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Evaluating the weekly changes in terrestrial water storage estimated by two different inversion strategies in the Amazon River Basin
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作者 Bo Zhong Xianpao Li +2 位作者 Qiong Li Jiangtao Tan Xianyun Dai 《Geodesy and Geodynamics》 EI CSCD 2023年第6期614-626,共13页
In this study,we estimated the weekly Gravity Recovery and Climate Experiment(GRACE)spherical harmonic(SH)solutions and regional mascon solutions using GRACE-based Geopotential Difference(GPD)data and investigated the... In this study,we estimated the weekly Gravity Recovery and Climate Experiment(GRACE)spherical harmonic(SH)solutions and regional mascon solutions using GRACE-based Geopotential Difference(GPD)data and investigated their abilities in retrieving terrestrial water storage(TWS)changes over the Amazon River Basin(ARB)from January 2003 to February 2013.The performance of the weekly GPD-SH and GPDmascon solutions was evaluated by comparing them with the weekly GFZ-SH solutions,Global Land Data Assimilation Systems(GLDAS)-NOAH hydrological model outputs,and monthly GFZ-SH,GPD-SH,and CSRmascon solutions in the spatio-temporal and spectral domains.The results demonstrate that the weekly GPD-SH and GPD-mascon present good consistency with the weekly GFZ-SH solutions and GLDAS-NOAH estimates in the spatio-temporal domains,but GPD-mascon presents stronger signal amplitudes and more spatial details.The comparison of the monthly average of weekly estimates and monthly solutions demonstrates that the weekly GPD-mascon and GFZ-SH with DDK1 filtering are close to the monthly CSRmascon and GFZ-SH solutions,respectively.However,the signal amplitudes of TWS changes from GPD-SH and GFZ-SH with 650 km Gaussian filtering are smaller than the monthly solutions,and the corresponding Root Mean Square Errors between the TWS change time series from the monthly average of weekly solutions and monthly estimates are 18.12 mm(GPD-mascon),18.81 mm(GFZ-SH-DDK1),24.93 mm(GPDSH-G650km),and 33.07 mm(GFZ-SH-G650km),respectively.Additionally,the TWS change time series derived from weekly solutions present more high-frequency time-varying information than monthly solutions.Furthermore,the 300 km Gaussian filtering can improve the signal amplitudes of TWS changes from the weekly GPD-SH solutions more than those with 650 km Gaussian filtering,but the corresponding noise level is higher.The weekly GPD-SH and GPD-mascon solutions can extend the application scopes of GRACE and provide good complements to the current GRACE monthly solutions. 展开更多
关键词 Terrestrial water storage change Amazon River Basin GRACE-based geopotential differences weekly solutions Performance evaluation
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Did weekly economic index and volatility index impact US food sales during the first year of the pandemic?
