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基于Gross情绪调节理论的心理护理对耐药结核病患者心理应激、治疗依从性及生活质量的影响
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作者 邵丽波 崔晓华 +2 位作者 孙艳芳 张亢亢 杨莉 《医学理论与实践》 2024年第5期852-854,共3页
目的:探讨基于Gross情绪调节理论的心理护理对耐药结核病(DR-TB)患者心理应激水平、治疗依从性及生活质量的影响。方法:使用随机数表法将2022年1—12月在我院就诊的80例DR-TB患者分为对照组(n=40)和观察组(n=40)。对照组给予常规护理,... 目的:探讨基于Gross情绪调节理论的心理护理对耐药结核病(DR-TB)患者心理应激水平、治疗依从性及生活质量的影响。方法:使用随机数表法将2022年1—12月在我院就诊的80例DR-TB患者分为对照组(n=40)和观察组(n=40)。对照组给予常规护理,观察组给予在常规护理基础上基于Gross情绪调节理论的心理护理。比较两组心理应激水平、治疗依从性及生活质量。结果:干预后,两组BDI、BAI评分均下降,且观察组BDI、BAI评分均低于对照组(P<0.05);观察组MMAS-8评分高于对照组(P<0.05);干预后,两组QLI-TB评分均上升,且观察组QLI-TB评分高于对照组(P<0.05)。结论:基于Gross情绪调节理论的心理护理能有效改善DR-TB患者焦虑、抑郁情绪,对提高患者治疗依从性及生活质量有较大意义。 展开更多
关键词 耐药结核病 gross情绪调节理论 心理应激 治疗依从性 生活质量
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Gross Alpha and Beta Activities and Related Lifetime Risks Assessment Due to Ingestion of Drinking Water from Different Sources in the District of Abidjan, Cote d’Ivoire
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作者 Ponaho Claude Kezo Issa Konate Dabo Salif Ignace Agba 《World Journal of Nuclear Science and Technology》 CAS 2024年第1期86-96,共11页
Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the ... Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the objective of this study was to assess the risk of cancer due to the ingestion of alpha and beta emitting radionuclides in the different types of water consumed in the region. A total of 63 water samples with 43 tap water samples, 5 bottled mineral water and 15 sachet water samples was collected and taken to GAEC laboratory for analysis. The low background Gas-less Automatic Alpha/Beta counting system (Canberra iMatic<sup>TM</sup>) was used to determine alpha and beta activity concentrations. Activity concentrations of both gross alpha and gross beta obtained in water sample were respectively lower than the WHO recommended limits of 0.1 Bq/l and 1 Bq/l. Also, the annual effective dose and total equivalent effective dose found in mineral bottled water samples were higher than in other types of water. The assessment of radiological lifetime risk has shown values of cancer risk due to ingestion alpha and beta emitters lower than recommended limit. These results indicate that there is no health hazard associated to consumption of water in the District of Abidjan. 展开更多
关键词 gross Alpha and Beta Activities Drinking Water Effective Dose Radiological Lifetime Risks
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融合经验知识与深度强化学习的久棋Alpha-Beta算法优化研究
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作者 张小川 杨小漫 +3 位作者 涂飞 王鑫 严明珠 梁渝卓 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第5期115-120,共6页
藏族久棋作为一种传统的棋类博弈游戏,具备高度复杂的规则体系以及变幻莫测的棋局演变。传统的博弈策略在面对不同对手和棋局时不稳定,性能差,需要新的方法提高藏族久棋AI的博弈水平。以藏族久棋为研究对象,针对布局阶段,改进传统Alpha-... 藏族久棋作为一种传统的棋类博弈游戏,具备高度复杂的规则体系以及变幻莫测的棋局演变。传统的博弈策略在面对不同对手和棋局时不稳定,性能差,需要新的方法提高藏族久棋AI的博弈水平。以藏族久棋为研究对象,针对布局阶段,改进传统Alpha-Beta剪枝搜索算法,并结合经验知识,融入深度强化学习算法完成棋盘布局合理性的落子选择,以此为后续阶段铺路。在行棋阶段与飞子阶段,结合经验知识使用Alpha-Beta算法,完成行棋路径。最后,将所提算法和策略集成于久棋AI程序,在中国计算机博弈锦标赛中取得了良好的成绩,验证了该方法的有效性。 展开更多
