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Lithium titanate (Li4Ti5O12, LTO) is an important material to be used as an anode for LIBs (Li+ ion battery). LTO is a zero-strain material (i.e., no structural change occurs during Li insertion/extraction). Although LTO is a very safe material that can be used as an anode material in high and low temperature environment, its rate capability is compromised by its low electronic conductivity and poor Li+ diffusion coefficient. In the recent years, considerable research around the world has focused on improving LTO rate performance. Efforts to achieve better electrical conduction between LTO particles have included LTO particle size control, conductive-material surface coatings, and alien ion doping. However, in this study electrochemical properties were improved by changing the morphology of LTO. Based on traditional electrospinning technology, LTO fibers with a hollow structure were produced using a nested coaxial nozzle modified from the conventional spinning nozzle and coaxial cospinning with two different solutions. A comparison of this results with those of solid LTO prepared by traditional electrospinning technology demonstrates that hollow LTO is characterized by uniform particle size and no agglomeration, along with an obvious hollow structure, clear crystal lattice stripes, and good crystallization property. The specific surface of this hollow LTO is 1.3 times than its solid counterpart. This morphological change greatly improves the electrochemical performance of the material. Although the discharge specific capacities of both the solid and hollow LTO are close to the theoretical value for small ratios, the hollow LTO is superior to its solid counterpart at 20C. The discharge specific capacity of the hollow LTO can reach 130 mA·h·g-1 at 20C, and after 200 cycles, its capacity retention ratio remains at 98%, which suggests good stability. Cyclic voltammetry and AC impedance curves also show that the hollow structure reduces the degree of polarization and the electrochemical reaction impedance of LTO, which makes LTO more conducive to electrochemical reaction.

Transit properties increasingly provide multiple modes of transit service, creating a need for intermodal transit performance indicators. Transit performance indicators currently in use do not have the capability of comparing the performance of different modes. In addition, most indicators in current use incorporate only operating costs, while for many transit modes capital costs constitute a significant proportion of total costs. The research conducted reviewed the use of performance indicators by urban transit properties in California, and found that the most common measures in use are operating cost per revenue vehicle hour, operating cost per passenger boarding, farebox revenue per operating cost, passenger boardings per revenue vehicle mile, and passenger boardings per revenue vehicle hour. Three critical limitations to commonly used performance indicators are identified, and new intermodal performance indicators are proposed which overcome the limitations of current single mode indicators by incorporating mechanisms for comparisons of one mode to another, for rating the performance of systems which include multiple nodes, and by incorporating both capital and operating costs. The proposed comprehensive transit performance indicators are total cost per revenue capacity kilometer, total cost per revenue capacity hour, total cost per passenger kilometer, passenger revenue per total cost, passenger kilometers per revenue capacity kilometer, and passenger kilometer per revenue capacity hour.

The path planning problem of mobile robot in unknown dynamic environment (UDE) is discussed in this article by building a continuous dynamic simulation environment. To achieve a collision‐free path in UDE, the reinforcement learning theory with deep Q‐network (DQN) is applied for the mobile robot to learn optimal decisions. A reward function is designed with weight to balance the obstacle avoidance and the approach to the goal. Moreover, it is found that the relative motion between moving obstacles and robots may cause abnormal rewards and further lead to a collision between robot and obstacle. To address this problem, two reward thresholds are set to modify the abnormal rewards, and the experiments shows that the robot can avoid all obstacles and reach the goal successfully. Finally, double DQN (DDQN) and dueling DQN are applied in this article. This article compares the results of reward‐modified DQN (RMDQN), reward‐modified DDQN (RMDDQN), dueling RMDQN, and dueling RMDDQN and concludes that the result of RMDDQN is the best. [ABSTRACT FROM AUTHOR]

