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111.
Carcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical techniques and applications of developed techniques in a variety of matrices.   相似文献   
112.
In this paper we define odd dimensional unitary groups U2n+1(R,Δ). These groups contain as special cases the odd dimensional general linear groups GL2n+1(R) where R is any ring, the odd dimensional orthogonal and symplectic groups O2n+1(R) and Sp2n+1(R) where R is any commutative ring and further the first author's even dimensional unitary groups U2n(R,Λ) where (R,Λ) is any form ring. We classify the E-normal subgroups of the groups U2n+1(R,Δ) (i.e. the subgroups which are normalized by the elementary subgroup EU2n+1(R,Δ)), under the condition that R is either a semilocal or quasifinite ring with involution and n3. Further we investigate the action of U2n+1(R,Δ) by conjugation on the set of all E-normal subgroups.  相似文献   
113.
Experimental and theoretical studies are made of the consequences of a nonlinear coupling process between pump rf waves and interchange modes in mirror plasmas. It is demonstrated that the interchange-stable operation window exists depending on the applied rf power and gamma=omega(0)/Omega(i), where omega(0) (Omega(i)) is the angular frequency of the applied rf wave (ion cyclotron frequency). Results are shown that the nonlinear wave coupling process gives rise to the operation window near the resonance (gamma approximately equal to 1), which is elucidated by theoretical analyses combined with full rf wave simulations.  相似文献   
114.
The present work reports the effect of light on the open-circuit voltage of a photoelectrochemical cell (PEC) formed of TiO2 photoanode, Pt cathode and Na2SO4 (0.35 M) aqueous solution as electrolyte. The studies included the measurements of the electromotive force (EMF) during the light-off and light-on cycles for the PEC involving photoanode that was made of both oxidised and reduced TiO2 thin films. These specimens were formed by oxidation of the titanium metal at high and low oxygen activities. This was achieved by the imposition of the gas phase of two different compositions, including air, p(O2) = 21 kPa, and the hydrogen–water vapour mixture, p(O2) = 10-10p({\rm O}_2) = 10^{-10} Pa, at 1,123 K and subsequent cooling to room temperature. The determined data indicate that the PEC formed of the oxidised specimen exhibits larger EMF and a substantially better stability in time. It is, therefore, concluded that the TiO2 obtained in air exhibits superior performance-related properties compared to the reduced specimen. The obtained experimental EMF data are considered in terms of the effect of light on the reactivity of TiO2 with oxygen and water and the related charge transfer.  相似文献   
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This paper presents a game theoretic model that analyzes resource allocation strategies against an adaptive adversary to secure cargo container transportation. The defender allocates security resources that could interdict an unauthorized weapon insertion inside a container. The attacker observes the defender’s security strategy and chooses a site to insert the weapon. The attacker’s goal is to maximize the probability that the weapon reaches its target. The basic model includes a single container route. The results in the basic model suggest that in equilibrium the defender should maintain an equal level of physical security at each site on the cargo container’s route. Furthermore, the equilibrium levels of resources to interdict the weapon overseas increase as a function of the attacker’s capability to detonate the weapon remotely at a domestic seaport. Investment in domestic seaport security is highly sensitive to the attacker’s remote detonation capability as well. The general model that includes multiple container routes suggests that there is a trade-off between the security of foreign seaports and the physical security of sites including container transfer facilities, container yards, warehouses and truck rest areas. The defender has the flexibility to shift resources between non-intrusive inspections at foreign seaports and physical security of other sites on the container route. The equilibrium is also sensitive to the cost effectiveness of security investments.  相似文献   
117.
Several approaches have been proposed for evaluating information in expected utility theory. Among the most popular approaches are the expected utility increase, the selling price and the buying price. While the expected utility increase and the selling price always agree in ranking information alternatives, Hazen and Sounderpandian [11] have demonstrated that the buying price may not always agree with the other two. That is, in some cases, where the expected utility increase would value information A more highly than information B, the buying price may reverse these preferences. In this paper, we discuss the conditions under which all these approaches agree in a generic decision environment where the decision maker may choose to acquire arbitrary information bundles.  相似文献   
118.
Editorial     
Anthony Bak 《K-Theory》1989,3(3):197-198
  相似文献   
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