Spatial Agglomeration and Diffusion of Population Based on a Regional Density Function Approach:A Case Study of Shandong Province in China

Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,China,but few have applied regional density functions to the analysis.Therefore,based on the 2000,2010,and 2020 population censuses,this study used monocentric and polycentric regional density functions to study the characteristics of population agglomeration and diffusion in Shandong.This is followed by an in-depth discussion based on population growth rate data and hot-and cold-spot analyses.The results showed that the Shandong Province population was spatially unevenly distributed.Population growth rates were higher in urban centers and counties,with more significant changes in population size in the eastern coastal areas than in the inland areas.As verified in this study,the logarithmic form of the single-center regional density function R2 was greater than 0.8,which was in line with the population spatial structure of Shandong Province.During the study period,the estimated population density of the regional center and the absolute value of the regional population density gradient both increased,indicating a clear and increasing trend of centripetal agglomeration of regional centers over the study period.Overall,the R2 value of the multicenter region density function was higher than that of the single-center region density function.The polycentric regional density function showed that the population density gradient of some centers had a downward trend,which reflected the spatial development trend of outward diffusion in these centers.Meanwhile,the variation in the estimated population density and the population density gradient exhibited differences in the central population distribution patterns at different levels.

Functional regionalization with the restriction of ecological shelter zones： A case of Zhaotong in Yunnan

Ecological shelter zones reconstruction is an ecosystem restoration and conservation project aimed to the ecological safety of nations, regions and basins. Reconstruction of ecological shelter zones of the upper reaches of the Yangtze River became one of the most important tasks of Western Development strategy. This article, taking Zhaotong as an example, studies the functional regionalization of ecological shelter zones. The study supplies a case for functional regionalization of small and medium regions whose main tasks are environment reservation. With the guidance of theories of functional regionalization, and based on the analysis of Zhaotong＇s natural, ecological and socioeconomic factors, the paper suggests five principles for factors selection. These principles include： （1） reversing order evaluation; （2） selecting main factors; （3） keeping the integrality of administrative regions of towns; and （4） making the products acceptable by local government. To analyze spatial status of selected factors, LUCC data in 2002, 1：50,000 relief maps and town-unit socioeconomic statistical data in 2004 are used. RS and GIS tools are also applied to melt traditional and modern geographical methods. This would be useful to functional regionalization research in mountainous areas. As a conclusion, the leading functional regions of ecological conservation or economic development are suggested, respectively. Zhaotong city is divided into two-level functional regions. The first-level includes three leading functional regions and they will lead developing direction of sub-regions. The second-level includes eight sub-regions, which are policy implemented regions, and will supply guidance to Zhaotong＇s ecological shelter zones reconstruction.

Speckle tracking echocardiography to assess regional ventricular function in patients with apical hypertrophic cardiomyopathy

AIM To explore regional systolic strain of midwall and endocardial segments using speckle tracking echocardiography in patients with apical hypertrophic cardiomyopathy(HCM).METHODS We prospectively assessed 20 patients(mean age 53 ± 16 years,range:18-81 years,10 were male),with apical HCM. We measured global longitudinal peak systolic strain(GLPSS) in the midwall and endocardium of the left ventricle. RESULTS The diastolic thickness of the 4 apical segments was 16.25 ± 2.75 mm. All patients had a normal global systolicfunction with a fractional shortening of 50% ± 8%. In spite of supernormal left ventricular(LV) systolic function,midwall GLPSS was decreased in all patients,more in the apical(-7.3% ±-8.8%) than in basal segments(-15.5% ±-6.93%),while endocardial GLPPS was significantly greater and reached normal values(apical:-22.8% ±-7.8%,basal:-17.9% ±-7.5%). CONCLUSION This study shows that two-dimensional strain was decreased mainly confined to the mesocardium,while endocardium myocardial deformation was preserved in HCM and allowed to identify subclinical LV dysfunction. This transmural heterogeneity in systolic strain had not been previously described in HCM and could be explained by the distribution of myofibrillar disarray in deep myocardial areas. The clinical application of this novel finding may help further understanding of the pathophysiology of HCM.

