• Clinics in Shoulder and Elbow
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• v.17 no.4
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• pp.166-174
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• 2014

Background: Our study was to determine the effect on shoulder isokinetic muscle strength and muscle endurance in isolated full-thickness supraspinatus tendon tear and combined other rotator cuff tear. Methods: Total of 81 male patients (mean age $57.8{\pm}7.4$ years) who were diagnosed as a full-thickness supraspinatus tendon tear were included. They were classified into isolated or combined tear. The isokinetic muscle strength and muscle endurance were measured using the Biodex multi-joint system $PRO^{(R)}$ (Biodex Medical Systems, Shirley, NY, USA) in following movements: shoulder abduction, adduction, flexion, extension, external rotation, and internal rotation. Then, the difference in muscle function according to the type of tears were assessed. Fifty-seven patients had isolated supraspinatus tendon (mean age $56.9{\pm}7.3$ years). They were classified into either anteroposterior tear or modified mediolateral tear. The size were measured using T2-weighted magnetic resonance imaging scans in sagittal plane. Results: Between subjects categorized into the type of tear, we found significant inter-categorical differences in isokinetic muscle strength during abduction, adduction, flexion, extension, and internal rotation, and in muscle endurance during flexion, extension, and internal rotation. Anteroposterior diameter tear, we did not show significant differences in either isokinetic muscle strength or muscle endurance during any movements. However, with modified mediolateral diameter, we found significant differences with isokinetic muscle strength during adduction, and in muscle endurance the external rotation and internal rotation. Conclusions: We found that a supraspinatus tendon tear associated with more numbers of rotator cuff tears has lower isokinetic muscle strength and muscle endurance than a tear found alone.

• Fashion & Textile Research Journal
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• v.21 no.2
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• pp.203-208
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• 2019

This paper considers the moisture permeability and fashion in the upper fabrics of cotton fabric shoes woven into various tissues and properties measured to examine the use as upper fabrics. We measured the tissues of the manufactured upper fabric are 1/3 twill, $4{\times}4$ weft rib, Maya, Triple, Deformed twill design (DTD), Diamond tissues and tear strength, tensile strength, breaking elongation, stretching under load at 100N, stitch tear resistance, and fastness. In the case of $4{\times}4$ weft rib, the tear strength and tensile strength were excellent; however, the elongation and stitch tear resistance at 100N load were less than the standard value. DTD fabrics are characterized by physical properties in the warp direction that are superior to those in the weft direction; however, the tear strength and tensile strength in the weft direction are less than the standard value. The 1/3 twill fabrics showed high tensile strength value and stitch tear resistance value in the warp direction; however, toughness, the main property of the shoe upper, was below the standard value. Triple and diamond fabrics, which have a significant effect on the performance of the shoe upper fabric, also had less than the standard value of tear strength. Maya upper fabric for shoes has better properties than other upper fabrics except for the elongation at break, and the stitch tear resistance has a value of 178% in the warp direction and 214% in the weft direction compared to the standard value. Therefore, the Maya fabric showed the possibility of being used as an upper textile for shoes.

• Journal of Welding and Joining
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• v.13 no.2
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• pp.106-114
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• 1995

The characteristics of adhesive bonded joint of steels for automobile were investigated. Shear and tear strength were tested and analyzed for the joints of cold rolled steel sheets bonded with three kinds of epoxy and urethane based adhesive. The results showed that the tensile shear strength and the tear strength of adhesive joint were affected by the shape of adhesive joint such as the length and width of adhesive joint. The thickness of adhesive layer was very important factor affecting the bonding strength. The shear strength increased with decrease of the thickness of adhesive layer, while the tear strength decreased as the thickness of adhesive layer decreased. In comparison with the strength of spot welded joint, the shear strength of adhesive Joint was higher than that of spot welded joint, but the tear strength of adhesive Joint was lower than that of spot welded joint.

• Textile Coloration and Finishing
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• v.21 no.3
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• pp.1-9
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• 2009

Polycarboxylics acids are used as crosslinking agents for cotton cellulose to produce durable finished press cotton fabric. It has been observed that the strength of the cotton fabric treated with polycarboxylic acids showed significant reduction as a result of the crosslinking process. The effect of acid-catalyzed depolymerization on the tear strength of cotton fabric is investigated by evaluating the cotton fabric treated by succinic acid, which does not crosslink cotton cellulose and form little ester on the cotton fabric. We find that the tear strength of cotton fabric treated with succinic acid decreases at elevated temperature due to acid-catalyzed depolymerization of cellulose. The magnitude of fabric strength reduction increases as the acid concentration increases. At a constant acid concentration, it increases as the curing temperature and time increases. It decreases as the pH of the acid solution increases. We also find that the dissociation constant of an acid also has a significant effect on the fabric strength reduction. The magnitude of fabric tear strength reduction increases as the acid dissociation constant decreases.

