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Spatial niche segregation between bird species in the Białowieża primeval forest(NE Poland)
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作者 Oliwia Karpińska Katarzyna Kamionka-Kanclerska +2 位作者 Patryk Czortek Marcin K.Dyderski Dorota Czeszczewik 《Forest Ecosystems》 SCIE CSCD 2023年第4期483-493,共11页
Drivers of bird niche separation in temperate primeval forests have not yet been determined,due to the low number of intact forest sites.Here,we analyzed the general patterns of niche usage on trees by birds’assembla... Drivers of bird niche separation in temperate primeval forests have not yet been determined,due to the low number of intact forest sites.Here,we analyzed the general patterns of niche usage on trees by birds’assemblages.We tested how tree species affect the sharing of space in an assemblage of birds and their level of specialization.We conducted our study in the Białowieża primeval forest(NE Poland).During two breeding seasons,we observed bird positions on trees,divided into three vertical and six horizontal zones in 768 observation points.Based on the interaction networks framework we calculated the Kullback-Leibler distance d′as a metric of species specialization and the resource range RR index,which estimates the species’specificity based on the fraction of space utilized with a non-zero performance.The d′index was the highest in the lower understory for all parts of the tree on the basis of the position from the trunk.The RR index was the highest in the lower understory for all parts based on the position from the trunk.Regarding the tree species,the lowest d′index was observed in all tree species together,and hornbeam,whereas the highest in oak.At the tree species level,the RR index was the lowest for hornbeam.We show tree species importance in forest space sharing in the case of bird assemblages.Hornbeam,alder,and spruce are universal species that were used by birds almost entirely.In contrast,oak,lime,and maple were only partially used.Tree species with less complex structures could shape bird assemblages,as they could offer birds much fewer niches to realize.Therefore,we showed that high specialization and niche separation are drivers of high bird diversity.Consequently maintaining a diverse stand structure is crucial for biodiversity conservation. 展开更多
关键词 Tree use Niche partitioning Foraging guild SPECIALIZATION Habitat filtering Foundation species Tree species effect
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Deep Learning-Based ECG Classification for Arterial Fibrillation Detection
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作者 Muhammad Sohail Irshad Tehreem Masood +3 位作者 Arfan Jaffar Muhammad Rashid Sheeraz Akram Abeer Aljohani 《Computers, Materials & Continua》 SCIE EI 2024年第6期4805-4824,共20页
The application of deep learning techniques in the medical field,specifically for Atrial Fibrillation(AFib)detection through Electrocardiogram(ECG)signals,has witnessed significant interest.Accurate and timely diagnos... The application of deep learning techniques in the medical field,specifically for Atrial Fibrillation(AFib)detection through Electrocardiogram(ECG)signals,has witnessed significant interest.Accurate and timely diagnosis increases the patient’s chances of recovery.However,issues like overfitting and inconsistent accuracy across datasets remain challenges.In a quest to address these challenges,a study presents two prominent deep learning architectures,ResNet-50 and DenseNet-121,to evaluate their effectiveness in AFib detection.The aim was to create a robust detection mechanism that consistently performs well.Metrics such as loss,accuracy,precision,sensitivity,and Area Under the Curve(AUC)were utilized for evaluation.The findings revealed that ResNet-50 surpassed DenseNet-121 in all evaluated categories.It demonstrated lower loss rate 0.0315 and 0.0305 superior accuracy of 98.77%and 98.88%,precision of 98.78%and 98.89%and sensitivity of 98.76%and 98.86%for training and validation,hinting at its advanced capability for AFib detection.These insights offer a substantial contribution to the existing literature on deep learning applications for AFib detection from ECG signals.The comparative performance data assists future researchers in selecting suitable deep-learning architectures for AFib detection.Moreover,the outcomes of this study are anticipated to stimulate the development of more advanced and efficient ECG-based AFib detection methodologies,for more accurate and early detection of AFib,thereby fostering improved patient care and outcomes. 展开更多
关键词 Convolution neural network atrial fibrillation area under curve ECG false positive rate deep learning CLASSIFICATION
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Decade of optimizing therapy with direct-acting antiviral drugs and the changing profile of patients with chronic hepatitis C 被引量:1
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作者 MichałBrzdęk Dorota Zarębska-Michaluk +3 位作者 Federica Invernizzi Marta Cilla Krystyna Dobrowolska Robert Flisiak 《World Journal of Gastroenterology》 SCIE CAS 2023年第6期949-966,共18页
