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SOME INEQUALITIES ABOUT DUAL MIXED VOLUMES OF STAR BODIES 被引量:5
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作者 李小燕 冷岗松 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期505-510,共6页
The authors establish some inequalities about the dual mixed volumes of star bodies in Rn. These inequalities are the analogue in the Brunn-Minkowski theory of the inequalities of Marcus-Lopes and Bergstrom about symm... The authors establish some inequalities about the dual mixed volumes of star bodies in Rn. These inequalities are the analogue in the Brunn-Minkowski theory of the inequalities of Marcus-Lopes and Bergstrom about symmetric functions of positive reals. 展开更多
关键词 Brunn-Minkowski theory star bodies dual mixed volumes Aleksandrov Fenchel inequality.
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Lower-Dimensional Volumes and Kastler-Kalau-Walze Type Theorem for Manifolds with Boundary 被引量:4
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作者 王勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期38-42,共5页
In this paper,we define lower-dimensional volumes of spin manifolds with boundary.We compute thelower-dimensional volume Vol^((2,2)) for 5-dimensional and 6-dimensional spin manifolds with boundary and we also getthe ... In this paper,we define lower-dimensional volumes of spin manifolds with boundary.We compute thelower-dimensional volume Vol^((2,2)) for 5-dimensional and 6-dimensional spin manifolds with boundary and we also getthe Kastler-Kalau-Walze type theorem in this case. 展开更多
关键词 lower-dimensional volumes noncommutative residue for manifolds with boundary gravitationalaction for manifolds with boundary
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Application of prolonging small feeding volumes early in life to prevent of necrotizing enterocolitis in very low birth weight preterm infants 被引量:3
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作者 Qiu-fang Li Hua Wang +2 位作者 Dan Liu Yi Tang Xin-fen Xu 《International Journal of Nursing Sciences》 2016年第1期45-49,共5页
Objective:To study the effects of prolonging small feeding volumes early in life on the incidence of necrotizing enterocolitis(NEC)in very low birth weight(VLBW)preterm infants.Methods:A total of 128 VLBW infants who ... Objective:To study the effects of prolonging small feeding volumes early in life on the incidence of necrotizing enterocolitis(NEC)in very low birth weight(VLBW)preterm infants.Methods:A total of 128 VLBW infants who could not be breastfed were assigned into the experimental group(63 cases)and the control group(65 cases)using a random number table.The experiment group was fed 12 mL/(kg·d)on day 1 which was increased to 24 mL/(kg·d)for the first 10 study days.The control group was fed 12 mL/(kg·d)for the first 14e48 hours.Then,the feeding volume increased by 24-36 mL/(kg·d)up to 140e160 mL/(kg·d)and maintained until the 10th day after birth.The incidence of feeding intolerance and NEC,duration of hospitalization,time to full enteral feedings,incidence of intrahepatic cholestasis,and the levels of gastrin and motilin in serum were assessed.Results:The incidence of feeding intolerance was significantly lower in the experimental group compared with the control group(15.87% vs.33.84%).There was a significant reduction in the incidence of NEC between the experimental and control groups(7.9% vs.16% in the control group).Conclusion:A protocol that prolongs small feeding volumes early in life can reduce the incidence and severity of NEC,but still warrants further study. 展开更多
关键词 Infant formula Necrotizing enterocolitis Preterm infant Prolonging small feeding volumes Very low birth weight infant
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Densities and excess molar volumes of mixtures containing diesel,biodiesel and alkanols at temperatures from 288.15 to 313.15 K
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作者 Sunita Malik Poonam Jangra Darolia +1 位作者 S.K.Garg V.K.Sharma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第6期198-207,共10页
The present work is focusing on the synthesization and physico-chemical properties of Jatropha curcas biodiesel with diesel and alcohols.The densities of binary diesel(2)+1-alkanols(C_(3) or C_(4))(3)and ternary Jatro... The present work is focusing on the synthesization and physico-chemical properties of Jatropha curcas biodiesel with diesel and alcohols.The densities of binary diesel(2)+1-alkanols(C_(3) or C_(4))(3)and ternary Jatropha curcas biodiesel(1)+diesel(2)+1-alkanols(C_(3)or C_(4))(3)blends have been reported over full range of composition at temperatures within range 288.15 to 313.15 K.Also densities of Jatropha curcas biodiesel(1)+diesel or 1-alkanols(C_(3) or C_(4))(2)blends have been measured at 313.15 K.Excess molar volumes,V^E,V^E_(123)of binary and ternary blends were calculated from the measured data and the derived properties were correlated to composition using Redlich-Kister equation.A reasonable agreement was found between the measured and estimated values.Further,densities and excess molar volumes data were reasoned to discuss molecular interactions taking into consideration effect of composition and temperature. 展开更多
