P-集合的记忆特征研究

P-集合(packet sets)是一个集合对,它由内P-集合(internal packet sets)与外P-集合(outer packet sets)共同构成;利用P-集合的概念与结构,给出内P-集合的f-记忆集合概念,内P-集合的f-记忆度量方法;f-变异度量方法;提出内P-集合的f-记忆f-变异关系定理;外P-集合的軃f-记忆集合概念,外P-集合的軃f-记忆度量方法;軃f-变异度量方法;提出并证明了外P-集合的軃f-记忆軃f-变异关系定理。

Events of decadal thermocline variations in the South Pacific Ocean

The SODA data generated from a numerical model with data assimilation axe used to study the decadal thermal anomalies in the thermocline of the South Pacific. Three notable events of decadal thermocline variations are found. First, two major warm subduction events originated from outcrop regions centered at 30°S, 150°W in the South Pacific Ocean occurred between 1960s and 1980s propagating toward the western Tropics and at 30°S, 90°W in the late 1970s propagating directly toward the eastern Tropics. Second, a special westward warm event originating from the eastern boundary around 15°S occurred in the early 1980s. Thirdly, a distinct zonal location transition of the positive temperature anomalies near 10°S took place in the late 1970s. The results suggest that the warm events in the subtropical South Pacific region are important to the decadal variability of the western tropical Pacific before the late 1970s and to the eastern tropical Pacific after the late 1970s.

Interclonal and within-tree variation in wood properties of poplar clones

The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3 m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-95 and Nanlin-895, respectively, for providing information on variation patterns of wood density, fiber characteristics and holocellulose content within trees and among clones. The results showed that significant variations about wood density, cellulose content, fiber diameter and the ratio of fiber length to diameter existed among poplar clones examined. Variance analysis indicated that there were significant differences in wood basic density, fiber length, fiber diameter and cellulose content among the growth rings, which had an increasing tendency along the direction from pith to bark. The significant differences also existed in wood basic density, fiber length and fiber diameter at different tree height. The mean wood basic density had a general increase trend with increasing height of trees and the lowest was found at the base, while fiber length and fiber diameter had a general decline pattern with increasing height of trees and the biggest value was observed at the height of 5.6 m. Regression analysis indicated that the relationship between examined wood properties and growth ring number (cambial age), and the relationship between examined wood properties and tree height can be described by polynomial functions.

Effect of Water Salinity on the Spatial Variability of Soil and Plant Parameters

Spatial pattern and interdependence of different soil and plant parameters were examined in green bean field experiment carried out at the Mediterranean Agronomic Institute of Bari （MAIB）, Italy. The study aimed to identify the spatial distribution of soil and plant parameters and their relationship at transects scale. The experiment consisted of three transects of 30 m length and 4.2 m width, irrigated with three different salinity levels （1 dSm＂1, 3 dSm1, 6 dSml）. Soil measurements （electrical conductivity and soil water content） were monitored along each transect in 24 sites, using TDR probe installed vertically at soil surface. Water storage was measured by using Diviner sensor for calculating directly the evapotranspiration fluxes along the whole soil profile under the different salinity levels imposed during the experiment. In the same 24 sites, crop monitoring involved measurements of Leaf Area Index （LAI）, Osmotic Potential （OP）, Root length Density （RID） and Evapotranspiration fluxes （ET）. Soil and plant properties were analyzed using both classical and geostatistical methods which included descriptive statistics, semivariograms and cross-semivariograms. Results indicated that moderate to large spatial variability existed across the field for soil and plant parameters, especially under the 6 dSm1 salinity treatment. A relatively satisfactory fit of the experimental cross-semivariogram was obtained for the 6 dS1, thus indicating similar spatial structures of the pairs of compared variables. By contrast, the experimental cross-semivariograms observed under the 3 dS~ treatment indicated no significant correlation structure between the compared variables. Overall, the results observed in the 3 dSm-1 were not significantly different from those obtained in the 1 dSm-1 transect and suggested a general insensitivity of the crop response to those levels of salinity.

