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6LoWPAN中基于Mesh-under的备用缓存机制 被引量:1
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作者 刘乔寿 景晓丽 吉福生 《系统工程与电子技术》 EI CSCD 北大核心 2017年第7期1625-1632,共8页
在基于Mesh-under的IPv6低功耗无线个域网(IPv6over low-power wireless personal area networks,6LoWPAN)中,针对传输路径上中间节点重传缓存溢出导致重传数据分片丢失,造成网络性能下降等问题,提出一种基于Mesh-under的备用缓存机制... 在基于Mesh-under的IPv6低功耗无线个域网(IPv6over low-power wireless personal area networks,6LoWPAN)中,针对传输路径上中间节点重传缓存溢出导致重传数据分片丢失,造成网络性能下降等问题,提出一种基于Mesh-under的备用缓存机制。本文所提机制根据传输路径上各节点重传缓存使用情况及数据分片剩余跳数等信息,设置动态重传缓存门限,并为超过该门限的节点从其邻居节点中挑选合适的备用缓存节点,从而完成数据分片的缓存与重传过程,达到均衡使用各节点重传缓存的目的。结果表明,所提机制能够有效避免重传缓存溢出,减小网络能耗,同时进一步提高目的端重组成功率。 展开更多
关键词 IPv6低功耗无线个域网 Mesh-under 缓存门限 备用缓存
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缺氧激活前药TH-302联合舒尼替尼抑制肾细胞癌体外增殖及裸鼠成瘤能力 被引量:1
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作者 刘秀兰 裘琳 刘异 《中国医院药学杂志》 CAS 北大核心 2020年第23期2430-2434,共5页
目的:研究缺氧激活前药TH-302联合舒尼替尼抑制肾细胞癌(786-O细胞)体外增殖及裸鼠成瘤能力,深入探讨其分子机制。方法:采用四甲基偶氮唑蓝(MTT)比色法检测在缺氧条件下TH-302联合舒尼替尼对人肾癌786-O细胞增殖抑制率;建立786-O细胞裸... 目的:研究缺氧激活前药TH-302联合舒尼替尼抑制肾细胞癌(786-O细胞)体外增殖及裸鼠成瘤能力,深入探讨其分子机制。方法:采用四甲基偶氮唑蓝(MTT)比色法检测在缺氧条件下TH-302联合舒尼替尼对人肾癌786-O细胞增殖抑制率;建立786-O细胞裸鼠皮下移植瘤模型,通过免疫组化及qPCR法检测TH-302联合抑制裸鼠肿瘤生长的效果及作用机制。结果:在缺氧条件下,TH-302联合在抑制786-O细胞增殖作用中发挥协同作用;联合组可显著抑制肿瘤体积的生长,差异有统计学意义(P<0.05)。与TH-302组相比,TH-302联合舒尼替尼显著降低异种移植瘤中的缺氧区域,深入研究发现,与TH-302组相比,TH-302联合舒尼替尼组显著抑制肿瘤组织中HIF-1α,HIF-2α的表达。结论:TH-302联合舒尼替尼抑制肾癌细胞恶性增殖,减少肿瘤组织的缺氧区域,其作用机制可能与HIF-1α,HIF-2α的表达量变化有关。 展开更多
关键词 TH-302 舒尼替尼 肾癌 缺氧激活
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Hierarchical porous induced competent removal of low concentration azo dye molecules by generating a leachy crystalline structure H-MIL-53(Fe) 被引量:2
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作者 Tao Feng Jean Pierre Bavumiragira +4 位作者 Mumbi Anne Wambui Daniel Manaye Kabtamu Krisztina László Ying Wang Fengting Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第10期2717-2720,共4页
The development in technology of synthetic azo dyes,has led to excessive water resources pollution.Eve n at lower concentration they can impart the quality of water and human life.Herein,we have developed a novel synt... The development in technology of synthetic azo dyes,has led to excessive water resources pollution.Eve n at lower concentration they can impart the quality of water and human life.Herein,we have developed a novel synthesis strategy via introducing salicylic acid(SA)for the synthesis of a leachy crystalline material H-MIL-53(Fe)with hierarchical pores(HP)and exposed coordination unsaturated sites(CUS),which had higher surface area and larger pore volume than the as synthesized MIL-53(Fe).Due to these characteristics,H-MIL-53(Fe)was competent removal of orange G(OG,one of the frequently used azo dyes)with equilibrium in 300 min and the maximum adsorption capacity of 163.9 mg/g.The adsorption mechanism of OG onto H-MIL-53(Fe)was mostly based on electrostatic attraction between CUS of HMIL-53(Fe)along with HP as active species to OG diffusion and bind.By comparing H-MIL-53(Fe)with other adsorbents for OG adsorption,it is undoubtedly that H-MIL-53(Fe)can be used as a promising adsorbent for OG removal from aqueous solutions. 展开更多
关键词 H-MIL-53(Fe) Salicylic acid Leachy crystalline Adsorption Orange G removal
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PRELIMINARY COMPARISON OF SENSITIVITY TOWARD PARVO VIRUS H-1 OF HUMAN HEP ATOM A CELLS AND PARAHEPATOMA TISSUE 被引量:1
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作者 林万敏 崔衍贞 +2 位作者 俞伯根 罗祖玉 林芷英 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第3期18-23,共6页
Preliminary observations on the result of infection by parvovirus of primary cultured cells of human hepatoma and parahepatoma tissue were reported. Human hepatoma and parahepatoma tissue were obtained by the culture ... Preliminary observations on the result of infection by parvovirus of primary cultured cells of human hepatoma and parahepatoma tissue were reported. Human hepatoma and parahepatoma tissue were obtained by the culture method of tissue fragment plating. It was observed that their respective sensitivity to parvovirus H-1 was different. H-1 had inhibitory effect on epithelial cells of hepatoma tissue but without any significant effect on fibroblasts simultaneously, H-l had no effect on epithelial cells and fibroblasts of parahepatoma tissue. Further investigation of the relationship between parvovirus and hepatoma would be helpful not only in elucidating the mechanism of carcinogenesis and its suppression but also in the search of new approach for the treatment of hepatoma. 展开更多
