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Kerogen has a lower affinity to hydrogen than methane; thus, it allows hydrogen to flow more easily, but it is unclear how the permeabilities of hydrogen and methane differ. This study determines the single-phase permeability of hydrogen and compares it with methane permeability in organic-rich caprock. It takes into account adsorption to the pore wall and slippage at the boundary. It implements the two processes at 370 K for pressures from 500 to 4000 psi to obtain the hydraulic conductance of a sub-100-nm conduit. It then relates them to the macroscopic behavior via network modeling. Lower pressures represent depleted gas reservoirs in the subsurface. Decreasing pore pressure enhances hydrogen transport by reducing its adsorption to the pore wall and transitioning its behavior from continuum to discrete particles, leading to first- or second-order slippage. The results show that hydrogen conductance, q i n − s i t u (H 2), is always larger than the reference conductance without adsorption and slippage (q 0). Hydrogen permeability, k i n − s i t u (H 2), is also larger than methane permeability, k i n − s i t u (CH 4), while the permeability values differ by 70% − 130%, depending on the pore pressure. This study also determines the conduit size corresponding to the ratio of hydrogen permeability to methane permeability at in-situ conditions by comparing it with the ratio of hydraulic conductance of hydrogen to methane. The results have applications in underground hydrogen storage by indicating how hydrogen flow changes with pressure in ultra-tight formations. [Display omitted] • This study investigates H 2 permeability in organic-rich caprock in the subsurface. • It quantifies the effects of adsorption and slippage for H 2 in the nanosize conduit. • Slippage dominates H 2 flow, and the effects of adsorption are negligible. • H 2 conductance is higher than CH 4 conductance because H 2 adsorbs less to kerogen and slips more. • H 2 permeability is almost twice the CH 4 permeability in the organic-rich caprock. [ABSTRACT FROM AUTHOR]

Degenerative lumbar spondylolisthesis (DLS) is a prevalent spinal condition that can result in significant disability. DLS is thought to result from a combination of disc and facet joint degeneration, as well as various biological, biomechanical, and behavioral factors. One hypothesis is the progressive degeneration of segmental stabilizers, notably the paraspinal muscles, contributes to a vicious cycle of increasing slippage. To examine the correlation between paraspinal muscle status on MRI and severity of slippage in patients with symptomatic DLS. Retrospective cross-sectional study at an academic tertiary care center. Patients who underwent surgery for DLS at the L4/5 level between 2016–2018 were included. Those with multilevel DLS or insufficient imaging were excluded. The percentage of relative slippage (RS) at the L4/5 level evaluated on standing lateral radiographs. Muscle morphology measurements including functional cross-sectional area (fCSA), body height normalized functional cross-sectional area (HI) of Psoas, erector spinae (ES) and multifidus muscle (MF) and fatty infiltration (FI) of ES and MF were measured on axial MR. Disc degeneration and facet joint arthritis were classified according to Pfirrmann and Weishaupt, respectively. Descriptive and comparative statistics, univariable and multivariable linear regression models were utilized to examine the associations between RS and muscle parameters, adjusting for confounders sex, age, BMI, segmental degeneration, and back pain severity and symptom duration. The study analyzed 138 out of 183 patients screened for eligibility. The median age of all patients was 69.5 years (IQR 62 to 73), average BMI was 29.1 (SD±5.1) and average preoperative ODI was 46.4 (SD±16.3). Patients with Meyerding-Grade 2 (M2, N=25) exhibited higher Pfirrmann scores, lower MF fCSA and MF HI , and lower BMI, but significantly more fatty infiltration in the MF and ES muscles compared to those with Meyerding Grade 1 (M1). Univariable linear regression showed that each cm2 decrease in MF fCSA was associated with a 0.9%-point increase in RS (95% CI -1.4 to - 0.4, p<.001), and each cm2/m2 decrease in MF HI was associated with an increase in slippage by 2.2%-points (95% CI -3.7 to -0.7, p=.004). Each 1%-point rise in ES FI and MF FI corresponded to 0.17%- (95% CI 0.05–0.3, p=.01) and 0.20%-point (95% CI 0.1–0.3 p<.001) increases in relative slippage, respectively. Notably, after adjusting for confounders, each cm2 increase in Psoas fCSA and cm2/m2 in Psoas HI was associated with an increase in relative slippage by 0.3% (95% CI 0.1–0.6, p=.004) and 1.1%-points (95% CI 0.4–1.7, p=.001). While MF fCSA tended to be negatively associated with slippage, this did not reach statistical significance (p=.105). However, each 1%-point increase in MF FI and ES FI corresponded to increases of 0.15% points (95% CI 0.05–0.24, p=.002) and 0.14% points (95% CI 0.01–0.27, p=.03) in relative slippage, respectively. This study found a significant association between paraspinal muscle status and severity of slippage in DLS. Whereas higher degeneration of the ES and MF correlate with a higher degree of slippage, the opposite was found for the psoas. These findings suggest that progressive muscular imbalance between posterior and anterior paraspinal muscles could contribute to the progression of slippage in DLS. [ABSTRACT FROM AUTHOR]

