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Fluidization and Transport of Vibrated Granular Matter:A Review of Landmark and Recent Contributions 被引量:1
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作者 Peter Watson Sebastien Vincent Bonnieu Marcello Lappa 《Fluid Dynamics & Materials Processing》 EI 2024年第1期1-29,共29页
We present a short retrospective review of the existing literature about the dynamics of(dry)granular matter under the effect of vibrations.The main objective is the development of an integrated resource where vital i... We present a short retrospective review of the existing literature about the dynamics of(dry)granular matter under the effect of vibrations.The main objective is the development of an integrated resource where vital information about past findings and recent discoveries is provided in a single treatment.Special attention is paid to those works where successful synthetic routes to as-yet unknown phenomena were identified.Such landmark results are analyzed,while smoothly blending them with a history of the field and introducing possible categorizations of the prevalent dynamics.Although no classification is perfect,and it is hard to distillate general properties out of specific observations or realizations,two possible ways to interpret the existing results are defined according to the type of forcing or the emerging(ensuing)regime of motion.In particular,first results concerning the case where vibrations and gravity are concurrent(vertical shaking)are examined,then the companion situation with vibrations perpendicular to gravity(horizontal shaking)is described.Universality classes are introduced as follows:(1)Regimes where sand self-organizes leading to highly regular geometrical“pulsating”patterns(thin layer case);(2)Regimes where the material undergoes“fluidization”and develops an internal multicellular convective state(tick layers case);(3)Regimes where the free interface separating the sand from the overlying gas changes inclination or develops a kind a patterned configuration consisting of stable valleys and mountains or travelling waves;(4)Regimes where segregation is produced,i.e.,particles of a given size tend to be separated from the other grains(deep containers).Where possible,an analogy or parallelism is drawn with respect to the companion field of fluid-dynamics for which the assumption of“continuum”can be applied. 展开更多
关键词 Granular materials vibrations FLUIDIZATION FLOWABILITY symmetry breaking
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Task Offloading in Edge Computing Using GNNs and DQN
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作者 Asier Garmendia-Orbegozo Jose David Nunez-Gonzalez Miguel Angel Anton 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2649-2671,共23页
In a network environment composed of different types of computing centers that can be divided into different layers(clod,edge layer,and others),the interconnection between them offers the possibility of peer-to-peer t... In a network environment composed of different types of computing centers that can be divided into different layers(clod,edge layer,and others),the interconnection between them offers the possibility of peer-to-peer task offloading.For many resource-constrained devices,the computation of many types of tasks is not feasible because they cannot support such computations as they do not have enough available memory and processing capacity.In this scenario,it is worth considering transferring these tasks to resource-rich platforms,such as Edge Data Centers or remote cloud servers.For different reasons,it is more exciting and appropriate to download various tasks to specific download destinations depending on the properties and state of the environment and the nature of the functions.At the same time,establishing an optimal offloading policy,which ensures that all tasks are executed within the required latency and avoids excessive workload on specific computing centers is not easy.This study presents two alternatives to solve the offloading decision paradigm by introducing two well-known algorithms,Graph Neural Networks(GNN)and Deep Q-Network(DQN).It applies the alternatives on a well-known Edge Computing simulator called PureEdgeSimand compares them with the two defaultmethods,Trade-Off and Round Robin.Experiments showed that variants offer a slight improvement in task success rate and workload distribution.In terms of energy efficiency,they provided similar results.Finally,the success rates of different computing centers are tested,and the lack of capacity of remote cloud servers to respond to applications in real-time is demonstrated.These novel ways of finding a download strategy in a local networking environment are unique as they emulate the state and structure of the environment innovatively,considering the quality of its connections and constant updates.The download score defined in this research is a crucial feature for determining the quality of a download path in the GNN training process and has not previously been proposed.Simultaneously,the suitability of Reinforcement Learning(RL)techniques is demonstrated due to the dynamism of the network environment,considering all the key factors that affect the decision to offload a given task,including the actual state of all devices. 展开更多