关键词 PRELIMINARY COMPARISON OF SENSITIVITY TOWARD PARVO VIRUS H-1 OF HUMAN HEP ATOM A CELLS AND PARAHEPATOMA TISSUE
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Significance of Caucasian Sections for Working out Carbon-Isotope Standard for Upper Permian and Lower Triassic (Induan) and Their Correlation with the Permian of North-Eastern Russia
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作者 Yuri D Zakharov Alexander S Biakov +1 位作者 Aymon Baud Heinz Kozur 《Journal of China University of Geosciences》 SCIE CSCD 2005年第2期141-151,共11页
Data obtained on conodont distribution in the Permian-Triassic Sovetashen Section of Transcaucasia provide further limitations on the age of the carbon-isotopic anomalies discovered by Baud et al. (1989). The signific... Data obtained on conodont distribution in the Permian-Triassic Sovetashen Section of Transcaucasia provide further limitations on the age of the carbon-isotopic anomalies discovered by Baud et al. (1989). The significance of Caucasian sections for working out the carbon-isotope standard for the Upper Permian and Lower Triassic (Induan) is shown. Original data on carbon-isotope composition of bivalve and brachiopod shells from Permian sediments of North-Eastern Russia (Omolon and Okhotsk areas) have been obtained, which may be used for their correlation. 展开更多
关键词 Armenia North-Eastern Russia PERMIAN Triassic conodonts ammonoids bivalves brachiopods isotopic composition PALEOTEMPERATURES CORRELATION
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Endoscopic transluminal pancreatic necrosectomy using a self-expanding metal stent and high-flow water-jet system 被引量:10
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作者 István Hritz Roland Fejes +5 位作者 András Székely Iván Székely László Horváth gnes Sárkány ron Altorjay László Madácsy 《World Journal of Gastroenterology》 SCIE CAS 2013年第23期3685-3692,共8页
Walled-off pancreatic necrosis and a pancreatic abscess are the most severe complications of acute pancreatitis. Surgery in such critically ill patients is often associated with significant morbidity and mortality wit... Walled-off pancreatic necrosis and a pancreatic abscess are the most severe complications of acute pancreatitis. Surgery in such critically ill patients is often associated with significant morbidity and mortality within the first few weeks after the onset of symptoms. Minimal invasive approaches with high success and low mortality rates are therefore of considerable interest. Endoscopic therapy has the potential to offer safe and effective alternative treatment. We report here on 3 consecutive patients with infected walled-off pancreatic necrosis and 1 patient with a pancreatic abscess who underwent direct endoscopic necrosectomy 19-21 d after the onset of acute pancreatitis. The infected pancreatic necrosis or abscess was punctured transluminally with a cystostome and, after balloon dilatation, a non-covered self-expanding biliary metal stent was placed into the necrotic cavity. Following stent deployment, a nasobiliary pigtail catheter was placed into the cavity to ensure continuous irrigation. After 5-7 d, the metal stent was removed endoscopically and the necrotic cavity was entered with a therapeutic gastroscope. Endoscopic debridement was performed via the simultaneous application of a high-flow water-jet system; using a flush knife, a Dormia basket, and hot biopsy forceps. The transluminal endotherapy was repeated 2-5 times daily during the next 10 d. Supportive care included parenteral antibiotics and jejunal feeding. All patients improved dramatically and with resolution of their septic conditions; 3 patients were completely cured without any further complications or the need for surgery. One patient died from a complication of prolonged ventilation severe bilateral pneumonia, not related to the endoscopic procedure. No procedure related complications were observed. Transluminal endoscopic necrosectomy with temporary application of a self-expanding metal stent and a high-flow water-jet system shows promise for enhancing the potential of this endoscopic approach in patients with walled-off pancreatic necrosis and/or a pancreatic abscess. 展开更多
关键词 Acute NECROTIZING pancreatitis Walled off PANCREATIC necrosis ENDOSCOPIC NECROSECTOMY Selfexpanding metal stent Water-jet SYSTEM
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Genetic changes of p53,K-ras,and microsatellite instability in gallbladder carcinoma in high-incidence areas of Japan and Hungary 被引量:9
