拟柱孢藻N8全基因组测序及磷吸收转运通路的比较分析

为从分子水平解析热带特征性蓝藻-拉氏拟柱孢藻(Cylindrospermopsis raciborskii,简称拟柱孢藻)环境适应机制,研究以广东省镇海水库中分离的拟柱孢藻藻株N8为材料,采用PacBio单分子实时测序技术(Single Molecule Real-Time, SMRT)进行测序,并初步进行全基因组特征的比较分析。结果显示拟柱孢藻N8全基因组大小为3.857 Mb, GC含量为40.13%,预测编码基因个数为3598个,在COG、KEGG和GO数据库中注释到的基因数分别为2429、1664和2244个。N8藻株与美国国立生物技术信息中心(NCBI)上公布的27株拟柱孢藻基因组大小和GC含量基本一致,但N8的编码基因数最多。基于拟柱孢藻全基因组单拷贝基因的系统进化树表明N8藻株与韩国藻株GIHE 2018的亲缘关系最近。N8藻株的基因组中未发现拟柱孢藻毒素(CYN)和石房蛤毒素(STX)合成酶基因簇,表明该藻株不产蓝藻毒素CYN和STX。对N8藻株和其他7藻株的磷吸收转运通路比较分析表明,这些藻株均拥有较为完整的磷吸收转运基因(双组分调节系统、低亲和力无机磷转运基因、高亲和力无机磷转运系统、有机磷酸盐转运复合体、C-P裂解酶和碱性磷酸酶),表明拟柱孢藻具有灵活利用环境中不同形态磷源的潜能;而不同藻株间的基因拷贝数和排列顺序存在差异,如拟柱孢藻N8基因组中有2个C-P裂解酶复合体蛋白phnF和phnM,其余7株拟柱孢藻则只有1个,表明拟柱孢藻存在株系特异性。N8藻株为中国首株公开完成全基因组测序数据的拟柱孢藻,对其基因组分析和磷吸收转运通路的解析将有助于阐明华南地区拟柱孢藻水华优势形成的分子机制。

病毒性肝炎患者血清转运铁蛋白含量分析

本文用放射免疫分析法检测了１１９例病毒性肝炎患者血清转运铁蛋白水平。结果显示，各型病毒性肝炎血清转运铁蛋白含量与正常人组相比均下降，且有随病情严重程度增加，血清转运铁蛋白有明显下降的趋势。

微波辐照对线粒体转录因子A(Tfam)转运的抑制作用

为了验证微波辐照对线粒体转录因子A(Mitochondrial transcription factorA,Tfam)转运的抑制作用,本实验成功构建了Tfam表达载体Tfam-pTNT,并将其转入兔网织红裂解液中转录翻译成Tfam的前体蛋白pre-Tfam,并用同位素S35 methionine标记。将原代培养的大鼠大脑皮层神经元暴露于微波15min后,于辐照后0h、6h、12h、24h、48h等五个时相点提取活性线粒体。通过转运分析(Import assay),结果发现,微波辐照明显引起大脑皮层神经元线粒体Tfam前体蛋白pre-Tfam从胞浆向线粒体内的转运障碍,而且呈时间依赖效应。本实验证实了微波辐照能显著抑制Tfam的转运,揭示了微波引起神经元能量代谢障碍的新机制。

慢性高眼压大鼠视网膜谷氨酸转运体GLAST mRNA表达的改变

目的探讨大鼠视网膜M櫣ller细胞谷氨酸转运体GLASTmRNA在高眼压下的改变。方法24只Wistar大鼠24眼行三条表层巩膜静脉结扎制作高眼压模型,阳性对照组24眼为实验组的对侧眼,行假手术处理。24只大鼠随机平均分为3组,分别于眼压升高后第1周、第5周、第9周处死,提取视网膜总RNA,行逆转录多聚酶链反应(reversetranscriptasepolymerasechainreacton,RTPCR),对其视网膜GLASTmRNA进行半定量分析。结果表层巩膜静脉结扎可使大鼠眼压持续中度升高至少2个月,实验组视网膜中GLASTmRNA水平在各观察时间点内(0.535±0.067,0.259±0.101和0.301±0.064)均明显低于对照组(0.954±0.031,0.885±0.067,0.909±0.508),差异有显著性(P<0.05)。结论大鼠在持续的高眼压下视网膜M櫣ller细胞谷氨酸转运体GLASTmRNA水平明显下降,而GLAST的表达减少可能是造成视网膜谷氨酸水平增高,从而导致青光眼视神经损伤的一个重要的因素。

