Neoteric Hybrid Multilevel Cascade Inverter Based on Low Switch Numbers Along with Low Voltage Stress: Design, Analysis, Verification

Abstract: With the purpose of rein in the high voltage of flexible power systems, renovation and amendment of multi-level structures aimed at acquisition of high quality voltage is certainly required. In this regard, robust topology must be occupied that encompass the maximum output voltage levels along with minimum of switch number, of course, with taking into account of Peak Inverse Voltage (PIV). In this paper, a neoteric high-performance multilevel cascaded inverter is suggested up to the problem of repetitive output levels to be unraveled and also number of output voltage levels to be maximized. It has been constructed by series-connected multilevel inverters blocks and three-level inverter. The simulation results along with experimental results extracted by manufactured prototype have transparently approved high efficiency of proposed inverter as well as its feasibility. Apart from above, new mathematical approach has been presented to calculate and define the DC voltage sources magnitudes in asymmetric converter

The first record of bobtail squid, Euprymna hyllebergi Nateewathana, 1997 (Cephalopoda:Sepiolidae) from the Persian Gulf, Iran

The family Sepiolidae comprises over 50 species in 14 genera. They are commonly known as bobtail squids with a worldwide distribution from tropical to temperate and sub-polar latitudes of all oceans (Nateewathana, 1997; Aungtonya et al., 2011). Euprymna hyllebergi belongs to the Sepiolidae family and Sepiolinae subfamily. This species has a wide distribution in the Eastern Indian Ocean, and has been recorded up to the depth of 47 meters in Andaman Sea, Thailand (Jereb and Roper, 2005). The family Sepiolidae, includes all bobtail squids with kidney-shape fins. Little is known about their biology, but they are common in tropical, temperate and sub polar waters of all oceans (Jereb and Roper, 2010). This is the first record of the bobtail squid, E. hyllebergi from the Persian Gulf. On 27th of March 2013 during a scuba diving session in Persian Gulf (Figure 1, coordinates: 54° 49’39.5”E, 26° 26’ 55.3”N) about 200 eggs of E. hyllebergi were collected at the depth of 40 meters in northern Persian Gulf. The eggs (Fig. 2a) were transferred to the Persian Gulf Shellfishes Research Center laboratory for further incubation and hatching

A numerical method for solving nonlinear integral equations

Abstract Integral equations occur naturally in many field of mechanics and mathematical physics. In this paper, an iterative scheme based on the homotopy analysis method (HAM) has been used for solving one of the most important cases in nonlinear integral equations which is called urysohn form. For this scope, we applied some examples with known exact solutions and the numerical solutions obtained confirm that the method is very effective and simple. Also, show the advantage of this method, the results obtained by (HAM) are compared with NewtonKantorovich-quadrature method. Convergence is also observed

Effectiveness of Ledipasvir/Sofosbuvir with/without Ribavarin in Liver Transplant Recipients with Hepatitis C.

Background and Aims: Recurrent infection of hepatitis C virus (HCV) in liver transplant (LT) recipients is universal and associated with significant morbidity and mortality. Methods: We retrospectively evaluated the safety and efficacy of ledipasvir/sofosbuvir with and without ribavirin in LT recipients with recurrent genotype 1 hepatitis C. Results: Eighty-five LT recipients were treated for recurrent HCV with ledipasvir/sofosbuvirwith and without ribavirin for 12 or 24 weeks. The mean (± standard deviation [SD]) time from LT to treatment initiation was 68 (±71) months. The mean (± SD) age of the cohort was 63 (±8.6) years old. Most recipients were male (70%). Baseline alanine transaminase, total bilirubin, and HCV ribonucleic acid (RNA) values (± SD) were 76.8 (±126) mg/dL, 0.8 (±1.3) U/L, and 8,010,421.9 (±12,420,985) IU/mL, respectively. Five of 43 recipients who were treated with ribavirin required drug cessation due to side effects, with 4 of those being anemia complications. No recipient discontinued the ledipasvir/sofosbuvir. Eighty-one percent of recipients had undetectable viral levels at 4 weeks after starting therapy, and all recipients had complete viral suppression at the end of therapy. The sustained viral response at 12 weeks after completion of therapy was 94%. Conclusion : Ledipasvir and sofosbuvir with and without ribavirin therapy is an effective and well-tolerated interferon-free treatment for recurrent HCV infection after LT. Anemia is not uncommon in LT recipients receiving ribavirin

