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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]

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]

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]

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]

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]

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. [ABSTRACT FROM AUTHOR]

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]

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]

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]

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]

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]

Assuming a life cycle perspective and using the link between demography and house prices, this article proposes a new approach to analyze the spatial reshaping of housing wealth caused by the elder boom. The modification in housing wealth circulation across generations is also a spatial modification that carries consequences for local territories. Applied to the French case at the departmental level, this methodology is also relevant for European countries confronted to an aging shock. We find that although the losses are amplified for some departments, others benefit from this aging shock. Metropolization is insurance against important housing wealth losses, whereas for the nonmetropolitan departments, a combination of second-order factors is required to avoid wealth decline. Our results suggest that these evolutions are mainly structural and that the cyclical variables are of secondary importance. Compensation, by positive cyclical trend, for structural decline is not a circumstance that currently occurs in the French case. Social classes also appear to be strongly related to this change, in which various spatial inequalities are reinforced. As for the unemployment rate, this indicator poorly reflects the shift and may be misleading for a regional planning policy. [ABSTRACT FROM AUTHOR]

For a variety of applications of microbubbles, it is necessary to clarify the dissolution dynamics and the lifetime of a microbubble. Although various models have been proposed, predicting the dissolution rate of a microbubble in a static fluid with a surfactant is still difficult. In this study, dissolution behavior was predicted with taking into account the mass transfer inhibition effect due to a surfactant at the bubble surface. The shrinking behavior of an oxygen microbubble was observed with several surfactants and the experimental results were in good agreement with model predictions. [ABSTRACT FROM AUTHOR]

Introduction: In Africa and other Low Resource Settings (LRS), the guideline-based and thus in most cases mesh-based treatment of inguinal hernias is only feasible to a very limited extent. This has led to an increased use of low cost meshes (LCMs, mostly mosquito meshes) for patients in LRS. Most of the LCMs used are made of polyethylene or polyester, which must be sterilized before use. The aim of our investigations was to determine changes in the biocompatibility of fibroblasts as well as mechanical and chemical properties of LCMs after steam sterilization. Material and methods: Two large-pored LCMs made of polyester and polyethylene in a size of 11 x 6 cm were cut and steam sterilized at 100, 121 and 134 °C. These probes and non-sterile meshes were then subjected to mechanical tensile tests in vertical and horizontal tension, chemical analyses and biocompatibility tests with human fibroblasts. All meshes were examined by stereomicroscopy, scanning electron microscopy (SEM), LDH (cytotoxicity) measurement, viability testing, pH, lactate and glycolysis determination. Results: Even macroscopically, polyethylene LCMs showed massive shrinkage after steam sterilization, especially at 121 and 134 °C. While polyester meshes showed no significant changes after sterilization with regard to deformation and damage as well as tensile force and stiffness, only the unsterile polyethylene mesh and the mesh sterilized at 100 °C could be tested mechanically due to the shrinkage of the other specimen. For these meshes the tensile forces were about four times higher than for polyester LCMs. Chemical analysis showed that the typical melting point of polyester LCMs was between 254 and 269 °C. Contrary to the specifications, the polyethylene LCM did not consist of low-density polyethylene, but rather high-density polyethylene and therefore had a melting point of 137 °C, so that the marked shrinkage described above occurred. Stereomicroscopy confirmed the shrinkage of polyethylene LCMs already after sterilization at 100 °C in contrast to polyester LCMs. Surprisingly, cytotoxicity (LDH measurement) was lowest for both non-sterile LCMs, while polyethylene LCMs sterilized at 100 and 121 °C in particular showed a significant increase in cytotoxicity 48 hours after incubation with fibroblasts. Glucose metabolism showed no significant changes between sterile and non-sterile polyethylene and polyester LCMs. Conclusion: The process of steam sterilization significantly alters mechanical and structural properties of synthetic hernia mesh implants. Our findings do not support a use of low-cost meshes because of their unpredictable properties after steam sterilization. [ABSTRACT FROM AUTHOR]

