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An Ultralytics YOLOv8-Based Approach for Road Detection in Snowy Environments in the Arctic Region of Norway 被引量:2
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作者 Aqsa Rahim Fuqing Yuan Javad Barabady 《Computers, Materials & Continua》 2025年第6期4411-4428,共18页
In recent years,advancements in autonomous vehicle technology have accelerated,promising safer and more efficient transportation systems.However,achieving fully autonomous driving in challenging weather conditions,par... In recent years,advancements in autonomous vehicle technology have accelerated,promising safer and more efficient transportation systems.However,achieving fully autonomous driving in challenging weather conditions,particularly in snowy environments,remains a challenge.Snow-covered roads introduce unpredictable surface conditions,occlusions,and reduced visibility,that require robust and adaptive path detection algorithms.This paper presents an enhanced road detection framework for snowy environments,leveraging Simple Framework forContrastive Learning of Visual Representations(SimCLR)for Self-Supervised pretraining,hyperparameter optimization,and uncertainty-aware object detection to improve the performance of YouOnly Look Once version 8(YOLOv8).Themodel is trained and evaluated on a custom-built dataset collected from snowy roads in Tromsø,Norway,which covers a range of snow textures,illumination conditions,and road geometries.The proposed framework achieves scores in terms of mAP@50 equal to 99%and mAP@50–95 equal to 97%,demonstrating the effectiveness of YOLOv8 for real-time road detection in extreme winter conditions.The findings contribute to the safe and reliable deployment of autonomous vehicles in Arctic environments,enabling robust decision-making in hazardous weather conditions.This research lays the groundwork for more resilient perceptionmodels in self-driving systems,paving the way for the future development of intelligent and adaptive transportation networks. 展开更多
关键词 Autonomous vehicles self-driving vehicles road detection snow-covered roads YOLOv8 road detection using segmentation
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The influence of physiobiomechanical parameters,technical aspects of shooting,and psychophysiological factors on biathlon performance:A review 被引量:10
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作者 Marko S.Laaksonen Thomas Finkenzeller +1 位作者 Hans-Christer Holmberg Gerold Sattlecker 《Journal of Sport and Health Science》 SCIE 2018年第4期394-404,共11页
The biathlon,an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship,entails considerable physiological demands,as well as fine motor control while shooting after intense exercise and... The biathlon,an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship,entails considerable physiological demands,as well as fine motor control while shooting after intense exercise and under mental pressure.Although much of our knowledge about cross-country skiing is probably also applicable to the biathlon,carrying the rifle and shooting under stress make this discipline somewhat unique.The present review summarizes and examines the scientific literature related to biathlon performance,with a focus on physiological and biomechanical factors and shooting technique,as well as psychophysiological aspects of shooting performance.We conclude with suggestions for future research designed to extend our knowledge about the biathlon,which is presently quite limited.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.(http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Cortical activity Gaze behavior Postural balance SKIING TRIGGERING
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Changes in Barents Sea ice Edge Positions in the Last 440 years: A Review of Possible Driving Forces 被引量:2
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作者 Nils-Axel Mö rner +2 位作者 Jan-Erik Solheim Ole Humlum Stig Falk-Petersen 《International Journal of Astronomy and Astrophysics》 2020年第2期97-164,共68页
This is the first report of the Barents Sea Ice Edge (BIE) project. The BIE position has varied between latitude 76<span style="white-space:nowrap;">&deg;</span>N and above 82<span style=&... This is the first report of the Barents Sea Ice Edge (BIE) project. The BIE position has varied between latitude 76<span style="white-space:nowrap;">&deg;</span>N and above 82<span style="white-space:nowrap;">&deg;</span>N during the last 440 years. During the period 10,000 to 6000 years ago, Arctic climate was significantly warmer than today. We review various oceanic and atmospheric factors that may have an effect on the BIE position. The Gulf Stream beat with respect to alternations in flow intensity and N-S distribution plays a central role for the changes in climate and BIE position during the last millennium. This occurred in combination with external forcing from total solar irradiation, Earth’s shielding strength, Earth’s geomagnetic field intensity, Earth’s rotation, jet stream changes;all factors of which are ultimately driven by the planetary beat on the Sun, the Earth and the Earth-Moon system. During the last 20 years, we see signs of changes and shifts that may signal the end of the late 20<sup>th</sup> century warm period. The BIE position is likely to start advancing southward in next decade. 展开更多
关键词 Barents Sea Ice Edge Cyclic Changes Gulf Stream Beat Planetary-Solar Forcing
