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The high pressure die casting (HPDC) is a technique that allows us to produce parts for various sectors of industry. It has a great application in such sectors as automotive, energy, medicine, as the HPDC allows us to produce parts very fast and very cheaply. The HPDC casting quality depends on many parameters. The parameters among others, are cast alloy alloy metallurgy, filling system design, casting technology elements geometry and orientation, as well as, machine operation settings. In the article, different plunger motion schemes of the HPDC machine were taken into account. Analyses lead to learning about plunger motion influence on the casting porosity and solidification process run. Numerical experiments were run with the use of MAGMASoft® simulation software. Experiments were performed for industrial casting of water pump for automotive. Main parameter taken into account was maximal velocity of the plunger in the second phase. The analysis covered porosity distribution, feeding time through the gate, temperature field during whole process, solidification time. Cooling curves of the casting in chosen points were also analysed. Obtained results allow us to formulate conclusions that connect plunger motion scheme, gate solidification time and the casting wall thickness on the solidification rate and porosity of the casting. [ABSTRACT FROM AUTHOR]

Corrosion of aluminum alloys is a significant concern for shipbuilders to ensure the longevity of ocean vessels and equipment. Hence, the study aims to evaluate the corrosion performance of Al-Si as automotive alloys with varying concentrations of Si in deep seawater using electrochemical impedance spectroscopy and potentiodynamic polarization techniques. The surface condition prior to corrosion, as well as after corrosion, is analyzed using optical and scanning electron microscopy. The entire test is performed at an ambient condition. The results demonstrate that the corrosion resistance improves in alloys with increasing amounts of Si near the eutectic level, after which the corrosion protection deteriorates. Higher Si concentrations show higher values for polarization resistance and open circuit potential. In contrast, corrosion current and corrosion rate values decrease with increasing Si concentration up to eutectic composition. Si assists the formation of SiO2 and MgO films through Mg2Si intermetallics along with the Al2O3 on the surfaces, which aids in corrosion resistance. Optical and scanning electron micrographs reveal the presence of films on the surfaces after corrosion, which exhibit pits and pinholes on the surfaces of the alloys with lower Si concentrations. Hypereutectic alloy is affected by corrosion of its pinhole-like defects. The corresponding EDS analysis also confirms the protective layer of different oxides on the surfaces. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) has been performed on 2024 aluminum alloy sheets. The process was carried out using two different cooling rate i.e., Air Cooling (FSP-AC) and cooling using the liquid nitrogen (FSP-NC). In the current research, the effect of different cooling rates on microstructures and relating precipitates has been investigated. The results have been shown that the average grain size in the stirred zone (SZ) has been decreased significantly in the FSP-NC (1.75 µm) condition, with respect to the FSP-AC (3.3 µm). The misorientation angle of grain boundaries created the special structure. The grain boundaries were facet in FSP-AC and FSP-NC and the rough boundaries was observed in FSP-AC specimen. TEM and EBSD analysis have been indicated the dissolution of ?-Al2Cu precipitates in the SZ in the FSP-NC specimen, while FSP-AC caused formation of supersaturated copper solid solution with ?-Al2Cu precipitates in the grain boundaries. Furthermore, in the both FSprocessed specimens (FSP-AC and FSP-NC) fine and dispersed Al20Cu2Mn3 precipitates have been observed. [ABSTRACT FROM AUTHOR]

New Findings: What is the central question of this study?Is the attenuation of the respiratory muscle metaboreflex preserved after detraining?What is the main finding and its importance?Inspiratory muscle training increased respiratory muscle strength and attenuated the respiratory muscle metaboreflex as evident by lower heart rate and blood pressure. After 5 weeks of no inspiratory muscle training (detraining), respiratory muscle strength was still elevated and the metaboreflex was still attenuated. The benefits of inspiratory muscle training persist after cessation of training, and attenuation of the respiratory metaboreflex follows changes in respiratory muscle strength. Respiratory muscle training (RMT) improves respiratory muscle (RM) strength and attenuates the RM metaboreflex. However, the time course of muscle function loss after the absence of training or 'detraining' is less known and some evidence suggest the respiratory muscles atrophy faster than other muscles. We sought to determine the RM metaboreflex in response to 5 weeks of RMT and 5 weeks of detraining. An experimental group (2F, 6M; 26 ± 4years) completed 5 weeks of RMT and tibialis anterior (TA) training (each 5 days/week at 50% of maximal inspiratory pressure (MIP) and 50% maximal isometric force, respectively) followed by 5 weeks of no training (detraining) while a control group (1F, 7M; 24 ± 1years) underwent no intervention. Prior to training (PRE), post‐training (POST) and post‐detraining (DETR), all participants underwent a loaded breathing task (LBT) to failure (60% MIP) while heart rate and mean arterial blood pressure (MAP) were measured. Five weeks of training increased RM (18 ± 9%, P < 0.001) and TA (+34 ± 19%, P < 0.001) strength and both remained elevated after 5 weeks of detraining (MIP‐POST vs. MIP‐DETR: 154 ± 31 vs. 153 ± 28 cmH2O, respectively, P = 0.853; TA‐POST vs. TA‐DETR: 86 ± 19 vs. 85 ± 16 N, respectively, P = 0.982). However, the rise in MAP during LBT was attenuated POST (−11 ± 17%, P = 0.003) and DETR (−9 ± 9%, P = 0.007) during the iso‐time LBT. The control group had no change in MIP (P = 0.33), TA strength (P = 0.385), or iso‐time MAP (P = 0.867) during LBT across all time points. In conclusion, RM and TA have similar temporal strength gains and the attenuation of the respiratory muscle metaboreflex remains after 5 weeks of detraining. [ABSTRACT FROM AUTHOR]