IMECE2008-66292 EXPERIMENTAL ANALYSIS OF VIBRATION OF MICROMACHINED RESONATORS

ABSTRACT Among many different mechanisms that are used for excitation and detection of vibration of micro-beam resonators, electrostatic comb-drives have the benefit of simplicity and large range of linear operation. The disadvantage of using comb-drives is the effect of added mass to the beam; however, the analytical model of the beam-mass system predicts that this shortcoming can be overcome by proper adjustment of the mass, rotary inertia, and location of the comb-drive. In addition, the analytical model can predict the effect of the axial force of the beam on the resonance frequencies. In this paper, the results of the experiments on two resonators are presented. These results are used to verify the validity of the analytical model and finding its parameters. Very close agreement between the theory and experiment is observed. The residual stress of the MEMS structural layer is measured using the calibrated analytical model parameters

Oesophageal cancer among the Turkomans of northeast Iran

A Caspian Littoral Cancer Registry survey in the early 1970s established northern Iran as one of the highest oesophageal cancer incidence regions of the world. To verify this, an oesophageal cancer survey was carried out between 1995 and 1997 in the Turkoman Plain at the southeastern corner of the Caspian Sea. Oesophageal balloon cytology screening was carried out on 4192 asymptomatic adults above age 30 years in one town and three adjoining villages with a total population of 20 392 people at risk. Oesophagoscopy was performed on 183 patients with abnormal cytological findings. The discovery of two asymptomatic small squamous cell cancers and one ‘carcinoma- suspect’ implied a prevalence ranging from 47.7 per 100 000 to 71.5 per 100 000. During a 1-year active surveillance, 14 patients were found with clinically advanced oesophageal squamous cell cancer, yielding age-standardized incidence rates of 144.09 per 100 000 for men and 48.82 per 100 000 for women. The very high frequency of oesophageal cancer reported for northern Iran 25 years ago stands confirmed. Differences in incidence rates, then and now, can be attributed to survey methods used and diagnostic criteria applied, but not to socioeconomic factors, which have remained relatively stable. Oesophageal balloon cytology is a practical method of mass screening for oesophageal cancer in Iran. © 2000 Cancer Research Campaig

Big Bang Nucleosynthesis Constraints on Primordial Magnetic Fields

We reanalyze the effect of magnetic fields in BBN, incorporating several features which were omitted in previous analyses. We find that the effects of coherent magnetic fields on the weak interaction rates and the electron thermodynamic functions (\rhoe, \Pe, and \drhoedt ) are unimportant in comparison to the contribution of the magnetic field energy density in BBN. In consequence the effect of including magnetic fields in BBN is well approximated numerically by treating the additional energy density as effective neutrino number. A conservative upper bound on the primordial magnetic field, parameterized as $\zeta=2eB_{rms}/(T_\nu^2)$, is $\zeta \le 2$ ($\rho_B < 0.27 \rho_\nu$). This bound can be stronger than the conventional bound coming from the Faraday rotation measures of distant quasars if the cosmological magnetic field is generated by a causal mechanism.Comment: Latex, 20 pages, 3 uuencoded figures appende

Testing The Friedmann Equation: The Expansion of the Universe During Big-Bang Nucleosynthesis

In conventional general relativity, the expansion rate H of a Robertson-Walker universe is related to the energy density by the Friedmann equation. Aside from the present day, the only epoch at which we can constrain the expansion history in a model-independent way is during Big-Bang Nucleosynthesis (BBN). We consider a simple two-parameter characterization of the behavior of H during BBN and derive constraints on this parameter space, finding that the allowed region of parameter space is essentially one-dimensional. We also study the effects of a large neutrino asymmetry within this framework. Our results provide a simple way to compare an alternative cosmology to the observational requirement of matching the primordial abundances of the light elements.Comment: 18 pages, Final version to be published in Phys. Rev.

Multiple solutions and corresponding power output of a nonlinear bistable piezoelectric energy harvester

We examine multiple responses of a vibrational energy harvester composed of a vertical beam and a tip mass. The beam is excited horizontally by a harmonic inertial force while mechanical vibrational energy is converted to electrical power through a piezoelectric patch. The mechanical resonator can be described by single or double well potentials depending on the gravity force from the tip mass. By changing the tip mass we examine the appearance of various solutions and their basins of attraction. Identification of particular solutions of the energy harvester is important as each solution may provide a different level of power output