Objective To investigate the fundus arteriosclerosis and its influencing factors in HIV/AIDS patients after long-term highly active antiretroviral therapy (HAART). Methods The clinical basic data and fundus examination data of 203 HIV/AIDS patients before and after HAART in the Fourth People 's Hospital of Nanning from January 2020 to June 2022 were collected to evaluate the occurrence of fundus arteriosclerosis and analyze its influencing factors. Results Of the 203 HIV/AIDS patients, 159 patients developed fundus arteriosclerosis, with an incidence of 78.33%, including 33 patients with grade (20.75%), 87 patients with grade (54.72%), 28 patients with grade (17.61%), and 11 patients (6.92%) with Grade . Before HAART, there was no significant difference in CD4+T lymphocyte count, CD8+T lymphocyte count, viral load, white blood cell count, platelet count, hemoglobin, serum creatinine, blood urea nitrogen, triacylglycerol, total cholesterol, fasting blood glucose, alanine aminotransferase, aspartate aminotransferase and serum total bilirubin between the atherosclerosis group and normal group (P>0.05). After 6 months of HAART, CD8+T lymphocyte count, triacylglycerol and fasting blood glucose in atherosclerosis group were significantly higher than those in normal group (P<0.05). In the stratified comparison of CD4+ and CD8+ lymphocyte counts after 6 months of HAART, the proportion of patients with CD4+ lymphocyte count (CD4+)<200 (cells/ µL) in the atherosclerosis group was significantly higher than that in the normal group; the proportion of patients with CD4+ lymphocyte count (CD4+)≥500 (cells/µL) was significantly lower than that in the normal group; the proportion of patients with CD8+ lymphocyte count CD8+≥ 800/µL was significantly higher than that in the normal group (all P<0.05). Binary logistic regression analysis showed that opportunistic infection, HIV course, CD4+ T, CD8+ T lymphocyte count after HAART and triglyceride were independent risk factors for ocular fundus atherosclerosis in HIV / AIDS patients (all P<0.05). Conclusions The incidence of ocular fundus arteriosclerosis is high in HIV/AIDS patients. More than 4 years of HIV course, combined opportunistic infection, Low CD4+T lymphocyte count after 6 months of HAART, high CD8+T lymphocyte count and high triglyceride level are independent risk factors for ocular fundus arteriosclerosis in HIV/AIDS patients. Fundus screening should be performed before and after HAART in such population, HAART program should be formulated for the risk of cardiovascular disease, and risk management of cardiovascular disease should be strengthened during treatment to improve patient outcomes. [ABSTRACT FROM AUTHOR]

To promote efficient utilization of cowpea germplasm resources and new gene discovery, a genetic linkage map containing 2984 Bin markers (142,146 SNPs) was constructed based on cowpea F2 population using re-sequencing technology. The map consisted of 11 linkage groups with a total length of 1333.48 cM and an average map spacing of 0.45 cM. The length of different linkage groups ranged from 84.63 cM to 183.15 cM, and the average plot distance ranged from 0.27 cM to 0.89 cM. A total of 15 QTLs were detected to be associated with 14 traits, including 100-grain weight, flower color, pod length, pod shape, pod shape and grain color, respectively. One major QTL region was detected for pod type, pod length, and number of branches per main stem, and multiple QTLs regions were detected for other traits. Candidate genes related to pod length, number of pods per plant, and single/double color of grains were further identified by gene annotation analysis in the interval. The results of QTL analysis in this study will lay a foundation for marker-assisted selection of important traits of cowpea, and candidate gene screening will help to further analyze the genetic mechanism of these traits and improve the level of molecular genetics research of cowpea. [ABSTRACT FROM AUTHOR]

The Five-hundred-meter Aperture Spherical radio Telescope (FAST), the largest single-dish radio telescope in the world, has implemented an innovative technology for its huge reflector, which changes the shape of the primary reflector from spherical to that of a paraboloid of 300-m aperture. Here, we explore how the current FAST sensitivity can potentially be further improved by increasing the illuminated area (i.e. the aperture of the paraboloid embedded in the spherical surface). Alternatively, the maximum zenith angle can be increased to give greater sky coverage by decreasing the illuminated aperture. Different parabolic apertures within the FAST capability are analyzed in terms of how far the spherical surface would have to move to approximate a paraboloid. The sensitivity of FAST can be improved by approximately 10 per cent if the aperture of the paraboloid is increased from 300 to 315 m. The parabolic aperture lies within the main spherical surface and does not extend beyond its edge. The maximum zenith angle can be increased to approximately 35º from |$26{_{.}^{\circ}}4$|⁠ , if we decrease the aperture of the paraboloid to 220 m. This would still give a sensitivity similar to the Arecibo 305-m radio telescope. Radial deviations between paraboloids of different apertures and the spherical surfaces of differing radii are also investigated. Maximum zenith angles corresponding to different apertures of the paraboloid are further derived. A spherical surface with a different radius can provide a reference baseline for shape-changing applied through active reflector technology to FAST-like telescopes. [ABSTRACT FROM AUTHOR]