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作者 Masayuki Nagahashi Yoichi Ajioka +10 位作者 Istvan Lang Zoltan Szentirmay Miklos Kasler Hiroto Nakadaira Naoyuki Yokoyama Gen Watanabe Ken Nishikura Toshifumi Wakai Yoshio Shirai Katsuyoshi Hatakeyama Masaharu Yamamoto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第1期70-75,共6页
AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary. METHODS: We examined 42 cases of gallbladder carcinom... AIM: To disclose geographic differences in genetic changes involved in gallbladder carcinogenesis between two distinct high-incidence areas of Japan and Hungary. METHODS: We examined 42 cases of gallbladder carcinoma: 22 Japanese and 20 Hungarian cases, p53 mutations at exons 5 to 8 and K-ras mutations at codon 12 were tested by direct sequencing. Microsatellite instability was determined from fluorescent dye-labeled PCR amplifications of flve-microsatellite markers (BAT-25, BAT-26, D2S123, DSS346, and D17S250). RESULTS: Mutations of p53 were detected in 11 of 22 Japanese cases and 6 of 18 Hungarian cases (11/22 vs 6/18, P = 0.348). Transition at CpG sites was found in none of 11 Japanese cases and 2 of 6 Hungarian cases; the difference was marginally significant (0/11 vs 2/6,P = 0.110). K-ras mutations were detected in only one of the Hungarian cases. Eight of 19 (42.1%) ]apanese cases were MSI-high (presence of novel peaks in more than one of the five loci analyzed), whereas only 1 of 15 (6.7%) Hungarian cases was MSI-high (P = 0.047). CONCLUSION: It appears that the p53 mutations and MSI differ in patients with gallbladder carcinoma between two distinct high-incidence areas. Geographic variation might exist in the process of gallbladder carcinogenesis. 展开更多
关键词 GALLBLADDER Gallbladder Neoplasms K-RAS Microsatellite instability P53
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Benefits of implementing a rapid access clinic in a high-volume inflammatory bowel disease center:Access, resource utilization and outcomes 被引量:1
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作者 Sofia Nene Lorant Gonczi +11 位作者 Zsuzsanna Kurti Isabelle Morin Kelly Chavez Christine Verdon Jason Reinglas Rita Kohen Talat Bessissow Waqqas Afif Gary Wild Ernest Seidman Alain Bitton Peter Laszlo Lakatos 《World Journal of Gastroenterology》 SCIE CAS 2020年第7期759-769,共11页
BACKGROUND Emergency situations in inflammatory bowel diseases(IBD)put significant burden on both the patient and the healthcare system.AIM To prospectively measure Quality-of-Care indicators and resource utilization ... BACKGROUND Emergency situations in inflammatory bowel diseases(IBD)put significant burden on both the patient and the healthcare system.AIM To prospectively measure Quality-of-Care indicators and resource utilization after the implementation of the new rapid access clinic service(RAC)at a tertiary IBD center.METHODS Patient access,resource utilization and outcome parameters were collected from consecutive patients contacting the RAC between July 2017 and March 2019 in this observational study.For comparing resource utilization and healthcare costs,emergency department(ED)visits of IBD patients with no access to RAC services were evaluated between January 2018 and January 2019.Time to appointment,diagnostic methods,change in medical therapy,unplanned ED visits,hospitalizations and surgical admissions were calculated and compared.RESULTS 488 patients(Crohn’s disease:68.4%/ulcerative colitis:31.6%)contacted the RAC with a valid medical reason.Median time to visit with an IBD specialist following the index contact was 2 d.Patients had objective clinical and laboratory assessment(C-reactive protein and fecal calprotectin in 91%and 73%).Fast-track colonoscopy/sigmoidoscopy was performed in 24.6%of the patients,while computed tomography/magnetic resonance imaging in only 8.1%.Medical therapy was changed in 54.4%.ED visits within 30 d following the RAC visit occurred in 8.8%(unplanned ED visit rate:5.9%).Diagnostic procedures and resource utilization at the ED(n=135 patients)were substantially different compared to RAC users:Abdominal computed tomography was more frequent(65.7%,P<0.001),coupled with multiple specialist consults,more frequent hospital admission(P<0.001),higher steroid initiation(P<0.001).Average medical cost estimates of diagnostic procedures and services per patient was$403 CAD vs$1885 CAD comparing all RAC and ED visits.CONCLUSION Implementation of a RAC improved patient care by facilitating easier access to IBD specific medical care,optimized resource utilization and helped avoiding ED visits and subsequent hospitalizations. 展开更多
关键词 Crohn’s disease Ulcerative colitis Rapid access Quality-of-care Emergency department
