Bilateral Double-headed Recurrent Pterygium: A Case Presentation and Literature Review

Pterygium is a frequent corneal disease characterized by growing of fibrovascular tissue from the bulbar conjunctiva onto the cornea. Although the causes of pterygium are not obvious, sun exposure is closely correlated with its development. Pterygium, especially double-headed pterygium is mostly seen in warm climate and in individuals who work outdoors. A minority of pterygium is double-headed (both temporal and nasal origins). Bilateral recurrent double-headed pterygium is a very rare condition. Here, we reported a 35-year-old male patient with bilateral recurrent double-headed pterygium. A brief review about the recent literature concerning the etiology, associated risk factors, operation types and management of patients with recurrent pterygium was also discussed. The patient was a field worker, smoker and had a family history of pterygium. There was no ocular surgery history except pterygium surgery 15 years ago in both eyes. A successful pterygium excision was performed under local anesthesia with the vertical split conjunctival autograft transplantation (CAT) in both temporal and nasal parts of the right eye (randomly) for cosmetic disfigurement and avoidance of recurrence. The pathological report was consistent with pterygium. At postoperative first week, first and 1.5th month visits, conjunctival autografts were in place and stable. No complications such as infection, corneal thinning or graft dislocation were seen. The patient was satisfied with his right eye and demanded the same surgery for his left eye. We suggest vertical split simultaneous CAT as a safe and useful surgical method for the treatment of recurrent double-headed pterygium; however, longer follow-up is required to confirm the outcome

Can the mean platelet volume be a predictor of disease activity in primary Sjogren syndrome?

Background: Disease activity in primary Sjogren syndrome (PSS) is measured by the EULAR Sjogren’s syndrome disease activity index (ESSDAI) and patient reported index (ESSPRI). Studies investigating the association between ESSDAI and ESSPRI and previously reported indicators of systemic inflammation are few in the literature. The aim of this study was to determine the clinical utility of the mean platelet volume (MPV) in predicting disease activity in PSS patients.Methods: A total of 190 subjects including ninety-five PSS patients and ninety-five healthy controls were enrolled. Associations between MPV and other known indicators of systemic inflammation (red cell distribution width (RDW), neutrophil to lymphocyte ratio (NLR) and patient clinical characteristic, ESSDAI and ESSPRI were investigated by using spearman correlation and linear regression analysis.Results: MPV levels were found to be significantly higher in the PSS group than the control group (10.5±1.2 versus 9.0±1; P<0.001 respectively). Correlation and regression analysis showed a positive correlation between MPV levels and ESSDAI scores (r=0.24, p=0.01). There was a negative correlation between ESSPRI and MPV levels (r=-0.32, p=0.001). NLR and RDW did not show any significant correlation with either ESSDAI or ESSPRI scores.Conclusions: MPV levels are significantly elevated in PSS patients compared to their control peers, positively correlate with ESSDAI but negatively with ESSPRI scores. MPV might be a useful inflammatory marker to measure disease activity in PSS.

Bacteremia due to Acinetobacter ursingii in infants: Reports of two cases

Acinetobacter ursingii is an aerobic, gram-negative, opportunistic microorganism which is rarely isolated among Acinetobacter species. We present two immunocompetent infants who developed bacteremia due to A.ursingii. The first patient is a two -month- old boy who had been hospitalized in pediatric surgery unit for suspected tracheo-esophageal fistula because of recurrent aspiration pneumonia unresponsive to antibiotic therapy. The second patient is a fourteen -month- old boy with prolonged vomiting and diarrhea. A. ursingii was isolated from their blood cultures. They were successfully treated with ampicillin-sulbactam. Although A.ursingii has recently been isolated from a clinical specimen; reports of infection with A.ursingii in children are rare. A.ursingii should be kept in mind as an opportunistic microorganism in children.Pan African Medical Journal 2016; 2

