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The design and development of a timer based revolution per minute (RPM) measurement system were described in this paper. The rotating shaft of a dc motor was used to measure the RPM and timer integrated circuit (IC) 555 was used in astable mode. The frequency of timer output waveform measured by a digital storage oscilloscope (DSO) is almost linearly proportional to the RPM of rotating shaft, and the RPM also linearly varies with the change of the external input voltage level. Hence the linear relationship between the frequency of timer output waveform and the RPM can be obtained. The main advantages of this developed system are linear input-output relationship, small size, easy to carry and cost effective. [ABSTRACT FROM AUTHOR]

In this paper, we have presented a simple approach for experimental and application study on LabVIEW based temperature transmitter with NI myRIO device in the laboratory. In this work, to study the small range of temperature (40 -- 100 °C) although different temperature sensors can be used still, we have used here a K-type thermocouple as the measuring temperature sensor. The analog output voltage of thermocouple is amplified by instrumentation amplifier and the amplified signal is fed to the analog input of NI myRIO device which converts the analog input voltage signal as per the algorithm developed with virtual instrumentation based programming and provides the corresponding 4 -- 20 mA output current signal in the analog output terminal of the device. Results show that input-output i. e. temperature-current relationship is linear. This low cost developed transmitter is very simple and it can be recommended for academic, scientific and industrial development of data acquisition systems, control and analysis of instruments. [ABSTRACT FROM AUTHOR]

Defects and traps in strained-Si n-type metal-oxide-semiconductor field effect transistors (MOSFETs) are studied in detail. The inelastic electron tunneling spectroscopy (IETS) technique is shown to be capable of probing traps in ultrathin gate dielectrics and obtain the energies and spatial locations of the traps. Detailed analyses of electrical stress-induced build-up of traps and electrically active bonding defects and identification of the trap-features including trap-assisted conduction and charge-trapping have been performed. The location and energies of the traps are estimated from the IETS spectra measured at both bias polarities. Identification of the acoustic and optical phonon modes (inelastic) as well as trap-features (elastic) helps in better understandings of the complex transport-mechanisms in gate dielectrics on strained layers. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Measurement Science & Instrumentation is the property of Journal of Measurement Science & Instrumentation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In spite of inventing several anticancer agents the clinical payoff still remains unsatisfactory because of their severe host toxicity due to their nonspecific biodistribution in the body. To achieve high efficiency in anti-cancer drug delivery, thus, we designed and developed a single component photoresponsive drug delivery system, a fusion of two platforms spiropyran and coumarin, which synchronizes two controlling factors: first, the lower pH of cancer tissue, which acts as an internal control and leads to the ring opening of spiropyran resulting in a distinct colour change and fluorescence activation of coumarin; and second, the release of the anti-tumor drug by the externally controlled light. Highly fluorescent nature and promising biocompatibility make the SP–Cou–Cbl system suitable for cell imaging and in vitro studies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Measurement Science & Instrumentation is the property of Journal of Measurement Science & Instrumentation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A physically based compact mobility model for organic thin-film transistors (OTFTs) with an analysis of bias-dependent Fermi-energy ( EF ) movement in the bandgap ( Eg ) is presented. Mobility in the localized and extended energy states predicts the drain-current behavior in the weak and strong accumulation operations of OTFTs, respectively. A hopping mobility model as a function of the surface potential is developed to describe the carrier transport through localized energy states located inside Eg . The Poole–Frenkel parallel-field-effect mobility and vertical-field-effect mobility are considered to interpret the bandlike carrier transport in the extended energy states. The parallel field effect on mobility is more pronounced for shorter channel length OTFTs and is considered by developing a channel-length-dependent mobility model. The vertical field effect on mobility is included to account for the effect of mobility on carrier transport at high gate-voltage-induced fields. We also compared the model results with 2-D device simulations and measurements to verify the developed mobility model. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Measurement Science & Instrumentation is the property of Journal of Measurement Science & Instrumentation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A compact surface potential based model for organic thin-film transistors (OTFTs), including both tail and deep trap states across the band gap, is reported. The model has been developed on the basis of a complete surface potential approach for undoped-body OTFTs. Accurate surface potentials are calculated by explicitly including the floating backside potential that varies with applied biases. A pseudo-2D resistor model is developed to capture the structural features of the OTFT. The resistor model considers, in particular, the effects originating from a bias dependent 2D current flow in the channel region and results in accurate reproduction of the electrical characteristics. The fitting capability of the developed OTFT model is verified against measured high-performance dinaphtho thieno thiophene (DNTT) based field-effect transistor data. Accurate reproduction of the current characteristics of the OTFT test structures is verified from a week to a strong inversion regime. [ABSTRACT FROM PUBLISHER]