After the financial crisis of 2008, a time of reputation rebuilding began in Iceland. Women had been absent in the process leading up to the crisis and a strong discourse emerged calling for women to restore the country and blaming the crisis on the male 'business Vikings". At the same time, Iceland became a frontrunner in the Global Gender Gap Report. This article draws on scholarship on the discursive construction of gender equality, nation branding and gender measurements. Taking Iceland as a case example, the article critically examines gender indices with a special focus on the Global Gender Gap index. It explores how a narrow understanding of gender equality is evident in the composition of the Global Gender Gap measurement, illustrating the "shrinking" and "bending" of the concept. The article shows the process in which gender equality rankings are employed in the politics of reputation and turned into nation branding. The article adds to the knowledge of how measurements and indices contribute to the emergent emphasis on gender equality in nation branding. [ABSTRACT FROM AUTHOR]

The rising prevalence of non-communicable diseases (NCDs) has led to increased attention on understanding how built environments affect NCD risks. However, there's a significant gap in the literature regarding the relationship between housing vacancy duration and NCDs in metropolitan areas with varying development rates. Our research addresses this gap by examining the association between housing vacancy duration and NCDs across all U.S. metropolitan areas, considering growing, shrinking, and fluctuating counties. We used a Multiscale Geographically Weighted Regression (MGWR) model to analyze this relationship, finding that longer-term vacant housing (over 3 years) is more positively associated with NCDs compared to short-term vacancies. We also discovered that this association is non-uniform across metropolitan counties, except for cancer and stroke outcomes. Shrinking counties in the Northeast are particularly affected, emphasizing the need for targeted public health interventions in these areas. This study underscores the importance of revitalizing vacant homes, especially those vacant for over 3 years, in both shrinking and growing regions to improve public health. Policymakers should adopt tailored strategies, engage public health experts, and invest in healthcare infrastructure to effectively address the health risks linked to vacant housing. • From 2014 to 2019, vacant housing increased in all metro counties of the U.S. • Shrinking counties had high vacant rates, while growing ones saw the biggest rise. • Short-term vacancy linked to fewer NCDs, while longer-term vacancy tied to most. • The relationships between longer-term vacant housing and NCDs are not stationary. [ABSTRACT FROM AUTHOR]

The volumetric response upon drying is relevant in the geotechnical and ceramic industry due to the key role played in crack formation. The volumetric response of clays upon drying is relatively complex; the void ratio decreases considerably in the saturated state, levels off almost abruptly at the onset of desaturation, and increases at very low water contents. This paper presents an original deformable pore-network model (DPNM) to elucidate the micromechanisms controlling the complex volumetric response of clays upon drying. The main features of the DPNM are the 'binary' approach (pores in the clay are assumed to be either fully saturated with water or dry) and the use of independent tests to calibrate the parameters of the model (compression behaviour of saturated reconstituted clay and dry powder). The DPNM shows that all pores shrink as pore-water tension increases in the saturated state, although the larger pores contribute more to the overall reduction in void ratio. At the onset of desaturation, the larger pores dry out and rebound, whereas the smaller pores remain saturated and shrink. At very low water content/high pore-water tension, the desaturation of the smaller pores causes them to rebound, thus generating a macroscopic increase in the void ratio. [ABSTRACT FROM AUTHOR]

Aim: The present cross‐sectional study examined the associations of social frailty status with loss of muscle mass and weakness among community‐dwelling older adults. Methods: Data from 353 older adults (74.8% women) who had participated in a community‐based health check survey (Tarumizu Study) were analyzed. Social frailty was defined using responses to five questions (going out less frequently, rarely visiting friends, feeling unhelpful to friends or family, living alone and not talking with someone every day). Participants with two or more components were considered socially frail. We assessed appendicular skeletal muscle mass using bioelectrical impedance analysis and calculated appendicular skeletal muscle index. Dominant handgrip strength was assessed. Loss of skeletal muscle mass (appendicular skeletal muscle index <7.0 kg/m2 for men, <5.7 kg/m2 for women) and muscle weakness (handgrip strength <26 kg for men, <18 kg for women) were determined based on the Asian Working Group for Sarcopenia criteria. Results: The prevalence of social frailty was 14.7%. A higher prevalence of muscle weakness and loss of skeletal muscle mass in participants with social frailty was shown than in those without (muscle weakness 44.2% vs 23.6%, P ≤ 0.05; loss of skeletal muscle mass 59.6% vs 46.2%, P = 0.07). Social frailty was independently associated with muscle weakness (odds ratio 2.04, 95% confidence interval 1.06–3.95), but not with loss of skeletal muscle mass (odds ratio 1.47, 95% confidence interval 0.78–2.76) after adjusting for covariates. Conclusions: Social frailty status could be associated with muscle weakness, though not a loss of skeletal muscle mass. Geriatr Gerontol Int 2019; 19: 76–80. [ABSTRACT FROM AUTHOR]