The direct modulation of T cell responses is an emerging therapeutic strategy with the potential to modulate undesired immune responses including, autoimmune disease, and allogeneic cells transplantation. We have previously demonstrated that poly(lactide‐co‐glycolide) particles were able to modulate T cell responses indirectly through antigen‐presenting cells (APCs). In this report, we investigated the design of nanoparticles that can directly interact and modulate T cells by coating the membranes from APCs onto nanoparticles to form membrane‐coated nanoparticles (MCNPs). Proteins within the membranes of the APCs, such as Major Histocompatibility Complex class II and co‐stimulatory factors, were effectively transferred to the MCNP. Using alloreactive T cell models, MCNP derived from allogeneic dendritic cells were able to stimulate proliferation, which was not observed with membranes from syngeneic dendritic cells and influenced cytokine secretion. Furthermore, we investigated the engineering of the membranes either on the dendritic cells or postfabrication of MCNP. Engineered membranes could be to promote antigen‐specific responses, to differentially activate T cells, or to directly induce apoptosis. Collectively, MCNPs represent a tunable platform that can directly interact with and modulate T cell responses. [ABSTRACT FROM AUTHOR]

Warm deep drawing of polypropylene, a semi‐crystalline thermoplastic polymer, is studied using finite element analysis. In this process, a circular polypropylene blank is preheated to a temperature much below its melting temperature and deep drawn into the shape of a flat‐bottom cylindrical cup using a punch‐die combination, both initially at 25°C. The material model used for the analysis considers the effects of varying temperature and strain rate during the deep drawing process on the depth of draw. The effects of blank holder force, initial blank temperature, blank diameter, and die and punch corner radii on the depth of draw are determined. Thickness, temperature, and strain variations in the drawn cups, punch forces, and failure modes are also determined. [ABSTRACT FROM AUTHOR]

Introduction: Rural communities contribute to national wellbeing, identities, economies, and social fabrics yet experience increased risk of mortality, morbidity, and disability, coupled with lower levels of income, formal education, and employment than urban citizens. Despite higher need, occupational therapy services are maldistributed to urban locations. Publications about non‐urban services discuss predominantly outreach‐based, individualist, rehabilitation for specified diagnoses/age groups. However, given this population level inequity, it is unclear why individualist focussed services are more commonly discussed. Understanding intentions expressed in publications about non‐urban service design may identify assumptions/limitations to current approaches and contribute to improved future services. Methods: Each of 117 publications identified in a scoping review was read by two reviewers to independently identify themes. Provisional themes were discussed and modified in an iterative process to develop final themes/subthemes. The first author reinterrogated the publications and coded data to identify relevant examples to support the identified themes. Results: Three key themes and nine subthemes were identified. Hegemonic perspectives were found in the themes (i) Extension of urban practice and (ii) Austerity, particularly in the Global North. Non‐urban services were typically extended to non‐urban contexts underpinned by austerity and neoliberal values such that non‐urban persons and their context were problematised rather than service or funding design. A counter‐hegemonic perspective was found in the theme (iii) Responses to situational realities more commonly in Global South publications, which valued non‐urban contexts, and focussed on developing non‐urban communities and promoting justice. Conclusion: The hegemonic paradigm links occupational therapy services with neoliberal notions of individualism, private provision of care, and efficiency/market value, rather than the occupational therapy values for justice. The profession must consider our role in perpetuating injustice for non‐urban people and consider if and how more contextually tailored counter hegemonic place‐based paradigms can be developed from and with regional, rural, and remote practice. [ABSTRACT FROM AUTHOR]

Humanoid tactility has been boosting robotic intelligence in object recognition, dexterous manipulation, and human–robot interaction. For many artificial tactile sensors, especially those based on optical principles, inflexibility, bulkiness, and monomodality limit their potential to function as humanoid skins. Herein, by embedding lab‐made optical nanofibers (ONFs) into elastomeric films, soft, flexible, thin (around 500 μm, similar to human skin), and multimodal (force and thermosensitive) robotic skins are achieved. These superior characteristics arise from the low flexural rigidity and large evanescent field of ONFs, due to their subwavelength diameters (down to 450 nm). By tuning light wavelength, ONF diameter, and skin thickness, variable sensitivities and sensing ranges for both force and temperature are reported. Depending on different sensing requirements, special modules can be further assembled on the ONF skins for various surface properties, including hardness, texture, and thermal conductivity. The ONF skins can enable a commercial robot to emulate human behaviors, including adaptive grasping of flimsy objects, contactless temperature measurement, and even the perception of leaf veins. It is anticipated that these ONF skins could offer a unique solution in multiple intelligent systems such as robotics, prosthetics, human–machine interface and wearable devices. [ABSTRACT FROM AUTHOR]

We present the first gridded and temporally continuous quantitative pollen-based plant-cover reconstruction for temperate and northern subtropical China over the Holocene (11.7 ka to present) obtained by applying the Regional Estimates of VEgetation Abundance from Large Sites (REVEALS) model. The objective is to provide a dataset of pollen-based land cover for the last ca. 12 millennia that is suitable for palaeoclimate modelling and for the evaluation of simulated past vegetation cover from dynamic vegetation models and anthropogenic land-cover change (ALCC) scenarios. The REVEALS reconstruction was achieved using 94 selected pollen records from lakes and bogs at a 1 ∘ × 1 ∘ spatial scale and a temporal resolution of 500 years between 11.7 and 0.7 ka and in three recent time windows (0.7–0.35 ka, 0.35–0.1 ka, and 0.1 ka to present). The dataset includes REVEALS estimates of cover and their standard errors (SEs) for 27 plant taxa in 75 1 ∘ × 1 ∘ grid cells distributed within the study region. The 27 plant taxa were also grouped into 6 plant functional types and 3 land-cover types (coniferous trees CT, broadleaved trees BT, and C 3 herbs/open land (C 3 H/OL)), and their REVEALS estimates of cover and related SEs were calculated. We describe the protocol used for the selection of pollen records and the REVEALS application (with parameter settings) and explain the major rationales behind the protocol. As an illustration, we present, for eight selected time windows, gridded maps of the pollen-based REVEALS estimates of cover for the three land-cover types (CT, BT, and C 3 H/OL). We then discuss the reliability and limitations of the Chinese dataset of Holocene gridded REVEALS plant cover, and its current and potential uses. The dataset is available at the National Tibetan Plateau Data Center (TPDC; Li, 2022; 10.11888/Paleoenv.tpdc.272292). [ABSTRACT FROM AUTHOR]