The article presents a study which evaluates the short term dietary influence of edible mushrooms' purified β-glucan on the innate immunity and disease resistance of broiler chicken. The study uses the neutrophil, macrophage, and lymphocyte functional assay in vitro for the assessment of the treated and control birds at the end of the experiment. Results show that β-glucan has the potential as an immunostimulant in poultry.

Based on ab initio formulation and using nonequilibrium Green's function (NEGF) formalism, electronic transport in the presence of electron-phonon interactions in strained-engineered nanoscale transistors is presented. Ab initio methods are applied to treat the metal/semiconductor interface properly. NEGF formalism is applied as quantum transport and phonon scattering are the dominant factors in devices under realistic operating voltages. Local self-energy functions for electron-phonon scattering have been obtained using deformation potential theory. This approach is applied to the study of electronic transport in strain-engineered nanowire transistors. Electron-phonon interactions on broadening of local density of states are also reported. [ABSTRACT FROM AUTHOR]

We present an automated evaluation procedure to characterize MOS capacitors involving high-k gate dielectrics. Suitability of LabVIEW environment for online web-based semiconductor device characterization is demonstrated. Developed algorithms have been successfully applied to automate the MOS capacitor measurements for Capacitance-Voltage, Conductance-Voltage and Current- Voltage characteristics. Implementation of the algorithm for use as a remote internet-based characterization tool where the client and server communicate with each other via web services is also shown. [ABSTRACT FROM AUTHOR]

Mushroom glucan and bovine lactoferrin (Lf), known for their immunostimulatory potential, were used as adjuvant in conjunction with a formalin-killed Aeromonas hydrophila vaccine in catla, Catla catla. In vitro antigen-specific responsiveness of catla leucocytes and protective responses against experimental challenge with homologous antigen were monitored following immunization. Antigen-specific proliferation, ‘macrophage activating factor’ (MAF) production and antibody production were significantly higher in fish injected with glucan adjuvanted vaccine. Lf adjuvanted preparations showed a weak proliferative response and MAF production, although the antibody production was significantly higher than the controls. A good degree of protection was achieved with the glucan adjuvanted vaccine. However, in spite of producing significant anti- A. hydrophila antibody, Lf adjuvanted vaccine did not confer any protection following challenge with A. hydrophila. The potential of adjuvanticity of mushroom glucan and bovine Lf in intraperitoneal vaccination is discussed. [ABSTRACT FROM AUTHOR]

Agglutinin and toxin was isolated and purified from Abrus precatorius seeds using conventional biochemical techniques such as Sepharose 4B affinity chromatography, Sephadex G-100 gel filtration and analytical HPLC chromatography. The yield of purified agglutinin was 272 mg per 50 g of seeds which was composed of 8.0% agglutinin and 6.1% toxin. SDS gel electrophoresis of purified protein under reducing and non-reducing conditions of native and denatured protein revealed four bands with molecular weights ranging from 31 to 66 kDa by protein and glycoprotein staining procedures. The adjuvant property of abrus agglutinin was evaluated using rat as an animal model, in comparison with Freund's complete adjuvant. Ovalbumin was used as a test antigen and was injected along with Freund's complete adjuvant (Group I experimental animals) and along with denatured abrus protein (Group II experimental animals). The humoral response was compared between two groups of animals (Group I and II) for total (by sandwich ELISA) and specific response (by antibody capture assay). Group II animals which received denatured abrus protein along with test antigen showed a significantly higher IgG response of 23.0 +/- 2.37 mg ml[sup -1] (p < 0.001) when compared to Group I animals (14.0 +/- 2.50 mg ml[sup -1]). However, there was no statistically significant difference between Group I and Group II, with respect to specific IgG response to test antigen. Thus, the present investigation suggests that the denatured abrus agglutinin can be used as an effective alternative protein adjuvant. [ABSTRACT FROM AUTHOR]