The objective of the present paper is to study the Kenmotsu manifold admitting the Schouten-van Kampen connection. We study the Kenmotsu manifold admitting the Schouten-van Kampen connection satisfying certain curvature conditions. Also, we prove the equivalent conditions for the Ricci soliton in a Kenmotsu manifold to be steady with respect to the Schouten-van Kampen connection. [ABSTRACT FROM AUTHOR]

Stable and durable wood products can be produced by chemical modification at the molecular level. One modification that is effective in achieving these properties is by reacting both hardwoods and softwoods with acetic anhydride. The reaction takes place in the most accessible hydroxyl groups in the cell wall polymers. Lignin reacts the fastest followed by the hemicelluloses. Both are highly substituted. As the level of bonded acetyl increases, dimensional stability increases and attack by fungi decreases. The threshold of fungal resistance is approximately 18% acetyl. The moisture in the cell wall may be too low to support fungal growth. This is a summary of several independent projects on the mechanism of property enhancement that were previously published in proceedings. [ABSTRACT FROM AUTHOR]

In the Independent Set of Convex Polygons problem we are given a set of weighted convex polygons in the plane and we want to compute a maximum weight subset of non-overlapping polygons. This is a very natural and well-studied problem with applications in many different areas. Unfortunately, there is a very large gap between the known upper and lower bounds for this problem. The best polynomial time algorithm we know has an approximation ratio of nϵ and the best known lower bound shows only strong NP-hardness. In this paper we close this gap, assuming that we are allowed to shrink the polygons a little bit, by a factor 1-δ for an arbitrarily small constant δ>0, while the compared optimal solution cannot do this (resource augmentation). In this setting, we improve the approximation ratio of nϵ to (1+ϵ) which matches the above lower bound that still holds if we can shrink the polygons. [ABSTRACT FROM AUTHOR]

The rapid shrinking of Hungarian small towns became such a general process after the turn of the Millennium, which does not simply reflect the overall effects of the second demographic transition, and could not even be interpreted with local and regional factors. The aim of the present paper is to analyse the shrinking of small towns among the framework of post-socialists urban transformation models and concepts. Many authors have dealt with such transformation issues, but rather focusing on the description of the development of larger cities and analysing the transformation of urban space and society. Despite the evident differences caused by the size of the researched settlements (small urban centres with a maximal population of 30,000 people), some general elements of these concepts give parts of the explanations we looked for. Others are rooted much deeper: our paper finally states that the present day crisis of small towns originates back to the later decades of planned economy, when the forced and somewhat over-dimensioned modernisation of small towns resulted a significant role in the urban network. This modernisation was centrally planned, led and financed, and with the exhaustion of these exogenous sources small towns seem to return to a less intensive development path. [ABSTRACT FROM AUTHOR]

