Pt, Ag and Au Nanoparticles on hollow carbon spheres as cathode ORR

Yuhan Jiang,Linlin Guan,Yangjing Jiao,Chunxin Yu,Fang Zhao,Xiaowei Zhou,Zhu Liu 대한금속·재료학회 2024 ELECTRONIC MATERIALS LETTERS Vol.20 No.2

Hollow carbon spheres (HCS) have been employed as supporting materials for Pt, Ag, and Au nanoparticles (NPs) in theoxygen reduction reaction (ORR). The NPs Pt, Ag, and Au have been hydrothermally coated on HCS uniformly. The diameterof the Pt, Ag and Au NPs ranges between 11 and 32 nm, with the loading of 4.58, 4.73, and 4.07 wt.%, respectively. Itis found that Pt, Ag, and Au/HCS exhibit stable catalytic activity after 5000 CV scanning and follow a four-electron routein the ORR. Among them, Tafel plots show that Ag/HCS has the fastest kinetic rates and Pt/HCS has the largest eff ectiveactive area from CV curve. Hence HCS provides a stable supportive material for Pt, Ag, Au nanoparticle catalysts in theORR due to its nanopores structure and large surface area.

Hand-eye Calibration of Dual Mechanical Arms of Explosive Ordnance Disposal Robot

Jianfeng Jiang,Xiao Luo,Qingsheng Luo,Lijun Qiao,Yuhan Chen 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.7

The explosive ordnance disposal (EOD) robot works in a special environment, which requires dual robotic arms to work together for removing the bomb. Therefore, the coordinate calibration accuracy is the prerequisite for realizing the coordinated movement and visual positioning of the dual robotic arms. A basic problem encountered in the collaborative work of the dual robotic arms system is to determine the homogeneous transformation matrix of the frame, including: hand-eye, base-base, and gripper-camera. We formulate the hand-eye calibration problem of the dual robotic arm as the matrix equation AXB = YCZD. 1) An improved closed solution for singlerobotic arm hand-eye calibration is proposed. This closed solution of the single-robotic arm is used to quickly obtain the initial estimate of the iterative method to improve the efficiency and accuracy of the iteration. 2) The iterative solution of dual robotic arms hand-eye calibration based on the rotation vector is proposed. 3) In addition, a motion trajectory plan of the mechanical gripper is proposed to guide the operator to select the appropriate robot posture during the calibration process. In order to show the feasibility and superiority of the proposed method, a real EOD robot experiment is carried out. The comparison results from experiments show that the proposed simultaneous calibration method has higher accuracy and efficiency.

Improved Genetic Algorithm based 3-D deployment of UAVs

Xiting Wen,Yuhan Ruan,Yongzhao Li,Hongxing Xia,Rui Zhang,Chao Wang,Wei Liu,Xiaoyu Jiang 한국통신학회 2022 Journal of communications and networks Vol.24 No.2

Unmanned aerial vehicles (UAVs) are widely usedas aerial base stations (BSs) to provide flexible connectivity andcoverage for ground users in various scenarios such as disasterrelief, traffic offloading, and so on. Especially, UAV deployment isan important issue that directly affects the coverage performanceof the UAV network. In this paper, we propose a novel heuristic algorithmbased three-dimensional (3-D) UAV deployment schemewhile guaranteeing the connectivity of the UAV network in bothstatic and dynamic user scenarios. For the static user scenario, weaim to deploy the minimum number of UAVs to provide coveragefor the users from the perspective of deployment cost. To reducethe deployment complexity, we decouple the 3-D UAV deploymentproblem from the vertical and horizontal dimensions. Specifically,we firstly determine the optimal vertical height of UAVs based onthe air-to-ground (A2G) model. Then, to alleviate the prematureconvergence of standard genetic algorithm (SGA), we designan improved genetic algorithm (IGA) to obtain the optimalhorizontal locations of UAVs. On this basis, when the users moveor increase, i.e., the dynamic user scenario, the already deployedUAVs cannot provide effective coverage. For this scenario, wepropose a UAV redeployment scheme to maximize the numberof covered users without increasing the number of UAVs. Tofurther reduce the cost of redeployment, we firstly modify theproposed IGA to obtain a feasible set of two-dimensional (2-D)redeployed locations of the UAVs. Then, we design a backtrackingalgorithm (BA) based UAV movement strategy to minimize thetotal flying distance of the UAVs. The simulation results showthat the effectiveness and convergence of our proposed schemes.

