scholarly journals Ultrasound and Microwave Aided Natural Dyeing of Nettle Biofibre (Urtica dioica L.) with Madder (Rubia tinctorum L.)

2017 ◽  
Vol 25 (0) ◽  
pp. 111-120 ◽  
Author(s):  
Arzu Yavas ◽  
Ozan Avinc ◽  
Görkem Gedik
Keyword(s):  
Urtica Dioica ◽  
Silk Suture ◽  
Bending Rigidity ◽  
Structural Variations ◽  
Bending Properties ◽  
Suture Materials ◽  
Rubia Tinctorum ◽  
Pass Through ◽  
Mechanical Performances ◽  
Sheath Structure

The success of suture yarn depends upon its tensile and bending properties. As sutures pass through the tissue, it should possess enough strength to hold the tissue together and should be flexible so as to be knotted. The aim of the present work was to improve the strength of silk suture without affecting its bending properties. Silk sutures were fabricated using a circular braiding machine. Structural variations were made by varying the diameter and by producing core sheath suture yarn. The resulting suture yarn is coated with chitosan – a biopolymer. The mechanical performances of suture materials coated with and without chitosan were studied and compared with commercial suture. It was observed that the suture with a core-sheath structure performed well during tensile and knot testing. The coarser yarns exhibited higher bending rigidity and lower knot strength than the finer suture yarns.

Isotope Effect Studies on Elimination Reactions. XI. The Nature of the Transition State for the E2 Reaction of 2-Phenylethyldimethylanilinium Salts Containing Substituents in the Aniline Ring with Sodium Ethoxide in Ethanol

1975 ◽  
Vol 53 (23) ◽  
pp. 3513-3525 ◽  
Author(s):  
Peter Schmid ◽  
Arthur Newcombe Bourns
Keyword(s):  
Transition State ◽  
Isotope Effect ◽  
Structural Changes ◽  
Isotope Effects ◽  
Sodium Ethoxide ◽  
Nitrogen Isotope ◽  
Structural Variations ◽  
Hydrogen Deuterium ◽  
Elimination Reactions ◽  
Pass Through

Kinetic isotope effects have been determined for the E2 reactions of a series of 2-phenylethyldimethylanilinium salts containing substituents in the aniline ring with sodium ethoxide in ethanol at 40 °C. The nitrogen isotope effect, (k14/k15−1)100, is not very sensitive to substituent changes but appears to increase slightly with increasing electron-withdrawing ability of the substituents, i.e., 1.19 ± 0.07, 1.13 ± 0.06, 1.12 ± 0.08, 1.30 ± 0.07, and 1.32 ± 0.06 for p-OCH3, p-CH3, p-H, p-Cl, and, m-CF3, respectively. The hydrogen–deuterium isotope effects pass through a minimum in the region of the unsubstituted compound and increase both with increasing electron-donating as well as with electron-withdrawing power of the substituents, i.e. kH/kD = 4.70 ± 0.06, 4.61 ± 0.04, 4.51 ± 0.04, 4.53 ± 0.09, 5.00 ± 0.07, and 5.39 ± 0.07 for p-OCH3, p-CH3, p-H, p-Cl, m-CF3, and p-CF3, respectively. The results are discussed in terms of recent theoretical treatments of the effect of structural variations in the reactants on the nature of the transition state of E2 elimination reactions. The conclusion is reached that the transition states in the present reaction series can be characterized as 'central with slight carbanion character' and that the effect of a change in the ability of the leaving group on the structure of the transition state manifests itself mainly in the direction perpendicular to the reaction coordinate. A simple novel hypothesis is formulated which emphasizes the importance of the location of the transition state in a More O'Ferrall-type potential energy diagram in determining its sensitivity to structural changes in the reactants.

scholarly journals Fibroin allergy. IgE mediated hypersensitivity to silk suture materials.

1999 ◽  
Vol 66 (1) ◽  
pp. 41-44 ◽  
Author(s):  
Sadayuki Kurosaki ◽  
Hirokuni Otsuka ◽  
Mayumi Kunitomo ◽  
Mamoru Koyama ◽  
Ruby Pawankar ◽  
...  
Keyword(s):  
Silk Suture ◽  
Suture Materials ◽  
Ige Mediated

Grey Clustering Analysis of the Bending Creasing and Draping Properties of Bamboo Pulp/Cotton Interwoven Fabric

2012 ◽  
Vol 538-541 ◽  
pp. 1737-1741 ◽  
Author(s):  
Shun Bin Ma
Keyword(s):  
Elastic Modulus ◽  
Clustering Analysis ◽  
Elastic Recovery ◽  
Bending Rigidity ◽  
Bending Properties ◽  
Bamboo Pulp ◽  
Grey Clustering ◽  
Good Standard

The properties of fifteen bamboo/cotton interwoven fabrics with different specifications were tested, such as static drape coefficient, dynamic drape coefficient, total bending rigidity, elastic modulus of bending, the angle of fast-elastic recovery, the angle of delayed-elastic recovery,etc. then the author took these properties index as clustering index, fifteen bamboo/cotton interwoven fabrics as clustering object, using the grey clustering analysis to evaluate the bending，creasing and draping properties synthetically. The results show that: The first grey type including 1#、2#、3#、4#、7#、8#、10#、11#, achieved optimal standard；The second grey type including 5#、6#、9#，achieved good standard；The Superscript text third grey type including 12#、13#、14#、15#，their bending properties、creasing properties and draping properties were poor.

