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Role of urea in the retention of DON in soil by clay minerals:Analysis based upon molecular weight 被引量:1
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作者 Leyun Wang Miao Li Xiang Liu 《Journal of Environmental Sciences》 2025年第4期362-372,共11页
As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important facto... As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important factor in retaining DON.However,the effect of urea on the retention of DON with different molecular weights by clay minerals is unknown.In this study,the retention of both low-molecular weight DON(LMWD)and high-molecular weight DON(HMWD)by clay minerals in the presence of urea was investigated.For this purpose,batch adsorption and soil column leaching experiments,characterization analysis(Fourier transform infrared spectroscopy X-ray diffraction,and X-ray photoelectron spectroscopy),and molecular dynamics simulations were carried out.Urea had a positive effect on the adsorption of LMWD,whereas a competitive effect existed for the adsorption of HMWD.The dominant interactions among DON,urea,and clay minerals included H-bonding,ligand exchange,and cation exchange.The urea was preferentially adsorbed on clay minerals and formed a complex,which provided more adsorption sites to LMWD and only a few to HMWD.The presence of urea increased the retention of LMWD and decreased the retention of HMWD in clay minerals.The retention capacity of LMWD increased by 6.9%–12.8%,while that of HMWD decreased by 6.7%–53.1%.These findings suggest that LMWD tended to be trapped in soils,while HMWD was prone to be leached into groundwater,which can be used to evaluate the leaching of DON from soil to groundwater. 展开更多
关键词 UREA Dissolved organic nitrogen Clay mineral Molecular dynamics RETENTION
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Multi-scenario simulation of land use change and its impact on ecosystem services in the northeastern edge of the Qinghai-Xizang Plateau,China 被引量:1
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作者 ZHANG Xuebin LIU Yanni +3 位作者 YIN Junfeng SHI Peiji FENG Haoyuan SHI Jing 《Journal of Arid Land》 2025年第2期145-166,共22页
The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity conservation.Gannan Tibetan Autonomous Prefecture(hereinafter ref... The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity conservation.Gannan Tibetan Autonomous Prefecture(hereinafter referred as Gannan Prefecture),located on the northeastern edge of the QXP,represents a fragile alpine ecosystem in which land use change significantly impacts ecosystem services(ESs).This study established a comprehensive framework,utilizing the Patch-generating Land-Use Simulation(PLUS)model coupled with the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to predict land use patterns under the natural development scenario,cultivated land protection scenario,and ecological protection scenario for Gannan Prefecture by 2030 and evaluated four critical ESs:habitat quality(HQ),water yield(WY),soil retention(SR),and carbon storage(CS).The primary aim is to elucidate the impacts of dynamic land use change on ESs.The results revealed that,from 2000 to 2020,HQ exhibited minimal variation,whereas CS experienced a slight decline.Conversely,WY and SR showed significant improvements.Under the natural development scenario,construction land was projected to increase by 4247.74 hm^(2),primarily at the expense of forest land.The cultivated land protection scenario anticipated an increase in farmland by 2634.36 hm^(2),which was crucial for maintaining food security.The ecological protection scenario predicted a notable expansion of forest land,accompanied by a restrained development rate of construction land.The ecological protection scenario also showed an increase in the ecosystem service index(ESI),encompassing 26.07%of the region.Forest land and grassland emerged as the primary contributors to ESs,while construction land substantially impacted WY.Water bodies exhibited minimal contribution to ESs.This study enhanced the understanding of land use change impacts on ESs in fragile and high-altitude ecosystems,offering essential theoretical frameworks and practical direction for forthcoming ecological policy and regional planning endeavors. 展开更多
关键词 PLUS-InVEST model ecosystem service habitat quality water yield soil retention carbon storage Qinghai-Xizang Plateau
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Dynamic deformation characteristics and microscopic analysis of xanthan gum-treated silty soil during wetting process 被引量:1
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作者 Junran Zhang Mengyi Jia +4 位作者 Tong Jiang Shoji Kato De'an Sun You Gao Zheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1149-1162,共14页
The deformation characteristics of silty soils under vibrational loads can easily change due to the wetting process,leading to the failure of roadbed structures.Commonly used methods for improving silty soils in engin... The deformation characteristics of silty soils under vibrational loads can easily change due to the wetting process,leading to the failure of roadbed structures.Commonly used methods for improving silty soils in engineering often yield unsatisfactory economic and ecological outcomes.As an environment-friendly soil improvement material,Xanthan gum has broad application prospects and is therefore considered a solidifying agent for enhancing silty soil properties in the Yellow River Basin.In this study,a series of tests is conducted using a scanning electron microscope and a dynamic triaxial testing apparatus to investigate the microstructure and dynamic deformation characteristics