Protective effect of hepatocyte-enriched lncRNA-Mir122hg by promoting hepatocyte proliferation in acute liver injury

Yu Zhenjun,Li Yuhan,Shao Shuai,Guo Beichen,Zhang Mengxia,Zheng Lina,Zhang Kun,Zhou Feng,Zhang Li,Chen Chiyi,Jiang Wentao,Hong Wei,Han Tao 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Some long noncoding RNAs (lncRNAs), which harbor microRNAs in their gene sequence and are also known as microRNA host gene derived lncRNAs (lnc-MIRHGs), play a dominant role alongside miRNAs, or both perform biological functions synergistically or independently. However, only a small number of lnc-MIRHGs have been identified. Here, multiple liver injury datasets were analyzed to screen and identify the target lncRNA Mir122hg. Mir122hg was mainly enriched in liver tissues with human-mouse homology. In both CCl4-induced acute liver injury and Dgal/LPS-induced fulminant liver failure in mice, Mir122hg was sharply downregulated at the early stage, while a subsequent significant increase was only found in the CCl4 group with liver recovery. Overexpression and silencing assays confirmed that Mir122hg played a protective role in acute injury by promoting hepatocyte proliferation in vivo and in vitro. Consistent with the results of gene enrichment analysis, Mir122hg binding to C/EBPα affected its transcriptional repression, promoted gene transcription of downstream chemokines, Cxcl2, Cxcl3, and Cxcl5, and exerted pro-proliferative effects on hepatocytes through activation of the AKT/GSK-3β/p27 signaling pathway by CXC/CXCR2 complexes. This study identifies a novel lncRNA with protective effects in acute liver injury and demonstrates that the binding of Mir122hg-C/EBPα promotes hepatocyte proliferation via upregulation of CXC chemokine and activation of AKT signaling.

Effect of Multiple Freeze-Thaw Cycles on Lipid Degradation and Lipid Oxidation of Grass Carp Surimi Containing Different Amounts of Pork Back Fat

Xiaolan Shang,Juan Du,Yuhan Zhao,Jiajia Tian,Shuhui Jiang 한국축산식품학회 2021 한국축산식품학회지 Vol.41 No.6

Fresh grass carp was used to produce surimi samples that were supplemented with 50 g/kg, 100 g/kg, or 150 g/kg pork back fat. The lipid composition, lipase activity, lipid oxidation index, and lipoxygenase activity of samples subjected to repeated freezethaw process were determined to assess the effects of the added fat on lipolysis and lipid oxidation of grass carp surimi. Freeze-thaw treatment increased free fatty acid content, mainly due to the decomposition of phospholipids and some neutral lipids by lipase. With repeated freeze-thaw treatment, the levels of free fatty acids and phospholipids were correlated with the lipid oxidation indexes and lipoxygenase activity, indicating that lipid degradation can promote lipid oxidation. In the same freeze-thaw cycle, surimi products with high fat content are more vulnerable to oxidative damage, neutral lipids are the main source of free fatty acids in the early stage of freeze-thaw, and phospholipids are the main source of free fatty acids in the late stage.

중국 공공조직 구성원의 공공봉사동기가 조직몰입에 미치는 영향: 잡 크래프팅과 직무배태성의 연속다중매개효과

신광철 ( Shen Guangzhe ),강재열 ( Kang Jaeyeol ),강유한 ( Jiang Yuhan ),한재용 ( Han Jaeyoung ) 한국비교경제학회 2023 비교경제연구 Vol.30 No.2

