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Diagnostic Accuracy of Computerized Bowel Sound Analysis with Non-Invasive Devices for Irritable Bowel Syndrome:A Systematic Review and Meta-Analysis
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作者 Xia-Xiao Yan Yue-Lun Zhang +2 位作者 Yu-Pei Zhang Ying-Yun Yang Dong Wu 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第2期122-130,共9页
Objective To assess the diagnostic accuracy of bowel sound analysis for irritable bowel syndrome(IBS)with a systematic review and meta-analysis.Methods We searched MEDLINE,Embase,the Cochrane Library,Web of Science,an... Objective To assess the diagnostic accuracy of bowel sound analysis for irritable bowel syndrome(IBS)with a systematic review and meta-analysis.Methods We searched MEDLINE,Embase,the Cochrane Library,Web of Science,and IEEE Xplore databases until September 2023.Cross-sectional and case-control studies on diagnostic accuracy of bowel sound analysis for IBS were identified.We estimated the pooled sensitivity,specificity,positive likelihood ratio,negative likeli-hood ratio,and diagnostic odds ratio with a 95% confidence interval(CI),and plotted a summary receiver operat-ing characteristic curve and evaluated the area under the curve.Results Four studies were included.The pooled diagnostic sensitivity,specificity,positive likelihood ratio,nega-tive likelihood ratio,and diagnostic odds ratio were 0.94(95%CI,0.87‒0.97),0.89(95%CI,0.81‒0.94),8.43(95%CI,4.81‒14.78),0.07(95%CI,0.03‒0.15),and 118.86(95%CI,44.18‒319.75),respectively,with an area under the curve of 0.97(95%CI,0.95‒0.98).Conclusions Computerized bowel sound analysis is a promising tool for IBS.However,limited high-quality data make the results'validity and applicability questionable.There is a need for more diagnostic test accuracy studies and better wearable devices for monitoring and analysis of IBS. 展开更多
关键词 irritable bowel syndrome bowel sound analysis diagnostic accuracy systematic review META-analysis
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Sound Transmission Loss Analysis of a Double Plate-Acoustic Cavity Coupling System with In-Plane Functionally Graded Materials
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作者 Changzhong Chen Mingfei Chen Wenliang Yu 《Journal of Applied Mathematics and Physics》 2024年第6期2333-2345,共13页
In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The fu... In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL. 展开更多
关键词 Isogeometric analysis sound Transmission Loss Double-Plate System Functionally Graded Materials Acoustic Structure Coupling
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Analysis of Young Girls’Eagerness to Spend for Disney Virtual Characters Based on Marketing Mix Theory
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作者 HUANG Xiaoyu 《Psychology Research》 2023年第4期188-194,共7页
A virtual character is a design of a fictitious creature with distinctive characteristics created by people,and Disney virtual characters are those Intellectual Property(IP)images that appeared in Disneyland and Disne... A virtual character is a design of a fictitious creature with distinctive characteristics created by people,and Disney virtual characters are those Intellectual Property(IP)images that appeared in Disneyland and Disney movies.This investigation aimed to explore why many younger females are keen to spend money on Disney virtual characters.This paper adopted the Marketing Mix Theory strategy(product,price,placement,and promotion(4P)),and the SWOT analysis method has been utilized.This paper investigated the relationship between the 4Ps and consumers’purchasing intentions,and it turned out that unique design and effective promotion in this Disney case would promote consumers’purchase intention,while the higher price and less accessible placements affected their purchase intentions.Thus,the high price and limited places somewhat inhibit customers’desire to buy;due to the attractiveness of the product itself and the promotion on the internet,the target consumers are still willing to consume. 展开更多
关键词 Marketing Mix theory 4P SWOT(strengths WEAKNESS opportunities threats)analysis DISNEY virtual characters
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Analysis on the Main Botanical Characters of 41 Cucurbita moschata Varieties 被引量:1
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作者 韩小霞 胡新军 +2 位作者 粟建文 袁祖华 李勇奇 《Agricultural Science & Technology》 CAS 2015年第9期1891-1896,共6页
