zonal distribution
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2021 ◽  
Author(s):  
Zhidan Ba

Take the parabolic dune of Hobq desert in Inner Mongolia as research object. Based on the GIS platform by using differential GPS data and spatial interpolation to generate DEM, then using Multi-periods high resolution images to acquire the environmental background, at the same time combine with regional wind regime and vegetation condition to measure and analyze the morphology of the parabolic dune. The result shows that the parabolic dune showed U shape in plane, and dune arms point to the west which was also wind direction. The windward slope of longitudinal profile is gentler, while leeward slope is steeper. And cross section wasn’t symmetric. The dune’s average moving speed is 11.76 m/yr. Desert ridge line’s medial axis direction is WNW-ESE, in accord with the direction of prevailing wind and resultant drift potential. Artemisia Ordosicas mainly distribute on leeward slope, two arms, and the plane ground between them, and the annual average vegetation coverage decreased 0.95%. In the long-term effect of resultant wind, the dune keeps moving forward and Artemisia Ordosica between two arms show gradual natural stage recovery which presented zonal distribution. 3S technology has already become important research method in modern Aeolian sand morphology.


Author(s):  
Sakshi Khurana ◽  
Stefano Schivo ◽  
Jacqueline R. M. Plass ◽  
Nikolas Mersinis ◽  
Jetse Scholma ◽  
...  

A fundamental question in cartilage biology is: what determines the switch between permanent cartilage found in the articular joints and transient hypertrophic cartilage that functions as a template for bone? This switch is observed both in a subset of OA patients that develop osteophytes, as well as in cell-based tissue engineering strategies for joint repair. A thorough understanding of the mechanisms regulating cell fate provides opportunities for treatment of cartilage disease and tissue engineering strategies. The objective of this study was to understand the mechanisms that regulate the switch between permanent and transient cartilage using a computational model of chondrocytes, ECHO. To investigate large signaling networks that regulate cell fate decisions, we developed the software tool ANIMO, Analysis of Networks with interactive Modeling. In ANIMO, we generated an activity network integrating 7 signal transduction pathways resulting in a network containing over 50 proteins with 200 interactions. We called this model ECHO, for executable chondrocyte. Previously, we showed that ECHO could be used to characterize mechanisms of cell fate decisions. ECHO was first developed based on a Boolean model of growth plate. Here, we show how the growth plate Boolean model was translated to ANIMO and how we adapted the topology and parameters to generate an articular cartilage model. In ANIMO, many combinations of overactivation/knockout were tested that result in a switch between permanent cartilage (SOX9+) and transient, hypertrophic cartilage (RUNX2+). We used model checking to prioritize combination treatments for wet-lab validation. Three combinatorial treatments were chosen and tested on metatarsals from 1-day old rat pups that were treated for 6 days. We found that a combination of IGF1 with inhibition of ERK1/2 had a positive effect on cartilage formation and growth, whereas activation of DLX5 combined with inhibition of PKA had a negative effect on cartilage formation and growth and resulted in increased cartilage hypertrophy. We show that our model describes cartilage formation, and that model checking can aid in choosing and prioritizing combinatorial treatments that interfere with normal cartilage development. Here we show that combinatorial treatments induce changes in the zonal distribution of cartilage, indication possible switches in cell fate. This indicates that simulations in ECHO aid in describing pathologies in which switches between cell fates are observed, such as OA.


2021 ◽  
Vol 9 ◽  
Author(s):  
Yajie Dong ◽  
Naiqin Wu ◽  
Fengjiang Li ◽  
Houyuan Lu

