Abrasion Resistance of Stereoregular Butadiene Rubber Treads as a Function of Tire Operating Conditions

1968 ◽  
Vol 41 (3) ◽  
pp. 685-691
Author(s):  
V. F. Evstratov ◽  
G. N. Buiko ◽  
N. L. Sakhuovskii ◽  
N. M. Arenzon ◽  
A. I. Karmanova
Keyword(s):  
Abrasion Resistance ◽  
Operating Conditions ◽  
Butadiene Rubber ◽  
Test Conditions ◽  
Different Types ◽  
Group A ◽  
Group B ◽  
Selection Of ◽  
Automobile Tires

Abstract In operating tires on Group A roads, the abrasion resistance of SKD/SBR and SKD/NR blends is substantially higher than that of SKS-30 ARKM-15. The abrasion index of butadiene rubbers increases with the severity of the test conditions, as in operating on mountain roads, with partial braking and acceleration. In operating tires on Group B and V roads (for example, in quarries), the abrasion index of SKD rubbers, particularly those with high SKD content, decreases considerably as a result of increased chipping and cutting of the tread pattern. In summer, the superiority of BR rubbers over SKS-30 ARKM-15 in abrasion resistance is less apparent than in winter. This is particularly characteristic for SKD/NR blends. For automobile tires of different types and sizes, the selection of composition and properties of treads in which SKD is used should be carried out in such a way as to take into account operating conditions.

scholarly journals Importance of initial fracture crack width in minimally dislocated fractures of humeral lateral condyle in children for evaluation of fracture stability and treatment choice

2009 ◽  
Vol 137 (3-4) ◽  
pp. 179-184
Author(s):  
Zoran Rakonjac ◽  
Radivoj Brdar
Keyword(s):  
Crack Width ◽  
Lateral Condyle ◽  
Intraarticular Fracture ◽  
Number Of Children ◽  
Fracture Crack ◽  
Choice Of Treatment ◽  
Group A ◽  
Group B ◽  
Fracture Stability ◽  
Selection Of

Introduction. The fracture of the external condyle is the most common fracture of the distal end of the humerus. This is an intraarticular fracture, which, if not properly treated, can cause serious complications, difficult to treat. Objective. To define the importance of the initial width of the fracture crack for the evaluation of stability of the minimally dislocated fractures of the humeral lateral condyle and for the selection of the method of treatment. Methods. The target group included the children with minimally dislocated fractures or fractures of uncertain stability. The number of children was 35. On the grounds of the initial width of the fracture crack, two groups were formed. Group A comprised 25 (71.4%) examinees with the initial width 2-2.9 mm. Group B comprised 10 (28.6%) examinees with the initial width 3-3.9 mm. Measuring was performed on the PA and profile radiographies. A higher value was taken for analysis. The control of fracture crack width was done by systematic radiographies in the following time intervals: the first, third, seventh and the fourteenth day in group A, and the first and third day (1B and 3B) in group B, since the fracture occurrence. Results. The analysis of the results in group A showed the following: the enlargement of dislocation between 1-3 days was significant (p<0.05). Between 3-7 and 7-14 days, there was no significant enlargement of dislocation (p>0.05). Fractures were stable and treated nonsurgically. In group B, the enlargement of dislocation was significant until the third day (p<0.05). These fractures were unstable, there was a great risk for secondary dislocations and they were to be duly fixed. Initial widths of these groups varied significantly (p<0.05). Conclusion. The initial width of the fracture crack is important for the evaluation of the fracture stability, the evaluation of the risk for the creation of secondary dislocations and for the choice of treatment. The upper limit of the fracture crack width which influenced the selection of the method of treatment was 2.5 mm.

scholarly journals Comparison of Fracture Resistance of Teeth Presenting non-carious Cervical Lesions, Restored with Different Composite Materials

2020 ◽  
Vol 57 (1) ◽  
pp. 299-305
Author(s):  
Ruxandra Margarit ◽  
Livia Alice Tanasescu ◽  
Dana Bodnar ◽  
Camelia Gabriela Ion ◽  
Mihai Burlibasa ◽  
...  
Keyword(s):  
Composite Materials ◽  
Fracture Resistance ◽  
Mean Value ◽  
P Value ◽  
Cervical Lesions ◽  
Nano Composite ◽  
Commercial Grade ◽  
Different Types ◽  
Group A ◽  
Group B

