aggregation index
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Biology ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 78
Author(s):  
Shehwaz Anwar ◽  
Ravindra Raut ◽  
Mohammed A. Alsahli ◽  
Ahmad Almatroudi ◽  
Hani Alfheeaid ◽  
...  

This study investigated the health-promoting activities of methanolic extracts of Ajwa date seed and fruit pulp extracts through in vitro studies. These studies confirmed potential antioxidant, anti-hemolytic, anti-proteolytic, and anti-bacterial activities associated with Ajwa dates. The EC50 values of fruit pulp and seed extracts in methanol were reported to be 1580.35 ± 0.37 and 1272.68 ± 0.27 µg/mL, respectively, in the DPPH test. The maximum percentage of hydrogen peroxide-reducing activity was 71.3 and 65.38% for both extracts at 600 µg/mL. Fruit pulp and seed extracts inhibited heat-induced BSA denaturation by 68.11 and 60.308%, heat-induced hemolysis by 63.84% and 58.10%, and hypersalinity-induced hemolysis by 61.71% and 57.27%, and showed the maximum anti-proteinase potential of 56.8 and 51.31% at 600 μg/mL, respectively. Seed and fruit pulp inhibited heat-induced egg albumin denaturation at the same concentration by 44.31 and 50.84%, respectively. Ajwa seed showed minimum browning intensity by 63.2%, percent aggregation index by 64.2%, and amyloid structure by 63.8% at 600 μg/mL. At 100 mg/mL, Ajwa seed extract exhibited good antibacterial activity. Molecular docking analysis showed that ten active constituents of Ajwa seeds bind with the critical antioxidant enzymes, catalase (1DGH) and superoxide dismutase (5YTU). The functional residues involved in such interactions include Arg72, Ala357, and Leu144 in 1DGH, and Gly37, Pro13, and Asp11 in 5YTU. Hence, Ajwa dates can be used to develop a suitable alternative therapy in various diseases, including diabetes and possibly COVID-19-associated complications.


Author(s):  
R. Verma ◽  
P. K. Garg

Abstract. Urban planning in smart cities needs to be done in a “Smart” way. One way is to analyze the urbanisation pattern by spatio-temporal change detection techniques. Classified data such as, for years 1985, 1995 and 2005 Decadal Land use data for India and for year 2015, Copernicus Global Land service Dynamic Land Cover layers (CGLS-LC100 products) are used to perform multi-temporal analysis of the 11 smart cities of Uttar Pradesh state of India namely "Agra", "Aligarh", "Bareilly", "Jhansi", "Kanpur", "Lucknow", "Moradabad", "Prayagraj", "Rampur", "Saharanpur" and "Varanasi". Dynamics of Urban expansion are studied utilizing concepts of Landscape Metrics calculated by FRAGSTATS and also Shannon’s Entropy Values (Hn) over the 11 smart cities. Largest Patch Index (LPI), Landscape Shape Index (LSI), Aggregation Index (AI) and Mean Euclidean Nearest Neighbor Distance (ENN_MN) are metrics used to characterize urbanisation. Results indicate rise in value of LSI over the years from 1985 and with sudden increase in year 2015 for Built-up patches, corroborating more complexity in shapes of Built-up patches in all 11 cities. Kanpur, showing large values of LPI indicates the sudden increase of Built-up land use class over the years. The decreasing value of ENN_MN over the years indicates less centrality for built-up pixels in urbanisation. AI is unchanged for Built-up patches for 1985–1995 but decrease in year 2015 indicates less compactness which is due to dispersion of built-up pixels. High values of Hn over the years indicating dispersion of urbanisation in all 11 smart cities except Agra, also validates results.


