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© 2018 Elsevier B.V. Background and Objective: It can be challenging to delineate the target object in anatomical imaging when the object boundaries are difficult to discern due to the low contrast or overlapping intensity distributions from adjacent tissues. Methods: We propose a topo-graph model to address this issue. The first step is to extract a topographic representation that reflects multiple levels of topographic information in an input image. We then define two types of node connections - nesting branches (NBs) and geodesic edges (GEs). NBs connect nodes corresponding to initial topographic regions and GEs link the nodes at a detailed level. The weights for NBs are defined to measure the similarity of regional appearance, and weights for GEs are defined with geodesic and local constraints. NBs contribute to the separation of topographic regions and the GEs assist the delineation of uncertain boundaries. Final segmentation is achieved by calculating the relevance of the unlabeled nodes to the labels by the optimization of a graph-based energy function. We test our model on 47 low contrast CT studies of patients with non-small cell lung cancer (NSCLC), 10 contrast-enhanced CT liver cases and 50 breast and abdominal ultrasound images. The validation criteria are the Dice's similarity coefficient and the Hausdorff distance. Results: Student's t-test show that our model outperformed the graph models with pixel-only, pixel and regional, neighboring and radial connections (p-values

Hazardous and toxic waste are not only produced by industry, but also by household. But in fact, the household activities also produce Household Toxic and Hazardous Waste (HTHW). Considering the potential of the impact of HTHW to the reduction of environment quality, the effort of HTHW management must have been started well. One important aspect in the management strategy is to determine the characteristics and the HTHW generation. The method used to determine the characteristics HTHW refers to SNI 19-2454-2002, while the calculation HTHW generation refers to the SNI 19-3694-1994 calculated based on weight and volume. Sampling was conducted in four districts of Semarang (Pedurungan, Semarang Barat, Semarang Utara and Banyumanik). The samples used in this study were 400 families were calculated based on the proportion of Slovin Formula. Data analysis performed using Analysis of Variance (ANOVA) and Kruskal-Walis test (α = 0.05). The largest characteristic of HTHW in Semarang City is infectious (79%), further Poisonous (13%), Combustible (6%) and Corrosive (2%). While HTHW generation is 0.01 kg/person/day (5.1% MSW). Statistical test result showed there was significant difference (p-value : 0.001) between HTHW generation based on economic level, but there was no significant difference (p-value :0.442) between HTHW characteristics in Semarang city. Level of education, occupation, income level and lifestyle may become potential factor in difference characteristics and HTHW generation in Semarang city.

The availability of lake bathymetry maps is imperative for estimating lake water volumes and their variability, which is a sensitive indicator of climate. It is difficult, if not impossible, to obtain bathymetric measurements from all of the thousands of lakes across the globe due to costly labor and/or harsh topographic regions. In this study, we develop a new digital lake bathymetry model (DLBM) using the step-wise water recession method (WRM) to generate 3-dimensional lake bathymetric maps based on the digital elevation model (DEM) alone, with two assumptions: (1) typically, the lake&rsquo, s bathymetry is formed and shaped by geological processes similar to those that shaped the surrounding landmasses, and (2) the agent rate of water (the thickness of the sedimentary deposit proportional to the lake water depth) is uniform. Lake Ontario and Lake Namco are used as examples to demonstrate the development, calibration, and refinement of the model. Compared to some other methods, the estimated 3D bathymetric maps using the proposed DLBM could overcome the discontinuity problem to adopt the complex topography of lake boundaries. This study provides a mathematically robust yet cost-effective approach for estimating lake volumes and their changes in regions lacking field measurements of bathymetry, for example, the remote Tibetan Plateau, which contains thousands of lakes.

Evaluation of synchronization between myoelectric signals can give new insights into the functioning of the complex system of porcine myometrium. We propose a model of uterine contractions according to the hypothesis of action potentials similarity which is possible to detect during propagation in the uterine wall. We introduce similarity measures based on the concept of synchronization as used in matching linear signals such as electromyographic (EMG) time series data. The aim was to present linear measures to assess synchronization between contractions in different topographic regions of the uterus. We use the cross-correlation function (ƒx,y[l], ƒy,z[l]) and the cross-coherence function (Cxy[ƒ], Cyz[ƒ]) to assess synchronization between three data series of a diestral uterine EMG bundles in porcine reproductive tract. Spontaneous uterine activity was recorded using telemetry method directly by three-channel transmitter and three silver bipolar needle electrodes sutured on different topographic regions of the reproductive tract in the sow. The results show the usefulness of the cross-coherence function in that synchronization between uterine horn and corpus uteri for multiple action potentials (bundles) could be observed. The EMG bundles synchronization may be used to investigate the direction and velocity of EMG signals propagation in porcine reproductive tract.

