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Preparation,characterization and photocatalysis performances of superparamagnetic MgFe_(2)O_4@CeO_(2) nanocomposites:Synthesized via an easy and green sol-gel method
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作者 Saeid Taghavi Fardood Fateme Yekke Zare +1 位作者 Farzaneh Moradnia Ali Ramazani 《Journal of Rare Earths》 2025年第4期736-742,I0004,共8页
The characte rization of MgFe_(2)O_(4)@CeO_(2) superparamagnetic nanocomposites was tho roughly investigated using powder X-ray diffraction(XRD),a vibrating sample magnetometer(VSM),scanning electron microscopy(SEM),d... The characte rization of MgFe_(2)O_(4)@CeO_(2) superparamagnetic nanocomposites was tho roughly investigated using powder X-ray diffraction(XRD),a vibrating sample magnetometer(VSM),scanning electron microscopy(SEM),dispersive X-ray analysis(EDX),elemental mapping(MAP),transmission electron microscopy(TEM),Brunauer-Emmett-Teller(BET) and UV-Vis diffuse reflectance spectroscopy(DRS)analyses.The photocatalytic activity of the synthesized samples was evaluated as a novel magnetic nanocatalyst for degrading Congo red(CR) dye in an aqueous solution under visible light at room conditions.The results demonstrate that the efficiency of photocatalytic degradation is higher than that of absorbance and photolysis.The degradation efficiency of photodegradation is 93% within 49% of total organic carbon removal performance.The prepared MgFe_(2)O_(4)@CeO_(2) magnetic nanocomposites(MNCs)can be easily recovered and recycled for five repeated cycles,demonstrating potential extensive efficiency in magnetic nanocomposites in wastewater and water treatment.The nanoscale morphology of MgFe_(2)O_(4)@CeO_(2) MNCs was characterized as spherical,with a size range of 35-40 nm,utilizing SEM and TEM techniques.The saturation magnetization(M_(s)) of the resulting nanocomposites was analyzed by VSM,revealing a value of 3.58 emu/g.Furthermore,the surface area was determined to be 27.194 m^(2)/g using BET analysis,and the band gap was identified as 2.85 eV through DRS analysis. 展开更多
关键词 SUPERPARAMAGNETIC Dye degradation Green synthesis Magnetic nanocomposites Cerium oxide Rare earths
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Landscape restoration in the degraded Afromontane region:A case study of the Bamboutos Mountains landscape in Cameroon
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作者 Tchoutezou Guy Herman ZANGUIM Nyong Princely AWAZI +1 位作者 Lucie Felicite TEMGOUA Martin Ngankam TCHAMBA 《Journal of Mountain Science》 2025年第5期1535-1556,共22页
Existing knowledge on degraded mountain landscapes does not shed sufficient light on the socio-economic and ecological opportunities essential for successful restoration initiatives.To address this knowledge lacuna,a ... Existing knowledge on degraded mountain landscapes does not shed sufficient light on the socio-economic and ecological opportunities essential for successful restoration initiatives.To address this knowledge lacuna,a study was conducted on the Bamboutos Mountains landscape in Cameroon with the main objective being to analyse the opportunities for restoring this landscape in line with local,national and international development goals and to minimise the negative effects of land-use decisions.Following the Restoration Opportunity Assessment Methodology(ROAM)approach,five participatory reflection workshops were organized in the five target clusters of the landscape for data collection.The results of the study led to the development of a restoration map that presents five interventions:grassland management on an area of 4,720 ha currently occupied by shrub savannah;the practice of fruit-based agroforestry on 3,221 ha of agricultural fields;the planting of riparian forests on 451 ha of degraded watercourses;the revegetation and conservation of the Bamboutos Mountains forest reserve,sacred forests and relics of degraded forests on 435 ha of area;and the revegetation of 6 ha of degraded water sources.The carbon stocks vary from 2.66 to 345.15 tC/ha depending on the type of restoration intervention with a total carbon stock of 247,367.45 tC/ha on the 8,834 ha of area to be restored.This presents a very satisfactory economic cost-benefit,because for an investment of USD 5,991,269.84,a gain of USD 100,439,519.13 could be achieved after 20 years,i.e.,an estimated profit of USD 94,448,249.29.These results provide an understanding of the types of restoration interventions possible in this landscape,a solid basis for planning a restoration initiative.The results equally provide guidance on priority areas from a social,economic,and ecological perspective. 展开更多
关键词 Carbon stocks BAMBOO Biodiversity conservation Forest reserves Sacred forests Watershed AGROFORESTRY Western Highlands of Cameroon
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Determinants of COVID-19 vaccine booster hesitancy among outpatients completing the primary scheme in Turkey
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作者 Hakan Tüzün Mehmet AÖzçelik +1 位作者 CansuÖzbaş Mustafa Nİlhan 《Asian Pacific Journal of Tropical Medicine》 2025年第5期225-235,共11页
