Integral equations for the problem of wave diffraction on a flat strip: alternative representation

This study investigates an effective method for solving one class of integral equations. It addresses various two dimensional problems related to do diffraction theory by metal screens, which are reduced to these integral equations. A novel approach for solving this class of integral equations is proposed. The study foceses on investigating diffraction on a strip using a combination of analytical and numerical methods and the results are obtained through simulation.Publisher's Versio

Implant Bed Preparation with an Erbium, Chromium Doped Yttrium Scandium Gallium Garnet (Er,Cr: YSGG) Laser Using Stereolithographic Surgical Guide

INTRODUCTION: Implant bed preparation with laser is taken into consideration owing to the increased interest in use of lasers in hard tissue surgery. The purpose of this study is to determine the deviations in the position and inclination between the planned and prepared implant beds with Erbium, Chromium doped Yttrium Scandium Gallium Garnet (Er,Cr: YSGG) laser using stereolithographic (SLA) surgical guides.METHODS: After 3-dimensional (3D) imaging of six sheep lower jaws, computed tomography (CT) images were transformed into 3D models. Locations of implant beds were determined on these models. Two implant beds in each half jaw were prepared with an Er,Cr:YSGG laser system and a conventional drilling method using a total of 12 SLA surgical guides. A new CT was taken to analyze the deviation values between planned and prepared implant beds. Finally, a software program was used to superimpose the images on 3D models, then the laser and conventional drilling groups were compared.RESULTS: Differences of mean angular deviations between the planned and prepared implant beds were 5.17±4.91° in the laser group and 2.02±1.94° in the conventional drilling group. The mean coronal deviation values were found to be 0.48±0.25 mm and 0.23±0.14 mm in the laser group and conventional drilling group, respectively. While the mean deviation at the apex between the planned and prepared implant beds were 0.70±0.26 mm and 0.26±0.08, the mean vertical deviations were 0.06±0.15 mm and 0.02±0.05 mm for the laser group and the conventional drilling group, respectively.CONCLUSION: It is possible to prepare an implant bed properly with the aid of Er,Cr:YSGG laser by using SLA surgical guide

The effect of social support, depression, and illness perception on treatment adherence in patients with multiple sclerosis

Objective: This study was planned to determine the treatment adherence levels of multiple sclerosis (MS) patients and the factors affecting treatment adherence. Patients and Methods: This descriptive and cross-sectional study was conducted with 211 people with MS. Data for this study was obtained through face-to-face interviews with MS patients who presented at the neurology outpatient clinics of two university hospitals between April and October 2018. The Morisky, Green, and Levine Adherence Scale, Beck Depression Inventory, Multidimensional Perceived Social Support Scale, and the Illness Perception Scale were used in data collection. Results: The mean age of the sample was 40.03 +/- 10.82, and 70.1% were female. Treatment adherence was not good in half of the patients (51.7%). Patients with good adherence were found to have higher Multidimensional Perceived Social Support Scale scores (p0.05). Conclusion: Treatment adherence was insufficient in half of the MS patients. According to our findings, ensuring more cooperation with the families of patients, which constitute the strongest source of social support, increasing treatment adherence can be suggested as well as screening patients with regard to depressive symptomology during follow-up

Sustainable and Renewable Energy Power Plants Evaluation by Fuzzy TODIM Technique

Sustainable and renewable energy systems are an effective solution to depletion of fossil energy resources and prevent serious environmental problems resulted from energy production. Turkey has rich renewable energy potential due to its geographical features. In this regard, the government puts emphasis on increasing renewable energy utilization rate in meeting energy demand of the country. Therefore encouragement policies are implemented in this field and energy investors are supported economically. In his study, we aimed to find out the best performing sustainable and renewable energy alternative and thus to guide decision makers on energy investments. Therefore we evaluated four energy power plant types, which are solar, wind, hydroelectric and landfilled gas (LFG). For the evaluation of the alternatives, there are many factors to consider and multicriteria decision making (MCDM) methods are an appropriate approach for this issue. In this regard, we determined 22 evaluation criteria in technical, economical and environmental aspect and applied TODIM technique. It is based on prospect theory and the most significant difference from the other MCDM methods is to deal with risk in decision-making. In order to cope with vagueness and uncertainty in this evaluation process, we integrated fuzzy sets into the system. Finally we evaluated the results obtained and presented a sensitivity analysis at the end

