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.

scholarly journals Comparison of Muscle Cross-sectional Area and Lumbar Muscle Strength According to Degenerative Spinal Diseases

2020 ◽  
Vol 22 (2) ◽  
pp. 1-10
Author(s):  
Ji-Hoon Cho ◽  
Ki-Hyuk Lee ◽  
Seung-Taek Lim ◽  
Buong-O Chun
Keyword(s):  
Muscle Strength ◽  
Cross Sectional Area ◽  
Spinal Diseases ◽  
Sectional Area ◽  
Multifidus Muscle ◽  
Cross Sectional ◽  
Total Group ◽  
Male Group ◽  
The Difference ◽  
Lumbar Extension

OBJECTIVES The purpose of this study was to investigate the difference in the cross - sectional area (CSA) of multifidus and Iliopsoas muscles and the lumbar extension muscle strength according to degenerative spinal diseases (LHI; lumbar herniation of intervertebral disc group, SS; spinal stenosis group, S; spondylolisthesis group).METHODS The CSA of multifidus and Iliopsoas muscles size were measured by PACS(Picture Achiving and Communication System) using MRI at the L4/5 level and lumbar extension muscle strength (72˚, 60˚, 48˚, 36˚, 24˚, 12˚, 0˚) was measured using lumbar extension machine(MedX) in 97 patients of degenerative spinal diseases(male: 57, female: 40). The collected data were analyzed by one-way ANOVA using the SPSS program.RESULTS The results of this study showed that the CSA of total and right multifidus muscle in the LHI was significantly higher than that of the S (p <.05; p <.05) in the male group. The difference between the left and right CSA of multifidus in the LHI group was significantly higher than that of the SS (p <.05) in the male group (p <.05) and total group (p <.05). The CSA of iliopsoas muscle in the S was significantly higher than that of the LHI in the male and total group (p <.05; p <.05). In case of lumbar extension muscle strength, the S showed significantly higher muscle strength at 36 and 48 degrees than that of the SS in the male group. In the total group, LHI showed significantly higher muscle strength at 60 degrees of lumbar extension muscle strength than that of the S.CONCLUSION Multifidus muscle appears to be a key factor in prevention and treatment intervention in low back pain patients. In particular, in the case of S group, exercise therapy for strengthening the multifidus muscle is need for the rehabilitation.

Maintenance of myonuclear domain size in rat soleus after overload and growth hormone/IGF-I treatment

1998 ◽  
Vol 84 (4) ◽  
pp. 1407-1412 ◽  
Author(s):  
G. E. McCall ◽  
D. L. Allen ◽  
J. K. Linderman ◽  
R. E. Grindeland ◽  
R. R. Roy ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Domain Size ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Muscle Weight ◽  
Cross Sectional ◽  
Igf I ◽  
Myonuclear Domain ◽  
The Difference ◽  
Saline Vehicle

The purpose of this study was to determine the effects of functional overload (FO) combined with growth hormone/insulin-like growth factor I (GH/IGF-I) administration on myonuclear number and domain size in rat soleus muscle fibers. Adult female rats underwent bilateral ablation of the plantaris and gastrocnemius muscles and, after 7 days of recovery, were injected three times daily for 14 days with GH/IGF-I (1 mg/kg each; FO + GH/IGF-I group) or saline vehicle (FO group). Intact rats receiving saline vehicle served as controls (Con group). Muscle wet weight was 32% greater in the FO than in the Con group: 162 ± 8 vs. 123 ± 16 mg. Muscle weight in the FO + GH/IGF-I group (196 ± 14 mg) was 59 and 21% larger than in the Con and FO groups, respectively. Mean soleus fiber cross-sectional area of the FO + GH/IGF-I group (2,826 ± 445 μm2) was increased compared with the Con (2,044 ± 108 μm2) and FO (2,267 ± 301 μm2) groups. The difference in fiber size between the FO and Con groups was not significant. Mean myonuclear number increased in FO (187 ± 15 myonuclei/mm) and FO + GH/IGF-I (217 ± 23 myonuclei/mm) rats compared with Con (155 ± 12 myonuclei/mm) rats, although the difference between FO and FO + GH/IGF-I animals was not significant. The mean cytoplasmic volume per myonucleus (myonuclear domain) was similar across groups. These results demonstrate that the larger mean muscle weight and fiber cross-sectional area occurred when FO was combined with GH/IGF-I administration and that myonuclear number increased concomitantly with fiber volume. Thus there appears to be some mechanism(s) that maintains the myonuclear domain when a fiber hypertrophies.

