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Objective There is increasing neuroimaging evidence that type 2 diabetes patients with retinal microvascular complications show abnormal brain functional and structural architecture and are at an increased risk of cognitive decline and dementia. However, changes in the topological properties of the functional brain connectome in diabetic retinopathy (DR) patients remain unknown. The aim of this study was to explore the topological organization of the brain connectome in DR patients using graph theory approaches. Methods Thirty-five DR patients (18 males and 17 females) and 38 healthy controls (HCs) (18 males and 20 females), matched for age, sex, and education, underwent resting-state magnetic resonance imaging scans. Graph theory analysis was performed to investigate the topological properties of brain functional connectome at both global and nodal levels. Results Both DR and HC groups showed high-efficiency small-world network in their brain functional networks. Notably, the DR group showed reduction in the clustering coefficient (P=0.0572) and local efficiency (P=0.0151). Furthermore, the DR group showed reduced nodal centralities in the default-mode network (DMN) and increased nodal centralities in the visual network (VN) (P

We report an all-fiberized chirped pulse amplification system without any bulk devices. The stretcher and compressor are chirped fiber Bragg gratings inscribed in a 6/125 μm single-mode fiber and a 30/250 μm large-mode-area fiber. The fabrication system of chirped fiber Bragg gratings was designed and built by ourselves. The width of the linear exposure spot was controlled according to the different fiber sizes to improve the fabrication quality, and the parameters of chirped fiber Bragg gratings were fine-tuned during the fabrication to achieve the overall system’s spectral matching. Two fiber circulators with the same fiber sizes as the chirped fiber Bragg gratings were employed to auxiliarily achieve the pulse stretching and compression. The dispersion accumulations provided by the stretcher and compressor are 129.8 ps and 90.8 ps. The power amplifiers were composed of the two-stage 10/130 μm fiber pre-amplifier and the 30/250 μm fiber main amplifier. The proposed chirped pulse amplification system with no spatial light is the true sense of an all-fiberized chirped pulse amplification structure and shows the main trend in development of ultrashort pulse fiber lasers.

Objective There is increasing neuroimaging evidence that type 2 diabetes patients with retinal microvascular complications show abnormal brain functional and structural architecture and are at an increased risk of cognitive decline and dementia. However, changes in the topological properties of the functional brain connectome in diabetic retinopathy (DR) patients remain unknown. The aim of this study was to explore the topological organization of the brain connectome in DR patients using graph theory approaches. Methods Thirty-five DR patients (18 males and 17 females) and 38 healthy controls (HCs) (18 males and 20 females), matched for age, sex, and education, underwent resting-state magnetic resonance imaging scans. Graph theory analysis was performed to investigate the topological properties of brain functional connectome at both global and nodal levels. Results Both DR and HC groups showed high-efficiency small-world network in their brain functional networks. Notably, the DR group showed reduction in the clustering coefficient (P=0.0572) and local efficiency (P=0.0151). Furthermore, the DR group showed reduced nodal centralities in the default-mode network (DMN) and increased nodal centralities in the visual network (VN) (P

AIM: To assess the effects of small incision lenticule extraction (SMILE) surgery on the corneal endothelium at 1d to 1mo postoperatively. METHODS: A retrospective, observational study was conducted on 47 patients (47 eyes) who received SMILE surgery. Patients were grouped according to contact lens wear condition. The corneal endothelium was examined preoperatively and at 1d, 1wk and 1mo postoperatively. The corneal endothelium was analyzed for endothelial cell density (ECD), percentage of hexagonal cells, and coefficient of variation (CV) of cell size. RESULTS: There were no significant decrease in the ECD, percentage of hexagonal cells or increase in CV at 1d, 1wk and 1mo postoperatively (P>0.05). However, there was a small increase of ECD by 2.88% in contact lens wearers (78.26±113.62 cell/mm2, P

Graphite materials are widely used in the metallurgical, chemical and defense industry due to their good thermal conductivity and chemical stability. Their chemical stability, in particular, leads to their greater application in storing and transporting the heat storage medium, Solar Salt, in solar thermal power generation. This paper adopted XRD, SEM and EDX to study the hot corrosion failure mechanisms of four kinds of graphite in molten Solar Salt which were produced with different raw materials and molding processes. The results show that the degrees of graphitization of sample 3, sample 4, sample 1, and sample 2 are respectively 85.03%, 82.80%, 80.70% and 79.92%; The higher the degree of graphitization, the better the hot corrosion resistance of the graphite to molten Solar Salt. The corrosion failure of graphite in the molten Solar Salt is mainly caused by the molten salt molecules infiltrating into the micro pores of the graphite which remain inside the graphite after cooled, causing its shrinkage, crack and deformation. There is no chemical reaction between the molten Solar Salt and the graphite, nor is there any new phase generated in the corrosion process.

Objective: To study and analyze the influence of retroperitoneal laparoscopic surgery for the body antioxidant capacity and pain stress state of patients with localized renal carcinoma. Methods: A total of 56 patients with localized renal carcinoma in our hospital from January 2014 to August 2015 who were treated with surgery were divided into two groups according to the differences of surgery, 28 cases in control group were treated with open surgery, 28 cases in observation group were treated with retroperitoneal laparoscopic surgery, then the related indexes of antioxidant capacity and pain stress state of two groups before the surgery and at first, fifth and tenth day after the surgery were compared. Results: The related indexes of antioxidant capacity and pain stress state of two groups before the surgery all had no significant differences, while the related indexes of antioxidant capacity and pain stress state of observation group at first, fifth and tenth day after the surgery were all better than those of control group, the differences were all significant. Conclusion: The influence of retroperitoneal laparoscopic surgery for the body antioxidant capacity and pain stress state of patients with localized renal carcinoma is more active, so it is more suitable for the treatment of localized renal carcinoma.

