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Real-Time PCR Technique and Its Application in Quantification of Plant Nucleic Acid Molecules 被引量:8
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作者 刘进元 《Acta Botanica Sinica》 CSCD 2003年第6期631-637,共7页
Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of ini... Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of initial template copy numbers as PCR products are generated. This technique significantly simplifies and accelerates the process of producing reproducible quantification of nucleic acid molecules. It not only is a sensitive, accurate and rapid quantitative method, but it also provides an easier way to calculate the absolute starting copy number of nucleic acid molecules to be tested. Together with molecular bio-techniques, like microarray, real-time PCR will play a very important role in many aspects of molecular life science such as functional gene analysis and disease molecular diagnostics. This review introduces the detailed principles and application of the real-time PCR technique, describes a recently developed system for exact quantification of AUX/IAA genes In Arabidopsis, and discusses the problems with the real-time PCR process. 展开更多
关键词 real-time PCR technique quantification of plant nucleic acid molecules gene expression molecular medicine
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Effectiveness of hybrid ensemble machine learning models for landslide susceptibility analysis:Evidence from Shimla district of North-west Indian Himalayan region
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作者 SHARMA Aastha SAJJAD Haroon +2 位作者 RAHAMAN Md Hibjur SAHA Tamal Kanti BHUYAN Nirsobha 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2368-2393,共26页
The Indian Himalayan region is frequently experiencing climate change-induced landslides.Thus,landslide susceptibility assessment assumes greater significance for lessening the impact of a landslide hazard.This paper ... The Indian Himalayan region is frequently experiencing climate change-induced landslides.Thus,landslide susceptibility assessment assumes greater significance for lessening the impact of a landslide hazard.This paper makes an attempt to assess landslide susceptibility in Shimla district of the northwest Indian Himalayan region.It examined the effectiveness of random forest(RF),multilayer perceptron(MLP),sequential minimal optimization regression(SMOreg)and bagging ensemble(B-RF,BSMOreg,B-MLP)models.A landslide inventory map comprising 1052 locations of past landslide occurrences was classified into training(70%)and testing(30%)datasets.The site-specific influencing factors were selected by employing a multicollinearity test.The relationship between past landslide occurrences and influencing factors was established using the frequency ratio method.The effectiveness of machine learning models was verified through performance assessors.The landslide susceptibility maps were validated by the area under the receiver operating characteristic curves(ROC-AUC),accuracy,precision,recall and F1-score.The key performance metrics and map validation demonstrated that the BRF model(correlation coefficient:0.988,mean absolute error:0.010,root mean square error:0.058,relative absolute error:2.964,ROC-AUC:0.947,accuracy:0.778,precision:0.819,recall:0.917 and F-1 score:0.865)outperformed the single classifiers and other bagging ensemble models for landslide susceptibility.The results show that the largest area was found under the very high susceptibility zone(33.87%),followed by the low(27.30%),high(20.68%)and moderate(18.16%)susceptibility zones.The factors,namely average annual rainfall,slope,lithology,soil texture and earthquake magnitude have been identified as the influencing factors for very high landslide susceptibility.Soil texture,lineament density and elevation have been attributed to high and moderate susceptibility.Thus,the study calls for devising suitable landslide mitigation measures in the study area.Structural measures,an immediate response system,community participation and coordination among stakeholders may help lessen the detrimental impact of landslides.The findings from this study could aid decision-makers in mitigating future catastrophes and devising suitable strategies in other geographical regions with similar geological characteristics. 展开更多
关键词 Landslide susceptibility Site-specific factors Machine learning models Hybrid ensemble learning Geospatial techniques Himalayan region
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Cultivation Techniques of Beibei Type of Pumpkin in Spring Greenhouse of Beijing Region
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作者 Ying ZHANG Chao MA +3 位作者 Jianbo ZENG Yanli CHEN Ting LI Xuesong YOU 《Meteorological and Environmental Research》 CAS 2021年第1期87-89,共3页
Beibei pumpkin has the characteristics of early maturity,high yield,strong disease resistance,cold resistance,strong ability of continuous fruiting,excellent quality and easy cultivation,and its cultivation in spring ... Beibei pumpkin has the characteristics of early maturity,high yield,strong disease resistance,cold resistance,strong ability of continuous fruiting,excellent quality and easy cultivation,and its cultivation in spring greenhouse of Beijing region could effectively improve yield and commodity.In this paper,cultivation techniques of Beibei pumpkin in spring greenhouse are introduced,including cultivation of strong seedlings,planting,management after planting and storage after harvest. 展开更多