In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, ... In order to scientifically evaluate the values of Cucurbita moschata cultivars, main botanical characters including the initial flowering date, the first fruiting node, fruit length, fruit stem length, stem diameter, internode length, the transverse and longitudinal diameters of the largest leaf, single fruit weight, flesh thickness and soluble solid content of 41 cultivars were measured for conducting diversity, correlation and cluster analysis. The results revealed that the pumpkin cultivars showed large variations in fruit stem length, single fruit weight, fruit length and flesh thickness, but small variations in initial flowering date. Significant, even highly significant correlations were found among the tested traits. Cluster analysis demonstrated that the 41 old Cucurbita moschata cultivars were divided into three groups, of which multiple traits of Group 1 were better than those in the other two groups. High similarities existed in three groups and the cultivars in each group. This research provided basis for selecting excellent traits and parents for the breeding of hybrids. 展开更多
关键词 Cucurbita moschata Botanical character Diversity analysis Cluster analysis
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Usefulness of Hammering Sound Frequency Analysis as an Evaluation Method for the Prevention of Trouble during Hip Replacement 被引量:5
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作者 R. Sakai K. Uchiyama +4 位作者 N. Takahira M. Kakeshita Y. Otsu K. Yoshida M. Ujihira 《Journal of Biomedical Science and Engineering》 2020年第5期74-80,共7页
In total hip arthroplasty, judgment of the appropriateness of stem hammering is dependent on the experience and feelings of the surgeon and no objective evaluation method has been established. In this study, a frequen... In total hip arthroplasty, judgment of the appropriateness of stem hammering is dependent on the experience and feelings of the surgeon and no objective evaluation method has been established. In this study, a frequency analysis of the hammering sounds in total hip arthroplasty was performed to investigate objective judgment criteria capable of preventing problems during surgery. Stem hammering was applied following the surgeon’s feelings as usual in an operating room. A directional microphone was placed at a distance about 2 m from the surgical field and the peak frequency reaching the maximum amplitude was determined by Fourier analysis. It was clarified that the same peak frequency repeats when appropriate fixation is acquired during surgery, suggesting that intraoperative fracture and postoperative loosening can be prevented by stopping hammering at the time the peak frequency converged. Investigation of changes in the hammering sound frequency may serve as objective judgment criteria capable of preventing problems during surgery. 展开更多
关键词 HIP Replacement Total HIP ARTHROPLASTY HAMMERING sound Frequency analysis Intraoperative Fracture LOOSENING
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Correlation Analysis of Characters of Indica Hybrid Rice with High Content of Amylose 被引量:4
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作者 杨扬 况浩池 +4 位作者 曾正明 罗俊涛 陈光珍 何兴材 付均 《Agricultural Science & Technology》 CAS 2013年第3期475-477,共3页
[Objective] The aim was to research and analyze characters and related correlation of indica hybrid rice containing high amylose. [Method] In the research, major characters of 16 species of groups of {ndica hybrid ric... [Objective] The aim was to research and analyze characters and related correlation of indica hybrid rice containing high amylose. [Method] In the research, major characters of 16 species of groups of {ndica hybrid rice and the correlation were explored in rice belts in Sichuan in 2011. [Result] The variation of chalkiness degree was the highest at 26.8%, followed by rate of head rice at 22.89%; varia- tions of head rice rate and chalkiness degree were lower at 0.72% and 2.61%. In addition, rate of unpolished rice was of significantly negative correlation with chalki- ness degree; rate of chalky rice was of extremely positive correlation with chalkiness degree and gel consistency; chalkiness degree was of significantly positive correla- tion with gel consistency; gel consistency was of significantly negative correlation with protein content; amylose content was of insignificant correlation with gel consis- tency (r=0.166 9) of the 16 hybrid groups. These indicated that gel consistency would be still high as the content of amylose grows (AC≥25%). For example, when the content of anylose in Chuanxiang 29A/Luhui 37, Kangfeng AJ6684, and Lefeng A/SR536 exceeded 27%, the gel consistency was over 80 mm in the research. [Conclusion] The research provides references for improvement of amylose content in breeding hybrid rice. 展开更多
