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An Effective Method to Determine the Distribution Boundary of Cobalt-Rich Fe-Mn Crusts on a Guyot: Synchronous Application of Sub-bottom Profiling and Deep-Sea Video Recording 被引量:3
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作者 HeGaowen LiangDonghong +4 位作者 SongChengbin SunXiaoming WuShuigen ZhouJianping ZhangXuehua 《Journal of China University of Geosciences》 SCIE CSCD 2005年第2期178-182,共5页
Determining the upper boundary of the cobalt-rich crust distribution of a guyot is important for estimating the mineral resources available, however, it has also long been an unsolved question. Correlations between th... Determining the upper boundary of the cobalt-rich crust distribution of a guyot is important for estimating the mineral resources available, however, it has also long been an unsolved question. Correlations between the sub-bottom structures, revealed by sub-bottom profiling, and crust distribution can be revealed for the first time by the synchronous application of sub-bottom profiling and deep-sea video recording. The lower boundary of the sediment corresponds with the upper boundary of the crust. By analysis of these two kinds of data, the lower boundary of the sediment can be determined; therefore, the upper boundary of the crust distribution can be deduced. According to this method of analysis, the upper boundary of water depth of crust distribution of a seamount in the western Pacific is about 1 560 m. 展开更多
关键词 sub-bottom profiling deep-sea video recording guyot cobalt-rich ferromanganese crust distribution boundary
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2 kHz High Power Smart Transducer for Acoustic Sub-bottom Profiling Applications 被引量:1
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作者 R. Sathishkumar 《Journal of Marine Science and Application》 2013年第3期361-365,共5页
In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current re... In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response(TCR) at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility(ATF) of National Institute of Ocean Technology(NIOT) for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz. 展开更多
关键词 smart transducer MAGNETOSTRICTION acoustic sub-bottom profiling transmitting current response(TCR)
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Assessment of spermatogenesis in camels via seminiferous tubule staging and testosterone profiling
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作者 Saif Ullah Abdul Quddus +7 位作者 Quanwei Wei Wael Ennab Sheeraz Mustafa Jiahao Sun Rahmani Mohammad Malyar Abdul Baseer Dagan Mao Fangxiong Shi 《Asian pacific Journal of Reproduction》 CAS 2024年第3期133-142,共10页
Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 drom... Objective:To investigate the successive morphological stages of spermatogenesis,hormonal regulation,and testosterone profile in dromedary camel reproduction.Methods:Testicular tissue samples were obtained from 12 dromedary bull camels aged 7 to 8 at a local abattoir.The histological assessment involved tissue processing,hematoxylin and eosin(H&E)staining,and examination under a microscope.Stereological analysis,germ cell identification,and assessment of seminiferous tubules and maturation were conducted.Testosterone assay was performed by radioimmunoassay using blood samples collected at regular intervals.Results:The study revealed 12 phases of the dromedary camel's seminiferous epithelium cycle,highlighting distinct morphological characteristics and cellular processes.Acrosomal migration,maturation,cap formation,and the Golgi-mediated synthesis of proacrosomal vesicles were also explained in dimension,as were the steps of acrosome biogenesis.Spermatids and mature sperm cells were present when spermatogenesis phases were examined.An analysis of the dimensions of seminiferous tubules revealed specific measures for diameter,area,and epithelial height about luminal characteristics.Moreover,there were noticeable variations in the serum testosterone concentrations during the study period,indicating temporal dynamics.Conclusions:This study outlines the spermatogenesis process in dromedary camels across 12 stages,emphasizing cellular dynamics and acrosomal biogenesis.It also provides seminiferous tubule measurements and observes seasonal testosterone fluctuations,offering insights into reproductive regulation and potential strategies for camel breeding conservation. 展开更多
关键词 SPERMATOGENESIS CAMEL Testosterone profile Morphological staging
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A News Media Bias and Factuality Profiling Framework Assisted by Modeling Correlation
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作者 Qi Wang Chenxin Li +3 位作者 Chichen Lin Weijian Fan Shuang Feng Yuanzhong Wang 《Computers, Materials & Continua》 SCIE EI 2024年第11期3351-3369,共19页
