High Frequency Scattering from Arbitrarily Oriented Dielectric Disks

Calculations have been made of electromagnetic wave scattering from dielectric disks of arbitrary shape and orientation in the high frequency (physical optics) regime. The solution is obtained by approximating the fields inside the disk with the fields induced inside an identically oriented slab (i.e. infinite parallel planes) with the same thickness and dielectric properties. The fields inside the disk excite conduction and polarization currents which are used to calculate the scattered fields by integrating the radiation from these sources over the volume of the disk. This computation has been executed for observers in the far field of the disk in the case of disks with arbitrary orientation and for arbitrary polarization of the incident radiation. The results have been expressed in the form of a dyadic scattering amplitude for the disk. The results apply to disks whose diameter is large compared to wavelength and whose thickness is small compared to diameter, but the thickness need not be small compared to wavelength. Examples of the dependence of the scattering amplitude on frequency, dielectric properties of the disk and disk orientation are presented for disks of circular cross section

A support vector-based interval type-2 fuzzy system

In this paper, a new fuzzy regression model that is supported by support vector regression is presented. Type-2 fuzzy systems are able to tackle applications that have significant uncertainty. However general type-2 fuzzy systems are more complex than type-1 fuzzy systems. Support vector machines are similar to fuzzy systems in that they can also model systems that are non-linear in nature. In the proposed model the consequent parameters of type-2 fuzzy rules are learnt using support vector regression and an efficient closed-form type reduction strategy is used to simplify the computations. Support vector regression improved the generalisation performance of the fuzzy rule-based system in which the fuzzy rules were a set of interpretable IF-THEN rules. The performance of the proposed model was demonstrated by conducting case studies for the non-linear system approximation and prediction of chaotic time series. The model yielded promising results and the simulation results are compared to the results published in the area

A support vector-based interval type-2 fuzzy system

In this paper, a new fuzzy regression model that is supported by support vector regression is presented. Type-2 fuzzy systems are able to tackle applications that have significant uncertainty. However general type-2 fuzzy systems are more complex than type-1 fuzzy systems. Support vector machines are similar to fuzzy systems in that they can also model systems that are non-linear in nature. In the proposed model the consequent parameters of type-2 fuzzy rules are learnt using support vector regression and an efficient closed-form type reduction strategy is used to simplify the computations. Support vector regression improved the generalisation performance of the fuzzy rule-based system in which the fuzzy rules were a set of interpretable IF-THEN rules. The performance of the proposed model was demonstrated by conducting case studies for the non-linear system approximation and prediction of chaotic time series. The model yielded promising results and the simulation results are compared to the results published in the area

Peptide-Mediated Constructs of Quantum Dot Nanocomposites for Enzymatic Control of Nonradiative Energy Transfer

Cataloged from PDF version of article.A bottom-up approach for constructing colloidal semiconductor quantum dot (QDot) nanocomposites that facilitate nonradiative Forster-type resonance energy transfer (FRET) using polyelectrolyte peptides was proposed and realized. The electrostatic interaction of these polypeptides with altering chain lengths was probed for thermodynamic, structural, and morphological aspects. The resulting nanocomposite film was successfully cut with the protease by digesting the biomimetic peptide layer upon which the QDot assembly was constructed. The ability to control photoluminescence decay lifetime was demonstrated by proteolytic enzyme activity, opening up new possibilities for biosensor applications

Engineered Peptides for Nanohybrid Assemblies

Cataloged from PDF version of article.Inspired by biological material synthesis, synthetic biomineralization peptides have been screened through a laboratory evolution using biocombinatorial techniques. In this study, using the fine examples in nature, silica binding peptides and gold binding peptides were fused together to form a hybrid peptide. We designed fusion peptides with different gold binding and silica binding parts. First, we have tested the binding capability of the fusion peptides using quartz crystal microbalance on gold surface and silica surface. Second, S1G1 hybrid peptide enabled assembly of gold nanoparticles on a silica surface was achieved. Finally, nanomaterial synthesis ability of the S1G1 peptide was presented by the formation of a silica film on a gold surface. In this study, we are presenting a hybrid peptide tool for nanohybrid assembly as a promising route for nanotechnology applications