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Aspects of high-performance and bio-acceptable magnetic nanoparticles for biomedical application 被引量:1
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作者 Preeti Kush Parveen Kumar +1 位作者 Ranjit Singh Ajeet Kaushik 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第6期704-737,共34页
This review covers extensively the synthesis&surface modification,characterization,and application of magnetic nanoparticles.For biomedical applications,consideration should be given to factors such as design stra... This review covers extensively the synthesis&surface modification,characterization,and application of magnetic nanoparticles.For biomedical applications,consideration should be given to factors such as design strategies,the synthesis process,coating,and surface passivation.The synthesis method regulates post-synthetic change and specific applications in vitro and in vivo imaging/diagnosis and pharmacotherapy/administration.Special insights have been provided on biodistribution,pharmacokinetics,and toxicity in a living system,which is imperative for their wider application in biology.These nanoparticles can be decorated with multiple contrast agents and thus can also be used as a probe for multi-mode imaging or double/triple imaging,for example,MRI-CT,MRI-PET.Similarly loading with different drug molecules/dye/fluorescent molecules and integration with other carriers have found application not only in locating these particles in vivo but simultaneously target drug delivery/hyperthermia inside the body.Studies are underway to collect the potential of these magnetically driven nanoparticles in various scientific fields such as particle interaction,heat conduction,imaging,and magnetism.Surely,this comprehensive data will help in the further development of advanced techniques for theranostics based on high-performance magnetic nanoparticles and will lead this research area in a new sustainable direction. 展开更多
关键词 MAGNETISM Synthesis Characterization Delivery Imaging BIODISTRIBUTION PHARMACOKINETIC
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Theoretical and experimental study of phase transformation and twinning behavior in metastable high-entropy alloys 被引量:4
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作者 Zhibiao Yang Song Lu +3 位作者 Yanzhong Tian Zijian Gu Jian Sun Levente Vitos 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第4期161-168,共8页
Combined theoretical and experimental efforts are put forward to study the critical factors influencing deformation mode transitions in face-centered cubic materials.We revisit the empirical relationship between the s... Combined theoretical and experimental efforts are put forward to study the critical factors influencing deformation mode transitions in face-centered cubic materials.We revisit the empirical relationship between the stacking fault energy(SFE)and the prevalent deformation mechanism.With ab initio calculated SFE,we establish the critical boundaries between various deformation modes in the model Cr-Co-Ni solid solution alloys.Satisfying agreement between theoretical predictions and experimental observations are reached.Our findings shield light on applying quantum mechanical calculations in designing transformation-induced plasticity and twinning-induced plasticity mechanisms for achieving advanced mechanical properties. 展开更多
关键词 Metastable alloys Stacking fault energy TWINNING Martensitic transformation Co-Cr-Ni alloys
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Basic Magmatic Formations within the Eastern Part of the Bukk Mountains, North-East Hungary
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作者 Adam Bartok 《Journal of Earth Science and Engineering》 2015年第4期221-229,共9页
The macro- and microscopic results were that this body of basalt tectonically heavily loaded, strongly altered by clay minerals and characterized by hydro-metasomatic alteration. The geochemical analyzes revealed that... The macro- and microscopic results were that this body of basalt tectonically heavily loaded, strongly altered by clay minerals and characterized by hydro-metasomatic alteration. The geochemical analyzes revealed that the original magma could be a mantle origin of high iron and magnesium containing basalt (tholeiites, 10%-15%). As regards to the palaeogeographic environment, it can be said that due to the periodic sea flooding, it pushed into a lower area, covered with sediment where the surrounding areas were highlighted (biikkszentkereszt and bukkszentlaszl6 tufts). 展开更多
关键词 Szinva metabasalt formation Bttkkian magmatism upper szinva source region metabasalt tholeiitic magma intracontinental volcanism.