The magnitude and rate of the expansion of the East Asian summer monsoon (EASM) rain belt under future climatic warming are unclear. Appropriate ecological proxy data may provide an improved understanding of the spatial extension of the EASM during past warming intervals. We reconstructed the spatiotemporal pattern of the extension of the EASM since the Last Glacial Maximum (LGM), using six well-dated mollusk fossil sequences from Chinese loess sections located on the modern northern edge of the EASM. The abundance of typical dominant mollusk species indicative of EASM intensity shows a delayed response, from ∼17 ka in the southeastern sections to ∼9 ka in the northwestern sections, during the last deglacial warming. Isoline plots based on a mollusk data synthesis show that the mollusk EASM indicators have a northeast–southwest zonal distribution for both the present-day, the cold LGM, and the warm mid-Holocene, which is consistent with the spatial pattern of modern precipitation. The resulting estimated expansion rate of EASM intensity accelerated during ∼12–9 ka (∼50 km/ka), which corresponds to the early Holocene interval of rapid climatic warming, a northwestward shift of ∼150 km compared to today. This implies that the northern fringe of the EASM in northern China will become wetter in the coming century, under moderate warming scenarios.


2021 ◽  
Vol 6 (4) ◽  
pp. 213-219
Author(s):  
I. N. Kinash ◽  
M. E. Puseva ◽  
Ch. Z. Butaev ◽  
T. K. Verkhozina ◽  
E. G. Ippolitova

Radial fracture is the most common trauma to the musculoskeletal system and accounts for 50 % of traumatic injuries to the bones of the upper limb. Disability in patients with fractures of the forearm bones ranges from 6 to 8 months, so the choice of the most effective method of treatment is very relevant. Currently, an important point is the tendency of optimizing the transosseous method by eliminating the disadvantages and looking for new advantages of external fixation. Bone fracture and associated surgical intervention are always accompanied by varying degrees of changes in the links of the central nervous system, hemodynamics and metabolism. In order to study the bioelectrical activity of the brain in 47 patients with a fracture of the radial diaphysis treated in the Traumatology Department of the Irkutsk Scientific Centre of Surgery and Traumatology, in the pre- and postoperative period we compared EEG indicators of two variants of the layout of the external fixation apparatus (EF): wire and rod. Analysis of the rhythms of bioelectrical activity of the brain in both groups in the preoperative period revealed a normal zonal distribution with the dominance of the alpha rhythm on the EEG, which generally reflects a rather high degree of organization of neuroactivity and indicates the stability of cerebral homeostasis. At the same time, in the group of patients with a wire-mounted EF device in the postoperative period, EEG indices significantly differed from the values of the norm and ndicators in the group with a rod-shaped arrangement. A decrease in the amplitude of alpha and beta rhythms was noted, as well as a shift in the frequency of bioelectric activity towards slow waves, which is a sign characteristic of discirculatory encephalopathy. An EEG study using the method of transosseous osteosynthesis with EF devise of a rod assembly showed its greater efficiency compared to the use of an EF device of a wire assembly during treatment and rehabilitation. Thus, the study of the bioelectric activity of the brain is a reliable method for assessing its functional state after an injury, as well as the effectiveness of the treatment.


2021 ◽  
Vol 10 (10) ◽  
pp. 695
Author(s):  
Lijun Chen ◽  
Haiping Zhang ◽  
Haoran Wang ◽  
Peng Wu

The effect of the plum rain weather event on cycling trips reflects the climate resilience of the public bicycle system. However, quantitative studies regarding the impact of plum rain on public bicycle users and corresponding spatial heterogeneity have not been paid much attention. This paper explores the spatial pattern of affected levels from the perspective of cyclist number, place semantics and riding distance. Corresponding public bicycle trips in normal weather are predicted by spatial-temporal random forest prediction. GIS neighborhood statistics and clustering algorithms are adapted to analyze and visualize the affected levels using origin-destination data of public bicycle trips and point of interest data of city public facilities. It is proved that there is an obvious spatial difference in affected levels by plum rain from three dimensions. In the dimension of the number of cyclists, the docking stations with different affected levels are distributed across the whole urban area. In the place semantic dimension, the docking stations with high affected levels show a clustered zonal distribution in the city center. In the dimension of cycling distance, the docking stations with high affected levels are mainly distributed in the periphery of the central urban area. The study theoretically expands the impact mechanism of environment and active transport. It is beneficial for the early monitoring, warning and assessment of climate change risks for public bicycle planning and management.