Reconstructing historical land use and land cover change using explicit temporal, quantitative, and spatial information is not only the prerequisite for simulating long-term climate change and ecological effects but is also a scientific basis for comprehensively understanding the process and mechanism of anthropogenic land use alterations. Considering changes in historical borders and administrative divisions, a provincial cropland area dataset for China over the past millennium was created on the basis of existing estimations since the Song Dynasty. Land suitability for cultivation was then assessed by incorporating altitude, slope, soil texture, and the maximum potential productivity of climate. Subsequently, a gridding allocation model for cropland was constructed, and the provincial cropland area for 24 years over the past millennium was allocated into grids with a resolution of 10 km. The cropland area in China increased from 3.71×107 ha in AD 1000 to 12.92×107 ha in AD 1999, with a peak of 13.50×107 ha in AD 1980. The total cropland area in China showed fluctuating increasing trends that can be divided into three phases: fluctuation without notable net change for AD 1000–1290, slow increase for AD 1290–1661, and rapid increase for AD 1661–1999. Spatially, cropland intensified in the middle-lower reaches of the Yellow and Yangtze Rivers and expanded to mountainous and frontier areas over the last millennium. Specifically, over the entire period, the fractional cropland areas (FCAs) in the middle-lower reaches of the Yellow and Yangtze Rivers increased by 1.4 and 0.8 times, respectively. Since the mid-Qing Dynasty, large-scale land reclamation expanded to areas of low reclamation in southwest and northeast China. The FCAs for southwest and northeast China increased from 2.13% and 0.55% in AD 1661 to 18.00% and 26.61% in AD 1999, respectively. For AD 1661–1999, the proportion of cropland increased by 55% in the hills and low mountains and 27% in the middle and high mountains. The comparison with remote sensing cropland data shows that the grid cells with absolute differences of 0–10% accounted for 70.35% of all grid cells, while grids with differences exceeding 60% accounted for only 0.83%. This finding indicates that the reconstruction method is feasible, and the reconstruction results objectively reveal the historical spatiotemporal changes in cropland. [ABSTRACT FROM AUTHOR]

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Understanding long-term soil and landscape evolution can help us understand the threats to current-day soils, landscapes and their functions. The temporal evolution of soils and landscapes can be studied using geochronometers, such as optically stimulated luminescence (OSL) particle ages or radionuclide inventories. Also, soil–landscape evolution models (SLEMs) can be used to study the spatial and temporal evolution of soils and landscapes through numerical modelling of the processes responsible for the evolution. SLEMs and geochronometers have been combined in the past, but often these couplings focus on a single geochronometer, are designed for specific idealized landscape positions, or do not consider multiple transport processes or post-depositional mixing processes that can disturb the geochronometers in sedimentary archives. We present ChronoLorica, a coupling of the soil–landscape evolution model Lorica with a geochronological module. The module traces spatiotemporal patterns of particle ages, analogous to OSL ages, and radionuclide inventories during the simulations of soil and landscape evolution. The geochronological module opens rich possibilities for data-based calibration of simulated model processes, which include natural processes, such as bioturbation and soil creep, as well as anthropogenic processes, such as tillage. Moreover, ChronoLorica can be applied to transient landscapes that are subject to complex, non-linear boundary conditions, such as land use intensification, and processes of post-depositional disturbance which often result in complex geo-archives. In this contribution, we illustrate the model functionality and applicability by simulating soil and landscape evolution along a two-dimensional hillslope. We show how the model simulates the development of the following three geochronometers: OSL particle ages, meteoric 10 Be inventories and in situ 10 Be inventories. The results are compared with field observations from comparable landscapes. We also discuss the limitations of the model and highlight its potential applications in pedogenical, geomorphological or geological studies. [ABSTRACT FROM AUTHOR]

Load carriage (LC) refers to the use of personal protective equipment (PPE) and/or load‐bearing apparatus that is mostly worn over the thoracic cavity. A commonplace task across various physically demanding occupational groups, the mass being carried during LC duties can approach the wearer's body mass. When compared to unloaded exercise, LC imposes additional physiological stress that negatively impacts the respiratory system by restricting chest wall movement and altering ventilatory mechanics as well as circulatory responses. Consequently, LC activities accelerate the development of fatigue in the respiratory muscles and reduce exercise performance in occupational tasks. Therefore, understanding the implications of LC and the effects specific factors have on physiological capacities during LC activity are important to the implementation of effective mitigation strategies to ameliorate the detrimental effects of thoracic LC. Accordingly, this review highlights the current physiological understanding of LC activities and outlines the knowledge and efficacy of current interventions and research that have attempted to improve LC performance, whilst also highlighting pertinent knowledge gaps that must be explored via future research activities. [ABSTRACT FROM AUTHOR]

AlSi casting alloys combine excellent castability with high strength. Hence, this group of alloys is often used in the automotive sector. The challenge for this application is the brittle character of these alloys which leads to cracks during joint formation when mechanical joining technologies are used. A rise in ductility can be achieved by a considerable increase in the solidification rate which results in grain refinement. High solidification rates can be realized in twin–roll casting (TRC) by water‐cooled rolls. Therefore, a hypoeutectic EN AC–AlSi9 (for European Norm ‐ aluminum cast product) is manufactured by the TRC process and analyzed. Subsequently, joining investigations are performed on castings in as‐cast and heat‐treated condition using the self‐piercing riveting process considering the joint formation and the load‐bearing capacity. Due to the fine microstructure, the crack initiation can be avoided during joining, while maintaining the joining parameters, especially by specimens in heat treatment conditions. Furthermore, due to the extremely fine microstructure, the load‐bearing capacity of the joint can be significantly increased in terms of the maximum load‐bearing force and the energy absorbed. [ABSTRACT FROM AUTHOR]

