Anatomy and Properties of Japanese Hardwoods I. Variation of Fibre Dimensions and Tissue Proportions and their Relation to Basic Density

IAWA Journal ◽  
1991 ◽  
Vol 12 (4) ◽  
pp. 419-424 ◽  
Author(s):  
Shinji Fujiwara ◽  
Kazuhiko Sameshima ◽  
Kenichi Kuroda ◽  
Norio Takamura
Keyword(s):  
Wall Thickness ◽  
Fibre Length ◽  
Basic Density ◽  
Cross Sectional Area ◽  
Wall Material ◽  
Sectional Area ◽  
Cross Sectional ◽  
Wall Area ◽  
Fibre Wall ◽  
Area Percentage

Variations of tissue proportions and fibre dimensions (fibre length, fibre cross sectional area, fibre wall thickness, fibre wall area, percentage of fibre wall area) of 50 Japanese hardwoods are compared. The fibre cross sectional area showed large variations as compared to fibre length. There is no significant correlation between fibre cross sectional area and fibre wall thickness.The multiple regression analysis showed that fibre wall thickness, percentage of fibre wall material and ray volume are the parameters most closely correlated with basic density.

A fractal analysis of the radial distribution of bronchial capillaries around large airways

2005 ◽  
Vol 98 (3) ◽  
pp. 850-855 ◽  
Author(s):  
Joseph C. Anderson ◽  
Albert L. Babb ◽  
Michael P. Hlastala
Keyword(s):  
Fractal Dimension ◽  
Radial Distribution ◽  
Fractal Analysis ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Airway Wall ◽  
Cross Sectional ◽  
Wall Area ◽  
Bronchial Circulation ◽  
Epithelial Basement Membrane

We analyzed published measurements of the bronchial circulation and airway wall (Anderson JC, Bernard SL, Luchtel DL, Babb AL, and Hlastala MP. Respir Physiol Neurobiol 132: 329–339, 2002) and determined that the radial distribution of bronchial capillary cross-sectional area was fractal. We limited our analysis to bronchial capillaries, diameter ≤10 μm, that resided between the epithelial basement membrane and adventitia-alveolar boundary, the airway wall tissue. Thirteen different radial distributions of capillary-to-tissue area were constructed simply by changing the number of annuli (i.e., the annular size) used to form each distribution. For the 13 distributions created, these annuli ranged in size from to of the size of the airway wall area. Radial distributions were excluded from the fractal analysis if the sectioning procedure resulted in an annulus with a radial thickness less than the diameter of a capillary. To determine the fractal dimension for a given airway, the coefficient of variation (CV) for each distribution was calculated, and ln(CV) was plotted against the logarithm of the relative piece area. For airways with diameter >2.4 mm, this relationship was linear, which indicated the radial distribution of bronchial capillary cross-sectional area was fractal with an average fractal dimension of 1.27. The radial distribution of bronchial capillary cross-sectional area was not fractal around airways with diameter <1.5 mm. We speculated on how the fractal nature of this circulation impacts the distribution of bronchial blood flow and the efficiency of mass transport during health and disease. A fractal analysis can be used as a tool to quantify and summarize investigations of the bronchial circulation.

Conservation of bronchiolar wall area during constriction and dilation of human airways

1997 ◽  
Vol 82 (3) ◽  
pp. 954-958 ◽  
Author(s):  
R. W. Mitchell ◽  
E. Rühlmann ◽  
H. Magnussen ◽  
N. M. Muñoz ◽  
A. R. Leff ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Contraction ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Wall Area ◽  
Total Cross Sectional Area ◽  
Human Airways ◽  
Contraction And Relaxation