scholarly journals A Comparison of the Arithmetic and Geometric Means in Estimating Stump Diameter, Basal Area, and Volume in Appalachian Hardwoods

2007 ◽  
Vol 24 (1) ◽  
pp. 71-73 ◽  
Author(s):  
Harry V. Wiant ◽  
John R. Brooks
Keyword(s):  
Geometric Mean ◽  
Basal Area ◽  
Cross Sectional Area ◽  
Practical Significance ◽  
Sectional Area ◽  
Cross Sectional ◽  
Geometric Means ◽  
The Difference ◽  
Appalachian Hardwoods ◽  
Stump Diameter

Abstract The difference between the use of the arithmetic and geometric means for estimation of average stump diameter, stump cross-sectional area and estimated tree volume was investigated using measurements from 739 stumps from an Appalachian hardwood stand located in central West Virginia. Although average stump diameter, cross-sectional area, and tree volumes were statistically different between estimates based on the arithmetic and geometric mean diameter, these differences were of little practical significance. The difference in average stem diameter, cross-sectional area, tree cubic volume, and board foot volume were 0.05 in, 0.01 ft2, 0.45 ft3, and 2.41 bd ft, respectively.

Modelling the Acoustical and Airflow Performance of Simple Lined Ventilation Apertures

2005 ◽  
Vol 12 (4) ◽  
pp. 277-292 ◽  
Author(s):  
D J Oldham ◽  
Jian Kang ◽  
M W Brocklesby
Keyword(s):  
Aspect Ratio ◽  
Cross Section ◽  
High Aspect Ratio ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Ventilation Performance ◽  
Acoustic Treatment

The pressure differences that can be used to drive a natural ventilation system are very small and thus large apertures are required to allow sufficient air to enter and leave a building to ensure good air quality or thermal comfort. Large apertures are potential acoustic weak points on a façade and may require some form of acoustic treatment such as absorbent linings, in which case the ventilator is similar to a short section of lined duct. In ducts, the performance of absorbent linings increases with the length of lining and the ratio of the length of lined perimeter to the cross sectional area of the duct. Thus, for a duct of a given cross sectional area, a lining is more effective for a duct with a high aspect ratio than for a duct with a square cross section. However, the high aspect ratio cross section will result in greater flow resistance and impede the airflow performance. In this paper numerical methods are employed to investigate the effect of different configurations of a lined aperture on the acoustical and ventilation performance of the aperture in order to establish the optimum configurations.

scholarly journals Numerical simulation of cutting layer in internal corners milling

Mechanik ◽  
2019 ◽  
Vol 92 (7) ◽  
pp. 412-414
Author(s):  
Jan Burek ◽  
Rafał Flejszar ◽  
Barbara Jamuła
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Cross Section ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Cross Section Area ◽  
Section Area ◽  
The Cross ◽  
The Stability

The analytical and numerical model of the cross-section of the machined layer in the process of milling of concave rounding is presented. Simulation tests were carried out to determine the cross-sectional area of the cutting layer. A strategy has been developed that allows to increase the stability of the cross-section area of the cutting layer when the mill enters the inner corner area.

Normalization of force generated by canine airway smooth muscles

1991 ◽  
Vol 260 (6) ◽  
pp. L522-L529 ◽  
Author(s):  
H. Jiang ◽  
A. J. Halayko ◽  
K. Rao ◽  
P. Cunningham ◽  
N. L. Stephens
Keyword(s):  
Smooth Muscle ◽  
Cross Section ◽  
Cross Sections ◽  
Smooth Muscles ◽  
Muscle Cells ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Muscle Stress ◽  
Total Tissue

