Search Results (106)

Upon reaching stabilized production in waterflooded reservoirs, waterflood performance curves are conventionally used to predict technically recoverable reserves (TRRs). However, as reservoirs enter high water-cut stages, the relationship between the relative permeability ratio and saturation becomes nonlinear, causing deflection in waterflood performance curves. This leads to systematic overestimation of both predicted TRR and ultimate recovery factors. To overcome these limitations in conventional TRR prediction methods, this study establishes a novel relative permeability ratio-saturation relationship based on characteristic relative permeability curve behaviors. The proposed model is validated for three distinct fluid-rock interaction types. We further develop a permeability-driven forecasting model for oil production rates and water cuts. Comparative analyses with a conventional waterflood curve methodology demonstrate significant accuracy improvements. The results show that while traditional methods predict TRR ranging from 78.40 to 92.29 million tons, our model yields 70.73 million tons—effectively resolving overestimation issues caused by curve deflection during high water-cut phases. This approach establishes a robust framework for determining critical development parameters, including economic field lifespan, strategy adjustments, and ultimate recovery factor. Full article

Cardiogenic shock (CS) in the setting of severe aortic stenosis (AS) presents a critical and high-risk scenario with limited therapeutic options and poor prognosis. Transcatheter aortic valve implantation (TAVI), initially reserved for inoperable or high-risk surgical candidates, is increasingly being considered in patients with CS due to improvements in device technology, operator experience, and supportive care. This review synthesizes current evidence from large registries, observational studies, and meta-analyses that support the feasibility, safety, and potential survival benefit of urgent or emergent TAVI in selected CS patients. Procedural success is high, and early intervention appears to confer improved short-term and mid-term outcomes compared to balloon aortic valvuloplasty or medical therapy alone. Critical factors influencing prognosis include lactate levels, left ventricular ejection fraction, renal function, and timing of intervention. The absence of formal guidelines, logistical constraints, and ethical concerns complicate decision-making in this unstable population. A multidisciplinary Heart Team/Shock Team approach is essential to identify appropriate candidates, manage procedural risk, and guide post-intervention care. Further studies and the development of TAVI-specific risk models in CS are anticipated to refine patient selection and therapeutic strategies. TAVI may represent a transformative option for stabilizing hemodynamics and improving outcomes in this otherwise high-mortality group. Full article

When the economy grows, people become wealthier and more autonomous from their intimate partners. This autonomy potentially has a negative impact on relationship stability: As per capita income increases, so does the divorce rate. Nevertheless, there is evidence that, after a certain income level, the divorce rate starts to decline, suggesting that the relationship between the two factors is not linear. The purpose of the current research is to examine the relationship between per capita income and divorce rate by analyzing historical data from the UK (obtained from the UK Office of National Statistics) and USA (obtained from the CDC and the Federal Reserve), as well as contemporary data encompassing a sample of 107 societies (obtained from the World Population Review and the World Bank). Our analysis finds a concave relationship between the two variables: an increase in per capita income corresponds to a rise in the divorce rate. However, beyond a certain threshold, the increase in per capita income is associated with a decrease in the divorce rate. Full article

Fragility fractures of the pelvis (FFPs) are common in elderly patients, particularly those with osteoporosis. FFPs can be associated with high mortality, morbidity, and functional decline. Known risk factors include being over 80 years old and delays in surgical intervention when this is required. While the role of surgery in FFPs remains less defined than in proximal femoral fractures in the elderly, studies indicate that surgical fixation offers improved survival and functional outcomes. Similarly, the choice of fixation method, whether posterior or anterior, and their combinations, vary between clinicians. It depends on the fracture type and patient-specific factors, such as bone quality and comorbidities, as well as the surgeon’s experience and the availability of resources. Additionally, orthobiologic adjuncts such as cement augmentation and sacroplasty can enhance the stability of an osteoporotic fracture during surgical intervention. Furthermore, medical treatments for osteoporosis, especially the use of teriparatide, have demonstrated beneficial effects in reducing fractures and promoting healing of the FFPs. Return to pre-injury activities is often limited, with independence rates remaining low at mid-term follow-up. Factors that influence clinical outcomes include fracture type, with Type III and IV fractures generally leading to poorer outcomes, and patient age, functional reserve, and comorbidities. The present tutorial aims to summarise the relevant evidence on all aspects of FFPs, inform an updated management strategy, and provide a template of the reconstruction ladder referring to the most available surgical techniques and treatment methods. Further research, based on large-scale studies, is needed to address the open questions described in this manuscript and refine surgical techniques, as well as determine optimal treatment pathways for this vulnerable patient population. Full article

