297 research outputs found
Data Mining Applications On Web Usage Analysis & User Profiling
Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2003Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2003Tez çalışmasında veri madenciliği teknolojisi, fonksiyonları ve uygulamaları özetlenmiştir. OLAP teknolojilerine ve veri ambarlarına da veri madenciliğinin anahtar kavramları olarak değinilmiştir. Uygulama kısmında müşteri ve alışveriş kalıpları analizi için bir internet parakendecisinin işlemsel verileri kullanılmıştır. Müşteri segmentasyonu ve kullanıcı betimleme gibi konulardaki kurumsal kararları desteklemek amacıyla veri içerisindeki kalıplar çıkarılmaya çalışılmıştır.This thesis gives a summary of data mining technology, its functionalities and applications. OLAP technology and data warehouses are also introduced as the key concepts in data mining. The usage of data mining on the internet and the decisions based on internet usage data are introduced. In the application section a web retailer’s transactional data is used for analyzing customer and shopping patterns.Hidden patterns within the data are tried to be extracted in order to support business decisions such as user profiling and customer segmentation.Yüksek LisansM.Sc
Perceived Coach Attitudes and Behaviors Scale: Development and Validation Study
The purpose of the study was to develop a scale, which will serve to determine how attitudes and behaviors of the coaches are perceived by the athletes. The scale, named as “Perceived Coach Attitudes and Behaviors Scale” (PCABS) was developed through various processes including exploratory and confirmatory factor analysis. Following the literature review process in the beginning stage, focus group interviews were conducted. As a result of literature review process and focus group interviews an item pool of 61 items was formed, and after gathering the opinions and critics of experts in the area of language and sports science, the final form of the scale was constructed. The exploratory factor analysis (EFA) on 200 athletes revealed a construct comprised of 25 items and 3 sub-dimensions. Subsequently, confirmatory factor analysis (CFA) conducted on 266 athletes confirmed the structural validity of the scale composed of 24 items and 3 sub-dimensions. The first sub-dimension named "Characteristic Features ", with an internal consistency value of 0.88, consisted of items 1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 18, 20, and 23. The second sub-dimension named "Knowledge and Skills Accumulation" consisted of items 13, 14, 15, 16, 17, 19, 21, 22, and 24 had an internal consistency value of 0.86. The final sub-dimension named "Being Fair" consisted of 5th and 12th items with an internal consistency value of 0.56. Items 1, 2, 3, 4, 6, 7, 8, 9, 10, 18, 20 and 23 were reverse coded items of the scale.As a conclusion, the analysis revealed that “Perceived Coach Attitudes and Behaviors Scale”, with its three sub-dimensions and 24 items, is a structurally valid and reliable scale, can be used to identify the athletes' perceptions about their coaches
Investigation of the Effect of Geometric Shape and Ratio of Steel Fibers on Concrete Properties
Birçok araştırmada betonun teknik özelliklerini artırmak için farklı cins ve tiplerdeki liflerle çalışmalar yapılmıştır. Genellikle sonyıllarda betonun mekanik özeliklerinin öncelikli olan yerlerde çelik lif tercih edilmektedir. Bu çalışmada, tarafımızca şekil verilerekoluşturulan 2 farklı çelik lif tipi (Z, C şeklinde) ve 80/60 çelik lifi, çimento ağılığının 0.0, 0.10, 0.15 ve 0.20 oranlarındakullanılmıştır. Bu farklı şekillere sahip çelik liflerin, taze betonda oluşturdukları hava %’si miktarı ve işlenebilme özelliğigözlenirken; sertleşmiş betonda ise basınç, eğilme ve aşınma dayanımlarına olan etkileri incelenmiştir. Lifin şekli ve oranının, tazeve sertleşmiş beton özellikleri üzerinde