Motion Analysis of Fiber Band in Compact Field of Compact Spinning

The technological process of compact spinning and the compact procedure of fiber band in compact field are briefly illustrated. The motions of fiber band in compact field are discussed theoretically from which tilting angle of suction slot in profile tube, additional twists created by fiber band’s rotating around its own axis and ultimate twists in compact yarn are deduced accordingly. The existence of additional twists is also verified through experiments.

Mechanism Design and Motion Analysis of Heavy⁃Load Transfer Robot with Parallel Four⁃Bar Mechanism

Heavy-load transfer robots are widely used in automobile production and machinery manufacturing to improve production efficiency.In order to meet the needs of large billet transfer,a 4-DOF transfer robot is designed in this paper,which consists of parallel four-bar mechanisms.The Jacobian matrix referring to the mapping matrix from the joint velocity to the operating space velocity of the transfer robot can be solved by the differential-vector method.The mean value of the Jacobian matrix condition number in the workspace is used as the global performance index of the robot velocity and the optimization goal.The constraint condition is established based on the actual working condition.Then the linkage length optimization is carried out to decrease the length of the linkage and to increase the global performance index of velocity.The total length of robot rods is reduced by 6.12%.The global performance index of velocity is improved by 45.15%.Taking the optimized rod length as the mechanism parameter,the distribution of the motion space of the transfer robot is obtained.Finally,the results show that the proposed method for establishing the Jacobian matrix of the lower-mobility robot and for the optimization of the rods based on the velocity global performance index is accurate and effective.The workspace distribution of the robot meets the design requirements.

A Model for Analyzing the Transshipment Competition Relationship Between the Port of Hong Kong and the Port of Kaohsiung

The transshipment is an important issue in the current marine transportation. This paper constructed a mathematical programming model to elaborate the transshipment port selection for the shipping company. This model is tested by the data collected from the ports of Hong Kong and Kaohsiung. The results show that this model can be used to explain the transshipment competition relationship between the ports of Hong Kong and Kaohsiung well. A sensitivity analysis was also executed. The sensitivity analysis results showed that both the port of Hong Kong and Kaohsiung should decrease the charges of port and increase the effi- ciency of loading and discharging. Based on the sensitivity analysis results, some interesting conclusions and helpful suggestions were obtained for the managers of the ports of Hong Kong and Kaohsiung to improve their port management.

Simulation and Analysis of Fiber Motion in Condensing Zone of Compact Spinning with Lattice Apron

To get fiber motion in condensing zone of compact spinning,velocity of this area is achieved by simulation,and then a bead-elastic rod fiber model is established.Based on simulation and dynamic analysis on this zone,governing equations are constructed and Runge-Kutta approach is used.Lastly,trajectories of fibers are calculated by specially designed Matlab procedure according to the principles mentioned above.Results show that fiber motions at different initial positions are different;X-axis velocity component makes fibers gathering on sides of suction slot;Y-axis airflow gets fibers gradually close and then stick to the surface of lattice apron.Fiber motions also reflect that the compact spinning process in condensing zone can be divided into three parts:fast convergence zone,adjustment convergence zone,and steady convergence zone.

