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Diagnostic efficacy of virtual organ computer-assisted analysis in measuring the volume ratio of subchorionic hematoma with serum progesterone
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作者 Lin-Ling Shen Jing Shi +2 位作者 Chang-Wei Ding Gao-Le Dai Qi Ma 《World Journal of Clinical Cases》 SCIE 2024年第17期3053-3060,共8页
BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcome... BACKGROUND Subchorionic hematoma(SCH)is a common complication in early pregnancy characterized by the accumulation of blood between the uterine wall and the chorionic membrane.SCH can lead to adverse pregnancy outcomes such as miscarriage,preterm birth,and other complications.Early detection and accurate assessment of SCH are crucial for appropriate management and improved pregnancy outcomes.AIM To evaluate the diagnostic efficacy of virtual organ computer-assisted analysis(VOCAL)in measuring the volume ratio of SCH to gestational sac(GS)combined with serum progesterone on early pregnancy outcomes in patients with SCH.METHODS A total of 153 patients with SCH in their first-trimester pregnancies between 6 and 11 wk were enrolled.All patients were followed up until a gestational age of 20 wk.The parameters of transvaginal two-dimensional ultrasound,including the circumference of SCH(Cs),surface area of SCH(Ss),circumference of GS(Cg),and surface area of GS(Sg),and the parameters of VOCAL with transvaginal three-dimensional ultrasound,including the three-dimensional volume of SCH(3DVs)and GS(3DVg),were recorded.The size of the SCH and its ratio to the GS size(Cs/Cg,Ss/Sg,3DVs/3DVg)were recorded and compared.RESULTS Compared with those in the normal pregnancy group,the adverse pregnancy group had higher Cs/Cg,Ss/Sg,and 3DVs/3DVg ratios(P<0.05).When 3DVs/3DVg was 0.220,the highest predictive performance predicted adverse pregnancy outcomes,resulting in an AUC of 0.767,and the sensitivity,specificity were 70.2%,75%respectively.VOCAL measuring 3DVs/3DVg combined with serum progesterone gave a diagnostic AUC of 0.824 for early pregnancy outcome in SCH patients,with a high sensitivity of 82.1%and a specificity of 72.1%,which showed a significant difference between AUC.CONCLUSION VOCAL-measured 3DVs/3DVg effectively quantifies the severity of SCH,while combined serum progesterone better predicts adverse pregnancy outcomes. 展开更多
关键词 Subchorionic hematoma Virtual organ computer-assisted analysis Gestational sac Serum progesterone Ultrasound parameters Adverse pregnancy outcomes
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Thermal Analysis of Organic Light Emitting Diodes Based on Basic Heat Transfer Theory 被引量:1
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作者 张稳稳 吴朝新 +3 位作者 刘迎文 董军 严学文 侯洵 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期139-143,共5页
We investigate the thermal characteristics of standard organic light-emitting diodes (OLEDs) using a simple and clear 1D thermal model based on the basic heat transfer theory. The thermal model can accurately estima... We investigate the thermal characteristics of standard organic light-emitting diodes (OLEDs) using a simple and clear 1D thermal model based on the basic heat transfer theory. The thermal model can accurately estimate the device temperature, which is linearly with electrical input power. The simulation results show that there is almost no temperature gradient within the OLED device working under steady state conditions. Furthermore, thermal analysis simulation results show that the surface properties (convective heat transfer coetficient and surface emissivity) of the substrate or cathode can significantly affect the temperature distribution of the OLED. 展开更多
关键词 OLEDS Thermal analysis of Organic Light Emitting Diodes Based on Basic Heat Transfer Theory EML
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Water Quality Evaluation and Analysis on the Causes of Pollution for Groundwater Sources in Yantai, China
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作者 PanpanMeng Henghua Zhu +1 位作者 Jing Wang Baoping Lv 《Journal of Environmental Science and Engineering(A)》 2015年第2期99-103,共5页
Based on the investigation for the 14 groundwater sources, the water quality of the groundwater sources had been analyzed, using the evaluation method of the combination of inorganic and organic index instead of the t... Based on the investigation for the 14 groundwater sources, the water quality of the groundwater sources had been analyzed, using the evaluation method of the combination of inorganic and organic index instead of the traditional method which was only based on inorganic index. The results showed that the quality of 12 groundwater sources satisfied class III standard of groundwater quality and other two exceeded class III standard. There were one groundwater source, whose water quality reached class 1 standard, and five groundwater sources, whose water quality reached class II standard. There were seven groundwater sources, in which the fluorine, an organic pollutant, was detected. The results showed that the groundwater resources in Yantai City were less polluted and the main pollutant in groundwater was nitrate. According to the analytical data and the environmental conditions of groundwater sources, the conclusion was drawn that the agriculture and rural non-point pollution were the main reasons of groundwater pollution. 展开更多
关键词 Groundwater sources water quality evaluation groundwater pollution organic pollution analysis.