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Challenges in the Detection and Attribution of Northern Hemisphere Surface Temperature Trends Since 1850 被引量:1
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作者 Ronan Connolly Willie Soon +17 位作者 Michael Connolly Sallie Baliunas Johan Berglund C.J.Butler Rodolfo Gustavo Cionco Ana G.Elias Valery M.Fedorov Hermann Harde Gregory W.Henry Douglas V.Hoyt Ole Humlum David R.Legates Nicola Scafetta Jan-Erik Solheim LászlóSzarka Víctor M.Velasco Herrera Hong Yan Weijia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第10期367-386,共20页
Since 2007,the Intergovernmental Panel on Climate Change(IPCC)has heavily relied on the comparison between global climate model hindcasts and global surface temperature(ST)estimates for concluding that post-1950s glob... Since 2007,the Intergovernmental Panel on Climate Change(IPCC)has heavily relied on the comparison between global climate model hindcasts and global surface temperature(ST)estimates for concluding that post-1950s global warming is mostly human-caused.In Connolly et al.,we cautioned that this approach to the detection and attribution of climate change was highly dependent on the choice of Total Solar Irradiance(TSI)and ST data sets.We compiled 16 TSI and five ST data sets and found by altering the choice of TSI or ST,one could(prematurely)conclude anything from the warming being“mostly human-caused”to“mostly natural.”Richardson and Benestad suggested our analysis was“erroneous”and“flawed”because we did not use a multilinear regression.They argued that applying a multilinear regression to one of the five ST series re-affirmed the IPCC's attribution statement.They also objected that many of the published TSI data sets were out-of-date.However,here we show that when applying multilinear regression analysis to an expanded and updated data set of 27 TSI series,the original conclusions of Connolly et al.are confirmed for all five ST data sets.Therefore,it is still unclear whether the observed warming is mostly human-caused,mostly natural or some combination of both. 展开更多
关键词 Sun:activity (Sun:)solar-terrestrial relations EARTH
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Research trends of clinical studies on acupuncture protocols over the past 20 years:a bibliometric analysis
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作者 Zhi-Qiang Li Xue-Feng Wang +3 位作者 Heng Yin Feng Cao Yu-Tong Fei Jian-Ping Liu 《Integrative Medicine Discovery》 2024年第28期1-14,共14页
Background:Acupuncture protocols are essential as they guide study design and improve the quality of clinical trial,thus preventing avoid research waste.Given the increasing number of publications on acupuncture proto... Background:Acupuncture protocols are essential as they guide study design and improve the quality of clinical trial,thus preventing avoid research waste.Given the increasing number of publications on acupuncture protocols,this study aimed to assess the publications trends of acupuncture protocols over the past two decades and provided an overview for future research directions.Methods:Publications focusing on acupuncture protocols in clinical settings were retrieved and compiled from the Web of Science Core Collection spanning the period from 2004 to 2023.CiteSpace and Microsoft Excel software were used to analyze the relationship of publication with countries,institutions,authors,co-cited author,journals,references,keywords and other literature aspects.Results:This study analyzed 721 articles encompassing acupuncture protocols.A continuous yet fluctuating growth in publications volume were observed from 2004 to 2023.Notably,China stands at the forefront in contributing to acupuncture protocols,publishing 513 papers and demonstrating a high centrality score of 1.07 in cooperative network.Furthermore,China has fostered close collaborations with the USA and South Korea.Beijing University of Chinese Medicine(89),Zhishun Liu(36)and Trials(306)emerged as the top contributors in terms of institution,author,and journal,respectively.However,inter-institutional and author collaboration was relatively weak.Macpherson H was the most frequently cited author.High-frequency keywords included“randomized controlled trials”,“acupuncture”,“management”,“study protocol”,“quality of life”.Analysis of timeline diagram of keywords indicated that“functional dyspepsia”,“stroke”,“electroacupuncture”,and“colorectal cancer”were the research development trends and focus.Conclusion:Clinical acupuncture protocols have experienced robust development over the past two decades,with current research hotspots focusing on disease management and quality of life,which remain key research concerns.Moreover,we advocate for researchers to publish acupuncture protocols,which remain key research concerns.This approach allows for thorough pre-study planning of methodologies and objectives,enhancing scientific rigor through peer review,thereby laying the foundation for conducting high-quality research. 展开更多
关键词 ACUPUNCTURE PROTOCOL BIBLIOMETRIC HOTSPOTS CiteSpace
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The Ghana Project in Psychiatry: A Systematic Description of the Mental Health Services
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作者 Michael Atakora Mdala Ibrahim Emmanuel Asampong 《Open Journal of Psychiatry》 2020年第4期141-170,共30页
