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Smart materials that respond to external stimuli are useful for applications ranging from artificial skin to sensing to cosmetics. Inspired by natural phenomena (self‐healing, shape memory, and shrinking), this work develops a novel smart bio‐composite using sustainable polyurethane (PU) and sugarcane bagasse (SB) waste without using a solvent. PU is synthesized using polycaprolactone (PCL) diol, castor oil (CO) as a polyol, and isophorone diisocyanate (IPDI) as diisocyanate. Composites are prepared using PU and SB in the presence and absence of poly(acrylic acid) (PAA) and are denoted as PBA and PB, respectively. TGA and DSC analysis indicate the broad (−68.4 °C to 192 °C) thermal stability of these materials. PBA and PB composites exhibited relatively fast (20–30 min) self‐healing and high shape fixity ratio (Rf) (70–83%), and shape recovery ratio (Rr) (82–100%) at 60 °C in the air. Furthermore, PBA shows hot water‐responsive rapid 100% shape recovery and also exhibits thermoresponsive shrinkage properties like human skin. PBA lifts a material 13.3±2 % of its original length by utilizing its thermoresponsive shrinking property. These inexpensive materials with self‐healing, shape recovery, high thermal stability, and thermo‐responsive properties are attractive and may be useful in artificial skin, sensor, and coating applications. [ABSTRACT FROM AUTHOR]

A nanofluid refers to a suspension of nanoparticles in a conventional fluid, which finds unique applications in diverse sectors, including engineering, technology, and medicine. When multiple nanoparticles are suspended, it creates a hybrid nanofluid. In this study, we aim to investigate an unsteady flow of hybrid nanofluid over a permeable shrinking inclined rotating disk subjected to heat radiation, magnetohydrodynamics and slip effects. The chosen nanoparticles for this study are alumina (Al2O3) and copper (Cu), incorporated into a base fluid of water (H2O) to create the hybrid nanofluid. An appropriate method of similarity transformation is executed along a set of partial differential equations that were reduced to a system of nonlinear ordinary differential equations, where numerical outcomes were then obtained via bvp4c in MATLAB software, with the influence of various parameters such as unsteadiness parameter, nanoparticle volume fraction, shrinking, radiation, magnetic and velocity slip parameters, shown in tables and figures. Multiple solutions (including dual, upper, and lower branch solutions) are identified for the governing similarity equations. Through the conducted stability analysis, it is determined that the upper branch solutions exhibit stability and physically realizable in practice, while the lower branch solutions are unstable. Our numerical findings showed that dual solutions exist when ε c ≤ ε ≤ - 1 , where ε c < 0 is the critical value of ε for which the boundary value problem poses physical solutions applicable in practice. Yet, the boundary value problem lacks a similarity solution for ε ≤ ε c ≤ 0 , and the complete set of partial differential equations needs to be solved numerically. Improvements in heat transfer rate are observed concerning the radiation parameter, nanoparticle fraction, and shrinking parameter. Furthermore, azimuthal velocity profiles show an increase influenced by velocity slip and magnetic parameters. The non-dimensional physical parameters, including stretching/shrinking, suction, slip, and unsteadiness, are also considered and their effects are presented in figures and tables. [ABSTRACT FROM AUTHOR]

For efficient heating and cooling applications, minimum wall shear stress and maximum heat transfer rate are desired. The current study optimized the local skin friction coefficient and Nusselt number in Al2O3-Cu/water hybrid nanofluid flow over a permeable shrinking rotating disk. First, the governing equations and boundary conditions are solved numerically using the bvp4c solver in MATLAB. Von Kármán's transformations are used to reduce the partial differential equations into solvable non-linear ordinary differential equations. The augmentation of the mass transfer parameter is found to reduce the local skin friction coefficient and Nusselt number. Higher values of these physical quantities of interest are observed in the injection case than in the suction case. Meanwhile, the increase in the magnitude of the shrinking parameter improved and reduced the local skin friction coefficient and Nusselt number, respectively. Then, response surface methodology (RSM) is conducted to understand the interactive impacts of the controlling parameters in optimizing the physical quantities of interest. With a desirability of 66%, the local skin friction coefficient and Nusselt number are optimized at 1.528780016 and 0.888353037 when the shrinking parameter ( λ ) and mass transfer parameter ( S ) are −0.8 and −0.6, respectively. [ABSTRACT FROM AUTHOR]

The use of hybrid nanofluids in practical applications is pivotal for enhanced heat transfer efficiency especially for electronics cooling, and manufacturing processes. This study delves into numerically investigating the unsteady water-based (alumina+copper+titanium dioxide) ternary hybrid nanofluid flow over a permeable biaxial shrinking sheet, considering the influence of thermal radiation. The model, initially formulated as partial differential equations (PDEs), is adeptly transformed into ordinary differential equations (ODEs) via established similarity transformations. Subsequently, a numerical solution employing the finite difference scheme in bvp4c MATLAB unravels the behaviors of crucial physical quantities—across various parameter configurations. Remarkably, this study reveals the presence of two potential solutions, among which only one exhibits physical stability. Notably, the findings underscore the efficacy of enlarging the boundary suction parameter and diminishing thermal radiation for augmenting heat transfer within the specified conditions of ternary hybrid nanofluid. A noteworthy finding of this study reveals that an increase in the boundary suction parameter by 4% leads to a remarkable 9% delay in the boundary layer separation of the ternary hybrid nanofluid, thus maintaining the laminar phase flow. This study offers crucial guidance and insights for researchers and practitioners delving into the mathematical or experimental aspects of ternary hybrid nanofluid dynamics.