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Clinical analysis of different periods of liver transplantation at an organ transplantation centre
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作者 梁廷波 《外科研究与新技术》 2003年第2期129-130,共2页
Objective To summarize our clinical experience in liver transplantation while considering the background in this filed in China. Methods Ninety-five patients who had received liver transplantation from April 1993 to M... Objective To summarize our clinical experience in liver transplantation while considering the background in this filed in China. Methods Ninety-five patients who had received liver transplantation from April 1993 to March 2002 were analyzed retrospectively. Three periods were defined objectively as period Ⅰ(1993-1997),Ⅱ(1999) and Ⅲ(2000 -2002). Operative techniques, recipients, original diseases, complications and survival rates were compared among the three periods. Results Malignant liver lesions were the main cause for liver transplantation in period Ⅰ and Ⅱ. The ratio of number of malignant disease to total recipients decreased gradually from period Ⅰ to Ⅱ (100%, 53% and 35%, respectively). The 1-year survival rate in patients with benign liver disease was 85 % and the total operative mortality was 5% in period Ⅲ. The incidence of hepatitis B virus reactivation or reinfection was 24% twelve months after liver transplantation. Vascular complication decreased but biliary complications did 展开更多
关键词 of Clinical analysis of different periods of liver transplantation at an organ transplantation centre
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Correspondence of bubble size and frother partitioning in flotation 被引量:5
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作者 张炜 Jan E.Nesset James A.Finch 《Journal of Central South University》 SCIE EI CAS 2014年第6期2383-2390,共8页
The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most impor... The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation achieved.Meanwhile,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles burst.This causes the increased concentration in the froth compared to the bulk concentration,named as frother partitioning.Partitioning reflects the adsorption of frother on bubbles and how to influence bubble size is not known.There currently exists no such a topic aiming to link these two key parameters.To fill this vacancy,the correspondence between bubble size and frother partitioning was examined.Bubble size was measured by sampling-for-imaging(SFI)technique.Using total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was determined.Measurements have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the froth.The results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and D32.The CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction. 展开更多
关键词 FLOTATION frother bubble size frother partitioning total organic carbon (TOC) analysis concentration gradient
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Compositional and Structural Difference of Fulvic Acid from Black Soil Applied with Different Organic Materials: Assessment After Three Years 被引量:3
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作者 LI Jian-ming WU Jing-gui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第10期1865-1871,共7页
Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural Universit... Knowledge of different effects of various organic materials on soil humic substance is important for both environmental safety and sustainable agriculture.A pot experiment was conducted at Jilin Agricultural University,Jilin Province in northeast China to discover the influence of herb residue,animal excrement,woody residue,animal remnant on fulvic acid(FA) composition and structure using differential thermal analysis-thermogravimetric(DTA-TG),fourier transform infrared spectroscopy(FTIR) and elemental analysis.DTA-TG showed the range of peak temperature in the first exothermic reaction increased following the trend: CK〉herb residue〉animal excrement〉woody residue=animal remnant,and the most weight loss was observed in animal excrement.Moreover,the second exothermic reaction of CK-and animal excrement-FA was presented as double peaks,the order of weight loss in that area was animal remnant〉CK〉woody residue〉animal excrement〉herb residue.According to FTIR,herb residue displayed higher adsorption intensity at 2 950,1 420,1 240 and 1 030 cm-1,animal excrement was in reverse.At the same time,herb residue-and animal excrement-FA had an absorption peak at 1 720 cm-1,while other organic materials didn't have this peak.As elemental analysis showed,FA isolated from various treatments was significantly distinct.It was clearly shown from our results that FA composition and structure in amended soils may be affected in different ways and at various extents on dependence of the nature and origin of amendment. 展开更多
