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The use of geopolymer in place of ordinary Portland cement for concrete design and constructure is gaining attraction due to environmental and health considerations. Geopolymers must have high gamma radiation shielding competence in order for them to be useful for radiation shielding concrete. In an attempt to improve the gamma absorption capacity of a metakaolin-based geopolymer matrix, 10 % (GEO-10Y), and 20 % (G-20Y) yttria (Y2O3) was mixed with GEO through a solid-state reaction process. In this study, the influence of adding yttria on the physical and gamma shielding parameters of GEO was investigated. The densities of GEO, GEO-10Y and GEO-20Y were obtained as 2.28, 2.52 and 2.37 g/cm3, respectively. Through simulation using FLUKA code, the mass attenuation coefficients (MAC) and other relevant shielding quantities were estimated. The MACs of GEO, GEO-10Y, and GEO-20Y were within the range of 0.0213–6.6429 cm2/g, 0.0282–13.3923 cm2/g, and 0.0291–14.5136 cm2/g, respectively. The addition of yttria improved the gamma photon shielding competence of the metakaolin-based geopolymer by increasing the MAC and reducing photon buildup factors within 15 keV–15 MeV photon energy range. The shielding effectiveness of the yttria-doped GEO compares well with conventional shielding materials. Yttria-doped geopolymer can be used to produce effective and environmentally-friendly gamma shielding concrete.

Firmalarda, ihtiyaçlara yönelik gelen taleplerin doğru şekilde işlenmesi hem iş sürecini hızlandırır hem de ortaya çıkabilecek sorunları bertaraf eder. Geliştirme, destek, sorun çözme gibi farklı konulardaki taleplerin, verimli ve doğru kişilerce çözülmesi için öncelikle ilgili alt departmana yönlendirilmesi gerekir. Yönlendirmeler belirli kişilerce elle gerçekleştirilebilir. Ancak firma büyüklüğüyle doğru orantılı olarak gelen talep sayısının çok olması süreci zorlaştırıp zaman kaybına yol açmaktadır. Özellikle bilişim sektöründe hizmet veren kurumsal firmalarda taleplerin otomatik olarak alt-departmanlara aktarılabilmesi, işin verimliliğinin ciddi şekilde arttırabilir. Bu ihtiyacın giderilmesi içi metni işleyerek içerisinden kolaylıkla bilgi çıkarımını sağlayabilen metin madenciliği ve makine öğrenmesi yöntemleri kullanılabilir. Çalışmamızda, Detaysoft Danışmanlık firmasına ait gelen taleplerin doğru şekilde alt departmana yönlendirilmesini sağlayan bir sistem önerilmiştir. Sistem performansının ölçülebilmesi amacıyla gerçek müşteri taleplerinden oluşan 2103 veri toplanmış ve işaretlenmiştir. Toplanan verilerin varsayımlardan bağımsız olarak doğru şekilde işaretlenmesi için de veriye göre sınıf etiketlerinin belirlendiği temellendirilmiş teoriden faydalanılmıştır. Ham metinlerin vektörleştirilmesi için kelime çantası ve türevlerinin (TF, TFIDF) yanı sıra GloVe ve Word2Vec gibi kelime gömme yöntemleri de denenmiş ve hangi vektörleştirme yönteminin daha başarılı olduğu irdelenmiştir. Ayrıca gereksiz kelimelerin ve sadece kelime köklerinin kullanılmasının talep sınıflandırmaya etkileri analiz edilmiştir. Yapılan analizler sonucunda SVM algoritmasını kullanan modellerin %79 gibi iyi sayılabilecek bir başarım ile gelen talebi doğru şekilde sınıflandırabildiği gözlemlenmiştir. Elde edilen sonuçların, talep sınıflandırma konularındaki gelecek çalışmalara hem vektörleştirme hem de ön işlem süreçleriyle alakalı ışık tutması beklenmektedir.

In this paper, an automatic invoice processing system, which is in great demand among private and public companies, was proposed. The proposed system supports all invoice file types that can be submitted by companies. Companies can easily submit invoices to the system via the web interface or email, and all invoices submitted to the system are queued and processed sequentially. If the invoice is a text file, the invoice information is extracted from the text by using template matching. If the invoice is an image, the text and table areas are detected and extracted. For table detection, we used both image processing based and YOLOv5-based deep learning method. Cell extraction was then performed from the extracted table images. As a result of these processes, all text and table cells were obtained as images and these images were converted into machine-readable text using the open-source software Tesseract OCR. Tesseract already provides trained models for English and Turkish. However, these models do not provide successful results for invoices submitted by companies in Turkish. Therefore, the new fine-tuned model trained with invoices in Turkish was used for OCR. The experimental results showed that the trained Turkish model was more accurate than the Turkish and English models provided by Tesseract. In addition, the YOLOv5-based table detection model was more accurate than the image-processing-based table detection method.

