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Combined Promoting Effects of Specific Organic Functional Groups and Alumina Surface Characteristics for the Design of a Highly Efficient NiMo/Al_(2)O_(3) Hydrodesulfurization Catalyst 被引量:2
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作者 Li Huifeng Li Mingfeng +2 位作者 Zhang Le Wang Wei Nie Hong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期1-11,共11页
To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were investigated.First,the correlation betwe... To prepare a highly efficient NiMo/Al_(2)O_(3) hydrodesulfurization catalyst,the combined effects of specific organic functional groups and alumina surface characteristics were investigated.First,the correlation between the surface characteristics of four different alumina and the existing Mo species states was established.It was found that the Mo equilibrium adsorption capacity can be used as a specific descriptor to quantitatively evaluate the changes in surface characteristics of different alumina.A lower Mo equilibrium adsorption capacity for alumina means weaker metal-support interaction and the loaded Mo species are easier to transform into MoS2.However,the Mo-O-Al bonds still exist at the metal-support interface.The introduction of cationic surfactant hecadecyl trimethyl ammonium bromide(CTAB)can further improve Mo species dispersion through electrostatic attraction with Mo anions and interaction of its alkyl chain with the alumina surface;meanwhile,the introduction of ethylenediamine tetraacetic acid(EDTA)can complex with Ni ions to enhance the Ni-promoting effect on Mo.Therefore,the NiMo catalyst designed using alumina with lower Mo equilibrium adsorption capacity and the simultaneous addition of EDTA and CTAB exhibits the highest hydrodesulfurization activity for 4,6-dimethyl dibenzothiophene because of its proper metal-support interaction and more well-dispersed Ni-Mo-S active phases. 展开更多
关键词 ALUMINA Mo equilibrium adsorption capacity organic functional groups metal-support interaction HYDRODESULFURIZATION
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Density Functional Theory Calculations of Charge-Induced Spin Polarization in Pentacene
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作者 任俊峰 张燕如 +1 位作者 原晓波 胡贵超 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期519-522,I0003,共5页
Based on density functional theory (DFT) calculations, we investigate the spin-related properties of spinless-hole injected organic molecule pentacene (Pc). DFT calculations reveal that there is spontaneous spin p... Based on density functional theory (DFT) calculations, we investigate the spin-related properties of spinless-hole injected organic molecule pentacene (Pc). DFT calculations reveal that there is spontaneous spin polarization in Pc when spinless-hole is injected. The chargeinduced magnetic moment of Pc increases linearly with the increasing of the extra hole charge amount and its maximum can be up to 1 μB per injected spinless-hole per Pc molecule. The magnetic moment is expected due to the injected unpaired charge. The injected hole will preferably ll the spin-splitted carbon pz orbitals, which makes the Pc molecule spin polarize. 展开更多
关键词 Organic spintronics Spontaneous spin polarization Density functional theory PENTACENE
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Functional topography of the corpus callosum investigated by DTI and f MRI 被引量:6
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作者 Mara Fabri Chiara Pierpaoli +1 位作者 Paolo Barbaresi Gabriele Polonara 《World Journal of Radiology》 CAS 2014年第12期895-906,共12页
This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, ... This short review examines the most recent functional studies of the topographic organization of the human corpus callosum, the main interhemispheric commissure. After a brief description of its anatomy, development, microstructure, and function, it examines and discusses the latest findings obtained using diffusion tensor imaging(DTI) and tractography(DTT) and functional magnetic resonance imaging(f MRI), three recently developed imaging techniques that have significantly expanded and refined our knowledge of the commissure. While DTI and DTT have been providing insights into its microstructure, integrity and level of myelination, f MRI has been the key technique in documenting the activation of white matter fibers, particularly in the corpus callosum. By combining DTT and f MRI it has been possible to describe the trajectory of the callosal fibers interconnecting the primary olfactory, gustatory, motor, somatic sensory, auditory and visual cortices at sites where the activation elicited by peripheral stimulation was detected by fMRI. These studies have demonstrated the presence of callosal fiber tracts that cross the commissure at the level of the genu, body, and splenium, at sites showing f MRI activation. Altogether such findings lend further support to the notion that the corpus callosum displays a functional topographic organization that can be explored with f MRI. 展开更多
