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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Long-Term Trends in Pre-Summer Daytime and Nocturnal Extreme Hourly Rainfall in a Coastal City of South China
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作者 苏琳 李俊鲁 +1 位作者 黄伟健 冯志雄 《Journal of Tropical Meteorology》 SCIE 2023年第1期39-54,共16页
The long-term trends in the occurrence frequency of pre-summer daytime and nocturnal extreme hourly rainfall(EXHR) during 1988-2018 in Hong Kong and their spatial distributions are examined and analyzed. Despite a sig... The long-term trends in the occurrence frequency of pre-summer daytime and nocturnal extreme hourly rainfall(EXHR) during 1988-2018 in Hong Kong and their spatial distributions are examined and analyzed. Despite a significant increasing trend observed in the occurrence frequency of pre-summer EXHRs during the investigated period,the increase in daytime and nocturnal EXHRs show distinct spatial patterns. Nocturnal EXHRs show uniform increasing trends over the entire Hong Kong. However, the increase in daytime EXHRs is concentrated over the northern or eastern areas of Hong Kong, indicating a downstream shift of pre-summer EXHRs in Hong Kong with regard to the prevailing southwesterly monsoonal flows in south China. The clustering of weather types associated with daytime and nocturnal EXHRs further reveals that the increase in EXHRs over Hong Kong are mainly contributed by the increase of the events associated with southwesterly monsoonal flows with relatively high speeds. During the past few decades, the southwesterly monsoonal flows at coastal south China have undergone a substantial weakening due to the increased surface roughness induced by the urbanization over the Guangdong-Hong Kong-Macao Greater Bay Area since 1990s,leading to enhanced low-level convergence and thus significant increase in EXHRs at coastal south China. Meanwhile,daytime sea-wind circulation at coastal south China is markedly enhanced during the investigated period, which is the main reason for the northward shift of daytime EXHRs in Hong Kong. In addition, the blocked southwesterly monsoonal flows at coastal south China are detoured eastward, leading to stronger convergence and increase in EXHRs at eastern coast of Hong Kong, especially during daytime, when the easterly sea winds prevail at the region. 展开更多
关键词 extreme hourly rainfall diurnal rainfall cycle linear trend coastal Pearl River Delta
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Long-Term Trends in Photosynthetically Active Radiation in Beijing 被引量:1
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作者 胡波 王跃思 刘广仁 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2010年第6期1380-1388,共9页
A long-term dataset of photosynthetically active radiation (Qp) is reconstructed from a broadband global solar radiation (Rs) dataset through an all-weather reconstruction model. This method is based on four years... A long-term dataset of photosynthetically active radiation (Qp) is reconstructed from a broadband global solar radiation (Rs) dataset through an all-weather reconstruction model. This method is based on four years' worth of data collected in Beijing. Observation data of Rs and Qp from 2005-2008 are used to investigate the temporal variability of Qp and its dependence on the clearness index and solar zenith angle. A simple and effcient all-weather empirically derived reconstruction model is proposed to reconstruct Qp from Rs. This reconstruction method is found to estimate instantaneous Qp with high accuracy. The annual mean of the daily values of Qp during the period 1958-2005 period is 25.06 mol m-2 d-1. The magnitude of the long-term trend for the annual averaged Qp is presented (-0.19 mol m-2 yr-1 from 1958-1997 and -0.12 mol m-2 yr-1 from 1958-2005). The trend in Qp exhibits sharp decreases in the spring and summer and more gentle decreases in the autumn and winter. 展开更多
关键词 photosynthetically active radiation historical data reconstruction long-term trends
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Long-Term Trends in the Probability of Different Grades of Haze Days in China from 1960 to 2013 被引量:1
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作者 FU Chuan-bo DAN Li 《Journal of Tropical Meteorology》 SCIE 2020年第2期199-207,共9页
The number of haze days and daily visibility data for 543 stations in China were used to define the probabilities of four grades of haze days:slight haze(SLH)days;light haze(LIH)days;moderate haze(MOH)days;and severe ... The number of haze days and daily visibility data for 543 stations in China were used to define the probabilities of four grades of haze days:slight haze(SLH)days;light haze(LIH)days;moderate haze(MOH)days;and severe haze(SEH)days.The change trends of the four grades of haze were investigated and the following results were obtained.The highest probability was obtained for SLH days(95.138%),which showed a decreasing trend over the last54 years with the fastest rate of decrease of-0.903%·(10 years)-1 and a trend coefficient of-0.699,passing the 99.9%confidence level.The probabilities of LIH and MOH days increased steadily,whereas the probability