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Children and Workers Well-Being in Belgian French-Speaking Primary Schools during the COVID-19 Pandemic
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作者 Kelly Cremer Julie Frère +6 位作者 Olga Chatzis Benoît Kabamba Florence Renard Mathilde De Keukeleire Ricardo De Mendonca Dimitri Van der Linden Annie Robert 《Health》 2023年第6期676-694,共19页
Purpose: During the COVID-19 pandemic, a significant number of measures were taken worldwide to limit the transmission of SARS-CoV-2, and in many ways, changed human life. All these measures had harmful consequences a... Purpose: During the COVID-19 pandemic, a significant number of measures were taken worldwide to limit the transmission of SARS-CoV-2, and in many ways, changed human life. All these measures had harmful consequences and impacted the well-being of many people. Children were one of the most vulnerable groups. We conducted the present study to assess children’s and staff’s well-being in French-speaking primary schools in Belgium during the COVID-19 pandemic. Methods: A 37-question questionnaire for each child based on the Revised Children’s Manifest Anxiety Scale (RCMAS), and a 14-question questionnaire for each staff based on the Hospital Anxiety and Depression (HAD) scale was undertaken in order to assess the well-being. Multiple logistic regressions were performed to assess the relationship between RCMAS or HAD and other explanatory variables. Staff reported their perception of their current life and their future life in 5 years on a Visual Analogue Scale (VAS). Results: A total of 231 children and 221 staff in 11 primary schools answered the well-being questionnaire between January and May 2021. 53% (122/231) of children had symptoms of anxiety. Girls reported more anxiety symptoms than boys (≥10: 59%;Adj OR = 2.25;95% CI [1.28;4.03]). 52% (120/231) of children had a definite state of social desirability. According to age, the youngest (6 - 7 years) children were more likely to have social desirability (≥5: 71%;Adj OR = 3.44;95% CI [1.53;8.09]) compared to the oldest (10 - 12 years). Children who did not practice outdoor/street activities were more likely to have social desirability (≥5: 60%;Adj OR = 2.59;95% CI [1.38;4.99]). In schools with a higher local incidence of SARS-CoV-2, children were more likely to have social desirability (≥5: 64%;Adj OR = 2.15;95% CI [1.13;4.17]). In schools with a lower socioeconomic status, children were more likely to have social desirability (≥5: 72%;Adj OR = 2.74;95% CI [1.23;6.37]). Higher RCMAS anxiety (r = −0.18;p −0.23;p −0.20;p Conclusion: Our results showed that the well-being of children was impacted during the COVID-19 pandemic. Special attention must be focused on the most vulnerable groups, as the consequences can be catastrophic in the long term. 展开更多
关键词 COVID-19 WELL-BEING CHILDREN SCHOOLS
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SARS-CoV-2 Antibody Seroprevalence in Children and Workers from Belgian French-Speaking Primary Schools
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作者 Kelly Cremer Julie Frère +6 位作者 Olga Chatzis Ricardo De Mendonca Benoît Kabamba Florence Renard Mathilde De Keukeleire Dimitri Van der Linden Annie Robert 《Health》 2023年第9期917-937,共21页
Purpose: During the COVID-19 pandemic, closing schools was discussed to limit the virus transmission, despite a lack of evidence on the role of young children in the virus spread. We undertook a study among Belgian pr... Purpose: During the COVID-19 pandemic, closing schools was discussed to limit the virus transmission, despite a lack of evidence on the role of young children in the virus spread. We undertook a study among Belgian primary schools to assess the SARS-CoV-2 antibody seroprevalence and its relationship with local incidence, school size, and socioeconomic status (SES). Methods: Schools were purposively selected using three criteria: an area with either a low or a high COVID-19 incidence, either a small or a large size, and either a low or a high SES. 932 (/2488, 38%) children and 242 (/444, 55%) staff signed informed consent. COVID-19 antibodies were tested using rapid finger prick tests. Results: Children participation was positively correlated with staff (r = +0.33;95% CI [−0.34;0.78]), and strongly with SES (r = +0.81;95% CI [0.40;0.95]). Seroprevalence was 21% in children (191/922) and 25% in staff (61/240). Seroprevalence did not correlate with local cumulative incidence (children: r = +0.06;95% CI [−0.59;0.67];staff: r = +0.26;95% CI [−0.40;0.74]). In staff, seroprevalence was higher in schools with higher SES (r = +0.37;95% CI [−0.29;0.79]), but not in children (r = −0.10;95% CI [−0.66;0.53]). Conclusion:The lower seroprevalence in children suggests they are lower transmitters than adults, but poor socioeconomic levels were less representative. 展开更多
