预处理对SFE提取月见草种子、被孢霉菌丝体油脂的影响

以月见草种子、被孢霉菌丝体为超临界流体萃取(SFE)的试验材料,研究了不同预处理条件(水分、粉碎度、粉碎方式)在不同萃取压力下对超临界流体萃取油脂得率的影响;确定粉碎度、粉碎方式、水分与油脂萃取之间的关系。     

大型矩形水工渡槽动力分析

针对大型矩形渡槽的动力特性和动力响应问题,建立了流固耦合(FSI)系统的位移-压力(ui,p)有限元格式,给出流固耦合系统的动力特性方程;基于FSI系统的(ui,p)格式建立槽体-水体-槽墩-基础-地基系统的力学模型,采用非对称模态提取法求解了4种水深下渡槽的动力特性,并用隐式-显式积分算法计算了4种水深、2种强震作用下大型渡槽的动力响应。计算结果表明,基于FSI的(ui,p)格式,考虑到槽体与水体的相互作用,简化了计算模型,提高了计算精度,同时也得出不同水深、不同激励下渡槽结构动力特性和动力响应的变化规律等结论,可为大型渡槽及同类工程动力设计提供参考。     

Supercritical fluid extraction of sapogenins from tubers of Smilax china

Supercritical CO(2) fluid extraction (SFE-CO(2)) was used to extract the sapogenins after acid hydrolysis from Smilax china tubers. The influence of extraction variables, such as modifier, pressure, temperature and extraction time, were studied. SFE-CO(2) was found to produce higher yield than conventional solvent extraction. The highest yield (0.454%) of sapogenins, mostly containing diosgenin, was obtained using 35 MPa pressure, 65 degrees C and 95% EtOH as a modifier for 180 min, higher than that obtained with conventional extraction methods (0.385%).     

天然动植物色素的特性及其提取技术概况

综述了天然生物色素在动植物体中的分布和特定生理功能。概括了动植物色素的主要提取方法及其发展状况：直接破碎原料、溶剂浸提、物理技术辅助浸提和现代仪器提取分离等;指出超临界流体萃取(SFE)是较具发展潜力的高效萃取方法,有利于提高色素产品质量。     

Influence of Disease Process and Duration on Acute Phase Proteins in Serum and Peritoneal Fluid of Horses with Colic

Background

The acute phase proteins (APP) serum amyloid A (SAA), haptoglobin, and fibrinogen are valuable blood biomarkers in equine inflammatory diseases, but knowledge of factors influencing their concentrations in blood and peritoneal fluid (PF) of horses with colic is needed.

Objectives

The objective of this study was to investigate the influence of demographics (age, sex, breed), disease process (simple obstruction, strangulating obstruction, inflammatory), disease location, disease duration, hypovolemia, and admission hospital on concentrations of APP, lactate and white blood cell counts (WBC) in horses with colic admitted to 2 referral hospitals.

Animals

The study included 367 horses with colic admitted at 2 referral hospitals.

Methods

Prospective multicenter observational study of clinical data, as well as blood and PF biomarkers. Associations between biomarker concentrations and clinical variables were analyzed using multivariate linear regression analysis.

Results

Increasing pre‐admission duration of colic was associated with increased concentrations of APP in blood and PF. Blood concentrations of SAA and fibrinogen were associated with disease process (inflammatory, strangulations, simple obstructions) in more colic duration groups (5–12 and >24 hours) than any of the other biomarkers. No relevant associations between demographic factors, hospital, or hydration status and the measured biomarkers were found.

Conclusions and Clinical Importance

In horses with colic, concentrations of APP are associated mainly with disease process and duration of colic and may thus be used for assessment of disease independently of demographic or geographic factors. Serum amyloid A may be a diagnostic marker for use in colic differential diagnosis, but further evaluation is needed.     

Synovial fluid total protein concentration as a possible marker for canine idiopathic polyarthritis

Idiopathic polyarthritis (IPA) is a very common inflammatory arthropathy in the dog. Canine IPA is diagnosed mainly by detecting increased number of leukocytes in the synovial fluid (SF), which is easily influenced by glucocorticoid therapy. We obtained 31 SF samples from 24 IPA dogs prior to (n=19) and/or after (n=12) 1 to 10 weeks of glucocorticoid therapy. The SF total protein concentrations of IPA dogs were significantly higher than those of dogs with non-arthritis diseases (n=34) and healthy controls (n=10). Our data revealed that the SF total protein concentrations are not influenced by several weeks of glucocorticoid therapy. Hence, the SF total protein concentration is applicable as a diagnostic marker of canine IPA even when the patients are receiving glucocorticoid therapy.     

Changes in the predicted function of the rumen bacterial community of Japanese Black beef cattle during the fattening stages according to Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses

We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet.     

长航时轻型固定翼农用遥感无人机设计与仿真

针对电动无人机应用于农业遥感监测时受其续航时间限制的问题,从实际应用角度出发,设计了一种续航时间长、适用于农业遥感监测的翼身融合布局的轻型电动固定翼无人机。提出了翼身融合布局轻型固定翼无人机的总体设计方法,确定了轻型固定翼无人机的结构参数,建立了物理模型并对其参数进行了优化分析。通过计算流体力学(Computational fluid dynamics,CFD)分析计算了翼身融合布局轻型固定翼无人机的气动性能,基于流固耦合模型动态分析了其飞行状态下的受力分布。结果表明,优化模型较初始设计模型的升阻比提高了2.6%,在迎角为6°、巡航速度为15.5 m/s时,所设计的翼身融合布局轻型固定翼无人机机身压力分布合理,且拥有良好的气动特性。起飞质量为1.5 kg时,无人机下表面压力最大,为143 Pa,升力主要集中在机翼前缘部分,计算所得理论续航时间为65 min,在巡航阶段最大变形量0.288 38 mm,符合飞行器工作条件,无人机结构和选用材料均满足设计和使用要求。本文设计的电动轻型固定翼农用遥感无人机在结构、材料和性能方面均适用于农业遥感监测。     

Inconel 718合金的磁性复合流体抛光工艺

针对Inconel 718合金材料加工中不断提高的表面质量需求,研究了采用磁性复合流体(Magnetic compound fluid)抛光Inconel718合金材料的加工工艺。根据磁性复合流体抛光原理搭建Inconel718合金抛光实验平台,进行不同抛光方向、抛光时间、抛光转速等工艺参数下的Inconel718合金抛光实验,对工件表面的表面粗糙度、微观形貌进行了测试与分析。实验结果表明:当抛光转速800 r/min,抛光间距3 mm,抛光时间10 min时,Inconel718合金表面粗糙度Ra下降约至0.1μm。