关键词 CORPUS callosum INTERHEMISPHERIC transfer functional magnetic resonance IMAGING and diffusion TENSOR IMAGING Brain IMAGING Topographic organization
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Functional Spectral Analysis of Paleoclimatic Evolution in Lanzhou Area over the Last 15 ka 被引量:1
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作者 杨桂芳 殷鸿福 +1 位作者 李长安 陈中原 《Chinese Journal Of Geochemistry》 EI CAS 2003年第4期377-380,共4页
In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 conte... In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 content, the law of paleoclimatic evolution of the Hongzuisi section is obtained. There were climatic changes from 10 ka to about 0.1 ka over the last 15 ka. Among these cycles, the cycle of several ka is most remarkable. The result indicates that functional spectral analysis is helpful for paleoclimatic study, which can provide useful information about paleoclimatic reconstruction and future forecast. 展开更多
关键词 PALEOCLIMATIC EVOLUTION functional spectral analysis organic carbon ISOTOPE CAC03 content
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SYNTHESIS OF CATALYSIS BY THE FUNCTIONALIZATION OF SILICA AND ITS APPLICATIONS
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作者 Yasuhiko Kurusu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第1期1-12,共12页
Hybrid organic-inorganic silica materials containing organic functional groups have been preparedby the reaction of activated silica with a silane coupling reagent such as N-(2-aminoethyl)3-aminopropyltrimethoxysilane... Hybrid organic-inorganic silica materials containing organic functional groups have been preparedby the reaction of activated silica with a silane coupling reagent such as N-(2-aminoethyl)3-aminopropyltrimethoxysilane. The hybrid silica was further modified by organic compounds having abifunctional group. These modified hybrid silicas were used as catalysts for various nucleophilic reactions.And also, these were complexed with metallic ions for use as catalysts for oxygen oxidation of hydrocarbons. 展开更多
关键词 Organic-inorganic hybrid polymer functionalized silica Dioxygen oxidation of hydrocarbon Reaction with functionalized silica
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Application of radiation chemistry to the construction of functional organic materials
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作者 Tsuneki Ichikawa Hitoshi Koizumi +1 位作者 Takahide Kimura Tohru Shimizu 《辐射研究与辐射工艺学报》 CAS CSCD 北大核心 2005年第2期102-102,共1页
关键词 伽玛辐射 氮离子束 有机功能材料 辐射化学感应
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SYNTHESIS AND PHOTOELECTRIC PROPERTIES OF PERYLENE RED PIGMENTS
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作者 刘东志 刘广辰 齐翠娥 《Transactions of Tianjin University》 EI CAS 1997年第2期62-66,共5页
A series of N, N′ dialkyl (and aryl) perylene 3,4:9, 10 bis (dicarboximide) compounds were prepared and purified, and their photoelectric properties as organic photoconductors were explored. It is found that N, N′... A series of N, N′ dialkyl (and aryl) perylene 3,4:9, 10 bis (dicarboximide) compounds were prepared and purified, and their photoelectric properties as organic photoconductors were explored. It is found that N, N′ dimethyl perylene 3,4:9, 10 bis (dicarboximide) and perylene 3,4:9,10 tetracarboxylic acid bisbenzimidazole show excellent photoconductivities, their charge acceptance reaches 700 V and 485 V, and the photosensitivity is 45 lx·s and 10 lx·s with dark decays 70 and 60 V/s respectively. The introduction of chlorine atoms can improve their photoelectric properties. SEM analyses also show that the dispersion of pigment in OPC could affect its photosensitivity. 展开更多
关键词 organic photoconductor ELECTROPHOTOGRAPHY perylene derivatives functional dyes
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The Trace Elements are Bounded by Organic Functional Groups in Coal:A Studying Result Based on FTIR Analysis 被引量:5
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作者 YANG Jianye WANG Guangheng ZHANG Weiguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期154-165,共12页