关键词 different organic materials fulvic acid DTA-TG FTIR elemental analysis
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Comparison of three-dimensional fluorescence analysis methods for predicting formation of trihalomethanes and haloacetic acids 被引量:4
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作者 Nicolás M.Peleato Robert C.Andrews 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第1期159-167,共9页
This work investigated the application of several fluorescence excitation–emission matrix analysis methods as natural organic matter(NOM) indicators for use in predicting the formation of trihalomethanes(THMs) an... This work investigated the application of several fluorescence excitation–emission matrix analysis methods as natural organic matter(NOM) indicators for use in predicting the formation of trihalomethanes(THMs) and haloacetic acids(HAAs). Waters from four different sources(two rivers and two lakes) were subjected to jar testing followed by 24 hr disinfection by-product formation tests using chlorine. NOM was quantified using three common measures: dissolved organic carbon, ultraviolet absorbance at 254 nm, and specific ultraviolet absorbance as well as by principal component analysis, peak picking,and parallel factor analysis of fluorescence spectra. Based on multi-linear modeling of THMs and HAAs, principle component(PC) scores resulted in the lowest mean squared prediction error of cross-folded test sets(THMs: 43.7(μg/L)^2, HAAs: 233.3(μg/L)^2). Inclusion of principle components representative of protein-like material significantly decreased prediction error for both THMs and HAAs. Parallel factor analysis did not identify a protein-like component and resulted in prediction errors similar to traditional NOM surrogates as well as fluorescence peak picking. These results support the value of fluorescence excitation–emission matrix–principal component analysis as a suitable NOM indicator in predicting the formation of THMs and HAAs for the water sources studied. 展开更多
关键词 Natural organic matter Fluorescence Principal component analysis PARAFAC Disinfection byproducts Drinking water
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Chemical characteristics and source apportionment of PM_(2.5) between heavily polluted days and other days in Zhengzhou, China 被引量:24
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作者 Nan Jiang Qiang Li +5 位作者 Fangcheng Su Qun Wang Xue Yu Panru Kang Ruiqin Zhang Xiaoyan Tang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第4期188-198,共11页
PM(2.5) samples were collected in Zhengzhou during 3 years of observation, and chemical characteristics and source contribution were analyzed. Approximately 96% of the daily PM(2.5) concentrations and annual avera... PM(2.5) samples were collected in Zhengzhou during 3 years of observation, and chemical characteristics and source contribution were analyzed. Approximately 96% of the daily PM(2.5) concentrations and annual average values exceeded the Chinese National Ambient Air Quality Daily and Annual Standards, indicating serious PM(2.5) pollution. The average concentration of water-soluble inorganic ions was 2.4 times higher in heavily polluted days(daily PM32.5 concentrations &gt; 250 μg/mand visibility &lt; 3 km) than that in other days, with sulfate, nitrate, and ammonium as major ions. According to the ratio of NO-3/SO2-4,stationary sources are still the dominant source of PM(2.5) and vehicle emission could not be ignored. The ratio of secondary organic carbon to organic carbon indicated that photochemical reactivity in heavily polluted days was more intense than in other days.Crustal elements were the most abundant elements, accounting for more than 60% of 23 elements. Chemical Mass Balance results indicated that the contributions of major sources(i.e., nitrate, sulfate, biomass, carbon and refractory material, coal combustion, soil dust,vehicle, and industry) of PM(2.5) were 13%, 16%, 12%, 2%, 14%, 8%, 7%, and 8% in heavily polluted days and 20%, 18%, 9%, 2%, 27%, 14%, 15%, and 9% in other days, respectively.Extensive combustion activities were the main sources of polycyclic aromatic hydrocarbons during the episode(Jan 1-9, 2015) and the total benzo[a]pyrene equivalency concentrations in heavily polluted days present significant health threat. Because of the effect of regional transport, the pollution level of PM(2.5) in the study area was aggravated. 展开更多
关键词 PM2.5 Water soluble inorganic ions Secondary organic carbon CMB Back trajectory analysis
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Identifying the major fluorescent components responsible for ultrafiltration membrane fouling in different water sources 被引量:6