Author(s):  
Jiale Liang ◽  
Sipei Pan ◽  
Wanxu Chen ◽  
Jiangfeng Li ◽  
Ting Zhou

The booming population and accelerating urbanization in the Huaihe River Basin have sped up the land use transformation and the cultivated land fragmentation (CLF), seriously impeded the advancement of agricultural modernization, and threatened regional stability and national food security as well. The analysis of CLF degree and its spatiotemporal distribution characteristics, along with the influencing factors in the Huaihe River Basin, is of great significance for promoting the intensive and efficient utilization of cultivated land resources and maintaining food security. Previous studies lack the measurement and cause analysis of CLF in Huaihe River Basin. To bridge the gap, this study introduces Fragstats4.2 and ArcGIS10.3 to analyze the spatiotemporal characteristics of CLF in county units in the Huaihe River Basin from 2000 to 2018 through the Lorentz curve, entropy method, and spatial auto-correlation method while the causes of the spatiotemporal differentiation of CLF in the basin were explored with the help of a geographic detector. The results show that the spatial distribution of cultivated land in the Huaihe River Basin is relatively balanced, and the Gini coefficients of cultivated land from 2000 to 2018 were 0.105, 0.108, and 0.113, respectively. More than 56% of the counties in the basin have a location entropy greater than 1. the percentage of landscape, area-weighted mean patch area, patch cohesion index, and aggregation index decrease year by year while the patch density and splitting index show an upward trend. The landscape pattern of cultivated land is highly complex, and the overall fragmentation degree is increasing. The county distribution pattern of the CLF degree with random and agglomeration is generally stable. The spatiotemporal differentiation of CLF in the Huaihe River Basin is affected by multiple factors, among which the influences of the normalized difference vegetation index, per capita cultivated land area, and intensity of human activity obviously stronger than other factors, and the contribution rate of the factors reached more than 0.4. The interaction effect among the factors is stronger than that of single factor, with dual-factor enhancement and nonlinear enhancement dominating. The results of this study have important implications for optimizing the agricultural structure in the Huaihe River Basin and alleviating the CLF in important grain production areas.


Metabolites ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 886
Author(s):  
Alicja Szołna-Chodór ◽  
Bronisław Grzegorzewski

Glucose metabolism disorders contribute to the development of various diseases. Numerous studies show that these disorders not only change the normal values of biochemical parameters but also affect the mechanical properties of blood. To show the influence of glucose and poloxamer 188 (P188) on the mechanical properties of a red-blood-cell (RBC) suspension, we studied the aggregation of the cells. To show the mechanisms of the mechanical properties of blood, we studied the effects of glucose and poloxamer 188 (P188) on red-blood-cell aggregation. We used a model in which cells were suspended in a dextran 70 solution at a concentration of 2 g/dL with glucose and P188 at concentrations of 0–3 g/dL and 0–3 mg/mL, respectively. RBC aggregation was determined using an aggregometer, and measurements were performed every 4 min for 1 h. Such a procedure enabled the incubation of RBCs in solution. The aggregation index determined from the obtained syllectograms was used as a measure of aggregation. Both the presence of glucose and that of P188 increased the aggregation index with the incubation time until saturation was reached. The time needed for the saturation of the aggregation index increased with increasing glucose and P188 concentrations. As the concentrations of these components increased, the joint effect of glucose and P188 increased the weakening of RBC aggregation. The mechanisms of the observed changes in RBC aggregation in glucose and P188 solutions are discussed.


2021 ◽  
Vol 40 (4) ◽  
pp. 379-383
Author(s):  
Kateryna Kolesnykova ◽  
Galina Zadorozhna

Abstract Density variability of a population of the mollusk Brephulopsis cylindrica (Menke, 1828) was studied at a reclaimed site in the Nikopol manganese ore basin. This study was conducted on sod-lithogenic soil on grey-green clay. The samples were collected over 3 years, 3 times a year, on a regular grid. Lexis aggregation index (λ) and geostatistical tools were used to characterise spatial distribution of the mollusks. The correlation between the distribution of B. cylindrica and environmental factors was established using correlation analysis. Valid correlations were identified between distribution of the mollusk and variation of the fraction content in composition of structural aggregates of soil. Also, valid correlations were identified with plant species composition at the reclaimed site.