Housing prices have recently risen sharply in many countries, primarily linked to the global credit cycle. Although various factors play a role, the ability of developing countries to navigate this cycle and maintain autonomous monetary policies is crucial. This paper introduces a dynamic macroeconomic model featuring a housing production sector within an imperfect banking framework. It captures key housing and economic dynamics in advanced and emerging economies. The analysis shows domestic liquidity policies, such as bank capital requirements, reserve ratios, and currency devaluation, can stabilize investment and production. However, their effectiveness depends on foreign interest rates and liquidity. Stabilizing housing prices and risk-free bonds is more effective in high-interest environments, while foreign liquidity shocks have asymmetric impacts. They can boost or lower the effectiveness of domestic policy, depending on the country’s level of financial development. These findings have several policy implications. For example, foreign capital controls would be adequate in the short term but not in the long term. Instead, governments would try to promote the development of local financial markets. Controlling debt should be a target for macroprudential policy as well as promoting saving instruments other than real estate, especially during low interest rates. Full article

The Qinghai–Tibet Plateau, a critical ecological barrier and major livestock region, faces deteriorating grasslands and rising forage demand under its harsh alpine climate. Oat (Avena sativa L.), valued for its cold tolerance, rapid biomass accumulation, and ability to thrive in nutrient-poor soils, can expand winter feed reserves and partly alleviate grazing pressure on native rangelands. However, genetic improvement alone has not been sufficient to address the environmental challenges. This issue is particularly severe in the Qaidam Basin, where soil salinization, characterized by high pH, poor soil structure, and low nutrient availability, significantly limits crop performance. Rhizosphere growth-promoting bacteria (PGPR) are environmentally friendly biofertilizers known to enhance crop growth, yield, and soil quality, but their application in the saline soil of the Qaidam Basin remains limited. We evaluated two PGPR application rates (B1 = 75 kg hm⁻² and B2 = 150 kg hm⁻²) on ‘Qingtian No. 1’ oat, assessing plant growth, soil physicochemical properties, and rhizosphere microbial communities. The results indicated that both treatments significantly increased oat productivity, raised the comprehensive growth index, augmented soil organic matter, and lowered soil pH; B1 chiefly enhanced above-ground biomass and fungal community stability, whereas B2 more strongly promoted root development and bacterial community stability. Structural equation modeling showed that PGPR exerted direct effects on the comprehensive growth index and indirect effects through soil and microbial pathways, with soil properties contributing slightly more than microbial factors. Notably, rhizosphere organic matter, fungal β-diversity, and overall microbial community stability emerged as positive key drivers of the comprehensive growth index. These findings provide a theoretical basis for optimizing PGPR dosage in alpine forage systems and support the sustainable deployment of microbial fertilizers under saline soil conditions in the Qaidam Basin. Full article

Food security is a critical component of national security. Grain silos, as key infrastructure for food storage, must remain structurally resilient under seismic actions to ensure the stability of grain reserves. However, column-supported vertical-group silo structures are prone to spatial torsional effects during earthquakes due to eccentricities between the mass center and the stiffness center after grain loading, which can lead to serious structural damage or collapse. Based on this background, shaking table tests were conducted on a column-supported vertical-group silo structure as the research subject, with a scale ratio of 1/25 and in the 1 row × 3 column combination form. The dynamic response and spatial torsional effect of the structure under different grain storage conditions and seismic intensity effects were studied. To thoroughly analyze the factors influencing the spatial torsion in the structure, finite element–discrete element numerical analysis models of the structure were established based on experiments in Abaqus (6.14) software. The results indicate that in the column-supported vertical-group silo structure, the mass center of the group silo structure deviates from its center of rigidity after grain storage, resulting in significant and irregular spatial torsional effects under earthquake motion. The torsional displacement ratio and inter-story horizontal torsional angle of the structure gradually increased with an increase in the seismic intensity, reaching maximum values of 1.34 and 0.035 rad, respectively, when the peak acceleration input on the table was 0.4 g and under the full–full–empty storage condition. The effects of the void distribution, mass void ratio, and combination form of the group silo structure on the spatial torsional effect of the structure were studied to provide a scientific reference for the seismic design of column-supported silo structures for grain storage. Full article

