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3,446 results on '"Zhang Junhua"'

111. Depressive Symptoms of Chinese Rural-to-Urban Migrant Children: A Systematic Review and Meta-Analysis

Author

Yan, Lixia, Wang, Siyuan, Yuan, Yang, Zhang, Yu, and Zhang, Junhua

Abstract

There are many contradictions in previous studies of the status of depressive symptoms among Chinese migrant children, the number of which in the compulsory education stage is about 13.9 million. This systematic review and meta-analysis were designed to compare depressive symptoms among migrant children and their urban children. Around 2,710 papers were retrieved from PubMed, OVID, the Web of Knowledge, CNKI, Wan Fang, Chongqing VIP, and Chinese Social Sciences Citation Index on January 27, 2020. Thirty-Two studies met study criteria with 14,906 migrant children and 10,792 urban children. Migrant children scored significantly higher for depressive symptoms score (SMD = 0.307, 95% CI [0.222, 0.393]). Region significantly influenced the difference of depressive symptoms between migrant children and urban children. Large effect sizes came from studies using scales that focus on depressive mood while studies using scales that focus on depressive behavioural symptoms had small effect sizes. Future research should focus on treatments to decrease depressive mood of migrant children. Future studies can add information about the length of their current stay in the urban location to improve the quality of study. PROSPERO registry: Systematic review registration no. CRD42018090676.

Published
2022
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121. Randomness expansion secured by quantum contextuality

Author

Um, Mark, Zhao, Qi, Zhang, Junhua, Wang, Pengfei, Wang, Ye, Qiao, Mu, Zhou, Hongyi, Ma, Xiongfeng, and Kim, Kihwan

Subjects
Quantum Physics, Physics - Atomic Physics, Physics - Data Analysis, Statistics and Probability
Abstract

The output randomness from a random number generator can be certified by observing the violation of quantum contextuality inequalities based on the Kochen-Specker theorem. Contextuality can be tested in a single quantum system, which significantly simplifies the experimental requirements to observe the violation comparing to the ones based on nonlocality tests. However, it is not yet resolved how to ensure compatibilities for sequential measurements that is required in contextuality tests. Here, we employ a modified Klyachko-Can-Binicio\u{g}lu-Shumovsky contextuality inequality, which can ease the strict compatibility requirement on measurements. On a trapped single \Ba ion system, we experimentally demonstrate violation of the contextuality inequality and realize self-testing quantum random number expansion by closing detection loopholes. We perform $1.29 \times 10^8$ trials of experiments and extract the randomness of $8.06 \times 10^5$ bits with a speed of 270 bits s$^{-1}$. Our demonstration paves the way for the practical high-speed spot-checking quantum random number expansion and other secure information processing applications., Comment: Main text: 12 pages, 5 figures, Supplementary Materials: 5 pages

Published
2019
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124. Reversible Crosslinked Polymer Binder for Recyclable Lithium Sulfur Batteries with High Performance

Author

Liu, Zhimeng, He, Xin, Fang, Chen, Camacho‐Forero, Luis E, Zhao, Yangzhi, Fu, Yanbao, Feng, Jun, Kostecki, Robert, Balbuena, Perla B, Zhang, Junhua, Lei, Jingxin, and Liu, Gao

Subjects
Engineering, Materials Engineering, Chemical Sciences, Physical Chemistry, Affordable and Clean Energy, binder, high sulfur loading, recyclable Li-S batteries, Physical Sciences, Materials, Chemical sciences, Physical sciences
Abstract

Owing to the negative impact of the extensive utilization of batteries on the environment, sustainability of the cells needs to be included in the systemic research of batteries. Herein, a dissolvable ionic crosslinked polymer (DICP) is exploited as a binder for lithium–sulfur batteries by crosslinking the polyacrylic acid and polyethyleneimine through carboxy-amino ionic interaction. This interaction is pH-controlled, and therefore, the crosslinked binder network can be readily dissociated under basic conditions, providing a facile strategy enabling valuable components recycled through a convenient washing method. The sulfur cathode prepared using the recycled carbon–sulfur composite can deliver comparable capacity as that of fresh electrode. In addition, evidence from cell performance and characterizations, such as in situ X-ray absorption spectroscopy, in situ UV–visible spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculation, confirms that DICP is a more effective binder than its commercial counterpart on suppressing polysulfide dissolution in the electrolyte. Exploiting reversible crosslinked polymer binder for recyclable Li–S batteries with ameliorated electrochemical performance, this study illuminates sustainable development for large-scale energy storage systems.