• Elastomers and Composites
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• v.59 no.1
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• pp.34-41
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• 2024

In this study, the effects of the type and content of silica on the mechanical and tear properties of chloroprene rubber (CR), which is mainly used as a jacket material for mining cables, were studied. The crosslinking density (ΔM) and reinforcing factor (α_f) defined using cure characteristics increased with increasing silica content, whereas the cure rate decreased. The hardness, tensile strength, and modulus of the CR compounds increased depending on the silica content and structural development. The reinforcing behavior of the silica-filled CR compounds according to the silica type and content showed the best fit with the Thomas equation of the predictive model. Tear strength was evaluated using two standard test methods, ASTM D470 and DIN VDE 0472-613, and the results were compared. The tear strength increased as the silica content increased, regardless of the test method, and the different tear strengths obtained by the two standard test methods showed a linear relationship with each other, indicating a high correlation.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.237-242
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• 2012

The purpose of this study was (a) to develop carbon nanotube-based shock absorbers for reducing potentially harmful impact forces and excessive foot pronation, and (b) to briefly determine how the effects of carbon nanotube-based shock absorbers on biomechanical variance during drop landing. A university student(age: 24.0 yrs, height: 176.2 cm, weight: 679.5 N) who has no musculoskeletal disorder was recruited as the subject. Hardness, specific gravity, tensile strength, elongation, 100% modulus, tear strength, split tear strength, compression set, resilience, vertical GRF, and loading rate were determined for each material. For each dependent variable, a descriptive statistics was used for different conditions. The property test results showed that tensile strength, tear strength, split tear strength, compression set, and resilience in carbon nanotube-based shock absorbers were greater than general Ethylene Vinyl Acetate(EVA). These indicated that resistance against variable strength in developed carbon nanotube-based shock absorbers were greater than general EVA. In vertical GRF of CNTC was less than those of EVA during drop landing and loading rate of CNTC was greater than EVA. It seems that the use of CNT can be a effective way of reducing and controlling shock from impact.

• The Journal of Advanced Prosthodontics
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• v.6 no.2
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• pp.115-120
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• 2014

PURPOSE. The aim of this in vitro study was to evaluate the effect of aging on the tear strength and cytotoxicity of four soft denture lining materials. MATERIALS AND METHODS. Four commonly used soft denture lining materials, (Coe-Comfort$^{TM}$ GC America Inc., Alsip, IL, USA; Coe-SOFT$^{TM}$ GC America Inc., Alsip, IL, USA; Visco-gel Dentsply Caulk Milford, DE, USA; and Sofreliner Tough M Tokuyama Dental Corporation Tokyo, Japan) were selected. Sixty trouser-leg designed specimens per lining material were fabricated using a stainless steel mold for tear strength testing. The specimens were divided into non-thermocycling and 1000-, and 3000-thermocycling groups. For the cytotoxicity test, twenty-four disk shaped specimens per material were fabricated using a stainless steel mold. The specimens were soaked in normal saline solution for 24 h, 48 h and 72 h. Cytotoxicity was measured by XTT assay in L929 mouse fibroblasts. Data were analyzed by two way analysis of variance and Dunnett's test (P<.05). RESULTS. Before thermocycling, Sofreliner Tough M ($10.36{\pm}1.00N$) had the highest tear strength value while Coe-Comfort$^{TM}$ ($0.46{\pm}0.10N$) had the lowest. After 3000 cycles, Sofreliner Tough M ($9.65{\pm}1.66N$) presented the highest value and Coe-Comfort$^{TM}$ ($0.42{\pm}0.08N$) the lowest. Sofreliner Tough M, in all incubation periods was the least toxic with significant differences compared to all other materials (P<.05). Coe-Comfort$^{TM}$, Coe-$SOFT^{TM}$, and Sofreliner Tough M did not show any significant differences within their material group for all incubation periods. CONCLUSION. This in vitro study revealed that aging can affect both the tear strength and cytotoxicity of soft denture materials depending on the composition.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.4
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• pp.65-72
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• 2009

We investigated the effect of polyelectrolyte types in Layer-by-Layer multilayering and furnish combination on physical properties of paper. Handsheets were made from pulp fibers with different polyelectrolytes composition, and their density, formation, tensile strength, strain, tear strength and burst strength were evaluated. The density of handsheet was slightly decreased by polyelectrolyte multilayering. Formation did not show a significant change, but all mechanical properties were increased by polyelectrolyte multilayering. Remarkable improvement in tensile and tear strengths was obtained when pulp fibers were treated with cationic starch and poly styrene 4-sulfonate. Irrespectively of final ionicity of pulp fiber, tensile index, strain and tear strength of paper could be improved simultaneously by polyelectrolyte multilayering.

• Elastomers and Composites
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• v.48 no.3
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• pp.241-248
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• 2013

Polyester type polyurethane foam has low hydrolysis resistance. It was overcome with addition of acrylic polyol by quasi prepolymer method. Tensile strength and hardness of polyurethane foam contained acrylic polyol was increased with increasing of acrylic polyol contents. But split tear strength and tear strength was slightly changed. Hydrolysis resistance of polyurethane foam was measured by loss % of tensile strength. It was improved with increasing of acrylic polyol contents from 25.5g to 102g.

• Clinics in Shoulder and Elbow
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• v.19 no.2
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• pp.90-95
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• 2016

Background: The aim of this study was to investigate the correlation between the type of subscapularis tendon tears diagnosed during arthroscopy and the outcomes of physical tests and of isokinetic muscle strength tests. Methods: We preoperatively evaluated physical outcomes and isokinetic muscle strength of 60 consecutive patients who underwent an arthroscopic rotator cuff repair and/or subacromial decompression. We divided the patients into five groups according to the type of subscapularis tear, which we classified using Lafosse classification system during diagnostic arthroscopic surgery. Results: When we performed a trend analysis between the outcomes of the physical tests and the severity of subscapularis tendon tear, we found that both the incidence of positive sign of the collective physical tests and that of individual physical tests increased significantly as the severity of the subscapularis tear increased (p<0.001). Similarly, the deficit in isokinetic muscle strength showed a tendency to increase as the severity of subscapularis tear increased, but this positive correlation was statistically significant in only the deficit between those with Lafosse type II tears and those with Lafosse type III tears. Conclusions: Although no single diagnostic test surpasses above others in predicting the severity of a subscapularis tear, our study implies that, as a collective unit of tests, the total incidence of the positive rate of the physical tests and the extent of isokinetic strength deficit may correlate with severity of subscapularis tears.