of SEH days showed a slight downward trend during that period.The increasing probability of SLH days was mainly distributed to the east of 105°E and the south of 42°N and the highest value of the trend coefficient was located in the Pearl River Delta and Yangtze River Delta regions.The increasing probability of LIH days was mainly distributed in eastern China and the southeastern coastal region.The probabilities of MOH and SEH days was similar to the probability of LIH days.An analysis of the four grades of haze days in cities with different sizes suggested that the probability of SLH days in large cities and medium cities clearly decreased during the last 54 years.However,the probabilities of LIH days was<10%and increased steadily.The probability of MOH days showed a clear interdecadal fluctuation and the probability of SEH days showed a weak upward trend.The probability of SLH days in small cities within 0.8°of large or medium cities decreased steadily,but the probability of LIH and MOH days clearly increased,which might be attributed to the impact of large and medium cities.The probability of SLH days in small cities>1.5°from a large or medium city showed an increasing trend and reached 100%after 1990;the probability of the other three grades was small and decreased significantly. 展开更多
关键词 haze days long-term trends PROBABILITY VISIBILITY China
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Long-Term Trends and Its Best Functional Form Estimation of Yearly Maximum and Minimum Temperatures at Cotonou City by Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise Method
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作者 Médard Noukpo Agbazo Joseph Adébiyi Adéchinan +1 位作者 Gabin Koto N’gobi Joseph Bessou 《Atmospheric and Climate Sciences》 2022年第1期31-42,共12页
The understanding of the long-term trend in climatic variables is necessary for the climate change impacts studies and for modeling several processes in environmental engineering. However, for climatic variables, long... The understanding of the long-term trend in climatic variables is necessary for the climate change impacts studies and for modeling several processes in environmental engineering. However, for climatic variables, long-term trend is usually unknown whether there is a trend component and, if so, the functional form of this trend is also unknown. In this context, a conventional strategy consists to assume randomly the shape of the local trends in the time series. For example, the polynomial forms with random order are arbitrarily chosen as the shape of the trend without any previous justification. This study aims to <span style="font-family:Verdana;">1</span><span style="font-family:;" "=""><span style="font-family:Verdana;">) estimate the real long-term nonlinear trend and the changing rate of </span><span style="font-family:Verdana;">the yearly high temperature among the daily minimum (YHTaDMinT) and maximum temperatures (YHTaDMaxT) observed at Cotonou city, </span></span><span style="font-family:Verdana;">2</span><span style="font-family:Verdana;">) find out for these real trend and trend increment, the best polynomial trend model among four trend models (linear, quadratic, third-order and fourth-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">order polynomial function). For both time series, the results show that YHTaDMinT and YHTaDMaxT time series are characterized by nonlinear and </span><span style="font-family:Verdana;">monotonically increasing trend. The trend increments present differen</span><span style="font-family:Verdana;">t phases in their nonmonotone variations. Among the four trend estimations models, the trend obtained by third-order and fourth-order polynomial functions exhibits a close pattern with the real long-term nonlinear trend given by the Improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (ICEEMDAN). But, the fourth-order polynomial function is optimal, therefore, it can be used as the functional form of trend. In the trend increment case, for the YHTaDMaxT time series, the fourth-order fit is systematically the best among the four proposed trend models. Whereas for the YHTaDMinT time series, the third-order and fourth-order polynomial functions present the same performance. They can both be used as the functional </span><span style="font-family:Verdana;">form of trend increments. Overall, the fourth-order polynomial function presents</span><span style="font-family:Verdana;"> a good performance in terms of trend and trend increments estimation.</span></span> 展开更多
关键词 long-term trends Polynomial trend Models trend Increment ICEEMDAN Extrema Temperature
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Long-Term Trends in Extreme Temperatures in Hong Kong and Southern China 被引量:3
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作者 T.C.LEE E.W.L.GINN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第1期147-157,共11页