Objective:To examine the change in COVID-19 booster vaccine hesitancy according to descriptive characteristics,characteristics related to COVID-19,health literacy(HL)skills related to booster dose.Methods:The inclusio... Objective:To examine the change in COVID-19 booster vaccine hesitancy according to descriptive characteristics,characteristics related to COVID-19,health literacy(HL)skills related to booster dose.Methods:The inclusion criterion was the completion of the primary scheme as two doses of COVID-19 vaccine.The study was conducted in January 2022 by applying face-to-face interview technique.Questions regarding HL were used to question the ability of individuals to access,understand,interpret and use information regarding the COVID-19 booster dose in their decisions.Results:A total of 1210 people were included in this study with an mean age of(41.3±16.6)years,and 51.4%were women.In multivariate analysis,hesitation increased in the"moderately concerned"(aOR 2.65,95%CI 1.09-6.45),"slightly concerned"(aOR 3.01,95%CI 1.26-7.19),"not concerned at all”(aOR 5.69,95%CI 2.27-14.28)groups compared to the group“extremely concerned”about COVID-19 transmission.Those with Sinovac-CoronaVac as their most recent vaccine had increased hesitation compared to those with Pfizer-BioNTech(aOR 3.68,95%CI 2.05-6.61).The effect of HL skills including“accessing”,“understanding”,and“appraising”information on hesitation was not statistically significant(P>0.05).HL skill of“applying”was assessed with ability of information to help decision making.Whether the information is helpful for decision-making,the risk of hesitancy increased for those who stated that it"sometimes helps"(aOR 2.55;95%CI 1.31-4.99)and"never helps"(aOR 11.62;95%CI 3.03-44.58)compared to those who stated that it"always helps".Conclusions:The increased propability of hesitation in those less concerned about COVID-19 transmission shows the importance of appropriately guiding individuals'concern levels with a health communication strategy based on risk communication.The fact that the only HL skill with a significant effect in the multivariate model was“applying”,shows the critical role of this skill in influencing behavioral changes. 展开更多
关键词 COVID-19 Vaccine hesitancy Booster hesitancy Health literacy Risk communication
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Comparison of processing speed of NRS-ANN hybrid and ANN models for oil production rate estimation of reservoir under waterflooding
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作者 Paul Theophily Nsulangi Werneld Egno Ngongi +1 位作者 John Mbogo Kafuku Guan Zhen Liang 《Artificial Intelligence in Geosciences》 2025年第2期101-112,共12页
This study compared the predictive performance and processing speed of an artificial neural network(ANN)and a hybrid of a numerical reservoir simulation(NRS)and artificial neural network(NRS-ANN)models in estimating t... This study compared the predictive performance and processing speed of an artificial neural network(ANN)and a hybrid of a numerical reservoir simulation(NRS)and artificial neural network(NRS-ANN)models in estimating the oil production rate of the ZH86 reservoir block under waterflood recovery.The historical input variables:reservoir pressure,reservoir pore volume containing hydrocarbons,reservoir pore volume containing water and reservoir water injection rate used as inputs for ANN models.To create the NRS-ANN hybrid models,314 data sets extracted from the NRS model,which included reservoir pressure,reservoir pore volume containing hy-drocarbons,reservoir pore volume containing water and reservoir water injection rate were used.The output of the models was the historical oil production rate(HOPR in m^(3) per day)recorded from the ZH86 reservoir block.Models were developed using MATLAB R2021a and trained with 25 models in three replicate conditions(2,4 and 6),each at 1000 epochs.A comparative analysis indicated that,for all 25 models,the ANN outperformed the NRS-ANN in terms of processing speed and prediction performance.ANN models achieved an average of R^(2) and MAE of 0.8433 and 8.0964 m^(3)/day values,respectively,while NRS-ANN hybrid models achieved an average of R^(2) and MAE of 0.7828 and 8.2484 m^(3)/day values,respectively.In addition,ANN models achieved a processing speed of 49 epochs/sec,32 epochs/sec,and 24 epochs/sec after 2,4,and 6 replicates,respectively.Whereas the NRS-ANN hybrid models achieved lower average processing speeds of 45 epochs/sec,23 epochs/sec and 20 epochs/sec.In addition,the ANN optimal model outperforms the NRS-ANN model in terms of both processing speed and accuracy.The ANN optimal model achieved a speed of 336.44 epochs/sec,compared to the NRS-ANN hybrid optimal model,which achieved a speed of 52.16 epochs/sec.The ANN optimal model achieved lower RMSE and MAE values of 7.9291 m^(3)/day and 5.3855 m^(3)/day in the validation dataset compared with the hybrid ANS optimal model,which achieved 13.6821 m^(3)/day and 9.2047 m^(3)/day,respectively.The study also showed that the ANN optimal model consistently achieved higher R^(2) values:0.9472,0.9284 and 0.9316 in the training,test and validation data sets.Whereas the NRS-ANN hybrid optimal yielded lower R^(2) values of 0.8030,0.8622 and 0.7776 for the training,testing and validation datasets.The study showed that ANN models are a more effective and reliable tool,as they balance both processing speed and accuracy in estimating the oil production rate of the ZH86 reservoir block under the waterflooding recovery method. 展开更多
关键词 Oil production rate prediction Processing speed of the NRS-ANN and ANN models Performance of the NRS-ANN and ANN models Artificial Neural Network(ANN) Hybrid model of NRS and ANN
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Newly isolated terpenoids(covering 2019-2024)from Aspergillus species and their potential for the discovery of novel antimicrobials
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作者 Olusesan Ojo Idris Njanje +3 位作者 Dele Abdissa Tarryn Swart Roxanne L.Higgitt Rosemary A.Dorrington 《Natural Products and Bioprospecting》 2025年第2期111-142,共32页