关键词 Higher amylose content Indica hybrid rice characters Correlaiton analysis
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Variation and Cluster Analysis on Leaf Characters from Different Provenance Sources of Polygonum multiflorum Thunb 被引量:2
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作者 韦艳梅 王凌晖 +2 位作者 曹福亮 韦山青 梁耀丹 《Agricultural Science & Technology》 CAS 2010年第6期94-98,共5页
[Objective] The aim was to study the variation of leaf characters from different provenance sources of Polygonum multiflorum Thunb,as well as to carry out cluster analysis on P.multiflorum from different provenance so... [Objective] The aim was to study the variation of leaf characters from different provenance sources of Polygonum multiflorum Thunb,as well as to carry out cluster analysis on P.multiflorum from different provenance sources to provide basis for the classification,identification,breeding and improved variety selection of P.multiflorum.[Method] Leaf shape characters of 31 copies of germplasm resources in the major distribution region of the whole country were determined,and the genetic variation of P.multiflorum leaves from different producing areas was analyzed.[Result] The leaf characters of single plant of the same experimental provenance source of P.multiflorum were relatively stable,the variation was mainly found on the single leaf area,1/2 leaf width,leaf width and other indicators;the variation of each leaf character among different provenance sources was obvious,and the variation was mainly found on the single leaf weight,leaf area,1/2 leaf width,leaf length and other indicators.The correlation analysis of each leaf character in P.multiflorum suggested that the single leaf area and single leaf weight showed extremely significant positive correlation with leaf length,1/2 leaf width,leaf width,leaf thickness and leaf stem length,while the single leaf area and single leaf weight showed significant negative correlation with WWR(leaf width/1/2 leaf width)and LWR(leaf length/1/2 leaf length),in addition,several macroscopic leaf characters such as leaf length,1/2 leaf width,leaf width,leaf stem length showed extremely positive correlation.The main component analysis result suggested that the contribution rate of accumulation variance of the front three main components was up to 97.4%,which could better reflect the comprehensive performance of leaf characters of different provenance sources of P.multiflorum.The cluster analysis showed that the experimental 31 copies of P.multiflorum provenance sources should be divided into three classes,the first class was distributed in the Middle,Western of Guizhou,northwestern of Guangxi and western areas with higher altitude;the second class was distributed in Hunan,Hubei,Sichuan,Guangdong and the most area of Guangxi;the third class was distributed in Anhui,Jiangsu and Henan and Shandong.[Conclusion] Cluster analysis of leaf characters indicated that the kinds of provenance sources which the geographical position was closer could be got together.The study had provided a certain basis for the classification of P.multiflorum. 展开更多
关键词 Polygonum multiflorum Thunb Leaf characters VARIATION Cluster analysis
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Vertical root distribution characters of Robinia pseudoacacia on the Loess Plateau in China 被引量:3
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作者 李鹏 赵忠 李占斌 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期87-92,i001,共7页
On the Loess Plateau, water is the main limiting factors for vegetation growth. Root distribution characters have special ecological meaning as it reflected the utilizations of trees to the environments. Even-aged sta... On the Loess Plateau, water is the main limiting factors for vegetation growth. Root distribution characters have special ecological meaning as it reflected the utilizations of trees to the environments. Even-aged stands ofRobinia pseudoacacia on slope lands facing south and north were selected as sampling plots for root distribution investigation. Investigatiing results showed that indicated that on all sites, root biomass decreased with depth, and the distribution depth of fine root was deeper than that of coarser root. The results of variance analysis indicated that there were great differences in root biomass among different diameter classes, and coarser root was the main sources of variance, and the root biomass, especially fine root (?