Montgomery and RNS for RSA Hardware Implementation

There are many architectures for RSA hardware implementation which improve its performance. Two main methods for this purpose are Montgomery and RNS. These are fast methods to convert plaintext to ciphertext in RSA algorithm with hardware implementation. RNS is faster than Montgomery but it uses more area. The goal of this paper is to compare these two methods based on the speed and on the used area. For this purpose the architecture that has a better performance for each method is selected, and some modification is done to enhance their performance. This comparison can be used to select the proper method for hardware implementation in both FPGA and ASIC design

Cryptanalysis with Ternary Difference: Applied to Block Cipher PRESENT

Signed difference approach was first introduced by Wang for finding collision in MD5. In this paper we introduce ternary difference approach and present it in 3 symbols. To show its application we combine ternary difference approach with conventional differential cryptanalysis and apply that to cryptanalysis the reduced round PRESENT. We also use ant colony technique to obtain the best differential characteristic. To illustrate the privilege in the result of experiment, we calculate advantage of the attack

An Efficient Protocol for Oblivious DFA Evaluation and Applications

In this paper, we design an efficient protocol for \emph{oblivious DFA evaluation} between an input holder (client) and a DFA holder (server). The protocol runs in a single round, and only requires a small amount of computation by each party. The most efficient version of our protocol only requires $O(k)$ asymmetric operations by either party, where $k$ is the security parameter. Moreover, the client\u27s total computation is only linear in his own input and independent of the size of the DFA. We prove the protocol fully-secure against a \emph{malicious client} and \emph{private} against a malicious server, using the standard \emph{simulation-based} security definitions for secure two-party computation. We show how to transform our construction in order to solve multiple variants of the \emph{secure pattern matching} problem without any computational overhead. The more challenging variant is when parties want to compute the number of occurrences of a pattern in a text (but nothing else). We observe that, for this variant, we need a protocol for counting the number of accepting states visited during the evaluation of a DFA on an input. We then introduce a novel modification to our original protocol in order to solve the counting variant, without any loss in efficiency or security. Finally, we fully implement our protocol and run a series of experiments on a client/server network environment. Our experimental results demonstrate the efficiency of our proposed protocol and, confirm the particularly low computation overhead of the client

Association of Exposure to Fine Particulate Matter and Risk Factors of Non-Communicable Diseases in Children and Adolescents

Background: Risk factors of non-communicable disease (NCD) origin from early life, and exposure to environmental pollutant may be a predisposing factor. This study aimed to investigate the association of air quality index (AQI) and fine particulate matter (PM2.5) with some NCD risk factors in a sample of Iranian children and adolescents. Materials and Methods: This cross-sectional study was conducted in 2014 to 2016 among children and adolescents, aged 6-18 years, in Isfahan, Iran. Physical examination, including weight, height, and blood pressure, was conducted by standard methods. Fasting blood sample was obtained for fasting blood glucose, total cholesterol, high density lipoprotein-cholesterol, low-density lipoprotein- cholesterol, and triglycerides. The mean AQI and PM2.5 values from the study time till one year prior to the survey were used. Multiple linear regression analysis was conducted for the association of AQI and PM2.5 with other variables. Results: Participants consisted of 186 children and adolescents with mean (SD) age of 10.52(2.38) years. Exposure to higher level of PM2.5 had significant associations with higher levels of systolic blood pressure, low-density lipoprotein cholesterol, and triglycerides. It also had positive relationship with other risk factors and inverse association with low-density lipoprotein cholesterol (LDL-C), but these associations were not statistically significant. The corresponding figures were not significant for AQI. Conclusion: At current study results showed that exposure to higher levels of fine particulates was associated with some NCD risk factors in children and adolescents. Early life prevention of NCDs can lead to large reductions in disease risk; adverse effects of ambient pollutants should be considered in this regard

The Carter Constant for Inclined Orbits About a Massive Kerr Black Hole: near-circular, near-polar orbits