The rapid emergence of drug-resistant microbial pathogens has posed challenges to global health in the twenty-first century.This development has significantly made most antibiotics ineffective in the treatment of infe... The rapid emergence of drug-resistant microbial pathogens has posed challenges to global health in the twenty-first century.This development has significantly made most antibiotics ineffective in the treatment of infections they cause,resulting in increasing treatment costs and annual death rates.To address the challenge posed by these pathogens,we explore the potential of secondary metabolites from Aspergillus species as a source of new and effective therapeutic agents to treat drug-resistant infections.Terpenoids,a distinct group of natural products,are extensively distributed in plants and fungi,and have been attributed with significant antibacterial,anticancer,and antiviral activities.In this review,we present an overview of Aspergillus species,and review the novel terpenoids isolated from them from 2019 to April 2024,highlighting anti-infective activity against members of the ESKAPE pathogens.We further focus on the strategies through which the structural framework of these new terpenoids could be modified and/or optimized to feed a pipeline of new lead compounds targeting microbial pathogens.Overall,this review provides insight into the therapeutic applications of terpenoids sourced from Aspergillus species and the potential for the discovery of new compounds from these fungi to combat antimicrobial resistance. 展开更多
关键词 Antimicrobial resistance ESKAPE pathogens FUNGI Secondary metabolites Anti-infective activities
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Groundwater geochemical evolution,origin and quality in the Lower Pra Basin,Ghana:Insights from hydrogeochemistry,multivariate statistical analysis,mineral saturation indices,stable isotopes(δ^(2)H and δ^(18)O)and geostatistical analysis
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作者 Samuel Y.Ganyaglo Joel Y.Binyiako +7 位作者 Emmanuel M.Teye Abass Gibrilla Dickson Abdul-Wahab Samuel Edusei Paulina Amponsah Courage D.Egbi Samuel B.Dampare Ebenezer Aquisman Asare 《Acta Geochimica》 2025年第2期348-372,共25页
In many places across the globe,including the Wassa District of Ghana,groundwater provides a significant supply of water for various purposes.Understanding the groundwater origin and hydrogeochemical processes control... In many places across the globe,including the Wassa District of Ghana,groundwater provides a significant supply of water for various purposes.Understanding the groundwater origin and hydrogeochemical processes controlling the groundwater chemistry is a major step in the sustainable management of the aquifers.A total of 29groundwater samples were collected and analysed.Ionic ratio graphs,multivariate statistical analysis,mineral saturation indices,stable isotopes,and geostatistics methods were used to examine the sources and the quality of the groundwater.The findings describe the water types in the district as Ca-Mg-HCO_(3)-Cl,Ca-Na-HCO_(3),Na-Ca-HCO_(3),Ca-Na-HCO_(3)-Cl,Na-Ca-HCO_(3)-Cl,mix water type,NaHCO_(3)-Cl,with possible evolution to Ca-Na-Cl-HCO_(3),and Na-Ca-Cl-HCO_(3).According to the IEWQI for drinking water,around 53.6% of the samples have good quality,whereas 10.7% have very low-quality groundwater.Only 3.45% of the samples are suitable to use for irrigation without treatment,whereas 41.4% are somewhat safe with minimal treatment.Water-rock interactions,including the dissolution and weathering of silicate minerals,cation exchange processes,and human activities like mining andquarrying,are some of the main factors influencing groundwater chemistry.Principal component analysis revealed that groundwater chemistry is influenced by a combination of natural and anthropogenic sources.The APCs-MLR receptor model quantifies the factors that play important roles in groundwater salinization,including mineral dissolution and weathering(19.4%),localised Cd(16%),Ni(14.6%),Pb(12.8%),and Fe(11.4%)contamination from urbanisation while unidentified sources of pollution account for about 26.0%.The stable isotopes revealed groundwater is of meteoric origin and water-rock interaction the major mechanism for groundwater mineralization.The results of this research highlight the need of implementing an integrated strategy for managing and accessing groundwater quality. 展开更多
关键词 GROUNDWATER Integrated approaches Stable isotopes Hydrochemical facies Water-rock interaction Quality assessment Empirical Bayesian kriging
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Towards eradicating antibiotic-resistant bacteria: synthesis and antibacterial activities of substituted N-(2-nitrophenyl)pyrrolidine-and piperidine-2-carboxylic acids
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作者 Jocelyn A.Odusami Monisola I.Ikhile +7 位作者 Marthe C.D.Fotsing Idris A.O.lasupo Josephat U.Izunobi Elizabeth O.Bamgbade Thierry Y.Fonkui Olayinka T.Asekun Oluwole B.Familoni Derek T.Ndinteh 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第10期704-715,共12页
Antibacterial resistance is a source of great concern in the effective prevention and treatment of infections caused by bacteria,making the development of requisite therapeutics a major challenge.N-(Nitrophenyl)cycloa... Antibacterial resistance is a source of great concern in the effective prevention and treatment of infections caused by bacteria,making the development of requisite therapeutics a major challenge.N-(Nitrophenyl)cycloamino acids are important compounds in the synthesis of poly-condensed nitrogen-containing heterocycles with marked activities in many biological systems.A series of substituted N-(o-nitrophenyl)cycloamino-2-carboxylic acids 3a–3g were synthesized via the condensation reaction of substituted o-halogenonitrobenzenes with L-proline 2a and D,L-pipecolinic acid 2b,under refluxing alcoholic basic conditions in excellent yields.The synthesized compounds were characterised by FT-IR,(1H&13C)NMR,UV-Vis,mass spectroscopy and elemental analysis.Their antibacterial activities were evaluated against five Gram-positive and five Gram-negative bacterial strains using the broth micro-dilution procedure.The antibacterial activities of the synthesized compounds were compared with streptomycin and nalidixic acid as standard antibiotic drugs.The minimum inhibitory concentration(MIC)values of compounds 3a–3g revealed good antibacterial activities against the tested microorganisms.Compounds 3a–3g were more potent than nalidixic acid against Enterococcus faecalis,Mycobacterium smegmatis,Escherichia coli and Proteus vulgaris and also more potent than streptomycin against Enterobacter cloacae and Staphylococcus aureus.Compounds 3a,3c and 3g displayed the highest antibacterial potency with an MIC value of 15.6μg/mL against E.cloacae,E.faecalis and P.mirabilis,respectively.These results indicated that these aryl cycloamino acids with antibacterial activities had potential applications as substitutes for antimicrobial peptide antibiotics,which are not susceptible to bacterial resistance,to solve the problem of drug resistance. 展开更多