The relationship between trace elements in coal and organic functional groups of coal, also some of aromatic structure, was investigated by using curve fitting of infrared spectra. Cluster analysis was also performed ... The relationship between trace elements in coal and organic functional groups of coal, also some of aromatic structure, was investigated by using curve fitting of infrared spectra. Cluster analysis was also performed according to the degree of affinity of organic groups to the trace elements. The results show that there is a possibility that trace elements, especially LREE, were bound to peripheral organic functional groups of middle rank coal macromolecule. The most possible functional group that binds trace element is the hydroxyl, and to the less degree, the asymmetric -CH3 and 〉CH2 stretching, -CH3 stretching, etc. The degree of affinity of trace elements to different functional groups varies. The tendency obeys the natural structural changing law of trace elements-- the periodic law. The deviation of some trace elements from this regular trend is attributed to the deviation of intrinsic "confusion degree" (conventional molar entropy) of the matter system of coal basin, which is affected by the inner and outer factors during the evolution. 展开更多
关键词 curve fitting organic functional groups in coal trace element periodic law of elements
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Clinical Study on Therapy of Clearing Hallow Viscera in Treating Critical Patients with Gastro-enteric Function Disorder 被引量:6
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作者 杨胜兰 李道本 《Chinese Journal of Integrated Traditional and Western Medicine》 2006年第2期122-125,共4页
Objective: To explore the clinical effect of therapy of clearing hallow viscera in treating critical patients with gastro-enteric function disorder (GEFD). Methods: Retrospective analysis was carried out on 96 cri... Objective: To explore the clinical effect of therapy of clearing hallow viscera in treating critical patients with gastro-enteric function disorder (GEFD). Methods: Retrospective analysis was carried out on 96 critical patients. They were 48 patients in the treated group treated with Dachengqi Decoction ( 大承气汤) and 48 patients in the control group treated with Western medicine for promoting gastric dynamic force. The recovery rate, recovery time of gastro-enteric function, incidence rate and fatality rate of multiple organ dysfunction syndrome (MODS), as well as the level of plasma endotoxin (ET) before and after treatment between the two groups were compared. Results: Comparison between the two groups in gastro-enteric function recovery rate (81.3% vs 45.8 %), functional disorder sustaining time in patients who got recovered (1.2± 0.3 daysvs4.0±1.1 days), incidence rate (29. 17% vs 52.08%) and fatality rate (28.57% vs 56.00%) of MODS all showed significant difference ( P〈0.05 or P〈0.01 ). The plasma level of ET after treatment in the treated group was significantly lower than that in the control group (P〈0.05). Conclusion: Therapy of clearing hallow viscera has a good effect in treating critical patients with gastro-enteric function disorder, and could reduce the incidence and fatality of MODS. 展开更多
关键词 therapy of clearing hallow viscera Dachengqi Decoction gastro-enteric function disorder multiple organ dysfunction syndrome
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The remarkable effect of organic salts on 1,3,5-trioxane synthesis 被引量:1
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作者 Liu-Yi Yin Yu-Feng Hu Hai-Yan Wang 《Petroleum Science》 SCIE CAS CSCD 2016年第4期770-775,共6页
The effects of organic salts on 1,3,5-trioxane synthesis were investigated through batch reaction and continuous production experiments. The organic salts used include sodium methanesulfonate(CH3NaO3S), sodium benze... The effects of organic salts on 1,3,5-trioxane synthesis were investigated through batch reaction and continuous production experiments. The organic salts used include sodium methanesulfonate(CH3NaO3S), sodium benzenesulfonate(C6H5NaO3S), sodium 4-methylbenzenesulfonate(C7H7NaO3S), and sodium 3-nitrobenzene sulfonate(C6H4NNaO5S). It was shown that the effects of organic salts on the yield of 1,3,5-trioxane in reaction solution and distillate follow the order CH3NaO3S /C6H5NaO3S/C7H7NaO3S/C6H4NNaO5S, which is inversely related to the charge density of the anions of the organic salts. In comparison with Cl–-based salts such as magnesium chloride, organic salts have the advantages of less formic acid generation and low corrosion. Studies on water activity revealed that the effect of organic salts on the activity of water was quite small at low concentration of organic salts. UV–visible spectroscopy and vapor–liquid equilibrium experiments were performed to uncover the mechanisms that govern such effects. The results showed that the effect of organic salts on the yield of 1,3,5-trioxane relies primarily on their ability to increase the catalytic activity of sulfuric acid and increase the relative volatilities of 1,3,5-trioxane and water and of 1,3,5-trioxane and oligomers. 展开更多
关键词 1 3 5-Trioxane Organic salt Salt effect Hammett function Relative volatility
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Prediction of Aqueous Solubility for 209 Polychlorinated Diphenyl Ethers from Molecular Structural Parameters by DFT Method 被引量:3