The use of hybrid nanofluids in practical applications is pivotal for enhanced heat transfer efficiency especially for electronics cooling, and manufacturing processes. This study delves into numerically investigating the unsteady water-based (alumina+copper+titanium dioxide) ternary hybrid nanofluid flow over a permeable biaxial shrinking sheet, considering the influence of thermal radiation. The model, initially formulated as partial differential equations (PDEs), is adeptly transformed into ordinary differential equations (ODEs) via established similarity transformations. Subsequently, a numerical solution employing the finite difference scheme in bvp4c MATLAB unravels the behaviors of crucial physical quantities—across various parameter configurations. Remarkably, this study reveals the presence of two potential solutions, among which only one exhibits physical stability. Notably, the findings underscore the efficacy of enlarging the boundary suction parameter and diminishing thermal radiation for augmenting heat transfer within the specified conditions of ternary hybrid nanofluid. A noteworthy finding of this study reveals that an increase in the boundary suction parameter by 4% leads to a remarkable 9% delay in the boundary layer separation of the ternary hybrid nanofluid, thus maintaining the laminar phase flow. This study offers crucial guidance and insights for researchers and practitioners delving into the mathematical or experimental aspects of ternary hybrid nanofluid dynamics. • Unsteady ternary hybrid nanofluid over a permeable biaxial shrinking sheet with thermal radiation is studied. • The differential equations are solved using bvp4c in Matlab. • Dual solutions are obtainable but only one solution is stable. • The suction parameter delayed the separation process of the boundary layer. [ABSTRACT FROM AUTHOR]

The purpose of fins or extended surfaces is to increase the dissipation of heat from hot sources into their surroundings. Fins like annular fins, longitudinal fins, porous fins, and radial fins are used on the surface of equipments to enhance the rate of heat transfer. There are many applications of fins, including superheaters, refrigeration, automobile parts, combustion engines, electrical equipment, solar panels, and computer CPUs. Based on a wide range of applications, the effects of stretching/shrinking on a fully wet trapezoidal fin with internal heat generation is investigated. The shooting approach is used to calculate the trapezoidal fin's thermal profile, tip temperature, and efficiency. It is observed that with an increase in the shrinking and wet parameter, the temperature distribution decreases and efficiency increases. On the other hand, when stretching increases, the temperature distribution increases and efficiency diminishes. Using the computed results, it is concluded that shrinking trapezoidal fins improves the effectiveness and performance of the system. [ABSTRACT FROM AUTHOR]

A microdevice that offers glucagon supplements in a safe, non-invasive, and glucose-responsive manner is ideal for avoiding fatal hypoglycemia consequences from insulin overdosage during daily diabetes treatment. However, mold-assisted microfabrication of biomedical materials or devices typically needs high-resolution laser ablation to scale down structural design. In addition, the majority of the polymeric drug delivery materials being used to fabricate devices are dissolvable or deformable in aqueous environments, which restricts washing-based cleaning and purification procedures post shape fixation. This study leverages the design flexibility of 3D printing-assisted mold casting and presents a shrinking microfabrication approach that allows subsequent washing procedures to remove toxic monomer residues during polymerization. The feasibility of this approach is demonstrated by developing a glucose-responsive transdermal glucagon microneedle patch through matrix volume change-mediated release kinetic control. Shown in the type 1 diabetic mouse model, this transdermal patch can reverse the occurrence of hypoglycemia while lowering the risk of monomer residue-induced irritation during treatment. Freeing from the restrain of molding resolution for microstructure design, this shrinking methodology further provides an insight into post-fabrication purifications of biomedical materials.

We conducted an experimental study on the swelling–shrinking characteristic of expansive soil treated with enzyme-induced carbonate precipitation (EICP) using yellow soybean. A series of tests including the free swell test, swelling rate test, swelling pressure test, and shrinking test were conducted on expansive soil specimens with various water contents and equimolar concentrations. The test results showed that EICP-treated expansive soil samples exhibited an obvious reduction in the magnitude of free swelling rate, swelling rate, swelling pressure, and shirking rate compared with the untreated one. This indicates that EICP using yellow soybean can effectively reduce the swell and shrink potential of expansive soil. The free swelling rate consistently decreases with the increasing equimolar concentration. A more remarkable reduction in swelling rate can be observed at a concentration of 1 mol/L compared with a less significant decrease at a higher concentration. The free swelling rate shows an ascending trend first and then a declining tendency with the increase of water content at higher equimolar concentrations. The influences of equimolar concentration and water content on the change of swelling rate for treated samples with applied loading pressures are insignificant. The swelling pressure reduces remarkably with increasing equimolar concentration and then tends to level off. The swelling pressure exhibits an ascending tendency with the increase of water content. The shrinking rate reduces more remarkably with equimolar concentration at first and then increases less remarkably, with an equimolar concentration of 2 mol/L exhibiting the lowest shrinking rate. The soil specimen with higher water content shows a higher value of shrinking rate than that with a lower one. [ABSTRACT FROM AUTHOR]

For efficient heating and cooling applications, minimum wall shear stress and maximum heat transfer rate are desired. The current study optimized the local skin friction coefficient and Nusselt number in Al2O3-Cu/water hybrid nanofluid flow over a permeable shrinking rotating disk. First, the governing equations and boundary conditions are solved numerically using the bvp4c solver in MATLAB. Von Kármán’s transformations are used to reduce the partial differential equations into solvable non-linear ordinary differential equations. The augmentation of the mass transfer parameter is found to reduce the local skin friction coefficient and Nusselt number. Higher values of these physical quantities of interest are observed in the injection case than in the suction case. Meanwhile, the increase in the magnitude of the shrinking parameter improved and reduced the local skin friction coefficient and Nusselt number, respectively. Then, response surface methodology (RSM) is conducted to understand the interactive impacts of the controlling parameters in optimizing the physical quantities of interest. With a desirability of 66%, the local skin friction coefficient and Nusselt number are optimized at 1.528780016 and 0.888353037 when the shrinking parameter (λ) and mass transfer parameter (S) are −0.8 and −0.6, respectively.