This work introduces two innovative rolling pair concepts to minimize slippage and reduce mass in cam-roller systems of large-scale hydraulic drivetrains: The variable contact length and the Shifting Contact Geometry concepts. Both aim to improve traction in the low contact force phase in cyclically loaded rolling contacts. The shifting contact geometry concept was validated using three custom rolling contacts: a line contact, a double elliptical contact, and a combination of both (i.e., shifting contact geometry). The tests were conducted under synchronized cyclic loading to mimic the conditions in a hydraulic drivetrain. Furthermore, a model from previous work was implemented to make predictions and compare them against the experimental results. During preliminary tests, the double elliptical contact displayed superior tractive behavior than the line contact under the same load thanks to higher contact pressures. Under synchronized cyclic loading, the line contact displayed high sensitivity to applied resisting torques at low contact forces, leading to high slide-to-roll ratios and traction force peaks. In contrast, the rolling pair with shifting contact geometry exhibited minimum slippage even under high resisting torques, resulting in substantially lower (and in most cases negligible) slide-to-roll ratio and traction force peaks. The simulations also captured this behavior, proving the validity of the model for predicting and comparing the rolling-sliding dynamics of these two different rolling pairs. This study demonstrates that rolling pairs with shifting contact geometry can not only improve the tribological performance of cam-roller contacts in large-scale hydraulic drivetrains but also yield a more favorable dynamic behavior. [ABSTRACT FROM AUTHOR]

This study proposes to study the sliding and slippage mesoscopic defects that appear during the preforming phase of dry reinforcements to produce complex composite shapes. For this purpose, experimental preforming tests were conducted on a plain weave fabric with low cohesion using a specific punch developed specifically for this purpose, and which combines the geometric facets of a square and a tetrahedron. The tests were conducted under several configurations varying the blank holder pressure intensity as well as its distribution, through the number and springs position that generate normal forces on the blank holders. The results showed that the corners of the geometry formed by orthogonal faces favor the appearance of mesoscopic defects and specifically slippage because of its severity. Sliding has shown itself to be very sensitive both to the singularities of the geometry where it appears, and to the heterogeneity of the pressure distribution of the blank holders. On the other hand, the sliding, which appears in the vicinity of the slippage on flat faces, is rather sensitive to the distribution of the pressure. The increase in the blank holder pressure, regardless of the conditions of its application, leads to an almost linear increase in the extent and number of these mesoscopic defects. [ABSTRACT FROM AUTHOR]

Although an important theoretical tool within the field of critical study of men and masculinities, mishandling of Connell's theory of multiple masculinities and subsequent developments frequently overlooks the relational and legitimizing components central to the hegemonic masculine construct, producing conceptual 'slippage'. This case study demonstrates such misapplication, examining four investigations within the emerging field of research concerning the antifeminist masculine performances and ideological constructs associated with involuntary celibates (incels). Each study lacks acknowledgement and demonstration of the political mechanics of relational legitimacy that define hegemonic masculinity, producing, instead, trait analyses of non-hegemonic dominant or dominating masculine behaviour resting on fixed, often toxic character types. As novel and emergent communities of men receive scholarly attention, it is important researchers heed repeated attempts to guide correct use of theory by engaging with the history and evolution of employed concepts. [ABSTRACT FROM AUTHOR]

In 2007, the American Iron and Steel Institute (AISI) established a standard for cold-formed steel–special bolted moment frames (CFS-SBMFs). This structural system is designed to resist seismic forces. The CFS-SBMF system employs double-channel beams and square hollow structural section (HSS) columns that are bolted together to create a sturdy and robust structural frame. However, the CFS-SBMF system is only suitable for constructing one-storey buildings, and ASCE 7 prohibits its use in buildings with a height of over one storey. This study was conducted to expand the use of CFS-SBMFs to the construction of multi-storey low-rise buildings. Firstly, a new moment connection detail is proposed, and a design procedure is proposed to ensure that bolted connections, instead of beams or columns, have the ductility to withstand seismic forces. Secondly, the proposed design procedure for bolted connections was verified through full-scale cyclic testing. Finally, a comprehensive evaluation was undertaken to evaluate the proposed structural system's performance under seismic excitation. The evaluation included nonlinear dynamic analysis and incremental dynamic analysis (IDA) according to FEMA P695, which provided a detailed understanding of the seismic design factors (SDFs) in multi-storey low-rise CFS-SBMF buildings. [ABSTRACT FROM AUTHOR]

Sustainable management of water and sanitation is inextricably linked with women's health and well-being. This paper investigates slippage in sanitation, experienced by women beneficiaries of the Swacch Bharat Mission Rural programme through Amartya Sen's conception of justice. A total of 135 individuals were interviewed from 49 households in Kanjadwa and Madhnagar Manoharpur Gram Panchayats, Shravasti, India, out of which 90 were women. As per findings, 30% of women practice open defaecation despite possessing toilets, resulting in slippage. The Sanitation Well-being framework is deployed to study slippage and its linkage with women's agency. Personal, cultural, and structural factors contributing to this are child marriage, denial of education and employment opportunities, slut shaming, victim blaming, domestic violence, and character assassination. These are made worse by the state adoption of misogynistic IEC messages that reinforce cultural stereotypes and worsen women's condition. In the quest to attain ODF status in Ikauna Block, UP, the current sanitation programme became a tool of suppression. Consequently, we understand that open defaecation among women is an outcome of the basic unfreedoms rather than a volitional choice that prevents them from experiencing sanitation well-being. [ABSTRACT FROM AUTHOR]