조직몰입, 잡 크래프팅, 직무배태성의 연구가 중요한 개념으로 주목받고 있지만 공공부문 맥락에서는 경험적 연구가 거의 이루어지지 않았다. 이에 본 연구는 공공조직에서 공공봉사동기가 직무배태성에 미치는 영향, 그 관계에서 조직몰입, 잡 크래프팅의 연속다중매개 효과를 검증하였다. 연구결과 공공봉사동기의 하위요인인 정책결정에 대한 호감도, 공익몰입, 동정심, 자기희생은 모두 조직몰입에 유의미한 정(+)의 영향을 미친 것으로 나타났고, 잡 크래프팅의 매개효과 검증에서 공익몰입, 동정심, 자기희생과 조직몰입 간의 관계에서 잡 크래프팅의 매개효과는 유의미하지만 정책결정에 대한 호감도와 조직몰입 간의 관계에서 잡 크래프팅의 매개효과는 유의미하지 않는 것으로 나타났다. 직무배태성의 매개효과 검증에서 정책결정에 대한 호감도, 공익몰입, 동정심, 자기희생과 조직몰입 간의 관계에서 직무배태성의 매개효과는 전부 유의미하였고, 잡 크래프팅과 직무배태성의 연속다중매개역할 검증에서 정책결정에 대한 호감도와 조직몰입 간의 관계에서만 잡 크래프팅과 직무배태성의 연속다중매개효과는 유의미하지 않는 걸로 나타났다. 이러한 연구결과를 바탕으로 본 연구의 시사점, 한계 및 향후 과제를 제시하였다. Faced with the increasingly growing and complex public service needs and requirements of the people, the Chinese government is recruiting and cultivating talents with high-level public service motivation as members of public organizations. Members of Chinese public organizations should also become innovative public service providers, by redesigning their positions that are suitable for them, improving their level of fertility in the job environment, enhancing their trust and attachment to stagnant organizations, and ultimately taking on the important responsibility of promoting the development of public services and serving the people. Therefore, the purpose of this study is to reveal the mediating and continuous multiple mediating effects of job crafting and job embeddedness from the impact of public service motivation of Chinese public organization members on organizational commitment. In order to conduct empirical research, an online questionnaire survey was conducted among members of Chinese public organizations, with a total of 276 questionnaire materials used as samples in the final analysis. As a result of the study, it was found that the sub-factors of public service motivation, such as attraction to policy making, serve the public interest, compassion, and self-sacrifice, all had a significant positive(+) impact on organizational commitment. In testing the mediating effect of job crafting, it was found that the mediating effect of job crafting was significant in the relationship between serve the public interest, compassion, self-sacrifice, and organizational commitment, but the mediating effect of job crafting was not significant in the relationship between attraction to policy making and organizational commitment. In testing the mediating effect of job embeddedness, the mediating effects of job embeddedness were all significant in the relationships between attraction to policy making, serve the public interest, compassion, self-sacrifice, and organizational commitment. In testing the continuous multiple mediating effects of job crafting and job embeddedness, the continuous multiple mediating effect of job crafting and job embeddedness was found to be insignificant only in the relationship between attraction to policy making and organizational commitment. Based on these research results, implications, limitations, and future tasks of this study were presented.

Astaxanthin supplementation enriches productive performance, physiological and immunological responses in laying hens

Zhu Yuanzhao,Yin Long,Ge Jinshan,Wu Xuezhuang,Peng Yuhan,Zhang Tao,Jiang Meihong 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.3

Objective: Astaxanthin is a natural super antioxidant. The present study was carried out to investigate the effect of astaxanthin rich Phaffia rhodozyma (PR) supplementation in diets on laying production performance, egg quality, antioxidant defenses and immune defenses in laying hens. Methods: A total of five hundred and twelve 60-week-old Lohmann Brown laying hens (2,243±12 g) were randomly assigned to four groups, each including 4 replicates with 32 birds per replicate. Astaxanthin rich PR was added to corn-soybean meal diets to produce experimental diets containing 0 (Control), 800 mg/kg, 1,200 mg/kg, and 1,600 mg/kg PR, respectively. The astaxanthin content in the diet was 0.96 mg/kg, 1.44 mg/kg and 1.92 mg/kg respectively. Results: Results showed that dietary PR supplementation tended to increase daily feed intake (p = 0.0512). There was no effect of astaxanthin rich PR on Haugh units, albumen height, egg shape index, eggshell strength, and eggshell thickness at weeks 6 (p>0.05). However, egg yolk color was significantly improved (p<0.05). In addition, astaxanthin rich PR supplementation significantly increased serum glutathione peroxidase and superoxide dismutase activity (p<0.05), increased serum immunoglobulin G content (p<0.05), and reduced malondialdehyde content (p<0.05) in laying hens. Conclusion: In conclusion, astaxanthin rich PR can improve the color of egg yolk, enhance the antioxidant defenses, and regulate the immune function. Objective: Astaxanthin is a natural super antioxidant. The present study was carried out to investigate the effect of astaxanthin rich <i>Phaffia rhodozyma</i> (PR) supplementation in diets on laying production performance, egg quality, antioxidant defenses and immune defenses in laying hens.Methods: A total of five hundred and twelve 60-week-old Lohmann Brown laying hens (2,243±12 g) were randomly assigned to four groups, each including 4 replicates with 32 birds per replicate. Astaxanthin rich PR was added to corn-soybean meal diets to produce experimental diets containing 0 (Control), 800 mg/kg, 1,200 mg/kg, and 1,600 mg/kg PR, respectively. The astaxanthin content in the diet was 0.96 mg/kg, 1.44 mg/kg and 1.92 mg/kg respectively.Results: Results showed that dietary PR supplementation tended to increase daily feed intake (p = 0.0512). There was no effect of astaxanthin rich PR on Haugh units, albumen height, egg shape index, eggshell strength, and eggshell thickness at weeks 6 (p>0.05). However, egg yolk color was significantly improved (p<0.05). In addition, astaxanthin rich PR supplementation significantly increased serum glutathione peroxidase and superoxide dismutase activity (p<0.05), increased serum immunoglobulin G content (p<0.05), and reduced malondialdehyde content (p<0.05) in laying hens.Conclusion: In conclusion, astaxanthin rich PR can improve the color of egg yolk, enhance the antioxidant defenses, and regulate the immune function.