News media profiling is helpful in preventing the spread of fake news at the source and maintaining a good media and news ecosystem.Most previous works only extract features and evaluate media from one dimension indep... News media profiling is helpful in preventing the spread of fake news at the source and maintaining a good media and news ecosystem.Most previous works only extract features and evaluate media from one dimension independently,ignoring the interconnections between different aspects.This paper proposes a novel news media bias and factuality profiling framework assisted by correlated features.This framework models the relationship and interaction between media bias and factuality,utilizing this relationship to assist in the prediction of profiling results.Our approach extracts features independently while aligning and fusing them through recursive convolu-tion and attention mechanisms,thus harnessing multi-scale interactive information across different dimensions and levels.This method improves the effectiveness of news media evaluation.Experimental results indicate that our proposed framework significantly outperforms existing methods,achieving the best performance in Accuracy and F1 score,improving by at least 1%compared to other methods.This paper further analyzes and discusses based on the experimental results. 展开更多
关键词 News media profiling factuality BIAS correlated features
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Predicting Age and Gender in Author Profiling: A Multi-Feature Exploration
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作者 Aiman Muhammad Arshad +2 位作者 Bilal Khan Sadique Ahmad Muhammad Asim 《Computers, Materials & Continua》 SCIE EI 2024年第5期3333-3353,共21页
Author Profiling (AP) is a subsection of digital forensics that focuses on the detection of the author’s personalinformation, such as age, gender, occupation, and education, based on various linguistic features, e.g.... Author Profiling (AP) is a subsection of digital forensics that focuses on the detection of the author’s personalinformation, such as age, gender, occupation, and education, based on various linguistic features, e.g., stylistic,semantic, and syntactic. The importance of AP lies in various fields, including forensics, security, medicine, andmarketing. In previous studies, many works have been done using different languages, e.g., English, Arabic, French,etc.However, the research on RomanUrdu is not up to the mark.Hence, this study focuses on detecting the author’sage and gender based on Roman Urdu text messages. The dataset used in this study is Fire’18-MaponSMS. Thisstudy proposed an ensemble model based on AdaBoostM1 and Random Forest (AMBRF) for AP using multiplelinguistic features that are stylistic, character-based, word-based, and sentence-based. The proposed model iscontrasted with several of the well-known models fromthe literature, including J48-Decision Tree (J48),Na飗e Bays(NB), K Nearest Neighbor (KNN), and Composite Hypercube on Random Projection (CHIRP), NB-Updatable,RF, and AdaboostM1. The overall outcome shows the better performance of the proposed AdaboostM1 withRandom Forest (ABMRF) with an accuracy of 54.2857% for age prediction and 71.1429% for gender predictioncalculated on stylistic features. Regarding word-based features, age and gender were considered in 50.5714% and60%, respectively. On the other hand, KNN and CHIRP show the weakest performance using all the linguisticfeatures for age and gender prediction. 展开更多
关键词 Digital forensics author profiling for security AdaBoostM1 random forest ensemble learning
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AMachine Learning Approach to User Profiling for Data Annotation of Online Behavior
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作者 Moona Kanwal Najeed AKhan Aftab A.Khan 《Computers, Materials & Continua》 SCIE EI 2024年第2期2419-2440,共22页
The user’s intent to seek online information has been an active area of research in user profiling.User profiling considers user characteristics,behaviors,activities,and preferences to sketch user intentions,interest... The user’s intent to seek online information has been an active area of research in user profiling.User profiling considers user characteristics,behaviors,activities,and preferences to sketch user intentions,interests,and motivations.Determining user characteristics can help capture implicit and explicit preferences and intentions for effective user-centric and customized content presentation.The user’s complete online experience in seeking information is a blend of activities such as searching,verifying,and sharing it on social platforms.However,a combination of multiple behaviors in profiling users has yet to be considered.This research takes a novel approach and explores user intent types based on multidimensional online behavior in information acquisition.This research explores information search,verification,and dissemination behavior and identifies diverse types of users based on their online engagement using machine learning.The research proposes a generic user profile template that explains the user characteristics based on the internet experience and uses it as ground truth for data annotation.User feedback is based on online behavior and practices collected by using a survey method.The participants include both males and females from different occupation sectors and different ages.The data collected is subject to feature engineering,and the significant features are presented to