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作者 Weiguang Sun Jun Nan +1 位作者 Jia Xing Jiayu Tian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第7期215-223,共9页
Three-dimensional fluorescence excitation–emission matrix(EEM) coupled with parallel factor analysis(PARAFAC) was performed for a total of 18 water samples taken from three water sources(two lakes and one wastew... Three-dimensional fluorescence excitation–emission matrix(EEM) coupled with parallel factor analysis(PARAFAC) was performed for a total of 18 water samples taken from three water sources(two lakes and one wastewater treatment plant(WWTP) secondary effluent),with the purpose of identifying the major ultrafiltration(UF) membrane foulants in different water sources. Three fluorescent components(C1, C2 and C3) were identified,which represented terrestrially derived humic-like substances(C1), microbially derived humic-like substances(C2), and protein-like substances(C3). The correlations between the different fluorescent components and UF membrane fouling were analyzed. It was shown that for the WWTP secondary effluent, all three components(C1, C2 and C3) made a considerable contribution to the irreversible and total fouling of the UF membrane.However, for the two lakes, only the C3 exhibited a strong correlation with membrane fouling, indicating that the protein-like substances were the major membrane foulants in the lake waters. Significant attachment of C1, C2 and C3 to the UF membrane was also confirmed by mass balance analyses for the WWTP secondary effluent; while the attachment of C1 and C2 was shown to be negligible for the two lakes. The results may provide basic formation for developing suitable fouling control strategies for sustainable UF processes. 展开更多
关键词 Membrane fouling Organic substances Three-dimensional fluorescence matrix Parallel factor analysis Correlation analysis
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A new technique helps to uncover unknown peptides and disinfection by-products in water 被引量:5
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作者 Susan D.Richardson Cristina Postigo 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第4期6-8,共3页
Environmental water samples can be extremely complex,with potentially thousands of molecules that can derive from natural organic matter(NOM)and thousands that derive from anthropogenic contaminants.As complex as th... Environmental water samples can be extremely complex,with potentially thousands of molecules that can derive from natural organic matter(NOM)and thousands that derive from anthropogenic contaminants.As complex as these samples are,drinking water can be even more complex.Due to disinfectants that are used to treat drinking water(e.g.,chlorine,chloramines, 展开更多
关键词 Disinfection by-products(DBPs) Drinking water Halogenated peptides Liquid chromatography Natural organic matter(NOM) Non-targeted analysis Tandem mass spectrometry Water contaminants
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Boron Oxide Glasses and Nanocomposites: Synthetic, Structural and Statistical Approach 被引量:1
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作者 Hristo Hristov Miroslava Nedyalkova +1 位作者 Sergio Madurga Vasil Simeonov 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2017年第6期535-540,共6页
Three different precursors of boron-aqua and glycerol solutions of boric acid and ethanol solution of trimethyl borate were used for the preparation of organic–inorganic advanced materials. The films and bulk materia... Three different precursors of boron-aqua and glycerol solutions of boric acid and ethanol solution of trimethyl borate were used for the preparation of organic–inorganic advanced materials. The films and bulk materials samples were heat treated at 100, 400, 800?C for 2 h. The hybrid samples were stable and transparent until 100?C. The further increase of temperature to 400?C led to destruction of samples, and at 800?C they were molten. The structural changes during the pyrolysis were studied by Fourier transform infrared spectroscopy, differential thermal analysis, and X-ray diffraction. Details of surface morphology were observed by scanning electron microscopy. The obtained BO_3 and BO_4 groups were identified in the molten materials after pyrolysis. The quantities and order of borate structural units as well as residual carbon in the networks depended on boron precursor type. PVA/PEG/B_2O_3 hybrid materials were proved to be appropriate precursors for synthesizing borate and carboborate glass and carbon/borate glass nanocomposites. To access the impact of the experimental conditions on the structural changes of the nanocomposites, cluster analysis of the IR-spectral data was used as a classification method. 展开更多
关键词 Organic–inorganic hybrid materials Borate glass Nanocomposites Cluster analysis
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