This study focuses on Neogene red-bed soft rock tunnels in the Huicheng Basin, China. Through engineering geological investigation, remote wireless monitoring systems, and total station multi-parameter monitoring, the deformation characteristics of red-bed soft rock surrounding rock under high in situ stress environments and their influencing factors were systematically analyzed. The findings reveal that the surrounding rock deformation follows a three-stage evolutionary pattern of “rapid, slow, and stable”. Construction disturbances can disrupt the stable state, leading to “deep V-shaped” anomalies or double-step responses in deformation curves. Spatially, the deformation exhibits significant anisotropy, with the haunch area showing the maximum deformation (95 mm) and the vault the minimum (65–73 mm). Deformation stabilization requires 30–42 days, and a reserved deformation of 10 cm is recommended based on specifications. Mechanical behavior analysis indicates that the stress–strain curves of red-bed argillaceous sandstone are stepped, with increased confining pressure enhancing both peak and residual strengths, validating the necessity of timely support. The study elucidates a multi-factor coupling mechanism: rock mass classification, temporal–spatial effects (excavation face constraints and rheological properties), construction methods, in situ stress levels, and support timing (timely support during the rapid phase inhibits strength degradation) significantly influence deformation evolution. The spatiotemporal distribution of surrounding rock pressure shows that invert pressure increases most rapidly, while vault pressure reaches the highest magnitude, with construction disturbances triggering stress redistribution. This research provides theoretical and practical guidance for the design, construction optimization, and disaster prevention of red-bed soft rock tunnels. Full article

Strip clearcutting and replanting are important methods for optimizing the structure of low-efficiency plantations, but their effects on soil aggregate properties remain unclear, especially in subtropical China, which experiences high levels of rainfall and high erosion risk. This study investigated changes in soil aggregate composition and stability through strip clearcutting and replanting treatments in Cunninghamia lanceolata plantations. The experimental treatments included clearcutting strips with widths of 10 m, 20 m, and 30 m and replanting with evergreen broadleaf Schima superba (SM10, SM20, and SM30) and deciduous broadleaf Liquidambar formosana (SF10, SF20, and SF30), respectively. The reserve belts were set at 15 m (S15), 30 m (S30), and 45 m (S45), with no clearcutting as the control (NT). The results indicated that soils of the treatment plots were dominated by >5 mm aggregates (57%–77%), however, lower than the control (NT) due to the clearcutting and replanting, except SF20 and S15 of reserve belts. The 20 m strip width with Liquidambar formosana replanting (SF20) demonstrated optimal soil structural stability, with significantly lower erodibility K values than the control. The content of >5 mm soil aggregates was significantly positively correlated with the mean weight diameter (MWD) and geometric mean diameter (GMD) and significantly negatively correlated with the erodibility factor (K). In contrast, the contents of the other particle sizes were significantly negatively correlated with the MWD and GMD and significantly positively correlated with the erodibility factor (K). This study demonstrates that 20 m strip clearcutting with Liquidambar formosana replanting (SF20) optimally maintains soil aggregate stability and reduces erosion risk, providing critical evidence for strip width configuration and species selection in ecological restoration of subtropical low-efficiency plantations. Full article

With the continuous change of climate, drought stress has emerged as the primary constraint on crop growth, posing a significant threat to the stability of global grain reserves. Arbuscular mycorrhizal fungi (AMF), as a kind of widely distributed root endophytes, enhance the drought tolerance of maize (Zea mays L.) through regulating the physiological and molecular responses. However, comprehensive transcriptome analysis to reveal the molecular mechanism of drought tolerance in the symbiotic process between AMF and maize is still limited. In the potted plant experiment, maizes inoculated with and without arbuscular mycorrhizal fungus Funneliformis mosseae were grown under well-watered (WW) or drought-stressed (DS) conditions. By using RNA-Seq and transcriptome analysis on maize roots and leaves, this work aimed to investigate the differential expressed genes (DEGs) related to the Ca²⁺ signaling pathway induced by AMF symbiosis under drought stress. Our findings indicated that F. mosseae inoculation resulted in a decrease in the net fluxes of Ca²⁺, while simultaneously elevating Ca²⁺ contents in the maize roots and leaves under well-watered or drought-stressed conditions. Notably, 189 DEGs were regulated not only by AMF symbiosis and drought stress, but also exhibited preferential expression in either leaves or roots. The annotation and enrichment of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) showed that most of the DEGs were significantly enriched in Ca²⁺ signaling pathway genes, related to signal transduction, cellular process, and defense response. A high number of DEGs with this function (including calcineurin B-like protein (CBL), CBL-interacting protein kinase (CIPK), mitogen-activated protein kinase (MAPK), and calcium-dependent protein kinase (CDPK) receptor kinases) were upregulated-DEGs or downregulated-DEGs in F. mosseae-inoculated maizes under drought stress. Furthermore, some DEGs belong to transcription factor (TF) families, including bHLH ERF, and, MYB, were speculated to play key roles in improving the drought tolerance of maize. Based on the expression data and co-expression analysis between TF and Ca²⁺ signaling pathway genes, Whirly1 with CBL11, and BRI1-EMS-SUPPRESSOR 1 (BES1) with CBL10, CIPK24, CDPK1, CDPK14, CDPK19, and MAPK9 genes showed significant positive correlations, while B3 domain-containing transcription factors (B3 TFs) with MAPK1 and both CBL9 genes showed significant negative correlations in response to both F. mosseae inoculation and drought stress. The regulation of Ca²⁺ signaling pathways by AMF symbiosis was an important response mechanism of maize to improve their drought resistance. This study provides insightful perspectives on how AMF-induced modulation of gene expression within the Ca²⁺ signaling pathway can enhance the drought tolerance of mycorrhizal maize in the future. Full article

