Spatial Heterogeneity of Embedded Water Consumption from the Perspective of Virtual Water Surplus and Deficit in the Yellow River Basin,China

Virtual water trade(VWT)provides a new perspective for alleviating water crisis and has thus attracted widespread attention.However,the heterogeneity of virtual water trade inside and outside the river basin and its influencing factors remains further study.In this study,for better investigating the pattern and heterogeneity of virtual water trade inside and outside provincial regions along the Yellow River Basin in 2015 using the input-output model(MRIO),we proposed two new concepts,i.e.,virtual water surplus and virtual water deficit,and then used the Logarithmic Mean Divisia Index(LMDI)model to identify the inherent mechanism of the imbalance of virtual water trade between provincial regions along the Yellow River Basin and the other four regions in China.The results show that:1)in provincial regions along the Yellow River Basin,the less developed the economy was,the larger the contribution of the agricultural sector in virtual water trade,while the smaller the contribution of the industrial sector.2)Due to the large output of agricultural products,the upstream and midstream provincial regions of the Yellow River Basin had a virtual water surplus,with a net outflow of virtual water of 2.7×10^(8) m^(3) and 0.9×10^(8) m^(3),respectively.3)provincial regions along the Yellow River Basin were in a virtual water deficit with the rest of China,and the decisive factor was the active degree of trade with the outside.This study would be beneficial to illuminate the trade-related water use issues in provincial regions along the Yellow River Basin,which has farreaching practical signific-ance for alleviating water scarcity.

Performance of the walking trail making test in older adults with white matter hyperintensities

BACKGROUND Several studies have reported that the walking trail making test(WTMT)completion time is significantly higher in patients with developmental coordination disorders and mild cognitive impairments.We hypothesized that WTMT performance would be altered in older adults with white matter hyperintensities(WMH).AIM To explore the performance in the WTMT in older people with WMH.METHODS In this single-center,observational study,25 elderly WMH patients admitted to our hospital from June 2019 to June 2020 served as the WMH group and 20 participants matched for age,gender,and educational level who were undergoing physical examination in our hospital during the same period served as the control group.The participants completed the WTMT-A and WTMT-B to obtain their gait parameters,including WTMT-A completion time,WTMT-B completion time,speed,step length,cadence,and stance phase percent.White matter lesions were scored according to the Fazekas scale.Multiple neuropsychological assessments were carried out to assess cognitive function.The relationships between WTMT performance and cognition and motion in elderly patients with WMH were analyzed by partial Pearson correlation analysis.RESULTS Patients with WMH performed significantly worse on the choice reaction test(CRT)(0.51±0.09 s vs 0.44±0.06 s,P=0.007),verbal fluency test(VFT,14.2±2.75 vs 16.65±3.54,P=0.012),and digit symbol substitution test(16.00±2.75 vs 18.40±3.27,P=0.010)than participants in the control group.The WMH group also required significantly more time to complete the WTMT-A(93.00±10.76 s vs 70.55±11.28 s,P<0.001)and WTMT-B(109.72±12.26 s vs 82.85±7.90 s,P<0.001).WTMT-A completion time was positively correlated with CRT time(r=0.460,P=0.001),while WTMT-B completion time was negatively correlated with VFT(r=-0.391,P=0.008).On the WTMT-A,only speed was found to statistically differ between the WMH and control groups(0.803±0.096 vs 0.975±0.050 m/s,P<0.001),whereas on the WTMT-B,the WMH group exhibited a significantly lower speed(0.778±0.111 vs 0.970±0.053 m/s,P<0.001)and cadence(82.600±4.140 vs 85.500±5.020 steps/m,P=0.039),as well as a higher stance phase percentage(65.061±1.813%vs 63.513±2.465%,P=0.019)relative to controls.CONCLUSION Older adults with WMH showed obviously poorer WTMT performance.WTMT could be a potential indicator for cognitive and motor deficits in patients with WMH.

Field water surplus and deficit of major crops in dryland of northern China

The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data in 1950-1980, mean field water surplus or deficit on climatic, crop and cropland basis in dryland of northern China was calculated, and the pattern of field water surplus or deficit was analyzed and discussed in this paper.