Correction for ‘A spiropyran–coumarin platform: an environment sensitive photoresponsive drug delivery system for efficient cancer therapy’ by Shrabani Barman et al., J. Mater. Chem. B, 2017, DOI: 10.1039/c7tb00379j. [ABSTRACT FROM AUTHOR]

The design of nanomedicines from the tuned architecture polymer is a leading object of immense research in recent years. Here, smart thermoresponsive micelles were prepared from novel architecture four-arm star block copolymers, namely, pentaerythritol polycaprolactone-b-poly(N-isopropylacrylamide) and pentaerythritol polycaprolactone-b-poly(N-vinylcaprolactam). The polymers were synthesized and tagged with folic acid (FA) to render them as efficient cancer cell targeting cargos. FA-conjugated block copolymers were self-assembled to a nearly spherical (ranging from 15 to 170 nm) polymeric micelle (FA-PM) with a sufficiently lower range of critical micelle concentration (0.59 × 10(-2) to 1.52 × 10(-2) mg/mL) suitable for performing as an efficient drug carrier. The blocks show lower critical solution temperature (LCST) ranging from 30 to 39 °C with high DOX-loading content (24.3%, w/w) as compared to that reported for a linear polymer in the contemporary literature. The temperature-induced reduction in size (57%) of the FA-PM enables a high rate of DOX release (78.57% after 24 h) at a temperature above LCST. The DOX release rate has also been tuned by on-demand administration of temperature. The in vitro biocompatibilities of the blank and DOX-loaded FA-PMs have been studied by the MTT assay. The cellular uptake study proves selective internalization of the FA-PM into cancerous cells (C6 glioma) compared that into normal cells (HaCaT). In vivo administration of the DOX-loaded FA-PMs into the C6 glioma rat tumor model resulted in significant accumulation in tumor sites, which drastically inhibited the tumor volume by ∼83.9% with respect to control without any significant systemic toxicity.

Polysaccharides such as glucans are the best known and most potent mushroom-derived substances with antitumor and immunomodulating properties. However, a vast variety of mushroom species remain unexplored. The present study aims at exploring the possible role of a heteroglucan designated as AE2, isolated from Astraeus hygrometricus, on tumor bearing host. AE2 mediated tumor regression through the reversal of tumor induced immunosupression. Tumor-associated macrophages from AE2 administered tumor bearing host have been demonstrated to possess augmented surface expression of co-stimulatory molecules and MHC-II, representing essentially elevated state of macrophage activation. NK cell activity has also been found to be elevated with the AE2 treatment while the Th1 cytokine in the tumor micro-environment increases with the treatment, the Th2 cytokine levels concomitantly decreases. Further, following the immunoactivation, Daltons lymphoma (DL) cells has undergone apoptosis, thereby resulting in reduction of tumor growth and increased survival rate of the tumor bearing host. The present study sheds light on the potent antitumor property of the heteroglucan AE2 isolated from A. hygrometricus, and can be extended further to develop therapeutic protocols for treatment of cancer or disease resulting in immunosuppression., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

The present study describes a systematic approach towards the design and development of novel, bio-functionalized, magneto-fluorescent nanoparticles for cancer-specific targeting. Biocompatible, hydrophilic, magneto-fluorescent nanoparticles with surface-pendant amine, carboxyl or aldehyde groups, to be later used for bio-conjugation, were designed using an aminophosphonic acid coupling agent. These magneto-fluorescent nanoparticles were further functionalized with folic acid, using diverse conjugation strategies. A series of new iron-oxide folate nanoconjugates with excellent aqueous dispersion stability and reasonably good hydrodynamic sizes under a wide range of physiological conditions were developed. These ultradispersed nanosystems were analyzed for their physicochemical properties and cancer-cell targeting ability, facilitated by surface modification with folic acid. The nanoparticle size, charge, surface chemistry, magnetic properties and colloidal stability were extensively studied using a variety of complementary techniques. Confocal microscopy, performed with folate receptor positive human cervical HeLa cancer cells, established that these non-cytotoxic iron-oxide folate nanoconjugates were effectively internalized by the target cells through receptor-mediated endocytosis. Cell-uptake behaviors of nanoparticles, studied using magnetically activated cell sorting (MACS), clearly demonstrated that cells over-expressing the human folate receptor internalized a higher level of these nanoparticle-folate conjugates than negative control cells.

