79 research outputs found
The Use of Artificial Neural Network for Prediction of Dissolution Kinetics
Colemanite is a preferred boron mineral in industry, such as boric acid production, fabrication of heat resistant glass, and cleaning agents. Dissolution of the mineral is one of the most important processes for these industries. In this study, dissolution of colemanite was examined in water saturated with carbon dioxide solutions. Also, prediction of dissolution rate was determined using artificial neural networks (ANNs) which are based on the multilayered perceptron. Reaction temperature, total pressure, stirring speed, solid/liquid ratio, particle size, and reaction time were selected as input parameters to predict the dissolution rate. Experimental dataset was used to train multilayer perceptron (MLP) networks to allow for prediction of dissolution kinetics. Developing ANNs has provided highly accurate predictions in comparison with an obtained mathematical model used through regression method. We conclude that ANNs may be a preferred alternative approach instead of conventional statistical methods for prediction of boron minerals
Photonuclear reactions with Zinc: A case for clinical linacs
The use of bremsstrahlung photons produced by a linac to induce photonuclear
reactions is wide spread. However, using a clinical linac to produce the
photons is a new concept. We aimed to induce photonuclear reactions on zinc
isotopes and measure the subsequent transition energies and half-lives. For
this purpose, a bremsstrahlung photon beam of 18 MeV endpoint energy produced
by the Philips SLI-25 linac has been used. The subsequent decay has been
measured with a well-shielded single HPGe detector. The results obtained for
transition energies are in good agreement with the literature data and in many
cases surpass these in accuracy. For the half-lives, we are in agreement with
the literature data, but do not achieve their precision. The obtained accuracy
for the transition energies show what is achievable in an experiment such as
ours. We demonstrate the usefulness and benefits of employing clinical linacs
for nuclear physics experiments
Real-world efficacy and safety of Ledipasvir plus Sofosbuvir and Ombitasvir/Paritaprevir/Ritonavir +/- Dasabuvir combination therapies for chronic hepatitis C: A Turkish experience
Background/Aims: This study aimed to evaluate the real-life efficacy and tolerability of direct-acting antiviral treatments for patients with chronic hepatitis C (CHC) with/without cirrhosis in the Turkish population.Material and Methods: A total of 4,352 patients with CHC from 36 different institutions in Turkey were enrolled. They received ledipasvir (LDV) and sofosbuvir (SOF)+/- ribavirin (RBV) ombitasvir/paritaprevir/ritonavir +/- dasabuvir (PrOD)+/- RBV for 12 or 24 weeks. Sustained virologic response (SVR) rates, factors affecting SVR, safety profile, and hepatocellular cancer (HCC) occurrence were analyzed.Results: SVR12 was achieved in 92.8% of the patients (4,040/4,352) according to intention-to-treat and in 98.3% of the patients (4,040/4,108) according to per-protocol analysis. The SVR12 rates were similar between the treatment regimens (97.2%-100%) and genotypes (95.6%-100%). Patients achieving SVR showed a significant decrease in the mean serum alanine transaminase (ALT) levels (50.90 +/- 54.60 U/L to 17.00 +/- 14.50 U/L) and model for end-stage liver disease (MELD) scores (7.51 +/- 4.54 to 7.32 +/- 3.40) (p<0.05). Of the patients, 2 were diagnosed with HCC during the treatment and 14 were diagnosed with HCC 37.0 +/- 16.0 weeks post-treatment. Higher initial MELD score (odds ratio [OR]: 1.92, 95% confidence interval [CI]: 1.22-2.38; p=0.023]), higher hepatitis C virus (HCV) RNA levels (OR: 1.44, 95% CI: 1.31-2.28; p=0.038), and higher serum ALT levels (OR: 1.38, 95% CI: 1.21-1.83; p=0.042) were associated with poor SVR12. The most common adverse events were fatigue (12.6%), pruritis (7.3%), increased serum ALT (4.7%) and bilirubin (3.8%) levels, and anemia (3.1%).Conclusion: LDV/SOF or PrOD +/- RBV were effective and tolerable treatments for patients with CHC and with or without advanced liver disease before and after liver transplantation. Although HCV eradication improves the liver function, there is a risk of developing HCC.Turkish Association for the Study of The Liver (TASL
The Confidence Database
Understanding how people rate their confidence is critical for the characterization of a wide range of perceptual, memory, motor and cognitive processes. To enable the continued exploration of these processes, we created a large database of confidence studies spanning a broad set of paradigms, participant populations and fields of study. The data from each study are structured in a common, easy-to-use format that can be easily imported and analysed using multiple software packages. Each dataset is accompanied by an explanation regarding the nature of the collected data. At the time of publication, the Confidence Database (which is available at https://osf.io/s46pr/) contained 145 datasets with data from more than 8,700 participants and almost 4 million trials. The database will remain open for new submissions indefinitely and is expected to continue to grow. Here we show the usefulness of this large collection of datasets in four different analyses that provide precise estimations of several foundational confidence-related effects
Complete atrioventricular block in a child with normal cardiac functions
Complete atrioventricular block is a rare complication in noncardiac operations of children, though it is life threatening. Complete atrioventicular block may occur secondary to many causes and it does not response to medical treatments. An 11 years-old girl was brought to our hospital with fever and abdominal pain finally diagnosed as acute appendicitis. Anamnesis, physical examination, laboratory findings and radiological findings were found to be normal. After anesthesia induction, the mask ventilation has been applied. Intubation was performed after giving muscle relaxants. After first surgical incision multiple arrhythmias were monitored. Cardiac arrhythmias continue long time and complete A-V block developed. Arrhythmias did not respond to medical treatment. The patient showed no hemodynamic instability and she awakened after completion of surgical operation. She was sent to intensive care unit because of complete A-V block. Pacemaker was not applied because of not having any symptom. A patient who was diagnosed as congenital complete AV block has been followed up with regular intervals
Comparison of the calcaneal pitch angle and modified projection area per length squared method for medial longitudinal arch evaluation of the foot.