of unsaturated silty soil with varying xanthan gum contents during the wetting process.The results show that xanthan gum effectively fills voids between soil particles and adheres to their surfaces,forming fibrous and network structures.This modification enhances the inherent properties of the silty soil and significantly improves its stability under dynamic loading.Specifically,with increasing xanthan gum content,the dynamic shear modulus increases while the damping ratio decreases.During the wetting process,as suction decreases,the dynamic shear modulus decreases while the damping ratio increases.Xanthan gum reduces the sensitivity of the dynamic deformation characteristics of the treated silty soil to changes in suction levels.Finally,based on the modified Hardin-Drnevich hyperbolic model,a predictive model for the dynamic shear modulus and damping ratio of treated silty soil is proposed,considering the xanthan gum content.These research findings provide a theoretical basis for the construction and maintenance of water conservancy,slope stabilization,and roadbed projects in the Yellow River Basin. 展开更多
关键词 Xanthan gum Unsaturated silty soil dynamic deformation characteristics Scanning electron microscope Water retention characteristics
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Cauda equina syndrome with urinary retention as a postoperative complication of lumbar spine surgery:A case report
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作者 Kai-Wu Yang Wei-Hong Lai Da-Wei Huang 《World Journal of Clinical Cases》 SCIE 2025年第10期40-45,共6页
BACKGROUND Cauda equina syndrome(CES)is characterized by a group of symptoms that may be caused by inflammation,spinal cord compression,venous congestion,or ischemia.This syndrome is commonly an indication for surgica... BACKGROUND Cauda equina syndrome(CES)is characterized by a group of symptoms that may be caused by inflammation,spinal cord compression,venous congestion,or ischemia.This syndrome is commonly an indication for surgical intervention but has not been determined as a postoperative complication following surgery for lumbar spine disease.CASE SUMMARY To report the case of a 54-year-old male patient who had CES following spinal surgery,with no obvious compression lesions found during re-exploration,suggesting that vascular insufficiency may have contributed to the condition.Furthermore,a series of urodynamic studies on bladder recovery patterns in such complications have also been investigated.CONCLUSION Postoperative CES requires urgent imaging and exploration to rule out compression;noncompressive cases,including vascular insufficiency may performed conservative management. 展开更多
关键词 Cauda equina syndrome Lumbar spine surgery Urinary retention Urodynamic study Postoperative complication Case report
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Retention of international nurses in receiving country:Voices of Indonesian nurses in Japanese healthcare facilities
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作者 Ferry Efendi Eka Mishbahatul Mar’ah Has +3 位作者 Rifky Octavia Pradipta Grace Solely Houghty Hisaya Oda Yuko Tsujita 《International Journal of Nursing Sciences》 2025年第1期3-11,共9页
Objectives:This study aimed to explore the voices of Indonesian migrant nurses on their retention in Japanese healthcare facilities.Methods:A descriptive qualitative study was conducted between June and September 2023... Objectives:This study aimed to explore the voices of Indonesian migrant nurses on their retention in Japanese healthcare facilities.Methods:A descriptive qualitative study was conducted between June and September 2023.The snowball sampling method was utilized to recruit 22 Indonesian nurses working in healthcare facilities in seven prefectures of Japan.Semi-structured interviews were conducted based on their shared experiences.All interview data were audio-recorded,transcribed verbatim,and analyzed using thematic analysis.Results:Six prominent themes and 15 subthemes emerged:1)organizational factors(caring leader,involvement in decision making,career development,and participation in training);2)social support systems(group support,colleagues support and friend support);3)individual drive(lifelong learning and persistent);4)national policies(government support in public service and flexibility in finding a comfortable placement);5)family factors(positive support of child education and development and maintaining relationship with spouse);and 6)economic factors(staying due to high salary and increasing income streams).Conclusions:Retention of Indonesian migrant nurses in Japan is a multifaceted challenge that hinges on various interconnected factors.This study has gone some way toward enhancing our understanding of international nurse retention in the receiving countries.Corresponding supports at the individual,family,organizational,economic,social,and national policy levels should be considered to keep them in their destination countries. 展开更多
关键词 Indonesia MIGRATION Nurses RETENTION Qualitative study
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Inclusion of sorghum grain rich in condensed tannins in the diet of steers did not affect the nitrogen utilization efficiency but increased the urine nitrous oxide emissions
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作者 Biao Xie Changfa Mao +3 位作者 Xu Shen Yufeng Liu Qingyue Liang Guangyong Zhao 《Journal of Integrative Agriculture》 2025年第4期1296-1309,共14页
