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Growth Efficiency of Local Chickens Using Sweet Potato Vine with Concentration Feed as a Basal Diet
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作者 Hieak Hun Suheang Sorn +4 位作者 Chan Bun Manay Ith Ty Chhay Kouch Theng Chetra Sar 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第3期108-113,共6页
The experiment was conducted at the animal experimental station of the Faculty of Animal Sciences,Royal University of Agriculture,commenced from 10 January to 14 March,2022.The CRD(Completely Randomized Design)was use... The experiment was conducted at the animal experimental station of the Faculty of Animal Sciences,Royal University of Agriculture,commenced from 10 January to 14 March,2022.The CRD(Completely Randomized Design)was used with 5 treatments and 4 replications.The 500 chicks at one-day-old,local bread,were purchased from farmers who run their small scale hatchery farm.The chicks were kept together till 21 days old,and then were allocated randomly into in five diets(treatments),25 chicks per replication.The feed formulas for this study were designed and calculated to maintain a protein content of approximately 17%,dividing into 5 feed formulas(Treatments),such as concentrated feed only(control treatment:T0),plus 10%of fresh sweet potato vine(T1),plus 20%of fresh sweet potato vine(T2),plus 30%of fresh sweet potato vine(T3)and plus 20%of sweet potato vine meal(T4).The results showed that the treatment T1,had a similar final weight with the treatment T4,but was slightly lower than the treatment T0 which used concentrated feed alone.Feed intake and FCR(Feed Conversion Ratio)were not significantly different among those treatments.In conclusion,the average daily weight gain of chickens seemed to decrease with increasing the level of fresh sweet potato vine.Thus,the optimum level of fresh sweet potato vine was 10%,which may have little effect on the growth performance of local chickens.In addition,it was not far different from the positive control treatment and the treatment using sweet potato vine meal.However,the producers can increase the amount of sweet potato vine in feed formula by processing it into meal and mixing with concentrated feed or using as feed ingredients. 展开更多
关键词 Local breed final weight feed intake FCR
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Intoxication Induced by Urea Containing Diets in Broiler Chickens: Effect on Weight Gain, Feed Conversion Ratio, Hematological and Biochemical Profiles
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作者 Mohammed Al-Zharani Mohammed Mubarak +2 位作者 Hassan Ahmed Rudayni Mahmoud M. Abdelwahab Mohammed Al-Eissa 《Advances in Bioscience and Biotechnology》 CAS 2023年第3期106-119,共14页
Urea as a source of cheap non-protein nitrogen is used to adulterate fish and meat meals which are basic components of broiler diets. The present study was carried out to elucidate the effects of urea on weight gain, ... Urea as a source of cheap non-protein nitrogen is used to adulterate fish and meat meals which are basic components of broiler diets. The present study was carried out to elucidate the effects of urea on weight gain, and hematological and biochemical profiles. A total of 48 broiler chicks were randomly allotted into 4 groups, designated Groups 1, 2, 3 and 4 of 12 birds each. Birds in Groups 2, 3 and 4 were fed on diets containing urea at the levels of 1%, 2.5% and 4%, respectively. Birds in Group 1 served as control and were not exposed to urea. Experimentation period was for 3 weeks and experiment was terminated when birds were 42 days of age. Body weight of all intoxicated birds at the various intervals was significantly decreased in comparison with that of the untreated control. Compared with control, all intoxicated broilers manifested significant (P ≤ 0.05) decrease in all hematological parameters involving erythrocytic and total leucocytic counts, Hemoglobin (Hb) and Packed Cell Volume (PCV) on a dose- and time-pattern. In comparison with the control levels, biochemical profile of the intoxicated birds disclosed significant decrease in blood glucose level and significant increase in serum uric acid, urea, Alkaline Phosphatase (ALP) and Lactate Dehydrogenase (LDH) levels. Based upon the present data, it was concluded that the addition of urea to broiler diets bears serious sequences concerning the general health condition, performance, weight gain, and hematological and biochemical profiles. 展开更多
关键词 UREA INtoXICATION Broiler Chickens weight Gain feed Conversion ratio
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Effects of Temperature and Catalyst to Oil Weight Ratio on the Catalytic Conversion of Heavy Oil to Propylene Using ZSM-5 and USY Catalysts 被引量:10
