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Öğe Bellevalia chrisii sp nov (Asparagaceae) from eastern Anatolia, Turkey(Wiley-Blackwell, 2015) Yıldırım, Hasan; Altıoğlu, Yusuf; Şahin, Bilal; Aslan, SerdarBellevalia chrisii Yldrm & B. Sahin (Asparagaceae) is described and illustrated as a new species from the Malatya province in eastern Anatolia, Turkey. Diagnostic morphological characters, a full description and detailed illustrations are provided on the basis of the type specimen and observations of wild populations. It is morphologically similar to B. rixii and B. crassa but is easily differentiated from both by more numerous and wider leaves, more numerous flowers, less dense fruiting raceme, longer fruiting pedicel and by the shape of the capsule. Moreover, it differs from B. crassa by crimson purple perigone and violaceous anthers. Also, it displays some similarities with B. glauca and has previously been confused with it, although it can be easily distinguished by several morphological features.The conservation status, a distribution map and notes on the biogeography and ecology of B. chrisii are provided.Öğe Bellevalia vuralii B. Sahin & Aslan (Asparagaceae): a new species from SE Turkey(Tubitak Scientific & Technical Research Council Turkey, 2016) Şahin, Bilal; Aslan, Serdar; Karabacak, Osman; Martin, EsraBellevalia vuralii B. Sahin & Aslan is described as a new species of Bellevalia from southeast Turkey. As well as its morphological characteristics and classification with regards to sections, its description, ecology, and relationship with related species are presented and discussed. The somatic chromosome number of these species was defined to be 2n = 8.Öğe Bellevalia vuralii B.Şahin & Aslan (Asparagaceae): a new species from SE Turkey(2016) Şahin, Bilal; Aslan, Serdar; Karabacak, Osman; Martin, EsraBellevalia vuralii B.Şahin & Aslan is described as a new species of Bellevalia from southeast Turkey. As well as its morphological characteristics and classification with regards to sections, its description, ecology, and relationship with related species are presented and discussed. The somatic chromosome number of these species was defined to be 2n 8.Öğe Çankırı İli Meralarının Floristik Özellikleri(2015) Şahin, Bilal; Aslan, Serdar; Ünal, Sabahaddin; Mutlu, Ziya; Mermer, Ali; Urla, Öztekin; Aydoğmuş, OsmanBu çalışmada, Çankırıda yapılan 41 adet mera vejetasyon etüdüne dayalı olarak il meralarının floristik özellikleri incelenmiştir. Vejetasyon etüdü tekerlek-nokta yöntemiyle yapılmıştır. Çalışma sonucunda 46 familya ve 187 cins içinde 327 adet tür tespit edilmiştir. Bu türlerin 38 tanesi buğdaygil, 56 tanesi baklagil, 47 tanesi papatyagil ve 141 tanesi de diğer familyalara aittir. Bitkiyle kaplı alan içerisinde buğdaygil, baklagil ve diğer familyaya ait türler sırayla %36.3, %12.8 ve %50.9 oranlarında bulunmaktadırlar. Yine meralarda en sık rastlanan familyalar sırasıyla Poaceae (3880), Lamiaceae (1676), Fabaceae (1367) ve Asteraceae (802)dir. En yüksek örtüşe sahip 20 türün 10u Poaceae, 1i Fabaceae ve 9u diğer familyalardandır. Meralardaki örnekleme başına ortalama tür sayısı 31.4 (standart sapma8)tür. Meralarda en çok rastlanan cinsler Astragalus (19), Trifolium (7), Centaurea (7), Alyssum (7), Trigonella (5), Ranunculus (5) ve Medicago (5)dur. Çankırı ilinin zengin flora yapısı mera alanlarının ıslahında kullanılabilecek yem bitkilerini içeren önemli bir bitki gen kaynağı olarak belirlenmiştir. Anahtar Kelimeler: Çankırı, mera, floraÖğe A contribution of enigmatic species to Smyrnium galaticum from Turkey(2013) Sağıroğlu, Mehmet; Aslan, Serdar; Şahin, BilalSmyrnium galaticum Czeczott ilk olarak Kuzey Anadolu Çankırı-Eldivan çevresinden Czeczott tarafından toplandı. Türkiye florası hazırlanırken P.F. Stevens tarafından bu tür iyi bilinmeyen türler arasına kondu ve tür ayırım anahtarında yer almadı. Bu makalede türün morfolojik karakterleri tartışıldı. İlave olarak türün tanımı genişletildi, ekolojisi, koruma statusü, S. cordifolium’dan farkları ve merikarplarının fotoğrafları verildi.