A variety of normalizations have been employed to compare maximal isometric force (Po) produced by smooth muscles at different locations and stages of maturation. Because these procedures have not always been based on rigorous principles, confusion has resulted. To obtain a less ambiguous index of force production, we measured in vitro Po from mongrel canine tracheal (TSM) and bronchial (BSM) smooth muscle with an electromagnetic lever and normalized it to force per unit cross-sectional area of whole tissue (tissue stress), to force per unit cross-sectional area of muscle in the cross section of total tissue (muscle stress), and to force per fractional unit of myosin in the tissue cross section (myosin stress). Proportion of myosin in cross-sectional area of tissue was deduced from data obtained by sodium dodecyl sulfate gel electrophoresis of crude muscle extracts. For TSM, tissue stress was 1.499 X 10(5) N/m2 +/- 0.1 (SE), whereas it was only 0.351 X 10(5) N/m2 +/- 0.05 (SE) for BSM, representing a 4.27-fold difference (P less than 0.01). There was a 1.60-fold difference (P less than 0.05) in muscle stress, which was correlated to the morphometric finding that 79 +/- 1.4% (SE) of the tracheal strip cross section was muscle, whereas only 30 +/- 1.0% (SE) of bronchial tissue was occupied by muscle. Average myosin content was the same in smooth muscle cells of TSM and BSM, indicating that total amount of myosin in tissue cross sections was essentially a function of proportional area of muscle cells in total tissue cross sections.(ABSTRACT TRUNCATED AT 250 WORDS)

Wool fibre tenacity and its relationship to staple strength

1992 ◽  
Vol 43 (8) ◽  
pp. 1759 ◽  
Author(s):  
RG Gourdie ◽  
DFG Orwin ◽  
S Ranford ◽  
DA Ross
Keyword(s):  
Fibre Diameter ◽  
Breaking Load ◽  
Cross Sectional Area ◽  
Wool Fibre ◽  
Material Strength ◽  
Sectional Area ◽  
Cross Sectional ◽  
Significant Relationships ◽  
Staple Strength ◽  
Axial Splitting

Wool fibre tenacity and its relationship to staple strength was studied in a pen-feeding trial of 40 New Zealand Romney ewes. A method for estimating fibre tenacity is described based on normalizing fibre breaking load by cross-sectional area measured on fibre fracture-surfaces. The validity of this protocol was demonstrated by showing that (i) fibre diameter measured at the point of rupture was not significantly (P > 0.05) changed by breaking, and (ii) that the tenacity estimate was not significantly (P > 0.05) correlated with cross-sectional area variation along fibres, and (iii) showed lower fibre-to-fibre variation than other accepted measures of intrinsic material strength. The majority (83.5%) of the 1200 fibres broken in this study cleaved in smooth-planed fractures normal to the long axis of the fibre, the remaining fibres demonstrated axial-splitting following rupture. Tenacity did not differ significantly between the two break-types (P > 0.05). Tenacity demonstrated small negative correlations (P < 0.05) with fibre cross-sectional area and ellipticity. No change in tenacity (P > 0.05) occurred within fine, slow-growing 'wool-break' regions and tenacity did not vary significantly (P < 0.05) between body sites on sheep. Tenacity showed no significant variation (P > 0.05) with differential winter feeding, but significant variations (P < 0.01) of wool tenacity occurred between sheep. The sheepto-sheep differences in tenacity showed significant relationships with two indices of staple strength, work (P < 0.01) and peak-force (P < 0.01). Variability in fibre tenacity between sheep and its relationship to staple strength may provide some explanation of the origin of 'tender' and 'sound' wools.

Corrosion-Induced Concrete Cracking, Steel-Concrete Bond Loss, and Mechanical Degradation of Steel Bars

2014 ◽  
Vol 919-921 ◽  
pp. 1760-1770 ◽  
Author(s):  
Fu Jian Tang ◽  
Gen Da Chen ◽  
Wei Jian Yi
Keyword(s):  
Cross Section ◽  
Crack Width ◽  
Surface Profile ◽  
Concrete Surface ◽  
Cross Sectional Area ◽  
Mechanical Degradation ◽  
Sectional Area ◽  
Cross Sectional ◽  
Steel Bars ◽  
The Cross

