h rezaee

One of the most important inputs in all economic sectors of Iran is water. The solution to the shortage of water resources in Iran is not more water supply, but an effective solution to adopt policies and measures that change the economic structure and pattern of water consumption. In this study, the income elasticity and price elasticity of Kermanshah urban water demand and the estimation of daily consumption of each person during the period 1392-1397 have been estimated. For this purpose, at first, the general form of water demand function was calculated by maximizing an Aston Gray utility function and was estimated using the VAR model, based on the Johansen method of Kermanshah urban water demand function. According to the results, urban water demand is inversely related to water prices and directly related to income. Price elasticity indicates a negative relationship between price changes and water demand. If the price of water increases by 10%, the demand for it will decrease by 4.3%. On the other hand, the absolute value of price elasticity and revenue elasticity of water is less than one. Also in this research, ARDL model has been used to investigate the long-term, short-term relationship, error correction test and tensile tests as a complementary and comparative method with VAR model of ARDL model. In both models, the price elasticity is less than one, ie with a 10% increase in price, consumption decreases by less than 10%. The non-zero price elasticity of water indicates that increasing tariffs can be used as a way to reduce water consumption, at least in the short term. The results showed that according to the criterion of the usefulness function of acetone, the minimum water consumption for each subscriber in Kermanshah is about 8.21 cubic meters (8210 liters) per month. According to the model, this amount is about 273 liters per day. That's about 273 liters a day, according to model estimates.

Avian influenza (AI) caused by AI virus subtype H9N2 is a prevalent viral disease with enormous economic losses in poultry farms through significant respiratory and gastrointestinal manifestations. The degree of protection obtained from a vaccine strongly depends on the level of antigenic similarity between challenge and vaccine virus.

The study aimed at investigating the possible effects of continuous antigenic changes occurring in circulating Iranian viruses since 1998 on the commercial vaccines outcome by using vaccine seeds from earlier outbreaks for inhibiting viral replication in target organs of broilers challenged with the recent isolate.

Ninety broilers at one day of age were randomly allocated into 5 groups and vaccinated with autogenous or commercial vaccines (A or B). Two remaining groups consisted of challenged without vaccination and intact birds. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed on the trachea and faecal samples of challenged chickens with recent H9N2 virus to determine viral load. Moreover, humoral antibodies titers were evaluated by hemagglutination inhibition (HI) assay.

There was no significant difference in H9N2 viral load in the trachea among vaccinated groups on 5 days post challenge (DPC), but on 15 DPC, the autogenous vaccine significantly lowered viral load compared to commercial vaccines (P≤0.05). No significant differences in faecal swab’s viral load was observed between autogenous and commercial vaccine A, and both of them significantly inhibited viral load compared to unvaccinated group (P≤0.05). In addition, the autogenous vaccine elicited the highest HI titer.

Inactivated vaccines that use isolates from previous outbreaks are no longer able to induce proper immunity against recent H9N2 viruses. It seems the time to change vaccine strains to more recent isolates that have better antigenic similarity with current circulating H9N2 viruses in the region has come.

Coronaviruses (AvCoV) which include infectious bronchitis virus (IBV) and other bird coronaviruses belong to the genus gammacoronavirus, subfamily Coronavirinae. One of the most prominent representatives of gammacoronavirus genus is infectious bronchitis virus (IBV) which is a highly contagious viral pathogen of chickens causing considerable economic losses to the poultry industry. IBVs mostly affect the respiratory, urinary, and reproductive tracts leading to a substantial drop in production. Backyard poultry in the villages usually share their food and water with free flight birds which puts them at serious risk of disease transmission. Furthermore, the poor hygienic measurements which are often used in backyard flocks make them a potential reservoir for diseases that can be transferred to commercial poultry flocks. Live bird markets (LBMs) which receive live poultry to be resold or slaughtered and sold onsite play a significant role in spreading infectious diseases among the different bird species. In the present study, a number of 354 cloacal swab samples were collected from different bird species from LBMs of Gilan province. Subsequently, after RNA extraction, reverse transcription-polymerase chain reaction (RT-PCR) technique was carried out using specific primers of S1 gene to detect coronavirus infectious bronchitis virus. Two samples from backyard chickens were reported to be positive to coronavirus which were named Iran/Backyardchicken96/2017 and Iran/Backyardchicken94/2017. The results of the phylogenetic analysis demonstrated that these two isolates are placed in QX and IS-1494 strains, respectively. On a final note, the obtained results highlighted the role of live birds offered in LBMs in the epidemiology of IBV and the transmission of the virus to the industrial flock.

