Energy Efficient Air-to-Ground Communication Networks with Reconfigurable Intelligent Surface

Yuanyuan Yao,Ke Lv,Nan Ma,Xinwei Yue,Xiaoqi Qin,Xiang Yun 한국통신학회 2022 Journal of communications and networks Vol.24 No.5

Reconfigurable intelligent surface (RIS) assisted air- to-ground wireless powered communication networks (WPCNs) are constructed to promote the energy efficiency of the system, in which unmanned aerial vehicles (UAV) reflects energy towards the energy-constrained hybrid access points (HAP) through RIS. Subsequently, HAP uses the collected energy to communicate with users in blind areas through the RIS-UAV. By optimizing parameters such as charging time ratio, transmit power and phase shifts matrix, the energy efficiency for single and multi- user scenarios are maximized, respectively. The energy efficiency is modeled as a non-convex quadratic programming problem with inequality constraints in the single-user scenario. Then the problem is converted into an equivalent convex problem by using the Taylor expansion and convex approximation method. A joint optimization algorithm of power and phase shifts is proposed to obtain a feasible solution. The energy efficiency is modeled as a fractional programming problem with non-convex inequality constraints in the multi-user scenario, and the feasible solution is obtained by proposing an alternating algorithm. Finally, both two scenarios are compared with the system of traditional amplify- and-forward (AF) relay, respectively. Finally, the simulation results show that the proposed algorithms can provide up with 150% and 160% improvement of the energy efficiency in the single and multi-user scenarios, respectively, compared to the traditional AF relay.

School Consolidation: Whither China’s Rural Education?

Hong Mei,Quanbao Jiang,Yuanyuan Xiang,Xiaoping Song 한국사회복지학회 2015 Asian Social Work and Policy Review Vol.9 No.2

The School Consolidation Policy in the 1990s significantly impacted Chinese rural compulsory education and Chinese rural communities. Although this policy has been involved in many negative news reports, there is a lack of scientific research on it. To address the research gap, this paper first delineates the evolution of this policy, which was formed to balance the disparity between urban and rural education, accelerated by rural financial reformation and aborted due to various emerging problems. It then discusses the educational problems caused by the policy including misallocated resources, poor quality, rising costs, student safety issues, high dropout rate, and lost rural culture heritage. Through the analyses, this paper provides a clear picture of the development of Chinese rural education, and offers implications for improving educational policy, promoting educational quality, and securing educational rights of students in rural China.

Maternal nutrition altered embryonic MYOD1, MYF5, and MYF6 gene expression in genetically fat and lean lines of chickens

Li Feng,Yang Chunxu,Xie Yingjie,Gao Xiang,Zhang Yuanyuan,Ning Hangyi,Liu Guangtao,Chen Zhihui,Shan Anshan 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.8

Objective: The objectives of this study were to evaluate the effects of daily feed intake during the laying period on embryonic myogenic differentiation 1 (MYOD1), myogenic factor 5 (MYF5), and myogenic factor 6 (MYF6) gene expression in genetically fat and lean lines of chickens. Methods: An experiment in a 2×2 factorial design was conducted with two dietary intake levels (100% and 75% of nutrition recommendation) and two broiler chicken lines (fat and lean). Two lines of hens (n = 384 for each line) at 23th week of age were randomly divided into 4 treatments with 12 replicates of 16 birds. The experiment started at 27th week of age (5% egg rate) and ended at 54th week of age. Hatched eggs from the medium laying period were collected. Real time polymerase chain reaction analysis was used to analyse the MYOD1, MYF5, and MYF6 mRNA levels of E7, E9, E11, E13, and E15 body tissues and E17, E19, and E21 chest and thigh muscle samples. Results: The results indicated that there were significant effects of line, dietary intake, and interactions between them on MYOD1, MYF5, and MYF6 gene mRNA expression levels in embryonic tissues. Low daily feed intake did not change the expression trend of MYOD1 mRNA in either line, but changed the peak values, especially in lean line. Low daily feed intake altered the trend in MYF5 mRNA expression level in both lines and apparently delayed its onset. There was no apparent effect of low daily feed intake on the trends of MYF6 mRNA expression levels in either line, but it significantly changed the values on many embryonic days. Conclusion: Maternal nutrient restriction affects myogenesis and is manifested in the expression of embryonic MYOD1, MYF5, and MYF6 genes. Long term selection for fat deposition in broiler chickens changes the pattern and intensity of myogenesis. Objective: The objectives of this study were to evaluate the effects of daily feed intake during the laying period on embryonic myogenic differentiation 1 (<i>MYOD1</i>), myogenic factor 5 (<i>MYF5</i>), and myogenic factor 6 (<i>MYF6</i>) gene expression in genetically fat and lean lines of chickens.Methods: An experiment in a 2×2 factorial design was conducted with two dietary intake levels (100% and 75% of nutrition recommendation) and two broiler chicken lines (fat and lean). Two lines of hens (n = 384 for each line) at 23th week of age were randomly divided into 4 treatments with 12 replicates of 16 birds. The experiment started at 27th week of age (5% egg rate) and ended at 54th week of age. Hatched eggs from the medium laying period were collected. Real time polymerase chain reaction analysis was used to analyse the <i>MYOD1</i>, <i>MYF5</i>, and <i>MYF6</i> mRNA levels of E7, E9, E11, E13, and E15 body tissues and E17, E19, and E21 chest and thigh muscle samples.Results: The results indicated that there were significant effects of line, dietary intake, and interactions between them on <i>MYOD1</i>, <i>MYF5</i>, and <i>MYF6</i> gene mRNA expression levels in embryonic tissues. Low daily feed intake did not change the expression trend of <i>MYOD1</i> mRNA in either line, but changed the peak values, especially in lean line. Low daily feed intake altered the trend in <i>MYF5</i> mRNA expression level in both lines and apparently delayed its onset. There was no apparent effect of low daily feed intake on the trends of <i>MYF6</i> mRNA expression levels in either line, but it significantly changed the values on many embryonic days.Conclusion: Maternal nutrient restriction affects myogenesis and is manifested in the expression of embryonic <i>MYOD1</i>, <i>MYF5</i>, and <i>MYF6</i> genes. Long term selection for fat deposition in broiler chickens changes the pattern and intensity of myogenesis.