This study experimentally investigated corrosion-induced deterioration in reinforced concrete (RC) structures: concrete cover cracking, steel-concrete bond loss, and mechanical degradation of corroded steel bars. Pullout and RC beam specimens were prepared, subjected to accelerated corrosion in a wet sand bath, and tested under loading. A 3D laser scan was employed to measure the surface profile of corroded steel bars and determine the corrosion effect on the distribution of residual cross section area. The crack width on the concrete surface was sampled randomly and analyzed statistically. Corrosion reduced the bond strength between steel bars and concrete, particularly in the form of corrosion-induced number and width of cracks. Both the yield and ultimate strengths depended upon the critical cross sectional area of steel bars, whereas the elongation changed with the cross section distribution over the length of the steel bars. Corrosion also changed the distribution of the cross sectional area of steel bars. The crack width on the concrete surface can be well represented by a normal distribution regardless of corrosion levels.

Dynamic Detection and Analysis of Raw Silk’s Flatness

2011 ◽  
Vol 175-176 ◽  
pp. 385-388
Author(s):  
Xin Zhang ◽  
Yi Quan Xu ◽  
Kai Meng ◽  
Qing Guan Chen
Keyword(s):  
Cross Section ◽  
Axial Length ◽  
Minor Axis ◽  
Cross Sectional Area ◽  
Elliptical Cross Section ◽  
Sectional Area ◽  
Cross Sectional ◽  
Elliptical Cross ◽  
Photoelectric Sensor ◽  
Dynamic Detection

The shape of most raw silk’s cross-section can be regarded as ellipse approximately. Axial length of the raw silk’s cross-section was detected and recorded dynamically by photoelectric sensor combined with the software of LabVIEW. Two photoelectric sensors were located orthogonally to measure axial lengths of the ellipse. The major and minor values can be considered as the major and minor axis values of the raw silk’s elliptical cross-section respectively. Thereby, the flatness and the area of raw silk’s cross-section can be calculated according to the values of major and minor axes. In addition, the raw silk’s evenness was characterized based on the variation of the cross-sectional area.

Analysis of the Cross-Sectional Area of the Adductor Longus Tendon

2007 ◽  
Vol 35 (6) ◽  
pp. 996-999 ◽  
Author(s):  
Eric J. Strauss ◽  
Kirk Campbell ◽  
Joseph A. Bosco
Keyword(s):  
Cross Section ◽  
Muscle Fibers ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Sectional Anatomy ◽  
Longus Muscle ◽  
The Cross ◽  
Adductor Longus ◽  
Muscle Origin

Background Strain injury to the adductor longus muscle is a common cause of groin pain in athletes and generally occurs in the proximal portion of the muscle, near its origin from the anterior aspect of the pubis. The composition and cross-sectional anatomy of this muscle's origin has not been previously described. Hypothesis We hypothesize that the adductor longus muscle origin is composed mainly of muscle fibers and that the tendon composes only a small part of the cross section at the origin of the muscle. Study Design Descriptive laboratory study. Methods We harvested 42 adductor longus muscles from 28 cadavers and measured the cross-sectional dimensions of the tendon with microcalipers. Next, we determined the relative contributions of the tendon and muscle fibers to the cross-sectional anatomy of the muscle using optical scanning. These 2 sets of measurements were obtained at 3 locations: at the muscle origin and 1.0 and 2.0 cm distal to the origin. Results The average length and width of the tendon was 11.6 and 3.7 mm, respectively, at the origin. The average cross-sectional areas of the tendon were 49.3, 27.9, and 25.7 mm2 at points 0.0, 1.0, and 2.0 cm from its origin, respectively. The origin of the adductor longus muscle was composed of 37.9% tendon and 62.1% muscle tissue. At 1.0 cm from the origin, the percentage of tendon decreased to 34%. At 2.0 cm from the origin, the tendon composed 26.7% of the cross section. Conclusion The cross-sectional area of the tendon of the adductor longus muscle is relatively small. The muscle origin is composed predominantly of direct attachment of muscle fibers. Clinical Relevance Knowledge of the cross-sectional anatomy of the adductor longus muscle at its origin may help clinicians better understand the complex nature of injuries in this area.

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