关键词 Beibei pumpkin Beijing region Spring greenhouse Cultivation techniques
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Two-point Dixon and six-point Dixon magnetic resonance techniques in the detection,quantification and grading of hepatic steatosis
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作者 Mohamed Elfaal Alanna Supersad +6 位作者 Craig Ferguson Stephanie Locas Florin Manolea Mitchell P Wilson Medica Sam Wendy Tu Gavin Low 《World Journal of Radiology》 2023年第10期293-303,共11页
BACKGROUND Hepatic steatosis is a very common problem worldwide.AIM To assess the performance of two-and six-point Dixon magnetic resonance(MR)techniques in the detection,quantification and grading of hepatic steatosi... BACKGROUND Hepatic steatosis is a very common problem worldwide.AIM To assess the performance of two-and six-point Dixon magnetic resonance(MR)techniques in the detection,quantification and grading of hepatic steatosis.METHODS A single-center retrospective study was performed in 62 patients with suspected parenchymal liver disease.MR sequences included two-point Dixon,six-point Dixon,MR spectroscopy(MRS)and MR elastography.Fat fraction(FF)estimates on the Dixon techniques were compared to the MRS-proton density FF(PDFF).Statistical tests used included Pearson’s correlation and receiver operating characteristic.RESULTS FF estimates on the Dixon techniques showed excellent correlation(≥0.95)with MRS-PDFF,and excellent accuracy[area under the receiver operating characteristic(AUROC)≥0.95]in:(1)Detecting steatosis;and(2)Grading severe steatosis,(P<0.001).In iron overload,two-point Dixon was not evaluable due to confounding T2*effects.FF estimates on six-point Dixon vs MRS-PDFF showed a moderate correlation(0.82)in iron overload vs an excellent correlation(0.97)without iron overload,(P<0.03).The accuracy of six-point Dixon in grading mild steatosis improved(AUROC:0.59 to 0.99)when iron overload cases were excluded.The excellent correlation(>0.9)between the Dixon techniques vs MRSPDFF did not change in the presence of liver fibrosis(P<0.01).CONCLUSION Dixon techniques performed satisfactorily for the evaluation of hepatic steatosis but with exceptions. 展开更多
关键词 Chemical shift encoded Dixon magnetic resonance techniques Hepatic steatosis Liver fat quantification Magnetic resonance spectroscopy Proton density fat fraction ULTRASOUND
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Impact of Spectral Nudging on the Downscaling of Tropical Cyclones in Regional Climate Simulations 被引量:5
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作者 Suk-Jin CHOI Dong-Kyou LEE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第6期730-742,共13页
This study investigated the simulations of three months of seasonal tropical cyclone (TC) activity over the western North Pacific using the Advanced Research WRF Model. In the control experiment (CTL), the TC freq... This study investigated the simulations of three months of seasonal tropical cyclone (TC) activity over the western North Pacific using the Advanced Research WRF Model. In the control experiment (CTL), the TC frequency was considerably overestimated. Additionally, the tracks of some TCs tended to have larger radii of curvature and were shifted eastward. The large-scale environments of westerly monsoon flows and subtropical Pacific highs were unreasonably simulated. The overestimated frequency of TC formation was attributed to a strengthened westerly wind field in the southern quadrants of the TC center. In comparison with the experiment with the spectral nudging method, the strengthened wind speed was mainly modulated by large-scale flow that was greater than approximately 1000 km in the model domain. The spurious formation and undesirable tracks of TCs in the CTL were considerably improved by reproducing realistic large-scale atmospheric monsoon circulation with substantial adjustment between large-scale flow in the model domain and large-scale boundary forcing modified by the spectral nudging method. The realistic monsoon circulation took a vital role in simulating realistic TCs. It revealed that, in the downscaling from large-scale fields for regional climate simulations, scale interaction between model-generated regional features and forced large-scale fields should be considered, and spectral nudging is a desirable method in the downscaling method. 展开更多
关键词 tropical cyclone spectral nudging technique dynamic downscaling regional climate simulation
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Using side-dressing technique to reduce nitrogen leaching and improve nitrogen recovery efficiency under an irrigated rice system in the upper reaches of Yellow River Basin, Northwest China 被引量:5
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作者 ZHANG Ai-ping GAO Ji +4 位作者 LIU Ru-liang ZHANG Qing-wen CHEN Zhe YANG Shi-qi YANG Zheng-li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期220-231,共12页