关键词 Jatropha curcas biodiesel DIESEL ALCOHOLS Blends Density Excess molar volumes
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Effects of smoking on cerebral and ventricular volumes in healthy males
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作者 Hyun-Jun Kim Mi-Hyun Choi +9 位作者 Beob-Yi Lee Su-Jeong Lee Jae-Woong Yang Ji-Hye Kim Jin-Seung Choi Dong-Won Kang Jang-Yeon Park Jae-Hoon Jun Gye-Rae Tack Soon-Cheol Chung 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第1期72-75,共4页
Previous studies have reported decreased cerebral volume as a result of smoking. However, little is known about accompanying changes in ventricular volume for healthy subjects who smoke, although ventricular volume is... Previous studies have reported decreased cerebral volume as a result of smoking. However, little is known about accompanying changes in ventricular volume for healthy subjects who smoke, although ventricular volume is increased in patients with multiple sclerosis who smoke. The present study analyzed whether cerebral volume decreased with smoking through the use of magnetic resonance imaging. In addition, accompanying changes in ventricular volume that resulted from decreased cerebral volume and smoking were analyzed in healthy subjects. When multivariate analysis of covariance was performed by integrating the 2 age groups, aged 20-28 years and 40-49 years, with statistical significance, results showed that cerebral volume of smokers was smaller and ventricular volume was greater compared with the non-smokers. These findings suggest that ventricular volume changes could be utilized to characterize the effects of smoking. 展开更多
关键词 SMOKING cerebral and ventricular volumes magnetic resonance imaging
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Hippocampus and amygdala volumes in patients with vaginismus
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作者 Murad Atmaca Sema Baykara +3 位作者 Omer Ozer Sevda Korkmaz Unsal Akaslan Hanefi Yildirim 《World Journal of Psychiatry》 SCIE 2016年第2期221-225,共5页
AIM: To compare hippocampus and amygdala volumes of patients with vaginismus with those of healthy control subjects.METHODS: Magnetic resonance imaging was performed on ten patients with vaginismus and ten control sub... AIM: To compare hippocampus and amygdala volumes of patients with vaginismus with those of healthy control subjects.METHODS: Magnetic resonance imaging was performed on ten patients with vaginismus and ten control subjects matched for age and gender. Volumes of the hippocampus and amygdala were blindly measured. RESULTS: We found that the mean right amygdala volume of patients with vaginismus were smaller than that of the healthy controls. With regard to hippocampus volumes, the mean left and right hippocampus volumes were smaller than those of the healthy controls. CONCLUSION: Our present findings suggest that there have been hippocampus and amygdala structural abnormalities in patients with vaginismus. These changes provide the notion that vaginismus may be a fear-related condition. 展开更多
关键词 VAGINISMUS HIPPOCAMPUS AMYGDALA volumes PATIENTS
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Comparison between Neural Network and Adaptive Neuro-Fuzzy Inference System for Forecasting Chaotic Traffic Volumes
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作者 Jiin-Po Yeh Yu-Chen Chang 《Journal of Intelligent Learning Systems and Applications》 2012年第4期247-254,共8页
This paper applies both the neural network and adaptive neuro-fuzzy inference system for forecasting short-term chaotic traffic volumes and compares the results. The architecture of the neural network consists of the ... This paper applies both the neural network and adaptive neuro-fuzzy inference system for forecasting short-term chaotic traffic volumes and compares the results. The architecture of the neural network consists of the input vector, one hidden layer and output layer. Bayesian regularization is employed to obtain the effective number of neurons in the hidden layer. The input variables and target of the adaptive neuro-fuzzy inference system are the same as those of the neural network. The data clustering technique is used to group data points so that the membership functions will be more tailored to the input data, which in turn greatly reduces the number of fuzzy rules. Numerical results indicate that these two models have almost the same accuracy, while the adaptive neuro-fuzzy inference system takes more time to train. It is also shown that although the effective number of neurons in the hidden layer is less than half the number of the input elements, the neural network can have satisfactory performance. 展开更多
