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Responses of microbial activities and soil physical-chemical properties to the successional process of biological soil crusts in the Gurbantunggut Desert,Xinjiang 被引量:29
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作者 BingChang ZHANG XiaoBing ZHOU YuanMing ZHANG 《Journal of Arid Land》 SCIE CSCD 2015年第1期101-109,共9页
Biological soil crusts (BSCs) are capable of modifying nutrient availability to favor the establishment of biogeochemical cycles. Microbial activities serve as critical roles for both carbon and nutrient transformat... Biological soil crusts (BSCs) are capable of modifying nutrient availability to favor the establishment of biogeochemical cycles. Microbial activities serve as critical roles for both carbon and nutrient transformation in BSCs. However, little is known about microbial activities and physical-chemical properties of BSCs in the Gurbantunggut Desert, Xinjiang, China. In the present research, a sampling line with 1-m wide and 20-m long was set up in each of five typical interdune areas selected randomly in the Gurbantunggut Desert. Within each sampling line, samples of bare sand sheet, algal crusts, lichen crusts and moss crusts were randomly collected at the depth of 0-2 cm. Varia- tions of microalgal biomass, microbial biomass, enzyme activities and soil physical-chemical properties in different succession of BSCs were analyzed. The relationships between microalgal biomass, microbial biomass, enzymatic activities and soil physical-chemical properties were explored by stepwise regression. Our results indicate that micro- algal biomass, microbial biomass and most of enzyme activities increased as the BSCs developed and their highest values occurred in lichen or moss crusts. Except for total K, the contents of most soil nutrients (organic C, total N, total P, available N, available P and available K) were the lowest in the bare sand sheet and significantly increased with the BSCs development, reaching their highest values in moss crusts. However, pH values significantly decreased as the BSCs developed. Significant and positive correlations were observed between chlorophyll a and microbial biomass C. Total P and N were positively associated with chlorophyll a and microbial biomass C, whereas there was a significant and negative correlation between microbial biomass and available P. The growth of cyanobacteria and microorganism contributed C and N in the soil, which offered substrates for enzyme activities thus increasing enzyme activities. Probably, improvement in enzyme activities increased soil fertility and promoted the growth of cyanobacteria, eukary- otic algae and heterotrophic microorganism, with the accelerating succession of BSCs. The present research found that microalgal-microbial biomass and enzyme activities played important roles on the contents of nutrients in the successional stages of BSCs and helped us to understand developmental mechanism in the succession of BSCs. 展开更多
关键词 chlorophyll a microbial biomass C soil enzyme physical-chemical properties biological soil crusts
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Contribution to Comparative Study of Physical-Chemical Characteristics of Diack Basalt and Bandia Limestone for Use in Railway Engineering 被引量:3
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作者 Abdoulaye Diedhiou Libasse Sow Adama Dione 《Geomaterials》 2020年第2期25-34,共10页
This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limes... This paper presents a comparative study of Physical-Chemical characteristics of Limestone and Basalt (from Senegalese quarries). First, chemical tests show that Basalt is richer in silica 51.59% versus 2.84% for Limestone. Basalt is made up of silica minerals and essentially carbonated minerals with a CaO percentage of 50.05%. Chemical results also show that Basalt is richer in iron 12.71% versus 0.44% for Limestone. Finally, they revealed a fire loss of 40.91% for Limestone and 2.44% for Basalt. Second, physical analysis results show that Diack Basalt has the best characteristics with a flattening coefficient of 5% between 5% and 20%;the percentage of pollutants is 0.36% less than 1%;the Los Angeles coefficient is 12.21% below 15, while Bandia Limestone gives a flattening coefficient of 3%;the Los Angeles coefficient of 40.17% and the percentage of pollutant (2.4%) well above 2%. It is noted that the percentage of Limestone pollutant is too high. These important results show the net advantage of Basalt compared to Limestone in terms of physical-chemical characteristics. 展开更多
关键词 BALLAST Railways BASALT LIMESTONE physical-chemical CHARACTERISTIC
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Variation of soil physical-chemical characteristics in salt-affected soil in the Qarhan Salt Lake,Qaidam Basin 被引量:1
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作者 HUI Rong TAN Huijuan +1 位作者 LI Xinrong WANG bingyao 《Journal of Arid Land》 SCIE CSCD 2022年第3期341-355,共15页