The unbonded flexible riser has been increasingly applied in the ocean engineering industry to transport oil and gas resources from the seabed to offshore platforms. The slippage of helical layers, especially the tensile armor layers of unbonded flexible risers, contribute to the nonlinear hysteresis phenomenon, which is a research hotspot and difficulty. In this paper, on the basis of a typical eight-layer unbonded flexible riser model, the nonlinear slippage of a tensile armor layer and the corresponding nonlinear behavior of an unbonded flexible riser subjected to irregular external loads are studied by numerical modeling with detailed cross-sectional properties of the helical layers, and are verified through a theoretical method considering the coupled effect of the external loads on the unbonded flexible riser. Firstly, the balance equation of each layer considering the effect of external loads is established based on functional principles, and the overall theoretical model of the unbonded flexible riser is set up in consideration of the contact between adjacent layers. Secondly, the numerical modeling of each separate layer within the unbonded flexible riser, including the actual geometry of the carcass and pressure armor layer, is established, and solid elements are applied to all the interlayers, thus simulating the nonlinear contact and friction between and within interlayers. Finally, after verification through test data, the behavior of the unbonded flexible riser under the cyclic axial force, torsion, bending moment, and irregular external and internal pressure is studied. The results show that the tensile armor layer can slip under irregular loads. Additionally, some suggestions related to the analysis of unbonded flexible risers under irregular loads are drawn in the end. [ABSTRACT FROM AUTHOR]

This paper explores the time-evolving behaviour of an optically dense fluid in proximity to a vertically oscillating plate with a slip condition. By utilizing the Laplace transform (LT) method, the non-dimensional governing equations are resolved. The study delves into the influence of various parameters on the velocity and temperature distributions and the shear stress and heat transfer rate, presenting these effects through detailed graphical visualizations and thorough analysis. The dynamics of the fluid flow are extensively discussed, particularly contrasting the behaviours in scenarios involving an oscillated plate (OP) and a stationary plate (SP). It is observed that the fluid velocity is consistently higher in the presence of an oscillated plate. The shear stress on the plate upsurges with more intense cooling or heating, while an upswing in the slip parameter tends to reduce the shear stress. Furthermore, the heat transfer rate across the plate is raised with an amplified radiation parameter. The insights from this study have significant implications for various engineering fields, including aerospace and environmental engineering, with practical applications in the design and optimization of heat exchangers, cooling systems, chemical reactors, and in understanding ocean currents near dynamically changing coastal structures. [ABSTRACT FROM AUTHOR]

ABSTRACT Wheel slipping and fuel consumption are variables influenced by tire pressure, speed, ballasting, and soil surface. Once the tractor is present in all agricultural operations, knowledge of these variables is essential to achieving the most operational efficiency. This study aimed to develop an embedded system to collect data and show tractor slipping and fuel consumption in real-time via smartphone. The system was developed using prototyping platforms and validated through randomized field tests under four speeds and two terrain conditions. Three methods for determining slippage under different conditions were compared. The developed embedded system determined an agricultural tractor's slipping and fuel consumption conditions. The slip and fuel consumption rates varied depending on the type of rolling surface (ground preparations) and the tractor's operating speeds. Conventional tillage surface increased fuel demand by 6% and slippage by 17% compared to no-till rates. The proposed embedded system found similar results and could present the slipping values in the developed Android to real-time operation compared to a conventional method. This application shows both slipping and fuel consumption values over time on graphs, which can be very useful during machine operation, helping to define better configuration and reduce environmental impacts.

Purpose: The number of seven required throws per knot was previously reported as providing sufficient security against slippage. A novel high-strength suture featuring dynamic tightening may allow for throw number reduction without compromising stability. The aims of this study were to (1) investigate the influence of the throw number and the effect of different ambient conditions on the knot security of two different high-strength sutures, and (2) compare their biomechanical competence. Methods: Two sutures (FiberWire (FW) and DynaCord (DC)) were considered for preparing alternating surgical knots. The specimens were stratified for exposure to different media during biomechanical testing—namely air (dry), saline solution (wet), and fat (fatty-wet). A monotonic tensile ramp loading to failure was applied in each test run. For each suture and ambient condition, seven specimens with three to seven throws each were tested (n = 7), evaluating their slippage and ultimate force to failure. The minimum number of throws preventing suture unraveling was determined for each suture type and condition. Results: For each suture type and condition, failure occurred via rupture in all specimens for the following minimum number of throws: FW—dry–7, wet–7, fatty-wet–7; DC—dry–6, wet–4, fatty-wet–5. When applying seven throws, FW demonstrated significantly larger slippage (6.5 ± 2.2 mm) versus DC (3.5 ± 0.4 mm) in wet (p = 0.004) but not in dry and fatty-wet conditions (p ≥ 0.313). Conclusions: The lower number of throws providing knot security of DC versus FW in the more realistic wet and fatty-wet conditions indicates that the novel DC suture may allow to decrease the foreign body volume and save surgical time without compromising the biomechanical competence. [ABSTRACT FROM AUTHOR]