关键词 SARS-CoV-2 CHILDREN SCHOOLS SEROPREVALENCE Socioeconomic Status Belgium
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Phenol in High-mass Star-forming Regions
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作者 Rana Ghosh Milan Sil +5 位作者 Suman Kumar Mondal Prasanta Gorai Dipen Sahu Rahul Kumar Kushwaha Bhalamurugan Sivaraman Ankan Das 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第6期256-268,共13页
Phenol,which belongs to the C_(6)H_(6)O isomeric group,is the simplest molecule in the family of alcohol of the aromatic series.Although phenol has yet to be detected in the interstellar medium,a tentative identificat... Phenol,which belongs to the C_(6)H_(6)O isomeric group,is the simplest molecule in the family of alcohol of the aromatic series.Although phenol has yet to be detected in the interstellar medium,a tentative identification was reported toward the Orion KL hot core using the IRAM-30 m line survey.To explore some more species of this isomeric group,we consider ten species to study the fate of their astronomical detection.It is noticed that phenol is the most energetically favorable isomer of this group.In contrast,propargyl ether is the least favorable(having relative energy~103kcal mol^(-1)compared to phenol)species of this group.So far,the studies associated with the formation of phenol are heavily concentrated on combustion chemistry.Here,we suggest a few key reactions(C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O,C_(6)H_(6)+O→C_(6)H_(5)OH,C_(6)H_(6)+H→C_(6)H_(5)+H_(2),and C_(6)H_(5)+OH→C_(6)H_(5)OH+hν)for the formation of phenol.All these pathways are included in a large gas-grain chemical network to study its formation in high mass star-forming regions and dark cloud environments.It is noticed that the phenyl(-C_(6)H_(5))formation by the ice-phase hydrogen abstraction reaction of benzene(i.e.,C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O if allowed at~10 K)could serve as the starting point for the formation of phenol in the gas phase by radiative association reaction C_(6)H_(5)+OH→C_(6)H_(5)OH+hν.The gasphase reaction C_(6)H_(6)+O→C_(6)H_(5)OH significantly contributes to the formation of phenol,when the ice-phase reaction C_(6)H_(6)+OH→C_(6)H_(5)+H_(2)O is not considered at low temperature.Band 4 ALMA archival data of a hot molecular core,G10.47+0.03,are analyzed.It yields an upper limit on phenol abundance of 5.19×10^(-9).Our astrochemical model delivers an upper limit on phenol abundance of~2.20×10^(-9)in the hot molecular core,whereas its production in the dark cloud is not satisfactory. 展开更多
关键词 astrochemistry-ISM abundances-ISM molecules-(ISM:)evolution
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ECG and Echocardiographic Findings of Female Hypertension (fHTN) in the Cardiology Department of the University Hospital Gabriel Touré (UH-GT)
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作者 Hamidou Oumar Bâ Ibrahima Sangaré +19 位作者 Youssouf Camara Kassim Kamaté Tawoufik Tchedre Georges Rosario Christian Millogo Djénébou Traoré Noumou Sidibé Fousseyni Samassékou Massama Konaté Coumba Thiam Doumbia Asmaou Maiga Réné-Marie Dakouo Hamidou Camara Adama Sogodogo Boubacar Diarra Mamadou Touré Boubacar Sonfo Aladji Traoré Mamadou Diakité Ilo Bella Diall Ichaka Menta 《World Journal of Cardiovascular Diseases》 2023年第10期646-656,共11页