The objectives of this study which included two experiments were to investigate the effects of dietary inclusion of sorghum grain rich in condensed tannins(CT)(18.9 g kg^(–1)dry matter(DM))on nitrogen(N)metabolism an... The objectives of this study which included two experiments were to investigate the effects of dietary inclusion of sorghum grain rich in condensed tannins(CT)(18.9 g kg^(–1)dry matter(DM))on nitrogen(N)metabolism and urine nitrous oxide(N_(2)O)emissions of beef steers.In experiment 1,six Limousin×Luxi crossbreed steers with an initial liveweight of(245.0±18.7)kg were used as experimental animals.Three levels of sorghum grain,i.e.,0,167 and 338 g kg^(–1)DM were included in diets as experimental treatments.The animals and the treatments were randomly assigned to a replicated 3×3 Latin square design.In experiment 2,static incubation technique was used to determine the N_(2)O emissions of the urine samples collected in experiment 1.The results of experiment 1 showed that dietary inclusion of sorghum grain linearly increased the faecal N excretion(P=0.001),the total N excretion(P=0.010)and the faecal N to N intake ratio(P=0.021),but it did not affect the N retention and the N utilization efficiency(P>0.10).The plasma metabolomic data showed that dietary inclusion of sorghum grain increased the relative concentrations of phenolic acid(N1,N5,N10-tris-trans-p-coumaroylspermine and prenyl cis-caffeate)and carnitine(3-hydroxyisovalerylcarnitine and linoelaidyl carnitine).The results also showed that dietary inclusion of sorghum grain linearly increased the urinary urea excretion(P=0.010)and decreased the urinary excretion of purine derivatives(P=0.041)as well as the estimated rumen microbial N supply(P=0.012)based on urinary purine derivatives.The results of experiment 2 showed that including sorghum grain in the diet linearly increased the average concentrations of NH_(4)^(+)-N(P=0.012),NO_(2)^(–)-N(P=0.009),NO_(3)^(-)-N(P=0.001)and the total inorganic N(P<0.001)in the soil enriched with urine samples.The urine sample N_(2)O-N flux(P=0.001),the estimated steer urine N_(2)O-N flux(P=0.021)and the N_(2)O-N to urinary N ratio(P=0.038)linearly increased with increasing inclusion of sorghum grain in the diet.In conclusion,dietary inclusion of sorghum grain containing high CT at 167 and 338 g kg^(–1)DM did not affect the N utilization efficiency of steers but increased the urine N_(2)O-N emissions by 5.7 and 31.4%,respectively.For reducing the N_(2)O emissions to the environment,high levels of sorghum grain should not be included in the diet of steers. 展开更多
关键词 CATTLE nitrogen retention nitrous oxide SORGHUM URINE
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Concentration and retention of ascorbic acid,carotenoids,and sugars in fresh-cut lettuce in modified atmosphere packaging
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作者 Jinita Sthapit Kandel Ivan Simko +1 位作者 Ryan J.Hayes Beiquan Mou 《Horticultural Plant Journal》 2025年第1期303-313,共11页
Fresh-cut lettuce is widely used in ready-to-eat salads sold in modified atmosphere packages (MAP).Even in MAP,fresh-cut lettuce has short shelf life that results in loss of nutrients.Lettuce cultivars exhibit genetic... Fresh-cut lettuce is widely used in ready-to-eat salads sold in modified atmosphere packages (MAP).Even in MAP,fresh-cut lettuce has short shelf life that results in loss of nutrients.Lettuce cultivars exhibit genetic variation for shelf life in MAP,but their variation for nutrient retention is not known.Fifty accessions were evaluated for initial content of ascorbic acid (AsA),carotenoids,and sugars and their retention in storage.Accessions with high content and/or good retention of one or more nutrients were identified.The romaine accession ‘Floricos’ had high levels of all the three nutrients.Accessions with relatively high retention of all the three nutrients were ‘Salinas 88’,‘Siskiyou’,‘Solar’,SM09A,‘Romance’,and ‘Green Towers’.Romaine cultivars,‘Balady Barrage’,‘Green Towers’,and ‘Darkland’ had relatively high initial levels of all tested nutrients and good rate of their retention.There was no clear correlation between initial AsA/carotene concentrations and their retention rates,suggesting that besides content,retention of nutrients should also be a breeding target in a lettuce nutritional improvement program.Statistical analyses with the Pearson's correlation coefficient determined a negative relationship between tissue deterioration(AUDePS) and retention of all tested nutrients[r of-0.52 (P<0.0001) for AsA,-0.27 (P<0.01) for total carotene,and-0.59 (P<0.0001) for total sugars],suggesting that an increase in tissue deterioration intensifies nutrient decay.Broad-sense heritability (H^(2)) across the experiments was0.15 for AsA,0.23 for total carotene,and 0.50 for total sugars.Identification of germplasm with high nutrient content,extended shelf life and good nutrient retention provides valuable information for the lettuce industry and associated breeding programs. 展开更多
关键词 LETTUCE Shelf life Nutrient retention Ascorbic acid CAROTENE Sugars
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Mitigating clay swelling and permeability loss in thermal EOR with a quaternary ammonium clay stabilizer under high-temperature low-salinity conditions
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作者 Aisha Labak Peyman Pourafshary 《Energy Geoscience》 2025年第4期41-51,共11页