The excessive nitrogen (N) fertilizer input coupled with flood irrigation might result in higher N leaching and lower nitrogen recovery efficiency (NRE). Under an intensive rice system in the Ningxia irrigation re... The excessive nitrogen (N) fertilizer input coupled with flood irrigation might result in higher N leaching and lower nitrogen recovery efficiency (NRE). Under an intensive rice system in the Ningxia irrigation region, China, environmental friendly N management practices are hreavily needed to balance the amount of N input for optimum crop production while minimize the nitrogen loss. The objective of this study was to determine the influences of side-dressing (SD) technique in mechanical transplanting systems on the NRE, N leaching losses and rice yield in anthropogenic-alluvial soil during two rice growing seasons (2010-2011). Four fertilizer N treatments were established, including conventional urea rate (CU, 300 kg ha-1 yr-1); higher SD of controlled-release N fertilizer rate (SD1,176 kg ha-1 yr-1); lower SD of controlled-release N fertilizer rate (SD2, 125 kg ha-1 yr-1); and control (CK, no N fertilizer). Field lysimeters were used to quantify drainage from undisturbed soil during six rice growing stages. Meanwhile, the temporal variations of total nitrigen (TN), NO3--N, and NH4+-N concentrations in percolation water were examined. The results showed that SD1 substantially improved NRE and reduced N leaching losses while maintaining rice yields. Across two years, the averaged NRE under SD1 treatment increased by 25.5% as relative to CU, but yet the rice yield was similar between two treatments. On average, the nitrogen loss defined as TN, NH4+-N, and NO3--N under the SD1 treatment reduced by 27.4, 37.2 and 24.1%, respectively, when compared with CU during the study periods. Although the SD2 treatment could further reduce N leaching loss to some extent, this technique would sharply decline rice yield, with the magnitude of as high as 21.0% relative to CU treatment. Additionally, the average NRE under SD2 was 11.2% lower than that under SD1 treatment. Overall, the present study concluded that the SO technique is an effective strategy to reduce N leaching and increase NRE, thus potentially mitigate local environmental threat. We propose SD1 as a novel alternative fertilizer technique under an irrigated rice-based system in Ningxia irrigation region when higher yields are under consideration. 展开更多
关键词 side-dressing technique nitrogen recovery efficiency nitrogen leaching loss Ningxia irrigation region anthropogenic-alluvial soil
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Numerical simulation of protection range in exploiting the upper protective layer with a bow pseudo-incline technique 被引量:15
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作者 HU Guo-zhong WANG Hong-tu LI Xiao-hong FAN Xiao-gang YUAN Zhi-gang 《Mining Science and Technology》 EI CAS 2009年第1期58-64,共7页
The developing processes of stress and deformation fields of a protected layer after mining an upper-protective layer with a bow pseudo-incline technique were simulated to locate the protection region. The pressure re... The developing processes of stress and deformation fields of a protected layer after mining an upper-protective layer with a bow pseudo-incline technique were simulated to locate the protection region. The pressure relief of the protected layer was analyzed after mining the upper-protective layer. The pressure relief angle along the strike and incline were located according to the roles of protection of the deformation and stress pressure-relief of the protective layer after mining. This results show that the upper-protective layer with the bow pseudo-incline technique have an upper and downside pressure relief angle of 85 and 68 degrees respectively; the distribution of strike pressure relief angles along the pseudo-incline working face is uneven and their values range from 38.3 to 51 degrees. The pressure relief angle of the inclined middle location was the largest. The distribution of the protection region of the upper-protective layer with the bow pseudo-incline teelmique located by practical tests and numerical simulation is essentially consistent, compared with the results obtained by these methods. 展开更多
关键词 bow pseudo-incline technique upper-protective layer protection region 3D numerical simulation
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Demand Flexibility of Residential Buildings:Definitions,Flexible Loads,and Quantification Methods 被引量:4
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作者 Zhengyi Luo Jinqing Peng +4 位作者 Jingyu Cao Rongxin Yin Bin Zou Yutong Tan Jinyue Yan 《Engineering》 SCIE EI CAS 2022年第9期123-140,共18页
