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The purpose of this paper is using the proposed two step method to impose essential boundary conditions for improving the accuracy of solution field. In the proposed approach, imposing essential boundary conditions in transient heat flow within two-dimensional region is extended in two steps. The essential boundary conditions are defined on Dirichlet boundary as determined temperatures and independent of time. In the first step, Dirichlet boundary conditions are weakly built into the variational formulation, choosing weight function, appropriately. In the second step, with fixed condition, the system of equations is appropriately adjusted. For investigation of the efficiency of the proposed approach, several 2D numerical examples have been performed. The results demonstrate significant improvement in accuracy and rate of convergence in comparison with direct imposition of essential boundary condition. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the notion of (m, n)-algebraically compact modules as an analogue of algebraically compact modules and then we show that (m, n)-algebraically compactness and (m, n)-pure injectivity for modules coincide. Moreover, further characterizations of a (m, n)-pure injective module over a commutative ring are given. [ABSTRACT FROM AUTHOR]

Background: The protozoan parasite Toxoplasma gondii can infect any warm blooded nucleated cells. One of the ways for human infection is ingestion of oocysts directly from soil or via infected fruits or vegetables. To survey the potential role of T. gondii oocyst in soil samples, the present study was conducted in Tehran City, Iran. Methods: A total of 150 soil samples were collected around rubbish dumps, children's play ground, parks and public places. Oocysts recovery was performed by sodium nitrate flotation method on soil samples. For molecular detection, PCR reaction targeting B1 gene was performed and then, the positive results were confirmed using repetitive 529 bp DNA fragment in other PCR reaction. Finally, the positive samples were genotyped at the SAG2 locus. Results: Toxoplasma DNA was found in 13 soil samples. After genotyping and RFLP analysis in SAG2 locus, nine positive samples were revealed type III, one positive sample was type I whereas three samples revealed mixed infection (type, I & III). Conclusion: The predominant genotype in Tehran soil samples is type III. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii is an obligate intracellular parasite that infects humans at high prevalence rates. The virulent RH strain of T. gondii is generally considered to have lost its cyst forming capacity. This study performed to obtain tissue cysts in mice infected with tachyzoites of RH strain treated with sulfadiazine (SDZ). It provides the opportunity to analyze the conversion of tachyzoite to bradyzoite stage of the RH strain, followed by stage-specific gene-expression analyzing. Methods: Two groups of Swiss-Webster and BALB/c mice were infected subcutaneously with 104 tachyzoites of T. gondii, RH strain and given SDZ (300 mg/l) with NaHCO3 (5 g-1) in drinking water from day1 to day 14 post infection (p.i). The infected mice were sacrificed on day 50 post infection. Their brains were removed and the numbers of tissue cysts were microscopically counted. Total RNA was extracted from brains and cDNA synthesis was carried out. Finally, RT-PCR (Reverse transcription PCR) was used to detect the expression of bradyzoite (BAG1) and tachyzoite (SAG1) specific genes during tachyzoite / bradyzoite stage conversion. Results: Sixty five percent of all infected mice were survived. Cysts were detectable in mice brain (45%) on day 50 p.i. Also RT-PCR of the brain samples was positive for SAG1 and BAG1. Conclusion: It seems that conversion of tachyzoites to bradyzoites in brain of mice undergoing SDZ was not completed until 50 days after inoculation. [ABSTRACT FROM AUTHOR]

The isogeometric analysis is increasingly used in various engineering problems. It is based on Non-Uniform Rational B-Splines (NURBS) basis function applied for the solution field approximation and the geometry description. One of the major concerns with this method is finding an efficient approach to impose essential boundary conditions, especially for inhomogeneous boundaries. The main contribution of this study is to use the well-known Lagrange multiplier method to impose essential boundary conditions for improving the accuracy of the isogeometric solution. Moreover, Dirichlet boundary conditions on the derivatives of the solution field (which are not directly defined as independent degrees of freedom) can be treated easily. The Lagrange multipliers must be interpolated on a set of boundary points. Among the different available choices for the boundary interpolation points, the Greville abscissas are considered in this work. Several plate problems have been solved, which demonstrate significant improvement in accuracy and rate of convergence in comparison with the direct imposition of essential boundary conditions. [ABSTRACT FROM AUTHOR]