Efficacy and safety of the heated gel mattress for prevention of hypothermia in preterm infants during intra-hospital transport： a meta-analysis

Objective： To evaluate the efficacy and safety of the heated gel mattress for prevention of heat loss on preterm infants with hypothermia during the transport systematically and objectively. Methods： Systematic searches on PubMed, EM- BASE, Cochrane Library, Web of Science, CBM, CNKI, Wanfang and VIP were performed for randomized controlled trials （RCTs） or quasi-RCTs which explored the effects of heated gel mattress on prevention of hypothermia in premature infants relative to conventional alternatives. Studies were screened according to inclusion and exclusion criteria, extracted data and assessed quality. Then, meta-analysis and trial sequential analysis were performed by RevMan 5.3 and TSA vO.9 software developed at the Copenhagen Clinical Trials Center in Denmark, independently. Results： This systematic review included 10 studies which comprised 7 RCTs and 3 quasi-RCTs, encompassing 773 patients. The results of meta-analysis showed that in heated gel mattress group admission temperature on neonatal intensive care unit （SMD, 0.63; 95% CI, 0.40 to 0.87; P = 0.00）, incidence of hypothermia （RR, 0.73; 95% CI, 0.57 to 0.93; P = 0.01） and hyperthermia （RR, 1.82; 95% CI, 1.31 to 2.541 P = 0.00） compared with the control group had significantly statistical difference; however, there was no significant difference in admission temperature on exothermic mattresses or TransWarmer mattress group, mortality, sepsis, retinopathy of prematurity, intraventricular hemorrhage Ⅲ/Ⅳ between two groups, trial sequential analysis confirmed that the pooled results of admission temperature on neonatal intensive care unit and hyperthermia were stable and reliable; but the combination of low-temperature incidence and mortality indicators suggested that the sample size was insufficient. Conclusion： Heated gel mattress is a safe and effective re- warming intervention that can improve body temperature of hypothermic preterm infants during transport, reduce the incidence of hypothermia and does not increase the incidence of morbidity and complications. However, it is recommended that clinical monitoring of body temperature should be performed dynamically to decrease the potential risk of high fever. In addition, due to the limitation of quantity and quality of included studies, its cost-effectiveness and far-reaching influence on long-term follow-up outcomes need further evaluation through clinical multicenter, large sample, and high-quality research.

Correlation analysis between serum β2-MG and sodium/iodide symporter in patients with thyroid carcinoma

Objective： The aim of our study was to investigate the correlation between the expression of sodium/iodide symporter, serum levels of β2-MG and prognosis of thyroid carcinoma patients. Methods： Ninty-five cases with thyroid carcinoma, using enzyme-linked immunosorbent assay with double-antibody sandwich to detect the serum β2-MG levels and immunehistochemistry to detect NIS expression of thyroid cancer tissue. Results： Thirty-seven cases showed positive expression of sodium/iodide symporter （38.9%） and 30 cases showed positive expression of β2-MG （31.57%）. There were significant differences of NIS expression （X2 = 8.207, P = 0.017） and β2-MG expression （X2 = 10.121, P = 0.006） between different pathological types of thyroid carcinoma, but there was no correlation between the positive rate of the two research groups （r = -0.546, P = 0.633）. The significant differences was observed in expression of sodium/iodide symporter （X2 = 9.272, P=0.002） and expression of β2-MG （X2 = 4.441, P = 0.035） between the group with neck lymph node metastasis and the group without neck lymph node metastasis and both positive rate was significantly negatively correlated （r = -1.000, P = 0.000）. The significant differences was observed in expression of sodium/iodide symporter （X2 = 9.272, P = 0.002） and expression of β2-MG （X2 = 3.867, P = 0.043） between the group with distant organ metastasis and the group without distant organ metastasis （X2 = 11.985, P = 0.001） and both positive rate was significantly negatively correlated （r = -1.000, P = 0.000）. Conclusion： There are significantly negatively correlated between neck lymph node metastasis, distant organ metastasis and expression of sodium/iodide symporter and expression of β2-MG. Thyroid cancer lymph node and distant organ metastasis, the tumor tissue NIS expression and serum levels of β2-MG is significantly negatively correlated. The detection of serum β2-MG provides clinical reference value for the effects on radionuclide therapy and prognosis assessment of thyroid carcinoma. Serum β2-MG levels is negatively correlated with prognosis in thyroid cancer patients.