<strong>Introduction: </strong>Mental health is a neglected field within the health care system in Ghana. Studies and public education focusing on mental health remain low, leading to poor knowledge and aw... <strong>Introduction: </strong>Mental health is a neglected field within the health care system in Ghana. Studies and public education focusing on mental health remain low, leading to poor knowledge and awareness of mental health among the population. <strong>Objective:</strong> The overall aim of this study was to provide a systematic description of mental health services in Ghana. <strong>Methods:</strong> A snowball technique was used to select a total of 42 mental health professionals from six hospitals for interviews. A structured questionnaire was used for data collection. <strong>Results:</strong> Major findings of this study include inadequate human and material resources;poor knowledge of mental health among the population;weak coordination between general practitioners and mental health professionals;inadequate mental health services in schools and prisons. Additionally, 54.8% of respondents reported limited mental health educational materials, and most schools (54.8%) lacking trained resident mental health professionals. The main interventions for service delivery are taking over activities of daily living by nurses, problem assessment, and psychological interventions which achieved the same results (69%). A tendency to consult faith-based healers and prayer camps;a lack of mental health research capacity, specifically research focusing on policies;and weakness in the organization and decentralization of mental health services in Ghana are among the common challenges to seeking care. <strong>Conclusion: </strong>Public mental health education on available resources and services is important. Capacity research focusing on dissemination and implementation of mental health policies can serve as the basis for addressing mental health challenges and improving service delivery in Ghana. 展开更多
关键词 Mental Health Service RESOURCES ORGANIZATION DECENTRALIZATION DIFFERENTIATION
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Altitude and intensity characteristics of parametric instability excited by an HF pump wave near the fifth electron harmonic
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作者 吴军 吴健 +3 位作者 M T RIETVELD I HAGGSTROM 赵海生 许正文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第12期50-56,共7页
An ionospheric heating experiment involving an O mode pump wave was carried out at European Incoherent Scatter Scientific Association site in Troms?. The observation of the ultra high frequency radar illustrates the ... An ionospheric heating experiment involving an O mode pump wave was carried out at European Incoherent Scatter Scientific Association site in Troms?. The observation of the ultra high frequency radar illustrates the systematic variations of the enhanced ion line and plasma line in altitude and intensity as a function of the pump frequency. The analysis shows that those altitude variations are due to the thermal effect, and the intensity variations of the enhanced ion line are dependent on whether or not the enhanced ion acoustic wave satisfy the Bragg condition of radar. Moreover, a prediction that if the enhancement in electron temperature is suppressed,those systematic variations will be absent, is given. 展开更多
关键词 ionospheric heating fifth harmonic parameter instability altitude intensity
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Development of an Environmental Impact Methodology for Arctic Shipping:Exploring FMEA and STPA applications considering a Dynamic(varying)Baseline
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作者 Giacomo Stirpe Ove Tobias Gudmestad 《Sustainable Marine Structures》 2024年第2期15-41,共27页
Arctic shipping poses environmental risks due to the region’s fragile ecosystems and rapid climate changes.Effective risk assessment tools are needed to ensure sustainable expansion and to carry out environmental imp... Arctic shipping poses environmental risks due to the region’s fragile ecosystems and rapid climate changes.Effective risk assessment tools are needed to ensure sustainable expansion and to carry out environmental impact assessments.This paper explores applications of Failure Modes and Effects Analysis(FMEA)and Systems-Theoretic Process Analysis(STPA)coupled with the consequences of a“Dynamic baseline approach”for Arctic shipping environmental impact assessment.Shipping entails complex interactions between environmental,technical,human,and organizational factors.FMEA identifies failure modes and their effects through component-level analysis.STPA examines how unsafe control actions can emerge from interactions between system components.Combining these techniques with a dynamic(variable)baseline,accounting for inherent ongoing changing Arctic conditions,offers a robust methodology.A qualitative case study shows that prioritizing hazards by risk,yields highest concerns,as increased greenhouse gas emissions,black carbon deposition on ice and snow,and response delays to accidents represent some of the most important identified threats to the environment.The use of FMEA and STPA are complementary,and differences are highlighted.The methodology applied,should be representative for the qualitative risk analysis methodology,and while the findings are impacted by the perspectives of the authors,the process followed is intended to identify and rank risks in a consistent manner.Mitigations measures must be in place to target these issues.Constant monitoring of the changing ecological and socioeconomic Arctic baselines supports the responses.This methodology offers a starting point for systematically addressing environmental impact risks in the data-limited Arctic.Integrating failure modes and effect analysis,system theories and dynamic baselines,account for identification of the complex interactions,influencing environmental risks in this rapidly evolving region. 展开更多
