213 research outputs found

    Neighborhood Semantics for Basic and Intuitionistic Logic

    Get PDF
    In this paper we present a neighborhood semantics for Intuitionistic Propositional Logic (IPL). We show that for each Kripke model of the logic there is a pointwise equivalent neighborhood model and vice versa. In this way, we establish soundness and completeness of IPL with respect to the neighborhood semantics. The relation between neighborhood and topological semantics are also investigated. Moreover, the notions of bisimulation and n-bisimulation between neighborhood models of IPL are defined naturally and some of their basic properties are proved. We also consider Basic Propositional Logic (BPL), a logic weaker than IPL introduced by Albert Visser, and introduce and study its neighborhood models in the same manner

    Janssen effect and the stability of quasi 2-D sandpiles

    Full text link
    We present the results of three dimensional molecular dynamics study of global normal stresses in quasi two dimensional sandpiles formed by pouring mono dispersed cohesionless spherical grains into a vertical granular Hele-Shaw cell. We observe Janssen effect which is the phenomenon of pressure saturation at the bottom of the container. Simulation of cells with different thicknesses shows that the Janssen coefficient κ\kappa is a function of the cell thickness. Dependence of global normal stresses as well as κ\kappa on the friction coefficients between the grains (μp\mu_p) and with walls (μw\mu_w) are also studied. The results show that in the range of our simulations κ\kappa usually increases with wall-grain friction coefficient. Meanwhile by increasing μp\mu_p while the other system parameters are fixed, we witness a gradual increase in κ\kappa to a parameter dependent maximal value

    Induction of CD14 Expression and Differentiation to Monocytes or Mature Macrophages in Promyelocytic Cell Lines: New Approach

    Get PDF
    Purpose: CD14, one of the main differentiation markers on the surface of myeloid lineage cells, acts as a key role in activation of LPS-induced monocytes. LPS (lipopolysaccharide) binds to LPS-binding protein in plasma and are delivered to the cell surface receptor CD14. In this study, Various stimuli [Dimethyl Sulfoxide (DMSO), active 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and LPS], either alone or in combination, have been recognized that have an effect on the level of CD14 expression in the human HL-60 and U937 promonocytic cell lines and therefore induce their terminal differentiation into monocytes or mature macrophages. Methods: U937 and HL-60 cells were cultured in RPMI 1640 supplemented with 10% FBS. For each cell line, 1×106 cells were seeded for 72 hours with DMSO, 14 days with LPS and 18 days with 1, 25-D3 in each well plate; then ELISA method was used to study their responses to the factors by means of anti-CD14. Results: ELISA assay demonstrated that U937 and HL-60 cells were induced by both [1,25(OH)2D3] and DMSO to obtain characteristics of adherent cells and express CD14 protein; moreover, LPS at a low dose increased CD14 expression on surface of this cells. Conclusion: According to the our results, it is speculated that CD14 gene expression may be induced in human U937 and HL-60 cell lines by different factors including 1,25-D3, DMSO and LPS

    Seroprevalence of and Risk Factors for Toxoplasma gondii among Pregnant Women in Abyek Township of Qazvin Province , Iran (2013)

    Get PDF
     Objective: Toxoplasmosis is an important disease which is caused by the coccidian parasite Toxoplasma gondii. The aim of this study was to determineseroprevalence of and risk factors for T. gondii among pregnant women in Abyek township of Qazvin province by enzyme-linked immunosorbentassay method.Methods: Blood samples were taken from 200 pregnant women referred to the health centers of Abyek township. Immunoglobulin M (IgM)and IgGtiters and effects of some factors on incidence of the disease were evaluated. The collected data were statistically analyzed with SPSS 17 using Chisquaretest.Results: Anti toxoplasma IgM and IgG were positive in 2% and 29% respectively. Seropositive subjects were more frequently seen in women withage >30 years compared to younger women. No significant relationship was found between the seroprevalence of T. gondii infection and level ofeducation, residence area, history of abortion and gestational age.Conclusion: It was indicative of having a latent infection due to the previous exposure to toxoplasma parasite in this region.Keywords: Toxoplasma gondii, Prevalence, Pregnant women, Enzyme-linked immunosorbent assay, Immunoglobulin M

    The Efficacy of “Care for Child Development” Intervention on the Improvement of the Development Skills of Orphanage Children

