The 7 ka old Qixiangzhan lava flow(QXZ,Tianchi volcano)represents the last eruptive event before the 946 CE,caldera-forming‘Millennium’eruption(ME).Petrographic,whole rock,mineral composition,Sr-Nd isotopic data on ...The 7 ka old Qixiangzhan lava flow(QXZ,Tianchi volcano)represents the last eruptive event before the 946 CE,caldera-forming‘Millennium’eruption(ME).Petrographic,whole rock,mineral composition,Sr-Nd isotopic data on QXZ show that:(a)the lava consists of two components,constituted by comenditic obsidian fragments immersed in a continuous,aphanitic component;(b)both components have the same geochemical and isotopic variations of the ME magma.The QXZ and ME comendites result from fractional crystallization and crustal assimilation processes.The temperature of the QXZ magma was about 790℃ and the depth of the magma reservoir around 7 km,the same values as estimated for ME.QXZ had a viscosity of 10^(5.5)-10^(9) Pa s and a velocity of 3-10 km/yr.The emplacement time was 0.5-1.6yr and the flow rate 0.48-1.50 m^(3)/s.These values lie within the range estimated for other rhyolitic flows worldwide.The QXZ lava originated through a mixed explosive-effusive activity with the obsidian resulting from the ascent of undercooling,degassing and the fragmentation of magma along the conduit walls,whereas the aphanitic component testifies to the less undercooled and segregated flow at the center of the conduit.The QXZ lava demonstrates the extensive history of the ME magma chamber.展开更多
In this study,naringin was encapsulated in microspheres and its simulated digestive behavior in vitro was examined.Then naringin microspheres was added in yogurt to investigate the rheology and antioxidant activities....In this study,naringin was encapsulated in microspheres and its simulated digestive behavior in vitro was examined.Then naringin microspheres was added in yogurt to investigate the rheology and antioxidant activities.The results indicated that encapsulating naringin in microspheres delayed its digestion in the stomach,allowing more release in the intestinal part.All kinds of yogurt were solid-like in nature and the addition of microspheres increased the elastic modulus and viscosity.The naringin and microspheres incorporation enhanced the total phenolic content of the yogurt to 6.7 and 8.8 mg of gallic acid equivalent/mL,respectively.All kinds of yogurt demonstrated more than 80%scavenging ability for hydroxyl radicals at 20μL whey/mL.The addition of microspheres improved the DPPH radical scavenging ability of yogurt.This study provides a new idea for the application of polyphenols in food and the development of functional yogurt.展开更多
Cenozoic trachytes are characteristic of some active volcanic fields in China.In particular,the origin and mechanisms of the evolution of trachytes from the Tianchi(Changbaishan)volcano(TV,China/North Korea)are poorly...Cenozoic trachytes are characteristic of some active volcanic fields in China.In particular,the origin and mechanisms of the evolution of trachytes from the Tianchi(Changbaishan)volcano(TV,China/North Korea)are poorly known.Here,we present new geochronological,geochemical and isotopic data on two trachytic suites outcropping on the northern and southern upper slopes of TV.Detailed zircon laser ablation-multicollector-inductively coupled plasma-mass spectrometry(LA-MC-ICP-MS)U-Pb dating,Rb-Sr isochron dating of plagioclase and hornblende,^(40)Ar/^(39)Ar chronology with mineral chemistry,whole-rock element and Sr-Nd-Pb isotope data are used to explore their origins and evolutionary mechanisms during the late Middle Pleistocene.Our data indicate that the trachytes mainly consist of sanidine,orthoclase and plagioclase,with minor albite,quartz and hornblende.They formed at 0.353-0.346 Ma(lava flow from the northern slope)and 0.383-0.311 Ma(lava flow from the southern slope),respectively.The TV trachytes are characterized by high K_(2)O/Na_(2)O and AR values,with low A/CNK and Mg~#values.They are enriched in rare earth elements(REEs;except Eu),depleted in Sr and Ba,crystallizing at 742-858℃.The TV trachytes have high(^(87)Sr/^(86)Sr)_i values(0.70776-0.71195),positiveε_(Nd)(t)values(0.61-2.93)and radiogenic^(206)Pb/^(204)Pb values(17.515-17.806).These values are similar to those of the Pleistocene and Holocene TV trachytes.Geochemical data indicate that they were formed by fractional crystallization from a basaltic melt and assimilated upper crust material.The trace element pattern of the studied trachytes is consistent with an evolution from basaltic melts representative of an enriched mantle source.The vent from which the trachytic magma was erupted probably collapsed inside the caldera during the TV'Millennium'eruption(ME)in 946 AD.The contemporaneous emission of basaltic and trachytic magma during the Middle-Late Pleistocene suggests the coexistence of fissural basaltic volcanism and central-type trachytic volcanism,the latter of which was associated with a magma chamber in the upper crust during the TV cone-construction stage.展开更多
Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the po...Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the popular sulfur cathode.However,its practical application still faces great challenges,especially the rapid capacity decay triggered by the loss of active Se species.A comprehensive review to uncover the in-depth failure mechanism and provide targeted solutions to promote the stable operation of Li-Se batteries is urgently needed.This review systematically summarizes the strategies in the new perspective,focusing on the optimization of Se utilization in Li-Se batteries by keeping a high Se maintenance in the cathode and accelerating the electrochemical kinetics of lithium polyselenides(LiPSe)conversion.On the basis of stru ctural design and Li_(2)Se active material introduction to accommodate volume expansion,blocking s huttle transport of LiPSe by physical/chemical adsorption,bonding Se with polymers or cathode electrolyte interphase(CEI)construction,and catalytic design to accelerate the conversion of LiPSe,different strategies for improving the utilization of Se have been evaluated and discussed.To address the inevitable loss of Se,prospects on inactive Se reactivation and Li protection are detailedly proposed and analyzed referring to the chemistry and corrosion science.Additionally,the perspectives on the future design and comprehensive parameter evaluations for the optimization of Li-Se batteries are recommended.This review comprehensively explains the causes and solutions of capacity fading and provides potential efforts for lifespan expansion of batteries,shedding light on the future development of Li-Se batteries.展开更多
AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a popul...AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer （CRC）. METHODS： From April 2006 to April 2007, 43 290 individuals （age range 50-70） who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects （4.3%）. 1463 （77.7%） of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 （7.2%） were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep （polyethyleneglycole） in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values （PPV） were calculated. RESULTS： Twenty-one （50%） of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm. CONCLUSION： In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy.展开更多
It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several c...It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several causes of perinatal neurological injury and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of severe asphyxia. Sepsis, direct brain trauma, and drug or toxin exposure account for some cases, while mechanical forces of labor and delivery that increase fetal intracranial pressure sufficiently to impair brain perfusion may also contribute. Because of bony compliance and mobile suture lines, the fetal skull changes shape and redistributes cerebrospinal fluid during labor according to constraints imposed by contractions, and bony and soft tissue elements of the birth canal as the head descends. These accommodations, including the increase in intracranial pressure, are adaptive and necessary for efficient descent of the head while safeguarding cerebral blood flow. Autonomic reflexes mediated through central receptors normally provide ample protection of the brain from the considerable pressure exerted on the skull. On occasion, those forces, which are transmitted intracranially, may overcome the various adaptive anatomical, cardiovascular, metabolic, and neurological mechanisms that maintain cerebral perfusion and oxygen availability, resulting in ischemic brain injury. Accepting the notion of a potentially adverse impact of fetal head compression suggests that avoidance of excessive uterine activity and of relentless pushing without steady progress in descent may offer protection for the fetal brain during parturition. Excessive head compression should be considered in the differential diagnosis of ischemic encephalopathy.展开更多