Chronic infection with the hepatitis C virus(HCV)remains a major health problem affecting approximately 58 million people worldwide.In the era of interferon(IFN)-based regimens,patients particularly infected with geno... Chronic infection with the hepatitis C virus(HCV)remains a major health problem affecting approximately 58 million people worldwide.In the era of interferon(IFN)-based regimens,patients particularly infected with genotypes 1 and 4 achieved a low response rate.The implementation of direct-acting antivirals changed the landscape of HCV treatment.The increase in effectiveness provided us with the hope of eliminating HCV as a significant public threat by 2030.In the following years,there was an observed improvement in the treatment of HCV with genotype-specific regimens and highly effective pangenotypic options that are the most recent stage of the revolution.The optimization of therapy was accompanied by changes in the patient profile from the beginning of the IFN-free era over time.Patients treated with antiviral therapies were younger in successive periods,less burdened with comorbidities and comedications,more frequently treatment-naïve and had less advanced liver disease.Before the IFN-free era,specific subpopulations such as patients with HCV/HIV coinfection,those with a history of previous treatment,patients with renal impairment or with cirrhosis had lower chances for a virologic response.Currently,these populations should no longer be considered difficult to treat.Despite the high effectiveness of HCV therapy,there is a small percentage of patients with treatment failure.However,they can be effectively retreated with pangenotypic rescue regimens. 展开更多
关键词 Hepatitis C virus INTERFERON Direct-acting antiviral EPIDEMIOLOGY Chronic hepatitis C
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Investigation of the sodium storage mechanism of iron fluoride hydrate cathodes using X-ray absorption spectroscopy and mossbauer spectroscopy
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作者 Ghulam Ali Muhammad Akbar +4 位作者 Faiza Jan Iftikhar Qamar Wali Beata Kalska Szostko Dariusz Satuła Kyung Yoon Chung 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期535-542,I0014,共9页
Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_... Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_(3)·0.5H_(2)O)electrode for sodium-ion batteries(SIBs).The electrode material is prepared by employing an ionic liquid 1-butyl-3-methylimidazolium-tetrafluoroborate,which serves as a reaction medium and precursor for F^(-)ions.The crystal structure of FeF_(3)·0.5H_(2)O is observed as pyrochlore type with large open 3-D tunnels and a unit cell volume of 1129A^(3).The morphology of FeF_(3)·0.5H_(2)O is spherical shape with a mesoporous structure.The microstructure analysis reveals primary particle size of around 10 nm.The FeF_(3)·0.5H_(2)O cathode exhibits stable discharge capacities of 158,210,and 284 mA h g^(-1) in three different potential ranges of 1.5-4.5,1.2-4.5,and 1.0-4.5 V,respectively at 0.05 C rate.The specific capacities remained stable in over 50 cycles in all three potential ranges,while the rate capability was best in the potential range of 1.5-4.5 V.The electrochemical sodium storage mechanism is studied using X-ray absorption spectroscopy,indicating higher conversion at a more discharged state.Ex-situ M?ssbauer spectroscopy strengthens the results for reversible reduction/oxidation of Fe.These results will be favorable to establish high-performance cathode materials with selective voltage window for SIBs. 展开更多
关键词 Iron fluoride Sodium-ion batteries PYROCHLORE X-ray absorption spectroscopy Mössbauer spectroscopy
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A Nonstandard Computational Investigation of SEIR Model with Fuzzy Transmission, Recovery and Death Rates
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作者 Ahmed H.Msmali Fazal Dayan +3 位作者 Muhammad Rafiq Nauman Ahmed Abdullah Ali H.Ahmadini Hassan A.Hamali 《Computers, Materials & Continua》 SCIE EI 2023年第11期2251-2269,共19页
In this article,a Susceptible-Exposed-Infectious-Recovered(SEIR)epidemic model is considered.The equilibrium analysis and reproduction number are studied.The conventional models have made assumptions of homogeneity in... In this article,a Susceptible-Exposed-Infectious-Recovered(SEIR)epidemic model is considered.The equilibrium analysis and reproduction number are studied.The conventional models have made assumptions of homogeneity in disease transmission that contradict the actual reality.However,it is crucial to consider the heterogeneity of the transmission rate when modeling disease dynamics.Describing the heterogeneity of disease transmission mathematically can be achieved by incorporating fuzzy theory.A numerical scheme nonstandard,finite difference(NSFD)approach is developed for the studied model and the results of numerical simulations are presented.Simulations of the constructed scheme are presented.The positivity,convergence and consistency of the developed technique are investigated using mathematical induction,Jacobean matrix and Taylor series expansions respectively.The suggested scheme preserves all these essential characteristics of the disease dynamical models.The numerical and simulation results reveal that the proposed NSFD method provides an adequate representation of the dynamics of the disease.Moreover,the obtained method generates plausible predictions that can be used by regulators to support the decision-making process to design and develop control strategies.Effects of the natural immunity on the infected class are studied which reveals that an increase in natural immunity can decrease the infection and vice versa. 展开更多
关键词 Epidemic model fuzzy parameters NSFD scheme CONVERGENCE POSITIVITY CONSISTENCY
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Climate Change, Who Is Responsible?
