299 research outputs found

    Removal of silver (I) from aqueous solutions with clinoptilolite

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    The aim of the present work was to investigate the ability of natural zeolite, clinoptilolite, to remove silver ions from aqueous solution. Towards this aim, batch adsorption experiments were carried out and the eect of various parameters on this removal process has been investigated. The eects of pH, adsorption time, metal ion concentration and the acidic treatment on the adsorption process were examined. The optimum pH for adsorption was found to be 4.0. It was found that acid treatment has a substantial eect on the metal uptake. In adsorption studies, residual Ag+ concentration reached equilibrium in a short duration of 45 min. Maximum adsorption capacity, 33.23 mg Ag+/g zeolite, showed that this adsorbent was suitable for silver removal from aqueous media. Adsorption phenomena appeared to follow Langmuir and Freundlich isotherms

    Fuzzy controller design for parametric controllers

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    Ankara : Department of Electrical and Electronics Engineering and Institute of Engineering and Sciences, Bilkent University, 1996.Thesis (Master's) -- Bilkent University, 1996.Includes bibliographical references leaves 53-54In this thesis, fuzzy logic controller (FLC) design for tuning some parametric controller is investigated. The objective in designing an FLC is to determine the rule bcise of the system and the data base which includes membership functions, set operations, and inference engine. Two designs have been realized using heuristic rule generation; one for a PID controller and one for a lead-lag type controller. The FTCs in these designs set the parcimeters of the PID and leadlag controller on-line. The rules and the corresponding membership functions are constructed by observing the effect of the changes of the parameters on the overall performance. One other design is performed using the desired inputoutput data pairs. In this design Fuzzy c-Means clustering algorithm is used to e.xtract the rules and the membership functions from the input-output data of the system. Simulation results showed that better controller performance can be cichieved by FLCs in comparison with the classical design methods.Akgül, MuratM.S

    A new species of marrubium (Lamiaceae) from central Anatolia, Turkey

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    Marrubium sivasense Aytaç, Akgül & Ekici sp. nova (Lamiaceae) is described and illustrated from Central Anatolia, Turkey. Th e new species most resembles Marrubium depauperatum, but it diff ers by 3-10 fl owered verticillasters, crenate to crenulated leaf margins, and unequal calyx teeth. Th e ecology and phenology of the new species as well as its etymology, conservation status, and diagnostic features are discussed

    Evaluation of enamel pearls by cone-beam computed tomography (CBCT)

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    Objective: The aim of this study was to evaluate the frequency of enamel pearls according to population, sex and tooth groups on Cone-Beam Computed Tomography (CBCT) or Dental Volumetric Tomography (DVT) scans of patients, retrospectively. Study Design: In this study, 15185 teeth belonging to 768 patients, 430 female and 338 male, was performed cross-sectional examination by CBCT. The volumetric Computed Tomography used in the study is Newton FP based on flat-panel. The data were analyzed with Pearson chi-squared test. Results: Enamel pearls were detected in 36 subjects (4.69%). Of these enamel pearls, 19 were detected in male and 17 were in male. There was no statistically a significant association between prevalence of enamel pearls and sex. All of enamel pearls were detected in molar teeth, for prevalence 0.83%. Conclusion: All of enamel pearls are found upper and lower molar teeth, especially the most commonly in maxillary second and third molars. © Medicina Oral S. L

    Yüksek Dereceli Kasa İnvaze Olmayan Mesane Tümörlerinde Histolojik Derecelendirme Oranının Progresyona Etkisi

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    Aim: Histopathological classification is one of the main prognostic factors for non-muscle invasive bladder tumors (NMIBT). Weevaluated the relationship between tumor progression and the ratio of high-grade differentiation plus other routine pathologicalparameters in NMIBT.Materials and Methods: Ninety-two patients diagnosed with high grade NIMBT were analyzed between 2010-2018. Demographicinformation, tumor size, localization, multicentricity, and recurrence/progression situation were evaluated retrospectively. The high/lowgrade percentage ratio of tumor cells, tumor stage, differentiation, necrosis, lamina-propria invasion, lymphovascular invasion, andcarcinoma in-situ presence were also examined by two uro-pathologist. The effect on tumor progression was evaluated with pathologicalfindings.Results: Seventy-four (80.4%) of the patients were reported as T1 and 18 (19.6%) as Ta. The mean ratio of high-grade findings was11.9±8.5% and 69.5±28.1% for Ta and T1 patients, respectively(p25%, >50% and >75% was found to be 67(72.8%),54(58.7%) and 43(46.7%), respectively. The high-grade ratio for >25% was in only 1 Ta patient while it was in 66 of the T1patients(p75%(p50%(p=0.025).Conclusion: When evaluating the nuclear grade, defining tumors solely as high-grade leads to stratifying a highly heterogeneouspopulation in a single group. Higher rate of progression is observed in NIMBT patients with high-grade ratio >50%.KİOMT’de yüksek dereceli hücresel farklılaşma oranı ve diğer rutin patolojik parametrelerin progresyona etkisi değerlendirildi. Materyal ve Metot: Çalışmaya 2010-2018 yılları arasında transüretral mesane rezeksiyonu sonrası yüksek dereceli KİOMT tanısı alan 92 hasta dahil edildi. Hastaların demografik bilgileri, tümör çapı, lokalizasyonu, multisantrisitesi ve nüks/progresyon varlığı-süresi retrospektif olarak değerlendirildi. Ayrıca tümör hücrelerinin yüksek derece/düşük derece yüzdesi, tümör evresi, diferansiyasyon, nekroz, lamina propria invazyonu, lenfovasküler invazyon ve karsinoma in-situ varlığı iki üro-patolog tarafından incelendi. Elde edilen bulguların tümör progresyonu üzerine etkisi araştırıldı. Bulgular: Hastaların 74’ü(%80,4) T1, 18’i(%19,6) Ta olarak rapor edildi. Ta tanılı hastalarda yüksek derece oranı %11,9±8,5 iken, T1’lerde %69,5±28,1 olarak tespit edildi (p%25,>%50 ve>%75 olan hasta sayısının sırasıyla 67(%72,8), 54(%58,7) ve 43(%46,7) olduğu görüldü. Ta olan hastaların sadece 1’inde yüksek derece oranı>%25 olarak gözlenirken, T1 hastalarının 66’sında yüksek derece oranının>%25 olduğu belirlendi (p%75 olduğu görüldü. T1 yüksek derece oranları>%50 olan hastalarda progresyon, patolojik evresi T1 yüksek derece oranları %50 olan hastalarda progresyon anlamlı derecede artmaktadır