Left Ventricular Regional Systolic Function in Patient with Hypertrophic Cardiomyopathy by Quantitative Tissue Velocity Imaging

The left ventricular regional systolic functions in patients with hypertrophic cardiomyopathy （HCM） were assessed by using quantitative tissue velocity imaging （QTVI）. Left ventricular （LV） regional myocardial velocity along long- and short-axis in 31 HCM patients and 20 healthy subjects were analyzed by QTVI, and the regional myocardial systolic peak velocities （MVS） were measured. Mean MVS at each level including mitral annular, basal, middle and apical segments were calculated. The ratio of MVS along long-axis to that along short-axis （Ri） at basal and middle segments of the LV posterior wall and ventricular septum were calculated. The results showed that mean MVS was slower at each level including mitral annular, basal, middle and apical segments in the HCM patients than that in the healthy subjects （P〈0.01）. There were no significant differences in mean MVS between obstructive and non-obstructive groups in HCM patients. MVS of all regional myocardial segments along long-axis in the HCM patients were significantly slower than that in the healthy subjects （P〈0.05）, but there was no significant difference in MVS of all regional myocardial segments along long-axis between hypertrophied and non-hypertrophied group in the HCM patients. Ri was significantly lower in the HCM patients than that in the healthy subjects. The LV regional myocardial contractility along long-axis was impaired not only in the hypertrophied wall but also in the non-hypertrophied one in patients with HCM, suggesting that QTVI can assess accurately LV regional systolic function in patient with HCM and provides a novel means for an early diagnosis before and independent of hypertrophy.

Assessment of Regional Myocardial Function in Patients with Hypertrophic Cardiomyopathy by Tissue Strain Imaging

The value of tissue strain imaging （SI） in regional myocardial systolic and diastolic func tion assessment was studied. In 18 patients with nonobstructive hypertrophic cardiomyopathy （HCM） and 20 age-matched healthy subjects, regional myocardial longitudinal peak systolic strain in eject time （represented by εet） was measured at basal, mid and apical segments of septal, lateral and posterior walls of the left ventricle （LV） and compared between groups, εet had no significant difference between segments in control group （P〉0.05）, which displayed a decreasing trend from basal segments to apical ones. εet in the HCM group was significantly decreased （P（0. 05） as compared with that in the healthy group. In the HCM group, εet in the midseptum was significantly less than at the basal and apical septum, and was also less than at the rest LV walls in the same group （P〉0.01）. The systolic reversed εet was noticed in 35% of the hypertrophic segments in HCM group. Significantly negative correlation existed between the absolute value of εet and wall thickness in the midseptum （r= -0.83）. The post-systolic strain（PSS） segment number the and amplitudes in healthy group were significantly less than those in HCM group （P〈0.05）. Both regional myocardial systolic and diastolic functions were impaired in hypertrophic or non-hypertrophic segments in patients with the HCM, especially in hypertrophic segments. Strain imaging technique is a sensitive and accura tool in myocardial dysfunction assessment.

Ecological function regionalization of fluvial corridor landscapes and measures for ecological regeneration in the middle and lower reaches of the Tarim River, Xinjiang of China

The middle and lower reaches of the Tarim River are currently one of the main regions of ecological restoration in the arid areas of western China.Using the principles and method of landscape ecology,this study has chosen the fluvial corridor landscape in the middle and lower reaches of the Tarim River,and discusses the region’s ecologically functional regionalization system and issues related to its practical classification.On this basis the corresponding regionalizing principles and standards were developed which were used to qualitatively divide the three main landscapes as the ecologically functional areas in the drainage basin.The paper has also analyzed the characteristic of the study areas,and has put forward the measures for its ecological restoration.

