spread area
Recently Published Documents


TOTAL DOCUMENTS

89
(FIVE YEARS 9)

H-INDEX

14
(FIVE YEARS 0)

Author(s):  
Siba Prasad Mishra ◽  
Chandan Kumar ◽  
Abhisek Mishra ◽  
Saswat Mishra ◽  
Ashish Patel

Reservoir sedimentation is a regular process and sequential path of sedimentation in reservoirs comprising of erosion, entrainment, transference, deposition and compaction of dregs carried into artificial lakes formed behind the dams. India houses 5334 large dams in function (2329 numbers before 1980) and 411 dams are in pipeline. The Rengali dam, functioned from 1984, that traps 50% of the total sediment load of the Brahmani River continues to thwart the growth and buffering of the Brahmani delta. Remote sensing (RS) and Geographical Information System (GIS) have emerged as powerful tools to create spatial inventory on Hydro-Bio-geo resources and the state of the environment. The RS/GIS and process-based modelling employed in spatial and dynamic assessment of loss in live storage of the reservoir by developing contour, aspect and slope map by using data received from LANDSAT sources. The sedimentation of the Rengali reservoir (functional from 1984) studied for three decades 1990-2000; 2000-2010 and 2010- 2020 by constructing contour, aspect and water spread area maps by using web based data (satellite downloads). The web based water spread area data analysed by GIS tool for integration, spatial analysis, and visual presentations. The results revealed that the decadal rate of sedimentation of Rengali reservoir is reducing with age. An appropriate reservoir operation and management system as per defined protocols considering sediment related problems is essential for controlling the ageing processes that may diminish the safety and shorten the reservoir life.


2021 ◽  
Author(s):  
Sanjay Kumar Kureel ◽  
Shatarupa Sinha ◽  
Purboja Purkayastha ◽  
Sarah Barretto ◽  
Abhijit Majumder

The microenvironment of human mesenchymal stem cells (hMSCs) regulates their self-renewal and differentiation properties. Previously it was shown that hMSCs remained quiescent on soft (0.25 kPa) polyacrylamide (PA) gels but re-entered into cell cycle on a stiff (7.5 kPa) gel. However, how cells behave on intermediate stiffness and what intracellular factors transmit mechanical changes to cell interior thereby regulating cell cycle remained unknown. In this work we demonstrated that PA gels between 1 and 5 kPa act as a mechanical switch in regulating cell cycle of hMSCs. By experiments on cell-cycle exit and re-entry, we found that hMSCs demonstrated a sharp transition from quiescence to proliferation between 1 and 5 kPa. Further studies with ROCK inhibitor Y-27632 revealed that contractile proteins, but not cell spread area, accounts for the sensitivity of hMSCs towards substrate stiffness and hence correlates with their changes in cell cycle. These observations therefore suggest that substrate stiffness regulates hMSC proliferation through contractile forces as generated by cellular contractile proteins in a unique pattern which is distinct from other cell types as studied.


2021 ◽  
Author(s):  
Malancha Ta ◽  
Ankita Sen

Mesenchymal stem cell (MSC)-based cellular therapy gets compromised as adverse microenvironmental conditions like nutrient deprivation, ischemia, hypoxia affect migration and engraftment, in addition to viability, of MSCs at the target site post transplantation. To improve the treatment efficacy, it is critical to identify factors involved in regulating migration and adhesion of MSCs under such microenvironmental stress conditions. In our study, we observed that Wharton's jelly-MSCs (WJ-MSCs) exhibited increase in cell spread area and adhesion with reduction in cellular migration under serum starvation. The changes in adhesion and migration characteristics were accompanied by extensive stress fibre formation and altered ECM gene expression with notable induction in vitronectin (VTN) expression and reduction in MMP-1 expression. Molecular and phenotypic correlative studies advocated the possible role of VTN and not MMP-1, in regulating adhesion and migration of WJ-MSCs. NF-kb was found to be the positive regulator of VTN expression while ERK pathway regulated it negatively. Further investigation with inhibition of these signalling pathways or VTN knockdown studies under serum starvation established the correlation between increase in VTN expression and increased cellular adhesion with corresponding reduction in migration. VTN knockdown under serum starvation also led to reduction in actin stress fibre along with reversal in expression of several ECM genes. Additionally, VTN induction being absent in hypoxia-treated WJ-MSCs, the hypoxic cells showed no significant change in the adhesion and migration properties. However, when VTN expression was induced under hypoxia by ERK pathway inhibition, similar increase in cell spread area and adhesion was observed. Our study thus highlights VTN as a factor which is induced under serum starvation stress and possibly affects the adhesion and migration properties of WJ-MSCs.