The Al–9Si–0.3Fe–0.15Mn alloy was chosen as the base alloy, 0.2Mo and 0.2Zr were added in combination (0.2Mo+0.2Zr) to the base alloy to maintain the ductility and improve the strength in tensile properties. The 0.2Mo+0.2Zr addition alloy showed improvement in both ultimate tensile strength (σUTS) (160 MPa) and fracture strain (εf) (7.1%) at the as-cast conditions, compared with those (145 MPa, 6.1%) of the base alloy. The increment in the σUTS and εf by 8% and 14%, respectively, was obtained by 0.2Mo+0.2Zr addition. The eutectic α-Al with the smallest minimum nanoindentation hardness (HIT, min), showing high Al or low ΔMkeα due to heavy micro-segregation existed as a continuous phase in the 0.2Mo+0.2Zr addition alloy led to improvement in ductility. The size of the cell structure caused by the dense tangles of dislocations was about 250 nm, which corresponded to a similar size to the high Al or low ΔMkeα regions in the 0.2Mo+0.2Zr addition alloy. It was found on the basis of improvement in tensile properties that both usage of the gravity casting method and the addition of Mo and Zr, suggested the possibility for the as-cast application because the eutectic Si particles were refined, and the eutectic α-Al phase was characterized by high Al content or low ΔMkeα region caused by micro-segregation of the Mo and Zr atoms. The inhomogeneity eutectic grains including IMCs acted as the harmonic structure for the improvement in both strength and ductility. [ABSTRACT FROM AUTHOR]

Aluminum (Al) containing Fe–Mn–C–Al steel exhibits lightweight and outstanding mechanical properties, bringing considerable applications in vehicle, airplane, and mining industries as structural materials and components. The addition of C and Al elements into Fe–Mn iron matrix, following with subsequent heat treatment, plays an important role in microstructure controlling, such as single phase (austenite structure) or duplex phases (mixing with ferritic and austenite) matrix, as well as the short range order and κ‐carbide precipitation. These microstructural evolutions considerably influence the mechanical properties of low‐density steel, especially of the work hardening, tribological, cryogenic, and hydrogen embrittlement performance. The current article introduces the progress of alloying and heat treatment, as well as the subsequent heat treatment effects on microstructural evolution and mechanical properties of Al‐containing low‐density steel. The recent research progress on Al‐containing low‐density steel shall provide a valuable source of ideas for high‐quality, low‐density steel design, and engineering applications. [ABSTRACT FROM AUTHOR]

In many alloy systems, the segregation and strengthening of the solute atoms are caused by mechanical and chemical contributions. To uncover the origins of segregation behaviors and strengthening behaviors of the solute atoms Cd, Si, Sc and Zr at (001)α-Al//(001)′ and (010)α-Al//(010)′ interfaces, first-principles calculations were conducted. Results show that the chemical contribution primarily dominates the oscillatory segregation behaviors of Cd, Si, Sc and Zr on the Al matrix side. The oscillatory segregation behaviors of Cd, Si, Sc and Zr on the ′ side are mainly governed by both chemical and mechanical contributions. The segregation tendency of Cd at the (001)α-Al//(001)′ interface (or (010)α-Al//(010)′ interface) throughout the platelets is small (or strong) because the charge accumulation between Cd and the host atoms is weak (or significant). The segregation trend of Sc (or Zr) on the Al matrix side at the (001)α-Al//(001)′ and (010)α-Al//(010)′ interfaces is strong, which is attributed to significant charge accumulation between Sc (or Zr) and the host atoms. Si exhibits a favorable segregation tendency on the ′ side at both the (001)α-Al//(001)′ and (010)α-Al//(010)′ interfaces, which is ascribed to significant charge accumulation between Si and the host atoms. With the increase of Si, Sc and Zr coverage, the segregation tendencies of Si, Sc and Zr enhance. The segregation tendency of Cd decreases with the increase of Cd coverage. The first-principles tensile test for the interface was conducted. The work of dislocation emission was computed. Results show that the strengthening effects of solute atoms on the interface are primarily dominated by the chemical contribution. Sc (or Zr) segregation leads to an increase in the strength of the interface, which is majorly attributed to a strong electronic interaction between Sc (or Zr) and the host atoms. Cd segregation causes a weakening effect on the interface because of the weak electronic interaction between Cd and the host atoms. The ductility of the (001)α-Al//(001)′ interface with the Sc (or Zr) is more significant than that with the Cd (or Si). This work provides a strategy for improving the mechanical properties of the Al–Cu alloys. [ABSTRACT FROM AUTHOR]

Hox genes encode transcription factors that play an important role in establishing the basic body plan of animals. In Drosophila, Antennapedia is one of the five genes that make up the Antennapedia complex (ANT-C). Antennapedia determines the identity of the second thoracic segment, known as the mesothorax. Misexpression of Antennapedia at different developmental stages changes the identity of the mesothorax, including the muscles, nervous system, and cuticle. In Drosophila, Antennapedia has two distinct promoters highly regulated throughout development by several transcription factors. Antennapedia proteins are found with other transcription factors in different ANTENNAPEDIA transcriptional complexes to regulate multiple subsets of target genes. In this review, we describe the different mechanisms that regulate the expression and function of Antennapedia and the role of this Hox gene in the development of Drosophila., (© 2023 The Authors. genesis published by Wiley Periodicals LLC.)

Peripheral chemoreceptors (PChRs), because of their strategic localization at the bifurcation of the common carotid artery and along the aortic arch, play an important protective role against hypoxia. Stimulation of PChRs evokes hyperventilation and hypertension to maintain adequate oxygenation of critical organs. A relationship between increased sensitivity of PChRs (hyperreflexia) and exercise intolerance (ExIn) in patients with heart failure (HF) has been previously reported. Moreover, some studies employing an acute blockade of PChRs (e.g., using oxygen or opioids) demonstrated improvement in exercise capacity, suggesting that hypertonicity is also involved in the development of ExIn in HF. Nonetheless, the precise mechanisms linking dysfunctional PChRs to ExIn remain unclear. From the clinical perspective, there are two main factors limiting exercise capacity in HF patients: subjective perception of dyspnoea and muscle fatigue. Both have many determinants that might be influenced by abnormal signalling from PChRs, including: exertional hyperventilation, oscillatory ventilation, ergoreceptor oversensitivity, and augmented sympathetic tone. The latter results in reduced muscle perfusion and altered muscle structure. In this review, we intend to present the milieu of abnormalities tied to malfunctioning PChRs and discuss their role in the complex relationships leading, ultimately, to ExIn. [ABSTRACT FROM AUTHOR]