The fate of surplus embryos in the setting of assisted reproductive technology:A scoping review

Objective:To identify the attitudes of infertile couples toward their surplus frozen embryos.Methods:This study was according to PRISMA-ScR as the guideline for scoping review.Studies that assessed the attitudes of patients or infertile couples who had surplus embryos were included.We conducted systematic searches in English studies from April 2011-April 2021 using 7 databases:PubMed,Science Direct,EBSCO,Scopus,the Cochrane Library,Sage Journals,and Google Scholar.Data were charted based on author,year of publication,country,purpose,data collection,key findings,and research focus/domain.Results:A total of 37 research articles were included in the analysis.Their attitudes encompassed:supporting the donation of the surplus embryos for both research and reproductive purposes,continuing to store the frozen embryos,and disposing of the surplus embryos.Conclusions:Most of the infertile patients support donating their surplus embryos for research and reproductive purposes.

基于人机协同决策的运输调度优化研究

为求解带柔性约束的运输调度问题,本文提出一个基于逆差函数的人机协同决策方法。该方法主要包括两个阶段,第1阶段,借助数学规划模型,利用计算机的强大计算能力,快速求解得到问题的一个可行解;第2阶段,借助逆差函数模型,利用人类自身的知识与经验,在考虑柔性约束的情形下,进一步优化第1阶段的可行解。两个阶段通过逆差函数图像构成的图形用户界面进行实时交互,实现人机协同决策。通过网约定制公交车辆调度和民航飞机调度两个案例问题的求解,验证基于逆差函数的人机协同决策方法的有效性。计算结果表明:该方法可实现车次链/航班链的自动化构建和空驶车次的自动化插入,有助于求解带有复杂柔性约束的运输调度问题。

秘鲁亏损弥补和篱笆圈规定对油气投资项目纳税及经济效益影响分析

资源国有关亏损弥补和篱笆圈财税条款会影响油气投资项目纳税及经济效益。秘鲁国家财税制度的特别之处主要在于规定了两种亏损弥补方式,且同一公司持有的不同油气区块间不存在篱笆圈,这两条规定的结合为石油公司在秘鲁开展税收筹划以减少纳税、提高油气项目经济效益提供了空间。通过情景假设和模型测算,证明秘鲁的同一油气区块在不同税前利润情景下选择合适的亏损弥补方式可以减少纳税和提高项目经济效益。当石油公司在秘鲁获取两个以上区块时,通过提前统筹谋划区块的获取顺序和投产时间等,可以充分利用区块间合并纳税的优惠政策提高整体投资效益。在进行秘鲁油气项目投资组合评价时,应重视亏损弥补方式的选择和区块间合并纳税的影响。

THE RISK MODEL OF THE EXPECTED DISCOUNTED PENALTY FUNCTION WITH CONSTANT INTEREST FORCE

In this article, the expected discounted penalty function Фδ,α （u） with constant interest δ and ＂discounted factor＂ exp（-αTδ） is considered. As a result, the integral equation of Фδ,α （u） is derived and an exact solution for Фδ,α （0） is found. The relation between the joint density of the surplus immediately prior to ruin, and the deficit at ruin and the density of the surplus immediately prior to ruin is then obtained based on analytical methods.

The dividend function in the jump-diffusion dual model withbarrier dividend strategy

A dual model of the perturbed classical compound Poisson risk model is considered under a constant dividend barrier. A new method is used in deriving the boundary condition of the equation for the expectation function by studying the local time of a related process. We obtain the expression for the expected discount dividend function in terms of those in the corresponding perturbed compound Poisson risk model without barriers. A special case in which the gain size is phase-type distributed is illustrated. We also consider the existence of the optimal dividend level.

A Joint Density Function in the Renewal Risk Model

In this paper, we consider a general expression for Ф（u, x, y）, the joint density function of the surplus prior to ruin and the deficit at ruin when the initial surplus is u. In the renewal risk model, this density function is expressed in terms of the corresponding density function when the initial surplus is O. In the compound Poisson risk process with phase-type claim size, we derive an explicit expression for Ф（u, x, y）. Finally, we give a numerical example to illustrate the application of these results.

Joint Distribution for the Risk Process with Premiums Depending on the Current Reserve

With the ever-evolving of modern risk theory,more and more attention should be paid to the modification of the classical risk theory. In this paper a risk process with premiums dependent on the current reserve is considered. An explicit expression for the joint distribution of the time of ruin,the surplus immediately before ruin and the deficit at ruin is derived. Finally,some important actuarial diagnostics including the ultimate ruin probability is investigated.

