Constructing warm inflationary model in brane-antibrane system

Recently, various observational data predict a possibility that inflation may naturally occur in a warm region. In this scenario, radiation is produced during the inflation epoch and reheating is avoided. The main question arises that what is the origin of warm inflation in 4D universe? We answer to this question in brane-antibrane system. We propose a model that allows all cosmological parameters like the scale factor a, the Hubble parameter H and phantom energy density depend on the equation of state parameter in transverse dimension between two branes. Thus, an enhancement in these parameters can be a signature of some evolutions in extra dimension. In our model, the expansion of 4D universe is controlled by the separation distance between branes and evolves from non-phantom phase to phantom one. Consequently, phantom-dominated era of the universe accelerates and ends up in big-rip singularity. Also, we show that as the tachyon potential increases, the effect of interaction between branes on the 4D universe expansion becomes systematically more effective, because at higher energies there exists more channels for flowing energy from extra dimension to other four dimensions. Finally, we test our model against WMAP and Planck data and obtain the ripping time. According to experimental data, $N\simeq 50$ case leads to $n_{s}\simeq 0.96$, where \emph{N} and $n_{s}$ are the number e-folds and the spectral index respectively. This standard case may be found in $0.01 < R_{Tensor-scalar } < 0.22$, where $R_{Tensor-scalar }$ is the tensor-scalar ratio. At this point, the finite time that Big Rip singularity occurs is $t_{rip}=33(Gyr)$.Comment: 16 pages, 3 figures, Accepted in Phys. Lett. B. arXiv admin note: text overlap with arXiv:0708.3233 by other author

Hidden Conformal Symmetry of Kerr-Bolt Spacetimes

We extend the recent proposal of hidden conformal symmetry to the four-dimensional spacetimes with rotational parameter and NUT twist. We consider the wave equation of a massless scalar field in background of Kerr-Bolt spacetimes and show in the "near region", the wave equation can be reproduced by the $SL(2,R)_L \times SL(2,R)_R$ Casimir quadratic operators. Moreover, we compute the microscopic entropy of the dual CFT by Cardy formula and find a perfect match to Bekenstein-Hawking entropy of Kerr-Bolt spacetimes. The absorption cross section of a near region scalar field also matches to microscopic absorption cross section of the dual CFT.Comment: 9 pages, re-organized and re-writtend, typos corrected, main results and conclusion unchange

Real-time Measurement of Stress and Damage Evolution During Initial Lithiation of Crystalline Silicon

Crystalline to amorphous phase transformation during initial lithiation in (100) silicon-wafers is studied in an electrochemical cell with lithium metal as the counter and reference electrode. It is demonstrated that severe stress jumps across the phase boundary lead to fracture and damage, which is an essential consideration in designing silicon based anodes for lithium ion batteries. During initial lithiation, a moving phase boundary advances into the wafer starting from the surface facing the lithium electrode, transforming crystalline silicon into amorphous LixSi. The resulting biaxial compressive stress in the amorphous layer is measured in situ and it was observed to be ca. 0.5 GPa. HRTEM images reveal that the crystalline-amorphous phase boundary is very sharp, with a thickness of ~ 1 nm. Upon delithiation, the stress rapidly reverses, becomes tensile and the amorphous layer begins to deform plastically at around 0.5 GPa. With continued delithiation, the yield stress increases in magnitude, culminating in sudden fracture of the amorphous layer into micro-fragments and the cracks extend into the underlying crystalline silicon.Comment: 12 pages, 5 figure

The comparison of growth rate, survival and food conversion ratio in Penaeus semisulcatus and Fenneropenaeus indicus in Helleh site, Bushehr province