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作者 Narasingha Das Partha Gangopadhyay 《Financial Innovation》 2023年第1期1502-1524,共23页
We explore the impacts of economic and financial dislocations caused by COVID-19 pandemic shocks on food sales in the United States from January 2020 to January 2021.We use the US weekly economic index(WEI)to measure ... We explore the impacts of economic and financial dislocations caused by COVID-19 pandemic shocks on food sales in the United States from January 2020 to January 2021.We use the US weekly economic index(WEI)to measure economic dislocations and the Chicago Board Options Exchange volatility index(VIX)to capture the broader stock market dislocations.We validate the NARDL model by testing a battery of models using the autoregressive distributed lags(ARDL)methodology(ARDL,NARDL,and QARDL specifications).Our study postulates that an increase in WEI has a significant negative long-term effect on food sales,whereas a decrease in WEI has no statistically significant(long-run)effect.Thus,policy responses that ignore asymmetric effects and hidden cointegration may fail to promote food security during pandemics. 展开更多
关键词 COVID-19 Food sales US weekly economic index CBOE’s volatility index ARDL model Bewley transformation NARDL model QARDL model
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泰索帝Weekly方案配合放疗治疗局部晚期非小细胞肺癌近期疗效评价 被引量:1
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作者 刘宏 王庆伟 +2 位作者 乔乃安 程玉峰 刘惠中 《肿瘤防治研究》 CAS CSCD 2002年第4期263-263,共1页
关键词 泰索帝 weekly方案 晚期 非小细胞肺癌 近期疗效 放射疗法 局部治疗
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放疗配合泰索帝Weekly方案治疗局部晚期非小细胞肺癌近期疗效观察
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作者 刘宏 王庆伟 +2 位作者 乔乃安 李贞 程玉峰 《山东医药》 CAS 北大核心 2001年第18期29-30,共2页
关键词 晚期非小细胞肺癌 放射治疗 药物治疗 泰索帝 weekly方案
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Once-versus Twice-weekly Bortezomib Induction Therapy with Dexamethasone in Newly Diagnosed Multiple Myeloma 被引量:6
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作者 王雅丹 艾利莎 +3 位作者 崔国惠 Bhuveshwarnath Gowrea 李勉 胡豫 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第4期495-500,共6页
In this study,we administered a modified schedule of weekly intravenous Bortezomib at 1.6 mg/m 2 with dexamethasone(BD) and compared it to the standard 1.3 mg/m 2 twice-weekly BD regimen in Chinese patients with newly... In this study,we administered a modified schedule of weekly intravenous Bortezomib at 1.6 mg/m 2 with dexamethasone(BD) and compared it to the standard 1.3 mg/m 2 twice-weekly BD regimen in Chinese patients with newly diagnosed multiple myeloma(MM).We assessed the difference in efficacy,safety profile and survival between the once-weekly and twice-weekly cohorts(13 vs.24 patients).The over response rate was similar with both arms of the study,being 77% in the once-weekly schedule and 74.9% in the twice-weekly schedule(P=0.690).The median overall survival was not reached in either schedule.Also,the median progression-free survival and duration of response of the once-weekly schedule did not significantly differ from those of the twice-weekly schedule(8 months vs.10 months,P=0.545 and 6 months vs.7 months,P=0.467 respectively).Peripheral sensory neuropathy and grade 3/4 hematologic toxic effects were more frequently reported in the twice-weekly schedule than the once-weekly schedule,but there was no statistically significant difference.This preliminary experience in Chinese patients with newly diagnosed MM indicated that once-weekly infusion of Bortezomib plus dexamethasone may improve safety without affecting outcome. 展开更多
关键词 BORTEZOMIB multiple myeloma weekly schedule response rate adverse event
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Weekly pattern of emergency room admissions for peptic ulcers:A population-based study 被引量:1
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作者 Li-Ting Kao Ming-Chieh Tsai +2 位作者 Herng-Ching Lin Femi Pai Cha-Ze Lee 《World Journal of Gastroenterology》 SCIE CAS 2015年第11期3344-3350,共7页
AIM:To investigate variations in the incidence of peptic ulcers(PUs) in Taiwan by day of the week within age subgroups.METHODS:Ambulatory care data were retrieved from the Longitudinal Health Insurance Database 2000.T... AIM:To investigate variations in the incidence of peptic ulcers(PUs) in Taiwan by day of the week within age subgroups.METHODS:Ambulatory care data were retrieved from the Longitudinal Health Insurance Database 2000.There were 7204 subjects≥18 years-old with an emergency room admission claim for the treatment of PUs,resulting in a total of 9234 emergency room visits for PUs between 2009 and 2011.Data was divided into the seven days of the week and an additional variable for holidays.One-way analysis of variance was used to examine associations among the daily mean number of PU emergency room admissions and holidays/weekends/weekdays.RESULTS:One-way analysis of variance showed that there was a significant difference in emergency room admissions for PUs by the day of the week(P<0.001),with admission more likely to occur on Sundays or holidays than weekdays within the total and working populations.The weekday patterns of admission were similar for the patients aged 18-64 years and≥65years of age.Holidays,followed by Sundays,had higher PU admissions than the mean daily PU emergency room admissions.Furthermore,inclusion of only those treated for PUs with hemorrhage or perforation,Sundays and holidays had higher mean emergency room admissions than other days.Inclusion of patients who diagnosed with Helicobacter pylori infection,only holidays had higher mean emergency room admissions than other days.Inclusion of patients who had been prescribed non-steroidal anti-inflammatory drugs(NSAIDs)for over30 d,Sundays and holidays had higher mean PU ER admissions than other non-holiday weekdays.CONCLUSION:There is a higher incidence of emergency room admission for PUs on weekends than on weekdays for the total and working populations. 展开更多