What the Hell Am I Doing Here？ A Look at a Series of Geriatric Centers, Profile of the Institutionalized Persons and Reasons for Admission

The main objective of this study was always to know the profile of the institutionalized people in our environment, to know their reality： age, age of admission, level of dependency and evolution during their stay, years of stay, number of children, reason for admission. We use data from more than 600 patients from different residences of different backgrounds： public and private, lay and religious, rural and urban. We performed a descriptive study expressing the results in percentages with standard deviation and later evaluated the statistical significance of the differences using the student＇s t-test for the quantitative and Chi-square variables to compare qualitative variables. The results of the study are numerous and of diverse nature, because of their extension, from the general profile of the resident, to the important gender differences, attributed in principle to the different roles of each gender in the studied generations. There are also differences depending on the funding, the reason for admission or the environment. This is at the end only the beginning of a large comparative study with non-institutionalized population, in order to compare this population.

Geographical Variation in Oligochaete Density and Biomass in Subtropical Mangrove Wetlands of China

Oligochaetes play an important role in nutrient cycling and energy flow in benthic food webs as well as in mangrove wetlands. However, they have not been as extensively studied as other macrofaunal groups such as polychaetes, gastropods, bivalves, and crustaceans. Under the assumption that oligochaete density and biomass obey specific geographical distribution patterns in subtropical mangrove wetlands of China, we investigated these two parameters in the Luoyang Estuary of Quanzhou Bay, Zhangjiang Estuary and Gaoqiao mangrove wetlands. A geographical gradient in oligochaete density was present in Aegiceras corniculatum and Kandelia obovata habitats, whereby it decreased from lower latitudes to higher latitudes. Further, ANOVA tests on oligochaete distribution revealed that both oligochaete density and biomass were significantly influenced by region, season and region × season at the A. corniculatum and K. obovata habitats. The annual average oligochaete density and biomass at the A. corniculatum habitat were higher than that at the K. obovata habitat, in both the Luoyang and Zhangjiang estuaries. There were significant correlations between oligochaete density and biomass and sediment particle size parameters, confirming that sand, silt, and clay contents were the key environmental factors affecting oligochaete distribution.

基于字段感知的文本协议灰盒模糊测试方法

基于变异的灰盒协议模糊测试方法使用便捷、可扩展性好,但缺乏协议报文格式信息,只能对报文整体进行变异以产生测试用例,导致生成的大部分测试报文会被被测协议实现直接拒绝,严重影响测试效率。针对这一问题,提出了基于字段感知的文本协议模糊测试方法。该方法在基于变异的协议模糊测试中加入了模板学习的概念,使用分隔符划分报文字段,使用字段字典获取每个字段的合法取值;然后,针对划分后的报文,设计了多种字段级的变异策略,并根据每个字段可能的取值数量和覆盖率反馈计算相应的字段变异能量;此外,还利用对报文进行字段划分的结果,对被测协议实现的状态进行更细粒度的刻画。实验结果表明,该方法可以提高经典的基于变异的协议模糊测试框架AFLNET产生的可被被测协议实现接受的测试用例的比例,进而将测试效率提高到5倍以上。这表明基于变异的协议模糊测试方法普遍存在的可被接受的测试用例比例过低的问题确实会影响最终的测试效率,改善测试用例的被接受率可以大幅提高测试效率。

Mandatory criteria for the application of variability-based parameters of fluid responsiveness: a prospective study in different groups of ICU patients

Background and objective： Stroke volume variation（SVV） has high sensitivity and specificity in predicting fluid responsiveness. However, sinus rhythm（SR） and controlled mechanical ventilation（CV） are mandatory for their application. Several studies suggest a limited applicability of SVV in intensive care unit（ICU） patients. We hypothesized that the applicability of SVV might be different over time and within certain subgroups of ICU patients. Therefore, we analysed the prevalence of SR and CV in ICU patients during the first 24 h of Pi CCO-monitoring（primary endpoint） and during the total ICU stay. We also investigated the applicability of SVV in the subgroups of patients with sepsis, cirrhosis, and acute pancreatitis. Methods： The prevalence of SR and CV was documented immediately before 1241 thermodilution measurements in 88 patients. Results： In all measurements, SVV was applicable in about 24%. However, the applicability of SVV was time-dependent： the prevalence of both SR and CV was higher during the first 24 h compared to measurements thereafter（36.1% vs. 21.9%; P0.001）. Within different subgroups, the applicability during the first 24 h of monitoring ranged between 0% in acute pancreatitis, 25.5% in liver failure, and 48.9% in patients without pancreatitis, liver failure, pneumonia or sepsis. Conclusions： The applicability of SVV in a predominantly medical ICU is only about 25%–35%. The prevalence of both mandatory criteria decreases over time during the ICU stay. Furthermore, the applicability is particularly low in patients with acute pancreatitis and liver failure.