关键词 藏族久棋 经验知识 alpha-beta算法 深度强化学习 计算机博弈
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Effect of VOJTA Therapy on Gross Motor Function in Children with Cerebral Palsy
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作者 Tian Ma Ceng Li Yabo Liu 《Open Journal of Pediatrics》 2024年第2期359-363,共5页
Objective: To investigate the effect of VOJTA therapy on gross motor function in children with cerebral palsy. Methods: The 86 children with cerebral palsy were all from the First People’s Hospital of Jingzhou City f... Objective: To investigate the effect of VOJTA therapy on gross motor function in children with cerebral palsy. Methods: The 86 children with cerebral palsy were all from the First People’s Hospital of Jingzhou City from January 2023-December 2023, and were divided into the control group and the study group with 43 cases according to the principle of voluntariness. Results: In terms of total effective rate of treatment, the gross motor function scale-88 (GMFM-88) was used to evaluate the effective rate before and after treatment, and the effective rate of the study group was higher than that of the control group, and the difference was statistically significant, and the scores of gross motor items of GMFM-88 were better than those of the control group after treatment, and the difference was statistically significant (P 0.05). Conclusion: The application of VOJTA therapy in the treatment of children with cerebral palsy can not only promote the rehabilitation of gross motor function, but also help to improve the treatment effect, and the earlier the treatment, the better. 展开更多
关键词 VOJTA Therapy Children with Cerebral Palsy gross Motor Function
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Safety and efficacy of transcatheter arterial embolization in autosomal dominant polycystic kidney patients with gross hematuria: Six case reports
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作者 Wei-Fan Sui Yun-Xin Duan +2 位作者 Jian-Yun Li Wei-Bin Shao Jian-Hua Fu 《World Journal of Clinical Cases》 SCIE 2024年第11期1954-1959,共6页
BACKGROUND To retrospectively report the safety and efficacy of renal transcatheter arterial embolization for treating autosomal dominant polycystic kidney disease(ADPKD)patients with gross hematuria.CASE SUMMARY The ... BACKGROUND To retrospectively report the safety and efficacy of renal transcatheter arterial embolization for treating autosomal dominant polycystic kidney disease(ADPKD)patients with gross hematuria.CASE SUMMARY The purpose of this study is to retrospectively report the safety and efficacy of renal transcatheter arterial embolization for treating ADPKD patients with gross hematuria.Materials and methods:During the period from January 2018 to December 2019,renal transcatheter arterial embolization was carried out on 6 patients with polycystic kidneys and gross hematuria.Renal arteriography was performed first,and then we determined the location of the hemorrhage and performed embolization under digital