138 research outputs found

    Photocatalysis of organic effluents

    Get PDF
    PhD ThesisHeterogeneous photocatalytic oxidation is a relatively new technology for the destruction of toxic organic substances in water and so far has concentrated on reaction mechanisms and kinetics, but the engineering side was hardly touched. In this study a detailed investigation for suitable reactor design has been carried out using three different reactor types. An annular photoreactor was used with two different lamps with different intensities; low pressure and medium pressure mercury lamps. Two types of Ti02 powder catalysts Degussa P-25 and Tioxide PCi were used as slurry solutions and Degussa P-25 was found more photocatalytically active than the other. Two main organic reactants salicylic acid and 4-chlorophenol were studied to assess the light intensity effect. Although better reaction rates were achieved with the higher intensity medium pressure lamp, quantum yield results showed that low pressure lamp photons were utiised more effectively. The falling film reactor (FFR) was used to increase the light intensity utilisation with the stronger medium pressure lamp and using the same reactants in slurries catalysts Degussa P-25 gave superior results to those in annular reactor. Because of the thin film characteristics, FFR provided good oxygen transfer at the film/air interface. A commercial supported catalyst system as a fibre glass gauze was also used inside the reactor and was found as effective as slurry systems. In order to improve the thin film characteristics and combine these with an immobiised catalyst, a spinning disc reactor (SDR) with catalyst coated borosilicate disc was used to degrade aqueous solutions of 4- chlorophenol and salicylic acid. It was found that the efficiency of the photocatalyst process was dependent upon the type of UV source used. Lamps supplying shorter wavelength UV radiation were found to be more efficient than those whose emissions lay mainly in the near UV region. The method used to coat the disc of the SDR does not appear to meet its operational requirements.Istanbul Technical University. Higher Education Council of Turkey

    The ISIS Model and its Influence Over Global Terrorism

    Get PDF
    Counter-terrorism efforts against jihadist groups have been challenging for law enforcement and the military because terrorist organizations constantly update their tactics and mimic the successful strategies of popular and influential groups, such as ISIS, that have developed a specific model for carrying out their destructive acts. ISIS created its terrorism model in 2014 and has used it to control territory, spread its ideology, create provincial branches in different regions, inspire lone actors, and generate revenue. Terrorism databases are full of incidents that involve ISISstyle tactics, targets, and affiliated groups that act as provincial branches of ISIS. This paper examines how ISIS developed its model, what components that model involves, and how the model has influenced not only jihadist groups but also right-wing extremists and drug cartels around the world. The study uses a mixed method of quantative and qualitative research, and the proposed ISIS Model is developed through a rigorous literature review

    Yöresel Organik Ürünlerde Üretim ve Pazarlama Problemleri

    Get PDF
    Tarımsal ürün üretim sistemlerinde kimyasal girdi kullanılmadan, tamamen doğal girdilerle yapılan ürün yetiştiriciliği organik tarım olarak adlandırılmaktadır. Artan nüfusa paralel olarak ortaya çıkabilecek gıda açığına karşı tarımsal üretimi artırmaya yönelik çeşitli uygulamalar yapılmış ve önemli gelişmeler kaydedilmiştir. Sağlıklı beslenme ve çevre sağlığı açısından oldukça önemli bir uygulama olan organik tarım üretim modeli ülkemizin birçok kırsal kesiminde yerine getirilmesine rağmen tarımsal üretimle uğraşan kişiler bu önemli ürünlerden yeterince kazanç elde edememektedirler. Bu durumun en önemli sebepleri üreticilerin ürettikleri ürün konusunda yeterince bilgi sahibi olmamaları ile ilişkili olarak üretim, işleme ve paketleme yöntemlerinin ürün kalitesi ve sağlığına uygun bir şekilde düzenlenememesi ile pazarlama imkânlarından yeterince faydalanamama gibi durumlardır. Organik tarımsal üretim açısından önemli bir potansiyele sahip olan yöresel ürünlerin uygun yöntemlerle üretilip işlenerek daha sağlıklı şartlarda tüketicilere sunulmalarının sağlanması durumunda kırsal kesimdeki tarımsal ürün yetiştiricilerinin elde edecekleri gelirde artış sağlanabileceği gibi insan ve çevre sağlığına da önemli katkılar sağlanacaktır