关键词 Edge computing edge offloading fog computing task offloading
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Sn nucleation and growth from Sn(II)dissolved in ethylene glycol:Electrochemical behavior and temperature effect
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作者 Kiem Van DO Hieu Van NGUYEN Tu Manh LE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第8期2714-2732,共19页
Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks obs... Thermodynamic and kinetic aspects of Sn nucleation and growth processes onto a glassy carbon electrode from SnCl2·2H2O dissolved in ethylene glycol solutions were studied.Typical reduction and oxidation peaks observed in voltammograms have demonstrated the capability of ethylene glycol solutions to electrodeposit Sn.The temperature-dependence of diffusion coefficient values derived from potentiodynamic and potentiostatic studies helped to determine and validate estimations of the activation energy for Sn(II)bulk diffusion.Chronoamperometric results have identified that,the suitable model to describe the early stage of Sn electrodeposition could be composed of Sn three-dimensional nucleation and diffusion-controlled growth and water reduction contributions,which was duly validated by theoretical and experimental approaches.From the model,typical kinetic parameters such as the nucleation frequency of Sn(A),number density of Sn nuclei(N0),and diffusion coefficient of Sn(II)ions(D),were determined.The presence of Sn nuclei with excellent quality and their structures were verified using SEM,EDX,and XRD techniques. 展开更多
关键词 SN NUCLEATION growth ethylene glycol nucleation kinetics ELECTRODEPOSITION
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Data-driven diagnosis of high temperature PEM fuel cells based on the electrochemical impedance spectroscopy: Robustness improvement and evaluation
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作者 Dan Yu Xingjun Li +2 位作者 Samuel Simon Araya Simon Lennart Sahlin Vincenzo Liso 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期544-558,共15页
Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a cr... Utilizing machine learning techniques for data-driven diagnosis of high temperature PEM fuel cells is beneficial and meaningful to the system durability. Nevertheless, ensuring the robustness of diagnosis remains a critical and challenging task in real application. To enhance the robustness of diagnosis and achieve a more thorough evaluation of diagnostic performance, a robust diagnostic procedure based on electrochemical impedance spectroscopy (EIS) and a new method for evaluation of the diagnosis robustness was proposed and investigated in this work. To improve the diagnosis robustness: (1) the degradation mechanism of different faults in the high temperature PEM fuel cell was first analyzed via the distribution of relaxation time of EIS to determine the equivalent circuit model (ECM) with better interpretability, simplicity and accuracy;(2) the feature extraction was implemented on the identified parameters of the ECM and extra attention was paid to distinguishing between the long-term normal degradation and other faults;(3) a Siamese Network was adopted to get features with higher robustness in a new embedding. The diagnosis was conducted using 6 classic classification algorithms—support vector machine (SVM), K-nearest neighbor (KNN), logistic regression (LR), decision tree (DT), random forest (RF), and Naive Bayes employing a dataset comprising a total of 1935 collected EIS. To evaluate the robustness of trained models: (1) different levels of errors were added to the features for performance evaluation;(2) a robustness coefficient (Roubust_C) was defined for a quantified and explicit evaluation of the diagnosis robustness. The diagnostic models employing the proposed feature extraction method can not only achieve the higher performance of around 100% but also higher robustness for diagnosis models. Despite the initial performance being similar, the KNN demonstrated a superior robustness after feature selection and re-embedding by triplet-loss method, which suggests the necessity of robustness evaluation for the machine learning models and the effectiveness of the defined robustness coefficient. This work hopes to give new insights to the robust diagnosis of high temperature PEM fuel cells and more comprehensive performance evaluation of the data-driven method for diagnostic application. 展开更多
关键词 PEM fuel cell Data-driven diagnosis Robustness improvement and evaluation Electrochemical impedance spectroscopy
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Debaryomyces hansenii supplementation in low fish meal diets promotes growth,modulates microbiota and enhances intestinal condition in juvenile marine fish
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作者 Ignasi Sanahuja Alberto Ruiz +9 位作者 Joana P.Firmino Felipe E.Reyes-López Juan B.Ortiz-Delgado Eva Vallejos-Vidal Lluis Tort Dariel Tovar-Ramírez Isabel M.Cerezo Miguel A.Moriñigo Carmen Sarasquete Enric Gisbert 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期253-276,共24页
Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a ye... Background The development of a sustainable business model with social acceptance,makes necessary to develop new strategies to guarantee the growth,health,and well-being of farmed animals.Debaryomyces hansenii is a yeast species that can be used as a probiotic in aquaculture due to its capacity to i)promote cell proliferation and differen-tiation,ii)have immunostimulatory effects,iii)modulate gut microbiota,and/or iv)enhance the digestive function.To provide inside into the effects of D.hansenii on juveniles of gilthead seabream(Sparus aurata)condition,we inte-grated the evaluation of the main key performance indicators coupled with the integrative analysis of the intestine condition,through histological and microbiota state,and its transcriptomic profiling.Results After 70 days of a nutritional trial in which a diet with low levels of fishmeal(7%)was supplemented with 1.1%of D.hansenii(17.2×10^(5) CFU),an increase of ca.12%in somatic growth was observed together with an improve-ment in feed conversion in fish fed a yeast-supplemented diet.In terms of intestinal condition,this probiotic modu-lated gut microbiota without affecting the intestine cell organization,whereas an increase in the staining intensity of mucins rich in carboxylated and weakly sulphated glycoconjugates coupled with changes in the affinity for certain lectins were noted in goblet cells.Changes in microbiota were characterized by the reduction in abundance of several groups of Proteobacteria,especially those characterized as opportunistic groups.The microarrays-based transcrip-tomic analysis found 232 differential expressed genes in the anterior-mid intestine of S.aurata,that were mostly related to metabolic,antioxidant,immune,and symbiotic processes.Conclusions Dietary administration of D.hansenii enhanced somatic growth and improved feed efficiency param-eters,results that were coupled to an improvement of intestinal condition as histochemical and transcriptomic tools indicated.This probiotic yeast stimulated host-microbiota interactions without altering the intestinal cell organization nor generating dysbiosis,which demonstrated its safety as a feed additive.At the transcriptomic level,D.hansenii pro-moted metabolic pathways,mainly protein-related,sphingolipid,and thymidylate pathways,in addition to enhance antioxidant-related intestinal mechanisms,and to regulate sentinel immune processes,potentiating the defensive capacity meanwhile maintaining the homeostatic status of the intestine. 展开更多
关键词 Debaryomyces hansenii Intestine condition Low fish meal diet MICROBIOTA TRANSCRIPTOMICS Yeast probiotic
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Development of a multiplex polymerase chain reaction assay for detection of hepatitis C virus,hepatitis B virus,and human immunodeficiency virus 1
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作者 Waleed Abdelgaber Nemr Radwan K Nashwa 《World Journal of Virology》 2024年第1期95-106,共12页
BACKGROUND Hepatitis C virus(HCV),hepatitis B virus(HBV),and human immunodeficiency virus 1(HIV-1)are the most epidemic blood-borne viruses,posing threats to human health and causing economic losses to nations for com... BACKGROUND Hepatitis C virus(HCV),hepatitis B virus(HBV),and human immunodeficiency virus 1(HIV-1)are the most epidemic blood-borne viruses,posing threats to human health and causing economic losses to nations for combating the infection transmission.The diagnostic methodologies that depend on the detection of viral nucleic acids are much more expensive,but they are more accurate than sero-logical testing.AIM To develop a rapid,cost-effective,and accurate diagnostic multiplex polymerase chain reaction(PCR)assay for simultaneous detection of HCV,HBV,and HIV-1.METHODS The design of the proposed PCR assay targets the amplification of a short conserved region featured with a distinguishable melting profile and electro-phoretic molecular weight inside each viral genome.Therefore,this diagnostic method will be appropriate for application in both conventional(combined with electrophoresis)and real-time PCR facilities.Confirmatory in silico investigations were conducted to prove the capability of the approached PCR assay to detect variants of each virus.Then,Egyptian isolates of each virus were subjected to the wet lab examination using the given diagnostic assay.RESULTS The in silico investigations confirmed that the PCR primers can match many viral variants in a multiplex PCR assay.The wet lab experiment proved the efficiency of the assay in distinguishing each viral type through high-resolution melting analysis.Compared to related published assays,the proposed assay in the current study is more sensitive and competitive with many expensive PCR assays.CONCLUSION This study provides a simple,cost-effective,and sensitive diagnostic PCR assay facilitating the detection of the most epidemic blood-borne viruses;this makes the proposed assay promising to be substitutive for the mistakable and cheap serological-based assays. 展开更多
关键词 DIAGNOSIS Blood-borne viruses Multiplex polymerase chain reaction High-resolution melting
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Efficacy and safety of bamlanivimab in patients with COVID-19:A systematic review and meta-analysis
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作者 Behnam Amani Lida Khodavirdilou +3 位作者 Kourosh Rajabkhah Vida Kardan Moghaddam Arash Akbarzadeh Bahman Amani 《World Journal of Virology》 2024年第1期120-132,共13页