subtraction angiography monitoring.Improvements in routine blood test results,routine urine test results,urine color and postoperative reactions were observed and analyzed.Results:Renal transcatheter arterial embolization was successfully conducted in 6 patients.The indices of 5 patients and the color of gross hematuria improved after surgery compared with before surgery.No severe complication reactions occurred.CONCLUSION For autosomal dominant polycystic kidney syndrome patients with gross hematuria,transcatheter arterial embolization was safe and effective. 展开更多
关键词 Renal artery Autosomal dominant polycystic kidney disease gross hematuria Interventional radiology EMBOLIZATION Case report
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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change
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作者 ZHAO Xuqin LUO Min +3 位作者 MENG Fanhao SA Chula BAO Shanhu BAO Yuhai 《Journal of Arid Land》 SCIE CSCD 2024年第1期46-70,共25页
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation... Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas. 展开更多
关键词 gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau
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一个高效求解含时Gross-Pitaevskii方程的算法
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作者 舒丽莎 董光炯 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期84-90,共7页
Gross-Pitaevskii方程广泛应用于玻色-爱因斯坦凝聚体(Bose-Einstein condensate,BEC)的动力学研究,然而这个方程通常很难解析求解.因此发展相应的高精度数值求解方法非常重要.发展了结合算符劈裂法、Crank-Nicolson算法和四阶精度Nume... Gross-Pitaevskii方程广泛应用于玻色-爱因斯坦凝聚体(Bose-Einstein condensate,BEC)的动力学研究,然而这个方程通常很难解析求解.因此发展相应的高精度数值求解方法非常重要.发展了结合算符劈裂法、Crank-Nicolson算法和四阶精度Numerov算法的高效求解Gross-Pitaevskii方程的新数值计算方法.通过数值计算可以表明,与传统的四阶精度的五点差分法相比,所提出的算法具有高效和消耗内存小的优点. 展开更多
关键词 gross-PITAEVSKII方程 算符劈裂法 Crank-Nicolson算法 Numerov算法
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数值求解耦合Gross-Pitaevskii方程组基态解的离散归一化梯度流方法
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作者 赵子尧 马强 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期9-14,共6页
本文提出了一种求解磁场项为常数的耦合Gross-Pitaevskii方程组基态解的数值方法.基于单组分近似理论,本文将方程组的能量函数等价为单组分的能量泛函,然后基于降阶后的能量表达式提出了离散归一化梯度流数值方法.数值算例表明,该方法... 本文提出了一种求解磁场项为常数的耦合Gross-Pitaevskii方程组基态解的数值方法.基于单组分近似理论,本文将方程组的能量函数等价为单组分的能量泛函,然后基于降阶后的能量表达式提出了离散归一化梯度流数值方法.数值算例表明,该方法高效且可靠. 展开更多
关键词 耦合gross-Pitaevskii方程组 基态解 单组分近似 归一化梯度流
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Public Effective Dose Assessment Using Gross Alpha and Beta Radioactivity Levels of Tap Drinking Water in the District of Abidjan, Cote d’Ivoire
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作者 Ponaho Claude Kezo Issa Konate Tekpo Paul Dali 《Journal of Environmental Protection》 CAS 2023年第3期127-138,共12页