Effects of three drying methods on polyphenol composition and antioxidant activities of Litchi chinensis Sonn.

Si Tan,Jianmin Tang,Wenjing Shi,Zhuwei Wang,Yuanyuan Xiang,Tingwei Deng,Xiaoxu Gao,Wenfeng Li,Shengyou Shi 한국식품과학회 2020 Food Science and Biotechnology Vol.29 No.3

The aim of this study was to investigate the effects of three different drying methods, freeze drying (FD), vacuum drying (VD) and oven drying (OD) on phenolic contents and antioxidant activities of litchi fruits. 20 polyphenols were exactly identified in the litchi fruits by UPLC-QqQ/MS. Significant losses were observed in the contents of total polyphenols and antioxidant activities in the dried litchi when compared with the fresh litchi. Principle component analysis indicated that there was significant difference of phenolic component between the use of thermal drying (VD and OD) and FD. Our results suggest that FD is the optimum drying method for litchi fruits considering the content of total polyphenols and antioxidant activities.

EphB1 and Ephrin-B, New Potential Biomarkers for Squamous Cell/adenosquamous Carcinomas and Adenocarcinomas of the Gallbladder

Yuan, Yuan,Yang, Zhu-Lin,Miao, Xiong-Ying,Liu, Zi-Ru,Li, Dai-Qiang,Zou, Qiong,Li, Jing-He,Liang, Lu-Feng,Zeng, Gui-Xiang,Chen, Sen-Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.3

Squamous cell/adenosquamous carcinoma (SC/ASC) of the gallbladder are rare tumors and there are few clinical reports in the literature. Herein we report our clinical experience with 46 patients with SC/ASC and 80 with adenocarcinoma (AC). Expression of EphB1 and Ephrin-B in each tumor was determined using immunohistochemical methods for determination of correlations with prognosis. There was no difference in EphB1 and Ephrin-B expression between SC/ASC and AC tumors (P>0.05), but greater expression in those less than 3 cm in diameter, stage I or II (TNM stage), with no lymph node metastases, with no local invasion and treated with radical resection was apparent. Expression of EphB1 (P<0.05) and Ephrin-B (P<0.01) was higher in well differentiated than in poorly differentiated AC tumors. Kaplan-Meier survival analysis indicated that degree of differentiation, tumor diameter, lymph node metastases, local invasion, surgical approach and expression rate of EphB1 and Ephrin-B were closely related to the survival of SC/ASC (P<0.05) and AC patients (P<0.01). Patients with tumors that positive expressed EphB1 and Ephrin-B, whether it is SC/ASC ($P_{SC/ASC}$ =0.000) or AC ($P_{AC}$ =0.000 or $P_{AC}$ =0.002) had longer survival than those negative expression. Cox multivariate analysis indicated a negative correlation between expression of EphB1 or Ephrin-B and overall survival. Hence, EphB1 and Ephrin-B could be regarded as independent good prognostic factorsand important biological markers for SC/ASC and AC of gallbladder.