<3mm) biomass on northern exposition sites was bigger than that on southern exposition sites. Analysis of the vertical root distribution parameters, root extinction coefficient, β indicated that the value of β on northern exposition was more than 0.982, while the value of β on southern exposition was less than 0.982, which indicated that the vertical root distribution depth ofRobinia pseudoacacia on southern exposition was deeper than that on southern exposition. And the distribution depth of fine roots (Φ<1mm) was deeper than that of thicker roots(Φ<3mm), which was in favor of the uptake of water and nutrients from deeper layers, helped the trees to adapt the arid environment, and promoted the growth of the upper parts of the tree. Keywords Root diameter classes - Variance analysis - Root extinction coefficient - Vertical distribution characters - Site conditions - Loess Plateau CLC number S792.27.01 Document code A Foundation Item: This research was supported by National Natural Science Foundation of China (30371150 and 40371075).Biography: LI Peng (1974-) male, post: Ph. D. in Northwest Scientific & Technological University of Agriculture and Forestry, Yangling 712100, Shaanxi Province, P. R. China. Tel: 029-82312651.Responsible editor: Chai Ruihal 展开更多
关键词 Root diameter classes Variance analysis Root extinction coefficient Vertical distribution characters Site conditions Loess Plateau
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An Analysis of the Female Characters in E.M.Forster’s Novels
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作者 Dongyan Jiang 《Journal of Contemporary Educational Research》 2020年第7期101-106,共6页
This paper analyses the female characters in E.M.Forster’s novels from the perspective of feminism,through the deep exploration of E.M.Forster’s works,it is evident to draw a conclusion that there are four kinds of ... This paper analyses the female characters in E.M.Forster’s novels from the perspective of feminism,through the deep exploration of E.M.Forster’s works,it is evident to draw a conclusion that there are four kinds of female characters:first of all,stubborn and arrogant old ladies;the second type is insensitive but self-awakening middle-aged ladies;the third type is knowledgeable and smart young ladies;the last one is the warm-hearted and benevolent lady.These four kinds of different female characters can reveal that E.M.Forster has a contradictory attitude towards women.For one thing,he respected and sympathized with women,for another he discriminated against women. 展开更多
关键词 E.M.Forster Female characters analysis
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A SIMPLE ANALYSIS OF THE GEOTECTONICEVOLUTIONAL CHARACTERS OF TONGLINAREA,ANHUI
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作者 SHAO Yong-jun,PENG Sheng-lin,LIU Liang-ming (Departmentof Geology,Central South University,Changsha410 0 83,China) 《Geotectonica et Metallogenia》 2001年第1期76-78,共3页
Tonglin area is one ofthe areaswherethere existmany copperore deposits.The geotec- tonic property has many titles.Mostof geological scholarscall itthe lower Yangtze platform depression and divide the geotectonic stage... Tonglin area is one ofthe areaswherethere existmany copperore deposits.The geotec- tonic property has many titles.Mostof geological scholarscall itthe lower Yangtze platform depression and divide the geotectonic stages into formation of basement,sedimentaion of coverand intreplate deformation.According to the diwa theory,this paperclassifies itas the Jiangsu- Hubei geodepressional system ofthe Central China geodepressional region.Accord- ing to the analysis of the features ofstructural layers,the geotectonic evolution of the region is divided into four stages:pre- geosyncline,geosyncline,platform and 展开更多
关键词 ROCK A SIMPLE analysis of the GEOTECTONICEVOLUTIONAL characters of TONGLINAREA ANHUI
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Deep learning-based lung sound analysis for intelligent stethoscope
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作者 Dong-Min Huang Jia Huang +3 位作者 Kun Qiao Nan-Shan Zhong Hong-Zhou Lu Wen-Jin Wang 《Military Medical Research》 SCIE CAS CSCD 2024年第4期567-588,共22页