This article analyses the processes of rural shrinking/revitalisation in Spain from the perspective of chain mobilities. It attempts to go beyond the vision that focuses on the depopulation approach. The chain migration perspective is a dynamic means, as it considers the articulation between internal/international, historical/recent migrations and shrinking/revitalisation processes. Spatial mobility is also analysed in relation to the articulation of the local and immigrant population's intergenerational social mobility processes. The research is based on intensive fieldwork (109 semi-structured interviews) conducted in several shrinking regions in Spain (Galicia, Andalusia and Castilla-La Mancha). Our research reveals how the internal and international exodus of the second half of the twentieth century in Spain, driven by the 'Developmentalist' economic model and implemented by Franco's regime, is the bases for the territorial imbalances and configuration of shrinking rural areas in this country. It also shows how de-agrarianisation and the lack of intergenerational replacement explains the arrival of immigrant populations in rural areas from the turn of the century onwards, in order to meet the needs of labour markets segmented by ethnic origin and gender. Together with newcomers, the shrinking areas are also benefiting from the arrival of returnees and root migrants (from both external and internal migration), who decide to return to their origins, drawn by emotional ties. These migration patterns (newcomers, returnees and root migrants) are different and complementary in terms of sustaining life in rural areas. The impact of migration on the revitalisation of rural areas is visible in demographic, economic and social terms. [ABSTRACT FROM AUTHOR]

Global climatic changes in recent decades cause changes in the dynamics of mountain geosystems. Of interest is the response of nival-glacial inland geosystems, which is different from those in the pre-Oceanic regions. In 2013, the authors substantiated the expediency of separating the nival-glacial mountain range geosystems within the Baikal Rift Zone and Mongolian Altai into a meridional research transect, within which it is possible to establish latitudinal patterns of modern intracontinental glacier functioning. Over the past decade of ongoing studies of glacial forms within the transect, many new data have been collected and analyzed. The present article based on systematic generalizations of these materials. The analysis of the state of mountain glaciation in the south of Eastern Siberia and Mongolia in the last decades has revealed a number of peculiarities. The deglaciation that began in the 1970s–1980s continues in all the mountain systems under consideration. It is a reaction to global climatic changes. The greatest reduction is experienced by the near-slope glaciers and flattop glaciers and to a lesser extent by the cirque ice glaciers. They have a significant volume loss due to thinning, while changes in the area of such glaciers are less significant. This is the main difference between the intracontinental glaciers and the preoceanic glaciers. In general, many nival-glacial geosystems of transitional forms are formed. Quantitative characteristics are based on the calculation of the volume of the East Sayan glaciers measured by geophysical radar. Thus, over 120 years, the Peretolchina (northern) Glacier has decreased in length by a factor of 1.75, in area by a factor of 2.9, and in volume by a factor of 3.71. During the same period, the area of the neighboring Radde Glacier decreased from 0.43 to 0.09 km2; its thickness by 30 m; and, accordingly, its volume by 3 times. The warming of air temperature for Western Mongolia is 0.03–0.29°C/10 years and, for the Baikal region, 0.2–0.5°C/10 years. Warming of air temperatures in the ridges of the Mongolian Altai is noted up to 48° N, and southward the trend is unstable. [ABSTRACT FROM AUTHOR]

Peculiarities of copolyimide modification by polyvinylpyrrolidone in a viscous state were studied. The differential scanning calometry revealed changes in the morphology and phase transitions of modified copolyamide materials. The increased technological compatibility between the components of copolyamide-polyvinyl pyrrolidone mixture was established. The effect of the modifier on the strength and thermophysical properties of the studied thermoplastic was found. Introduction of polyvinylpyrrolidone contributes to the growth of copolyamide strength under rupture and relative elongation and leads to a certain decrease in Vicat softening point and change of copolyamide technological properties. [ABSTRACT FROM AUTHOR]

Suburban revitalization efforts can remain ineffective when they do not adequately address the historic harm done to minority, low-income communities via economic, housing, public finance, banking, and urban planning practices. To determine an alternative approach, I use a process tracing method to study the efforts of a Midwestern inner-ring, minority-majority suburban community, returning from the edge of collapse after decades of disinvestment and crises. The findings reveal a significant change in revitalization efforts following the election of the first Black and first woman mayor; driven by justice-centered partnerships and justice-centered language. In my analysis, I argue that though the policy efforts do not vary significantly from standard redevelopment practices, the administration's emphasis on resolving historic harm added an important restorative justice lens, making the effort more fruitful and far-reaching. I conclude with recommendations to enhance the study and application of restorative justice themes in urban research. [ABSTRACT FROM AUTHOR]

Introduction: The pathology of a mucoid degeneration of the anterior cruciate ligament (MDACL) has been mentioned in several publications but due to its rare incidence it is not a well-known pathology. Partial or complete resection of the ACL is the option of choice after failed non-surgical treatment. However, the success rate of both surgical techniques and the subsequent risk of an ACL instability is not known. The purpose of this study was to compare the clinical and radiological outcome between partial resection and complete resection of the ACL in patients with MDACL. Materials and methods: Patients with MDACL verified by MRI and persistent knee pain were treated by partial (Group I) or complete resection (Group II) of the ACL and were included in a controlled clinical trial after unsuccessful conservative treatment for at least 6 months. Demographic, clinical and radiological data including the thickness of ACL, ACL/intercondylar ratio, patient's age at the time of surgery, the presenting symptoms, range of motion and ligament stability assessed by the ACL ligament score (Lachman test) were collected. In addition, Tegner activity score and Lysholm score were evaluated preoperatively and at final follow-up after a minimum of 12 months. Results: At final follow-up with a mean of 16.8 ± 8.8 months (range 12–41; Group I: 18.3 ± 9.7 vs. Group II: 15.3 ± 8.0; ns), all patients were pain free. Postoperatively, positive Lachman tests were noted in all patients (100%) in Group II (n = 5 patients with grade II and n = 5 patients with grade III). In Group I, 8 patients (80%) showed a negative Lachman test (grade I) and 2 patients (20%) a slightly elongated Lachman test with a firm stop (grade II). The mean knee flexion at follow-up examination was 132° ± 7° (range 120°–140°; Group I: 129° ± 9° vs. Group II: 135° ± 4°; ns). In pairwise comparison, flexion angle increased significantly in both groups (Group I: p = 0.0124 and Group II: p < 0.001). Pairwise comparison of thickness of the ACL and ACL/intercondylar ratio prior to and post-surgery in Group I showed non-significant differences. Conclusion: Both arthroscopic debridement and complete resection of the ACL lead to improvement of clinical and radiological findings in isolated MDACL. However, complete resection of the ACL will result in higher instability. Therefore, partial resection might be the better treatment option, especially in young patients with MDACL. [ABSTRACT FROM AUTHOR]