Conducting research on the evaluation of rural resilience and risk governance strategies in the middle reaches of the Heihe River can provide a scientific basis for the sustainable development of rural areas in the inland river basins of arid regions. Affected by water resource constraints, the expansion of artificial oases, and excessive exploitation of groundwater, the rural areas in the middle reaches of the Heihe River Basin, the second largest inland river in the arid region of northwest China, are confronted with prominent contradictions in the human-land relationship and urgently need to enhance their ability to cope with risks. Based on the remote sensing data of land use and major socio-economic data, this study draws on the theory of landscape ecology to construct a disturbance-resistance-adaptability evaluation system. Taking Ganzhou District, a typical irrigated agricultural area, as a case study, the study uses the entropy weight method, resilience change rate, and obstacle degree model to analyze the rural resilience level and its changing characteristics from 1990 to 2020, identifies the key obstacle factors affecting the development of rural resilience, and proposes risk governance strategies accordingly. Main conclusions: (1) The overall rural resilience index is relatively low, showing significant spatial disparities. Towns with well-developed multifunctional agriculture, nature reserves, and ecological-cultural control lines have higher resilience indices. (2) The change rate of the rural resilience index demonstrates phase heterogeneity, generally undergoing a “relative stability-increase-decrease” process, and forming a differentiation pattern of “decrease in the north and increase in the south”. (3) Internal risks to rural resilience development in the Ganzhou District mainly stem from low economic efficiency, fragile ecological environment, and unstable landscape patterns, among which efficiency-dominant and landscape-stability obstacle factors have a broader impact scope, while habitat resistance-type obstacle factors are mainly concentrated in the western part and suburban areas. Enhancing the benefits of water and soil resource utilization, strengthening habitat resistance, and stabilizing landscape patterns are key strategies for current-stage rural resilience governance in the middle reaches of the Heihe River. This study aims to optimize the human-land relationship in the rural areas of the middle reaches of the Heihe River. Full article

Coalbed methane (CBM), a highly efficient and clean energy source with substantial reserves, holds significant development potential. Permeability is a crucial factor in CBM recovery in underground coal mines. Hydraulic fracturing technology causes water to enter the coal reservoir, which will change mechanical properties, affecting permeability changes and gas depletion trends. This study combines theoretical analysis with numerical simulation techniques to create a coupling model for fluid flow and reservoir deformation. The numerical model is established by referring to the geological conditions of the Wangpo coal mine, Shanxi province. Specifically, the impact of water immersion-induced softening and changes in the anisotropic mechanical properties on the directional permeability and gas flow rate is examined through parametric analysis. The dominant role in controlling the evolution of permeability varies depending on the orientation. Horizontal deformation primarily affects vertical permeability, which is subsequently influenced by the gas adsorption effect. In contrast, horizontal permeability is mainly determined by vertical deformation. Water immersion-induced softening significantly reduces the permeability and gas flow rate. Young’s modulus, which is dependent on water saturation, alters the permeability trend under water-rich conditions. Vertical permeability evolution is more sensitive to water-induced softening and changes in the anisotropic mechanical properties. When S_w0 is 0.7, the vertical permeability decreases by 60%, while the horizontal permeability decreases by 43%. Ultimately, the vertical permeability ratio stabilizes between 0.9 and 1.0, while the horizontal permeability ratio stabilizes in the range of 0.6 to 0.7. The influence of permeability on gas production characteristics is dependent on the water saturation conditions. In water-scarce conditions, variations in the fracture permeability greatly influence production flow rates. Conversely, in water-rich conditions, a higher permeability facilitates a quicker return to original levels and also enhances gas production flow rates. The research findings from this study provide important insights for fully understanding the mechanical properties of coal and ensuring the sustainable production of CBM. Full article