Clay swelling and fines migration pose significant challenges to thermally enhanced oil recovery(EOR)operations,particularly in clay-rich formations.This study systematically investigates clay swelling behavior and pe... Clay swelling and fines migration pose significant challenges to thermally enhanced oil recovery(EOR)operations,particularly in clay-rich formations.This study systematically investigates clay swelling behavior and permeability impairment under high-temperature,low-salinity(HTLS) conditions and evaluates various inhibition methods to mitigate formation damage.To ensure realistic analysis,data and materials from a field with similar issues in Kazakhstan were used.Static/dynamic swelling tests demonstrated that a quaternary ammonium-based inhibitor consistently provided superior clay stabilization through effective ion exchange and surface charge modification mechanisms.In distilled water at 100℃,inhibitor-treated samples maintained 48.89 % of their original permeability,while untreated samples exhibited severe damage,retaining only 17.05 %.Additionally,this chemical inhibitor significantly lowered the critical salt concentration(CSC),effectively stabilizing clay at 4920 ppm salinity compared to 7380 ppm required without treatment.Scanning electron microscopy(SEM) imaging corroborated these results,revealing that inhibitor-treated clay maintains a compact and coherent structure,in stark contrast to the pronounced swelling,delamination,and structural deterioration observed in untreated clay samples.Nevertheless,this quaternary ammonium-based clay stabilizer presents a robust and promising solution for reducing clay swelling-induced damage,sustaining reservoir permeability,and improving thermal EOR performance in swelling-prone formations. 展开更多
关键词 Clay swelling INHIBITOR Temperature Thermal damage Permeability retention
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Grain matrix modification via superheated steam:Impacts on nutrients,flavor and storage driven processing adaptability
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作者 Jian Ye Fang Wang Ruge Cao 《Grain & Oil Science and Technology》 2025年第4期307-317,共11页
Whole grain foods are valued for their health benefits but face persistent challenges related to sensory acceptability,storage stability,and processing complexity.This review evaluates superheated steam(SHS)technology... Whole grain foods are valued for their health benefits but face persistent challenges related to sensory acceptability,storage stability,and processing complexity.This review evaluates superheated steam(SHS)technology as a disruptive approach to whole grain processing,highlighting its ability to enhance nutritional retention,modulate microstructure,and extend shelf-life under low-oxygen,high-temperature conditions.SHS suppresses oxidative degradation,restructures starch–protein–lipid matrices,and inactivates enzymes and spoilage microorganisms with minimal nutrient loss.Despite these advantages,SHS faces limitations,including uneven heat penetration in dense kernels,component specific thermal sensitivity and higher equipment costs.By integrating mechanistic insights with practical outcomes,this paper synthesizes recent advances,highlights key scientific and technological gaps,and proposes strategies for industrial application and integration with intelligent food processing systems.This review provides a concise theoretical and technical roadmap for sustainable whole grain innovation. 展开更多
关键词 Grain processing Superheated steam Nutrient retention Sensory properties Shelf life
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Long-term defense endeavors against erosion on a muddy deltaic coast:Lessons and implications
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作者 Yu-Hai Wang An-Jun Deng +1 位作者 Yan-Hong Wang Yi-Qin Xie 《River》 2025年第4期525-534,共10页
Shoreline erosion has been a pernicious problem facing many countries around the world.It causes the degradation and vulnerability of coastal eco-environments,and imposes considerable pressures upon coastal economic,s... Shoreline erosion has been a pernicious problem facing many countries around the world.It causes the degradation and vulnerability of coastal eco-environments,and imposes considerable pressures upon coastal economic,social developments in the context of climate change and sea-level rising.The muddy coast of the abandoned Yellow River delta at Binhai,Jiangsu Province,China has experienced chronic erosion since 1855 when the Yellow River avulsed to north China.A variety of hard structures,that is,seawall,groin,jetty,breakwater,and so forth were emplaced and reinforced to withstand the shoreline retreat and concomitant beach loss.These engineering solutions have been proved unsuccessful or ineffective in their objectives.An overview is presented on the multi-decadal defense endeavors with technical lessons and management implications learnt.A SHIAA(site-specific,holistic,integrative,adaptive,affordable)tenet is put forward to achieve the sustainability in a coastal erosion mitigation scheme.The merit and limitation of nature-based solutions(NBS)applied in coastal protection is further discussed. 展开更多
关键词 beach retention deltaic coast erosion mitigation nature-based solution sustainability
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Retaining nurses in Sub-Saharan Africa:A systematic review and meta-analysis
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作者 Evans Kasmai Kiptulon Mohammed Elmadani +3 位作者 Mokaya Peter Onchuru Anna Szőllősi Miklós Zrínyi Adrienn Ujváriné Siket 《International Journal of Nursing Sciences》 2025年第3期301-309,I0007,共10页
