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In the era of knowledge economy, acquiring top talent has become the key to competitiveness for urban and regional areas. As the representatives of top talent, CAS(Chinese Academy of Sciences) and CAE (Chinese Academy of Engineering), Yangtze River Scholars, and Distinguished Young Scholars are important for breakthroughs in and promotion of competitiveness in urban science and technology competitiveness. Taking the core area of the Yangtze River Delta as an example, based on the list of CAS and CAE, Yangtze River scholars, and Distinguished Young Scholars in the previous year, through a resume analysis method, a resume database of 1,878 highly-talented individuals was constructed. Considering the urban scale, this study explores the law of social space flow and its influencing factors, using the ArcGIS spatial analysis and social surveys. It aims to identify the urban and regional where top innovative talent gathering, and provide inspiration for the construction of a regional network. The conclusions are as follows: (1) The first career choice of high-level talent has a significant spatial proximity orientation, which manifests in two aspects. First, local emotional traction is strong, and the migration from one's place of birth to the place of employment is mainly local or migration to the neighboring. Second, owing to the relationships developed during education, the historical correlation between high-level talent employment and schooling is strong. (2) The geographical flow of re-employment has two characteristics, network correlation and spatial proximity flow. The former is characterized by the long-distance siphoning to first-tier cities, such as Beijing, Guangzhou, and Shenzhen from non-first-tier cities in the core area of the Yangtze River Delta, as well as the significant circulation between cities that are not adjacent in space but have similar characteristics. The latter is characterized by the fact that spatial proximity was still retain within the core area of the Yangtze River Delta. (3) The pursuit of individual interests by high-level talent and the urban comprehensive environment jointly shape the network correlation phenomenon of high-level talent flow. High-level talent pays most attention to economic level, innovation support, development opportunities, and emotional support, while the strength of the urban "talent magnetic field" is ultimately determined by the urban comprehensive environment, comprising the economy, policies, innovation, and social environment.

In recent years, offshore wind power has developed rapidly. It is the most effective way to transmit the wind power far away from the coast through the voltage source converter based high voltage direct current (VSC-HVDC) transmission system. The offshore wind power is usually transmitted by cable, which makes the fault characteristics of VSC-HVDC transmission system more complex than that of overhead transmission system. Based on a symmetrical monopole topology of two-terminal VSC-HVDC offshore wind power transmission project, the mathematical model of the transmission system which contains cables and VSC-HVDC system is simplified. The fault characteristics under typical faults such as single-phase grounding of AC system at converter valve side and single pole grounding of DC cable line are analyzed. Based on the superposition principle, the fault mechanism is analyzed in detail. According to the fault sources of different fault types, different fault circuits are equivalent. The complex influence of the significant capacitance effect of long-distance cables on the fault characteristics of VSC-HVDC systems is obtained. A real time digital simulation model of offshore wind power transmission system through VSC-HVDC is built. The fault mechanism is verified through simulation analysis.

Objective To investigate the stress-strain distribution of magnesium alloy meshes with different thickness during bone healing by three-dimensional finite element analysis in order to provide a reference for the design of personalized magnesium alloy mesh. Methods After the cone-beam computed tomography (CBCT) data of a patient with tooth loss of C2-D2 and large alveolar defect were extracted, three-dimensional reconstruction was performed on the bone defect area. Three-dimensional finite element models of bone implant material and magnesium alloy meshes with different thickness were designed, and their stress-strain distributions were analyzed. Results The strain and stress showed a decreasing trend with the increase of the thickness of magnesium alloy mesh. During the process of bone healing, the stress of the bone implant material was gradually increased while the strain was gradually decreased. The strain of immature and mature bone was less than the strain at break. The stress was decreased first and then increased in the degradation of magnesium alloy mesh. Conclusion Magnesium alloy mesh of 0.3 and 0.4 mm thickness can only bear a small load, and can't meet the need of large area guided bone regeneration (GBR). The maximum equivalent stress of 0.5 mm-thickness magnesium alloy mesh is within the safe range, and the mesh has enough strength in the process of degradation, and can guide good bone healing and meet the clinical needs of GBR.

In view of problem that there is a big difference between calculated load and real load when roof load is estimated or thin plate theory model is used to study mechanical characteristics of advanced support at present, a new type of roadway advanced support was designed, and the mechanical characteristics of the advanced support were studied according to spatial effect of roadway excavation. Based on spatial effect, the coupling mechanism between advanced support and surrounding rock of roadway was studied, and coupled mechanical model of the advanced support and surrounding rock was built. The research results show that along the direction of roadway excavation, the roof load borne by the roadway advanced support decreases gradually, the closer to the working face, the greater the roof load is, and the front end strength of the advanced support is higher than that of the back end. The support timing of the advanced support is very important for the stability of roadway roof, the closer the advanced support is arranged to the roof of working face, the smaller deformation of the roadway roof will be; while the larger the load borne by the advanced support is, the higher the strength required will be.