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作者 谢亚杰 柳红霞 +1 位作者 王遵尧 朱丽丹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第4期481-490,共10页
Optimized calculations of 209 polychlorinated diphenyl ethers (PCDEs) and diphenyl ethers were carried out at the B3LYP/6-31G^* level with the Gaussian 98 program. Based on the theoretical linear solvation energy r... Optimized calculations of 209 polychlorinated diphenyl ethers (PCDEs) and diphenyl ethers were carried out at the B3LYP/6-31G^* level with the Gaussian 98 program. Based on the theoretical linear solvation energy relationship (TLSER) model, the obtained structural parameters were taken as theoretical descriptors to establish the novel QSPR model for predicting aqueous solubility (-lgSw) of PCDEs. The model obtained in this work contains two variables: mean molecular polarizability (a) and the most positive partial charge on a hydrogen atom (qH^+), of which RE = 0.9606 and SD = 0.32. And the results of cross-validation test also show that the model exhibits optimum stability and better predictive power. Moreover, the predictive power of the new model is better than that of MCIs method. 展开更多
关键词 persistent organic pollutants (POPs) polychlorinated diphenyl ethers (PCDEs) aqueous solubility (-lgSw) quantitative structure-property relationship (QSPR) density functional theory (DFT) method
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Effects of spring fire and slope on the aboveground biomass, and organic C and N dynamics in a semi-arid grassland of northern China 被引量:1
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作者 ZHAO Xiang HU Shuya +4 位作者 DONG Jie REN Min ZHANG Xiaolin DONG Kuanhu WANG Changhui 《Journal of Arid Land》 SCIE CSCD 2019年第2期267-279,共13页
The aboveground primary production is a major source of carbon(C) and nitrogen(N) pool and plays an important role in regulating the response of ecosystem and nutrient cycling to natural and anthropogenic disturbances... The aboveground primary production is a major source of carbon(C) and nitrogen(N) pool and plays an important role in regulating the response of ecosystem and nutrient cycling to natural and anthropogenic disturbances. To explore the mechanisms underlying the effect of spring fire and topography on the aboveground biomass(AGB) and the soil C and N pool, we conducted a field experiment between April 2014 and August 2016 in a semi-arid grassland of northern China to examine the effects of slope and spring fire, and their potential interactions on the AGB and organic C and total N contents in different plant functional groups(C_3 grasses, C_4 grasses, forbs, Artemisia frigida plants, total grasses and total plants).The dynamics of AGB and the contents of organic C and N in the plants were examined in the burned and unburned plots on different slope positions(upper and lower). There were differences in the total AGB of all plants between the two slope positions. The AGB of grasses was higher on the lower slope than on the upper slope in July. On the lower slope, spring fire marginally or significantly increased the AGB of C_3 grasses, forbs, total grasses and total plants in June and August, but decreased the AGB of C_4 grasses and A.frigida plants from June to August. On the upper slope, however, spring fire significantly increased the AGB of forbs in June, the AGB of C_3 grasses and total grasses in July, and the AGB of forbs and C_4 grasses in August. Spring fire exhibited no significant effect on the total AGB of all plants on the lower and upper slopes in 2014 and 2015. In 2016, the total AGB in the burned plots showed a decreasing trend after fire burning compared with the unburned plots. The different plant functional groups had different responses to slope positions in terms of organic C and N contents in the plants. The lower and upper slopes differed with respect to the organic C and N contents of C_3 grasses, C_4 grasses, total grasses, forbs, A. frigida plants and total plants in different growing months. Slope position and spring fire significantly interacted to affect the AGB and organic C and N contents of C_4 grasses and A. frigida plants. We observed the AGB and organic C and N contents in the plants in a temporal synchronized pattern. Spring fire affected the functional AGB on different slope positions, likely by altering the organic C and N contents and, therefore,it is an important process for C and N cycling in the semi-arid natural grasslands. The findings of this study would facilitate the simulation of ecosystem C and N cycling in the semi-arid grasslands in northern China. 展开更多
关键词 ABOVEGROUND biomass plant functional group SPRING FIRE SLOPE position N CONTENT organic C CONTENT SEMI-ARID grassland
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Verify the Function of a Potential Growth-Regulating Gene in Marine Bivalve Using a Candidate Model Organism Mulinia lateralis 被引量:1