Published
2020

125. A minimal common outcome measure set for COVID-19 clinical research

Author

infection, WHO Working Group on the Clinical Characterisation and Management of COVID-19, Marshall, John C, Murthy, Srinivas, Diaz, Janet, Adhikari, NK, Angus, Derek C, Arabi, Yaseen M, Baillie, Kenneth, Bauer, Michael, Berry, Scott, Blackwood, Bronagh, Bonten, Marc, Bozza, Fernando, Brunkhorst, Frank, Cheng, Allen, Clarke, Mike, Dat, Vu Quoc, de Jong, Menno, Denholm, Justin, Derde, Lennie, Dunning, Jake, Feng, Xiaobin, Fletcher, Tom, Foster, Nadine, Fowler, Rob, Gobat, Nina, Gomersall, Charles, Gordon, Anthony, Glueck, Thomas, Harhay, Michael, Hodgson, Carol, Horby, Peter, Kim, YaeJean, Kojan, Richard, Kumar, Bharath, Laffey, John, Malvey, Denis, Martin-Loeches, Ignacio, McArthur, Colin, McAuley, Danny, McBride, Stephen, McGuinness, Shay, Merson, Laura, Morpeth, Susan, Needham, Dale, Netea, Mihai, Oh, Myoung-Don, Phyu, Sabai, Piva, Simone, Qiu, Ruijin, Salisu-Kabara, Halima, Shi, Lei, Shimizu, Naoki, Sinclair, Jorge, Tong, Steven, Turgeon, Alexis, Uyeki, Tim, van de Veerdonk, Frank, Webb, Steve, Williamson, Paula, Wolf, Timo, and Zhang, Junhua

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Rare Diseases, Infectious Diseases, Infection, Good Health and Well Being, Betacoronavirus, COVID-19, Clinical Trials as Topic, Coronavirus Infections, Humans, Outcome Assessment, Health Care, Pandemics, Patient Outcome Assessment, Pneumonia, Viral, SARS-CoV-2, Survival Analysis, Treatment Outcome, Viral Load, WHO Working Group on the Clinical Characterisation and Management of COVID-19 infection, Medical Microbiology, Public Health and Health Services, Microbiology, Clinical sciences, Medical microbiology, Epidemiology
Abstract

Clinical research is necessary for an effective response to an emerging infectious disease outbreak. However, research efforts are often hastily organised and done using various research tools, with the result that pooling data across studies is challenging. In response to the needs of the rapidly evolving COVID-19 outbreak, the Clinical Characterisation and Management Working Group of the WHO Research and Development Blueprint programme, the International Forum for Acute Care Trialists, and the International Severe Acute Respiratory and Emerging Infections Consortium have developed a minimum set of common outcome measures for studies of COVID-19. This set includes three elements: a measure of viral burden (quantitative PCR or cycle threshold), a measure of patient survival (mortality at hospital discharge or at 60 days), and a measure of patient progression through the health-care system by use of the WHO Clinical Progression Scale, which reflects patient trajectory and resource use over the course of clinical illness. We urge investigators to include these key data elements in ongoing and future studies to expedite the pooling of data during this immediate threat, and to hone a tool for future needs.

Published
2020

136. A Comprehensive Evaluation of China's Digital Economy: A Comparative Study with the U.K. and the U.S.

Author

Zhang, Junhua, Appolloni, Andrea, Series Editor, Caracciolo, Francesco, Series Editor, Ding, Zhuoqi, Series Editor, Gogas, Periklis, Series Editor, Huang, Gordon, Series Editor, Nartea, Gilbert, Series Editor, Ngo, Thanh, Series Editor, Striełkowski, Wadim, Series Editor, Balli, Faruk, editor, Nee, Au Yong Hui, editor, and Qalati, Sikandar Ali, editor

Published
2022
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143. Frequency stabilization of a 650 nm laser to I$_{2}$ spectrum for trapped $^{138}$Ba$^{+}$ ions

Author

Xie, Tian, Jin, Naijun, Wang, Ye, Zhang, Junhua, Um, Mark, Wang, Pengfei, and Kim, Kihwan

Subjects
Physics - Atomic Physics
Abstract

The optical manipulation of Ba$^{+}$ ions is mainly performed by a 493 nm laser for the S$_{1/2}$-P$_{1/2}$ transition and a 650 nm laser for the P$_{1/2}$-D$_{3/2}$ transition. Since the branching ratio between the 493 nm and 650 nm transitions of a single Ba$^{+}$ ion is comparable, stabilization systems of both lasers are equally important for Doppler cooling, sub-Doppler cooling, optical pumping and state detection. The stabilization system of a 493 nm laser to an absolute Te$_2$ reference has been well established. However, the stabilization of a 650 nm laser has not been presented before. Here we report twenty spectral lines of I$_{2}$ in the range of 0.9 GHz above the resonance of the P$_{1/2}$-D$_{3/2}$ transition. We stabilize the 650 nm laser through the optical cavity to the lowest one among these lines, which is about 350 MHz apart, as the absolute frequency reference. Furthermore, we measure the frequency differences between these iodine lines and the Ba$^+$ resonance through fluorescence excitation spectrum with well-resolved dark states, which is in agreement with the theoretical expectation. The presented stabilization scheme enables us to perform precise experiments with Ba$^{+}$ ions., Comment: 5 pages, 6 figures, 1 table

Published
2018
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