An asymmetrical model of the airways of the dog lung

1982 ◽  
Vol 52 (1) ◽  
pp. 21-26 ◽  
Author(s):  
K. Horsfield ◽  
W. Kemp ◽  
S. Phillips
Keyword(s):  
Input Impedance ◽  
Bronchial Tree ◽  
Physiological Variables ◽  
Resin Cast ◽  
Mean Diameter ◽  
The Difference ◽  
Asymmetrical Model ◽  
Number Of Branches

A resin cast of the bronchial tree of a dog was studied down to branches of 0.5-mm diameter. The branches were ordered, and the number of branches, mean diameter, and mean length of branches in each order were determined. The model was developed from these data with the property that delta, the difference in order between the two daughter branches at a bifurcation, is identical for all parent branches of a given order. This property facilitates the use of the model for the calculation of physiological variables such as input impedance (Fredberg and Hoenig, ASME J. Biomech. Eng. 100: 57–66, 1978), and the comparison of such results with those obtained from symmetrical models (Sidell and Fredberg, ASME J. Biomech. Eng. 100: 131–138, 1978).

scholarly journals PRODUCTIVITY Pueraria phaseoloides var. Javanica FERTILIZED WITH MANURE FROM CATTLE OFFERED CONCENTRATE CONTAINNING DIET SUPPLEMENTED WITH AMMONIUM SULFAT

Pastura ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 39
Author(s):  
Tjok. Istri Putri ◽  
Ni Putu Mariani
Keyword(s):  
Ammonium Sulfate ◽  
Weight Ratio ◽  
Dry Weight ◽  
Optimal Dosage ◽  
Pueraria Phaseoloides ◽  
Leaf Color ◽  
Randomized Design ◽  
Number Of Leaves ◽  
The Difference ◽  
Number Of Branches

This study aims to determine the optimal dosage of manure derived from cattle fed concentrated rations supplemented ammonium sulfate which can increase the productivity of Pueraria phaseoloidesvar .Javanica. The design used in this experiment was Completely Randomized Design (RAL) with 4 treatments and 5 replications. The four treatments were fertilized with doses of 10, 15, 20 and 25 tons / ha, respectively for the treatment of A, B, C and D, so overall there were 20 pot experiments. The study was conducted for 12 weeks. Observed variables were plant length, number of leaves, number of branches, dry weight (DW) of leaves, DW of stem DW, total BK, leaf color, leaf stem ratio (LSR) and leaf weight ratio”(LWR). The results showed that legumes treated A B, C and D produced high crop, leaf area, leaf color, LSR and LWR were not significantly different (P> 0.05). The treated legume C. resulted in a significantly higher leaf number than the treated legume A, B and D (P <0.05). The number of branches and DW leaves on legumes treated with C were significantly higher (P <0.05) than those receiving treatment A. and were not significantly different with legumes treated with B and D (P> 0.05). The DW of stem and total DW production from legume treated C were significantly higher with those treated with A and B (P <0.05) and the difference was not significant with those treated with D (P> 0.05). From the results of the study it can be concluded that legume treated with C or fertilized with manure derived from cattle fed concentrate containning diet supplemented ammonium sulfate at a dose of 20 tons / ha yield of leguminous productivity Peuraria phaseoloides var. javanica maximum. Keywords: manure, pueraria phaseoloides, productivity.

scholarly journals Productivity and profitability of peanut at various land suitability in North Lombok Regency of Nusa Tenggara Barat Province

2021 ◽  
Vol 6 (2) ◽  
pp. 99
Author(s):  
Ahmadi Suriadi ◽  
Fitria Zulhaedar ◽  
Moh. Nazam
Keyword(s):  
Arachis Hypogaea ◽  
Land Suitability ◽  
Cropping Pattern ◽  
Crop Varieties ◽  
Arachis Hypogaea L ◽  
Main Plot ◽  
The Difference ◽  
Number Of Branches ◽  
Plot Design ◽  
Suitable Land