In photodynamic therapy, the knowledge of the penetration depth for thelight is needed in order to ensure that the optical energy received by thetumorous tissue. In this study, the optical penetration depths of 635 nm laserlight in chicken breast tissue have been measured by using 8 tissue sampleswith different thicknesses between 2.5 mm and 9.0 mm. Transmitted lightintensities through the tissue samples have been measured with 11 differentoptical power values in the range of 130mW – 660mW. Measurement results foreach power value have been analyzed according to the Beer-Lambert law. With thehelp of statistical analyzes, it has been determined that the opticalpenetration depth of the light in biological tissue does not depend on itsoptical power.

This paper investigates that what are the determinants of target PE in the case of Turkish Stock Market. The general outputs: i) Projected dividend yield is the dominant factor on PE. ii) Boosted investments and growing top-line raise PE ratio. iii) PE ratios come down as companies’ financial leverage and working capital needs grow. iv) Although stabilizing foreign exchange risks and gross profit margins with the aid of hedge tools and product diversity of the companies decreases the acceleration of profitability, it eventually augments PE ratio. Data from Borsa İstanbul covering 2000-2014 term have been modeled by GMM.

Diyanet İşleri Başkanlığı tarafından basılan takvim, yıllık 3 milyonu aşan tirajı ve 10 milyondan daha fazla okuyucusu ile dikkate değer bir din algısı oluşturma, değiştirme ve devam ettirme aracıdır. Takvimlerin bu yönünün akademik açıdan fazla incelenmemiş olmaması bizi bu konuyu çalışmaya yöneltti. Bu çalışmada 2002, 2007 ve 2011 yılı Diyanet İşleri Başkanlığı takvimlerindeki metinler, metin analizi yöntemleriyle incelenip takvimlerdeki din algısı değişimi ortaya konulmuştur. Kurumsal devamlılıktan beklenenin aksine üç dönem kıyaslandığında çok ciddi bir algı değişimi gözlenmiştir, çoğu konu ilgi dışı bırakılırken, çoğu konu da takvimlere dahil edilmiştir.

Background: Contrast enhanced magnetic resonance cholangiography is a novel technique and promising method in demonstrating biliary tree anatomy and evaluating biliary disorders. However, to date, there are a limited number of studies that have focused on the impact of this technique. Aims: We aimed to evaluate the additional role of contrast enhanced MR cholangiography (MRC) and compare contrast enhanced MRC with T2-weighted (w) magnetic resonance cholangiopancreatography (MRCP) in the diagnosis of biliary disorders. Study Design: Diagnostic accuracy study. Methods: The T2w-MRCP and contrast enhanced MRC sequences of 31 patients whose gold standard test results were available were scored visually for the existence of pathological findings with regard to any of the biliary diseases. Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) was used as the contrast agent. The correlation values were determined according to the statistical analysis made from those scores and the sensitivity, specificity and accuracy values of each sequence were detected as well. Results: We detected that the correlation values with gold standard methods of contrast enhanced MRC sequences were significantly higher than the ones of T2w-MRCP sequences. The correlation ratios of T2w-MRCP sequences were between 26 and 34%, while those for contrast enhanced MRC sequences were between 81 and 83% for the first reader and the correlation ratios of T2w-MRCP sequences were between 10 and 61%, whereas those of contrast enhanced MRC were between 79 and 81% for the second reader The mean sensitivity, specificity and accuracy values of T2w-MRCP sequences were 14.3-42.5%, 85-89.2% and 59.3-72.5%, respectively, while the mean sensitivity, specificity and accuracy values of contrast enhanced MRC sequences were 100%, 86.7% and 93.2-93.3%, respectively. Conclusion: We suggest that obtaining of contrast enhanced MRC sequences in addition to the T2w-MRCP can be useful in the diagnosis of many diseases in relation with biliary tree.

Software collaboration platforms where millions of developers from diverse locations can contribute to the common open source projects have recently become popular. On these platforms, various information is obtained from developer activities that can then be used as developer metrics to solve a variety of challenges. In this study, we proposed new developer metrics extracted from the issue, commit, and pull request activities of developers on GitHub. We created developer metrics from the individual activities and combined certain activities according to some common traits. To evaluate these metrics, we created an item-based project recommendation system. In order to validate this system, we calculated the similarity score using two methods and assessed top-n hit scores using two different approaches. The results for all scores with these methods indicated that the most successful metrics were binary_issue_related, issue_commented, binary_pr_related, and issue_opened. To verify our results, we compared our metrics with another metric generated from a very similar study and found that most of our metrics gave better scores that metric. In conclusion, the issue feature is more crucial for GitHub compared with other features. Moreover, commenting activity in projects can be equally as valuable as code contributions. The most of binary metrics that were generated, regardless of the number of activities, also showed remarkable results. In this context, we presented improvable and noteworthy developer metrics that can be used for a wide range of open-source software development challenges, such as user characterization, project recommendation, and code review assignment.

