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Item A Local Search Heuristic with Self-tuning Parameter for Permutation Flow-Shop Scheduling Problem(2009) Dengiz, Berna; Alabas-Uslu, Cigdem; Sabuncuoglu, IhsanIn this paper, a new local search metaheuristic is proposed for the permutation flow-shop scheduling problem. In general, metaheuristics are widely used to solve this problem due to its NP-completeness. Although these heuristics are quite effective to solve the problem, they suffer from the need to optimize parameters. The proposed heuristic, named STLS, has a single self-tuning parameter which is calculated and updated dynamically based on both the response surface information of the problem field and the performance measure of the method throughout the search process. Especially, application simplicity of the algorithm is attractive for the users. Results of the experimental study show that STLS generates high quality solutions and outperforms the basic tabu search, simulated annealing, and record-to-record travel algorithms which are well-known local search based metaheuristics.Item The Effect of Haematological Parameters on Overall Survival in Advanced Stage Non Small Cell Lung Cancer(2014) Oguz, Arzu; Colak, Dilsen; Ersoy, Ugur; Imamoglu, Inanc G.; Altinbas, Mustafa; Unal, Dilek; Zararsiz, GokmenIn this study, we aimed to evaluate the prognostic value of pretreatment blood count values, particularly WBC counts, in patients with advanced non-small cell lung cancer (NSCLC). The records of 186 patients with advanced stage (stage IIIB and IV) NSCLC were assessed retrospectively. Patients were divided into 3 subgroups according to WBC levels; <= 0000 /mm(3) as Group 1, >10000 and <= 15000/mm(3) as Group 2 and >15000/mm(3) as Group 3. Patient and tumor characteristics as well as outcomes in terms of overall survival (OS) were evaluated. Median OS was 13.3 months in the whole population, 25.7 months in stage IIIB and 8.9 months in stage IV patients. According to the pretreatment leukocyte values, median OS was 17.9 months in Group 1, 11.2 months in Group 2 and 8.4 months in Group 3 (p= 0.003). Median OS values in WBC groups according to stages IIIB and IV were significantly different (p< 0.001). In multivariate analyses, ECOG-PS 2 or 3, stage IV disease, anemia and high WBC levels were associated with poorer OS. In this study, higher pretreatment WBC levels were associated with poorer OS in patients with advanced stage NSCLC. Pretreatment WBC counts may represent a simple prognostic factor and may aid in tailoring treatment in patients with advanced NSCLC.Item The Prevalence, Etiologic Agents and Risk Factors for Urinary Tract Infection Among Spinal Cord Injury Patients(2014) Togan, Turhan; Azap, Ozlem Kurt; Durukan, Elif; Arslan, HandeBackground: Urinary tract infections (UTIs) are important causes of morbidity and mortality in patients with spinal cord injury and 22% of patients with acute spinal cord injury develop UTI during the first 50 days. Objectives: The aim of this study was to determine the prevalence, etiologic agents and risk factors for asymptomatic bacteriuria and symptomatic urinary tract infections in patients with spinal cord injury. Patients and Methods: This was a prospective investigation of spinal cord injury patients with asymptomatic bacteriuria and symptomatic urinary tract infections in Baskent University Medical Faculty Ayas Rehabilitation Center and Ankara Physical Therapy and Rehabilitation Center between January 2008 and December 2010. The demographic status, clinical and laboratory findings of 93 patients with spinal cord injury were analyzed in order to determine the risk factors for asymptomatic or symptomatic bacteriuria Results: Sixty three (67.7%) of 93 patients had asymptomatic bacteriuria and 21 (22.6%) had symptomatic urinary tract infection. Assessment of the frequency of urinary bladder emptying methods revealed that 57 (61.3%) of 93 patients employed permanent catheters and 24 (25.8%) employed clean intermittent catheterization. One hundred and thirty-five (48.0%) of 281 strains isolated form asymptomatic bacteriuria attacks and 16 (66.6%) of 24 strains isolated from symptomatic urinary tract infection attacks, totaling 151 strains, had multidrug resistance (P > 0.05). One hundred (70.4%) of 142 Escherichia coli strains and 19 (34.5%) of 55 Klebsiella spp strains proliferated in patients with asymptomatic bacteriuria; 8 (80%) of 10 E. coli strains and 4 (80%) of 5 Klebsiella spp. strains were multidrug resistant. Conclusions: The most common infectious episode among spinal cord injury patients was found to be urinary tract infection. E. coli was the most common microorganism isolated from urine samples. Antibiotic use in the previous 2 weeks or 3 months, hospitalization during the last one-year and previous diagnosis of urinary tract infection were the risk factors identified for the development of infections with multi-drug resistant isolates. Urinary catheterization was found to be the only independent risk factor contributing to symptomatic urinary tract infection.Item Primary Extranodal Non-Hodgkin's Lymphoma: Clinicopathological Features, Survival and Treatment Outcome in Two Cancer