Mitchell, R. W., E. Rühlmann, H. Magnussen, N. M. Muñoz, A. R. Leff, and K. F. Rabe. Conservation of bronchiolar wall area during constriction and dilation of human airways. J. Appl. Physiol. 82(3): 954–958, 1997.—We assessed the effect of smooth muscle contraction and relaxation on airway lumen subtended by the internal perimeter ( A i) and total cross-sectional area ( A o) of human bronchial explants in the absence of the potential lung tethering forces of alveolar tissue to test the hypothesis that bronchoconstriction results in a comparable change of A iand A o. Luminal area (i.e., A i) and A owere measured by using computerized videomicrometry, and bronchial wall area was calculated accordingly. Images on videotape were captured; areas were outlined, and data were expressed as internal pixel number by using imaging software. Bronchial rings were dissected in 1.0- to 1.5-mm sections from macroscopically unaffected areas of lungs from patients undergoing resection for carcinoma, placed in microplate wells containing buffered saline, and allowed to equilibrate for 1 h. Baseline, A o[5.21 ± 0.354 (SE) mm2], and A i(0.604 ± 0.057 mm2) were measured before contraction of the airway smooth muscle (ASM) with carbachol. Mean A inarrowed by 0.257 ± 0.052 mm2in response to 10 μM carbachol ( P = 0.001 vs. baseline). Similarly, A onarrowed by 0.272 ± 0.110 mm2in response to carbachol ( P = 0.038 vs. baseline; P = 0.849 vs. change in A i). Similar parallel changes in cross-sectional area for A iand A owere observed for relaxation of ASM from inherent tone of other bronchial rings in response to 10 μM isoproterenol. We demonstrate a unique characteristic of human ASM; i.e., both luminal and total cross-sectional area of human airways change similarly on contraction and relaxation in vitro, resulting in a conservation of bronchiolar wall area with bronchoconstriction and dilation.

Methods of analysis and the influence of fleece characters on unit area wool production of Romney lambs

1960 ◽  
Vol 11 (5) ◽  
pp. 851 ◽  
Author(s):  
AE Henderson ◽  
BI Hayman
Keyword(s):  
Unit Area ◽  
Fibre Length ◽  
Fibre Volume ◽  
Cross Sectional Area ◽  
The Body ◽  
Skin Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Wool Production ◽  
Fibre Number

Investigation has been made of the influence of fibre number per unit area (N), cross-sectional area of fibre (A), and fibre length (L), on wool production per unit area of skin (W). The influence of the compound characters fibre volume (V) and proportion of skin area occupied by fibre (0) has also been considered. Methods are given whereby the significance of the variation associated with any one of these interacting components can be assessed. Data from four groups of lambs were analysed, each group having been subjected to a different nutritional regime. Slightly more than three-quarters of the variation induced in W by these treatments was due to variation in L, with N and A having negligible effects. No evidence was found that the relative influence of the components changed with change in level of production. Differences in W between lambs on the same nutritional level were influenced almost equally by variation in N and L, with A again having a negligible effect. Of the variation in W between positions on lambs, approximately 50 per cent. was accounted for by variation in N, 40 per cent. by variation in A, and 10 per cent. by variation in L. Variation of the compound character O accounted for nearly 90 per cent. of the variation in W over the body.

scholarly journals Evaluation of Fecal Calprotectin, D-Lactic Acid and Bedside Gastrointestinal Ultrasound Image Data for the Prediction of Acute Gastrointestinal Injury in Sepsis Patients

2021 ◽  
Vol 3 ◽  
Author(s):  
Junlu Li ◽  
Yanbo Ren ◽  
Chang Gao ◽  
Kaili Zhang ◽  
Fuwen Zheng ◽  
...  
Keyword(s):  
Small Intestine ◽  
Lactic Acid ◽  
Wall Thickness ◽  
Diameter Ratio ◽  
Cross Sectional Area ◽  
Gastric Antrum ◽  
Control Group ◽  
Outer Diameter ◽  
Sectional Area ◽  
Cross Sectional

