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Numerical simulation on gradient cooling behavior of jumbo slab ingot

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China Foundry 2013年第2期10卷 87-91页

作者： Lü Nan Jin Yonglong li shengli Ai Xingang Yuan Xiaoguang School of Materials and Metallurgy University of Science and Technology Liaoning Tangshan Iron and Steel Group Corporation Shenyang University of Technology

Shrinkage porosity defect is often found in an air cooled jumbo steel ingot, which will influence the quality of the final rolled plates. In practical production, some rolled plates are frequently rejected due to the serious shrinkage porosity of the ingot. To improve the quality of the ingot, a new cooling method, gradient cooling process (in which the upper part of the ingot is air cooled and the lower part is spray cooled) was put forward in this study. The solidification behaviors for a 60 t jumbo slab ingot under gradient cooling condition were simulated using the ProCast software, and the results were compared with those of an ingot by air cooling condition. The solidifying tendency, temperature field and distribution of shrinkage porosities in the ingot under different cooling conditions were analyzed. Simulation results show that under gradient cooling condition the solidification of the slab ingot progresses in an upward manner along the vertical z axis and in a centripetal manner along the horizontal x and y axes. Gradient cooling can efficiently reduce shrinkage porosity of the jumbo slab ingot by optimizing the solidification sequence, and making the position of shrinkage porosity move from near the middle height of the ingot (under air cooling condition) towards the head of the ingot; and the secondary shrinkage is eliminated. In addition, the solidification time of the ingot under gradient cooling is 7.3 h in this simulation, which is 2.7 h faster than that under air cooling. A 60 t jumbo slab ingot was successfully produced under gradient cooling condition. The ingot was rolled to a plate with a thickness of 100 mm and length of 18,000 mm, and ultrasonic flaw detection was performed. Some porosity was found along the axis of the plate at 4,900 - 6,000 mm from the head of the plate, indicating that the position of the defect is moved towards the head of the ingot. This distribution trend of the defect is consistent with the simulated result.

关键词：空气冷却凝固行为数值模拟梯度扁锭巨型 PROCAST 缩孔缺陷

Supermicrosurgical lymphoevenous anastomosis for the treatment of peripheral lymphedema:A systematic review of the literature

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Chinese Journal Of Plastic and Reconstructive Surgery 2021年第3期3卷 155-160页

作者： Shoubao Wang Jingting Chen Zhaohua Jiang shengli li Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China

The effectiveness of supermicrosurgical lymphovenous anastomosis(LVA)for lymphedema treatment remains ***,no evidence has been *** study aimed to review the published literature on supermicrosurgical LVAs in the treatment of peripheral lymphedema and to analyze the surgical *** from databases(PubMed/MEDliNE,Cochrane Controlled Trial Data,and Embase)were collected to determine the effectiveness of supermicrosugrical LVAs for lymphedema.A systematic review was performed using individual patient *** studies,including 578 patients(482 female,72 male,and 24 unknown)with a mean age of 51 years,satisfied the needs of the study *** LVAs for peripheral lymphedema have demonstrated substantial improvements in both objective and subjective findings in many ***,in the long-term follow-up,the effectiveness of this treatment modality maintained a high efficacy of LVA in lymphedema ***,most studies provided low-quality evidence,and the conclusion is still not finalized.

关键词： Lymphedema Supermicrosurgery Lymphaticovenular anastomosis

Changes in feed intake, nutrient digestion, plasma metabolites, and oxidative stress parameters in dairy cows with subacute ruminal acidosis and its regulation with pelleted beet pulp

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Journal of Animal Science and Biotechnology 2014年第1期5卷 64-73页

作者： Yongqing Guo Xiaofeng Xu Yang Zou Zhanshan Yang shengli li Zhijun Cao State Key Laboratory of Animal Nutrition College of Animal Science &Technology China Agricultural University