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作者 Salifu Abdallah Awasina Robert Akayim +1 位作者 Evans Ntim Amedor John Yao Afetsu 《Open Journal of Applied Sciences》 2023年第12期2431-2446,共16页
The study was carried out to create awareness of the destruction we can cause to ourselves as human beings, if we continue to contribute, by our actions to the natural causes of climate change. The problem is the visi... The study was carried out to create awareness of the destruction we can cause to ourselves as human beings, if we continue to contribute, by our actions to the natural causes of climate change. The problem is the visible destructions all over the world due to climate change;especially when the focus is on the areas of heavy pollutions, the changes in rain pattern, making farmers vulnerable. Increase in temperatures also lead to global warming. The type of research used is descriptive and that deals with qualitative approaches. Data collection involved both primary and secondary sources. The natural causes of climate change include volcanic activity, solar output, Forest Fires, Permafrost, Sunspots, Water Vapor, Man’s Best Friend. Those caused by human are burning of fossil fuels and the conversion of land from forestry to irresponsible agricultural practices. Gases emission from landfills;overpopulation;irresponsible mining;misapplication of fertilizers and other agrochemicals;meat consumption. Evidence of climate change includes change in rainfall pattern, increase in temperatures, extreme drought, change in harmattan pattern. Low production of fruits by trees in the wild;eroded arable lands;annual drying of dams that never dried in decades and also the shortening of lifespan of living things. Effects of climate change include desertification of the world’s arable land, persistent droughts, locally and abroad, unprecedented damage to infrastructure due to acid rain, volcanic eruption, earth quake, coastal erosion, unpredictable farming seasons, extinction threat on the wildlife, marine life extinction, flooding of coastal cities and island nations. Human being is a facilitator of the naturally occurring climate change. Those who mine natural resource without recourse to the laws of the land they occupy, should be dealt with legally. 展开更多
关键词 CLIMATE Natural Manmade VOLCANIC POLLUTION AGRICULTURE
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Optical Ciphering Scheme for Cancellable Speaker Identification System
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作者 Walid El-Shafai Marwa A.Elsayed +5 位作者 Mohsen A.Rashwan Moawad I.Dessouky Adel S.El-Fishawy Naglaa F.Soliman Amel A.Alhussan Fathi EAbd El-Samie 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期563-578,共16页
Most current security and authentication systems are based on personal biometrics.The security problem is a major issue in the field of biometric systems.This is due to the use in databases of the original biometrics.... Most current security and authentication systems are based on personal biometrics.The security problem is a major issue in the field of biometric systems.This is due to the use in databases of the original biometrics.Then biometrics will forever be lost if these databases are attacked.Protecting privacy is the most important goal of cancelable biometrics.In order to protect privacy,therefore,cancelable biometrics should be non-invertible in such a way that no information can be inverted from the cancelable biometric templates stored in personal identification/verification databases.One methodology to achieve non-invertibility is the employment of non-invertible transforms.This work suggests an encryption process for cancellable speaker identification using a hybrid encryption system.This system includes the 3D Jigsaw transforms and Fractional Fourier Transform(FrFT).The proposed scheme is compared with the optical Double Random Phase Encoding(DRPE)encryption process.The evaluation of simulation results of cancellable biometrics shows that the algorithm proposed is secure,authoritative,and feasible.The encryption and cancelability effects are good and reveal good performance.Also,it introduces recommended security and robustness levels for its utilization for achieving efficient cancellable biometrics systems. 展开更多
关键词 Cancellable biometrics jigsaw transform FrFT DRPE speaker identification
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Hand Gesture Recognition for Disabled People Using Bayesian Optimization with Transfer Learning
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作者 Fadwa Alrowais Radwa Marzouk +1 位作者 Fahd N.Al-Wesabi Anwer Mustafa Hilal 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3325-3342,共18页