Octagonal Shaped Metamaterial Absorber Based Energy Harvester

In this study, a novel octagonal shaped metamaterial based broadband absorber is proposed for energy harvesting at WIMAX wireless communication band. The proposal has an absorption of 99.97 % at 5.5 GHz with a bandwidth of 1 GHz between 5 GHz and 6 GHz in Transverse Electric (TE) mode. Transverse Electric (TE), Transverse Magnetic (TM) and Transverse Electromagnetic (TEM) modes are studied numerically in this paper. In TM and TEM modes, proposed structure has absorption of nearly 96 % and 98 % respectively at 6 GHz. The proposed structure is polarization angle independent which is important for energy harvesting applications. Energy harvesting application is realized by using resistive loads on the design, simulations are parametrically studied on resistive loads and experimental study is realized for reflection coefficient measurement and compared with simulated results. Both experimental and simulated results are complying with each other. The proposed structure has different usage areas in stealth areas, detection and imaging. DOI: http://dx.doi.org/10.5755/j01.ms.24.3.18625</p

Analysis of the common genetic component of large-vessel vasculitides through a meta- Immunochip strategy

Giant cell arteritis (GCA) and Takayasu's arteritis (TAK) are major forms of large-vessel vasculitis (LVV) that share clinical features. To evaluate their genetic similarities, we analysed Immunochip genotyping data from 1,434 LVV patients and 3,814 unaffected controls. Genetic pleiotropy was also estimated. The HLA region harboured the main disease-specific associations. GCA was mostly associated with class II genes (HLA-DRB1/HLA-DQA1) whereas TAK was mostly associated with class I genes (HLA-B/MICA). Both the statistical significance and effect size of the HLA signals were considerably reduced in the cross-disease meta-analysis in comparison with the analysis of GCA and TAK separately. Consequently, no significant genetic correlation between these two diseases was observed when HLA variants were tested. Outside the HLA region, only one polymorphism located nearby the IL12B gene surpassed the study-wide significance threshold in the meta-analysis of the discovery datasets (rs755374, P?=?7.54E-07; ORGCA?=?1.19, ORTAK?=?1.50). This marker was confirmed as novel GCA risk factor using four additional cohorts (PGCA?=?5.52E-04, ORGCA?=?1.16). Taken together, our results provide evidence of strong genetic differences between GCA and TAK in the HLA. Outside this region, common susceptibility factors were suggested, especially within the IL12B locus

Amerika Birleşik Devletleri’ndeki afet yönetimi İle Türkiye’deki afet yönetiminin karşılaştırılması

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Bu tezin amacı, Türkiye'deki afet yönetiminden sorumlu kurum olan Başbakanlık Afet ve Acil Durum Başkanlığı (AFAD) ile Amerika Birleşik Devletlerindeki afet yönetiminden sorumlu kurum olan Federal Emergnecy Management'in (FEMA) karşılaştırılmasıdır. Bu karşılaştırmayı yapabilmek için AFAD ve FEMA'nın kurulmasından bu günümüze kadar gelen süreçte her iki ülkenin afet yönetiminin anlaşılması ve açıklanması gerekmektedir. Bu doğrultuda üç temel varsayım geliştirilmiştir. İlk olarak, Türkiye'deki afet yönetim sisteminin karmaşık yapısından kurtulmak için ABD'deki afet yönetimi sistemi rol model alınmıştır. İkinci olarak bu rol model birebir olarak değil de Türkiye'nin kurumsal merkezileşme geleneğine uygun olarak AFAD'ın FEMA' dan farklı olarak koordinasyon dan başka görevler üstlenmesine neden olmuştur. Üçüncü olarak da AFAD'ın bu merkezileşme sürecinde yerel birimler olarak valilik ve belediye yönetimlerine gerektiği kadar yetki devri ve olanak sağlamadığı düşünülmektedir. ABD'deki afet yönetiminin birçok artısı olmasına rağmen kendine göre birçok eksiği olduğu varsayılırsa Türkiye'deki afet yönetiminin ilerleyen dönemlerde büyük ülkelerdeki afet yönetimi sistemine benzer bir seviyeye ulaşacağı söylenebilir. Bu bağlamda, AFAD'ın merkezileşme düşüncesinden kurtularak yerele yetki verilmesi ile daha etkin hale geleceğinden bahsedilebilir.The purpose of this thesis is to investigate Disaster and Emergency Management Authority (AFAD), which oversees disaster management in Turkey, and Federal Emergency Management (FEMA), which manage disaster administration in the USA. In order to make this comparison; disaster managements in both countries need to be understood and clarified within the period from establishments of AFAD and FEMA until now. In this respect, three basic assumptions were developed. Firstly, disaster management system in the USA was taken as a role model, in order to get rid of complex structure of disaster management system in Turkey. Secondly, this role model causes AFAD to undertake other roles apart from coordination in accordance with the institutional tradition of centralization in Turkey unlike FEMA. Finally, in the process of centralization of AFAD, it is thought that AFAD does not enable enough authority and opportunitiest to the governorships and municipal governments. If it is assumed that disaster management in the USA has some disadvantage by it self all though it has some advantages, it might be said that disaster management in Turkey will reach the level, which is similar to developed countries in future. Therefore, it may be mentioned that AFAD will be more effective by giving authority to local governments with getting rid of centralizatio

