基于Electrooculogram的眼动信息识别

眼动电图（Electrooculogram, EOG）是无创记录眼球运动的一种有效方法,它能记录到眼球的任何微小动作,甚至闭眼状态下眼球的动作.为能自动识别其所包含的眼动信息,本文从时域分析出发,提出了幅度阈值法和微分法2种眼动信息识别方法,并重点实现了微分算法.微分法识别眼动信息的基本思想是,对基线调整、平滑处理后的EOG信号进行求一阶微分的运算,然后对微分结果求极值,最后根据不同眼动模式下EOG波形的微分极值分布特征进行眼动信息的识别.通过该法对19个EOG样本中所包含的眼动信息的识别,最终得到了总误判率小于0.02的结果.最后,本文还给出了从眨眼EOG波形分析得来的眨眼时的眼球动作的现象.     

<i>miR-103-3p</i> regulates the differentiation of bone marrow mesenchymal stem cells in myelodysplastic syndrome

The pathogenesis of myelodysplastic syndrome (MDS) may be related to the abnormal expression of microRNAs (miRNAs), which could influence the differentiation capacity of mesenchymal stem cells (MSCs) towards adipogenic and osteogenic lineages. In this study, exosomes from bone marrow plasma were successfully extracted and identified. Assessment of miR-103-3p expression in exosomes isolated from BM in 34 MDS patients and 10 controls revealed its 0.52-fold downregulation in patients with MDS compared with controls (NOR) and was downregulated 0.55-fold in MDS-MSCs compared with NOR-MSCs. Transfection of MDS-MSCs with the miR-103-3p mimic improved osteogenic differentiation and decreased adipogenic differentiation in vitro, while inhibition of miR-103-3p showed the opposite results in NOR-MSCs. Thus, the expression of miR-103-3p decreases in MDS BM plasma and MDS-MSCs, significantly impacting MDS-MSCs differentiation. The miR-103-3p mimics may boost MDS-MSCs osteogenic differentiation while weakening lipid differentiation, thereby providing possible target for the treatment of MDS pathogenesis.     

确定凸轮廓线曲率半径的数值微分法

应用数值微分法计算凸轮廓线坐标的一、二阶导数,代入微积分学中曲率半径公式,即得凸轮廓线的曲率半径。用两次计算曲率半径值的办法给出了计算误差的估计式。计算表明该方法在计算精度上足以满足工程上的需要,并能避免烦琐的公式推导。当凸轮廓线由离散值给出时,各种解析法不便应用,采用本法更有其独特的优点。该方法不但适用于推杆为直动、摆动、平底等各种情形,且便于编制各种情况下统一的计算程序。     

Cell-cell communication between mouse mammary epithelial cells and 3T3-L1 preadipocytes: effect on triglyceride accumulation and cell proliferation.

Interaction between parenchyma and stroma is essential for organogenesis, morphogenesis, and differentiation. Mammary gland has being the chosen model for developmental biologist because the most striking changes in morphology and function take place after birth. We have demonstrated a regulation of triglyceride accumulation by protein factors synthesized by normal mouse mammary gland epithelial cells (NMMG), acting on a cell line, 3T3-L1, long used as a model for adipogenesis. In this paper, we demonstrate that this inhibitory effect seems to be shared by other cells of epithelial origin but not by other cell types. We found a regulation of cell proliferation when NMMG cells are cultured in the presence of conditioned media from Swiss 3T3 or 3T3-L1 cells. We found a possible point of regulation for the mammary factor on a key enzyme of the lipid metabolic pathway, the glycerol-3-phosphate dehydrogenase. The inhibitory factor seems to have an effect on this enzyme's activity and reduces it. The results presented herein contribute to the understanding of cell-cell communication in a model of a normal mammary gland.     

C功能刀补在经济型CNC系统中的实现

提出了一种独特而新颖的C功能刀补实现方法,将复杂的函数运算转化为简单的加、减运算,算法简单实习,从而解决了C功能刀补在经济型CNC系统中的实现实现问题.     

