to characterize texture and recrystallized grains. The results indicated that the spacing of the high-angle grain boundaries (HAGBs) in the sample deformed at room temperature was slightly larger than in the cryogenically treated sample. The alloy deformed at the cryogenic temperature exhibited a higher strain hardening exponent (n = 0.35) compared to room temperature deformation (n = 0.25). Furthermore, finite element analysis supported the experimental findings, showing that the Plastic Equivalent Strain (PEEQ) of the model tested at cryogenic temperature was higher than at room temperature, attributed to grain refinement during low-temperature deformation. The calculated effective stress responses at cryogenic temperatures for the investigated flow stress aligned well with the experimental results. These new aspects and mechanisms of deformation of aluminum alloys at cryogenic temperatures can improve the formability of high-strength alloys in the future production of more complex and integrated lightweight components.The authors acknowledge the financial support provided by the Office of National Higher Education Science Research and Innovation Policy Council (NXPO), Thailand, through Program Management Unit for Human Resources & Institutional Development, Research and Innovation (PMU-B), Grant No. B05F63098
Genetic associations with psychosis and affective disturbance in Alzheimer's disease
Get PDFInga Margret Antonsdottir, Constantine Lyketsos, and Robert A. Sweet contributed equally to this study.Highlights:
· It has long been known that psychotic and affective symptoms are often comorbid in individuals diagnosed with Alzheimer's disease. Here we examined for the first time the genetic architecture underlying this clinical observation, determining that psychotic and affective phenotypes in Alzheimer's disease are genetically correlated.
· Nevertheless, psychotic and affective phenotypes in Alzheimer's disease diverged in their genetic correlations with psychiatric phenotypes assessed in individuals without Alzheimer's disease. Psychosis in Alzheimer's disease was negatively genetically correlated with bipolar disorder and positively with depressive symptoms, whereas the affective phenotypes in · Alzheimer's disease were positively correlated with anxiety disorder and more strongly correlated than psychosis with depressive symptoms.
Psychosis in Alzheimer's disease, and the joint psychotic and affective phenotype, had significant estimated heritability, whereas the affective in AD did not.
· Examination of the loci most strongly associated with the psychotic, affective, or joint phenotypes revealed overlapping and unique associations.INTRODUCTION:
Individuals with Alzheimer's disease (AD) commonly experience neuropsychiatric symptoms of psychosis (AD+P) and/or affective disturbance (depression, anxiety, and/or irritability, AD+A). This study's goal was to identify the genetic architecture of AD+P and AD+A, as well as their genetically correlated phenotypes.
METHODS:
Genome-wide association meta-analysis of 9988 AD participants from six source studies with participants characterized for AD+P AD+A, and a joint phenotype (AD+A+P).
RESULTS:
AD+P and AD+A were genetically correlated. However, AD+P and AD+A diverged in their genetic correlations with psychiatric phenotypes in individuals without AD. AD+P was negatively genetically correlated with bipolar disorder and positively with depressive symptoms. AD+A was positively correlated with anxiety disorder and more strongly correlated than AD+P with depressive symptoms. AD+P and AD+A+P had significant estimated heritability, whereas AD+A did not. Examination of the loci most strongly associated with the three phenotypes revealed overlapping and unique associations.