A new approach for design and control on bridgeless power factor correction circuit

Teknolojinin hızla gelismesi ve degismesi sonucunda ortaya çıkan yeni devre ve kontrol teknikleri nedeniyle istenmeyen harmonik akım ve gerilimlerin olusması kaçınılmaz hale gelmistir. Dogrusal olmayan yükler tarafından üretilen sebeke akım harmoniklerini azaltmak için güç katsayısı düzeltim devreleri gelistirilmistir. Lineer olmayan yükler tarafından üretilen düsük güç katsayısı giris gerilimini bozmakta ve aynı kaynaga baglı diger elemanları etkilemektedir. Klasik güç katsayısı düzeltim devrelerinde kontrol islemi, giris akımının giris gerilimini takip etmesi ilkesine dayanarak gerçeklestirilmektedir. Giris geriliminin sinüs formunda olmaması ve farklı harmonikler içermesi durumunda giris akımı da sinüs formunda olmayacak ve giris gerilimi ile aynı harmonikleri içerecektir. Bu durum, özellikle klasik güç katsayısı düzeltim devreleri bozuk giris gerilimi ile beslendiklerinde önemli bir dezavantajdır. Önerilen kontrol yaklasımında klasik yöntemlerde oldugu gibi giris gerilimi dogrudan referans olarak kullanılmamaktadır. Bunun nedeni, sebeke geriliminin her zaman saf sinüs dalgalı bir sinyal olmamasıdır. Bu yöntemde, örnek alınan sebeke geriliminin sadece sıfır geçis noktaları DSP mikroislemcisi yardımıyla tespit edilerek ideal sinüs dalgası üretilmektedir. Böylece sebeke ile aynı faz ve frekansta sinüzoidal dalga üretilerek referans giris gerilimi elde edilmis olunmaktadır. Bu durumda bozuk sebeke geriliminin etkisiyle meydana gelen akım harmoniklerinin sisteme yansıması önlenmektedir. Güç katsayısı düzeltim devrelerinde kullanılan köprü dogrultucu ve yarıiletken malzemeler iletim kayıplarını artırmaktadır. Bu çalısmada kullanılan dönüstürücü, köprüsüz güç katsayısı düzeltim devresidir. Kullanılan dönüstürücünün diger benzeri dönüstürücülerden önemli bir üstünlügü yarıiletken iletim yolunda olusan kayıpların az olmasıdır. Köprüsüz güç katsayısı düzeltim devresinde köprü dogrultucu ortadan kalkmakta ve iki adet tek fazlı yükseltici tip dönüstürücü kullanılmaktadır. Sistem, IEC 61000&#8211;3&#8211;2 akım harmonikleri standart kosullarını basarıyla saglamaktadır. Tasarımı, denetimi ve anahtarlama teknikleri MATLAB ortamında Simulink blokları kullanılarak yapılmıstır. Köprüsüz güç katsayısı düzeltim devresine önerilen kontrol teknigi uygulanmıs ve deneysel çalısmaları tamamlanmıstır. Elde edilen deneysel sonuçlar ile teorik sonuçlar birbirini desteklemektedir.Undesired voltage and current harmonics in an electricity system have become inevitable because of the new circuits and control techniques appeared with the technological growth. The power factor correction (PFC) circuits have been developed to reduce current harmonics in utility systems produced by nonlinear loads. Poor power factor generated by nonlinear loads disrupts the ac line voltage and effects the other equipments connected to the same source. In conventional PFC circuits, the switch of the converter is controlled such that the input current tracks the input ac line voltage. Since the input voltage is not always a sinusoidal wave and includes different harmonic components, the input current will not be a sinusoidal wave and will be distorted including the same harmonic components of the input voltage. This is an important disadvantage of conventional PFC converters especially when they are fed by a distorted ac line voltage. In the proposed control approach, the input voltage is not directly used as reference as in the conventional methods. This is due the fact that, the input ac mains voltage is not always a sinusoidal wave. In this method, an ideal sine wave is generated by a DSP microprocessor based on detected zero crossing points of the input voltage. Thus, a reference signal is generated with the same phase and frequency of the ac mains voltage. In this manner, the injection of the input current harmonics as the result of the distorted input voltage to the ac mains is prevented. Using bridge rectifier and semiconductor components in these converters increases the conduction losses. The topology used in this study, is a bridgeless PFC converter. An important advantage of this topology over the similar PFC converters is that the conduction losses of the semiconductor switches are lower. This is due to minimum possible number of semicon ductor switches in the current path at any instant of operation, which is two. This topology is composed of two single-phase boost converters without input rectifier as used in other PFC circuits. The system satisfies the conditions of IEC 61000&#8211;3&#8211;2 current harmonics standards successfully. The design, control and switching techniques of the circuit have been carried out using Simulink blocks in MATLAB program. The proposed method and the theoretical analysis are verified by the results of experiments carried out in the laboratory