Light is being widely used in biomedicine due to its non-invasive nature, with application in imaging techniques and as a therapeutic agent. However, several aspects of its effect on irradiated tissues still leads to discussion in the scientific community. This particularly relates to novel biological models, as is the case of 3D multicellular spheroids, which are rising as an intermediate model between in vitro monolayer cultures and small animals. The applications of these spherical cell aggregates are diverse and include tissue reconstruction, drug testing or cancer studies, to cite some. To address the effect of light on these models, we use spheroids formed by MCF-7 (adenocarcinoma) or by U-87 MG (glioblastoma) cells. After their growth, they have been irradiated individually with focused laser radiation in the near-infrared (808 nm and 1450 nm), which provokes size changes in the spheroid. Time-lapse imaging in a brightfield microscope allows to define a reduction parameter, which informs about the extent of the size change. This parameter is correlated with cell viability studies; thus, we can set a safe range of reduction in which spheroids are not damaged by irradiation, and a threshold that should be avoided to keep cell mortality low. This correlation can be used as preliminary and visual information on the survival of cells during optical experiments with 3D spheroids. • Damaging irradiation doses in the near-infrared depend on the exact laser wavelength. • The size of single multicellular spheroids visibly changes during irradiation. • A reduction parameter can be used as a hint of their health status. • This method can be easily implemented in brightfield optical microscopes. [ABSTRACT FROM AUTHOR]

This article gives an overview of activists of the Africans Rising movement who participated in a pilot retreat for a month in Arusha, northern Tanzania. It gave them the opportunity to examine and share the strategies that they employ to deal with the restrictions on civil society seen across Africa. Africans Rising is a nascent, rapidly growing, self-identifying collective of social movements, non-governmental organisations (NGOs), artists, sports people, cultural activists and others. The retreat was a meeting of east, west, south and north Africa and showcased the diversity and richness of the people of Africa with activists from Benin, Burundi, Democratic Republic of Congo, Kenya, Liberia, Morocco, Senegal, Somalia, Tanzania and Uganda. [ABSTRACT FROM AUTHOR]

Due to the general demographic situation in Hungary and the recent overall crisis of this traditional settlement-type, Hungarian small towns have been facing an intensive shrinking since the last decade. Although natural decrease and migration loss are almost equal factors of population decline, outmigration seems to be a more strategic, critical problem for these settlements. There are hardly any reliable data available about the migrants leaving small towns, but some of them seem to support the wellknown assumption that the young people, who leave these towns are looking for wider horizons and better perspectives. The aim of the present paper is to analyse the outmigration of young adults from small towns, and give estimation about the international aspects of migration, which is hardly ever published in official statistics. The paper also aims at revealing the impact of the intensive migration on the local labour market. A short statistical analysis based on census data and two empirical surveys conducted by the authors are also included. One was carried out with the support of volunteer contributors, former small-town students, who tried to reconstruct the post-secondary school migration of their former classmates. The other survey contains a series of interviews focusing on the consequences of the young adults' migration on the labour market. The results facilitate the estimation regarding the (weak) capability of small towns to keep their young population, and highlight the problems of local developmental options within the context of demographic shrinkage. [ABSTRACT FROM AUTHOR]

This article gives an overview of activists of the Africans Rising movement who participated in a pilot retreat for a month in Arusha, northern Tanzania. It gave them the opportunity to examine and share the strategies that they employ to deal with the restrictions on civil society seen across Africa. Africans Rising is a nascent, rapidly growing, self-identifying collective of social movements, non-governmental organisations (NGOs), artists, sports people, cultural activists and others. The retreat was a meeting of east, west, south and north Africa and showcased the diversity and richness of the people of Africa with activists from Benin, Burundi, Democratic Republic of Congo, Kenya, Liberia, Morocco, Senegal, Somalia, Tanzania and Uganda. [ABSTRACT FROM AUTHOR]

