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Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 81
Author(s):  
Zahra Ghassabi ◽  
Ebrahim Fattahi ◽  
Maral Habibi

Analyzing atmospheric circulation patterns characterize prevailing weather in a region. The method of principal component analysis and clustering was used to classify daily atmospheric circulation patterns. The average daily geopotential height of 500 hPa with 0.5° resolution of the ECMWF (1990–2019) were extracted from the Middle East. The S array was used to identify air types, and k-means clustering was used to classify daily air types. All days were divided into eighteen groups. Then, the surface maps and moisture flux divergence at the 850-hPa level of each pattern were studied. The, the connection between circulation patterns and precipitation occurrence is investigated by the PI index. The existence of a variety of precipitation and temperature regimes and consequent dry/wet periods is related to the type and frequency of the circulation patterns. In patterns with south to southwesterly currents, the low-pressure surface center extends from the south of the Red Sea to southern Turkey and is associated with the mid-level trough, where the moisture fluxes converge in the south of the Red Sea, southwest/south of Iran, and east of the Mediterranean Sea. Therefore, according to the intensity of the patterns, the most precipitation falls in the country’s western half, and the Zagros Mountain’s wind side. With the eastward movement of the Cyclonic patterns, the rainfall area extends to the eastern half of the country. With the pattern that the thermal low surface pressure extends to 35 °N latitude and is associated with the mid-level subtropical high, almost no rain occurs in the country.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Xia Qiu ◽  
Xiaoying Zhong ◽  
Honglai Zhang

To enhance the depth of excavation and promote the intelligence of acupoint compatibility, a method of constructing weighted network, which combines the attributes of acupoints and supervised learning, is proposed for link prediction. Medical cases of cervical spondylosis with acupuncture treatment are standardized, and a weighted network is constructed according to acupoint attributes. Multiple similarity features are extracted from the network and input into a supervised learning model for prediction. And, the performance of the algorithm is evaluated through evaluation indicators. The experiment finally screened 67 eligible medical cases, and the network model involved 141 acupoint nodes with 1048 edge. Except for the Preferential Attachment similarity index and the Decision Tree model, all other similarity indexes performed well in the model, among which the combination of PI index and Multilayer Perception model had the best prediction effect with an AUC value of 0.9351, confirming the feasibility of weighted networks combined with supervised learning for link prediction, also as a strong support for clinical point selection.


2021 ◽  
Vol 87 (9) ◽  
pp. 649-660
Author(s):  
Majid Rahimzadegan ◽  
Arash Davari ◽  
Ali Sayadi

Soil moisture content (SMC), product of Advanced Microwave Scanning Radiometer 2 (AMSR2), is not at an adequate level of accuracy on a regional scale. The aim of this study is to introduce a simple method to estimate SMC while synergistically using AMSR2 and Moderate Resolution Imaging Spectroradiometer (MODIS) measurements with a higher accuracy on a regional scale. Two MODIS products, including daily reflectance (MYD021) and nighttime land surface temperature (LST) products were used. In 2015, 1442 in situ SMC measurements from six stations in Iran were used as ground-truth data. Twenty models were evaluated using combinations of polarization index (PI), index of soil wetness (ISW), normalized difference vegetation index (NDVI), and LST. The model revealed the best results using a quadratic combination of PI and ISW, a linear form of LST, and a constant value. The overall correlation coefficient, root-mean-square error, and mean absolute error were 0.59, 4.62%, and 3.01%, respectively.