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作者 Xiaohong Li Chunyi Li Jianfang Zhang Chaohe Yang Honghong Shan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第1期92-99,共8页
It is useful for practical operation to study the rules of production of propylene by the catalytic conversion of heavy oil in FCC (fluid catalytic cracking). The effects of temperature and C/O ratio (catalyst to o... It is useful for practical operation to study the rules of production of propylene by the catalytic conversion of heavy oil in FCC (fluid catalytic cracking). The effects of temperature and C/O ratio (catalyst to oil weight ratio) on the distribution of the product and the yield of propylene were investigated on a micro reactor unit with two model catalysts, namely ZSM-5/Al2O3 and USY/Al2O3, and Fushun vacuum gas oil (VGO) was used as the feedstock. The conversion of heavy oil over ZSM-5 catalyst can be comparable to that of USY catalyst at high temperature and high C/O ratio. The rate of conversion of heavy oil using the ZSM-5 equilibrium catalyst is lower compared with the USY equilibrium catalyst under the general FCC conditions and this can be attributed to the poor steam ability of the ZSM-5 equilibrium catalyst. The difference in pore topologies of USY and ZSM-5 is the reason why the principal products for the above two catalysts is different, namely gasoline and liquid petroleum gas (LPG), repspectively. So the LPG selectivity, especially the propylene selectivity, may decline if USY is added into the FCC catalyst for maximizing the production of propylene. Increasing the C/O ratio is the most economical method for the increase of LPG yield than the increase of the temperature of the two model catalysts, because the loss of light oil is less in the former case. There is an inverse correlation between HTC (hydrogen transfer coefficient) and the yield of propylene, and restricting the hydrogen transfer reaction is the more important measure in increasing the yield of propylene of the ZSM-5 catalyst. The ethylene yield of ZSM-5/A1203 is higher, but the gaseous side products with low value are not enhanced when ZSM-5 catalyst is used. Moreover, for LPG and the end products, dry gas and coke, their ranges of reaction conditions to which their yields are dependent are different, and that of end products is more severe than that of LPG. So it is clear that maximizing LPG and propylene and restricting dry gas and coke can be both achieved via increasing the severity of reaction conditions among the range of reaction conditions which LPG yield is sensitive to. 展开更多
关键词 fluid catalytic cracking heavy oil PROPYLENE temperature catalyst to oil weight ratio ZSM-5 USY
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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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Therapeutic effect of nerve growth factor on cerebral infarction in dogs using the hemisphere anomalous volume ratio of diffusion-weighted magnetic resonance imaging 被引量:9
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作者 Yong Wang Hui Zhang +5 位作者 Zhe Wang Zuojun Geng Huaijun Liu Haiqing Yang Peng Song Qing Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1873-1880,共8页
A model of focal cerebral ischemic infarction was established in dogs through middle cerebral artery occlusion of the right side.Thirty minutes after occlusion,models were injected with nerve growth factor adjacent to... A model of focal cerebral ischemic infarction was established in dogs through middle cerebral artery occlusion of the right side.Thirty minutes after occlusion,models were injected with nerve growth factor adjacent to the infarct locus.The therapeutic effect of nerve growth factor against cerebral infarction was assessed using the hemisphere anomalous volume ratio,a quantitative index of diffusion-weighted MRI.At 6 hours,24 hours,7 days and 3 months after modeling,the hemisphere anomalous volume ratio was significantly reduced after treatment with nerve growth factor. Hematoxylin-eosin staining,immunohistochemistry,electron microscopy and neurological function scores showed that infarct defects were slightly reduced and neurological function significantly improved after nerve growth factor treatment.This result was consistent with diffusion-weighted MRI measurements.Experimental findings indicate that nerve growth factor can protect against cerebral infarction,and that the hemisphere anomalous volume ratio of diffusion-weighted MRI can be used to evaluate the therapeutic effect. 展开更多
关键词 diffusion-weighted MRI nerve growth factor hemisphere anomalous volume ratio cerebral infarction treatment NEUROPROTECTION brain regeneration neural regeneration