2021 ◽  
Author(s):  
Kevin M Beussman ◽  
Molly Y Mollica ◽  
Andrea Leonard ◽  
Jeffrey Miles ◽  
John Hocter ◽  
...  

Measuring the traction forces produced by cells provides insight into their behavior and physiological function. Here, we developed a technique (dubbed 'black dots') that microcontact prints a fluorescent micropattern onto a flexible substrate to measure cellular traction forces without constraining cell shape or needing to detach the cells. To demonstrate our technique, we assessed human platelets, which can generate a large range of forces within a population. We find platelets that exert more force have more spread area, are more circular, and have more uniformly distributed F-actin filaments. As a result of the high yield of data obtainable by this technique, we were able to evaluate multivariate mixed effects models with interaction terms and conduct a clustering analysis to identify clusters within our data. These statistical techniques demonstrated a complex relationship between spread area, circularity, F-actin dispersion, and platelet force, including cooperative effects that significantly associate with platelet traction forces.


2021 ◽  
Vol 21 (2) ◽  
pp. 54-60
Author(s):  
E Behanova ◽  
H Pedan ◽  
P Hanzel ◽  
A Hajtman ◽  
V. Calkovsky

Abstract In head and neck cancers the occurrence of nodal metastases is the most important prognostic factor. Their early diagnosis is crucial for proper treatment. Detection of early metastases is still very difficult. Predictive diagnostic methods such as the sentinel lymph node detection is limited by the occurrence of skip metastases. At our Clinic we prefer a selective neck dissection based on a surgical treatment of predilected lymphatic spread area for each type of head and neck tumor with a preservation of non-lymphatic structures of the neck. The main objective of this article is to analyze the distribution of neck metastases and to study the frequency of skip metastases in head and neck cancer.


2021 ◽  
Vol 47 (2) ◽  
pp. 362-370
Author(s):  
Kashyap Shwetmala ◽  
H.N. Chanakya ◽  
T.V. Ramachandra

Developing country municipal solid waste management is complex, managed by multiple institutions, prone to socio-political disruptions and often requires frequent and rapid estimates of good functioning. Estimating the quantity, composition and status of municipal solid waste found at unauthorized dump sites helps in diagnosis and in improving solid waste management system. The objective of this study was to find occurrences of unauthorized dump sites and to determine quantity, area, height of dumps, waste density and waste composition at these sites. A total of 452 locations were identified and quantification of solid wastes was carried out at 268 locations by determining waste spread area, measuring dump height and density by multiple techniques. Mixed dumped wastes at site was physically segregated into twelve waste categories (organic fraction, plastic, construction debris, paper, cloth, glass, leather, metal, rubber, biomedical waste, burnt waste and industrial wastes). It was estimated about 213310 Mg of wastes were dumped in 452 unauthorized dump sites. The composition of waste dumped in unauthorized sites have 41.3% of construction debris followed by 28.9% of organic waste and other fractions constituted the remaining. The waste composition at dump site suggests less efficient recycling systems and the possible direction for the system improvements.


2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Yong Kwan Noh ◽  
Sung Won Kim ◽  
Ik-Hwan Kim ◽  
Kwideok Park