The effect of periodontal therapy on neopterin and vascular cell adhesion molecule-1 levels in chronic periodontitis patients with and without acute myocardial infarction: a case-control study

The presence of neopterin in gingival crevicular fluid (GCF) is a marker for local and acute immune activation, and the presence of vascular cell adhesion molecule (VCAM-1) in GCF is accepted as a marker for chronic vascular inflammation. Objectives: This study aimed to evaluate effects of periodontal treatment on GCF levels of neopterin and VCAM-1 in patients with chronic periodontitis (CP) with acute myocardial infarction (AMI) compared with systemically healthy CP patients. Material and methods: Sixty subjects (20 CP patients with AMI, 20 healthy CP patients, and 20 healthy controls) were included. GCF samples were analyzed at baseline and after 3 and 6 months, and the probing pocket depth (PD), clinical attachment level (CAL), bleeding on probing, gingival (GI) and plaque (PI) indices were recorded. We determined neopterin and VCAM-1 levels (concentration and total amount) using enzyme-linked immunosorbent assay (ELISA). No significant differences were seen between the AMI+CP and CP groups for PI, GI, GCF levels of neopterin and VCAM-1 at baseline. Results: The number of teeth with 5 mm≤CAL<7 mm and CAL≥7 mm were significantly increased in the AMI+CP group at baseline. There were no significant differences between the AMI+CP and CP for PI, CAL, GCF volumes, and the AMI+CP group had the highest clinical improvement in the number of teeth with 5 mm≤CAL<7 mm at the sixth month. There were significant positive correlations between clinical periodontal inflammation and the presence of neopterin and VCAM-1 in GCF prior to and following periodontal treatment, and between the GCF volume and clinical parameters. Conclusions: Data suggest that the total amount and concentration of neopterin and VCAM-1 in GCF seemed to be closely associated with periodontal disease severity in CP patients with AMI. Moreover, the results of our study demonstrate that the past periodontal status is potentially correlated between groups, with similar periodontal disease severity

DETERMINATION OF NUTRITION KNOWLEDGE LEVELS OF 9–12 AGE GROUP TENNIS ATHLETES

Objective: This study was aimed to determine the nutritional knowledge levels of 9–12 age group tennis athletes according to the variables of age, gender, year of sports and parental education.Material and Method: Based on this purpose, the research sample consists of a total of 171 tennis athletes in the 9–12 age group, competitors n: 91 girls and n: 80 boys. In the collection of the data and determination of the nutritional knowledge levels of the athletes, a 5-scale form consisting of 26 questions that Laurie et al. (2003) used in their research was taken into consideration. The obtained data were transferred to electronic media and analyzed in SPSS 22.0 package program

Specified Species in Gingival Crevicular Fluid Predict Bacterial Diversity

BACKGROUND: Analysis of gingival crevicular fluid (GCF) samples may give information of unattached (planktonic) subgingival bacteria. Our study represents the first one targeting the identity of bacteria in GCF. METHODOLOGY/PRINCIPAL FINDINGS: We determined bacterial species diversity in GCF samples of a group of periodontitis patients and delineated contributing bacterial and host-associated factors. Subgingival paper point (PP) samples from the same sites were taken for comparison. After DNA extraction, 16S rRNA genes were PCR amplified and DNA-DNA hybridization was performed using a microarray for over 300 bacterial species or groups. Altogether 133 species from 41 genera and 8 phyla were detected with 9 to 62 and 18 to 64 species in GCF and PP samples, respectively, per patient. Projection to latent structures by means of partial least squares (PLS) was applied to the multivariate data analysis. PLS regression analysis showed that species of genera including Campylobacter, Selenomonas, Porphyromonas, Catonella, Tannerella, Dialister, Peptostreptococcus, Streptococcus and Eubacterium had significant positive correlations and the number of teeth with low-grade attachment loss a significant negative correlation to species diversity in GCF samples. OPLS/O2PLS discriminant analysis revealed significant positive correlations to GCF sample group membership for species of genera Campylobacter, Leptotrichia, Prevotella, Dialister, Tannerella, Haemophilus, Fusobacterium, Eubacterium, and Actinomyces. CONCLUSIONS/SIGNIFICANCE: Among a variety of detected species those traditionally classified as Gram-negative anaerobes growing in mature subgingival biofilms were the main predictors for species diversity in GCF samples as well as responsible for distinguishing GCF samples from PP samples. GCF bacteria may provide new prospects for studying dynamic properties of subgingival biofilms