With the beginning of the information systems’ spreading, people started thinking about using them for making business decisions. Computer technology solutions, such as the Decision Support System, make the decision-...With the beginning of the information systems’ spreading, people started thinking about using them for making business decisions. Computer technology solutions, such as the Decision Support System, make the decision-making process less complex and simpler for problem-solving. In order to make a high-quality business decision, managers need to have a great deal of appropriate information. Nonetheless, this complicates the process of making appropriate decisions. In a situation like that, the possibility of using DSS is quite logical. The aim of this paper is to find out the intended use of DSS for medium and large business organizations in USA by applying the Technology Acceptance Model (TAM). Different models were developed in order to understand and predict the use of information systems, but the information systems community mostly used TAM to ensure this issue. The purpose of the research model is to determine the elements of analysis that contribute to these results. The sample for the research consisted of the target group that was supposed to have completed an online questionnaire about the manager’s use of DSS in medium and large American companies. The information obtained from the questionnaires was analyzed through the SPSS statistical software. The research has indicated that, this is primarily used due to a significant level of Perceived usefulness and For the Perceived ease of use.展开更多
Introduction: Uniportal Video-Assisted Thoracic Surgery (U-VATS) has appeared as a promising, minimally invasive approach for thoracic oncology, offering benefits such as reduced trauma, shorter recovery times, and lo...Introduction: Uniportal Video-Assisted Thoracic Surgery (U-VATS) has appeared as a promising, minimally invasive approach for thoracic oncology, offering benefits such as reduced trauma, shorter recovery times, and lower complication rates. However, its adoption in resource-limited settings faces challenges, primarily due to limited access to specialized equipment, training, and infrastructure. Methods: This retrospective study evaluated the outcomes of 138 oncologic patients who underwent U-VATS between 2020 and 2024 at two centers in the Dominican Republic. Patients included those with primary lung cancer, pulmonary metastases, or masses requiring diagnostic biopsy. Data was extracted from patient records including epidemiological variables and clinical variables, treatments, and complications. A descriptive analysis was performed to summarize the data. Frequencies and percentages were calculated to report demographic and clinical characteristics, types of procedures, and postoperative outcomes. Results: The study population was predominantly middle-aged, with a near-equal gender distribution. Most patients underwent lung biopsies (63%), followed by lobectomies (22.5%) and metastasectomies (14.5%). The overall complication rate was low, with only 2.1% experiencing wound infections or atelectasis. The majority (87%) were discharged within 24 hours. These findings underscore U-VATS as a safe and effective choice for thoracic oncology in this setting. Conclusions: U-VATS shows promising outcomes in oncologic patients in the Dominican Republic, proving its feasibility and safety in a resource-limited environment. However, widespread adoption requires investment in infrastructure, training, and insurance coverage. Phased implementation, public-private partnerships, and cost-benefit analyses could support broader accessibility and integration of U-VATS, potentially improving patient outcomes and reducing healthcare costs in similar settings.展开更多
Blockchain technology holds significant promise for driving innovations across diverse industries, businesses, and applications. Recognized as a crucial source of competitive advantage in a fast-evolving environment, ...Blockchain technology holds significant promise for driving innovations across diverse industries, businesses, and applications. Recognized as a crucial source of competitive advantage in a fast-evolving environment, blockchain is anticipated to contribute substantially to sustainable economic and social development. Despite these high expectations, many blockchain projects currently face high failure rates, leading to negative impacts on various aspects of economic and social sustainability, including corporate governance, risk management, financial management, human resources, culture management, and competitiveness. This paper evaluates adoption models, identifying both risk and success factors. It introduces an integrated adoption model designed to operationalize, measure, and manage blockchain-driven business innovation sustainably. An empirical study involving 20 industry sectors and 125 business leaders was conducted to assess the model’s applicability. The findings indicate that the adoption model has the potential to support the sustainable implementation of blockchain technology for business innovations across various industries and applications. Future research and industry activities should continue validating this model through further case studies.展开更多
A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary...A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.展开更多
Information Technology or AI, a combination of computer science, logic, biology, psychology, and philosophy, is set to dominate our future, revolutionizing social progress, labor productivity, and cost reduction. It i...Information Technology or AI, a combination of computer science, logic, biology, psychology, and philosophy, is set to dominate our future, revolutionizing social progress, labor productivity, and cost reduction. It is essential for AI database integration and the next generation of computing, supporting Intelligent Information Systems and distributed cooperative labor. AI and IT integration are enhancing efficiency, creativity, and digital capabilities, with applications in customer service, healthcare, personalized medicine, and driverless cars. The paper tends to review the developments and trends in information technology using artificial intelligence (AI) as weapons to re-build the future world. With qualitative analysis of previous research studies, the paper tries to explain the role of AI in present information flow as well as for future. And after studying the selective papers it efficiently explains the advantage of AI in both human and environmental way. AI has the potential to significantly impact our lives, but fundamental questions remain unanswered about its extent, scope, and timeline. Current tools are insufficient to predict future AI achievements or fully comprehend its capabilities. To determine the readiness level for different technologies with AI, criteria are defined based on historical evolution. AI has revolutionized the IT industry, improving efficiency, productivity, and quality. However, concerns arise about the potential impact on the workforce, with concerns about job redundancy and potential unjust outcomes in critical areas like employment, finance, and law enforcement.展开更多