Objectives This study aimed to determine the current prevalence of nurse retention in Sub-Saharan Africa(SSA),evaluate the strategies and interventions in SSA countries used to retain their nurses,and identify the key... Objectives This study aimed to determine the current prevalence of nurse retention in Sub-Saharan Africa(SSA),evaluate the strategies and interventions in SSA countries used to retain their nurses,and identify the key challenges impeding nurse retention.Methods A systematic review and meta-analysis were conducted.An electronic search was performed in August 2024 across multiple databases,including PubMed,Ovid Medline,Embase,CINAHL,Scopus,and grey literature sources.The studies were screened using Covidence,and quality assessments were conducted using the Mixed Methods Appraisal Tool.Results A total of 31 articles were included in the review.Meta-analysis revealed that the pooled nurses’retention rate in SSA was 53%(95%CI:38%–67%;I2=97%),while the pooled intention to stay(ITS)rate at work was 57%(95%CI:43%–71%;I2=99%).Subgroup analysis by region showed that the ITS rate was highest in East Africa(65%),followed by West Africa(63%),and lowest in Southern Africa(35%).Effective retention strategies included financial and non-financial incentives,increased production and training of nurses,steering students to shortage specialties,adequate rural housing,facility level improvements,availability of career and professional progression opportunities,nurses’recognition and involvement,employment terms,transparency and predictable management of human resources,supportive work environments,leadership,religious factors,and stakeholders’collaborations.Key challenges to nurses’retention include inadequate healthcare funding,governance issues,poor remuneration and working conditions,political interference,high unemployment rates,ineffective mobility management,unregulated international migration,and active recruitment by wealthier nations.Conclusions Nurse retention in SSA remains critically low.Interventions should be formulated for the above-mentioned effective improvement strategies to address these systemic challenges in order to retain nurses in SSA. 展开更多
关键词 Intention to stay META-ANALYSIS NURSE RETENTION Sub-Saharan Africa Systematic review
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Comparative evaluation of retentive capacity of three different attachment systems for implant retained overdentures:An in vitro study
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作者 Radha Chauhan Narendra Padiyar +2 位作者 Pragati Kaurani Ajay Gupta Sachin Chauhan 《World Journal of Methodology》 2025年第3期114-123,共10页
BACKGROUND The primary issue in managing edentulous patients is the severely resorbed mandibular ridge,particularly in older individuals with diminished adaptive capacities.This compromised situation leads to the fabr... BACKGROUND The primary issue in managing edentulous patients is the severely resorbed mandibular ridge,particularly in older individuals with diminished adaptive capacities.This compromised situation leads to the fabrication of inadequate dentures that lack retention and stability,potentially causing psychosocial issues.AIM To determine the difference in retentive capacity between three attachment systems in implant-retained overdentures.METHODS Three edentulous mandibular models were fabricated using heat-cured polymethacrylate resin,with two implant replicas placed in the intra-foraminal region of each model.30 acrylic resin mandibular overdentures were fabricated with provisions for three different overdenture attachment systems:A prefabricated ball/O-ring attachment,a locator attachment system,and an equator attachment system.Each model was subjected to 15000 pulls using a universal testing machine to remove the overdenture from the acrylic model and the force data were recorded.RESULTS The ball/O-ring attachment system demonstrated superior retentive capacity for 15 years,while the locator and equator attachment systems maintained excellent retentive capacity for 5 years.CONCLUSION The ball/O-ring attachment system outperformed better than the other two attachment systems regarding retentive capacity.The locator and equator attachment systems presented sufficient retentive abilities until 15000 cycles.After 7500 cycles,significant differences in retentive force between the systems evolved. 展开更多
关键词 DENTURES Overdenture attachment systems EQUATOR Dislodging cycles Retentive capacity
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Impact of CO_(2)as an oxidant on the decarburization and chromium retention and an approach for CO_(2)recycling
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作者 Yun Zhou Wenzhi Xia +1 位作者 Guangsheng Wei Haichuan Wang 《Chinese Journal of Chemical Engineering》 2025年第1期203-206,共4页
This study explores the unique role of CO_(2)as an oxidant in stainless steel smelting,focusing on its effectiveness in decarbonization and chromium retention.The research begins by theoretically demonstrating that al... This study explores the unique role of CO_(2)as an oxidant in stainless steel smelting,focusing on its effectiveness in decarbonization and chromium retention.The research begins by theoretically demonstrating that although the introduction of CO_(2)increases the CO partial pressure in the reaction system,the decarburization and chromium(Cr)retention capabilities of CO_(2)can still be stably maintained through the rational adjustment of the molten steel composition,temperature,and inert gas proportions.Further experimental findings indicate that chromium does not exhibit significant oxidation losses when the carbon(C)content exceeds 1.0%(mass).Finally,a novel CO_(2)recovery and utilization approach is proposed,integrating CO_(2)capture from smelting flue gas and recycling it for smelting,reducing O_(2)consumption and energy costs.This innovative process,compatible with existing smelting plants,presents a promising pathway towards carbon neutrality in the iron and steel industry,bridging theoretical insights with practical applications. 展开更多
关键词 Carbon dioxide Oxidation DECARBURIZATION Chromium retention Chemical reaction Stainless steel smelting