关键词 Arctic shipping Environmental impact analysis Arctic baseline Dynamic baseline Risk analysis FMEA STPA Risk mitigation prioritization
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Characteristics and trends of bibliometric analysis on acupuncture:A cross-sectional study
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作者 Zhi-Qiang Li Hui-Juan Cao +9 位作者 Heng Yin Yue Jiang Xue-Feng Wang Chen Shen Kun Wu Zi-Yi Qi Mei-Ling Wang You-Zhu Su Ling-Yao Kong Jian-Ping Liu 《Integrative Medicine Discovery》 2025年第3期1-11,共11页
Background:The bibliometrics of acupuncture are growing rapidly.However,the absence of reporting guidelines may lead to significant duplication and waste,thereby undermining the research’s value.To address this,a kno... Background:The bibliometrics of acupuncture are growing rapidly.However,the absence of reporting guidelines may lead to significant duplication and waste,thereby undermining the research’s value.To address this,a knowledge mapping was generated based on published studies to investigate the characteristics of bibliometric studies on acupuncture and the extent of duplicate publications,with the overarching goal of providing a comprehensive overview of the knowledge structure in this field.Methods:This cross-sectional study used three databases(PubMed,Web of Science,and Scopus)to identify relevant studies up to May 1,2024.In addition,the reference lists were retrieved as a supplement.To track research trends,we employed Microsoft Excel and R software to extract,code,and analyze information.Study selection,data extraction,and validation were performed independently by at least two reviewers.The reporting quality of included studies was assessed using the Preliminary guideline for reporting bibliometric reviews of the biomedical literature(BIBLIO).Results:Among the 6,221 bibliometric reviews examined,113 relevant publications were identified,80 focusing on various diseases/conditions.The annual number of publications has gradually increased,with the output in the past four years being 3.52 times higher than that before 2020.China(106)and Chengdu University of Traditional Chinese Medicine(16)have the highest number of publications.The most prolific author is Fan-Rong Liang,with six articles.The first bibliometric study,by Hai-Yan Li,was published in 2010.Journal of Pain Research,with 36 articles,holds the most publications.The top three diseases:diseases of the nervous system;symptoms,signs,or clinical findings not elsewhere classified;and mental,behavioral,or neurodevelopmental disorders.There may be potential duplication in research on 13 diseases/conditions,notably stroke,migraine,pain/analgesia,cancer pain,shoulder pain,facial paralysis/bell’s palsy,chronic pain,and cognitive impairment.In BIBLIO,the most frequently missing items are issues/topics(item 2),quality assessment(item 11),and descriptive findings(item 13).Conclusion:This study demonstrates that acupuncture bibliometrics is actively utilized to identify dominant diseases/conditions,aiding scholars in understand the knowledge structure and main topics.Although the number of related studies is increasing,with an average of 25 studies annually,overlap in some areas highlights the need for adherence to reporting guidelines and careful topic selection to ensure truly valuable insights and knowledge contributions.The adherence to BIBLIO’s 20 proposed items across analyzed articles,highlighting important in reporting practices. 展开更多
关键词 cross-sectional study ACUPUNCTURE BIBLIOMETRICS evidence mapping
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The Rome consensus:good clinical trials for traditional medicine
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作者 Junhua Zhang Boli Zhang +26 位作者 Alice J.Fauci Myeong Soo Lee LSusan Wieland Iman Majd Terje Alræk Linda Zhong Sergio Bangrazi Aldo Liguori Jingqing Hu Yanming Xie Jianyuan Tang Zhongqi Yang Paolo Landini Annalisa Bucchi Weian Yuan Kam Wa Chan Filomena Petti Carlo Maria Giovanardi Jialiang He Rui Gao Baohe Wang Yuhong Huang Jia Liu Fang Lu Jianan Guo Pasquale Ricci Bo Pang 《Acupuncture and Herbal Medicine》 2025年第3期271-272,共2页
Traditional Medicine(TM),particularly Traditional Chinese Medicine(TCM),is an indispensable component of the global healthcare system,offering unique insights to modern medical science.Clinical efficacy is the bedrock... Traditional Medicine(TM),particularly Traditional Chinese Medicine(TCM),is an indispensable component of the global healthcare system,offering unique insights to modern medical science.Clinical efficacy is the bedrock for the inheritance and development of TM.To meet the growing demand for high-quality healthcare,it is imperative to integrate TM with modern technology to address the issue of insufficient evidence for the efficacy of TM. 展开更多
关键词 traditional medicine healthcare system traditional chinese medicine tcm traditional medicine tm particularly modern technology clinical trials traditional Chinese medicine clinical efficacy