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Feasibility study on buoyancy-weight ratios of a submerged floating tunnel prototype subjected to hydrodynamic loads 被引量:7
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作者 Xu Long Fei Ge Youshi Hong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第5期750-761,共12页
The research progress of a novel traffic solution,a submerged floating tunnel(SFT),is reviewed in terms of a study approach and loading scenario.Among existing publications,the buoyancy-weight ratio(BWR) is usuall... The research progress of a novel traffic solution,a submerged floating tunnel(SFT),is reviewed in terms of a study approach and loading scenario.Among existing publications,the buoyancy-weight ratio(BWR) is usually predefined.However,BWR is a critical structural parameter that tremendously affects the dynamic behaviour of not only the tunnel tube itself but also the cable system.In the context of a SFT prototype(SFTP) project in Qiandao Lake(Zhejiang Province,China),the importance of BWR is illustrated by finite element analysis and subsequently,an optimized BWR is proposed within a reasonable range in the present study.In the numerical model,structural damping is identified to be of importance.Rayleigh damping and the corresponding Rayleigh coefficients are attained through a sensitivity study,which shows that the adopted damping ratios are fairly suitable for SFTP.Lastly,the human sense of security is considered by quantifying the comfort index,which helps further optimize BWR in the SFTP structural parameter design. 展开更多
关键词 Submerged floating tunnel Buoyancy-weight ratio Water wave and current loads Dynamic response Human security sense Comfort index
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Molecular Weight Distribution of Polystyrene Produced in a Starved Feed Reactor
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作者 曹贵平 朱中南 +1 位作者 乐慧慧 张明华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1999年第3期205-213,共9页
A starved feed reactor (SFR) is a semi-batch polymerization reactor where initiator and monomer are fed slowly into a fixed amount of solvent. The polymerization is carried out isothermally at elevated temperatures. T... A starved feed reactor (SFR) is a semi-batch polymerization reactor where initiator and monomer are fed slowly into a fixed amount of solvent. The polymerization is carried out isothermally at elevated temperatures. The added initiator decomposes instantaneously and the added monomer polymerizes immediately. The molecular weight (MW) and molecular weight distribution (MWD) of the product polymer can be effectively controlled by the feed ratio of monomer to initiator. This paper presents a study on the MWD of styrene polymerization in a SFR. The MWD model parameters are regressed with experimental data. Although the solids fraction in the SFR is high (higher than 50%), viscosity is not too high and the 'gel effect' is weak due to the low molecular weight of the products. It is found that the termination rate constant is a power function of molecular weight, radicals terminate via 100% combination, the thermal initiation can be neglected even at high reaction temperature studied. And calculated results indicate that in the SFR, the validity of the long chain assumption becomes doubted. It appears that other alterative assumption should be found for an improved model. 展开更多
关键词 starved feed reactor molecular weight distribution STYRENE radical polymerization
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Successful living donor liver transplantation with a graft-to-recipient weight ratio of 0.41 without portal flow modulation:A case report
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作者 Seong Hoon Kim 《World Journal of Clinical Cases》 SCIE 2022年第16期5414-5419,共6页
BACKGROUND There have been numerous efforts to lower the limit of minimum graft size to meet the metabolic demand of recipients in adult-to-adult living donor liver transplantation(LDLT).We experienced a successful ca... BACKGROUND There have been numerous efforts to lower the limit of minimum graft size to meet the metabolic demand of recipients in adult-to-adult living donor liver transplantation(LDLT).We experienced a successful case of LDLT using a verysmall-for-size graft without portal flow modulation such as splenectomy or portocaval shunt.CASE SUMMARY A 49-year-old man(weighing 91 kg)suffering hepatocellular carcinoma accompanied with hepatitis B virus related cirrhosis underwent LDLT.The one and only voluntary donor was his 17-year-old daughter whose body weight was 50 kg with a body mass index(BMI)of 18.3.The procured right liver graft was 411 g with a real graft-to-recipient weight ratio(GRWR)of 0.41%,the smallest to be reported in the literature.Both the recipient and donor had an uneventful recovery and were discharged on days 15 and 8,respectively,with normal liver function.The father and daughter have had no complication so far and are still in good health with normal liver function 81 mo after LDLT.CONCLUSION Satisfactory outcomes can be achieved in LDLT with a GRWR as low as 0.41%even without using portal flow modulation in highly selected patients. 展开更多