关键词 CHRONOLOGY EPIDEMIOLOGY PEPTIC ULCER weekly patter
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Three Weeks Carboplatin/Paclitaxel versus Weekly Regimen in Egyptian Women Cohort Treated for Ovarian Carcinoma 被引量:1
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作者 A. Mounir E. E. Ibrahim 《Journal of Cancer Therapy》 2021年第2期78-85,共8页
<strong>Introduction: </strong><span style="font-family:""><span style="font-family:Verdana;">Epithelial Ovarian Carcinoma (EOC) comprises the vast majority (almost 90%... <strong>Introduction: </strong><span style="font-family:""><span style="font-family:Verdana;">Epithelial Ovarian Carcinoma (EOC) comprises the vast majority (almost 90%) of ovarian carcinomas. Chemotherapy is the main treatment in ovarian cancers. The standard of care in the chemotherapeutic is the combination of a platinum (carboplatin or cisplatin) and a taxane (paclitaxel or docetaxel). Studies were done to determine whether this combination to be given weekly or every 3 weeks. </span><b><span style="font-family:Verdana;">Patient and Method: </span></b><span style="font-family:Verdana;">Inclusion criteria: 1) Female patients between the ages of 17 - 78 years. 2) Baseline hematological, renal and liver laboratory profiles were within accepted ranges. 3) Performance status of the patients was 0-II. 4) Patients were pathologically proven ovarian cancer. 5) A follow-up period for at least 6 months was required. Exclusion criteria: 1) Patients who had double malignancy were excluded. 2) Performance status more than II. 3) Other comorbidity. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">We reviewed 69 female patients with EOC, with 60% received every three weeks regimen. Mean age was 53.22 years. At a median follow up of 45.9 months, there was no significant different between the two protocols in terms of mean PFS, 62.35 months (95% CI: 50.08 - 74.63 months) for the three-weekly cohort, and 69.25 months (95% CI: 55.24 - 83.26 months) for weekly protocol (p = 0.613). The three weekly regimen patients had a higher incidence of hospital admission (40% vs 18.5% for the weekly protocol patients), but it didn’t reach a statistical significance (p = 0.063). The three weekly protocol had a significantly higher incidence of causing a neutropenic fever (p = 0.003). </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">In our cohort of Egyptian women with EOC, no significant difference in PFS was found when compared the weekly Carboplatin/paclitaxel when compared to the classic three weeks, although the weekly protocol may be causing less febrile neutropenia and fewer hospital admissions.</span></span> 展开更多
关键词 Epithelial Ovarian Carcinoma Carboplatin/Paclitaxel weekly versus Every Three weeks
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Prediction Model of Weekly Retail Price for Eggs Based on Chaotic Neural Network 被引量:3
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作者 LI Zhe-min CUI Li-guo +4 位作者 XU Shi-wei WENG Ling-yun DONG Xiao-xia LI Gan-qiong YU Hai-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2292-2299,共8页
This paper establishes a short-term prediction model of weekly retail prices for eggs based on chaotic neural network with the weekly retail prices of eggs from January 2008 to December 2012 in China.In the process of... This paper establishes a short-term prediction model of weekly retail prices for eggs based on chaotic neural network with the weekly retail prices of eggs from January 2008 to December 2012 in China.In the process of determining the structure of the chaotic neural network,the number of input layer nodes of the network is calculated by reconstructing phase space and computing its saturated embedding dimension,and then the number of hidden layer nodes is estimated by trial and error.Finally,this model is applied to predict the retail prices of eggs and compared with ARIMA.The result shows that the chaotic neural network has better nonlinear fitting ability and higher precision in the prediction of weekly retail price of eggs.The empirical result also shows that the chaotic neural network can be widely used in the field of short-term prediction of agricultural prices. 展开更多
关键词 chaos theory chaotic neural network neural network technology short-term prediction weekly retail price of eggs
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How Do Weekly Magazines Provide Information on Urogenital Cancer to the Public in Aged Societies?
