83 research outputs found

    Multi-Dimensional Cosmology and GUP

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    We consider a multidimensional cosmological model with FRW type metric having 4-dimensional space-time and dd-dimensional Ricci-flat internal space sectors with a higher dimensional cosmological constant. We study the classical cosmology in commutative and GUP cases and obtain the corresponding exact solutions for negative and positive cosmological constants. It is shown that for negative cosmological constant, the commutative and GUP cases result in finite size universes with smaller size and longer ages, and larger size and shorter age, respectively. For positive cosmological constant, the commutative and GUP cases result in infinite size universes having late time accelerating behavior in good agreement with current observations. The accelerating phase starts in the GUP case sooner than the commutative case. In both commutative and GUP cases, and for both negative and positive cosmological constants, the internal space is stabilized to the sub-Planck size, at least within the present age of the universe. Then, we study the quantum cosmology by deriving the Wheeler-DeWitt equation, and obtain the exact solutions in the commutative case and the perturbative solutions in GUP case, to first order in the GUP small parameter, for both negative and positive cosmological constants. It is shown that good correspondence exists between the classical and quantum solutions.Comment: 21 pages, 15 figures, minor revision, references adde

    MULTI-DIMENSIONAL COSMOLOGY AND DSR–GUP

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    A multi-dimensional cosmology with FRW type metric having four-dimensional spacetime and d-dimensional Ricci-flat internal space is considered with a higher-dimensional cosmological constant. The classical cosmology in commutative and Doubly Special Relativity–Generalized Uncertainty Principle (DSR–GUP) contexts is studied and the corresponding exact solutions for negative and positive cosmological constants are obtained. In the positive cosmological constant case, it is shown that unlike the commutative as well as GUP cases, in DSR–GUP case both scale factors of internal and external spaces after accelerating phase will inevitably experience decelerating phase leading simultaneously to a big crunch. This demarcation from GUP originates from the difference between the GUP and DSR–GUP algebras. The important result is that unlike GUP which results in eternal acceleration, DSR–GUP at first generates acceleration but prevents the eternal acceleration at late-times and turns it into deceleration

    A new method for critical path method with fuzzy processing time

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    Critical path method plays an important role on managing medium to large-scale problems. It is often difficult to determine the critical path for different reasons such as the existing uncertainties in processing tasks. One alternative to handle the uncertainty associated with the processing time is to use fuzzy techniques. We present a new method to calculate the critical path method when the processing times follow trapezoidal fuzzy numbers. The proposed model of this paper does not use any defuzzification technique to find the final processing time. The implementation of the proposed model is compared with other techniques using a well-known example from the literature

    Influence of genotype and plant growth regulator on somatic embryogenesis in rapeseed (Brassica napus L.)

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    Two genotypes of Brassica napus species (Talayeh and RGS003) and the explants segment (hypocotyls and cotyledon) were tested for their potential to produce somatic embryos in in vitro condition. The effect of genotype, different explants and also different concentrations of plant growth regulators (PGRs) including: -naphthalene acetic acid (NAA), 2,4-Dichlorophenoxy acetic acid (2,4-D), 6-benzyl amino purine (BAP), were investigated. The basal medium was Murashige and Skoog (MS)supplemented with 2% sucrose and 1% agar. Explants plated on different callus induction medium and each 4 week was subculture in the same medium. The results showed that ‘Talayeh’, in terms of regeneration, had significant difference with RGS003 and produce more somatic embryos. In this genotype, modified MS medium containing 2% sucrose, 6 mg l-1 sodium chloride (NaCl), 3 mg l-1 BAP, 2 mg l-1 NAA and 2 mg l-1 2,4-D was the most efficient medium for somatic embryogenesis in ‘Talayeh’and also, hypocotyl explants were found to be more suitable than cotyledon for somatic embryogenesis

    Human Brucellosis: Risks and Prevalence among Iranian Blood Donors Residing in Endemic Areas

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    Background: Brucellosis is a common zoonotic infection worldwide. Transmission can be occasionally observed via transfusion or transplantation. This study was designed to survey the seroprevalence of anti-Brucella antibody in blood donors in different endemic provinces. Materials and Methods: A total of 14,706 blood donors from the 5 most prevalent provinces were studied by standard tube agglutination (STA) and any positive subjects were further confirmed by 2-mercaptoethanol agglutination test (2-ME). Significant titres were 80 for STA and 40 for 2-ME. Result: A total of 63 (0.43) serum samples were STA-positive. Of these, the 2-ME test was reactive in 42 samples. The 2-ME test was reactive in 31 samples with a low titre. However, concomitant STA �80 and the titre of �40 for the 2-ME test were found in 11 subjects (0.075), mostly resident in urban areas. Exposure to manure products was identified as a significant risk factor (p = 0.0128). Conclusion: The observed data show a somewhat noticeable prevalence among Iranian blood donors, bringing attention to the importance of pre-donation screening via a questionnaire which supplies answers about occupational history, and any history of exposure or past infections. Further studies to evaluate the frequency and related risk factors in certain populations, in conjunction with implementing stricter regulations in blood donor selection in endemic areas, may be necessary. © 2019 S. Karger AG, Basel. All rights reserved

    Human Brucellosis: Risks and Prevalence among Iranian Blood Donors Residing in Endemic Areas

