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Let (Formula presented.) and (Formula presented.) denote the group of rth roots of unity, the set of all (Formula presented.) matrices over (Formula presented.), the (Formula presented.) matrix with all entries 1 and the (Formula presented.) matrix with (Formula presented.) in the (1, 1)-entry and 1 elsewhere, respectively. Let (Formula presented.). Wang proved that (Formula presented.) if and only if A can be obtained from (Formula presented.) by a finite sequence of elementary operations. In this paper, we generalize this result for matrices over (Formula presented.) by showing that the absolute value of permanent function achieves the maximum value, n!, if and only if A is the matrix... 

Let μr, Ωn(μr), Jn and Jn(e2Πi/r) denote the group of rth roots of unity, the set of all n × n matrices over μr, the n × n matrix with all entries 1 and the n × n matrix with e2Πi/r in the (1, 1)-entry and 1 elsewhere, respectively. Let A ∈ Ωn (μ2). Wang proved that (A) = n ! if and only if A can be obtained from Jn by a finite sequence of elementary operations. In this paper, we generalize this result for matrices over μr by showing that the absolute value of permanent function achieves the maximum value, n!, if and only if A is the matrix obtained from Jn by the certain elementary operations. Also, we prove that if α= max{|per(A)|; AϵΩn(µr ), A (Formula presented.) Jn}, then... 

There seems to be a tension between determinism and moral responsibility such that, if determinism is true then perhaps we cannot be responsible for our actions. In his On What Matters, Derek Parfit tried to find a way to dissolve this tension through discussing a Kantian argument about the noumenal world. In recent years Parfit’s argument has received some criticism, which has sought to undermine his argument while also making a variety of different claims about his actual views on this issue. In this paper, I argue that Parfit’s argument requires modification: and my proposals not only promise to make his argument clearer, but can also be used to answer some of his critics. I conclude by... 

There seems to be a tension between determinism and moral responsibility such that, if determinism is true then perhaps we cannot be responsible for our actions. In his On What Matters, Derek Parfit tried to find a way to dissolve this tension through discussing a Kantian argument about the noumenal world. In recent years Parfit’s argument has received some criticism, which has sought to undermine his argument while also making a variety of different claims about his actual views on this issue. In this paper, I argue that Parfit’s argument requires modification: and my proposals not only promise to make his argument clearer, but can also be used to answer some of his critics. I conclude by... 

Let μm be the group of mth roots of unity. In this paper it is shown that if m is a prime power, then the number of all square matrices (of any order) over μm with non-zero constant determinant or permanent is finite. If m is not a prime power, we construct an infinite family of matrices over μm with determinant one. Also we prove that there is no n×n matrix over μp with vanishing permanent, where p is a prime and n = pα-1. © 2003 Elsevier Inc. All rights reserved  

A glassy carbon electrode was coated with a thin layer of multi-walled carbon nanotubes and subsequently was electro-polymerized with polypyrrole. The prepared electrode was used for the voltammetric determination of olanzapine (OLZ). The peak current of OLZ increases remarkably on the surface of the modified electrode. This is due to the large increase in the microscopic area of the electrode surface along with the strong adsorption of OLZ on the surface of the electrode. The film modifier was characterized by scanning electron microscopy, atomic force microscopy and cyclic voltammetry techniques. Experimental variables, such as deposited amount of nanotube suspension, pH of the supporting... 

As a novel and highly sensitive sensor, three-dimensional gold nanoelectrode ensembles (3D GNE) prepared by gold deposition inside the parallel pores of a porous template have been successfully applied in electrochemical determination experiments. In this study, we report on the fabrication of 3D gold nanotubes (GNT) and their application in determination of Hg (II) in water. The morphology and crystal structure of the 3D GNT were characterized by field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD), respectively. The sensitivity of the fabricated electrode towards Hg (II) was examined using anodic stripping voltammetry (ASV) as a powerful technique in... 

A simple ultrasound-assisted dispersive micro-solid phase extraction method based on graphene-oxide (GO) nanosorbents (UAD-μ-SPE), followed by high performance liquid chromatography-ultraviolet detection (HPLC-UV) was developed for the simultaneous determination of theophylline, theobromine and caffeine in different infusion tea samples. GO was synthesized by Hummers method and characterized with field emission-scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) spectroscopy. The GO sorbent was dispersed in the sample solution with the assistance of ultrasound to enhance adsorption and desorption performance and rates. The main parameters... 

The electrochemical response of sodium levo-thyroxin (T4) at the surface of an edge plane pyrolytic graphite (EPPG) electrode is investigated using cyclic voltammetric technique in the presence of 0.1M HCl as supporting electrolyte. T4 underwent totally irreversible oxidation at this system and a well-defined peak at 821mV was obtained. Compared to the signals obtained in the optimized conditions at bare glassy carbon and carbon paste electrodes, the oxidation current of T4 at an EPPG electrode was greatly enhanced. The electrochemical process of T4 was explored and the experimental conditions were optimized. The oxidation peak current represented a linear dependence on T4 concentration from... 