BACKGROUND Monoclonal antibodies(mAbs)have shown clinical benefits against coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Several studies have reported the use ... BACKGROUND Monoclonal antibodies(mAbs)have shown clinical benefits against coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Several studies have reported the use of bamlanivimab as a promising treatment option for COVID-19.AIM To synthesize the latest evidence for the efficacy and safety of bamlanivimab alone in the treatment of adult patients with COVID-19.METHODS A literature search was conducted in PubMed,Cochrane Library,Web of Science,medRxiv,and Google Scholar using“SARS-CoV-2”,“COVID-19”,“LY-CoV555”,and“Bamlanivimab”keywords up to January 25,2023.The quality of included studies was assessed using the Cochrane bias tools.The Comprehensive Meta-Analysis software version 3.0 was used to analyze the data.RESULTS A total of 30 studies involving 47368 patients were included.A significant difference was observed between the bamlanivimab and standard of care/placebo groups in terms of mortality rate[risk ratio(RR)=50,95%confidence interval(CI):0.36-0.70],hospitalization rate(RR=0.51;95%CI:0.39-0.68),and emergency department(ED)visits(RR=0.69;95%CI:0.47-0.99);while the two groups exhibited no significant difference in terms of intensive care unit(ICU)admission(P>0.05).Compared to other mAbs,bamlanivimab was associated with a higher rate of hospitalization(RR=1.44;95%CI:1.07-1.94).However,no significant difference was detected between the bamlanivimab and other mAbs groups in terms of mortality rate,ICU admission,and ED(P>0.05).The incidence of any adverse events was similar between the bamlanivimab and control groups(P>0.05).CONCLUSION Although the results suggest the efficacy and safety of bamlanivimab in COVID-19 patients,further research is required to confirm the efficacy of this drug for the current circulating SARS-CoV-2 variants. 展开更多
关键词 SARS-CoV-2 COVID-19 Bamlanivimab Monoclonal antibody META-ANALYSIS
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Milestones of Wireless Communication Networks and Technology Prospect of Next Generation(6G) 被引量:1
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作者 Mohammed H.Alsharif Md.Sanwar Hossain +3 位作者 Abu Jahid Muhammad Asghar Khan Bong Jun Choi Samih M.Mostafa 《Computers, Materials & Continua》 SCIE EI 2022年第6期4803-4818,共16页
Since around 1980,a new generation of wireless technology has arisen approximately every 10 years.First-generation(1G)and secondgeneration(2G)began with voice and eventually introduced more and more data in third-gene... Since around 1980,a new generation of wireless technology has arisen approximately every 10 years.First-generation(1G)and secondgeneration(2G)began with voice and eventually introduced more and more data in third-generation(3G)and became highly popular in the fourthgeneration(4G).To increase the data rate along with low latency and mass connectivity the fifth-generation(5G)networks are being installed from 2020.However,the 5G technology will not be able to fulfill the data demand at the end of this decade.Therefore,it is expected that 6G communication networks will rise,providing better services through the implementation of new enabling technologies and allowing users to connect everywhere.6G technology would not be confined to cellular communications networks,but would also comply with non-terrestrial communication system requirements,such as satellite communication.The ultimate objectives of this work are to address the major challenges of the evolution of cellular communication networks and to discourse the recent growth of the industry based on the key scopes of application and challenges.The main areas of research topics are summarized into(i)major 6G wireless networkmilestones;(ii)key performance indicators;(iii)future new applications;and(iv)potential fields of research,challenges,and open issues. 展开更多
关键词 Wireless networks beyond 5G 6G communications terahertz frequency terahertz communications holographic calls
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An Improved LSTM-PCA Ensemble Classifier for SQL Injection and XSS Attack Detection 被引量:1
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作者 Deris Stiawan Ali Bardadi +7 位作者 Nurul Afifah Lisa Melinda Ahmad Heryanto Tri Wanda Septian Mohd Yazid Idris Imam Much Ibnu Subroto Lukman Rahmat Budiarto 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1759-1774,共16页
The Repository Mahasiswa(RAMA)is a national repository of research reports in the form of final assignments,student projects,theses,dissertations,and research reports of lecturers or researchers that have not yet been... The Repository Mahasiswa(RAMA)is a national repository of research reports in the form of final assignments,student projects,theses,dissertations,and research reports of lecturers or researchers that have not yet been published in journals,conferences,or integrated books from the scientific repository of universities and research institutes in Indonesia.The increasing popularity of the RAMA Repository leads to security issues,including the two most widespread,vulnerable attacks i.e.,Structured Query Language(SQL)injection and cross-site scripting(XSS)attacks.An attacker gaining access to data