The aim of our study was to compare the fracture resistance of teeth presenting non-carious cervical lesions restored with different types of esthetic composite materials. 20 extracted unspoiled maxillary first molars were mechanically cleaned and immersed in saline solution containing 0.1% thymol at 4�C for a period of 48 hours. Cervical cavities with a cervical-occlusal diameter of 2 mm and a mesial-distal diameter of 3mm were filled with ormocer, flow nano-composite, nano-composite and compomer. Fracture resistance was tested with a universal loading machine (Lloyd Instruments), with a maximum force of 5 kN and a crosshead speed of 1.0 mm/min; the authors used NEXYGEN Data Analysis Software and ANOVA method. For the group A (commercial grade ormocer), the smallest load that determined the sample failure was 650 N and the highest load was 1050 N, the mean value being 858 N � 150.89 N. For the group B (commercial grade flow nano-composite), the smallest load is 530 N, the highest load is 800 N, mean value being 654 N � 112.6 N. For the group C (commercial grade nano-composite), the smallest load is 680 N, the highest load is 1200 N, mean value being 926 N � 209.35 N. For the group D (commercial grade compomer), the smallest load is 1100 N, highest load is 1250N, mean value being 1180 N � 62.04 N. A p value of 0.000311 (p[0.05) shows that there are significant differences between the four groups. Conclusions. The best fracture resistance of teeth presenting non-carious cervical lesions, restored with different types of esthetic composite materials is assured by the compomer, followed by the nano-composite, which proved to be superior to ormocer. The flow nano-composite gives the lowest fracture resistance.

scholarly journals Antibiotic usage rates in bacterial versus nonbacterial diseases: a new way to monitor hospital-acquired infections in children: a retrospective case analysis

2020 ◽  
Vol 7 (11) ◽  
pp. 2176
Author(s):  
Jayendra R. Gohil ◽  
Chintu C. Chaudary ◽  
Sheena D. Sivanandan
Keyword(s):  
Antibiotic Usage ◽  
Retrospective Case ◽  
Hospital Acquired Infections ◽  
Group A ◽  
Added Benefit ◽  
Reduction Of Mortality ◽  
Group B ◽  
The Cost ◽  
Hospital Acquired ◽  
Selection Of

Background: While treating children, the selection of antibiotics, when indicated, should be from the point of its effectiveness, safety, suitability, and cost. However, this flow of action does not take place in all cases. Aim of the study was to assess the antibiotic usage in admitted children and mortality.Methods: The case records between January to July 2012 in children wards was evaluated for the use of antibiotics. Patients were grouped into; group A- ‘must use' antibiotic in all, and group B- where antibiotics are not indicated.Results: There were 1852 admissions, including 719 Thalassemia cases. Antibiotic usage was 63% in 1133 cases after excluding thalassemia. Out of 1133 cases, 423 were in group A and 710 cases were in group B. In group B the antibiotic usage was 41%. The mortality was 6.6% and 4.8% in group A and B. Inside group B, mortality was 5.9% versus 4.0% in those administered versus not administered, antibiotics.Conclusions: There was no increase in mortality in patients in whom antibiotics were not prescribed, and no added benefit of prescribing antibiotics was observed in nonbacterial group B disease patients. The mortality was similar in both the groups. In nonbacterial group B, the antibiotics did not offer any advantage in the reduction of mortality, but increased the cost of the treatment, and possibly the chance of development of drug resistance and adverse events. When analysing the hospital antibiotic usage, only the nonbacterial diseases should be considered to get a true picture of the inappropriate prescription of antibiotics.

Textile Performance Properties of Cotton Fabric Treated with Selected Flame-Retarding Finishes

1977 ◽  
Vol 47 (5) ◽  
pp. 365-371 ◽  
Author(s):  
Stanley P. Rowland ◽  
John S. Mason
Keyword(s):  
Cotton Fabric ◽  
Abrasion Resistance ◽  
Breaking Strength ◽  
Superior Performance ◽  
Disodium Hydrogen Phosphate ◽  
Performance Properties ◽  
Different Types ◽  
The Individual ◽  
Medium Weight ◽  
Selection Of