Studies of Fe‐contaminated Al‐based scraps have drawn attention for years. However, little has been researched about the effects of cobalt (Co) and nickel (Ni) additions to contaminated scraps both under slow solidification (directional solidification, DS) and fast solidification regime (copper mold centrifugal casting, CC). As such, the current study examines a representative low‐alloy Al–Si chemistry from industrial scraps, i.e., the Al–7%Si–0.6%Fe–0.35%Cu–0.25%Zn (% by weight). This alloy is changed independently using Ni and Co. It is observed that a mixture of uneven distributed α and β Fe‐bearing particles prevails for all tested alloys and solidification conditions. The coexistence of both phases agrees with the charts proposed by Gorny's work for the range of secondary dendritic spacing, λ2, observed. Although the Fe‐containing particles are smaller for fast‐solidified samples, they still maintain the acute morphology and, in some cases, the Chinese script shape. This results in a reduction in ductility of the order of 65% for the nonmodified and Ni‐modified samples considering mean λ2 varying from 20 μm (DS) to 6.5 μm (CC), despite improvements in mechanical strength. Furthermore, addition of Co results in a higher number of Fe‐based particles within the microstructure. In this case, the largest particle/α‐Al interfacial area results in slightly poor ductility (~6–8%) and higher strength (175–205 MPa), with less ductility loss when DS and CC samples are compared. [ABSTRACT FROM AUTHOR]

A systematic study of structure and hardening of two‐phase Al–8% Ca, Al–10% Ce, and Al–10% La eutectic aluminum alloys under high‐pressure torsion (HPT) has been carried out. HPT leads to an increase in microhardness as a result of the formation of a nanocrystalline structure with a high density of crystal defects in the Al–8% Ca alloy and a nano‐ and submicrocrystalline structure with a low density of crystal defects in the Al–10% Ce and Al–10% La alloys, as well as the eutectic particle refinement in all alloys. The predominant crystallite sizes after HPT through five turns are 70–210, 60–120, and 25–45 nm, respectively, in the Al–10% La, Al–10% Ce, and Al–8% Ca alloys. The change in the shape of the curve of the microhardness distribution over the samples' surface with an increase in the number of turns from 1 to 5 is different for three alloys. The results demonstrate the ultrafine‐grained microstructure development varied depending on the binary alloy systems. Initial as‐cast eutectic particles have a significant effect on the structure and hardening of alloys through their morphology, volume fraction, hardness, and orientational ratio with the aluminum base. [ABSTRACT FROM AUTHOR]

Soils and landscapes can show complex, nonlinear evolution, especially under changing climate or land use. Soil-landscape evolution models (SLEMs) are increasingly equipped to simulate the development of soils and landscapes over long timescales under these changing drivers, but provide large data output that can be difficult to interpret and communicate. New tools are required to analyze and visualize large model outputs. In this work, I show how spatial and temporal trends in previously published model results can be analyzed and visualized with evolutionary pathways, which are possible trajectories of the development of soils. Simulated differences in rainfall and land use control progressive or regressive soil development and convergence or divergence of the soil pattern. These changes are illustrated with real-world examples of soil development and soil complexity. The use of evolutionary pathways for analyzing the results of SLEMs is not limited to the examples in this paper, but they can be used on a wide variety of soil properties, soil pattern statistics and models. With that, evolutionary pathways provide a promising tool to analyze and visualize soil model output, not only for studying past changes in soils, but also for evaluating future spatial and temporal effects of soil management practices in the context of sustainability. [ABSTRACT FROM AUTHOR]

Introduction: Advances in cancer treatment over the last decade have led to increased survival rates. As a result, survivors are living longer with and beyond cancer, often with greater levels of morbidity. Occupational therapists, with their focus on remedial and compensatory strategies to improve function and participation, are well suited to assess and intervene with this population. Despite this, little research exists to demonstrate the efficacy of interventions and value of the occupational therapy role. This systematic review aimed to review how and when occupational therapists provide services for adult patients with cancer and identify where they add the most value. Methods: A systematic search was conducted of six electronic databases. Eligible studies reported on occupational therapy interventions targeting management of cancer symptoms, rehabilitation or environmental modifications for adult cancer patients discharged from acute hospital services. Data extraction and quality assessment were undertaken by two reviewers. Narrative synthesis summarised the attributes and treatment outcomes of each intervention. Results: Nine articles were included from a total of 309 articles retrieved. Eight different interventions were reported for people with cancer (n = 531). Small sample sizes and methodological quality precluded any formal analysis; however, intervention components that showed positive results were person‐centred, individualised and included regular monitoring and flexibility in care, with input from multidisciplinary health professionals. Therapists also need to reflect upon the optimal duration of interventions and selection of outcome measures that specifically match intervention components. Conclusion: Despite inconclusive support of any particular type of intervention, this systematic review identified several successful intervention components for occupational therapists working with people with or beyond cancer. Overall, findings suggest that monitored tailored programmes compensating for fluctuations in a patient's condition have efficacy to improve patient outcomes and should be considered when delivering intervention with patients post hospital discharge. [ABSTRACT FROM AUTHOR]

Cropland greatly impacts food security, energy supply, biodiversity, biogeochemical cycling, and climate change. Accurately and systematically understanding the effects of agricultural activities requires cropland spatial information with high resolution and a long time span. In this study, the first 1 km resolution global cropland proportion dataset for 10 000 BCE–2100 CE was produced. With the cropland map initialized in 2010 CE, we first harmonized the cropland demands extracted from the History Database of the Global Environment 3.2 (HYDE 3.2) and the Land-Use Harmonization 2 (LUH2) datasets and then spatially allocated the demands based on the combination of cropland suitability, kernel density, and other constraints. According to our maps, cropland originated from several independent centers and gradually spread to other regions, influenced by some important historical events. The spatial patterns of future cropland change differ in various scenarios due to the different socioeconomic pathways and mitigation levels. The global cropland area generally shows an increasing trend over the past years, from 0×106km2 in 10 000 BCE to 2.8×106km2 in 1500 CE, 6.2×106km2 in 1850 CE, and 16.4×106km2 in 2010 CE. It then follows diverse trajectories under future scenarios, with the growth rate ranging from 16.4 % to 82.4 % between 2010 CE and 2100 CE. There are large area disparities among different geographical regions. The mapping result coincides well with widely used datasets at present in both distribution pattern and total amount. With improved spatial resolution, our maps can better capture the cropland distribution details and spatial heterogeneity. The spatiotemporally continuous and conceptually consistent global cropland dataset serves as a more comprehensive alternative for long-term earth system simulations and other precise analyses. The flexible and efficient harmonization and downscaling framework can be applied to specific regions or extended to other land use and cover types through the adjustable parameters and open model structure. The 1 km global cropland maps are available at 10.5281/zenodo.5105689 (Cao et al., 2021a). [ABSTRACT FROM AUTHOR]

