Effect of Retention Time of Neutrophils in Alveolar Capillaries on Increase in Their Concentration in the Capillary Network

2007 ◽  
Author(s):  
A. Shirai ◽  
T. Hayase
Keyword(s):  
Retention Time ◽  
Concentration Ratio ◽  
Systemic Circulation ◽  
Capillary Network ◽  
Dominant Factor ◽  
Numerical Result ◽  
Cell Property ◽  
Capillary Bed ◽  
The Relationship ◽  
Alveolar Capillary

It is said that neutrophils, a kind of leukocytes, can be retained in pulmonary alveolar capillary bed, even in normal lungs, resulting in higher concentration than in systemic circulation due to their relatively low deformability, and the concentrated neutrophils help the lung to effectively eliminate the enemies invading from outer air. The authors have developed a model to simulate the flow of neutrophils through an alveolar capillary network, considering the cells’ low deformability as the dominant factor for the retention. Flow of a suspension of neutrophils in plasma through a simplified lattice alveolar capillary network model was numerically simulated to investigate the effect of the retention on the increase in the concentration ratio of the cells between in the network and in the suspension. The numerical result showed that the ratio was lower than the experimentally obtained value. Other possible factors to influence the cell’s retention time are friction and adhesion of the cell on the endothelium. In the last study, effect of the retention time of the cells in individual capillary segments on the increase in the concentration ratio was investigated to suggest the ratio may have an upper limit no matter how long the retention time is extended. In this paper, the authors investigated the contribution of various parameters which affect transit time of a neutrophil through a single capillary segment to the relationships between the retention time and the concentration ratio. Finally, it was shown that the number of cells in the network increased to approach a finite value as the increase in the coefficient, independent of the cell property, concentration of the cells in the suspension or the capillary shape. Transition of the relationship was changed with the parameters.

Effect of Neutrophils Retention Time in Capillaries on Increase in Their Concentration in a Lattice Capillary Network Model

2007 ◽  
Author(s):  
Atsushi Shirai ◽  
Toshiyuki Hayase
Keyword(s):  
Immune System ◽  
Network Model ◽  
Host Defense ◽  
Retention Time ◽  
Systemic Circulation ◽  
Capillary Network ◽  
Know How ◽  
Pulmonary Capillary ◽  
And Behavior ◽  
Normal Lungs

Neutrophils are known as the most popular cells in leukocytes, and play important roles in immune system. They are retained in pulmonary capillary network even in normal lungs, causing higher concentration than in systemic circulation due to their low deformability [1]. The lungs can be a route for pathogenic substances to invade the host, since thickness of septa which separates blood and outer air is extremely thin. However, the highly concentrated neutrophils are thought to be effectively recruited to the sites of inflammation for the host defense. Therefore, it is essential to know how neutrophils flow in pulmonary capillary microvasculature for the understanding of their functions and behavior in immune system.

LOYALITAS PELANGGAN: PERAN CITRA MEREK DAN KUALITAS PRODUK

2019 ◽  
Vol 4 (3) ◽  
pp. 391-400
Author(s):  
Machmed Tun Ganyang
Keyword(s):  
Regression Analysis ◽  
Product Quality ◽  
Customer Loyalty ◽  
Brand Image ◽  
Dominant Factor ◽  
Consumer Loyalty ◽  
The Relationship

This study aims to examine the relationship between brand image and product quality on customer loyalty in sports products. Data were collected through a questionnaire of 68 respondents. Through regression analysis, the results show that brand image and quality can explain variations in consumer loyalty with the brand image as a dominant factor. This finding implies that producers can increase consumer loyalty by enhancing brand image. Companies need to think about how to develop key messages so that consumers can clearly understand the position of the product. The unique aspects of the product need to be improved to create a special impression on the customer. Keywords: brand image, produk quality, customer loyalty

scholarly journals Overland Flow Resistance Law under Sparse Stem Vegetation Coverage

Water ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1657
Author(s):  
Jingzhou Zhang ◽  
Shengtang Zhang ◽  
Si Chen ◽  
Ming Liu ◽  
Xuefeng Xu ◽  
...  
Keyword(s):  
Flow Resistance ◽  
Overland Flow ◽  
Vegetation Coverage ◽  
Dominant Factor ◽  
Roughness Coefficient ◽  
Hydraulic Parameters ◽  
Slope Condition ◽  
Manning Roughness ◽  
The Relationship ◽  
Manning Roughness Coefficient

To explore the characteristics of overland flow resistance under the condition of sparse vegetative stem coverage and improve the basic theoretical research of overland flow, the resistance characteristics of overland flow were systematically investigated under four slope gradients (S), seven flow discharges (Q), and six degrees of vegetation coverage (Cr). The results show that the Manning roughness coefficient (n) changes with the ratio of water depth to vegetation height (h/hv) while the Reynolds number (Re), Froude number (Fr), and slope (S) are closely related to vegetation coverage. Meanwhile, h/hv, Re, and Cr have strong positive correlations with n, while Fr and S have strong negative correlations with n. Through data regression analysis, a power function relationship between n and hydraulic parameters was observed and sensitivity analysis was performed. It was concluded that the relationship between n and h/hv, Re, Cr, Q, and S shows the same law; in particular, for sparse stem vegetation coverage, Cr is the dominant factor affecting overland flow resistance under zero slope condition, while Cr is no longer the first dominant factor affecting overland flow resistance under non-zero slope condition. In the relationship between n and Fr, Cr has the least effect on overland flow resistance. This indicates that when Manning roughness coefficient is correlated with different hydraulic parameters, the same vegetation coverage has different effects on overland flow resistance. Therefore, it is necessary to study overland flow resistance under the condition of sparse stalk vegetation coverage.