Polypropylene (PP), like all polymers, is susceptible to various forms of aging. Drawn fibers exhibit increased mechanical properties; however, the drawing results in non-equilibrium (decreased entropy) structures, due to the orientation of the polymer chains. Consequently, the drawn fibers are susceptible to an additional form of physical aging. In this work, the effect of common industrial additives on the mechanical strength of virgin and thermally aged PP fibers was studied. Thermogravimetry and tensile strength tests were used to characterize the drawn fibers, before and after physical thermal aging. PP drawn at 120 °C and at a drawing ratio of 7 exhibited a tensile strength of 549 MPa, while the incorporation of an antioxidant and a compatibilizer lowered the tensile strength down to 449 MPA. This reduction was related to the constraint of chain alignment due to the low molecular weight and poor dispersion of the additives. Depending on the aging temperature, shrinking occurred to different extents in pure PP fibers, accompanied by a 6–7% reduction in tensile strength. The fibers with incorporated additives exhibited higher rate and degree of shrinking. Briefly, the incorporation of such additives in drawn PP resulted in the deterioration of the fibers’ mechanical tensile properties. Since such additives have an indisputable value for non-drawn samples and their usage is necessary for various reasons also in drawn samples, e.g., for their protection from chemical aging/decomposition, additives specific for drawn samples should be developed.

The use of various types of rigid pavement is widespread because of its superiority in resisting heavy load vehicles. However, traffic loading complexity and subgrade response cause uncertainty during the design process. The presence of water in expansive soil issue swelling affected the flexural behavior of a rigid pavement slab. Rigid pavement relies heavily on the support and stability of the subgrade. Plain concrete is very weak in resisting tensile stresses so that the failure of rigid pavement slab structures often occurs in the expansive subgrade zone. Therefore, this study aims to numerically analyze the relationship between variations in the thickness of rigid pavement slabs on the flexural behavior parameters, such as critical and tensile stresses that affected water in expansive soil. The concrete's performance limit was determined, using its material's constitutive equation curve, and the data were analyzed using the finite element method. The results showed that the presence of water in expansive soil caused a change in soil volume (swelling), a reduction in soil bearing capacity (shrinking), and consequently, a rigid pavement cracked due to water variations in the subgrade. Generally, increasing the thickness of rigid pavement is a common method for mitigating the detrimental effects of expansive soil swelling. It is possible to provide reinforcement in other forms, which provide an opportunity to improve the performance of the concrete slab as a rigid pavement. For example, stabilization of expansive soil with materials capable of reducing its expansive power can be done but it requires large resources to realize it. Another method is to provide reinforcement to the rigid pavement slab structure, so that the rigid pavement slab is able to withstand traffic loads and also the expansion and shrinkage behavior of the expansive soil. [ABSTRACT FROM AUTHOR]

A digital twin describes the virtual representation of a real process. This twin is constantly updated with real data and can thus control and adapt the real model. Designing suitable digital twins for path planning of autonomous robots or drones is often challenging due to the large number of different dynamic environments and multi-task and agent systems. However, common path algorithms are often limited to two tasks and to finding shortest paths. In real applications, not only a short path but also the width of the passage with a path as centered as possible are crucial, since robotic systems are not ideal and require recalibration frequently. In this work, so-called homotopic shrinking is used to generate the digital twin, which can be used to extract all possible path proposals including their passage widths for 2D and 3D environments and multiple tasks and robots. The erosion of the environment is controlled by constraints such that the task stations, the robot or drone positions, and the topology of the environment are considered. Such a deterministic path algorithm can flexibly respond to changing environmental conditions and consider multiple tasks simultaneously for path generation. A distinctive feature of these paths is the central orientation to the non-passable areas, which can have significant benefits for worker and patient safety. The method is tested on 2D and 3D maps with different tasks, obstacles, and multiple robots. For example, the robust generation of the digital twin for a maze and also the dynamic adaptation in case of sudden changes in the environment is covered. This variety of use cases and the comparison with alternative methods result in significant advantages, such as high robustness, consideration of multiple targets, and high safety distances to obstacles and areas that cannot be traversed. Finally, it was shown that the environment for the digital twin can be reduced to reasonable paths by constrained shrinking, both for real 2D maps and for complex virtual 2D and 3D maps. [ABSTRACT FROM AUTHOR]

Background: Pelosols are the Soil of the Year 2022 in Germany, Austria and Switzerland. They represent soils with a high clay content (≥45%) in the diagnostic P horizon. Pelosols are nutrient‐rich, have a strong capacity for swelling and shrinking, have a challenging water balance with a high portion of nonplant available water and are affected by high traction. Such special characteristics make them challenging soils under agricultural management. Aims: The occurrence, land use management and soil erosion risk of Pelosols in Germany were investigated and compared to their clay‐rich soil counterparts on a global scale. Methods: We intersected soil maps of the German and international digital soil mapping with soil erosion data. Results: A high percentage (63%) of Pelosols in Germany are under agricultural use, from which two‐thirds are arable farming. Simultaneously, Pelosols have a high risk for soil erosion by water and are the fourth most endangered soil type compared to all soil types in Germany. The average soil erosion loss of Pelosols used for agricultural practices assessed by the Revised Universal Soil Loss Equation (RUSLE) is 2.24 t ha−1 year−1 compared to an average erosion loss of all agriculturally used soils in Germany of 1.65 t ha−1 year−1. From an international perspective, Pelosols in Germany are mostly mapped as haplic Cambisols or haplic Luvisols, as they do not necessarily meet the diagnostic properties of the clay‐rich Vertisol soil type. Most Vertisols are classified as Pelosols, but Pelosols do not necessarily fulfil the diagnostic criteria of Vertisols. Vertisols on a global scale have an even higher soil erosion risk than Pelosols in Germany (3.5 t ha−1 year−1). Conclusions: Pelosols and Vertisols, despite their high percentages for agricultural use, have a high soil erosion risk compared to other soil types and thus need special care under agricultural use and adapted protective land use management. [ABSTRACT FROM AUTHOR]

In this paper, we survey the volume growth estimates for shrinking, steady, and expanding gradient Ricci solitons. Together with the known results, we also prove some new volume growth estimates for expanding gradient Ricci solitons. [ABSTRACT FROM AUTHOR]