Objectives:Treatment of metastatic colorectal cancer(mCRC)includes resection of liver metastases(LM),however,no validated biomarker identifies patients most likely to benefit from this procedure.This meta-analysis aim...Objectives:Treatment of metastatic colorectal cancer(mCRC)includes resection of liver metastases(LM),however,no validated biomarker identifies patients most likely to benefit from this procedure.This meta-analysis aimed to assess the impact of the most relevant molecular alterations in cancer-related genes of CRC(i.e.,RAS,BRAF,SMAD4,PIK3CA)as prognostic markers of survival and disease recurrence in patients with mCRC surgically treated by LM resection.Methods:A systematic literature review was performed to identify studies reporting data regarding survival and/or recurrence in patients that underwent complete liver resection for CRC LM,stratified according to RAS,BRAF,PIK3CA,and SMAD4 mutational status.Hazard ratios(HRs)from multivariate analyses were pooled in the meta-analysis and various adjustment strategies for confounding factors were combined.The search was conducted in numerous databases,including MEDLINE(PubMed),Embase,Cumulative Index to Nursing and Allied Health Literature(CINAHL)(EBSCO host),and WHO Global Index Medicus,through March 18th,2022.Meta-analyses,editorials,letters to the editor,case reports,studies on other primary cancers,studies with primary metastatic sites other than the liver,studies lacking specific oncological outcome variables or genetic data,non-English language studies,and studies omitting residual disease data from liver metastasectomy were excluded.The remaining 47 studies were summarized in a descriptive table which outlines the key characteristics of each study and final results were graphically presented.Results:RAS mutation status was negatively associated with overall survival(OS)(HR,1.68;95%CI,1.54–1.84)and recurrence free survival(RFS)(HR,1.46;95%CI,1.33–1.61).A negative association was also found for BRAF regarding OS(HR,2.64;95%CI,2.15–3.24)and RFS(HR,1.89;95%CI,1.32–2.73)and SMAD4 regarding OS(HR,1.93;95%CI,1.56–2.38)and RFS(HR,1.95;95%CI,1.31–2.91).For PIK3CA only three studies were eligible and no significant association with either OS or RFS could be highlighted.Conclusion:RAS,BRAF,and SMAD4 are negatively associated with OS and RFS in patients undergoing curative liver metastasectomy from colorectal cancer.No conclusion can be drawn for PIK3CA due to the limited literature availability.These data support the integration of RAS,BRAF,and SMAD4 mutational status in the surgical decision-making for colorectal liver metastasis.Nevertheless,we have to consider several limitations,the major ones being the pooling of results from studies that evaluated patient outcomes as either disease-free survival(DFS)or RFS;the inclusion of patients with minimal residual disease and unconsidered potential confounding factors,such as variability in resectability definitions,chemotherapy use,and a potential interaction between biological markers and pre-and post-resection pharmacological treatments.展开更多
This study aims to examine the effect of replacing vanadium by niobium and iron on the tribological behavior of hot-isostatic-pressed titanium alloy （Ti-6Al-4V） biomaterial, using a ball-on-disk-type oscillating tri...This study aims to examine the effect of replacing vanadium by niobium and iron on the tribological behavior of hot-isostatic-pressed titanium alloy （Ti-6Al-4V） biomaterial, using a ball-on-disk-type oscillating tribometer, under wet conditions using physiological solution in accordance with the ISO7148 standards. The tests were carried out under a normal load of 6 N, with an AISI 52100 grade steel ball as a counter face. The morphological changes and structural evolution of the nanoparticle powders using different milling times （2, 6, 12 and 18 h） were studied. The morphological characterization indicated that the particle and crystallite size continuously decrease with increasing milling time to reach the lowest value of 4 nm at 18-h milling. The friction coefficient and wear rate were lower in the samples milled at 18 h （0.226, 0.297 and 0.423; and 0.66 × 10-2, 0.87 × 10-2 and 1.51 × 10-2 μm3 N-1 i, tm-1） for Ti-6Al-4Fe, Ti-6A1-7Nb and Ti-6Al-4V, respectively. This improvement in friction and wear resistance is attributed to the grain refinement at 18-h milling. The Ti-6Al-4Fe samples showed good tribological performance for all milling times.展开更多
In this article,we are concerned with analytical solutions for a model of inviscid liquid-gas two-phase flow.On the basis of Yuen’s works[25,27–29]on self-similar solutions for compressible Euler equations,we presen...In this article,we are concerned with analytical solutions for a model of inviscid liquid-gas two-phase flow.On the basis of Yuen’s works[25,27–29]on self-similar solutions for compressible Euler equations,we present some special self-similar solutions for a model of inviscid liquid-gas two-phase flow in radial symmetry with and without rotation,and in elliptic symmetry without rotation.Some blowup phenomena and the global existence of the solutions obtained are classified.展开更多
Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is gov...Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is governed by the flux properties and effective stress at that plane.At the failure plane,the pore water pressure was higher than the effective stress,and the volume change was the highest.The pore water pressure is a function of the soil profile features(particularly the phreatic zone width)and bedrock motion(horizontal acceleration).The volume change at the failure plane is a function of the intrinsic permeability of the soil and bedrock displacement.The failure plane was predicted to occur during the oscillation with the highest amplitude,disregarding further bedrock motion,which was consistent with low seismic energy densities.Two mechanisms were proposed to explain the persistence of soil liquefaction.The first is the existence of low-permeability layers in the depth range in which the failure planes are predicted to occur.The other allows for the persistence and development of soil liquefaction;it is consistent with homogeneous soils and requires water inflow from bedrock water springs.The latter explains many of the features of soil liquefaction observed during earthquakes,namely,surficial effects,“instant”liquefaction,and the occurrence of short-and long-term changes in the level of the phreatic surfaces.This model(hypothesis),the relationship between the flux characteristics and loss of soil shear strength,provides self-consistent constraints on the depth below the phreatic surfaces where the failure planes are observed(expected to occur).It requires further experimental and observational evidence.Similar reasoning can be used to explain other saturated soil phenomena.展开更多
Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and characterized.For some of them single crystals were obtained and their molecular structure was determined by X-ray ...Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and characterized.For some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction method.All the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar ratio.The behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.展开更多
In this paper,the Multi-Temporal Interferometric Synthetic Aperture Radar(MT-InSAR)technology is adopted to monitor the Line of Sight(LOS)displacement of Fushun West Opencast Coal Mine(FWOCM)and its surrounding areas ...In this paper,the Multi-Temporal Interferometric Synthetic Aperture Radar(MT-InSAR)technology is adopted to monitor the Line of Sight(LOS)displacement of Fushun West Opencast Coal Mine(FWOCM)and its surrounding areas in northeast China using Sentinel-1 Synthetic Aperture Radar(SAR)images acquired from 2018 to 2022.The spatial-temporal evolution of urban subsidence and the south-slope landslide are both analyzed in detail.Comparison with ground measurements and cross-correlation analysis via cross wavelet transform with monthly precipitation data are also conducted,to analyze the influence factors of displacements in FWOCM.The monitoring results show that a subsidence basin appeared in the urban area near the eastern part of the north slope in 2018,with settlement center located at the intersection of E3000 and fault F1.The Qian Tai Shan(QTS)landslide on the south slope,which experienced rapid sliding during 2014 to 2016,presents seasonal deceleration and acceleration with precipitation,with the maximum displacement in vicinity of the Liushan paleochannel.The results of this paper have fully taken in account for the complications of large topographic relief,geological conditions,spatial distribution and temporal evolution characteristics of surface displacements in opencast mining area.The wide range and long time series dynamic monitoring of opencast mine are of great significance to ensure mine safety production and geological disaster prevention in the investigated mining area.展开更多
