İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
DSpace@İSTÜN, Üniversite mensupları tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Energy, exergy, exergoenvironmental, and exergoenviroeconomic assessment of a two stroke UAV small engine using JP5 aviation fuel and hydroxy (HHO) gas
(Elsevier, 2024) Özer, Salih; Tunçer, Erdal; Demir, Üsame; Gülcan, Halil Erdi; Çelebi, Samet
Hydroxy gas (HHO) is a gas produced by the electrolysis of water, which involves breaking down water molecules (H2O) into hydrogen (H2) and oxygen (O2) gases. When the electricity used for electrolysis comes from renewable energy sources, the resulting hydrogen can be classified as 'green hydrogen.' Therefore, by using renewable green energy sources to produce HHO gas, its application in internal combustion engines can promote clean combustion and enhance sustainability. This study explores the enhancement of performance and emission characteristics in a two-stroke Unmanned Aerial Vehicle (UAV) engine using Hydroxy gas (HHO), a green energy source produced via water electrolysis. The primary objective is to improve engine efficiency and reduce environmental impacts by employing HHO in dual-fuel mode with JP5 aviation fuel. Addressing a clear research gap in the literature, this study is the first to evaluate the energy, exergy, exergoenvironmental, and exergoeconomic aspects of a two-stroke, air-cooled UAV engine using the JP5+HHO fuel blend. Experiments were conducted at five shaft speeds (3250, 3750, 4500, 5250, 6250 rpm) and four HHO flow rates (1.0, 1.5, 2.0, 4.0 lpm). The results demonstrate that incorporating HHO gas leads to a significant improvement in engine performance, with a 10% average reduction in Brake Specific Fuel Consumption (BSFC) and a 10% increase in exergy efficiency. Additionally, the JP5+HHO 4 lpm mixture reduces exergy destruction by approximately 10% and increases heat transfer exergy by 3–10%. On the environmental front, while HHO slightly increases CO2 emissions, the exergoenvironmental impact rises by a manageable 4%. Importantly, the high HHO flow rate (4 lpm) achieves a 2% average reduction in both exergoenvironmental and exergoeconomic impacts. These findings underscore the potential of HHO as a sustainable fuel source, offering both performance gains and reduced environmental and economic costs.
Autologous ovarian tissue transplantation: Preoperative assessment and preparation of the patient
(Wolters Kluwer Health, 2024) Turan, Volkan; Öktem, Özgür
Importance: Ovarian tissue cryopreservation (OTC) is an innovative and established fertility preservation method. More than 150 live births have been reported worldwide to date with the use of this strategy. OTC is one of the options to preserve fertility in prepubertal girls and for women who have time constraints and/or contraindications for ovarian stimulation for oocyte/embryo freezing before cancer treatment. The success rate of the ovarian tissue transplantation (OTT) depends on many interrelated factors. Therefore, preoperative evaluation and preparation of the candidate patients for the procedure are of paramount importance. Objective: In this review, our aim was to provide a guide for the clinicians, which demonstrates step-by-step assessment and preparation of the patients and ovarian tissue samples for transplantation. Evidence Acquisition: We searched for published articles in the PubMed database containing key words, such as OTT, OTC, preoperative assessment, primordial follicle density, and cancer, in the English-language literature until May 2024. We did not include abstracts or conference proceedings. Results: OTT is still a developing method as an effective fertility preservation approach. It is essential to perform a thorough preoperative evaluation of the patient to improve the success rates of transplantation. Conclusions and Relevance: Preoperative evaluation and preparation of women for ovarian transplantation surgery should include safety management to prevent reimplantation of malignant cells, transplanting ovarian tissue with minimum follicle loss and the decision of the best transfer site.