关键词 Small-for-size graft Living donor liver transplantation Graft-to-recipient weight ratio Case report
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Effects of Fiber Weight Ratio, Structure and Fiber Modification onto Flexural Properties of Luffa-Polyester Composites
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作者 Lassaad Ghali Slah Msahli +1 位作者 Mondher Zidi Faouzi Sakli 《Advances in Materials Physics and Chemistry》 2011年第3期78-85,共8页
The effect of chemical modification, reinforcement structure and fiber weight ratio on the flexural proprieties of Luffa-polyester composites was studied. A unsaturated polyester matrix reinforced with a mat of Luffa ... The effect of chemical modification, reinforcement structure and fiber weight ratio on the flexural proprieties of Luffa-polyester composites was studied. A unsaturated polyester matrix reinforced with a mat of Luffa external wall fibers (ComLEMat), a short Luffa external wall fibers(ComLEBC) and a short Luffa core fi-bers (ComLCBC) was fabricated under various conditions of fibers treatments (combined process, acetylat-ing and cyanoethylating) and fiber weight ratio. It resorts that acetylating and cyanoethylating enhance the flexural strength and the flexural modulus. The fiber weight ratio influenced the flexural properties of com-posites. Indeed, a maximum value of strength and strain is observed over a 10% fiber weight ratio. The uses of various reinforcement structures were investigated. The enhancement of elongation at break and the strain values of the composite reinforced by natural mat was proved. 展开更多
关键词 LUFFA Fibers COMPOSITE FLEXURAL Properties FIBER weight ratio
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The spike weight contribution of the photosynthetic area above the upper internode in a winter wheat under different nitrogen and mulching regimes 被引量:5
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作者 Wei Chen Jingjuan Zhang Xiping Deng 《The Crop Journal》 SCIE CAS CSCD 2019年第1期89-100,共12页
Besides leaves, non-foliar green organs such as stem and spike are also considered photosynthetic organs. To assess the photosynthetic contributions of these organs, the correlations between these photosynthetic areas... Besides leaves, non-foliar green organs such as stem and spike are also considered photosynthetic organs. To assess the photosynthetic contributions of these organs, the correlations between these photosynthetic areas and single-spike weight were investigated in a winter wheat(Triticum aestivum L.) under four nitrogen and mulching treatments: N120,N150, N195, and N195 + M. Two-year repeated field experiments were conducted on the Loess Plateau of China. Non-foliar photosynthetic area, grain-filling ratio and duration,grain yield, and in particular, single-spike weight, were measured, recorded and analyzed.Under the N195 + M treatment, plants showed the largest area of photosynthetic organs(flag leaf and non-foliar organs) and the highest grain yield and single spike weight. Singlespike weight was positively correlated with the areas of all examined non-foliar photosynthetic organs, in particular with the area above the flag leaf node(R^2= 0.761*)and the area above the exposed part of the peduncle(EXP)(R^2= 0.800**). In addition, singlespike weight was highly correlated with average grain-filling ratio(R^2= 0.993**), whereas it was less highly correlated with grain-filling duration(R^2= 0.533). The morphological traits of non-foliar photosynthetic organs were also more highly correlated with average grainfilling ratio than with average grain-filling duration. The significant correlation between each of the morphological traits(area, length and width) of EXP and single-spike weight indicates that morphological traits of EXP are important in determining spike weight in the Loess Plateau environment. 展开更多
关键词 GRAIN-FILLING ratio GRAIN-FILLING duration LOESS Plateau PHOtoSYNTHETIC organs Single SPIKE weight Winter wheat
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Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions 被引量:8
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作者 Seung Duk Lee Seong Hoon Kim +2 位作者 Young-Kyu Kim Soon-Ae Lee Sang-Jae Park 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第1期18-24,共7页
BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate wh... BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. METHODS: From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7%(group A), 27 had a GRWR of ≥0.7%, 【0.8%(group B), and 267 had a GRWR of more than and equal to 0.8%(group C). Medical records, including recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. RESULTS: The baseline demographics showed low model for end-stage liver disease score(mean 16.3±8.9) and high percentage of hepatocellular carcinoma(231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For smallforsize syndrome, there were 3(13.0%) in group A, 1(3.7%) in group B, and 2 patients(0.7%) in group C(P【0.001). Hepatic artery thrombosis was more frequently observed in group A than in groups B and C(8.7% vs 3.7% vs 1.9%, P=0.047). However, among the three groups, graft survival rates at 1 year(100% vs 96.3% vs 93.6%) and 3 years(91.7% vs 73.2% vs 88.1%) were not different(P=0.539). In laboratory measurements,there was no group difference in total bilirubin and albumin. However, prothrombin time was longer in group A within postoperative 1 week and platelet count was lower in groups A and B within postoperative 1 month. CONCLUSION: A GRWR lower to 0.7% is safe and does not need to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score. 展开更多
关键词 graft-to-recipient weight ratio living donor liver transplantation small-for-size graft small-for-size syndrome
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Postoperative complications and weight loss following jejunostomy tube feeding after total gastrectomy for advanced adenocarcinomas 被引量:3
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作者 Hylke J.F. Brenkman Stephanie V.S. Roelen +2 位作者 Elles Steenhagen Jelle P. Ruurda Richard van Hillegersberg 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第4期333-340,共8页
Objective: Patients undergoing total gastrectomy for cancer are at risk of malnourishment. The aim of this self- controlled study was to examine the effect of jejunostomy tube feeding (JTF) and other factors on pos... Objective: Patients undergoing total gastrectomy for cancer are at risk of malnourishment. The aim of this self- controlled study was to examine the effect of jejunostomy tube feeding (JTF) and other factors on postoperative weight and the incidence of jejunostomy-related complications in patients undergoing total gastrectomy for cancer. Methods: All consecutive patients who underwent total gastrectomy for gastric cancer with jejunostomy plaeement were included from a prospective single-center database (2003-2014). Jejunostomy-related complications and postoperative weight changes were evaluated up to 12 months after surgery. Multivariable linear regression analysis was performed to identify factors associated with weight loss 12 months after gastreetomy. Results: Of 113 patients operated in the study period, 65 received JTF after total gastrectomy for a median duration of 18 d [interquartile range (IQR), 10-55 d]. Jejunostomy-related complieations occurred in 11 (17%) patients, including skin leakage (n=3) and peritoneal leakage (n=2), luxation (n=3), occlusion (n=2), infection (n=l) and torsion (n=l). In 2 (3%) patients, a reoperation was needed due to jejtmostomy-related complications. The mean preoperative weight of patients was 71.8 kg (100%), and remained stable during JTF (73.9 kg, 103%, P=0.331). After JTF was stopped, the mean weight of patients decreased to 64.9 kg (90%) at 12 months after surgery (P〈0.001). A high preoperative body mass index (BMI) (〉_25 kg/m2) was associated with high postoperative weight loss compared to patients with a low BMI (〈25 kg/m2) (16.3% vs. 8.6%, P=0.016). Conclusions: JTF can prevent weight loss in the early postoperative phase. However, this is at the prize of possible complications. As weight loss in the long term is not prevented, routine JTF should be re-evaluated and balanced against the selected use in preoperatively malnourished patients. Special attention should be paid to patients with a high preoperative BMI, who are at risk of more postoperative weight loss. 展开更多
关键词 Gastric cancer total gastrectomy jejunostomy tube feeding weight
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Experimental Investigation of Multi-Mode Vortex-Induced Vibration of Flexible Risers with Different Mass Ratios
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作者 WANG Yu LOU Min +3 位作者 REN Xiao-hui LIANG Wei-xing LI Xiang DANG Peng-bo 《China Ocean Engineering》 SCIE EI CSCD 2023年第1期1-15,共15页
Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 16... Experiments were conducted on risers with different mass ratios to study the effect of mode conversion and spanwise correlation. The slenderness ratio of the riser model was set as 169, and the Reynolds numbers are 1600-14400. The dynamic responses of riser models versus reduced velocity were analyzed, and the spanwise displacement, frequency,and trajectory of the mode conversion from the lower to the higher mode were explored. The results revealed that the riser model with a higher mass ratio excites a higher number of modes. The conversion region of multi-mode competition exists and narrows with the increasing mass ratio. Mode conversion is continuous and manifests as the transmission of peaks and troughs in mode shape: the peaks and troughs of mode shape move up in the mode stable development region and move down in the mode conversion region. The single-mode dominating vibration exhibits a standing wave feature, and the traveling wave feature is significant in the mode conversion region. Furthermore, the frequency jump is always transmitted from the trough to the peak of the mode shape, and finally, all the axial positions vibrate at the same frequency. The trajectory in the mode conversion region deviates from the 8-shape and recovers the standard8-shape at the middle and late stages of the mode stable development region. 展开更多
关键词 vortex-induced vibration dynamic response mode conversion mass ratio mode weight
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A Modified Bi-Directional Evolutionary Structural Optimization Procedure with Variable Evolutionary Volume Ratio Applied to Multi-Objective Topology Optimization Problem
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作者 Xudong Jiang Jiaqi Ma Xiaoyan Teng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期511-526,共16页
Natural frequency and dynamic stiffness under transient loading are two key performances for structural design related to automotive,aviation and construction industries.This article aims to tackle the multi-objective... Natural frequency and dynamic stiffness under transient loading are two key performances for structural design related to automotive,aviation and construction industries.This article aims to tackle the multi-objective topological optimization problem considering dynamic stiffness and natural frequency using modified version of bi-directional evolutionary structural optimization(BESO).The conventional BESO is provided with constant evolutionary volume ratio(EVR),whereas low EVR greatly retards the optimization process and high EVR improperly removes the efficient elements.To address the issue,the modified BESO with variable EVR is introduced.To compromise the natural frequency and the dynamic stiffness,a weighting scheme of sensitivity numbers is employed to form the Pareto solution space.Several numerical examples demonstrate that the optimal solutions obtained from the modified BESO method have good agreement with those from the classic BESO method.Most importantly,the dynamic removal strategy with the variable EVR sharply springs up the optimization process.Therefore,it is concluded that the modified BESO method with variable EVR can solve structural design problems using multi-objective optimization. 展开更多
关键词 Bi-directional evolutionary structural optimization variable evolutionary volume ratio multi-objective optimization weighted sum topology optimization
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Effects of Diets with Different Corn-to-Soybean Ratios on Performance of Lactational Rex Rabbits 被引量:1
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作者 SUN Li-na GU Zi-lin LIU Ya-juan LI Su-min 《Animal Husbandry and Feed Science》 CAS 2010年第1期24-26,31,共4页
[ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rab... [ Objective] To study the effects of diets with different com-to-soybean ratios on production performance of lactational Rex rabbits and select the best feed formula. [Method] A total of 80 lactational healthy Rex rabbits (similar age, body weight and delivery time) were randomly divided into five groups, 16 in each group. The Rex rabbits in group I were fed with corn-based meal diet, group II with soybean-based meal diet, group III with the developed corn-soybean meal diet, group IV with corn-soybean meal free diet, and group CK with conventional corn-soybean meal diet. During the lactation period, the changes in the lactation performance, growth rate of baby rabbits, weight and feed costs were observed. [ Result] The lactation performance of mother rabbits and the growth rate of baby rabbits in the experimental groups were similar to that in the control group. The weaning survival rate of the group III was the highest, but it was not significantly higher than that of the control group. The weaning survival rate of the other three groups was lower than that of the control group (P〈0.05). The weight loss of mother rabbits in the group I, II and III was not significantly different from that of the control group, but the weight loss of the group IV was higher than that of the control group ( P 〈 0.01 ). [ Conclusion] Diets with appropriate corn-to-soybean ratios not only reduce feed costs but also give the best feeding effects. 展开更多