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作者 Masayoshi Nagata Tomoko Matsumura Masahiro Kami 《Open Journal of Urology》 2013年第6期246-247,共2页
Little information on cancer coverage rather than newspaper and television is available. Japanese weekly magazines have a circulation of over 2,700,000 per week. To examine how they delivered urogenital cancer informa... Little information on cancer coverage rather than newspaper and television is available. Japanese weekly magazines have a circulation of over 2,700,000 per week. To examine how they delivered urogenital cancer information to the public, cancer-related articles and advertisements in six major Japanese weekly magazines from 2009 to 2010 was analyzed. 1.8% of total articles and advertisements were cancer-related. Prostate cancer (n = 119) was the second-most common topic, following lung cancer (n = 145), whereas only three articles were published on kidney or bladder cancer. The 53 articles on therapies for prostate cancer comprised radiotherapy (n = 29), surgery (n = 16), chemotherapy (n = 4), and others (n = 4). All 42 comments or interviews were cited in the article on prostate cancer, while 26 of them were attributed to only two famous doctors. Although cancer coverage in weekly magazines could be useful to spread information on prostate cancer, we should recognize their considerable bias based on a disproportionate emphasis. 展开更多
关键词 CANCER COVERAGE weekly MAGAZINE PROSTATE CANCER
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Exenatide once weekly combined with metformin reduced glycemic variability in type 2 diabetes by using flash glucose monitoring system
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作者 Yang Li Min-Min Han +5 位作者 Qiong He Zi-Ang Liu Dong Liang Jing-Tian Hou Yi Zhang Yun-Feng Liu 《World Journal of Diabetes》 SCIE 2020年第12期654-665,共12页
BACKGROUND Multiple studies demonstrate that fluctuating blood glucose level produces greater damage compared with sustained hyperglycemia.Flash glucose monitoring system is an effective method in documenting blood gl... BACKGROUND Multiple studies demonstrate that fluctuating blood glucose level produces greater damage compared with sustained hyperglycemia.Flash glucose monitoring system is an effective method in documenting blood glucose variability,contributing to better glucose management and reduced hypoglycemic event occurrence.AIM To investigate the improvement in glycemic variability(GV),blood glucose level,and metabolic indexes of patients with type 2 diabetes mellitus after combined treatment of exenatide once weekly(EXQW)and metformin.METHODS Twenty-five patients with type 2 diabetes mellitus suffering from poor blood glucose control under metformin treatment were recruited.The recruited patients were prescribed with oral metformin only(maintaining a dosage of metformin at≥1500 mg/day)for 2 wk(screening period),and then given EXQW(2 mg,subcutaneous injection)for 12 wk(experimental period).The flash glucose monitoring system was