The observed long-term trends in extreme temperatures in Hong Kong were studied based on the meteorological data recorded at the Hong Kong Observatory Headquarters from 1885-2008. Results show that, over the past 124 ... The observed long-term trends in extreme temperatures in Hong Kong were studied based on the meteorological data recorded at the Hong Kong Observatory Headquarters from 1885-2008. Results show that, over the past 124 years, the extreme daily minimum and maximum temperatures, as well as the length of the warm spell in Hong Kong, exhibit statistically significant long-term rising trends, while the length of the cold spell shows a statistically significant decreasing trend. The time-dependent return period analysis also indicated that the return period for daily minimum temperature at 4°C or lower lengthened considerably from 6 years in 1900 to over 150 years in 2000, while the return periods for daily maximum temperature reaching 35°C or above shortened drastically from 32 years in 1900 to 4.5 years in 2000. Past trends in extreme temperatures from selected weather stations in southern China from 1951-2004 were also assessed. Over 70% of the stations studied yielded a statistically significant rising trend in extreme daily minimum temperature, while the trend for extreme maximum temperatures was found to vary, with no significant trend established for the majority of stations. 展开更多
关键词 extreme temperature long-term trend Hong Kong southern China
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CLIMATE CHANGE:LONG-TERM TRENDS AND SHORT-TERM OSCILLATIONS 被引量:1
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作者 高新全 张欣 钱维宏 《Journal of Tropical Meteorology》 SCIE 2006年第2期139-149,共11页
Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for the past 1000 years shows that climate change in the last millennium includes long-term trends and varioas oscillations. ... Identifying the Northern Hemisphere (NH) temperature reconstruction and instrumental data for the past 1000 years shows that climate change in the last millennium includes long-term trends and varioas oscillations. Two long-term trends and the quasi-70-year oscillation were detected in the global temperature series tbr the last 140 years and the NH millennium series. One important feature was emphasized that temperature decreases slowly but it increases rapidly based on the analysis of different series. Benefits can be obtained of climate change from understanding various long-term trends and oscillations. Millennial temperature proxies from the natural climate system and time series of nonlinear model system are used in understanding the natural climate change and recognizing potential benefits by using the method of wavelet transform analysis. The results from numerical modeling show that major oscillations contained in numerical solutions on the interdecadal timescale are consistent with that of natural proxies. It seems that these oscillations in the climate change are not directly linked with the solar radiation as an external tbrcing. This investigation may conclude that the climate variability at the interdecadal timescale strongly depends on the internal nonlinear effects in the climate system. 展开更多
关键词 climate change trend and oscillation natural climate system nonlinear model system
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Long-Term Trends in Near-Surface Wind Speed over the Southern Hemisphere: A Preliminary Analysis 被引量:1
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作者 Luiz Felipe N. Cardoso Wanderson Luiz Silva Maria G. A. Justi da Silva 《International Journal of Geosciences》 2016年第7期938-943,共6页
Many studies that discuss observed trends in wind speed focus primarily on regions of the Northern Hemisphere, so there is little research directed to the Southern Hemisphere. This paper pre- sents a preliminary inves... Many studies that discuss observed trends in wind speed focus primarily on regions of the Northern Hemisphere, so there is little research directed to the Southern Hemisphere. This paper pre- sents a preliminary investigation of possible statistically significant trends in wind speed over the Southern Hemisphere, with a detailing on the South American continent, between 1961 and 2008. Thus, data from the 20th Century Reanalysis V2 were examined with statistical tests of Mann- Kendall and Sen’s Bend in order to establish the significance and the magnitude of detected trends. The previous results indicate statistically significant trends of increase in average wind speedover the equatorial region of the planet, as well as in the eastern sector of the South Pacific and South Atlantic Oceans. In South America, the most significant trends of decrease in wind speed were noted in some areas of the southern sector of the continent, even as in the adjacent Atlantic Ocean to Argentina. Further studies should be performed to physically support the occurrence of these trends in wind speed. In addition, other observed and reanalysis data sets should be explored to update and corroborate these primary analyzes. 展开更多
关键词 Climate Change MANN-KENDALL REANALYSIS Southern Hemisphere trends Wind Speed
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Long-Term Trends of Carbon Monoxide Total Columnar Amount in Urban Areas and Background Regions:Ground-and Satellite-based Spectroscopic Measurements