Soil salinization has adverse effects on the soil physical-chemical characteristics.However,little is known about the changes in soil salt ion concentrations and other soil physical-chemical characteristics within the... Soil salinization has adverse effects on the soil physical-chemical characteristics.However,little is known about the changes in soil salt ion concentrations and other soil physical-chemical characteristics within the Qarhan Salt Lake and at different soil depths in the surrounding areas.Here,we selected five sampling sites(S1,S2,S3,S4,and S5)alongside the Qarhan Salt Lake and in the Xidatan segment of the Kunlun Mountains to investigate the relationship among soil salt ion concentrations,soil physical-chemical characteristics,and environmental variables in April 2019.The results indicated that most sites had strongly saline and very strongly saline conditions.The main salt ions present in the soil were Na^(+),K^(+),and Cl^(-).Soil nutrients and soil microbial biomass(SMB)were significantly affected by the salinity(P<0.05).Moreover,soil salt ions(Na^(+),K^(+),Ca2+,Mg^(2+),Cl^(-),CO_(3)^(2-),SO_(4)^(2-),and HCO_(3)^(-))were positively correlated with electrical conductivity(EC)and soil water content(SWC),but negatively related to altitude and soil depth.Unlike soil salt ions,soil nutrients and SMB were positively correlated with altitude,but negatively related to EC and SWC.Moreover,soil nutrients and SMB were negatively correlated with soil salt ions.In conclusion,soil nutrients and SMB were mainly influenced by salinity,and were related to altitude,soil depth,and SWC in the areas from the Qarhan Salt Lake to the Xidatan segment.These results imply that the soil quality(mainly evaluated by soil physical-chemical characteristics)is mainly influenced by soil salt ions in the areas surrounding the Qarhan Salt Lake.Our results provide an accurate prediction of how the soil salt ions,soil nutrients,and SMB respond to the changes along a salt gradient.The underlying mechanisms controlling the soil salt ion distribution,soil nutrients,and SMB in an extremely arid desert climate playa should be studied in greater detail in the future. 展开更多
关键词 SALINIZATION soil salt ions soil physical-chemical characteristics soil microbial biomass soil nutrient Qarhan Salt Lake
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Leguminosae plants play a key role in affecting soil physical-chemical and biological properties during grassland succession after farmland abandonment in the Loess Plateau,China 被引量:1
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作者 SUN Lin YU Zhouchang +5 位作者 TIAN Xingfang ZHANG Ying SHI Jiayi FU Rong LIANG Yujie ZHANG Wei 《Journal of Arid Land》 SCIE CSCD 2023年第9期1107-1128,共22页
Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during th... Leguminosae are an important part of terrestrial ecosystems and play a key role in promoting soil nutrient cycling and improving soil properties.However,plant composition and species diversity change rapidly during the process of succession,the effect of leguminosae on soil physical-chemical and biological properties is still unclear.This study investigated the changes in the composition of plant community,vegetation characteristics,soil physical-chemical properties,and soil biological properties on five former farmlands in China,which had been abandoned for 0,5,10,18,and 30 a.Results showed that,with successional time,plant community developed from annual plants to perennial plants,the importance of Leguminosae and Asteraceae significantly increased and decreased,respectively,and the importance of grass increased and then decreased,having a maximum value after 5 a of abandonment.Plant diversity indices increased with successional time,and vegetation coverage and above-and below-ground biomass increased significantly with successional time after 5 a of abandonment.Compared with farmland,30 a of abandonment significantly increased soil nutrient content,but total and available phosphorus decreased with successional time.Changes in plant community composition and vegetation characteristics not only change soil properties and improve soil physical-chemical properties,but also regulate soil biological activity,thus affecting soil nutrient cycling.Among these,Leguminosae have the greatest influence on soil properties,and their importance values and community composition are significantly correlated with soil properties.Therefore,this research provides more scientific guidance for selecting plant species to stabilize soil ecosystem of farmland to grassland in the Loess Plateau,China. 展开更多
关键词 secondary succession LEGUMINOSAE plant diversity plant community composition soil physical-chemical properties soil biological properties
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QSPR between Physical-Chemical Properties and Molecule Parameters of Alkanes
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作者 XU Qing-qing LI Liang-chao HU Li-ya 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第5期897-903,共7页