Affinity-based human mobility pattern for improved region function discovering

The process of urbanization is formed by regular movements of human beings. It yields different functional zones in a city, such as residential zone and commercial zone. Consequently, there exists a close connection between the human mobility pattern and the city＇s zones. However, it is not easy to collect large-scale society-wide data that can precisely capture the underlying relations between the individual＇s movement and the regional functions. Hence, our knowledge for understanding the basic patterns of human mobility is still limited. In order to discover the functions of different regions in a city, we propose an affinity based method in this paper. The affinity is a recently introduced metric for measuring the correlation of two connecting node in a complex network. The proposed model groups different functional zones by measuring user＇s arrival/departure distribution via relative entropy. In addition to this, we also identify the intensity of each functional zone by taking kernel density estimation （KDE） method. In the end, some experiments are conducted to evaluate our method with a large-scale real-life dataset, which consists of 3 million cellphone users＇ records from a period of one month. Our findings on the interaction between the mobility pattern and the regional functions can capture the city dynamics efficiently and provide a valuable reference for urban planners.

CLASSES OF MEROMORPHIC FUNCTIONS ASSOCIATED WITH CONIC REGIONS

The object of this article is to introduce new classes of meromorphic functions associated with conic regions. Several properties like the coefficient bounds, growth and distortion theorems, radii of starlikeness and convexity, partial sums, are investigated. Some consequences of the main results for the well-known classes of meromorphic functions are also pointed out.

Functional magnetic resonance imaging of regional homogeneity changes in parkinsonian resting tremor

Regional homogeneity analysis of low-frequency blood oxygenation level-dependent signals from neighboring voxels enables the analysis of local neuronal synchrony. Both structural magnetic resonance imaging and resting-state functional magnetic resonance imaging scans were collected from nine Parkinson＇s disease patients with right resting tremor, and from eight age-matched normal controls. Regional homogeneity was compared between Parkinson＇s disease patients and controls. The results revealed that regional homogeneity was increased in several brain regions, including the right precuneus, right superior parietal gyrus, left anterior cingulate cortex, right middle frontal gyrus and right inferior frontal gyrus. Conversely, regional homogeneity was decreased in the cerebellar vermis in Parkinson＇s disease patients compared with healthy controls.

Spatial Function Regionalization Based on an Ecological-economic Analysis in Wuxi City, China

As a result of rapid urbanization in China, urban sprawl has increased rapidly, and land-use regulation and smart urban growth are equally important. Spatial function regionalization can provide the scientific groundwork for the regulation of land use and protection. This paper probes the system of evaluation indices and applies the methods of spatial analysis and classification clustering to the calculation of the ecologically significant value and economically significant value in each evaluation unit. After use of a classification matrix integrated by the two significant values, city space can be divided into four functional types, namely, feasible development area, moderate development area, moderate conservation area and prohibited exploiting area, and these are the basis for spatial development and control.

Aging effects of regional activation in a spatial task A functional magnetic resonance imaging study

BACKGROUND： An increasing number of studies have shown the effects of aging in basic cognitive processing and higher cognitive functions using functional magnetic resonance imaging （fMRI）. However, little is known about the aging effects in diverse cognitive abilities, such as spatial learning and reasoning. OBJECTIVE： To investigate the effect of aging on spatial cognitive performance and regional brain activation based on fMRI. DESIGN, TIME, AND SETTING： A block design for fMRI observation. This study was performed at the fMRI Laboratory, Brain Science Research Center, Korea Advanced Institute of Science and Technology from March 2006 to May 2009. PARTICIPANTS： Eight right-handed, male, college students in their 20s （mean age 21.5 years） and six right-handed, male, adults in their 40s （mean age 45.7 years）, who graduated from college, participated in the study. All subjects were healthy and had no prior history of psychiatric or neurological disorders. METHODS： A spatial task was presented while brain images were acquired using a 3T fMRI system （ISOL Technology, Korea）. The spatial tasks involved selecting a shape that corresponded to a given figure using four examples, as well as selecting a development figure of a diagram. MAIN OUTCOME MEASURES： The accuracy rate （number of correct answers/total number of items x 100%） of spatial tasks was calculated. Using the subtraction procedure, the activated areas in the brain during spatial tasks were color-coded by T-score. The double subtraction method was used to analyze the effect of aging between the two age groups （20s versus 40s）. RESULTS： The cerebellum, occipital lobe, parietal lobe, and frontal lobe were similarly activated in the two age groups. Increased brain activations, however, were observed in bilateral parietal and superior frontal lobes of the younger group. More activation was observed in bilateral middle frontal and right inferior frontal lobes in the older group. Compared with the older group, the younger men exhibited greater spatial performance （P = 0.012）. CONCLUSION： Reduced cognitive function correlated with decreased activation areas in the parietal lobe and altered activation in the frontal lobe.