关键词 Antibiotics Bacteria Cyclic amino ACIDS o-Halogenonitrobenzene
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A general viscoelastic foundation model for vibration analysis of functionally graded sandwich plate with auxetic core
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作者 Mofareh Hassan Ghazwani Ali Alnujaie Pham Van Vinh 《Defence Technology(防务技术)》 2025年第4期40-58,共19页
This study presents a significant advancement in the vibration analysis of functionally graded sandwich plates with auxetic cores by introducing a general viscoelastic foundation model that more accurately reflects th... This study presents a significant advancement in the vibration analysis of functionally graded sandwich plates with auxetic cores by introducing a general viscoelastic foundation model that more accurately reflects the complex interactions between the plate and the foundation.The novelty of this study is that the proposed viscoelastic foundation model incorporates elastic and damping effects in both the Winkler and Pasternak layers.To develop the theoretical framework for this analysis,the higher-order shear deformation theory is employed,while Hamilton's principle is used to derive the governing equations of motion.The closed-form solution is used to determine the damped vibration behaviors of the sandwich plates.The precision and robustness of the proposed mathematical model are validated through several comparison studies with existing numerical results.A detailed parametric study is conducted to investigate the influence of various parameters,including the elastic and damping coefficients of the foundation,the material gradation,and the properties of the auxetic core on the vibration behavior of the plates.The numerical results provide new insights into the vibration characteristics of sandwich plates with auxetic cores resting on viscoelastic foundation,highlighting the significant role of the two damping coefficients and auxetic cores in the visco-vibration behavior of the plates. 展开更多
关键词 Damped vibration Viscoelastic foundation Sandwich plates Auxetic core Honeycomb core Negative Poisson's ratio
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Crude extracts from Diospyros gilletii stem bark attenuate Shigella flexneri-induced diarrhea in mice
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作者 Bijou-Lafortune Noumboue Kouamou Boniface Pone Kamdem +6 位作者 Vincent Ngouana Tashie Evangeline Ngwanguong Jaurès Marius Tsakem Nangap Listone Monelle Nzeye Ngameni Yanick Kevin Dongmo Melogmo Paul Keilah Lunga Fabrice Fekam Boyom 《Asian Pacific Journal of Tropical Biomedicine》 2025年第6期219-228,I0002-I0006,共15页
Objective:To evaluate the anti-shigellosis activity of the hydroethanol extract of Diospyros gilletii(D.gilletii)stem bark in Shigella flexneri(S.flexneri)-induced diarrheal mice.Methods:The hydroethanolic extract was... Objective:To evaluate the anti-shigellosis activity of the hydroethanol extract of Diospyros gilletii(D.gilletii)stem bark in Shigella flexneri(S.flexneri)-induced diarrheal mice.Methods:The hydroethanolic extract was obtained by maceration of D.gilletii stem bark in 70%hydroethanol(water꞉ethanol;30꞉70,v/v)solution.Then,mice pretreated with cyclophosphamide for immunosuppression were administered orally with an inoculum containing S.flexneri,and subsequently treated with 100,200,and 400 mg/kg of the hydroethanol extracts for 10 days.The bacterial colonies were enumerated and hematological and biochemical parameters were determined.Serum pro-inflammatory mediators including IL-1β,IL-18,and TNF-α,and nitric oxide levels were quantified by ELISA.Histological analyses of the kidney,liver,and colon were also conducted.Results:Treatment with 200 and 400 mg/kg of the hydroethanolic extracts markedly inhibited the growth of S.flexneri.Moreover,treatment with D.gilletii extract downregulated the levels of IL-1β,IL-18,and TNF-α,and restored hematological and biochemical parameters as well as histological architecture of the colon,liver,and kidneys.Additionally,the oral administration of 2000 mg/kg D.gilletii extract did not induce any sign of toxicity,with a median lethal dose greater than 2000 mg/kg.Conclusions:D.gilletii extract demonstrates the anti-shigellosis effects in S.flexneri-induced diarrheal mice,supporting the traditional use of this plant in treating diarrhea. 展开更多
关键词 Diospyros gilletti Shigella flexneri DIARRHEA Pro-inflammatory cytokines Acute toxicity SHIGELLOSIS
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Analyzing the barriers to blockchain adoption in supply chain finance using an integrated interval‑valued Fermatean fuzzy RAFSI model
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作者 Weizhong Wang Yu Chen +3 位作者 Yi Wang Muhammet Deveci Amer Al‑Hinai Seifedine Kadry 《Financial Innovation》 2025年第1期213-251,共39页