关键词 NEURAL Network Adaptive NEURO-FUZZY INFERENCE System CHAOTIC TRAFFIC volumes State Space Reconstruction
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Systematic Evaluation of Current Possibilities to Determine Left Ventricular Volumes by Echocardiography in Patients after Myocardial Infarction
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作者 Stephan Stoebe Adrienn Tarr +2 位作者 Tudor Trache Jens-Gerrit Kluge Dietrich Pfeiffer 《Open Journal of Medical Imaging》 2012年第2期68-75,共8页
Purpose: The aim of the present study was to evaluate the diagnostic accuracy for quantification of left ventricular (LV) volumes and LV ejection fraction (LVEF) with current echocardiographic methods of planimetry fo... Purpose: The aim of the present study was to evaluate the diagnostic accuracy for quantification of left ventricular (LV) volumes and LV ejection fraction (LVEF) with current echocardiographic methods of planimetry for analysis of LV remodeling after myocardial infarction in daily clinical routine. Methods: 26 patients were investigated directly after interventional therapy at hospital pre-discharge and at 6 month follow-up. Standardized 2D transthoracic native and contrast echocardiography were performed in all patients. Due to methodological aspects the results of LV volumes and LVEF using native echocardiography were compared to the results of LV opacification (LVO) imaging for analysis in mono-, bi- and triplane data sets using the Simpson’s rule. In addition corresponding multidimensional data sets were analyzed. Results: The assessment of LV volumes and LVEF is more accurate with contrast echocardiography. The comparison of LV volumes and LVEF shows significant increases using contrast echocardiography (p < 0.001). Larger left ventricular end-diastolic volumes (LVEDV) are measured at follow up (p < 0.05). Significant differences (p < 0.001) are found for the determination of LVEDV and LVEF relating to apical mono-, bi-, tri- and multiplane data sets. Standard deviations of the triplane approach, however, are significantly lower than using other modalities. Conclusion: Depending on the localization of the myocardial infarction LV volumes and LVEF are less reliably evaluated using the mono- or biplane approach. According to standardization and simultaneous acquisition of all LV wall segments the triplane approach is currently the best approach to determine LV systolic function. In addition, contrast echocardiography is indicated to improve endocardial border delineation in patients using the triplane or multiplane approach. To our knowledge the present study is the first systematic evaluation of all current possibilities for determination of LV volumes and LVEF by native and contrast echocardiography. 展开更多
关键词 Contrast ECHOCARDIOGRAPHY LEFT VENTRICULAR SYSTOLIC Function LEFT VENTRICULAR volumes Remodeling Myocardial INFARCTION LVO Imaging
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A ROBUST FLOW CALCULATION TECHNIQUE WITH MULTIPLE FINITE CONTROL VOLUMES
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作者 E.Morishita 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1991年第2期121-125,共5页
The control volume method gives the forces which act on the system, but not necessarily the wall pressure of the system. The author has made an attempt to develop a control volume method which makes it possible to obt... The control volume method gives the forces which act on the system, but not necessarily the wall pressure of the system. The author has made an attempt to develop a control volume method which makes it possible to obtain the wall pressure of the control volume. The 2-D inviscid incompressible steady duct flow is considered. The conservation equations in integral form are discretized for a control volume. The circulation along the control surface is expressed as a nonlinear function of the vertical velocity component at the inlet and is set equal to zero for the inviscid flow. The equation is solved by the Newton method, and the other aerodynamic properties can be obtained. The calculated results have been compared to the experiment and the agreement has been found fairly satisfactory. 展开更多
关键词 A ROBUST FLOW CALCULATION TECHNIQUE WITH MULTIPLE FINITE CONTROL volumes
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Equal Volumes of Sand and Gravel Concrete Mix Ratios in Cameroon and Its Effect on Concrete Compressive Strength