The stress influence on a Ti 0.85 Zr 0.15 Mn 1.33 V 0.3 alloy during hydrogenation cycles has been studied in a special design test cell for mechanical studies during hydrogenation. The alloy was synthesized in an induction melting furnace with an inert Ar atmosphere. The full basic characterization of the material is presented, from a structural and morphological point of view by X-ray powder diffraction (XRPD), Scanning Electron Microscopy (SEM), Energy Dispersion X-ray spectroscopy (EDX) and laser grain size analysis, and, from a thermodynamic point of view by the measure of the Pressure composition Isotherms (P-c-I) at 23 and 80 °C. Besides, in order to measure the mechanical properties of the material, volume variations measurements during hydrogenation cycles were performed. The samples were milled up to sizes beneath 1.25 mm, and afterwards placed into a cylindrical die under three different levels of axial stress, 0.0325 MPa, 0.12 MPa and 0.84 MPa, for more than 100 cycles. For higher stress levels the powder bed shrinks as cycles continue, while for lower stresses the powder bed swells. A natural tendency for the powder to decrepitate and agglomerate was observed, as the size distribution of the particles reduces and the shape become uneven, generating an increase of the porosity and volume in the case of the lower stress sample. As the stress increases, the grains rearrange easily and a polydisperse distribution of particles facilitates the accommodation of smaller grains between bigger ones, producing a reduction in the porosity and volume of the hydride bed after several cycles. [ABSTRACT FROM AUTHOR]

While the income per capita in the developing world since the turn of the Millennium has grown faster than that of the developed world, the question whether there is an ongoing process of catching up between countries remains. The notion of income convergence has provided many insights into the sources for long-run growth but has largely neglected the role of social capabilities in economic development. By social capabilities we mean the qualification of the 'theory of convergence' which asserts that productivity growth rates between countries tend to vary inversely with regard to productivity levels. The social capabilities approach holds that a country's potential for rapid growth is strong when "it is technologically backward but socially advanced" (see Abramovitz, 1986:388). This means that the potential to catch up under globalization is strongest for countries in which social capabilities are developed to allow successful use of technologies and where institutional arrangements are conducive to economic progress. Yet there is no clear agreement in the literature on the main components of social capabilities or how to measure them. Our framework argues that the role of capabilities in catching up needs to understand them in terms of structural transformation, economic and social inclusion, state's autonomy and accountability. Without progress in these dimensions within-country inequality may increase and might in turn lead to stagnating growth and slim prospects for global income convergence. [ABSTRACT FROM AUTHOR]

To evaluate the effect of different cooking methods on the losses of restructured beef rolls, was the objective of the work. For its execution were prepared temples of 20 kg, the meats were ground by a pre cutter disc of three orifices in the form of kidney and blade of two arms. The products were made using sodium tripolyphosphate, common salt, sodium ascorbate, the sodium alginate-calcium carbonatesodium ascorbate mixture, citric acid, soy isolated and spices, which were combined to obtain six variants. Each variant and the pattern of intact muscle (white bowls and kidney) were fried, steamed, microwaved and dry heat, making a total of six replicates. In order to evaluate the effect of the different cooking methods on the restructured meat roll, the losses by cooking and the percentage of shrinkage by frying were measured. Regardless of the binder used, the heat treatments in steam oven and frying were the best results reported. The other binders used: sodium carrageenan, isolated soy protein and potato starch, plus the addition of common salt and sodium tripolyphosphate, resulted in restructured products of losses lower than their intact muscle patterns, but always superior to the products obtained with common salt and sodium tripolyphosphate in their maximum doses. [ABSTRACT FROM AUTHOR]

While swelling and shrinking of multiple emulsions – depending on existing pressure gradients – has been well reported in the literature, little research has been carried out covering the osmotic equilibration between pressure systems caused by interfacial phenomena and phase fractions for multiple emulsions in which either one or both disperse phases exhibit a phase fraction above the maximum packing limit without any deformation of the droplets. In this paper, a model for determining the theoretical equilibrium state regarding osmotic regulation is presented, as well as a new experimental method to determine the disperse phase fraction. This method is employed to compare the measured phase fractions to the theoretical predictions. Using both experimental and theoretical approaches, a direct method is proposed to define the disperse phase fraction and the encapsulation efficiency, yielding potential for a knowledge driven improvement of the production of multiple emulsions. [ABSTRACT FROM AUTHOR]