Many attempts have been made to identify barriers to blockchain adoption in supply chain;however,barriers to blockchain adoption in supply chain finance(SCF)are underexplored.This study prioritizes barriers to blockch... Many attempts have been made to identify barriers to blockchain adoption in supply chain;however,barriers to blockchain adoption in supply chain finance(SCF)are underexplored.This study prioritizes barriers to blockchain adoption in SCF and evaluates the barrier level of each alternative participant.We propose an integrated decision model to prioritize the barriers and evaluate their levels of alternative participants.To determine the barriers,we conducted a literature review.We then introduce an integrated weight calculation method by combining interval-valued Fermatean fuzzy(IVFF)-optimistic-pessimistic-utility values-based and IVFF-RS(ranking sum)methods to determine the barrier weights.To evaluate the barrier level of each alternative participant in SCF,the integrated IVFF-RAFSI(Ranking of Alternatives through Functional Mapping of Criterion Subintervals into a Single Interval)model is presented to rank the barrier,which uses a power-weighted aggregation operator to fuse experts’opinions.A case study demonstrates the practicality of the integrated IVFF-RAFSI model.The results show that uncertain and competitive markets(weighted at 0.0676)are the most significant barriers.This finding also suggests that small and medium-sized processing enterprises have the highest barriers to blockchain adoption.Sensitivity and comparative analyses validate the steadiness and competency of the proposed model.These results indicate that the proposed methodology provides a systematic technique for analyzing barriers to blockchain applications in SCF. 展开更多
关键词 Blockchain RAFSI model Supply chain finance Interval-valued Fermatean fuzzy
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Development of bubble point pressure and oil formation volume factor models using pressure-volume-temperature data
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作者 Grant Charles Mwakipunda Allou KoffiFranck Kouassi +3 位作者 Mbula Ngoy Nadege Melckzedeck Michael Mgimba Mbega Ramadhani Ngata Long Yu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7127-7146,共20页
The Pressure-Volume-Temperature(PVT)properties of crude oil are typically determined through laboratory analysis during the early phases of exploration and fielddevelopment.However,due to extensive data required,time-... The Pressure-Volume-Temperature(PVT)properties of crude oil are typically determined through laboratory analysis during the early phases of exploration and fielddevelopment.However,due to extensive data required,time-consuming nature,and high costs,laboratory methods are often not preferred.Machine learning,with its efficiencyand rapid convergence,has emerged as a promising alternative for PVT properties estimation.This study employs the modified particle swarm optimization-based group method of data handling(PSO-GMDH)to develop predictive models for estimating both the oil formation volume factor(OFVF)and bubble point pressure(P_(b)).Data from the Mpyo oil fieldin Uganda were used to create the models.The input parameters included solution gas-oil ratio(R_(s)),oil American Petroleum Institute gravity(API),specificgravity(SG),and reservoir temperature(T).The results demonstrated that PSO-GMDH outperformed backpropagation neural networks(BPNN)and radial basis function neural networks(RBFNN),achieving higher correlation coefficientsand lower prediction errors during training and testing.For OFVF prediction,PSO-GMDH yielded a correlation coefficient(R)of 0.9979(training)and 0.9876(testing),with corresponding root mean square error(RMSE)values of 0.0021 and 0.0099,and mean absolute error(MAE)values of 0.00055 and 0.00256,respectively.For P_(b)prediction,R was 0.9994(training)and 0.9876(testing),with RMSE values of 6.08 and 8.26,and MAE values of 1.35 and 2.63.The study also revealed that R_(s)significantlyimpacts OFVF and P_(b)predictions compared to other input parameters.The models followed physical laws and remained stable,demonstrating that PSO-GMDH is a robust and efficientmethod for predicting OFVF and P_(b),offering a time and cost-effective alternative. 展开更多
关键词 Oil formation volume factor Bubble point pressure Pressure-volume-temperature(PVT) PROPERTIES Machine learning
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The Youth Fitness International Test(YFIT)battery for monitoring and surveillance among children and adolescents:A modified Delphi consensus project with 169 experts from 50 countries and territories
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作者 Francisco B.Ortega Kai Zhang +23 位作者 Cristina Cadenas-Sanchez Mark S.Tremblay Gregor Jurak Grant R,Tomkinson Jonatan R.Ruiz Katja Keller Christine Delisle Nystrom Jennifer MSacheck Russell Pate Kathryn LWeston Tetsuhiro Kidokoro Eric TPoon Lucy-Joy M.Wachira Ronald Ssenyonga Thayse Natacha Q.F.Gomes Carlos Cristi-Montero Brooklyn J.Fraser Claudia Niessner Vincent O.Onywera Yang Liu Li-Lin Liang Stephanie A.Prince Justin J.Lang the Delphi Fitness Expert Group 《Journal of Sport and Health Science》 2025年第4期48-63,共16页
Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit interna... Background:Physicalfitness in childhood and adolescence is associated with a variety of health outcomes and is a powerful marker of current and future health.However,inconsistencies in tests and protocols limit international monitoring and surveillance.The objective of the study was to seek international consensus on a proposed,evidence-informed,Youth Fitness International Test(YFIT)battery and protocols for health monitoring and surveillance in children and adolescents aged 618 years.Methods:We conducted an international modified Delphi study to evaluate the level of agreement with a proposed,evidence-based,YFIT of core health-relatedfitness tests and protocols to be used worldwide in 6-to 18-year-olds.This proposal was based on previous European and North American projects that systematically reviewed the existing evidence to identify the most valid,reliable,health-related,safe,and feasiblefitness tests to be used in children and adolescents aged 618 years.We designed a single-panel modified Delphi study and invited 216 experts from all around the world to answer this Delphi survey,of whom one-third are from low-to-middle income countries and one-third are women.Four experts were involved in the piloting of the survey and did not participate in the main Delphi study to avoid bias.We pre-defined an agreement of 80%among the expert participants to achieve consensus.Results:We obtained a high response rate(78%)with a total of 169fitness experts from 50 countries and territories,including 63 women and 61 experts from low-or middle-income countries/territories.Consensus(>85%agreement)was achieved for all proposed tests and protocols,supporting the YFIT battery,which includes weight and height(to compute body mass index as a proxy of body size/composition),the 20-m shuttle run(cardiorespiratoryfitness),handgrip strength,and standing long jump(muscularfitness).Conclusion:This study contributes to standardizingfitness tests and protocols used for research,monitoring,and surveillance across the world,which will allow for future data pooling and the development of international and regional sex-and age-specific reference values,health-related cut-points,and a global picture offitness among children and adolescents. 展开更多
关键词 FITNESS Experts DELPHI Protocols Youth Fitness International Test
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Spatial and temporal variability of daily precipitation in Haihe River basin, 1958-2007 被引量:19
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作者 CHU Jianting XIA Jun +2 位作者 XU Chongyu LI Lu WANG Zhonggen 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期248-260,共13页
The seasonal variability and spatial distribution of precipitation are the main cause of flood and drought events. The study of spatial distribution and temporal trend of precipitation in river basins has been paid mo... The seasonal variability and spatial distribution of precipitation are the main cause of flood and drought events. The study of spatial distribution and temporal trend of precipitation in river basins has been paid more and more attention. However, in China, the precipitation data are measured by weather stations (WS) of China Meteorological Administration and hydrological rain gauges (RG) of national and local hydrology bureau. The WS data usually have long record with fewer stations, while the RG data usually have short record with more stations. The consistency and correlation of these two data sets have not been well understood. In this paper, the precipitation data from 30 weather stations for 1958-2007 and 248 rain gauges for 1995-2004 in the Haihe River basin are examined and compared using linear regression, 5-year moving average, Mann-Kendall trend analysis, Kolmogorov-Smirnov test, Z test and F test methods. The results show that the annual precipitation from both WS and RG records are normally distributed with minor difference in the mean value and variance. It is statistically feasible to extend the precipitation of RG by WS data sets. Using the extended precipitation data, the detailed spatial distribution of the annual and seasonal precipitation amounts as well as their temporal trends are calculated and mapped. The various distribution maps produced in the study show that for the whole basin the precipitation of 1958-2007 has been decreasing except for spring season. The decline trend is significant in summer, and this trend is stronger after the 1980s. The annual and seasonal precipitation amounts and changing trends are different in different regions and seasons. The precipitation is decreasing from south to north, from coastal zone to inland area. 展开更多
关键词 climate change spatial and temporal variability of precipitation Mann-Kendall method Kolmogorov-Smirnov test Z test F test Haihe River basin
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THE BEHAVIOR OF TWO PARALLEL SYMMETRIC PERMEABLE CRACKS IN PIEZOELECTRIC MATERIALS 被引量:3
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作者 ZHOU Zhen-gong(周振功) +1 位作者 WANG Biao(王彪) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1357-1366,共10页
The behavior of two parallel symmetric cracks in piezoelectric materials under anti-plane shear loading was studied by the Schmidt method for the permeable crack face conditions. By using the Fourier transform, the pr... The behavior of two parallel symmetric cracks in piezoelectric materials under anti-plane shear loading was studied by the Schmidt method for the permeable crack face conditions. By using the Fourier transform, the problem can be solved with two pairs of dual integral equations in which the unknown variable is the jump of the diplacement across the crack surfaces. These equations were solved using the Schmidt method. The results show that the stress and the electric displacement intensity factors of cracks depend on the geometry of the crack. Contrary to the impermeable crack surface condition solution, it is found that the electric displacement intensity factors for the permeable crack surface conditions are much smaller than the results for the impermeable crack surface conditions. 展开更多
关键词 piezoelectric material parallel crack Schmidt method dual-integral equation stress and electric displacement intensity factors
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Effects of porosity heterogeneity on chemical dissolution-front instability in fluid-saturated rocks 被引量:4
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作者 ZHAO Chong-bin Peter SCHAUBS Bruce HOBBS 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期720-725,共6页