This paper reviews recent research on the demand flexibility of residential buildings in regard to definitions,flexible loads,and quantification methods.A systematic distinction of the terminology is made,including th... This paper reviews recent research on the demand flexibility of residential buildings in regard to definitions,flexible loads,and quantification methods.A systematic distinction of the terminology is made,including the demand flexibility,operation flexibility,and energy flexibility of buildings.A comprehensive definition of building demand flexibility is proposed based on an analysis of the existing definitions.Moreover,the flexibility capabilities and operation characteristics of the main residential flexible loads are summarized and compared.Models and evaluation indicators to quantify the flexibility of these flexible loads are reviewed and summarized.Current research gaps and challenges are identified and analyzed as well.The results indicate that previous studies have focused on the flexibility of central air conditioning,electric water heaters,wet appliances,refrigerators,and lighting,where the proportion of studies focusing on each of these subjects is 36.7%,25.7%,14.7%,9.2%,and 8.3%,respectively.These flexible loads are different in running modes,usage frequencies,seasons,and capabilities for shedding,shifting,and modulation,while their response characteristics are not yet clear.Furthermore,recommendations are given for the application of white-,black-,and grey-box models for modeling flexible loads in different situations.Numerous static flexibility evaluation indicators that are based on the aspects of power,temporality,energy,efficiency,economics,and the environment have been proposed in previous publications,but a consensus and standardized evaluation framework is lacking.This review can help readers better understand building demand flexibility and learn about the characteristics of different residential flexible loads,while also providing suggestions for future research on the modeling techniques and evaluation metrics of residential building demand flexibility. 展开更多
关键词 Residential building Demand flexibility Flexible loads Modeling techniques quantification indicators
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Developing Lexicons for Enhanced Sentiment Analysis in Software Engineering:An Innovative Multilingual Approach for Social Media Reviews
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作者 Zohaib Ahmad Khan Yuanqing Xia +4 位作者 Ahmed Khan Muhammad Sadiq Mahmood Alam Fuad AAwwad Emad A.A.Ismail 《Computers, Materials & Continua》 SCIE EI 2024年第5期2771-2793,共23页
Sentiment analysis is becoming increasingly important in today’s digital age, with social media being a significantsource of user-generated content. The development of sentiment lexicons that can support languages ot... Sentiment analysis is becoming increasingly important in today’s digital age, with social media being a significantsource of user-generated content. The development of sentiment lexicons that can support languages other thanEnglish is a challenging task, especially for analyzing sentiment analysis in social media reviews. Most existingsentiment analysis systems focus on English, leaving a significant research gap in other languages due to limitedresources and tools. This research aims to address this gap by building a sentiment lexicon for local languages,which is then used with a machine learning algorithm for efficient sentiment analysis. In the first step, a lexiconis developed that includes five languages: Urdu, Roman Urdu, Pashto, Roman Pashto, and English. The sentimentscores from SentiWordNet are associated with each word in the lexicon to produce an effective sentiment score. Inthe second step, a naive Bayesian algorithm is applied to the developed lexicon for efficient sentiment analysis ofRoman Pashto. Both the sentiment lexicon and sentiment analysis steps were evaluated using information retrievalmetrics, with an accuracy score of 0.89 for the sentiment lexicon and 0.83 for the sentiment analysis. The resultsshowcase the potential for improving software engineering tasks related to user feedback analysis and productdevelopment. 展开更多
关键词 Emotional assessment regional dialects SentiWordNet naive bayesian technique lexicons software engineering user feedback
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Sap-flow measurement and scale transferring from sample trees to entire forest stand of Populus euphratica in desert riparian forest in extreme arid region 被引量:2
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作者 JianHua Si 1, Qi Feng 1, HaiYang Xi 1, ZongQiang Chang 1, YongHong Su 1, Kai Zhang 1,2 1. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China. 2. Institute of Arid Meteorology, China Meteorological Administration, Lanzhou, Gansu 730020, China. 《Research in Cold and Arid Regions》 2009年第3期258-266,共9页
Understanding how the transpiration of this vegetation type responds to environmental stress is important for determining the wa-ter-balance dynamics of the riparian ecosystem threatened by groundwater depletion. Tran... Understanding how the transpiration of this vegetation type responds to environmental stress is important for determining the wa-ter-balance dynamics of the riparian ecosystem threatened by groundwater depletion. Transpiration and sap flow were measured using the heat-pulse technique. The results were then projected up to the stand level to investigate the stand’s water-use in relation to climate forcing in the desert riparian forest in an extreme arid region. This study took place from April through October 2003 and from May through October 2004. The experimental site was selected in the Populus euphratica Forest Reserve (101o10' E, 41o59' N) in Ejina county, in the lower Heihe River basin, China. The sapwood area was used as a scalar to extrapolate the stand-water consumption from the whole trees’ water consumption measured by the heat-pulse velocity recorder (HPVR). Scale transferring from a series of individual trees to a stand was done according to the existing natural variations between trees under given environmental conditions. The application of the biometric parameters available from individual tree and stand levels was proved suitable for this purpose. A significant correlation between the sapwood area and tree diameter at breast height (DBH) was found. The prediction model is well fitted by the power model. On the basis of the prediction model, the sapwood area can be cal-culated by DBH. The sap-flow density can then be used to extrapolate the stand-water use by means of a series of mathematical models. 展开更多