    Urodynamic findings of multiple sclerosis patients at a single institution

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    Aim: Multiple sclerosis (MS) is a chronic and progressive disease of the central nervous system (CNS). The destructive effect of MS on the urogenital system has been demonstrated in many studies especially in young adults. Urodynamic evaluation is recommended in the diagnosis of urogenital system pathologies for MS patients. Unfortunately, there are not enough studies evaluating the urodynamic examinations of MS patients in our country. In this study, urodynamic findings of patients with MS were evaluated. Material and Method: A total of 58 patients (39 female and 19 male) were included in the study. The urodynamic findings of the patients in the same center between January 2011 and October 2017 were evaluated retrospectively. Urodynamic evaluation was performed with 20 ml of infusion per minute according to the International Continence Society standards. Results: The mean age of the patients was 47.4 +/- 8.8 years. The mean duration of multiple sclerosis was 11.8 +/- 7.4 years. When the features of multiple sclerosis were evaluated, 13 (22.4%) patients had a progressive type, 20 (34.5%) had a secondary progressive type, and 25 (43.1%) had relapsing-remitting (with relapses and remissions). The urodynamic findings of the patients are shown in Table 1. Urodynamic evaluations of patients with urinary incontinence are reported as 'Urge type urinary incontinence' was observed in 30 (83.3%), 'stress type urinary incontinence' in 5 (13.9%) and 'mixed type urinary incontinence' in 1 (2.8%) patient. Discussion: Multiple sclerosis is a common neurological pathology which has different urinary system findings. Detrusor overactivity is the most common urinary manifestation, and patients may also have impaired contractility, detrusor sphincter dyssynergia, urodynamic stress incontinence, and bladder outlet obstruction

    The delay in the diagnosis and treatment of newly diagnosed bladder cancer patients during COVID 19 pandemic

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    Background: To evaluate the newly diagnosed bladder cancer(BC) patients during the pandemic period and compare them with the corresponding last4 years. Objectives: To document the time schedules of BC patient evaluation and define the possible delays and investigate the reasons. Methods: Newly diagnosed BC patients who underwent transurethral resection of bladder tumour in the last5 years were retrospectively included to study.The patients were divided into 5 groups.Group-1 was composed of patients diagnosed be-tweenMarch,1,2016-March-1,2017. The patients who were diagnosed in the further corresponding years formed group 2,3 and 4. The last group(Group-5) was composed of patients who were diagnosed during the pandemic period which was between March,1,2020 and March,1,2021. The clinicodemographic properties and diagnostic time schedules of the patients were com-pared between the groups. Results: There were56 patients in Group-1,60 patients in Group-2,61 patients in Group-3,68 patients in Group-4,and58 pa-tients inGroup-5. The mean hospital admission period was102.5 +/- 179.0days during the pandemic period which ranged be-tween24.5 +/- 32.0 and38.3 +/- 69.1days before thepandemic.(p=0.002)The diagnosis-anesthesia period was significantly higher during the pandemic pandemic period.(p=0.034) Conclusions: The pandemic period has caused some delays in the diagnosis and treatment of BC patients. Telemonitoring systems may be useful to prevent the possible diagnostic and treatment delays for newly diagnosed BC patients

    Morphometric and morphologic evaluation of the mental foramen in relation to age and sex: an anatomic cone beam computed tomography study

