51 research outputs found

    The effect of 12 weeks Anethum graveolens (dill) on metabolic markers in patients with metabolic syndrome; A randomized double blind controlled trial

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    Background: The clustering of metabolic abnormalities defined as metabolic syndrome is now both a public health and a clinical problem .While interest in herbal medicine has greatly increased, lack of human evidence to support efficacies shown in animals does exist. This clinical trial study designed to investigate whether herbal medicine, Anethum graveolens (dill) extract, could improve metabolic components in patients with metabolic syndrome. Methods: A double-blind, randomized, placebo-controlled trial using a parallel design was conducted. 24 subjects who had metabolic syndrome diagnostic criteria (update of ATP III) were randomly assigned to either dill extract (n = 12) or placebo (n = 12) for 3 months. Results: Across lipid component of metabolic syndrome, no significant differences in triglyceride (TG) concentration and high density lipoprotein cholesterol were seen between the two groups. However TG improved significantly from baseline (257.0 vs. 201.5p = 0.01) with dill treatment but such a significant effect was not observed in placebo group. Moreover, no significant differences in waist circumference, blood pressure and fasting blood sugar were seen between two groups after 3 months follow up period. Conclusion: In this small clinical trial in patients with metabolic syndrome, 12 weeks of dill extract treatment had a beneficial effect in terms of reducing TG from baseline. However dill treatment was not associated with a significant improvement in metabolic syndrome related markers compared to control group. Larger studies might be required to prove the efficacy and safety of long-Term administration of dill to resolve metabolic syndrome components. © 2012 Mansouri et al.; licensee BioMed Central Ltd

    Evaluation of sesamum gum as an excipient in matrix tablets

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    In developing countries modern medicines are often beyond the affordability of the majority of the population. This is due to the reliance on expensive imported raw materials despite the abundance of natural resources which could provide an equivalent or even an improved function. The aim of this study was to investigate the potential of sesamum gum (SG) extracted from the leaves of Sesamum radiatum (readily cultivated in sub-Saharan Africa) as a matrix former. Directly compressed matrix tablets were prepared from the extract and compared with similar matrices of HPMC (K4M) using theophylline as a model water soluble drug. The compaction, swelling, erosion and drug release from the matrices were studied in deionized water, 0.1 N HCl (pH 1.2) and phosphate buffer (pH 6.8) using USP apparatus II. The data from the swelling, erosion and drug release studies were also fitted into the respective mathematical models. Results showed that the matrices underwent a combination of swelling and erosion, with the swelling action being controlled by the rate of hydration in the medium. SG also controlled the release of theophylline similar to the HPMC and therefore may have use as an alternative excipient in regions where Sesamum radiatum can be easily cultivated

    Quantum Random Oracle Model with Auxiliary Input

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    The random oracle model (ROM) is an idealized model where hash functions are modeled as random functions that are only accessible as oracles. Although the ROM has been used for proving many cryptographic schemes, it has (at least) two problems. First, the ROM does not capture quantum adversaries. Second, it does not capture non-uniform adversaries that perform preprocessings. To deal with these problems, Boneh et al. (Asiacrypt\u2711) proposed using the quantum ROM (QROM) to argue post-quantum security, and Unruh (CRYPTO\u2707) proposed the ROM with auxiliary input (ROM-AI) to argue security against preprocessing attacks. However, to the best of our knowledge, no work has dealt with the above two problems simultaneously. In this paper, we consider a model that we call the QROM with (classical) auxiliary input (QROM-AI) that deals with the above two problems simultaneously and study security of cryptographic primitives in the model. That is, we give security bounds for one-way functions, pseudorandom generators, (post-quantum) pseudorandom functions, and (post-quantum) message authentication codes in the QROM-AI. We also study security bounds in the presence of quantum auxiliary inputs. In other words, we show a security bound for one-wayness of random permutations (instead of random functions) in the presence of quantum auxiliary inputs. This resolves an open problem posed by Nayebi et al. (QIC\u2715). In a context of complexity theory, this implies NPcoNP⊈BQP/qpoly \mathsf{NP}\cap \mathsf{coNP} \not\subseteq \mathsf{BQP/qpoly} relative to a random permutation oracle, which also answers an open problem posed by Aaronson (ToC\u2705)