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作者 Patrick Bame Che Yamb Bell Emmanuel Ndigui Billong 《World Journal of Engineering and Technology》 2022年第3期539-549,共11页
In recent years, the rationalization of concrete mix ratios which batches equal volumes of sand and gravel in building projects has been gaining grounds in the Cameroon construction industry. The main objective of thi... In recent years, the rationalization of concrete mix ratios which batches equal volumes of sand and gravel in building projects has been gaining grounds in the Cameroon construction industry. The main objective of this study is therefore to investigate if the concrete produced with rationalized mix ratio can be adopted as conventional mix ratio in terms of minimum required compression strength of concrete for buildings. Specifically this work compared the conventional mix ratio of 350 kg of cement: 400 liters of sand: 800 liters of gravel for a cubic meter and the rationalized batch of 350 kg of cement: 600 liters of sand: 600 liters of 5/15 gravel, 15/25 gravel and a combination of 5/15 + 15/25 gravel. Average compressive tests’results for both the conventional and the rationalized mix ratios were found to meet the minimum compressive strength of 65% at 7 days, 90% at 14 days and 99% at 28 days for gravel size combination 5/15 + 15/25. Single size gravel of 5/15 and 15/25 did not meet the minimum required compressive strength of 20 N/mm<sup>2</sup> for the rationalized mix ratio at 28 days curing based on the minimum compressive strength required, this study arrives at the conclusion that the equal volumes of sand and gravel mix ratio of 350 kg/m<sup>3</sup> of cement: 600 liters of sand: 600 liters of gravel mix ratio can be adopted as a conventional concrete mix ratio for gravel size 5/15 + 15/25. 展开更多
关键词 Conventional Concrete Rationalized Concrete Mix Ratio Compressive Strength Equal volumes of Sand and Gravel
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Belly fat is Linked with lower volumes of gray matter
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作者 张蕊 《新世纪智能》 2019年第20期28-30,共3页
Belly fat has long been thought to be particularly bad for your heart, but now, a new study adds more evidence to the idea that it may also be bad for your brain. The study, from the United Kingdom, found that people ... Belly fat has long been thought to be particularly bad for your heart, but now, a new study adds more evidence to the idea that it may also be bad for your brain. The study, from the United Kingdom, found that people who were obese and had a high waist-to-hip ratio (a measure of belly fat) had slightly lower brain volumes, on average, compared with people who were a healthy weight. Specifically, belly fat was linked with lower volumes of gray matter, the brain tissue that contains nerve cells. 展开更多
关键词 Belly FAT LOWER volumes GRAY MATTER
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Quantification of irrigation water transport processes in ZiZiphus jujuba garden using water stable isotopes
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作者 ZHONG Xiaofei ZHANG Mingjun +3 位作者 CHE Cunwei LIU Zechen LI Beibei ZHANG Yuanyuan 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3263-3274,共12页
ZiZiphus jujuba,which is native to China,has become one of the main crops widely planted in the western Loess Plateau because of its drought and flood-tolerance,adaptability,and higher nutritional value of the fruit.T... ZiZiphus jujuba,which is native to China,has become one of the main crops widely planted in the western Loess Plateau because of its drought and flood-tolerance,adaptability,and higher nutritional value of the fruit.The irrigation water infiltration in Z.jujuba gardens is complex,and understanding its mechanisms is essential for efficient water use and sustainable agriculture.This knowledge helps ensure the long-term success of jujuba cultivation.This paper describes a field experiment that investigates the infiltration process of irrigation water from Z.jujuba garden and quantifies the contribution of irrigation water to soil water at different depths using the MixSIAR model.According to the FC(Field water holding Capacity)of Z.jujuba,irrigation experiments with three volumes of 80%FC,60%FC,and 40%FC are set up in this study.The study finds that water retention is better in Z.jujuba garden soils with a higher proportion of coarse gravel in the soil particle composition.Soil water content exhibits a gradient change after irrigation,with deeper wetting front transport depth observed with increased irrigation water.Additionally,there is correlation between soil temperature and soil water content.The soil water in Z.jujuba garden generally exhibits a preferential flow signal in the 0-40 cm range.Below 40 cm,a piston flow pattern dominates.The rate of soil water infiltration increases with the amount of irrigation water.In the 0-40 cm range of the soil vertical profile,irrigation water was the main contributor to soil water.Z.jujuba demonstrated flexibility in water uptake,primarily absorbing soil water at depths of 0-40 cm.For optimal growth of Z.jujuba at this stage,40%FC irrigation is recommended.The results are expected to be valuable future irrigation practices and land use planning for Z.jujuba garden in arid zones,supporting sustainable agricultural development and water management. 展开更多