Öğe Crocus thracicus (Iridaceae), a new species from north-western Turkey(Magnolia Press, 2015) Yüzbaşıoğlu, Sırrı; Aslan, Serdar; Özhatay, NerimanCrocus thracicus is described as a new species from Thrace, the European part of Turkey. The white form of this species was wrongly referred to an albino form of C. chrysanthus by Mathew in the Flora of Turkey. It grows in open stony places and in sparse Quercus sp. and Paliurus spina-christi clearings at elevations between 45-170 m. It is compared with the morphologically similar C. alexandri and C. weldenii. A description, detailed illustrations, photograps of metephase plate, karyotype and idiogram of new species are presented.Öğe Effect of CTAB concentration in the electrolyte on the tribological properties of nanoparticle SiC reinforced Ni metal matrix composite (MMC) coatings produced by electrodeposition(Elsevier, 2013) Kılıç, Fatih; Gül, Harun; Aslan, Serdar; Alp, A.; Akbulut, HatemIn this study, a nickel sulfate bath containing SiC nanoparticles (between 100 and 1000 nm) was used to obtain hard and wear-resistant nanoparticle reinforced Ni-SiC MMCs on steel surfaces for anti-wear applications, such as dies, tools and working parts. The influence of stirring speed and surfactant concentration on particle distribution, microhardness and wear resistance of nano-composite coatings has been studied. The nickel films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The depositions were controlled to obtain a specific thickness (between 50 and 200 mu m) and particle volume fraction in the matrix (between 0.02 and 0.12). The hardness of the resulting coatings was also measured and found to be 280-571 Hv, depending on the particle volume in the Ni matrix. The effects of the surfactant on the zeta potential, co-deposition and distribution of SiC particles in the nickel matrix, as well as the tribological properties of composite coatings, were investigated. The tribological behaviors of the electrodeposited SiC nano composite coatings sliding against M50 steel ball (empty set 10 mm) were examined on a CSM Instrument. All friction and wear tests were performed without lubrication at room temperature and in the ambient air (relative humidity 55-65 %). The results showed that the wear resistance of the nano composites was approximately 2-2.2 times higher than unreinforced Ni deposited material. (c) 2012 Elsevier B.V. All rights reserved.Öğe Effect of particle concentration on the structure and tribological properties of submicron particle SiC reinforced Ni metal matrix composite (MMC) coatings produced by electrodeposition(Elsevier Science Bv, 2012) Gül, Harun; Kılıç, Fatih; Uysal, Mehmet; Aslan, Serdar; Alp, A.; Akbulut, HatemIn the present work, a nickel sulfate bath containing SiC submicron particles between 100 and 1000 nm was used as the plating electrolyte. The aim of this work is to obtain Ni-SiC metal matrix composites (MMCs) reinforced with submicron particles on steel surfaces with high hardness and wear resistance for using in anti-wear applications such as dies, tools and working parts for automobiles and vehicles. The influence of the SiC content in the electrolyte on particle distribution, microhardness and wear resistance of nano-composite coatings was studied. During the electroplating process, the proper stirring speed was also determined for sub-micron SiC deposition with Ni matrix. The Ni films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The depositions were controlled to obtain a specific thickness (between 50 and 200 mu m) and volume fraction of the particles in the matrix (between 0.02 and 0.10). The hardness of the coatings was measured to be 280-571 HV depending on the particle volume in the Ni matrix. The tribological behaviors of the electrodeposited SiC nanocomposite coatings sliding against an M50 steel ball (empty set 10 mm) were examined on a tribometer. All the friction and wear tests were performed without lubrication at room temperature and in the ambient air (with a relative humidity of 55-65%). The results showed that the wear resistance of the nanocomposites was approximately 2-2.2 times more than those of unreinforced Ni. (C) 2011 Elsevier B.V. All rights reserved.