Improving organizational performance can be achieved through business process redesign (BPR). When it comes to modern work practices, organizations must often redesign their processes to keep up. This is where enterpr...Improving organizational performance can be achieved through business process redesign (BPR). When it comes to modern work practices, organizations must often redesign their processes to keep up. This is where enterprise software comes in, offering a common data infrastructure that enables different parts of the organization to access all necessary financial data. The architecture of network accounting business process is divided into three layers. The core layer lies in the enterprise LAN that it can integrate six business processes information into one unity of financial information and non-financial information, including purchasing, inventory, production, sales, finance and customer service, and it can generate flexibly a variety of accounting statements to meet fully the information users’ demands by providing more complete and more valuable related information. The second layer lies in Intranet among enterprises based on the core layer that it can support the link of business processes and the inter-sharing of information among node enterprises of SCM and other external enterprises. The third layer lies in Internet based on the second layer that it can fit society, enterprise and individual together, the specific lays the solid foundation of business collaboration, remote management, online management and centralized management. The operating mechanisms of the network accounting business processes are as follows. When the business event occurs, the probe can get the event information in real-time and the result is stored in the database. Meanwhile, the drive controller can control the business events in real-time by gaining control criteria and standards from database. In case the standard is exceeded, the event is not allowed to occur. Enterprise’ business staff or external personnel can output automatically the required results through report tools if they had the reading authority. Supported the information system and optimizing processes, the managers can directly use the business event information, criteria and standards to control, guide, regulate and restrict management and operation in real-time, improving operation efficiency and effect. The enterprise can share the accounting information with node enterprises of SCM to bring about JIT that improve the core competitiveness of enterprise. This helps them to function more efficiently, cut costs, enhance customer service, and minimize the risk of human errors. Justifying projects has become increasingly crucial as information systems become more expensive and vital to organizations. IT can pursue two distinct goals: lowering operating costs or improving productivity, based on the difference between operational effectiveness and strategic positioning.展开更多
A thermoelectric generation Stirling engine (TEG-Stirling engine) is discussed by employing a low temperature Stirling engine and the dissipative equation of motion derived from the method of thermomechanical dynamics...A thermoelectric generation Stirling engine (TEG-Stirling engine) is discussed by employing a low temperature Stirling engine and the dissipative equation of motion derived from the method of thermomechanical dynamics (TMD). The results and mechanism of axial flux electromagnetic induction (AF-EMI) are applied to a low temperature Stirling engine, resulting in a TEG-Stirling engine. The method of TMD produced thermodynamically consistent and time-dependent physical quantities for the first time, such as internal energy ℰ(t), thermodynamic work Wth(t), the total entropy (heat dissipation) Qd(t)and measure or temperature of a nonequilibrium state T˜(t). The TMD analysis produced a lightweight mechanical system of TEG-Stirling engine which derives electric power from waste heat of temperature (40˚CT100˚C) by a thermoelectric conversion method. An optimal low rotational speed about 30θ′(t)/(2π)60(rpm) is found, applicable to devices for sustainable, clean energy technologies. The stability of a thermal state and angular rotations of TEG-Stirling engine are specifically shown by employing properties of nonequilibrium temperature T˜(t), which is also applied to study optimal fuel-injection and combustion timings of heat engines.展开更多
Background: Mobility in older adults can be impaired after acute illness or hospitalization, and the level of severity can be used as a predictor of one’s ability to return to independent living. Patients are often r...Background: Mobility in older adults can be impaired after acute illness or hospitalization, and the level of severity can be used as a predictor of one’s ability to return to independent living. Patients are often referred to skilled nursing facilities in hopes of improving their mobility. We wanted to prove that rehabilitative services at Skilled Nursing Facilities improve overall outcomes. Methods: We conducted a retrospective analysis of data from 4612 patients admitted for short-term rehabilitation in a large nursing home chain in California. Our aim was to determine whether patients’ mobility scores, as measured by rehabilitative staff, significantly improved by time of discharge compared to their scores at admission. Mobility scores were rated from 1 to 6, with 1 being the most dependent on aid and 6 being the most independent, over a variety of tasks at admission and compared to scores at discharge. Pearson’s correlations were performed to determine if there were significant relationships in the data: the Pearson’s correlation coefficient was used to describe the relationships between patient admission to a skilled nursing facility and medical improvement upon discharge. Results: The study demonstrated a statistically significant improvement in patients’ mobility scores upon discharge, with Medicare insured patients showing on average 57% improvement and Managed Care insured patients showing on average 59% improvement. Additionally, admission scores appeared to be predictive of the patient’s outcome at discharge. Conclusions: The values and consistency of improvement support the use of acute rehabilitative services in skilled nursing facilities. An equation can be formulated that evaluates patients’ estimated mobility statuses upon discharge from facilities based on their conditions on their arrivals. With this, new interventions can be studied and compared to the current standard of care by using these measurements. They can determine if further improvements can be made to increase patient outcomes.展开更多
基金funded by the National Natural Science Foundation of China(Grant Nos.41972313 and 41790453)the Engineering Research Center of Geothermal Resources Development Technology and Equipment,Ministry of Education,Jilin University。
文摘The 7 ka old Qixiangzhan lava flow(QXZ,Tianchi volcano)represents the last eruptive event before the 946 CE,caldera-forming‘Millennium’eruption(ME).Petrographic,whole rock,mineral composition,Sr-Nd isotopic data on QXZ show that:(a)the lava consists of two components,constituted by comenditic obsidian fragments immersed in a continuous,aphanitic component;(b)both components have the same geochemical and isotopic variations of the ME magma.The QXZ and ME comendites result from fractional crystallization and crustal assimilation processes.The temperature of the QXZ magma was about 790℃ and the depth of the magma reservoir around 7 km,the same values as estimated for ME.QXZ had a viscosity of 10^(5.5)-10^(9) Pa s and a velocity of 3-10 km/yr.The emplacement time was 0.5-1.6yr and the flow rate 0.48-1.50 m^(3)/s.These values lie within the range estimated for other rhyolitic flows worldwide.The QXZ lava originated through a mixed explosive-effusive activity with the obsidian resulting from the ascent of undercooling,degassing and the fragmentation of magma along the conduit walls,whereas the aphanitic component testifies to the less undercooled and segregated flow at the center of the conduit.The QXZ lava demonstrates the extensive history of the ME magma chamber.
