98 research outputs found
Cluster approximation solution of a two species annihilation model
A two species reaction-diffusion model, in which particles diffuse on a
one-dimensional lattice and annihilate when meeting each other, has been
investigated. Mean field equations for general choice of reaction rates have
been solved exactly. Cluster mean field approximation of the model is also
studied. It is shown that, the general form of large time behavior of one- and
two-point functions of the number operators, are determined by the diffusion
rates of the two type of species, and is independent of annihilation rates.Comment: 9 pages, 7 figure
Heteropolyacides as green and reusable catalysts for the synthesis of [3,4-b][1,3,4] thiadiazines
Synthesis of [3,4-b][1,3,4]thiadiazines from the condensation of 4-amino-6-methyl-3-thioxo-1,2,4-triazine-5(2H)-one (AMTTO) or 4-amino-1,4-dihydro-5-methyle-1,2,4-triazole-5-thione (AMTT) with phenacyl bromide in the presence of a catalytic amount of various heteropolyacids (HPAs) under refluxing conditions is reported. DOI: http://dx.doi.org/10.4314/bcse.v28i1.
Identify and prioritize effective factors in welcoming short courses of weaving carpet in the municipality's cultural centers of Tehran
Background and Objectives: In handicraft literature, the art of handmade carpets is about what is woven and threaded by hand. Two thousand years of Iranian culture and civilization and all the technical chievements of Iranians in the field of handicrafts are summarized in the carpet (weaving carpet), as much as that the structure of Iranian architecture can be known similar to the carpet. Considering the value and importance of handmade carpets and its training in Iran, we study the issue that carpet weaving is one of the oldest economic activities in Iran, according to this background The purpose of this research is to identify and prioritize the effective factors in welcoming the short courses of weaving carpet in the municipality's cultural centers of Tehran. The statistical population in this research includes all those who welcome the art of carpet weaving, so the statistical population of this research includes all the comprehensive and carpentry specialists in the municipality's cultural centers of Tehran. Methods: Research method in this research is applied in terms of purpose and in term of nature is description _ survay .the statistical population in this research is all people who welcome the art of carpet. The sampling method was based on cluster sampling method. In this method, a sample, comprehensive and carpentry specialists were considered in 10 cultural centers of Tehran municipality, whose total number was 126, and the number of carpet specialists was 10, and a total of statistical samples The research was 136 people. To measure the variables in this research, a researcher-made questionnaire was developed for effective factors in welcoming short courses of carpet training. Smart PLS software was used to implement the structural model of the research. Findings: The results showed that all factors are effective in welcoming short-term carpet weaving training courses in cultural centers of Tehran Municipality. Conclusion: In this research, 7 factors were considered to welcome learners from carpet weaving training in the studied cultural centers. These 7 factors are advertising, income, aesthetics, originality of Iranian carpets, interest, cultural needs and educational atmosphere. Considering the existence of this field in cultural centers of different regions of Tehran and recognizing the priorities of learners with different social and cultural origins and the activity of various cultural centers in Greater Tehran, it was found that the four main factors (advertising, income, educational space and interest) which have most effection in welcoming short -term carpet weaving training courses ,should be studied .Eventually The results showed that all the factors affecting the short-term courses of weaving carpet in the municipality's cultural centers And the most important and most influential factor in welcoming short courses in carpet weaving in the municipality's cultural centers are interest and the least influential factor in advertising.
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Brief research report: Quantitative analysis of potential coronary microvascular disease in suspected long-COVID syndrome
BACKGROUND: Case series have reported persistent cardiopulmonary symptoms, often termed long-COVID or post-COVID syndrome, in more than half of patients recovering from Coronavirus Disease 19 (COVID-19). Recently, alterations in microvascular perfusion have been proposed as a possible pathomechanism in long-COVID syndrome. We examined whether microvascular perfusion, measured by quantitative stress perfusion cardiac magnetic resonance (CMR), is impaired in patients with persistent cardiac symptoms post-COVID-19. METHODS: Our population consisted of 33 patients post-COVID-19 examined in Berlin and London, 11 (33%) of which complained of persistent chest pain and 13 (39%) of dyspnea. The scan protocol included standard cardiac imaging and dual-sequence quantitative stress perfusion. Standard parameters were compared to 17 healthy controls from our institution. Quantitative perfusion was compared to published values of healthy controls. RESULTS: The stress myocardial blood flow (MBF) was significantly lower [31.8 ± 5.1 vs. 37.8 ± 6.0 (μl/g/beat), P < 0.001] and the T2 relaxation time was significantly higher (46.2 ± 3.6 vs. 42.7 ± 2.8 ms, P = 0.002) post-COVID-19 compared to healthy controls. Stress MBF and T1 and T2 relaxation times were not correlated to the COVID-19 severity (Spearman r = −0.302, −0.070, and −0.297, respectively) or the presence of symptoms. The stress MBF showed a U-shaped relation to time from PCR to CMR, no correlation to T1 relaxation time, and a negative correlation to T2 relaxation time (Pearson r = −0.446, P = 0.029). CONCLUSION: While we found a significantly reduced microvascular perfusion post-COVID-19 compared to healthy controls, this reduction was not related to symptoms or COVID-19 severity
