Birth defects are a major cause of infant mortality and disability in many parts of the world. Yet the etiology of neural tube defects (NTDs), the most common types of birth defects, is still unknown. The construction and analysis of maps of disease incidence data can help explain the geographical distribution of NTDs and can point to possible environmental causes of these birth defects. We com...

Collaborative filtering is an often successful method for personalized item selection in Recommender systems. However, in domains where items are frequently added, collaborative filtering encounters the latency problem. Characterized by the system’s inability to select recently added items, the latency problem appears because new items in a collaborative filtering system must be reviewed before...

social networks play a significant role in today world. these sites affect different aspects of individual and social life of people and the national and even international levels. accordingly, they are spreading, and will play more important role in the future life. this paper aims to examine the positive and negative effects of social networks’ filtering, that creates curiosity and has invers...

spike sorting is a class of techniques used in the analysis of electrophysiological data. studying the dynamics of neural activity via electrical recording relies on the ability to detect and sort neural spikes recorded from a number of neurons by the same electrode. this article reviews methods for detecting and classifying action potentials, a problem commonly referred to as spike sorting.

Objective(s): In order to evaluate the effect of post-reconstruction Gaussian filtering on image quality and myocardial blood flow (MBF) measurement by dynamic N-13 ammonia positron emission tomography (PET), we compared various reconstruction and filtering methods with image characteristics. Methods: Dynamic PET images of three patients with coronary artery disease (male-female ratio of 2:1; a...

background: we investigated whether the lungheart ratio parameter (lhr) can be used to identify the optimum cut off frequency for butterworth filter in 99mtc myocardial spect imaging. materials and methods: this study involved a cardiac phantom system consisting of cardiac insert in which 1.10 cm cold defect was inserted into its myocardium wall and filled with 4.0 μci/ml (0.148 mbq/ml) 99mtc c...

We study a Markov switching stochastic volatility model with heavy tail innovations in the observable process. Due to the economic interpretation of the hidden volatility regimes, these models have many financial applications like asset allocation, option pricing and risk management. The Markov switching process is able to capture clustering effects and jumps in volatility. Heavy tail innovatio...