The soil shrink–swell phenomenon produces crack networks and slope instability. However, few studies have involved the continuous shrink–swell process of granite residual soils. The objective of the study is to explore the shrink–swell process of weathered granite soils and its effects on gully development in southern China. The bulk density, soil water content (SWC), shrink–swell ratio (SSR), clay mineral content, and mechanical composition, etc., of soil samples from five soil layers (at depths of 0.3 m, 3.0 m, 7.0 m, 12.0 m, and 16.0 m) along a profile in Yudu County was analyzed. After quantifying the soil properties at different soil depths, we analyzed these data statistically in an effort to identify strong parametric relationships. The results indicated that some properties such as bulk density and shear stress increased with soil depth, while other soil properties, such as plasticity index and liquid limit, were inversely related to depth. Soil cohesion, the angle of internal friction, and shear stress were closely related to the SWC. Every 1% decrease in the SWC resulted in a shear stress reduction of 6.62 kPa. The SSR values exhibited significant variation between the three dry–wet cycles and were closely related to the bulk density values of our kaolin and montmorillonite samples. As an environmental factor, the SWC can trigger changes in internal soil properties such as shear stress and the SSR. Using these data and observations made during our field survey, it can be proposed that continuous shrink–swell variation in deep granite-weathering crust can result in crack formation and gully erosion. It can be inferred that crack development velocity and gully retreat rate may be affected by the soil's shrink–swell process. Consequently, this information provides insight to understanding the mechanism of gully development in southern China. [ABSTRACT FROM AUTHOR]

Abstract A microdevice that offers glucagon supplements in a safe, non‐invasive, and glucose‐responsive manner is ideal for avoiding fatal hypoglycemia consequences from insulin overdosage during daily diabetes treatment. However, mold‐assisted microfabrication of biomedical materials or devices typically needs high‐resolution laser ablation to scale down structural design. In addition, the majority of the polymeric drug delivery materials being used to fabricate devices are dissolvable or deformable in aqueous environments, which restricts washing‐based cleaning and purification procedures post shape fixation. This study leverages the design flexibility of 3D printing‐assisted mold casting and presents a shrinking microfabrication approach that allows subsequent washing procedures to remove toxic monomer residues during polymerization. The feasibility of this approach is demonstrated by developing a glucose‐responsive transdermal glucagon microneedle patch through matrix volume change‐mediated release kinetic control. Shown in the type 1 diabetic mouse model, this transdermal patch can reverse the occurrence of hypoglycemia while lowering the risk of monomer residue‐induced irritation during treatment. Freeing from the restrain of molding resolution for microstructure design, this shrinking methodology further provides an insight into post‐fabrication purifications of biomedical materials.

Conventional liquids have poor thermal conductivity, thus limiting their use in engineering. Therefore, scientists and researchers have created nanofluids, which consist of nanoparticles dispersed in a base fluid, to improve heat transfer properties in various fields, such as electronics, medicine, and molten metals. In this study, we examine the micropolar nanofluid flow in a stagnation region of a stretching/shrinking sheet by employing the modified Buongiorno nanofluid model. The nanofluid consists of magnetite (Fe3O4) nanoparticles. The similarity equations are solved numerically using MATLAB software. The solution is unique for the shrinking strength λ ≥ − 1 . Two solutions are found for the limited range of λ when λ c < λ < − 1 . The solutions terminate at λ = λ c in the shrinking region. The rise in micropolar parameter K contributes to the increment in the skin friction coefficient Re x 1 / 2 C f and the couple stress Re x M w , but the Nusselt number Re x − 1 / 2 N u x and the Sherwood number Re x − 1 / 2 S h x decrease. These physical quantities intensify with the rise in the magnetic parameter M. Finally, we investigated the stability of the solutions over time. This work contributes to the dual solution and time stability analysis of the current problem. In addition, critical values of the main physical parameters are also presented. These critical values are usually known as the separation values from laminar to turbulent boundary layer flows. In this case, once the critical value is achieved, the process for the specific product can be planned according to the desired output to optimize the productivity. [ABSTRACT FROM AUTHOR]

Depopulation and shrinkage are a common socio-spatial phenomenon in many Northern localities and are frequently accompanied by a stigmatization of the affected localities and their populations. This editorial introduces the special issue on depopulation and shrinkage in a Northern context that takes its point of departure from the Nordic Geographers Meeting 2022 on multiple geographies and its keynote lecture by Josefina Syssner on the question: What can geographers do for shrinking geographies? The special issue displays a range of contributions from Northern context that discuss and evaluate the heterogenous processes of shrinking localities from multiple perspectives within and beyond geography. Through broad, yet empirically detailed and multiscalar focused assessments it stresses that shrinkage as a phenomenon is a fundamental character of Nordic and other societies, which requires a rethinking and should be acknowledged as a 'natural' development trajectory in planning and development. [ABSTRACT FROM AUTHOR]