OBJECTIVE: To compare the calcaneal pitch angle (CPA) values measured on direct lateral radiographs of feet, and the modified projection area per length squared (PAL), which was calculated as a new method for the evaluation of the medial longitudinal arch (MLA) of the foot. MATERIAL AND METHODS: Direct lateral radiographs of patients who had weightbearing feet radiographies for any reason except trauma were retrospectively obtained from the archives. Direct lateral radiographs of the feet were printed and a transparent sheet was placed on it. A straight line was drawn between the most plantar process of the calcaneus and the head of the first metatarsal bone for the calculation of the PAL of the MLA. Two semilunar arcs were drawn upon this straight line. PAL1 and PAL2 were estimated using a point-counting technique. The CPA, lateral talo-calcaneal angles (LTCA), and talo-first metatarsal angles (TFMA) were measured. The correlations between PAL1, PAL2 of right and left feet and CPA, LTCA, and TFMA were explored. RESULTS: Fifty patients (27 females, 23 males) with a mean age of 40.12 (4-78) years were evaluated. Significant correlations were detected between PAL1, PAL2 and CPA, and TFMA for both right and left feet (p<0.05). CONCLUSION: A significant correlation was detected between the modified PAL method as a new technique and the standard CPA method for MLA evaluation. The PAL method is suggested as a simple and practical method for MLA evaluation
Do learning approaches of medical students affect their satisfaction with problem-based learning?
The aim of this research was to determine the satisfaction of medical students with problem-based learning (PBL) and their approaches to learning to investigate the effect of learning approaches on their levels of satisfaction. The study group was composed of medical students from three different universities, which apply PBL at different levels in their curricula. The revised two-factor study process survey was applied to the study group to determine their approaches to learning as "deep" or "surface" learning. In addition, another survey of 20 questions was used to determine satisfaction levels of students with PBL and other variables. Of the study group, 64.6% were found to adopt a deep approach to learning, and we confirmed that these students were reasonably more satisfied with PBL. © 2013 the American Physiological Society
Ultra-fast curve fitting for pulses on FPGA
Due to copyright restrictions, the access to the full text of this article is only available via subscription.Bu çalışmada anlatılan donanım 1.5 GHz Analog-Sayısal- Çevirici’den gelen darbe işaret dizisini işleyebilmekte ve darbe işaretlerini genlik, yükselme/düşme süresi ve varış zamanı parametreleriyle özetleyebilmektedir. Söz konusu donanım arka arkaya gelen sıfır ölü-süreli darbe işaretlerini işleyebilmektedir. Darbeler 9 örnek kadar kısa olabilmektedir. Bu şekildeki darbe işaretleri (ve hatta birçok kanallı olanları) parçacıkların hızlandırılıp, çarpıştırılıp ve algılandıkları yüksek enerji fizik deneylerinde bulunmaktadır. Benzer fiziksel kurulumlar nükleer tıp imgelemede, özellikle Pozitron Salımı Tomografisi’nde de mevcuttur. Donanım gerçeklemesini Sahada Programlanabilir Kapı Dizileri (FPGA) üzerinde yaptık. FPGA’lar yüksek düzeyde paralellik ve bunun sonucu yüksek veri işleme gücü sunmaktadırlar. Bu bildiride, üst seviye mimari, ara yapı detayları, tasarım süreci ve gerçekleme detayları sunulmaktadır. FPGA tasarımımız sayesinde ilgili uygulamalarda alan, güç, devreye alınma zamanı ve operasyonel maliyet tasarrufu sağlamak mümkündür.TÜBİTA
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