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Associations of accelerometer-determined physical activity and sedentary behavior with sarcopenia and incident falls over 12 months in community-dwelling Swedish older adults 被引量:3
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作者 David Scott Jonas Johansson +3 位作者 Anoohya Gandham Peter R.Ebeling Peter Nordstrom Anna Nordstrom 《Journal of Sport and Health Science》 SCIE 2021年第5期577-584,共8页
Purpose:This study was aimed to determine associations of accelerometer-determined time and bouts of sedentary behavior,light physical activity(LPA),and moderate-to-vigorous PA(MVPA)with sarcopenia and incident falls ... Purpose:This study was aimed to determine associations of accelerometer-determined time and bouts of sedentary behavior,light physical activity(LPA),and moderate-to-vigorous PA(MVPA)with sarcopenia and incident falls over 12 months.Methods:A total of 3334 Swedish 70-year-olds were assessed for sarcopenia,as defined by the revised definition of the European Working Group on Sarcopenia in Older People.Assessments were based on low scores for appendicular lean mass(dual-energy X-ray absorptiometry),hand grip strength,and the Timed Up and Go test.For 7 days after baseline,total time and total number of bouts(≥10 min of continuous activity at a given intensity)of activity performed at sedentary,LPA,and MVPA intensities were assessed by accelerometer.Incident falls were self-reported 6 months and 12 months after baseline.Results:Only 1.8%of participants had probable or confirmed sarcopenia.After multivariable adjustment for other levels of activity,only greater MVPA time was associated with a decreased likelihood of having low appendicular lean mass,low hand grip strength,and slow Timed Up and Go time as defined by the European Working Group on Sarcopenia in Older People criteria(all p<0.05),and only MVPA time was associated with lower likelihood of probable or confirmed sarcopenia(odds ratio=0.80,95%confidence interval:0.71-0.91 h/week).Similar associations were identified for total number of bouts,with no evidence of threshold effects for longer duration of bouts of MVPA.A total of 14%of participants reported-1 fall,but neither total time nor bouts of activity was associated with incident falls(all p>0.05).Conclusion:Higher amounts of accelerometer-determined MVPA are consistently associated with a decreased likelihood of sarcopenia and its components,regardless of the length of bouts or amounts of sedentary behavior. 展开更多
关键词 ACCELEROMETER FALLS Older adults Physical activity SARCOPENIA
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Do patients with gastroesophageal reflux disease and somatoform tendencies benefit from antireflux surgery? 被引量:2
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作者 Hans Friedrich Fuchs Benjamin Babic +3 位作者 Karl-Hermann Fuchs Wolfram Breithaupt Gabor Varga Frauke Musial 《World Journal of Gastroenterology》 SCIE CAS 2019年第3期388-397,共10页
BACKGROUND The clinical presentation of gastroesophageal reflux disease(GERD) shows a large symptom variation also in different intensities among patients. As several studies have shown, there is a large overlap in th... BACKGROUND The clinical presentation of gastroesophageal reflux disease(GERD) shows a large symptom variation also in different intensities among patients. As several studies have shown, there is a large overlap in the symptomatic spectrum between proven GERD and other disorders such as dyspepsia, functional heartburn and/or somatoform disorders.AIM To prospectively evaluate the GERD patients with and without somatoform disorders before and after laparoscopic antireflux surgery.METHODS In a tertiary referral center for foregut surgery over a period of 3 years patients with GERD, qualifying for the indication of laparoscopic antireflux surgery, were investigated prospectively regarding their symptomatic spectrum in order to identify GERD and associated somatoform disorders. Assessment of symptoms was performed by an instrument for the evaluation of somatoform disorders[Somatoform Symptom Index(SSI) > 17]. Quality of life was evaluated by Gastrointestinal Quality of Life Index(GIQLI).RESULTS In 123 patients an indication for laparoscopic antireflux surgery was established and in 43 patients further medical therapy was suggested. The portion of somatoform tendencies in the total patient population was 20.48%(34 patients).Patients with a positive SSI had a preoperative GIQLI of 77(32-111). Patients with a normal SSI had a GIQLI of 105(29-140)(P < 0.0001). In patients with GERD the quality of life could be normalized from preoperative reduced values of GIQLI102(47-140) to postoperative values of 117(44-144). In patients with GERD and somatoform disorders, the GIQLI was improved from preoperative GIQLI 75(47-111) to postoperative 95(44-122)(P < 0.0043).CONCLUSION Patients with GERD and associated somatoform disorders have significantly worse levels of quality of life. The latter patients can also benefit from laparoscopic fundoplication, however they will not reach a normal level. 展开更多
关键词 GASTROESOPHAGEAL REFLUX DISEASE ANTIREFLUX surgery Laparoscopic fundoplication SOMATIZATION GASTROESOPHAGEAL REFLUX DISEASE symptoms
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Stimulated electromagnetic emissions spectrum observed during an X-mode heating experiment at the European Incoherent Scatter Scientific Association 被引量:2