Öğe Effect of reciprocating sliding speed on the tribological performance of nano SiCp reinforced Ni-metal matrix composites produced by electrocodeposition(2012) Gül, Harun; Akbulut, Hatem; Aslan, Serdar; Alp, A.In the present work, Ni/SiC metal matrix composite (MMC) coatings were prepared from a modified Watt's type electrolyte containing nano-SiC particles by direct current (DC) plating method to increase wear resistance of the electro co-deposited Ni. SiC nano particles with average particle size of 0, 1-1 ?m were co-deposited with nickel matrix on the steel substrates. For this purpose, several studies were carried out to optimize deposition parameters for specific applications. The depositions were controlled to obtain the specific thickness (between 175-200 ?m) and particle volume fraction in the matrix (between 0.03 and 0.10). The hardness of the resultant coatings was measured and found to be 280-571 HV depending on the particle concentration in the electrolyte and therefore, particle volume in the Ni matrix. The tribological tests were performed by a reciprocating ball-on disk apparatus sliding against M50 steel ball (ø10 mm). All the friction and wear tests were performed under the unlubricated conditions at room temperature and in the ambient air (relative humidity 55-65%). The wear tests were carried out at different sliding velocities of 50 mm/s, 100 mm/s and 150 mm/s by using a constant dead load of 1.0 N. It was detected that increasing sliding speed resulted to increase wear rate but decreasing friction coefficient due to change in wear mechanism. Increasing sliding speed showed formation of tribo induced oxides up to 20 g/l SiCp in the electrolyte and wear mechanism was controlled by temperature induced fatigue wear. Further increase in the SiCp in the electrolyte caused an abrasive type of the wear. Copyright © 2012 American Scientific Publishers All rights reserved.Öğe Improvement possibilities and effects of vegetation subjected to long-term Heavy Grazing in the steppe rangelands of Sivas(2014) Ünal, Sabahaddin; Mutlu, Ziya; Urla, Öztekin; Yıldız, Hakan; Aydoğdu, Metin; Şahin, Bilal; Aslan, SerdarMeralar gerçekte hayvanlar içi n yem kaynakları olarak bilinirler. Ayn ı zamand a meralar, s u kaynağ ı , zengi n flora ve fauna olma özelliği ve dinlenme alanı gibi çok yönlü kullanımlar için potansiyel kaynaklara sahipti r. Meralar uzun süreli optimum fayda sağlamak için dikkatli kullanılmalı ve muhafaza edilmelidirler. Bu alanlar hala kötü yönetim nedeniyle bozulmakta ve bu bozulma süreci devam etmektedi r. Mevcut mera durumu iyi yönetim uygulamalarıyla tersine çevrilebili r. Bu sebeple Sivas ili meralarında 2008, 2009 ve 2010 yıllarında arazi çalışmaları yürütülmüştü r. Vejetasyon etüt çalışmaları lup ile modifiye edilmiş tekerlek nokta yöntemi il e Sivas meraların ı temsi l eden 103 durakta yapılmıştı r. Bu çalışmanı n sonucund a bitkiyl e kapl ı alan % 60,68 olarak bulunmuştu r. Azalıc ı v e çoğalıc ı bitki türlerini n kaplam a oranları sırayl a % 15,53 v e % 22,23 tü r. İncelenen mera duraklarında iyi, orta ve zayıf durumda olan duraklar sırayla 6, 62 ve 35 olarak bulunmuştu r. Toplam durakların 97 adeti mera durumu orta ve zayıf sınıflamada yer almıştı r. Diğer taraftan, mera sağlığı açısından yapılan sınıflamada 26 durak sağlıklı, 35 durak riskli, 42 durak sorunlu olarak bulunmuştu r. Toplam 77 adet durak mera sağlığ ı açısından riskl i v e sorunludu r. Çalışm a sonuçları , meraları n yavaş olarak bozulm a eğiliminde olduğunu ve bu alanların uygun ıslah ve yönetim uygulamaları ile başarılı olarak orijinal hallerine dönme potansiyeli taşıdığını, göstermişti r.