关键词 sap flow heat-pulse technique sapwood area scale transferring extreme arid region Populus euphratica
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Sand-fixing characteristics of Carex brunnescens and its application with straw checkerboard technique in restoration of degraded alpine meadows 被引量:4
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作者 KANG Jianjun ZHAO Ming +4 位作者 TAN Yanrong ZHU li BING Danhui ZHANG Yangdong TONG Shengli 《Journal of Arid Land》 SCIE CSCD 2017年第5期651-665,共15页
Carex brunnescens(Pers.), a typical clonal species, is considered to be the only herb found to date that can develop on sand dunes in Maqu alpine region of northwestern China. However, the characteristics that C. br... Carex brunnescens(Pers.), a typical clonal species, is considered to be the only herb found to date that can develop on sand dunes in Maqu alpine region of northwestern China. However, the characteristics that C. brunnescens resists to harsh alpine environment have not been documented. In this study, we conducted a field investigation to determine the morphological, reproductive, and sand-fixing characteristics of C. brunnescens. Concomitantly, we transplanted the belowground rhizomes of C. brunnescens to sand dunes and compared the abilities to restore degraded alpine meadows among sand dunes that had no further treatment(SD+N), sand dunes that had straw checkerboard technique but no transplanted rhizomes of C. brunnescens(SD+SCT), and sand dunes that had both SCT and transplanted rhizomes of C. brunnescens(SD+SCT+P). We found that belowground vertical rhizomes and horizontal rhizomes(including branching rhizomes and main rhizomes) of C. brunnescens were highly developed and that population reproduction was dominated by horizontal rhizomes. C. brunnescens exhibited a significant sand-fixation effect under following conditions: population density was 145–156 ramets/m^2, vegetation cover was 31.2%–39.3%, total length of belowground rhizomes was 11,223 cm/m^2, total length of belowground first-order roots was 9161–10,524 cm/m^2, fresh weight of aboveground part was 198.5–212.6 g/m^2, and fresh weight of belowground part was 578.8–612.4 g/m^2. It should be particularly noted that SD+SCT+P treatment(sand dunes that had both straw checkerboard technique and transplanted rhizomes of C. brunnescens) was the best and SD+N(sand dunes that had no further treatment) was the worst in terms of following biotic indicators: total number of reproductive ramets, total number of belowground rhizomes, and fresh weight of aboveground and belowground parts of C. brunnescens, contents of soil organic carbon, available nitrogen, microbial biomass carbon, and microbial biomass nitrogen. It implies that applying SCT in sand dunes and transplanting belowground rhizomes to sand dunes with SCT could improve both soil fertility and growth of C. brunnescens. These results suggest that the SCT-promoted high reproductive abilities of belowground rhizomes of C. brunnescens can successfully facilitate the establishment of ramets and can thus be an effective strategy to restore degraded vegetation in Maqu alpine region of northwestern China. 展开更多
关键词 Carex brunnescens(Pers perennial herb sand-fixing straw checkerboard technique Maqu alpine region
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Distribution of Lg coda Q in Xinjiang and its adjacent regions
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作者 徐彦 毛燕 +2 位作者 胡家富 苏有锦 丛连理 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2005年第2期162-170,254,共10页
In this study, we collected 1156 broadband vertical components records at 22 digital seismic stations in Xinjiang region, Urumqi station, and 7 stations in the adjacent regions during the period of 1999-2003. The reco... In this study, we collected 1156 broadband vertical components records at 22 digital seismic stations in Xinjiang region, Urumqi station, and 7 stations in the adjacent regions during the period of 1999-2003. The records were firstly processed by the stacked spectral ratio method to obtain Q0 (Q at 1 Hz) and the frequency correlation factor η corresponding to each path. Based on the results, the distribution images of Q0 and η in 1°×1° grids for Xinjiang region were gained by the back-projection technique. The results indicate that Q0 is high (300-450) in the Tarim platform and marginal Siberian platform, while Q0 is low (150-250) in the southern regions as west Kunlun fold system and Songpan-Ganzi fold system. In the northern regions as Junggar fold system and Tianshan fold system, Q0 is also low (250-300) and η varies between 0.5 and 0.9. 展开更多