We produced a reconstruction of mid-19th-century building structure locations in former Galicia and Austrian Silesia (parts of the Habsburg Monarchy), which are located in present-day Czechia, Poland, and Ukraine and cover more than 80 000 km 2. Our reconstruction was based on a homogeneous series of detailed Second Military Survey maps (1:28800) that were the result of a cadastral mapping (1:2880) generalization. The dataset consists of two types of building structures based on the original map legend – residential and outbuildings (mainly farm-related buildings). The dataset's accuracy was assessed quantitatively and qualitatively by using independent data sources and may serve as an important input in studying long-term socioeconomic processes and human–environmental interactions or as a valuable reference for continental settlement reconstructions. The dataset is available at 10.17632/md8jp9ny9z.2 (Kaim et al., 2020a). [ABSTRACT FROM AUTHOR]

The aim of this work is to fabricate aluminum, boron carbide (B4C) based aluminum matrix composites (AMCs) using easy and cost effective powder metallurgy (P/M) route. Here, Al–Mg–Si composites having different weight fractions of B4C (3.5,7.0,10.5,14.0 and 17.5 wt%) were synthesized to study the dry sliding wear behavior with respect to automobile brake pad material. The surface morphology and elemental composition of fabricated composite material were characterized by Scanning Electron Microscope (SEM) and energy dispersive x-ray spectroscopy (EDS) respectively. Further, dry sliding wear tests were conducted with respect to i.e. applied loads, sliding distances and reinforcements for the performance analysis of synthesized AMCs. A linear regression model was used to optimize the control factors. Furthermore, explore the effects of reinforcements on density, Vickers hardness, wear rate and worn out surface morphology. Further, the analysis also revealed the critical wear mechanisms with their wear debris for improvement in the AMCs. The hardness of aluminum composite (17.5% B4C/Al–Mg–Si) showed 54.15% higher value than matrix alloy. Furthermore, it was observed that AMCs showed significant improvement on the various factors e.g., applied load (L), sliding distances (SD) and reinforcements (R) than that of aluminium matrix alloy. [ABSTRACT FROM AUTHOR]

Samples built by the additive manufacturing experience various thermal cycles during the process. This, as a result, defines the final microstructure of the samples. Herein, the dissolution of θ‐Al2Cu precipitate along the building direction during electron beam melting process is aimed at. Induced thermal cycles cause the layers to experience critical temperatures. The results show that the average fraction area of precipitates is decreased from 3.34% to 2.63% and finally to 2.02% by moving along the building direction from the top to the bottom. This is due to the fact that the first deposited layers are kept at temperatures more than 520 °C for longer times, which is higher than the critical temperature of Al2Cu dissolution. Because of the solubility limit of Cu in the matrix, precipitates are not fully dissolved. Comparing the ratio of the integration area of the strongest θ diffraction peak to that of the α matrix at different locations, the dissolution is also confirmed by X‐ray diffraction (XRD) results. The results of the tensile test also demonstrate a decline of about 29% in the mechanical performance by moving from the top to the bottom, which can be attributed to the precipitates' dissolution and grain coarsening. [ABSTRACT FROM AUTHOR]

A warm forming process with a simultaneous retrogression heat treatment, termed retrogression forming, can achieve good formability in high-strength aluminum alloys and recover their high strength through a single reaging heat treatment after forming. Tensile data from two commercial aluminum alloy sheet materials, AA7075-T6 and AA6013-T6, are presented for conditions suitable to retrogression forming. AA7075-T6 sheet was tested at temperatures from 180 °C to 220 °C and strain rates from 3.2 × 10−3 to 10−1 s−1. AA6013-T6 sheet was tested from 230 °C to 250 °C and 3.2 × 10−3 to 10−1 s−1. Both materials exhibit nearly steady-state flow at these temperatures and produce a modest strain-rate sensitivity of m = 0.039. The activation energies for plastic flow under these conditions are 221 kJ/mol for AA7075-T6 and 253 kJ/mol for AA6013-T6. Test data are used to construct predictive models for flow stress as a function of temperature and strain rate. AA7075-T6 demonstrates an excellent potential for retrogression forming at 200 °C and strain rates up to 10−1 s−1 if time at temperature is held to under 12 minutes. AA6013-T6 exhibits a modest potential for retrogression forming at 240 °C and strain rates up to 10−1 s−1 if time at temperature is held to under 7 minutes. [ABSTRACT FROM AUTHOR]

Cold spray additive manufacturing (CSAM) is an innovative method for producing freeform and near-net-shape components with high deposition rates and low thermal gradients. The CSAM fabrication technology used here targets low cost using air as a carrier gas, aiming to compete with casting for small production runs. However, incomplete interparticle bonding and intense plastic deformation during supersonic impact of deposition results in cold worked, non-ductile materials. This exploratory study investigates heat treatments of CSAM aluminum 6061 for interparticle boundary healing and compares the CSAM results to cast aluminum 356.0 T6. CSAM tensile specimens in four heat treatment groups were compared to a non-heat-treated control. Three-stage (sintering, solutionizing and aging) heat treatments were performed in air and a further group in a carbon monoxide atmosphere. Microstructural evolution and mechanical performance were measured. Heat treatment resulted in increased UTS, YS and reduced porosity and comparable mechanical properties (up to 280MPa and 8% strain to failure) to cast aluminum 356.0 T6. Although the heat-treated CSAM microstructures exhibited clear signs of sintering including densification and particle and pore coalescence, the solutionizing and aging processes appeared incomplete. Further tailoring heat treatments for CSAM aluminum 6061 could add strength while maintaining its custom manufacturing ability. [ABSTRACT FROM AUTHOR]