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    Background: Brucellosis is a common zoonotic infection worldwide. Transmission can be occasionally observed via transfusion or transplantation. This study was designed to survey the seroprevalence of anti-Brucella antibody in blood donors in different endemic provinces. Materials and Methods: A total of 14,706 blood donors from the 5 most prevalent provinces were studied by standard tube agglutination (STA) and any positive subjects were further confirmed by 2-mercaptoethanol agglutination test (2-ME). Significant titres were 80 for STA and 40 for 2-ME. Result: A total of 63 (0.43) serum samples were STA-positive. Of these, the 2-ME test was reactive in 42 samples. The 2-ME test was reactive in 31 samples with a low titre. However, concomitant STA �80 and the titre of �40 for the 2-ME test were found in 11 subjects (0.075), mostly resident in urban areas. Exposure to manure products was identified as a significant risk factor (p = 0.0128). Conclusion: The observed data show a somewhat noticeable prevalence among Iranian blood donors, bringing attention to the importance of pre-donation screening via a questionnaire which supplies answers about occupational history, and any history of exposure or past infections. Further studies to evaluate the frequency and related risk factors in certain populations, in conjunction with implementing stricter regulations in blood donor selection in endemic areas, may be necessary. © 2019 S. Karger AG, Basel. Copyright: All rights reserved

    The comparative study of the streptococcinum, Hepar sulfur, Rosmarinus officinalis and erythromycin effects on cultured rainbow trout (Oncorhynchus mykiss) with experimental streptococcusis.

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    The comparative study of the streptococcinum, Hepar sulfur, Rosmarinus officinalis and erythromycin effects on cultured rainbow trout (Oncorhynchus mykiss) with experimental streptococcosis Homeopathy is one of alternative medicines that is very useful for soul and body diseases with accurate prescription. The goal of this study was “survey of the effects of homeopathic remedies. There is not any more research about homeopathy on aquatics in the world especially in Iran, thus Some research about the effects of homeopathy on aquatics is needed. In this study, the effects of streptococcinum, Hepar sulfure, Rosmarinus officinalis(homeopathic remedies) and erythromycin in cultured rainbow trout, with experimental streptococcosis, also the mortality, were compared. There was 6 treatment and 2 reviews in 300 liter tanks that each of treatment contained 40 juvenile rainbow trout with 25±5 gr arrange weight. Treatment 1: contained of erythromycin. Treatment 2: Streptococcinum C30. Treatment 3: Rosmarinus officinalis Q. Treatment 4: Hepar sulfur C30 . Treatment 5:(control treatment )without any injection and any therapy. Treatment 6: (positive control treatment) with injection but without any therapy. Daily estimation of the water temperature, oxygen, pH and salinity and some other chemical factors. Tretment 1 had significance with the other treatments. Survival percent in treatments and their analysis showed that treatment 4(Hep-s) had significance (p<0.05) with treatment 3(Ros-off) and its survival percent is more than the other homeopathic remedies. Erythromycin is chemical drug and has many side effects but Hep-s has not any side effect and is an natural remedy for Streptococcosis in homeopathy. Thus we offer the Hep-s to cure the streptococcosis but some research with disk diffusion test about the different doses of Hep-s is needed. Daily survey of clinical symptoms such as hemorrhages in the external organs, Under eyes, under skin, under fins and gills, hemorrhages and exophthalmos, were the most symptoms. Important pathological symptoms were: necrosis, hyperplasia and melanosis in branches, liver and kidneys, hemorrhages in heart, kidneys and in visceral tissues. According to the survival results, there was significant difference between the treatment 1 and the other treatments (p<0.05). Also there was significant difference between treatment 3, treatment 4 and treatment 2(p<0.05), this difference is due to the high dose(Q) of R.officinalis, while the two other homeopathic remedies were in a moderated dose (C30), 30× 100 diluted dose. Survival percent of treatment 4(Hep-s) was more than the other homeopathic remedies and was related to erythromycin. Erythromycin is chemical medicine and has many side effects, while Hepar sulfur has not any side effects if the prescription would be accurate. Hep-s is suggested with disk diffusion tests for relief the symptoms of streptococcosis

    Derivative UV/Vis spectroelectrochemistry in a thin-layer regime: deconvolution and simultaneous quantification of ascorbic acid, dopamine and uric acid

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    In this work, UV/Vis spectroelectrochemistry (SEC), in a thin-layer regime and parallel configuration, is selected to solve a complex mixture that contains dopamine (DA), ascorbic acid (AA) and uric acid (UA). These molecules, like many other biological compounds, are assuming a highly important place in analytical and biomedical fields due to the fundamental role that they play in human metabolism. In addition, low or high levels of these compounds are associated with diseases such as Parkinson’s disease. For this reason, the quantification of these biomolecules is becoming increasingly critical. However, some drawbacks must be overcome, because the three molecules coexist in the human body, and the species are subject to mutual interference. In fact, they are all oxidized at similar potentials, and their UV/Vis absorption bands overlap, greatly complicating their quantification. For this reason, derivative SEC together with suitable chemometric tools such as PARAFAC are proposed to solve this complex matrix. This technique allows us to separate the contribution of each of these molecules present in a sample and to quantify all of them, achieving high resolution and reproducibility. Besides, detection limits at the micromolar level are achieved for DA, AA and UA in mixture solutions. This work thus demonstrates the great potential for derivative potentiodynamic SEC combined with the appropriate chemometric tools in solving complex mixtures, a field where SEC is still taking the first steps.Ministerio de Economía y Competitividad (Grants CTQ2017-83935-RAEI/ FEDER, UE), Junta de Castilla y León (Grant BU297P18) and Ministerio de Ciencia, Innovación y Universidades (RED2018-102412- T). F.O. is grateful for the contract funded by Junta de Castilla y León, the European Social Fund and the Youth Employment Initiative. J.G.R. thanks theMinisterio de Economía y Competitividad for his postdoctoral contract (CTQ2017-83935-R AEI/FEDER, UE)
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