unsupervised machine learning methods to identify user intent classes or profiles and their characteristics.Different techniques are evaluated,and the K-Mean clustering method successfully generates five user groups observing different user characteristics with an average silhouette of 0.36 and a distortion score of 1136.Feature average is computed to identify user intent type characteristics.The user intent classes are then further generalized to create a user intent template with an Inter-Rater Reliability of 75%.This research successfully extracts different user types based on their preferences in online content,platforms,criteria,and frequency.The study also validates the proposed template on user feedback data through Inter-Rater Agreement process using an external human rater. 展开更多
关键词 User intent CLUSTER user profile online search information sharing user behavior search reasons
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Genomic profiling of colorectal cancer in large-scale Chinese patients:amplification and somatic mutations in ERBB2
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作者 YUZHI LIU EVELYNE BISCHOF +5 位作者 ZHIQIN CHEN JIAHUAN ZHOU BEI ZHANG DING ZHANG YONG GAO MING QUAN 《Oncology Research》 SCIE 2024年第9期1429-1438,共10页
Objectives:Human epidermal growth factor receptor 2(HER2)-targeted therapies have demonstrated potential benefits for metastatic colorectal cancer(mCRC)patients with HER2 amplification,but are not satisfactory in case... Objectives:Human epidermal growth factor receptor 2(HER2)-targeted therapies have demonstrated potential benefits for metastatic colorectal cancer(mCRC)patients with HER2 amplification,but are not satisfactory in cases of HER2 mutant CRCs.Methods:Consequently,further elucidation of amplifications and somatic mutations in erythroblastic oncogene B-2(ERBB2)is imperative.Comprehensive genomic profiling was conducted on 2454 Chinese CRC cases to evaluate genomic alterations in 733 cancer-related genes,tumor mutational burden,microsatellite instability,and programmed death ligand 1(PD-L1)expression.Results:Among 2454 CRC patients,85 cases(3.46%)exhibited ERBB2 amplification,and 55 cases(2.24%)carried ERBB2 mutation.p.R678Q(28%),p.V8421(24%),and p.S310F/Y(12%)were the most prevalent of the 16 detected mutation sites.In comparison to the ERBB2 altered(alt)group,KRAS/BRAF mutations were more prevalent in ERBB2 wild-type(wt)samples(ERBB2wt vs.ERBB2alt,KRAS:50.9%vs.25.6%,p<0.05;BRAF:8.5%vs.2.3%,p<0.05).32.7%(18/55)of CRCs with ERBB2 mutation exhibited microsatellite instability high(MSI-H),while no cases with HER2 amplification displayed MSI-H.Mutant genes varied between ERBB2 copy number variation(CNV)and ERBB2 single nucleotide variant(SNV);TP53 alterations tended to co-occur with ERBB2 amplification(92.3%)as opposed to ERBB2 mutation(58.3%).KRAS and PIK3CA alterations were more prevalent in ERBB2 SNV cases(KRAS/PIK3CA:45.8%/31.2%)compared to ERBB2 amplification cases(KRAS/PIK3CA:14.1%/7.7%).Conclusion:Our study delineates the landscape of HER2 alterations in a large-scale cohort of CRC patients from China.These findings enhance our understanding of the molecular features of Chinese CRC patients and offer valuable implications for further investigation. 展开更多
关键词 Colorectal cancer ERBB2 HER2 Human epidermal growth factor receptor 2 Genetic profiling Precision oncology
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ABMRF:An Ensemble Model for Author Profiling Based on Stylistic Features Using Roman Urdu
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作者 Aiman Muhammad Arshad +3 位作者 Bilal Khan Khalil Khan Ali Mustafa Qamar Rehan Ullah Khan 《Intelligent Automation & Soft Computing》 2024年第2期301-317,共17页
This study explores the area of Author Profiling(AP)and its importance in several industries,including forensics,security,marketing,and education.A key component of AP is the extraction of useful information from text... This study explores the area of Author Profiling(AP)and its importance in several industries,including forensics,security,marketing,and education.A key component of AP is the extraction of useful information from text,with an emphasis on the writers’ages and genders.To improve the accuracy of AP tasks,the study develops an ensemble model dubbed ABMRF that combines AdaBoostM1(ABM1)and Random Forest(RF).The work uses an extensive technique that involves textmessage dataset pretreatment,model training,and assessment.To evaluate the effectiveness of several machine learning(ML)algorithms in classifying age and gender,including Composite Hypercube on Random Projection(CHIRP),Decision Trees(J48),Na飗e Bayes(NB),K Nearest Neighbor,AdaboostM1,NB-Updatable,RF,andABMRF,they are compared.The findings demonstrate thatABMRFregularly beats the competition,with a gender classification accuracy of 71.14%and an age classification accuracy of 54.29%,respectively.Additional metrics like precision,recall,F-measure,Matthews Correlation Coefficient(MCC),and accuracy support ABMRF’s outstanding performance in age and gender profiling tasks.This study demonstrates the usefulness of ABMRF as an ensemble model for author profiling and highlights its possible uses in marketing,law enforcement,and education.The results emphasize the effectiveness of ensemble approaches in enhancing author profiling task accuracy,particularly when it comes to age and gender identification. 展开更多