A new type of combined energy absorber working on the principle of shrinking and expanding of the circular metal tube was proposed. First, quasi-static experiments of aluminum alloy tubes were conducted. The results show that this type of energy absorber is completely feasible. Afterward, finite element models were established to estimate the tube deformation and force–displacement response, which were in good agreement with the experimental results. A theoretical solution for the steady-state crushing force of the tube was derived. Moreover, the effects of various structural parameters were investigated using a validated finite element model. According to the results, the force increases with the increase of the wall thickness and has a monotonically decreasing relationship with the radius of the shrinking die, but it first decreases, then increases with the increase in the cone angle of the expanding die. Compared with the energy absorber that only produces shrinking deformation, the steady-state force of the combined absorber is increased by 123%, and the energy absorption under the same stroke is higher. The result can provide guidance for the optimal design of the collision energy-absorbing structure on a rail vehicle. • A novel energy absorber combines shrinking and expanding of a circular metal tube. • Deformation process and force response are analyzed by experiment and FEA methods. • A theoretical solution for the steady-state force of the tube is derived. • Effects of the geometric parameters on crashworthiness are investigated. • Combined absorber has a higher energy absorption efficiency. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to investigate numerically the dynamics of quantized vortex loops, just before the reconnection at finite temperature, when mutual friction essentially changes the evolution of lines. Modeling is performed on the base of vortex filament method using the full Biot-Savart equation. It was discovered that the initial position of vortices and the temperature strongly affect the dependence on time of the minimum distance $$\delta (t)$$ between tips of two vortex loops. In particular, in some cases, the shrinking and collapse of vortex loops due to mutual friction occur earlier than the reconnection, thereby canceling the latter. However, this relationship takes a universal square-root form $$\delta \left( t\right) =\sqrt{\left( \kappa /2\pi \right) \left( t_{*}-t\right) }$$ at distances smaller than the distances, satisfying the Schwarz reconnection criterion, when the nonlocal contribution to the Biot-Savart equation becomes about equal to the local contribution. In the 'universal' stage, the nearest parts of vortices form a pyramid-like structure with angles which neither depend on the initial configuration nor on temperature. [ABSTRACT FROM AUTHOR]

In a wide range of practical problems correlation matrices are formed in such a way that, while symmetry and a unit diagonal are ensured, they may lack semidefiniteness. We derive a variety of new upper bounds for the distance from an arbitrary symmetric matrix to the nearest correlation matrix. The bounds are of two main classes: those based on the eigensystem and those based on a modified Cholesky factorization. Bounds from both classes have a computational cost of O(n³) flops for a matrix of order n but are much less expensive to evaluate than the nearest correlation matrix itself. For unit diagonal A with |aij| ≤ 1 for all i ≠ j the eigensystem bounds are shown to overestimate the distance by a factor at most 1 + n√n. We show that for a collection of matrices from the literature and from practical applications the eigensystem-based bounds are often good order of magnitude estimates of the actual distance; indeed the best upper bound is never more than a factor 5 larger than a related lower bound. The modified Cholesky bounds are less sharp but also less expensive, and they provide an efficient way to test for definiteness of the putative correlation matrix. Both classes of bounds enable a user to identify an invalid correlation matrix relatively cheaply and to decide whether to revisit its construction or to compute a replacement, such as the nearest correlation matrix. [ABSTRACT FROM AUTHOR]

Indefinite approximations of positive semidefinite matrices arise in various data analysis applications involving covariance matrices and correlation matrices. We propose a method for restoring positive semidefiniteness of an indefinite matrix M0 that constructs a convex linear combination S(α) = αM1 + (1 - α)M0 of M0 and a positive semidefinite target matrix M1. In statistics, this construction for improving an estimate M0 by combining it with new information in M1 is known as shrinking. We make no statistical assumptions about M0 and define the optimal shrinking parameter as α* = min{α ϵ [0, 1] : S(α) is positive semidefinite}. We describe three algorithms for computing α* . One algorithm is based on the bisection method, with the use of Cholesky factorization to test definiteness; a second employs Newton's method; and a third finds the smallest eigenvalue of a symmetric definite generalized eigenvalue problem. We show that weights that reflect confidence in the individual entries of M0 can be used to construct a natural choice of the target matrix M1. We treat in detail a problem variant in which a positive semidefinite leading principal submatrix of M0 remains fixed, showing how the fixed block can be exploited to reduce the cost of the bisection and generalized eigenvalue methods. Numerical experiments show that when applied to indefinite approximations of correlation matrices shrinking can be at least an order of magnitude faster than computing the nearest correlation matrix. [ABSTRACT FROM AUTHOR]