PURPOSEWe aimed to assess the feasibility and reproducibility of real-time elastography (RTE) for displaying the effects of morphological changes in the ovary in polycystic ovary syndrome (PCOS).METHODSForty-eight patients diagnosed with PCOS and 48 healthy women were enrolled in the study. Ultrasonography and RTE were performed on the 3rd day of the menstrual cycle. Evaluations were performed independently by two radiologists. Ovarian volume, number of follicles, elasticity pattern, and strain ratio were measured. Elasticity patterns were assessed as hard (type 1; blue or blue-green), moderate (type 2; green or green-yellow) or soft (type 3; red or orange-red).RESULTSBoth radiologists determined the elasticity pattern as mostly type 1 in the PCOS group and type 3 in the control group (P < 0.01). The mean strain ratios obtained by the first and second radiologist were 6.1±1.8 (2.7–10.1) and 6.0±1.5 (3.0–9.0) in PCOS and 3.3±1.2 (1.7–7.2) and 3.2±0.9 (1.7–6.8) in the control group, respectively (P < 0.001). Interobserver agreement was moderate for the elasticity pattern (κ=0.48) and good for the strain ratio (intraclass correlation coefficient, 0.77). A strain ratio of 3.8 was determined as the optimized cutoff point by receiver operating curve analysis. Strain ratio was correlated with the ovarian volume and the number of detected follicles (P < 0.001).CONCLUSIONElasticity pattern and strain ratio can help identify morphological changes that make PCOS ovaries stiffer than normal ovaries.

This paper examines the gamma-ray shielding features of some selected tellurite-based glasses in the form of xMoO _3 (100−x)TeO _2 (20 ≤ x ≤ 50 mol%). Mass attenuation coefficients ( μ _m ) of these glasses have been calculated using Geant4 toolkit and XCOM program for photon energy range of 1 keV—1000 MeV. The correlation factor (R ^2 ) between these two methods was found to be almost one. Shielding effectiveness for these glasses has been estimated by computing half value layer (HVL), effective atomic number ( Z _eff ), and mean free paths (MFP). It was noticed that the heavy metal oxide of TeO _2 plays an important role in improving the shielding effectiveness of the glasses. The Mo20Te80 glass has shown the promising properties to serve for gamma ray protection applications as compared with many conventional concretes and other newly developed glasses.

PURPOSEWe aimed to evaluate the effectiveness of diffusion-weighted magnetic resonance imaging (DW-MRI) and apparent diffusion coefficient (ADC) values in the diagnosis of acute appendicitis and differentiation of perforated and nonperforated appendicitis cases, with histopathologic correlation. MATERIALS AND METHODSSixty consecutive patients (34 males, 26 females; mean age, 35.6±15.5 years; range, 17–83 years) with a presumptive diagnosis of acute appendicitis were included in this prospective study. With a 1.5 Tesla MRI unit, DW-MRI examinations were performed with b values of 50, 400, and 800 s/mm2. The mean ADC values of case and control groups, as well as in perforated and nonperforated groups were compared. RESULTSOf the 60 cases, 44 had a radiological diagnosis of acute appendicitis, and 16 were regarded as normal. Of the 40 patients who underwent surgical operation, 12 had a histopathological diagnosis of perforated appendicitis, and 28 had nonperforated appendicitis. Mean ADC value in patients with acute appendicitis (1.01±0.26×10-3 mm2/s) was lower than the control group (1.85±0.13×10-3 mm2/s) (P < 0.001). Mean ADC value of the perforated group (0.79±0.19×10-3 mm2/s) was lower than the nonperforated group (1.11±0.22×10-3 mm2/s) (P < 0.001). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy rate of DW-MRI in the diagnosis of acute appendicitis were 97.5%, 100%, 97.5%, 100%, and 98.1%, respectively. CONCLUSIONDW-MRI and ADC quantification are effective in the diagnosis of acute appendicitis, both in perforated and nonperforated cases.