Growth rate, survival and food conversion ratio were compared for two species of shrimp Penaeus semisulcatus and Fenneropenaeus indicus in Bushehr Province in summer 2002. The research was done with two treatments each in three replications in 0.4 ha ponds. Twenty five post larvae of the shrimps in stage PL ^ (12) with a mean weight of 5mg were stocked per square meter of the ponds and cultured for 109 days. We found significant differences during the first 31 days in SGR between P. semisulcatus and F. indicus (P<0.05). The mean final harvest rate was 903.33kg and 1025.00kg in each pond for P. semisulcatus and F. indicus, respectively. No significant differences in physical and chemical parameters were observed between the two species

Determination spawning season and changes in reproduction cycle of Schizothorax zarudnyi and condition factor in Hamoon Lake

Schizothorax zarndnyi is one of the most economic and endemic species, which are found in rivers and triple lagoons of Hamoon. In this study, reproduction cycle, type, season and optimum temperature of spawning period was studied from July 1998 to June 1999. The maximum GSI was 7.9-9.6 in March and April with 14-18°C mean temperatures. The minimum GSI was 0.92 in May. Variation in GSI values shows that reproduction has annual cycle which begins in May and ends in April of the next year. From October significant increase of oocyte diameter and GSI were observed in 2 different groups, while oocyte distribution observed only in one group in May. The rate of HSI had flucatuation, during resting period of ovule (from May to September) and from October simultaneously with significant increase of GSI, the HSI increased and continued to January and decreased in March and April. The condition factor, was changed during reproduction cycle and it was minimum in March (0.92). Concerning these investigation, Sch. zarndnyi is a total spawner and showing a synchronous ovary

Accessibility to the public facilities: A mean to achieve civil rights of the people with disabilities in Iran

Objective: Civil rights may cover different aspects of citizens' lives. All the members of the society should have equal access to the public facilities and public transportation system. Barriers and obstacles in society may limit the accessibility of these facilities to the disabled people. Method: This article contains a part of the results in a phenomenological study of the Disability Rights. The purpose of this phenomenological study was to describe experiences of disability rights among 11 physically disabled that were living in Tehran, Iran. The study involves secondary analysis of in-depth transcribed interview data, using colazzi's method. Results:A total of 655 descriptive expressions were categorized in to 25 preliminary structural elements (sub themes). 7 essential structural elements (themes) emerged from an analysis of the sub themes. One of these themes was right to access which was emerged from an analysis of 6 sub themes. Conclusion: These sub themes that were obtained from an analysis of descriptive expressions of the participants, are: right to access to housing, right to access to education and information, right to access to job facilities, right to access to medical care and rehabilitation, right to access to rest, leisure and sport and right to access to places and transportation system. The right to access theme, was then categorized in to the civil rights field. In this article we will describe the right to access as it was experienced by those physically disabled people who participated in the interviews

Heterogeneity of HIV incidence : a comparative analysis between fishing communities and in a neighbouring rural general population, Uganda, and implications for HIV control

Objectives To describe HIV heterogeneity in rural Uganda using incidence data collected between January 2012 and December 2014 among fishing cohort (FC) and in an adjacent rural general population cohort (GPC). Methods In the FC, eligible HIV high-risk adults aged 18+ years were enrolled, followed and HIV tested every 3 months. Demographic and sexual behaviour data were also collected. The GPC, approximately 47 km away from the FC, was followed through annual surveys, and sociodemographic and behavioural data collected. A subset of GPC with comparable risk profiles to the FC was selected. We presented sociodemographic and risk profiles and also computed stratified HIV incidence. Cox regression was used to assess factors associated with HIV incidence. Results Overall HIV incidence was higher in the FC than in the ‘high-risk’ GPC, 6.04 and 0.56 per 100 person years at risk, respectively, with a rate ratio (RR) of 10.83 (95% CI 6.11 to 19.76). This was higher among those aged 18–24 years, unmarried and those with more than two sex partners in the past year, RR of 15.44, 22.99 and 19.29, respectively. In the FC, factors associated with high incidence in multivariate analysis were duration in the community and unprotected sex. The factors in the GPC were ethnicity, marital status and duration in the community. Conclusions We have observed a substantial heterogeneity in HIV incidence. The high incidence in fishing communities is contributing greatly to the overall HIV burden in Uganda, and thus urgent combination prevention efforts are needed towards national goal to reduce HIV epidemic

Effects of late flushing and ewe breed on lamb mortality at birth.

