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Open access

Erol Kam, Iskender A. Reyhancan and Recep Biyik

Abstract

Depending on the neutron energy used, neutron radiography can be generally categorized as fast and thermal neutron radiography. Fast neutron radiography (FNR) with neutron energy more than 1 MeV opens up a new range of possibilities for a non-destructive examination when the inspected object is thick or dense. Other traditional techniques, such as X-ray, gamma ray and thermal neutron radiography, do not meet penetration capabilities of FNR in this area. Because of these distinctive features, this technique is used in different industrial applications such as security (cargo investigation for contraband such as narcotics, explosives and illicit drugs), gas/liquid flow and mixing and radiography and tomography of encapsulated heavy shielded low Z compound materials. The FNR images are produced directly during exposure as neutrons create recoil protons, which activate a scintillator screen, allowing images to be collected with a computer-controlled charge-coupled device camera. Finally, the picture can be saved on a computer for image processing. The aim of this research was to set up a portable FN R system and to test it for use in non-destructive testing of different composite materials. Experiments were carried out by using a fast portative neutron generator Thermo Scientific MP 320.

Open access

Faisal Al-Otaibi

Abstract

There are several limited approaches to treat epilepsy in hospitals, for example, using medicines, surgery, electrical stimulation and dietary interventions. Despite the availability of all these new and old approaches, seizure is particularly difficult to manage. The quest for new antiepileptic molecules with more specificity and less CNS toxicity continues for medicinal chemists until a new and ideal drug arrives. This review covers new antiseizure molecules of different chemical classes, the exact mode of action of which is still unidentified. Newer agents include sulfonamides, thiadiazoles, semi- and thiosemicarbazones, pyrrolidine-2,5-diones, imidazoles, benzothiazoles and amino acid deriva tives. These new chemical entities can be useful for the design and development of forthcoming antiseizure agents.

Open access

Anetta Szynal-Liana and Iwona Włoch

Abstract

The hybrid numbers are generalization of complex, hyperbolic and dual numbers. In this paper we consider special kinds of hybrid numbers, namely the Jacobsthal and the Jacobsthal-Lucas hybrid numbers and we give some their properties.

Open access

Dorota Bród

Abstract

In this paper we present a new one parameter generalization of the classical Pell numbers. We investigate the generalized Binet’s formula, the generating function and some identities for r-Pell numbers. Moreover, we give a graph interpretation of these numbers.

Open access

Nadeem ur Rehman, Radwan M. Al-omary and Najat Mohammed Muthana

Abstract

Let R be a prime ring with center Z(R). A map G : RR is called a multiplicative (generalized) (α, β)-derivation if G(xy)= G(x)α(y)+β(x)g(y) is fulfilled for all x; yR, where g : RR is any map (not necessarily derivation) and α; β : RR are automorphisms. Suppose that G and H are two multiplicative (generalized) (α, β)-derivations associated with the mappings g and h, respectively, on R and α, β are automorphisms of R. The main objective of the present paper is to investigate the following algebraic identities: (i) G(xy) + α(xy) = 0, (ii) G(xy) + α(yx) = 0, (iii) G(xy) + G(x)G(y) = 0, (iv) G(xy) = α(y) ○ H(x) and (v) G(xy) = [α(y), H(x)] for all x, y in an appropriate subset of R.

Open access

Paweł Gładki

Abstract

In this work we generalize the results of [9] to the higher level case: we define n-th root selections in fields of characteristic ≠ 2, that is subgroups of the multiplicative group of a field whose existence is equivalent to the existence of a partial inverse of the xxn function, provide necessary and sufficient conditions for such a subgroup to exist, study their existence under field extensions, and give some structural results describing the behaviour of maximal n-th root selection fields.

Open access

Karolina Słoczyńska, Agnieszka Gunia-Krzyżak, Paulina Koczurkiewicz, Katarzyna Wójcik-Pszczoła, Dorota Żelaszczyk, Justyna Popiół and Elżbieta Pękala

Abstract

Determination of metabolic profiles of new chemical entities is a key step in the process of drug discovery, since it influences pharmacokinetic characteristics of therapeutic compounds. One of the main challenges of medicinal chemistry is not only to design compounds demonstrating beneficial activity, but also molecules exhibiting favourable pharmacokinetic parameters. Chemical compounds can be divided into those which are metabolized relatively fast and those which undergo slow biotransformation. Rapid biotransformation reduces exposure to the maternal compound and may lead to the generation of active, non-active or toxic metabolites. In contrast, high metabolic stability may promote interactions between drugs and lead to parent compound toxicity. In the present paper, issues of compound metabolic stability will be discussed, with special emphasis on its significance, in vitro metabolic stability testing, dilemmas regarding in vitro-in vivo extrapolation of the results and some aspects relating to different preclinical species used in in vitro metabolic stability assessment of compounds.

Open access

Yufang Ni, Zhixian Cao and Qingquan Liu

Abstract

A 2D hydrodynamic (labeled as CAR) model has been proposed in a rectangular Cartesian coordinate system with two axes within the horizontal plane and one axis along the vertical direction (global coordinates), considering the effects of bed slope on both pressure distribution and bed shear stresses. The CAR model satisfactorily reproduces the analytical solutions of dam-break flow over a steep slope, while the traditional Saint-Venant Equations (labeled as SVE) significantly overestimate the flow velocity. For flood events with long duration and large mean slope, the CAR and the SVE models present distinguishable discrepancies. Therefore, the proposed CAR model is recommended for applications to real floods for its facility of extending from 1D to 2D version and ability to model shallow-water flows on steep slopes.

Open access

Hoger Ghahramani and Saman Sattari

Abstract

Let Alg 𝒩 be a nest algebra associated with the nest 𝒩 on a (real or complex) Banach space 𝕏. Suppose that there exists a non-trivial idempotent PAlg 𝒩 with range P (𝕏) ∈ 𝒩, and δ : Alg 𝒩 → Alg 𝒩 is a continuous linear mapping (generalized) left derivable at P, i.e. δ (ab) = (b) + (a) (δ (ab) = (b) + (a) − baδ(I)) for any a, bAlg 𝒩 with ab = P, where I is the identity element of Alg 𝒩. We show that is a (generalized) Jordan left derivation. Moreover, in a strongly operator topology we characterize continuous linear maps on some nest algebras Alg 𝒩 with the property that δ (P ) = 2 (P ) or δ (P ) = 2P δ (P ) − Pδ (I) for every idempotent P in Alg 𝒩.

Open access

Jean-Paul Mavoungou

Abstract

Let F be an endofunctor of a category C. We prove isomorphism theorems for F -coalgebras under condition that the underlying category C is exact; that is, regular with exact sequences. Also, F is not assumed to preserve pullbacks.