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作者 WANG Chen KONG Lingling +6 位作者 LIAN Shanshan YANG Zujing MENG Deting LI Moli ZHANG Xiangchao BAO Zhenmin HU Xiaoli 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期1012-1022,共11页
A better understanding of genetic bases of growth regulation is essential for bivalve breeding,which is helpful to improve the yield of the commercially important bivalves.While previous studies have identified some c... A better understanding of genetic bases of growth regulation is essential for bivalve breeding,which is helpful to improve the yield of the commercially important bivalves.While previous studies have identified some candidate genes accounting for variation in growth-related traits through genotype-phenotype association analyses,seldom of them have verified the functions of these putative,growth-related genes beyond the genomic level due to the difficulty of culturing commercial bivalves under laboratory conditions.Fortunately,dwarf surf clam Mulinia lateralis can serve as a model organism for studying marine bivalves given its short generation time,the feasibility of being grown under experimental conditions and the availability of genetic and biological information.Using dwarf surf clam as a model bivalve,we characterize E2F3,a gene that has been found to account for variation in growth in scallops by a previous genome-wide association study,and verify its function in growth regulation through RNA interference(RNAi)experiments.For the first time,E2F3 in dwarf surf clam,which is termed as MulE2F3,is characterized.The results reveal that dwarf surf clams with MulE2F3 knocked down exhibit a reduction in both shell size and soft-tissue weight,indicating the functions of MulE2F3 in positively regulating bivalve growth.More importantly,we demonstrate how dwarf surf clam can be used as a model organism to investigate gene functions in commercial bivalves,shedding light on genetic causes for variation in growth to enhance the efficiency of bivalve farming. 展开更多
关键词 growth-regulating gene FUNCTION marine bivalve model organism Mulinia lateralis
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A thioether-functionalized pyrene-based covalent organic framework anchoring ultrafine Au nanoparticles for efficient photocatalytic hydrogen generation 被引量:1
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作者 Zhiming Zhou Chuanbiao Bie +2 位作者 Peize Li Bien Tan Yan Shen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2699-2707,共9页
Covalent organic frameworks(COFs)have lately emerged as a blooming class of potential materials for photocatalytic water splitting because of their high crystallinity,huge surface areas,and structural versatility.Howe... Covalent organic frameworks(COFs)have lately emerged as a blooming class of potential materials for photocatalytic water splitting because of their high crystallinity,huge surface areas,and structural versatility.However,the photocatalytic performance for most pure COFs face some limitations factors,such as the significant recombination of photogenerated carriers and slow charge transfer.Herein,a novel thioether-functionalized pyrene-based COF(S_(4)-COF)was effectively produced and chosen as a support for the immobilization of ultrafine gold nanoparticles(Au NPs).S_(4)-COF photocatalyst with Au as cocatalyst demonstrates remarkable photocatalytic activity with a H_(2) generation rate of 1377μmol g^(−1) h^(−1) under visible light(>420 nm),which is ca.4.5-fold increase comparing to that of pure S_(4)-COF(302μmol g^(−1) h^(−1)).Au NPs anchored on S_(4)-COF possess an ultrafine size distribution ranging from 1.75 to 6.25 nm with an average size centered at 3.8 nm,which benefits from the coordination interaction between thioether groups and Au.Meanwhile,the produced Au@S_(4)-COF can generate a stable photocatalytic H_(2) generation during the four recycles and preserve its crystallinity structure after the stability testing.The Au NPs anchored on the S_(4)-COF photocatalyst can greatly accelerate the separation of photogenerated carriers and increase charge transfer because of the combined function of Au NPs and thioether groups.Such a method can not only prevent the aggregation of Au NPs onto thioether-containing COFs to achieve long-term photostability but also allow uniform dispersion for an ordered structure of photocatalysts.This work provides a rational strategy for designing and preparing COF-based photocatalysts for solar-driven H_(2) production. 展开更多
关键词 Photocatalysis Covalent organic framework Thioether functionalization Gold nanoparticle Coordination interaction Photogenerated carrier separation
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Does shifting to professional emergency department staffing affect the decision for chest radiography?