Fifty years of continuous monitoring of the bank vole population (Myodes glareolus Schreber, 1780) revealed the phenomenon of shrinking body size of individuals, manifesting in significant reduction in their regular size and mass parameters. Field observations were carried out in the Kaniv Nature Reserve (Cherkasy region, Ukraine) during the first half of summer every year. In the forest biotopes of the reserve, this species is dominant in the group of rodents. The research period covered various stages of the existence of the protected ecosystem. Its small area, location ina densely populated region of Ukraine and interaction with neighboring territories which are involved in economic activities have always caused anthropogenic pressure on the protected area. Its nature and intensity determined the changes in the protection regime and the loss of reserve status in 1951–1968. Later, the territory of the reserve experienced increasing technogenic pressure accompanied by radioactive contamination. In this work, to compare their characteristics, four complete cycles of the density dynamics of the bank vole population (from depression to depression) were selected, the duration of which was 4–5 years. The first three cycles correspond to qualitatively different periods in the existence of the ecosystem and the population of the studied species, and the last one corresponds to the relatively current situation. Over the recent 30 years, the size and mass parameters of individuals of bank voles have deсreased, - this phenomenon was called shrinking. The process was also observed to tend towards consistent increase in scale. Differentiated analysis shows that in different sex and functional groups of animals, the decrease in exterior parameters can reach 30.3%. Shrinking is especially notable in the group of adult females that are actively involved in reproduction (compared to the second cycle, considered as the control, the decrease in parameters among these is 33.2%). Juveniles of this sex lost 31.8% of their fatness. Besides, in the population of voles, the proportion of large-size individuals was significantly reduced. The group of animals that overwintered significantly reduced its representation, and its existing representatives had much smaller exterior parameters. The studies found that the shrinking process is stable over time, which does not allow it to be considered a random phenomenon or an artifact of research. This phenomenon has no correlation with the amount or availability of food. It occurs against the background of numerous changes in various aspects of population dynamics, which gives grounds to associate it with anthropogenic changes in the environment. Shrinking is believed to be realized through various mechanisms. Firstly, as a result of mortality, the largest individuals and reproducing females with the greatest energy needs disappear from the population, and secondly, the growth and weight gain of young animals is slower. As a result, decrease in the size and mass parameters of individuals reduces their specific energy needs and allows the population to bring their requirements in correspondance with the capability of the environment to support a certain number of resource consumers. An analogy was drawn with the Dehnel’s phenomenon, described for shrews of the Sorex genus, whose body size and weight decrease is an element of preparation for experiencing adverse winter conditions. Based on similar concepts, the shrinking of its elements can be considered as a specific population strategy to maintain the ecological balance.

The transformation of thermoplastic polyurethanes into polymeric foams is attracting great interest nowadays. However, this technology has some challenges that it is necessary to resolve, being one of the most important the shrinkage suffered by the polymeric foams over time. For that reason, this work explores several alternatives to mitigate this phenomenon. These alternatives are divided into two groups: on the one hand, the refoaming of the shrunken foams using supercritical CO 2 and N 2 was explored; on the other hand, the foaming using mixtures of supercritical CO 2 and N 2 as foaming agents was carried out. After experiments, it was seen that, the refoaming with N 2 of shrunken foams obtained by supercritical CO 2 technology can increase and keep constant the initial expansion ratio of the shrunken foams. Moreover, it was also observed that ratios of CO 2 /N 2 between 80/20 and 60/40 can avoid the shrinking issues suffered by the polymeric foams after foaming using supercritical technology. [Display omitted] • N 2 refoaming of shrunken foams can slightly increase and keep constant the initial expansion ratio of the shrunken foams. • Ratios of CO 2 /N 2 between 80/20 and 60/40 can avoid the shrinking issues suffered by the polymeric foams after foaming. • Using supercritical CO 2 as refoaming agent it was possible to duplicate the initial expansion ratio of the foams obtained. • The starter morphology of the foams obtained can be slightly modified by the refoaming pressure. [ABSTRACT FROM AUTHOR]

• The flow and heat transfer of hybrid nanofluid is solved numerically. • Dual solutions are presented and only one solution is stable. • The heat transfer is improvable by maximizing the velocity slip and Soret parameters. • The fluid with concentrated copper could prevent the flow separation process. This study investigates the unsteady axisymmetric flow of a hybrid graphene-copper nanofluid over a permeable radially shrinking disk, accounting for velocity slip, Dufour, and Soret effects. Examining such boundary layer flows of hybrid nanofluids is crucial for understanding the underlying fluid mechanics and thermophysical behavior. The fluid flow model is solved using a finite difference scheme in MATLAB to generate the numerical solutions. Since dual solutions are attainable, stability analysis is performed to analyze the nature of the solutions. The existence of dual solutions enables exploring flow separation dynamics through selected control parameters. Results indicate that higher copper volume fraction and velocity slip effectively prevent the boundary layer separation. The 2 % copper volume fraction delays the boundary layer separation approximately 6 % better compared to the usage of 1 % copper volume fraction. The heat transfer is improvable by reducing the shrinking intensity of the disk and maximizing the velocity slip and Soret parameters. The comprehensive mathematical model presented herein lay a solid foundation for future research endeavors, particularly in the field of hybrid nanofluids and their applications in thermal management systems. [ABSTRACT FROM AUTHOR]

Structural changes during the drawing and shrinking of linear low-density polyethylene (LLDPE) film are analyzed through in-situ X-ray measurements. A synchrotron radiation source enables simultaneous analyses combining small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD). During drawing, the original unoriented SAXS and WAXD patterns transformed into line and spot patterns, indicating the orientation of both lamellar stacking and the molecular axis along the drawing direction. During the subsequent shrinking these patterns are retained, suggesting the tilted lamellar and molecular chains. A possible model for structural changes indicates that tie molecules between lamellae effectively transmit drawing and shrinking stresses, which contributes to desirable actuation properties. [ABSTRACT FROM AUTHOR]

This study aims to investigate the relief effects on woven fabrics by using heat-sensitive thermoplastic-shrink yarns and different yarn types together. The purpose of examining the relief effects is to create innovative surfaces and increase aesthetic value in the design of woven fabrics with yarns that gain permanent shape by shrinking with heat treatments. In line with the purpose, first of all, thermoplastic yarns and the studies carried out in this context, the fabrics produced were examined. The information gained was evaluated within the scope of woven fabric design, and relief effect woven fabrics were designed within the scope of a theme. Before the production process of the main fabric designs, preliminary research fabrics were woven for the selection of the appropriate yarn type, weaving structure, and knitting that will create the relief effects in the designs in the most accurate way. With the data obtained from the preliminary research, yarn, woven, and woven fabric structures were determined for fabrics and main designs and production calculations were made. After weaving production, all fabrics were heat-treated to create permanent relief effects after being removed from the loom. The relief effects seen in all fabrics after heat treatment were evaluated in terms of both structural and theme-related appearance by relating the type of yarn used in the production of fabrics, weaving, and woven structure. Evaluations were also made according to the numerical and visual data determined during the design and production process. The preliminary research results and the descriptions of the main fabrics are discussed under the relevant sections, and their contributions to the design and production process are stated in the conclusion section. In the production process of the fabrics, dobby weaving techniques were used in the preliminary research fabrics, and jacquard weaving techniques were used in the production of the main fabrics. Single-layer, self-connecting double-layer, and double-layer bag structures were used as woven fabric structures. The yarns used are thermoplastic yarns that are heat sensitive and cotton and polyester yarns that do not heat sensitive. In the design and application works considered as interior textiles; in addition to thermoplastic yarns, the effects of non-thermoplastic yarns in terms of relief were also observed in terms of aesthetic quality and structure. In addition to the use of thermoplastic yarns with non-thermoplastic yarns, the desired aesthetic relief effects have been achieved with the combination of weaving structures, weave, and yarn density selected depending on the designs revealed in line with the themes of the fabrics. It is thought that the study will contribute to the development of innovative perspectives in terms of function and aesthetics in creating relief effects in woven fabric design with the use of thermoplastic and non-thermoplastic materials, and weaving techniques. [ABSTRACT FROM AUTHOR]