关键词 Water stable isotopes Different irrigation volumes ZiZiphus jujuba Irrigation water infiltration process MixSIAR model
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Analysis of Pedestrian Facilities in CBD Area of Pabna Municipality, Bangladesh
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作者 Md. Saiful Islam Md. Sohel Rana 《Journal of Civil Engineering and Architecture》 2017年第11期1025-1037,共13页
Pabna is one the most densely populated town with poor transport infrastructure in Bangladesh. Here huge pedestriangathers in roads and intersections in CBD (Central Business District) area mainly for commercial and... Pabna is one the most densely populated town with poor transport infrastructure in Bangladesh. Here huge pedestriangathers in roads and intersections in CBD (Central Business District) area mainly for commercial and business purposes. At present,pedestrian facilities are one of the greatest challenges in terms of traffic and safety for the urban dwellers. The footpath, zebra rossing,road intersection, walkways, parking and other facilities are the major part of road transportation system as well as pedestrianfacilities and people have to pass walking distance to reach their destinations, before and after use of transport mode. For instance,this paper tries to emphasize the problems of pedestrian facilities and to explore the qualitative level of comfort for the pedestrians ofthree selected intersections namely Traffic More, Indra More and Nimtola More in CBD area of Pabna Municipality through primaryand secondary data. However, about 60% trips are making on foot every day, but the pedestrians are facing many problems whileusing the walkways. Pedestrian crossing behaviors were also observed by using pedestrian volume survey and the survey exploresthat pedestrian crossing rate at these intersections is about 5,000 to 7,000 per hour at a peak period and average 15% to 25% illegalcrossing occurs at those intersections. The physical observation and data from the questionnaire survey also indicate that informalbusiness on the footpath, illegal parking, illegal vendor on walkways, physical obstacle, poor lighting facilities and geometricproblem of the road intersection makes uncomfortable situations for the pedestrian day by day. 展开更多
关键词 PEDESTRIAN facilities TRAFFIC congestion PEDESTRIAN crossing CBD area TRAFFIC volumes.
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Shrinkage and Expansive Strain of Concrete with Fly Ash and Expansive Agent 被引量:15
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作者 高培伟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第1期150-153,共4页
The effects of fly ash and MgO-type expansive agent on the shrinkage and expan-sive strain of concrete with high magnesia cement were investigated. The results show that high volumes of fly ash may reduce the shrinkag... The effects of fly ash and MgO-type expansive agent on the shrinkage and expan-sive strain of concrete with high magnesia cement were investigated. The results show that high volumes of fly ash may reduce the shrinkage strain of concrete and inhibit the expansive strain of concrete with MgO-type expansive agent, but can not eliminate the shrinkage of concrete. MgO-type expansive agent may produce expansive strain and compensate the shrinkage strain of concrete, re-lieve the cracking risk, but the hydration product of magnesia tends to get together in paste and pro-duce expansive cracking of concrete with high magnesia content according to SEM observation. 展开更多
关键词 high volumes of fly ash MgO-bearing expansive agent high magnesia cement volume stability
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Volume of unit ball in an n-dimensional normed space and its asymptotic properties 被引量:3
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作者 黄智悦 何斌吾 《Journal of Shanghai University(English Edition)》 CAS 2008年第2期107-109,共3页
Let Bp^n={x∈R^b|‖x‖p≤1} be the unit ball of p norm in the n-dimensional normed space εp&n.The formula for the volume of Bp^n was obtained and its asymptotic properties were found out as n→∞and p→∞.
关键词 unit ball normed space volumes gamma function asymptotic properties.
