2,213 research outputs found
Survival probability in Generalized Rosenzweig-Porter random matrix ensemble
We study analytically and numerically the dynamics of the generalized
Rosenzweig-Porter model, which is known to possess three distinct phases:
ergodic, multifractal and localized phases. Our focus is on the survival
probability , the probability of finding the initial state after time
. In particular, if the system is initially prepared in a highly-excited
non-stationary state (wave packet) confined in space and containing a fixed
fraction of all eigenstates, we show that can be used as a dynamical
indicator to distinguish these three phases. Three main aspects are identified
in different phases. The ergodic phase is characterized by the standard
power-law decay of with periodic oscillations in time, surviving in the
thermodynamic limit, with frequency equals to the energy bandwidth of the wave
packet. In multifractal extended phase the survival probability shows an
exponential decay but the decay rate vanishes in the thermodynamic limit in a
non-trivial manner determined by the fractal dimension of wave functions.
Localized phase is characterized by the saturation value of ,
finite in the thermodynamic limit , which approaches
in this limit.Comment: 21 pages, 12 figures, 61 reference
Evasion from many pursuers in simple motion differential game with integral constraints.
We study a two dimensional evasion differential game with several pursuers and one evader with integral constraints on control functions of players. Assuming that the total resource of the pursuers does not exceed that of the evader, we solve the game by presenting explicit strategy for the evader which guarantees evasion
The effect of Fig on antioxidant and oxidative parameter of normal young men in a clinical trial study
Background and aim: Today, due to the increased production of free radicals such as pollution, there is a need to a good antioxidant resource. Fig which is one of the fruit mentioned in the Qur'an, may prevent increased production of free radicals because of its rich content of antioxidants. This study was aimed to study the effect of using figs on oxidant and antioxidant parameters on healthy young men. Materials and methods: In this clinical trial, 74 healthy male students were chosen randomly and divided into two groups of test and control. Age range was 18- 40, and residency in university’s dormitories were entry criteria and disease, smoking and taking other complements were exclude criteria. The test group receive daily 120 g dried fig for four weeks. Blood samples were obtained from two groups at beginning of study and after 4 weeks. Total Antioxidant Capacity (TAC) was measured by FRAP method, activity of GGT and the rate of Fe were matured by auto analyzer system BT 3000. Results: results indicate that Fe level has a significant decrease as an oxidative parameter in the test group (N= 37) after four weeks of interference (p=005/0). GGT and TAC levels showed a significant increase as antioxidant parameters in the test group after four weeks of interference (p= 0/001). Conclusion: Considering the significant decrease in Fe level as the oxidative parameter and substantial increase in GGT and TAC level as the antioxidant parameters, Figs can play an effective and useful role in increasing the antioxidant defend of the body against free radicals and so decrease damages caused by oxidative stress
Rancang Bangun Sistem Informasi Lowongan Kerja di Jpc Polinema dengan Metode Quick Sort
Informasi batas waktu lowongan kerja JPC di Facebook keberadaanya bertumpuk dengan informasi-informasi yang baru. Sehigga sulit untuk menemukan informasi lowongan kerja yang sudah melewati batas waktu dan informasi lowongan kerja yang sesuai dengan kriteria pelamar.Dari permasalahan tersebut maka dibuat aplikasi Lowongan Kerja Di JPC Polinema yang mampu menampilkan informasi lowongan kerja berdasarkan batas waktu dan kriteria pelamar. Metode yang digunakan untuk mensorting semua informasi lowongan kerja yang masuk menggunakan metode Quick Sort. Hasil dari penelitian ini akan menampilkan lowongan kerja setelah melalui sorting dengan batas waktu dan kriteria data pelamar. Kriteria ini terdiri dari 6 kriteria yang berupa gender, jurusan, jenjang, umur, IPK, dan pengalaman kerja
The Study Use Betel Leaves Extract ( Piper Betle ) with Different Concentration of Breaking Strength and Elengation Tetoron Yarn
This research was conducted on March 2015, which is held in the Laboratory of fishing Gear Materials, Utilization of Water Resource, The Faculty of Fisheries and Marine Sciences, University of Riau. The purpose of this research was to determine the effect of the use of preservatives fiber betel leaf extract (Piper betle) with different concentrations of the breaking strength and elengation PES yarn (Polyester). So it can determine the best concentration of the extract. From the measurement of breaking strength tetoron thread that has been getting treatment, the thread tetoron with treatment B (0.7 Kg / Liter of water) has the highest average 5.3 kgf, and followed by treatment of A (0.5 Kg / Liter water), and treatment C (0.9 Kg / Liter of water) with each value of the breaking strength of 5.15 kgf and 5.05 kgf. Tetoron yarn elengation which have been getting treatment, the thread tetoron with treatment B (0.7 Kg / Liter of water) has the highest average is 33.5 mm, and is followed by treatment of A (0.5 Kg / Liter of water) and treatment C (0.9 Kg / Liter of water) with each tetoron yarn elengation are 531.9 mm and 30.2 mm
Improving patient record search: A meta-data based approach