Background: The assays currently available for the detection of specific anti-Toxoplasma antibodies may vary in their abilities to detect serum immunoglobulins, due to the Lack of a purified standardized antigen. The aim of this study was evaluation the recombinant Toxoplasma gondii SAG1 antigen for the serodiagnosis of acute and chronic toxoplasmosis. Methods: This study describes an ELISA using recombinant SAG1 for detection of IgM and IgG antibodies against Toxoplasma gondii in human sera. Genomic DNA of T. gondii (RH Strain) was isolated and PCR reaction was performed. Recovered DNA was cloned into PTZ57R cloning vector. The recombinant plasmid was detected by restriction analysis. The SAG1 gene was subcloned in the pET- 28a expression vector. Protein production was then induced with 1 mM isopropyl-D - thiogalactopyranoside (IPTG). A total of 204 sera were tested using a commercial IgG and IgM ELISA kit (Trinity, USA) as gold standard prior to testing them with the recombinant antigen. Results: Tested sera were divided into the following groups:(a) The 74 T. gondii IgG positive (b) 70 T.gondii IgM positive (c) 60 sera who had no serological evidence of toxoplasmosis as negative sera.To determine the specificity of the test, we used other parasitic diseases including echinococusis (N=5), malaria (N=14), leishmaniasis (N=7),fasciolasis (N=4 ), sterengyloidiasis (N=1 ). Sensitivity and specificity of the generated recombinant IgG ELISA in comparison with commercial ELISA (Com ELISA) were 93% and 95%, and the sensitivity and specificity of the generated recombinant IgM ELISA were 87% and 95% respectively. Conclusion: The results acquired here show that this antigen is useful for diagnostic purposes and could be replaced by lysed, whole cell antigens for diagnosis of chronic toxoplasmosis. [ABSTRACT FROM AUTHOR]

Background: Plasmodium vivax is the predominant species causes of malaria with about 90% total annual reported malaria in Iran. This study conducted to determine the susceptibility of Plasmodium vivax isolates to chloroquine in Sistan and Balochistan Province, southeastern Iran. Methods: A total 270 subjects with symptomatic malaria and confirmed P. vivax infection completed the designed 28-day in vivo study. The thick and thin film blood smears were screened for malaria parasites by microscopy. The nested PCR was applied using the Plasmodium 18 subunit ribosomal ribonucleic (Ssr RNA) genes for detecting mixed infections and diagnosis of parasites in the samples with low parasite on days 0, 5, 6, 7, and 28. Results: P. vivax was cleared in 15%, 50%, 95%, and 100% of patients on days 1, 2, 3, 4 respectively by microscopy assessment. Six patients were exhibited specific P. vivax band in nested PCR on day 5. No recurrence was observed on days 7, 14 and 28. Mean (±standard deviation) parasite clearance time was 2.41 (±0.8) days. Conclusion: P. vivax is still susceptible to chloroquine in Southeatern Iran. This finding is compatible with results of neighboring countries Pakistan and Afghanistan. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to conduct a sero-epidemiological survey in Meshkinshahr, Ardabil Province, northwestern Iran to detect the rate of hydatidosis in the city and nearby villages. Literature shows that no such study has been conducted so far. Methods: Overall, 670 serum samples were collected from 194 males and 476 females from patients referred to different health centers of the region. All patients filled out a questionnaire and an informed consent. Sera were analyzed using indirect-ELISA test. Ten μg /ml antigens (Antigen B derived from hydatid cyst fluid), serum dilutions of 1:500 and conjugate anti-human coombs with 1:10000 dilutions were utilized to perform the test. Data analysis was conducted using SPSS software ver. 11.5. Results: The seroprevalence of human hydatidosis was 1.79% by ELISA test in the region. This rate for females was 1.68% and males 2.6%, respectively. There was no significant difference as regards all factors studied and the seropositivity. According to job, farmers and ranchmen had the highest rate of infection as 3.17%. The sero-prevalence of infection was 2.6%% in illiterate people which showed the highest rate. As regards residency, urban life showed no significant difference with rural life (1.1% vs. 2.58%). Age group of 69-90 yr old, with 4.62% as prevalence had the highest rate of positivity. Conclusion: Obtained sero-prevalence of hydatidosis shows more or less a resemblance to other cities of Iran, although due to the specific condition of the city we expected more rate of sero-positivity. [ABSTRACT FROM AUTHOR]