used to document blood glucose values during the screening period and the last 2 wk of the experimental period.RESULTS Four patients were excluded for various reasons,yielding a total of 21 patients,including 17 males and 4 females,with an average age of 48.8 years,who completed this study.The estimated glycated hemoglobin,mean blood glucose,fasting and postprandial blood glucose levels,and percentage of blood glucose above 7.8 mmol/L decreased compared to those at baseline(P=0.003,0.003,0.008,0.010,0.014,0.017,and 0.005,respectively),while the percentage of blood glucose between 3.9 and 7.8 mmol/L significantly increased(P=0.005).Parameters of GV including standard deviation of blood glucose,mean amplitude of glycemic excursions,mean of daily difference,area under the curve difference between percentiles 25 and 75,and area under the curve difference between percentiles 10 and 90 were significantly lower compared to that of baseline(P=0.017,0.006,0.000,0.024,0.036,respectively).The durations of blood glucose below 3.9 mmol/L during the day and nocturnal periods significantly increased after treatment(P=0.041 and 0.028,respectively),but there was no significant increase in severe hypoglycemia(<3.0 mmol/L)compared with that at baseline(P=0.207).In addition,some metabolic indicators improved after EXQW treatment.CONCLUSION EXQW combined with metformin can effectively improve blood glucose levels,reduce GV,and improve metabolic indicators.However,there is still a risk of nocturnal hypoglycemia,and careful attention should be paid to patients with EXQW treatment. 展开更多
关键词 Flash glucose monitoring Glycemic variability Type 2 diabetes mellitus Exenatide once weekly
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环境所召开China CDC Weekly投稿培训会
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作者 《环境卫生学杂志》编辑部 《环境卫生学杂志》 2019年第4期410-410,共1页
为推动China CDC Weekly投稿工作及提高投稿稿件质量,环境所于2019年7月4日在潘家园工作区组织召开China CDC Weekly投稿培训会,邀请China CDC Weekly编辑部谭枫主任做专题培训。施小明所长主持会议,姚孝元副所长、徐东群副所长、China ... 为推动China CDC Weekly投稿工作及提高投稿稿件质量,环境所于2019年7月4日在潘家园工作区组织召开China CDC Weekly投稿培训会,邀请China CDC Weekly编辑部谭枫主任做专题培训。施小明所长主持会议,姚孝元副所长、徐东群副所长、China CDC Weekly相关编辑和所内审稿专家,相关科室负责人及业务骨干30余人参加了这次培训。 展开更多
关键词 CDC 编辑部 China CDC weekly 稿件质量
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A Study of Conceptual Metaphors in Obama's Weekly Addresses
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作者 刘春迪 《海外英语》 2017年第1期211-215,共5页
Conceptual metaphor plays an important role in delivering political speeches for it can make abstract and complicated political concepts into clear and vivid statements. Therefore, it is often used by politicians. The... Conceptual metaphor plays an important role in delivering political speeches for it can make abstract and complicated political concepts into clear and vivid statements. Therefore, it is often used by politicians. The American President Barack Obama often utilizes metaphors in his speeches and good at utilizing them. The weekly address is a typical representative of political discourse. This article is intended to analyze the conceptual metaphors used in Obama's weekly addresses on the basis of the conceptual metaphor theory proposed by Lakoff and Johnson.The analysis shows that there are three categories of conceptual metaphors used frequently in Obama's weekly addresses, which can be learned that how Obama uses conceptual metaphors to make speeches more vivid. 展开更多