Sign language recognition can be treated as one of the efficient solu-tions for disabled people to communicate with others.It helps them to convey the required data by the use of sign language with no issues.The lates... Sign language recognition can be treated as one of the efficient solu-tions for disabled people to communicate with others.It helps them to convey the required data by the use of sign language with no issues.The latest develop-ments in computer vision and image processing techniques can be accurately uti-lized for the sign recognition process by disabled people.American Sign Language(ASL)detection was challenging because of the enhancing intraclass similarity and higher complexity.This article develops a new Bayesian Optimiza-tion with Deep Learning-Driven Hand Gesture Recognition Based Sign Language Communication(BODL-HGRSLC)for Disabled People.The BODL-HGRSLC technique aims to recognize the hand gestures for disabled people’s communica-tion.The presented BODL-HGRSLC technique integrates the concepts of compu-ter vision(CV)and DL models.In the presented BODL-HGRSLC technique,a deep convolutional neural network-based residual network(ResNet)model is applied for feature extraction.Besides,the presented BODL-HGRSLC model uses Bayesian optimization for the hyperparameter tuning process.At last,a bidir-ectional gated recurrent unit(BiGRU)model is exploited for the HGR procedure.A wide range of experiments was conducted to demonstrate the enhanced perfor-mance of the presented BODL-HGRSLC model.The comprehensive comparison study reported the improvements of the BODL-HGRSLC model over other DL models with maximum accuracy of 99.75%. 展开更多
关键词 Deep learning hand gesture recognition disabled people computer vision bayesian optimization
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Changes in characteristics of patients with hepatitis C virus-related cirrhosis from the beginning of the interferon-free era
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作者 Michał Brzdęk Dorota Zarębska-Michaluk +13 位作者 Piotr Rzymski Beata Lorenc Adam Kazek Magdalena Tudrujek-Zdunek Justyna Janocha-Litwin Włodzimierz Mazur Dorota Dybowska Hanna Berak Anna Parfieniuk-Kowerda Jakub Klapaczyński Marek Sitko Barbara Sobala-Szczygieł Anna Piekarska Robert Flisiak 《World Journal of Gastroenterology》 SCIE CAS 2023年第13期2015-2033,共19页
BACKGROUND Nearly 290000 patients with chronic hepatitis C die annually from the most severe complications of the disease.One of them is liver cirrhosis,which occurs in about 20%of patients chronically infected with t... BACKGROUND Nearly 290000 patients with chronic hepatitis C die annually from the most severe complications of the disease.One of them is liver cirrhosis,which occurs in about 20%of patients chronically infected with the hepatitis C virus(HCV).Direct-acting antivirals(DAAs),which replaced interferon(IFN)-based regimens,significantly improved the prognosis of this group of patients,increasing HCV eradication rates and tolerability of therapy.Our study is the first to assess changes in patient profile,effectiveness,and safety in the HCV-infected cirrhotic population in the IFN-free era.AIM To document changes in patient characteristics and treatment regimens along with their effectiveness and safety profile over the years.METHODS The studied patients were selected from 14801 chronically HCV-infected individuals who started IFN-free therapy between July 2015 and December 2021 in 22 Polish hepatology centers.The retrospective analysis was conducted in real-world clinical practice based on the EpiTer-2 multicenter database.The measure of treatment effectiveness was the percentage of sustained virologic response(SVR)calculated after excluding patients lost to follow-up.Safety data collected during therapy and the 12-wk post-treatment period included information on adverse events,including serious ones,deaths,and treatment course.RESULTS The studied population(n=3577)was balanced in terms of gender in 2015-2017,while the following years showed the dominance of men.The decline in the median age from 63 in 2015-2016 to 61 years in 2021 was accompanied by a decrease in the percentage of patients with comorbidities and comedications.Treatment-experienced patients dominated in 2015-2016,while treatment-naive individuals gained an advantage in 2017 and reached 93.2%in 2021.Genotype(GT)-specific options were more prevalent in treatment in 2015-2018 and were supplanted by pangenotypic combinations in subsequent years.The effectiveness of the therapy was comparable regardless of the period analyzed,and patients achieved an overall response rate of 95%,with an SVR range of 72.9%-100%for the different therapeutic regimens.Male gender,GT3 infection,and prior treatment failure were identified as independent negative predictors of therapeutic success.CONCLUSION We have documented changes in the profile of HCV-infected cirrhotic patients over the years of accessibility to changing DAA regimens,confirming the high effectiveness of IFN-free therapy in all analyzed periods. 展开更多