    Mobile app stores from the user's perspectives

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    YesThe use of smartphones has become more prevalent in light of the boom in Internet services and Web 2.0 applications. Mobile stores (e.g., Apple’s App Store and Google Play) have been increasingly used by mobile users worldwide to download or purchase different kinds of applications. This has prompted mobile app practitioners to reconsider their mobile app stores in terms of design, features and functions in order to maintain their customers’ loyalty. Due to the lack of research on this context, this study aims to identify factors that may affect users’ satisfaction and continued intention toward using mobile stores. The proposed model includes various factors derived from information systems literature (i.e., usefulness, ease of use, perceived cost, privacy and security concerns) in addition to the dimensions of mobile interactivity (i.e. active control, mobility, and responsiveness). The study sets out 13 hypotheses that include mediating relationships (e.g., perceived usefulness mediates the influence of ease of use, active control, responsiveness and mobility; perceived ease of use mediates the influence of active control). As well as outlining the proposed research method, the research contributions, limitations and future research recommendations are also addressed

    Elastic properties of polymer composites reinforced with C60 fullerene and carbon onion: Molecular dynamics simulation

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    In this paper, the elastic properties of polymer nanocomposites reinforced with C60 fullerene and C60@C240 carbon onion are estimated by using a molecular dynamic (MD) simulation. The nanocomposites are constructed by embedding the buckminsterfullerene and the carbon onion into an amorphous polymer matrix with different weight fractions. The poly methyl methacrylate (PMMA) is chosen as the polymer matrix. The results demonstrate that Young's modulus of the composite increases with increasing the weight fractions of the nanoscopic additives, which is consistent with experimental observations. The nanocomposite containing 4 wt% of C60 exhibits Young's modulus of 3.774 GPa that is 24% higher than pure PMMA. In addition, the validity of the present simulation is verified by the comparison with the experimental results

    Molecular dynamics simulations of structural instability of fullerene family under tension force

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    Fullerene molecules are cage-like nanoscopic structures with pentagonal and hexagonal faces. In practical applications such as fullerene-reinforced nanocomposites (FRNCs), these structures may be subjected to tension force. In this research, we employ molecular dynamics (MD) simulation to compute the behaviour and deformation of different fullerene molecules, ranging from C60 to C2000, under tension force. To model the interactions between carbon atoms in the MD simulations, the adaptive intermolecular reactive bond order (AIREBO) force field is used. The displacement–force and the displacement–strain energy curves are obtained. It is observed that a new type of structural instability occurs in the fullerene molecules when the applied tension force increases. This abnormal structural instability in the fullerenes is investigated for the first time in the literature. The critical tensile forces and the corresponding mode shapes are determined for different fullerenes. The results indicate that the critical forces and deformations strongly depend upon the number of carbon atoms

    Combined molecular dynamics–micromechanics methods to predict Young's modulus of fullerene-reinforced polymer composites

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    In this paper, a multiscale method is developed to predict Young's modulus of fullerene-reinforced polymer nanocomposites (FRPNs). Polymethyl methacrylate is chosen as the polymer matrix, while C60 fullerene is considered as the reinforcement. First, molecular dynamics (MD) simulations are conducted to calculate the Young modulus of nanocomposite unit cell with different weight fractions of fullerene. Then, a micromechanics model for a composite with multi-inclusion reinforcements is developed based on the extension of the Mori–Tanaka model and generalized Eshelby's results. Numerical results obtained from the proposed micromechanics model are compared with those calculated from the MD simulations, and good agreement is achieved. In addition, we propose an extension for the Halpin–Tsai model to predict Young's modulus of the FRPNs

    Computational modeling of the effective Young’s modulus values of fullerene molecules: a combined molecular dynamics simulation and continuum shell model

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    Estimating the Young’s modulus of a structure in the nanometer size range is a difficult task. The reliable determination of this parameter is, however, important in both basic and applied research. In this study, by combining molecular dynamics (MD) simulations and continuum shell theory, we designed a new approach to determining the Young’s modulus values of different spherical fullerenes. The results indicate that the Young’s modulus values of fullerene molecules decrease nonlinearly with increasing molecule size and understandably tend to the Young’s modulus of an ideal flat graphene sheet at large molecular radii. To the best of our knowledge, this is first time that a combined atomistic–continuum method which can predict the Young’s modulus values of fullerene molecules with high precision has been reported
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