网络游戏成瘾患者脑功能异常静息态功能磁共振成像研究

目的采用局部一致性(regional homogeneity,ReHo)和功能连接(functional connectivity,FC)相结合的方法探究网络游戏成瘾(Internet gaming disorder,IGD)患者静息状态下的脑局部固有连接的改变。材料与方法对44例IGD患者和49例年龄、性别、受教育年限相匹配的健康对照者进行静息态功能磁共振成像(resting state-functional magnetic resonance imaging,rs-fMRI)检查。计算并比较两组的ReHo值,以检测IGD患者脑内局部连接的改变;以ReHo值异常的脑区进行功能连接,以得到不同脑区间连接性的改变。采用网络成瘾测试(Internet Addiction Test,IAT)评估IGD的严重程度。Pearson相关分析用于评估具有ReHo改变的脑区域与IAT评分之间的关系。结果IGD组双侧内侧额上回、双侧背外侧额上回、左侧辅助运动区、右侧额中回ReHo增加;左侧枕下回、左侧枕中回、左侧舌回、左侧距状裂周围皮层、左侧梭状回、左侧颞上回以及左侧小脑ReHo值减低(体素水平P<0.005,团块水平P<0.05,高斯随机场校正)。IGD组右侧背外侧额上回与右侧额上回、双侧辅助运动区、右侧中央前回的功能连接性增加(体素水平P<0.005,团块水平P<0.05,高斯随机场校正)。此外,左侧距状裂周围皮层ReHo值与IAT评分呈负相关(r=-0.340,P=0.024)。结论在前额叶皮层、颞枕叶皮层局部连接发生改变,可能表明IGD的认知控制和奖励处理以及视觉、听觉网络已受到影响。此外,左侧距状裂周围皮层ReHo值与IAT评分呈负相关,可能为IGD的神经病理机制提供新的认识。

论区域协调发展的理论深化与实践创新

区域经济是国家经济的空间基础。无论是基于缩小区域经济差距的历史经验,还是基于理论分析,或是基于具体实践,区域协调发展均具有重要意义。自新中国成立以来,我国区域协调发展经历了四个历史阶段和三次理论演进,进行了战略基础、极点支撑和功能分工等探索实践,逐渐步入高水平协调发展阶段。但也面临区域要素流动受阻、区域发展极化、区域功能分工程度较低和区域产业转移缓慢等新问题。基于此,文章提出新时代实现区域协调发展的具体思路:完善资源要素流动的体制机制,优化重大基础设施布局,细化区域功能分工,完善区域协调发展政策体系,以新质生产力赋能区域协调发展。

流域保护区域协同立法的功能定位与规范进路

《长江保护法》《黄河保护法》为长江、黄河流域的区域协同立法提供了法律依据,在流域保护区域协同立法“入法”后,需要明晰其权力空间与运行规则,提升其科学化、规范化水平。流域保护区域协同立法在本质上仍属于地方立法,是功能主义进路下解决跨行政区域流域保护难题的一种选择,是流域整体性保护的立法回应。就其功能而言,具有落实国家立法确立的流域保护整体目标的实施性功能,以地方合作为中心,解决那些通过单独地方立法难以解决的跨行政区域地方性流域保护问题的协调性、自主性、创新性功能。在此基础上,应当通过明晰其立法层级,建立地方立法规划协同机制,改、废、释的协同机制,交叉备案与后评估机制,深化公众参与机制,完善流域保护区域协同立法的运行规则。

区域土特征函数:收敛性

无论从一个地区内建立N-s_(v)关系曲线的工程应用角度还是作为区域土特征理论的必要组成部分,构建科学的N-v_(s)函数所需的数组量都是重要问题,但以往研究为空白。采用实测数据的随机分析,研究不同样本数量下N-v_(s)特征函数的稳定性和收敛性,并提出构建不同精度N-v_(s)特征函数的数组阈值。实测数据来源于4个国家9个地区,共11个工况,对此分别进行随机分析的结果表明,随样本数量增加,N-v_(s)特征函数具有稳定性与收敛性。研究表明,一个地区内取N-v_(s)数组超过50,100,200和800,则可分别得到变异系数小于0.2,0.15,0.10和0.05的N-s_(v)特征函数。