and performing unauthorized data modifications is extremely dangerous.This paper aims to provide an attack detection system for securing the repository portal from the abovementioned attacks.The proposed system combines a Long Short–Term Memory and Principal Component Analysis(LSTM-PCA)model as a classifier.This model can effectively solve the vanishing gradient problem caused by excessive positive samples.The experiment results show that the proposed system achieves an accuracy of 96.85%using an 80%:20%ratio of training data and testing data.The rationale for this best achievement is that the LSTM’s Forget Gate works very well as the PCA supplies only selected features that are significantly relevant to the attacks’patterns.The Forget Gate in LSTM is responsible for deciding which information should be kept for computing the cell state and which one is not relevant and can be discarded.In addition,the LSTM’s Input Gate assists in finding out crucial information and stores specific relevant data in the memory. 展开更多
关键词 LSTM PCA ensemble classifier SQL injection XSS
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Extracellular vesicles from oviductal and uterine fluids supplementation in sequential in vitro culture improves bovine embryo quality 被引量:1
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作者 Cláudia Lima Verde Leal Karina Canón-Beltrán +9 位作者 Yulia N.Cajas Meriem Hamdi Aracelli Yaryes María Gemma Millán de la Blanca Paula Beltrán-Brena Rosane Mazzarella Juliano Coelho da Silveira Alfonso Gutiérrez-Adán Encina M González Dimitrios Rizos 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期114-133,共20页
Background:In vitro production of bovine embryos is a well-established technology,but the in vitro culture(IVC)system still warrants improvements,especially regarding embryo quality.This study aimed to evaluate the ef... Background:In vitro production of bovine embryos is a well-established technology,but the in vitro culture(IVC)system still warrants improvements,especially regarding embryo quality.This study aimed to evaluate the effect of extracellular vesicles(EVs)isolated from oviductal(OF)and uterine fluid(UF)in sequential IVC on the development and quality of bovine embryos.Zygotes were cultured in SOF supplemented with either BSA or EVs-depleted fetal calf serum(dFCS)in the presence(BSA-EV and dFCS-EV)or absence of EVs from OF(D1 to D4)and UF(D5 to D8),mimicking in vivo conditions.EVs from oviducts(early luteal phase)and uterine horns(mid-luteal phase)from slaughtered heifers were isolated by size exclusion chromatography.Blastocyst rate was recorded on days 7-8 and their quality was assessed based on lipid contents,mitochondrial activity and total cell numbers,as well as survival rate after vitrification.Relative mRNA abundance for lipid metabolism-related transcripts and levels of phosphorylated hormonesensitive lipase(pHSL)proteins were also determined.Additionally,the expression levels of 383 miRNA in OF-and UF-EVs were assessed by qRT-PCR.Results:Blastocyst yield was lower(P<0.05)in BSA treatments compared with dFCS treatments.Survival rates after vitrification/warming were improved in dFCS-EVs(P<0.05).EVs increased(P<0.05)blastocysts total cell number in dFCS-EV and BSA-EV compared with respective controls(dFCS and BSA),while lipid content was decreased in dFCSEV(P<0.05)and mitochondrial activity did not change(P>0.05).Lipid metabolism transcripts were affected by EVs and showed interaction with type of protein source in medium(PPARGC1B,LDLR,CD36,FASN and PNPLA2,P<0.05).Levels of pHSL were lower in dFCS(P<0.05).Twenty miRNA were differentially expressed between OF-and UF-EVs and only bta-miR-148b was increased in OF-EVs(P<0.05).Conclusions:Mimicking physiological conditions using EVs from OF and UF in sequential IVC does not affect embryo development but improves blastocyst quality regarding survival rate after vitrification/warming,total cell number,lipid content,and relative changes in expression of lipid metabolism transcripts and lipase activation.Finally,EVs miRNA contents may contribute to the observed effects. 展开更多
关键词 CATTLE CRYOPRESERVATION Embryo development EXOSOMES Lipid metabolism miRNAs OVIDUCT UTERUS
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Agreements’profile of Scheimpflug-based optical biometer with gold standard partial coherence interferometry 被引量:1
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作者 Sara Sardari Akbar Fotouhi +1 位作者 Ebrahim Jafarzadehpur Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期2095-2104,共10页