Peanuts (Arachis hypogaea L.) are the second main commodity in the annual cropping pattern in lowland and dryland in North Lombok District of NTB Province. However, peanut productivity is still low, and it varies across regions, which might be due to the traditional crop management of farmers and the difference in land suitability classes. Effects of  crop varieties and land suitability on the peanut productivity have not been evaluated in the Region. Thus, this study aimed to evaluate the productivity and profitability of peanut varieties at various land classification in KLU NTB. The experiment was arranged in a Split Plot Design consisting of three classes of land suitability as main plot and six peanut varieties as sub-plot with three replications. The results showed that the land suitability classes have a significant effect on the agronomic variables of peanut varieties, including plant height, number of branches, number of pods and productivity. The highest peanut yield was obtained at suitable land class (S1), followed by moderately suitable land class (S2) and marginally suitable land class (S3) at 2.37 ton.ha-1, 2.08 ton.ha-1 and 1.71 ton.ha-1, respectively. Likewise, the R/C ratio follows a similar pattern to productivity in various land suitability classes. The highest yield (above 2 ton.ha-1) in each land suitability class was produced by Kelinci variety, followed by Tuban, Bima and Talam varieties. Those varieties have potential prospective to be developed in North Lombok Regency.

scholarly journals Evaluation of the best environment for the six-minute walk test

2015 ◽  
Vol 28 (3) ◽  
pp. 429-436
Author(s):  
Newton Santos de Faria Júnior ◽  
Cláudio Hiroshi Nakata ◽  
Luís Vicente Franco de Oliveira ◽  
Gaspar Rogério Chiappa ◽  
Gerson Cipriano Júnior
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Perceived Exertion ◽  
Low Cost ◽  
Walk Test ◽  
Physiological Variables ◽  
Six Minute Walk Test ◽  
The Mean ◽  
The Difference ◽  
Minute Walk

AbstractIntroduction The purpose of the six-minute walk test (6MWT) is to evaluate cardiopulmonary capacity using a low-cost test that is easy to administer, generally well tolerated by different populations and reflects one’s performance on activities of daily living. However, few studies have been conducted to determine the difference between performing the 6MWT indoors and outdoors.Objective The aim of the present study was to compare the distance covered on the 6MWT performed indoors and outdoors and evaluate the following physiological variables: heart rate, blood pressure and the subjective sensation of shortness of breath, using the Borg perceived exertion scale.Materials and methods A prospective, randomized, clinical trial was conducted involving eight healthy females not engaged in regular physical activity, with mean age 23.75 ± 1.67 years. Each subject performed the 6MWT indoors and outdoors with a 30-minute interval between tests. The order of the tests was determined randomly.Results The mean distance traveled was 578 ± 50.07 m on the outdoor trial and 579.95 ± 45.35 m on the indoor trial (p = 0.932). The mean physiological variables were 82.25 ± 11.02 bpm (indoors) versus 84.38 ± 9.42 bpm (outdoors) for heart rate, 121.88 ± 10.28 mmHg (indoors)versus 118.75 ± 19.40 mmHg (outdoors) for systolic blood pressure, 81.88 ± 9.74 mmHg (indoors) versus 80.50 ± 7.89 mmHg (outdoors) for diastolic blood pressure and a mean score of 12 on the perceived exertion score in both environments.Conclusions The present data demonstrate no differences in the distance walked on the 6MWT or the physiologic variables of participants between the indoor and outdoor trials.

scholarly journals A Vectorial Tree Distance Measure

2021 ◽  
Author(s):  
Avner Priel ◽  
Boaz Tamir
Keyword(s):  
Phylogenetic Trees ◽  
Distance Measure ◽  
Lexicographic Order ◽  
Distance Measures ◽  
Tree Distance ◽  
Hierarchical Trees ◽  
Distance Vector ◽  
The Difference ◽  
Number Of Branches