Auscultation is crucial for the diagnosis of respiratory system diseases.However,traditional stethoscopes have inherent limitations,such as inter-listener variability and subjectivity,and they cannot record respirator... Auscultation is crucial for the diagnosis of respiratory system diseases.However,traditional stethoscopes have inherent limitations,such as inter-listener variability and subjectivity,and they cannot record respiratory sounds for offline/retrospective diagnosis or remote prescriptions in telemedicine.The emergence of digital stethoscopes has overcome these limitations by allowing physicians to store and share respiratory sounds for consultation and education.On this basis,machine learning,particularly deep learning,enables the fully-automatic analysis of lung sounds that may pave the way for intelligent stethoscopes.This review thus aims to provide a comprehensive overview of deep learning algorithms used for lung sound analysis to emphasize the significance of artificial intelligence(AI)in this field.We focus on each component of deep learning-based lung sound analysis systems,including the task categories,public datasets,denoising methods,and,most importantly,existing deep learning methods,i.e.,the state-of-the-art approaches to convert lung sounds into two-dimensional(2D)spectrograms and use convolutional neural networks for the end-to-end recognition of respiratory diseases or abnormal lung sounds.Additionally,this review highlights current challenges in this field,including the variety of devices,noise sensitivity,and poor interpretability of deep models.To address the poor reproducibility and variety of deep learning in this field,this review also provides a scalable and flexible open-source framework that aims to standardize the algorithmic workflow and provide a solid basis for replication and future extension:https://github.com/contactless-healthcare/Deep-Learning-for-Lung-Sound-Analysis. 展开更多
关键词 Deep learning Lung sound analysis Respiratory sounds
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Flower morphology of Allium(Amaryllidaceae)and its systematic significance
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作者 Ju Eun Jang Shukherdorj Baasanmunkh +5 位作者 Nudkhuu Nyamgerel Seung-Yoon Oh Jun-Ho Song Ziyoviddin Yusupov Komijlon Tojibaev Hyeok Jae Choi 《Plant Diversity》 SCIE CAS CSCD 2024年第1期3-27,共25页
Allium is a complicated genus that includes approximately 1000 species.Although its morphology is well studied,the taxonomic importance of many morphological traits,including floral traits,are poorly understood.Here,w... Allium is a complicated genus that includes approximately 1000 species.Although its morphology is well studied,the taxonomic importance of many morphological traits,including floral traits,are poorly understood.Here,we examined and measured the floral characteristics of 87 accessions of 74 Allium taxa(belonging to 30 sections and nine subgenera)from Central to Eastern Asian countries.We then examined the taxonomic relationships between select flower characteristics and a phylogenetic tree based on ITS sequences.Our results confirm that floral morphology provides key taxonomic information to assess species delimitation in Allium.We found that perianth color is an important characteristic within the subg.Melanocrommyum,Polyprason,and Reticulatobulbosa.In subg.Allium,Cepa,and Rhizirideum,significant characteristics include ovary shape,perianth shape,and inner tepal apex.For species in subg.Angunium,the key taxonomic character is ovule number(only one ovule in per locule).In the subg.Allium,Cepa,Polyprason,and Reticulatobulbosa,which belong to the third evolutionary line of Allium,hood-like appendages occur in the ovary,although these do not occur in subg.Rhizirideum.Our results also indicated that the flower morphology of several species in some sections are not clearly distinguished,e.g.,sect.Sacculiferum(subg.Cepa)and sect.Tenuissima(subg.Rhizirideum).This study provides detailed photographs and descriptions of floral characteristics and information on general distributions,habitats,and phenology of the studied taxa. 展开更多
关键词 ALLIUM Flower morphology Pistil character Statistical analysis Significant characteristic Species level
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Canonical Correlation Analysis of Agronomic Characters of Brassica juncea in Western China
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作者 大次卓嘎 王建林 +1 位作者 次仁央金 王忠红 《Agricultural Science & Technology》 CAS 2011年第11期1600-1604,1666,共6页
[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 ... [Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character (containing 18 variables) were verified, including yield characters (5 variables), caulis characters (6 variables), branch characters (3 variables) and pod characters (3 variables). [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits. 展开更多
关键词 Western China Brassica juncea Ecological character Canonical correlation analysis Comparative study
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Analysis of Father and Daughter in Absalom, Absalom!