Seven different types of flame-retarding finishes were applied to light-to-medium weight cotton fabric at add-ons appropriate to pass the DOC FF 3–71 test. The finishes studied were based on tetrakis(hydroxymethyl)phosphonium chloride (THPC), neutralized THPC (THPOH), Fyrol 76, and Pyrovatex CP. The specific finishes were: THPOH-NH3, THPOH-urea-trimethylolmelamine, Proban (THPC-urea precondensate)-NH3, THPC-urea-disodium hydrogen phosphate, Fyrol 76, Fyrol 76-N-methylolacrylamide, and Pyrovatex CP-methylolmelamine. Textile performance properties are reported as a function of add-on of each type of finish; strengths and abrasion resistance of the finished fabrics are considered and discussed as a function of resilience. General trends of decreasing strength and abrasion resistance with increasing resilience were observed for these flame-retardant fabrics. Within this trend there is latitude for selection of finishes that will provide superior performance in the individual textile property such as abrasion resistance, breaking strength, and tearing strength.

scholarly journals A Comparative in vivo Study of Semi-constrained and Unconstrained Cervical Artificial Disc Prostheses

2019 ◽  
Vol 184 (Supplement_1) ◽  
pp. 637-643 ◽  
Author(s):  
Hoon Choi ◽  
Jamie L Baisden ◽  
Narayan Yoganandan
Keyword(s):  
In Vivo Model ◽  
Artificial Disc ◽  
Disc Space ◽  
Cervical Arthroplasty ◽  
Healthy Female ◽  
Different Types ◽  
Group A ◽  
Group B ◽  
Anterior Migration

Abstract Purpose The objective of this study is to directly compare different types of cervical artificial disc implants using an in vivo model capable of simulating the axial load on a neck that is similar to the human neck. Methods Cervical arthroplasty was performed at C3-4 in 14 healthy female adult Alpine goats. The goats were divided into three groups. Group A received Bryan (unconstrained one-piece design); Group B received ProDisc-C (semi-constrained two-piece design); and Group C received Mobi-C (unconstrained three-piece design) artificial discs. The goats were monitored in a veterinary unit for 6 months with radiography at regular intervals. Results Each goat tolerated cervical arthroplasty well and had satisfactory placement of their implant per intra-operative radiography. Implants monitored in Group A demonstrated no migration. One out of five implants in Group B experienced anterior migration at 3 months. In Group C, anterior migration and disintegration occurred in all four implants, with migration occurring during the first postoperative week in three implants and after 5 weeks in the fourth. Conclusions Unconstrained multi-piece artificial cervical discs may be prone to anterior migration and extrusion out of the disc space. This outcome deserves attention in individuals with a hypermobile neck and/or an occupation involving the use of a head-supported mass, such as helmets.

scholarly journals Does Implant-Abutment Interface affect Marginal Bone Levels around Implants?

2019 ◽  
Vol 13 (01) ◽  
pp. 047-052 ◽  
Author(s):  
Eser Elemek ◽  
Artun Urgancioglu ◽  
Janberd Dincer ◽  
Altug Cilingir
Keyword(s):  
Bone Loss ◽  
Dental Implants ◽  
Marginal Bone Loss ◽  
Single Crown ◽  
Implant Abutment ◽  
Different Types ◽  
Group A ◽  
Group B ◽  
Switch Group

Abstract Objective The use of dental implants with different types of surface roughness and implant-abutment interface has brought about a situation of marginal bone loss. Therefore, the aim of this study was to analyze and compare marginal bone levels of different types of osseointegrated dental implants with platform switch (Group A: Ankylos, Mannheim, Germany) and platform match (Group B: Dentsply Xive, Mannheim, Germany, and Group C: MIS Implant Technologies, Karmiel, Israel). Materials and Methods One hundred and seven patients (52 men and 55 women) with a mean age of 54.79 (standard deviation ± 12.35) years and a total of 321 dental implants (Group A, n = 198; Group B, n = 58; and Group C, n = 65) placed in a private practice between April 2006 and May 2015 were retrospectively analyzed. In addition to demographic information and implant characteristics, marginal bone levels were evaluated by Image J (Wayne Rasband, National Institute of Health, Maryland) program. Results The mean age of all patients was 54.79 ± 12.35 years, and 51.5% of them were women. Implants supporting fixed bridge were most commonly used in all groups (65%), whereas only 20% were restored with a single crown and 15% with overdentures. In total, 47.5% of all implants showed no marginal bone loss. Mean bone loss in Group A was significantly lower (0.81 ± 1.60 mm) as compared to Group B (1.58 ± 1.59 mm) and Group C (1.18 ± 1.36) (p < 0.005). Conclusion Among different types of dental implants, platform switch seems to preserve marginal bone levels and increase the long-term success of dental implants.