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作者 Marin Pavlov Lucija Klobucar +2 位作者 Iva Klobučar Kristinazgela Vesna Degoricija 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第2期87-92,共6页
BACKGROUND: The study aims to determine whether shifting to professional emergency department(ED) teams leads to a higher rate of radiologic workup.METHODS: We retrospectively analyzed a total of 2,000 patients presen... BACKGROUND: The study aims to determine whether shifting to professional emergency department(ED) teams leads to a higher rate of radiologic workup.METHODS: We retrospectively analyzed a total of 2,000 patients presenting to the ED of a tertiary teaching hospital in two time periods: group 1(G1) comprised 1,000 consecutive patients enrolled from December 21, 2012 to January 5, 2013(all patients were examined by an internal medicine specialist);group 2(G2) comprised 1,000 consecutive patients enrolled from December 21, 2018 to January 3, 2019(all patients were examined by an emergency physician).RESULTS: The chest X-ray(CXR) was performed in 40.6% of all patients. There was no difference in the frequency of CXR(38.9% in G1 vs. 42.3% in G2, P=0.152). More CXRs were performed in G2 patients older than 65 years, in female patients older than 65 years, in patients presenting during the evening and night shifts or off-hours, in patients with a history of malignancy, in patients with gastrointestinal bleeding, and in patients with bradycardia, but fewer in patients presenting with arrhythmia. No difference in the rates of pathological CXR was found(47.3% in G1 vs. 52.2% in G2, P=0.186). Compared with G2, higher sensitivity and specificity were obtained for the binary logistic regression model predicting pathological findings in G1.CONCLUSIONS: Shifting to professional ED teams does not increase radiologic workup. By implementing deliberate usage of ultrasound, some self-governing procedures, case-oriented investigations, and center-specific recommendations, unnecessary radiologic workup can be avoided. Professional ED teams could lead to a higher standard of emergency care. 展开更多
关键词 Chest radiography Emergency department Emergency physicians Healthcare organization
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The Function,Future and Support Elements of Farmer Cooperative Economy Organization
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作者 Jing GAO Peng XIE 《Asian Agricultural Research》 2014年第5期105-108,共4页
The nature of farmer cooperative economy organization( known as FCEO) determines the fact that the economic effects of farmer cooperative economy organization are as important as its social effects. Many experts,howev... The nature of farmer cooperative economy organization( known as FCEO) determines the fact that the economic effects of farmer cooperative economy organization are as important as its social effects. Many experts,however,now would only focus on its economic function, and either neglect or weaken its social influence. Therefore,this paper introduces the theoretical foundation of the farmer cooperative economy organization,and studies the nature of cooperative economics. Based on those typical cases,the future of cooperative organization and four supporting elements were put forward in this paper. 展开更多
关键词 FARMER COOPERATIVE ECONOMY ORGANIZATION Function S
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The influence of prolapse surgery on sexual activity of women
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作者 Linde T. van Genugten Paul J. Q. van der Linden 《Open Journal of Obstetrics and Gynecology》 2014年第3期158-164,共7页
Aims: A prospective study to assess sexual activity in patients with pelvic organ prolapse (POP) and evaluate changes in sexual functioning after surgery. Secondary outcomes were quality of life and anatomical results... Aims: A prospective study to assess sexual activity in patients with pelvic organ prolapse (POP) and evaluate changes in sexual functioning after surgery. Secondary outcomes were quality of life and anatomical results. Methods: Patients completed the validated Leiden Questionnaire (LQ) and the short form 36 (SF-36) pre- and two months postoperatively. SPSS 19.0 was used for statistical analysis. Results: 74 patients (average age 61.5 years) were approached, of whom 33.8% were sexually inactive due to other reasons than POP. 23 patients (average age 56.7 years) were included for further analysis. Postoperatively we found a significant improvement for orgasm during intercourse. The remaining domains didn’t change significantly. A trend is noted, indicating that sexual activity stayed unchanged in 82.6% of patients. Dyspareunia improved in 47.8% of patients, lubrication in 34.8% and sexual satisfaction in 40%. Quality of life improved in 73.9%. We found a significant improvement in POP grading. Conclusion: More than a third of the patients presenting with POP are not sexually active due to other reasons than POP. POP surgery appears to improve lubrication, dyspareunia, sexual satisfaction and orgasm during intercourse in a considerable part of patients. Furthermore, there’s no negative influence on sexual activity. POP surgery improves quality of life in the majority of patients. 展开更多
关键词 Sexual Activity Sexual FUNCTIONING PELVIC ORGAN PROLAPSE Surgery LEIDEN QUESTIONNAIRE