关键词 weekly address conceptual metaphor LAKOFF OBAMA
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A Qualitative Study on the Psychological Experience of Pregnant Women with Abnormal Induced Abortion of Fetuses under 20 Weeks of Pregnancy
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作者 Chunrong Pu 《Open Journal of Obstetrics and Gynecology》 2023年第7期1133-1141,共9页
Objective: This paper aims to understand the psychological experience and needs of pregnant women who need induction of labor due to fetal abnormalities at less than 20 weeks of gestation through in-depth interviews. ... Objective: This paper aims to understand the psychological experience and needs of pregnant women who need induction of labor due to fetal abnormalities at less than 20 weeks of gestation through in-depth interviews. Methods: Using the phenomenological research method in qualitative research, 12 pregnant women with fetal abnormalities less than 20 weeks of gestation in the obstetrics department of a hospital from January to April 2023 were selected as the research objects for semi-structured in-depth interviews. After information was collected to saturation, Colaizzi content analysis method was used to sort out, analyze and refine the data. Results: Through the interview results, three themes were refined from the transcript. Those are: 1) the support and assistance needed during the induction of labor;2) inner feelings after labor induction;3) The vision of future life. Conclusion: Abnormal fetal development at <20 weeks of gestation can cause anxiety, depression, guilt, loneliness and other negative emotions for pregnant women, and they need to get corresponding psychological support, especially during the period from fetal abnormality to induction of labor, pregnant women have to experience many physical and mental suffering, and need to get the care of family, relatives, friends, medical staff and society. Medical staff can help them seek multi-directional support, provide professional knowledge, and help them with self-management. 展开更多
关键词 <20 weeks of Gestation Fetal Abnormalities Induction of Labor Psychological Experience Qualitative Research
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Machine Learning and Pattern Analysis Identify Distinctive Influences from Long-term Weekly Net Ecosystem Exchange at Four Deciduous Woodland Locations
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作者 David A.Wood 《Research in Ecology》 2022年第4期13-38,共26页