scholarly journals Comparing hemostatic and adhesion prevention effects of different types of nasal packings used post-septoplasty viz medicated gauze packing, glove finger packing and merocel packing

2012 ◽  
Vol 18 (2) ◽  
pp. 129-132
Author(s):  
Owais Mattoo ◽  
Rahil Muzaffar ◽  
Anees Mir ◽  
Manzoor A Malik ◽  
Shakil Ahmed ◽  
...  
Keyword(s):  
Adhesion Formation ◽  
Nasal Packing ◽  
Adhesion Prevention ◽  
Gauze Packing ◽  
Different Types ◽  
Glove Finger ◽  
Group A ◽  
The Difference ◽  
Group B ◽  
Hemostatic Effects

Aim: To compare the adhesion prevention and hemostatic effects of different types of nasal packing viz. medicated gauze packing, glove finger packing and merocel packing. Study Design: Prospective Study, in which 105 patients were, enrolled with effect from September 2011 to March 2012.Methods: This study was done in postgraduate department of ENT - HNS in Govt. Medical College, Srinagar. 105 patients undergoing septoplasty were randomly distributed in three groups, Group A, Group B, and Group C. Group A patients were packed postoperatively with medicated gauze packing, Group B with glove finger packing and Group C with merocel packing. Patients were then examined and regularly observed and followed for post-septoplasty hemorrhage and adhesions.Results: The average number of cotton balls used to clean the blood soakage on day one was 10 in Group A, 13 in Group B and 15 in Group C. On comparing the results of medicated gauze packing with merocel packings, the difference was not statistically significant(p<0.20), though apparently conventional anterior nasal packing (ANP) appeared to be better hemostatic than other types of packings. At 4 weeks postoperatively, the number of patients who developed adhesions were 10 (28.6%) in Group A, 8 (22.9%) in Group B and none (0 %) in Group C. On comparing the results of merocel packing with conventional ANP with highest rate of adhesion formation, the difference was statistically significant (p<0.002). Also on an average minimal number of paracetamol tablets (Dosage Strength 500 mg) were consumed by patients whose noses were packed with merocel (8 tablets) as compared to conventional ANP (13 tablets) and glove finger (8 tablets) over a period of one week.Conclusions: Hemostatic effects were best observed with medicated gauze packing, though the difference was not statistically significant. Adhesion formation which is one of the most important determinants of success of septoplasty is best prevented by merocel packing. If good expertise is observed during septoplasty with proper sterilization technique, postseptoplasty hemorrhage is quite uncommon and adhesion prevention becomes the single most important factor. Merocel packing should thus be carried out in almost all cases. In cases where postoperative bleeding is suspected, classical medicated gauze packing should be done. The morbidity associated with postoperative pain was minimal with merocel packing. DOI:http://dx.doi.org/10.3329/bjo.v18i2.11989 Bangladesh J Otorhinolaryngol 2012; 18(2): 129-132

scholarly journals Comparison of postoperative liver function between different dissection techniques during laparoscopic cholecystectomy

2020 ◽  
pp. FSO462
Author(s):  
Tagleb S Mazahreh ◽  
Abdelwahab J Aleshawi ◽  
Nabil A Al-Zoubi ◽  
Mohammad Altabari ◽  
Qusai Aljarrah
Keyword(s):  
Laparoscopic Cholecystectomy ◽  
Liver Function ◽  
Aspartate Aminotransferase ◽  
Alanine Aminotransferase ◽  
Total Bilirubin ◽  
Liver Function Tests ◽  
Different Types ◽  
Group A ◽  
Dissection Techniques ◽  
Group B

Aim: In this study, we investigated and compared the effect of different types of dissector (Maryland vs Hook) on changes in liver function tests (LFTs) after laparoscopic cholecystectomy. Patients & methods: The enrolled patients were divided into two groups. Group A patients underwent dissection by Maryland dissecting forceps, group B by Hook dissecting instrument. LFTs were measured preoperatively and at 1 day and 1 week, postoperatively. Results: For both Maryland and Hook dissection, the 1-day postoperative values for total bilirubin, alanine aminotransferase and aspartate aminotransferase were significantly higher than the preoperative values. Also, there were no statistical differences between Hook and Maryland. Conclusion: The elevation of LFTs seems to be attributed to other factors.