Based on new language data, the present paper attempts to answer the question of whether masculine generics are indeed fully inclusive and refer to the same extent to women and men. The author argues that this is not the case as proved in an examination of the hitherto uninvestigated phenomenon in Polish of the socalled slippage from the generic item to its masculine exemplifications (e.g. podatnik ‘taxpayer’ > Kowalski ‘male surname’). It is also shown through the results of an original questionnaire study with university student participants. The study inquired about the students’ male and female connotations with masculine generics denoting people involved in politics, sports, art and science (e.g. naukowiec ‘scholar, masc.’) in comparison to phrases with two genders (e.g. naukowiec ‘scholar’/ naukowczyni ‘female scholar’). The forms of the nouns were provided in two orders and the responses studied in relation to participants’ gender. The results are interpreted in terms of the cognitive prototype theory, according to which the prototypical human is male, as expressed by the androcentric rule ‘people = male’. [ABSTRACT FROM AUTHOR]

Elevators are the most common transportation tool in modern buildings. To satisfy the safety requirement, it is mandatory to carry out regular maintenance in a certain period of time. Among maintenance items, the determination of the traction compartment cable slippage status is one of the greatest challenges in the elevator industry, but a simple and effective method is still lacking. Currently, in a real situation, the inspection accuracy relies considerably on suitable personnel experiences, and the inspection process is also time-consuming. Accordingly, we aim to develop an automatic streaming image process model for the detection of the elevator cable slipping distance. First, the geometric shape of an ellipse is established from a captured circle image. Second, the ellipse is averaged and segmented into 360° with a predefined label as a reference point. Third, the circumference formula is applied to the calculation of the cable slipping distance. Finally, the outcome of the arithmetic operation is sent to the cloud database through a graphical user interface (GUI) on the web for monitoring purposes. The experimental results reveal that the standard deviation is as small as 1.153 mm, and the measurement uncertainty is only 0.258 mm, demonstrating high accuracy, rapidity, and robustness. [ABSTRACT FROM AUTHOR]

To reduce slippage between the sensing module mounted on the tight-fitting clothing and the human skin during body movement, the clothing was optimized by numerical simulation. Firstly, solid models of the upper body and the sleeveless tight-fitting clothing were established using the reverse engineering software Geomagic Studio. Secondly, the sleeveless tight-fitting clothing was cut and segmented by the structural style of the tight-fitting clothing and the range of the skin deformation in each area. Finally, taking the running movement of the body as an example, the finite element analysis platform ANSYS Workbench was used to study the position change of sensing module mounting points relative to the human skin when different elastic fabrics were combined into the clothing. The results showed that when fabrics with higher elasticity were selected for front and back pieces and fabrics with lower elasticity were selected for shoulder and side pieces, the slippage between the sensing module and the human skin was smaller. [ABSTRACT FROM AUTHOR]

Based on two analytical approaches (Prandtl model and von Kármán model), turbulent flow in a cylindrical channel with flow slippage on the wall was considered. The results of the analytical solution are supplemented with numerical simulations based on the lattice Boltzmann model (LBM). Validations of the analytical model against numerical computations showed their good agreement. The analytical model enabled obtaining relations for the velocity profile, hydraulic resistance coefficient and Stanton number, which make it possible to evaluate the influence of the slip effect (Kn) and the flow rate (Re) on their variation. [ABSTRACT FROM AUTHOR]

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process windows. Within this work, an effort is made to closely investigate and understand the process limits caused by excessive slippage of the workpiece. Optical measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process limit. Large differences in slippage were observed, depending on the tribological system. While systems with polymer based lubricants showed excessive slippage at low stroke rates, systems using oil or no lubricant endured higher stroke rates before process limits were reached. The optical measurements revealed three major forms of slippage: successful rolling without slippage, failure due to excessive slippage at process start, and failure due to excessive slippage at around one workpiece rotation. [ABSTRACT FROM AUTHOR]

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A non-trivial problem in the biped walking is the preservation of stability under external influences without slowing down velocity. A dynamic walking control algorithm with a hierarchical structure is proposed in the article. The lower control level is organized according to the principle of tracking drives and ensures the position of the robot`s body using all given possible coordinates. The problem of traffic stabilization is solved at the upper level. An ideal mechanism — a flat inverted mathematical pendulum is considered in the feedback circuit. Its equations are synchronized by the moment of the step ending. Particular attention is paid to the interaction of the robot foot with the support surface to determine the conditions for the absence of slippage. Proposed control approach makes it possible to control the current position of the robot`s structure in the space in different walking modes without slowing down velocity. Critically assessing the results and prospects of the research, we can conclude about their use-fulness in the development of artificial intelligence cooperation with humans, about possible applications in everyday life, a specific environment and industry. The proposed approach may be applicable to the control of the walking mechanisms of similar mobile robots.