关键词 Machine learning author profiling AdaBoostM1 random forest ensemble learning text classification
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Depth profiling of arsenian pyrite in Carlin-type ores through wet chemistry 被引量:1
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作者 Meizhi Yang Quan Wan +4 位作者 Xin Nie Suxing Luo Yuhong Fu Ping Zeng Wenqi Luo 《Acta Geochimica》 EI CAS CSCD 2023年第2期256-265,共10页
Enrichment of As and Au at the overgrowth rims of arsenian pyrite is a distinctive feature of Carlin-type gold ores.Revealing distribution of such key elements in high resolution is of fundamental importance yet often... Enrichment of As and Au at the overgrowth rims of arsenian pyrite is a distinctive feature of Carlin-type gold ores.Revealing distribution of such key elements in high resolution is of fundamental importance yet often proves challenging.In this study,repeated non-oxidative acid etching of ore samples from Shuiyindong gold deposit was applied to enable elemental depth profiling of goldbearing arsenian pyrite grains.ICP-OES and AAS were used to determine the dissolved Fe,As,and Au concentrations in each of the etching solutions,and XPS was carried out to exam the etched mineral surfaces.In contrast to conventional ion beam etching that may cause substantial sample damage,our acid etching method does not seem to significantly alter the composition and chemical state of the samples.The etched depths directly converted from the measured elemental concentrations can reproducibly reach a very high resolution of~1 nm,and can be conveniently controlled through varying the etching time.While the Fe and As depth profiles consistently reflect the surface oxidation property of arsenian pyrite,the Au profile displaying an obvious upward trend reveals the ore fluid evolution at the late stage of mineralization.Based on our experimental results,we demonstrate that our wet chemistry method is capable of effective depth profiling of gold ore and perhaps other geological samples,with advantages surpassing many instrumental techniques including negligible sample damage,nanoscale resolution as well as isotropic etching. 展开更多
关键词 Wet chemistry Acid etching Depth profiling Carlin-type gold deposits Arsenian pyrite
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DMMIC derivatization-assisted liquid chromatography-mass spectrometry method for metabolite profiling of the glutathione anabolic pathway in esophageal cancer tissues and cells 被引量:1
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作者 Li Liu Yu-Han Lu +5 位作者 Min-Dan Wang Qun-Fei Zhao Xiu-Ping Chen Hang Yin Chen-Guo Feng Fang Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第11期1365-1373,共9页
In this work,a new pyrylium derivatization-assisted liquid chromatography-mass spectrometry(LC-MS)method was developed for metabolite profiling of the glutathione anabolic pathway(GAP)in cancer tissues and cells.The p... In this work,a new pyrylium derivatization-assisted liquid chromatography-mass spectrometry(LC-MS)method was developed for metabolite profiling of the glutathione anabolic pathway(GAP)in cancer tissues and cells.The pyrylium salt of 6,7-dimethoxy-3-methyl isochromenylium tetrafluoroborate(DMMIC)was used to label the amino group of metabolites,and a reductant of dithiothreitol(DTT)was employed to stabilize the thiol group.By combining DMMIC derivatization with LC-MS,it was feasible to quantify the 13 main metabolites on the GAP in complex biological samples,which had good linearity(R^(2)=0.99810.9999),precision(interday precision of 1.6%e19.0%and intraday precision of 1.4%e19.8%)and accuracy(83.4%-115.7%).Moreover,the recovery assessments in tissues(82.5%e107.3%)and in cells(98.1%e118.9%)with GSH-^(13)C2,^(15)N,and Cys-^(15)N demonstrated the reliability of the method in detecting tissues and cells.Following a methodological evaluation,the method was applied successfully to investigate difference in the GAP between the carcinoma and para-carcinoma tissues of esophageal squamous cell carcinoma(ESCC)and the effect of p-hydroxycinnamaldehyde(CMSP)on the GAP in KYSE150 esophageal cancer cells.The results demonstrate that the developed method provides a promising new tool to elucidate the roles of GAP in physiological and pathological processes,which can contribute to research on drugs and diseases. 展开更多
关键词 Glutathione anabolic pathway Metabolite profiling DMMIC derivatization LC-MS Esophageal squamous cell carcinoma p-Hydroxycinnamaldehyde KYSE-150cell
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Thermal integrity profiling of cast-in-situ piles in sand using fiber-optic distributed temperature sensing 被引量:1
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作者 Jing Wang Honghu Zhu +4 位作者 Daoyuan Tan Zili Li Jie Li Chao Wei Bin Shi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第12期3244-3255,共12页