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作者 Pucai WANG N.F.ELANSKY +11 位作者 Yu.M.TIMOFEEV Gengchen WANG G.S.GOLITSYN M.V.MAKAROVA V.S.RAKITIN Yu.SHTABKIN A.I.SKOROKHOD E.I.GRECHKO E.V.FOKEEVA A.N.SAFRONOV Liang RAN Ting WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第7期785-795,共11页
A comparative study was carried out to explore carbon monoxide total columnar amount(CO TC) in background and polluted atmosphere, including the stations of ZSS(Zvenigorod), ZOTTO(Central Siberia), Peterhof, Bei... A comparative study was carried out to explore carbon monoxide total columnar amount(CO TC) in background and polluted atmosphere, including the stations of ZSS(Zvenigorod), ZOTTO(Central Siberia), Peterhof, Beijing, and Moscow,during 1998–2014, on the basis of ground-and satellite-based spectroscopic measurements. Interannual variations of CO TC in different regions of Eurasia were obtained from ground-based spectroscopic observations, combined with satellite data from the sensors MOPITT(2001–14), AIRS(2003–14), and IASI Met Op-A(2010–13). A decreasing trend in CO TC(1998–2014) was found at the urban site of Beijing, where CO TC decreased by 1.14% ± 0.87% yr^(-1). Meanwhile, at the Moscow site, CO TC decreased remarkably by 3.73% ± 0.39% yr^(-1). In the background regions(ZSS, ZOTTO, Peterhof), the reduction was 0.9%–1.7% yr^(-1) during the same period. Based on the AIRSv6 satellite data for the period 2003–14, a slight decrease(0.4%–0.6% yr^(-1)) of CO TC was detected over the midlatitudes of Eurasia, while a reduction of 0.9%–1.2% yr^(-1) was found in Southeast Asia. The degree of correlation between the CO TC derived from satellite products(MOPITTv6 Joint, AIRSv6 and IASI Met Op-A) and ground-based measurements was calculated, revealing significant correlation in unpolluted regions.While in polluted areas, IASI Met Op-A and AIRSv6 data underestimated CO TC by a factor of 1.5–2.8. On average, the correlation coefficient between ground-and satellite-based data increased significantly for cases with PBL heights greater than 500 m. 展开更多
关键词 carbon monoxide trend spectroscopic measurement MOPITT AIRS IASI
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从Google Trends看“一带一路”倡议的国际反响
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作者 汤宏波 李富山 +1 位作者 赵素婷 吕新华 《情报探索》 2024年第5期122-127,共6页
[目的/意义]2013年中国提出“一带一路”倡议,这对推动我国继续繁荣发展并为全球提供中国治理体系方案等具有重大意义。[方法/过程]利用Google Trends,分析中国“一带一路”倡议的国际反响及其潜在阻碍因子。[结果/结论]“一带一路”倡... [目的/意义]2013年中国提出“一带一路”倡议,这对推动我国继续繁荣发展并为全球提供中国治理体系方案等具有重大意义。[方法/过程]利用Google Trends,分析中国“一带一路”倡议的国际反响及其潜在阻碍因子。[结果/结论]“一带一路”倡议受到国际上绝大多数国家民众的支持和关注;个别国家为了压制中国的国际影响力,通过“债务陷阱外交”“珍珠链战略”以及环境问题等方面抹黑“一带一路”,行动上提出“重建更好世界”等企图替代中国的“一带一路”倡议。得益于“一带一路”倡议投资没有附加条件以及G7国家内部自身问题,“一带一路”倡议仍然获得了广大第三世界国家的支持,并将继续是推动世界经济发展的重要力量。 展开更多
关键词 “一带一路”倡议 国际反响 Google trends
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Human brain organoid:trends,evolution,and remaining challenges 被引量:1
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作者 Minghui Li Yuhan Yuan +3 位作者 Zongkun Hou Shilei Hao Liang Jin Bochu Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2387-2399,共13页
Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and a... Advanced brain organoids provide promising platforms for deciphering the cellular and molecular processes of human neural development and diseases.Although various studies and reviews have described developments and advancements in brain organoids,few studies have comprehensively summarized and analyzed the global trends in this area of neuroscience.To identify and further facilitate the development of cerebral organoids,we utilized bibliometrics and visualization methods to analyze the global trends and evolution of brain organoids in the last 10 years.First,annual publications,countries/regions,organizations,journals,authors,co-citations,and keywords relating to brain organoids were identified.The hotspots in this field were also systematically identified.Subsequently,current applications for brain organoids in neuroscience,including human neural development,neural disorders,infectious diseases,regenerative medicine,drug discovery,and toxicity assessment studies,are comprehensively discussed.Towards that end,several considerations regarding the current challenges in brain organoid research and future strategies to advance neuroscience will be presented to further promote their application in neurological research. 展开更多
关键词 bibliometric analysis brain organoids cerebral organoids global trends NEUROSCIENCE
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Long-term ocean temperature trend and marine heatwaves
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作者 Min ZHANG Yangyan CHENG +4 位作者 Gang WANG Qi SHU Chang ZHAO Yuanling ZHANG Fangli QIAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1037-1047,共11页
Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and livelihoods.Appropriate MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongl... Marine heatwaves(MHWs)can cause irreversible damage to marine ecosystems and livelihoods.Appropriate MHW characterization remains difficult,because the choice of a sea surface temperature(SST)temporal baseline strongly influences MHW identification.Following a recent work suggesting that there should be a communicating baseline for long-term ocean temperature trends(LTT)and MHWs,we provided an effective and quantitative solution to calculate LTT and MHWs simultaneously by using the ensemble empirical mode decomposition(EEMD)method.The long-term nonlinear trend of SST obtained by EEMD shows superiority over the traditional linear trend in that the data extension does not alter prior results.The MHWs identified from the detrended SST data exhibited low sensitivity to the baseline choice,demonstrating the robustness of our method.We also derived the total heat exposure(THE)by combining LTT and MHWs.The THE was sensitive to the fixed-period baseline choice,with a response to increasing SST that depended on the onset time of a perpetual MHW state(identified MHW days equal to the year length).Subtropical areas,the Indian Ocean,and part of the Southern Ocean were most sensitive to the long-term global warming trend. 展开更多
关键词 marine heatwaves(MHWs) ensemble empirical mode decomposition(EEMD) long-term temperature(LTT)trend total heat exposure(THE)
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Analysis of Temperature Trends and Variations in the Arabian Peninsula’s Upper Atmosphere
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作者 Abdullrahman H. Maghrabi 《Atmospheric and Climate Sciences》 2024年第1期85-100,共16页
In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the A... In this study, the trends of upper-air temperatures are analysed by utilising radiosonde observations for the barometric levels at 700, 500, 300, 200, 150, 100 and 50 hPa from five meteorological stations within the Arabian Peninsula from January 1986 to August 2015. The mean monthly variations of the temperatures at these levels are characterised and established. The magnitudes of the annual trends of the mean temperatures for each site for the selected barometric levels are studied and statistically tested using Mann-Kendall rank statistics at different significance levels. The temperature trends at different pressure levels show that the upper troposphere and lower stratosphere are warming, while the middle troposphere is cooling which is consistent with the findings of other studies. The variations in upper air temperature observed in this study can be attributed to a range of factors, including increasing greenhouse gas concentrations, changes in atmospheric circulation patterns, variations in solar activity, aerosols and volcanic eruptions, and land use and land cover change. 展开更多
关键词 Upper-Air Temperature Variability long-term trend Arabian Peninsula Climate Change Mann-Kendell
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Effects of temperature and precipitation on drought trends in Xinjiang, China
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作者 YANG Jianhua LI Yaqian +3 位作者 ZHOU Lei ZHANG Zhenqing ZHOU Hongkui WU Jianjun 《Journal of Arid Land》 SCIE CSCD 2024年第8期1098-1117,共20页
The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and pre... The characteristics of drought in Xinjiang Uygur Autonomous Region(Xinjiang),China have changed due to changes in the spatiotemporal patterns of temperature and precipitation,however,the effects of temperature and precipitation—the two most important factors influencing drought—have not yet been thoroughly explored in this region.In this study,we first calculated the standard precipitation evapotranspiration index(SPEI)in Xinjiang from 1980 to 2020 based on the monthly precipitation and monthly average temperature.Then the spatiotemporal characteristics of temperature,precipitation,and drought in Xinjiang from 1980 to 2020 were analyzed using the Theil-Sen median trend analysis method and Mann-Kendall test.A series of SPEI-based scenario-setting experiments by combining the observed and detrended climatic factors were utilized to quantify the effects of individual climatic factor(i.e.,temperature and precipitation).The results revealed that both temperature and precipitation had experienced increasing trends at most meteorological stations in Xinjiang from 1980 to 2020,especially the spring temperature and winter precipitation.Due to the influence of temperature,trends of intensifying drought have been observed at spring,summer,autumn,and annual scales.In addition,the drought trends in southern Xinjiang were more notable than those in northern Xinjiang.From 1980 to 2020,temperature trends exacerbated drought trends,but precipitation trends alleviated drought trends in Xinjiang.Most meteorological stations in Xinjiang exhibited temperature-dominated drought trend except in winter;in winter,most stations exhibited precipitation-dominated wetting trend.The findings of this study highlight the importance of the impact of temperature on drought in Xinjiang and deepen the understanding of the factors influencing drought. 展开更多
关键词 standardized precipitation evapotranspiration index(SPEI) climate change drought characteristics trend analysis arid area temperature trend contribution analysis
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Bibliometric analysis of hotspots and trends of global myopia research