Öğe Liver Transplantation in a Patient with Absent Inferior Vena Cava: Case Report(2020) Dönmez, Ramazan; Kargı, Ahmet; Yazar, Şerafettin; Aslan, Serdar; Peker, Kemal; Polat, Kamil YalçınTransplantation procedure used if the recipient and donor do not have a special anatomicalvariation today; left lateral segment in the pediatric age group, and right lobe in the adult agegroup. Biliary atresia in children and various liver diseases like metabolic events in adults arethe major causes of liver transplantation. Liver transplantation is challenging in the patientswith congenital vascular anomalies. Infrahepatic interruption of the inferior vena cava (IVC)is a rare congenital anomaly with the incidence of 0.6% to 2% and mostly found withcongenital heart disease. In this study we tried to report a 58-year old male patient with adiagnosis of decompensated liver cirrhosis caused by the hepatitis B virus (HBV) who washospitalized for the first time for living donor liver transplantation.Öğe Nadir Endemik Bir Tür Üzerine Notlar: Rhaponticoides pythiae (Azn. & Bornm.) M.V.Agab. & Greuter / Yitiktülüşah(2019) Sağıroğlu, Mehmet; Aslan, Serdar; Vural, MecitG.V. Aznavour tarafından Yalova’dan toplanan örneklere dayalı olarak bilim dünyasınaCentaurea pythiae olarak tanıtılan takson Türkiye Florası yazılırken, Centaurea amasiensisaltında sinonim olarak verilmiştir. Daha sonra ise bu tür yeniden canlandırılıpRhaponticoides pythiae olarak yeniden değerlendirilmiştir. Bu tür günümüze kadar uzun birsüre aranmış, ancak bir flora çalışması sırasında 2010 yılında yeniden toplanmıştır. Kocaeli,Safiye Köyü’nde çok kısıtlı bir alanda yetişen bu türün tehdit kategorisi CR (B2ab(i,ii,iii)olarak önerilmiştir.Öğe A new record for Turkey: Michauxia nuda A.DC. (Campanulaceae)(Tubitak Scientific & Technical Research Council Turkey, 2010) Aslan, Serdar; Vural, Mecit; Şahin, Bilal; Ergin, Esra; Kaya, Ömer FarukMichauxia nuda A.DC. (Campanulaceae) is recorded for the first time (C8 Siirt province) from Turkey. The diagnostic characters of M. nuda are described and its habitat and conservation status are indicated. Besides, it is illustrated, and a distribution map is presented. Notes on collecting number of type specimen of this species are provided.Öğe An overview of biodiversity and conservation status of steppes of the Anatolian Biogeographical Region(Springer, 2016) Ambarlı, Didem; Zeydanlı, Uğur S.; Balkız, Özge; Aslan, Serdar; Karaçetin, Evrim; Sözen, Mustafa; Vural, MecitThe Anatolian Biogeographical Region is unique in the Palearctic realm, with high plant and butterfly species richness and populations of globally threatened birds, mammals and herptiles (amphibians and reptiles). It is a place of diverse land-use practices, dating back to the earliest farming practices in the world. Among 10,930 species of vascular plants, birds, butterflies, mammals and herptiles distributed in Turkey, we identified 1130 living predominantly in steppic environments and being classified either as threatened, near-threatened or data deficient at the national level, if not globally. A total of 28 effective protected areas were present in the region, covering 1.5 % of the 391,597 km(2) land area. Only 16.2 % of the threatened and near-threatened species (n = 809) were distributed within the protected area network, ranging from 94.1 % for birds to as low as 12.9 % for vascular plants. The total area of steppe and steppe forest vegetation has been reduced by at least 44 % of its former extent due to diverse habitat destructive activities. The most significant threats arise from unsustainable agricultural activities including overgrazing, conversion to croplands and afforestation. To maintain steppe diversity, we propose a "to-do list", including mainstreaming biodiversity, effective implementation of Turkey's Rangeland Act, conducting effective environmental impact assessments, establishing an effective site network for steppe biodiversity conservation and filling gaps in scientific knowledge.