Centers of Southern Turkey(2014) Mertsoylu, Huseyin; Muallaoglu, Sadik; Besen, Ayberk Ali; Erdogdu, Suleyman; Sezer, Ahmet; Sedef, Ali Murat; Kose, Fatih; Arican, Ali; Ozyilkan, OzgurBackground: The aim of this study was to assess the epidemiological and clinicopathological characteristics of primary extranodal non-Hodgkin's lymphoma (pENL) patients, focusing on treatment and survival outcome. Materials and Methods: Between October 2003 and March 2012, 802 patients with non-Hodgkin's lymphoma (NHL) were diagnosed and treated in two different cancer centers of Southern Turkey. Results: pENL, constituted 12.4% (100/802) of all NHL studied during this period. Median age of the patients was 56 years (range 17-87 years) and the male: female distribution was 3:2. Eighty-five of 100 patients (85%) were in stage I/II, 9/100 (9%) in stage III, whereas 6/100 (6%) were in stage IV. Head and neck constituted the most common site (51/100, 51%), followed by gastrointestinal tract (GIL) (37/100, 37%), and cerebrum (CL) (5/100, 5%). Diffuse large B cell lymphoma (DLBCL) was the most common histological type, observed in 53% of patients, followed by marginal zone extranodal lymphoma (13%). Most of patients (76%) received a CHOP containing regimen. Complete remission (CR) were achieved in 71% of patients. The median follow-up duration of all patients was reported as 37.6 months (range, 0.8-165 months). This period was reported as 137.5 months (range, 117.5-1578.6 months) in gastrointestinal lymphoma (GIL) patients, 119.0 months (range, 91.8-146.1 months) in head and neck lymphoma (HNL) patients, and 18.4 months (range, 12.6-24.1 months) in cerebral lymphoma (CL) patients. Conclusions: Head and neck, and the gastrointestinal tract were the two most common extranodal sites observed. Histologically DLBC accounted for the majority of cases. Most patients were on earlier stages, had low-low intermediate IPI scores and had a favorable prognosis.Item Ulnar Nerve Conduction Abnormalities in Turkish Taxi Drivers(2014) Afsar, Sevgi Ikbali; Cetin, Nuri; Ayas, Sehri; Mumcu, Gamze Akin; Karatas, MetinObjectives: This study aims to investigate the presence of ulnar entrapment neuropathy at the elbow in taxi drivers, and possible relationship between ulnar entrapment neuropathy and habitually leaning the left elbow on the lower edge of the window. Patients and methods: The study was performed between December 2008 and February 2009 in Ankara and included 40 male taxi drivers (mean age 35.5 +/- 7.3 years; range 25 to 54 years) and 40 healthy male controls (mean age 33.6 +/- 6.1 years; range 25 to 54 years). Nerve conduction studies were performed on both upper limbs of all participants. Results: Left side motor and sensory nerve conduction velocities at the elbow segment of the ulnar nerve were significantly decreased, while F latency of the ulnar nerve was significantly prolonged in taxi drivers. Motor and sensory conduction velocity over both left and right ulnar nerve at the elbow segment were significantly decreased, while F latency of the ulnar nerve was significantly prolonged in the taxi drivers compared to the control group. Ulnar nerve conduction parameters and F latency on both sides were statistically similar in the non-leaning group of taxi drivers; however, motor and sensory conduction studies over the left side of the ulnar nerve elbow segment were slower and F latency was longer in the leaning group of taxi drivers, compared to the right side and to the non-leaning group of taxi drivers. Conclusion: Prolonged elbow flexion and habitually leaning the left elbow may cause electrodiagnostically diagnosed ulnar entrapment neuropathy in taxi drivers.Item Explaining intrapreneurial behaviors of employees with perceived organizational climate and testing the mediating role of organizational identification: A research study among employees of Turkish innovative firms(2014) Tastan, Secil Bal; Gucel, CemThis study examines perceived organizational climate and organizational identification as potential antecedents of employees' intrepreneurial behaviors. In particular, the study suggests positive relationships between perceived organizational climate components-structural support and recognition-and intrepreneurial behaviors construct. In addition, employees' organizational identification is suggested to have a mediating role on the relationship between organizational climate and intrepreneurial behaviors. The survey of this study is performed among employees working in high performing and innovative firms operating in White Good Manufacturing, Food and Drink, Telecommunication, and Textile industries in Turkey. The obtained data from the questionnaires are analyzed through the SPSS statistical packaged software. Analyses results revealed that both dimensions of organizational climate (structural support and organizational recognition) significantly and positively related to intrepreneurial behaviors and perceived organizational identification mediate the effects of the organizational climate on the intrepreneurial behaviors construct. (C) 2014 The Authors. Published by Elsevier Ltd.Item Visual outcome of intravitreal ranibizumab for exudative age-related macular degeneration: timing and prognosis(2014) Canan, Handan; Sizmaz, Selcuk; Altan-Yaycioglu, Rana; Sariturk, Cagla; Yilmaz, GurselPurpose: To describe 1-year clinical results of intravitreal ranibizumab treatment in patients with choroidal neovascularization secondary to exudative age-related macular degeneration (AMD) and to evaluate whether early treatment is a predictive value for prognosis of the disease. Materials and methods: Clinical records were retrospectively reviewed of 104 eyes that underwent intravitreal ranibizumab therapy for exudative AMD. Patients were divided into two groups according to their symptom duration: group 1,,1 month; and group 2, 1-3 months. After three monthly injections, patients were examined monthly, and subsequent injections were performed as needed. Results: There were 43 female (48.9%) and 45 males (51.1%). The follow-up time was 13.7 +/- 1.9 (12-19) months. The mean logarithm of minimum angle of resolution best-corrected visual acuity (BCVA) improved significantly, from 0.45 +/- 0.639 at baseline to 0.08 +/- 0.267 at 12 months in group 1, and from 1.06 +/- 0.687 at baseline to 0.75 +/- 0.563 at 12 months in group 2. The increase in BCVA was statistically significant in group 1 (P=0.009). The mean central retinal thickness (CRT) decreased significantly, from 355.13 +/- 119.93 mu m at baseline to 250.85 +/- 45.48 mu m at 12 months in group 1, and from 371.88 +/- 91.047 mu m at baseline to 268.61 +/- 53.51 mu m at 12 months in group 2. The decrease in CRT was statistically significant in group 1 (P=0.001). Conclusion: Intravitreal ranibizumab therapy was effective in significantly increasing mean BVCA and reducing CRT. Shorter duration of AMD, as measured by the subjective duration of visual symptoms, is associated with better visual outcome after treatment.Item Depigmented skin and phantom color measurements for realistic prostheses(2014) Tanner, Paul; Leachman, Sancy; Boucher, Kenneth; Ozcelik, Tuncer BurakPurposeThe purpose of this study was to test the hypothesis that regardless of human skin phototype, areas of depigmented skin, as seen in vitiligo, are optically indistinguishable among skin phototypes. The average of the depigmented skin measurements can be used to develop the base color of realistic prostheses. Methods and MaterialsData was analyzed from 20 of 32 recruited vitiligo study participants. Diffuse reflectance spectroscopy measurements were made from depigmented skin and adjacent pigmented skin, then compared with 66 pigmented polydimethylsiloxane phantoms to determine pigment concentrations in turbid media for making realistic facial prostheses. ResultsThe Area Under spectral intensity Curve (AUC) was calculated for average spectroscopy measurements of pigmented sites in relation to skin phototype (P=0.0505) and depigmented skin in relation to skin phototype (P=0.59). No significant relationship exists between skin phototypes and depigmented skin spectroscopy measurements. The average of the depigmented skin measurements (AUC 19,129) was the closest match to phantom 6.4 (AUC 19,162). ConclusionAreas of depigmented skin are visibly indistinguishable per skin phototype, yet spectrometry shows that depigmented skin measurements varied and were unrelated to skin phototype. Possible sources of optical variation of depigmented skin include age, body site, blood flow, quantity/quality of collagen, and other chromophores. The average of all depigmented skin measurements can be used to derive the pigment composition and concentration for realistic facial prostheses.Item The generalized Baskakov type operators(2014) Serenbay, Sevilay Kirci; Atakut, Cigdem; Buyukyazici, IbrahimThe use of Baskakov type operators is difficult for numerical calculation because these operators include infinite series. Do the operators expressed as a finite sum provide the approximation properties? Furthermore, are they appropriate for numerical calculation? In this paper, in connection with these questions, we define a new family of linear positive operators including finite sum by using the Baskakov type operators. We also give some numerical results in order to compare Baskakov type operators with this new defined operator. (C) 2013 Elsevier B.V. All rights reserved.Item Dental Anxiety and Fear: Relationship with Oral Health Behavior in a Turkish Population(2014) Yozugullu, Bulem; Gulsahi, Ayse; Celik, Cigdem; Bulut, SuleThe aim of this study was to assess fear and anxiety in dental patients. Five hundred patients were evaluated using the Modified Dental Anxiety Scale and the Dental Fear Scale, along with a questionnaire. Oral health status was assessed using the Decayed, Missing, and Filled Teeth (DMFT)/Decayed, Missing, and Filled Surfaces (DMFS) index. Statistic al analysis was performed (P <.05). Sex significantly affected dental anxiety (P <.05), and sex, marital status, having children, and time elapsed since last visit to clinician affected dental fear (P <.05). DMFT/DMFS scores were not related to dental anxiety or fear (P >.05). Female sex alone was a significant predictor of dental anxiety; female sex, adulthood, marriage, having children, and time passed since last visit to a clinician are significant predictors of fear.