The Euler Characteristic of Finite Categories

We first assign a quadratic form and in particular a rational number to every finite category. In some cases, we call this rational number the Euler characteristic of the category. We show that this extends the definition of Leinster to a larger family of finite categories. Leinster's formula for the Euler characteristic of the Grothendieck construction of a diagram of categories requires the existence of a coweighting associated with the Grothendieck construction. Here we give a formula with no assumptions about the Grothedieck construction itself but only some conditions on the diagram. We also discuss the invariance and noninvariance of several definitions, in the literature, of Euler characteristics under weak equivalences of the canonical model category structure and the Thomason model category structure on categories respectively

Functional outcomes of bone marrow aspirate concentrate application in osteoarthritis of the knee

Background: Osteoarthritis (OA) of the knee is a very common musculoskeletal disorder. Although total knee replacement is a suitable option in the treatment of severe OA, it has some limitations when performed in the early stage and early age. Bone marrow aspirate concentrate (BMAC), which is rich in mesenchymal stem cells, is promising due to its potentially regenerative and symptomatic effects in many disorders of the musculoskeletal system. This study aims to investigate the efficacy of BMAC in terms of functional recovery in OA of the knee joint.Methods: Total of 52 patients with unilateral symptomatic knee OA but no inflammatory disease, advanced malalignment or instability were enrolled in this study. Bone marrow aspirate was collected from the iliac crest in one session, prepared using a manufactured kit and the patients received intra-articular injections of this BMAC. The mean age of the patients was 59.2±7.4 and the mean follow-up period was 22.1±3.6 months. Functional outcomes of the patients were evaluated using Modified Cincinnati and Tegner Lysholm scoring systems.Results: It was observed that both Lysholm and Cincinnati scores of the patients were statistically significantly higher throughout the follow-up period as compared to the period before the procedure (p=0.0001). There was no statistically significant difference in Lysholm and Cincinnati ratings between gender, side and body mass index groups throughout the follow-up period (p >0.05). It was found that the results of the patients with Kellgren-Lawrence Grade 4 severe joint arthrosis were statistically significantly lower (p <0.05).Conclusions: Considering the functional outcomes of the patients up to two years, it was observed that the application of concentrated bone marrow aspirate provided functional recovery in arthrosis of the knee joint

Analysis and applicability of Mersin region wind speed data with artificial neural networks

In this study, wind speed data were analyzed in order to provide energy to the heating and electrical systems of a house with renewable energy sources in Mersin-Mut region. Three-year wind speed data is taken from the Turkey General Directorate of Meteorology in the region. Annual estimation was made with artificial neural networks using 28-day wind speed data for the studied area. Some of the wind data were used for training of the neural network, and some were used for testing. In the artificial neural network model, the most successful model was obtained by changing the number of neurons in the hidden layer. In the analysis made using eight neurons in the hidden layer, the lowest MAE and RMSE error values were calculated. While the number of neurons was eight, MAE and RMSE values were obtained as 0.4056 and 0.5403, respectively. In addition, analysis of wind data with WAsP software has been carried out for this region. Thus, the average instantaneous wind speed was determined according to the analysis studies

Halı sahada oluşan futbol yaralanmaları

Objectives: Football injuries that occur during football matches played on synthetic fields and the features of these injuries were investigated and the data was pursued for the prevention and reduction of these injuries. Patients and methods: All adolescent and adult trauma cases who admitted to the Emergency Department with football injuries on synthetic fields were retrospectively investigated. Nine hundred and eighty-five male cases were detected with a mean age of 30.1±4.2 years (range 15-57 years). Age, gender, times of admittance to the Emergency Department, site of injury, type of injury, and clinical result data of the cases were examined. Results: 19:00 to 24:00 hours (n=852, 86.5%) and weekdays were the most frequent admittance times. It was detected that lower-extremities (n=583, 59.2%) were the most commonly affected body parts and the upper-extremity injuries (n=281, 28.6%) and the head and neck injuries (n=75, 7.6%) were the second and third most commonly seen injuries, respectively. The most frequently observed injury types were contusions, abrasions and hematomas in all cases (n=364, 37.0%). Sprains/ strains were the second most common types of injuries (n=343, 34.8%). When the final diagnoses of all cases were examined, it was determined that the anterior talofibular ligament injuries were the second most frequent after softtissue injuries (n=217, 22%). Conclusion: Football matches on synthetic fields can lead to serious orthopedic injuries. Investigation of the mechanisms of these injuries, which cause workday and economic losses, will be a guide for the future studies on the prevention of these injuries