Super-twisting sliding mode differentiation for improving PD controllers performance of second order systems

Designing a proportional derivative (PD) controller has as main problem, to obtain the derivative of the output error signal when it is contaminated with high frequency noises. To overcome this disadvantage, the supertwisting algorithm (STA) is applied in closed-loop with a PD structure for multi-input multi-output (MIMO) second order nonlinear systems. The stability conditions were analyzed in terms of a strict non-smooth Lyapunov function and the solution of Riccati equations. A set of numerical test was designed to show the advantages of implementing PD controllers that used STA as a robust exact differentiator. The first numerical example showed the stabilization of an inverted pendulum. The second example was designed to solve the tracking problem of a two-link robot manipulator.     

Bones Morphogenic Protein‐4 and retinoic acid combined treatment comparative analysis for in vitro differentiation potential of murine mesenchymal stem cells derived from bone marrow and adipose tissue into germ cells

Nowadays, infertility is no longer considered as an unsolvable disorder due to progresses in germ cells derived from stem lineage with diverse origins. Technical and ethical challenges push researchers to investigate various tissue sources to approach more efficient gametes. The purpose of the current study is to investigate the efficacy of a combined medium, retinoic acid (RA) together with Bone Morphogenic Protein‐4 (BMP4), on differentiation of Bone Marrow Mesenchymal Stem Cells (BMMSCs) and adipose‐derived mesenchymal stem cells (ADMSCs) into germ cells. Murine MSCs were obtained from both Bone Marrow (BM) and Adipose Tissue (AT) samples and were analyzed for surface markers to get further verification of their nature. BMMSCs and ADMSCs were induced into osteogenic and adipogenic lineage cells respectively, to examine their multipotency. They were finally differentiated into germ cells using media enriched with BMP4 for 4 days followed by addition of RA for 7 days (11 days in total). Analyzing of differentiation potential of BMMSCs‐ and ADMSCs were performed via Immunofluorescence, Flowcytometry and Real time‐PCR techniques for germ cell‐specific markers (Mvh, Dazl, Stra8 and Scp3). Mesenchymal surface markers (CD90 and CD44) were expressed on both BMMSCs and ADMSCs, while endothelial and hematopoietic cell markers (CD31 and CD45) had no expression. Finally, all germ‐specific markers were expressed in both BM and AT. Although germ cells differentiated from ADMSCs showed faster growth and proliferation as well as easy collection, they significantly expressed germ‐specific markers lower than BMMSCs. This suggests stronger differentiation potential of murine BMMSCs than ADMSCs.     

Dynamic programming approach for analyzing delayed product differentiation

Cutting down lead-time and expanding product variety are two essential means to improving customer service. To recognize the specific requirements of markets, many computer companies are adopting a build-to-order (BTO) policy. Under this policy, original equipment manufacturing (OEM) companies that are component suppliers for these computer companies are compelled to offer their components near the end-users within shortened lead-times. This forces the OEM companies to develop their branches and warehouses that can implement some assembly operations for the products that have been semifinished at the central company. The main problem faced by these OEM companies is determining the differentiation point of the production processes where the products are diversified at the central company. In this paper, a dynamic approach is proposed to construct an analysis framework for this problem. This approach can deal with situations that do not differentiate all products at the same time. This is especially relevant when the investment cost or processing cost for process normalization and modularization of process redesigning is dependent on products in common parts or sets or on their differentiation sequence. This approach is different from the results claimed in previous research. An example of a real case is then applied to illustrate the applicability of the model.     

Protein kinase C and mitogen-activated protein kinase signalling in oligodendrocytes

Oligodendrocytes (OL) play a significant physiological role in the central nervous system by creating the myelin sheath that allows for the efficient conduction of nerve impulses. Therefore, it is important to understand which signalling cascades define the proliferation, differentiation, survival, and myelin formation potential of these cells. Currently, much of the knowledge in this field has focused on two sets of protein kinase signalling molecules: Protein kinase C (PKC) and the mitogen-activated protein kinases (MAPKs). The roles of these kinases in OL are complex, and appear to be highly dependent on the developmental stage of the OL. Even so, some broad conclusions can be drawn from the multitude of experiments conducted on the roles of PKC and MAPKs in OL. For instance, PKC appears to have a proliferative effect on immature OL, while at the same time having an inhibitory effect on OL differentiation. In mature OL, the effects of PKC include increased process extension and myelin formation. The extracellular signal-regulated (ERK) members of the MAPK family also appear to increase process extensions in mature OL. On the other hand, the c-Jun N-terminal kinase (JNK) and p38 kinase members of the MAPK family appear to regulate apoptotic events in OL.     