Using KES-F System for Determining the Bending Properties of Paper Towels

2016 ◽  
Vol 848 ◽  
pp. 170-173
Author(s):  
Chi Wai Kan ◽  
Maggie Hoi Man Leung ◽  
Rattanaphol Mongkholrattanasit
Keyword(s):  
Evaluation System ◽  
Bending Moment ◽  
Experimental Results ◽  
Local Market ◽  
Bending Rigidity ◽  
Bending Properties ◽  
Paper Towels ◽  
F System

12 commercially available paper towels were collected from the local market and studied in this paper. Kawabata Evaluation System for Fabric (KES-F) was used for evaluating their bending properties. Two bending properties namely: (i) bending rigidity (B) and (ii) bending moment (2HB) were evaluated. Experimental results indciated that the bending properties varied within the products. B was used as the key property for discussing the bending properties of paper towels. When the correlations of different bending properties were investigated, it was found that no significant was found between B and 2HB. However, there was significant statistically relationship between weight and B but no relationship between thickness and B. With the use of the results, the product developer could improve the bending properties of the paper towels.

scholarly journals Keratometric astigmatism evaluation after trabeculectomy

2013 ◽  
Vol 5 (2) ◽  
pp. 215-219 ◽  
Author(s):  
Rashmi Kumari ◽  
BC Saha ◽  
LR Puri
Keyword(s):  
Mathematical Expression ◽  
Silk Suture ◽  
Interventional Study ◽  
Suture Materials ◽  
Surgically Induced Astigmatism ◽  
Vector Decomposition ◽  
Induced Astigmatism ◽  
The Mean ◽  
Surgically Induced ◽  
Time Point

Introduction: Post-operative astigmatism is one of the most important causes for diminution of vision after trabeculectomy. Objective: To evaluate the induced corneal astigmatism following trabeculectomy with the use of 8-0 silk suture. Materials and methods: A prospective interventional study was done including 100 consecutive eyes of 84 patients who underwent trabeculectomy with the use of 8-0 silk suture. The postoperative induced astigmatism on the 1st post-operative day, 3rd week and after 6 months was determined. Statistics: Vector analysis was performed on the data using a computerized method for calculating the surgically induced astigmatism (SIA) for each eye at every time point postoperatively. In order to analyze group changes, we also performed vector decomposition which gave us a mathematical expression of the changes in astigmatism “with the rule” (WTR) or “against the rule” (ATR). Results: The mean age of all the patients was 53.31 11.39 years. The mean 1st post-operative surgically induced astigmatism (SIA) was 2.73 D ( 99 degree ) which reduced to 0.41 D ( 58 degree) at the 3rd week and 0.43 ( 21 degree) at 6 months. The mean WTR astigmatism was 4.46 D and ART astigmatism was 1.42 D on the 1st post-operative day which was significantly high ( p<0.0001). At the 3rd week and 6 months WTR astigmatism ( 1.40 D and 1.08D ) and ATR astigmatism (1.27 D and 1.10 D) showed no significant changes (p=0.69,0.97 respectively. Conclusion: Trabeculectomy with the use of 8/0 silk sutures showed significantly high 1st post-operative day SIA which nevertheless perished fast to a minimum amount at just 3 weeks. Nepal J Ophthalmol 2013; 5(10): 215-219 DOI: http://dx.doi.org/10.3126/nepjoph.v5i2.8731

scholarly journals A study of various techniques, various suture materials and important factors which determine the healing of gastro intestinal anastomosis

2019 ◽  
Vol 6 (5) ◽  
pp. 1723
Author(s):  
Rajesh Kanagala ◽  
Viswanath Nallapaneni
Keyword(s):  
Small Bowel ◽  
Large Bowel ◽  
Suture Material ◽  
Intestinal Anastomosis ◽  
Silk Suture ◽  
Intestinal Surgery ◽  
Suture Materials ◽  
Pathological Conditions ◽  
Advanced Knowledge ◽  
Resection And Anastomosis