A set of molecule parameters, namely, N, N′, p, q, n, were used to express the structures of alkanes. A correlative model was established between certain physical-chemical properties and molecular parameters of alkan... A set of molecule parameters, namely, N, N′, p, q, n, were used to express the structures of alkanes. A correlative model was established between certain physical-chemical properties and molecular parameters of alkanes by regression method. Eight physical-chemical properties, such as evaporation heat (△vHm^20), density(D^20 ), capacity (C^20), surface tension (δ^20), boiling point (Tb), critical temperature(Tc), critical pressure(Pc) and critical volume(Vc), of fifty-six C3-C16 alkanes were calculated directly from the model in this paper. The calculated values are in good accordance with the literature ones reported for alkanes, and the correlation coefficients (R) equal or exceed 0.99 . The research results indicate that the principle of the method is simple and clear, the method is practical, the correlativity is excellent, and the predicted data are credible. 展开更多
关键词 ALKANE molecular parameters physical-chemical properties
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Physical-Chemical Aggressiveness of Solutions of Medicines as a Factor in the Rheology of the Blood inside Veins and Catheters
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作者 Aleksandr Urakov Natalia Urakova +1 位作者 Anton Kasatkin Leisan Chernova 《Journal of Chemistry and Chemical Engineering》 2014年第1期61-65,共5页
In experiments in vitro and observations in the clinic in vivo studied the state of the lumen of subcutaneous veins and blood rheology of patients after their interaction with vascular catheters and solutions of medic... In experiments in vitro and observations in the clinic in vivo studied the state of the lumen of subcutaneous veins and blood rheology of patients after their interaction with vascular catheters and solutions of medicines based on the values of temperature, volume, concentration, osmotic activity and pH. It is shown that heparin injection in blood not prevent, but solution of 4% sodium bicarbonate injection prevents blood clotting, blood clots and blockage blood clots of veins and of catheters. It is shown that the heating to a temperature of+42 ℃ with the solution of 4% sodium bicarbonate provides softening action on old dry blood clots in 1 min, and their subsequent irrigation with a warm solution of 4% sodium bicarbonate and 3% hydrogen peroxide provides complete destruction and discoloration of the remaining spots of blood during 2 s. Proposed new medicines and hygiene products for the protection of the veins and installed in them vascular catheters from blockage of blood clots, and for removing blood stains from clothes and body surface patients. 展开更多
关键词 New drugs hygiene products physical-chemical properties rheology blood.
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Compatible stability study of Xing NaoJing injection based on physical-chemical properties analysis
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作者 Dong-Li Qi Chun-Xia Liang +6 位作者 Yue-Lin Zhang Yan-Quan Gao Yue Xing Hong-Li Yan Bing Zhang Jia-Rong Xie Zhi-Dong Liu 《TMR Modern Herbal Medicine》 2019年第4期173-182,共10页
Objective:The clinical treatment of brain diseases is urgent. Xingnaojing (XNJ) injection is often used in combination with other injection drugs. Due to the possible interaction between the injections in vivo, the pa... Objective:The clinical treatment of brain diseases is urgent. Xingnaojing (XNJ) injection is often used in combination with other injection drugs. Due to the possible interaction between the injections in vivo, the particle size, osmotic pressure, pH value change and component stability decrease, that is one of the important factors causing various adverse reactions. Based on the above situation, this study investigated the physical properties and chemical composition changes of XNJ injection and its compatibility solvent and 13 kinds of clinical injection, speculated the possible interactions between the drugs in vivo from the perspective of in vitro compatibility stability, find out the safety risks of adverse reactions and provide guidance for the safe and rational use of XNJ injection. Methods:According to the clinical application, XNJ injection was mixed with 13 combination injections based on 250 mL 5% glucose injection, and placed at room temperature for 6 h. Then, the clarity, particle size, pH, osmolality, and the contents of camphor, d-borneol, and muscone of the compatible solutions were detected at 0, 1, 2, 4, and 6 h, respectively. Results:The results showed that the physical-chemical properties of compatibility solution were slightly influenced when XNJ was combined with Alprostadil injection and Danhong injection. The change of particle size and the degradation of muscone content were the main factors affecting the compatibility stability of XNJ injection, indicating that there are some problems in compatibility stability, which may be one of the causes of clinical adverse reactions. Conclusion:This study suggests that XNJ injection in combination with other injections during intravenous administration should be performed cautiously. 展开更多
关键词 Xingnaojing injection STABILITY Compatibility physical-chemical properties Adverse drug reaction MUSCONE d-borneol