The objectives of this study were to 1） determine the variation of nutrient digestion, plasma metabolites and oxidative stress parameters triggered by induced subacute ruminal acidosis （SARA）; and 2） evaluate the ability of pelleted beet pulp （BP） as a replacement for ground corn to alleviate SARA. Eight Holstein-Friesian cows were fed four diets during four successive17 day periods： 1） total mixed ration （TMR） containing 0% finely ground wheat （FGW）（WO）; 2） TMR containing 10% FGW （W10）; 3） TMR containing 20% FGW （W20）; and 4） TMR containing 10% BP as a replacement for 10% ground corn （BP10）. The SARA induction protocol reduced the mean ruminal pH from 6.37 to 5.94, and the minimum ruminal pH decreased from 5.99 to 5.41 from baseline to challenge period. Mean ruminal pH increased from 5.94 to 6.05, and minimum daily ruminal pH increased from 5.41 to 5.63, when BP was substituted for corn. The apparent digestibility of nutrients was not affected by the dietary treatments, except that the digestibility of neutral detergent fibre （NDF） and acid detergent fibre （ADF） was reduced in cows fed the W20 diet compared with cows fed the W0 and W10 diets, and cows fed the BP10 diet had higher NDF and ADF digestibility than the cows fed the W20 diet. Cows fed the W20 diet had a lower plasma concentration of 13-hydroxybutyrate （BHBA）, non-esterified fatty acids （NEFA）, cholesterol, triglyceride, and total antioxidative capacity （TAC）, and a higher plasma concentration of glucose, insulin, malonaldehyde （MDA）, super oxygen dehydrogenises （SOD）, and glutathione peroxidase （GSH-Px） than cows fed the W0 diet. Substitution of BP for corn increased concentrations of plasma BHBA and TAC, but decreased concentrations of plasma MDA. Our results indicate that reduction of fibre digestion; the concomitant increase of plasma glucose and insulin; the decrease of plasma BHBA, NEFA, cholesterol, and triglyceride; and changes of plasma oxidative stress parameters are highly related to SARA indu

关键词： Beet pulp Dairy cow Nutrient digestion Oxidative status Plasma metabolites Subacute ruminal acidosis

Patterns of gas hydrate accumulation in mass transport deposits related to canyon activity: Example from Shenhu drilling area in the South China Sea

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Acta Oceanologica Sinica 2019年第5期38卷 118-128页

作者： Chao Fu shengli li Xinghe Yu Jinqiang liang Zenggui Kuang Yulin He lina Jin School of Energy Resources China University of Geosciences Guangzhou Marine Geological Survey China Geological Survey

Since 2017, a plenty of gas hydrates have been drilled in a new area of Shenhu, and good heterogeneity has been found throughout the spatial distribution of the reservoir. After distinguishing different sedimentary sequence types and matching their formation with slope deposition settings, this study proposes three mass transport deposit(MTD) patterns related to canyon activity that occurred contemporaneously or epigenetically with it: well preserved MTDs, MTDs eroded by canyon migration, and MTDs dislocated by contemporaneous faults. Based on seismic reflection characteristics, this study proposed methods of quantitatively analyzing sedimentary factors,such as measuring the turbidities flow rate in the canyon, and results are interpreted with respect to canyon activity. Combining the above parameters and their relationship with gas hydrate accumulation, fine-grained seals overlapping coarse MTDs reservoirs are found to be indispensable to gas hydrate accumulation, as they prevent the release of free gas. Based on grain size data of hydrate samples from drilling wells, multi-layered gas hydrate reservoirs capped by fine-grained sediments and overlapping mud show favorable hydrate-bearing prospects. The release of gas hydrates, however, is mostly caused by the lack of mud sealing in relation to canyon activity, such as turbidities flow erosion and contemporaneous fault breaking. Canyon migration with respect to MTDs may be the actual cause of erosion of overlapping syn-sedimentary layers, and high bottom flows may contribute to an increase in the release of free gas. It is believed that contemporaneous faults caused by unstable canyon walls may break the muddy over layers and decrease the accumulation pressure of gas hydrate ***, according to the sedimentary characteristics of MTDs and the hydrate accumulation process, three responding accumulation or releasing patterns are proposed, which respond to the different types of MTDs distinguished above: a well-pr

关键词： South China Sea gas hydrate sedimentary characteristics MTDs hydrate responding pattern

Review： Utilization of yeast of Saccharomyces cerevisiae origin in artificially raised calves

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Journal of Animal Science and Biotechnology 2017年第3期8卷 549-560页

作者： Gibson M.Alugongo Jianxin Xiao Zhaohai Wu shengli li Yajing Wang Zhijun Cao State Key Laboratory of Animal Nutrition Department of Animal Nutrition and Feed Sciences China Agricultural University Beijing People's Republic of China

Yeast of Saccharomyces cerevisiae（SCY） origin has over long time been incorporated into domestic animal diets. In calves, several products have offered improved performance and health. Although several types of research have been completed, the mode of action of SCY is not clear in calves. Under this review, we have highlighted the works available in the literature on the use of SCY in calves performance, health, immunity, and the gut environment. Both active live yeast and yeast culture have positive effects on growth, rumen, small intestines, immunity and general health of the calf. Specifically, SCY can improve DMI, growth, feed efficiency and reduce diarrhea in calves. Furthermore, subtle improvements are seen in rumen fermentation（increased butyrate production） and rumen papillae growth. These positive results are, however, more pronounced in calves that are under stress or exposed to significant levels of disease-causing agents. There is a need for further research in areas such as gut morphology, gut microbiology and immunity using latest molecular methods to fully understand how SCY helps the growth and development of calves.

