Mechanical feedback defines organizing centers to drive digit emergence

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A Novel System for Moving Object Detection Using Bionic Compound Eyes

Conventional moving target detection focuses on algorithms to improve detection efficiency. These algorithms pay less attention to the image acquisition means, and usually solve specific problems. This often results in poor flexibility and reusability. Insect compound eyes offer unique advantages for moving target detection and these advantages have attracted the attention of many researchers in recent years. In this paper we proposed a new system for moving target detection. We used the detection mechanism of insect compound eyes for the simulation of the characteristics of structure, control, and function. We discussed the design scheme of the system, the development of the bionic control circuit, and introduced the proposed mathematical model of bionic compound eyes for data acquisition and object detection. After this the integrated system was described and discussed. Our paper presents a novel approach for moving target detection. This approach effectively tackles some of the well-known problems in the field of view, resolution, and real-time processing problems in moving target detection.     

A Novel 3D Microstructural Model for Trabecular Bone: I. The Relationship between Fabric and Elasticity

A novel 3D microstructural model is proposed to investigate the relationship between morphology and mechanical properties of trabecular bone. Open and closed cell geometries were selected with varying volume fractions and degrees of anisotropy that simulate the architectures of human cancellous bone over a broad range of anatomical locations. Finite element models of both cells were developed using beams and shells. Volume fraction and mean intercept length were calculated analytically and the effective elastic tensors were computed with linear tissue properties and periodic boundary conditions

Distinct, but strong relationships were obtained between fabric and the elastic tensors for open and closed cell geometries, which bound the experimental results obtained for human bone and support the relevance of the selected model to address trabecular bone fragility.     

Topological Adaptation of Transmembrane Domains to the Force-Modulated Lipid Bilayer Is a Basis of Sensing Mechanical Force

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The role of nervous system in adaptive response of bone to mechanical loading

Bone tissue is remodeled through the catabolic function of the osteoclasts and the anabolic function of the osteoblasts. The process of bone homeostasis and metabolism has been identified to be co-ordinated with several local and systemic factors, of which mechanical stimulation acts as an important regulator. Very recent studies have shown a mutual effect between bone and other organs, which means bone influences the activity of other organs and is also influenced by other organs and systems of the body, especially the nervous system. With the discovery of neuropeptide (calcitonin gene-related peptide, vasoactive intestinal peptide, substance P, and neuropeptide Y) and neurotransmitter in bone and the adrenergic receptor observed in osteoclasts and osteoblasts, the function of peripheral nervous system including sympathetic and sensor nerves in bone resorption and its reaction to on osteoclasts and osteoblasts under mechanical stimulus cannot be ignored. Taken together, bone tissue is not only the mechanical transmitter, but as well the receptor of neural system under mechanical loading. This review aims to summarize the relationship among bone, nervous system, and mechanotransduction.     

脑源性神经营养因子在大鼠后足切割疼痛中的作用

目的:观察脑源性神经营养因子(BDNF)对大鼠后足切割疼痛的影响。方法:采用纵行切割大鼠后足作为疼痛模型,运用免疫组织化学与免疫荧光双标记方法,观察大鼠后足切割后不同时间点(1-72hr)BDNF在相应节段背根神经节与脊髓内表达的变化。腹腔或鞘内注射BDNF抗体中和内源性BDNF后,以Von Frey尼龙纤维刺激后足行机械痛敏评价。结果:大鼠后足切割后1-24hr内,BDNF在切割侧L42-L5脊髓后角表达明增加,BDNF主要位于后角神经元内与神经末梢,星形胶质细胞与小胶质细胞内未见明显表达;在L42-L5背根神经节,BNDF免疫阳性细胞百分比在切割后1-24hr内也明显增加,增加的主要为大直经神经元;鞘内给予BDNF抗体可明显增加大鼠后足切割后的缩足阈值,而腹腔给予BDNF抗体对大鼠的缩足阈值影响较小。结论:BDNF参与了大鼠后足切割后机械痛敏的过程。     

Formulation Design and Optimization of Novel Taste Masked Mouth-Dissolving Tablets of Tramadol Having Adequate Mechanical Strength

The purpose of this work was to develop novel taste masked mouth-dissolving tablets of tramadol that overcomes principle drawback of such formulation which is inadequate mechanical strength. Tramadol is an opioid analgesic used for the treatment of moderate to severe pain. Mouth-dissolving tablets offer substantial advantages like rapid onset of action, beneficial for patients having difficulties in swallowing and in conditions where access to water is difficult. The crucial aspect in the formulation of mouth-dissolving tablets is to mask the bitter taste and to minimize the disintegration time while maintaining a good mechanical strength of the tablet. Mouth-dissolving tablets of tramadol are not yet reported in the literature because of its extreme bitter taste. In this work, the bitter taste of Tramadol HCl was masked by forming a complex with an ion exchange resin Tulsion335. The novel combination of a superdisintegrant and a binder that melts near the body temperature was used to formulate mechanically strong tablets that showed fast disintegration. A 3² full factorial design and statistical models were applied to optimize the effect of two factors, i.e., superdisintegrant (crospovidone) and a mouth-melting binder (Gelucire 39/01). It was observed that the responses, i.e., disintegration time and percent friability were affected by both the factors. The statistical models were validated and can be successfully used to prepare optimized taste masked mouth-dissolving tablets of Tramadol HCl with adequate mechanical strength and rapid disintegration.     

Understanding structural/functional properties of amidase from Rhodococcus erythropolis by computational approaches

The 3D structure of the amidase from Rhodococcus erythropolis (EC 3.5.1.4) built by homology-based modeling is presented. Propionamide and acetamide are docked to the amidase. The reaction models were used to characterize the explicit enzymatic reaction. The calculated free energy barrier at B3LYP/6-31G* level of Model A (Ser194 + propionamide) is 19.72 kcal mol⁻¹ in gas (6.47 kcal mol⁻¹ in solution), and of Model B (Ser194 + Gly193 + propionamide) is 18.71 kcal mol⁻¹ in gas (4.57 kcal mol⁻¹ in solution). The docking results reveal that propionamide binds more strongly than acetamide due to the ethyl moiety of propionamide, which makes the carboxyl oxygen center of the substrate slightly more negative, making formation of the positively charged tetrahedral intermediate slightly easier. The quantum mechanics results demonstrate that Ser194 is essential for the acyl-intermediate, and Gly193 plays a secondary role in stabilizing acyl-intermediate formation as the NH groups of Ser194 and Gly193 form hydrogen bonds with the carbonyl oxygen of propionamide. The new structural and mechanistic insights gained from this computational study should be useful in elucidating the detailed structures and mechanisms of amidase and other homologous members of the amidase signature family.