A methodology integrating correlation,regression(MLR),machine learning(ML),and pattern analysis of long-term weekly net ecosystem exchange(NEE)datasets are applied to four deciduous broadleaf forest(DBF)sites forming ... A methodology integrating correlation,regression(MLR),machine learning(ML),and pattern analysis of long-term weekly net ecosystem exchange(NEE)datasets are applied to four deciduous broadleaf forest(DBF)sites forming part of the AmeriFlux(FLUXNET2015)database.Such analysis effectively characterizes and distinguishes those DBF sites for which long-term NEE patterns can be accurately predicted using the recorded environmental variables,from those sites cannot be so delineated.Comparisons of twelve NEE prediction models(5 MLR;7 ML),using multi-fold cross-validation analysis,reveal that support vector regression generates the most accurate and reliable predictions for each site considered,based on fits involving between 16 and 24 available environmental variables.SVR can accurately predict NEE for datasets for DBF sites US-MMS and US-MOz,but fail to reliably do so for sites CA-Cbo and MX-Tes.For the latter two sites the predicted versus recorded NEE weekly data follow a Y≠X pattern and are characterized by rapid fluctuations between low and high NEE values across leaf-on seasonal periods.Variable influences on NEE,determined by their importance to MLR and ML model solutions,identify distinctive sets of the most and least influential variables for each site studied.Such information is valuable for monitoring and modelling the likely impacts of changing climate on the ability of these sites to serve as long-term carbon sinks.The periodically oscillating NEE weekly patterns distinguished for sites CA-Cbo and MX-Tes are not readily explained in terms of the currently recorded environmental variables.More detailed analysis of the biological processes at work in the forest understory and soil at these sites are recommended to determine additional suitable variables to measure that might better explain such fluctuations. 展开更多
关键词 EDDY-COVARIANCE CO_(2)-flux influences Multi-fold cross validation weekly NEE pattern analysis Site specific NEE influences FLUXNET2015 protocols
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从儒家经典到课本选文:清末民初读经科向国文科的转化与融入
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作者 张心科 《宁波大学学报(教育科学版)》 2024年第1期64-71,共8页
民国初年读经被取消后又被反复提倡,但清末的读经科部分转化、融入了国文科并影响了国文科的发展:国文科课程目标中的“德”由读经科转入,教材中部分课文是对读经科中的整本儒家经典的节选,教学中的诵读法也来自读经科。转化的发生及其... 民国初年读经被取消后又被反复提倡,但清末的读经科部分转化、融入了国文科并影响了国文科的发展:国文科课程目标中的“德”由读经科转入,教材中部分课文是对读经科中的整本儒家经典的节选,教学中的诵读法也来自读经科。转化的发生及其成功,主要原因是:读经科改变了形式,顺应了现代教育(国文)的变化,教育目的由培养臣民转为培养公民,教育形式由私塾中的单个点拨到学堂中的班级授课,国文教材形态由专书变为选文,考试文体由八股变为古文。 展开更多
关键词 清末民初 读经科 国文科
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文旅视域下的西安新锐青年时装周发展研究
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作者 王田薇 刘欣怡 《服装设计师》 2024年第5期109-112,共4页
文章聚焦于服饰文化传播项目“西安新锐青年时装周”,以文旅视域为切入点,对该项目的意义与潜在发展空间进行分析;结合2023年“西安新锐青年时装周”院校板块“无界——西安美术学院服装系本科毕业作品展”与城市名片大唐不夜城项目的... 文章聚焦于服饰文化传播项目“西安新锐青年时装周”,以文旅视域为切入点,对该项目的意义与潜在发展空间进行分析;结合2023年“西安新锐青年时装周”院校板块“无界——西安美术学院服装系本科毕业作品展”与城市名片大唐不夜城项目的落地执行,进一步论述了当下该服饰文化传播与文旅项目的发展,力求在促进院校培养新锐时尚文化与城市形象文旅项目发展的同时,为当今文旅与服饰文化的进一步融合提供一定思路。 展开更多