关键词 Lactational Rex rabbits Lactation performance Growth rate weight feed costs
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Critical weight on bit of double-driven bottomhole assembly during vertical and fast drilling 被引量:1
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作者 祝效华 贾彦杰 童华 《Journal of Central South University》 SCIE EI CAS 2012年第2期572-577,共6页
It is difficult to determine the optimal weight on bit (WOB) of the double-driven bottomhole assembly (DD-BHA, with double stabilizers and a bent housing positive displacement motor (PDM)) which is employed during ver... It is difficult to determine the optimal weight on bit (WOB) of the double-driven bottomhole assembly (DD-BHA, with double stabilizers and a bent housing positive displacement motor (PDM)) which is employed during vertical and fast drilling. High WOB leads to well deviation out of control, and low WOB leads to low rate of penetration (ROP). So considering the rock physical properties, the anisotropy index function of polycrystalline diamond compact (PDC) bit was derived with the structure and cutting performance parameters of the bit, and the effect of natural hole deviation tendencies on the performance of DD-BHA resisting deviation was represented. The concept of elliptic deformation ratio was used to characterize the performance of DD-BHA resisting deviation. Eventually, a model calculating the critical WOB was established. By comparing the model predictions with the measured hole angle changes in the field, the results show that the model predictions are accurate with error less than 5.8%, which can meet the operational requirements in the projects. Furthermore, the model was adopted to justify and guide the operating conditions and parameters during drilling, which shows that the optimum WOB predicted by the model can not only control deviation but also improve ROP effectively. The model is independent on the formation characteristics of blocks, so it can be expanded widely to other oilfields. 展开更多
关键词 double-driven bottomhole assembly vertical and fast drilling critical weight of bit elliptic deformation ratio bit anisotropy
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Effects of Feeding Time on the Growth Performance and Variation of RNA/DNA Ratio of the Chinese Soft-shelled Turtle, Pelodiscus sinensis
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作者 Yingguang jI Haiyan LIU +1 位作者 Zhe SONG Zhencai YANG 《Asian Herpetological Research》 SCIE CSCD 2016年第4期271-277,共7页
The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00... The present study was to investigate the effects of feeding time on growth of the Chinese soft-shelled turtle. The experiment was carried out with a photoperiod of 12L (light): 12D (dark) with lights on at 06:00 and off at 18:00. Turtles were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the length of the experiment. The turtles in group 1 to group 6 were fed respectively at 00:00, 04:00, 08:00, 12:00, 16:00 and 20:00 with 60 turtles each (Initial body weight 88.27 - 0.09 g). Acrophases of postprandial RNA/DNA ratio in liver in each group was shown between 5h and 7h after feeding. A positive linear correlation could be seen between specific growth rate (SGR) and RNA/ DNA:SGR=t.1586RNA/DNA-0.7097 (r = 0.9328, P = 0.0066). The results indicated that the values at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shelled turtle. The turtles in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew slower than group 2, whose feed conversion rate was also higher. Meanwhile, the SGR and feeding rate of turtles fed at 12:00 were the lowest from the six groups (P 〈 0.05). Turtles fed in group 1, group 2 and group 6 developed more heavy final body weight (FBW), higher feeding rate and SGR than the other three groups. This probably suggested that turtles fed in scotophase grew better than that fed at photophase in total. 展开更多
关键词 feeding time Growth performance Pelodiscus sinensis RNA/DNA ratio
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基于熵权TOPSIS法与秩和比法的高校附属医院科技成果转化评价研究
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作者 赵佳洁 郝三元 +2 位作者 许紫文 许栋 陈任 《中国医院管理》 北大核心 2024年第11期18-24,共7页
目的评价安徽省某医科大学12家附属医院科技成果转化工作,为进一步优化高校附属医院科技成果转化提供建议。方法根据所收集的数据使用熵权法为评价指标体系赋权,采用TOPSIS法与秩和比法模糊联合进行综合评价。结果评价指标中权重排名前... 目的评价安徽省某医科大学12家附属医院科技成果转化工作,为进一步优化高校附属医院科技成果转化提供建议。方法根据所收集的数据使用熵权法为评价指标体系赋权,采用TOPSIS法与秩和比法模糊联合进行综合评价。结果评价指标中权重排名前3位的是以自行实施方式转化的到账总金额(4.801%),以与他人合作实施方式转化获得收益的到账总金额(4.801%),与所属高校共建研发机构、转移机构、转化服务平台数量(4.779%)。模糊联合结果中前3名医院分别为A、C、G,后3名分别为K、H、E。医院之间差异明显,直属附属医院与非直属附属医院存在差异。结论高校附属医院应探索一条具有自身特色的科技成果转化的发展道路,从实际出发作转化;将成果转化融入学科建设,深化拓展科研优势;构建转化意识提升体系,以意识提升带动行动;高校牵头医工融合,搭建医产学研新生态。 展开更多