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作者 曲爽 《海外英语》 2016年第11期202-203,208,共3页
William Faulkner is a world-famous American novelist. Absalom, Absalom! is a story which happened in the southern United States, and it tells a family's experience of rising and falling from 1860 to 1910. Faulkner... William Faulkner is a world-famous American novelist. Absalom, Absalom! is a story which happened in the southern United States, and it tells a family's experience of rising and falling from 1860 to 1910. Faulkner gave a very vivid depiction and description of the characters to profoundly show the conflict between people and people, and the conflict between people and their inner world, touching the universal problems which are related to the condition of human beings. Through Sutpen, the representative of the old South, Faulkner showed his attitudes towards the old South, the racism. In his eyes, the old South was destined to fail and to decay because of the evil and rotten racism and tradition of this land. While through Judith, the daughter of Sutpen, Faulkner made the readers see the hope and future of a new world, the new South after civil war. 展开更多
关键词 FAULKNER analysis CHARACTER
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Preliminary Study on Quality Analysis of Yao Medicine Pileostegia tomentella Hand.-Mazz.
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作者 Xiaodong HUANG Xiumei MA +5 位作者 Yong TAN Jiangcun WEI Wen ZHONG Bing QING Qingmei DENG Hong LEI 《Medicinal Plant》 2023年第6期39-42,共4页
[Objectives]To establish a method for quality analysis of Medicine Pileostegia tomentella Hand.-Mazz.[Methods]According to the testing method of Chinese Pharmacopoeia(2020 Edition),the water content,total ash and alco... [Objectives]To establish a method for quality analysis of Medicine Pileostegia tomentella Hand.-Mazz.[Methods]According to the testing method of Chinese Pharmacopoeia(2020 Edition),the water content,total ash and alcohol-soluble extract of P.tomentella Hand.-Mazz.were determined.[Results]10 batches of P.tomentella Hand.-Mazz.from different habitats and in different collection time in Guangxi all had the same plant morphology and medicinal properties.The experimental results showed that the water content was 7.92%-10.35%,the total ash content was 5.53%-6.62%,the acid-insoluble ash content was 0.59%-0.76%,and the extract content was 11.63%-16.12%.[Conclusions]The identification method in this study can be used for the quality analysis of P.tomentella Hand.-Mazz.,and the experimental results can provide a scientific basis for the development and utilization of P.tomentella Hand.-Mazz.and the establishment of its quality standard. 展开更多
关键词 Pileostegia tomentella Hand.-Mazz Character identification Quality analysis
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Characteristics analyzing and parametric modeling of the arc sound in CO_2 GMAW for on-line quality monitoring 被引量:8
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作者 马跃洲 马文斌 +1 位作者 瞿敏 陈剑虹 《China Welding》 EI CAS 2006年第2期6-13,共8页
For on-line monitoring of welding quality, the characteristics of the arc sound signals in short circuit CO2 GMAW were analyzed in the time and frequency domains. The arc sound presents a series of ringing-like oscill... For on-line monitoring of welding quality, the characteristics of the arc sound signals in short circuit CO2 GMAW were analyzed in the time and frequency domains. The arc sound presents a series of ringing-like oscillations that occur at the end of short circuit i. e. the moment of arc re-ignition, and distributes mainly in the frequency band below 10 kHz. A concept of the arc tone channel and its equivalent electrical model were suggested, which is considered a time-dependent distributed parametric system of which the transmission properties depend upon the geometric and physical characteristics of the arc and surroundings, and is excited by the sound source results from the change of arc energy so that results in arc sound. The linear prediction coding ( LPC ) model is an estimation of the tone channel. The radial basis function ( RBF ) neural networks were built for on-line pattern recognition of the gas-lack in welding, in which the input vectors were formed with the LPC coefficients. The test results proved that the LPC model of arc sound and the RBF networks are feasible in on-line quality monitoring. 展开更多
关键词 arc sound signal analysis LPC model RBF neural network GMAW quality monitoring
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ANALYSISES OF GENE EFFECTS ON SOME COCOON CHARACTERS IN SILKWORM MORIL 被引量:2