关键词 Hepatitis C Liver cirrhosis Direct-acting antivirals Pangenotypic Genotype-specific EPIDEMIOLOGY
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Real-world effectiveness and safety of direct-acting antivirals in hepatitis C virus patients with mental disorders
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作者 Dorota Dybowska Dorota Zarebska-Michaluk +15 位作者 Piotr Rzymski Hanna Berak Beata Lorenc Marek Sitko Michal Dybowski Wlodzimierz Mazur Magdalena Tudrujek-Zdunek Justyna Janocha-Litwin Ewa Janczewska Jakub Klapaczynski Anna Parfieniuk-Kowerda Anna Piekarska Barbara Sobala-Szczygiel Krystyna Dobrowolska Malgorzata Pawlowska Robert Flisiak 《World Journal of Gastroenterology》 SCIE CAS 2023年第25期4085-4098,共14页
BACKGROUND It is estimated that 58 million people worldwide are infected with the hepatitis C virus(HCV).Patients with severe psychiatric disorders could not be treated with previously available interferon-based thera... BACKGROUND It is estimated that 58 million people worldwide are infected with the hepatitis C virus(HCV).Patients with severe psychiatric disorders could not be treated with previously available interferon-based therapies due to their unfavorable side effect profile.This has changed with the introduction of direct-acting antivirals(DAA),although their real-life tolerance and effectiveness in patients with different psychiatric disorders remain to be demonstrated.AIM To evaluate the effectiveness and safety of DAA in patients with various mental illnesses.METHODS This was a retrospective observational study encompassing 14272 patients treated with DAA for chronic hepatitis C in 22 Polish hepatology centers,including 942 individuals diagnosed with a mental disorder(anxiety disorder,bipolar affective disorder,depression,anxiety-depressive disorder,personality disorder,schizophrenia,sleep disorder,substance abuse disorder,and mental illness without a specific diagnosis).The safety and effectiveness of DAA in this group were compared to those in a group without psychiatric illness(n=13330).Antiviral therapy was considered successful if serum ribonucleic acid(RNA)of HCV was undetectable 12 wk after its completion[sustained virologic response(SVR)].Safety data,including the incidence of adverse events(AEs),serious AEs(SAEs),and deaths,and the frequency of treatment modification and discontinuation,were collected during therapy and up to 12 wk after treatment completion.The entire study population was included in the intent-to-treat(ITT)analysis.Per-protocol(PP)analysis concerned patients who underwent HCV RNA evaluation 12 wk after completing treatment.RESULTS Among patients with mental illness,there was a significantly higher percentage of men,treatmentnaive patients,obese,human immunodeficiency virus and hepatitis B virus-coinfected,patients with cirrhosis,and those infected with genotype 3(GT3)while infection with GT1b was more frequent in the population without psychiatric disorders.The cure rate calculated PP was not significantly different in the two groups analyzed,with a SVR of 96.9% and 97.7%,respectively.Although patients with bipolar disorder achieved a significantly lower SVR,the multivariate analysis excluded it as an independent predictor of treatment non-response.Male sex,GT3 infection,cirrhosis,and failure of previous therapy were identified as independent negative predictors.The percentage of patients who completed the planned therapy did not differ between groups with and without mental disorders.In six patients,symptoms of mental illness(depression,schizophrenia)worsened,of which two discontinued treatments for this reason.New episodes of sleep disorders occurred significantly more often in patients with mental disorders.Patients with mental illness were more frequently lost to follow-up(4.2%vs 2.5%).CONCLUSION DAA treatment is safe and effective in HCV-infected patients with mental disorders.No specific psychiatric diagnosis lowered the chance of successful antiviral treatment. 展开更多
关键词 Hepatitis C Mental disorders Direct-acting antivirals
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城市轨道交通单线服务水平评价方法与应用 被引量:4
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作者 郭延永 刘攀 +1 位作者 吴瑶 马超群 《合肥工业大学学报(自然科学版)》 CAS 北大核心 2017年第3期384-389,共6页
为了对城市轨道交通服务水平进行客观定量的评价,文章构建了城市轨道交通服务水平评价指标体系,提出了基于属性识别理论的城市轨道交通服务水平综合评价模型。将轨道交通服务水平划分为4级,应用变异系数法确定指标权重;根据单指标属性... 为了对城市轨道交通服务水平进行客观定量的评价,文章构建了城市轨道交通服务水平评价指标体系,提出了基于属性识别理论的城市轨道交通服务水平综合评价模型。将轨道交通服务水平划分为4级,应用变异系数法确定指标权重;根据单指标属性测度值与多指标综合属性测度值,利用置信度准则识别城市轨道交通服务水平。以西安市地铁2号线为对象,运用该模型对其服务水平进行了评价,结果表明,西安市轨道交通服务水平属于二级。利用所提出的评价模型,不仅可客观获得城市轨道交通服务水平级别,而且能鉴别影响城市轨道交通服务水平的限制因素,为城市轨道交通运营阶段提高服务水平提供理论支持。 展开更多
关键词 交通工程 城市轨道交通 服务水平 屙隆识别 变异系数
