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41.
Kalanithi Nesaretnam Dashayini Mahalingam Ammu Kutty Radhakrishnan Robert Premier 《European Journal of Lipid Science and Technology》2010,112(5):531-536
Palm oil is a rich source of vitamin E. The tocotrienol‐rich fraction (TRF) extracted from palm oil contain 70% tocotrienols and 30% tocopherols. The effect of TRF supplementation on the immune modulation was evaluated in 6‐wk‐old female BALB/c mice immunized with ovalbumin (OVA) adjuvanted with alum. Mice in control and experimental groups were immunized subcutaneously (s.c.) on days 14 and 28 with a single dose of 50 µg OVA. The mice in the experimental group were orally gavaged daily with 1 mg of TRF from palm oil while those in the control group received carrier oil. The results show that mice in the experimental group produced significantly (p<0.05) higher levels of interferon‐gamma (IFN‐γ) compared to the control group. There was no significant (p>0.05) difference in the levels of interleukin‐4 (IL‐4) produced between the control and experimental animals. Lymphocyte proliferation in response to mitogen or OVA stimulation was significantly (p<0.05) higher in splenocytes derived from the TRF supplemented mice compared to control mice. These findings show that daily supplementation of palm TRF can induce a strong cell‐mediated immune response, i.e., T‐helper‐1 (Th1) response, which would be beneficial to fight viral infections and cancer. 相似文献
42.
We define a new relation on words by a finite series of insertions and/or deletions of palindromic subwords. In particular
we concentrate on insertion or deletion of Watson–Crick palindromes. We show that the new relation ∼θ is, in fact, an equivalence relation where θ is any arbitrary antimorphic involution that is not the identity on the letters
of the alphabet. We also show that the set of all θ-palindromic free words defined in (Daley et al. in preparation) is ∼θ-independent. Using the relation we define a new subclass of primitive words which we call as ∼θ-primitive words and show that the class of all ∼θ-primitive words is closed under circular permutations. We also define ∼θ-conjugates and ∼θ-commutativity and study the properties of such words and show that they are similar to that of conjugate words and words
that commute. 相似文献
43.
Ionic conductivity studies in the temperature range 304–373 K for PVC---Li2SO4---dibutylphthalate polymer electrolyte systems are reported and discussed. Poly(vinylchloride) (PVC) has an electrical conductivity 10−8 S cm−1. The prepared films were studies by X-ray diffraction, Fourier transformation infrared, scanning electron microscopy and thermal analysis. The temperature dependence of the conductivity of the polymer films obeys the Vogel–Tammann–Fulcher relation. 相似文献
44.
ISO TS 19700 describes a test method for the generation of fire effluent and the identification and measurement of its constituent combustion products. The method has been previously accepted as a British Standard (BS 7990:2003) and as an IEC Standard (IEC 60695‐7‐50), which involves the decomposition of materials or products under various decomposing conditions occurring in different types and stages of real fires. It uses a moving test specimen and a tube furnace at different temperatures and air flow rates as the fire model. Simulations of flow and combustion conditions inside the tube (Purser) furnace were carried out and validated with the measurements. The objective of the present study is to demonstrate the validity of using computational fluid dynamics (CFD)‐based fire field modelling techniques to predict the fire environment inside the tube furnace. These numerical investigations are also used to verify critical experimental operating parameters that affect the performance of the tube furnace and understand the modus operandi of the tube furnace toxicity method. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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47.
V. Mahalingam M. Tan P. Munusamy J. B. Gilroy M. Raudsepp F. C. J. M. van Veggel 《Advanced functional materials》2007,17(17):3462-3469
In this article we demonstrate the synthesis of Eu2+‐doped GaN/SiO2 nanocomposites using a simple solid state reaction and their use in light‐emitting devices. The nanocomposite exhibits a bright blue luminescence when excited in the UV region (quantum yield = 23 %). The origin of the blue emission is attributed to the presence of europium ions in the +2 oxidation state in the GaN/SiO2 nanocomposites. Analysis of the EPR spectrum of europium‐doped GaN/SiO2 nanocomposites confirms the existence of Eu2+ in the nanocomposites. Various control experiments show that the blue emission arises from these europium ions and that the interface of GaN and silica plays a crucial role. The Eu2+‐doped GaN/SiO2 nanocomposite also exhibits a bright blue electroluminescence. Furthermore, the nanocomposites can be coated with a polymer to tune their dispersibility in organic medium. 相似文献
48.
In this paper, we present novel multi-criteria query optimization techniques for performing query optimization in databases, such as multimedia and web databases, which rely on imperfect access mechanisms and top-k predicates. We present an optimization model that (1) takes into account different binding patterns associated with query predicates, (2) considers the variations in the expected query result sizes as a function of query execution plans, and (3) considers the expected result qualities of the execution orders. We address the complexity and the well-known NP-complete nature of the query optimization problem by adaptively reducing the granularity of the search space. For this purpose, unlike the data histograms which capture the data distribution, we propose opt-histograms that capture the distribution of sub-query-plan values over many optimization tasks. 相似文献
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50.
Barium titanate (BaTiO3) thin films doped with Mn (0.1–1.0 at%) were prepared by r.f. magnetron sputtering technique. Oxygen/argon (O2/Ar) gas ratio is found to influence the sputtering rate of the films. The effects of Mn doping on the structural, microstructural
and electrical properties of BaTiO3 thin films are studied. Mn-doped thin films annealed at high temperatures (700 °C) exhibited cubic perovskite structure.
Mn doping is found to reduce the crystallization temperature and inhibit the grain growth in barium titanate thin films. The
dielectric constant increases with Mn content and the dielectric loss (tan δ) reveals a minimum value of 0.0054 for 0.5% Mn-doped
BaTiO3 films measured at 1 MHz. The leakage current density decreases with Mn doping and is 10−11 A/cm−2 at 6 kV/cm for 1% Mn-doped thin films. 相似文献