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Voxel-based magnetic resonance imaging investigation of poor and preserved clinical insight in people with schizophrenia 被引量:3
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作者 Adegboyega Sapara Dominic H Ffytche +2 位作者 Michael A Cooke Steven CR Williams Veena Kumari 《World Journal of Psychiatry》 SCIE 2016年第3期311-321,共11页
AIM To define regional grey-matter abnormalities in schizophrenia patients with poor insight(Insight-),relative to patients with preserved clinical insight(Insight+),and healthy controls.METHODS Forty stable schizophr... AIM To define regional grey-matter abnormalities in schizophrenia patients with poor insight(Insight-),relative to patients with preserved clinical insight(Insight+),and healthy controls.METHODS Forty stable schizophrenia outpatients(20 Insight-and 20 Insight+) and 20 healthy controls underwent whole brain magnetic resonance imaging(MRI).Insight in all patients was assessed using the Birchwood Insight Scale(BIS;a self-report measure).The two patient groups were preselected to match on most clinical and demographic parameters but,by design,they had markedly distinct BIS scores.Voxel-based morphometry employed in SPM8 was used to examine group differences in grey matter volumes across the whole brain.RESULTS The three participant groups were comparable in age [F(2,57) = 0.34,P = 0.71] and the patient groups did not differ in age at illness onset [t(38) = 0.87,P = 0.39].Insight-and Insight+ patient groups also did not differ in symptoms on the Positive and Negative Syndromes scale(PANSS):Positive symptoms [t(38) = 0.58,P = 0.57],negative symptoms [t(38) = 0.61,P = 0.55],general psychopathology [t(38) = 1.30,P = 0.20] and total PANSS scores [t(38) = 0.21,P = 0.84].The two patient groups,as expected,varied significantly in the level of BIS-assessed insight [t(38) = 12.11,P < 0.001].MRI results revealed lower fronto-temporal,parahippocampal,occipital and cerebellar grey matter volumes in Insightpatients,relative to Insight+ patients and healthy controls(for all clusters,family-wise error corrected P < 0.05).Insight+ patient and healthy controls did not differ significantly(P > 0.20) from each other.CONCLUSION Our findings demonstrate a clear association between poor clinical insight and smaller fronto-temporal,occipital and cerebellar grey matter volumes in stable long-term schizophrenia patients. 展开更多
关键词 PSYCHOSIS INSIGHT Grey matter volumes Fronto-temporal Neural networks Birchwood INSIGHT scale
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Cardiac remodeling as a consequence of atrial fibrillation: An anatomical study of perfusion-fixed human heart specimens 被引量:1
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作者 Christopher D Rolfes Stephen A Howard +1 位作者 Ryan P Golf Paul A Iaizzo 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2011年第3期141-146,共6页
Background Atrial fibrillation (AF) causes a continuum of atrial anatomical remodeling. Methods Using a library of perfusion-fixed human hearts, specimens with AF were compared to controls. During this preliminary a... Background Atrial fibrillation (AF) causes a continuum of atrial anatomical remodeling. Methods Using a library of perfusion-fixed human hearts, specimens with AF were compared to controls. During this preliminary assessment study, direct measurements were taken of atrial volume, pulmonary vein (PV) circumference, and left atrial (LA) wall thicknesses. Results Hearts with AF typically had larger atrial volumes, as well as a much larger variation in volume compared to controls (range of 59.6-227.1 mL in AF hearts compared to 65.1-115.9 mL in controls). For all hearts, right PVs were larger than left PVs (mean: 171.4 ± 84.6 mm^2 for right and 1182 ± 50.1 mm^2 for left, P 〈 0.005). LA wall thicknesses ranged from 0.7 mm to 3.1 mm for both AF and control hearts. Conclusions Hearts with AF had a large range of sizes which is consistent with the progression of atrial remodeling during AF. The large range of thicknesses will influence the amount of energy needed to create transmural lesions during ablation procedures. 展开更多
关键词 left atrial dimensions volumes pulmonary vein ostia atrial fibrillation
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Colonoscopy procedural volume increases adenoma and polyp detection rates in gastroenterology trainees 被引量:1
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作者 Emad Qayed Ravi Vora +1 位作者 Sara Levy Roberd M Bostick 《World Journal of Gastrointestinal Endoscopy》 CAS 2017年第11期540-551,共12页