etkili olduğu görülmüştür. Taze ve sertleşmiş betonda en optimum özellik, 80/60 lifinin%10 kullanılmasıyla elde edilmiştir.Many studies have been conducted with fibers of different types and shapes to increase the technical properties of concrete. Generally, steel fiber has been preferred in the places where the mechanical properties of concrete have priority in recent years. In this study, 2 different steel fiber types (Z, C shaped) and 80/60 steel fiber, which are formed by us, were used in the ratios of cement weights at 0.0, 0.10, 0.15 and 0.20. While the amount of air content and the workability of the steel fibers of these different shapes added in fresh concrete were observed; In hardened concrete, its effects on compressive strength, flexural strength and abrasion resistance were investigated. The shape and ratio of the fiber have been shown to be effective on fresh and hardened concrete properties. The optimum feature in fresh and hardened concrete has been achieved by using 10% of 80/60 fiber
Atipik hipofiz adenomu olgularının insidansı, hormonal dağılımı ve postoperatif takibi
AMAÇ: Hipofiz adenomu tanısı ile operasyon uygulanan olgularımızdan patoloj ik tanısı atipik hipofiz adenomu olanların görülme sıklığı, hormonal aktivitesi ve postoperatif takipleri araştırılmıştır. YÖNTEM ve GEREÇlER: Kliniğimizde Ocak 2009 - Mayıs 2012 tarihleri arasında endoskopik endonasal transsfenoidal yolla opere edilen 146 hipofiz adenomu olgusundan WHO 2004 kriterlerine göre patoloj isi atipik hipofiz adenomu olarak saptanan 13 olgu çalışmaya dahil edildi. BUlGULAR: Histoloj ik olarak 133 hasta tipik hipofiz adenomu (%91,1), 13 hasta ise atipik hipofiz adenomu (%8,9) idi. Bu hastaların 10 tanesi erkek (%76,9), 3 tanesi kadındı (%23,1). Yaş dağılımı 27 ile 80 arasında idi (ortalama 52.7). Dokuz olgu nonsekretuar adenom (%69,3), 3 olgu prolaktinoma (%23,1), 1 olgu ise somatostatinoma (%7,6) idi. Dört olguda hipofizer apopleksi mevcuttu (%30,7). Tipik hipofiz adenomlu hastalardan 11 tanesinde nüks saptanırken (%8,2), atipik hipofiz adenomlu olgulardan ise 5 tanesinde nüks adenom (%38,4) nedeniyle tekrar operasyon yapıldı. SONUÇ: Atipik hipofiz adenomları iyi bir patoloj ik inceleme yapıldığında çok da nadir görülen adenom tipi değildir. Tümör rekürrensinde tek başına belirleyici olmamakla birlikte tipik adenomlara göre çok daha yüksek oranda rekürrense neden olduğu unutulmamalıdır. Bu yüzden bu hastalarda total tümör eksizyonu, eğer mümkün olmuyorsa postoperatif daha yakın takip ile ek tedavi uygulamalarının kullanılması gereklidir.AIM: To assess the incidence, hormonal activity and postoperative follow up of the cases that are histopathologically diagnosed as atypical pituitary adenoma (APA) in our series. MATERIAL and METHODS: In this study, 13 atypical pituitary adenoma cases, by the WHO 2004 criteria, among the 146 pituitary adenoma patients operated on in our clinic between January 2009 and May 2012 by endoscopic endonasal transsphenoidal approach were included. results: In histological studies, 133 cases were diagnosed as typical pituitary adenoma (91.1%) and 13 cases were APAs (8.9%) of which 10 were male (76.9%) and 3 were female (23.1%), ranged between 27 and 80 (mean 52.7) ages. Histopathological distribution of APAs was 9 non- secretory adenomas (69.3%), 3 prolactinomas (23.1%) and 1 somatostatinoma (7.6%). Asymptomatic pituitary apoplexy was diagnosed in 4 cases (30.7%). Eleven cases of typical pituitary adenomas (8.2%) and 5 cases of the atypical pituitary adenomas (38.4%) were re-operated due to tumor recurrences. CONCLUSION: Accurate histopathological examination shows that atypical pituitary adenoma is not a rare disease. Although it is not the only determinant, APAs are more prone to recurrence than typical adenomas. In our opinion, if total resection is not possible for the patients with APA, close postoperative follow up and additional curative therapy modalities are needed