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作者 Duan Jialong Zhu Jun (Anhui Agricultulal University,Hefei 230061,Anhui)(Zhejia Agricultural Uuiversity,Hangzhou 310029,Zhejiang) 《生物数学学报》 CSCD 北大核心 1994年第4期10-17,共8页
1.Estimates of genetic variance and covariance for individual characters showed that cocoon weight was controlled by both gene direct effect and maternal effect;Cocoon shell weight was controlled by gene direct effect... 1.Estimates of genetic variance and covariance for individual characters showed that cocoon weight was controlled by both gene direct effect and maternal effect;Cocoon shell weight was controlled by gene direct effect mainly;Cocoon shell ratio was mainly due to maternal effect and se x-linked effect.2.Estimates of genetic covariance components of each pair of ch aracters indicated that there were high significant positive relationships among most of genetic effects except maternal additive effect in cocoon weight and cocoon shell weight.There was a high positive relationship idirect effect between cocoon weight and cocoon shell ratio,but in cytop lasm effect and maternal effect were high negative relationships between them.Also there were high positive relationships in direct effect and maternal dominance between cocoon shell weight and cocoon shell ratio.3.Predictions of gene effects pointed out that sex-chromosome effects (Σi8=1Lii) on cocoon weight and cocoon shell weight both were lar ger positive values,that means cocoon weight and cocoon shell weight of females are generally higher than those of males in Silkworm. Standardized donmiance directions of direct effects on cocoon weight and cocoon shell weight were high positive values,but standardized domiance directieon of maternal effects on both of them were high negative values,it showed the two characters had larger heterosis in F1 generation and depressed in F2 generation.Sex-chromosome effect (Σi8=1Lii) on cocoon she11 ratio was high negative value,explaining that females usually have lower cocoon shell ratio than males.Standardized domiance directions of direct effect and maternal effect on cocoon shell ratio were not significant,predicting that the heterosis of cocoon shell ratio in F1 generation is not obvious comparing to cocoon weight and cocoon shell weight. 展开更多
关键词 SILKWORM COCOON characters Genetical analysis
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Analysis of the Climate Features and Changes of Heavy Fog in Wusu City 被引量:3
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作者 李彦杰 马琳 +1 位作者 闫勇 白学甫 《Meteorological and Environmental Research》 CAS 2010年第8期46-48,共3页
Based on the measured data of heavy fog in Wusu County during 1954-2009,its temporal and spatial distribution characteristics were analyzed.The results showed that heavy fog in Wusu mainly happened from later autumn t... Based on the measured data of heavy fog in Wusu County during 1954-2009,its temporal and spatial distribution characteristics were analyzed.The results showed that heavy fog in Wusu mainly happened from later autumn to beginning of the next spring.The most was in December,the least was in January.It had significant regional features and seasonal distribution characteristics.However,the days of heavy fog was irregular,but it was accordant with the decrease trend of frog days in recent years in China,while it was not significant.The situations of high-altitude uniform pressure field and the surface pressure field had a direct relationship with the formation of heavy fog. 展开更多
关键词 Heavy fog Climate character Changes analysis China
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Prediction of Intraoperative Fracture by Hammering Sound Frequency Analysis and Stress Estimation during Total Hip Arthroplasty 被引量:4
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作者 Rina Sakai Takeaki Yamamoto +4 位作者 Katsufumi Uchiyama Kensuke Fukushima Naonobu Takahira Kazuhiro Yoshida Masanobu Ujihira 《Journal of Biomedical Science and Engineering》 2020年第6期113-119,共7页