In an extreme mass-ratio binary black hole system, a non-equatorial orbit will list (i.e. increase its angle of inclination, {\iota}) as it evolves in Kerr spacetime. The abutment, a set of evolving, near-polar, retrograde orbits, for which the instantaneous Carter constant (Q) is at its maximum value (Q_{X}) for given values of latus rectum (l) and eccentricity (e), has been introduced as a laboratory in which the consistency of dQ/dt with corresponding evolution equations for dl/dt and de/dt might be tested independently of a specific radiation back-reaction model. To demonstrate the use of the abutment as such a laboratory, a derivation of dQ/dt, based only on published formulae for dl/dt and de/dt, was performed for elliptical orbits on the abutment. The resulting expression for dQ/dt matched the published result to the second order in e. We believe the abutment is a potentially useful tool for improving the accuracy of evolution equations to higher orders of e and l^{1}.Comment: 35 Pages, 1 figure, Accepted for publication in Cent Eur J Phy

First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

The relationship of air pollution and surrogate markers of endothelial dysfunction in a population-based sample of children

<p>Abstract</p> <p>Background</p> <p>This study aimed to assess the relationship of air pollution and plasma surrogate markers of endothelial dysfunction in the pediatric age group.</p> <p>Methods</p> <p>This cross-sectional study was conducted in 2009-2010 among 125 participants aged 10-18 years. They were randomly selected from different areas of Isfahan city, the second large and air-polluted city in Iran. The association of air pollutants' levels with serum thrombomodulin (TM) and tissue factor (TF) was determined after adjustment for age, gender, anthropometric measures, dietary and physical activity habits.</p> <p>Results</p> <p>Data of 118 participants was complete and was analyzed. The mean age was 12.79 (2.35) years. The mean pollution standards index (PSI) value was at moderate level, the mean particular matter measuring up to 10 μm (PM₁₀) was more than twice the normal level. Multiple linear regression analysis showed that TF had significant relationship with all air pollutants except than carbon monoxide, and TM had significant inverse relationship with ozone. The odds ratio of elevated TF was significantly higher in the upper vs. the lowest quartiles of PM₁₀, ozone and PSI. The corresponding figures were in opposite direction for TM.</p> <p>Conclusions</p> <p>The relationship of air pollutants with endothelial dysfunction and pro-coagulant state can be an important factor in the development of atherosclerosis from early life. This finding should be confirmed in future longitudinal studies. Concerns about the harmful effects of air pollution on children's health should be considered a top priority for public health policy; it should be underscored in primordial and primary prevention of chronic diseases.</p

Sensitivity of the Advanced LIGO detectors at the beginning of gravitational wave astronomy

The Laser Interferometer Gravitational Wave Observatory (LIGO) consists of two widely separated 4 km laser interferometers designed to detect gravitational waves from distant astrophysical sources in the frequency range from 10 Hz to 10 kHz. The first observation run of the Advanced LIGO detectors started in September 2015 and ended in January 2016. A strain sensitivity of better than 10−23/Hz−−−√ was achieved around 100 Hz. Understanding both the fundamental and the technical noise sources was critical for increasing the astrophysical strain sensitivity. The average distance at which coalescing binary black hole systems with individual masses of 30  M⊙ could be detected above a signal-to-noise ratio (SNR) of 8 was 1.3 Gpc, and the range for binary neutron star inspirals was about 75 Mpc. With respect to the initial detectors, the observable volume of the Universe increased by a factor 69 and 43, respectively. These improvements helped Advanced LIGO to detect the gravitational wave signal from the binary black hole coalescence, known as GW150914

Search for post-merger gravitational waves from the remnant of the binary neutron star merger GW170817

In Advanced LIGO, detection and astrophysical source parameter estimation of the binary black hole merger GW150914 requires a calibrated estimate of the gravitational-wave strain sensed by the detectors. Producing an estimate from each detector's differential arm length control loop readout signals requires applying time domain filters, which are designed from a frequency domain model of the detector's gravitational-wave response. The gravitational-wave response model is determined by the detector's opto-mechanical response and the properties of its feedback control system. The measurements used to validate the model and characterize its uncertainty are derived primarily from a dedicated photon radiation pressure actuator, with cross-checks provided by optical and radio frequency references. We describe how the gravitational-wave readout signal is calibrated into equivalent gravitational-wave-induced strain and how the statistical uncertainties and systematic errors are assessed. Detector data collected over 38 calendar days, from September 12 to October 20, 2015, contain the event GW150914 and approximately 16 of coincident data used to estimate the event false alarm probability. The calibration uncertainty is less than 10% in magnitude and 10 degrees in phase across the relevant frequency band 20 Hz to 1 kHz