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    Objective: The aim of this study was to assess the vertical and horizontal position, angle, and diameter of the mental foramen (MF) according to sex and age by cone beam computed tomography in a Turkish patient population. Methods: Cone beam computed tomography records of 192 consecutive patients consisting of 106 women and 86 men were examined, retrospectively. The vertical and horizontal positions of MF, angle and diameter of MF, and distance from MF to the alveolar crest and the base of the mandible were evaluated with respect to sex and age groups. Results: There were statistically significant differences in the distance of MF to the alveolar crest according to age groups. When we compared the right and left sides, we have only found out statistically significant differences in the angles of MF and that it was higher in the left side. Conclusions: From our results, the detection of the position of MF can provide detailed information for preoperative treatment planning (for surgery and dental implant surgery procedures), especially in the mandibular premolar region

    Multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study

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    Objective: To evaluate the effect of ureteral access sheath (UAS) use and calibration change on stone-free rate and complications of retrograde intrarenal surgery (RIRS). Methods: Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively included. Firstly, patients were compared after 1:1 propensity score matching, according to UAS usage during RIRS (UAS used [+] 87 and UAS non-used [?] 87 patients). Then all UAS+ patients (n=481) were subdivided according to UAS calibration: 9.5–11.5 Fr, 10–12 Fr, 11–13 Fr, and 13–15 Fr. Primary outcomes of the study were the success and complications of RIRS. Results: Stone-free rate of UAS+ patients (86.2%) was significantly higher than UAS? patients (70.1%) after propensity score matching (p=0.01). Stone-free rate increased with higher caliber UAS (9.5–11.5 Fr: 66.7%; 10–12 Fr: 87.3%; 11–13 Fr: 91.3%; 13–15 Fr: 100%; p<0.0001). Postoperative complications of UAS+ patients (11.5%) were significantly lower than UAS? patients (27.6%) (p=0.01). Complications (8.7%) with 9.5–11.5 Fr UAS was lower than thicker UAS (17.3%) but was not statistically significant (p=0.08). UAS usage was an independent factor predicting stone-free status or peri- and post-operative complications (odds ratio [OR] 3.654, 95% confidence interval [CI] 1.314–10.162; OR 4.443, 95% CI 1.350–14.552; OR 4.107, 95% CI 1.366–12.344, respectively). Conclusion: Use of UAS in RIRS may increase stone-free rates, which also increase with higher caliber UAS. UAS usage may reduce complications; however, complications seemingly increase with higher UAS calibration. © 2022 Editorial Office of Asian Journal of Urolog

    EVALUATION OF THE ASSOCIATION OF PIGMENTARY MACULOPATHY IN PRIMARY BLADDER PAIN SYNDROME PATIENTS RECEIVING PENTOSAN POLYSULFATE SODIUM TREATMENT

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    Objective Primary bladder pain syndrome (PBPS) is characterized with suprapubic pain accompanied by at least one lower urinary tract symptoms including frequent urination, urinary urgency and nocturia for more than 6 weeks. While there are many alternative therapies for the treatment of PBPS, the only approved oral medication is PPS (pentosan polysulfate sodium). As it has been associated with retinal toxicity after its widespread use, this study aims to evaluate the relationship between PPS use and maculopathy. Material and Methods The patients diagnosed with PBPS between 2010 and 2020 who may only benefit from PPS use were included into the study after subgroup and phenotype assessment (urinary and non-ulcerative organspecific subgroups). In our study, patients who had history of degenerative maculopathy or diseases predisposing to maculopathy (age-related macular degeneration, diabetes mellitus, hypertension, chronic vascular disorders, central serous chorioretinopathy, retinal dystrophy, epiretinal membrane, and chronic exposure to hydroxychloroquine) were excluded to prevent possible misdirection. Patients underwent best-corrected visual acuity assessment using Snellen chart, anterior segment and fundus examination using slit lamp biomicroscopy, and intraocular pressure measurement. Color vision test (Ishihara test), posterior segment optical coherence examination and 10-2 visual field test were performed, and color images of the fundus and autofluorescence imaging were obtained. Best-corrected visual acuity, color vision results, macular, choroidal and mean retinal nerve fiber thicknesses, mean deviation of the visual field and fundus findings were recorded. Results Out of 15 patients included into the study, 4 (37.5%) were male and 11 (73.3%) were female. The mean age of the patients was 53.3±11.2 years. During the follow-up, the duration of oral PPS use was found to be 33.01±10.59 months, cumulative oral PPS dose to be 216.02±97.63 g and duration of diagnosis to be 66.64±39.37 months. The mean central macular thickness of the patients was measured to be 254.55±33.11 ?m, and the mean choroidal thickness to be 261.82±34.22 ?m. Mean deviation of the visual field of the patients was found to be -1.89 ±-1.25 dB. The mean retinal nerve fiber thickness was measured to be 98.1±17.62 ?m from the fundus autofluorescence images of the patients. Furthermore, in the present study, the ocular findings of the patients who are at below and above the mean cumulative dose and exposure period were compared. Conclusion This study detected no correlation between longterm PPS use and maculopathy. When forming the patient group; it is crucial to exclude patients with comorbidities such as diabetes mellitus and hypertension, and to form a homogeneous group by phenotype and subgroup assessment. Randomized, prospective, multi-center studies are needed to better assess this correlation
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