    Get PDF
    ObjectivesDevelopment refers to the progressive enhancement of skills and functional capacity, i.e., qualitative changes in the child’s functions.The process of development begins before birth and continues throughout life. The present study aims to evaluate the effectiveness of the “Care for Child Development (CCD)” program on 4-42 months children’s developmental skills in orphanages.Materials & MethodsIn this study, two orphanages in the capitals of East and West Azerbaijan provinces were selected using the convenience sampling technique, and thirty children were included. Then, they were randomly divided into two intervention and control groups (each group, N=15). Next, after obtaining consent from the head of the orphanages, a group of volunteers from the healthcare center performed the CCD program, considering children’s chronological ages (4 to 42 months), for three sessions a week, with each session lasting two hours and it lasted for three months. At the end of the intervention process, the Bayley Scale of Infant and Toddler Development 3rd version (BSID-III) and the Ages and Stages Questionnaire-II (ASQ) were completed for the two intervention and control groups to compare them in the cognitive, motor, communication, and personal-social domains. ResultsComparing the two control and intervention groups using the T-test (difference in mean) indicates that except for the domain of cognitive skills (Bayley: P-value = 0.176), there was statistically a significant difference between the two groups in communication (ASQ: P-value= 0.001; Bayley: P-value = 0.003), motor (ASQ: P-value = 0.000; Bayley: P-value = 0.009), and personal-social (ASQ: P-value <0.000)skills.ConclusionIn the present study, it was concluded that it is required to apply interventions, including standard ones such as the CCD program in environments like orphanages, to enhance the developmental skills of those children living in them    

    Improvements to seismicity forecasting based on a Bayesian spatio-temporal ETAS model

    Get PDF
    The epidemic-type aftershock sequence (ETAS) model provides an effective tool for predicting the spatio-temporal evolution of aftershock clustering in short-term. Based on this model, a fully probabilistic procedure was previously proposed by the first two authors for providing spatio-temporal predictions of aftershock occurrence in a prescribed forecasting time interval. This procedure exploited the versatility of the Bayesian inference to adaptively update the forecasts based on the incoming information provided by the ongoing seismic sequence. In this work, this Bayesian procedure is improved: (1) the likelihood function for the sequence has been modified to properly consider the piecewise stationary integration of the seismicity rate; (2) the spatial integral of seismicity rate over the whole aftershock zone is calculated analytically; (3) background seismicity is explicitly considered within the forecasting procedure; (4) an adaptive Markov Chain Monte Carlo simulation procedure is adopted; (5) leveraging the stochastic sequences generated by the procedure in the forecasting interval, the N-test and the S-test are adopted to verify the forecasts. This framework is demonstrated and verified through retrospective early forecasting of seismicity associated with the 2017-2019 Kermanshah seismic sequence activities in western Iran in two distinct phases following the main events with Mw7.3 and Mw6.3, respectively

    Engineering the pH-Sensitivity of the Graphene and Carbon Nanotube Based Nanomedicines in Smart Cancer Therapy by Grafting Trimetyl Chitosan

    Get PDF
    Purpose The aim of this study was to introduce a smart and responsive drug carrier for Doxorubicin (DOX) and Paclitaxel (PAX) for desirable therapeutic application. Method Loading and releasing of DOX and PAX from smart and pH-sensitive functionalized single-walled carbon nanotube (SWCNTs) and graphene carriers have been simulated by molecular dynamics. The influences of chitosan polymer on proposed carriers have been studied, and both carriers were functionalized with carboxyl groups to improve the loading and releasing properties of the drugs. Results The results showed that DOX could be well adsorbed on both functionalized SWCNTs and graphene. In contrast, there was a weak electrostatic and Van der Waals interaction between both these drugs and carriers at cancerous tissues, which is highly favorable for cancer therapy. Adding trimethyl chitosan (TMC) polymer to carriers facilitated DOX release at acidic tissues. Furthermore, at blood pH, the PAX loaded on the functionalized SWCNTs carrier represented the highest dispersion of the drug while the DOX-graphene showed the highest concentration of the drug at a point. In addition, the mean-square displacement (MSD) results of PAX-graphene indicated that the PAX could be adsorbed quickly and be released slowly. Finally, functionalized graphene-TMC-PAX is a smart drug system with responsive behavior and controllable drug release, which are essential in cancer therapy. Conclusion Simultaneous application of the carboxyl group and TMC can optimize the pH sensitivity of the SWCNTs and graphene to prepare a novel and smart drug carrier for cancer therapy.Peer reviewe

    The Relationship between Sex Roles and Childbearing Motivation in Fertile Women, Iran

    Get PDF
    Introduction: This study was conducted to determine the relationship between sex role and women's childbearing motivation.Methods: In this study 841 married female participants lived in urban society of Mashhad were recruited based on a multistage sampling from a variety of settings. Data was gathered using Childbearing Questionnaire (CBQ) and brief form of Bem sex role questionnaire. Analyzed using Pearson correlation coefficient, multiple regression test and independent t-test.Results: Feminine sex role was in significant relationship with positive childbearing motivation (p=.001). Masculine sex role have no relationship with both childbearing motivations. ANOVA showed a difference between the motivations in four groups of participants divided based on sex role scores. LSD test shows that positive motivation in android (p=.013) and masculine (p=.012) groups were significantly less than feminine group. Negative childbearing motivations in feminine group was less than in UN-differentiate group (p=.014). Conclusion: Multiple regression analysis show that positive motivation was in relationship with the feminine sex role and reverse relationship with marriage age. Reproductive health policy makers and family planning counselors can apply study findings in order to plan perfect programs to direct proper fertility behaviors in the society
    corecore