Neuroprotective strategies in coronary artery interventions are essential due to the rising number of high-risk patients undergoing procedures like coronary artery bypass grafting (CABG), totally endoscopic coronary artery bypass (TECAB), and hybrid revascularization. In this review article, we summarize the neurological complications associated with coronary artery disease intervention and the risk mitigation strategies. CABG carries significant risks, including ischemic stroke, encephalopathy, seizures, and peripheral nerve injuries. Risk factors include advanced age, hypertension, diabetes, and atherosclerosis. Off-pump CABG minimizes stroke risk by avoiding aortic manipulation and CPB. TECAB and hybrid revascularization have fewer reported neurological complications but still pose risks of stroke and cranial nerve injuries. Pharmacological neuroprotection includes agents such as barbiturates, volatile anesthetics, lidocaine, NMDA receptor antagonists, magnesium, nimodipine, corticosteroids, and aprotinin. Deep hypothermic circulatory arrest (DHCA) is reserved for complex aortic cases requiring a bloodless surgical field. Intraoperative strategies involve cerebral perfusion monitoring, embolic protection devices, and therapeutic hypothermia. Preoperative optimization targets risk factors, arrhythmia prevention, and antiplatelet therapy management. Postoperatively, timely antiplatelet administration, glucose control, hemodynamic stabilization, and cognitive monitoring are critical. Comprehensive neuroprotective approaches, spanning pre- to postoperative phases, aim to reduce neurological complications and enhance outcomes in coronary interventions. Full article

An isolated roof is an indispensable component of overlapping goaf. Focusing on the influence of dislocated width and width ratio on the stability of the isolated roof, this study analyzes the change rule of the safety factor of the roof supported by misaligned pillars and reveals the evolution characteristics of it by integrating numerical simulation into the strength reduction method. Firstly, with the increase of the dislocated width, the safety factor experienced three stages of sharp decrease, change from decrease to increase, and rapid increase. Secondly, the width ratio λ = 2 can be determined as the critical value of the safety reserve of the roof. In the interval λ ˂ 2, F decreases sharply with the increase of λ, but when λ ˃ 2, F decreases slowly and tends to 0. Thirdly, the overlap rate of pillars is a determinant of the type of damage but not of the safety factor of the roof. When η = 0, the safety factor is independent of the overlap rate. Furthermore, increasing the dislocated width can make the failure units accumulate continuously and then promote the plastic zone to expand gradually, resulting in roof collapse due to the penetration of the failure units. In this process, the tensile failure zone evolves from a single fold line to a wavy line, and the shear failure zone changes from a diagonal strip to a square strip. The study provides a new method to improve the stability of the roof, which is helpful to significantly reduce the collapse risk of overlapping goaf. Full article

Developmental dysplasia of the hip, particularly Crowe type IV, presents significant challenges in orthopedic surgery due to severe anatomical deformities and biomechanical instability. This study focuses on evaluating the biomechanical performance of a prosthesis–femur–derotation plate system designed to address these challenges. Using FEA, a comprehensive assessment of stress distribution, displacement, and safety factors was conducted under physiological loading conditions. The derotation plate was specifically engineered to stabilize the femur and restore the anatomical and biomechanical axis of the limb. Results demonstrated that the derotation plate effectively eliminated rotational and axial displacement, with a peak displacement of 0.08 mm, and maintained sufficient strength reserves, with a minimum safety factor of 3.63. The maximum von Mises stress in the plate was 76 MPa, significantly below the yield strength of the titanium alloy, ensuring long-term durability and reliability. The system as a whole exhibited favorable biomechanical properties, confirming its ability to manage high stress loads without the risk of material failure or instability. These findings underscore the potential of this novel system to improve surgical outcomes in complex cases of hip dysplasia. Future clinical trials will further validate its practical utility, providing valuable insights for advancing orthopedic implant design and patient care. Full article