Objective: To investigate the early warning and prognostic evaluation of fecal calprotectin (FC), D-lactic acid, and bedside gastrointestinal ultrasound (B-GIUS) data for acute gastrointestinal injury (AGI) in sepsis patients.Main Method: Sepsis patients were grouped based on the presence or absence of AGI into AGI and non-AGI groups. Healthy volunteers of the same period were selected as the control group. FC, B-GIUS data, D-lactic acid, etc. were collected on the 1st, 3rd and 7th days of admission. Twenty-eight-day mortality was recorded.Main Results: FC, D-lactic acid levels, gastric antrum cross-sectional area, and small intestine wall thickness were significantly increased in group A and B (P &lt; 0.05); furthermore, inner-to-outer diameter ratio and cross-sectional area of small intestine were lower than those in the control group (P &lt; 0.05). FC, D-lactic acid, gastric antrum cross-sectional area and small intestine wall thickness in AGI group were higher than those in non-AGI group (P &lt; 0.05). Inner-to-outer diameter ratio and cross-sectional area of small intestine in AGI group were smaller than those in non-AGI group (P &lt; 0.05). There was no difference in the thickness, inner-to-outer diameter ratio nor the cross-sectional area ratio of colon between AGI and non-AGI groups (P &gt; 0.05). AUC for D-lactic acid was 0.881, which was higher than FC's (0.74). When the D-lactic acid cutoff value was 22.16 μmol/L, the sensitivity was 77.9% and the specificity was 92% for the prediction of AGI in sepsis. AUC for the cross-sectional area of the gastrointestinal antrum was 0.657, which was higher than the small intestine thickness's (0.629). When the gastric antrum cross-sectional area was larger than 4.20 cm2, the sensitivity was 64% and the specificity was 65.3%.Conclusion: D-Lactic acid and FC were early diagnostic indicators for sepsis with AGI, and D-lactic acid was the superior indicator. The gastric antrum cross-sectional area and the small intestine wall thickness had an early warning effect, and the prediction of the gastric antrum cross-sectional area was superior to that of the latter. Because it is non-invasive and convenient, B-GIUS can help in the diagnosis of sepsis with AGI.

Wool fibre tenacity in Romney sheep genetically different in staple tenacity

1996 ◽  
Vol 47 (8) ◽  
pp. 1203 ◽  
Author(s):  
DR Scobie ◽  
RJ Walls ◽  
LJ Markham ◽  
JL Woods ◽  
AR Bray
Keyword(s):  
Cross Section ◽  
Fibre Length ◽  
Cross Sectional Area ◽  
Peak Force ◽  
Wool Fibre ◽  
Sectional Area ◽  
Cross Sectional ◽  
Wool Sample ◽  
Image Analyser ◽  
The Difference

Wool from lines of Romney sheep selected for improved or reduced staple tenacity was examined to determine if the difference in staple tenacity was explained by a difference in fibre tenacity. A random sample of ewe hogget wools (n = 32) was chosen from each of the 2 selection lines. Fibre tenacity was measured by breaking 10 fibres from each wool sample using an Instron to measure peak force, and then a fluorescence microscope attached to an image analyser to measure cross-sectional area of the fracture surface. Staple tenacity was measured on 5 staples per sample, by placing each staple in a Staplebreaker set to 40 mm between clamps, and the peak force to break the staple was recorded. Prior to clamping, each staple was adjusted so that the thinnest point measured 1.5 mm2 in cross-section and this point was positioned 20 mm from each clamp. Although the difference in staple tenacity between these 2 groups was highly significant (P = 0.002)) there was no difference in the tenacity of individual fibres (P = 0.903). Staple tenacity was not significantly correlated with fibre tenacity (r = 0.090). Similarly, there was no significant correlation between work to break the staple and either work (r = 0.118) or peak force (r = 0.195) to break the fibre. It is proposed that other components of staple tenacity, such as the profile of cross-sectional area along the fibre and the variability of crimped fibre length within the staple, may be more important determinants of staple tenacity in these selection lines.