AIM:To determine the agreement of ocular biometric indices including axial length,keratometric readings,anterior chamber depth,and horizontal corneal diameter between the Pentacam AXL and IOL Master 500.METHODS:The st... AIM:To determine the agreement of ocular biometric indices including axial length,keratometric readings,anterior chamber depth,and horizontal corneal diameter between the Pentacam AXL and IOL Master 500.METHODS:The study was a large cross-sectional population-based study(Tehran Geriatric Eye Study)conducted from Jan 2019 to Jan 2020.A total of 160 clusters were randomly selected proportional to size(each cluster contained 20 individuals)from 22 strata of Tehran city.All people aged 60y and above were invited to participate in the study.For all participants,preliminary ocular examinations were performed including the measurement of uncorrected and best-corrected visual acuity,objective and subjective refraction,anterior and posterior segment examinations.All participants underwent an ocular biometry using the Pentacam AXL and IOL Master 500.RESULTS:The 95%limits of agreement(LoA)between the two devices were-0.13 to 0.19,-0.15 to 0.17,and-0.13 to 0.19 in normal,pseudophakic,and cataractous eyes,respectively.With increasing the axial length,the difference between the two devices significantly increased in all three groups of normal,pseudophakic,and cataractous eyes(P<0.001).The 95% LoAs between the two devices regarding the mean keratometry shows that the best LoAs were seen in cataractous(-0.33 to 0.81)and followed by normal eyes(-0.36 to 0.86)and the pseudophakic eyes(-0.48 to 0.90)had the widest LoA.The 95% LoAs for horizontal corneal diameter measurements were-0.08 to 0.86,-0.03 to 0.83,and-0.07 to 0.87 in normal,pseudophakic,and cataractous eyes,respectively.The 95% LoAs of anterior chamber depth measurements between the two devices was-0.39 to 0.19 and-0.37 to 0.13 in normal eyes and cataractous,respectively.CONCLUSION:The Pentacam AXL has excellent agreement with the gold standard,IOL Master 500 in measuring axial length.In eyes with cataracts,the difference between the two devices is more scattered.With the increasing of axial length,the difference between the two devices increased,which should be considered when using Pentacam AXL. 展开更多
关键词 ocular biometry optical biometer Pentacam AXL
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Encapsulation of ionic liquid, phosphotungstic acid inside the nanocages of MIL-101(Cr): Effective and reusable catalyst for efficient solvent-free oxidative desulfurization from fuel oil
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作者 Bo-Long Jiang Dong-Xu Zhang +3 位作者 Dan-Dan Yuan Yan-Guang Chen Tian-Zhen Hao Hua Song 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3865-3874,共10页
Oxidative desulfurization from fuel oil is one of the important methods for deep desulfurization.The development of efficient oxidative desulfurization catalysts is crucial for improving the desulfurization performanc... Oxidative desulfurization from fuel oil is one of the important methods for deep desulfurization.The development of efficient oxidative desulfurization catalysts is crucial for improving the desulfurization performance.Successful encapsulation of phosphotungstic acid(HPW)and ionic liquid(BMImBr)inside the mesoporous cages of MIL-101(Cr)was accomplished through a combination of“bottle around ship”and“ship in bottle”methods.The obtained BMImPW@MIL-101(Cr)composite was characterized by XRD,FTIR,BET,SEM,XPS and ICP methods.Results indicated that the BMImPW@MIL-101(Cr)composites with PW^(3−) loading of 23.1–50.7 wt%were obtained,demonstrating that the“bottle around ship”method is beneficial to make full use of nanocages of MIL-101(Cr)to obtain expected high loading of active PW^(3−) .The BMImPW@MIL-101(Cr)exhibits excellent reusability with no evidence of leaching of active PW^(3−) and BMIm^(+),and well-preserved structure after successive cycles of regeneration and reuse.The significantly improved stability of BMImPW@MIL-101(Cr)as compared to HPW@MIL-101(Cr)is possibly because the leaching of the active PW^(3−) −sites can be greatly suppressed by forming large size of BMImPW owing to introduction of BMIm^(+)cation.The BMImPW@MIL-101(Cr)exhibited excellent catalytic activity for solvent free oxidative desulfurization of refractory sulfides.The enhanced oxidative desulfurization activity as compared to HPW@MIL-101(Cr)can be explained by the intimate contact of sulfides with active PW^(3−) sites owing the strong attraction of BMIm^(+)cation with the sulfides. 展开更多
关键词 Metal organic frameworks Phosphotungstic acid lonic liquids Stability Oxidative desulfurization
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Fungal diversity and community composition responses to the reintroduction of fire in a non-managed Mediterranean shrubland ecosystem
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作者 Juncal Espinosa Tatek Dejene +3 位作者 Mercedes Guijarro Xim Cerdá Javier Madrigal Pablo Martín-Pinto 《Forest Ecosystems》 SCIE CSCD 2023年第2期268-278,共11页
Background:More than a decade of fire suppression has changed the structure of fire-adapted shrubland ecosystems in Spain’s National Parks,which are now at extreme risk of uncontrolled wildfires.Prescribed burning ca... Background:More than a decade of fire suppression has changed the structure of fire-adapted shrubland ecosystems in Spain’s National Parks,which are now at extreme risk of uncontrolled wildfires.Prescribed burning can mitigate the risk of wildfires by reducing the fuel load but prescribed burning may also alter the soil properties and reduce microbial and fungal activity,causing changes in the availability of nutrients deep in the soil layer.Although fungal communities are a vital part of post-fire restoration,some fire effects remain unclear.To examine the short-term effects of prescribed burning on soil fungal communities in Doñana Biological Reserve(SW Spain),we collected soil samples pre-burn and 1 day,6 and 12 months post-burn from burned plots to perform physicochemical and metabarcode DNA analyses.Results:Prescribed burning had no significant effect on the total fungal operational taxonomic unit richness and abundance.However,changes in soil pH,nitrogen and potassium content post-burn affected fungal community composition.Small non-significant changes in pH and phosphorous affected the composition of ectomycorrhizal fungi.Conclusions:The ectomycorrhizal fungal community appears to be resilient to the effects of low-to moderate-intensity fires and saprotrophic taxa may benefit from this kind of fire.This finding revealed that prescribed burning is a potentially valuable management tool for reducing fire hazards in shrublands that has little effect on the total richness and abundance of fungal communities. 展开更多