In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Bet... In order to assess public effective dose due to gross alpha and beta in water, 43 tap water samples were collected from different areas in the District of Abidjan. Using the low background Gas-less Automatic Alpha/Beta counting system (Canberra iMatic<sup>TM</sup>) for analysis, the gross alpha and beta concentrations found varied from 0.001 ± 0.002 to 0.063 ± 0.050 Bq/l with an average of 0.013 ± 0.012 Bq/l and from 0.067 ± 0.080 to 0.320 ± 0.120 Bq/l with an average of 0.174 ± 0.076 Bq/l, respectively in samples. The public effective dose assessment showed values of dose to ingestion of alpha and beta emitter radionuclides lower than the recommended value of dose for drinking water 0.1 mSv/y, except in 30% of the samples. These results show the need for additional studies to be conducted in order to clarify the hazardousness of these water samples. However, this study still remains important because it has provided necessary data for future tap water quality monitoring studies in the District of Abidjan. 展开更多
关键词 gross Alpha and Beta Concentration Tap Water Effective Dose District of Abidjan
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Interrupted Time Series Analysis of Military and Civilian Regimes in Nigeria: A Statistical Evidence from Gross Domestic Product (GDP)
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作者 Desmond Chekwube Bartholomew Geoffrey Uzodinma Ugwuanyim +1 位作者 Ukamaka Cynthia Orumie Francis Attah Egwumah 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期635-660,共26页
Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources... Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources are used in the economy. Higher taxes, fees, and greater regulations can stymie businesses or entire industries and the resulting impact is reflected on the country’s economy status (strong or weak). The growth rate of GDP is often used as an indicator of the general health of the economy. In broad terms, an increase in real GDP is interpreted as a sign that the economy is doing well. So it is important to study and pay more attention to country’s GDP growth rate. In this paper, an intervention analysis approach was applied to Nigeria GDP data in order to evaluate the performances of military and civilian rules in the country. Data on Nigeria GDP were collected and subjected to interrupted (intervention) time series model. Based on the Alkaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and sigma<sup>2</sup> values, the interrupted time series model ARIMA (1, 1, 0) with exogenous variables (per capita per capita GDP, intervention, year and yearAfter) was identified as the best model amongst other competing models. It was observed that the intervention (civilian rule) was significant at the 10% level of significance in increasing the Nigeria GDP by 10B US$ on the average since 2005 till 2021 while controlling for the effects of other determinants. Also, the ARIMA (1, 1, 0) forecasts indicate that the Nigeria GDP will continue increasing during the civilian rule. As a result, changing from military rule to civilian rule in Nigeria significantly increased the GDP of the country. 展开更多
关键词 ARIMA FORECAST gross Domestic Product NIGERIA INTERVENTION Interrupted Time Series