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作者 Xing-Yang Wu Hui-Hui Fang +3 位作者 Yan-Wu Xu Yan-Ling Zhang Shao-Chong Zhang Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期940-950,共11页
AIM:To gain insights into the global research hotspots and trends of myopia.METHODS:Articles were downloaded from January 1,2013 to December 31,2022 from the Science Core Database website and were mainly statistically... AIM:To gain insights into the global research hotspots and trends of myopia.METHODS:Articles were downloaded from January 1,2013 to December 31,2022 from the Science Core Database website and were mainly statistically analyzed by bibliometrics software.RESULTS:A total of 444 institutions in 87 countries published 4124 articles.Between 2013 and 2022,China had the highest number of publications(n=1865)and the highest H-index(61).Sun Yat-sen University had the highest number of publications(n=229)and the highest H-index(33).Ophthalmology is the main category in related journals.Citations from 2020 to 2022 highlight keywords of options and reference,child health(pediatrics),myopic traction mechanism,public health,and machine learning,which represent research frontiers.CONCLUSION:Myopia has become a hot research field.China and Chinese institutions have the strongest academic influence in the field from 2013 to 2022.The main driver of myopic research is still medical or ophthalmologists.This study highlights the importance of public health in addressing the global rise in myopia,especially its impact on children’s health.At present,a unified theoretical system is still needed.Accurate surgical and therapeutic solutions must be proposed for people with different characteristics to manage and intervene refractive errors.In addition,the benefits of artificial intelligence(AI)models are also reflected in disease monitoring and prediction. 展开更多
关键词 bibliometric analysis MYOPIA global trends
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Data-enhanced revealing of trends in Geoscience
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作者 Yu Zhao Meng Wang +6 位作者 Jiaxin Ding Jiexing Qi Lyuwen Wu Sibo Zhang Luoyi Fu Xinbing Wang Li Cheng 《Journal of Data and Information Science》 CSCD 2024年第3期29-43,共15页
Purpose:This article presents an in-depth analysis of global research trends in Geosciences from 2014 to 2023.By integrating bibliometric analysis with expert insights from the Deep-time Digital Earth(DDE)initiative,t... Purpose:This article presents an in-depth analysis of global research trends in Geosciences from 2014 to 2023.By integrating bibliometric analysis with expert insights from the Deep-time Digital Earth(DDE)initiative,this article identifies key emerging themes shaping the landscape of Earth Sciences①.Design/methodology/approach:The identification process involved a meticulous analysis of over 400,000 papers from 466 Geosciences journals and approximately 5,800 papers from 93 interdisciplinary journals sourced from the Web of Science and Dimensions database.To map relationships between articles,citation networks were constructed,and spectral clustering algorithms were then employed to identify groups of related research,resulting in 407 clusters.Relevant research terms were extracted using the Log-Likelihood Ratio(LLR)algorithm,followed by statistical analyses on the volume of papers,average publication year,and average citation count within each cluster.Additionally,expert knowledge from DDE Scientific Committee was utilized to select top 30 trends based on their representation,relevance,and impact within Geosciences,and finalize naming of these top trends with consideration of the content and implications of the associated research.This comprehensive approach in systematically delineating and characterizing the trends in a way which is understandable to geoscientists.Findings:Thirty significant trends were identified in the field of Geosciences,spanning five domains:deep space,deep time,deep Earth,habitable Earth,and big data.These topics reflect the latest trends and advancements in Geosciences and have the potential to address real-world problems that are closely related to society,science,and technology.Research limitations:The analyzed data of this study only contain those were included in the Web of Science.Practical implications:This study will strongly support the organizations and individual scientists to understand the modern frontier of earth science,especially on solid earth.The organizations such as the surveys or natural science fund could map out areas for future exploration and analyze the hot topics reference to this study.Originality/value:This paper integrates bibliometric analysis with expert insights to highlight the most significant trends on earth science and reach the individual scientist and public by global voting. 展开更多
关键词 GEOSCIENCES Research trends BIBLIOMETRICS Expert knowledge Global voting
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Time trends and outcomes of gastrostomy placement in a Swedish national cohort over two decades
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作者 Martin Löfling Skogar Magnus Sundbom 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1358-1367,共10页