关键词 Doñana National Park Ectomycorrhizal fungi Fire ecology Forest management Global change Prescribed burning WILDFIRE Saprotrophic fungi
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Enhanced oxidation and overheating resistance of the extruded Mg–Zn–Al–Mn magnesium alloy by Calcium addition
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作者 Hanieh Yeganeh Ahmad Bahmani +4 位作者 Mehrab Lotfpour Mehdi Malekan Masoud Emamy Behzad Nayebi Kwang Seon Shin 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第4期1276-1291,共16页
The effects of Ca addition on the microstructure and oxidation properties of a new Mg alloy were studied.The oxidation behavior of the alloys was analyzed by thermal analysis and material characterization of the alloy... The effects of Ca addition on the microstructure and oxidation properties of a new Mg alloy were studied.The oxidation behavior of the alloys was analyzed by thermal analysis and material characterization of the alloys exposed in flame environment;and both electrical and induction furnaces.Moreover,the surface layers were characterized using field emission scanning electron microscopy,and X-ray diffraction technique.It was found that increasing the Ca addition reduces the grain size and increases the fraction of the secondary phases,and enhances the mechanical properties.Moreover,increasing the Ca contents resulted in the formation of a dense CaO/MgO layer on the surface prohibited the oxygen diffusion and assisted in protection of the substrate against further oxidation.Therefore,ignition temperature was increased from 680℃ to 890℃ after addition of the Ca element.The mechanical properties and ignition behavior of the current materials was compared with the literature which it showed an excellent combination of the properties in the developed alloys. 展开更多
关键词 Mg alloys Oxidation properties Ca addition Microstructure Intermetallic phases
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Formation of precipitates and recrystallization resistance in Al-Sc-Zr alloys 被引量:10
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作者 贾志宏 Jostein RφYSET +1 位作者 Jan Ketil SOLBERG 刘庆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期1866-1871,共6页
Al-x%Sc-0.11%Zr alloys (x=0, 0.02, 0.05, 0.08, 0.11, 0.15) were produced by a chill cast procedure. The effect of Sc content on the precipitation of Al3(Sc,Zr) during heat treatment at 475 °C for 12 h was stu... Al-x%Sc-0.11%Zr alloys (x=0, 0.02, 0.05, 0.08, 0.11, 0.15) were produced by a chill cast procedure. The effect of Sc content on the precipitation of Al3(Sc,Zr) during heat treatment at 475 °C for 12 h was studied. Nucleation, precipitation and distribution of Al3(Sc,Zr) precipitates were found to be strongly related to the Sc content. With increasing the Sc content, the average radius of the precipitates decreases, while the number density of the precipitates increases, as investigated by transmission electron microscopy (TEM). The distribution of the precipitates becomes more and more homogeneous when the Sc content is increased. The recrystallization resistance of samples that was 90% cold rolled and isothermal annealed for half an hour in the temperature range of 200-600 °C was investigated. The results show that the recrystallization temperature varies from 250 °C for the alloy without Sc to about 600 °C for the alloy containing 0.15% Sc because of the high density of Al3(Sc,Zr) precipitates. 展开更多
关键词 aluminium alloy PRECIPITATE recrystallization resistance
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Precipitation behaviour of Al_3Zr precipitate in Al-Cu-Zr and Al-Cu-Zr-Ti-V alloys 被引量:9
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作者 贾志宏 Jean-Philippe COUZINIé +6 位作者 Nadia CHERDOUDI Ivan GUILLOT LarsRNBERG Petter SHOLT Stig BRUSETHAUG Bruno BARLAS5 Denis MASSINON 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第8期1860-1865,共6页
The precipitation behaviours of Al3Zr precipitate in the Al-Cu-Zr and Al-Cu-Zr-Ti-V alloys were studied by transmission electron microscopy. Metastable Al3Zr precipitates are homogeneously nucleated in dendrite centre... The precipitation behaviours of Al3Zr precipitate in the Al-Cu-Zr and Al-Cu-Zr-Ti-V alloys were studied by transmission electron microscopy. Metastable Al3Zr precipitates are homogeneously nucleated in dendrite centres resulting in homogeneous distribution. However, the precipitation in the interdendritic regions is complex and the precipitation morphologies, helical-like and stripe-like shapes, were observed, which are composed of many spherical Al3Zr precipitates. The stripe-like precipitate clusters have preferential orientations along with the -100- Al directions, which is inferred to be related to θ′(Al2Cu) and θ phases. Addition of Cu can accelerate the L12→D023 structural transformation of the Al3Zr precipitate. 展开更多