A total of 92 Zel and 92 Zel×Shal ewes, 3–5 years of age and body weight of between 35 and 45 kg were randomly allocated in to four groups in order to determine effects of late flushing and breed on lamb mortality at birth. A completely randomized design in factorial arrangement with two factors (Flushing & Breed) and two levels were used. Ewes were fed in two nutritional groups including none flushing diet (2 mcal/kg metabolizeble energy, 11.5 percent crud protein and 1.7 kg/ewe/day dry matter intake) and flushing diet (2.2 mcal/kg metabolizeble energy, 11.5 percent crud protein and 1.7 kg/ewe/day dry matter intake). The flushing continued for last six week of pregnancy. Animals were housed in pens (10 ewes/pen) and allowed free access to water. The results showed that late flushing had a significant effect on lamb mortality at birth (P<0.05). Zel breed had lower lamb mortality than Zel×Shal breed (P<0.05)

The effects of different concentrations of probiotic Saccharomyces cerevisia on growth performance and survival rate of rainbow trout (Oncorhynchus mykiss), fry and resistance against salinity

In the present study, a yeast strain Saccharomyces cerevisia var. elipsoidous, acting as probiotic, was administered to rainbow trout (Oncorhynchus mykiss Walbaum, 1792) fry during a period of 21 days and the effects of the yeast on improvement of growth and resistance against environmental stress were evaluated with respect to fish fed on yeast free feed (control group). The control treatment consisted of a standard commercial diet, and the treatments consisted of the control diet supplemented with 0, 1, 5 and 10% yeast (w/w). The results demonstrate the beneficial effects of probiotics on the characteristics of rainbow trout, as the Specific Growth Ratio (SGR), body weight gain (%BWG) and protein conversion ratio (PER) in 5% yeast-fed fish were significantly (P&lt;0.05) enhanced by probiotic administration. On the contrary, no effect on the fry growth performance, mortality, condition factor (CF), food conversion ratio (FCR) and histological assessment was shown. A significant (P&lt;0.05) increase in lipid content of the carcass was detected in diets with probiotic compareD to 0% and the control treatments. Ash and protein contents of the carcass increased and decreased with an increase in yeast amount, respectively. Challenge with different levels of salinity (10 and 15 ppt) after 24 h revealed 100% survival in treatments containing yeast as probiotic, and difference with control group was significant (p&lt;0.05) indicating that S. cerevisia could enhance the resistance against salinity stress. Addition of yeast in concentration of 5% to the diet is recommended during the early period of rainbow trout fry farming to achieve the best results on growth performance and feed efficiency.Keywords: Saccharomyces cerevisia var. elipsoidous, Oncorhynchus mykiss, probiotic, survival and growth rate, carcass qualityAfrican Journal of Biotechnology, Vol. 13(10), pp. 1160-1168, 5 March, 201

Edge-illumination x-ray phase contrast imaging with Pt-based metallic glass masks

Edge-illumination x-ray phase contrast imaging (EI XPCI) is a non-interferometric phase-sensitive method where two absorption masks are employed. These masks are fabricated through a photolithography process followed by electroplating which is challenging in terms of yield as well as time- and cost-effectiveness. We report on the first implementation of EI XPCI with Pt-based metallic glass masks fabricated by an imprinting method. The new tested alloy exhibits good characteristics including high workability beside high x-ray attenuation. The fabrication process is easy and cheap, and can produce large-size masks for high x-ray energies within minutes. Imaging experiments show a good quality phase image, which confirms the potential of these masks to make the EI XPCI technique widely available and affordable