Ecological Carrying Capacity of Cities in Southwest China Against the Background of Rapid Urbanization: A Case Study of Mianyang, Sichuan, China

As Mianyang has neglected the coordination relationship with the ecological environment in the course of rapid urbanization,its ecological environment is getting worse.To this end,this study used the ecological footprint method to explore the ecological carrying capacity of Mianyang from 2007 to 2014 under the background of rapid urbanization,which has important guiding significance for the future development of Mianyang.The results showed that in 2007–2014,the ecological footprint of Mianyang was greater than its ecological carrying capacity,indicating that Mianyang is in an ecological deficit.Specifically,the per capita ecological footprint showed a downtrend,and the per capita ecological carrying capacity showed a trend of smooth decline.In addition,the per capita ecological deficit was generally decreasing.In summary,Mianyang was generally in an ecological deficit in 2007–2014.Thus,the ecological environment of the region should be protected,in order to promote the sustainable development of the ecosystem in the region.

Root Causes of China’s Trade Surplus and How to Balance It

This paper explains the root cause of China＇s trade surplus and argues that it is rooted in structural factors. China＇s dual economic structure and the relatively slow growth in wages due to the abundant supply of labor have led to a large supply glut between China＇s domestic demand and output, which has been balanced by export. This is a structural problem that cannot be solved by currency appreciation or the readjustment of capital account deficits. A potentially viable option is to adjust the current account by developing a new opening-up system featuring more freedom and compliance.

A Simplified Concept to Test Erosion or Sedimentation Potential along a Tidal River in the Ganges-Brahmaputra-Meghna Delta

The Payra is a tidal river with meandering planform in which around 6.5 km long landmass is formed naturally during the last 40 years that is selected for an establishment by the Government of Bangladesh. However, the site experiences intermittent erosion at several locations and poses threat to the newly developed infrastructures. In the present study, a Rouse type simple model is used to estimate the equilibrium profiles of suspended sediment concentration below which the system is likely to be eroded and regarded as “Sediment Deficit System, SDS” and above which the system is likely to be sedimented and regarded as “Sediment Surplus System, SSS”. The model was then tested at the study reach using the measured flow-sediment data complemented by field observation and Landsat images-based planform analysis. The analysis revealed that the residual flow-sediment regime in the study site is representing the “sediment deficit system” that causes continuous threat for erosion throughout the tidal cycles. Therefore, the availability of new landmass should not be the only criterion for the quick selection of a project site, and residual flow-sediment regime needs to consider as an additional parameter for such decision-making process.

Decision Making in Children with Attention-Deficit/Hyperactivity Disorder

Background: Informed consent forms and clinical study participation explanations contain many specialized words including medical terms that are difficult to understand. The difficulty is particularly obvious for children with developmental disorders who show attention or similar problems. This study quantitatively evaluated the decision-making ability of these children using the Wechsler Intelligence Scale for Children-III (WISC-III) as a preliminary study for a multi-faceted investigation that would also use physiological indices. Methods: Participants were 11 children with Attention Deficit/Hyperactivity Disorder (AD/HD). The WISC-III was used for quantitative evaluation of their decision-making ability. Results of intelligence quotients (IQs), group indices, and subtest scores were analyzed. Results: The mean Performance IQ was four points lower than the mean Verbal IQ. The mean score for the Processing Speed index was lower by more than one standard deviation (SD). The mean scores for the Coding and Object Assembly subtests were lower by more than two SDs. Conclusion: The WISC-III results for IQ and group indices suggested the efficacy of auditory explanations. In addition, the subtest results suggested the necessity to pay sufficient attention to risk-benefit weighting in explanations. These findings suggested that the decision-making ability of children with AD/HD could be assessed using the WISC-III.

基于通径分析原理的冬小麦缺水诊断指标敏感性分析

根据冬小麦田间试验结果,用通径分析的方法,把不同灌溉决策指标对干物质和叶片水分利用效率(WUE)的影响进行了分析。通过土壤水分含量、叶面蒸腾、光合有效辐射、光合作用速率、气孔导度和叶温对作物干物质产量的通径分析发现,影响干物质产量最大的是叶面蒸腾,其次是光合有效辐射和叶温。通过充分灌溉和干旱水分处理相应时刻太阳辐射、光合有效辐射、空气水汽压差、气孔导度和叶温对作物叶片WUE的通径分析发现,对于适宜水分处理来说,主要影响WUE因子不是上述5个指标,而是土壤水分状况起到决定因素;对于干旱处理来说,主要影响因子是光合有效辐射和叶面温度。通过对干物质通径分析自变量指标的增减对结果的影响分析,发现,在考虑干物质生产和作物水分利用效率最优的目标时,灌溉决策指标要注意叶面蒸腾、光合有效辐射、叶面温度和土壤水分的变化。