The paper deals with a single machine scheduling problem with deteriorating jobs and group technology (GT) assumption. By deteriorating jobs and group technology assumption, we mean that the group setup times and job processing times are both simple linear functions of their starting times. We show that the makespan minimization problem with release dates can be solved in polynomial time.

Solar Salt is the best hot transfer medium molten salt of solar thermal power generation.In order to study the hot corrosion behavior of four graphite is in the molten Solar Salt.The graphite immersed equipped with molten salt crucible placed in a muffle furnace,each period of time remove the sample and weight the weight gain until the sample is completely destroyed.The destruction forming of graphite is analyzed by XRD, SEM and OP.The study found that the order of hot resistant corrosion of molten Solar Salt of four graphite materials are the fine structuregraphite,isostatic graphite,9# graphite and cold pressing graphite.The principal factors can affect hot corrosion resistant of graphite is the graphitization degree. The hot corrosion resistance of the graphite can be enhanced with the increase of graphitization degree.

Scheduling research has increasingly taken the concept of deterioration into consideration. In this paper, we study a single machine group scheduling problem with deterioration effect, where the jobs are already put into groups, before any optimization. We assume that the actual processing times of jobs are increasing functions of their starting times, i.e., the job processing times are described by a function which is proportional to a linear function of time. The setup times of groups are assumed to be fixed and known. For some special cases of minimizing the makespan with ready times of the jobs, we show that the problem can be solved in polynomial time for the proposed model. For the general case, a heuristic algorithm is proposed, and the computational experiments show that the performance of the heuristic is fairly accurately in obtaining near-optimal solutions. The results imply that the average percentage error of the proposed heuristic algorithm from optimal solutions is less than 3%.

The texture feature and grain refinement effect of Al-5Ti-C alloy on pure aluminum were analyzed and its attenuation mechanism was discussed by using X-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy (OM) and other experimental methods.The results show that: Al-5Ti-C alloy is composed of Al, TiAl3 and TiC. Al-5Ti-C alloy has a good grain refining capacity for commercially pure aluminum. During the heat preservation process, due to precipitation of titanium compound in the aluminum melt, refinement effect of Al-Ti-C alloy is declined.

In order to study the effect of tantalum to the microstructure and phase composition of Co-8.8Al-9.8W-XTa (X=0,2,at%) superalloy. The Co-8.8Al-9.8W-XTa (X=0,2) supperalloy used pure element powder, according to the ratio of different atomic percentage composition to make ingredients. It is mixed by planetary ball mill, pressed into blocks after the melting shape. Vacuum induction melting process was prepared by melting, after grinding, polishing, and after a volume of 5% perchloric acid and 95% of the electrolytic etching solution prepared in ethanol corrosion observed after analysis of the microstructure and phase composition by OM and XRD analysis. It can be found that the 9.8W and 2Ta alloy were mainly composed of rich γ-Co matrix of austenite precipitation of γ phase and coherent with matrix of the L12 structure of γ′-Co3(Al,W) phase. In addition, Ta element has effect on grain refinement and the number of γ′-Co3(Al,W) phase refines grain.

Co-based high temperature alloys have been widely used in aeronautics and astronautics industry, because of its high strength at high temperature, excellent resistance of hot corrosion and oxidation. Unlike the traditional Co-based superalloys, strengthened by solution and carbide strengthening, the novel Co-Al-W superalloys are strengthened by a ternary compound with the Ll2 structure γ-Co3(Al,W). And the novel Co-Al-W superalloys showing high-temperature strength greater than those of conventional nickel-base superalloys, will become the candidates for next-generation high-temperature materials. We research alloying element Ta effect on microstructure of Co-Al-W superalloys by vacuum arc melting. Compare with the microstructure before and after adding alloying element Ta of Co-Al-W superalloy, we find that most of Ta element distributed in the γ-Co substrate phase, stabilizing and reinforcement the γ phase.

Co-Al-W supperalloy used pure element powder, according to the ratio of different atomic percentage composition to make ingredients. It is mixed by planetary ball mill, pressed into blocks after the melting shape. Vacuum arc melting process was prepared by melting, after grinding, polishing, and after a volume of 5% perchloric acid and 95% of the electrolytic etcheing solution prepared in ethanol corrosion observed after analysis of the microstructure and phase composition by XRD analysis .It can be found that Co-Al-W superalloys were mainly composed of cobalt-rich matrix of austenite precipitation of γ phase and coherent with matrix of the L12 structure of γ′-Co3(Al,W) phase. In addition, Nb have effect on grain refinement and refine grain. Rockwell hardness test and analysis, It can be found that Nb can clearly improve the Co-Al-W superalloy hardness.

Cobalt-based Stellite 6 alloy rely primarily on carbides, forming in the Co matrix and grain boundaries, for their strength and the distribution, size and shape of carbides depend on processing conditions. We have employed microstructure and corrosion behavior of Stellite 6 by combustion synthesis and vacuum induction melting with scanning electron microscopy, electron probe microscopy analysis. The results show that there are significant uniformity on microstructure and corrosion behavior of Stellite 6 by different techniques. The combustion synthesis has more advantages over conventional manufacturing process for Stellite 6.

In this paper, laser cladding was deposited Co-9Al-7.5W superalloy on 304 austenite stainless steel plate and cladding layer shape, dilution, Vickers hardness, microstructure and distribution of alloying elements were investigated. It was found that laser cladding layer has the characteristics of large dilution rate, fine microstructure, narrow heat-affected zone (HAZ), narrow alloy elements segregation, high Vickers hardness, high contents of alloying elements and low contents of Fe in the cladding layers.