Radiative deformation

An infinitesimal change δQδQ in heat flux Q is shown, in terms of entropy flux Ψ=Q/T,Ψ=Q/T, to have two parts, δQ=TδΨ+ΨδT.δQ=TδΨ+ΨδT. The first part being the thermal displacement and the second part being the thermal deformation. Only the second part dissipates into internal energy and generates entropy. Thermodynamic arguments are extended to transport phenomena. It is shown that the thermal part of the rate of local entropy generation is related to the local rate of thermal deformation by s′′′=−ψi/T(∂T/∂xi),s′′′=−ψi/T(∂T/∂xi), where ψi=qi/T,ψi=qi/T, ψiψi being the rate of entropy flux vector, and qiqi the rate of heat flux vector. The part of this generation related to radiation is illustrated in terms of an example. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70807/2/JAPIAU-87-6-3093-1.pd

Numerical investigations of planar solidification of an undercooled liquid

We investigate evolution of a planar interface during unstable solidification of a pure undercooled liquid between two parallel plates. The governing equations are solved using a front tracking/finite difference technique that allows discontinuous material properties between the phases and interfacial anisotropy. The simulations produce some of the futures of the dendritic solidification which are in good qualitative agreement with the works of the previous investigators. The effects of the physical parameters on the crystal growth and interface instability are also examined. © 1997 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87387/2/629_1.pd

On interface dynamics

An intuitive study is presented for unstable interfacial waves. The maximum wavelength obtained for the most rapid unstable growth is shown to have a universal part which also characterizes the isotropic scales of buoyancy-driven turbulence. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70336/2/PHFLE6-12-5-1244-1.pd

Challenges in commercialization of nano and biotechnologies in agricultural sector of Iran

The major purpose of this study was to determine challenges in commercialization of nano and biotechnologies in agicultural sector of Iran. The total population for this study was 50 participants who attended a workshop on commercialization of nano and biotechnologies in agriculture at biotech 2010 exhibition in Tehran. The results showed that the social and cultural challenges caused 39% of variance on the perception of the respondents about challenges influencing the commercialization of nano and biotechnologies in agricultural sector of Iran. The commercialization of nano and biotechnologies in Iran faces challenges and obstacles and require location-specific approaches.Key words: Commercialization, challenges, agriculture sector, Iran, nanotechnologies, biotechnologie

Optic nerve sonography in the diagnostic evaluation of pseudopapilledema and raised intracranial pressure: A cross-sectional study

Introduction. Differentiating pseudopapilledema from papilledema which is optic disk edema and a result of increased ICP (intracranial pressure) is important and can be done with noninvasive methods like orbital ultrasound examination. Method. This was a cross-sectional study in which patients with optic nerve head swelling were referred for LP exam after optic nerve head swelling diagnosis confirmation and having normal brain imaging (CT scan). Before LP (lumbar puncture) exam the patients were referred for optic nerve ultrasound test of both eyes. Results. Considering 5.7 mm as the upper limit for normal ONSD (optic nerve sheath diameter), sensitivity and negative predictive value of optic sonography in diagnosis of pseudopapilledema are 100 for both eyes. Calculated accuracy validity of ONSD measurement in detecting pseudopapilledema is 90 for the right eye and 87 for the left eye. Conclusion. Our study demonstrated a close correlation between optic nerve sheath dilation on ocular ultrasound and evidence of elevated ICP with optic disk swelling. With the aid of noninvasive diagnostic tests we can avoid unnecessary concerns along with expensive and invasive neurological investigations while targeting the correct diagnosis in bilateral optic disk swelling. Our study showed optic nerve sonography as a reliable diagnostic method for further usage. © 2015 Masoud Mehrpour et al

Simulations of a weakly conducting droplet under the influence of an alternating electric field

