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Dependence of thermomechanical response on Cu content in a hardenable Al-Si-Mg alloy
Get PDFIn this study, we investigated the effect of Cu content on the thermomechanical response of a precipitation-hardenable Al-Si-Mg alloy produced by the casting and rolling processes. The Cu content ranged from 0.35 to 0.95 wt.%, while the alloy maintained fixed amounts of Si and Mg. The thermomechanical process included pre-aging (PA), stretching by 4% (S), and post-aging (T6). The results were based on the yield strength (YS) and the thermomechanical response was defined as YS_PAST6 – YS_T6. The findings indicated that at low and medium levels of Cu, the YS of the samples in PA and PAS conditions remained mostly constant at 206 and 281 MPa, respectively. However, it increased from 334 (low Cu) to 351 MPa (medium Cu) when the PAST6 process was completed. At a high level of Cu content, the YS_PA and YS_PAS enhanced to 221 and 298 MPa, respectively. Nevertheless, the YS after complete PAST6 was 349 MPa, slightly lower than that of the alloy containing medium Cu level. It was observed that the thermomechanical response of the alloy is at its maximum (50 MPa) when the amount of Cu is around the middle of the defined range.The authors acknowledge the financial support by EPSRC (UK) through the STEP Al grant (EP/S036296/1)
Multi-Cross Sampling and Frequency-Division Reconstruction for Image Compressed Sensing
Get PDFAAAI Technical Track on Computer Vision IVThe lecture presentation, slides, conference paper and transcript are available online at: https://underline.io/lecture/92149-multi-cross-sampling-and-frequency-division-reconstruction-for-image-compressed-sensing .Deep Compressed Sensing (DCS) has attracted considerable interest due to its superior quality and speed compared to traditional algorithms. However, current approaches employ simplistic convolutional downsampling to acquire measurements, making it difficult to retain high-level features of the original signal for better image reconstruction. Furthermore, these approaches often overlook the presence of both
high- and low-frequency information within the network, despite their critical role in achieving high-quality reconstruction. To address these challenges, we propose a novel Multi-Cross Sampling and Frequency Division Network (MCFDNet) for image CS. The Dynamic Multi-Cross Sampling (DMCS) module, a sampling network of MCFD-Net, incorporates
pyramid cross convolution and dual-branch sampling with multi-level pooling. Additionally, it introduces an attention mechanism between perception blocks to enhance adaptive learning effects. In the second deep reconstruction stage, we design a Frequency Division Reconstruction Module (FDRM). This module employs a discrete wavelet transform
to extract high- and low-frequency information from images. It then applies multi-scale convolution and selfsimilarity attention compensation separately to both types of information before merging the output reconstruction results. MCFD-Net integrates the DMCS and FDRM to construct an end-to-end learning network. Extensive CS experiments
conducted on multiple benchmark datasets demonstrate that our MCFD-Net outperforms state-of-the-art approaches, while also exhibiting superior noise robustness
Synergistic effect of hybrid reinforcement on magnesium-based composites for enriching mechanical and tribological characteristics
Get PDFSupplementary material is available online at: https://journals.sagepub.com/doi/10.1177/09544089231221683#supplementary-materials .The exceptional mechanical, microstructural, and tribological characteristics of friction stir processed (FSP) hybrid and mono nanocomposite materials resulted in growing research interest. In the presented work, the base matrix of magnesium-based AZ31B alloy was reinforced with fly ash (FA) and nano-titanium carbide (n-TiC) particulates using FSP and resulting in both hybrid and mono composite surfaces. The microstructures and homogeneous distribution of reinforcing particulates of the synthesized composites were investigated with optical microscopy (OM) and field emission scanning electron microscopy (FESEM). In addition, for the synthesized nanocomposites, mechanical and tribological characteristics were investigated including using tensile and compression strength, micro/nano-hardness, and wear characteristics. The OM and FESEM data indicate that owing to the significant impact of the FSP process, grain refinement and the homogenous dispersion of the FA and n-TiC nanoparticles for both mono and hybrid composites were achieved. Overall, the new nano-hybrid composites have better mechanical properties due to improved interfacial bonding and homogeneous dispersion of hybridized n-TiC/FA reinforcements. The results indicate that the AZ31B/FA/TiC hybrid nanocomposite has better mechanical and tribological characteristics than the base alloy and the mono composite materials. More specifically, the grain size was reduced nearly 20 times, microhardness was 1.72 times higher, ultimate tensile strength was 2.42 times higher, compressive strength was 2.57 times higher, and wear rate was, about 80% higher when contrasted to the base alloy. Lastly, it is expected that this composite can offer a remarkable solution for crafting high-performance automotive parts.The authors received no financial support for the research, authorship, and/or publication of this article
Extraction of raw materials could rise 60% by 2060 - so is degrowth the answer?