The current work seeks to investigate the thermal bio-convection impact of gyrotactic microorganisms in a Cross nano liquid flow through a slippery horizontal cylinder with Arrhenius activation energy involvement. This nanofluid model incorporates magnetic field, chemical reaction, Brownian motion, thermophoresis, and gravitation. The set of nonlinear formulating PDEs is converted to a set of ODEs by utilising requisite similarity transformations. The numerical computation of the altered ODEs is performed using the fourth-order Runge-Kutta-Fehlberg approach plus shooting strategy. The physical consequences of significant physical factors on non-dimensional profiles of interest are displayed in the form of figures and tables. The outcomes revealed that raising the activation energy and chemical reaction parameters significantly increases nanoparticle concentration. However, the microorganism's concentration difference parameter may be used to control the process of microorganism intensity. Using Response-Surface-Methodology (RSM), the statistical analysis (SA) of Nusselt and Sherwood numbers is performed to investigate the effectiveness of activation energy, thermophoresis, and Brownian motion parameters. Activation energy and thermophoresis parameters are both favourably sensitive to the Nusselt number. The study's new findings may impact the biotechnology and automotive industries. [ABSTRACT FROM AUTHOR]

Artists often need to reshape 3D models of human-made objects by changing the relative proportions or scales of different model parts or elements while preserving the look and structure of the inputs. Manually reshaping inputs to satisfy these criteria is highly time-consuming; the edit in our teaser took an artist 5 hours to complete. However, existing methods for 3D shape editing are largely designed for other tasks and produce undesirable outputs when repurposed for reshaping. Prior work on 2D curve network reshaping suggests that in 2D settings the user-expected outcome is achieved when the reshaping edit keeps the orientations of the different model elements and when these elements scale as-locally-uniformly-as-possible (ALUP). However, our observations suggest that in 3D viewers are tolerant of non-uniform tangential scaling if and when this scaling preserves slippage and reduces changes in element size, or scale, relative to the input. Slippage preservation requires surfaces which are locally slippable with respect to a given rigid motion to retain this property post-reshaping (a motion is slippable if when applied to the surface, it slides the surface along itself without gaps). We build on these observations by first extending the 2D ALUP framework to 3D and then modifying it to allow non-uniform scaling while promoting slippage and scale preservation. Our 3D ALUP extension produces reshaped outputs better aligned with viewer expectations than prior alternatives; our slippage-aware method further improves the outcome producing results on par with manual reshaping ones. Our method does not require any user input beyond specifying control handles and their target locations. We validate our method by applying it to over one hundred diverse inputs and by comparing our results to those generated by alternative approaches and manually. Comparative study participants preferred our outputs over the best performing traditional deformation method by a 65% margin and over our 3D ALUP extension by a 61% margin; they judged our outputs as at least on par with manually produced ones. [ABSTRACT FROM AUTHOR]

Huntington's disease (HD) is a genetic disorder caused by a CAG trinucleotide expansion in the huntingtin (HTT) gene. Juan de Acosta, Atlántico, a city located on the Caribbean coast of Colombia, is home to the world's second-largest HD pedigree. Here, we include 291 descendants of this pedigree with at least one family member with HD. Blood samples were collected, and genomic DNA was extracted. We quantified the HTT CAG expansion using an amplicon sequencing protocol. The genetic heterogeneity was measured as the ratio of the mosaicism allele's read peak and the slippage ratio of the allele's read peak from our sequence data. The statistical and bioinformatic analyses were performed with a significance threshold of p < 0.05. We found that the average HTT CAG repeat length in all participants was 21.91 (SD = 8.92). Of the 291 participants, 33 (11.3%, 18 females) had a positive molecular diagnosis for HD. Most affected individuals were adults, and the most common primary and secondary alleles were 17/7 (CAG/CCG) and 17/10 (CAG/CCG), respectively. The mosaicism increased with age in the participants with HD, while the slippage analyses revealed differences by the HD allele type only for the secondary allele. The slippage tended to increase with the HTT CAG repeat length in the participants with HD, but the increase was not statistically significant. This study analyzed the genetic and molecular features of 291 participants, including 33 with HD. We found that the mosaicism increased with age in the participants with HD, particularly for the secondary allele. The most common haplotype was 17/7_17/10. The slippage for the secondary allele varied by the HD allele type, but there was no significant difference in the slippage by sex. Our findings offer valuable insights into HD and could have implications for future research and clinical management. [ABSTRACT FROM AUTHOR]

This study introduces a method based on fine torque control to evaluate traction in rolling—liding line contacts under small slide-to-roll ratios (SRRs). To accomplish this, we engineered an innovative testing machine—a two-roller tribometer capable of precisely applying resisting torques to one of the rollers. Two types of tests were designed and conducted to validate our method and showcase the capabilities of the novel test setup. The first type, named the "Traction Decay Test", proved to be effective in evaluating changes in the SRR over time. The second, named the "Torque-Mode Traction Test", demonstrated its effectiveness in achieving ultra-low SRRs, in the order of 0.01%. As a result, traction curves with high resolution in the low SRR domain were constructed. This advancement provides the means for gaining a deeper understanding of traction coefficients, wear behavior, and tribological performance at ultra-low SRRs across diverse applications. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Textile Technology is the property of Zhejiang Sci-Tech University Magazines and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Composite nanofibers have been widely investigated in aerospace, new energy, and biomedical fields, and the preparation method of them has become a hot research topic. Centrifugal spinning to prepare composite nanofibers is a neoteric pattern. In high-speed centrifugal composite spinning, the slippage theory of the two polymer solutions in the micro-triangle area has been analyzed, and the flow of the polymer solution in the micro-triangle area can further verify the occurrence of the slip motion in the micro-triangle area. It can be found that the rotational speed has the greatest effect on the preparation of composite nanofibers. When the rotational speed continues to increase, the slippage in the micro-triangle region occurs first with liquid-wall slippage, then with liquid–liquid interface slippage and finally with gas–liquid interface slippage. At the same rotational speed, the higher the concentration, the more concentrated the velocity distribution, and the better the prepared composite nanofiber structure. Finally, the optimal parameters for the preparation of PA composite nanofibers were obtained through the centrifugal composite spinning test. It provides theoretical and data support for centrifugal composite spinning micro-triangle slip and composite nanofibers preparation. [ABSTRACT FROM AUTHOR]