KOBİlerin Finansal Problemlerinin Çözümünde Risk Sermayesi Finansman Modeli

Technology Based Firms (TBF) , defined as firms whose activitiesembrace a significant technology component as a major source of competitiveadvantage, are important source of products. There is a wide variety of sources ofexternal financial funds for Technology Based Firms.Hovewer, despite number of potential sources available, many TBF hassome financial problems. Venture Capital is one of major source that firms can copewith their's financial problems .It can take two main forms externally managed investment, wheninvestments are made via externally managed venture capital funds which reinvestreturn in small firms, and internally managed investment, when investments inindividual independent ventures are selected and management by corporate itself.Finally, Venture Capital is an important source for TBF and it's development

The morphologic relationship of the lesser trochanter with the femoral neck and greater trochanter

Background: The anatomy of the proximal femur comprises important landmarks for many orthopedic surgical procedures. However, this area exhibits morphological differences depending on race, gender and age. Besides being the insertion area of the hip flexor muscles, the lesser trochanter is also used as an angular reference in many orthopedic surgical procedures. The aim of this study is to investigate the morphologic relationship of the lesser trochanter with the femoral neck and greater trochanter.Methods: Around 67 dry femur bones (32 left, 35 right) belonging to humans of unknown gender that belong to the Ankara University Medical Faculty, Department of Anatomy were used in this study. The morphologic relationship of the lesser trochanter (TRMI) with the femoral neck (FN) and greater trochanter (TRMJ) was studied and the results were provided in a table.Results: The measured mean lesser trochanter and greater trochanter tip distance was 67.5±4.9mm (60mm-75mm). The angle between the tip of the lesser trochanter and the center of the femoral neck was measured as 35.050±5.060 (290-420) degrees. The distance between the tip of the lesser trochanter and the center of the femoral neck was measured as 15±2.8mm (10mm-20mm).Conclusions: In addition to the angular relationship of the lesser trochanter with the femoral neck, its relationship in terms of distance with the greater trochanter and femoral neck are the anatomic relationships that are noteworthy for the lesser trochanter, which is used as a landmark during orthopedic surgical procedures

In spontaneous intracerebral hematoma patients, prediction of the hematoma expansion risk and mortality risk using radiological and clinical markers and a newly developed scale

Objective: In patients with spontaneous intracerebral hematoma (ICH), early-stage hematoma expansion has been associated with poor prognosis in literature. This study aimed to develop predictive parameter(s) as well as a new scale to define hematoma expansion and short-term prognosis in patients with ICH. Methods: In 46 patients with ICH, Glasgow Coma Scale (GCS) scores, non-contrast CT (NCCT) markers (hematoma volume on admission and follow-up, hypodensity, intraventricular hemorrhage, blend and island sign, BAT score), and modified Rankin Scale scores were evaluated for predicting the hematoma expansion risk and mortality risk. Furthermore, a newly developed scale called the ‘HEMRICH scale’ was constituted using the GCS score, hematoma volumes, and some NCCT markers. Results: Roc-Curve and Logistic Regression test results revealed that GCS score, initial hematoma volume value, hypodensity, intraventricular haemorrhage, BAT score, and HEMRICH scale score could be the best markers in predicting hematoma expansion risk whereas GCS score, intraventricular haemorrhage, BAT score, hematoma expansion, and HEMRICH scale score could be the best markers in predicting mortality risk (p = 0.01). Moreover, Factor analysis and Reliability test results showed that HEMRICH scale score could predict both hematoma expansion and mortality risks validly (Kaiser-Meyer-Olkin test value = 0.729) and reliably (Cronbach’s alpha = 0.564). Conclusion: It was concluded that the GCS score, intraventricular haemorrhage, and BAT score could predict both hematoma expansion risk and mortality risk in the early stage in patients with ICH. Furthermore, it was suggested that the newly produced HEMRICH scale could be a valid and reliable scale for predicting both hematoma expansion and mortality risk

