Photonic crystal nanofiber using an external grating

We implement a photonic crystal nanofiber device by reversibly combining an optical nanofiber and a nanofabricated grating. Using the finite-difference time-domain method, we design the system for minimal optical loss while tailoring the resonant wavelength and bandwidth of the device. Experimentally we demonstrate that the combined system shows a strong photonic stop-band in good agreement with numerical predictions. The resulting device may be used to realize strong light-matter coupling near to the nanofiber surface

Efficient channeling of fluorescence photons from single quantum dots into guided modes of optical nanofiber

We experimentally demonstrate the efficient channeling of fluorescence photons from single q-dots on optical nanofiber into the guided modes, by measuring the photon-count rates through the guided and radiation modes simultaneously. We obtain the maximum channeling efficiency to be 22.0 (\pm4.8)% at fiber diameter of 350 nm for the emission wavelength of 780 nm. The results may open new possibilities in quantum information technologies for generating single photons into single-mode optical-fibers.Comment: 5 pages, 4 figure

Assessment of antibacterial efficacy of the methanolic extract of Bacillus vietnamensis PBChS1 isolated from marine sediments of Chidiyatapu coast, South Andaman

1009-1017Marine bacteria are of extensive significance as new ‘budding springs’ of a vast number of organic active artefacts. Till now, only a fraction of microorganisms have been scrutinized for bioactive metabolites, yet a colossal sum of these metabolites with unique structural drafts remains untouched and unexploited. In this respect, the species of Bacillus vietnamensis was isolated from the marine sediments of Chidiyatapu coast, South Andaman and characterized by both phenotypic and genotypic methods. The anti-oxidative activities of the methanolic extract were determined by the estimation of TPC (Total Phenolic Content), reducing power, free radical scavenging assay and ferric thiocyanate method. Antibacterial activity of the methanolic extract was analyzed by an agar well diffusion assay confirming the presence of active metabolites of various functional groups by FT-IR, thereby warranting a ‘combinatorial approach’ for applicative pharmacological settings

Assessment of antibacterial efficacy of the methanolic extract of Bacillus vietnamensis PBChS1 isolated from marine sediments of Chidiyatapu coast, South Andaman

Marine bacteria are of extensive significance as new ‘budding springs’ of a vast number of organic active artefacts. Till now, only a fraction of microorganisms have been scrutinized for bioactive metabolites, yet a colossal sum of these metabolites with unique structural drafts remains untouched and unexploited. In this respect, the species of Bacillus vietnamensis was isolated from the marine sediments of Chidiyatapu coast, South Andaman and characterized by both phenotypic and genotypic methods. The anti-oxidative activities of the methanolic extract were determined by the estimation of TPC (Total Phenolic Content), reducing power, free radical scavenging assay and ferric thiocyanate method. Antibacterial activity of the methanolic extract was analyzed by an agar well diffusion assay confirming the presence of active metabolites of various functional groups by FT-IR, thereby warranting a ‘combinatorial approach’ for applicative pharmacological settings

Fluorescence photon measurements from single quantum dots on an optical nanofiber

We experimentally investigate the fluorescence photon emission characteristics for single q-dots by using optical nanofibers. We demonstrate that single q-dots can be deposited along an optical nanofiber systematically and reproducibly with a precision of 5 {\mu}m. For single q-dots on an optical nanofiber, we measure the fluorescence photon numbers coupled into the nanofiber and the normalized photon correlations, by varying the excitation laser intensity. We estimate the fluorescence photon coupling efficiency into the nanofiber guided modes to be higher than 9.4\pm3%.Comment: 9 pages, 7 figures, 1 tabl

Chemical informatics uncovers a new role for moexipril as a novel inhibitor of cAMP phosphodiesterase-4 (PDE4)

PDE4 is one of eleven known cyclic nucleotide phosphodiesterase families and plays a pivotal role in mediating hydrolytic degradation of the important cyclic nucleotide second messenger, cyclic 3′5′ adenosine monophosphate (cAMP). PDE4 inhibitors are known to have anti-inflammatory properties, but their use in the clinic has been hampered by mechanism-associated side effects that limit maximally tolerated doses. In an attempt to initiate the development of better-tolerated PDE4 inhibitors we have surveyed existing approved drugs for PDE4-inhibitory activity. With this objective, we utilised a high-throughput computational approach that identified moexipril, a well tolerated and safe angiotensin-converting enzyme (ACE) inhibitor, as a PDE4 inhibitor. Experimentally we showed that moexipril and two structurally related analogues acted in the micro molar range to inhibit PDE4 activity. Employing a FRET-based biosensor constructed from the nucleotide binding domain of the type 1 exchange protein activated by cAMP, EPAC1, we demonstrated that moexipril markedly potentiated the ability of forskolin to increase intracellular cAMP levels. Finally, we demonstrated that the PDE4 inhibitory effect of moexipril is functionally able to induce phosphorylation of the Hsp20 by cAMP dependent protein kinase A. Our data suggest that moexipril is a bona fide PDE4 inhibitor that may provide the starting point for development of novel PDE4 inhibitors with an improved therapeutic window

Role of voiding and storage symptoms for the quality of life before and after treatment in men with voiding dysfunction

Previous studies on associations between voiding dysfunction and quality of life (QoL) have largely been limited to baseline data. Therefore, we have explored associations between Q (max) and voiding and storage sub-scores of the International Prostate Symptom Score (IPSS) before and after treatment with QoL. Analysis of a single-center database of 2,316 men with voiding dysfunction attributed to benign prostatic hyperplasia undergoing various medical and surgical treatment forms. Q (max) exhibited little correlation with QoL before or after treatment. IPSS inversely correlated with QoL at baseline and after treatment, and IPSS improvements correlated with those of QoL. The associations applied to both the voiding and storage sub-score of the IPSS, with the latter consistently exhibiting somewhat tighter associations. Our post-treatment data support the idea of a cause-effect relationship between voiding symptoms and QoL irrespective of treatment form. While both voiding and storage symptoms contribute to this relationship, storage symptoms play a somewhat greater rol

Active Comb Filter Using Operational Transconductance Amplifier

A new approach for the design of an active comb filter is proposed to remove the selected frequencies of various signals. The proposed filter is based on only OTAs and capacitors, hence suitable for monolithic integrated circuit implementation. The workability of the circuit is tested using PSPICE for test signals of 60, 180, 300, and 420 Hz as in ECG signal. The results are given in the paper and found to agree well with theory