    Comparison of Three Types of Continent Urinary Diversions in a Single Center

    Get PDF
    The results including the complication and continence rates for 3 types of continent urinary diversion were evaluated. From 1992 to 1998 we performed 58 continent urinary diversions after radical cystectomy for invasive transitional cell carcinoma (TCC) of the urinary bladder. All three types of continent diversions and ileal loop procedures were discussed and patient preferences were determined. The patient preference rate for continent urinary diversion was 96.6%, and half of these patients wanted to be completely dry. Mean age of the patients was 58.2 years. Of the 58 patients, 9 (15.5%) had a Kock pouch, 15 (25.8%) had a Kock neobladder and 34 (58.6%) had sigmoidorectal pouch (Mainz-II pouch). Early and late complication rates of the three different continent diversions were evaluated. The number of complications, such as urine leakage, pyelonephritis, hydronephrosis, reflux and stone formation, were similar in all three types of diversions. Two (5.9%) Mainz pouch II patients who had stopped oral alkalinization demonstrated severe hyperchloremic acidosis. Spontaneous pouch rupture occurred in 1 of the Kock pouches. Reoperation rates were higher with the Kock pouch and Kock neobladder cases. Daytime continence rates for the Kock pouch, Kock neobladder and Mainz II pouch were 77.7%, 86.7% and 100% respectively. Even though complete dryness may not be achieved in every patient, orthotopic bladder substitution appears to be the best choice after radical cystectomy. Although it carries the risk of life-long oral alkalinization therapy, the Mainz pouch II is associated with an excellent continence rate and may be a good alternative for patients who desire to be dry

    The pain symptoms and mass recurrence rates after ovarian cystectomy or uni/bilateral oophorectomy procedures in patients over 40 years old with endometriosis

    Get PDF
    Objectives: To evaluate the rates of pain and mass recurrence of the patients over 40 years old with endometriosis who underwent ovarian cystectomy or uni/bilateral oophorectomy. Material and methods: A retrospective study was conducted with 98 patients undergoing laparoscopic surgery for endometriosis in a tertiary referral center between the time period July 2015 and July 2019. All the patients followed every 3 months and requested to fill the Visual Analogue Scale (VAS) for evaluation of pelvic pain and an ultrasound scan was performed. The inclusion criteria for this study were as follows, patients with ages over 40, with regular menstrual periods, and who denied hysterectomy and any postoperative hormonal medical treatments. Results: When the groups were compared in terms of age, body mass index, cyst diameter, CA-125 serum concentrations, preoperative and after surgical pelvic pain scores, mean follow up periods, postoperative hospital stay. However, each of the mean numbers of gravidity and parity were significantly higher than bilateral salpingo-oophorectomy (BSO) groups compared to the other groups (p = 0.04 and p = 0.03, respectively). The laterality, the recurrence rates, and the type of recurrence did not have a significant effect in the group comparison. Conclusions: The ovarian tissue preserving procedures could be offered for the women over 40 years old suffering from endometriosis with no significant increase in pain symptom or mass recurrence rates considering beneficial effects of estrogen on cardiovascular system, vasomotor symptoms, and bone mineral density

    Enteric Duplication Cyst Located at the Posterior Tongue: A Rare Case Report and Review of the Literature

    Get PDF
    The lingual localization of an enteric duplication is extremely rare but may present with respiratory and feeding problems that require emergency intervention. A 7-month-old boy was brought to our clinic with feeding difficulties and tongue swelling. Physical examination showed a cystic lesion located near the left side of the tongue base that caused tongue protrusion to the contralateral side. During surgery, a 3-cm diameter opaque thick-walled cyst was found to be very closely adherent to the base of tongue, which was excised in its entirety. Following surgery, the patient fed during the early postoperative period and no complications were observed other than hypersalivation. On histological examination, a cystic lesion lined with intestinal mucosa and goblet cells was found. We present the rare case of a duplication cyst of the posterior tongue, with a literature review