Kinematic Analysis of Persian Joint Using 3D Rotation Matrix

This paper has been done on study kinematic problem of Persian joint in a general way. In this study, instead of using simulation analysis method as in the previous researches, the 3D rotation matrix method is applied to present the relationship of angular velocities of input shaft and output shaft. The result shows that when the angle between intersecting shafts changes from 0 to 135°, the angular velocity is maintained constant. This new result completely matches with analysis from kinematic simulation of this mechanism. The obtained result is an important base to solve dynamic problem in order to develop the applicability of this joint in reality.

A gait generation and transition method for quadruped walking machine

In nature, quadrupeds as horses or cats change their gait to be suited to their motion speed. This fact is very important to realize smooth motion with different gaits. In this article a method of the gait transition for the quadruped walking machine is proposed. With analyzing the accustomed gaits of quadruped, some standard gaits and the relationships between duty factor and the phasic differences of the legs corresponding to the first leg could be concluded. With this, the gaits transferring could be continuous. Besides, celerity and on line method for generation and modifying gaits is studied, which can make the robot have a smooth motion to adapt the uncharted rough terrain.

Movement analysis on steel wire rope of continuous conveyor with disc-tube assembly

The steel wire rope of continuous conveyor with disc-tube assembly is droved by the driving wheel. When the driving wheel rotates, the gear is combined to the con- nection disc in turn, promoting the connection disc to move in succession. Turning the whirling torque of driving wheel into the straight-line traction force. When the steel wire rope is winded by the driving wheel some winded along the circumference, others winded along the straight line. Used motion subject law, this article analyses the change of the velocity and the acceleration of the steel wire rope in the straight movement, and observe the mathematics’ model of velocity and acceleration.

Research on Turning Characteristics of Helicopter Ground Motion

In the passive turning state,the helicopter turns through the tail rotor force and the friction of the ground to the tire.In practice,it is found that the helicopter will turn difficultly under low aircraft ground speed or static state.This paper takes a certain type of helicopter as the research object,and establishes the dynamic model of helicopter ground turning motion based on the basic theory of dynamics.This model takes into account the six-degree-of-freedom motion model of the helicopter body,the motion model of the landing gear buffer,the tire mechanics model and the friction characteristics of the strut friction disc.The dynamic simulation of the helicopter right angle turn and static turn is carried out,and the influence of parameters such as tail rotor pull,taxi speed,tail wheel stability distance on the dynamic response of the turn is studied.The results show that under the same ground taxing speed,the tail wheel angle increases with the increase of tail rotor force.When the tail rotor force is the same,the tail wheel angle increases with the increase of ground taxing speed.When the helicopter is completely static,it is the most difficult to turn,which requires much bigger force of the tail rotor to turn.In addition,the change of the stability distance of the tail wheel has an obvious influence on the turning.When the stability distance is doubled,the tail rotor force will be reduced by 30%to the same angle of the tail wheel.

Molecular cloning and structural analysis of human norepinephrine transporter gene(NETHG)

A cDNA molecule encoding a major part of the hu-man Norepinephrine transporter(hNET) was synthesized by means of Polymerase Chain Reaction(PCR) technique and used as a probe for selecting the human genomic NET gene. A positive clone harbouring the whole gene was ob-tained from a human lymphocyte genomic library through utilizing the "genomic walking" technique. The clone, des-ignated as phNET, harbours a DNA fragment of about 59 kb in length inserted into BamH Ⅰ site in cosmid pWE15.The genomic clone contains 14 exons encoding all amino acid residues in the protein. A single exon encodes a dis-tinct transmembrane domaill, except for transmembrane domain 10 and 11, which are encoded by part of two ex-ons respectively, and exon 12, which encodes part of do-main 11 and all of domain 12. These results imply that there is a close relationship between exon splicing of a gene and structural domains of the protein, as is the case for the human γ-aminobutyric acid transporter(hGAT) and a number of other membrane proteins.