关键词 Lg coda Q stacked spectral ratio method back-projection technique Xinjiang region
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106 New Emission-line Galaxies and 29 New Galactic HⅡ Regions are Identified with Spectra in the Unknown Data Set of LAMOST DR7
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作者 Yan Lu A-Li Luo +9 位作者 Li-Li Wang You-Fen Wang Yin-Bi Li Jin-Shu Han Li Qin Yan-Ke Tang Bo Qiu Shuo Zhang Jian-Nan Zhang Yong-Heng Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第6期170-182,共13页
This work is to retrieve emission-line spectra from the“Unknown”data set in LAMOST DR7 V1.2,most of which are low signal-to-noise ratios spectra.In the work,we perform emission line search and redshift calculations ... This work is to retrieve emission-line spectra from the“Unknown”data set in LAMOST DR7 V1.2,most of which are low signal-to-noise ratios spectra.In the work,we perform emission line search and redshift calculations on the Unknown data set to get possible emission line galaxy spectra.Taking the galaxy spectra released by LAMOST as templates,the Product Quantization(PQ)based approximate nearest neighbor(ANN)search is used to retrieve the nearest neighbors of each spectrum.We keep the spectra for which the calculated redshift and the published redshift of the template meet the threshold,and 16,188 spectra with emission lines are obtained from the LAMOST DR7 Unknown data set.After visual inspection of spectra 10,266 spectra are left,in which 5828 spectra are identified as emission-line galaxies,1782 spectra show ionization nebula features,and other 2656 are not clearly classified.Among 5828 spectra,5720 can be found in Strasbourg astronomical Data Center catalog,Sloan Digital Sky Survey catalog,or NASA/IPAC Extragalactic Database catalog.The 108 spectra(corresponding to 106unique coordinates of R.A.and decl.)which have no record in these three databases are new discoveries;for the1782 spectra showing ionization nebula features,most of them have radial velocities less than 150 kilometers per second.We check them with the latest version of WISE HⅡcatalog V2.0(short for HIICat V2)and 985 out of the1782 spectra belong to 72 HⅡregions.Of these HⅡregions,43 were previously identified while the other 29 are newly identified in this work including 797 newly observed spectra.Besides,there are still 2656 spectra that cannot be clearly classified although they have obvious emission lines and with small redshift.Finally,106 new emissionline galaxies and 29 new Galactic HⅡregions are identified,and we conclude that the ANN method sped up by the PQ algorithm is efficient in solving the problem of pairing spectra with massive data set to figure out their classes.We present our result at the link http://paperdata.china-vo.org/LY_paper/Work2/press Work2_last.zip. 展开更多
关键词 techniques spectroscopic-Galaxies-(ISM:)HⅡregions
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A Two-Dimensional Mathematical Model to Analyze Thermal Variations in Skin and Subcutaneous Tissue Region of Human Limb during Surgical Wound Healing
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作者 Namrata Gupta Madhvi Shakya 《Applied Mathematics》 2016年第2期145-158,共14页
During wound healing, the metabolic activity associated with each phase must occur in the proper sequence, at a specific time, and continue for a specific duration at an optimal intensity. Any disturbance in appropria... During wound healing, the metabolic activity associated with each phase must occur in the proper sequence, at a specific time, and continue for a specific duration at an optimal intensity. Any disturbance in appropriate thermal environment may complicate the wound healing process and may give rise to wound infection. In the presented paper a transient state two-dimensional mathematical model has been developed to analyse thermal variations in skin and subcutaneous tissue (SST) region of human limb. Due to circular shape of human limb, model has been developed in polar coordinates. The domain of the study consists of two types of tissues: abnormal tissues and normal tissues. The post surgery peripheral tissue of human limb during healing time is considered as abnormal tissues. The effect of variable density of blood vessels in dermal layer of both tissues on the physical and physiological parameters is incorporated in the model. The effect of healing on physiological parameters of abnormal tissue is incorporated by considering the physiological parameters to be function of time “t”. The effect of different climatic conditions is considered in the model. Taking into account the variable core temperature due to anatomy of arteries and variable physiological parameters in dermal layer of peripheral region, the well known Pennes’ bio heat equation is used to analyse the time-dependent temperature distribution of both normal and abnormal tissues. Comparison between temperature profiles of both normal and abnormal tissue has been done using finite element approach with bilinear shape functions in polar coordinates. A computer program in MATLAB has been developed to simulate the results. 展开更多