BACKGROUND Percutaneous endoscopic gastrostomy(PEG)and laparoscopically inserted gastrostomy have become the gold standard for adult patients and children,respectively,requiring long-term enteral nutrition support.Pro... BACKGROUND Percutaneous endoscopic gastrostomy(PEG)and laparoscopically inserted gastrostomy have become the gold standard for adult patients and children,respectively,requiring long-term enteral nutrition support.Procedure-related mortality is a rare event,often reported to be zero in smaller studies.National data on 30-d mortality and long-term survival rates after gastrostomy placement are scarce in the literature.AIM To study the use of gastrostomies in Sweden from 1998-2019 and to analyze procedure-related mortality and short-term(<30 d)and long-term survival.METHODS In this retrospective,population-based cohort study,individuals that had received a gastrostomy between 1998-2019 in Sweden were included.Individuals were identified in the Swedish National Patient Register,and survival analysis was possible by cross-referencing the Swedish Death Register.The cohort was divided into three age groups:Children(0-18 years);adults(19-64 years);and elderly(≥65 years).Kaplan-Meier with log-rank test and Cox regression were used for survival analysis.RESULTS In total 48682 individuals(52%males,average age 60.9±25.3 years)were identified.The cohort consisted of 12.0%children,29.5%adults,and 58.5%elderly.An increased use of gastrostomies was observed during the study period,from 13.7/100000 to 22.3/100000 individuals(P<0.001).The use of PEG more than doubled(about 800 to 1800/year),with a corresponding decrease in open gastrostomy(about 700 to 340/year).Laparoscopic gastrostomy increased more than ten-fold(about 20 to 240/year).Overall,PEG,open gastrostomy,and laparoscopic gastrostomy constituted 70.0%(n=34060),23.3%(n=11336),and 4.9%(n=2404),respectively.Procedure-related mortality was 0.1%(n=44)overall(PEG:0.05%,open:0.24%,laparoscopic:0.04%).The overall 30-d mortality rate was 10.0%(PEG:9.8%,open:12.4%,laparoscopic:1.7%)and decreased from 11.6%in 1998-2009 vs 8.5%in 2010-2019(P<0.001).One-year and ten-year survival rates for children,adults,and elderly were 93.7%,67.5%,and 42.1%and 79.9%,39.2%,and 6.8%,respectively.The most common causes of death were malignancies and cardiovascular and respiratory diseases.CONCLUSION The annual use of gastrostomies in Sweden increased during the study period,with a shift towards more minimally invasive procedures.Although procedure-related death was rare,the overall 30-d mortality rate was high(10%).To overcome this,we believe that patient selection should be improved. 展开更多
关键词 GASTROSTOMY Percutaneous endoscopic gastrostomy DYSPHAGIA Enteral nutrition long-term Survival COMPLICATION
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Phoenix Species in Asia:A Systematic Review on Research Trends,Status,Distribution,Ethnobotany and Pharmacological Activities
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作者 Santosh AYER Amrita BHUSAL +1 位作者 Pratima CHHETRI Anuska SUBEDI 《Journal of Resources and Ecology》 CSCD 2024年第5期1382-1392,共11页
Phoenix species,recognized for their profound ecological,economic,and cultural significance,have garnered substantial attention in research across Asia.However,limited studies exist on research trends,status,distribut... Phoenix species,recognized for their profound ecological,economic,and cultural significance,have garnered substantial attention in research across Asia.However,limited studies exist on research trends,status,distribution,ethnobotany,and pharmacological activities of Phoenix species in the region.The objective of this study is to compile pertinent information on these aspects for Phoenix species in Asia.We employed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)approach to systematically examine the literature pertaining to Phoenix species in the Asian region.This comprehensive review analyzes research trends on Phoenix species in Asia from year 2000 to 2023.A total of 42 studies were identified,showcasing a growing interest,with a notable peak in publications in 2019.The temporal distribution suggests fluctuating attention over the years.Geographically,the concentration of studies is limited to 12 out of 48 Asian countries,emphasizing the need for more extensive exploration given the widespread availability of Phoenix species.The research primarily focuses on pharmacology,followed by ethnobotany,morphology,taxonomy,material science,environmental engineering,and ecology.Notably,studies disproportionately concentrate on Phoenix dactylifera,leaving other species underexplored.The analysis of research focus,species distribution,and geographical representation underscores the importance of diversifying research themes and exploring the ecological,economic,and cultural significance of lesser-studied Phoenix species across Asia.The findings highlight both the growing interest and existing gaps in our knowledge,urging for a more comprehensive exploration of the entire genus to unravel its full potential and significance across Asian landscapes. 展开更多
关键词 Phoenix species research trend ETHNOBOTANY multipurpose plant ASIA