Decomposing a complex object into simple components is a fundamental problem in geometry processing. Existing methods for decomposing point clouds rely on local or global features of an object, which leads to over-segmentation or unnatural component boundaries. In this paper, we propose a novel method for decomposing the point cloud by using internal and external critical points. First, we propose a novel shrinking strategy to build the global skeleton topology, from which we can extract internal critical points for locating components. External critical points are selected from the ridge and valley points for component segmentation. Then, we apply the constraint of internal and external critical points to decompose an object into semantic components by skeleton-based piecewise labeling. Experimental results demonstrate that our method is effective in decomposing 3D point clouds and is robust to limited noise and incomplete data. [Display omitted] • A shrinking-based skeleton extraction method is proposed to reserve sharp features. • A point cloud decomposition based on global and local features is presented. • Our framework has good efficiency and robustness in point cloud decomposition. [ABSTRACT FROM AUTHOR]

Age-related declines in physical function, body composition, and cognitive function are interrelated. This prospective study aimed to examine the impact of mild cognitive impairment (MCI) on age-related changes in physical function and body composition among community-dwelling older adults. We analyzed data from 180 older adults (aged ≥70 years) who completed a longitudinal assessment of physical function and body composition in the community. Physical function included grip strength and time taken to walk 10 m at normal and maximum pace. Body composition assessments calculated the body mass index (BMI) and appendicular skeletal muscle index (ASMI) using bioelectrical impedance analysis at baseline and three-year follow-up assessments. MCI was defined as values below the age- and education-adjusted reference threshold in several tests, including memory, attention, executive function, and processing speed. Participants were divided into the MCI and non-MCI groups based on their MCI status at baseline. A two-way repeated-measures analysis of covariance (ANCOVA), adjusting for age and gender, was used to analyze the group (MCI and non-MCI) by time (baseline and three-year follow-up) interaction. Thirty participants (16.7%) had MCI at baseline. The repeated-measures ANCOVA indicated that no variables had significant group by time interactions. Stratified analyses by gender (repeated-measures ANCOVA, adjusted for age) confirmed a significant group by time interaction on BMI (F=5.63, p=0.02) and ASMI (F=6.33, p=0.01) among women. Older women with MCI may experience a greater impact of the acceleration of shrinking and age-related decline in muscle mass. The close associations of MCI with shrinking and muscle mass loss have important implications for targeting interventions among MCI women., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Ethics Committee on Epidemiological and Its Related Studies of Kagoshima University, Sakuragaoka Campus issued approval 170351. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: This work was supported by the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for Scientific Research (B) Grant Number 19H03978. The sponsor's source had no role in the study design, data collection, data analysis, data interpretation, or report writing. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Makizako et al.)

In this paper, we extend techniques developed in the context of the Travelling Salesperson Problem for cycle problems. Particularly, we study the shrinking of support graphs and the exact algorithms for subcycle elimination separation problems. The efficient application of the considered techniques has proved to be essential in the Travelling Salesperson Problem when solving large size problems by Branch-and-Cut, and this has been the motivation behind this work. Regarding the shrinking of support graphs, we prove the validity of the Padberg–Rinaldi general shrinking rules and the Crowder–Padberg subcycle-safe shrinking rules. Concerning the subcycle separation problems, we extend two exact separation algorithms, the Dynamic Hong and the Extended Padberg–Grötschel algorithms, which are shown to be superior to the ones used so far in the literature of cycle problems. The proposed techniques are empirically tested in 24 subcycle elimination problem instances generated by solving the Orienteering Problem (involving up to 15,112 vertices) with Branch-and-Cut. The experiments suggest the relevance of the proposed techniques for cycle problems. The obtained average speedup for the subcycle separation problems in the Orienteering Problem when the proposed techniques are used together is around 50 times in medium-sized instances and around 250 times in large-sized instances. [ABSTRACT FROM AUTHOR]

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Polycarbophil (POL), a polyacrylic acid cross-linked with divinyl glycol, is widely used in semisolid and solid dosage forms. When undergoing a thermal treatment in the range 120–160 °C, POL shows interesting morphological modifications, related to changes in physical properties, such as swelling of the powder granules, or hardening and matrix formation if included in the composition of a tablet. Thermal analysis conducted on POL highlighted a thermal event (Z) that can be correlated both to the shrinking of the powder granules and to the matrix formation in compacted POL powder. Modulated differential scanning calorimetry (MDSC) allowed to distinguish, inside event Z, an irreversible process overlapping with a reversible glass transition, attributable to the volatilization of residual solvents identified, through a complex TGA-FTIR-GC–MS interface, as acetate esters used for the polymer production as very fine powder. A specific interaction between acetates and POL, capable of stabilizing the polymer chains in a given conformation, was highlighted. The molecular rearrangement of the POL chains, following the volatilization of the solvent-stabilizers, is therefore ascribable to a loss of energetic stability of this material, which justifies the shrinking phenomena in the granules of the powder and the matrix formation when POL is compacted.