关键词 Bio-Heat Equation Surgical Wound Healing Finite Element technique Crank-Nicolson Method Skin and Subcutaneous Tissue region
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Key Points of Simple Cultivation Technique for Whole-plant Silage Maize in Guangxi
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作者 Chenglin ZOU Kaijian HUANG 《Asian Agricultural Research》 2021年第2期47-49,共3页
With the vigorous development of animal husbandry in Guangxi,feed problems have become increasingly prominent.Silage maize has the characteristics of rapid growth,high nutritional value,easy digestion and absorption,a... With the vigorous development of animal husbandry in Guangxi,feed problems have become increasingly prominent.Silage maize has the characteristics of rapid growth,high nutritional value,easy digestion and absorption,and a large amount of biological output being obtained in a short time.It is one of the ideal basic feeds for cattle and sheep and other breeding industries.Based on this,the simple cultivation technique of whole-plant silage maize was summarized from the aspects of land preparation,selection of maize variety,sowing,field management,pest control and timely harvesting,so as to provide technical reference for scientific planting of silage maize in Guangxi. 展开更多
关键词 Whole-plant silage maize Cultivation technique Guangxi Zhuang Autonomous region
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Quantification and Determination of Starch in Diets Using Different Methodologies:Infrared Spectroscopy with Fourier Transformer,Laser Diffraction and Enzymatic Analysis
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作者 Andressa Nathalie Nunes Eloisa de Oliveira Simoes Saliba +6 位作者 Dalton Oliveira Fontes Ana Tereza Peret Dell’Isola Tatiana Carolina Gomes Dutra de Souza Poliana Campos Esmaile Perceu Rocha Nunes Jaqueline Simoes Saliba Ludhiana Rosa Ferreira 《American Journal of Analytical Chemistry》 2017年第2期151-157,共7页
A digestibility experiment was conducted in the Animal Nutrition Laboratory of the Veterinary School of the Federal University of Minas Gerais (UFMG), Protocol ethics committee for work with animal experimentation CET... A digestibility experiment was conducted in the Animal Nutrition Laboratory of the Veterinary School of the Federal University of Minas Gerais (UFMG), Protocol ethics committee for work with animal experimentation CETEA/ UFMG 212/2010, in order to validate the instrumental techniques Laser Diffraction (Partica) and Infrared Spectroscopy with Fourier Transformer (FTIR) method, as replacement methods of the reference (Enzymatic Analysis) Technique, of starch quantification in diets of growing pigs. The experiment lasted 12 days (7 days of adaptation to the cage and diet and 5 days of total collection). Fifteen barrows with average weight of ±25 kg and 65 days old were used for this study. A completely randomized experimental design was adopted, with split plots and subplots. The plots were the diets (1—Reference, 2—Reference + inclusion of 30% micronized soybean and 3—Reference +30% substitution of plasma) and the subplots were the techniques (Partica, FTIR and Enzymatic Technique, with five repetitions (animals) per diet). The results obtained with the Partica and FTIR techniques were compared to the reference method. There was no statistical difference (p > 5%) between these techniques evaluated in comparison to the reference method to quantify starch. However, it was observed that the FTIR technique was different from the reference method for (p > 5%) overestimating the means of evaluated samples. 展开更多
关键词 Instrumental techniques Enzymatic technique quantification of Starch
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一种基于SOFM神经网络的高光谱图像快速分类方法 被引量:3
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作者 谌德荣 陶鹏 +1 位作者 宫久路 范宁军 《兵工学报》 EI CAS CSCD 北大核心 2009年第2期165-169,共5页
高光谱图像的快速准确分类是遥感图像处理的关键技术之一。本文提出了区域特征光谱(RFS)的概念,并采用空间邻域聚类方法提取区域特征光谱;提出了以区域特征光谱作为SOFM神经网络输入的RFS-SOFM高光谱图像快速分类方法,该方法通过区域特... 高光谱图像的快速准确分类是遥感图像处理的关键技术之一。本文提出了区域特征光谱(RFS)的概念,并采用空间邻域聚类方法提取区域特征光谱;提出了以区域特征光谱作为SOFM神经网络输入的RFS-SOFM高光谱图像快速分类方法,该方法通过区域特征光谱代替单个像元光谱实现神经网络运算量的降低和对图像噪声的抑制。对AVIRIS图像数据的仿真结果表明:RFS-SOFM分类精度高于SOFM神经网络和K-均值算法,计算量约为K-均值的163.6%,SOFM神经网络的5.9%. 展开更多
关键词 摄影测量与遥感技术 高光谱图像 分类 SofM神经网络 区域特征光谱
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Parameters affecting different acoustic radiation force impulse applications in the diagnosis of fibrotic liver changes 被引量:5
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作者 Sabrina Galgenmueller Heike Jaeger +5 位作者 Wolfgang Kratzer Stefan A Schmidt Suemeyra Oeztuerk Mark M Haenle Richard A Mason Tilmann Graeter 《World Journal of Gastroenterology》 SCIE CAS 2015年第27期8425-8432,共8页