Objective: To investigate the expressions of T cell receptor (TCR) signaling CD3γ, CD3δ and CD3epsilon chains in T cells from peripheral blood mononuclear cells (PBMCs) in lead-poisoned workers after chelate treatment., Methods: The expression levels of CD3γ, CD3δ and CD3epsilon mRNAs in PBMCs from 16 lead-poisoned workers before and after chelate treatment and 9 healthy individuals were detected by real-time quantitative PCR. The β2-microglobulin gene (β2M) was used as an endogenous reference. Relative mRNA levels were calculated by the 2(-δCt)×100%. Spearman correlation analysis was used to estimate the correlations of different gene expression levels between healthy individuals and the patients as well as before and after the treatment., Results: The CD3γ mRNA level in the lead-poisoned workers before and after chelate treatment has no significant difference as compared with that of the healthy individuals. The expression levels of CD3δ mRNA in the lead-poisoning workers before and after chelate treatment were remarkably lower than that of the healthy individuals. After chelate treatment, the CD3δ mRNA level in the lead-poisoned workers was lower than that before treatment. The CD3epsilon mRNA level in the lead-poisoned workers before treatment was obviously higher than that of the healthy individuals, while the expression level of CD3epsilon mRNA decreased after chelate treatment. There were no evident correlations between CD3γ and CD3δ, CD3γ and CD3epsilon, CD3δ and CD3epsilon mRNAs, while CD3γ and CD3δ, CD3γ and CD3epsilon, CD3δ and CD3epsilon mRNAs had markedly positive correlations in the lead-poisoned workers before chelate treatment, and only CD3δ and CD3epsilon had a significantly positive correlation after the treatment., Conclusion: The expression levels of CD3γ, CD3δ and CD3epsilon mRNAs in the lead-poisoned workers showed varied alterations, which indicated that lead poisoning had an impact on human immunity system and affected different genes in different ways. After chelate treatment, CD3δ mRNA level was still different from that of healthy individuals, which indicated that the function of the immunity system was still abnormal.

Objective: To observe the clinical characteristics and regular patterns of subacute 1, 2-dichloroethane poisoning patients for providing evidences to it's diagnosis, treatment and prognosis., Methods: 51 cases of subacute 1, 2-dichloroethane poisoning analyzed. They were divided into 3 groups according to their main clinical manifestation: group A mainly with intracranial hypertension (n = 25), group B with limbs tremor (n = 18), group C with mental and behavior disorder (n = 8). All cases' clinical symptoms, cranial computer tomography, cerebrospinal pressure (Group A) were observed, the durations of the onset, deterioration, improvement, recovery and whole course of the disease were compared between groups and in each group., Results: In all of 51 cases, only the differences between the deterioration duration of cranial CT and symptom was significantly (t = 2.555, P<0.05), which indicate the deterioration of symptom was earlier than radiological change. The symptom deterioration of group C was the fastest than group A and group B (P<0.00). As to the change of symptom duration, group B's improvement, recovery and whole course was the longest comparing with group A and group C (P<0.05). As to the change of cranial CT duration, group B's recovery duration was the shortest and group A's recovery duration was the longest (P<0.01); group B's whole course was also the shortest and group A's whole course was the longest (P<0.05). The clinical course of symptoms, cranial computer tomography, cerebrospinal pressure (Group A) was compared in each group, in group A, the duration of improvement and whole course of the cranial CT and cerebrospinal pressure change was longer than that of the symptom change (P<0.01), this indicated that group A has longer asymptomatic intracranial hypertension and their cranial radiography recover slowly. In group B, their symptoms (3.94 ± 4.31 days) deteriorated is earlier than cranial CT changes (P<0.05), the recovery (92.39 ± 55.04 days) and whole course of symptom was longer than cranial CT change (all P<0.01). In group C, symptom deterioration was earlier than CT deterioration (P< 0.05)., Conclusion: The clinical characteristic of subacute 1, 2- dichloroethane poisoning is central nervous system damage, it differs according to the different stage of course, the regions and severity of pathology lesions.

To study the attachment, proliferation and differentiation of neural stem cells (NSCs) on surface modified PHBHHx films and to establish the theory of PHBHHx application in NSCs-based brain tissue engineering. PHBHHx film was fabricated by a solution-casting method, and the morphology of the film was observed under scanning electron microscopy(SEM). The films were treated by NaOH or lipase, then the surface hydrophilic property was characterized using water contact angle measurement. NSCs were isolated from the cerebral cortex of rat embryos on embryonic day 14.5, and cultured on surface treated PHBHHx films. The morphology of NSCs attached on the film was visualized under SEM, and the survival and differentiation of NSCs were observed through immunocytochemical staining. Compared with the untreated PHBHHx films, the water contact angle of NaOH or lipase treated PHBHHx films decreased dramatically, and the number of NSCs attached significantly increased. NSCs survived well on treated PHBHHx films and differentiated into neurons and glial cells. The amelioration of hydrophilic property of PHBHHx film improved its biocompatibility with NSCs. PHBHHx can serve as a novel CNS tissue engineering biomaterial applied for NSCs transplantation, brain repairing and regeneration.