基金funded by the People’s Livelihood Plan Project of Department of Science and Technology of Liaoning Province(2021JH2/10300069,2019-ZD-0845)the Department of Education of Liaoning Province(Natural Science,Strategic Industrialization Project,LJ212410163061)the Liaoning Province College Students Innovation and Entrepreneurship Training Program(S202410163077).
文摘In this study,naringin was encapsulated in microspheres and its simulated digestive behavior in vitro was examined.Then naringin microspheres was added in yogurt to investigate the rheology and antioxidant activities.The results indicated that encapsulating naringin in microspheres delayed its digestion in the stomach,allowing more release in the intestinal part.All kinds of yogurt were solid-like in nature and the addition of microspheres increased the elastic modulus and viscosity.The naringin and microspheres incorporation enhanced the total phenolic content of the yogurt to 6.7 and 8.8 mg of gallic acid equivalent/mL,respectively.All kinds of yogurt demonstrated more than 80%scavenging ability for hydroxyl radicals at 20μL whey/mL.The addition of microspheres improved the DPPH radical scavenging ability of yogurt.This study provides a new idea for the application of polyphenols in food and the development of functional yogurt.
基金financially supported by the project of the National Observation and Research Station of the Institute of Geology,China Earthquake Administration(Grant No.NORSCBS22-06)the Youth Science and Technology Development Project of the Jilin Earthquake Agency(Grant No.JZQ-202402)+1 种基金the Earthquake Science and Technology Spark Project(Grant No.XH23013B)the China Scholarship Council(Grant No.202104190014)。
文摘Cenozoic trachytes are characteristic of some active volcanic fields in China.In particular,the origin and mechanisms of the evolution of trachytes from the Tianchi(Changbaishan)volcano(TV,China/North Korea)are poorly known.Here,we present new geochronological,geochemical and isotopic data on two trachytic suites outcropping on the northern and southern upper slopes of TV.Detailed zircon laser ablation-multicollector-inductively coupled plasma-mass spectrometry(LA-MC-ICP-MS)U-Pb dating,Rb-Sr isochron dating of plagioclase and hornblende,^(40)Ar/^(39)Ar chronology with mineral chemistry,whole-rock element and Sr-Nd-Pb isotope data are used to explore their origins and evolutionary mechanisms during the late Middle Pleistocene.Our data indicate that the trachytes mainly consist of sanidine,orthoclase and plagioclase,with minor albite,quartz and hornblende.They formed at 0.353-0.346 Ma(lava flow from the northern slope)and 0.383-0.311 Ma(lava flow from the southern slope),respectively.The TV trachytes are characterized by high K_(2)O/Na_(2)O and AR values,with low A/CNK and Mg~#values.They are enriched in rare earth elements(REEs;except Eu),depleted in Sr and Ba,crystallizing at 742-858℃.The TV trachytes have high(^(87)Sr/^(86)Sr)_i values(0.70776-0.71195),positiveε_(Nd)(t)values(0.61-2.93)and radiogenic^(206)Pb/^(204)Pb values(17.515-17.806).These values are similar to those of the Pleistocene and Holocene TV trachytes.Geochemical data indicate that they were formed by fractional crystallization from a basaltic melt and assimilated upper crust material.The trace element pattern of the studied trachytes is consistent with an evolution from basaltic melts representative of an enriched mantle source.The vent from which the trachytic magma was erupted probably collapsed inside the caldera during the TV'Millennium'eruption(ME)in 946 AD.The contemporaneous emission of basaltic and trachytic magma during the Middle-Late Pleistocene suggests the coexistence of fissural basaltic volcanism and central-type trachytic volcanism,the latter of which was associated with a magma chamber in the upper crust during the TV cone-construction stage.
基金supported by the China Scholarship Council(No.201809370046)a scholarship from the Laboratory of Inorganic Materials Chemistry,Universitéde Namur+5 种基金the National Key R&D Program of China(2016YFA0202602)the National Natural Science Foundation of China(No.U1663225,22293020,22293022 and 52103342)the Program of Introducing Talents of Discipline to Universities-Plan 111(Grant No.B20002)from the Ministry of Science and Technologythe Program for Changjiang Scholars and Innovative Research Team in University(IRT_15R52)of the Chinese Ministry of EducationBelgium-China Governmental Key Cooperation Program WBI-MOST(SUB/2021/IND493971/524448)the“Plan of relance”Wallonia Government(2310153-Bat Factory)。
文摘Lithium-selenium(Li-Se)batteries have attracted increasing attention as one of the next-generation battery systems due to much higher electronic conductivity and comparable volumetric capacity of Se compared to the popular sulfur cathode.However,its practical application still faces great challenges,especially the rapid capacity decay triggered by the loss of active Se species.A comprehensive review to uncover the in-depth failure mechanism and provide targeted solutions to promote the stable operation of Li-Se batteries is urgently needed.This review systematically summarizes the strategies in the new perspective,focusing on the optimization of Se utilization in Li-Se batteries by keeping a high Se maintenance in the cathode and accelerating the electrochemical kinetics of lithium polyselenides(LiPSe)conversion.On the basis of stru ctural design and Li_(2)Se active material introduction to accommodate volume expansion,blocking s huttle transport of LiPSe by physical/chemical adsorption,bonding Se with polymers or cathode electrolyte interphase(CEI)construction,and catalytic design to accelerate the conversion of LiPSe,different strategies for improving the utilization of Se have been evaluated and discussed.To address the inevitable loss of Se,prospects on inactive Se reactivation and Li protection are detailedly proposed and analyzed referring to the chemistry and corrosion science.Additionally,the perspectives on the future design and comprehensive parameter evaluations for the optimization of Li-Se batteries are recommended.This review comprehensively explains the causes and solutions of capacity fading and provides potential efforts for lifespan expansion of batteries,shedding light on the future development of Li-Se batteries.