关键词： Active live yeast Calves Health Yeast culture

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产前超声诊断先天性心脏病胎儿的基因特征

中国医学影像技术 2024年第2期40卷 251-255页

作者：梁博诚罗丹丹罗彩群谭莹欧阳淑媛廖伊梅袁鹰文华轩李胜利南方医科大学第一临床医学院广东广州510515 深圳市妇幼保健院超声科广东深圳518028 深圳市妇幼保健院母胎医学中心广东深圳518028 深圳市妇幼保健院医学遗传中心广东深圳518028

目的观察产前超声诊断先天性心脏病(CHD)胎儿的基因特征。方法回顾性分析613胎经产前超声诊断CHD的单胎胎儿资料,并将其分为8类心脏结构异常;其中40胎因染色体核型分析和/或染色体微阵列分析(CMA)提示良性拷贝数变异(CNV)或临床意义... 详细信息

目的观察产前超声诊断先天性心脏病(CHD)胎儿的基因特征。方法回顾性分析613胎经产前超声诊断CHD的单胎胎儿资料,并将其分为8类心脏结构异常;其中40胎因染色体核型分析和/或染色体微阵列分析(CMA)提示良性拷贝数变异(CNV)或临床意义不明确的CNV(VUS)而接受全外显子测序(WES)。结果 613胎CHD中,479胎接受染色体核型分析及CMA,基因检测显示60胎(60/479,12.53%)存在异常;134胎仅接受CMA,基因检测显示4胎(4/134,2.99%)存在异常。568胎为孤立性、45胎为非孤立性CHD,分别有40胎(40/568,7.04%)及15胎(15/45,33.33%)染色体核型分析和/或CMA显示异常。复合型CHD(10/41,24.39%)染色体核型分析和/或CMA异常检出率高于非复合型(54/572,9.44%)。复合型CHD中,染色体核型分析和/或CMA异常检出率在圆锥动脉干畸形(CTD)合并静脉系统畸形胎儿中最高,达30.77%(4/13);非复合型CHD中,染色体核型分析和/或CMA异常检出率在内脏反位胎儿中最高,为25.00%(1/4)。染色体核型分析和/或CMA结果提示良性CNV或VUS的40胎中,WES提示3胎为致病性/可能致病性CNV(P/LP)、3胎为VUS、34胎为良性CNV。结论 CHD胎儿、尤其合并心外畸形者可能存在基因异常;CTD胎儿合并其他类型心脏结构异常时,基因异常可能性更大。相比单纯CMA,染色体核型分析联合CMA更有助于发现基因异常。

关键词：心脏缺损先天性胎儿基因检测超声检查

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继发性鼻缺损畸形的耳前皮瓣游离移植修复

中国眼耳鼻喉科杂志 2024年第3期24卷 170-172页

作者：李圣利曹卫刚蒋朝华戴婷婷盛玲玲崔春晓王守宝于子优上海交通大学医学院附属第九人民医院整复外科上海200011 上海交通大学医学院附属儿童医学中心烧伤整复外科上海200127

目的观察应用吻合血管的耳前皮瓣修复鼻部肿瘤治疗后的继发缺损畸形的效果。方法2007年2月—2019年10月收治的鼻部肿瘤治疗后部分鼻缺损病例6例,其中鼻翼和侧鼻部位缺损5例,鼻尖缺损1例。切取以颞浅血管远端为蒂的耳前皮瓣,应用显微外... 详细信息

目的观察应用吻合血管的耳前皮瓣修复鼻部肿瘤治疗后的继发缺损畸形的效果。方法2007年2月—2019年10月收治的鼻部肿瘤治疗后部分鼻缺损病例6例,其中鼻翼和侧鼻部位缺损5例,鼻尖缺损1例。切取以颞浅血管远端为蒂的耳前皮瓣,应用显微外科技术将颞浅动静脉远端与面动静脉吻合,游离移植修复。耳前皮瓣的大小为3.0 cm×2.5 cm~6.0 cm×2.5 cm。结果6例患者游离移植的耳前皮瓣全部成活,鼻部缺损得以良好修复。耳前供区直接缝合未见明显畸形。结论耳前皮瓣游离移植对鼻部肿瘤术后继发缺损畸形的修复有独到的价值。