关键词 科技成果转化 高校附属医院 熵权toPSIS法 秩和比法
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Carbon isotopic fractionation during vaporization of low molecular weight hydrocarbons(C6–C12)
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作者 Qian-Yong Liang Yong-Qiang Xiong +2 位作者 Jing Zhao Chen-Chen Fang Yun Li 《Petroleum Science》 SCIE CAS CSCD 2017年第2期302-314,共13页
Three series of laboratory vaporization experiments were conducted to investigate the carbon isotope fractionation of low molecular weight hydrocarbons(LMWHs)during their progressive vaporization.In addition to the ... Three series of laboratory vaporization experiments were conducted to investigate the carbon isotope fractionation of low molecular weight hydrocarbons(LMWHs)during their progressive vaporization.In addition to the analysis of a synthetic oil mixture,individual compounds were also studied either as pure single phases or mixed with soil.This allowed influences of mixing effects and diffusion though soil on the fractionation to be elucidated.The LMWHs volatilized in two broad behavior patterns that depended on their molecular weight and boiling point.Vaporization significantly enriched the ^13C present in the remaining components of the C6–C9 fraction,indicating that the vaporization is mainly kinetically controlled;the observed variations could be described with a Rayleigh fractionation model.In contrast,the heavier compounds(n-C10–n-C12)showed less mass loss and almost no significant isotopic fractionation during vaporization,indicating that the isotope characteristics remained sufficiently constant for these hydrocarbons to be used to identify the source of an oil sample,e.g.,the specific oil field or the origin of a spill.Furthermore,comparative studies suggested that matrix effects should be considered when the carbon isotope ratios of hydrocarbons are applied in the field. 展开更多
关键词 Low molecular weight hydrocarbons Gas chromatography-isotope ratio mass spectrometry Isotope fractionation VAPORIZATION
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Effect of Feed Restriction on Broiler Chicks Prior to Slaughter
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作者 Nadir Abdelraheem Magdi Mohammed Mohammed Ahmed Fujiang Hou 《Open Journal of Animal Sciences》 2019年第1期12-22,共11页
The present study was conducted to study the effect of feed restriction prior to slaughter on carcass weight of male broiler chicks from 32 to 40 days of age. A total number of 180 (Pure line) male broiler chicks were... The present study was conducted to study the effect of feed restriction prior to slaughter on carcass weight of male broiler chicks from 32 to 40 days of age. A total number of 180 (Pure line) male broiler chicks were taken randomly, labeled and divided into six groups. At 32 days of age, the experimental groups were put under the experimental feeding program. Group A fed ad libitum (control) while group B and C fed 120, 60 gm/bird/day for eight days, respectively. Group D and E fed 120, 60 gm/bird/day for four days respectively, followed by zero feeding for an extra 4 days. Group F deprived of food during the whole experimental period (8 days). The experimental diet was formulated to be approximately iso caloric-iso nitrogenous containing sorghum, groundnut cake, broiler concentrate, calcium, salt, lysine, methionine, and premix. The parameters taken were live body weight, feed intake, mortality, carcass, and non-carcass values. The effect of feed restriction program on male broiler chicks was not significant during the period from 32 to 34 days of age for parameters final live body weight, carcass weight, and dressing percentage, but net weight (gain or loss) was affected by feed restriction program and showed a significant difference (P < 0.01) between experimental groups. From 32 to 36 days of age male broilers subjected to feed restriction regimes showed the lowest reading for final live body weight, net weight (gain or loss) and carcass weight and the difference were significant (P 0.05) between experimental groups for dressing percentage during period from32 to 36 days of age. At the period from 32 to 38 days and the period from 32 to 40 days of age, all parameters were significantly affected by feed restriction program. It was concluded that carcass weight of broiler chickens can be controlled using different options of feed restriction programs according to the need of the market and the producer situation with special consideration to the economic return. 展开更多
关键词 feed RESTRICTION Prior to SLAUGHTER BROILER CARCASS weight
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