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Interrupted Time Series Analysis of Military and Civilian Regimes in Nigeria: A Statistical Evidence from Gross Domestic Product (GDP)
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作者 Desmond Chekwube Bartholomew Geoffrey Uzodinma Ugwuanyim +1 位作者 Ukamaka Cynthia Orumie Francis Attah Egwumah 《Open Journal of Statistics》 2023年第4期635-660,共26页
Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources... Governments influence the economy by changing the level and types of taxes, the extent and composition of spending, and the degree and form of borrowing. Governments directly and indirectly influence the way resources are used in the economy. Higher taxes, fees, and greater regulations can stymie businesses or entire industries and the resulting impact is reflected on the country’s economy status (strong or weak). The growth rate of GDP is often used as an indicator of the general health of the economy. In broad terms, an increase in real GDP is interpreted as a sign that the economy is doing well. So it is important to study and pay more attention to country’s GDP growth rate. In this paper, an intervention analysis approach was applied to Nigeria GDP data in order to evaluate the performances of military and civilian rules in the country. Data on Nigeria GDP were collected and subjected to interrupted (intervention) time series model. Based on the Alkaike Information Criterion (AIC), Bayesian Information Criterion (BIC) and sigma<sup>2</sup> values, the interrupted time series model ARIMA (1, 1, 0) with exogenous variables (per capita per capita GDP, intervention, year and yearAfter) was identified as the best model amongst other competing models. It was observed that the intervention (civilian rule) was significant at the 10% level of significance in increasing the Nigeria GDP by 10B US$ on the average since 2005 till 2021 while controlling for the effects of other determinants. Also, the ARIMA (1, 1, 0) forecasts indicate that the Nigeria GDP will continue increasing during the civilian rule. As a result, changing from military rule to civilian rule in Nigeria significantly increased the GDP of the country. 展开更多
关键词 ARIMA FORECAST gross Domestic Product NIGERIA INTERVENTION Interrupted Time Series
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两地无花果微量元素及总放射性物质分析与质量评估
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作者 谢超 程晓宏 +2 位作者 赵坚 杨娟 张萍 《化学工程师》 CAS 2024年第3期19-22,共4页
目的评估新疆阿图什与江苏南通两地无花果产品质量。方法运用电感耦合等离子体质谱仪和总放测量仪,分别对新疆阿图什和江苏南通两地无花果微量元素和总放射性物质进行分析检测。结果新疆阿图什无花果与江苏南通本地无花果微量元素相比,... 目的评估新疆阿图什与江苏南通两地无花果产品质量。方法运用电感耦合等离子体质谱仪和总放测量仪,分别对新疆阿图什和江苏南通两地无花果微量元素和总放射性物质进行分析检测。结果新疆阿图什无花果与江苏南通本地无花果微量元素相比,铝、钾、钙、钒、锰、钴、镍、铜、锌、硒、钡等11种微量元素含量明显较高,镁和钼元素略低,铬元素较低。两地无花果的总α放射性物质和总β放射性物质均合格。结论新疆阿图什无花果产品质量优于江苏南通本地的无花果,具有较高的产品开发价值。 展开更多
关键词 无花果 电感耦合等离子体质谱法 比较测量法 总α放射性 总Β放射性
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耦合Gross-Pitaevskii方程的高效保质量守恒格式
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作者 李羽 孔令华 罗奕杨 《江西师范大学学报(自然科学版)》 CAS 北大核心 2023年第2期194-198,共5页
