Numerical Investigation of Drug Delivery to Cancerous Solid Tumors by Magnetic Nanoparticles Using External Magnet

Chemotherapy as one of the most utilized cancerous tumor treatment methods introduces undesired side effects due to penetrating toxic drugs into the healthy organs. Delivery of anticancer therapeutic agents to solid tumors is also problematic. The purpose of current study is to investigate the penetration of magnetic drug carriers (MDCs) within the cancerous solid tumor tissue under the influence of external magnet. Capillary wall and tumor tissue is modeled as a saturated porous media. In order to solve the coupled governing equations, mass, momentum and concentration, an in-house finite volume-based code is developed and utilized. Results show the penetration of MDCs into the tumor in the absence of magnetic field is minimal and is limited to the surface of the tumor. On the other hand, under the influence of external magnet the penetration of MDCs within the tumor increases exponentially. They also penetrate deep into the tumor and cover the entire tumor which increase the effectivity and decrease the side effect of the treatment.     

The impact of customer behavior models on revenue management systems

Computational Management Science - Revenue management (RM) can be considered an application of operations research in the transportation industry. For these service companies, it is a difficult...     

Gliclazide as novel carrier in construction of PVC-based La(III)-selective membrane sensor

A PVC-based sensor for La³⁺ ions based on N-[hexahydrocyclopentapyrol-2((1H)yl)amino]carbonyl]-4-methyl benzene sulfonamide (gliclazide) as a novel carrier was prepared. The electrode exhibits a Nernstian response for La³⁺ over a wide concentration range (1.0×10⁻¹-1.0×10⁻⁶ M) with a slope of 20.1 mV per decade. The limit of detection is 8.0×10⁻⁷ M. The sensor has a very short response time (<15 s) and a useful working pH range of 4.0-8.0. The proposed membrane sensor shows excellent discriminating ability towards La³⁺ ions with regard to several alkali, alkaline earth, transition and heavy metal ions. The electrode was successfully applied for determination of La³⁺ in binary mixtures.     

Novel ferrocene modified poly(amide ether amide)s and investigation of physical and thermal properties

A new diamine containing ferrocene group with preformed ether and amide units was prepared via reaction of 1,1′-ferrocenedicarbonyl chloride with two moles of 2,6-bis(5-amino-1-naphthoxy)pyridine. Polycondensation reactions of the prepared diamine with different aromatic and aliphatic diacid chlorides in the presence of trimethylchlorosilane (TMSCl) resulted in preparation of novel ferrocene modified poly(amide ether amide)s. The monomer and polyamides were characterized and the effect of trimethylchlorosilane (TMSCl) as activating agent on the polymerization reaction was studied. The physical and thermal properties of the polyamides including inherent viscosity, solubility, thermal stability and behavior, flame-retardancy and crystallinity of the polymers were studied. The polymers showed good thermal stability and flame-retardancy, and also improved solubility in polar aprotic solvents.     

A review of recent methods for the determination of ranges of feasible solutions resulting from soft modelling analyses of multivariate data

Soft modelling or multivariate curve resolution (MCR) are well-known methodologies for the analysis of multivariate data in many different application fields. Results obtained by soft modelling methods are very likely impaired by rotational and scaling ambiguities, i.e. a full range of feasible solutions can describe the data equally well while fulfilling the constraints of the system. These issues are severely limiting the applicability of these methods and therefore, they can be considered as the most challenging ones. The purpose of the current review is to describe and critically compare the available methods that attempt at determining the range of ambiguity for the case of 3-component systems. Theoretical and practical aspects are discussed, based on a collection of simulated examples containing noise-free and noisy data sets as well as an experimental example.     

Thermoluminescence characteristics of neodymium-doped silicon dioxide optical fibers subjected to X-ray

In this article, we investigate thermoluminescence properties of Nd³⁺ doped silicon dioxide optical fiber. The samples were exposed to 10 MV X-ray using a linear accelerator. The optical fiber was read out using Harshaw 3500 TLD reader. Nd-doped optical fiber displays a linear TL response for the absorbed dose. The sensitivity of Nd-doped optical fiber is 82.87 nC. mg^–1 Gy^–1, which is more sensitive to the other types of optical fiber. Nd⁺³-doped optical fiber displays clear single glow peak around 180°C. The peak shape method analysis reveals that the peaks obey general order kinetics. The activation energy of Nd-doped optical fiber is found to be nearly 0.5 eV less than TLD-100 (1.6 eV). Z_eff of neodymium-doped silicon dioxide optical fiber is 13.48 that is near to the human bone. All of these TL characteristics indicate that Nd107-doped optical fiber as a potential TL dosimeter, for measuring photon irradiation.     

Impedimetric biosensor based on bimetallic AgPt nanoparticle-decorated carbon nanotubes as highly conductive film surface

Journal of Solid State Electrochemistry - In the present study, an ultrasensitive impedimetric aptasensor for the quantitative detection of diclofenac (DCF) was fabricated based on a novel signal...     

Metabolites from the biodegradation of 1,6‐hexanediol dibenzoate,a potential green plasticizer,by Rhodococcus rhodochrous

Metabolites from the biodegradation of a potential plasticizer 1,6‐hexanediol dibenzoate in the presence of n‐hexadecane as a co‐substrate by the common soil organism Rhodococcus rhodochrous were identified using GC/MS and Fourier transform mass spectroscopy (FTMS) techniques. Trimethylsilylation of compounds from the biodegradation broth permitted detection of the following metabolites: 1‐hexadecyl benzoate, 6‐benzoyloxyhexanoic acid, 4‐benzoyloxybutanoic acid, 6‐benzoyloxyhexan‐1‐ol and benzoic acid. The presence of these metabolites was confirmed by repeating the biodegradation with 1,6‐hexanediol di[²H₅]benzoate, by measurement of their exact masses in FTMS and by comparison with available authentic materials. The results show that biodegradation of 1,6‐hexanediol dibenzoate by R. rhodochrous does not lead to the accumulation of persistent metabolites as has been reported for commercial dibenzoate plasticizers. Copyright © 2009 John Wiley & Sons, Ltd.