Abstract Background Extracellular matrix (ECM) has a profound effect on cell behaviors. In this study, we prepare a decellularized human nasal septal chondrocyte (NSC)-derived ECM (CHDM), as a natural (N-CHDM) or soluble form (S-CHDM), and investigate their impact on NSCs differentiation. Methods N-CHDM, S-CHDM were obtained from NSC. To evaluate function of NSC cultured on each substrate, gene expression using chondrogenic marker, and chondrogenic protein expression were tested. Preconditioned NSCs-loaded scaffolds were transplanted in nude mice for 3 weeks and analyzed. Results When cultivated on each substrate, NSCs exhibited similar cell spread area but showed distinct morphology on N-CHDM with significantly lower cell circularity. They were highly proliferative on N-CHDM than S-CHDM and tissue culture plastic (TCP), and showed more improved cell differentiation, as assessed via chondrogenic marker (Col2, Sox9, and Aggrecan) expression and immunofluorescence of COL II. We also investigated the effect of NSCs preconditioning on three different 2D substrates while NSCs were isolated from those substrates, subsequently transferred to 3D mesh scaffold, then cultivated them in vitro or transplanted in vivo. The number of cells in the scaffolds was similar to each other at 5 days but cell differentiation was notably better with NSCs preconditioned on N-CHDM, as assessed via real-time q-PCR, Western blot, and immunofluorescence. Moreover, when those NSCs-loaded polymer scaffolds were transplanted subcutaneously in nude mice for 3 weeks and analyzed, the NSCs preconditioned on the N-CHDM showed significantly advanced cell retention in the scaffold, more cells with a chondrocyte lacunae structure, and larger production of cartilage ECM (COL II, glycosaminoglycan). Conclusions Taken together, a natural form of decellularized ECM, N-CHDM would present an advanced chondrogenic potential over a reformulated ECM (S-CHDM) or TCP substrate, suggesting that N-CHDM may hold more diverse signaling cues, not just limited to ECM component.


2021 ◽  
Vol 275 ◽  
pp. 02013
Author(s):  
Qi Hui Lu ◽  
Qian Hong Tan

Supported by the agricultural technology, the intelligent agricultural development is flourishing. However, due to the high technology cost and investment risk, intelligent agriculture in China is still in the exploration stage. This article designs the appropriate cost sharing mechanism under the two-stage supply chain system, which composes of a farmer, a core enterprise and a commercial bank. With the comparison between commercial bank financing model and the buyer guarantees financing model, this paper researches the optimal decisions of supply chain members and the influence of the cost-sharing ratio, technical input gain effect and the buyer guarantees ratio. The results show that the profit will increase with the add of technical input gain effect. Besides, only under certain conditions, cost sharing is valuable to each member. Finally, numerical examples show existing an optimal interest rate spread area that all members would benefit from the buyer guarantee financing model.


2020 ◽  
Author(s):  
Yong Kwan Noh ◽  
Sung Won Kim ◽  
Ik Hwan Kim ◽  
Kwideok Park

Abstract Background Extracellular matrix (ECM) has a profound effect on cell behaviors. In this study, we prepare a decellularized human nasal septal chondrocyte (NSC)-derived ECM (CHDM), as a natural (N-CHDM) or soluble form (S-CHDM), and investigate their impact on NSCs differentiation. Methods N-CHDM, S-CHDM were obtained from NSC. To evaluate function of NSC cultured on each substrate, gene expression using chondrogenic marker, and chondrogenic protein expression were tested. Preconditioned NSCs-loaded scaffolds were transplanted in nude mice for 3 weeks and analyzed. Results When cultivated on each substrate, NSCs exhibited similar cell spread area but showed distinct morphology on N-CHDM with significantly lower cell circularity. They were highly proliferative on N-CHDM than S-CHDM and tissue culture plastic (TCP), and showed more improved cell differentiation, as assessed via chondrogenic marker (Col2, Sox9, and Aggrecan) expression and immunofluorescence of COL II. We also investigated the effect of NSCs preconditioning on three different 2D substrates while NSCs were isolated from those substrates, subsequently transferred to 3D mesh scaffold, then cultivated them in vitro or transplanted in vivo. The number of cells in the scaffolds was similar to each other at 5 days but cell differentiation was notably better with NSCs preconditioned on N-CHDM, as assessed via real-time q-PCR, Western blot, and immunofluorescence. Moreover, when those NSCs-loaded polymer scaffolds were transplanted subcutaneously in nude mice for 3 weeks and analyzed, the NSCs preconditioned on the N-CHDM showed significantly advanced cell retention in the scaffold, more cells with a chondrocyte lacunae structure, and larger production of cartilage ECM (COL II, glycosaminoglycan). Conclusion Taken together, a natural form of decellularized ECM, N-CHDM would present an advanced chondrogenic potential over a reformulated ECM (S-CHDM) or TCP substrate, suggesting that N-CHDM may hold more diverse signaling cues, not just limited to ECM component.


Sign in / Sign up

Export Citation Format

Share Document