When a stem is inserted into the femur during total hip arthroplasty, sufficient fixation depends on the surgeon’s experience. An objective method of evaluating whether the stem has been correctly fixed may aid clini... When a stem is inserted into the femur during total hip arthroplasty, sufficient fixation depends on the surgeon’s experience. An objective method of evaluating whether the stem has been correctly fixed may aid clinicians in their decision. We examined the relationship between the sound frequency caused by hammering the stem and the internal stress in artificial femurs, and evaluated the utility of sound frequency analysis to prevent intraoperative fracture. Surgeons inserted one of two types of cementless stems (SL-PLUS and modified CLS) using routine operational procedures into 13 artificial femurs. These are the standard Zweymüllers used in Europe. The difference is the lateral shape;SL-PLUS has holes for removal and the modified CLS has fins to prevent rotation. We estimated stress in the femur via finite element analysis, measured the hammering force, and recorded the sound of hammering for frequency analysis. Finite element analysis revealed that the hammering sound frequency decreased as the maximum stress increased. A decrease in frequency suggested that fixation was sufficient and that continued hammering would increase the risk of fracture. Thus, evaluation of the change in sound frequency during stem insertion may indicate when the hammering force should be reduced, thereby preventing intraoperative periprosthetic fractures. Further frequency change may also predict fractures prior to visual confirmation. We concluded that sound frequency analysis has potential as an objective evaluation method to help prevent intraoperative periprosthetic fractures during stem insertion. 展开更多
关键词 Periprosthetic Fracture Total Hip Arthroplasty Hammering sound Frequency analysis
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Spectral analysis of bowel sounds in intestinal obstruction using an electronic stethoscope 被引量:14
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作者 Siok Siong Ching Yih Kai Tan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第33期4585-4592,共8页
AIM: To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. METHODS: Subjects were patients who presented with a diagnosis of possibl... AIM: To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. METHODS: Subjects were patients who presented with a diagnosis of possible intestinal obstruction based on symptoms, signs, and radiological findings. A 3MTH Littmann Model 4100 electronic stethoscope was used in this study. With the patients lying supine, six 8-second recordings of bowel sounds were taken from each patient from the lower abdomen. The recordings were analysed for sound duration, soundto-sound interval, dominant frequency, and peak frequency. Clinical and radiological data were reviewed and the patients were classified as having either acute, subacute, or no bowel obstruction. Comparison of bowel sound characteristics was made between these subgroups of patients. In the presence of an obstruction, the site of obstruction was identified and bowel calibre was also measured to correlate with bowel sounds. RESULTS: A total of 71 patients were studied during the period July 2009 to January 2011. Forty patientshad acute bowel obstruction (27 small bowel obstruction and 13 large bowel obstruction), 11 had subacute bowel obstruction (eight in the small bowel and three in large bowel) and 20 had no bowel obstruction (diagnoses of other conditions were made). Twenty-five patients received surgical intervention (35.2%) during the same admission for acute abdominal conditions. A total of 426 recordings were made and 420 recordings were used for analysis. There was no significant difference in sound-to-sound interval, dominant frequency, and peak frequency among patients with acute bowel obstruction, subacute bowel obstruction, and no bowel obstruction. In acute large bowel obstruction, the sound duration was significantly longer (median 0.81 s vs 0.55 s, P = 0.021) and the dominant frequency was significantly higher (median 440 Hz vs 288 Hz, P = 0.003) when compared to acute small bowel obstruction. No significant difference was seen between acute large bowel obstruction and large bowel pseudoobstruction. For patients with small bowel obstruction, the sound-to-sound interval was significantly longer in those who subsequently underwent surgery compared with those treated non-operatively (median 1.29 s vs 0.63 s, P < 0.001). There was no correlation between bowel calibre and bowel sound characteristics in both acute small bowel obstruction and acute large bowel obstruction. CONCLUSION: Auscultation of bowel sounds is nonspecific for diagnosing bowel obstruction. Differences in sound characteristics between large bowel and small bowel obstruction may help determine the likely site of obstruction. 展开更多
关键词 Bowel sounds Intestinal obstruction Spectral analysis Electronic stethoscope
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