AIM: To analyze the virtual touch tissue quantification(VTTQ) and virtual touch imaging quantification(VTIQ) techniques, and identify possible factors that may influence VTTQ and VTIQ measurements.METHODS: One hundred... AIM: To analyze the virtual touch tissue quantification(VTTQ) and virtual touch imaging quantification(VTIQ) techniques, and identify possible factors that may influence VTTQ and VTIQ measurements.METHODS: One hundred and eighty-six(104 women/82 men) of 323 subjects met the inclusion criteria(age > 18 years, no history of chronic or gastrointestinal disease, body-mass index(BMI) < 30 kg/m2, a fasting period of at least three hours, no history of hepatotoxic pharmaceuticals, alcohol consumption < 24 g/d in men and < 12 g/d in women, and normal findings upon ultrasound examination of the abdomen). Measurements were taken at depths of 50 mm with VTTQ, 15 mm and 25 mm with VTIQ in the right hepatic lobe, and at 15 mm with only VTIQ in the left hepatic lobe. The examiner acquired six measurements per position, thereby giving 24 measurements in total.RESULTS: The 95% confidence intervals of mean were1.23-1.29 m/s for VTTQ and 1.29-1.37 m/s, 1.17-1.23 m/s, and 1.48-1.57 m/s for VTIQ in a depth of 15 mm and 25 mm in the right hepatic lobe and 15 mm in the left hepatic lobe. Only superficial measurements in the right hepatic lobe with the VTIQ method exhibited an effect of age on shear wave velocity. Measurements acquired using the 6C1 probe with the VTTQ method showed no dependence on BMI. By comparison, BMI influenced measurements taken with the VTIQ method using the 9L4 probe in the superficial and deep areas of the right hepatic lobe, as well as in the left hepatic lobe(P = 0.0160, P = 0.0019, P = 0.0173, respectively). Gender influenced measurements at depths of 50 mm with VTTQ and 25 mm with VTIQ in the right hepatic lobe(P = 0.0001, P = 0.0269). Significant differences were found between measurements with the 6C1(VTTQ) and 9L4 probes(VTIQ)(P = 0.0067), between superficial and deep measurements(P < 0.0001), and between the right and left lobes of the liver(P < 0.0001). CONCLUSION: Measurements in the right lobe and deep regions are preferable. Gender differences must be considered. BMI must be considered when assessing VTIQ technology. 展开更多
关键词 Acoustic radiation force IMPULSE Elasticityimaging techniques LIVER Reference STANDARDS Virtualtouch imaging and quantification Virtual TOUCH tissuequantification ULTRASONOGRAPHY
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Non-invasive evaluation of liver stiffness after splenectomy in rabbits with CCl_4-induced liver fibrosis 被引量:1
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作者 Ming-Jun Wang Wen-Wu Ling +3 位作者 Hong Wang Ling-Wei Meng He Cai Bing Peng 《World Journal of Gastroenterology》 SCIE CAS 2016年第46期10166-10179,共14页
AIM To investigate the diagnostic performance of liver stiffness measurement(LSM) by elastography point quantification(Elast PQ) in animal models and determine the longitudinal changes in liver stiffness by Elast PQ a... AIM To investigate the diagnostic performance of liver stiffness measurement(LSM) by elastography point quantification(Elast PQ) in animal models and determine the longitudinal changes in liver stiffness by Elast PQ after splenectomy at different stages of fibrosis.METHODS Liver stiffness was measured in sixty-eight rabbits with CCl4-induced liver fibrosis at different stages and eight healthy control rabbits by Elast PQ. Liver biopsies and blood samples were obtained at scheduled time points to assess liver function and degree of fibrosis. Thirty-one rabbits with complete data that underwent splenectomy at different stages of liver fibrosis were then included for dynamic monitoring of changes in liver stiffness by Elast PQ and liver function according to blood tests.RESULTS LSM by Elast PQ was significantly correlated with histologic fibrosis stage(r = 0.85, P < 0.001). The optimal cutoff values by Elast PQ were 11.27, 14.89, and 18.21 k Pa for predicting minimal fibrosis, moderate fibrosis, and cirrhosis, respectively. Longitudinalmonitoring of the changes in liver stiffness by Elast PQ showed that early splenectomy(especially F1) may delay liver fibrosis progression.CONCLUSION Elast PQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl4-induced liver fibrosis. In addition, liver stiffness measurements using Elast PQ can dynamically monitor the changes in liver stiffness in rabbit models, and in patients, after splenectomy. 展开更多
关键词 Fibrosis stages SPLENECTOMY Elastography point quantification Liver stiffness Non-invasive technique
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Advantages and issues of concern regarding approaches to peripheral nerve block for total hip arthroplasty 被引量:1
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作者 Marco Crisci Arturo Cuomo +4 位作者 Cira Antonietta Forte Sabrina Bimonte Gennaro Esposito Maura C Tracey Marco Cascella 《World Journal of Clinical Cases》 SCIE 2021年第36期11504-11508,共5页
In older patients with comorbidities,hip fractures are both an important and debilitating condition.Since multimodal and multidisciplinary perioperative strategies can hasten functional recovery after surgery improvin... In older patients with comorbidities,hip fractures are both an important and debilitating condition.Since multimodal and multidisciplinary perioperative strategies can hasten functional recovery after surgery improving clinical outcomes,the choice of the most effective and safest pathway represents a great challenge.A key point of concern is the anesthetic approach and above all the choice of the locoregional anesthesia combined with general or neuraxial anesthesia. 展开更多
关键词 Hip fracture Multimodal therapy Enhanced recovery after surgery Peripheral regional techniques regional analgesia techniques
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