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The development of bedding planes was a prominent feature of shale, and the stress interference between hydraulic fractures and bedding planes played a key role in forming fracture networks. Elucidation of the mechanism of the mutual interference between hydraulic fractures and bedding planes could help improve the fracturing technology of the shale fracture network. To simultaneously reflect the roles of both hydraulic fractures and bedding planes in the model, a series of large-size three-dimensional numerical models were established in this study using the ABAQUS finite element software. The cross-cohesive unit and the pipe flow unit were employed to simulate the cross-extension of the fracture with the bedding plane and the injection of fracturing fluid into the wellbore, respectively. Moreover, the correctness of the numerical models was verified by the analytical solution of the PKN simplified fracture model. The cohesive zone model (CZM) considered the softening effect and plastic zone at the top of cracks in quasibrittle rocks (e.g. shale), obtaining a more accurate crack geometry and in-seam pressure than linear elastic fracture mechanics. The cross-cohesive unit realized different traversal morphologies of the cracks when they interacted with the bedding plane. This paper analyzed the distribution of induced stresses generated by hydraulic fractures and bedding fractures. The induced stresses generated by hydraulic fractures were concentrated at the base of hydraulic fractures, and the stress shadows at the fracture tip made it easier for hydraulic cracks to cross bedding planes; the distribution plane of induced stresses generated by bedding fractures was parallel to bedding planes, and this induced stress was an essential factor influencing the traversal morphology of fractures. The results showed that the properties of the bedding plane significantly affected hydraulic fracture propagation in the height direction and the morphology of the fracture network. On the one hand, diverting the bedding plane limited the vertical propagation of hydraulic fractures. On the other hand, the induced stresses generated by the opened bedding plane hindered the opening of subsequent bedding planes.HighlightsA series of three-dimensional numerical models with multiple clusters and bedding planes considering the dynamic flow distribution and perforation friction were established.Considering the development of shale bedding, this paper focused on the influence of three bedding structural parameters, namely, bedding strength, bedding spacing and bedding density, on fracture propagation patterns.Both the interference mechanism between hydraulic fractures and bedding planes and between bedding planes themselves was revealed.

Extensive studies have been conducted on the rumination behavior of domestic herbivores. However, studies on wild animals are limited, particularly wild animals with specific ruminating parameters. In this study, Pere David's deer, a previously extirpated species, was observed to analyze the effects of sex-age, feeding habitat, and rainfall on rumination behavior in the Dafeng Nature Reserve, China. Rumination behavior was investigated based on four parameters: proportion of bedding time spent chewing, bolus processing time (s/bolus), chewing frequency (chews/bolus), and chewing rate (chews/s). Results showed that all three factors affect rumination behavior. The extent of their effects varied based on the four rumination parameters. Chewing rate and frequency decreased based on sex-age levels, i.e., from fawns to juvenile female, juvenile male, adult female, stag, and harem holder. Therefore, body size played a major role in shaping rumination behavior. Deer found in grasslands could chew faster compared with deer found in woodlands. This result might be caused by the effects of dietary composition and sunlight intensity. A deer spends a longer time ruminating while bedding during rainy days compared with rainless days to maximize energy and nutrition intake and compensate for the loss of feeding time during rainy days. Therefore, rumination behavior is plastic and is shaped by intrinsic and extrinsic factors.

BackgroundSurgery under general anesthesia results in temperature decrease due to the effect of anesthetics and peripheral vasodilation on thermoregulatory centers. Perioperative temperature control is therefore an issue of high importance. In this study, we aimed to compare the warming effect of underbody and overbody blankets in patients undergoing surgery in the lithotomy position under general anesthesia.MethodsFrom September 2018 to October 2019, 99 patients undergoing surgery for colorectal cancer in the lithotomy position were included in this randomized controlled trial and assigned to the intervention group (underbody blanket) or control group (overbody blanket).ResultsThe central temperature was significantly higher in the underbody blanket group than in the overbody blanket group at 90 min after the beginning of the surgery (p = 0.02); also in this group, the peripheral temperature was significantly higher 60 min after the beginning of the surgery (p = 0.02). Regarding postoperative factors, the underbody blanket group had a significantly lower frequency of postoperative shivering (p < 0.01) and a significantly shorter postoperative hospital stay (p = 0.04) than the overbody blanket group.ConclusionsWe recommend the use of underbody blankets for intraoperative temperature control in patients undergoing surgery in the lithotomy position under general anesthesia. Underbody blankets showed improved rise and maintenance of central and peripheral temperature, decreased the incidence of postoperative shivering, and shortened the postoperative length of hospital stay.