We performed voxel-guided morphometry (VGM) investigating the mechanisms of brain atrophy in multiple sclerosis (MS) related to focal lesions. VGM maps detect regional brain changes when comparing 2 time points on high resolution T1-weighted (T1w) magnetic resonace imaging (MRI). Two T1w MR datasets from 92 relapsing-remitting MS patients obtained 12 months apart were analysed with VGM. New lesions and volume changes of focal MS lesions as well as in the surrounding tissue were identified by visual inspection on colour coded VGM maps. Lesions were dichotomized in active and inactive lesions. Active lesions, defined by either new lesions (NL) (volume increase > 5% in VGM), chronic enlarging lesions (CEL) (pre-existent T1w lesions with volume increase > 5%), or chronic shrinking lesions (CSL) (pre-existent T1w lesions with volume reduction > 5%) in VGM, were accompanied by tissue shrinkage in surrounding and/or functionally related regions. Volume loss within the corpus callosum was highly correlated with the number of lesions in its close proximity. Volume loss in the lateral geniculate nucleus was correlated with lesions along the optic radiation. VGM analysis provides strong evidence that all active lesion types (NL, CEL, and CSL) contribute to brain volume reduction in the vicinity of lesions and/or in anatomically and functionally related areas of the brain. [ABSTRACT FROM AUTHOR]

We consider the problem of separating maximally violated inequalities for the precedence constrained knapsack problem. Though we consider maximally violated constraints in a very general way, special emphasis is placed on induced cover inequalities and induced clique inequalities. Our contributions include a new partial characterization of maximally violated inequalities, a new safe shrinking technique, and new insights on strengthening and lifting. This work follows on the work of Boyd (1993), Park and Park (1997), van de Leensel et al. (1999) and Boland et al. (2011). Computational experiments show that our new techniques and insights can be used to significantly improve the performance of cutting plane algorithms for this problem. [ABSTRACT FROM AUTHOR]

As a potential host rock for deep geological disposal of radioactive waste, the Callovo-Oxfordian and Opalinus clay rocks have been extensively investigated in the laboratory with respect to deformation under various thermo-hydro-mechanical conditions: (1) stresses covering the range from the initial lithostatic state to redistributed levels after excavation, (2) humidity variations representing ventilation during operation of tunnels as well as water migration from the far-field and (3) heating from ambient temperature up to 100 °C and a subsequent cooling phase. For these highly consolidated clay rocks, a new concept is theoretically derived to explain the effective stress in the particle matrix and experimentally confirmed. The mechanical deformation of the clay rocks is determined by means of short- and long-term compression experiments on quasi water-saturated samples at ambient temperature. Reponses of the clay rocks to humidity changes are examined by drying and wetting the samples under different loading conditions. Thermal effects are studied by heating and cooling the stressed samples under drained and undrained conditions. The main findings are presented and discussed in this paper. [ABSTRACT FROM AUTHOR]

Gasification of wood pellets in downdraft gasifier is confronted with the problem of granulated fuel agglomeration. It occurs when the wood pellets are moving from the pyrolysis zone to the oxidation zone and pellets stick together in lumps, which disrupts the movement of fuel and stops further process. In order to investigate the cause and regularities of fuel agglomeration, experimental studies of wood pellets thermal deformations during pyrolysis were carried out. Experimental studies were performed in an electrically heated horizontal tubular furnace from 300 °C to 1000 °C temperature in an inert atmosphere capturing wood pellet thermal deformations by a digital camera. During investigation the center temperature of the pellet was also measured. Analyzed results showed that wood pellet final diameter decreased when the heating temperature increased. It was also established that the pellet expanded from 400 °C to 900 °C heating temperature at the beginning of pyrolysis process. The maximum swelling effect was reached at 550 °C temperature and after it swelling intensity was decreasing till 900 °C temperature. Over 900 °C heating temperature, the expansion phenomenon was no longer visible. The tendency of wood pellet size alteration (swelling and shrinking) depends on heating temperature. The obtained results explain the reason for adhesion of wood pellets in the gasifier and reveal regularity of wood pellet size changes with increasing heating temperature. [ABSTRACT FROM AUTHOR]