Epidemiology and Clinical Features of Peritonsillar Abscess: Is It Related to Seasonal Variations?

Objective:Peritonsillar abscess (PTA) is defined as pus accumulation between the tonsillar capsule and constrictor pharyngeal muscle. It can be seen as a complication of acute tonsillitis, but other mechanisms have also been proposed. In this study we aimed to reveal the seasonal variations and epidemiologic features of PTA.Methods:This is a retrospective, observational study. We reviewed 221 patients, and together with 24 recurrent cases, 245 admissions were reviewed in total. Age, gender, the duration of admission, seasonal and monthly distribution of cases, diabetes and smoking status, white blood cell count, and C-reactive protein (CRP) levels were recorded. Monthly and seasonal incidences of PTA were reviewed to see if there is any association of climate variations and PTA incidence rate. Features associated with the length of hospitalization and recurrence were also analyzed.Results:A total of 245 PTA cases were admitted to our clinic between June 2014 and June 2017. The highest amount of cases was observed in spring and winter. The C-reactive protein and white blood cell count (WBC) levels were found to be positively correlated with the length of hospitalization. There was no statistically significant correlation with recurrence and smoking, the WBC levels, CRP levels, and length of prior hospitalization. Diabetes status was not found to be associated with length of hospitalization and CRP levels.Conclusion:The present study reflects the epidemiologic and clinical features of PTA in İstanbul. Our findings showed that seasonal variation was not significant, consistent with previous studies. The highest incidence rate was observed in spring and winter. Length of hospitalization was found to be positively correlated with C-reactive protein and white blood cell count (WBC) levels. Recurrence was not statistically correlated with and smoking, the WBC levels, CRP levels, and length of hospitalization. More studies are recommended to reveal the different epidemiologic factors affecting the incidence of PTA

Stereological analysis of sciatic nerve in chickens following neonatal pinealectomy: an experimental study

<p>Abstract</p> <p>Background</p> <p>Although the injury to the peripheral nervous system is a common clinical problem, understanding of the role of melatonin in nerve degeneration and regeneration is incomplete.</p> <p>Methods</p> <p>The current study investigated the effects of neonatal pinealectomy on the sciatic nerve microarchitecture in the chicken. The chickens were divided into two equal groups: unpinealectomized controls and pinealectomized chickens. At the end of the study, biochemical examination of 10 sciatic nerve samples from both groups was performed and a quantitative stereological evaluation of 10 animals in each group was performed. The results were compared using Mann-Whitney test.</p> <p>Results</p> <p>In this study, the results of axon number and thickness of the myelin sheath of a nerve fiber in newly hatched pinealectomy group were higher than those in control group. Similarly, surgical pinealectomy group had significantly larger axonal cross-sectional area than the control group (p < 0.05). In addition, the average hydroxyproline content of the nerve tissue in neonatal pinealectomy group was higher than those found in control group. Our results suggest that melatonin may play a role on the morphologic features of the peripheral nerve tissue and that melatonin deficiency might be a pathophysiological mechanism in some degenerative diseases of peripheral nerves. The changes demonstrated by quantitative morphometric methods and biochemical analysis has been interpreted as a reflection of the effects of melatonin upon nerve tissue.</p> <p>Conclusion</p> <p>In the light of these results from present animal study, changes in sciatic nerve morphometry may be indicative of neuroprotective feature of melatonin, but this suggestion need to be validated in the human setting.</p