Background Purpose Discussion Conclusion For over two decades, the Queensland Curriculum and Assessment Authority (QCAA) has used Arnold’s tri-dimensional perspective of movement (1979, 1988) as a framework for its senior Physical Education (PE) syllabus documents (1998, 2004, 2010, and 2018). As the most recent version, the Queensland Senior Physical Education Syllabus-2019 (QSPES) cites Arnold’s perspective as ‘a philosophical and educative framework to promote deep learning in three dimensions: about, through and in movement contexts’ (QCAA 2018, 1), it is reasoned these principles will be evident throughout this Australian state syllabus.The purpose of this paper is to examine the claimed adherence to the Arnoldian perspective in the QSPES (QCAA 2018) as stated in its curriculum intention statement (see QCAA 2018, 1).The authors suggest that a reinterpretation of Arnold’s intention has occurred in the application of his perspective to the QSPES (QCAA 2018) and suggest what may occur as a consequence of this reinterpretation.We conclude by discussing the potential effects of this reoriented view of Arnold’s perspective on students, teachers, and PE in general. The discussion highlights a familiar story of PE attempting to legitimise itself through science and academia and how in most cases the warnings against such validation have fallen on deaf ears. [ABSTRACT FROM AUTHOR]

We report a case of postoperative slippage of a titanium clip that was used for a small ruptured anterior communicating artery aneurysm. Clipping was successful with no remnant in the initial operation. Progressive slippage of the clip was observed in follow-up brain computed tomography angiography studies. Digital subtraction angiography confirmed this finding. Reoperation was performed 19 days after the initial craniotomy. The clinical course after reoperation was uneventful. [ABSTRACT FROM AUTHOR]

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Introduction: Laparoscopic BariClip gastroplasty (LBCG) is a new reversible gastric sleeve-like procedure without gastrectomy proposed to minimize the risk of severe complications. Still one of the possible complications described with LBCG is slippage. The purpose of the current manuscript is to analyze different cases of slippage and propose a classification of this complication. Methods: A number of 381 patients who underwent LBCG in 8 different centers were analyzed concerning the risk of slippage. All cases with documented slippage were carefully reviewed in terms of patients' symptomatology (presence of satiety, vomiting), history of weight loss, radiological data, and management of their slippage. A new classification was proposed depending on the anatomy, the symptomatology, and the time of occurrence. Results: We have identified a total of 17 cases (4.46%) of slippage following LBCG. In 11 patients, the slippage was symptomatic with repetitive vomiting and nausea, and in the remaining 6 patients, the slippage was identified by radiological studies for insufficient weight loss, weight regain, or routine radiological follow-up. Depending on the interval time, the slippage was classified as either immediate (in first 7 days) in 6 cases, early (in less than 90 days) in 4 cases, and late (after 3 months) in 7 cases. Evaluation of the radiological studies in these cases identified the following: anterosuperior displacement (type A) in 9 cases, posteroinferior displacement (type B) in 6 cases (one case after 3 months), and lateral displacement (type C) in the remaining 2 cases. The management of the slippage consisted of BariClip removal in 7 cases, repositioning in 5 cases, and conservative treatment in the remaining 5 cases. All patients with conservative treatment were recorded at the beginning of the experience. Conclusions: Slippage is a possible complication after LBCG. This classification of the different types of slippage can benefit the surgeon in the management and treatment of this complication of LBCG. [ABSTRACT FROM AUTHOR]

Abstract The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process windows. Within this work, an effort is made to closely investigate and understand the process limits caused by excessive slippage of the workpiece. Optical measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process limit. Large differences in slippage were observed, depending on the tribological system. While systems with polymer based lubricants showed excessive slippage at low stroke rates, systems using oil or no lubricant endured higher stroke rates before process limits were reached. The optical measurements revealed three major forms of slippage: successful rolling without slippage, failure due to excessive slippage at process start, and failure due to excessive slippage at around one workpiece rotation.