该文为耦合Gross-Pitaevskii方程提出了一个新的保质量守恒格式.首先对空间导数利用高阶紧致格式离散得到半离散格式;然后在时间方向上利用基于外推的Crank-Nicolson格式离散,得到一个半显式的数值格式,然而此格式不能保持GP方程固有的... 该文为耦合Gross-Pitaevskii方程提出了一个新的保质量守恒格式.首先对空间导数利用高阶紧致格式离散得到半离散格式;然后在时间方向上利用基于外推的Crank-Nicolson格式离散,得到一个半显式的数值格式,然而此格式不能保持GP方程固有的质量守恒,因此,对格式得到的数值解利用投影方法进行修正,使其满足离散质量守恒;最后通过数值实验验证了该格式具有高精度以及保持质量守恒. 展开更多
关键词 耦合gross-Pitaevskii方程 投影法 高阶紧致格式 质量守恒
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一类带旋转的Gross-Pitaevskii方程
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作者 陈咨宇 张健 《四川师范大学学报(自然科学版)》 CAS 2023年第6期741-747,共7页
研究带旋转的Gross-Pitaevskii方程的柯西问题.该模型模拟在旋转磁陷阱下的玻色-爱因斯坦凝聚,描述在限制陷阱中旋转多体玻色子的平均场动力学.主要通过使用经典非线性数量场方程的变分特征和方程相关守恒律,依赖于基态的存在性和Viria... 研究带旋转的Gross-Pitaevskii方程的柯西问题.该模型模拟在旋转磁陷阱下的玻色-爱因斯坦凝聚,描述在限制陷阱中旋转多体玻色子的平均场动力学.主要通过使用经典非线性数量场方程的变分特征和方程相关守恒律,依赖于基态的存在性和Virial等式,从而得到爆破解的充分条件. 展开更多
关键词 非线性薛定谔方程 gross-PITAEVSKII方程 角动量 部分限制 爆破解
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基于体外仿生酶水解物能值和化学成分预测谷物饲料原料的鸡代谢能值
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作者 李凯 白国松 +4 位作者 滕春然 马腾 钟儒清 陈亮 张宏福 《中国农业科学》 CAS CSCD 北大核心 2024年第10期2035-2045,共11页
【目的】利用单胃仿生消化系统测定小麦、稻谷及糙米原料的鸡酶水解物能值(EHGE),结合两种体内法(自由采食法(FF)和排空强饲法(TF))测定的小麦、稻谷及糙米原料的鸡代谢能值,建立基于酶水解物能值和原料化学成分的鸡代谢能值预测模型,... 【目的】利用单胃仿生消化系统测定小麦、稻谷及糙米原料的鸡酶水解物能值(EHGE),结合两种体内法(自由采食法(FF)和排空强饲法(TF))测定的小麦、稻谷及糙米原料的鸡代谢能值,建立基于酶水解物能值和原料化学成分的鸡代谢能值预测模型,为谷物原料鸡代谢能值快速预测提供参考。【方法】使用单胃仿生消化系统分别测定3种来源的小麦、稻谷及糙米共计9个样品的鸡酶水解物能值(EHGE),每个谷物样品设置5个重复,每个重复1根消化管。结合前期通过自由采食法和排空强饲法测定的同批次原料的鸡表观代谢能值(AME)和真代谢能值(TME),利用线性回归建立基于化学成分及酶水解物能值的AME、TME预测模型。【结果】(1)在干物质基础下,3种来源的小麦原料酶水解物能值分别为14.46、14.63和14.80 MJ·kg^(-1);3种来源的稻谷原料酶水解物能值分别为12.52、13.59和13.40 MJ·kg^(-1);3种来源的糙米原料酶水解物能值分别为14.74、15.10和15.23 MJ·kg^(-1)。(2)粗灰分和中性洗涤纤维分别与FF法测定的AME和TME(AME_(FF),TME_(FF))和TF法测定的AME和TME(AME_(TF),TME_(TF))呈极显著的负相关(P<0.01);EHGE与AME_(FF)、AME_(TF)、TME_(FF)、TME_(TF)均呈极显著正相关关系(P<0.01),相关系数分别为0.801、0.864、0.807和0.866。(3)相较于EHGE建立的代谢能预测模型,基于化学成分建立的预测模型有更高的决定系数(R2)、更低的残差标准差(RSD)。对于AME_(FF)和TME_(FF),Ash为最佳预测因子,预测模型为:AME_(FF)=16.728-0.842×Ash(R^(2)=0.809,RSD=0.826,P=0.001),TME_(FF)=16.812-0.842×Ash(R^(2)=0.816,RSD=0.806,P=0.001);对于AME_(TF)和TME_(TF),NDF为最佳预测因子,预测模型分别为:AME_(TF)=16.106-0.157×NDF(R^(2)=0.907,RSD=0.523,P<0.001),TME_(TF)=17.654-0.157×NDF(R^(2)=0.903,RSD=0.534,P<0.001)。【结论】小麦、和糙米的EHGE高于稻谷EHGE,且三类谷物原料的EHGE与体内法测定的代谢能值具有较好的相关性。本研究条件下,基于化学成分建立的谷物AME和TME预测模型优于基于EHGE建立的预测模型。 展开更多
关键词 代谢能 酶水解物能值 预测模型 谷物
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饲用油脂总能测定条件优化研究
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作者 唐桂芬 王金荣 +4 位作者 刘昆 赵雪峰 许亚楠 王昊 张卫宪 《饲料工业》 CAS 北大核心 2024年第9期101-106,共6页
试验选用氧弹量热法进行饲用油脂总能测定条件优化研究。选用豆油、调和油作为试验材料,研究是否添加基质对总能测定结果的影响,进行检测方法优化;选用11种油脂作为试验材料,验证不同试样质量(0.4、0.6、0.8、1.0、1.2 g)对测定结果的影... 试验选用氧弹量热法进行饲用油脂总能测定条件优化研究。选用豆油、调和油作为试验材料,研究是否添加基质对总能测定结果的影响,进行检测方法优化;选用11种油脂作为试验材料,验证不同试样质量(0.4、0.6、0.8、1.0、1.2 g)对测定结果的影响;选用5种油脂作为试验材料,比对不同仪器对测定结果的影响。结果表明:测定豆油总能,添加基质后测定结果变异系数大,重复性差(P<0.05),不添加基质重复性好(P>0.05);不添加基质方法进行日内、日间试验,测定结果差异不显著(P>0.05),测定结果稳定性好(P<0.05)。不同试样质量对豆油、调和油、椰子油、月桂酸、鱼油、鸡油1#、鸡油2#、猪油1#、猪油2#等9种油脂总能测定结果差异不显著(P>0.05),对棕榈油总能测定结果表现为差异显著(P<0.05),对磷脂总能测定结果表现为差异极显著(P<0.001),试样质量适宜范围为0.6~0.8 g。两种氧弹量热仪测定椰子油、棕榈油、豆油、月桂酸、磷脂5种油脂相同试样质量,测定总能结果差异不显著(P>0.05)。本试验条件下,油脂测定试验无需添加基质,该方法测定总能结果稳定、重复性好。不同试样质量对豆油、调和油、椰子油、月桂酸、鱼油、鸡油1#、鸡油2#、猪油1#、猪油2#等9种油脂表现为差异不显著,适宜试样质量为0.4~1.0 g;对棕榈油表现为差异显著,适宜试样质量为0.6~1.0 g;对磷脂表现为差异极显著,适宜试样质量为0.8~1.0 g。用两种氧弹量热仪测定油脂总能结果无明显差异。 展开更多