Defects in cast-in-situ piles have an adverse impact on load transfer at the pile‒soil interface and pile bearing capacity. In recent years, thermal integrity profiling (TIP) has been developed to measure temperature ... Defects in cast-in-situ piles have an adverse impact on load transfer at the pile‒soil interface and pile bearing capacity. In recent years, thermal integrity profiling (TIP) has been developed to measure temperature profiles of cast-in-situ piles, enabling the detection of structural defects or anomalies at the early stage of construction. However, using this integrity testing method to evaluate potential defects in cast-in-situ piles requires a comprehensive understanding of the mechanism of hydration heat transfer from piles to surrounding soils. In this study, small-scale model tests were conducted in laboratory to investigate the performance of TIP in detecting pile integrity. Fiber-optic distributed temperature sensing (DTS) technology was used to monitor detailed temperature variations along model piles in sand. Additionally, sensors were installed in sand to measure water content and matric suction. An interpretation method against available DTS-based thermal profiles was proposed to reveal the potential defective regions. It shows that the temperature difference between normal and defective piles is more obvious in wet sand. In addition, there is a critical zone of water migration in sand due to the water absorption behavior of cement and temperature transfer-induced water migration in the early-age concrete setting. These findings could provide important insight into the improvement of the TIP testing method for field applications. 展开更多
关键词 Geotechnical monitoring Distributed temperature sensing(DTS) Pile defect Fiber-optic thermal integrity profiling(FO-TIP) Heat transfer Pile‒soil interface
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Molecular Profiling of Sugarcane Wine, a Traditional Fermented Beverage (Loungouila) from Madingou
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作者 Yannick Frédéric Okouakoua Nicaise Saturnin Mokémiabeka +4 位作者 Christian Aimé Kayath Moïse Doria Kaya-Ongoto Stech Anomène Eckzechel Nzaou Nkalla Lambi Ndelani Etienne Nguimbi 《American Journal of Molecular Biology》 2023年第4期197-212,共16页
A number of studies reported that traditional fermented beverages possessed pharmaceutical biomolecules involved in biocatalysis for good therapeutic effects on various pathology including tumor, diabetes, inflammatio... A number of studies reported that traditional fermented beverages possessed pharmaceutical biomolecules involved in biocatalysis for good therapeutic effects on various pathology including tumor, diabetes, inflammation, and obesity. This dimension of understanding is the prerogative of the biomolecular profile found in these fermented foods and beverages. The current work aimed to study the postfermentation molecular profile of the Congolese fermented beverage (Lougwila). The determination of pH, the acidity titratable, the distillation of sugar cane, the determination of total polyphenols and flavonoids and the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) have been used. As results, the fermenting sugar cane juice at room temperature for a period of seven days, leading to a decrease of the pH value to 4.25 ± 0.10 and increase in titratable acidity and alcohol content of at least 6.421 g/L (w/v) and 7% respectively. The polyphenol concentration of Loungouila increase from 14.9 to 20.5 mg Eq AG/g Ms after 10 days of fermentation. The flavonoid concentration varies from 1.70 to 5.22 mg Eq Cat/g Ms. among 46 isolates of Bacillus species, 55% (25/45) were able to show a very interesting clear zones in terms of cellulolytic activity with the percentage ranging from 37.3% to 83.9%, and 41.3% of amylolytic activity for the percentage ranging from 52.02% to 75%. 65.21% (30/46) of the isolates tested were found to be positive by the caseinolytic test with zones of inhibition ranging in diameter from 1.10 ± 0.09 to 3.25 ± 0.07 cm. In addition to the determination of biomolecule profile, 34.78% (16/46) of Bacillus isolates were able to produce biosurfactants with percentages ranging from 14% to 100%. Proteomic profiling of Loungouila has been investigated by using MALDI-TOF Technique. Short sequences showed 100% identity and were associated with AprE, SubC, amyE, NprE, CelA, lytF, Mut, and ykfC proteins. The National Center for Biotechnology Information (NCBI) allowed to associate short sequences to Bacillus species. 展开更多
关键词 Loungouila Molecular profiling BACILLUS POLYPHENOL Flovanoids BIOSURFACTANT
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三维薛定谔方程组的线性Profile分解
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作者 韩依洋 廖梦兰 《湘潭大学学报(自然科学版)》 CAS 2024年第2期44-49,共6页
为了研究线性薛定谔方程组解Strichartz估计的紧性缺失问题,针对H•^(1)(R^(3))×H•^(1)(R^(3))中的三维线性薛定谔方程组的有界解向量序列,使用解序列的Profile分解方法,构造为解向量子列的(1/√h_(n))U(t-t_(n))/h_(n)^(2),(x-x_(n... 为了研究线性薛定谔方程组解Strichartz估计的紧性缺失问题,针对H•^(1)(R^(3))×H•^(1)(R^(3))中的三维线性薛定谔方程组的有界解向量序列,使用解序列的Profile分解方法,构造为解向量子列的(1/√h_(n))U(t-t_(n))/h_(n)^(2),(x-x_(n))/h_(n)类型的Profile分解和.其中,U是线性薛定谔方程组的解向量,在Strichartz范数估计下具有一个很小的余项.首先确定伸缩变换参数序列族,利用傅里叶变换和迭代的思想确定Profile分解族.其次验证了Profile分解和的收敛性,说明了Strichartz范数下余项的收敛性.最后证明了当线性薛定谔方程组的解序列有界时,都可以分解为解向量子列和的形式. 展开更多