We investigate the electrohydrodynamics of an initially spherical droplet under the influence of an external alternating electric field by conducting axisymmetric numerical simulations using a charge-conservative volume-of-fluid based finite volume flow solver. The mean amplitude of shape oscillations of a droplet subjected to an alternating electric field for leaky dielectric fluids is the same as the steady-state deformation under an equivalent root mean squared direct electric field for all possible electrical conductivity ratio $(K_r)$ and permittivity ratio $(S)$ of the droplet to the surrounding fluid. In contrast, our simulations for weakly conducting media show that this equivalence between alternating and direct electric fields does not hold for $K_r \ne S$. Moreover, for a range of parameters, the deformation obtained using the alternating and direct electric fields is qualitatively different, i.e. for low $K_r$ and high $S$, the droplet becomes prolate under alternating electric field but deforms to an oblate shape in the case of the equivalent direct electric field. A parametric study is conducted by varying the time period of the applied alternating electric field, the permittivity and the electrical conductivity ratios. It is observed that while increasing $K_r$ has a negligible effect on the deformation dynamics of the droplet for $K_r<S$, it enhances the deformation of the droplet when $K_r>S$ for both alternating and direct electric fields. We believe that our results may be of immense consequence in explaining the morphological evolution of droplets in a plethora of scenarios ranging from nature to biology.Comment: 10 pages, 8 figure

Comparing efficacy of montelukast versus doxycycline in treatment of moderate acne

Background: Treatment of acne is an important issue for reducing the cosmetic and psychological burden of disease. Regarding the inflammatory effect of LT-B4 in acne lesions and action mechanism of Montelukast, this study was performed to determine the efficacy of Montelukastin acne treatment comparison with doxycycline. Materials and Methods: In a randomized clinical trial that was performed in Dermatology Clinic in a Training Tertiary Health Care Center in Tehran, Iran since January 2012 to May 2014, 52 patients with moderate acne were evaluated. The included patients were randomly assigned to receive doxycycline 100 mg/day plus 1 Clindamycin solution (Group 1) or Montelukast 5 mg daily plus 1 clindamycin solution (Group 2). The acne severity index was measured and compared between two groups at baseline (on admission), 1-month and 3 months later. Independent-Sample-T, Chi-Square, and Repeated-Measure ANOVA tests were used and were considered statistically significant at P < 0.05. Results: The mean age was 26.8 ± 7.1 in Group 1 and25 ± 4.8 in Group 2 (P = 0.1). 73 women and 26.7 4 men in Group 1 and 86.7 women, and 13.3 men in Group 2 (P = 0.01). The mean acne severity index at baseline was 18.2 ± 6.1 and 19 ± 4.2 in Montelukast and doxycycline group, respectively (P = 0.679). The mean acne severity index after 1-month was 10.5 ± 6.2 and 12.9 ± 3.3 in Montelukast and doxycycline group, respectively (P = 0). Finally, the mean acne severity index after 3 months follow-up was 8.6 ± 4.8 and 8.2 ± 1.2 in Montelukast and doxycycline group, respectively (P = 0.01). There was no significant difference between two groups regarding the amount of decrease in acne severity index across the study (P = 0.186). However, each groups showed a significant reduction in the acne severity index, separately (P = 0.001). Conclusion: It may be concluded that Montelukast is an effective and safe medication for moderate-level acne treatment. © 2015, Isfahan University of Medical Sciences(IUMS). All rights reserved

Concrete Patching Materials and Techniques and Guidelines for Hot Weather Concreting

High early strength (HES) concrete is becoming increasingly used to repair damaged concrete pavement sections. The use of HES concrete enables the repaired pavement to be opened to traffic within hours of placing the concrete. Rapid repair of concrete pavement is an attractive solution since the traveling public is not delayed by the repair of the pavement in addition to a decrease in the amount of exposure to traffic by construction personnel; however, there are challenges due to strict requirements for opening strength and severe penalties for not achieving the target strength. This project examined failure to obtain long term strength in the construction practices of long patches in concrete pavements. The work examined issues associated with temperature on sulfate balance, flexural strength prediction (maturity methods) considering the influence of moisture (effects of self-desiccation), shrinkage mitigation techniques (internal curing), and improving the overall durability of HES concrete patching materials

A combination of GFRP sheets and steel cage for seismic strengthening of shear-deficient corner RC beam-column joints

International Institute of Earthquake Engineering and Seismology (IEES), project number 7342

A combination of GFRP sheets and steel cage for seismic strengthening of shear-deficient corner RC beam-column joints

International Institute of Earthquake Engineering and Seismology (IEES), project number 7342