Land ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1081
Author(s):  
He Sun ◽  
Xueming Li ◽  
Yingying Guan ◽  
Shenzhen Tian ◽  
He Liu

For megacities, they are in a period of transformation from extensive development to smart growth. Recognizing new characteristics and new changes of the residential space in megacities under the backdrop of new development has great practical significance for realizing the sustainable development of the city. As the only megacity in Northeast China, Shenyang was selected to be the research object, with 1989–2018 as the research period. The research comprehensively used multiple spatial representation methods and statistical methods to study the residential space pattern and driving factors in Shenyang City. The results showed that: (1) Residential space expansion can be divided into four stages: slow development, rapid expansion, speedy expansion, and stable extension. (2) The residential space structure presented a spatial evolution characteristic of overall expansion, forming multiple secondary core density centers. The east-west direction had a larger extension range than the northeast-southwest direction. There was an axisymmetric zonal distribution on both sides of the Hun River. (3) The agglomeration of different residential forms was obvious, and the spatial heterogeneity was increasingly stronger. (4) Urban planning measures and economic strength were the main driving forces of residential space expansion.


Author(s):  
V.B. Limanskaya ◽  
U.A. Nuraliyeva ◽  
O.B. Krupskiy ◽  
A.A. Baisabyrova ◽  
A.D. Jymagaliev ◽  
...  

Analysis of the features of Western Kazakhstan for the presence and level of thermal regime, phytocenotic diversity as a source of food for bees and other important indicators are necessary to establish the level of intensity and search for ways to increase the efficiency of the beekeeping industry, which will become a significant replenishment of the fodder base for farm animals. In addition, the use of such honey plants as sweet clover, alfalfa, clover, sainfoin significantly improves soil fertility in crop rotation structures, since the use of leguminous herbs significantly increases soil nitrogen. In cases where sweet clover is sown on lands with a high salt content, their salinity is significantly reduced, which today makes it possible to stop soil degradation, and this is a solution to global problems. The climate of the western regions of Kazakhstan is characterized by a sharp continentality, which increases from northwest to southeast. The signs of continentality are distinguished by sharp temperature contrasts of day and night, winter and summer, and a rapid transition from winter to summer. Instability and scarcity of atmospheric precipitation, intensity of evaporation processes and an abundance of direct sunlight throughout the growing season are typical throughout the region. Intensive crop production is mainly concentrated in the steppe and dry-steppe zones located in the northern part of the West Kazakhstan and Aktobe regions. The territory of intensive agriculture in the west of Kazakhstan for many years has formed a range of agricultural crops, priority for crop production, the main of which are winter cereals, spring breads, legumes. The entire grain wedge accounts for 50% of all sown area. On average, 12% of the area is sown annually with oilseeds and 36% is allocated for sowing forage crops, including typical nectar-bearing crops: sunflower, safflower, alfalfa, sainfoin, sweet clover. Mustard, buckwheat, camelina are sown in small amounts. The natural and climatic conditions of Western Kazakhstan in terms of indicators and characteristics that affect the activity of bee pollination are complex, unstable, but quite acceptable for targeted involvement in agricultural production. Seed production of field crops with the involvement of cultivated species of pollinating insects in the process of pollination can increase the yield of seed production by 45-50%.


2021 ◽  
Vol 12 (3) ◽  
pp. 608-627
Author(s):  
I. Yousef ◽  
V. P. Morozov ◽  
Mohammad El Kadi ◽  
Abdullah Alaa