文摘AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer （CRC）. METHODS： From April 2006 to April 2007, 43 290 individuals （age range 50-70） who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects （4.3%）. 1463 （77.7%） of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 （7.2%） were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep （polyethyleneglycole） in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values （PPV） were calculated. RESULTS： Twenty-one （50%） of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm. CONCLUSION： In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy.
文摘It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several causes of perinatal neurological injury and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of severe asphyxia. Sepsis, direct brain trauma, and drug or toxin exposure account for some cases, while mechanical forces of labor and delivery that increase fetal intracranial pressure sufficiently to impair brain perfusion may also contribute. Because of bony compliance and mobile suture lines, the fetal skull changes shape and redistributes cerebrospinal fluid during labor according to constraints imposed by contractions, and bony and soft tissue elements of the birth canal as the head descends. These accommodations, including the increase in intracranial pressure, are adaptive and necessary for efficient descent of the head while safeguarding cerebral blood flow. Autonomic reflexes mediated through central receptors normally provide ample protection of the brain from the considerable pressure exerted on the skull. On occasion, those forces, which are transmitted intracranially, may overcome the various adaptive anatomical, cardiovascular, metabolic, and neurological mechanisms that maintain cerebral perfusion and oxygen availability, resulting in ischemic brain injury. Accepting the notion of a potentially adverse impact of fetal head compression suggests that avoidance of excessive uterine activity and of relentless pushing without steady progress in descent may offer protection for the fetal brain during parturition. Excessive head compression should be considered in the differential diagnosis of ischemic encephalopathy.
文摘With the beginning of the information systems’ spreading, people started thinking about using them for making business decisions. Computer technology solutions, such as the Decision Support System, make the decision-making process less complex and simpler for problem-solving. In order to make a high-quality business decision, managers need to have a great deal of appropriate information. Nonetheless, this complicates the process of making appropriate decisions. In a situation like that, the possibility of using DSS is quite logical. The aim of this paper is to find out the intended use of DSS for medium and large business organizations in USA by applying the Technology Acceptance Model (TAM). Different models were developed in order to understand and predict the use of information systems, but the information systems community mostly used TAM to ensure this issue. The purpose of the research model is to determine the elements of analysis that contribute to these results. The sample for the research consisted of the target group that was supposed to have completed an online questionnaire about the manager’s use of DSS in medium and large American companies. The information obtained from the questionnaires was analyzed through the SPSS statistical software. The research has indicated that, this is primarily used due to a significant level of Perceived usefulness and For the Perceived ease of use.
文摘Introduction: Uniportal Video-Assisted Thoracic Surgery (U-VATS) has appeared as a promising, minimally invasive approach for thoracic oncology, offering benefits such as reduced trauma, shorter recovery times, and lower complication rates. However, its adoption in resource-limited settings faces challenges, primarily due to limited access to specialized equipment, training, and infrastructure. Methods: This retrospective study evaluated the outcomes of 138 oncologic patients who underwent U-VATS between 2020 and 2024 at two centers in the Dominican Republic. Patients included those with primary lung cancer, pulmonary metastases, or masses requiring diagnostic biopsy. Data was extracted from patient records including epidemiological variables and clinical variables, treatments, and complications. A descriptive analysis was performed to summarize the data. Frequencies and percentages were calculated to report demographic and clinical characteristics, types of procedures, and postoperative outcomes. Results: The study population was predominantly middle-aged, with a near-equal gender distribution. Most patients underwent lung biopsies (63%), followed by lobectomies (22.5%) and metastasectomies (14.5%). The overall complication rate was low, with only 2.1% experiencing wound infections or atelectasis. The majority (87%) were discharged within 24 hours. These findings underscore U-VATS as a safe and effective choice for thoracic oncology in this setting. Conclusions: U-VATS shows promising outcomes in oncologic patients in the Dominican Republic, proving its feasibility and safety in a resource-limited environment. However, widespread adoption requires investment in infrastructure, training, and insurance coverage. Phased implementation, public-private partnerships, and cost-benefit analyses could support broader accessibility and integration of U-VATS, potentially improving patient outcomes and reducing healthcare costs in similar settings.
文摘Blockchain technology holds significant promise for driving innovations across diverse industries, businesses, and applications. Recognized as a crucial source of competitive advantage in a fast-evolving environment, blockchain is anticipated to contribute substantially to sustainable economic and social development. Despite these high expectations, many blockchain projects currently face high failure rates, leading to negative impacts on various aspects of economic and social sustainability, including corporate governance, risk management, financial management, human resources, culture management, and competitiveness. This paper evaluates adoption models, identifying both risk and success factors. It introduces an integrated adoption model designed to operationalize, measure, and manage blockchain-driven business innovation sustainably. An empirical study involving 20 industry sectors and 125 business leaders was conducted to assess the model’s applicability. The findings indicate that the adoption model has the potential to support the sustainable implementation of blockchain technology for business innovations across various industries and applications. Future research and industry activities should continue validating this model through further case studies.
文摘A metropolitan city such as Los Angeles (LA) is an ideal study site with a very high population density, and it houses at least 3 treatment plants where sewage is treated preliminarily and then progressing to tertiary treatment before discharging into the LA River. We will gain a better understanding of the water quality in the LA River and the nitrate load in the watershed system by examining the influence of waste water treatment plants (WWTPs). The goal of this study is to pinpoint the exact source of nitrate in the LA River using the isotope signatures. We have selected sampling locations both upstream and downstream of the WWTP. This serves to monitor nitrate levels, aiding in the assessment of treatment plant effectiveness, pinpointing nitrate pollution sources, and ensuring compliance with environmental regulations. The research explores the isotopic composition of NO3 in relation to atmospheric nitrogen and Vienna Standard Mean Ocean Water, shedding light on the contributions from various sources such as manure, sewage, soil organic nitrogen, and nitrogen fertilizers. Specifically, there is a change in the δ15NAir value between the dry and wet seasons. The isotope values in the Tillman WWTP sample changed between dry and wet seasons. Notably, the presence of nitrate originating from manure and sewage is consistent across seasons, emphasizing the significant impact of anthropogenic and agricultural activities on water quality. This investigation contributes to the broader understanding of nitrogen cycling in urban water bodies, particularly in the context of wastewater effluent discharge. The findings hold implications for water quality management and highlight the need for targeted interventions to mitigate the impact of nitrogen-containing compounds on aquatic ecosystems. Overall, the study provides a valuable framework for future research and environmental stewardship efforts aimed at preserving the health and sustainability of urban water resources. This data informs decisions regarding additional treatment or mitigation actions to safeguard downstream water quality and ecosystem health.
