Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 3

年份

2022 1

2021 1

2018 1

关键词

代谢组 1

宏基因组 1

宏转录组 1

昼夜节律 1

经内窥镜肠管 1

重建 1

展开︾

检索范围：

排序：展示方式：

Design, analysis, and neural control of a bionic parallel mechanism

《机械工程前沿（英文）》 2021年第16卷第3期页码 468-486 doi: 10.1007/s11465-021-0640-8

摘要： Although the torso plays an important role in the movement coordination and versatile locomotion of mammals, the structural design and neuromechanical control of a bionic torso have not been fully addressed. In this paper, a parallel mechanism is designed as a bionic torso to improve the agility, coordination, and diversity of robot locomotion. The mechanism consists of 6-degree of freedom actuated parallel joints and can perfectly simulate the bending and stretching of an animal’s torso during walking and running. The overall spatial motion performance of the parallel mechanism is improved by optimizing the structural parameters. Based on this structure, the rhythmic motion of the parallel mechanism is obtained by supporting state analysis. The neural control of the parallel mechanism is realized by constructing a neuromechanical network, which merges the rhythmic signals of the legs and generates the locomotion of the bionic parallel mechanism for different motion patterns. Experimental results show that the complete integrated system can be controlled in real time to achieve proper limb–torso coordination. This coordination enables several different motions with effectiveness and good performance.

关键词： neural control behavior network rhythm motion pattern

HTML PDF 收藏

Bile acids and their effects on diabetes

Cynthia Rajani, Wei Jia

《医学前沿（英文）》 2018年第12卷第6期页码 608-623 doi: 10.1007/s11684-018-0644-x

摘要： Diabetes is a widespread, rapidly increasing metabolic disease that is driven by hyperglycemia. Early glycemic control is of primary importance to avoid vascular complications including development of retinal disorders leading to blindness, end-stage renal disease, and accelerated atherosclerosis with a higher risk of myocardial infarction, stroke and limb amputations. Even after hyperglycemia has been brought under control, “metabolic memory,” a cluster of irreversible metabolic changes that allow diabetes to progress, may persist depending on the duration of hyperglycemia. Manipulation of bile acid (BA) receptors and the BA pool have been shown to be useful in establishing glycemic control in diabetes due to their ability to regulate energy metabolism by binding and activating nuclear transcription factors such as farnesoid X receptor (FXR) in liver and intestine as well as the G-protein coupled receptor, TGR5, in enteroendocrine cells and pancreatic -cells. The downstream targets of BA activated FXR, FGF15/21, are also important for glucose/insulin homeostasis. In this review we will discuss the effect of BAs on glucose and lipid metabolism and explore recent research on establishing glycemic control in diabetes through the manipulation of BAs and their receptors in the liver, intestine and pancreas, alteration of the enterohepatic circulation, bariatric surgery and alignment of circadian rhythms.

关键词： bile acids metabolic memory diabetes circadian rhythm bariatric surgery

HTML PDF 收藏

通过原位观察揭示人体肠道微生物组的重建和动态变化 Article

刘小林, 戴敏, Yue Ma, 赵娜, Ziyu Wang, Ying Yu, Yakun Xu, Huijie Zhang, Liyuan Xiang, He Tian, 税光厚, 张发明, 王军

《工程（英文）》 2022年第15卷第8期页码 89-101 doi: 10.1016/j.eng.2021.03.015

摘要：

人体肠道微生物组主要通过使用粪便样本进行研究，这种做法已经得到了关于胃肠道微生物群落的组成和功能的重要知识。然而，这种对粪便材料的依赖限制了对胃肠道其他位置（原位）微生物动力学的研究，并且粪便样本不能随时获得，这也阻碍了在更精细的时间尺度（如小时）下进行分析。在我们的研究中，我们利用结肠途径经内镜肠内导管（一种最初为粪便微生物群移植开发的技术）每天两次对回盲部微生物组进行采样；然后对这些样品进行宏基因组和宏转录组学分析。从5 名健康志愿者身上共收集了43 份回盲部样本及28 份尿液和粪便样本。在5 名志愿者中分析的回盲部和粪便微生物组被发现在宏基因组分析中相似，但它们的活性基因（宏转录组）被发现高度不同。两种微生物组在泻药暴露后都受到干扰；随着时间的推移，它们表现出与治疗前状态的差异减少，从而证明了作为肠道微生物组的先天特性——恢复力，尽管它们在我们的观察时间窗口内没有完全恢复。白天和夜间对回盲部微生物组的采样显示，在一系列细菌种类和功能途径中存在昼夜节律，特别是与短链脂肪酸产生相关的细菌，如痤疮丙酸杆菌和辅酶A生物合成II。自相关分析和波动分解进一步表明了昼夜振荡的显著周期性。粪便和尿液样本中的代谢组学分析反映出了肠道微生物组的扰动和恢复，表明肠道微生物组对参与宿主健康的诸多关键代谢物的重要贡献。这项研究为人体肠道微生物组及其内在恢复力和昼夜节律以及这些对宿主的潜在后果提供了新的见解。

关键词：昼夜节律重建宏基因组宏转录组代谢组经内窥镜肠管