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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data 被引量:2
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作者 Yunping Chen Jie Hu +6 位作者 Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1164-1178,共15页
Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while r... Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities. 展开更多
关键词 ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data
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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat 被引量:1
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作者 Zhikai Cheng Xiaobo Gu +5 位作者 Yadan Du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian Chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1523-1540,共18页
In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge m... In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching. 展开更多
关键词 mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle
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Association between triglyceride-glucose index and colorectal polyps:A retrospective cross-sectional study 被引量:1
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作者 Ya-Jie Teng Ying-Xue Yang +5 位作者 Jing-Jing Yang Qiu-Yan Lu Jia-Yi Shi Jian-Hao Xu Jie Bao Qing-Hua Wang 《World Journal of Gastrointestinal Endoscopy》 2024年第2期55-63,共9页
BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses met... BACKGROUND Colorectal polyps(CPs)are frequently occurring abnormal growths in the colorectum,and are a primary precursor of colorectal cancer(CRC).The triglyceride-glucose(TyG)index is a novel marker that assesses metabolic health and insulin resistance,and has been linked to gastrointestinal cancers.AIM To investigate the potential association between the TyG index and CPs,as the relation between them has not been documented.METHODS A total of 2537 persons undergoing a routine health physical examination and colonoscopy at The First People's Hospital of Kunshan,Jiangsu Province,China,between January 2020 and December 2022 were included in this retrospective cross-sectional study.After excluding individuals who did not meet the eligibility criteria,descriptive statistics were used to compare characteristics between patients with and without CPs.Logistic regression analyses were conducted to determine the associations between the TyG index and the prevalence of CPs.The TyG index was calculated using the following formula:Ln[triglyceride(mg/dL)×glucose(mg/dL)/2].The presence and types of CPs was determined based on data from colonoscopy reports and pathology reports.RESULTS A nonlinear relation between the TyG index and the prevalence of CPs was identified,and exhibited a curvilinear pattern with a cut-off point of 2.31.A significant association was observed before the turning point,with an odds ratio(95% confidence interval)of 1.70(1.40,2.06),P<0.0001.However,the association between the TyG index and CPs was not significant after the cut-off point,with an odds ratio(95% confidence interval)of 0.57(0.27,1.23),P=0.1521.CONCLUSION Our study revealed a curvilinear association between the TyG index and CPs in Chinese individuals,suggesting its potential utility in developing colonoscopy screening strategies for preventing CRC. 展开更多
关键词 Triglyceride-glucose index Colorectal polyps Colorectal cancer Insulin resistance Cross-sectional study
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Renal resistive index measurements by ultrasound in patients with liver cirrhosis:Magnitude and associations with renal dysfunction 被引量:1
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作者 Himanshu Surya Ramesh Kumar +2 位作者 Rajeev Nayan Priyadarshi Sabbu Surya Prakash Sudhir Kumar 《World Journal of Radiology》 2024年第6期221-231,共11页
BACKGROUND The hemodynamic alterations seen in liver cirrhosis lead to renal vasoconstriction,ultimately causing acute kidney injury(AKI).The renal resistive index(RRI)is the most common Doppler ultrasound variable fo... BACKGROUND The hemodynamic alterations seen in liver cirrhosis lead to renal vasoconstriction,ultimately causing acute kidney injury(AKI).The renal resistive index(RRI)is the most common Doppler ultrasound variable for measuring intrarenal vascular resistance.AIM To evaluate the association of the RRI with AKI in patients with liver cirrhosis and to identify risk factors for high RRI.METHODS This was a prospective observational study,where RRI was measured using Doppler ultrasound in 200 consecutive hospitalized patients with cirrhosis.The association of RRI with AKI was studied.The receiver operating characteristic(ROC)curve analysis was utilized to determine discriminatory cut-offs of RRI for various AKI phenotypes.Multivariate analysis was conducted to determine the predictors of high RRI.RESULTS The mean patient age was 49.08±11.68 years,with the majority(79.5%)being male;the predominant etiology of cirrhosis was alcohol(39%).The mean RRI for the study cohort was 0.68±0.09,showing a progressive increase with higher Child-Pugh class of cirrhosis.Overall,AKI was present in 