No full textThis article is republished from The Conversation under a Creative Commons license. Image rights: Parilov/Shutterstock. Read the original at https://theconversation.com/extraction-of-raw-materials-could-rise-60-by-2060-and-making-mining-greener-wont-stop-the-damage-222818 .The United Nations’ flagship Global Resources Outlook report is the portrait of a juggernaut. Due to be published later this month by the UN’s International Resource Panel, it highlights how global consumption of raw materials, having increased four-fold since 1970, is set to rise by a further 60% by 2060
Exogenous shocks and time-varying price persistence in the EU27
Get PDFJEL Classification: C22; E31This paper analyses monthly price persistence in the EU27 countries over the period 2010–2022 using a fractional integration framework, where the measure of persistence is the fractional differencing parameter d. In addition to full sample estimates, subsample and recursive ones are obtained to examine time variation. On the whole, the results provide clear evidence that both the exogenous shocks considered (namely, the COVID-19 pandemic and the Russia-Ukraine war) have generally increased price persistence in the EU27 (despite their heterogeneity), although the recursive estimates suggest that their impact might have peaked and might now be decreasing. Therefore, any policies adopted to counteract those shocks should be gradually phased out. The exceptions are the Southern European countries, where price persistence appears to have decreased, though in Italy the recursive analysis indicates that it is now rising sharply.The work was supported by the Ministerio de Ciencia e Innovación [PID2020-113691RB-I00]
Gendered Constructions of Luck at Work: The Case of Career Narratives of Female and Male Managers
Get PDFThere is a ubiquitous assumption that luck is a gender-neutral and equally distributed phenomenon. Drawing on 50 interviews with female and male managers, we examine their constructions of luck at work and demonstrate the gendered construction of luck in career narratives. Despite the dearth of attention to luck in the career literature, luck often features in the career narratives of professional workers. In line with the literature, we define the construct of luck as something outside the locus of control of individuals. Yet, we identify that luck is a gendered construct in career narratives. We demonstrate that while female managers define luck as receiving equality of opportunity in the process of their careers, male managers define luck as structures of support that offer them opportunities above and beyond their merit at work, which is a privilege that men appear to enjoy. The perception and interpretation of luck have far-reaching effects on addressing and comprehending gender disparities in career advancement, decision-making, negotiation and organisational leadership. Recognising the gender-specific impact of luck is vital in promoting gender equality and offering equitable chances for the career progression of women and non-privileged employees. It offers a persuasive option to challenge the dominant meritocratic assumptions on equality of chances, structures and the distribution of resources.No funding was received for conducting this study
Women's subsistence strategies predict fertility across cultures, but context matters
Get PDFData, Materials, and Software Availability. Anonymized CSV file data have been deposited in OSF (https://osf.io/8d9n2/?view_only=9e07c25 e06414f7a8d041e80e8539e5c) (49).Supporting Information is available online at: https://www.pnas.org/doi/suppl/10.1073/pnas.2318181121/suppl_file/pnas.2318181121.sapp.pdf .While it is commonly assumed that farmers have higher, and foragers lower, fertility compared to populations practicing other forms of subsistence, robust supportive evidence is lacking. We tested whether subsistence activities—incorporating market integration—are associated with fertility in 10,250 women from 27 small-scale societies and found considerable variation in fertility. This variation did not align with group-level subsistence typologies. Societies labeled as “farmers” did not have higher fertility than others, while “foragers” did not have lower fertility. However, at the individual level, we found strong evidence that fertility was positively associated with farming and moderate evidence of a negative relationship between foraging and fertility. Markers of market integration were strongly negatively correlated with fertility. Despite strong cross-cultural evidence, these relationships were not consistent in all populations, highlighting the importance of the socioecological context, which likely influences the diverse mechanisms driving the relationship between fertility and subsistence.A.E.P. received funding from the Medical Research Council MRC (grant no. MR/P014216/1). J.S. acknowledges Institute for Advanced Study in Toulouse funding from the French National Research Agency (ANR) under the Investments for the Future (Investissements d’Avenir) program, grant ANR-17-EURE-0010. This material is based upon work supported while S.M. served at the National Science Foundation (NSF)
IQGAP1 and NWASP promote human cancer cell dissemination and metastasis by regulating β1-integrin via FAK and MRTF/SRF
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* All data are available in the main text or the supplementary materials. Original western blot images are in the supplemental material.
Blot and imaging data reported in this paper will be shared by the lead contact upon request.
* This paper does not report original code.