A digital twin describes the virtual representation of a real process. This twin is constantly updated with real data and can thus control and adapt the real model. Designing suitable digital twins for path planning of autonomous robots or drones is often challenging due to the large number of different dynamic environments and multi-task and agent systems. However, common path algorithms are often limited to two tasks and to finding shortest paths. In real applications, not only a short path but also the width of the passage with a path as centered as possible are crucial, since robotic systems are not ideal and require recalibration frequently. In this work, so-called homotopic shrinking is used to generate the digital twin, which can be used to extract all possible path proposals including their passage widths for 2D and 3D environments and multiple tasks and robots. The erosion of the environment is controlled by constraints such that the task stations, the robot or drone positions, and the topology of the environment are considered. Such a deterministic path algorithm can flexibly respond to changing environmental conditions and consider multiple tasks simultaneously for path generation. A distinctive feature of these paths is the central orientation to the non-passable areas, which can have significant benefits for worker and patient safety. The method is tested on 2D and 3D maps with different tasks, obstacles, and multiple robots. For example, the robust generation of the digital twin for a maze and also the dynamic adaptation in case of sudden changes in the environment is covered. This variety of use cases and the comparison with alternative methods result in significant advantages, such as high robustness, consideration of multiple targets, and high safety distances to obstacles and areas that cannot be traversed. Finally, it was shown that the environment for the digital twin can be reduced to reasonable paths by constrained shrinking, both for real 2D maps and for complex virtual 2D and 3D maps.

The soil shrink–swell phenomenon produces crack networks and slope instability. However, few studies have involved the continuous shrink–swell process of granite residual soils. The objective of the study is to explore the shrink–swell process of weathered granite soils and its effects on gully development in southern China. The bulk density, soil water content (SWC), shrink–swell ratio (SSR), clay mineral content, and mechanical composition, etc., of soil samples from five soil layers (at depths of 0.3 m, 3.0 m, 7.0 m, 12.0 m, and 16.0 m) along a profile in Yudu County was analyzed. After quantifying the soil properties at different soil depths, we analyzed these data statistically in an effort to identify strong parametric relationships. The results indicated that some properties such as bulk density and shear stress increased with soil depth, while other soil properties, such as plasticity index and liquid limit, were inversely related to depth. Soil cohesion, the angle of internal friction, and shear stress were closely related to the SWC. Every 1% decrease in the SWC resulted in a shear stress reduction of 6.62 kPa. The SSR values exhibited significant variation between the three dry–wet cycles and were closely related to the bulk density values of our kaolin and montmorillonite samples. As an environmental factor, the SWC can trigger changes in internal soil properties such as shear stress and the SSR. Using these data and observations made during our field survey, it can be proposed that continuous shrink–swell variation in deep granite-weathering crust can result in crack formation and gully erosion. It can be inferred that crack development velocity and gully retreat rate may be affected by the soil’s shrink–swell process. Consequently, this information provides insight to understanding the mechanism of gully development in southern China.

Bamboo is structural gradient materials with hygroscopic properties. Understanding the variations in hygro-deformation behavior across the radial direction is crucial for managing the dimensional stability of bamboo. Herein, high-resolution microscopy and the digital image correlation (DIC) technique were combined to analyze the transverse shrinking and swelling of bamboo. Parenchyma cells were utilized as natural "tracking points" for DIC analysis to evaluate full-field strain at different radial positions, specifically the outer, middle and inner regions. The transverse shrinking and swelling of bamboo were found to exhibit a quasi-linear distribution in the tangential direction and a saddle-like distribution in the radial direction. The outer region, which had a higher fiber fraction, displayed greater and more isotropic hygro-deformation compared to the inner regions with fewer fibers. When relative humidity (RH) increased from 0% to 97%, the swelling ratio in the radial direction was 2.00, 1.55 and 1.22% for the outer, middle and inner regions, respectively. In the tangential direction, the swelling ratio was 1.75, 1.35 and 1.10%. The study also highlighted the differences in hygro-deformation between the fiber and parenchyma cells, with the fiber experiencing both greater shrinking and swelling compared to the parenchyma. Furthermore, the interactions between the fibers and parenchyma varied across different radial regions. Overall, this study demonstrated the use of individual bamboo cells as natural tracking points in DIC analysis and contributed to a better understanding of the relationships between bamboo and water, as well as the radial variation in shrinking and swelling of bamboo. • Parenchyma cells were utilized as natural "tracking points" in DIC analysis. • Variations of shrinking and swelling across the radial direction of bamboo were evaluated. • Quasi-linear and saddle-like distributions of hygro-deformation were found in the T and R direction, respectively. [ABSTRACT FROM AUTHOR]

This is a commentary to the Fennia lecture and article "What could geographers do for shrinking geographies?" by Josefina Syssner. In the piece I open up questions concerning shrinking from a global perspective and point to further discussions on global east, south, and spatial justice in post-fossil transition, which I encourage the Nordic research to engage with in the future. [ABSTRACT FROM AUTHOR]

In this paper we study the nature of Ricci solitons in D-homo-thetically deformed Kenmotsu manifolds. We prove that η -Einstein Kenmotsu metric as a Ricci soliton remains η -Einstein under D-homothetic deformation and the scalar curvature remains constant.

Conventional liquids have poor thermal conductivity, thus limiting their use in engineering. Therefore, scientists and researchers have created nanofluids, which consist of nanoparticles dispersed in a base fluid, to improve heat transfer properties in various fields, such as electronics, medicine, and molten metals. In this study, we examine the micropolar nanofluid flow in a stagnation region of a stretching/shrinking sheet by employing the modified Buongiorno nanofluid model. The nanofluid consists of magnetite (Fe3O4) nanoparticles. The similarity equations are solved numerically using MATLAB software. The solution is unique for the shrinking strength λ≥−1. Two solutions are found for the limited range of λ when λc<λ<−1. The solutions terminate at λ=λc in the shrinking region. The rise in micropolar parameter K contributes to the increment in the skin friction coefficient Rex1/2Cf and the couple stress RexMw, but the Nusselt number Rex−1/2Nux and the Sherwood number Rex−1/2Shx decrease. These physical quantities intensify with the rise in the magnetic parameter M. Finally, we investigated the stability of the solutions over time. This work contributes to the dual solution and time stability analysis of the current problem. In addition, critical values of the main physical parameters are also presented. These critical values are usually known as the separation values from laminar to turbulent boundary layer flows. In this case, once the critical value is achieved, the process for the specific product can be planned according to the desired output to optimize the productivity.