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Global Scientific Trends in Research Related to Diabetic Sarcopenia from 1993 to 2023: A Bibliometric Analysis
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作者 Qing Yang Yuan Zhao +2 位作者 Han Lu Yaolei Cha Lijie Yang 《Journal of Biosciences and Medicines》 2024年第3期204-222,共19页
Objectives: In this study, bibliometric approach was used to explore the literature in the field of research related to Diabetic Myasthenia Gravis in order to identify the current research progress in Diabetic Myasthe... Objectives: In this study, bibliometric approach was used to explore the literature in the field of research related to Diabetic Myasthenia Gravis in order to identify the current research progress in Diabetic Myasthenia Gravis related research and to help the researchers to predict the future hotspots in the field of research and to provide reference for the research. Methods: Literature related to diabetic sarcopenia published from 1993 to 2023 since the inception of the repository was extracted from the Web of Science Core Collection (WoSCC) and bibliometric analyses were performed. We have analysed the published literature of the last approximately almost 30 years, as well as publication and citation analyses from different countries, institutions, journals and authors. For keywords, we performed co-occurrence, clustering, timeline view and citation burst analysis. Results: On the basis of 1564 publications, we found a continuous increase in the number of publications and citations, especially in the last six years. The United States is the most representative country, and Seoul National University (SNU) is the most representative institution. The most popular journal in the field is Diabetes Care;Fukui, Michiaki is the most prolific author, leading many studies related to diabetic sarcopenia. The most frequently cited reference was a revised European consensus on the definition and diagnosis of sarcopenia;the most cited keywords were related to physiological factors of diabetes, sarcopenia and related conditions, such as “insulin resistance”, “skeletal muscle”, “body composition”, “risk” and “prevalence”. Conclusion: With more and more studies on the relationship between diabetic sarcopenia, this study presents the current status and trend of research related to diabetic sarcopenia over the past nearly 30 years through the visualization software CiteSpace. It can help researchers identify potential collaborators and partner institutions, hotspots and research frontiers in the field of diabetic sarcopenia. However, our work is only based on the English language literature in the WoSCC database, and for future studies, we recommend that researchers explore the literature from multiple databases to enhance the scope of their research. 展开更多
关键词 DIABETES SARCOPENIA BIBLIOMETRICS Research trends Citespace
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Climate Trends and Their Impact on Sorghum Production in Marigat, Baringo County: A Historical Analysis
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作者 Kennedy O. Okuku Japheth O. Onyando +1 位作者 Romulus O. Okwany Clement K. Kiptum 《Open Journal of Modern Hydrology》 CAS 2024年第2期106-129,共24页
Climate is subject to fluctuations in the majority of the world, mainly caused by rainfall as well as temperature variations. Climate fluctuations in Kenya have resulted in the spread of desert-like conditions in the ... Climate is subject to fluctuations in the majority of the world, mainly caused by rainfall as well as temperature variations. Climate fluctuations in Kenya have resulted in the spread of desert-like conditions in the ASALs region, such as Marigat in Baringo County. As a county, Baringo experiences great variations in climate annually, as well as uncertainty in expected rains, thereby negatively impacting the production of crops such as sorghum. This study applied the rainfall anomaly index (RAI), standardised precipitation evapotranspiration index (SPEI), standard precipitation index (SPI), and Mann-Kendall (MK) statistical test for trends on historical climatic data in analysing both temperature and precipitation data over the period 1990 to 2022 to determine their trend, patterns and how they affect the production of sorghum crops. The machine learning method (R studio) with inputs was used to calculate the SPI, SPEI, RAI and MK trend test. The rainfall varied from below average to above average during the study period with no clear pattern in the RAI, SPEI and SPI values. The years 2020 and 2000 stood out as they had higher and lower rainfall than usual, respectively. The Marigat area generally experienced more rainfall during the high/long rainfall season (AMJJ). The MK trend test on average monthly rainfall, SOND, AMJJ, and annual precipitation confirmed a positive trend in precipitation. However, the short rainy season (SOND) was found to be the most variable period for rainfall, and there was a slight increase in daily average temperatures during this season. 展开更多
关键词 trends PRECIPITATION Temperature RAI SPI SPEI and MK
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