Öğe The Preparation of Zeolite/Ag Composite Powders by Electroless Deposition Process(Springer, 2014) Uysal, Mehmet; Karslıoğlu, Ramazan; Gül, Harun; Aslan, Serdar; Keskin, S.Y.; Okumuş, S.C.; Alp, A.Core-shell Ag-coated zeolite composite powders were synthesized using silver electroless deposition process, which was carried out in an ammonia-based coating solution containing silver nitrate as a precursor material. The influence of the chemical components and powder concentration in the Ag coating was investigated by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction techniques. The zeolite/Ag composite powders were fabricated in order to find an antibacterial material and a new implant material based on the microstructural change of zeolite/Ag composites powders using different parameters of Ag deposition.Öğe Presence of Centaurea regia Boiss. subsp. regia (Subgen. Cynaroides (Boiss. ex Walp.) Dostál, Compositae) in Turkey(2010) Aslan, Serdar; Vural, Mecit; Şahin, Bilal; Çelik, Sezgin; Karavelioğulları, Faik AhmetCentaurea regia subsp. regia (Subgen. Cynaroides) taksonu Handel-Mazetti tarafından, Diyarbakır - Cizre arasından not edilmiş, fakat toplanmamıştır. Bu nedenle Wagenitz, bu taksonu Türkiye florasında süpheli kayıt başlığı altında belirtmiştir. Bu çalışmada, bu taksonun ülkemizdeki varlığı kanıtlanmıştır. Taksonun tanıtıcı özellikleri, yetişme ortamı ve koruma durumu belirtilmiştir. Ayrıca bu makalede taksonun, fotoğrafları ve yayılış haritası da verilmiştir.Öğe Rangeland Health, Condition and Biodiversity in Kırşehir Province(2019) Mutlu, Ziya; Ünal, Sabahaddin; Mermer, Ali; Urla, Öztekin; Şahin, Bilal; Aslan, SerdarRangeland improvement and management have recently become more important that many new projects have been also initiated and conducted throughout Turkey. There is a great responsible for the provinces in the Central Anatolia Region on those implementation projects. In this framework, this study was designed that could contain vegetation surveys in representative sites for rangelands of Kırşehir province in 2008 year, at the same time their assessment, and conclusion were also performed too. The 36 rangeland sites were surveyed with the modified-loop method. The results of vegetation surveys were analyzed and determined rangeland condition and health classes for each sites. The vegetation cover was measured as 65.35%. The rates of decreasers and increasers cover were 11.54% and 35.26%, respectively. The studied sites numbers were one, 30 and 5 for good, fair, and poor conditions, respectively. The 35 sites of total sites were identified as fair and poor in condition based on the rangeland condition classes. On the other hand, 8 sites were found at healthy, 20 sites at risky and 8 sites at unhealthy in rangeland health categories. Total site numbers of the last two classes were 28.Rangeland biodiversity were calculated as 0.229 by Simpson’s index. Survey results showed that rangelandshave been overgrazed and seemed degradation. Firstly this trend should be stopped and secondly urgentmeasures should be implemented for restoration.Öğe Reciprocating sliding speed effect on the tribological properties of SiCp reinforced Ni MMCs deposited by electroplating(European Conference on Composite Materials, ECCM, 2012) Gül, Harun; Aslan, Serdar; Akbulut, Hatem; Alp, AhmetIn the present work, Ni/SiC metal matrix composite (MMC) coatings were prepared from a modified Watt's type electrolyte containing nano-SiC particles by direct current (DC) plating method to increase wear resistance of Ni. The influence of surfactant content on co-deposition of SiC particles (0.1-1.0 ?m size range) in the matrix, and tribological properties were investigated. The influence of sliding speed on the tribological performances of the coatings was investigated by a reciprocating ball-on disk apparatus. The wear tests were carried out at different sliding speeds by using a constant load. Wear resistances and friction coefficients of Ni/SiC composites were decreased by increasing sliding speed because of temperature-controlled surface oxidation. The change in wear mechanisms by changing surfactant content and sliding speeds were also comprehensively studied and, in general, decreasing surface damage was obtained by increasing sliding speed.