129(64.5%)patients.The mean RRI was significantly higher in patients with AKI compared to those without it(0.72±0.06 vs 0.60±0.08;P<0.001).A total of 82 patients(41%)had hepatorenal syndrome(HRS)-AKI,29(22.4%)had prerenal AKI(PRA),and 18(13.9%)had acute tubular necrosis(ATN)-AKI.The mean RRI was significantly higher in the ATN-AKI(0.80±0.02)and HRS-AKI(0.73±0.03)groups than in the PRA(0.63±0.07)and non-AKI(0.60±0.07)groups.RRI demonstrated excellent discriminatory ability in distinguishing ATN-AKI from non-ATN-AKI(area under ROC curve:93.9%).AKI emerged as an independent predictor of high RRI(adjusted odds ratio[OR]:11.52),and high RRI independently predicted mortality among AKI patients(adjusted OR:3.18).CONCLUSION In cirrhosis patients,RRI exhibited a significant association with AKI,effectively differentiated between AKI phenotypes,and predicted AKI mortality. 展开更多
关键词 Renal resistive index CIRRHOSIS Acute kidney injury Hepatorenal syndrome Renal Doppler
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Three-dimensional choroidal vascularity index and choroidal thickness in fellow eyes of acute and chronic primary angle-closure using swept-source optical coherence tomography 被引量:1
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作者 Hai-Li Huang Guan-Hong Wang +1 位作者 Liang-Liang Niu Xing-Huai Sun 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期42-52,共11页
AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of... AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma. 展开更多
关键词 choroidal thickness choroidal vascularity index swept-source optical coherence tomography acute primary angle-closure chronic primary angle-closure glaucoma
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On traceable iterated line graph and hamiltonian path index
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作者 NIU Zhao-hong XIONG Li-ming YANG Wei-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期239-252,共14页
Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥2.In this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characteri... Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥2.In this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characterization of G for which L^(n)(G)has a hamiltonian path.As applications,we use this characterization to give several upper bounds on the hamiltonian path index of a graph. 展开更多
关键词 iterated line graph TRACEABLE hamiltonian index hamiltonian path index
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Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation
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作者 Qing YAN Jia-Qi LIANG +5 位作者 Yi-De YUAN Yuan LI Jia-Li FAN Wen-Huan WU Pan XU Jia-Hong XUE 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第2期200-210,共11页
BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence... BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an Jiaotong University were included in this study.The participants were grouped based on cumulative TyG index values tertiles within 3 months after ablation.Cox regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF recurrence.The predictive value of all risk factors was assessed by receiver operating curve analysis.RESULTS There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values tertiles.After adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,P<0.001)had a higher risk of AF recurrence than those in the low cumulative TyG index group.The restricted cubic spline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index values.When considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after RFCA.Monitoring longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence. 展开更多
关键词 ATRIAL FIBRILLATION index
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An evaluation of ureteral diameter ratio and vesicoureteral reflux index in the treatment of primary vesicoureteral reflux
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作者 Yusuf Atakan Baltrak Nebil Akdogan +3 位作者 Mutlu Deger Volkan Izol Ibrahim Atilla Aridogan Nihat Satar 《Asian Journal of Urology》 CSCD 2024年第3期437-442,共6页
Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and co... Objective:Vesicoureteral reflux(VUR)index is a simple,validated tool that reliably predicts significant improvement and spontaneous resolution of primary reflux in children.The aim of this study was to evaluate and compare the ureter diameter ratio(UDR)and VUR index(VURx)of patients treated with endoscopic injection(EI)and ureteroneocystostomy(UNC)methods in the pediatric age group due to primary VUR.Methods:Patients under the age of 18 years old who underwent EI and UNC with the diagnosis of primary VUR between January 2011 and September 2021 were determined as the participants.The UDR was assessed using voiding cystourethrography,and the VURx score was determined prior to treatment based on hospital records included in the study.Results:A total of 255 patients,60(23.5%)boys and 195(76.5%)girls,with a mean age of 76.5(range 13.0e204.0)months,were included in the study.EI was applied to 130(51.0%)patients and UNC was applied to 125(49.0%)patients due to primary VUR.The optimum cut-off for the distal UDR was obtained as 0.17 with sensitivity and specificity of 73.0%and 63.0%,respectively.The positive and negative predictive values were 66.0%and 70.0%,respectively.Conclusion:When the UDR and VURx score are evaluated together for the surgical treatment of primary VUR in the pediatric age group,it is thought that it may be useful in predicting the clinical course of the disease and evaluating surgical treatment options. 展开更多