Introduction: In our setting there is a lack of publications on female hypertension in general population motivating this study to look for electro- and echocardiographic findings of female hypertension. Methods: We p... Introduction: In our setting there is a lack of publications on female hypertension in general population motivating this study to look for electro- and echocardiographic findings of female hypertension. Methods: We performed a cross-sectional study during 6 months in the cardiology department of the UH-GT including 324 female patients aged 18 and more seen in the outpatient unit and by whom the diagnosis of hypertension was set. All patients consented to be study participants after receiving clearly information about the study and that care giving will not be affected by their eventual refusal. Data collection has been done with all needed confidentiality rules. A survey formular was used to collect data in order to record them in an Access database. Analysis was done using IBM SPSS software. Quantitative data are presented as mean with standard deviation and qualitative as proportion. Level of significance for statistic test was set at 5%. Results: During the study time 324 among 524 hypertensive patients visited our outpatient unit giving a prevalence of fHTN of 61.8%. The means for age, body mass index (BMI) in female hypertensive patients were respectively 52 ± 14.461 years and 27.35 ± 06.585 Kg/m<sup>2</sup>. Main ECG findings were left ventricular hypertrophy (LVH) and sinus tachycardia with respectively 93.6% and 46.4% followed by isolated ventricular extrasystole with 33.7%. Echocardiography findings included LVH, relative wall thickness (RWT) and reduced ejection fraction (EF) in respectively 41.05%, 37.35% and 21.91%. The left ventricular mass (LV) mass and geometry were abnormal in 44.4% and 37.3%. Remodeling as geometry modification (18.2%) and mitral flow Type 2 (90.4%) have been the most abnormal findings. Conclusion: Hypertension induced modifications mainly LVH in ECG and Echocardiography in female patients less than encountered among male hypertensive patients. 展开更多
关键词 HYPERTENSION FEMALE ECG Echocardiography MALI
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Flexible,tough and high-performing ionogels for supercapacitor application
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作者 Paulina Pietrzyk-Thel Amrita Jain +6 位作者 Kamil Bochenek Monika Michalska Michał Basista Tamas Szabo Peter B.Nagy Anna Wolska Marcin Klepka 《Journal of Materiomics》 2025年第1期17-29,共13页
Ionogels are an attractive class of materials for smart and flexible electronics and are prepared from the combination of a polymer and ionic liquid which is entrapped in this matrix.Ionogels provide a continuous cond... Ionogels are an attractive class of materials for smart and flexible electronics and are prepared from the combination of a polymer and ionic liquid which is entrapped in this matrix.Ionogels provide a continuous conductive phase with high thermal,mechanical,and chemical stability.However,because of the higher percentage of ionic liquids it is difficult to obtain an ionogel with high ionic conductivity and mechanical stability,which are very important from an application point of view.In this work,ionogel films with high flexibility,excellent ionic conductivity,and exceptional stability were prepared using polyvinyl alcohol as the host polymer matrix and 1-ethyl-3-methylimidazolium hydrogen sulfate as the ionic liquid using water as the solvent for energy storage application.The prepared ionogel films exhibited good mechanical stability along with sustaining strain of more than 100%at room temperature and low temperature,the ability to withstand twisting up to 360and different bending conditions,and excellent ionic conductivity of 5.12×10^(-3) S/cm.The supercapacitor cell fabricated using the optimized ionogel film showed a capacitance of 39.9 F/g with an energy and power densities of 5.5 W,h/kg and 0.3 kW/kg,respectively confirming the suitability of ionogels for supercapacitor application. 展开更多
关键词 Ionic liquid Gel polymer electrolyte Ionic conductivity 1-Ethyl-3-methylimidazolium hydrogen sulfate SUPERCAPACITORS
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High-Repetition-Rate Attosecond Extreme Ultraviolet Beamlines at ELI ALPS for Studying Ultrafast Phenomena 被引量:1
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作者 Mojtaba Shirozhan Sudipta Mondal +24 位作者 Tímea Grósz Balázs Nagyillés Balázs Farkas Arjun Nayak Naveed Ahmed Indranuj Dey Shivani Choudhary De Marco Kwinten Nelissen Miklos Kiss Lénárd Gulyás Oldal Tamás Csizmadia Zoltán Filus Massimo De Marco Saibabu Madas Mousumi Upadhyay Kahaly Dimitris Charalambidis Paraskevas Tzallas Elisa Appi Robin Weissenbilder PEng-Johnsson Anne L’Huillier Zsolt Diveki Balázs Major Katalin Varjú Subhendu Kahaly 《Ultrafast Science》 2024年第6期1-27,共27页