Rainfall erosivity is the main driver for soil detachment and sediment transport, and represents the climatic factor most influencing the risk of soil erosion at a given site. Our objectives were to explore 15 min rainfall breakpoint data from 51 rain gauges in the northeastern part of Austria to (1) calculate rainfall erosivity values for this region, and (2) analyze statistically whether there exists a temporal evolution in rainfall erosivity. Rainfall data (May to October) covered between nine and 53 years. Rain gauges were located at elevations between 150 and 970 m a.s.l., and mean rainfall depths were 514 (±169) mm and 652 (±156) mm for Lower Austria (LA) and Upper Austria (UA), respectively. The calculated rainfall erosivity factor (R factor) ranged from 273 to 1599 with an average of 884 MJ mm ha -1 h -1 in LA and from 637 and 1697 with an average of 982 MJ mm ha -1 h -1 in UA. Rainfall depths and erosivities showed greater variability in LA than in UA, which can be attributed to the different ranges of topographic regions in LA. For both states, relationships could be established between average rainfall from May to October and the R factor, with correlation coefficients between 0.77 (LA) and 0.85 (UA). Overall, for the same rainfall amounts, rainfall erosivity was lower in UA than in LA. In LA, time series analyses showed a significant temporal increasing trend in rainfall intensity, rainfall erosivity, and storm number and intensity. These positive trends at 90% of the stations with data sets of >25 years indicate possible future R factor increases and increasing erosion risk. In UA, only 25% of the rain gauges showed a significant positive trend in rainfall erosivity, and 40% showed a significant increase in rainfall intensity. Changes in rainfall patterns were more distinct in eastern Austria than in northern Austria, thus impacting runoff, infiltration, and erosion processes in this area in the future.

Thymic nurse cells are defined in vitro as multicellular complexes of epithelial cells and thymocytes. Although these structures have been implicated in the intrathymic differentiation of thymocytes, little is known about the biology of this cell complex and about the occurrence of the cells in the thymus in situ. Therefore, to clarify the matter, in this review we have presented characteristics of epithelial cells capable of forming complexes with thymocytes, in light of the literature data and the experience of the authors. The structure of cells within the complexes allowed us to distinguish three types of thymic nurse cells. Three-dimensional reconstruction of the thymus and observations employing TEM and SEM demonstrated the presence of distinct types of complexes in various topographic regions of the thymus. Where possible, the functional relevance of the morphological data was analyzed.

The course of GFAP expression by astrocytes has been immunohistochemically investigated during the first 30 weeks after human brain injury. In order to provide reliable data for a forensic wound age estimation, a quantitative morphometric analysis was performed considering the different topographic regions of the cortex as well as of the white matter. Compared to the GFAP immunoreactivity in unaltered control tissue, significantly increased numbers of GFAP positive astroglial cells could be detected adjacent to the cortical contusion from 1 day up to 4 weeks after brain injury.

Current emphasis on risk factors associated with established vaccines and pressing needs for vaccines against certain viral transmitted diseases have stimulated the search for new conceptual and practical approaches to vaccine production. Among these developments, the idiotope vaccine method has produced promising results. In this review the basic and conceptual principles for idiotype vaccine design are discussed. A novel approach for identifying idiotopic structures in the three dimensional structure of internal idiotope antigens is developed. The method is based on the relationship of the immune response with the evolutionary variation and diversity of the immunoglobulin family. Idiotopic structures are found in specialized topographic regions on the surface of the immunoglobulin molecule. The knowledge of these idiotope domains will facilitate the synthesis of idiotope expressing peptides and the computer modeling of the three dimensional structure of internal idiotope antigens. Finally, the existing evidence for successful application of the idiotope vaccine method is summarized and new disease groups are identified which could benefit from the development of idiotope vaccines.