关键词 薛定谔方程组 profile分解 STRICHARTZ估计 Sobolev嵌入 傅里叶变换
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Deep learning approaches to recover the plasma current density profile from the safety factor based on Grad–Shafranov solutions across multiple tokamaks
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作者 张瀚予 周利娜 +6 位作者 刘钺强 郝广周 王硕 杨旭 苗雨田 段萍 陈龙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期17-28,共12页
Many magnetohydrodynamic stability analyses require generation of a set of equilibria with a fixed safety factor q-profile while varying other plasma parameters.A neural network(NN)-based approach is investigated that... Many magnetohydrodynamic stability analyses require generation of a set of equilibria with a fixed safety factor q-profile while varying other plasma parameters.A neural network(NN)-based approach is investigated that facilitates such a process.Both multilayer perceptron(MLP)-based NN and convolutional neural network(CNN)models are trained to map the q-profile to the plasma current density J-profile,and vice versa,while satisfying the Grad–Shafranov radial force balance constraint.When the initial target models are trained,using a database of semianalytically constructed numerical equilibria,an initial CNN with one convolutional layer is found to perform better than an initial MLP model.In particular,a trained initial CNN model can also predict the q-or J-profile for experimental tokamak equilibria.The performance of both initial target models is further improved by fine-tuning the training database,i.e.by adding realistic experimental equilibria with Gaussian noise.The fine-tuned target models,referred to as fine-tuned MLP and fine-tuned CNN,well reproduce the target q-or J-profile across multiple tokamak devices.As an important application,these NN-based equilibrium profile convertors can be utilized to provide a good initial guess for iterative equilibrium solvers,where the desired input quantity is the safety factor instead of the plasma current density. 展开更多
关键词 plasma equilibrium deep learning safety factor profile current density profile TOKAMAK
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Profile of Amoebic vs. Pyogenic Liver Abscess and Comparison of Demographical, Clinical, Radiological, and Laboratory Profiles of These Patients from Three Secondary Care Centers in Senegal
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作者 Agbogbenkou Tevi Dela-Dem Lawson Daouda Thioub +2 位作者 Ndiaga Mbengue Ndeye Amy Sarr Sylvie Audrey Diop 《Advances in Infectious Diseases》 CAS 2024年第3期595-605,共11页
Background: Liver abscess (LA) is a suppurated collection in the hepatic parenchyma. In Africa, liver abscesses are most often of amoebic origin, but more recently, the rate of pyogenic liver abscesses (PLA) has incre... Background: Liver abscess (LA) is a suppurated collection in the hepatic parenchyma. In Africa, liver abscesses are most often of amoebic origin, but more recently, the rate of pyogenic liver abscesses (PLA) has increased. Objective: to assess the epidemiological characteristics, clinical features, biological radiological findings, and outcomes of patients with PLA and with amebic liver abscess (ALA) in order to determine the potential factors that may help improve diagnosis and treatment for LA in the context of secondary care centers with limited medical supports. Methods: Retrospective review of LA diagnosed and treated at three secondary care centers in Thiès over 11 years. Results: 61 patients, were included, 52.45% had ALA and 47.54% had PLA. Males were predominant (79.31% in PLA vs 65.63% in ALA, p = 0.2). The median age was 38 years for the PLA group vs 39 years for the ALA group (p = 0.4). In both groups, the most common symptom was right upper abdominal pain (81.97%), hepatomegaly (81.97%). The PLA group had a higher prevalence of fever (79.31% vs 46.88%, p = 0,009), chills (51.72% vs 18.75%, p = 0.007), right basi-thoracic pain (55.17% vs 28.13%, p = 0.032), and jaundice (55.17% vs 28%, p = 0.032). There was no difference in radiological features between PLA and ALA. Patients with PLA had a higher level of White blood cell (20.600 vs 15.400, p = 0.014). The most common bacteria identified in PLA were Escherichia coli (58.8%). All patients had received antibiotic therapy, which was combined with aspiration puncture (37.3%), transcutaneous drainage (43.3%), and surgery (9.0%). Seven patients had received antibiotic therapy alone and all had amoebic abscesses. Elsewhere, the occurrence of complications was higher in PLA cases (75.86% vs 37.5%, p = 0.003). The overall hospital mortality rate was 13.11%, higher in cases of PLA (24.14% vs 3.13%, p = 0.022). Conclusion: Clinical and biological features were more severe in PLA. But radiological features cannot be used to distinguish between PLA and ALA. 展开更多
关键词 profilE Liver Abscess Amoebic PYOGENIC Senegal
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Three-Channel Interference Interpretation of Fano Profile
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作者 李波 李天钧 +3 位作者 马子茹 王希源 黄新朝 朱林繁 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期30-34,共5页