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Biological Concept of Bacterial Pathogenicity (Theoretical Review)
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作者 Yurii V. Ezepchuk 《Advances in Microbiology》 2017年第7期535-544,共10页
Biological nature of the bacterial pathogenicity phenomenon is based on the interaction of prokaryotic and eukaryotic organisms. The phenomenon is the poly-functional biological potency of germs that are realized by f... Biological nature of the bacterial pathogenicity phenomenon is based on the interaction of prokaryotic and eukaryotic organisms. The phenomenon is the poly-functional biological potency of germs that are realized by factors (determinants) of pathogenicity. Some fundamental biological functions are responsible for bacterial pathogenicity in a multi-cellular host organism: the adhesive function, the function of invasion and penetration into the cell, the function of evasion of host defense, and the damage function. The action of adhesion, invasion and evasionis directed to towards establishing an ecological niche in multi-cellular host while the aim of the damaging function is destruction of the environment. 展开更多
关键词 Bacterial PATHOGENICITY Biological Function “Pathogenicity Islands” INFECTIOUS Diseases PROKARYOTIC and EUKARYOTIC ORGANISMS
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Substituent Effects on the Photocatalytic Properties of a Symmetric Covalent Organic Framework
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作者 Ting-Ting Liu Xin-Ping Wu Xue-Qing Gong 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第4期647-654,I0062-I0085,I0150,共33页
Symmetric covalent organic framework(COF)photocatalysts generally suffer from inefficient charge separation and short-lived photoexcited states.By performing density functional theory(DFT)and time-dependent density fu... Symmetric covalent organic framework(COF)photocatalysts generally suffer from inefficient charge separation and short-lived photoexcited states.By performing density functional theory(DFT)and time-dependent density functional theory(TDDFT)calculations,we find that partial substitution with one or two substituents(N or NH_(2))in the linkage of the representative symmetric COF(N_(0)-COF)gives rise to the separation of charge carriers in the resulting COFs(i.e.,N_(1)-COF,N_(2)-COF,(NH_(2))1-N_(0)-COF,and(NH_(2))2-N_(0)-COF).Moreover,we also find that the energy levels of the highest occupied crystal orbital(HOCO)and the lowest unoccupied crystal orbital(LUCO)of the N_(0)-COF can shift away from or toward the vacuum level,depending on the electron-withdrawing or electron-donating characters of the substituent.Therefore,we propose that partial substitution with carefully chosen electron-withdrawing or electron-donating substituents in the linkages of symmetric COFs can lead to efficient charge separation as well as appropriate HOCO and LUCO positions of the generated COFs for specific photocatalytic reactions.The proposed rule can be utilized to further boost the photocatalytic performance of many symmetric COFs. 展开更多
关键词 Covalent organic framework PHOTOCATALYSIS Electronic structure Charge separation Density functional theory calculation
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Species,growth form,and biogeographic diversity of summit vegetation along an elevation gradient in the tropical Andes:a baseline for climate change monitoring
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作者 Luis D.LLAMBI Luis E.GAMEZ +6 位作者 Roxibell PELAYO Carmen J.AZOCAR Jesus E.TORRES Nelson J.MARQUEZ Monica B.BERDUGO Francisco CUESTA Lirey A.RAMIREZ 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3441-3457,共17页
Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species compositio... Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species composition,richness and community structure along tropical alpine altitudinal gradients is of primary importance,both the functional and historical/biogeographic dimensions of vegetation diversity remain largely unexplored.We used Generalized Linear Models and multivariate analyses to assess changes in species,growth forms,and biogeographic groups richness and abundance,in response to habitat variables along an elevation gradient in seven summits(3800 to 4600 m asl)in the Venezuelan Andes,studied using the standardized approach of the GLORIA-Andes monitoring network.The habitat variables assessed were soil temperature(-10 cm),soil organic matter,slope inclination,and substrate cover.We found 113 species,representing72 genera,32 families,13 growth forms,and seven biogeographic origins,that included 25%of endemic elements.We observed richer vegetation,both in terms of species and growth forms,in summits with higher soil temperatures and higher SOM content,as well as higher biogeographic origin richness with increasing soil temperatures.The presence of holarctic elements increased toward higher elevations,while the occurrence of austral antarctic elements increased toward lower elevations.Our results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine environments.These findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses,in contrast with more traditional approaches,based only on taxonomic species diversity. 展开更多
关键词 Alpine vegetation BIOGEOGRAPHY Elevation gradient functional diversity Páramo Soil organic matter Temperature Tropical Andes
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