* Any additional information required to reanalyze the data reported in this paper is available
from the lead contact, Anne Ridley ([email protected]). upon request.Supplemental information is available online at: https://www.cell.com/cell-reports/fulltext/S2211-1247(24)00317-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2211124724003176%3Fshowall%3Dtrue#supplementaryMaterial .Summary:
Attachment of circulating tumor cells to the endothelial cells (ECs) lining blood vessels is a critical step in cancer metastatic colonization, which leads to metastatic outgrowth. Breast and prostate cancers are common malignancies in women and men, respectively. Here, we observe that β1-integrin is required for human prostate and breast cancer cell adhesion to ECs under shear-stress conditions in vitro and to lung blood vessel ECs in vivo. We identify IQGAP1 and neural Wiskott-Aldrich syndrome protein (NWASP) as regulators of β1-integrin transcription and protein expression in prostate and breast cancer cells. IQGAP1 and NWASP depletion in cancer cells decreases adhesion to ECs in vitro and retention in the lung vasculature and metastatic lung nodule formation in vivo. Mechanistically, NWASP and IQGAP1 act downstream of Cdc42 to increase β1-integrin expression both via extracellular signal-regulated kinase (ERK)/focal adhesion kinase signaling at the protein level and by myocardin-related transcription factor/serum response factor (SRF) transcriptionally. Our results identify IQGAP1 and NWASP as potential therapeutic targets to reduce early metastatic dissemination.This work was funded by a Cancer Research UK grant (C6620/A15961) (A.J.R., C.C., R.G., and N.R.), the University of Bristol School of Cellular and Molecular Medicine (A.J.R. and C.C.), a Cancer Research UK Oxford Center DPhil Prize Studentship (BBRTJW00) (S.L.), the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement (no. 655817) MSCA-IF-2014 (S.T.M. and A.R.), a Cancer Research UK grant A1731 (R.M.), and the Biotechnology and Biological Sciences Research Council (grant no. BB/K009184/1) (I.A.R.)
Shape Sensing for Continuum Robotics Using Optoelectronic Sensors with Convex Reflectors
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The data presented in this study are available in this article.Three-dimensional shape sensing in soft and continuum robotics is a crucial aspect for stable actuation and control in fields such as minimally invasive surgery, engine repairs and search and rescue operations, as the estimation of complex curvatures while using continuum robotic tools is required to manipulate through fragile paths. This challenge has been addressed using a range of different sensing techniques, for example, Fibre Bragg grating (FBG) technology, inertial measurement unit (IMU) sensor networks, or stretch sensors. Previously, an optics-based method using optoelectronic sensors was explored, offering a simple and cost-effective solution for shape sensing in a flexible tendon-actuated manipulator in two orientations. This was based on proximity-modulated angle estimation and has been the basis for the shape sensing method addressed in this paper. The improved and miniaturised technique demonstrated in this paper is based on the use of a convex shaped reflector with optoelectronic sensors integrated into a tendon-actuated robotic manipulator. Upgraded sensing capability is achieved using optimisation of the convex reflector shape in terms of sensor range and resolution, and improved calibration is achieved through the integration of spherical bearings for friction-free motion. Shape estimation is achieved in two orientations upon calibration of sensors, with a maximum Root-Mean-Square Error (RMS) of 3.37°.Engineering and Physical Sciences Research Council, grant number (EP/T518116/1)
Heat-related changes in the velocity and kinetic energy of flowing blood influence the human heart's output during hyperthermia
Get PDFThis study was conducted at the Centre for Human Performance, Exercise and Rehabilitation, Brunel University London, between March 2017 and March 2018.Data availability statement:
The data that support the findings of this study are available from the corresponding author upon reasonable request.Supporting information is available online at: https://physoc.onlinelibrary.wiley.com/doi/10.1113/JP285760#support-information-section .Passive whole-body hyperthermia increases limb blood flow and cardiac output (˙Q), but the interplay between peripheral and central thermo-haemodynamic mechanisms remains unclear. Here we tested the hypothesis that local hyperthermia-induced alterations in peripheral blood flow and blood kinetic energy modulate flow to the heart and ˙Q. Body temperatures, regional (leg, arm, head) and systemic haemodynamics, and left ventricular (LV) volumes and functions were assessed in eight healthy males during: (1) 3 h control (normothermic condition); (2) 3 h of single-leg heating; (3) 3 h of two-leg heating; and (4) 2.5 h of whole-body heating. Leg, forearm, and extracranial blood flow increased in close association with local rises in temperature while brain perfusion remained unchanged. Increases in blood velocity with small to no changes in the conduit artery diameter underpinned the augmented limb and extracranial perfusion. In all heating conditions, ˙Q increased in association with proportional elevations in systemic vascular conductance, related to enhanced blood flow, blood velocity, vascular conductance and kinetic energy in the limbs and head (all R^2 ≥ 0.803; P < 0.001), but not in the brain. LV systolic (end-systolic elastance and twist) and diastolic functional profiles (untwisting rate), pulmonary ventilation and systemic aerobic metabolism were only altered in whole-body heating. These findings substantiate the idea that local hyperthermia-induced selective alterations in peripheral blood flow modulate the magnitude of flow to the heart and ˙Q
through changes in blood velocity and kinetic energy. Localised heat-activated events in the peripheral circulation therefore affect the human heart's output.Partially supported by grants from the Ministry of Education, Culture, Sports, Science and Technology of Japan (JSPS KAKENHI) grant numbers 19K20034 and 21K17582
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