文摘Information Technology or AI, a combination of computer science, logic, biology, psychology, and philosophy, is set to dominate our future, revolutionizing social progress, labor productivity, and cost reduction. It is essential for AI database integration and the next generation of computing, supporting Intelligent Information Systems and distributed cooperative labor. AI and IT integration are enhancing efficiency, creativity, and digital capabilities, with applications in customer service, healthcare, personalized medicine, and driverless cars. The paper tends to review the developments and trends in information technology using artificial intelligence (AI) as weapons to re-build the future world. With qualitative analysis of previous research studies, the paper tries to explain the role of AI in present information flow as well as for future. And after studying the selective papers it efficiently explains the advantage of AI in both human and environmental way. AI has the potential to significantly impact our lives, but fundamental questions remain unanswered about its extent, scope, and timeline. Current tools are insufficient to predict future AI achievements or fully comprehend its capabilities. To determine the readiness level for different technologies with AI, criteria are defined based on historical evolution. AI has revolutionized the IT industry, improving efficiency, productivity, and quality. However, concerns arise about the potential impact on the workforce, with concerns about job redundancy and potential unjust outcomes in critical areas like employment, finance, and law enforcement.
基金partially funded by Italian Ministry of Health—Ricerca Corrente(no grant number).
文摘Objectives:Treatment of metastatic colorectal cancer(mCRC)includes resection of liver metastases(LM),however,no validated biomarker identifies patients most likely to benefit from this procedure.This meta-analysis aimed to assess the impact of the most relevant molecular alterations in cancer-related genes of CRC(i.e.,RAS,BRAF,SMAD4,PIK3CA)as prognostic markers of survival and disease recurrence in patients with mCRC surgically treated by LM resection.Methods:A systematic literature review was performed to identify studies reporting data regarding survival and/or recurrence in patients that underwent complete liver resection for CRC LM,stratified according to RAS,BRAF,PIK3CA,and SMAD4 mutational status.Hazard ratios(HRs)from multivariate analyses were pooled in the meta-analysis and various adjustment strategies for confounding factors were combined.The search was conducted in numerous databases,including MEDLINE(PubMed),Embase,Cumulative Index to Nursing and Allied Health Literature(CINAHL)(EBSCO host),and WHO Global Index Medicus,through March 18th,2022.Meta-analyses,editorials,letters to the editor,case reports,studies on other primary cancers,studies with primary metastatic sites other than the liver,studies lacking specific oncological outcome variables or genetic data,non-English language studies,and studies omitting residual disease data from liver metastasectomy were excluded.The remaining 47 studies were summarized in a descriptive table which outlines the key characteristics of each study and final results were graphically presented.Results:RAS mutation status was negatively associated with overall survival(OS)(HR,1.68;95%CI,1.54–1.84)and recurrence free survival(RFS)(HR,1.46;95%CI,1.33–1.61).A negative association was also found for BRAF regarding OS(HR,2.64;95%CI,2.15–3.24)and RFS(HR,1.89;95%CI,1.32–2.73)and SMAD4 regarding OS(HR,1.93;95%CI,1.56–2.38)and RFS(HR,1.95;95%CI,1.31–2.91).For PIK3CA only three studies were eligible and no significant association with either OS or RFS could be highlighted.Conclusion:RAS,BRAF,and SMAD4 are negatively associated with OS and RFS in patients undergoing curative liver metastasectomy from colorectal cancer.No conclusion can be drawn for PIK3CA due to the limited literature availability.These data support the integration of RAS,BRAF,and SMAD4 mutational status in the surgical decision-making for colorectal liver metastasis.Nevertheless,we have to consider several limitations,the major ones being the pooling of results from studies that evaluated patient outcomes as either disease-free survival(DFS)or RFS;the inclusion of patients with minimal residual disease and unconsidered potential confounding factors,such as variability in resectability definitions,chemotherapy use,and a potential interaction between biological markers and pre-and post-resection pharmacological treatments.
文摘This study aims to examine the effect of replacing vanadium by niobium and iron on the tribological behavior of hot-isostatic-pressed titanium alloy （Ti-6Al-4V） biomaterial, using a ball-on-disk-type oscillating tribometer, under wet conditions using physiological solution in accordance with the ISO7148 standards. The tests were carried out under a normal load of 6 N, with an AISI 52100 grade steel ball as a counter face. The morphological changes and structural evolution of the nanoparticle powders using different milling times （2, 6, 12 and 18 h） were studied. The morphological characterization indicated that the particle and crystallite size continuously decrease with increasing milling time to reach the lowest value of 4 nm at 18-h milling. The friction coefficient and wear rate were lower in the samples milled at 18 h （0.226, 0.297 and 0.423; and 0.66 × 10-2, 0.87 × 10-2 and 1.51 × 10-2 μm3 N-1 i, tm-1） for Ti-6Al-4Fe, Ti-6A1-7Nb and Ti-6Al-4V, respectively. This improvement in friction and wear resistance is attributed to the grain refinement at 18-h milling. The Ti-6Al-4Fe samples showed good tribological performance for all milling times.
基金supported by the Project of Youth Backbone Teachers of Colleges and Universities in Henan Province(2019GGJS176)the Natural Science Foundation of Henan Province Science and Technology Department(162300410077)+3 种基金the Outstanding Youth Foundation of Science and Technology Innovation of Henan Province(2018JQ0004)the Aeronautical Science Foundation of China(2017ZD55014)the Basic Research Projects of Key Scientific Research Projects Plan in Henan Higher Education Institutions(20zx003)the Internal Research Grant from the Education University of Hong Kong(RG 15/2018-2019R)。
文摘In this article,we are concerned with analytical solutions for a model of inviscid liquid-gas two-phase flow.On the basis of Yuen’s works[25,27–29]on self-similar solutions for compressible Euler equations,we present some special self-similar solutions for a model of inviscid liquid-gas two-phase flow in radial symmetry with and without rotation,and in elliptic symmetry without rotation.Some blowup phenomena and the global existence of the solutions obtained are classified.
文摘Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is governed by the flux properties and effective stress at that plane.At the failure plane,the pore water pressure was higher than the effective stress,and the volume change was the highest.The pore water pressure is a function of the soil profile features(particularly the phreatic zone width)and bedrock motion(horizontal acceleration).The volume change at the failure plane is a function of the intrinsic permeability of the soil and bedrock displacement.The failure plane was predicted to occur during the oscillation with the highest amplitude,disregarding further bedrock motion,which was consistent with low seismic energy densities.Two mechanisms were proposed to explain the persistence of soil liquefaction.The first is the existence of low-permeability layers in the depth range in which the failure planes are predicted to occur.The other allows for the persistence and development of soil liquefaction;it is consistent with homogeneous soils and requires water inflow from bedrock water springs.The latter explains many of the features of soil liquefaction observed during earthquakes,namely,surficial effects,“instant”liquefaction,and the occurrence of short-and long-term changes in the level of the phreatic surfaces.This model(hypothesis),the relationship between the flux characteristics and loss of soil shear strength,provides self-consistent constraints on the depth below the phreatic surfaces where the failure planes are observed(expected to occur).It requires further experimental and observational evidence.Similar reasoning can be used to explain other saturated soil phenomena.