2021 ◽  
Author(s):  
Anna Dmowska ◽  
Tomasz Stepinski

Over the last several decades large U.S. cities became increasingly racially diverse. Understanding spatio-temporal dynamics of this significant social change and identifying its broad trends is important for numerous stakeholders. High resolution population grids, which recently become available for the entire conterminous U.S. and for three-time points from 1990 to 2010, are an ideal dataset for analyzing dynamics of racial diversity. Their value to diversity analysis has been already demonstrated at the level of the entire U.S. as well as at the level of an individual city.In this paper, we demonstrate their value for performing a survey aimed at synthesizing diversity dynamics from different cities in order to identify prevalent nationwide trends. Our survey consists of 41 large cities. 1990-2000-2010 snapshots of racial conditions at each city are provided by respective grids in which each cell is assigned one of nine possible diversity/dominant race categories. All cells with the same diversity label constitute a zone which we refer to as community and measure using a percentage of landscape (PLAND) and an aggregation index (AI) metrics. The inclusion of the AI metric makes it possible to determine not only whether a given community grows or shrinks but also whether it’s merging or fragmenting. We analyze spatio-temporal evolution of communities by tracking changes in the pairs of the values of these metrics. To simplify we categorize these changes into eight categories resulting in 64 possible change trajectories for each community. Trajectories are histogrammed to reveal the variety of scarcity of possible modes of change. Frequent trajectories are identified with broad trends. Eight such trends are identified, they represent the most prevalent racial dynamics in the U.S. during the decades of 1990-2010. Two trends correspond to the decay of whites-only and blacks-only communities. The remaining six trends correspond to the expansion of Hispanics, Asian, and racially diverse communities. Trends do not show regional dependence, they truly reflect profound social change occurring across the entire U.S.


2021 ◽  
Author(s):  
Jia-shuo Cao ◽  
Yu-qi Yang ◽  
Zheng-yu Deng ◽  
Yuan-dong Hu

Abstract Background Shennongjia is one of the most important ecological function areas and ecologically vulnerable zones in the world. With the rapid development of social economies, especially tourism, the ecological environment of Shennongjia has experienced profound changes. To describe an assessment method of ecological vulnerability, explain its application in Shennongjia, and propose optimization strategies to reduce the risk of ecosystem vulnerability and maintain regional ecological security and stability. Results (1) During the study period, the overall ecological vulnerability of Shennongjia is in a mild vulnerability level, exhibiting differentiation characteristics of high in the northeast and low in the southwest. High vulnerability zones are mainly distributed in the main towns and roads of Shennongjia. (2) The risk of ecological vulnerability of the entire region presents the characteristics of continuous decline. The ecological vulnerability composite index reaches the lowest value of 2.51 in 2018. (3) Land-use types, population density, and vegetation coverage are the main factors driving the evolution of ecological vulnerability. (4) A high level of coupling coordination exists between ecological vulnerability and landscape patterns, and the contribution of patch number and aggregation index to ecological vulnerability is substantial. Conclusions Analyses of the ecological vulnerability of Shennongjia shows that the entire region is in a mild vulnerability level. The extreme vulnerability risk of the northeast, south and southwest areas appears gradually, the vulnerability degree of the ecological environment shows polarization. The evolution of ecological environment in Shennongjia is the result of the interaction between human activities and natural environment. This study offers an effective way to assess ecological vulnerability and provides some strategies and guidance for improving ecological security.


Land ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 1167
Author(s):  
Shaohua Zhang ◽  
Kun Yang ◽  
Yuling Ma ◽  
Mingchan Li

Different urban growth patterns have various impact degrees on the urban ecosystem and environment. Impervious surface, a typical artificial construction can be used to reflect urban development. Therefore, this study estimated the spatiotemporal dynamics and expansion patterns of impervious surface area (ISA) in the Guangdong-Hong Kong-Macau (GHM) Bay Area since the establishment of the “Pearl River Delta economic zone” in 1994. Landsat time-series images were used to map the distribution of the ISA based on the combinational biophysical composition index (CBCI) and the bidirectional temporal filtering method (BTFM). The results indicated that the ISA in the GHM Bay Area drastically expanded from 569.23 km2 in 1994 to 10,200.53 km2 in 2016. In addition, the aggregation index (AI) value of the high-density area showed a decreasing trend from 1994 to 2004. However, the value of each landscape metric rapidly increased after 2004. Moreover, the mean ratio of the major axis to the minor axis of standard deviational ellipses from 1994 to 2004 was higher than that from 2005 to 2016. The results of landscape metrics and standard deviational ellipses indicated that the ISA growth pattern changed from edge expanding and leapfrogging to infilling and consolidation, with a turning point in 2004. Moreover, the principal sprawl orientation of the ISA was northwest to southeast before 2004. After 2004, the expansion direction of the ISA was less obvious due to the development pattern of infilling and consolidation. The rapid increase of GDP and population are the driving forces of urban expansion. However, topography and ecological protection policies as the limiting factors, which caused the infilling of the inner city and redevelopment of old urban areas.