Introduction: Gap junctions are intercellular channels formed by connexin facilitating communication between cells by allowing transfer of ions and small signaling molecules. Connexin 43 (Cx43) is the most ubiquitous connexin in human tissues. Ample evidence suggests the role of gap junction and its connexins such as connexin 43 in human cancers including gastric cancer, which has an important place in the worldwide incidence of cancer and cancer-related deaths. Due to a number of contradictory studies and insufficient detailed examination in specific cancers, such as gastric cancer, more data on the role of gap junctions and their connexins such as Cx43 involved in gastric cancer remain necessary.Material and Methods: Transmission electron microscopy, Western blotting and RT-PCR were used to show the ultrastructure damage of the gap junction in the gastric carcinoma tissue as well as the expression of Cx43 protein and mRNA, respectively.Results: Ultrastructure damage of the gap junction in gastric carcinoma tissue was shown while poorly differentiated tissue experienced greater damage. The expression of Cx43 protein and mRNA was higher in healthy gastric tissue than in carcinomatous gastric tissue (p < 0.05). There was higher expression of Cx43 protein and mRNA in high-medium differentiation than in poor differentiation (p < 0.05). Cx43 protein and mRNA expression is not statistically significant for different ages and sex (such as for > 56 and ≤ 56 years) (p > 0.05).Conclusions: Ultrastructural changes of gap junctions with abnormal Cx43 expression are associated with occurrence and development of gastric cancer, which provides a new research direction for gastric cancer pathogenesis and targeted therapy. [ABSTRACT FROM AUTHOR]

A new compound, ethyl 5‐phenyl‐2‐(p‐tolyl)‐2H‐1,2,3‐triazole‐4‐carboxylate was successfully introduced and synthesized as a novel rhodamine B derivative named REPPC, and characterized by 1H nuclear magnetic resonance (NMR), 13C NMR, and high resolution mass spectrometry (HRMS). It showed an obvious fluorescence and UV–visible light absorption enhancement towards Hg2+ ion without interference from common metal ions in N,N‐dimethylformamide–H2O (pH 7.4). The spirolactam ring moiety of rhodamine in REPPC was converted to the open‐ring form generating a 1:1 complex with the intervention of a mercury ion, verified by electrospray ionization‐mass spectroscopy testing and density functional theory calculation. REPPC was used to visualize the level of mercury ions in living HeLa cells with encouraging results. [ABSTRACT FROM AUTHOR]

Introduction: People living with HIV/AIDS (PLWHA) have a higher rate of suicide compared to the general population. Psychosocial factors closely correlate with suicidal ideation and it is essential to explain the relationships between related factors among PLWHA.Objectives: To establish a structural equation model and examine direct and indirect effects of social support, coping strategy, depression symptoms and suicidal ideation among PLWHA. Patients and methods: A total of 504 PLWHA completed a set of questionnaires in the HIV clinic of Changsha Infectious Disease Hospital between December 2015 and January 2016. Results: Among the 504 respondents, a total of 27.2% (n=137) had experienced suicidal ideation in their lifetime. The goodness of fit for the two structural equations model was highly satisfactory. Depression symptoms had a significant direct impact on suicidal ideation (β1=0.401, β2=0.422), while problem-focused coping (β=-0.067), emotion-focused coping (β=-0.081) and social support (β=-0.137) had a significant indirect effect with suicidal ideation via depression symptoms. Factors of total effects were ranked from large to small as follows: depression, social support, emotion-focused coping and problem-focused coping. Conclusion: Findings provide more understanding of direct and indirect associations between variables, suggesting that depression screening services, and the strengthening of social support and psychological care services among PLWHA can potentially prevent suicide. [ABSTRACT FROM AUTHOR]