关键词 Distal ureter diameter ratio Vesicoureteral reflux Vesicoureteral reflux index management Vesicoureteral reflux index
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Assessment on eco-environmental quality of the Yellow River Basin by considering desertification index
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作者 AN Min MENG Fan +4 位作者 HE Weijun XUE Fang SONG Mengfei XIE Ping WANG Bei 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3275-3292,共18页
Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have pa... Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of desertification.It is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the region.In this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to 2021.Furthermore,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the YRB.The research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the EEQ.Among the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the YRB.The remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the EEQ.Furthermore,after the interaction with natural factors,the explanatory power of human factors gradually increases over time.The spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the influence.Human activities have a strong negative impact on the EEQ and a weak positive impact. 展开更多
关键词 Ecological environment quality Desertification index Desertification remote sensing ecological index Driving factors Yellow River Basin
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Early peripheral perfusion index predicts 28-day outcome in patients with septic shock
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作者 Cheng Chi Hao Gong +2 位作者 Kai Yang Peng Peng Xiaoxia Zhang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第5期372-378,共7页
BACKGROUND:To investigate the prognostic value of the peripheral perfusion index(PPI)in patients with septic shock.METHODS:This prospective cohort study,conducted at the emergency intensive care unit of Peking Univers... BACKGROUND:To investigate the prognostic value of the peripheral perfusion index(PPI)in patients with septic shock.METHODS:This prospective cohort study,conducted at the emergency intensive care unit of Peking University People's Hospital,recruited 200 patients with septic shock between January 2023 and August 2023.These patients were divided into survival(n=84)and death(n=116)groups based on 28-day outcomes.Clinical evaluations included laboratory tests and clinical scores,with lactate and PPI values assessed upon admission to the emergency room and at 6 h and 12 h after admission.Risk factors associated with mortality were analyzed using univariate and multivariate Cox regression analyses.Receiver operator characteristic(ROC)curve was used to assess predictive performance.Mortality rates were compared,and Kaplan-Meier survival plots were created.RESULTS:Compared to the survival group,patients in the death group were older and had more severe liver damage and coagulation dysfunction,necessitating higher norepinephrine doses and increased fl uid replacement.Higher lactate levels and lower PPI levels at 0 h,6 h,and 12 h were observed in the death group.Multivariate Cox regression identifi ed prolonged prothrombin time(PT),decreased 6-h PPI and 12-h PPI as independent risk factors for death.The area under the curves for 6-h PPI and 12-h PPI were 0.802(95%CI 0.742-0.863,P<0.001)and 0.945(95%CI 0.915-0.974,P<0.001),respectively,which were superior to Glasgow Coma Scale(GCS),Sequential Organ Failure Assessment(SOFA)scores(0.864 and 0.928).Cumulative mortality in the low PPI groups at 6 h and 12 h was signifi cantly higher than in the high PPI groups(6-h PPI:77.52%vs.22.54%;12-h PPI:92.04%vs.13.79%,P<0.001).CONCLUSION:PPI may have value in predicting 28-day mortality in patients with septic shock. 展开更多
关键词 Peripheral perfusion index Septic shock PROGNOSIS Predictive value
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Actuality and underlying mechanisms of systemic immuneinflammation index and geriatric nutritional risk index prognostic value in hepatocellular carcinoma
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作者 Konstantin Y Tchilikidi 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期260-265,共6页