Novel SNARE Complex Polymorphisms Associated with Multiple Sclerosis: Signs of Synaptopathy in Multiple Sclerosis
Background: It is well known that axonal degeneration plays a role in disability in patients with multiple sclerosis, and synaptopathy has recently become an important issue.Aims: To investigate the possible roles of selected synaptic and presynaptic membrane protein genetic polymorphisms (VAMP2, SNAP-25, synaptotagmin, and syntaxin 1A) in patients with multiple sclerosis.Study Design: Case-control study.Methods: A total of 123 patients with multiple sclerosis and 192 healthy controls were included. The functional polymorphisms of specific SNARE complex proteins (VAMP2, synaptotagmin XI, syntaxin 1A, and SNAP-25) were analyzed by polymerase chain reaction.Results: Significant differences were detected in the genotype and allele distribution of 26-bp Ins/Del polymorphisms of VAMP2 between patients with multiple sclerosis and control subjects; Del/Del genotype and Del allele of VAMP2 were more frequent in patients with multiple sclerosis (p=0.011 and p=0.004, respectively). Similarly, Ddel polymorphism of SNAP-25 gene C/C genotype (p=0.059), syntaxin 1A T/C and C/C genotypes (p=0.005), and synaptotagmin XI gene C allele (p=0.001) were observed more frequently in patients with multiple sclerosis. CC, syntaxin rs1569061 1A gene for 33-bp promoter region TC haplotypes, and synaptotagmin XI gene were found to be associated with an increased risk for multiple sclerosis (p=0.012). Similarly, GC haplotype for rs3746544 of SNAP-25 gene and rs1051312 of SNAP-25 gene were associated with an increased risk for multiple sclerosis (p=0.022).Conclusion: Genetic polymorphisms of SNARE complex proteins, which have critical roles in synaptic structure and communication, may play a role in the development of multiple sclerosis
Determination of a monumental Quercus coccifera tree in Gökçeada
Ağaç-insan ilişkisinde önemli bir yere sahip olan anıt ağaçlar, ağaca duyulan hayranlık ve sevginin
önemli simgelerindendir. Quercus coccifera L. (dikenli pırnal, kermes meşesi) gibi genellikle çalı
formundaki bireylerle temsil edilen ağaçlar içerisinde ileri çap ve boylara ulaşmış olanlar son derece
nadirdir. Türkiye’de bugüne kadar 9 anıt ağaç önerisi yapılan dikenli pırnal ağacının anıtsal boyutlara
ulaşmış bir bireyi de Gökçeada’da bulunmuştur. Makalenin amacı bu ağacın anıtsal değerini
saptayarak anıt ağaç olarak tescil edilmesi için bilimsel altlık oluşturmaktır. Gövde çapı (1.30 m’deki)
106 cm ve boyu da 12,5 m olan söz konusu dikenli pırnal ağacının ŞAD (Şimdiki Anıtsal Değeri) > MADtür
değeri (Minimum Anıtsal Değeri) 69 > 44 olarak belirlenmiştir. Arazide bir şapelin yanında bulunan
ağaç, bu dini tesisin bir parçası konumundadır. O nedenle, hem boyutsal hem de folklorik yönüyle anıt
ağaç olarak tescil edilmesi uygun olacaktır.Monumental trees, which have an important place in the tree-human relationship, are important
symbols of admiration and love for the tree. Trees such as Quercus coccifera L. (Kermes oak), which
are generally represented by individuals in the form of bushes, are extremely rare. In Turkey, an
individual has reached monumental dimensions of the nine so far detected Kermes oak tree was also
found in Gökçeada. The purpose of the paper is to establish a scientific base for the monumental value
of this tree to be registered as a monumental tree. The Kermes oak tree, whose trunk diameter (at
1.30 m) is 106 cm and its length is 12,5 m, has been determined as ŞAD (Current Monumental Value)>
Item Value (Minimum Monumental Value) 69> 44. This tree with a chapel in the field is part of this
religious facility. Therefore, it would be appropriate to register it as a monumental tree in terms of
both dimensional and folkloric aspects
Hepatoprotective effects of B-1,3-(D)-Glucan on bortezomib-induced liver damage in rats