2021 ◽  
pp. 54-58
Author(s):  
Yu.Yu. Yarov

The issues of clarifying the key mechanisms of development and course of generalized periodontitis in different conditions of reactivity of the organism remain relevant. The aim of the research is study of the peculiarities of course of the inflammatory-destructive process in the periodontium according to the dynamics of clinical and paraclinical indicators depending on the state of reactivity of the body in the conditions of modeling hyper- and hyporeaction. Materials and methods. The experiments were performed on 24 adult not purebred dogs weighing 8-12 kg. The animals were divided into three equal groups. In the first group, drugs that disrupt the reactivity of the organism were not used (normoreactivity of the organism). In the second group drugs simulated the state of hyperreactivity, and in the third they provoked the condition of the hyporeactivity of the organism. The condition of periodontal tissues was assessed initially, on the 14th and 28th day of observation of clinical and paraclinical parameters (creviculars liquor, PMA indices, PI Russell, GI Fedorov-Volodkina, Kulazhenko's test). Results. On the 14th day of modelling the states of hyper- and hyporeactivity of the organism a number of differences in the nature of inflammation in periodontal tissues were revealed in animals of different groups. Control of the amount of creviculars liquor increased in 1,1 times, PMA indices, PI Russell, GI Fedorov-Volodkina, Kulazhenko's test, respectively, in 1,12; 1,19; 1,33 and 1,29 times (p <0,05). On the 28th day of the experiment, significant differences in the intensity of the destructive process in animals with unchanged and changed reactivity of the organism attracted attention. Thus, in cases of normoreactivity the depth of periodontal pockets reached 3 mm, the mobility of the teeth was I degree, with the changed - the depth of periodontal pockets was 5-6 mm, the mobility of the teeth was II-III degree. The amount of creviculars liquor, reflecting the intensity of the inflammatory reaction, increased compared with the 14th day, 1,3 times (p <0,05); PMA index, which characterizes the prevalence of gingivitis, and the Kulazhenko test probably did not change (p> 0,05); Russell's PI index, which indicates a pronounced intensity of inflammatory-destructive periodontal lesions, increased 2,05 times (р <0,05). Conclusions. Thus, in cases of normoreactivity of organism the inflammatory-destructive process in periodontium has moderate nature; when modelling the hyper- and hyporeactivity of the organism it acquires the character of “rapidly progressing periodontitis”. Therefore, it is necessary to continue studying the question of explaining the mechanism of different clinical course of the inflammatory-destructive process with changed and unchanged reactivity of the organism.


Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 668
Author(s):  
Timur Nizamutdinov ◽  
Eugenia Morgun ◽  
Alexandr Pechkin ◽  
Jakub Kostecki ◽  
Andrzej Greinert ◽  
...  

Dynamically developing urbanization causes a number of environmental effects, including those related to the chemical transformation of soils. Relatively less information about the urban areas of the Arctic and Subarctic zones, constructed mostly on permafrost and intensively populated areas can be found. By the example of the analysis of basic soil properties and concentrations of trace metals in the soils of the cities of Salekhard, Urengoy, Nadym, Novy Urengoy and Gaz Sale (the Yamalo-Nenets Autonomous District), as well as various functional zones within the cities, the relationship between the age of the cities, the level of anthropogenic pressure and the type of parent materials and the character of accumulation of metals in the soil profile of urban soils have been described. The direct correlation was found between the content of Pb, Cr, Ni, As and soil sorption characteristics. In young cities built on sandy sediments, there is less accumulation of heavy metals in the topsoil horizons. Relatively higher concentrations of Cu and Cd were noted in soils of industrialized cities, regardless of functional zones. The higher content of Cr, Ni, Cu, Zn, As and Pb has been registered in older zones also frequently used for residential purposes. The calculated values of the PI index for some functional zones of young cities show the medium and high content of heavy metals. The analysis of Igeo and PLI indices shows a large diversity both in relation to individual cities and their functional zones. Soil quality, in spite of the high level of anthropogenic load, was assessed as mostly satisfactory.


Author(s):  
Gopalapillai Indulal ◽  
Liju Alex ◽  
Ivan Gutman
Keyword(s):  
Pi Index ◽  

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Min Hu ◽  
Haidar Ali ◽  
Muhammad Ahsan Binyamin ◽  
Bilal Ali ◽  
Jia-Bao Liu ◽  
...  

Structure-based topological descriptors of chemical networks enable us the prediction of physico-chemical properties and the bioactivities of compounds through QSAR/QSPR methods. Topological indices are the numerical values to represent a graph which characterises the graph. One of the latest distance-based topological index is the Mostar index. In this paper, we study the Mostar index, Szeged index, PI index, ABC GG index, and NGG index, for chain oxide network COX n , chain silicate network CS n , ortho chain S n , and para chain Q n , for the first time. Moreover, analytically closed formulae for these structures are determined.


Author(s):  
Meng-yun Li ◽  
Luo liu ◽  
Fu Zhang ◽  
Xue-min Zhu ◽  
Li-fang Si ◽  
...  