Fano resonance is a ubiquitous phenomenon, and it is commonly interpreted as a two-channel interference of the discrete and continuous channels. The present work investigates the Fano profile from a perspective of the... Fano resonance is a ubiquitous phenomenon, and it is commonly interpreted as a two-channel interference of the discrete and continuous channels. The present work investigates the Fano profile from a perspective of the temporal evolution of the wave function. By exciting the atom with a δ pulse and calculating the evolution of the wave function, the Fano formula is deduced. The results clearly show that the Fano resonance is of a three-channel interference, which is different from the traditional understanding. The three channels are revealed as the groundcontinuum, ground-discrete-continuum, and a previously unmentioned third channel, i.e., ground-continuumdiscrete-continuum. The present three-channel interpretation can be easily generalized to other physical systems,contributing to a deeper understanding of the Fano profile. 展开更多
关键词 FUNCTION profilE CONTINUUM
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Genomic Profile of SARS-COV-2 Associated with COVID-19 Outbreaks in N’Djamena, Chad
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作者 Mathieu Hota Henry Yandai Fissou +2 位作者 Dezoumbe Koutaya Djallaye Djimtoïbaye Mahamat Moussa Ali 《Advances in Bioscience and Biotechnology》 CAS 2024年第7期432-442,共11页
Background: SARS-CoV-2 has circulated worldwide with dramatic consequences. In Chad, we have no data reported of variants. The aim of this study was to identify the SARS-CoV-2 variants that circulated during the epide... Background: SARS-CoV-2 has circulated worldwide with dramatic consequences. In Chad, we have no data reported of variants. The aim of this study was to identify the SARS-CoV-2 variants that circulated during the epidemic from 2020 to 2021. Methods: This is a cross-sectional, descriptive study carried out between 2020 and 2021. Samples from patients with suspected COVID-19 were tested in five laboratories in N’Djamena. One hundred quality samples of the positives were sequenced in Kinshasa using Oxford nanopore technologies minion and the Protocol Midnight SARS-CoV2. Data were processed using Excel version 16 software. Results: Of the 100 samples sequenced, 77 (77%) produced sequences, 23 (23%) did not. The genomic profiles were wild-type Wuhan and minor mutations (19A, 19B (A), 20A (B.1, B.2), 20B (AV.1), 20D (B.1.1.1 /C.36), 20C), variant of concern Alpha (20I), variant of concern Delta (21A/J), variant of interest Eta (21D), variant of concern Omicron (21K) and unclassified variant under surveillance (B.1.640). Of these variants, the maximums were detected in patients aged 26 - 35 with 30.26% and 25.26% in 36 - 45. However, 24.67% were in travelers and 75.32% in residents, 35.06% in those vaccinated against COVID-19 and 62.33% in non-vaccinates. The estimated case-fatality rate was 2.44% (107/4374). Conclusion: This work has provided preliminary data on COVID-19 and SARS-CoV-2 variants circulating during the 2020-2021 epidemics in Chad. 展开更多
关键词 COVID-19 SARS-CoV-2 Genomic profile VARIANT CHAD
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Baseline design of the KunLun Turbulence Profiler instrument
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作者 Xiaohui Guo Yi Hu +2 位作者 Jing Li Xu Yang Zhengzhou Yan 《Astronomical Techniques and Instruments》 CSCD 2024年第4期218-226,共9页
Adaptive optics systems are the most powerful tools to counteract the image blurring caused by atmospheric turbulence,allowing ground-based telescopes to capture high-resolution images.A critical parameter influencing... Adaptive optics systems are the most powerful tools to counteract the image blurring caused by atmospheric turbulence,allowing ground-based telescopes to capture high-resolution images.A critical parameter influencing adaptive optics system performance is the atmospheric refractive index structure constant,C_(n)^(2),which characterizes the intensity of atmospheric optical turbulence as a function of altitude.Given its simplicity,the lunar scintillometer is the preferred method for detecting atmospheric turbulence in challenging environments like Dome A in Antarctica,where sites are still in the developmental stages and local environmental conditions are extremely harsh.However,optimizing the performance of such instruments requires carefully determining the baseline configuration of photon sensors according to each site's specific optical turbulence profile characteristics.This study uses a Monte Carlo method to identify the optimal configuration for the KunLun Turbulence Profiler(KLTP),an instrument comparable to the lunar scintillometer,developed for use at Dome A.Simulations conducted using the obtained optimal baseline configuration recovered three different model optical turbulence profiles,demonstrating the effectiveness of our method in obtaining an optimal baseline configuration.Our approach can be easily applied to baseline design for similar turbulence profilers at other sites. 展开更多
关键词 KunLun Turbulence profiler Monte Carlo Simulation Turbulence profile
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Profile of Full-Term Births in Maternity Wards of Public Hospitals in Douala Cameroon