    Clinical Study The Role of Serum Cytokines in the Pathogenesis of Hepatic Osteodystrophy in Male Cirrhotic Patients

    Get PDF
    Objective. In this study, we aimed to investigate the possible role of serum cytokines in the development of hepatic osteodystrophy. Matherial and Methods. 44 consecutive male cirrhotic patients (17 alcoholic, 20 hepatitis B, 7 hepatitis C), 15 age-and sex-matched chronic alcoholics without liver disease, and 17 age-and sex-matched healthy controls were included in the study during one year period. Bone mineral density was measured by dual X-ray absorptiometry in the lumbar vertebrate and femoral neck. Serum interleukin levels were measured by ELISA method. Results. Although osteopenia frequency between our cirrhotic patients was 20%, there was no difference in T-scores among the controls and other groups. Serum interleukin-1, interleukin-8, and tumor necrosis factor-alpha levels were not different between all groups. Serum interleukin-2 and interleukin-6 levels were higher in the cirrhotics than controls (P < 0.001). However, there were no significant difference between osteopenic and nonosteopenic cirrhotics. Conclusion. According to the results of the study in this small population of 44 male cirrhotic patients, frequency of hepatic osteopenia is small and serum interleukins 1, 2, 6, 8, and tumor necrosis factor-alpha may not play a role in the pathogenesis of hepatic osteodystrophy. Further studies in which large number of patients involved are necessary in this field

    CLP1 Founder Mutation Links tRNA Splicing and Maturation to Cerebellar Development and Neurodegeneration

    Get PDF
    SummaryNeurodegenerative diseases can occur so early as to affect neurodevelopment. From a cohort of more than 2,000 consanguineous families with childhood neurological disease, we identified a founder mutation in four independent pedigrees in cleavage and polyadenylation factor I subunit 1 (CLP1). CLP1 is a multifunctional kinase implicated in tRNA, mRNA, and siRNA maturation. Kinase activity of the CLP1 mutant protein was defective, and the tRNA endonuclease complex (TSEN) was destabilized, resulting in impaired pre-tRNA cleavage. Germline clp1 null zebrafish showed cerebellar neurodegeneration that was rescued by wild-type, but not mutant, human CLP1 expression. Patient-derived induced neurons displayed both depletion of mature tRNAs and accumulation of unspliced pre-tRNAs. Transfection of partially processed tRNA fragments into patient cells exacerbated an oxidative stress-induced reduction in cell survival. Our data link tRNA maturation to neuronal development and neurodegeneration through defective CLP1 function in humans

    Assessment of the requisites of microbiology based infectious disease training under the pressure of consultation needs

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Training of infectious disease (ID) specialists is structured on classical clinical microbiology training in Turkey and ID specialists work as clinical microbiologists at the same time. Hence, this study aimed to determine the clinical skills and knowledge required by clinical microbiologists.</p> <p>Methods</p> <p>A cross-sectional study was carried out between June 1, 2010 and September 15, 2010 in 32 ID departments in Turkey. Only patients hospitalized and followed up in the ID departments between January-June 2010 who required consultation with other disciplines were included.</p> <p>Results</p> <p>A total of 605 patients undergoing 1343 consultations were included, with pulmonology, neurology, cardiology, gastroenterology, nephrology, dermatology, haematology, and endocrinology being the most frequent consultation specialties. The consultation patterns were quite similar and were not affected by either the nature of infections or the critical clinical status of ID patients.</p> <p>Conclusions</p> <p>The results of our study show that certain internal medicine subdisciplines such as pulmonology, neurology and dermatology appear to be the principal clinical requisites in the training of ID specialists, rather than internal medicine as a whole.</p
    corecore