From linear to nonlinear control means: a practical progression

With the rapid advance of digital control hardware, it is time to take the simple but effective proportional-integral-derivative (PID) control technology to the next level of performance and robustness. For this purpose, a nonlinear PID and active disturbance rejection framework are introduced in this paper. It complements the existing theory in that (1) it actively and systematically explores the use of nonlinear control mechanisms for better performance, even for linear plants; (2) it represents a control strategy that is rather independent of mathematical models of the plants, thus achieving inherent robustness and reducing design complexity. Stability analysis, as well as software/hardware test results, are presented. It is evident that the proposed framework lends itself well in seeking innovative solutions to practical problems while maintaining the simplicity and the intuitiveness of the existing technology.     

三油叶轴承静载平衡位置求解

将差分法和优化设计中的坐标轮换法相结合对以三油叶轴承为代表的多瓦块轴承的静载轴心位置进行计算，并结合计算机进行求解。     

Single-cell RNA sequencing reveals classical monocytes are the major precursors of rat osteoclasts

To dissect which subset of bone marrow monocyte is the major precursor of osteoclast, 3-month-old rat bone marrow was obtained for single-cell RNA sequencing. A total of 6091 cells were acquired for detailed analysis, with a median number of 1206 genes detected per cell and 17,959 genes detected in total. A total of 19 cell clusters were recognized, with the main lineages identified as B cells, Granulocytes, Monocytes, T cells, Erythrocytes and Macrophages. Monocytes were further divided into classical monocytes and non-classical monocytes. Compared with non-classical monocytes, classical monocytes highly expressed osteoclast differentiation related genes Mitf, Spi1, Fos and Csf1r. Additionally, biological processes of classical monocytes were related to osteoclast differentiation. qPCR revealed differentially expressed genes of classical monocytes played a role in osteoclast differentiation. In conclusion, classical monocytes were identified as the main precursors of osteoclasts in rats, and may contribute to osteoclast differentiation by regulating S100a4, S100a6, S100a10, Fn1, Vcan and Bcl2a1. The results of this study contribute to the understanding of the origin of osteoclasts and may provide potential biomarkers for early diagnosis of bone metabolic diseases, as well as molecular and cellular targets for clinical intervention in bone metabolic diseases.     

New insights into the cellular makeup and progenitor potential of palatal connective tissues

The present study investigated the regenerative potential of connective tissues harvested from two palatal areas widely used as donor sites for muco‐gingival surgical approaches. Connective tissue grafts (CTGs) were obtained by de‐epithelialisation of a free gingival graft (deCTG) and by a split flap approach from a previous donor site (reCTG). Two types of mesenchymal stem cell (MSCs) were isolated and were named de‐epithelialised MSCs (deMSCs) and re‐entry MSCs (reMSCs). The cells were characterised and cellular functionality was investigated. CTGs were evaluated using immunohistochemical and ultrastructural approaches. No significant differences were observed regarding the frequency of colony‐forming unit‐ fibroblasts, migration potential, and population doubling time between the two cell lines (p > 0.05). Both cell lines showed positivity for CD105, CD73, CD90, and CD44 and negative expression for CD34/45, CD14, CD79a, and HLA‐DR. MSCs from both cell lines successfully differentiated into osteogenic, adipogenic, and chondrogenic lineages. Cells expressing antigens characteristic of CD34+ stromal cells (CD34+, αSMA?, CD31?) were traced in both CTGs. Ultrastructural analysis highlighted the presence of putative progenitors, namely fibroblasts,—in the pericapillary regions and in remote regions of the lamina propria‐ and pericytes—surrounding the capillaries. This study provides supplementary arguments for the use of CTG grafts in clinical practice due to the presence of putative progenitor cell. However, results were inconclusive regarding clinical decision‐making to determine optimal harvesting area. Prior harvesting in the donor area did not appear to alter the regenerative capabilities of the connective tissue.     