Background: 6-furfuryloaminopurine (KT) is the first compound to be identified as a cytokinin. Despite that there are many studies related to KT but the mechanism of KT in resisting immunosenescence remains unclear. The objective of this study is to investigate the influences of KT on the immunity of thymus in rats by detecting the apoptosis and the proliferation index (PI).Methods: We firstly established an aging rat model by subcutaneously injecting D- galactose (D-gal, 125mg/kg•BW) in the dorsal neck of Sprague Daly rats (SD rats); then the rats were divided into KT treatment groups (three groups for different doses of KT), aging model group (without KT treatment) and young control group. The rats in KT treatment groups were treated with different-dose KT and the key indices including the changes of the number of CD3+, CD4+ and CD8+ T lymphocyte subpopulations in peripheral blood, the apoptosis of thymus lymphocytes. Result: KT could increase the number of the peripheral CD3+, CD4+ and CD8+ T lymphocytes of the aging rats while decreased the apoptotic rate of thymocytes and increased PI Index.


2021 ◽  
Author(s):  
Zheng Kang ◽  
Sijia Chen ◽  
Liwan Shi ◽  
Yipeng He ◽  
Xiang Gao

Abstract Background Before radiotherapy for breast cancer patients, the choice of three-dimensional conformal radiation therapy (3D-CRT) and volumetric modulated arc therapy (VMAT) should be made. This study investigates the performance of two structural metrics in aiding the choice of 3D-CRT and VMAT plans in women undergoing left-sided whole breast radiotherapy. Materials and methods 119 patients previously treated with left-sided breast radiotherapy (61 3D-CRT treatments and 58 VMAT treatments) from a single institution were retrospectively studied. Two structural metrics, which are cardiac intersetion (CI) index and pulmonary intersection (PI) index, were defined and the relationship between these metrics and dose of organs at risk (OARs) were evaluated. Two-tailed Student’s t-test was performed to compare patient characteristics between 3D-CRT and VMAT. Linear regressions were calculated to investigate the association between structural metrics and absorbed dose of heart and left lung, including MHD, V5, V30 of heart, and MLLD, V5, V10, V20, V30, V40 of left lung. Results The CI index was strongly correlated with the mean dose of heart (MHD) in 3D-CRT group and VMAT group, the linear regression formulas were MHD = 4826.59 ×CI Index + 310.48 (R = 0.857, F = 163.77, P = 0.000) in 3D-CRT plans and MHD = 1789.29×CI Index + 437.50 (R = 0.45, F = 14.23, P = 0.000) in VMAT plans, the intercept of these formulas was CI index = 4.2% and MHD = 512.33 cGy. The PI index demonstrated a strongly positive correlation with mean dose of left lung (MLLD) in 3D-CRT group and VMAT group as well, the linear regression formulas were MLLD = 2879.54×PI Index + 999.79 (R = 0.697, F = 55.86, P = 0.000) in 3D-CRT plans and MLLD = 1411.79×PI Index + 1091.88 (R = 0.676, F = 47.11, P = 0.000) in VMAT plans, the intercept of these formulas was PI index = 6.3% and MLLD = 1180.46 cGy. Conclusions CI index and PI index could serve as a practical tool of choosing either 3D-CRT or VMAT before the plan was generated. We recommend that VMAT plan is preferable when CI index is greater than 4.2% and PI index is greater than 14.6%, while 3D-CRT plan is the first choice in the opposite.


2021 ◽  
Vol 44 (1) ◽  
pp. 203-212
Author(s):  
Syed Ahtsham Ul Haq Bokhary ◽  
Adnan

Abstract The Wiener index, due to its many applications is considered to be one of very important distance-based index. But the Padmaker-Ivan (PI) index is kind of the only distance related index linked to parallelism of edges. The PI index like other distance related indices has great disseminating power. The index was firstly investigated by Khadikar et al. (2001), they have probed the chemical applications of the PI index. They proved that the proposed PI index correlates highly with the physicochemical properties and biological activities of a large number of diverse and complex chemical compounds and the Wiener and Szeged indices. Recently, the vertex Padmarkar-Ivan (PIv) index of a chemical graph G was introduced as the sum over all edges uv of a molecular graph G of the vertices of the graph that are not equidistant to the vertices u and v. In this paper, the vertex PIv index of certain triangular tessellation are computed by using graph-theoretic analysis, combinatorial computing, and edge-dividing technology.


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