The aim of this study was to evaluate the effects of beta -1,3-(D)-glucan as an antioxidant and tissue protective agent and study the biochemical, histopathologic, and immunohistochemical effects of first therapeutic proteasome inhibitor bortezomib on the liver for treating relapsed multiple myeloma. The experiment included 36 adult male rats, which were divided into four treatment groups: control (healthy); bortezomib-treated; beta-1,3-D-glucan-treated; and bortezomib + beta-1,3-(D)-glucan-treated. Each group was subdivided into two subgroups based on time of sacrifice (48 or 72 h). After the experiments, superoxide dismutase (SOD) activity and lipid peroxidation (LPO) amounts were determined, and immunohistochemical and histopathological changes were examined in all rat liver tissues. beta -1,3-(D)-Glucan treatment normalized changes of LPO and stimulated an over activity of endogenous SOD. The results of the histopathologic parameters showed that treatment with beta -1,3-(D)-Glucan in the bortezomib group ameliorated the development of non-specific reactive hepatitis (NSRH) and Kupffer cell activation via NF-kB. Administration of beta -1,3-(D)-Glucan is effective in reversing tissue damage induced by bortezomib in rat livers.Bu çalışmanın amacı, relaps multiple miyelom tedavi etmek için kullanılan ilk terapötik proteazom inhibitörü olan bortezomibin
karaciğer üzerine immunohistokimyasal, histopatolojik ve biyokimyasal etkilerini araştırmak ve bir antioksidant ve doku koruyucu
ajan olarak B-1,3-(D)-glukanın etkilerini değerlendirmekdi. Deney; kontrol (sağlıklı), bortezomib ile tedavi, B-1,3-(D)-glukan ile
tedavi ve bortezomib + B-1,3-(D)-glukan ile tedavi olmak üzere dört tedavi grubuna bölünen 36 yetişkin erkek sıçan içerdi. Her bir
grup sakrifikasyon zamanına (48 veya 72 saat) göre iki alt gruba ayrıldı. Deneylerin bitiminden sonra, süperoksit dismutaz (SOD)
aktivitesi ve lipid peroksidasyon (LPO) miktarları ölçüldü ve tüm sıçan karaciğer dokularında immünohistokimyasal ve histopatolojik
değişiklikler incelendi. B-1,3-(D)-glukan ile tedavi LPO değişikliğini normalize etti ve endojen SOD aktivitesi aşırı uyardı. Histopatolojik
parametrelerin sonuçları, bortezomib grubunda B-1,3-(D)-glukan ile tedavi NF-kB yoluyla Kupffer hücre aktivasyonunu ve non-spesifik
reaktif hepatit (NSRH) gelişimini regüle ettiğini gösterdi. B-1,3-(D)-glukan uygulaması, sıçan karaciğerinde bortezomibin neden olduğu
geri döndürülebilir doku hasarında efektifdir
Spontaneous Breathing in Early Acute Respiratory Distress Syndrome: Insights From the Large Observational Study to UNderstand the Global Impact of Severe Acute Respiratory FailurE Study
OBJECTIVES: To describe the characteristics and outcomes of patients with acute respiratory distress syndrome with or without spontaneous breathing and to investigate whether the effects of spontaneous breathing on outcome depend on acute respiratory distress syndrome severity. DESIGN: Planned secondary analysis of a prospective, observational, multicentre cohort study. SETTING: International sample of 459 ICUs from 50 countries. PATIENTS: Patients with acute respiratory distress syndrome and at least 2 days of invasive mechanical ventilation and available data for the mode of mechanical ventilation and respiratory rate for the 2 first days. INTERVENTIONS: Analysis of patients with and without spontaneous breathing, defined by the mode of mechanical ventilation and by actual respiratory rate compared with set respiratory rate during the first 48 hours of mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Spontaneous breathing was present in 67% of patients with mild acute respiratory distress syndrome, 58% of patients with moderate acute respiratory distress syndrome, and 46% of patients with severe acute respiratory distress syndrome. Patients with spontaneous breathing were older