湘西森林旅游区域生态服务功能与价值估算

【目的】湘西是我国南方重要的生态功能区,在森林旅游区域实施林分抚育协同森林旅游开发,对推动地区绿色发展有益。【方法】面积迭置获取森林旅游区域生态服务价值估算依据,采用货币价值法、森林旅游功能指数(FTFI)和偏离-份额分析法(SSM),系统评价湘西森林旅游区域生态服务价值演变与空间特征。【结果】1)近20年来湘西森林旅游区域生态服务价值增加了771.90万元/hm^(2),年均增长38.59万元/hm^(2),县均增加32.16万元/hm^(2)。区域单位面积价值排序为:3A级及以上旅游景区(352.14亿元)>国有林场(121.06亿元)>国家森林(湿地)公园(115.86亿元)>自然保护区(99.18亿元)>全国乡村旅游扶贫重点村(47.83亿元)>中国少数民族特色村寨(27.71亿元)>文物保护单位(8.12亿元),森林旅游区域年均价值居前五位的是慈利县、永顺县、桑植县、永定区和沅陵县,居后五位的是洪江市、辰溪县、麻阳县、花垣县和新晃县;2)3A级及以上旅游景区价值最少县域为洪江市(1.16万元/hm^(2)),永定区、慈利县等12个县域的自然保护区区域价值为0,靖州县、龙山县等10个县域文物保护单位价值为0.01万元/hm^(2),桑植县、泸溪县等4个县域国家森林(湿地)公园单位价值为0,国有林场、全国乡村旅游扶贫重点村、中国少数民族特色村寨单位价值最少县域为芷江县(0.18万元/hm^(2))、花垣县(0.12万元/hm^(2))和麻阳县(0.08万元/hm^(2));3)森林旅游区域的固碳释氧、涵养水源功能价值县均达390.43万元/hm^(2)和382.94万元/hm^(2),保育土壤、积累营养物质和保护生物多样性价值较大,森林景观价值县均为11.01万元/hm^(2)。各时段永定区、慈利县、桑植县、永顺县的森林旅游功能指数较大,均超过了1.5的水平值,其他20个县域基本持平。【结论】湘西森林旅游区域生态服务功能多样、价值不断增加,3A级及以上旅游景区、国有林场、国家森林(湿地)公园、自然保护区是发挥生态服务价值的主要区域类型。加强县域协作,坚持森林主体功能定位,调整森林生态绩效结构,合理划定森林生态服务功能分区,能提高森林旅游区域生态服务价值供给水平。

旱地小麦区试品系中抗旱高产相关基因的KASP标记检测

利用分子标记检测小麦区试品系,明确其优异等位基因组成,有利于进一步精准改良利用。分析KASP标记检测中存在的问题,有助于促进分子育种应用。以山东省2021—2022年小麦旱地区试24份参试品系为材料,利用32个抗旱高产相关基因的KASP标记,分析KASP标记检测中存在的异常结果和材料的优异等位基因利用情况。结果表明,未知基因型产生的主要原因是KASP反应失败或非特异扩增。混合DNA样品检测结果为杂合的主要原因是单株间基因型不一致,次要原因是错误分型。32个KASP标记中,14个标记的优异等位基因检出率超过83%,表明这些基因在育种中已经得到有效利用;17个标记的优异等位基因检出率低于50%,其中,WRKY51-2B、AX-95025477-7B、SnRK2.4A3、TaMoc-2433和NCED15个标记的优异等位基因未检出,表明这些基因在育种中利用较少,可通过分子标记辅助选择开展遗传改良。24份材料中,HQ04携带20个优异等位基因,是数量最多的,可作为基因供体用于育种。利用KASP标记开展辅助选择定向精准提高优异等位基因在小麦育种中的利用率仍有可为。