Applying additive manufacturing (AM) technologies to the fabrication of aluminum automotive components, with an optimized design, may result in improved vehicle light weighting. However, the post-process heat treatment of such alloys has to be customized for the particular AM microstructure. The present study is aimed at investigating the effect of different heat treatments on the microstructure, hardness and residual stress of the A357 (AlSi7Mg0.6) heat-treatable alloy produced by laser-based powder bed fusion (LPBF, also known as selective laser melting). There are two major issues to be addressed: (1) relieving the internal residual stress resulting from the process and (2) strengthening the alloy with a customized heat treatment. Therefore, stress-relief annealing treatment, direct aging of the as-built alloy and a redesigned T6 treatment (consisting of a shortened high-temperature solution treatment followed by artificial aging) were examined. Comparable hardness values were reached in the LPBF alloy with optimized direct aging and T6 treatments, but complete relief of the residual stress was obtained only with T6. Microstructural analyses also suggested that, because of the supersaturated solid solution, different phenomena were involved in direct aging and T6 treatment. [ABSTRACT FROM AUTHOR]

In this study, the use of electrical resistance (ER) sensors to monitor the corrosion of Al94Cu6 alloy is assessed and compared with 2024‐T3 coupons. Under uniform corrosion, a good correlation was found between the ER sensors and mass loss on coupons. Three different chloride depositions are studied: (i) pre‐contamination with dry/wet cycles, (ii) Volvo standard accelerated corrosion test and (iii) neutral salt spray test. The obtained results show good reproducibility of the ER sensors under all tested conditions. This suggests that ER sensors more levelled the effect of localised corrosion through a large surface evaluation compared with cross‐sections. The corrosion thickness obtained with the ER sensors does not correspond to the mean depth obtained by cross‐sections. This can be explained by the distribution and size of the localised corrosion events according to a finite element model proposed. The ER method allows obtaining useful real‐time corrosion data for the understanding of the corrosion mechanisms and the development of accelerated tests. The chloride concentration, the frequency of salt application and wet/dry cycles have a strong influence on the corrosion rate of aluminium alloys. [ABSTRACT FROM AUTHOR]

Recently, electron beam machining technology has been used in various ways depending on the industrial field. It is used in technologies in the fields of shipbuilding, aerospace, and transportation. In the case of the existing electron beam machining technology, a technology for welding or joining two materials was proposed. In this paper, in order to perform electron beam drilling, a multi-hole is created by increasing the instantaneous vaporization pressure during electron beam machining through a vaporized amplification sheet. A vaporized amplification sheet was prepared for electron beam drilling. The vaporized amplification sheet was made of a 1:3.25 combination of silicone and brass powder. Also, in order to bond the produced vaporized amplification sheet to the SUS 304 stainless steel, a primer was applied on the surface of the metal material to firmly bond the two materials with different properties. If the bonding is weak, the effectiveness decreases due to pressure leakage during electron beam machining. Multi-holes were processed using the fabricated material to fix an acceleration voltage of 120 kV and a current of 12 mA. Also, to compare the multi-hole shape and the processing result, the comparison was performed according to the exposure time of the electron beam. The lower the exposure time, the more fine holes were secured, and as the exposure time increased, the molten pool phenomenon occurred, and processing was not performed in the experimental results. [ABSTRACT FROM AUTHOR]

This study suggests a new way to modify the size and morphology of Al-Fe phases in modified AA 7075 by using an Fe-Mn solid solution powder as the precursor. When Fe and Mn are added in the form of a solid solution, the diffusion of Fe and Mn toward the Al is delayed, thus altering the chemical composition and morphology of the precipitates. The fine, spherical precipitates are found to provide a good balance between strength and ductility compared to the case where Fe and Mn are separately added. [ABSTRACT FROM AUTHOR]

As globalization has become a defining issue for business and society, an increasing amount of research has examined how multicultural experiences affect a variety of psychological and organizational outcomes.We define "multicultural experiences" as exposure to or interactions with elements or members of a different culture(s). We then provide a comprehensive review of the literature and detail how multicultural experiences impact intrapersonal, interpersonal, and organizational outcomes, including creativity, psychological adjustment, intergroup bias, trust, morality, leadership effectiveness, and individual or firm performance, exploring key mechanisms and boundary conditions that have also emerged. We then present a new theoretical framework--the "Structure--Appraisal Model of Multicultural Experiences"--that organizes the overall pattern of findings and provides a roadmap for future research. The structure part of our model proposes that deeper multicultural experiences produce integrative processes that transformintrapersonal cognition, whereas broader multicultural experiences activate comparative processes that influence interpersonal attitudes and behaviors. The appraisal part of our model suggests that these intrapersonal and interpersonal effects are only likely to occur when appraisals of one's multicultural experiences are positive rather than negative. We conclude by discussing practical implications for individuals and organizations, as well as future directions for researchers to consider exploring. [ABSTRACT FROM AUTHOR]

Weight reduction is a major trend in the development of automotive, marine, and aerospace industry. Al alloys are the ideal choice for the lightweight design because of their superior mechanical properties and small mass density. In recent years, research results have demonstrated that plastic processing at cryogenic temperature can improve the mechanical properties of Al alloys. Herein, the mechanical properties of Al alloys at cryogenic environment as well as at room temperature are compared, and then the main progress is introduced in the development of fabrication of high‐performance Al alloys using cryo‐forming methods, such as cryorolling, asymmetric cryorolling, cryo‐extrusion, and cryo‐forging, with subsequent heat treatment. The grain refinement mechanism and the strengthening mechanism of Al alloys during various cryo‐forming processes are discussed. Finally, the potential development prospects of future researches in this field are proposed. [ABSTRACT FROM AUTHOR]