2021 ◽  
pp. 039139882110525
Author(s):  
Akiko Oota-Ishigaki ◽  
Takashi Yamane ◽  
Daisuke Sakota ◽  
Ryo Kosaka ◽  
Osamu Maruyama ◽  
...  

Low-flow blood pumps rated under 1 L/min are emerging for new medical applications, such as hemofiltration in acute use. In those pumps, platelet adhesion and aggregation have to be carefully considered because of clogging risk in the filter part. To find an acceptable hemocompatibility that can be applied to low-flow centrifugal blood pump design, the platelet aggregation index, clogging on a micromesh filter, and the hemolysis index were investigated using a low-flow blood pump designed for hemofiltration use. We conducted circulation testing in vitro using fresh porcine blood and two centrifugal pumps with different impeller inlet shapes. The Negative Log Platelet Aggregation Threshold Index (NL-PATI), which reflects the ability of residual platelets to aggregate, and flow rate were measured during reflux for 60 min, and the Normalized Index of Hemolysis (NIH (g/20 min)) was calculated. In addition, blood cell clogging after reflux was observed on the micromesh filter by SEM, and the adhesion rate was calculated. Our results showed that the platelet clogging on the micromesh filter occurred when the average NL-PATI was greater than 0.28 and the average NIH (g/20 min) was greater than 0.01. In contrast, platelet clogging on the micromesh was suppressed when NL-PATI was less than 0.17 and the NIH (g/20 min) was less than 0.003. These values might be used as acceptable hemocompatibility of low-flow centrifugal blood pumps with suppressed platelet clogging for hemofiltration pumps.


Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2714
Author(s):  
Beata Csiszar ◽  
Gergely Galos ◽  
Simone Funke ◽  
Dora Kinga Kevey ◽  
Matyas Meggyes ◽  
...  

We investigated peripartum maternal red blood cell (RBC) properties in early-onset preeclampsia (PE). Repeated blood samples were taken prospectively for hemorheological measurements at PE diagnosis (n = 13) or during 26–34 weeks of gestation in healthy pregnancies (n = 24), then at delivery, and 72 h postpartum. RBC aggregation was characterized by M index (infrared light transmission between the aggregated RBCs in stasis) and aggregation index (AI—laser backscattering from the RBC aggregates). We observed significantly elevated RBC aggregation (M index = 9.8 vs. 8.5; AI = 72.9% vs. 67.5%; p < 0.001) and reduced RBC deformability in PE (p < 0.05). A positive linear relationship was observed between AI and gestational age at birth in PE by regression analysis (R2 = 0.554; p = 0.006). ROC analysis of AI showed an AUC of 0.84 (0.68–0.99) (p = 0.001) for PE and indicated a cutoff of 69.4% (sensitivity = 83.3%; specificity = 62.5%), while M values showed an AUC of 0.75 (0.58–0.92) (p = 0.019) and indicated a cutoff of 8.39 (sensitivity = 90.9% and specificity = 50%). The predicted probabilities from the combination of AI and M variables showed increased AUC = 0.90 (0.79–1.00) (p < 0.001). Our results established impaired microcirculation in early-onset PE manifesting as deteriorated maternal RBC properties. The longer the pathologic pregnancy persists, the more pronounced the maternal erythrocyte aggregation. AI and M index could help in the prognostication of early-onset PE, but further investigations are warranted to confirm the prognostic role before the onset of symptoms.


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