Pregnancy, prescription medicines and the potential risk of herb-drug interactions:a cross-sectional survey
Funding All funding was from institutional resource. JSM, AS are employed by the University of Aberdeen. DS is employed by the Robert Gordon University. BP and CR are employed by NHS Scotland. ARP and MAH are employed by the Hamad Medical Corporation. Qatar. NI is a postgraduate student at the University of Aberdeen.Peer reviewedPublisher PD
Soy protein–gum karaya conjugate: emulsifying activity and rheological behavior in aqueous system and oil in water emulsion
The main objective of this study is to investigate the effects of mixing and conjugation of soy protein isolate (SPI) with gum karaya on the characteristics of the hybrid polymer (protein–gum) in both aqueous systems and oil-in-water (O/W) emulsions. It was hypothesized that the covalent linkage of gum karaya with SPI would improve the emulsifying activity and rheological properties of both polymers. Conjugation occurred under controlled conditions (i.e., 60 °C and 75 % relative humidity, 3 days). The conjugated hybrid polymer produced smaller droplet with better uniformity, higher viscosity and stronger emulsifying activity than native gum karaya, suggesting the conjugated polymer provided a bulkier secondary layer with more efficient coverage around oil droplets, thereby inducing stronger resistance against droplet aggregation and flocculation. Emulsions containing the native gum karaya produced the largest droplet size among all prepared emulsions (D 3,2 = 8.6 μm; D 4,3 = 22.4 μm); while the emulsion containing protein–gum conjugate (1:1 g/g) had the smallest droplet size (D 3,2 = 0.2 μm; D 4,3 = 0.7 μm) with lower polydispersity. The protein–gum conjugate (1:1 g/g) also showed the highest elastic and viscous modulus, the lowest polydispersity (span) and the highest emulsifying activity among all native, mixed and conjugated polymers. Therefore, the percentage of gum karaya used for production of O/W emulsion can be decreased by partially replacing it with the conjugated gum
Proteins of Leishmania (Viannia) shawi confer protection associated with Th1 immune response and memory generation
<p>Abstract</p> <p>Background</p> <p><it>Leishmania (Viannia) shawi </it>parasite was first characterized in 1989. Recently the protective effects of soluble leishmanial antigen (SLA) from <it>L. (V.) shawi </it>promastigotes were demonstrated using BALB/c mice, the susceptibility model for this parasite. In order to identify protective fractions, SLA was fractionated by reverse phase HPLC and five antigenic fractions were obtained.</p> <p>Methods</p> <p>F1 fraction was purified from L. (V.) shawi parasite extract by reverse phase HPLC. BALB/c mice were immunized once a week for two consecutive weeks by subcutaneous routes in the rump, using 25 μg of F1. After 1 and 16 weeks of last immunization, groups were challenged in the footpad with L. (V.) shawi promastigotes. After 2 months, those same mice were sacrificed and parasite burden, cellular and humoral immune responses were evaluated.</p> <p>Results</p> <p>The F1 fraction induced a high degree of protection associated with an increase in IFN-γ, a decrease in IL-4, increased cell proliferation and activation of CD8<sup>+</sup>T lymphocytes. Long-term protection was acquired in F1-immunized mice, associated with increased CD4<sup>+ </sup>central memory T lymphocytes and activation of both CD4<sup>+ </sup>and CD8<sup>+ </sup>T cells. In addition, F1-immunized groups showed an increase in IgG2a levels.</p> <p>Conclusions</p> <p>The inductor capability of antigens to generate memory lymphocytes that can proliferate and secrete beneficial cytokines upon infection could be an important factor in the development of vaccine candidates against American Tegumentary Leishmaniasis.</p
Confirmatory Factor Analysis of the Finnish Job Content Questionnaire (JCQ) in 590Professional Musicians
Chiral phase transition of a dense, magnetized and rotating quark matter
We investigate the chiral symmetry restoration/breaking of a dense,
magnetized and rotating quark matter within the Nambu Jona-Lasinio model
including and numbers of flavors and colors, respectively.
Imposing the spectral boundary conditions, as well as the positiveness of
energy levels, lead to a correlation between the magnetic and rotation fields
such that strongly magnetized plasma can not rotate anymore. We solve the gap
equation at zero and finite temperature. At finite temperature and baryon
chemical potential , we sketch the phase diagrams and
in different cases. As a result, we always observe
inverse-rotational catalysis mean to decrease by increasing .
But the magnetic field has a more complex structure in the phase diagram. For
slowly rotating plasma, we find that decreases by increasing , while
in the fast rotating plasma we see that increases by increasing .
Also, we locate exactly the position of Critical End Point by solving the
equations of first and second derivatives of effective action with respect to
the order parameters, simultaneously.Comment: 18 pages, 15 figures, 5 tables, comments are welcom
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