We have investigated the tectonic and erosion features of the Upper Triassic (Mulussa F Formation) and Lower Cretaceous (Rutbah Formation) sediments in the Euphrates graben area and analysed their influence on changes in the thickness and zonal distribution patterns of these sediments. In this study, the geological modeling software of Petrel Schlumberger is used to model the regional geological structure and stratigraphy from the available geological and geophysical data.The Upper Triassic and Lower Cretaceous sediments (in total, almost 800 m thick) are the major hydrocarbon reservoirs in the Euphrates graben, which contain approximately 80 to 90 % of the total hydrocarbon reserve in this area. These sedimentary zones experienced variable changes in thickness and zonal distribution due to erosion processes caused by the two major regional unconformities, the Base Upper Cretaceous (BKU) and Base Lower Cretaceous (BKL) unconformities. The maximum thickness of the Upper Triassic sediments amounts to 480 m in the central parts of the Euphrates graben and along the NW-SE trend, i.e. in the dip direction of the Upper Triassic Mulussa F Formation. Towards the NE flank of the graben near the Khleissia uplift and the SW flank near to the Rutbah uplift, the thickness of the Upper Triassic sediments is gradually decreased due to their partial or total erosion caused by the BKL unconformity, and also due to a less space for sediment accumulation near the uplifts. The thickness of the Lower Cretaceous sediments increases in the northern, NW and NE flanks of the graben. Their maximum thickness is about 320 m. The BKL unconformity is the major cause of erosion of the Lower Cretaceous sediments along the southern, SE and SW flanks of the graben. In the Jora and Palmyra areas towards the NW flank of the Euphrates graben, the Upper Triassic and Lower Cretaceous sediments show no changes in thickness. In these areas, there was more space for sediment accumulation, and the sediments were less influenced by the BKL and BKU unconformities and thus less eroded.


Land ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 833
Author(s):  
Baochao Li ◽  
Xiaoshu Cao ◽  
Jianbin Xu ◽  
Wulin Wang ◽  
Shishu Ouyang ◽  
...  

In this paper, we study the characteristics of the spatial–temporal pattern of land used for transportation at the county level since the implementation of the reform and opening-up policy in China and discuss the factors that influence the spatial differences between lands used for transportation in order to provide a reference for the formulation of traffic policies. The authors used ArcGIS spatial analysis, an ordinary least squares (OLS) regression model, and a geographic detector model based on the data of the transportation network at the county level in China from 1978 to 2018. We obtained the following results: (1) The land used for transportation at the county level in China is divided by the Hu Huanyong Line, which is characterized by spatial variation, where the southeastern region is higher than the northwestern region. (2) Counties with a high proportion of land used for transportation show obvious changes, characterized by the transformation from the “corridor” zonal distribution of arteries to the “diamond” group distribution of major city clusters, reducing the gap in land used for transportation at the county level in China. (3) The level of industrialization, per capita gross regional product (PGRP), and ratio of the non-agricultural working population all have an incentivizing impact on the increase in land used for transportation at the county level in China. We conclude that the land used for transportation at the county level in China is jointly decided by the economy, industry, and population. Therefore, we believe that it is necessary to promote fast economic growth, the upgrading of industrial structures, and population density to achieve the balanced development of land used for transportation at the county level in China.


2021 ◽  
Vol 63 (7) ◽  
pp. 606-611
Author(s):  
Jiachen Liu ◽  
Jinliang Wang ◽  
Huiping Qi ◽  
Huiqin Chen

Abstract During hot ring rolling and subsequent air-cooling processes, the as-cast metal alloy undergoes a complicated microstructural evolution. In this paper, the grain refinement of as-cast 42CrMo ring billet during hot ring rolling and air-cooling was conducted by FEM simulation and tests. Moreover, the grain refinement mechanism of as-cast 42CrMo was also studied by comparison of single-pass deformation and multi-pass deformation with short pass interval time, with the purpose of studying the influence of the deformation process on grain refinement supported by the results of FEM simulation. As a result, effective strain and average grain size of the ring show zonal distribution characteristics The effective strain on the inner and outer layers of the ring is large, contributing to fine and homogeneous grains. In contrast, the cumulated effective strain on the interlayer of the ring is small, resulting in inhomogeneous and mixed grains and large average grain size. Grain growth occurs during subsequent air-cooling. The microstructural distribution of the hot rolled ring was confirmed by a hot ring rolling test.


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