经脑沟裂间隙入路对基底核区高血压脑出血患者脑血流、神经功能及微炎症的影响

目的分析经脑沟裂间隙入路对基底核区高血压脑出血患者脑血流、神经功能及微炎症的影响。方法选择基底核区高血压脑出血患者96例,按手术方式不同分为观察组(n=47,经脑沟裂间隙入路)和对照组(n=49,常规经脑回皮质手术)。比较两组患者脑血流动力学[外周阻力(Rv)、平均血流量(Qm)、平均血流速度(Vm)]、神经功能缺损评分(NHISS)、血清神经因子[神经生长因子(NGF)、神经元特异性烯醇化酶(NSE)、神经肽(NPY)]、炎症因子[超敏C反应蛋白(hs-CRP)、金属基质蛋白酶-9(MMP-9)、肿瘤坏死因子-α(TNF-α)]水平以及并发症情况。结果观察组术后出血量、意识恢复时长、住院时长低于对照组(P<0.05)。术后两组Rv均降低,Qm、Vm均升高,血清NSE、NGF、NPY、MMP-9、hs-CRP、TNF-α水平及NHISS评分均下降,且观察组较对照组更为显著(P<0.05)。观察组气管切开、脑再出血并发症发生率低于对照组(P<0.05)。结论经脑沟裂间隙入路手术能有效改善基底核区高血压脑出血患者临床疗效和脑血流,减轻微炎症状态,促进神经功能恢复。

中国城市碳排放绩效:动态分解、空间差异与影响因素

以非径向方向距离函数为框架,构造全要素碳排放绩效指数对中国2006—2019年城市碳排放治理绩效进行测度。在此基础上从经济含义、跨期动态变化、区域均衡等层面对全要素碳排放绩效指数进行多维分解,检验中国城市碳排放绩效的影响因素。结果表明:第一,样本期内全国城市平均全要素碳排放绩效指数总体呈波动上升态势,动态分解结果显示,中国各地的平均碳排放绩效水平不断改进,创新效应对其贡献逐年增大但赶超效应贡献不足;第二,空间分异方面,珠三角、长三角、粤闽浙沿海、长江中游等东部地区城市群不仅平均碳排放绩效水平普遍较高,且碳排放绩效的增长速度较快,中西部地区仅成渝城市群碳排放绩效表现较好,中原、京津冀等城市群近年来碳排放绩效的改善速度较快;第三,基尼系数测度及其分解显示,近年中国城市碳排放绩效指数的分异程度逐步加深,分异成因主要为城市群组间差异,城市群内部差异贡献度较低;第四,Lasso分析及双固定面板模型分析结果显示,经济发展水平、清洁能源使用、金融发展、绿色环保和科技支持能够有效改善城市层面的碳排放绩效,能源消耗强度和第二产业就业人员比重对碳排放绩效具有负面影响;最后,城市群因子探测结果显示,各城市群间的驱动因子存在一定差异。

中国极地海洋微生物研究进展

极地海洋环境蕴含丰富的微生物资源,其独特的生命特征、特殊的极端环境适应及生态效应机制,都有着重要的科学研究意义及应用开发前景。回顾我国近10年来在极地海洋微生物领域的研究,所取得的主要进展包括:(1)揭示了南北极海洋微生物群落特有的结构和功能、二甲基硫/二甲基巯基丙酸内盐(DMS/DMSP)循环相关基因及可培养细菌基因组的独特生物地理学特征;(2)发现了极地海洋细菌通过代谢DMSP抵御原生动物捕食的新生态功能、温度响应新机制及新的几丁质氧化降解利用通路;(3)揭示了噬菌体对极地海洋细菌种群的调控作用;(4)阐明了极地海洋细菌产生的系列新型有机质降解酶的催化机制及其应用潜力;(5)建立了极地海洋细菌胞外多糖的制备工艺,评估了其在医学及食品等领域的应用潜力;(6)分离鉴定了系列极地海洋微生物新物种。以上研究成果先后发表在Nature Microbiology,Nature Communica-tions,Microbiome,ISME Journal等国际知名期刊上,提升了我国极地海洋微生物研究的水平、影响力和话语权。未来加强多学科交叉研究及前沿技术应用研发将进一步促进我国极地海洋微生物学研究的发展。