Abstract A vectorial distance measure for trees is presented. Given two trees, we align the trees from their centers outwards, starting from the root-branches, to make the next level as similar as possible. The algorithm is recursive; condition on the alignment of the root-branches we align the sub-branches, thereafter each alignment is conditioned on the previous one. We define a minimal alignment under a lexicographic order which follows the intuition that the differences between the two trees closer to their cores dominate their differences at a higher level. Given such a minimal alignment, the difference in the number of branches calculated at any level defines the entry of the distance vector at that level. We compare our algorithm to other well-known tree distance measures in the task of clustering sets of phylogenetic trees. We use the TreeSimGM simulator for generating stochastic phylogenetic trees. The vectorial tree distance can successfully separate symmetric from asymmetric trees, and hierarchical from non-hierarchical trees.

scholarly journals Airway Transmural Pressures in an Airway Tree During Bronchoconstriction in Asthma

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Tilo Winkler
Keyword(s):  
Experimental Studies ◽  
Bronchial Tree ◽  
Relative Increase ◽  
Transmural Pressure ◽  
Dynamic Hyperinflation ◽  
Airway Narrowing ◽  
Wilson Model ◽  
Airway Tree ◽  
The Difference ◽  
The Individual

Airway transmural pressure in healthy homogeneous lungs with dilated airways is approximately equal to the difference between intraluminal and pleural pressure. However, bronchoconstriction causes airway narrowing, parenchymal distortion, dynamic hyperinflation, and the emergence of ventilation defects (VDefs) affecting transmural pressure. This study aimed to investigate the changes in transmural pressure caused by bronchoconstriction in a bronchial tree. Transmural pressures before and during bronchoconstriction were estimated using an integrative computational model of bronchoconstriction. Briefly, this model incorporates a 12-generation symmetric bronchial tree, and the Anafi and Wilson model for the individual airways of the tree. Bronchoconstriction lead to the emergence of VDefs and a relative increase in peak transmural pressures of up to 84% compared to baseline. The highest increase in peak transmural pressure occurred in a central airway outside of VDefs, and the lowest increase was 27% in an airway within VDefs illustrating the heterogeneity in peak transmural pressures within a bronchial tree. Mechanisms contributing to the increase in peak transmural pressures include increased regional ventilation and dynamic hyperinflation both leading to increased alveolar pressures compared to baseline. Pressure differences between intraluminal and alveolar pressure increased driven by the increased airway resistance and its contribution to total transmural pressure reached up to 24%. In conclusion, peak transmural pressure in lungs with VDefs during bronchoconstriction can be substantially increased compared to dilated airways in healthy homogeneous lungs and is highly heterogeneous. Further insights will depend on the experimental studies taking these conditions into account.

Interdependence of regional expiratory flow

1985 ◽  
Vol 59 (6) ◽  
pp. 1924-1928 ◽  
Author(s):  
T. A. Wilson ◽  
J. J. Fredberg ◽  
J. R. Rodarte ◽  
R. E. Hyatt
Keyword(s):  
Lung Volume ◽  
Regional Differences ◽  
Vital Capacity ◽  
Maximum Flow ◽  
Bronchial Tree ◽  
Lung Compliance ◽  
Junction Flow ◽  
Expiratory Flow ◽  
The Difference ◽  
Limiting Pressure

Flows from different lung regions interact at the junctions of the bronchial tree, and flow from each region depends on the driving pressures for other regions. At each junction, flow from the region with the higher driving pressure is favored. As a result there is a limit on the difference in alveolar pressures that can develop during expiratory flow from a lung with regional differences in lung compliance and airway resistance. The limiting pressure difference is smaller for lower flow. A nonuniform lung therefore empties more uniformly if it empties slowly, and maximum flow at low lung volume may be greater than it would be at the same lung volume during a maximal expiratory vital capacity maneuver.