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作者 Henri Essome Merlin Boten Bounyom +14 位作者 Astrid Ndolo Kondo Ingrid Doriane Ofakem Ilick Fulbert Mangala Nkwele Irène Cyrielle Edjoa Mboe Michel Roger Ekono Alphonse Ngalame Nyong Robert Tchounzou Moustapha Bilkissou Junie Ngaha Yaneu Marga Vanina Ngono Akam Gervais Mounchikpou Ngouhouo Grâce Tocki Toutou Théophile Nana Njamen Valère Mve Koh Pascal Foumane 《Open Journal of Obstetrics and Gynecology》 2024年第5期705-720,共16页
Introduction: Pregnancy as much as childbirth constitutes a risky situation, potentially fraught with sometimes dramatic complications: maternal death. Objective: We conducted this study with the aim of establishing t... Introduction: Pregnancy as much as childbirth constitutes a risky situation, potentially fraught with sometimes dramatic complications: maternal death. Objective: We conducted this study with the aim of establishing the profile of those giving birth in our context with the aim to anticipate operationally in the future on morbidity but more on maternal deaths. Methodology: We conducted, using a structured questionnaire, a prospective descriptive study in representative maternity wards in the city of Douala;the study variables were socio-economic, anthropometric, obstetrical and clinical. Statistical analyses were carried out with CS Pro 7.3 and SPSS version 25.0 software. The Student, Chi-square and Fischer tests were used to compare the means of the variables and the percentages. Results: We recruited 305 births for our study. The average age of our births was 28.7 years ± 6.1 with an average height of 161.6 cm ± 5.06;an average body mass index at the start of pregnancy of 28.0 kilograms/square meter and 31.3 kilograms/square meter at delivery;the average weight gain was 8.4 g ± 5.37;an average gestation of 2.84±1.90;an average parity of 2.2 ± 2.1 with an average birth interval of 27.7 months ± 23.7. The average gestational age was 39.2 weeks ± 1.21 with pregnancy pathology dominated by malaria;85.9% began their prenatal follow-up before the 14th week of amenorrhea. Conclusion: The profile of childbirth in urban Cameroon does not seem potentially dystocic compared to that of the same regional and racial area. 展开更多
关键词 profilE Delivery TERM MALARIA Douala
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Morphological,phylogenetic and metabolite profile of Prorocentrum clipeus,a newly recorded epiphytic dinoflagellate in the northern Yellow Sea
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作者 Ruifang Wang Mengmeng Tong +10 位作者 Shiwen Zhou Junjie Zheng Wenguang Zhang Xinfeng Dai Douding Lu Jiarong Hu Tianze Leng Qinglin Mu Zhongyong Yan Jiangning Zeng Pengbin Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期128-141,共14页
More than 30 species of benthic Prorocentrum have been identified,some of which produce okadaic acid(OA)and its derivatives,dinophysistoxins(DTXs),which cause diarrhetic shellfish poisoning(DSP).Increasing numbers of ... More than 30 species of benthic Prorocentrum have been identified,some of which produce okadaic acid(OA)and its derivatives,dinophysistoxins(DTXs),which cause diarrhetic shellfish poisoning(DSP).Increasing numbers of benthic Prorocentrum species have been reported in tropical and subtropical waters of China.In contrast,only a few benthic Prorocentrum species have been reported in temperate waters.In this study,morphological descriptions obtained using light microscopy,scanning electron microscopy and molecular characterization of one Prorocentrum clipeus strain isolated from the Yellow Sea are presented.Prorocentrum clipeus cells were nearly circular in shape,with a collar,ridge,and one protrusion.The periflagellar area was wide U-shaped,with two curved projections on platelet 1a.Nine periflagellar platelets of different sizes were observed.The morphology closely fits that of the species isolated from other locations.Phylogenetic analysis based on the molecular sequences of the small subunit(SSU)rDNA,internal transcribed spacer(ITS),and large subunit(LSU)rDNA was performed.A comprehensive metabolomic analysis incorporating target,suspect and non-target screenings was first applied to investigate the intracellular and extracellular metabolite profiles of the current isolate of P.clipeus.According to the results of the target and suspect screenings,179 metabolites or toxins produced by DSP-related algal species,including OA,dinophysistoxin-1(DTX1),dinophysistoxin-2(DTX2)and pectenotoxin-2(PTX2),were not detected.Non-target screening involving feature-based molecular networking(FBMN)provided a global view of major metabolites produced by the P.clipeus DF128 strain and revealed 23 clusters belonging to at least 13 compound classes,with organometallic compounds,lipids and lipid-like molecules,phenylpropanoids and polyketides,and benzenoids as major types.To date,this is the first record of the characterization of P.clipeus in samples from Chinese waters.Our results support the wide distribution of epibenthic Prorocentrum species. 展开更多
关键词 PROROCENTRUM taxonomy PHYLOGENY metabolite profiling Yellow Sea
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