Visceral regeneration in holothurians.

Holothurians, or sea cucumbers, exhibit two processes that have intrigued biologists for decades: autotomy and regeneration. Autotomy includes the loss of body parts by evisceration or fission, and regeneration is the extraordinary process by which the lost organs are replaced. In this article, we review the literature on evisceration, transection, and visceral regeneration in holothurians and compare these processes in different orders and lower taxa. Focusing mainly on the digestive tube, we analyze regeneration from a cellular perspective, considering especially the origin, migration, and proliferation of the cellular components of the regenerated organ. The data highlight the most interesting aspects of holothurian regeneration and indicate those critical problems requiring new information and new approaches.     

基于全微分法解平面尺寸链及孔系坐标公差的计算通式

在工艺尺寸链中,平面尺寸链较为繁杂,在箱体孔系、斜孔加工及装配工艺中常需解算。本文以微分学原理对尺寸公差进行系统处理,不仅简化了分析计算,而且由于同时考虑了常被忽略的角度误差,极大的提高了计算的精确性和合理性,并由此首次推导出孔系坐标公差的极值法公式和概率法公式,极大的方便了机制工艺人员的工艺工装设计。     

基于全微分法的平面尺寸链求解

以微分学原理对平面尺寸链进行求解，简化了分析和计算过程，同时考虑了常被忽略的角度误差，提高了计算的精确性和合理性，给出了相应较为简洁的计算公式，并讨论了公差带的分布，方便了工艺人员的工艺工装设计。     

CDK5 inhibition promotes osteoblastic differentiation of MSCs and blocks the migration of osteosarcoma MG-63 cells

CDK5 belongs to the cyclin-dependent kinase family. CDK5 is multifunctional and plays an important role in neural differentiation. However, the role of CDK5 in osteoblastic differentiation remains unclear. The present study investigated functions and molecular mechanism of CDK5 in osteoblastic differentiation. It was found that, CDK5 inhibition promoted the expression of Runx2, ALP, OCN and OPN of MSCs and the mineralization of MC-3T3E1 cells and MSCs. CDK5 inhibition enhanced the development of F-actin, nuclear localization of β-catenin and YAP, as well as the expression of RMRP RNA. When F-actin was suppressed by Blebbistatin, the nuclear localization of YAP and β-catenin, and expression of RMRP RNA as well as Runx2 and ALP were decreased. These indicate Seliciclib promotes osteoblastic differentiation mainly by F-actin. Moreover, Seliciclib also suppressed the migration of MG-63, suggesting a potential application for Seliciclib in bone defect repair and inhibition of the migration of osteosarcoma cells after osteosarcoma surgical resection.     

Phase determination and microstructure of oxide scales formed on steel at high temperature

Even in simple low-alloy steels the oxide scales that form during hot working processes are often a complex mixture of three iron oxide phases: haematite, magnetite and wüstite. The mechanical properties, and hence descalability, are intimately linked with phase distribution and microstructure, which in turn are sensitive to both steel composition and oxidation conditions. In this study electron backscatter diffraction in the SEM has been used to characterize the microstructures of oxide scales formed on two compositions of low-alloy steel. The technique can unambiguously differentiate between the candidate phases to provide the phase distribution within the scale. This is used to investigate grain orientation relationships both within and between phase layers. It has been found that the strength of the orientational relationship between the magnetite and wüstite layers is dependent on steel composition, and in particular Si content. In a low-Si (0.01 wt%) alloy only a very weak relationship was found to exist for a range of oxidation temperatures (800–1000 °C), whereas for the higher Si (0.37 wt%) alloy a strong relationship was observed under the same oxidation conditions. These orientational relationships are particularly important because, in this temperature range, the majority of oxide scale growth occurs at the magnetite/wüstite interphase boundary.     

齿轮五杆机构位置误差分析

文中针对齿轮五杆机构的位置误差方面的问题提出了一种全微分法,并对其进行了分析,通过对机构位置方程组求全微分得到其误差方程组,进而解出位置误差。与其他方法相比,该方法简便、直观,能够很好地确定出位置误差的影响因素,还可对其做进一步的定性分析。