Embryonic and larval development of the brown wrasse Labrus merula (Pisces: Labridae)

1999 ◽  
Vol 79 (2) ◽  
pp. 327-332 ◽  
Author(s):  
J. Dulčić ◽  
V. Kožul ◽  
M. Kraljević ◽  
B. Skaramuca ◽  
B. Glamuzina ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Larval Development ◽  
Incubation Period ◽  
Yolk Sac ◽  
The Other ◽  
Mean Diameter ◽  
The Difference ◽  
Labrus Bergylta ◽  
Embryonic And Larval Development ◽  
Labrid Species

In March 1997 one male and one female brown wrasse Labrus merula spawned spontaneously in aquaria conditions. Eggs were incubated at ambient temperature, salinity, oxygen and pH. The development of the eggs, yolk-sac larvae and larvae is described and illustrated with particular emphasis on features of practical value for identification of specimens from plankton. The ripe egg of brown wrasse is a typical labrid egg with a mean diameter of 0.93±0.05 mm. The incubation period was 106 h 45 min at a mean temperature of 14.3°C. Newly hatched yolk-sac larvae were 3.8±0.02 mm, while the yolk-sac was resorbed when larvae reached 4.68±0.15 mm in total length. Some characteristics which may be useful for identification are described and compared with some other labrid yolk-sac larvae and larvae. The length of newly hatched yolk-sac larvae of brown wrasse was significantly larger (t-test, P<0.05) than those of the other labrid species, but it is similar to that of Labrus bergylta. During the first 16 d (after resorption of yolk-sac) brown wrasse larvae does not possess a double crescent of melanophores on top of the head, but has a few melanophores on the anal fin which is very similar to the pigmentation of Symphodus (Crenilabrus) melops larvae, although there is a difference in length between them. Larvae older than 16 d have a double crescent of melanophores on the top of the head with melanophores on the anal fin-fold identical to L. bergylta larvae, but the difference in larvae length also exists.

scholarly journals Ship waves: The relative efficiency of bow and stern

1935 ◽  
Vol 149 (868) ◽  
pp. 417-426 ◽  
Keyword(s):  
Wave Resistance ◽  
Point Of View ◽  
Experimental Results ◽  
Theoretical Point ◽  
Surrounding Water ◽  
Fluid Friction ◽  
Simple Modification ◽  
Ship Waves ◽  
The Difference ◽  
Asymmetrical Model

It seems fairly certain that one of the main causes of difference between theoretical and experimental results is the neglect of fluid friction in the calculation of ship wave, and further that the influence of fluid friction may be regarded chiefly as one which makes the rear portion of the ship less effective in generating wave than the front portion. The process may be pictured, possibly, in terms of a friction belt or boundary layer whose more important effect is equivalent to smoothing the lines of the model towards the rear. Some calculations were made from this point of view in a previous paper, the purpose then being to show how such an asymmetry, fore and aft, reduced the magnitude of interference effects between how and stern waves. We may also describe the frictional effect as a diminution in the effective relative velocity of the model and the surrounding water as we pass from how to stern. This is not very satisfactory from a theoretical point of view; but, on the other hand, it leads to a comparatively simple modification of expressions for the waves produced by the model. From a formal point of view, we may regard the modification as an empirical introduction of a reducing factor to allow for decrease in efficiency of the element of the ship's surface as we pass from how to stern. There are now available experimental results, for wave profiles as well as for wave resistance, which made it possible to attempt such a comparison. The following work is limited to a few simple cases, and the assumptions are made in as simple a form as possible for the purpose of the calculations; these deal with the wave profile and wave resistance of a model of symmetrical form, and also with the difference between motion how first and motion stern first for a simple asymmetrical model.

scholarly journals Physiological response, function of sweat glands, and hair follicle cycling in cattle in response to fescue toxicosis and hair genotype

2020 ◽  
Vol 98 (3) ◽  
Author(s):  
Joan H Eisemann ◽  
Melissa S Ashwell ◽  
Thomas L Devine ◽  
Daniel H Poole ◽  
Matt H Poore ◽  
...  
Keyword(s):  
Hair Follicle ◽  
Tall Fescue ◽  
Transepidermal Water Loss ◽  
Repeated Measure ◽  
Sweat Glands ◽  
Fescue Toxicosis ◽  
Wild Type ◽  
Physiological Variables ◽  
Hair Samples ◽  
The Difference