Grouting after pouring aggregate can effectively control water inrush from coal and rock mass. The study on the deposition and migration law of aggregate in the water inrush channel from coal and rock mass is an important prerequisite to determine the aggregate particle size, aggregate grouting volume and the spacing of aggregate grouting holes. However, there are few theoretical and experimental studies in this area at present, and the actual construction mainly depends on experience, which is blind. In view of this, based on the slurry pipeline transportation theory and sediment movement mechanics, combined with Newton’s second law, the whole movement process of aggregate from the pouring hole to the water inrush channel is divided into three movement stages: free fall, similar horizontal throwing and sliding, and their stress analysis is carried out respectively. A sedimentation, migration and diffusion model from single aggregate to aggregate particle group is established, and the sedimentation and migration rules characterizing the aggregate particle group in the horizontal direction are obtained; A model test platform for visualization of aggregate deposition and movement in water inrush channel of coal and rock mass is designed by ourselves. With the help of this platform, aggregate deposition and movement model tests are carried out under the influence of various factors such as different hydrodynamic velocity, aggregate particle size, pouring height, et al, to analyze the deposition and movement rules of aggregates in water inrush channel, and to obtain the total length of aggregate deposition and movement area under different test schemes. The experimental results show that the actual migration process of aggregate is consistent with the assumption of three movement stages in theory, and the average error between the experimental value and the theoretical calculation value of the sediment migration distance of aggregate is 7.34%; On the premise that the injection height is controlled to be consistent with the dynamic water conditions, the theoretical formula is more applicable to coarse aggregate (particle size > 5 mm) than to fine aggregate (particle size ≤ 5 mm); When solving the problem of water inrush from coal and rock mass in engineering, if the aggregate particle size is greater than 5 mm, the migration distance of aggregate particle group in the horizontal direction can be calculated by using the theoretical formula in this paper, so as to determine the spacing of aggregate grouting holes and reduce the blindness in the actual construction process.

In 2007, the American Iron and Steel Institute (AISI) established a standard for cold-formed steel–special bolted moment frames (CFS-SBMFs). This structural system is designed to resist seismic forces. The CFS-SBMF system employs double-channel beams and square hollow structural section (HSS) columns that are bolted together to create a sturdy and robust structural frame. However, the CFS-SBMF system is only suitable for constructing one-storey buildings, and ASCE 7 prohibits its use in buildings with a height of over one storey. This study was conducted to expand the use of CFS-SBMFs to the construction of multi-storey low-rise buildings. Firstly, a new moment connection detail is proposed, and a design procedure is proposed to ensure that bolted connections, instead of beams or columns, have the ductility to withstand seismic forces. Secondly, the proposed design procedure for bolted connections was verified through full-scale cyclic testing. Finally, a comprehensive evaluation was undertaken to evaluate the proposed structural system’s performance under seismic excitation. The evaluation included nonlinear dynamic analysis and incremental dynamic analysis (IDA) according to FEMA P695, which provided a detailed understanding of the seismic design factors (SDFs) in multi-storey low-rise CFS-SBMF buildings.

The unbonded flexible riser has been increasingly applied in the ocean engineering industry to transport oil and gas resources from the seabed to offshore platforms. The slippage of helical layers, especially the tensile armor layers of unbonded flexible risers, contribute to the nonlinear hysteresis phenomenon, which is a research hotspot and difficulty. In this paper, on the basis of a typical eight-layer unbonded flexible riser model, the nonlinear slippage of a tensile armor layer and the corresponding nonlinear behavior of an unbonded flexible riser subjected to irregular external loads are studied by numerical modeling with detailed cross-sectional properties of the helical layers, and are verified through a theoretical method considering the coupled effect of the external loads on the unbonded flexible riser. Firstly, the balance equation of each layer considering the effect of external loads is established based on functional principles, and the overall theoretical model of the unbonded flexible riser is set up in consideration of the contact between adjacent layers. Secondly, the numerical modeling of each separate layer within the unbonded flexible riser, including the actual geometry of the carcass and pressure armor layer, is established, and solid elements are applied to all the interlayers, thus simulating the nonlinear contact and friction between and within interlayers. Finally, after verification through test data, the behavior of the unbonded flexible riser under the cyclic axial force, torsion, bending moment, and irregular external and internal pressure is studied. The results show that the tensile armor layer can slip under irregular loads. Additionally, some suggestions related to the analysis of unbonded flexible risers under irregular loads are drawn in the end.

The Swachh Bharat Mission-Rural (SBM-R) is a flagship programme aimed at ending open defecation in rural India. In this paper, we study institutions and processes using Amartya Sen's conception of justice. We review the outcomes by assessing agencies, actions and processes involved in the implementation of the SBM-R programme. The findings are analysed using the Sanitation Well-being Framework. Sanitation well-being is achieved when an individual is able to experience the sanitation life cycle stages of acceptance, construction, utilisation and maintenance of safe disposal, which are part of the framework. The capability factors grouped under personal, cultural, structural, environmental and service elements of the framework determine the sanitation environment facilitated by the state. Failure in experiencing one of the life stages leads to slippage in sanitation, where people resume open defecation, despite possessing toilets. The paper presents a review of literature on the political, technological and structural issues in programme implementation, followed by an analysis of 42 interviews and 12 focused group discussions of state and non-state actors conducted in rural Shravasti, Uttar Pradesh, India. We found that slippage is prevalent in the field site and identified 26 capability factors (expansion and constraints) that led to slippage in sanitation. HIGHLIGHTS Presents the institutional analysis of SBM-R implementation based on the perceptions of state and non-state actors.; Applied the Sanitation Well-being Framework to assess the sanitation environment by the state.; Slippage emerges as manifested injustice across personal, cultural, environmental, structural and service factors.; The factors have overlapping impacts on the sanitation life cycle stages influencing sanitation well-being.;