The raising trend both in violent and property crime are of major concern in Iran. Using a panel data modeling (province wide), the paper provides an econometrics assessment of the relationship between crime against properties and violent crimes as functions of deterrent, social, economic and demographic factors in Iran, in the framework of Becker-Ehrlich crime supply theory. The findings indicate that, although deterrence hypothesis is not confirmed for burglary and assault, it explains the variations of murders and threats. Economic factors play key role in burglary and threat explanation, but they do not affect willful murders, however, Literacy explains both murders and threats. Average... 

A simple and effective procedure is proposed for spectrophotometric determination of catecholamines; Dopamine (1), L-Dopa (2) and Adrenaline (3). It was found that the reduction of Ag+ to silver nanoparticles (Ag-NPs) by these catecholamines in the presence of polyvinylpyrrolidone (PVP) as a stabilizing agent produced very intense surface plasmon resonance peak of Ag-NPs. The plasmon absorbance of the Ag-NPs allows the quantitative spectrophotometric detection of the catecholamines. The calibration curves derived from the changes in absorbance at λ = 440 nm were linear with concentration of Dopamine, Levodopa and Adrenaline in the range of 3.2×10-6- 2.0x10-5 M, 1.6x10-7 - 1.0×10-5 M,... 

A complex matrix A is ray-nonsingular if det(XοA) ≠ 0 for every matrix X with positive entries. It is known that the order of a full ray-nonsingular matrix is at most 5 and examples of full n×n ray-nonsingular matrices for n=2, 3, 4 exist. In this note, we describe a property of a special full 5 × 5 ray-nonsingular matrix, if such matrix exists, using the concept of an isolated set of transversals and we obtain a necessary condition for a complex matrix A to be ray-nonsingular. Moreover we give an example of a full 5 × 5 ray-pattern matrix that satisfies all three of the properties given by Lee et al. [Discrete Math. 216 (2000) 221-233]. The notion of Q-ray nonsingularity is also introduced.... 

Salicylate selective electrodes based on oxo(phthalocyanato)-vanadium(IV) [VO(Pc), vanadyl phthalocyanine] and oxo(phthalocyanato)molybdenum(IV) [MoO(Pc), molybdenyl phthalocyanine] are described. The electrodes were prepared by incorporating the ionophores into plasticized poly(vinyl chloride) membranes, which were directly coated on the surface of graphite electrodes. The resulting electrodes demonstrate Nernstian responses over a wide linear range (10-7-10-1 M) salicylate. The electrodes have a fast response time, submicromolar detection limit, and could be used over the pH range of 6-9. The proposed sensors revealed selectivity for salicylate over a number of common inorganic and organic... 

Parameter extraction of the five-parameter single-diode model of solar cells and modules from experimental data is a challenging problem. These parameters are evaluated from a set of nonlinear equations that cannot be solved analytically. On the other hand, a numerical solution of such equations needs a suitable initial guess to converge to a solution. This paper presents a new set of approximate analytical solutions for the parameters of a five-parameter single-diode model of photovoltaic (PV) cells and modules. The proposed solutions provide a good initial point which guarantees numerical analysis convergence. The proposed technique needs only a few data from the PV current-voltage... 

The Blaschke-Petkantschin formula is a geometric measure decomposition of the q-fold product of Lebesgue measure on ℝ n. Here we discuss another decomposition called polar decomposition by considering ℝ n× ×ℝ n as n×k and using its polar decomposition. This is a generalisation of the Blaschke-Petkantschin formula and may be useful when one needs to integrate a function g:ℝ n××ℝ n→ℝ with rotational symmetry, that is, for each orthogonal transformation O,g(O(x1),O(xk))=g(x1,xk) . As an application we compute the moments of a Gaussian determinant. Copyright  

The currently available commercial motion capture systems are constrained by space requirement and thus pose difficulties when used in developing kinematic description of human movements within the existing manufacturing and production cells. The Kinect sensor does not share similar limitations but it is not as accurate. The proposition made in this article is to adopt the Kinect sensor in to facilitate implementation of Health Engineering concepts to industrial environments. This article is an evaluation of the Kinect sensor accuracy when providing three dimensional kinematic data. The sensor is thus utilized to assist in modeling and simulation of worker performance within an industrial... 

Risperidone (RIS), one of the typical antipsychotics drugs, originally approved to be used for the mental illness treatment, especially schizophrenia, bipolar disorder, autism and major depression. In the present study, different carbon nanostructures including functionalized multi-walled carbon nanotubes (F-MWCNTs), carbon nanoparticles, nanodiamond-graphite and reduced graphene oxide were employed for modification of the surface of glassy carbon electrode (GCE) for ultrasensitive detection of RIS. The most significant increase in the anodic peak current of RIS was observed on F-MWCNTs-modified electrode (compared to the other modified electrodes and bare GCE). The influence of different... 

Development of visual detection methods regarding water pollutants can effectively facilitate water resource monitoring programs. A wide color-varying ratiometric approach has been developed for sensitive determination of sulfide by mixing orange emissive glutathione stabilized gold nanoclusters (AuNCs) and blue emissive urea stabilized carbon dots (CDs) in an appropriate ratio. Under a single excitation wavelength of 365 nm, the ratiometric fluorescence (RF) probe exhibited two distinct emission bands at 452 and 607 nm corresponding to CDs and AuNCs, respectively. Owing to the high affinity of sulfide ions to AuNCs in alkaline medium, the fluorescence (FL) of AuNCs was turned-off while the...