Advancements in light engineering have led to the creation of pulsed laser sources capable of delivering high-repetition-rate,high-power few-cycle laser pulses across a wide spectral range,enabling exploration of many... Advancements in light engineering have led to the creation of pulsed laser sources capable of delivering high-repetition-rate,high-power few-cycle laser pulses across a wide spectral range,enabling exploration of many fascinating nonlinear processes occurring in all states of matter.High-harmonic generation,one such process,which converts the low-frequency photons of the driver laser field into soft x-rays,has revolutionized atomic,molecular,and optical physics,leading to progress in attosecond science and ultrafast optoelectronics.The Extreme Light Infrastructure,Attosecond Light Pulse Source(ELI ALPS)facility pioneers state-of-the-art tools for research in these areas.This paper outlines the design rationale,capabilities,and applications of plasma-and gas-based high-repetition-rate(1 kHz to 100 kHz)attosecond extreme ultraviolet(XUV)beamlines developed at ELI ALPS,highlighting their potential for advancing various research fields. 展开更多
关键词 extreme ultraviolet attosecond science ul eli alps light engineering BEAMLINES pulsed laser sources ATTOSECOND high repetition rate
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基于叙事医学的医学人文素养提升——临床医学博士后项目探索 被引量:1
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作者 贾俊君 陈磊 +2 位作者 周雪莲 陈韶华 刘有恃 《叙事医学》 2025年第1期45-48,共4页
为了有效提升临床医学博士后的人文素养,浙江大学医学院针对临床博士后项目设计并实施了一套基于叙事医学的教育体系。该体系由理论教学与实践操作两部分组成。理论部分涵盖了叙事医学导论、叙事医学与医患沟通、平行病历写作、基于叙... 为了有效提升临床医学博士后的人文素养,浙江大学医学院针对临床博士后项目设计并实施了一套基于叙事医学的教育体系。该体系由理论教学与实践操作两部分组成。理论部分涵盖了叙事医学导论、叙事医学与医患沟通、平行病历写作、基于叙事医学的教学与科研、叙事医学与医患共同决策、大健康语境下的叙事医学、做好生命末期的摆渡人7个主题。实践活动部分则包括了平行病历写作练习和职业素养竞赛。这一系列课程的设置,旨在以叙事医学为切入点,增强临床医学博士后的综合人文素质,探索一条培养具备深厚人文关怀精神的高级医疗人才的新路径。 展开更多
关键词 临床医学博士后 叙事医学 医学人文素养
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不同连作年限对番茄设施土壤细菌群落与土壤环境的影响
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作者 王娟 王媛媛 +4 位作者 刘力勇 谭巍 王志伟 许春梅 刘思宇 《中国蔬菜》 北大核心 2025年第6期101-109,共9页
为探究设施番茄不同连作年限土壤微生物群落结构变化及其与土壤化学性质的关系,采用高通量测序技术对连续种植番茄1年(C1)、4年(C4)、7年(C7)和10年(C10)的土壤细菌微生物群落进行了测定,并测定了土壤化学性质及其与土壤微生物的相关性... 为探究设施番茄不同连作年限土壤微生物群落结构变化及其与土壤化学性质的关系,采用高通量测序技术对连续种植番茄1年(C1)、4年(C4)、7年(C7)和10年(C10)的土壤细菌微生物群落进行了测定,并测定了土壤化学性质及其与土壤微生物的相关性。结果表明:与C1处理相比,C4、C7和C10处理土壤碱解氮、有效磷、速效钾含量及土壤微生物多样性的Shannon指数和Simpson指数均显著降低。土壤中细菌群落组成发生改变,在细菌群落门水平上,与C1处理相比,C4、C7和C10处理土壤中酸杆菌门(Acidobacteria)和候选菌门(Rokubacteria)的相对丰度均显著增加,而C4和C10处理土壤中厚壁菌门(Firmicutes)和髌骨细菌门(Patescibacteria)的相对丰度均显著减少。在细菌群落属水平上,与C1处理相比,C4处理土壤中MND1、Rubrobacter、RB41、67-14、硝化螺旋菌属(Nitrospira)、MBA2-108、Rokubacteriales、bacteriap25和IMCC26256的相对丰度显著增加,Ellin6067、Haliangium、A4b的相对丰度显著减少;C7处理土壤中鞘氨醇单胞菌属(Sphingomonas)、Rubrobacter、67-14、RB41、Rokubacteriales、芽单胞菌属(Gaiella)和Blastococcus相对丰度显著增加,SBR1031、Ellin6067、Haliangium、A4b的相对丰度显著减少;C10处理土壤中GittGS-136的相对丰度显著减少。随着种植年限的增加,OTUs的相对丰度上有显著改变,其中OTU_2108、OTU_13084、OTU_105436、OTU_23455、OTU_52896、OTU_58127、OTU_46318、OTU_51042呈现先增加后减少的趋势。冗余分析表明,土壤EC值、有效磷含量、速效钾含量是影响连作土壤细菌优势属分布的主要因素。综上,长期连续单一种植导致了土壤环境改变,土壤养分流失,并严重影响了土壤微生物群落。 展开更多
关键词 番茄 连作 土壤细菌群落 土壤化学性质 高通量测序
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基于内模控制框架的机电复合传动系统扭转振动抑制策略
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作者 刘辉 杨殿钊 +5 位作者 高普 张伟 焦佳新 严琦 关双元 项昌乐 《机械工程学报》 北大核心 2025年第16期204-216,共13页
机电复合传动系统(Electro-mechanical transmission,EMT)是一种将电驱动系统和传动系统集成于一体的复杂系统,其特性在特殊工况下会迅速恶化,该问题可通过主动扭振抑制策略有效解决。然而,大多减振策略基于过度简化的模型开展,导致其... 机电复合传动系统(Electro-mechanical transmission,EMT)是一种将电驱动系统和传动系统集成于一体的复杂系统,其特性在特殊工况下会迅速恶化,该问题可通过主动扭振抑制策略有效解决。然而,大多减振策略基于过度简化的模型开展,导致其与实际场景的匹配性差。另外,大多控制策略在改善振动情况时易造成响应延迟问题。为改善上述问题,搭建了EMT27自由度扭转振动模型,提出一种基于模态贡献评价和刚度灵敏度分析的模型降阶方法,实现将模型由27个自由度降阶至5个自由度且使0~100 Hz模型相似度高达99.89%的效果。针对扭振强抑制与响应小延迟的固有矛盾问题,探究驱动转矩激发EMT扭振的机理,优化驱动转矩频域中的主频和能量分布,设计干扰至半轴转矩的理想传递特性,最终基于降阶模型提出一种的EMT扭振抑制内模控制策略(Internal model control-based torsional vibration suppression,IMC-TVS)。经仿真与试验验证,IMC-TVS相比PID和线性二次型调节器在扭振抑制方面具有较好的先进性和实时性。 展开更多
关键词 履带车辆 机电复合传动系统 扭转振动 模型降阶 内模控制
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