The creeping rotational motion of a magnetohydrodynamic couple stress fluid between two concentric spheres under the impact of slippages. The slippage conditions are applied on the surface of the inside sphere. In addition, the couple stresses on the boundary are assumed to vanish. The analytical solution to the problem is used to obtain the field functions of velocity, tangential stress, and couple stresses. The wall correction factor experienced by the fluid on the inner solid sphere is evaluated and plotted. However, in the presence of a magnetic field, the eddy current caused by rotating particles produces a torque that tends to rise because the assumption of the torque direction is the opposite direction of magnetic induction. Also, the first couple stress parameter, the angular velocity ratio, and slip condition did an improvement in the torque. On the other side, the wall correction factor slows down with slippage on the inner sphere and the size parameter. All results give limiting cases with no slippage and viscous fluid.

Aim: Slipped capital femoral epiphyisis (SCFE) is a common pathology requiring immediate surgical intervention. This study aims to assess the clinical and radiological midterm outcomes of SCFE patients fixed with a single cannulated screw. Materials and Methods: We examined 7 hips of 6 patients treated with SCFE and evaluated mid-term results in our study. Medical records and radiographs were reviewed for slip characteristics. SCFE cases were classified as stable or unstable, and stability was confirmed by perioperative scopy. For clinical evaluation, the Heyman-Herndon classification was utilized. All patients underwent surgical treatment on a traction table while under general anesthesia. Results: The average degree of slippage was 41.4 (27-67) and the average body mass index was 26.9 (25.4-29.4). The mean duration of follow-up was 16 months (range: 13-31 months). İn the follow-up, shortness and limping were in no way observed. The comparative radiographs of the patients revealed no subchondral cyst, osteophytic formation, or subchondral sclerosis. In all patients, the range of motion in the operated hip was normal. Conclusion: Osteosynthesis with a single screw in the current position or after a slight reduction to be an adequate treatment for SCFE requiring emergency surgery. [ABSTRACT FROM AUTHOR]

Coal bump seriously threatens the safe and efficient mining of coal, and the research on the occurrence mechanism of coal bump is of great significance. The roadway coal bump accounts for 86.8% of the total. The occurrence of coal bump in gateroad is summarized. It is considered that hard roof and hard coal are the geological characteristics of coal bump, and the sliding instability of rib coal mass is the failure characteristics of coal bump. Based on the elastic foundation theory, the upward deflection characteristics of the front and lateral roof of the working face under the condition of hard roof are analyzed, and compared with the engineering practice of roof rebounding. Taking the roadway coal mass as the research object, the unloading sliding mechanical model of roof-coal-floor composite structure is established. By analyzing the relationship between horizontal ground stress of coal mass, frictional force of coal-roof and coal-floor and tensile resistance of coal mass, the critical equation of coal bump is established. It is proposed that the vertical pressure of coal seam is reduced due to the upward deflection of the roof, and the coal mass loses its clamping and moves into the roadway after overcoming the friction between roof and floor and the tensile strength of coal mass under the action of horizontal ground stress, that is, the unloading and slippage mechanism of coal bump in hard roof mining roadway. The model reasonably explains the causality of coal bump in hard roof mining roadway. Based on the unloading-slippage model, the principle of influencing factors of coal bump, includes the buried depth, roof strength, roof elastic modulus and roof thickness, coal mass strength and elastic modulus. Finally, two coal bump events, "8.2" coal bump in Tangshan coal mine and "11.11" coal bump in Hongyang mine are analyzed and the unloading-slippage mechanism are the reasoning of two events. [ABSTRACT FROM AUTHOR]

This overview examines the results of a study of the effect of slippage in high-pressure torsion (HPT). A number of papers in this area and the works of the authors of this overview are considered. The authors used the method of the "joint HPT of the disk halves". This method is the simplest and most illustrative method for evaluating slippage during HPT. The authors used 10 and 20 mm diameter anvils, with a groove on the lower anvil and a calculated pressure of 6 GPa. In the case of the HPT of solid bulk metal glass (BMG), slippage starts at the early stages of HPT and is total. Slippage may also be significant at the early stages of the HPT of such metallic materials as Ti, Ni, Fe-0.1%C, and Zr-2.5%Nb. Slippage increases with the number of revolutions, n. There is no slippage at the initial stages of the HPT of copper. However, after HPT Cu n = 10, slippage can be total. Nevertheless, studies show that the structure of samples using HPT, obtained by the authors, is similar to the nanostructure observed by other authors after using HPT with similar materials. Thus, notwithstanding slippage during HPT, deformation during HPT still occurs, and nanostructure formation occurs. Therefore, the formation of a nanostructure in samples during HPT is not proof of the absence of slippage. The authors provide a possible explanation for this. The authors propose a new method—"accumulative high-pressure torsion"—to achieve a high strain in various materials. In this procedure, several cycles are repeated, according to the following scheme: "HPT for n = 1 or 2 turns of the anvil → cutting the specimen into pieces → unstacking the stacked pieces on the anvil and subsequent HPT for n = 1 or 2". Studies performed on a number of materials demonstrate that novel method transforms the structure more efficiently than regular HPT. [ABSTRACT FROM AUTHOR]

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