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作者 Xiang Wang Chen Zhou +3 位作者 Tong Xu Farideh Honary Michael Rietveld Vladimir Frolov 《Earth and Planetary Physics》 CSCD 2019年第5期391-399,共9页
An extraordinary(X-mode)electromagnetic wave,injected into the ionosphere by the ground-based heating facility at Tromsφ,Norway,was utilized to modify the ionosphere on November 6,2017.The high-power high-frequency t... An extraordinary(X-mode)electromagnetic wave,injected into the ionosphere by the ground-based heating facility at Tromsφ,Norway,was utilized to modify the ionosphere on November 6,2017.The high-power high-frequency transmitter facility located at Tromsφ belongs to the European Incoherent Scatter Scientific Association.In the experiment,stimulated electromagnetic emission(SEE)spectra were observed.A narrow continuum occurred under cold-start conditions and showed an overshoot effect lasting several seconds.Cascading peaks occurred on both sides of the heating frequency only in the preconditioned ionosphere and also showed an overshoot effect.These SEE features are probably related to the ponderomotive process in the X-mode heating experiment and are helpful for understanding the physical mechanism that generated them during the X-mode heating experiment.The features observed in the X-mode heating experiments are novel and require further investigation. 展开更多
关键词 artificial ionosphere modification stimulated electromagnetic emissions extraordinary electromagnetic wave European Incoherent Scatter Scientific Association(EISCAT)
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How much has the Sun influenced Northern Hemisphere temperature trends?An ongoing debate 被引量:2
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作者 Ronan Connolly Willie Soon +20 位作者 Michael Connolly Sallie Baliunas Johan Berglund C.John Butler Rodolfo Gustavo Cionco Ana G.Elias Valery M.Fedorov Hermann Harde Gregory W.Henry Douglas V.Hoyt Ole Humlum David R.Legates Sebastian Liming Nicola Scafetta Jan-Erik Solheim Laszlo Szarka Harry van Loon Victor M.Velasco Herrera Richard C.Willson Hong Yan Weijia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第6期131-198,共68页
In order to evaluate how much Total Solar Irradiance(TSI)has influenced Northern Hemisphere surface air temperature trends,it is important to have reliable estimates of both quantities.Sixteen different estimates of t... In order to evaluate how much Total Solar Irradiance(TSI)has influenced Northern Hemisphere surface air temperature trends,it is important to have reliable estimates of both quantities.Sixteen different estimates of the changes in TSI since at least the 19th century were compiled from the literature.Half of these estimates are"low variability"and half are"high variability".Meanwhile,five largely-independent methods for estimating Northern Hemisphere temperature trends were evaluated using:1)only rural weather stations;2)all available stations whether urban or rural(the standard approach);3)only sea surface temperatures;4)tree-ring widths as temperature proxies;5)glacier length records as temperature proxies.The standard estimates which use urban as well as rural stations were somewhat anomalous as they implied a much greater warming in recent decades than the other estimates,suggesting that urbanization bias might still be a problem in current global temperature datasets-despite the conclusions of some earlier studies.Nonetheless,all five estimates confirm that it is currently warmer than the late 19th century,i.e.,there has been some"global warming"since the 19th century.For each of the five estimates of Northern Hemisphere temperatures,the contribution from direct solar forcing for all sixteen estimates of TSI was evaluated using simple linear least-squares fitting.The role of human activity on recent warming was then calculated by fitting the residuals to the UN IPCC’s recommended"anthropogenic forcings"time series.For all five Northern Hemisphere temperature series,different TSI estimates suggest everything from no role for the Sun in recent decades(implying that recent global warming is mostly human-caused)to most of the recent global warming being due to changes in solar activity(that is,that recent global warming is mostly natural).It appears that previous studies(including the most recent IPCC reports)which had prematurely concluded the former,had done so because they failed to adequately consider all the relevant estimates of TSI and/or to satisfactorily address the uncertainties still associated with Northern Hemisphere temperature trend estimates.Therefore,several recommendations on how the scientific community can more satisfactorily resolve these issues are provided. 展开更多
关键词 Sun:activity (Sun:)solar terrestrial relations (Sun:)sunspots Sun:faculae plages
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Effect of temperature on the leaching of heavy metals from nickel mine tailings in the arctic area,Norway
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作者 Shuai Fu Jinmei Lu +1 位作者 Ingar Walder Daishe Wu 《International Journal of Agricultural and Biological Engineering》 SCIE 2023年第2期152-158,共7页