Öğe The Results of Liver Transplantation Performed In a Single Center Due To Hepatocellular Carcinoma(Duzce Univ, Fac Medicine, 2023) Aslan, Serdar; Yazar, Serafettin; Kargi, Ahmet; Kurnaz, Eray; Sahin, Dilek; Peker, Kemal; Astarcioglu, IbrahimObjective: Hepatocellular cancer (HCC) is the most common malignancy of the hepatobiliary system. There are significant differences in the global spread of HCC. It is the major cause of death in patients with cirrhosis. Its molecular pathogenesis is highly complex and heterogeneous. Major risk factors for the development of HCC are chronic hepatitis B virus (HBV) infection, chronic hepatitis C virus (HCV) infection and alcohol related liver cirrhosis. Hepatocellular cancer is rarely seen in the first 4 decades of life, except in communities where HBV infection is hyperendemic.Methods: The study was conducted by retrospectively scanning the files of 204 patients diagnosed with HCC who applied to Organ Transplantation Center between 21.09.2014 and 13.04.2019. Patients were transplanted liver by being classified according to Milan criteria, San Francisco [University of California San Francisco (UCSF)] criteria, and Barcelona Clinic Liver Cancer (BCLC) criteria.Results: The median age of the patients was 58.03 (range 31 to 72). 170 of the patients were men and 34 of them were female. Liver transplantation (LT) was performed from cadaveric donors to 31 patients and from living donors to 173 patients. There is a significant relationship between the life span of the patients and their gender. Female patients have a longer life expectancy [t (202) = 2.963, p =0.003]. A significant relationship was found between life expectancy and surgical classification [F (3) = 3.008, (p =0.031)].Conclusions: In patients diagnosed with HCC and undergoing LT; the gender being female and the classification method before transplantation affect life expectancy.Öğe The Role of Early Period ERCP in Acute Biliary Pancreatitis?(Duzce Univ, 2021) Aslan, Serdar; Peker, Kemal; Yildirgan, Mehmet IlhanObjective: Acute pancreatitis;It can be defined as a clinical picture that occurs as a result of non_bacterial inflammation of the pancreas and may progress with pathological findings. For years, various studies have been conducted on the use of Endoscopic Retrograde Cholangiopancreotography and Endoscopic Sphincterotomy for therapeutic purpose in Acute Pancreatitis. For years, various studies have been conducted on the use of Endoscopic Retrograde Cholangiopancreotography and Endoscopic Sphincterotomy for therapeutic purpose in Acute Pancreatitis. In our study, we aimed to examine either the effectiveness of Endoscopic Retrograde Cholangiopancreotography and Endoscopic Sphincterotomy in patients with mild severity, and how the endoscopic procedure affects the course of the disease. Methods: In this study, patients with mild pancreatitis were selected among the patients who applied to the Department of General Surgery, of Ataturk University Faculty of Medicine and diagnosed with acute biliary pancreatitis (ABP). After the patients were separated according to the mild pancreatitis, early (within 72 hours) and late period, they were randomly selected to be performed Endoscopic Retrograde Cholangiopancreotography and Endoscopic Sphincterotomy. 59 patients were detected in this way. Results: Twelve (20.3%) of the patients included in our study were male, and 47 (79.7%) were female, and their ages were between 25-75 years (mean 64.3 years). Two groups were created in order to perform ERCP/ES in the early and late periods. All patients had acute onset abdominal pain and serum amylase levels have been ranging between (1012-7660 UI/L). Conclusions: In patients with mild acute biliary pancreatitis, there is no significant difference in the early (first 72 hours) ERCP/ES results compared to the results of patients with ERCP/ES in the late period.