PURPOSEWe aimed to present our clinical experience with the renal artery catheterization (RAC) technique, which reduces the volume of intra-arterial contrast media (ICM) used during endovascular aortic repair (EVAR), and describe the short-term results of this technique. MATERIALS AND METHODSWe retrospectively evaluated 16 patients (15 males and one female) who underwent EVAR between March 2011 and February 2012 using the RAC technique for an abdominal aortic aneurysm. A Simmons-1 catheter was preferred for renal artery cannulation. The mean age of the patients at the time of treatment was 70 years (range, 61–82 years). Fifteen cases were fusiform aneurysms, and one case was a saccular aneurysm. Creatinine and estimated glomerular filtration rate (eGFR) values were recorded before the procedure and during the first 72 hours postprocedure. RESULTSBifurcated stent grafts were implanted with 100% procedural success using the RAC technique. The inferiorly positioned renal artery was cannulated with a Simmons-1 catheter in the first five patients, and was maintained at the level of the renal artery orifice in the remaining patients. The mean volume of the ICM used was 47 mL (range, 23–83 mL). The creatinine and eGFR values were not significantly different between the pre- and postoperative periods (P > 0.05). CONCLUSIONReducing the volume of ICM used during EVAR is critical for protecting renal function. The RAC technique is a safe and effective method in appropriate patients when performed by experienced clinicians.

OBJECTIVE: Assessed the usefulness of virtual cystoscopy performed with multidetector computed tomography (CT) in patients with different urinary bladder pathologies compared to the conventional cystoscopy. MATERIALS AND METHODS: Eighteen patients with different bladder pathologies, which consisted of 11 tumors, 3 diverticula, 2 trabecular changes and 2 stones, were assessed with conventional cystoscopy and virtual CT cystoscopy. The results of virtual CT cystoscopy were compared with the findings of conventional cystoscopy. We determined the detection rate and positive predictive value of CT imaging based virtual cystoscopy in the diagnosis of urinary bladder lesions. RESULTS: CT scanning was well tolerated by all patients, and no complications occurred. Images in 16 (88%) of the 18 virtual cystoscopic examinations were either of excellent or good quality. All tumors except one, 2 trabecular changes and 2 stones were characterized with similar findings in the both of methods. The masses ranged from 0.4 to 7.0 cm in diameter. While conventional cystoscopy could not evaluate interior part of the diverticulum, virtual CT cystoscopy could demonstrate clearly within it. There were no false-positive findings in our series. CONCLUSION: Virtual CT cystoscopy is a promising technique to be used in the detection of bladder lesions. It should be considered especially at the evaluation of bladder diverticula. In the future, it may be possible or even advantageous to incorporate into the imaging algorithm for evaluation of bladder lesion.

Introduction. The limbic system primarily responsible for our emotional life and memories is known to undergo degradation with aging and diffusion tensor imaging (DTI) is capable of revealing the white matter integrity. The aim of this study is to investigate age-related changes of quantitative diffusivity parameters and fiber characteristics on limbic system in healthy volunteers. Methods. 31 healthy subjects aged 25–70 years were examined at 1,5 TMR. Quantitative fiber tracking was performed of fornix, cingulum, and the parahippocampal gyrus. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) measurements of bilateral hippocampus, amygdala, fornix, cingulum, and parahippocampal gyrus were obtained as related components. Results. The FA values of left hippocampus, bilateral parahippocampal gyrus, and fornix showed negative correlations with aging. The ADC values of right amygdala and left cingulum interestingly showed negative relation and the left hippocampus represented positive relation with age. The cingulum showed no correlation. The significant relative changes per decade of age were found in the cingulum and parahippocampal gyrus FA measurements. Conclusion. Our approach shows that aging affects hippocampus, parahippocampus, and fornix significantly but not cingulum. These findings reveal age-related changes of limbic system in normal population that may contribute to future DTI studies.

Underground muon intensities up to 10000 m.w.e. and angular distribution up to 6500 m.w.e. in standard rock have been investigated using Geant4 simulation package. Muons with energies above 100 GeV were distributed from the ground level taking into account the muon charge ratio of ~1.3 at sea level. The simulated differential muon intensities are in good agreement with the intensities given in the literature. Furthermore, the simulation results for the integrated intensities are consistent with the experimental data, particularly at depths above 4000 m.w.e., where the simulation gives slightly smaller intensities than the experimental ones. In addition, the simulated exponent n at different underground depths agrees well with the experimental points, especially above ~2000 m.w.e.

Geant4 simulation package was used to simulate muon fluxes at different locations, the floor of UNIREA mine and two levels of CANTACUZINO mine, of Slanic Prahova site in Romania. This site is specially important since it is one of the seven sites in Europe that are under consideration of housing large detector components of Large Apparatus studying Grand Unification and Neutrino Astrophysics (LAGUNA) project. Simulations were performed for vertical muons and for muons with a zenith angle θ≤60°. Primary muon flux and energies at ground level were obtained from previous measurements. Results of the simulations are in general agreement with previous simulations made using MUSIC simulation program and with the measurements made using a mobile detector.