Sleep quality is an important issue of public concern. This study, combined with sensor application, aims to explore the determinants of perceived comfort when using smart bedding to provide empirical evidence for improving sleep quality. This study was conducted in a standard sleep laboratory in Quanzhou, China, from March to April of 2023. Perceived comfort was evaluated using the Subjective Lying Comfort Evaluation on a seven-point rating scale, and body pressure distribution was measured using a pressure sensor. Correlation analysis was employed to analyze the relationship between perceived comfort and body pressure, and multiple linear regression was used to identify the factors of perceived comfort. The results showed that body pressure was partially correlated with perceived comfort, and sleep posture significantly influenced perceived comfort. In addition, height, weight, and body mass index are common factors that influence comfort. The findings highlight the importance of optimizing the angular range of boards based on their comfort performance to adjust sleeping posture and equalize pressure distribution. Future research should consider aspects related to the special needs of different populations (such as height and weight), as well as whether users are elderly and whether they have particular diseases. The design optimization of the bed board division and mattress softness, based on traditional smart bedding, can improve comfort and its effectiveness in reducing health risks and enhancing health status.

Over half of US dairy operations use tie-stalls, but these farming systems have received relatively little research attention in terms of stall design and management. The current study tested the effects of the amount of 2 bedding materials, straw and shavings, on dairy cattle lying behavior. The effects of 4 levels of shavings, 3, 9, 15, and 24kg/stall (experiment 1, n=12), and high and low levels of straw in 2 separate experiments: 1, 3, 5, and 7kg/stall (experiment 2, n=12) and 0.5, 1, 2, and 3kg/stall (experiment 3, n=12) were assessed. Treatments were compared using a crossover design with lactating cows housed in tie-stalls fitted with mattresses. Treatments were applied for 1 wk. Total lying time, number of lying bouts, and the length of each lying bout was recorded with data loggers. In experiment 1, cows spent 3min more lying down for each additional kilogram of shavings (11.0, 11.7, 11.6, and 12.1±0.24 h/d for 3, 9, 15, and 24kg/stall shavings, respectively). In experiment 2, cows increased lying time by 12min for every additional kilogram of straw (11.2, 12.0, 11.8, and 12.4±0.24 h/d for 1, 3, 5, and 7kg/stall of straw, respectively). There were no differences in lying behavior among the lower levels of straw tested in experiment 3 (11.7±0.32 h/d). These results indicated that additional bedding above a scant amount improves cow comfort, as measured by lying time, likely because a well-bedded surface is more compressible.

In order to prevent the geological hazards of bedding landslides along the highway in mountainous areas, it is necessary to scientifically analyze the dynamic instability mechanism and the characteristics of the disaster-causing factors. On the basis of considering the effect of the retaining body, water pressure and compression deformation energy, a generalized chained regressive geomechanical model consisting of a slider, a lying soft rock and a retaining body was proposed, it also analyzed the four evolutionary stages of chained regressive phenomenon which included the initial stage of excavation, the middle stage of fracture development, the middle and late stage of system quasi-static deformation, and the stage of system instability before sliding. The stress field was derived by elastic theory. Based on the principle of energy conservation, the incremental balance equation of the generalized model was established, and the analytical formulas of the energy release curve and the energy dissipation curve, as well as the dynamic landslide starting slip force parameters were obtained. The method was applied to the landslide on national road 319 in Pengshui County, Chongqing city. Results illustrate: the generalized flexibility and generalized displacement are the control parameters for the dramatic instability of the slope. Energy accumulation, energy release curve and energy dissipation curve have two types: no intersection point and double intersection point. No intersection point corresponds to creeping slumping, and double intersection point corresponds to violent slumping. The contribution to the deformation energy accumulation is sorted from largest to smallest, followed by slider compression deformation energy, the function of the retaining body and the water pressure, among which the compression deformation energy of the slider cannot be ignored. The role of the retaining body has the dual effect of preventing sliding and increasing the deformation energy of the slider. The fissure water has a dual effect of hydrostatic pressure and erosion weakening effects. At the same time, the FLAC 3D finite difference method is used to verify the rationality of the theoretical model. The research results further explain the catastrophic law of the downhill chain regression model, reveal the disaster-causing efficiency of each influencing factor, it can provide a certain theoretical basis for the research and development of mountain road slope maintenance and disaster reduction technology.