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Effects of hyperalkaline solutions on the water retention properties and microstructure of the opalinus clay from the lower sandy facies of mont terri site,Switzerland
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作者 Yara Barakat Nadia Mokni +2 位作者 Yu-Jun Cui Pierre Delage Frédéric Bernier 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1723-1737,共15页
In Switzerland,the Opalinus Clay has been selected as a potential host rock for the deep geological disposal of radioactive waste due to its low hydraulic conductivity and favorable swelling properties.During the oper... In Switzerland,the Opalinus Clay has been selected as a potential host rock for the deep geological disposal of radioactive waste due to its low hydraulic conductivity and favorable swelling properties.During the operational phase of the repository,the host rock will be exposed to pH values as high as 13.5 due to concrete degradation,which will certainly affect its hydraulic properties.This study investigates the effect of pH increase on the water retention properties of Opalinus Clay.A series of samples from the lower sandy facies of the Mont Terri site in Switzerland,at initial dry state,were exposed to a hyperalkaline solution of pH=13.5 and to the synthetic water of pH=7.5 at different water contents.After equilibrium,the total suction was measured with a dew point potentiometer and microstructural analyses were conducted via mercury intrusion porosimetry(MIP)and nitrogen adsorption-desorption technique.It was found that the total suction decreased with hydration and pH increase.Since the two investigated solutions have the same osmotic suction,the decrease in total suction was attributed to the decrease in matric suction.Indeed,the total porosity increased with saturation and pH increase.This was confirmed by MIP data that evidenced an increase in the proportion of macropores,and by Barret eJoynereHalenda(BJH)data that showed mesopore generation.The specific surface area(SSA)also increased.The previous results were due to mineral hydration and,exclusively in the case of alkaline solution,to(1)the dissolution of quartz and calcite and(2)the acid-base reactions,which were concentrated at the edges of the clay particles,leading to an increase in negatively charged groups and thus to a face-to-face association of the clay particles(dispersion),causing an increase in the repulsive forces between the clay particles.In addition,the weakening of covalent bonds led to the primary dissolution of clay minerals,i.e.silicon and aluminum detachment. 展开更多
关键词 Opalinus clay Lower sandy facies Water retention properties Porosity MICROSTRUCTURE DISSOLUTION
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Image Steganalysis Based on an Adaptive Attention Mechanism and Lightweight DenseNet
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作者 Zhenxiang He Rulin Wu Xinyuan Wang 《Computers, Materials & Continua》 2025年第10期1631-1651,共21页
With the continuous advancement of steganographic techniques,the task of image steganalysis has become increasingly challenging,posing significant obstacles to the fields of information security and digital forensics.... With the continuous advancement of steganographic techniques,the task of image steganalysis has become increasingly challenging,posing significant obstacles to the fields of information security and digital forensics.Although existing deep learning methods have achieved certain progress in steganography detection,they still encounter several difficulties in real-world applications.Specifically,current methods often struggle to accurately focus on steganography sensitive regions,leading to limited detection accuracy.Moreover,feature information is frequently lost during transmission,which further reduces the model’s generalization ability.These issues not only compromise the reliability of steganography detection but also hinder its applicability in complex scenarios.To address these challenges,this paper proposes a novel deep image steganalysis network designed to enhance detection accuracy and improve the retention of steganographic information through multilevel feature optimization and global perceptual modeling.The network consists of three core modules:the preprocessing module,the feature extraction module,and the classification module.In the preprocessing stage,a Spatial Rich Model(SRM)filter is introduced to extract the high-frequency residual information of the image to initially enhance the steganographic features;at the same time,a lightweight Densely Connected Convolutional Networks(DenseNet)structure is proposed to enhance the effective transmission and retention of the features and alleviate the information loss problem in the deep network.In the feature extraction stage,a hybrid modeling structure combining depth-separated convolution and ordinary convolution is constructed to improve the feature extraction efficiency and feature description capability;in addition,a dual-domain adaptive attention mechanism integrating channel and spatial dimensions is designed to dynamically allocate feature weights to achieve precise focusing on the steganography-sensitive region.Finally,the classification module adopts dual fully connected layers to realize the effective differentiation between coverage and steganography maps.These innovative designs not only effectively improve the accuracy and generalization ability of steganography detection,but also provide a new efficient network structure for the field of steganalysis.Numerous experimental results show that the detection performance of the proposed method outperforms the existing mainstream methods,such as SR-Net,TSNet,and CVTStego-Net,on the publicly available dataset BOSSbase and BOSW2.Meanwhile,multiple ablation experiments further validate the validity and reasonableness of the proposed network structure.These results not only promote the development of steganalysis technology but also provide more reliable detection tools for the fields of information security and digital forensics. 展开更多