With a sample of 4,065 bonds issued by 63 banks from 12 euro area countries during 2013–2017, this study investigates how introducing bail‐in regulation has influenced bond yields in secondary markets, by distinguishing between non‐bail‐inable and different classes of bail‐inable bonds. The bail‐in risk premium does not follow the hierarchy of risk; it is stronger for less risky bonds. The effect on the spread between senior unsecured and non‐bail‐inable bonds is much higher than for subordinated bonds. Regarding subordinated bonds, the impact is higher for securities excluded from regulatory capital than for those included. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mining & Metallurgy. Section B: Metallurgy is the property of Journal of Mining & Metallurgy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was undertaken to investigate the tensile properties and hot tearing susceptibility of cast Al-Cu alloys containing excess Fe (up to 1.5wt%) and Si (up to 2.5wt%). According to the results, the optimum tensile properties and hot tearing resistance were achieved at Fe/Si mass ratio of 1, where the α-Fe phase was the dominant Fe compound. Increasing the Fe/Si mass ratio above unity increased the amounts of detrimental β-CuFe platelets in the microstructure, deteriorating the tensile properties and hot tearing resistance. Decreasing the mass ratio below unity increased the size and fraction of Si needles and micropores in the microstructure, also impairing the tensile properties and hot tearing resistance. The investigation of hot-torn surfaces revealed that the β-CuFe platelets disrupted the tear healing phenomenon by blocking interdendritic feeding channels, while the a-Fe intermetallics improved the hot tearing resistivity due to their compact morphology and high melting point. [ABSTRACT FROM AUTHOR]

Humans act at worldwide scale as a growing geomorphic agent since mid‐Holocene (8,200–4,200 y BP) through the pervasive impacts of domestication, deforestation, agriculture, urbanization, and mining. The concept of Anthropocene has been introduced exactly to indicate the timespan in which humans have joined with other natural forces in impacting the outermost shell of the planet and the biosphere. Soils, which are the Earth's skin, are sensitive archives of any major human‐induced local to global change. Especially when buried, soils can permanently preserve the primordial traces of a significant impact of man on the environment, which occurred at different times and rates in different areas. As a result, we assert that the oldest "anthropogenic" soils from all around the world collectively are an appropriate marker for the diachronous dawn of an early Anthropocene. [ABSTRACT FROM AUTHOR]

Good electrical conductivity, mechanical properties and electrochemical performance are required for aluminum alloys acting as cathode current collectors of lithium ion batteries (LIBs). The effect of La alloying on the microstructure, mechanical properties and the electrochemical performance of Al-Fe-Mn alloys were characterized by optical microscopy, X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, tensile test, conductivity test and Tafel polarization curve test. The experiment results showed that Al13Fe4 and Al6(Mn, Fe) precipitates tended to nucleate and grow along the grain boundaries. The addition of La to the Al-Fe-Mn alloy could help to refine grains and spheroidize secondary phases. These changes in microstructure could improve the tensile strength and elongation at room temperature and a high temperature of 125°C and enhance the corrosion resistance of the alloy. However, the spheroidized precipitates tended to aggregate in the alloy with 0.15 wt.% La and this uneven aggregation resulted in a decrease in tensile strength and elongation in comparison to the alloy with 0.1 wt.% La, which suggested an optimal La content for the Al-Fe-Mn alloy. [ABSTRACT FROM AUTHOR]

Islet transplantation is emerging as a therapeutic option for type 1 diabetes, albeit, only a small number of patients meeting very stringent criteria are eligible for the treatment because of the side effects of the necessary immunosuppressive therapy and the relatively short time frame of normoglycemia that most patients achieve. The challenge of the immune‐suppressive regimen can be overcome through microencapsulation of the islets in a perm‐selective coating of alginate microbeads with poly‐l‐lysine or poly‐ l‐ornithine. In addition to other issues including the nutrient supply challenge of encapsulated islets a critical requirement for these cells has emerged as the need to engineer the microenvironment of the encapsulation matrix to mimic that of the native pancreatic scaffold that houses islet cells. That microenvironment includes biological and mechanical cues that support the viability and function of the cells. In this study, the alginate hydrogel was modified to mimic the pancreatic microenvironment by incorporation of extracellular matrix (ECM). Mechanical and biological changes in the encapsulating alginate matrix were made through stiffness modulation and incorporation of decellularized ECM, respectively. Islets were then encapsulated in this new biomimetic hydrogel and their insulin production was measured after 7 days in vitro. We found that manipulation of the alginate hydrogel matrix to simulate both physical and biological cues for the encapsulated islets enhances the mechanical strength of the encapsulated islet constructs as well as their function. Our data suggest that these modifications have the potential to improve the success rate of encapsulated islet transplantation. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Occupational Therapy / Cadernos Brasileiros de Terapia Ocupacional is the property of Cadernos de Terapia Ocupacional da UFSCar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, boron nitride nanotube (BNNT)–reinforced Ti alloy composites with 1 wt% BNNT (3 vol%) are successfully fabricated by spark plasma sintering (SPS). This study addresses two challenges affecting the performance of BNNT–metal matrix composites: i) the dispersion of high‐surface‐energy BNNTs by an ultrasonic‐assisted technique and ii) the control of reactions at the metal/nanotube interface. High‐energy ultrasonic vibrations were effective in the dispersion of entangled BNNTs, and sintering at low (750 °C and 555 MPa) and high (950 °C and 60 MPa) temperature regimes resulted in relative densities of 97% and 99%. Reducing sintering temperatures by up to 35% compared to those used in conventional sintering is effective in minimizing brittle interfacial products. Also, the composites sintered at high‐temperatures/low‐pressure benefit from the rapid densification (10 min) achieved in the SPS process limiting the extent of reactions (TiB2, TiB). Compressive properties show composites sintered at low and high temperatures exhibit increases of 46% and 50% in yield strength, respectively, as compared to the Ti alloy. Strain hardening exponents of 0.8 and 0.5 characterize the capabilities of the composites to arrest plasticity in the presence of BNNTs, reaction phases, and twin boundaries pinning dislocations. This study unravels the potential of a low‐temperature/high‐pressure processing window for Ti‐BNNT composites. [ABSTRACT FROM AUTHOR]