Non‑cirrhotic portal fbrosis/idiopathic portal hypertension: APASL recommendations for diagnosis and management
(Springer Nature, 2024) Shukla, Akash; Rockey, Don C.; Kamath, Patrick S.; Kleiner, David E.; Singh, Ankita; Vaidya, Arun; Koshy, Abraham; Goel, Ashish; Dökmeci, A. Kadir; Meena, Babulal; Philips, Cyriac Abby; Sharma, Chhagan Bihari; Örmeci, Necati; Sarin, Shiv Kumar
Since the Asian Pacific Association for the Study of the Liver (APASL) published guidelines on non-cirrhotic portal fibrosis/idiopathic portal hypertension in 2007, there has been a surge in new information, especially with the introduction of the term porto-sinusoidal vascular disorder (PSVD). Non-cirrhotic intra-hepatic causes of portal hypertension include disorders with a clearly identifiable etiology, such as schistosomiasis, as well as disorders with an unclear etiology such as non-cirrhotic portal fibrosis (NCPF), also termed idiopathic portal hypertension (IPH). This entity is being increasingly recognized as being associated with systemic disease and drug therapy, especially cancer therapy. An international working group with extensive expertise in portal hypertension was assigned with formulating consensus guidelines to clarify the definition, diagnosis, histological features, natural history, and management of NCPF/IPH, especially in the context of PSVD. The guidelines were prepared based on evidence from existing published literature. Whenever there was paucity of evidence, expert opinion was included after detailed deliberation. The goal of this manuscript, therefore, is to enhance the current understanding and help create global consensus on the issues surrounding NCPF/IPH.
Comparison of the effects of four laser wavelengths on Medication-Related Osteonecrosis of the Jaw (MRONJ) in a murine model: An in vivo photobiomodulation study
(Ivyspring International Publisher, 2024) Ayhan, Mustafa; Gedik, Betül; Kalelioğlu, Ekrem Emir; Kundakçıoğlu, Abdulsamet; Küçükgergin, Canan; Turgut, Cevat Tuğrul; Kocaelli, Hümeyra; Alatlı, Fatma Canan; İşsever, Halim; Ademoğlu, Evin; Yaltırık, Mehmet
Background: This study aims to investigate the effectiveness of lasers at various wavelengths in treating medication-related osteonecrosis of the jaw (MRONJ) using biochemical, clinical scoring, micro CT analysis, and histopathological methods. The study follows the ARRIVE guidelines to ensure robust and transparent research. Methods: In our study, there were 6 groups, including one SHAM group, one CONTROL group, and four experimental groups, with 8 rats in each individual group. Each rat received antiresorptive drug intraperitoneally for 4 weeks and then had the left second molar in the mandible extracted. All animals were sacrificed at the end of the 12th week. In the experimental groups, lasers at wavelengths of 405nm, 445nm, 660nm, and 808nm were applied to the animals. Parameters such as serum vitamin D levels, bone density and bone volume at the extraction site, new bone formation, dead bone count, inflammatory cell count, and epithelial regeneration were examined. Additionally, clinical scoring was conducted after sacrifice. The laser parameters included power density, area, time, fluence, and mode (continuous wave), and the light was administered using a fiber with a Gaussian profile. Statistical analyses were performed with the NCSS (Number Cruncher Statistical System) 2007 Statistical Software (Utah, USA) package program. The results were evaluated at the p<0.05 significance level. Results: According to the results obtained from our study, new bone formation in all experimental groups was significantly higher than in the SHAM and CONTROL groups. Furthermore, the 660nm and 808nm wavelengths increased serum vitamin D levels significantly. The most successful outcomes were observed in clinical scoring, dead bone count, epithelial cell regeneration, and bone density in the 660nm and 808nm wavelength groups. Conclusions: The combined use of lasers at 660nm and 808nm wavelengths may yield successful results in treating MRONJ.