AIM To investigate changes in polyp detection throughout fellowship training, and estimate colonoscopy volume required to achieve the adenoma detection rate(ADRs) and polyp detection rate(PDRs) of attending gastroente... AIM To investigate changes in polyp detection throughout fellowship training, and estimate colonoscopy volume required to achieve the adenoma detection rate(ADRs) and polyp detection rate(PDRs) of attending gastroenterologists.METHODS We reviewed colonoscopies from July 1, 2009 to June 30, 2014. Fellows' procedural logs were used to retrieve colonoscopy procedural volumes, and these were treated as the time variable. Findings from screening colonoscopies were used to calculate colonoscopy outcomes for each fellow for the prior 50 colonoscopies at each time point. ADR and PDR were plotted against colonoscopy procedural volumes to produce individual longitudinal graphs. Repeated measures linear mixed effects models were used to study the change of ADR and PDR with increasing procedural volume.RESULTS During the study period, 12 fellows completed full three years of training and were included in the analysis. The average ADR and PDR were, respectively, 31.5% and 41.9% for all fellows, and 28.9% and 38.2% for attendings alone. There was a statistically significant increase in ADR with increasing procedural volume(1.8%/100 colonoscopies, P = 0.002). Similarly, PDR increased 2.8%/100 colonoscopies(P = 0.0001), while there was no significant change in advanced ADR(0.04%/100 colonoscopies, P = 0.92). The ADR increase was limited to the right side of the colon, while the PDR increased in both the right and left colon. The adenoma per colon and polyp per colon also increased throughout training. Fellows reached the attendings' ADR and PDR after 265 and 292 colonoscopies, respectively.CONCLUSION We found that the ADR and PDR increase with increasing colonoscopy volume throughout fellowship. Our findings support recent recommendations of ≥ 275 colonoscopies for colonoscopy credentialing. 展开更多
关键词 Screening colonoscopy Colorectal cancer Polyp detection rate Colonoscopy volumes Adenoma detection rate Gastroenterology training
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Numerical Study of Natural Convection in an Inclined Porous Cavity 被引量:1
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作者 Saad Adjal Sabiha Aklouche-Benouaguef Belkacem Zeghmati 《Fluid Dynamics & Materials Processing》 EI 2022年第5期1389-1397,共9页
Two-dimensional transient laminar natural convection in a square cavity containing a porous medium and inclined at an angle of 30°is investigated numerically.The vertical walls are differentially heated,and the h... Two-dimensional transient laminar natural convection in a square cavity containing a porous medium and inclined at an angle of 30°is investigated numerically.The vertical walls are differentially heated,and the horizontal walls are adiabatic.The effect of Rayleigh number on heat transfer and on the road to chaos is analyzed.The natural heat transfer and the Darcy Brinkman equations are solved by using a finite volume method and a Tri Diagonal Matrix Algorithm(TDMA).The results are obtained for a porosity equal to 0.45,a Darcy number and a Prandtl respectively equal to 10^(-3)and 0.71;they are analyzed in terms of streamlines,isotherms,phase portrait,attractors,and spectra amplitude as a function of the Rayleigh number.It is found that,as Rayleigh number increases,the natural convection changes from a steady state to a time-periodic state and finally to a chaotic condition. 展开更多
关键词 Natural convection porous medium finite volumes CHAOS ATTRACTORS
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Is obesity related to the lung function of non-asthmatic children? 被引量:1
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作者 Andrew Fretzayas Maria Moustaki +1 位作者 Ioanna Loukou Konstantinos Douros 《World Journal of Clinical Pediatrics》 2018年第2期67-74,共8页
Overweight and obesity are highly prevalent in developed and developing countries among children and adolescents. During the last two decades, it became evident that excess weight is adversely related to respiratory h... Overweight and obesity are highly prevalent in developed and developing countries among children and adolescents. During the last two decades, it became evident that excess weight is adversely related to respiratory health in childhood and adolescence mainly in terms of asthma occurrence. Additionally, there is a mounting body of evidence that overweight/obesity may also affect lung function in non-asthmatic subjects. The aim of this review was to present and discuss the studies that investigated this issue in non-asthmatic children and adolescents. Only a few studies have evaluated the impact of excess weight on static volumes and their results point towards an inverse relationship between overweight/obesity and functional residual capacity. More studies have been conducted on the impact of excess weight on dynamic lung volumes with inconsistent, however, results. Nevertheless, a relatively consistent finding was that the ratio of forced expiratory volume in 1 s/forced vital capacity was significantly lower among overweight/obese children compared to their counterparts with normal weight. The underlying mechanisms of these observations have not been adequately elucidated but it is believed to result from complex interaction of mechanical, developmental, and metabolic causes. There is a need for more welldesigned studies in order to clarify the impact of excess weight on lung function in non-asthmatic subjects, as well as to explore the contribution of factors such as duration and degree of obesity, and fat distribution. Despite the absence of conclusive data, there are stillconvincing evidence to be communicated to the children and their families as part of the arguments to encourage them to adopt a healthier lifestyle. 展开更多
关键词 OBESITY LUNG FUNCTION SPIROMETRY LUNG volumes PLETHYSMOGRAPHY
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