Regarding the impact of bilingualism and cochlear implantation on the language development and metalinguistic skills, examining these skills in bilingual children in different languages, especially bilingual children with normal and cochlear implantation, can lead us to a greater recognition of the language development in children and the related factors. The present study aims to investigate and compare the mean length of utterance and lexical richness with lexical awareness (content and structural aspect) between the normal and cochlear implantation children in the first grade in Persian and Azeri.   Six bilingual children with cochlear implantation were selected from the first grade of exceptional school in city of Zanjan in year 97-98 and six normal counterparts were selected matched for gender, age, and socio-economic conditions. Then, mean length of utterance and lexical richness were compared with metalinguistic skills tests. For studying mean length of utterance and lexical richness, continuous speech test and for studying metalinguistic skills, lexical awareness test (including content and structural aspect of word definition) were used. Data analysis in Azeri language showed that mean lengthof utterance and lexical richness in thefirst grade of hard of hearing bilingual children with cochlear implantation in Azeri- Persian is delayed (p<0.05). But in Persian language of language development indices, only the mean lengthof utterance is delayed (p<0.05). No significant difference was found in any of content and structural aspects of lexical awareness definition in hard of hearing children with cochlear implantation (p>0.05). The low level of meta-language proficiency of subjects in metalinguistic tests in Azeri language can be attributed to the official teaching of Persian language in schools. Consistent with the results of this study, the mean continuous speech scores showed that the performance of the first grade of normal bilingual children in lexical richness and Mean length of utterance in Persian language is better than bilingual children with cochlear implantation.

Newcastle disease virus (NDV) is a prototype member of avian paramyxovirus serotype 1 (APMV-1), which causes severe and contagious disease in the commercial poultry and wild birds. In this study, we report the results of phylogenetic analyses of recent NDVs isolated from Markazi province of Iran during a recent outbreak in the commercial broiler with respiratory signs and digestive system lesions. Phylogenetic analysis revealed that isolate was clustered within class II NDV, in sub-genotype VII-g. This NDV isolates shared high homology with the prevalent genotype NDV strains that circulate in China and Taiwan (95.39%-84.89%).   Overall, our results confirmed the presence of genotype VII-g in Iran (The first report) and indicated that different genotypes of NDV could circulate simultaneously among poultry (VII-d & VII-i). The phylogenetic characterization of these isolates helps to characterize the evolution of NDV and may help with the development of vaccines specific to our regional necessities.

A total of 179,460 monthly test-day milk records (thrice a day milking) obtained from 17,946 Iranian Holstein heifers distributed in 287 herds and calved from 1986 to 2001 were used to predict breeding value of animals. Monthly test-day milk production was analysed by applying a covariance function in which the effects of herd-year-season of production (HYSOP), age at test day (covariate), additive genetic and permanent environmental effects were included. Orthogonal legendre polynomials up to order 5 (quartic) were also implemented in the covariance model to take account of the genetic and environmental aspects of milk production variation over the course of the lactation. In the present research, breeding values of individual animals based upon 305-day and monthly test-day milk yields were compared. The results indicated that ranking of ten top sires, dams as well as progenies changed as the genetic evaluation of animals switched from the traditional (based on 305-day milk yield) to the new method that was based on the covariance function. Regression analysis of average breeding value of progenies on the first year of their calving showed that the amount of genetic trend obtained from the covariance function for 305-day milk yield was greater than that of the 305-day model (11.607 vs. 3.860 Kg/year) over the period of 16 years of calving. The phenotypic trend for lactation milk yield was 92.97 Kg per year which was statistically significant. This finding indicates that a large proportion of annual increase of milk production of Holstein heifers in Iran has been due to environmental rather than genetic improvement.