Positive effects of angiotensin-converting enzyme (ACE) inhibitor, captopril, on pentylenetetrazole-induced epileptic seizures in mice

Purpose: To evaluate the effects of an angiotensin-converting enzyme (ACE) inhibitor, captopril, on pentylenetetrazole (PTZ)-induced seizures and post-seizure hippocampal injury. Materials: Thirty-five male Balb-c mice weighing 30 - 33 g were divided into control, saline PTZ, s(erum physiologic 1 ml/kg as solvent), positive control (valproic acid 200 mg/kg), captopril (25 mg/kg/day for 7 days), and captopril (50 mg/kg/day for 7 days) groups. PTZ (60 mg/kg) was administered thirty minutes after medication administration to induce epileptic seizures. The animals were observed for 30 min to record Racine stages, the time of the first myoclonic jerk (FMJ), and the occurrence of the first generalized tonic-clonic seizure (GTCS). Cornu Ammonis (CA)1, CA2, CA3, and the dentate gyrus (DG) of the hippocampus underwent histopathological examinations. The levels of total oxidant status (TOS), oxidative stress markers (total antioxidant status, TAS), and oxidative stress index (OSI) were measured in the brain tissue. Results: Compared to PTZ group, 25 mg/kg captopril decreased seizure scores and delayed FMJ and GTCS (p &lt; 0.05). Histopathological assessment demonstrated that both 25 and 50 mg/kg captopril alleviated neuronal injury in CA1, CA2, CA3, and DG compared to PTZ (p &lt; 0.05). Also, TOS and OSI levels in the brain tissue were reduced by both 25 and 50 mg/kg doses of captopril (p &lt; 0.05). Conclusion: Captopril favorably improves epileptic seizure parameters and acts against post-seizure neuronal injury in the hippocampus. Captopril may be a drug of choice in epileptic individuals with hypertension. Keywords: Captopril, Angiotensin-converting enzyme, Epilepsy, Pentylenetetrazole, Neuronal damag

A panchromatic boradiazaindacene (BODIPY) sensitizer for dye-sensitized solar cells

A novel distyryl-substituted boradiazaindacene (BODIPY) dye displays interesting properties as a sensitizer in DSSC systems, opening the way to further exploration of structure-efficiency correlation within this class of dyes

SAKARYA NEHRİ ÜZERİNDEKİ HİDROLİK YAPILARIN NEHİR AKIMI REJİMİNE OLAN ETKİLERİNİN ARAŞTIRILMASI

Barajlar, üzerine inşaa edildikleri akarsuların Hidrolojik, Morfolojik ve Sediment Taşıma Kapasitesi gibi karakteristik özelliklerinde zaman içinde önemli ölçüde değişiklikler meydana getirmektedirler. Bu çalışmada, Orta Sakarya Havzasında Sarıyar, Gökçekaya ve Yenice Barajlarının ve Pamukova Hidroelektrik Santrali (HES) ve Regülatörünün inşa edilmesinden sonra Aşağı Sakarya Nehrinde meydana gelen hidrolik değişimler araştırılmıştır. Her bir barajın tam kapasite işletmeye alınmasından önce ve sonraki durumlar için nehirdeki akımların değişimi ayrı ayrı incelenmiştir. Aşağı Sakarya Nehri üzerindeki Doğançay ve Botbaşı istasyonlarına ait değerler her bir baraj ve regülatörün işletmeye alındığı tarihlerin öncesi ve sonrası akım değişimleri grafikler halinde gösterilmektedir. Ayrıca, her iki istasyona ait maksimum anlık feyezan akımları kullanılarak gelmesi muhtemel taşkınlardaki değişimler incelenmektedir. Sonuçlar incelendiğinde; Nehirde taşkın pik debileri düşerken, nehir rejiminin düzenlendiği görülmüştür