DISCUSSION:
AD+P, AD+A, and AD+A+P have both shared and divergent genetic associations pointing to the importance of incorporating genetic insights into future treatment development.NIH. Grant Numbers: AG027224, MH116046, AG071169
Human Evolutionary Demography: Closing Thoughts
No full textA complete understanding of demographic patterns and behaviours is not possible without including the role of evolutionary processes. Many challenges in the social sciences, and in demography in particular, can be more readily met if they include the rich collection of perspectives, models, tools, and theories that evolutionary sciences can provide. Perhaps unexpectedly, the benefits of this inclusion can be indirect, as many benefits of an evolutionary perspective may take the form of a new way of approaching an old problem that leads to insights independent of any goal related to isolating the role of natural selection or adaptation. In other cases, the role of adaptation may have been under-appreciated and can lead to a different understanding of the mechanisms involved. To help human evolutionary demography improve going forward, we offer two general recommendations. One is improving the integration of contemporary developments in evolutionary thought about the role of culture and environment, such as dual-inheritance theory, epigenetics, and the role of social learning and cultural transmission. Many of these developments reflect an increasingly sophisticated understanding of cultural processes in and understanding of core concepts like fitness and heritability. The role of culture may be a productive point of contact between the social sciences and evolutionary social sciences given shared interests in this area. Second is a call to re-invigorate evolutionary demography with some of the classical ideas that come from life history theory and population ecology, such as the use of energy and resource budgets to structure tradeoffs, a focus on the role of ecological factors like density and resources, and the use of formal mathematical models
Regulating of wear properties through microstructure engineering in novel cost-effective Fe30Ni25Cr25Mo10Al10 high-entropy alloy processed by cyclic closed-die forging
Get PDFThis study presents a novel cost-effective Fe30Ni25Cr25Mo10Al10 high-entropy alloy with a dual-phase microstructure that was processed using cyclic closed-die forging (CCDF) at room temperature for a maximum of six passes. The as-homogenized alloy exhibited [CrMoFe]-rich dendrites with dual-size morphology dispersed in an almost uniform face-centered cubic (FCC) matrix. It was found that as the number of CCDF passes increased, leading to a more homogenous nanograin, there was an accumulation of dislocations, fragmentation of [CrMoFe]-rich dendrites, and enhanced distribution within the matrix. These conditions were conducive to the creation of a nanostructured Fe30Ni25Cr25Mo10Al10 alloy with superior mechanical properties. Texture analysis indicated that the prominent texture components for the Fe30Ni25Cr25Mo10Al10 alloy after six passes were Rotated Cube {001}, S {123}, and Dillamore {4 4 11}. After the sixth CCDF pass, the Fe30Ni25Cr25Mo10Al10 alloy exhibited the highest microhardness (∼ 974 HV) and the lowest wear rate (∼ (0.8 ± 0.1) × 10–5 mm3.N−1.m−1). Additionally, it was proposed that the development of the Rotated Cube {001} texture component contributed positively to enhancing wear resistance in the cost-effective high-entropy alloys. Considering the obtained results, it is reasonable to propose that CCDF processing is significant potential for the advancement of cost-effective nanostructured high-entropy alloys for industrial applications.The study was supported by the Russian Science Foundation, project No.
24–29–00740, https://rscf.ru/en/project/24–29-00740/
A study on emission reduction and combustion efficiency, analyzing oxymethylene ether (OME1-5) with diesel fuel
No full textData availability: Data will be made available on request.This study investigates an optimized fuel blend comprising oxymethylene ethers (OMEn = 1–5 series) with diesel aimed at simultaneously reducing soot and NOx emissions while enhancing fuel efficiency. An optimal blend was identified through rigorous experimentation and computational fluid dynamics (CFD) modeling. The study employs the response surface method (RSM) for regression analysis and integrates machine learning techniques for predictive modeling to assess various fuel compositions and optimize the mixture for improved combustion dynamics. Experimental measurements were conducted in an optical constant volume combustion chamber (CVCC) to confirm the blend’s effectiveness in reducing both soot and NOx emissions. The investigation thoroughly analyzes spray combustion properties, including injection duration, Start of Combustion (SOC), End of Combustion (EOC), Lift-Off length of fuels, spray tip penetration, and their impact on combustion efficiency. Analysis of energy densities between the blends reveals that OMED exhibits a heating value superior to OME2-5 but inferior to diesel, striking a balance in energy output. Furthermore, OMED demonstrates superior energy density compared to OME1-3 and diesel, highlighting its potential for enhanced fuel efficiency. The optimized blend achieves a significant 78.2 % reduction in soot emissions and a 31.3 % reduction in NOx emissions compared to conventional diesel, underscoring its efficacy in mitigating harmful emissions without compromising combustion performance. This research contributes valuable insights into developing sustainable fuel solutions for diesel engines, paving the way for greener automotive technologies in the future.This research was financially supported by the College of Engineering Design and Physical Sciences at Brunel University London under grant number 11667100
Kidney Beam-A Cost-Effective Digital Intervention to Improve Mental Health
Get PDFData Availability Statement: Data collected during the study, including deidentified participant data will be made available on reasonable request, and following trial steering committee approval, by contacting corresponding author on [email protected]. The study protocol, statistical analysis plan, and other study forms can be obtained by visiting BMC Nephrology.19 The health economic analysis plan can be found in supplemental files.Supplementary Material is available online at: https://www.kireports.org/article/S2468-0249(24)01915-6/fulltext#app-1 .Introduction:
There is inequity in the provision of physical rehabilitation services for people living with chronic kidney disease (CKD). The Kidney BEAM trial evaluated the clinical value and cost effectiveness of a physical activity digital health intervention (DHI) in CKD.