成瘾人群的决策障碍：研究范式与神经机制

药物成瘾者和赌博成瘾者常常偏好即刻的奖赏而忽视将来的消极结果。在进行决策任务时,他们倾向于做出不利的选择,偏好短时的获益而不顾长期的损失,这是一种决策障碍的表现。延迟折扣任务(DDT)、爱荷华赌博任务(IGT)和剑桥赌博任务(CGT)是研究决策障碍的三种常用方法和范式,分别考察成瘾人群的冲动性决策、决策短视和决策时的冒险行为。近十几年来的研究表明,前额叶皮层(PFC)在人类的决策活动中起重要作用。其中,腹内侧前额叶(VMPFC)、眶额叶(OFC)、背外侧前额叶(DLPFC)等皮层的功能变化与成瘾人群的决策障碍有密切关系。

海洛因成瘾患者眶额叶皮层功能连接异常与决策能力缺失的关系

目的探讨慢性海洛因成瘾者眶额叶皮层(OFC)功能连接的变化及其与慢性海洛因成瘾者冲动性决策行为的关系。方法慢性海洛因成瘾男性患者14例,与之年龄、受教育程度和尼古丁依赖水平匹配的健康被试14例参加本研究。采用1.5 T磁共振扫描仪,16通道神经血管线圈,对被试分别进行头颅结构和静息态功能磁共振扫描,后利用SPM8软件以双侧眶额叶皮层为感兴趣区,分别进行组内和组间眶额叶皮层静息态功能网络分析。采用爱荷华赌博任务(IGT)对两组被试进行决策能力评估。结果与对照组比较,慢性海洛因成瘾组眶额叶皮层与右侧顶下小叶(rIPL)之间功能连接显著下降(t=3.5,P<0.05,多重比较校正)。IGT的行为学结果发现,随决策次数递增,两组被试的净分数均逐渐提高(P<0.001),但正常对照组的净分数明显高于海洛因成瘾组(P<0.001)。海洛因成瘾患者OFC-rIPL功能连接与IGT评分呈明显负相关性(r=-0.550,P=0.041)。结论慢性海洛因成瘾者OFC-rIPL脑网络存在异常,而这种异常可能是其在行为学上存在冲动性决策障碍的神经基础,也可能是其成瘾行为的产生、维持和复吸的原因之一。

都江堰灌区水资源优化调度系统研究

针对都江堰农业灌区覆盖面广,各区域灌溉农时略有差异和具备二级配水管理机构的特点,在非充分灌溉和大系统理论基础上,提出了基于时空优化的农业用水优化调度模型以及多目标用水群决策支持机制,构建了适合都江堰灌区的水资源优化调度系统框架,并重点研究了优化模型并初步探讨了群决策机制的实现方法.该系统可实施性强,部分研究结果应用于都江堰灌区渠首6条干渠配水系统,经过近一年的运行,取得了良好的效果.

非充分灌溉下精量灌溉决策方法研究

针对我国干旱半干旱地区节水灌溉中需要动态调节的问题,提出在灌溉决策中考虑非充分灌溉因素,运用Jensen乘法模型建立"灌水-收益"的数学模型,采用遗传算法、基于SQP算法和基于有效集算法的fmincon函数求解模型,以宝鸡峡灌区冬小麦为例,验证所建模型的准确性及求解方法的可行性,对比计算结果发现,基于SQP算法的fmincon函数运算结果最优,相对遗传算法其灌溉收益提高3%,运行时间降低60%,稳定性优异,并使用该算法进行了非充分优化灌溉下的决策系统设计。

关于我国农产品贸易逆差问题的系统分析

2004年我国农产品进出口贸易呈现重要转折,从农业净出口国转变为农业净进口国。本文运用系统分析的方法,在分析我国农产品贸易形势,剖析我国农产品贸易复杂的国内、国际环境基础上,提出以促进现代农业的建设、农村经济的发展以及农民收入的提高为总体目标,以突破贸易壁垒和国际农产品贸易的复杂环境,提升我国农产品的国际竞争力、开拓国际市场为目的,从具体操作到战术再到战略的层次递进的决策组织系统。