关键词 Image steganalysis lightweight densenet adaptive attention feature focusing information retention
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Development of switchable deep eutectic solvents:Applications in extraction of natural products
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作者 Yuan Yan Lingqi Shen +3 位作者 Yu Wang Bincheng Gong Zuguang Li Hongdeng Qiu 《Chinese Chemical Letters》 2025年第11期36-48,共13页
Green extraction of bioactive components from natural sources has been a hot topic in the field of chemistry and biology.As a kind of green solvents,deep eutectic solvents(DESs)have unique advantages in the extraction... Green extraction of bioactive components from natural sources has been a hot topic in the field of chemistry and biology.As a kind of green solvents,deep eutectic solvents(DESs)have unique advantages in the extraction of bioactive substances.In recent years,as a new subgroup of DESs,the switchable deep eutectic solvents(SDESs)can realize reversible phase switching between hydrophobic and hydrophilic by external driving forces(CO_(2)/p H/temperature),allowing for the extraction of different polar components while avoiding the problem of difficult recovery of DESs.The application of SDESs reduces the consumption of large amounts of organic solvents during the extraction process,thereby promoting sustainability.In the meanwhile,it presents an advantage over traditional extraction methods in preserving product activity.Based on the recent researches on SDESs,this work summarized the composition,driving factors,and conversion mechanism of SDESs.The applications of SDESs in the extraction of natural products were primarily highlighted to provide a reference for future research. 展开更多
关键词 Switchable deep eutectic solvents Natural products Activity retention EXTRACTION REVIEW
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Simultaneous assessment of effects of variations in temperature and hydraulic retention time on membrane fouling in membrane bioreactors
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作者 Horieh Akbari Hossein Hazrati +1 位作者 Abbas Nazmkhah Hanieh Shokrkar 《Water Science and Engineering》 2025年第2期200-208,共9页
Membrane fouling remains the primary economic barrier to the widespread implementation of membrane bioreactors (MBRs), despite the fact that they lead to the production of high-quality effluent. Operational conditions... Membrane fouling remains the primary economic barrier to the widespread implementation of membrane bioreactors (MBRs), despite the fact that they lead to the production of high-quality effluent. Operational conditions are critical factors influencing membrane fouling. This study aimed to investigate the simultaneous impacts of temperature and hydraulic retention time (HRT) variations on membrane fouling. Experiments were conducted at three different temperatures (18°C, 25°C, and 32°C) and HRTs (6 h, 9 h, and 15 h). The results demonstrated that increases in both temperature and HRT contributed to a reduction in membrane fouling. Additionally, a positive interaction between temperature and HRT was observed in the linear slope variation of membrane permeation, with temperature variations exerting a greater influence on membrane fouling than HRT variations. Fouling factor analysis revealed that increases in temperature and HRT led to decreased concentrations of soluble microbial products (SMP) and extracellular polymeric substances (EPS), particularly carbohydrates, in the activated sludge. Analyses of the cake layer of the membrane indicated that increasing temperature and HRT reduced EPS levels, particularly polysaccharides and proteins;altered primary protein structure;and increased the mean particle size distribution. Ultimately, these changes led to reductions in both reversible and irreversible hydraulic resistances. This study highlights the importance of optimizing operational parameters such as temperature and HRT to enhance membrane performance and treatment efficiency in MBR systems while mitigating fouling. 展开更多
关键词 Membrane bioreactor Membrane fouling Operation conditions Hydraulic retention time TEMPERATURE
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Increased incidence of gastric food retention during endoscopic retrograde cholangiopancreatography in liver transplant recipients:A retrospective cohort study
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作者 Sitong Chen Vicki McGarrigle +4 位作者 Rhys Vaughan Yuto Shimamura Sujievvan Chandran Leonardo Zorron Cheng Tao Pu Marios Efthymiou 《World Journal of Transplantation》 2025年第4期227-232,共6页