Biomedical and biochemical tools of förster resonance energy transfer enabled by colloidal quantum dot nanocrystals for life sciences

Semiconductor quantum nanocrystals (NCs) provide the ability to control and fine-tune peak emission wavelength using the size effect, with a broad optical absorption band (excitation window) increasing toward UV wavelength range. Quantum dots with different peak emission wavelengths can be excited at the same wavelength and offer longer fluorescence lifetimes, which make them desirable donor molecules for Förster resonance energy transfer (FRET)-based applications. In this chapter, the tools of FRET using these quantum dot nanocrystals in life science applications are addressed. © Springer-Verlag Berlin Heidelberg 2013

Effect of vitamin E on the blood-brain barrier permeability in aged rats with ptz-induced convulsions

The effect of vitamin E on the blood-brain barrier (BBB) permeability was studied under conditions of pentylenetetrazole (PTZ)-induced convulsions in aged (23- to 24-month-old) male albino rats; Evans Blue was used as a tracer. The BBB permeability was found to considerably increase in rats with PTZ-evoked seizures; the Evans Blue contents in the left and right hemispheres and cerebellum + brainstem region were significantly higher than those in the control. Vitamin E used in the dose of 70 mg/kg exerted practically no beneficial effect on the increased BBB permeability in rats with seizures, while a greater dose of vitamin E (700 mg/kg) exerted a significant protective effect, especially with respect to the cerebellum + brainstem regions (P < 0.01). The seizure-related rise in the arterial blood pressure was also smaller in the latter experimental group. Thus, our observations confirm the importance of the dose of vitamin E as a protective factor for the BBB permeability and demonstrate that the dose dependence of this antioxidant in aged animals dif fers from that in younger or ganisms.На старих (вік 23–24 місяці) самцях білих щурів досліджували вплив вітаміну Е на розлади проникності гематоенцефалічного бар’єра (ГЕБ), пов’язані з розвитком судомної активності, котра була індукована введенням пентилентетразолу (ПТЗ); як трасер використовували барвник Еванс блакитний. У тварин із ПТЗ-викликаними судомами проникність ГЕБ значно збільшувалася; вміст барвника в тканинах лівої та правої мозкових півкуль, мозочка та стовбура мозку вірогідно перевищував відповідні значення в контролі. Вітамін Е в дозі 70 мг/кг практично не справляв позитивного впливу на збільшену проникність ГЕБ у тварин із судомною активністю. Застосування ж вітаміну Е в більших дозах (700 мг/кг) забезпечувало істотний протективний ефект, особливо щодо зразків тканин мозочка та стовбура мозку (P < 0.01). Підвищення артеріального кров’яного тиску, пов’язане з розвитком судом, в останній з експериментальних серій було помірнішим, ніж у двох інших серіях. Отже, наші спостереження підтверджують важливість дозування вітаміну Е як протективного фактора щодо проникності ГЕБ та вказують на те, що залежність від дози цього вітаміну, використовуваного як антиоксидант, у старих тварин істотно відрізняється від такої у молодших організмів

Spatially Selective Assembly of Quantum Dot Light Emitters in an LED Using Engineered Peptides

Cataloged from PDF version of article.Semiconductor nanocrystal quantum dots are utilized in numerous applications in nano- and biotechnology. In device applications, where several different material components are involved, quantum dots typically need to be assembled at explicit locations for enhanced functionality. Conventional approaches cannot meet these requirements where assembly of nanocrystals is usually material-nonspecific, thereby limiting the control of their spatial distribution. Here we demonstrate directed self-assembly of quantum dot emitters at material-specific locations in a color-conversion LED containing several material components including a metal, a dielectric, and a semiconductor. We achieve a spatially selective immobilization of quantum dot emitters by using the unique material selectivity characteristics provided by the engineered solid-binding peptides as smart linkers. Peptide-decorated quantum dots exhibited several orders of magnitude higher photoluminescence compared to the control groups, thus, potentially opening up novel ways to advance these photonic platforms in applications ranging from chemical to biodetection. © 2011 American Chemical Society