Background: Knowledge of gastro intestinal surgery had developed gradually over centuries with much emphasis placed on suture materials and methods of anastomosis with recent advanced knowledge of gastrointestinal anastomotic healing. Objective was to study various techniques, various suture materials and important factors which determine the healing of gastro intestinal anastomosise.Methods: Resection and anastomosis was carried out in all 36 patients. The patients presented with various pathological conditions of the intestines for which resection and anastomosis was required. Data pertaining to diagnosis, type of surgery performed, and type of bowel like small or large bowel as well as outcome was recorded.Results: The disease was found to be affecting more males than females. 52.8% of the cases were operated as they had intestinal obstruction; 25% of the cases due to malignancy. The leakage was seen in one case (16.7%) that underwent anastomosis of the small bowel using single layered interrupted technique and catgut 2-0 + silk 2-0 suture material. The leakage was also seen in one more case (100%) that underwent anastomosis of the large bowel using single layered continuous technique and Vicryl 2-0 suture material. There was one case of leakage (33.3%) that underwent anastomosis of the large bowel using single layered interrupted technique Silk 2-0 suture material. One more case of leakage (10%) was seen in small bowel to large bowel anastomosis using single layered interrupted technique and Catgut + silk suture material.Conclusions: Single layered intermittent for large bowel and single layered continuous technique for small bowel are preferred techniques for prevention of leak.

scholarly journals Comparison of sewn fabric bending rigidities obtained by heart loop method: effects of different stitch types and seam directions

2020 ◽  
Vol 71 (02) ◽  
pp. 105-111
Author(s):  
Kara Sukran
Keyword(s):  
Woven Fabric ◽  
Special Importance ◽  
Bending Rigidity ◽  
Bending Properties ◽  
Rigidity Results ◽  
Loop Method ◽  
Oriented Samples ◽  
Method Effects ◽  
Reference Samples

Sewing quality is an important factor that contributes to the overall quality of an end-product. Sewing quality compro - mises different components such as bending, seam strength, seam slippage, elasticity etc. Among these components, bending has a special importance because of causing changes in appearance, sensorial comfort and drape of a garment. Therefore, in this study, effects of stitch type and seam direction on the bending rigidities of sewn fabrics were evaluated and compared. A polyester woven fabric which is suitable for sportswear was sewn with three basic stitch types (lock stitch, chain stitch and overlock stitch), in 5 different directions (warp, weft, 30°, 45° and 60° angles). As reference, samples without stitches were tested, too. Bending properties of samples were determined via heart loop method. According to the results, sewing increased the fabric bending rigidity. The degree of bending rigidity increment was dependent on the stitch type. Highest bending rigidity values were obtained for overlock stitched samples those were approximately 4 times higher when compared to non-sewn reference samples. Thickness of sewn parts was in accordance with the bending rigidity results. For oriented seams, bias sewing especially for 45˚ oriented samples, showed the most advantageous bending results. This study showed the usability of heart loop method for sewn samples via consistent results for different stitch types and seam directions.

Crystalloid Inclusions in Hepatocyte Mitochondria and Their Similarity to Cytoplasmic Crystalloids

1974 ◽  
Vol 32 ◽  
pp. 198-199
Author(s):  
Odell T. Minick ◽  
Hidejiro Yokoo
Keyword(s):  
Liver Disease ◽  
Alcoholic Liver Disease ◽  
Special Interest ◽  
Structural Variations ◽  
Mitochondrial Alterations ◽  
The Matrix ◽  
Crystalloid Inclusions ◽  
Liver Biopsies

Mitochondrial alterations were studied in 25 liver biopsies from patients with alcoholic liver disease. Of special interest were the morphologic resemblance of certain fine structural variations in mitochondria and crystalloid inclusions. Four types of alterations within mitochondria were found that seemed to relate to cytoplasmic crystalloids.Type 1 alteration consisted of localized groups of cristae, usually oriented in the long direction of the organelle (Fig. 1A). In this plane they appeared serrated at the periphery with blind endings in the matrix. Other sections revealed a system of equally-spaced diagonal lines lengthwise in the mitochondrion with cristae protruding from both ends (Fig. 1B). Profiles of this inclusion were not unlike tangential cuts of a crystalloid structure frequently seen in enlarged mitochondria described below.

Instrumentation for detecting channelling radiation in the high-voltage electron microscope

1983 ◽  
Vol 41 ◽  
pp. 318-319
Author(s):  
J. H. Butler ◽  
C. J. Humphreys
Keyword(s):  
Monochromatic Light ◽  
Incident Beam ◽  
Laboratory Frame ◽  
Relativistic Electrons ◽  
Voltage Electron ◽  
Dipole Emission ◽  
Sinusoidal Oscillations ◽  
Pass Through ◽  
Incident Beam Energy ◽  
Increasing Function

Electromagnetic radiation is emitted when fast (relativistic) electrons pass through crystal targets which are oriented in a preferential (channelling) direction with respect to the incident beam. In the classical sense, the electrons perform sinusoidal oscillations as they propagate through the crystal (as illustrated in Fig. 1 for the case of planar channelling). When viewed in the electron rest frame, this motion, a result of successive Bragg reflections, gives rise to familiar dipole emission. In the laboratory frame, the radiation is seen to be of a higher energy (because of the Doppler shift) and is also compressed into a narrower cone of emission (due to the relativistic “searchlight” effect). The energy and yield of this monochromatic light is a continuously increasing function of the incident beam energy and, for beam energies of 1 MeV and higher, it occurs in the x-ray and γ-ray regions of the spectrum. Consequently, much interest has been expressed in regard to the use of this phenomenon as the basis for fabricating a coherent, tunable radiation source.

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