关键词 饲用油脂 总能 氧弹量热仪 样品质量 基质
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黄河流域植被总初级生产力对持续性干旱水分亏缺的响应
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作者 薛联青 王文壮 +2 位作者 刘远洪 韩强 杨明杰 《水资源保护》 EI CAS CSCD 北大核心 2024年第3期44-51,共8页
利用植被总初级生产力和高精度分层土壤含水量数据分析了2001—2020年黄河流域生长季总初级生产力时空分布和变化特征,量化了流域不同深度土壤湿度之间的相关关系,探究了不同植被类型在生长季的总初级生产力对土壤连续水分亏缺事件的响... 利用植被总初级生产力和高精度分层土壤含水量数据分析了2001—2020年黄河流域生长季总初级生产力时空分布和变化特征,量化了流域不同深度土壤湿度之间的相关关系,探究了不同植被类型在生长季的总初级生产力对土壤连续水分亏缺事件的响应关系。结果表明:黄河流域总初级生产力空间上呈东高西低、南高北低的分布特征,生长季耕地累积总初级生产力最大、林地次之、草地最小,研究期内流域总初级生产力整体呈上升趋势,耕地相对增速最大、草地次之、林地最小;流域土壤湿度在空间和时间上均有显著差异,表层土壤含水量波动对深层土壤含水量的影响随深度增加而减小,林地和耕地表层与深层土壤含水量的相关性远高于草地;流域草地和耕地总初级生产力对土壤水分的深度敏感区间为0~40 cm,林地的深度敏感区间为0~100 cm,在深度敏感区间内,随着土壤连续水分亏缺天数的增加,草地和耕地总初级生产力依次经历短暂平稳、加速下降、降速趋缓的变化过程,而林地总初级生产力则表现出短暂下挫、长时间平稳、加速下降的变化特征。 展开更多
关键词 总初级生产力 土壤含水量 持续性干旱 水分亏缺 黄河流域
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自动确定边角混合网独立闭合差的增量算法
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作者 宋占峰 李荣之 李军 《中国铁道科学》 EI CAS CSCD 北大核心 2024年第3期78-86,共9页
为评定外业观测数据质量和发现粗差,提出了一种闭合差搜索的通用算法。首先,针对高速铁路隧道中的各类边角混合网,基于平差理论,计算由边角混合网中测站数、非测站数和观测数确定其独立闭合差的数目,给出最简闭合差构成原则,求出余弦和... 为评定外业观测数据质量和发现粗差,提出了一种闭合差搜索的通用算法。首先,针对高速铁路隧道中的各类边角混合网,基于平差理论,计算由边角混合网中测站数、非测站数和观测数确定其独立闭合差的数目,给出最简闭合差构成原则,求出余弦和正弦闭合差,推导闭合差限差计算模型,建立由闭合差探测观测值粗差的方法;进而导出闭合差增量与测站递增产生的重叠观测点数之间的数学关系式,设计数据结构实现测站与结点间双向多对多的拓扑映射关系,并基于分治思想,提出队列-测站双循环的增量算法来自动搜索最简且独立的闭合差;最后,以西南某高速铁路隧道构建的边角混合网为例进行算法验证。结果表明:增量算法能够在混合网中自动确定100%数量的最简独立闭合差,对观测值中存在的粗差100%予以探测,验证了采用该算法搜索闭合差及检核粗差的有效性。 展开更多
关键词 高速铁路长大隧道 闭合差 边角混合网 增量算法 粗差探测
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我国生态产品总值统计核算问题研究
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作者 周先东 任雪 +1 位作者 顾若琳 潘杨 《中国国土资源经济》 2024年第4期43-52,共10页
文章在分析GEP概念内涵、分类与核算方法相关研究的基础上,充分借鉴国际统计核算的经验,结合我国GEP统计核算实践,从通用性和可操作性出发,建立了一套与自然资源部门土地利用现状分类相匹配、符合我国实际的GEP核算分类标准,重新划分了... 文章在分析GEP概念内涵、分类与核算方法相关研究的基础上,充分借鉴国际统计核算的经验,结合我国GEP统计核算实践,从通用性和可操作性出发,建立了一套与自然资源部门土地利用现状分类相匹配、符合我国实际的GEP核算分类标准,重新划分了森林、草地、湿地、农田、城市、荒漠、海洋等生态系统的分类范围。同时,基于GEP概念、特征、逻辑准则,提出了我国生态产品清单筛选的五个基本原则,讨论了现有GEP实物量和价值量核算方法存在的不足,指出了核算方法选取时需注意把握的问题及未来改进方向。 展开更多
关键词 生态产品总值(GEP) 概念内涵 行业分类 核算方法 基本原则
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高速铁路三维控制网粗差实时判别方法研究
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作者 曹娟华 秦航 吴维军 《铁道勘察》 2024年第3期15-20,27,共7页
高速铁路三维控制网外业观测易受不利环境因素影响,难免存在测量粗差,为了尽早识别测量粗差,提高外业数据质量及后续平差结果的精度,需进行三维控制网粗差实时判别方法的研究。根据三维控制网网形及其特点,详细分析三维控制网闭合环的类... 高速铁路三维控制网外业观测易受不利环境因素影响,难免存在测量粗差,为了尽早识别测量粗差,提高外业数据质量及后续平差结果的精度,需进行三维控制网粗差实时判别方法的研究。根据三维控制网网形及其特点,详细分析三维控制网闭合环的类型,采用三维控制网(Ⅰ类、Ⅱ类、Ⅲ类)22种闭合环进行闭合差计算;同时,基于协方差传播定律构建闭合环校核边中误差的数学模型,以2倍闭合环相对中误差为限差,判别三维控制网外业数据质量。研究表明,三维控制网网形具有较强的规律性和对称性,在完成归整后,可使用1/7000,1/13000和1/23000为对应闭合环的极限误差进行粗差判别。研究结果表明,在三维控制网外业数据观测过程中,采用该方法能够实时判别并发现测量粗差,有利于以最小代价进行现场补测,从而提高三维控制网数据可靠性和数据质量。 展开更多
关键词 高速铁路 三维控制网 粗差判别 协方差 闭合差
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