Cows prefer to spend more time lying down in free stalls with more bedding, but no research to date has addressed the effects of bedding quality. Bedding in stalls often becomes wet either from exposure to the elements or from feces and urine. The aim of this study was to test the effect of wet bedding on stall preference and use. Four groups of 6 nonlactating Holstein cows were housed in free stalls bedded daily with approximately 0.1m of fresh sawdust. Following a 5-d adaptation period, each group of cows was tested sequentially with access to stalls with either dry or wet sawdust bedding (86.4±2.1 vs. 26.5±2.1% dry matter), each for 2 d. These no-choice phases were followed by a 2-d free-choice phase during which cows had simultaneous access to stalls containing either wet or dry bedding. Stall usage was assessed by using 24-h video recordings scanned at 10-min intervals, and responses were analyzed by using a mixed model, with group (n = 4) as the observational unit. The minimum and maximum environmental temperatures during the experiment were 3.4±2.2 and 6.8±2.5°C, respectively. When cows had access only to stalls with wet bedding, they spent 8.8±0.8 h/d lying down, which increased to 13.8±0.8 h/d when stalls with dry bedding were provided. Cows spent more time standing with their front 2 hooves in the stall when provided with wet vs. dry bedding (92±10 vs. 32±10 min/d). During the free-choice phase, all cows spent more time lying down in the dry stalls, spending 12.5±0.3 h/d in the dry stalls vs. 0.9±0.3 h/ d in stalls with wet bedding. In conclusion, dairy cows show a clear preference for a dry lying surface, and they spend much more time standing outside the stall when only wet bedding is available.

This study utilizes a service science perspective to elaborate on the strategic marketing plan of a Canadian mattress company. Founded in 2014, the company has transformed the mattress industry’s traditional product-centric paradigm by adopting a service-dominant logic and employing service systems thinking to fuel its competitive advantage. The research investigates how the company has incorporated concepts from service science, including value co-creation, customer involvement, and tailored solutions, into its marketing approach. The article highlights the importance of service science in developing strategic marketing approaches that work for creative, tech-driven companies by examining the company’s target market identification, marketing mix, and competitive positioning. The results offer valuable insights into the strategic use of service science in the contemporary, digitally-enabled marketplace for both scholars and practitioners.

The Nama Group, Namibia (≥550.5 to <538 million years ago, Ma), preserves one of the most diverse metazoan fossil records of the terminal Ediacaran Period. We report numerous features that may be biological in origin from the shallow marine, siliciclastic, lowermost Mara Member (older than ca. 550.5 Ma) from the Tsaus Mountains. These include forms that potentially represent body fossils, Beltanelliformis and an indeterminate juvenile uniterminal rangeomorph or arboreomorph frond, plug trace fossils, Bergaueria, as well as sedimentary surface textures, which are possibly microbially induced. These are the oldest documented macrofossils in the Nama Group. They represent taxa that persist from the Avalon or White Sea assemblages prior to the later appearance of new biota, including calcified metazoans, calcified and soft-bodied tubular taxa including all cloudinids, as well as more complex trace fossils. Using a new age model that allows more accurate stratigraphic placement of major Ediacaran macrofossil morphogroups and taxa, we propose a re-definition of the Nama Assemblage following the practice for Phanerozoic evolutionary faunas to include only new morphogroups of soft-bodied tubular, calcified taxa and complex trace fossils, defined by first appearance of Cloudina, which postdates deposition of the Kanies and lower Mara members and first appears ca. 550 Ma and persists until at least 539 Ma. Finally, the Tsaus Mountain environment is pristine, unspoilt by geologists and naturalists. Following World Heritage Convention, we suggest a pledge of non-destructive excavation that all future scientists should be able to make in publications of work that involve research in this area.