and had lower acute respiratory distress syndrome severity, Sequential Organ Failure Assessment scores, ICU and hospital mortality, and were less likely to be diagnosed with acute respiratory distress syndrome by clinicians. In adjusted analysis, spontaneous breathing during the first 2 days was not associated with an effect on ICU or hospital mortality (33% vs 37%; odds ratio, 1.18 [0.92-1.51]; p = 0.19 and 37% vs 41%; odds ratio, 1.18 [0.93-1.50]; p = 0.196, respectively ). Spontaneous breathing was associated with increased ventilator-free days (13 [0-22] vs 8 [0-20]; p = 0.014) and shorter duration of ICU stay (11 [6-20] vs 12 [7-22]; p = 0.04). CONCLUSIONS: Spontaneous breathing is common in patients with acute respiratory distress syndrome during the first 48 hours of mechanical ventilation. Spontaneous breathing is not associated with worse outcomes and may hasten liberation from the ventilator and from ICU. Although these results support the use of spontaneous breathing in patients with acute respiratory distress syndrome independent of acute respiratory distress syndrome severity, the use of controlled ventilation indicates a bias toward use in patients with higher disease severity. In addition, because the lack of reliable data on inspiratory effort in our study, prospective studies incorporating the magnitude of inspiratory effort and adjusting for all potential severity confounders are required
Identifying associations between diabetes and acute respiratory distress syndrome in patients with acute hypoxemic respiratory failure: an analysis of the LUNG SAFE database
Background: Diabetes mellitus is a common co-existing disease in the critically ill. Diabetes mellitus may reduce the risk of acute respiratory distress syndrome (ARDS), but data from previous studies are conflicting. The objective of this study was to evaluate associations between pre-existing diabetes mellitus and ARDS in critically ill patients with acute hypoxemic respiratory failure (AHRF). Methods: An ancillary analysis of a global, multi-centre prospective observational study (LUNG SAFE) was undertaken. LUNG SAFE evaluated all patients admitted to an intensive care unit (ICU) over a 4-week period, that required mechanical ventilation and met AHRF criteria. Patients who had their AHRF fully explained by cardiac failure were excluded. Important clinical characteristics were included in a stepwise selection approach (forward and backward selection combined with a significance level of 0.05) to identify a set of independent variables associated with having ARDS at any time, developing ARDS (defined as ARDS occurring after day 2 from meeting AHRF criteria) and with hospital mortality. Furthermore, propensity score analysis was undertaken to account for the differences in baseline characteristics between patients with and without diabetes mellitus, and the association between diabetes mellitus and outcomes of interest was assessed on matched samples. Results: Of the 4107 patients with AHRF included in this study, 3022 (73.6%) patients fulfilled ARDS criteria at admission or developed ARDS during their ICU stay. Diabetes mellitus was a pre-existing co-morbidity in 913 patients (22.2% of patients with AHRF). In multivariable analysis, there was no association between diabetes mellitus and having ARDS (OR 0.93 (0.78-1.11); p = 0.39), developing ARDS late (OR 0.79 (0.54-1.15); p = 0.22), or hospital mortality in patients with ARDS (1.15 (0.93-1.42); p = 0.19). In a matched sample of patients, there was no association between diabetes mellitus and outcomes of interest. Conclusions: In a large, global observational study of patients with AHRF, no association was found between diabetes mellitus and having ARDS, developing ARDS, or outcomes from ARDS. Trial registration: NCT02010073. Registered on 12 December 2013
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