Methods:
In a single-blind, 11 center, randomized controlled trial, 340 adult participants with CKD were randomly assigned to either the Kidney BEAM physical activity DHI or a waitlist control. This study assessed the difference in the Kidney Disease Quality of Life Short Form 1.3 Mental Component Summary (KDQoL-SF1.3 MCS) between intervention and control groups at 6-months, and cost-effectiveness of the intervention.
Results:
At 6-months, there was a significant difference in mean adjusted change in KDQoL MCS score between Kidney BEAM and waitlist control (intention-to-treat adjusted mean: 5.9 [95% confidence interval, CI: 4.4–7.5] arbitrary units [AU], P < 0.0001), and a 93% and 98% chance of the intervention being cost-effective at a willingness-to-pay threshold of £20,000 and £30,000 per quality-adjusted life year gained.
Conclusion:
The Kidney BEAM physical activity DHI is a clinically valuable and cost-effective means to improve mental health-related quality of life (HRQoL) in people with CKD (trial registration no. NCT04872933).This study was funded by a grant from Kidney Research UK: SP/BEAM/2020 HY, JB, RB, NB, MGB, TW are supported by the National Institute for Health Research Leicester Biomedical Research Centre. HW is funded by the National Institute for Health Research (NIHR) Applied Research Collaboration East Midlands (ARC EM)
Investigation into rockslides by the adaptive rock discrete fracture analysis (RDFA) method
Get PDFMeeting abstract from the EGU General Assembly 2024, Session NH3.5.The rock discrete fracture analysis (RDFA) method was proposed as a combination of the rock failure process analysis method and the discrete element method. Leveraging the statistical strength theory and contact mechanics, it can effectively capture the intricate continuum-discontinuum behaviors inherent in rock mechanics, encompassing fracture and fragmentation phenomena. Enabled by a sophisticated nodal updating scheme, RDFA can dynamically adjust nodes at critical crack tips in accordance with strength criteria, facilitating accurate modeling of zero-thickness crack initiation and propagation. Noteworthy is its capacity to accommodate the inherent heterogeneity of rock masses, enabling holistic consideration of localized damage and fine crack development. Rigorously validated through the Brazilian disc and uniaxial compression tests, RDFA consistently aligns with the analytical solutions and experimental data. After that, it was applied to analyze the rockslide characteristics at the Anshan Road station in the Qingdao metro, China, and illuminated crucial insights. The results show that in the presence of 60° oriented joints with 5m spacing, the high stress concentration primarily emerged at the slope toe, leading to the localized tensile damage and the formation of a sliding surface. Subsequent rock sliding induced compression and collision among blocks, precipitating continuous failure within the sliding body. Additionally, the presence of intermittent joints notably contributed to progressive rockslide, particularly triggering the localized failures in the lower part of the slope
A survey of experts to identify methods to detect problematic studies: Stage 1 of the INSPECT-SR Project
No full textData availability:
The study dataset is available at https://osf.io/6pmx5/.Supplementary data are available online at: https://www.sciencedirect.com/science/article/pii/S0895435624002683#appsec1 .A preprint version of this article is available on medRxiv at: https://www.medrxiv.org/content/10.1101/2024.03.18.24304479v2 . It has not been certified by peer review.Background and Objective:
Randomized controlled trials (RCTs) inform health-care decisions. Unfortunately, some published RCTs contain false data, and some appear to have been entirely fabricated. Systematic reviews are performed to identify and synthesize all RCTs which have been conducted on a given topic. This means that any of these ‘problematic studies’ are likely to be included, but there are no agreed methods for identifying them. The INveStigating ProblEmatic Clinical Trials in Systematic Reviews (INSPECT-SR) project is developing a tool to identify problematic RCTs in systematic reviews of health care-related interventions. The tool will guide the user through a series of ‘checks’ to determine a study's authenticity. The first objective in the development process is to assemble a comprehensive list of checks to consider for inclusion.
Methods:
We assembled an initial list of checks for assessing the authenticity of research studies, with no restriction to RCTs, and categorized these into five domains: Inspecting results in the paper; Inspecting the research team; Inspecting conduct, governance, and transparency; Inspecting text and publication details; Inspecting the individual participant data. We implemented this list as an online survey, and invited people with expertise and experience of assessing potentially problematic studies to participate through professional networks and online forums. Participants were invited to provide feedback on the checks on the list, and were asked to describe any additional checks they knew of, which were not featured in the list.