Correlation of Physiological Cross-Sectional Areas of Muscle and Tendon

1991 ◽  
Vol 16 (1) ◽  
pp. 66-67 ◽  
Author(s):  
K.-N. AN ◽  
R. L. LINSCHEID ◽  
P. W. BRAND
Keyword(s):  
Tendon Transfer ◽  
Muscle Mechanics ◽  
Fibre Length ◽  
Cross Sectional Area ◽  
Maximum Strength ◽  
Sectional Area ◽  
Cross Sectional ◽  
Sports Science ◽  
Transfer Procedures

Muscle physiological cross-sectional area, as defined and measured by dividing the volume of the muscle by its fibre length, is proportional to the maximum strength of the muscle. It is one of the important parameters when considering muscle mechanics in sports science and, clinically in tendon transfer procedures. This study reports that tendon cross-sectional area correlated well with the physiological cross-sectional area of associated muscles.

scholarly journals 3D geometry of femoral reaming for bone graft harvesting

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dominic Gehweiler ◽  
Nina Schmitz ◽  
Boyko Gueorguiev ◽  
Ivan Zderic ◽  
Leonard Grünwald ◽  
...  
Keyword(s):  
Ct Scan ◽  
Bone Graft ◽  
Wall Thickness ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Relative Decrease ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

AbstractThe reamer-irrigator-aspirator (RIA) technique allows to collect large bone graft amounts without the drawbacks of iliac crest harvesting. Nevertheless, clinical cases with occurrence of femur fractures have been reported. Therefore, this study aimed to systematically investigate the three-dimensional geometry of the reamed bone as a function of the reaming diameter and its influence on the associated potential fracture pattern. Forty-five intact fresh-frozen human cadaveric femora underwent computed tomography (CT). They were randomized to three groups (n = 15) for reaming at a diameter of either 1.5 mm (Group 1), 2.5 mm (Group 2) or 4.0 mm (Group 3) larger than their isthmus using RIA. Reaming was followed by a second CT scan, biomechanical testing until failure and a third CT scan. All CT scans of each femur were aligned via rigid registration, and fracture lines were visualized. Subsequently, a decrease in wall thickness, cross-sectional area, and harvested bone volume have been evaluated. The total volume of the bone graft was significantly higher for Group 3 (7.8 ± 2.9 ml) compared to Group 1 (2.9 ± 1.1 ml) and Group 2 (3.0 ± 1.1 ml). The maximal relative decrease of the wall thickness was located medially (72.7%) in the third (61.4%), fourth (18.2%) and second (9.1%) eighth for all groups. As the diameter of the reaming increased, an overlap of the fracture line with the maximal relative decrease in wall thickness and a maximal average relative decrease of the cross-sectional area became more frequent. This suggests that a reaming-associated fracture is most likely to occur in this region.

P56 CENTRAL PULSE PRESSURE IS ASSOCIATED WITH RETINAL ARTERIOLAR WALL THICKNESS AND WALL CROSS SECTIONAL AREA AS EVALUATED BY ADAPTIVE OPTICS

2018 ◽  
Vol 24 (C) ◽  
pp. 94
Author(s):  
Antonio Gallo ◽  
Thomas Dietenbeck ◽  
Nadjia Kachenoura ◽  
Valérie Carreau ◽  
Michel Paques ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Wall Thickness ◽  
Pulse Pressure ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Arteriolar Wall ◽  
Central Pulse Pressure ◽  
Retinal Arteriolar

A study of wool growth: Part II. Mean fibre thickness, density of fibre population, the area of skin covered by fibre, and the mean fibre length

1948 ◽  
Vol 38 (3) ◽  
pp. 303-313 ◽  
Author(s):  
N. Galpin
Keyword(s):  
Unit Area ◽  
Fibre Length ◽  
Expansion Ratio ◽  
Cross Sectional Area ◽  
Skin Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
The Mean ◽  
Length And Area ◽  
Growing Conditions

SUMMARYBy measurement of single fibres from tattooed squares the variation in hip region mean cross-sectional area, mean fibre length and area of skin covered by fibre substance in a small flock of Romney sheep has been studied for a few years—see Part I.We find that under good growing conditions the area of skin covered by fibre is a constant percentage of the skin area for all sheep in all years. The number of fibres per unit area varies from sheep to sheep, and the mean cross-sectional area is inversely proportional to the number of fibres per unit area. The mean length/day is a constant for all sheep. When conditions are unfavourable the percentage of the skin area covered by fibre on a particular sheep falls below the good growing conditions percentage by an amount that is smaller the bigger the skin expansion ratio, but is greater the worse the season.

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