BACKGROUNDGastric food retention during endoscopic retrograde cholangiopancreatography(ERCP) can lead to complications such as aspiration and failed procedure. Livertransplant (LT) recipients are exposed to an increas... BACKGROUNDGastric food retention during endoscopic retrograde cholangiopancreatography(ERCP) can lead to complications such as aspiration and failed procedure. Livertransplant (LT) recipients are exposed to an increased risk of impaired gastrointestinalmotility due to surgical alterations, immunosuppressive therapy, andpost-transplant complications. Given the high frequency of ERCP in this population,our anecdotal experience suggests an increased incidence of gastric foodretention at the time of the procedure.AIMTo evaluate the association between LT and gastric food retention observed atERCP over a two-year period.METHODSThis retrospective study included all patients who underwent standard ERCP atour institution between 2022 and 2024. Data were collected on demographics,medical history including LT and procedural details.RESULTSA total of 1100 patients underwent ERCP, including 238 LT recipients (22%).Gastric food retention was observed 17 patients (1.5%). The incidence was significantly higher in LT recipientscompared to non-transplant patients (3.8% vs 0.9%, P = 0.004). Multivariate analysis confirmed that LT recipientswere independently associated with an increased risk of food retention.CONCLUSIONLT recipients demonstrated over three-fold increased incidence of gastric food retention during ERCP. This shouldbe considered in pre-procedural assessment and preparation in this patient population. 展开更多
关键词 Liver transplantation Endoscopic retrograde cholangiopancreatography GASTROPARESIS Gastric stasis Gastric food retention ENDOSCOPY
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Erosion on marginal slopes of unpaved roads in semi-arid Brazil,and the role of Caatinga vegetation in sediment retention and disconnectivity
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作者 Teresa Raquel Lima FARIAS Maria Thereza Rocha CHAVES +3 位作者 Cicero Lima de ALMEIDA Pedro Henrique Augusto MEDEIROS José Carlos de ARAÚJO Joaquín NAVARRO-HEVIA 《Journal of Arid Land》 2025年第4期500-514,共15页
Vegetation plays a major role in soil protection against erosion effects,and studies have also highlighted its importance in retaining sediments from roadside slopes.Yet,hydro-sedimentological studies under natural pr... Vegetation plays a major role in soil protection against erosion effects,and studies have also highlighted its importance in retaining sediments from roadside slopes.Yet,hydro-sedimentological studies under natural precipitation conditions are still scarce in semi-arid areas due to difficulties in monitoring the few and very concentrated precipitation events.Quantifying sediment connectivity and yield at watershed scale,often highly impacted by the erosion of unpaved roads,is necessary for management plans.This study aims to evaluate the efficiency of native vegetation on roadside slope segments in Caatinga biome in retaining sediments and conserving the soil in a semi-arid area of Brazil.Surface runoff,sediment concentration,and yield measurements were measured from 34 natural precipitation events in four years on two slopes with and without vegetation.The runoff coefficients of the plot with no vegetation varied from 3.0%to 58.0%,while in the vegetated plot,they showed variation from 1.0%to 21.0%.The annual specific sediment yield ranged from 4.6 to 138.7 kg/(hm^(2)•a)for the vegetated plot and from 34.9 to 608.5 kg/(hm^(2)•a)for the unvegetated one.These results indicate a 4 to 12 times higher soil loss on the unvegetated slope in relation to the vegetated one and demonstrate that natural Caatinga vegetation acts as an effective barrier against surface-transported sediments.Moreover,natural Caatinga vegetation present on the slope plays an important role in breaking connectivity between sediment flows from unpaved roads and the watershed drainage system.These findings indicate that investments in unpaved road and roadside slope restoration,not only enhance road infrastructure but also promote environmental gains by reducing the impact of erosion. 展开更多
关键词 erosion control road erosion road slopes road impact sediment retention slope restoration
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Pivotal roles of biglycan and decorin in regulating bone mass,water retention,and bone toughness
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作者 Rui Hua Yan Han +6 位作者 Qingwen Ni Roberto J.Fajardo Renato V.Iozzo Rafay Ahmed Jeffry S.Nyman Xiaodu Wang Jean X.Jiang 《Bone Research》 2025年第1期48-61,共14页
Proteoglycans,key components of non-collagenous proteins in the bone matrix,attract water through their negatively charged glycosaminoglycan chains.Among these proteoglycans,biglycan(Bgn)and decorin(Dcn)are major subt... Proteoglycans,key components of non-collagenous proteins in the bone matrix,attract water through their negatively charged glycosaminoglycan chains.Among these proteoglycans,biglycan(Bgn)and decorin(Dcn)are major subtypes,yet their distinct roles in bone remain largely elusive.In this study,we utilized single knockout(KO)mouse models and successfully generated double KO(dKO)models despite challenges with low yield.Bgn deficiency,but not Dcn deficiency,decreased trabecular bone mass,with more pronounced bone loss in dKO mice.Low-field nuclear magnetic resonance measurements showed a marked decrease in bound water among all KO groups,especially in Bgn KO and dKO mice.Moreover,both Bgn KO and dKO mice exhibited reduced fracture toughness compared to Dcn KO mice.Dcn was significantly upregulated in Bgn KO mice,while a modest upregulation of Bgn was observed in Dcn KO mice,indicating Bgn’s predominant role in bone.High resolution atomic force microscopy showed decreased in situ permanent energy dissipation and increased elastic modulus in the extrafibrillar matrix of Bgn/Dcn deficient mice,which were diminished upon dehydration.Furthermore,we found that both Bgn and Dcn are indispensable for the activation of ERK and p38 MAPK signaling pathways.Collectively,our results highlight the distinct and indispensable roles of Bgn and Dcn in maintaining bone structure,water retention,and bulk/in situ tissue properties in the bone matrix,with Bgn exerting a predominant influence. 展开更多
关键词 RETENTION TOUGHNESS predominant
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