Results:
Extensive feedback on an initial list of 102 checks was provided by 71 participants based in 16 countries across five continents. Fourteen new checks were proposed across the five domains, and suggestions were made to reword checks on the initial list. An updated list of checks was constructed, comprising 116 checks. Many participants expressed a lack of familiarity with statistical checks, and emphasized the importance of feasibility of the tool.
Conclusion:
A comprehensive list of trustworthiness checks has been produced. The checks will be evaluated to determine which should be included in the INSPECT-SR tool.This study/project is funded by the NIHR Research for Patient Benefit programme (NIHR203568). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care
Breaking the Boundaries in the Digital Age: Open Banking and Tax Evasion
Get PDFData Availability Statement: The data presented in this study are available on request from the corresponding author.In this paper, we examine the relationship between open banking and tax evasion. As the open banking literature is still evolving, we try to systematically analyze the literature on conventional banking and tax evasion and then extend the discussion in the context of open banking. The popularity of open baking recently raises a question about its relationship with tax evasion. Digital banking and digital taxation contributed positively to mitigating tax evasion in the context of conventional banking. However, in open banking, the customers can decide to what extent they will share any transaction-related data with their bank, while they can also choose to complete direct transactions with third parties. This creates a new challenge in relation to the mitigation of tax evasion, which is the focus of this paper. Due to lack of granular empirical data, we conduct a systematic literature review and a bibliometric analysis to track the development of the relevant academic debates and identify the arguments that have been presented in relation to this topic. This approach is recognized as well suited for emerging topics in finance research, particularly when data are scarce, as evidenced by studies on COVID-19 and biodiversity. We find that the gaps of the current regulatory framework, at both the national and supranational level, have created challenges and uncertainties at multiple levels. Nonetheless, the findings of the study suggest future research directions and offer valuable guidelines for regulators in utilizing open banking.This research received no external funding
Nanobubbles in graphene-based nanofluids: Unraveling the mechanisms behind nucleation, behaviour and thermophysical properties using a molecular approach
Get PDFData availability: The data of this paper can be accessed from the Brunel University London data archive, figshare at https://brunel.figshare.com .Supplementary data are available online at: https://www.sciencedirect.com/science/article/pii/S0016236124016661?via%3Dihub#s0045 .Significant endeavors have been undertaken to substitute conventional thermal fluids with those possessing enhanced thermophysical properties, wherein nanoscale phenomena, particularly the integration of nanoparticles like graphene, play a crucial role. Graphene's exceptional properties and interactions with surrounding molecules make it an ideal candidate for nanoparticle integration, particularly in renewable energy applications such as solar energy. The introduction of dissolved gases, especially in industrial processes like electrochemical reactions, further influences fluid behavior and thermophysical properties, potentially leading to the formation of nanobubbles, with this alteration becoming even more pronounced. This study employs molecular dynamics simulations to investigate nanobubble formation, behavior, and their impact on the inherent properties of graphene-water and graphene-methanol nanofluids, featuring a 9.5 nm × 9.5 nm graphene sheet immersed in 98,000 water molecules and 48,000 methanol molecules, respectively. The findings reveal distinct behaviors depending on the host liquid, with two-atom gases forming graphene-nanobubbles in water-based nanofluid, while nitrogen and hydrogen predominantly form bulk nanobubbles in methanol. Moreover, the presence of formed nanobubbles and dispersed graphene increases water viscosity but decreases it in two-atom gas/graphene-methanol nanofluids. The lowest viscosity is recorded for the graphene/methanol sample with hydrogen nanobubbles at 0.00053 Pa.s, while the highest viscosity is observed for the oxygen methanol sample without nanobubbles at 0.00068 Pa.s. Conversely, the specific heat capacity of water-based nanofluids decreases due to nanobubbles and dispersed graphene, particularly pronounced in oxygen/graphene-nanofluid. While in methanol-based nanofluids, the specific heat capacity increases, notably in oxygen-graphene/methanol nanofluids.This work was supported by a UKRI Future Leaders Fellowship (MR/T042915/1) and EPSRC DTP (EP/T518116/1-2688449). MD simulations were run on ARCHER2 and MMM Hub Young, the UK's National Supercomputing Service
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