This editorial contains comments on the article“Correlation between preoperative systemic immune inflammation index,nutritional risk index,and prognosis of radical resection of liver cancer”in a recent issue of the ... This editorial contains comments on the article“Correlation between preoperative systemic immune inflammation index,nutritional risk index,and prognosis of radical resection of liver cancer”in a recent issue of the World Journal of Gastrointestinal Surgery.It pointed out the actuality and importance of the article and focused primarily on the underlying mechanisms making the systemic immuneinflammation index(SII)and geriatric nutritional risk index(GNRI)prediction features valuable.There are few publications on both SII and GNRI together in hepatocellular carcinoma(HCC)and patient prognosis after radical surgery.Neutrophils release cytokines,chemokines,and enzymes,degrade extracellular matrix,reduce cell adhesion,and create conditions for tumor cell invasion.Neutrophils promote the adhesion of tumor cells to endothelial cells,through physical anchoring.That results in the migration of tumor cells.Pro-angiogenic factors from platelets enhance tumor angiogenesis to meet tumor cell supply needs.Platelets can form a protective film on the surface of tumor cells.This allows avoiding blood flow damage as well as immune system attack.It also induces the epithelial-mesenchymal transformation of tumor cells that is critical for invasiveness.High SII is also associated with macro-and microvascular invasion and increased numbers of circulating tumor cells.A high GNRI was associated with significantly better progression-free and overall survival.HCC patients are a very special population that requires increased attention.SII and GNRI have significant survival prediction value in both palliative treatment and radical surgery settings.The underlying mechanisms of their possible predictive properties lie in the field of essential cancer features.Those features provide tumor nutrition,growth,and distribution throughout the body,such as vascular invasion.On the other hand,they are tied to the possibility of patients to resist tumor progression and development of complications in both postoperative and cancer-related settings.The article is of considerable interest.It would be helpful to continue the study follow-up to 2 years and longer.External validation of the data is needed. 展开更多
关键词 Systemic immune-inflammation index Geriatric nutritional risk index Radical surgery Transarterial chemoembolization Hepatocellular carcinoma Prognosis
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Advancing prognostic precision in gastric cancer with an immunoinflammatory index
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作者 Hong-Mei Zhang Guo-Hua Wang +1 位作者 Shan-Wen Sun Lei Yuan 《World Journal of Gastroenterology》 SCIE CAS 2024年第44期4754-4758,共5页
Gastric cancer remains a major global health challenge with high morbidity and mortality rates.Recent advancements in immunology and inflammation research have highlighted the crucial roles that these biological proce... Gastric cancer remains a major global health challenge with high morbidity and mortality rates.Recent advancements in immunology and inflammation research have highlighted the crucial roles that these biological processes play in tumor progression and patient outcomes.This has sparked new interest in developing prognostic biomarkers that integrate these two key biological processes.In this letter,we discuss the recent study by Ba et al,which proposed a novel prognostic immunoinflammatory index for patients with gastric cancer.We underscore the importance of this research,its potential impact on medical practice,and the prospective avenues for further investigation in this rapidly emerging area of study. 展开更多
关键词 Gastric cancer Immunoinflammatory index Prognostic biomarkers INFLAMMATION IMMUNOLOGY
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A Transparent Photoresist Made of Titanium Dioxide Nanoparticle-Embedded Acrylic Resin with a Tunable Refractive Index for UV-Imprint Lithography
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作者 Yinglu Liu Dan Wang +7 位作者 Changlin Liu Qianqian Hao Jian Li Jie-Xin Wang Xiuyun Chen Peng Zhong Xibin Shao Jian-Feng Chen 《Engineering》 SCIE EI CAS CSCD 2024年第6期96-104,共9页
Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of ... Transparent photoresists with a high refractive index(RI)and high transmittance in visible wavelengths have promising functionalities in optical fields.This work reports a kind of tunable optical material composed of titanium dioxide nanoparticles embedded in acrylic resin with a high RI for ultraviolet(UV)-imprint lithography.The hybrid film exhibits a tunable RI of up to 1.67(589 nm)after being cured by UV light,while maintaining both a high transparency of over 98%in the visible light range and a low haze of less than 0.05%.The precision machining of optical microstructures can be imprinted easily and efficiently using the hybrid resin,which acts as a light guide plate(LGP)to guide the light from the side to the top in order to conserve the energy of the display device.These preliminary studies based on both laboratory and commercial experiments pave the way for exploiting the unparalleled optical properties of nanocomposite resins and promoting their industrial application. 展开更多
关键词 PHOTORESIST Tunable refractive index Hanson solubility Ultraviolet imprint Organic-inorganic composites
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