Ramöz atık havasından ısı geri kazanımı

Tekstil terbiyesinde kullanılan ramözlerin (gergefli kurutucular) ndan atılan atık havada işe dönüştürülemeyen fazla miktarda atık ulunmaktadır. Bu atık enerjinin bir ısı geri kazanım sistemi bacaları enerji b kullanılmadan atılması işletmeler için büyük bir kayıptır. Bu çalışma tarafından tasa tipi bir a işletme suyunun ne kadar ısıtılabileceği araştırılmıştır. Yıkama kulesinin özelliklerinin, kullanılan su debisinin, su sıcaklığının ve atık havadaki nem miktarının geri kazanılan enerji miktarına etkisi incelenmiştir. rlanan ve hava-su teması esasına göre çalışan laboratuar yıkama kulesi konstrükte edilerek ramöz atık havasıyla işletme suyunun ne kadar ısıtılabileceği araştırılmıştır. Yıkama kulesinin özelliklerinin, kullanılan su debisinin, su sıcaklığının ve atık havadaki nem miktarının geri kazanılan enerji miktarına etkisi incelenmiştir

A Study on the Effects of Different Heat-Treatment Parameters on Microstructure–Mechanical Properties and Corrosion Behavior of Maraging Steel Produced by Direct Metal Laser Sintering

Herein, direct aging (aged‐490 °C/6 h) and solution heat treatment and subsequent aging (SHT‐940 °C/2 h + 490 °C/6 h) heat treatments are applied to maraging steel (MS1) produced by direct metal laser sintering (DMLS) method. The effects of these heat treatments on microstructure, phase transformations, mechanical properties, and corrosion properties in MS1 are given in comparison with the as‐built state. Optical microscope (OM) and scanning electron microscope (SEM) is used for microstructure measurements, electron dispersion spectroscopy (EDX), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD) methods are used to determine the phase transformations. Potentiodynamic polarization tests are applied to determine the corrosion resistance of the material, and stereo OM and the Tafel extrapolation method is used to examine the corrosion results. The hardness test is carried out with a Rockwell C method to determine the mechanical character of the material. According to the results obtained, it is determined that the applied heat treatments affect the hardness and corrosion resistance of the material by changing the microstructure and phase transformations of MS1 material produced with DMLS

Effect of RRA Heat Treatment on Corrosion and Mechanical Properties of AA7075

In this study, a retrogression process (R) has been applied to AA7075 at 180, 240, and 370°C for 15, 30, 90, and 120 min. After the retrogression, reaging treatment (RA) was reapplied with T6 conditions (120°C for 24 hr). The effect of different temperatures and time periods of retrogression and reaging temper on exfoliation corrosion (EXCO) of the AA7075 is examined. The EXCO solution was prepared in accordance with the ASTM G34‐01 standard and the samples were kept in the solution for 48hr. Susceptibility of the alloy to EXCO was determined by weight loss detection, macro and microstructure studies, scanning electron microscope, transmission electron microscope, and energy dispersive X‐ray analyses. The mechanical properties of aged samples were determined by hardness, tensile tests, and fractography