The leaching of heavy metals from tailings deposit due to the oxidation of sulphidic tailings and formation of acidic leachate is considered a high risk to the surrounding environment.Temperature plays an important ro... The leaching of heavy metals from tailings deposit due to the oxidation of sulphidic tailings and formation of acidic leachate is considered a high risk to the surrounding environment.Temperature plays an important role in the leaching of heavy metals from tailings in changing acid-based environment,especially in the Arctic area.To investigate how the temperature variation affected metal release from tailings in the Arctic area,a series of column leaching experiments was conducted under four temperature situations(5°C,10°C,14°C and 18°C).Physicochemical properties,Fe,Zn,Ni and Mn concentrations of leachates at each cycle were measured,and multivariate statistical analysis was applied to research the effect of temperature on heavy metals leaching from tailings in the Arctic area.The results showed that higher temperatures encouraged tailings to oxidation and sulfuration of and promoted heavy metal release from the tailings through precipitation and erosion.Ni,Zn and Mn have similar releasing resources from tailings and positive correlation in the leaching activity.Rising temperature accelerated Fe leaching;Fe leaching promoted leaching of the other metals,especially of Mn.Appropriately increase temperature will accelerate oxidization and sulfidization of the tailings,promote acid generation and increase TDS and,finally,promote the release of heavy metals.Climate change,with rising temperatures increasing the risk of heavy metals leaching from the tailings,should be given greater attention.Keeping tailings away from the appropriate temperature and in a higher alkalinity is a good method to control the leaching of heavy metals from tailings. 展开更多
关键词 TAILINGS heavy metals LEACHING temperature Norway
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Effects of AGE Inhibition with Aminoguanidine in a Diabetic <i>db/db</i>Mouse Wound Model
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作者 Margrete Berdal Trond Jenssen 《Journal of Diabetes Mellitus》 2014年第2期107-114,共8页
Advanced glycation end products (AGEs) react non-enzymatically with tissue proteins to form irreversible structures involved in atherosclerosis, nephropathy, retinopathy, neuropathy, and wound healing. Studies on AGE-... Advanced glycation end products (AGEs) react non-enzymatically with tissue proteins to form irreversible structures involved in atherosclerosis, nephropathy, retinopathy, neuropathy, and wound healing. Studies on AGE-inhibitors have demonstrated possible prevention of diabetes complications. The present open label study was conducted on aminoguanidine (AGu), an inhibitor of AGE-formation, to examine potential effects on wound healing in diabetes type 2-like db/db mice during 5 - 6 weeks. The animals were divided into 4 groups: AGu from the day of wounding (day 0) topically and/or systemically in drinking water (1 g/L;group 1, n = 13);AGu 1 g/L in drinking water from 7 weeks prior to day 0 (group 2, n = 21);AGu 5 g/L in drinking water from 9 - 11 weeks prior to day 0 (group 3, n = 6);placebo controls (group 4, n = 8). Results: Glycated hemoglobin (A1C) was significantly lower in group 3 compared to the other groups (P < 0.05). Percentage change in A1C and body weight from baseline to the end of the experiment were both related to the AGu doses (1 or 5 g/L;A1C-change, P = 0.01;weight-change, P = 0.04, both for linear trend across groups 4, 2, and 3, respectively). Even so, percentage wound closure was not improved in the AGu-treated groups compared to controls (P ≥ 0.8). 展开更多
关键词 Diabetes WOUND Glycation INHIBITION Animals
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Birth Weight in Relation to Maternal Blood Levels of Selected Elements in Slovenian Populations: A Cross-sectional Study
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作者 Marta Jagodic Janja Snoj Tratnik +7 位作者 Darja Mazej Anja Stajnko Majda Pavlin Mladen Krsnik Alfred B. Kobal Lijana Kononenko Jon Oyvind Odl Milena Horvat 《Journal of Health Science》 2017年第2期95-106,共12页
The objective of the present study was to evaluate the relation between maternal blood levels of selected toxic and potentially toxic elements (manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium ... The objective of the present study was to evaluate the relation between maternal blood levels of selected toxic and potentially toxic elements (manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), lead (Pb) and mercury (Hg)) and birth weight of their new-borns in a Slovenian population, taking into account maternal socio-demographic characteristics and dietary habits. 535 women from 12 regions of Slovenia were recruited at delivery. Maternal blood was collected at 1.5 months after birth. Associations between birth weight and a) predictors obtained through the questionnaires and b) levels of selected elements were tested using bivariate tests and multiple linear regression. Multiple regression models revealed maternal age as an additional predictor for birth weight and confirmed pre-pregnancy body mass, estimated gestational age and gender of the baby as the main predictors for birth weight. Mn in maternal blood was significantly and positively associated with birth weight. The positive association observed between birth weight and Mn in maternal blood could be explained by the essentiality of Mn in foetal development as an important cofactor in enzymereactions in bone formation and in metabolic regulation for amino acid, lipid, protein and carbohydrate levels. 展开更多
关键词 Birth weight toxic elements essential elements maternal whole blood oreventive health Slovenia.