Komplike olmayan üriner sistem enfeksiyonlarında lokal antibiyotik direncinin çok merkezli taranması: 37 merkezden 1850 hasta
(Ankara Microbiology Society, 2024) Cinislioğlu, Ahmet Emre; Cinislioğlu, Nazan; Öztürk, Metin İshak; Akkaş, Fatih; Aksakallı, Tugay; Atilla, Mustafa Kemal; Atiş, Gökhan; Aydın, Hasan Rıza; Balcı, Uğur; Bayrak, Ömer; Bedir, Selahattin; Biçer, Hüseyin; Çevik, Gökhan; Çift, Ali; Çiftçi, Halil; Coşkun, Burhan; Demirdöğen, Şaban Oğuz; Demirkol, Mehmet Kutlu; Dinçer, Murat; Doğan, Ahmet Emin; Dursun, Murat; Erdemir, Fikret; Erkan, Anıl; Eryıldırım, Bilal; Görür, Sadık; Hızlı, Fatih; Kadıhasanoğlu, Mustafa; Kalkan, Senad; Karabulut, İbrahim; Keskin, Mehmet Zeynel; Kızılay, Fuat; Köse, Osman; Küçük, Eyüp Veli; Odabaş, Öner; Oksay, Taylan; Özbey, Isa; Şefik, Ertuğrul; Sönmez, Mehmet Giray; Tek, Mesut; Tuğlu, Devrim; Tuncay, Ömer Levent; Usta, Mustafa Faruk; Yılmaz, Sercan; Kadıoğlu, Ateş
Bu çalışma, Türkiye’nin yedi farklı coğrafi bölgesinde komplike olmayan üriner sistem enfeksiyonu tanısı olan hastalardan elde edilen ayaktan üriner izolatlara göre en sık izlenen patojenleri tespit etmek ve bu patojenlere karşı kullanılan antibiyotiklerin direnç oranlarının coğrafi bölgelere göre anlamlı farklılık gösterip göstermediğini belirlemek amacıyla yapılmıştır. Mart 2021 ile Ağustos 2022 arasında, Türkiye genelindeki 37 farklı merkezde yapılan tetkikler sonucunda komplike olmayan üriner sistem enfeksiyonu tanısı koyulan ve pozitif idrar kültürleri olan 18 ile 65 yaş arası hastalar çalışmaya dahil edilmiştir. Araştırmaya katılan merkezler, idrar kültürlerinin verilerinin standardizasyonunu sağlamak için mikrobiyoloji laboratuvarlarında Avrupa Antimikrobiyal Duyarlılık Test Komitesi tarafından disk difüzyon yöntemini kullanan merkezlerden seçilmiştir. Bu çalışmaya, dahil edilme kriterlerine uyan toplam 1850 hasta dahil edilmiştir. Escherichia coli izolatlarının antibiyotik direnç oranlarının dağılımının analizi, ampisilin, fosfomisin ve nitrofurantoin dirençlerinde coğrafi bölgelere göre istatistiksel açıdan anlamlı farklılıkların olduğunu saptamıştır (sırasıyla p< 0.05, p< 0.05, p< 0.05). Güneydoğu Anadolu Bölgesi fosfomisin ve trimetoprimsülfametoksazol direncinin en yüksek olduğu bölge olarak tespit edilmiştir (sırasıyla; %27.4 ve %35.3). Bunun yanı sıra nitrofurantoin direncinin en yüksek olduğu bölge %35.7 oranıyla Doğu Anadolu Bölgesi ve siprofloksasin direncinin en yüksek olduğu bölge %51 oranıyla İç Anadolu Bölgesi olarak belirlenmiştir. Çalışma, komplike olmayan üriner sistem enfeksiyonlarının tedavisinde kullanılan antibiyotiklere direncin coğrafi bölgelere göre farklılık gösterdiğini ortaya koymuştur. Bu kapsamlı, ulusal prospektif araştırmanın, komplike olmayan üriner sistem enfeksiyonu için ampirik tedavi planlayan klinisyenlere değerli öngörüler sağlayacağı düşünülmektedir.