Mycobacterium leprae heat-shock proteins hsp65 and hsp18 have received immense attention as major T-cell target antigens in leprosy. Both of these hsps and their tryptic fragments were characterized for their ability to stimulate CD4+ T cells derived from polar leprosy cases and healthy contacts. The optimal digestion of hsps with trypsin yielded four fragments of hsp65--TDB65-1 (24 kDa), TDB65-2 (18 kDa), TDB65-3 (17 kDa), TDB65-4 (14 kDa)-- and three of hsp18--TDB18-1 (10 kDa), TDB18-2 (5 kDa), TDB18-3 (3 kDa). While all of these tryptic fragments and undigested hsps triggered CD4+ T cells from tuberculoid (TT) leprosy patients and healthy contacts (SI > 2), only two fragments--TDB65-2 and TDB18-3--were found to be stimulatory in anergic lepromatous (LL) leprosy patients (SI = 5.27 and 3.0, respectively). Blocking studies using allele-specific anti-DR monoclonal antibodies revealed multiple HLA-Dr restriction, with DR2 providing the strongest restriction in both TT as well as LL leprosy. These findings indicate that M. leprae hsps and their trypsin-digested fragments are promiscuous and recognizable in the context of diverse HLA alleles, of which DR2 is the most efficient restriction element. The 18-kDa fragment of hsp65 and the 3-kDa fragment of hsp18 are the most versatile fragments that could elicit in vitro proliferation in both polar forms of leprosy.

Microbial production of L-tyrosine by direct fermentation and by enzymatic methods has been reviewed. Achievements in this regard made through recombinant DNA techniques have also been included. The review also includes biosynthesis and regulation of tyrosine.

Polyporus ostreiformis produced Mn peroxidase, acid protease, alpha-amylase, and lignin peroxidase, with maximum activities of 40, 8,300, and 4,200 U liter-1 and 50 nkat liter-1, respectively, in nitrogen-limited liquid media. The fungus removed only 18.6% lignin from rice straw in 3 weeks but effected 99% decolorization of Congo red dye in 9 days.

Three toxins, abrin-I, -II, and -III, and two agglutinins, APA-I and -II, were purified from the seeds of Abrus precatorius by lactamyl-Sepharose affinity chromatography followed by gel filtration and DEAE-Sephacel column chromatography. Abrin-I did not bind on DEAE-Sephacel column chromatography and the bound abrin-II, abrin-III, APA-I, and APA-II were eluted with a sodium acetate gradient. The identity of each protein was established by sodium dodecylsulfate-polyacrylamide gel electrophoresis and isoelectric focusing. The relative molecular weights are abrin-I, 64,000; abrin-II and abrin-III, 63,000 each: APA-I, 130,000; and APA-II, 128,000. Isoelectric focusing revealed microheterogeneity due to the presence of isoforms in each protein. Toxicity and binding studies further confirmed the differences among the lectins. The time course of inhibition of protein synthesis in thymocytes by the toxins showed lag times of 78, 61, and 72 min with Ki's of 0.55, 0.99, and 0.74 ms-1 at a 0.63 nM concentration of each of abrin-I, -II, and -III, respectively. A Scatchard plot obtained from the equilibrium measurement for the lectins binding to lactamyl-Sepharose beads showed nonlinearity, indicating a cooperative mode of binding which was not observed for APA-I binding to Sepharose 4B beads. Further, by the criterion of the isoelectric focusing profile, it was shown that the least toxic abrin-I and the highly toxic abrin-II isolated by lactamyl-Sepharose chromatography were not retained on a low-affinity Sepharose 4B matrix, which signifies the necessity of using a high-affinity matrix for the purification of the lectins.

Microbial production of L-tryptophan has been reviewed with 172 references. The review includes different tryptophan producing microorganisms, their optimal cultural conditions, yields, assay and process of recovery. It also includes a discussion on the pathway of tryptophan biosynthesis and its regulation. Achievements in this regard made through genetic engineering have also been included.

Microbial production of L-phenylalanine by direct fermentation and by substrate conversion has been reviewed. The review also includes a discussion on different other methods for phenylalanine production, their advantages and disadvantages with mutants and genetically tailored strains. Biosynthesis of phenylalanine, its regulation in hyperproducing strains and recovery of phenylalanine has been discussed in brief.