The International Classification of Diseases (ICD) is a type of meta-data found in many Electronic Patient Records. Research to explore the utility of these codes in medical Information Retrieval (IR) applications is new, and many areas of investigation remain, including the question of how reliable the assignment of the codes has been. This paper proposes two uses of the ICD codes in two different contexts of search: Pseudo-Relevance Judgments (PRJ) and Pseudo-Relevance Feedback (PRF). We find that our approach to evaluate the TREC challenge runs using simulated relevance judgments has a positive correlation with the TREC official results, and our proposed technique for performing PRF based on the ICD codes significantly outperforms a traditional PRF approach. The results are found to be consistent over the two years of queries from the TREC medical test collection
The role of gated myocardial perfusion scintigraphy (GMPS) in myocarditis: A case report and review of the literature
Acute myocarditis is one of the most challenging diagnoses and treatments in cardiology. The acute viral myocarditis diagnosis is usually based on high suspicion, history taking, and physical examination. Likewise, the use of chest radiography, electrocardiography (ECG), and echocardiography is helpful in making a final diagnosis, but all are non-specific. In addition, in imaging query, magnetic resonance imaging (MRI) depicts some degree of cardiac inflammation in the course of myocarditis. Myocardial perfusion imaging (MPI) has also been shown to be useful in diagnosis, and this noninvasive technique diminishes the need for myocardial biopsy. The current study presents the diagnostic and prognostic role of MPI in a 25-year-old patient with suspected myocarditis. The patient underwent gated-technetium-99m-lablled, methoxyisobutyl isonitrile, single photon emission computed tomography (Gated 99mTc-MIBI SPECT) that showed nonheterogeneous absorption with remarkable decreased radiotracer uptake in the myocardium in both stress and rest phases. In addition, the gated mode demonstrated decreased wall motion and thickening of the myocardium with a sum motion score (SMS) of 28, a sum thickening score (STS) of 15, and a measured LVEF of 34%. The study concludes that 99mTC-MIBI SPECT imaging is a useful modality in the preparation of supplementary diagnostic and prognostic information in viral myocarditis. Copyright © 2011 Via Medica
The association of rate pressure product (RPP) and myocardial perfusion imaging (MPI) findings: A preliminary study
Introduction: The product of heart rate and systolic blood pressure, termed as rate-pressure product (RPP), is a very reliable indicator of myocardial oxygen demand and is widely used clinically. There have been previous attempts to describe the relationship between RPP and the onset of pain in angina pectoris. The current study aimed to evaluate the association between RPP results and scan findings.Materials and methods: In total, 497 patients with suspected coronary artery disease (CAD) underwent gated, single-photon emission computed tomography (SPECT) imaging with dipyridamole, exercise, or dobutamine stress, and were included in this study. Baseline and maximum heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and electrocardiogram (ECG) results were recorded. The rate-pressure product (RPP) was calculated as the product of heart rate and systolic arterial pressure for both baseline and maximum measures. The difference between the RPP max and the basal RPP is known as the RPP reserve. Researchers also obtained semi-quantitative analyses of myocardial perfusion imaging (MPI), using gated software, demographic information, risk factors of CAD, and pretest likelihoods of CAD using nomograms.Result: Four hundred and ninety-seven cases, including 426 patients with dipyridamole stress, 59 with exercise stress, and 12 with dobutamine stress, underwent myocardial perfusion imaging. Scan results were positive in 194 (45.5) and negative in 232 (54.5) patients with dipyridamole stress. In patients with exercise stress, the scan was positive in 24 (40.7) cases and negative in 35 (59.3) cases. In dobutamine stressed patients, the scan was positive in 6 (50) cases and negative in the 6 remaining cases. Dipyridamole stress resulted in a significant difference between HR at rest and at maximum (28.95 ± 24.53, p-value<0.0001), between systolic BP at rest and maximum (6.75 ± 12.50, p-value<0.0001) and between diastolic BP at rest and maximum (1.45 ± 5.80; p-value<0.0001). There was a significant correlation between sum stress scores (SSS) and reserved RPP (r= -0.12, p-value<0.001) which, in dipyridamole patients, was r=-0.18, p-value=0.0001). In addition, there was a significant association between reserved RPP and risk of CAD (p-value<0.001). In the patients with dipyridamole stress, the ejection fraction (EF) change (odds ratio =0.92; 95 CI: 0.86-0.98; p=0.01), reserve RPP (odds ratio =1.00; 95 CI: 1.00-1.00; p=0.04), risk of CAD (odds ratio =5.80; 95 CI: 3.21-10.50; p<0.0001) and age (odds ratio =0.94; 95 CI: 0.89-0.98; p=0.01) were associated significantly with MPI results, using multiple logistic regressions.Conclusion. The study demonstrated that RPP is associated with MPI findings using gated SPECT imaging with dipyridamole stress. However, to confirm this preliminary result, further studies are mandatory. © The Author(s) 2012
On Bootstrap Percolation in Living Neural Networks
Recent experimental studies of living neural networks reveal that their
global activation induced by electrical stimulation can be explained using the
concept of bootstrap percolation on a directed random network. The experiment
consists in activating externally an initial random fraction of the neurons and
observe the process of firing until its equilibrium. The final portion of
neurons that are active depends in a non linear way on the initial fraction.
The main result of this paper is a theorem which enables us to find the
asymptotic of final proportion of the fired neurons in the case of random
directed graphs with given node degrees as the model for interacting network.
This gives a rigorous mathematical proof of a phenomena observed by physicists
in neural networks
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