Distinguishing Between Fresh and Frozen-thawed Smoked Salmon: Histology to Detect Food Adulteration in High-Value Products

2019 ◽  
Vol 83 (1) ◽  
pp. 52-53 ◽  
Author(s):  
MARZIA PEZZOLATO ◽  
ELISA BAIONI ◽  
CRISTIANA MAURELLA ◽  
KATIA VARELLO ◽  
SERENA MEISTRO ◽  
...  
Keyword(s):  
High Performance ◽  
Accurate Method ◽  
Food Adulteration ◽  
Smoked Salmon ◽  
Different Types ◽  
Group A ◽  
Quality Of Products ◽  
Group B ◽  
Sensitivity Specificity

ABSTRACT The issue of food safety has acquired increased importance, and fraud is a major concern for the food industry. Among different types of food adulteration, there is the sale of frozen-thawed smoked salmon product as fresh, which not only decreases the quality of products but also misleads consumers and may involve associated health risks. In response to this problem, we tested the performance of histology to identify smoked salmon as fresh or frozen-thawed as a valid analytical method, so food business operators and official controllers can reliably and correctly classify the storage state of the product. Three groups of samples were prepared: group A (n = 36), fresh samples; group B (n = 36), frozen at −18°C for 30 days; and group C (n = 36), stored at −3°C for 30 days after packaging. Two histopathologists examined all samples in blind evaluations and classified them as fresh or frozen-thawed. Sensitivity, specificity, and interrater agreement were calculated. Results show high performance with the test: 80.6% sensitivity (95% confidence intervals [CI]: 64 to 91.8%); 95.6% specificity (95% CI: 89.1 to 98.8%); and Cohen's kappa was 0.81 (95% CI: 0.64 to 0.98%). Histology is a reliable and highly accurate method to differentiate fresh from frozen-thawed smoked salmon and could be used by the industry and official controllers to verify the labeling of the commercial product. HIGHLIGHTS

Selection of the optimal first ear for sequential bilateral cochlear implantation in children

2021 ◽  
pp. 014556132110640
Author(s):  
Hantai Kim ◽  
Jungho Ha ◽  
Eun Sol Gil ◽  
Jeong Hun Jang ◽  
Hun Yi Park ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Cochlear Implantation ◽  
Speech Intelligibility ◽  
Test Results ◽  
Monosyllabic Word ◽  
Intelligibility Test ◽  
Group A ◽  
Study Population ◽  
Group B ◽  
Selection Of

Objectives When there is a difference in hearing on both ears, where to perform the first cochlear implantation (CI) becomes an important issue. The purpose of the study was to evaluate which ear should be chosen for the first implantation in sequential bilateral CI with a long inter-implant period. Methods The study population consisted of 34 severe-to-profound sensorineural hearing loss pediatrics with the inter-implant period of ≥3 years between the first CI (CI-1) and the second CI (CI-2) before the age of 19 (mean of inter-implant period: 7.1-year). The patients were classified into Group A (CI-1 was performed on the ear with better hearing), Group B (CI-1 on the ear with worse hearing), or Group C (symmetrical hearing in both ears). Speech intelligibility test results were compared between the groups. Results The monosyllabic word scores of CI-1 were excellent in Groups A (91.7±7.9%) and B (92.5±3.6%) but slightly lower in Group C (85.7±14.9%) before the second implantation ( P = .487). At 3 years after the second implantation, all groups demonstrated excellent scores in the bilateral CI condition (95.9±3.0% in Group A; 99.1±.8% in Group B; 97.5±2.9% in Group C, P = .600). However, when the patients were tested in using CI-2 only in Groups A and B after using bilateral CI for 3 years, the scores were inconsistent in Group A (79.6±23.9%; range: 22.2-94.4%), while those were higher and more constant in Group B (92.9±4.8%; 86.8-100.0%). Conclusions The first CI is strongly recommended to perform on a worse hearing ear if they had different hearing levels between ears. Even with the first CI on a worse hearing ear, its performance never deteriorates. In addition, if they receive the second CI several years later, it will be likely that the second one functions better.

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