Homogeneity and heterogeneity are two totally different concepts in nature.At the particle length scale,rocks exhibit strong heterogeneity in their constituents and porosities.When the heterogeneity of porosity obeys ... Homogeneity and heterogeneity are two totally different concepts in nature.At the particle length scale,rocks exhibit strong heterogeneity in their constituents and porosities.When the heterogeneity of porosity obeys the random uniform distribution,both the mean value and the variance of porosities in the heterogeneous porosity field can be used to reflect the overall heterogeneous characteristics of the porosity field.The main purpose of this work is to investigate the effects of porosity heterogeneity on chemical dissolution front instability in fluid-saturated rocks by the computational simulation method.The related computational simulation results have demonstrated that:1) since the propagation speed of a chemical dissolution front is inversely proportional to the difference between the final porosity and the mean value of porosities in the initial porosity field,an increase in the extent of the porosity heterogeneity can cause an increase in the mean value of porosities in the initial porosity field and an increase in the propagation speed of the chemical dissolution front.2) An increase in the variance of porosities in the initial porosity field can cause an increase in the instability probability of the chemical dissolution front in the fluid-saturated rock.3) The greater the mean value of porosities in the initial porosity field,the quicker the irregular morphology of the chemical dissolution front changes in the supercritical chemical dissolution systems.This means that the irregular morphology of a chemical dissolution front grows quicker in a porosity field of heterogeneity than it does in that of homogeneity when the chemical dissolution system is at a supercritical stage. 展开更多
关键词 porosity heterogeneity chemical dissolution front instability computational simulation porous rocks
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In vitro activities of acetonic extracts from leaves of three forage legumes(Calliandra calotyrsus,Gliricidia sepium and Leucaena diversifolia) on Haemonchus contortus 被引量:2
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作者 Wabo Pone J Kenne Tameli Florence +2 位作者 Mpoame Mbida Pamo Tedonkeng E Bilong Bilong CF 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第2期125-128,共4页
Objective:To assess ovicidal activity of three acetonic extracts from the leaves of three forage legume,Calliandra calotyrsus(C.calotyrsus),Gliricidia sepium(G.sepium) and Leucaena diversifolia(L.diversifolia) in vitr... Objective:To assess ovicidal activity of three acetonic extracts from the leaves of three forage legume,Calliandra calotyrsus(C.calotyrsus),Gliricidia sepium(G.sepium) and Leucaena diversifolia(L.diversifolia) in vitro on Haemonchus contortus(H.contortus).Methods:Eggs were exposed for 24 hours to five different concentrations(0.075,0.15,0.3,0.6 and 1.25 mg/mL) of acetonic extracts at room temperature(24℃).Distilled water and 0.4%Tween were used in the bioassay as negative controls.Results:The later did not affect embryonation and egg hatching of H.contortus.Conversively,significant effects were obtained with the acetonic extracts of leaves of all three plants and the maximum activity was observed with the highest concentration (1.25 mg/mL).The acetonic extract of G.sepium was found to be more active(2.9%and 0.0% for embryonation and egg hatching,respectively) than the other substances 16.5%and 33.5%, respectively for C.calothyrsus,33.7%and 33.3%,respectively for L diversifolia.Conclusions: These results suggest that the three forage legumes do possess ovicidal properties and further studies on larvae should be carried out. 展开更多
关键词 Extract CALLIANDRA calotyrsus GLIRICIDIA sepium LEUCAENA diversifolia MEBENDAZOLE HAEMONCHUS contortus Cameroon
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Surface nanostructure modification of Al substrates by N^+ ion implantation and their corrosion inhibition 被引量:2
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作者 FatemeABDI HadiSAVALONI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第3期701-710,共10页
The influence of implantation of N+ions of different energies on the nanostructure of7049Al substrates and the corrosioninhibition of produced Al samples in a3.5%NaCl solution was studied.The X-ray diffraction(XRD)res... The influence of implantation of N+ions of different energies on the nanostructure of7049Al substrates and the corrosioninhibition of produced Al samples in a3.5%NaCl solution was studied.The X-ray diffraction(XRD)results confirmed the formationof AlN as a result of N+ion implantation.The atomic force microscope(AFM)results showed that grains of larger scale are formedby increasing N+energy which can be due to heat accumulation in the sample during implantation causing higher rate of diffusion inthe sample,hence decreasing the number of defects.Corrosion resistance of the samples was studied by the electrochemicalimpedance spectroscopy(EIS)measurements.Results showed that corrosion resistance of implanted Al increases with increasing N+ion energy.The equivalent circuits for the N+implanted Al samples with different energies were obtained,using the EIS data whichshowed strong dependence of the equivalent circuit elements on the surface morphology of the samples.Finally,the relationshipbetween corrosion inhibition and equivalent circuit elements was investigated. 展开更多
关键词 ion implantation ALUMINUM CORROSION electrochemical impedance spectroscopy equivalent circuit
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Petrographic and SHRIMP Studies of Zircons fromthe Caledonian Xiongdian Eclogite, NorthwesternDabie Mountains 被引量:4
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作者 I.S.WILLIAMS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第4期766-773,共8页