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少数民族青少年韧性素质量表的概化分析 被引量:4
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作者 罗杰 陈维 +1 位作者 潘运 赵守盈 《贵州师范大学学报(自然科学版)》 CAS 2020年第5期93-98,共6页
运用概化理论检验少数民族青少年韧性素质量表(EMARDI)的心理测量学性能,采用EMARDI对贵州、云南和四川地区的2241名少数民族青少年进行问卷调查。结果显示:EMARDI具有较好的测量学属性,各因子(高阶与低阶因子)和全量表的概化系数和可... 运用概化理论检验少数民族青少年韧性素质量表(EMARDI)的心理测量学性能,采用EMARDI对贵州、云南和四川地区的2241名少数民族青少年进行问卷调查。结果显示:EMARDI具有较好的测量学属性,各因子(高阶与低阶因子)和全量表的概化系数和可靠性指数均达到较好水平,可作为评估我国少数民族青少年韧性素质水平的本土化测评工具;个人支持力及所属低阶因子的分量比例还不尽完善,未来开展EMARDI的修订工作,可着重考虑对该因子的题目进行修正。 展开更多
关键词 韧性素质 少数民族青少年 概化理论
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质子交换膜电解池内氧气泡输运过程特性 被引量:5
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作者 何旭 罗马吉 陈奔 《江苏大学学报(自然科学版)》 EI CAS 北大核心 2021年第2期139-144,共6页
研究了质子交换膜电解池(proton exchange membrane electrolysis cell,PEMEC)阳极流场内的氧气泡运动特性,采用VOF(volume of fluid)方法分析了多孔输运层(porous transport layer,PTL)表面接触角、液态水流速、氧气产生速率及PTL孔径... 研究了质子交换膜电解池(proton exchange membrane electrolysis cell,PEMEC)阳极流场内的氧气泡运动特性,采用VOF(volume of fluid)方法分析了多孔输运层(porous transport layer,PTL)表面接触角、液态水流速、氧气产生速率及PTL孔径对氧气泡在流道中运动特性的影响.结果表明:PTL处理为亲水性有利于气泡脱离,降低表面气体覆盖率,促进液态水到达催化层;高的液态水流速会减小气泡脱离时间及脱离体积,降低PTL表面气体覆盖率及容积含气率,促进气泡从流道中排出;气体生成速率增大会提高流道容积含气率和PTL表面气体覆盖率,不利于电解池的运行;随PTL孔径增大,气泡脱离体积增大,脱离时间先减小后增加. 展开更多
关键词 质子交换膜电解池 VOF方法 两相流 氧气泡 输运特性 多孔输运层
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Expression of p53,Bax and Bcl-2 proteins in hepatocytes in non-alcoholic fatty liver disease 被引量:48
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作者 Anatol Panasiuk Janusz Dzieciol +1 位作者 Bozena Panasiuk Danuta Prokopowicz 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第38期6198-6202,共5页
AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without stea... AIM: To analyze the protein expression essential for apoptosis in liver steatosis. METHODS: The expression of proapoptotic proteins p53, Bax, and antiapoptotic Bcl-2 in hepatocytes with steatosis (SH) and without steatosis (NSH) was evaluated in 84 patients at various stages of non-alcoholic fatty liver disease (NAFLD). RESULTS: Immunohistochemical staining of liver tissue showed the activation of p53 protein in SH and NSH with increased liver steatosis, diminished Bcl-2 and slightly decreased Bax protein. Positive correlation was found between the stage of liver steatosis with p53 expression in SH (r = 0.54, P < 0.01) and NSH (r = 0.49, P < 0.01). The antiapoptotic protein Bcl-2 was diminished together with the advancement of liver steatosis, especially in non-steatosed hepatocytes (r =0.43, P < 001). CONCLUSION: Apoptosis is one of the most important mechanisms leading to hepatocyte elimination in NAFLD. The intensification of inflammation in NAFLD induces proapoptotic protein p53 with the inhibition of antiapoptotic Bcl-2. 展开更多
关键词 基因表达 肝细胞 非酒精性脂肪肝 免疫组织学
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Screening for scoliosis-New recommendations,old dilemmas,no straight solutions 被引量:3
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作者 Maciej Płaszewski Weronika Grantham Ejgil Jespersen 《World Journal of Orthopedics》 2020年第9期364-379,共16页
This opinion review considers the prevailing question of whether to screen or notto screen for adolescent idiopathic scoliosis. New and improved standards ofpeople-oriented care and person-centredness, as well as impr... This opinion review considers the prevailing question of whether to screen or notto screen for adolescent idiopathic scoliosis. New and improved standards ofpeople-oriented care and person-centredness, as well as improved principles ofpreventive screening and guideline development, have been postulated andimplemented in health care systems and cultures. Recommendations addressingscreening for scoliosis differ substantially, in terms of their content, standards ofdevelopment and screening principles. Some countries have discontinued issuingrecommendations. In the last decade, a number of updated and newrecommendations and statements have been released. Systematically developedguidelines and recommendations are confronted by consensus and opinion-basedstatements. The dilemmas and discrepancies prevail. The arguments concentrateon the issues of the need for early detection through screening in terms of theeffectiveness of early treatment, on costs and cost-effectiveness issues, scientificand epidemiologic value of screenings, and the credibility of the sources ofevidence. The problem matter is of global scale and applies to millions of people.It regards clinical and methodological dilemmas, but also the matter of vulnerableand fragile time of adolescence and, more generally, children’s rights. Thedecisions need to integrate people’s values and preferences – screening tests needto be acceptable to the population, and treatments need to be acceptable forpatients. Therefore we present one more crucial, but underrepresented in thediscussion, issue of understanding and implementation of the contemporaryprinciples of person-centred care, standards of preventive screening, andguideline development, in the context of screening for scoliosis. 展开更多