文摘Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and characterized.For some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction method.All the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar ratio.The behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.
基金supported by the Natural Science Foundation of China[grant number 42071453]the geological hazard investigation project of Liaoning Province[grant number 2022020700179]the Fund of National Key Laboratory of Science and Technology on Remote Sensing Information and imagery Analysis,Beijing Research Institute of Uranium Geology[grant number 6142A01210407].
文摘In this paper,the Multi-Temporal Interferometric Synthetic Aperture Radar(MT-InSAR)technology is adopted to monitor the Line of Sight(LOS)displacement of Fushun West Opencast Coal Mine(FWOCM)and its surrounding areas in northeast China using Sentinel-1 Synthetic Aperture Radar(SAR)images acquired from 2018 to 2022.The spatial-temporal evolution of urban subsidence and the south-slope landslide are both analyzed in detail.Comparison with ground measurements and cross-correlation analysis via cross wavelet transform with monthly precipitation data are also conducted,to analyze the influence factors of displacements in FWOCM.The monitoring results show that a subsidence basin appeared in the urban area near the eastern part of the north slope in 2018,with settlement center located at the intersection of E3000 and fault F1.The Qian Tai Shan(QTS)landslide on the south slope,which experienced rapid sliding during 2014 to 2016,presents seasonal deceleration and acceleration with precipitation,with the maximum displacement in vicinity of the Liushan paleochannel.The results of this paper have fully taken in account for the complications of large topographic relief,geological conditions,spatial distribution and temporal evolution characteristics of surface displacements in opencast mining area.The wide range and long time series dynamic monitoring of opencast mine are of great significance to ensure mine safety production and geological disaster prevention in the investigated mining area.
文摘Improving organizational performance can be achieved through business process redesign (BPR). When it comes to modern work practices, organizations must often redesign their processes to keep up. This is where enterprise software comes in, offering a common data infrastructure that enables different parts of the organization to access all necessary financial data. The architecture of network accounting business process is divided into three layers. The core layer lies in the enterprise LAN that it can integrate six business processes information into one unity of financial information and non-financial information, including purchasing, inventory, production, sales, finance and customer service, and it can generate flexibly a variety of accounting statements to meet fully the information users’ demands by providing more complete and more valuable related information. The second layer lies in Intranet among enterprises based on the core layer that it can support the link of business processes and the inter-sharing of information among node enterprises of SCM and other external enterprises. The third layer lies in Internet based on the second layer that it can fit society, enterprise and individual together, the specific lays the solid foundation of business collaboration, remote management, online management and centralized management. The operating mechanisms of the network accounting business processes are as follows. When the business event occurs, the probe can get the event information in real-time and the result is stored in the database. Meanwhile, the drive controller can control the business events in real-time by gaining control criteria and standards from database. In case the standard is exceeded, the event is not allowed to occur. Enterprise’ business staff or external personnel can output automatically the required results through report tools if they had the reading authority. Supported the information system and optimizing processes, the managers can directly use the business event information, criteria and standards to control, guide, regulate and restrict management and operation in real-time, improving operation efficiency and effect. The enterprise can share the accounting information with node enterprises of SCM to bring about JIT that improve the core competitiveness of enterprise. This helps them to function more efficiently, cut costs, enhance customer service, and minimize the risk of human errors. Justifying projects has become increasingly crucial as information systems become more expensive and vital to organizations. IT can pursue two distinct goals: lowering operating costs or improving productivity, based on the difference between operational effectiveness and strategic positioning.
文摘A thermoelectric generation Stirling engine (TEG-Stirling engine) is discussed by employing a low temperature Stirling engine and the dissipative equation of motion derived from the method of thermomechanical dynamics (TMD). The results and mechanism of axial flux electromagnetic induction (AF-EMI) are applied to a low temperature Stirling engine, resulting in a TEG-Stirling engine. The method of TMD produced thermodynamically consistent and time-dependent physical quantities for the first time, such as internal energy ℰ(t), thermodynamic work Wth(t), the total entropy (heat dissipation) Qd(t)and measure or temperature of a nonequilibrium state T˜(t). The TMD analysis produced a lightweight mechanical system of TEG-Stirling engine which derives electric power from waste heat of temperature (40˚CT100˚C) by a thermoelectric conversion method. An optimal low rotational speed about 30θ′(t)/(2π)60(rpm) is found, applicable to devices for sustainable, clean energy technologies. The stability of a thermal state and angular rotations of TEG-Stirling engine are specifically shown by employing properties of nonequilibrium temperature T˜(t), which is also applied to study optimal fuel-injection and combustion timings of heat engines.
文摘Background: Mobility in older adults can be impaired after acute illness or hospitalization, and the level of severity can be used as a predictor of one’s ability to return to independent living. Patients are often referred to skilled nursing facilities in hopes of improving their mobility. We wanted to prove that rehabilitative services at Skilled Nursing Facilities improve overall outcomes. Methods: We conducted a retrospective analysis of data from 4612 patients admitted for short-term rehabilitation in a large nursing home chain in California. Our aim was to determine whether patients’ mobility scores, as measured by rehabilitative staff, significantly improved by time of discharge compared to their scores at admission. Mobility scores were rated from 1 to 6, with 1 being the most dependent on aid and 6 being the most independent, over a variety of tasks at admission and compared to scores at discharge. Pearson’s correlations were performed to determine if there were significant relationships in the data: the Pearson’s correlation coefficient was used to describe the relationships between patient admission to a skilled nursing facility and medical improvement upon discharge. Results: The study demonstrated a statistically significant improvement in patients’ mobility scores upon discharge, with Medicare insured patients showing on average 57% improvement and Managed Care insured patients showing on average 59% improvement. Additionally, admission scores appeared to be predictive of the patient’s outcome at discharge. Conclusions: The values and consistency of improvement support the use of acute rehabilitative services in skilled nursing facilities. An equation can be formulated that evaluates patients’ estimated mobility statuses upon discharge from facilities based on their conditions on their arrivals. With this, new interventions can be studied and compared to the current standard of care by using these measurements. They can determine if further improvements can be made to increase patient outcomes.