The Xiongdian eclogite occurring in the Sujiahe tectonic melange zone at Luoshan County, Henan Province, in the western Dabie Mountains, is typical high-pressure (HP)-ultrahigh-pressure (UHP) and medium-temperature ec... The Xiongdian eclogite occurring in the Sujiahe tectonic melange zone at Luoshan County, Henan Province, in the western Dabie Mountains, is typical high-pressure (HP)-ultrahigh-pressure (UHP) and medium-temperature eclogite. The occurrence, internal texture and surface characteristics of zircons in eclogite were studied rather systematically petrographically combined with the cathodoluminescence (CL) and scanning electron microscope (SEM) methods. Zircons are mainly hosted in garnet and other metamorphic minerals with sharp boundaries, have a multifaceted morphology and are homogeneous or exhibit a metamorphic growth texture in the interior, thus indicating that they are the product of metamorphism. SHRIMP analyses give zircon 206Pb/238U ages of 335 to 424 Ma and show a certain degree of radiogenic Pb loss; therefore it may be inferred that the age of 424? Ma represents the minimum age of a HP-UHP metamorphic age. From the above analyses coupled with previous Sm-Nd, 40Ar-39Ar, U-Pb and 207Pb/206Pb age data, it is suggested that the peak metamorphic age of the Xiongdian eclogite should be between 424 and 480 Ma. This study further validate the view of the existence of a Caledonian HP-UHP metamorphic event in the western Dabie Mountains. 展开更多
关键词 Dabie Mountains CALEDONIAN ECLOGITE SHRIMP analysis
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Modelling Impact of Dredging and Dumping in Ebb-Flood Channel Systems 被引量:2
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作者 HIBMA A WANG Z B +1 位作者 STIVE M J F Vriend H J de 《Transactions of Tianjin University》 EI CAS 2008年第4期271-281,共11页
For a channel-shoal system in a funnel-shaped basin the impact of dredging and dumping is investigated using a complex process-based model. First, the residual flow and sediment transport circulations are analysed for... For a channel-shoal system in a funnel-shaped basin the impact of dredging and dumping is investigated using a complex process-based model. First, the residual flow and sediment transport circulations are analysed for the channel-shoal pattern, which has emerged after a longterm model simulation. Results are compared to the Western Scheldt estuary, which forms the inspiration for this study. Subsequently, different dredge and dump scenarios are modelled, according to a conceptual model, in which ebb- and flood-channels and enclosed shoals form morphodynamic units (cells) with their own sediment circulation. Model results show that dumping sediment in a channel further reduces the channel depth and induces erosion in the opposite channel, which enhances tilting of the cross-section of the cell and eventually can lead to the degeneration of a multiple channel system into a single channel. The impact of different dredging and dumping cases agrees with results from a stability analysis. This means that this type of model applied to a realistic geometry can potentially be used for better prediction of the impact of human interventions. 展开更多
关键词 estuaries MORPHOLOGY numerical model channel SHOAL DREDGING DUMPING
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The impact of emergency department length of stay on the outcomes of trauma patients requiring hospitalization: a retrospective observational study 被引量:2
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作者 Ahmed Faidh Ramzee Ayman El-Menyar +7 位作者 Mohammad Asim Ahad Kanbar Khalid Ahmed Bahaa Daoud Saji Mathradikkal Ahmad Kloub Hassan Al-Thani Sandro Rizoli 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第2期96-105,共10页
BACKGROUND: We aimed to explore the impact of the emergency department length of stay(EDLOS) on the outcome of trauma patients.METHODS: A retrospective study was conducted on all trauma patients requiring hospitalizat... BACKGROUND: We aimed to explore the impact of the emergency department length of stay(EDLOS) on the outcome of trauma patients.METHODS: A retrospective study was conducted on all trauma patients requiring hospitalization between 2015 and 2019. Patients were categorized into 4 groups based on the EDLOS(<4 h, 4–12 h,12–24 h, and >24 h). Data were analyzed using Chi-square test(categorical variables), Student’s t-test(continuous variables), correlation coefficient, analysis of variance and multivariate logistic regression analysis for identifying predictors of short EDLOS and hospital mortality.RESULTS: The study involved 7,026 patients with a mean age of 32.1±15.6 years. Onefifth of patients had a short EDLOS(<4 h) and had higher level trauma team T1 activation(TTA-1), higher Injury Severity Score(ISS), higher shock index(SI), and more head injuries than the other groups(P=0.001). Patients with an EDLOS >24 h were older(P=0.001) and had more comorbidities(P=0.001) and fewer deaths(P=0.001). Multivariate regression analysis showed that the predictors of short EDLOS were female gender, GCS, SI, hemoglobin level, ISS, and blood transfusion. The predictors of mortality were TTA-1(odds ratio [OR]=4.081, 95%CI: 2.364–7.045), head injury(OR=3.920, 95%CI: 2.413–6.368), blood transfusion(OR=2.773, 95%CI: 1.668–4.609), SI(OR=2.132, 95%CI: 1.364–3.332), ISS(OR=1.077, 95%CI: 1.057–1.096), and age(OR=1.040, 95%CI: 1.026–1.054). CONCLUSIONS: Patients with shorter EDLOS had different baseline characteristics and hospital outcomes compared with patients with longer EDLOS. Patients with prolonged EDLOS had better outcomes;however, the burden of prolonged boarding in the ED needs further elaboration. 展开更多
关键词 Emergency department Length of stay TRAUMA Management OUTCOMES Trauma activation criteria
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