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Changes in Barents Sea Ice Edge Positions in the Last 442 Years. Part 2: Sun, Moon and Planets
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作者 Jan-Erik Solheim Stig Falk-Petersen +2 位作者 Ole Humlum Nils-Axel Mö rner 《International Journal of Astronomy and Astrophysics》 2021年第2期279-341,共63页
This is the second paper in a series of two, which analyze the position of the Barents Sea ice-edge (BIE) based on a 442-year long dataset to understand its time variations. The data have been collected from ship-logs... This is the second paper in a series of two, which analyze the position of the Barents Sea ice-edge (BIE) based on a 442-year long dataset to understand its time variations. The data have been collected from ship-logs, polar expeditions, and hunters in addition to airplanes and satellites in recent times. Our main result is that the BIE position alternates between a southern and a northern position followed by Gulf Stream Beats (GSBs) at the occurrence of deep solar minima. We decompose the low frequency BIE position variations in cycles composed of dominant periods which are related to the Jose period of 179 years, indicating planetary forcings. We propose that the mechanism transferring planetary signals into changes in BIE position is the solar wind (SW), which provides magnetic shielding of the Earth in addition to geomagnetic disturbances. Increase in the solar wind produces pressure which decelerates the Earth’s rotation. It also transfers electrical energy to the ring current in the earth’s magnetosphere. This current magnetizes the earth’s solid core and makes it rotate faster. To conserve angular momentum the earth’s outer fluid mantle rotates slower with a delay of about 100 years. In addition will geomagnetic storms, initiated by solar coronal mass ejections (CMEs) penetrate deep in the Earth’s atmosphere and change pressure pattern in the Arctic. This effect is larger during solar minima since the magnetic shielding then is reduced. The Arctic may then experience local warming. The transition of solar activities to a possibly deep and long minimum in the present century may indicate Arctic cooling and the BIE moving south this century. For the North Atlantic region, effects of the BIE expanding southward will have noticeable consequences for the ocean bio-production from about 2040. 展开更多
关键词 Barents Sea Ice Edge Position Cyclic and Non-Linear Changes Lunar and Solar Forcing Planetary Orbit Synchronization
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Does soak time influence the effect of artificial light on catch efficiency in snow crab(Chionoecetes opilio)pot fishery?
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作者 Kristine Cerbule Bent Herrmann +2 位作者 Eduardo Grimaldo Leif Grimsmo Junita D.Karlsen 《Aquaculture and Fisheries》 2025年第2期330-343,共14页
In the Barents Sea commercial snow crab(Chionoecetes opilio)fishery,an increase in catch efficiency of the conical pots is important for the profitability of the industry.Light emitting diodes(LEDs)have previously bee... In the Barents Sea commercial snow crab(Chionoecetes opilio)fishery,an increase in catch efficiency of the conical pots is important for the profitability of the industry.Light emitting diodes(LEDs)have previously been tested for increasing catch efficiency of the snow crab pots.These earlier experiments have shown varying results ranging from large increase in snow crab catches to no significant effect.These experiments have used different pot soaking times;however,the soaking time might affect the impact of LEDs on catch efficiency.In commercial snow crab fishery,the pot soak time is varying which has not been considered in earlier experiments testing the effect of LEDs.Therefore,this study examined whether pot soaking time can explain the observed differences in relative catch efficiency of snow crab pots with and without LEDs with soak times ranging from 2 to 14 days in the Barents Sea snow crab fishery.For target sizes of snow crab(≥95 mm carapace width),results indicated an increase in catch efficiency between 10 and 30%for pots with LEDs with exception of one experiment using six days soak time.However,experimental results were subjected to large uncertainties and,except from one experiment with five days soak time,the estimated increases were nonsignificant.Furthermore,the pot soak time was not found to impact the effect of white LEDs on capture efficiency. 展开更多
关键词 Snow crab Catch efficiency Soak time LED Pot fishery
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Photo-responsive polypropylene/zinc oxide/polydopamine-TEMPO composite membranes with light-induced self-sterilization
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作者 Huajie Wang Hao Peng +6 位作者 Wenhao Ji Jiaxin Wang Xiaoyan Du Wen Song Wen Zhang Fazli Wahid Ali Raza 《Nano Materials Science》 2025年第2期276-288,共13页
Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-... Face masks play a pivotal role in preventing infection transmission.However,the capture of infection-sourced particles in face masks poses challenges related to reuse,necessitating proper disposal.We developed a self-sterilizable polypropylene-based membrane for face masks to address challenges associated with infection transmission prevention.The membrane,created using 3D printing,underwent functionalization with zinc oxide(ZnO)and polydopamine(PDA)-TEMPO to achieve broad-spectrum light absorption and facilitate self-sterilization through photocatalytic and photothermal effects upon light exposure.The hydrophobic surface(water contact angle:133±2°)minimized moisture accumulation,and the membrane exhibited robust mechanical properties,including shear strength(1.25±0.5kPa)and peel resistance strength(112.8±11.2kPa).The evaluation demonstrated stability in airflow(0-500cm^(3)/s)and excellent aerosol filtration efficiency(94.8±0.6%)for particles(PM 0.3,PM 2.5,PM 10),comparable to commercial masks.The membrane showed antibacterial efficacy over five uses in a simulated respiratory environment.Safety assessments confirmed biocompatibility through cytocompatibility and skin irritation assays.In conclusion,this membrane offers efficient filtration and photo-triggered sterilization,presenting a promising solution for next-generation face masks to address concerns related to reuse,disposal,and infection control. 展开更多
关键词 Face masks 3D printing Nanocomposites POLYDOPAMINE PHOTO-RESPONSIVE Self-sterilization
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