关键词 aluminium alloys Al3Zr precipitate phase transformation
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Flavone improves liver damage in nicotine-exposed rats via the Nrf2/HO-1 pathway
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作者 Nora A.Elsayed Fatma SM Moawed +2 位作者 Esraa SA Ahmed Ahmed Hammad Omayma AR Abo-Zaid 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第8期341-349,共9页
Objective:To assess the hepatoprotective effects of flavone on nicotine-induced liver damage.Methods:Thirty-six rats were allocated into six groups:the control group,the nicotine group,the flavone alone groups(10 and ... Objective:To assess the hepatoprotective effects of flavone on nicotine-induced liver damage.Methods:Thirty-six rats were allocated into six groups:the control group,the nicotine group,the flavone alone groups(10 and 25 mg/kg/body weight),and the nicotine groups treated with flavone(10 and 25 mg/kg/body weight).Liver function,oxidative stress,Nrf2 pathway(HO-1,Nrf2,and Keap-1),and inflammatory markers(IL-17,TNF-α,and NF-κB)were evaluated.Additionally,a histopathological examination of liver tissues was performed.Results:Nicotine increased liver damage,inflammation,and oxidative stress.However,flavone suppressed nicotine-induced liver enzymes,oxidative stress,and inflammation,as manifested by increased antioxidants and decreased malondialdehyde level,liver enzymatic activities,and inflammatory markers.Flavone(10 and 25 mg/kg/body weight)also reduced the level of Keap-1 and increased HO-1 and Nrf2 levels in the liver of nicotine-exposed rats.Conclusions:Flavone has hepatoprotective properties and may slow the progression of liver injury by reducing oxidative stress,liver enzymes,and inflammation possibly via the Nrf2 pathway. 展开更多
关键词 FLAVONE NICOTINE Liver NRF2 HO-1 NF-κB
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Alpha7 nicotinic receptors as potential theranostic targets for experimental stroke
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作者 Maider Garbizu Laura Aguado Abraham Martín 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期939-940,共2页
Inflammatory reflex and cholinergic anti-inflammatory pathway:Innate immune system triggers a local inflammatory response following an injury or a pathogen invasion.Likewise,this inflammatory response is limited by ra... Inflammatory reflex and cholinergic anti-inflammatory pathway:Innate immune system triggers a local inflammatory response following an injury or a pathogen invasion.Likewise,this inflammatory response is limited by rapid,localized,and adaptive anti-inflammatory responses which are crucial for maintaining homeostasis.Hence,the loss of these responses converts a limited and protective inflammatory response into an excessive and harmful response.Anti-inflammatory responses are integrated into the central nervous system,since the central nervous system accumulates information about harmful events,activates defenses,and builds memory for survival.At the same time,it has been demonstrated that hypothalamic neuronal signaling can be altered by inflammation in peripheral tissues.Additionally,immune cells release neuropeptides and neurotransmitters such as acetylcholine(ACh),the main neurotransmitter of the parasympathetic autonomic nervous system,evidencing the communication between the immune and nervous systems(Tracey,2002). 展开更多
关键词 protective INVASION ALPHA
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Recent Progress of the Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) Mission
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作者 WANG Chi ESCOUBET Philippe +2 位作者 FORSYTH Colin LI Jing AGNOLON David 《空间科学学报》 CAS CSCD 北大核心 2024年第4期692-698,共7页
The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction ... The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction of the solar wind with the Earth’s magnetosphere in a global manner.As of May 2024,the SMILE mission is in phase-D with an expected launch date of September 2025.This report summarizes developments in the mission during the past two years. 展开更多
关键词 SMILE Soft X-ray Imager Ultra-Violet Imager Light Ion Analyzer MAGNETOMETER
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增材制造Ti6Al4V合金的闪速等离子体电解氧化与在生理介质中的电化学行为
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作者 H.MORA-SANCHEZ C.RAMOS +3 位作者 M.MOHEDANO B.TORRES R.ARRABAL E.MATYKINA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第4期1150-1166,共17页
研究激光粉末床熔融增材制造(AM)(又称直接金属激光烧结)技术制备的Ti6Al4V合金等离子体电解氧化(PEO)处理及其电化学行为。通过短时间(<120 s)PEO处理(也称闪速PEO),在AM合金和传统合金表面制备了3~10μm厚、含Ca和P的涂层。然后在... 研究激光粉末床熔融增材制造(AM)(又称直接金属激光烧结)技术制备的Ti6Al4V合金等离子体电解氧化(PEO)处理及其电化学行为。通过短时间(<120 s)PEO处理(也称闪速PEO),在AM合金和传统合金表面制备了3~10μm厚、含Ca和P的涂层。然后在改良的α-MEM溶液中,通过动电位极化曲线和电化学阻抗谱(EIS)评估了合金的电化学行为。与传统合金相比,AM合金中形成了细小的层片状α显微组织和层间小尺寸的β相颗粒,这促使了火花的产生,从而促进了PEO涂层的生长。闪速PEO涂层提高了传统合金和AM合金的耐腐蚀性,最薄的涂层(<3μm)提供了高达3倍的保护。AM Ti6Al4V由于其高的晶界密度,易受局部缝隙腐蚀的影响。而即使短至35 s的闪速PEO处理也足以成功避免这种情况。 展开更多
关键词 增材制造 激光粉末床熔融 等离子体电解氧化 闪速PEO 缝隙腐蚀 α-MEM
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