Abstract Fescue toxicosis is a syndrome that results when cattle consume toxic endophyte-infected tall fescue. The objective of this study was to compare the response in physiological variables, sweat gland function, hair follicle cycling, and gene expression to feeding a total mixed ration that included tall fescue haylage and tall fescue seed containing a toxic endophyte (EI) or tall fescue haylage containing a nontoxic novel endophyte (EN) in beef heifers (Angus × Senepol heifers, n = 31) with 2 different hair genotypes. Numbers in each subgroup were as follows: novel endophyte, heterozygous slick (EN-S; n = 8), novel endophyte, homozygous hairy (wild type, EN-W; n = 7), endophyte-infected, heterozygous slick (EI-S; n = 10), and endophyte-infected, homozygous hairy (wild type, EI-W; n = 6). Physiological measurements were taken weekly for 7 wk. Data were analyzed using the MIXED procedure of SAS including dietary fescue treatment (EN vs. EI) and hair genotype (S vs. W) as main effects, day as a repeated measure, and temperature–humidity index (THI) as a covariate. Skin biopsies were taken before treatment initiation and on day 37 of treatment. Average surface temperature (ST) increased as the THI increased (P &lt; 0.0001). Average ST was greater (P &lt; 0.01) for animals fed EI than for animals fed the EN fescue diet, and greater (P &lt; 0.01) for animals with the W genotype compared with animals with the S genotype. The difference between heifers with the S and W genotype was greater at greater THI (genotype × day interaction, P &lt; 0.01). Transepidermal water loss (TEWL) was greater (P &lt; 0.05) for animals with the S genotype compared with the W genotype and greater (P &lt; 0.05) for heifers with the S genotype than for heifers with the W genotype when fed EI (36.7, 38.5, 30.0, and 38.7 g/m2 per hour for EN-W, EN-S, EI-W, and EI-S, respectively). The fraction of follicles in telogen in plucked hair samples for heifers fed EI was greater for animals with the S genotype than the W genotype (fraction in telogen: 0.456, 0.565, 0.297, 0.702 for EN-W, EN-S, EI-W, and EI-S, respectively; diet × genotype interaction, P &lt; 0.05). Fraction of follicles in anagen was the opposite. EI fescue resulted in increased ST, changes in hair follicle cycling that support greater hair growth, and decreased TEWL for heifers with the W genotype compared with S genotype, suggesting greater heat stress in response to EI.

Acclimatory responses of thermal physiological performances in hatchling yellow pond turtles (Mauremys mutica)

2020 ◽  
Vol 70 (1) ◽  
pp. 55-65
Author(s):  
Hongliang Lu ◽  
Yingchao Hu ◽  
Shuran Li ◽  
Wei Dang ◽  
Yongpu Zhang
Keyword(s):  
Metabolic Rate ◽  
Resting Metabolic Rate ◽  
Temperature Acclimation ◽  
Critical Thermal Maximum ◽  
Physiological Variables ◽  
Thermal Maximum ◽  
Mauremys Mutica ◽  
Different Temperatures ◽  
The Difference ◽  
Critical Thermal Minimum

Abstract Temperature is a crucial environmental factor that can strongly impact animal physiology. Here, we acclimated hatchling of Asian yellow pond turtles (Mauremys mutica) to one of two different temperatures (25 or 30°C) for four weeks to determine temperature acclimation effects on their physiology. All four measured physiological variables (righting time, resting metabolic rate, critical thermal minimum and critical thermal maximum) were significantly affected by temperature acclimation. Turtles acclimated to 25°C righted themselves more slowly and had a lower mean metabolic rate than 30°C-acclimated turtles. Turtles acclimated to 25°C were more resistant to low temperatures, but less resistant to high temperatures than 30°C-acclimated turtles, as measured by critical thermal limits. The thermal resistance range (i.e., the difference between critical thermal minimum and maximum) did not differ between the two acclimation groups. Compared with other semi-aquatic turtles, M. mutica had relatively higher acclimation response ratios for its critical thermal minimum and critical thermal maximum. Our results indicate that acclimation to relatively moderate temperatures could also produce significant responses in the thermal physiology of turtles.

Sign in / Sign up

Export Citation Format

Share Document