Breeding and milk quality

1984 ◽  
Vol 9 ◽  
pp. 27-34
Author(s):  
J. R. Mulholland
Keyword(s):  
Dairy Cattle ◽  
Milk Quality ◽  
Dominant Factor ◽  
Probability Curve ◽  
Animal Remains ◽  
Normal Probability ◽  
Payment Schemes ◽  
Long Time ◽  
High Production ◽  
The Relationship

SUMMARYThe broad principles of animal breeding are outlined and the ‘normal-probability curve’ is used to illustrate how progress should be made in improving the genetic merit of dairy cattle. The importance of genetically correlated responses is discussed, together with the need to test progeny. The way in which genetic improvement accumulates in dairy cattle is described and the need to use high-production sires with reliable proofs is stressed. Present and proposed milk-quality payment schemes require that selection should be based on the yield of recorded solids as the best indicator of total solids. As cattle breeding involves a long time-scale, it is not always possible to take into account short-term changes in the value of milk constituents. The effect of changing values upon the ranking of bulls is small and, for the foreseeable future, the use of the weight of recorded solids, i.e. the weight of fat plus the weight of protein, as the selection factor, is likely to maximize progress. The relationship between functional type and herd life is examined. It is concluded that there is no obvious relationship between type and herd life; yield is the dominant factor in determining the length of time an animal remains in the herd. Any breeding programme should therefore place maximum emphasis on production.

The relationship between apparent retention time in the rumen, voluntary intake, and apparent digestibility of legume and grass diets in sheep

1973 ◽  
Vol 24 (6) ◽  
pp. 889 ◽  
Author(s):  
RF Thornton ◽  
DJ Minson
Keyword(s):  
Organic Matter ◽  
Retention Time ◽  
Daily Intake ◽  
Organic Matter Content ◽  
Matter Content ◽  
Apparent Digestibility ◽  
Jaw Movements ◽  
Digestible Organic Matter ◽  
Voluntary Intake ◽  
The Relationship

Eight grasses and six legumes were fed ad libitum at hourly intervals to wethers fitted with large rumen fistulas to determine voluntary intake, apparent digestibility, and the apparent retention time of organic matter in the rumen, as well as the quantity of rumen digesta and the organic matter content of the rumen digesta. The voluntary intake of legumes was 28% higher than that of equally digestible grasses. This difference was caused by a shorter retention time (17%) and a higher amount of organic matter (14%) in the rumen digesta from legume diets than from grass diets. The weight of wet digesta in the rumen of sheep fed on legumes was 7% lower than from those fed on grass. Neither the quantity of digesta nor the quantity of organic matter in the rumen was related to the voluntary intake, digestibility, or retention time of organic matter in the rumen. Number of jaw movements each day and rate of cotton thread digestion were not related to the retention time of the diets either. Daily intake of digestible organic matter (DOMI, g/day) was closely correlated with retention time (RTOM, hr) for the feeds in this study (r = –0.93) and the same relation applied to both temperate and tropical feeds, viz. DOMI = 1276–50.7 RTOM (r=0.96) Differences in voluntary intake between grasses and legumes were attributed to differences in retention time and the density to which the food was packed in the rumen.

Stem pressure at the origin of intracranial collateral vessels

1992 ◽  
Vol 262 (4) ◽  
pp. H1294-H1297
Author(s):  
G. M. Greene ◽  
M. G. Muhonen ◽  
K. N. Detwiler ◽  
D. D. Heistad ◽  
C. M. Loftus
Keyword(s):  
Regional Cerebral Blood Flow ◽  
Autologous Blood ◽  
Regional Cerebral Blood ◽  
Anesthetized Dogs ◽  
Capillary Bed ◽  
Vascular Channels ◽  
Collateral Vessels ◽  
The Relationship ◽  
Large Vessels ◽  
Rcbf Measurement

The relationship between pressure at the functional site of origin of intracranial collateral channels (Pstem) and systemic pressure allows an estimation of the size of vascular channels from which collateral vessels originate. In this study, Pstem was determined in anesthetized dogs. A branch of the middle cerebral artery was perfused through a closed system with autologous blood. Tissues with regional cerebral blood flow (rCBF) less than or equal to 10 ml.100 g-1.min-1 (collateral-dependent zone) were identified using radioactive microspheres. Sequential injections of nonradioactive microspheres were made into the cannulated vessel to progressively occlude the terminal capillary bed. Injection of nonlabeled spheres was terminated when backpressure no longer increased, and the final rCBF measurement was made. There was a linear relationship between backpressure and flow to the collateral-dependent tissues. When rCBF within these tissues was zero, the corresponding value for backpressure (Pstem) was 79 +/- 4% (mean +/- SD) of mean arterial pressure. The high value for Pstem suggests that cerebral collateral channels arise in part from large vessels.

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