关键词 西安新锐青年时装周 文旅视域 服饰文化传播
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混凝土徐变柔度函数的高效逼近方法
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作者 向华伟 荣华 +2 位作者 范兴朗 耿岩 白林洪 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第8期1689-1696,共8页
混凝土徐变是引起安全壳预应力损失的主要因素之一,采用指数算法求解混凝土徐变效应时需要将混凝土徐变柔度函数采用Dirichlet级数表达,如何获得精确表征柔度函数的Dirichlet级数是实现指数算法的关键。基于连续延迟谱法,本文提出一种... 混凝土徐变是引起安全壳预应力损失的主要因素之一,采用指数算法求解混凝土徐变效应时需要将混凝土徐变柔度函数采用Dirichlet级数表达,如何获得精确表征柔度函数的Dirichlet级数是实现指数算法的关键。基于连续延迟谱法,本文提出一种求解拉普拉斯逆变换的Weeks方法来逼近Dirichlet级数。对工程中常用的CEB MC90徐变模型,构建了基于Weeks方法的Dirichlet级数逼近算法,并给出了提高方法效率的相关参数取值范围。结果表明,提出的方法仅需对原混凝土徐变柔度函数求1阶导数,即可返回时域函数的显示表达式,避免了高阶求导存在计算复杂和计算效率低的问题。将本文方法计算结果与原柔度函数解析解进行对比,验证了方法的有效性。 展开更多
关键词 混凝土安全壳 混凝土徐变 柔度函数 DIRICHLET级数 连续延迟谱 weeks方法
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延长产蛋周期对白来航鸡和北京油鸡淘汰鸡屠宰性能和肉品质的影响
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作者 杨涵涵 梁锐萍 +8 位作者 李云雷 倪爱心 袁经纬 王园美 韩昕彤 宗云鹤 陈超 陈继兰 孙研研 《中国家禽》 北大核心 2024年第7期12-17,共6页
试验旨在研究延长不同品种鸡产蛋周期对其淘汰鸡的屠宰性能、肉品质和肌肉主要营养成分含量的影响。试验选取52、72和100周龄的北京油鸡和白来航鸡母鸡,比较不同品种不同淘汰周龄各指标的差异。结果显示:延长产蛋周期对两品种体重无显... 试验旨在研究延长不同品种鸡产蛋周期对其淘汰鸡的屠宰性能、肉品质和肌肉主要营养成分含量的影响。试验选取52、72和100周龄的北京油鸡和白来航鸡母鸡,比较不同品种不同淘汰周龄各指标的差异。结果显示:延长产蛋周期对两品种体重无显著影响(P>0.05)。100周龄北京油鸡半净膛重与52周龄无显著差异(P>0.05),但显著高于72周龄(P<0.05),全净膛重显著高于52和72周龄(P<0.05)。100周龄白来航鸡腹脂重和腹脂率显著低于72周龄(P<0.05),北京油鸡也有类似趋势。此外,北京油鸡胸肌滴水损失和蒸煮损失分别为3.10%~4.77%和13.50%~18.90%,均高于白来航鸡(P>0.05)。胸肌主要营养成分水分、粗蛋白质、总饱和脂肪酸和总不饱和脂肪酸等在品种间和周龄间均无显著差异(P>0.05)。研究表明,延长产蛋周期对北京油鸡和白来航鸡的体重和主要营养成分没有显著影响,但显著降低高产蛋鸡的腹脂重和腹脂率,改善胴体组成。 展开更多
关键词 淘汰蛋鸡 屠宰性能 肉品质 100周龄
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网络结构自主权的前因、后果及作用条件研究
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作者 朱明洋 张玉利 吴晓波 《管理工程学报》 CSCD 北大核心 2024年第3期1-13,共13页
网络结构自主权是最初由Burt在结构洞理论基础上所提出的一个用于描述“网络结构空间与行动自由”的概念,但并未像结构洞概念一样在战略和创新领域引起足够重视。基于整合关系内容与关系结构双层面分析视角,本研究尝试将结构自主权引入... 网络结构自主权是最初由Burt在结构洞理论基础上所提出的一个用于描述“网络结构空间与行动自由”的概念,但并未像结构洞概念一样在战略和创新领域引起足够重视。基于整合关系内容与关系结构双层面分析视角,本研究尝试将结构自主权引入到关系强度-商业模式创新实现路径中,同时考察环境不确定性对整个路径的调节作用,即构建并验证了一个有调节的中介模型。研究发现:(1)关系强度积极影响网络结构自主权和商业模式创新;(2)网络结构自主权在关系强度与商业模式创新间发挥中介作用;(3)环境不确定性负向调节网络结构自主权与商业模式创新间关系,并对“关系强度-结构自主权-商业模式创新”整条路径产生显著的消极影响。本研究不仅有助于促进对结构自主权概念的认识与关注,推动网络结构自主权研究,也能够为解决“网络行动空间是否影响创新”和“如何实现商业模式创新”等问题提供有益启示。 展开更多
关键词 结构自主权 强关系 弱关系 商业模式创新 不确定性
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来自多方的声音:构建中国开放科学创新生态——第十届中国开放获取推介周(China OA Week)会议综述 被引量:9
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作者 黄金霞 汪煊 +3 位作者 杨恒 刘静羽 张智雄 刘细文 《农业图书情报学报》 2022年第1期49-61,共13页
[目标/意义]2021年第十届中国开放获取推介周(10th China OA Week)的主题为“开放科学的意义和影响”,标志着中国最主要的开放获取平台主题正式转向开放科学,契合形势发展需要。[方法/过程]本届会议邀请到国内外的多方专家与代表,分专... [目标/意义]2021年第十届中国开放获取推介周(10th China OA Week)的主题为“开放科学的意义和影响”,标志着中国最主要的开放获取平台主题正式转向开放科学,契合形势发展需要。[方法/过程]本届会议邀请到国内外的多方专家与代表,分专题探讨开放科学目标、关键问题、实践案例并提出发展建议。[结果/结论]会议呼吁构建中国开放创新生态,初步勾画出中国开放科学发展现状。响应国家提出的推动开放科学发展要求,China OA Week平台及其研讨成果将持续助力中国开放科学事业的推进。 展开更多
关键词 中国开放获取推介周 开放科学 中国现状 实施路线图 中华人民共和国科学技术进步法
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