This paper researches a type of absorber of kinetic collision energy that works on the principle of shrinking and splitting a tube of circular cross section. During collision, a seamless tube is thrust through a cone bush, squeezing the tube. Energy is absorbed by the plastic deformation, and through the friction between the tube and the bush. After passing through the cone bush, the tube presses against a splitter, and further energy is lost to friction and plastic deformation during the splitting process. Grooves on the inner wall of the tube prevent uncontrolled longitudinal tearing of the wall during the splitting. This new combined method of energy absorption enables greater absorption power with compact dimensions. Scaled samples have been tested in the laboratory. The influence of geometry and manufacturing technology of the samples, as well as the benefits of using such an absorber, are presented and discussed in this paper. The results show that the combined absorber has approximately 60% higher absorption power than the shrinking absorber by itself. [ABSTRACT FROM AUTHOR]

Objective We investigated the temporal variation of soil bulk density (BD) in a semiarid Macrochloa tenacissima grassland where BD plays a key role in the soil–plant feedback mechanisms that are responsible for the patchy distribution of vegetation. Methods We used the core method to analyse the soil BD in two experimental sites in microsites that were representative of the spatial heterogeneity of soils and vegetation. The study was performed over two years, in winter (three times) and summer (twice). We studied the changes in BD in relation to the rainfall and to the soil properties that describe or affect the soil structural conditions, such as soil moisture, particle-size, clay mineralogy, the contents of various organic carbon fractions and certain microaggregation indices. Results We found a consistent temporal variation in BD, which was lower in winter (1.22 ± 0.02 g/cm 3 , average ± SEM) than in summer (1.33 ± 0.02 g/cm 3 ) and depended on the rainfall in the weeks before sampling. The greatest change was observed during the first year of study, when the wettest winter and the driest summer occurred. The variation of BD was most pronounced in the mounds developed under senescent plants (+ 16.7% average increase from winter to summer), intermediate under adult plants and in the residual mounds (+ 8.9%) and was weak in the soils of the bare areas or under young plants (+ 5.1%). This implies that the microtopography should get steeper in winter and flatter in summer. The largest changes in BD were correlated with variables representing organic matter and its action in adhering soil particles. Conclusion We observed consistent temporal variations in BD that were spatially heterogeneous and related to wet conditions in the soils studied. Research is needed to establish the mechanisms responsible for the changes in BD, which may include greater activity of roots and fauna during the wet season and the enrichment in labile organic fractions that are hygroscopic and can bind soil particles into temporary aggregates. Practice implications Spatially heterogeneous temporal variation in BD must be taken into account in inventories of soil nutrients, water or carbon. Moreover, it implies an increased porosity under vegetated patches just when the soil receives the most rainfall, resulting in a positive feedback of plant growth and mound formation. This mechanism might be added to those already described for plant–soil feedbacks in dry lands. [ABSTRACT FROM AUTHOR]

Abstract: Consider the Cauchy–Dirichlet problem in half space for a one-dimensional evolution p-Laplacian with convection for , and pay attention to the interface . It is well known that in the absence of the convection, while the inclusion of the first-order term may change the property of finite (or infinite) speed of propagation. In this paper, it will be shown that the nonlinear convection plays a very important role to the evolution of . For the convection with promoting diffusion, the fast propagation phenomenon occurs (i.e. whenever ) if the convection is strong enough, otherwise, remains finite and non-localized. While under the convection with counteracting diffusion, if the convection is strong enough, localization (even shrinking and extinction) appears, otherwise, keeps non-localized. In addition, it is found that the time-related boundary data are significant also to the behavior of solutions: the decay or incremental rates of the boundary data affect not only the contraction or expansion of the supports, but also the propagation speed of the interface. [Copyright &y& Elsevier]