Background: Schizophrenia is a serious, chronic, and often debilitating neuropsychiatric disorder. Its causes are still poorly understood. Besides genetic and non-genetic (environmental) factors are thought to be important as the cause of the structural and functional deficits that characterize schizophrenia. This study aimed to compare Toxoplasma gondii infection between schizophrenia patients and non-schizophrenia individuals as control group. Methods: A case-control study was designed in Tehran, Iran during 2009-2010. Sixty-two patients with schizophrenia and 62 non-schizophrenia volunteers were selected. To ascertain a possible relationship between T. gondii infection and schizophrenia, anti-Toxoplasma IgG antibodies were detected by indirect-ELISA. Data were statistically analyzed by chi- square at a confidence level of 99%. Results: The sero-positivity rate among patients with schizophrenia (67.7%) was significantly higher than control group (37.1) (P <0. 01). Conclusion: A significant correlation between Toxoplasma infection and schizophrenia might be expected. [ABSTRACT FROM AUTHOR]

Background: Toxoplasmosis is a worldwide endemic disease. In congenitally infected infants and AIDS patients, toxoplasmosis causes high rates of morbidity and mortality. In these cases antibody detection is difficult; so detection of parasite or its components could be useful tool for early detection and following treatment of the infection. Methods: Sixty-three BALB/c mice were injected intra-peritoneal with 5×10³ tachyzoites of Toxoplasma gondii RH strain, nine mice were sacrificed daily for 7 days. Fourteen mice were injected with phosphate buffer saline as control group. Dot-ELISA was performed for detection of T.gondii antigen in mice sera and capture - ELISA was done as golden standard assay too. Results : Toxoplasma gondii antigen was detected from day 2 in mice sera ; 22% of mice sera on day 2, 33% on day 3,77% on day 4 and 100% on day 5 till their death on day 7 had shown antigenemia by dot - ELISA, no positive result was detected in control mice by dot- ELISA. Conclusion: Dot-ELISA is a sensitive method for diagnosis of T. gondii infection in the animal model; also, this technique is more rapid and easy to perform method in comparison with capture- ELISA. [ABSTRACT FROM AUTHOR]

Background: The IFA test is one of the most usual methods for detecting anti-Toxoplasma antibodies, although it has not any unique standardization. It seems that the microscopic judgment of results is an important confounder in IFA test. Therefore, we conducted the present study to clarify the role of microscopic observer, and other confounders on the test. Methods: Eighty sera were collected from patients suspicious to toxoplasmosis for detection IgG anti-T. gondii by this test. Samples were examined against different series of antigens, IgG antihuman conjugates, and observers. Results: There were no significant differences between the two series of antigens and conjugates. For the observers groups the kappa coefficient of the test results in the experts group (0.97, 0.94- 1.00) were significantly higher than the less experienced observers (0.77, 0.68-0.87). Conclusion: We recommend the IFA test to be performed only in reference laboratories and by laboratory technicians that have enough experience for this test. Otherwise, we suggest the substitution of this test with other tests like ELISA for the diagnosis and epidemiological studies. [ABSTRACT FROM AUTHOR]

In this article, the Ant Colony Optimization (ACO) algorithm is employed to size optimization of scissor-link foldable structures. The advantage of using ACO lies in the fact that the discrete spaces can be optimized with no complexity. The algorithm selects the optimum cross-sections from the available sections list. Elastic behavior is assumed for the formulation of the problem. In addition to strength constraints, the displacement constraints are considered for design. Here, the displacement method is used for analysis employing a special 3-node beam known as a uniplet. Two design examples are presented to demonstrate the performance of the algorithm. [ABSTRACT FROM AUTHOR]

Effect of ethanol consumption on fear response in human and conventional animal models (rodents) is controversial. The present study aimed to investigate the effect of ethanol administration on fearfulness in poultry as an alternative animal model. Being a reliable measure in avian species, tonic immobility was used to evaluate the fear response in 60 roosters orally administered with ethanol. Duration of tonic immobility was higher in alcohol-exposed birds compared to the control birds (P<0.05), suggesting that dosing the roosters with ethanol was associated with an increased fear response which makes poultry as a plausible alternative model in behavioral studies. [ABSTRACT FROM AUTHOR]

In the paper, a mesh-free method called smoothed particle hydrodynamics (SPH) is presented to deal with seepage problem in porous media. In the SPH method, the computational domain is discredited by means of some nodes, and there is no need for computational domain meshing. Therefore, it can be said that it is a truly mesh-free approach. The method has been applied to analyze seepage problem in earth dams and foundations. The results were compared with ones obtained by analyzing with the finite element-based software, Geostudio (SEEP/W). There was a good agreement between results. Moreover, the SPH method is efficient and capable of seepage analysis specifically for the problems with complex geometry. [ABSTRACT FROM AUTHOR]