关键词 SCOLIOSIS SCREENING Tests Programs RECOMMENDATIONS Guidelines Principles Benefits HARMS Trustworthiness
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Mesenchymal stem cell therapy for acute radiation syndrome 被引量:2
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作者 Risaku Fukumoto 《Journal of Medical Colleges of PLA(China)》 CAS 2016年第3期117-120,共4页
Acute radiation syndrome affects military personnel and civilians following the uncontrolled dispersal of radiation,such as that caused by detonation of nuclear devices and inappropriate medical treatments.Therefore,t... Acute radiation syndrome affects military personnel and civilians following the uncontrolled dispersal of radiation,such as that caused by detonation of nuclear devices and inappropriate medical treatments.Therefore,there is a growing need for medical interventions that facilitate the improved recovery of victims and patients.One promising approach may be cell therapy,which,when appropriately implemented,may facilitate recovery from whole body injuries.This editorial highlights the current knowledge regarding the use of mesenchymal stem cells for the treatment of acute radiation syndrome,the benefits and limitations of which are under investigation.Establishing successful therapies for acute radiation syndrome may require using such a therapeutic approach in addition to conventional approaches. 展开更多
关键词 Acute radiation syndrome Mesenchymal stem cell Cell therapy Hematopoietic syndrome Gastrointestinal syndrome Military medicine
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Dipper Throated Optimization Algorithm for Unconstrained Function and Feature Selection 被引量:4
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作者 Ali E.Takieldeen El-Sayed M.El-kenawy +1 位作者 Mohammed Hadwan Rokaia M.Zaki 《Computers, Materials & Continua》 SCIE EI 2022年第7期1465-1481,共17页
Dipper throated optimization(DTO)algorithm is a novel with a very efficient metaheuristic inspired by the dipper throated bird.DTO has its unique hunting technique by performing rapid bowing movements.To show the effi... Dipper throated optimization(DTO)algorithm is a novel with a very efficient metaheuristic inspired by the dipper throated bird.DTO has its unique hunting technique by performing rapid bowing movements.To show the efficiency of the proposed algorithm,DTO is tested and compared to the algorithms of Particle Swarm Optimization(PSO),Whale Optimization Algorithm(WOA),Grey Wolf Optimizer(GWO),and Genetic Algorithm(GA)based on the seven unimodal benchmark functions.Then,ANOVA and Wilcoxon rank-sum tests are performed to confirm the effectiveness of the DTO compared to other optimization techniques.Additionally,to demonstrate the proposed algorithm’s suitability for solving complex realworld issues,DTO is used to solve the feature selection problem.The strategy of using DTOs as feature selection is evaluated using commonly used data sets from the University of California at Irvine(UCI)repository.The findings indicate that the DTO outperforms all other algorithms in addressing feature selection issues,demonstrating the proposed algorithm’s capabilities to solve complex real-world situations. 展开更多
关键词 Metaheuristic optimization swarmoptimization feature selection function optimization
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Factors associated with irritable bowel syndrome symptoms in hemodialysis patients 被引量:5
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作者 Bartosz Fiderkiewicz Alicja Rydzewska-Rosoowska +4 位作者 Micha Myliwiec Magdalena Birecka Bozenna Kaczanowska Grazyna Rydzewska Andrzej Rydzewski 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第15期1976-1981,共6页
AIM: To investigate clinical characteristics associated with the presence of irritable bowel syndrome (IBS) symptoms in hemodialysis (HD) patients.METHODS: This was a cross-sectional study. A questionnaire based on th... AIM: To investigate clinical characteristics associated with the presence of irritable bowel syndrome (IBS) symptoms in hemodialysis (HD) patients.METHODS: This was a cross-sectional study. A questionnaire based on the Bowel Disease Questionnaire that records gastrointestinal symptoms was given to 294 patients in 4 dialysis centers. A total of 196 (67%) subjects returned the survey. A multivariable logistic regression model was used to identify factors significantly associated with IBS symptoms. RESULTS: Symptoms compatible with IBS were present in 27 (13.8%) subjects and independently associated with low post-dialysis serum potassium [OR = 0.258, 95% CI (0.075-0.891), P = 0.032], paracetamol use [OR = 3.159, 95% CI (1.214-8.220), P = 0.018], and Kidney Disease Quality of Life (KDQOL) cognitive function score [OR = 0.977, 95% CI (0.956-0.999), P = 0.042]. Univariate regressions were also performed and the reported significance is for multivariate analysis. No association was detected for age, gender, depressed mood, smoking (present or past), body mass index, albumin level, Kt/V, sodium preor post-dialysis level, change in potassium level during HD, proton pump inhibitor or H2 blocker use, aspirin use, residual diuresis, hepatitis B or C infection, diabetes mellitus, marital status and education level. CONCLUSION: This study examined potential risk factors for symptoms compatible with IBS in HD patients and identified an association with paracetamol use, post-dialysis potassium level and KDQOL-cognitive function score. 展开更多
关键词 血液透析 肠道疾病 综合症 LOGISTIC回归模型 症状 患者 对乙酰氨基酚 质子泵抑制剂
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Reversed ethane/ethylene adsorption in a metal–organic framework via introduction of oxygen 被引量:6
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作者 Ling Yang Wei Zhou +6 位作者 Hao Li Ali Alsalme Litao Jia Jiangfeng Yang Jinping Li Libo Li Banglin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第2期593-597,共5页
Separation of ethane from ethylene is a very important but challenging process in the petrochemical industry.Finding an alternative method would reduce the energy needed to make 170 million tons of ethylene manufactur... Separation of ethane from ethylene is a very important but challenging process in the petrochemical industry.Finding an alternative method would reduce the energy needed to make 170 million tons of ethylene manufactured worldwide each year.Adsorptive separation using C2H6-selective porous materials to directly produce high-purity C2H4 is more energy-efficient.We herein report the"reversed C2H6/C2H4 adsorption"in a metal–organic framework Cr-BTC via the introduction of oxygen on its open metal sites.The oxidized Cr-BTC(O2)can bind C2H6 over C2H4 through the active Cr-superoxo sites,which was elucidated by the gas sorption isotherms and density functional theory calculations.This material thus exhibits a good performance for the separation of 50/50 C2H6/C2H4 mixtures to produce 99.99%pure C2H4 in a single separation operation. 展开更多
关键词 Metal–organic frameworks ADSORPTIVE separation Open METAL sites Reversed ethane/ethylene ADSORPTION Density-functional theory calculation BREAKTHROUGH curves
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Comparison of CIM~ C4-HLD monolithic column with Sartobind phenyl membrane column for pIDKE2 purification
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作者 Miladys LIMONTA Lourdes ZUMALACRREGUI +1 位作者 Urska VIDIC Nika LENDERO KRAJNC 《色谱》 CAS CSCD 北大核心 2017年第10期1028-1036,共9页
The main component of the Center for Genetic Engineering and Biotechnology(CIGB)candidate vaccine against Hepatitis C virus(HCV)is the pIDKE2 plasmid.The current designed downstream process for the production of pIDKE... The main component of the Center for Genetic Engineering and Biotechnology(CIGB)candidate vaccine against Hepatitis C virus(HCV)is the pIDKE2 plasmid.The current designed downstream process for the production of pIDKE2 fulfils all regulatory requirements and renders the required quantities of pharmaceuticalgrade plasmid DNA(pDNA)with 95%purity.The advantages of this procedure include high plasmid purity and the elimination of undesirable additives,such as toxic organic extractants and animal-derived enzymes.However,yields and consequently the productivity of the process are low.Previous work demonstrated that the most critical step of the process is the reverse phase chromatography,where conventional porous particle resins are used.Therefore,to increase the process productivity,alternative technologies such as membranes and chromatographic monoliths were tested as alternative options for this critical step.Here,a comparison between the behaviors of CIM~ C4-HLD and Sartobind phenyl matrices was performed.To obtain higher productivities and purities,the dynamic binding capacities and selectivities were evaluated.The results showed that both matrices had a similar capacity for pIDKE2 plasmid,but the separation of pDNA isoforms using CIM~ technology was much better than that with Sartobind.Additionally,the optimal conditions for loading plasmid DNA on a CIMC4-HLD 800-mL monolithic column in a real production process were determined.These optimizations will allow production levels to satisfy the high plasmid consumption demanded by clinical trials. 展开更多
关键词 MEMBRANE MONOLITH downstream processing PLASMID DNA (pDNA) BREAKTHROUGH supercoiled (SC) PLASMID open circular (OC) PLASMID
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