关键词：肿瘤鼻缺损耳前皮瓣显微修复颞浅动脉

胎儿颅脑正中矢状位MRI脑桥生物学指标与孕周的相关性

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中国医学影像技术 2024年第1期40卷 88-92页

作者：侯伶秀刘炳光袁鹰廖伊梅朱巧珍郭洪波谭莹温慧莹严芳李胜利南方医科大学第一临床医学院广东广州510515 深圳妇幼保健院超声科广东深圳518028 桂林医学院附属医院超声医学科广西桂林541001 深圳妇幼保健院放射科广东深圳518028 河源市人民医院超声科广东河源517000 深圳妇幼保健院妇幼医学研究所广东深圳518028

目的观察胎儿颅脑正中矢状位MRI脑桥生物学指标与孕周的相关性。方法回顾性分析226胎孕23~38周中枢神经系统未见明显异常胎儿(正常组)及17胎异常胎儿(异常组)头部MRI,基于正中矢状位图像获得脑桥生物学指标,包括脑桥前后径(PAD)、脑桥... 详细信息

目的观察胎儿颅脑正中矢状位MRI脑桥生物学指标与孕周的相关性。方法回顾性分析226胎孕23~38周中枢神经系统未见明显异常胎儿(正常组)及17胎异常胎儿(异常组)头部MRI,基于正中矢状位图像获得脑桥生物学指标,包括脑桥前后径(PAD)、脑桥截面积(TPA)、脑桥基底部前后径(AP)、脑桥基底部上下径(CC)、脑桥基底部截面积(BPA)及中脑脑桥角(MAP)。根据孕周将正常组胎儿分为8个亚组,统计不同孕周胎儿脑桥生物学指标分布范围,分析正常组胎儿脑桥生物学指标与孕周的相关性,并据以判断异常组胎儿脑桥发育。结果正常组胎儿PAD、TPA、AP、CC及BPA均与孕周均呈线性正相关(r=0.887、0.914、0.787、0.866、0.865,P均0.05)。异常组17胎中,8胎PAD异常、8胎TPA异常、14胎AP异常、3胎CC异常、11胎BPA异常。结论胎儿颅脑正中矢状位MRI脑桥生物学指标(PAD、TPA、AP、CC、BPA)与孕周呈正相关,可用于评估胎儿脑桥发育。

关键词：胎儿脑桥磁共振成像

Effect of reduced energy density of close-up diets on dry matter intake,lactation performance and energy balance in multiparous Holstein cows

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Journal of Animal Science and Biotechnology 2015年第1期6卷 47-54页

作者： Wenming Huang Yujia Tian Yajing Wang Aminamu Simayi Amingguli Yasheng Zhaohai Wu shengli li Zhijun Cao State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural University

Energy intake prepartum is critically important to health, milk performance, and profitability of dairy cows. The objective of this study was to determine the effect of reduced energy density of dose-up diets on dry matter intake （DMI）, lactation performance and energy balance （EB） in multiparous Holstein cows which were housed in a free-stall barn and fed for ad libitum intake. Thirty-nine dry cows were blocked and assigned randomly to three groups fed a high energy density diet [HD, n = 13; 6.8 MJ of net energy for lactation （NEL）/kg; 14.0% crude protein （CP） ], or a middle energy density diet （MD, n = 13; 6.2 MJ NEh/kg; 14.0% CP）, or a low energy density diet （LD, n = 13; 5.4 MJ NEh/kg; 14.0% CP） from d 21 before expected day of calving. After parturition, all cows were fed the same lactation diet to d 70 in milk （DIM）. The DMI and NEE intake prepartum were decreased by the reduced energy density diets （P 〈 0.05）. The LD group consumed 1.3 last 24 h before calving. The milk yield and the postpartum kg/d （DM） more diet compared with HD group in the DMI were increased by the reduced energy density diet prepartum （P 〈 0.05）. The changes in BCS and BW prepartum and postpartum were not affected by prepartum diets HD group had higher milk fat content and lower lactose content compared with LD group during the first 3 wk of lactation （P 〈 0.05）. The energy consumption for HD, MD and LD groups were 149.8%, 126.2% and 101.1 % of their calculated energy requirements prepartum （P 〈 0.05）, and 72.7%, 73.1% and 7.5.2% during the first 4 wk postpartum, respectively. In conclusion, the low energy density prepartum diet was effective in controlling NF_L intake prepartum, and was beneficial in increasing DMI and milk yield, and alleviating negative EB postpartum.

关键词： Dietary energy density Dry matter intake Energy balance Lactation performance Transition cow