Morphology controlled coating of catalytically active gold structures within flow-focused millifluidic reactor

Synthesis of micro/nanomaterials within confined flow-based systems such as microfluidics has always been a promising research. However, the inability to scale up reagent volumes due to geometric constraints and pressure development within the channels at higher flow rates has limited their usage. In recent times, millifluidics has emerged as a useful technique where, apart from the synthesis, the in situ characterization of materials becomes easier. In this study, formation of morphology-controlled gold structures at different time intervals (viz. 1, 5, and 9 h) within a millifluidic chip reactor was investigated using gold chloride and dimercaptosuccinic acid (DMSA) as precursor reagents and sodium borohydride as the reducing agent. The structures formed were characterized using 3-D X-ray tomography, X-ray absorption near edge spectroscopy (XANES) and scanning electron microscopy (SEM). The X-ray tomography results show that the dimension of the gold structures vary with respect to their time of deposition within the channel. The gold structures formed at 1 h are 26 µm wide, 5 h are 55 µm wide and 9 h are 100 µm wide. However, the height of the gold structures remained relatively uniform and peaked at 27.5 µm for all the samples. The XANES results show that there are differences in the chemical nature and bonding of the structures before and after reduction with sodium borohydride. A linear combination fitting of the XANES spectra show 50% Au and 50% S with both Au-Au and Au-S bonding for the structures before reduction and 83% Au, 17% S predominantly Au-Au bonding after reduction with borohydride. The SEM of the gold structures show hemispherical shape for sample formed for 9 h, flower-shape for 5 h and polygonal-shape for the 1 h sample. The catalytic activity of these gold structures was also demonstrated through 4-nitrophenol and Ferricyanide conversion reactions. In both the conversion reactions, the gold structures formed for 9 h flow time show better catalytic performance in terms of yield with 90.5% conversion for 4-nitrophenol and 85.5% conversion for Ferricyanide

Time-Resolved Investigations of Continuous Flow Synthesis of Nanomaterials and Catalysis Using Millifluidic Reactors for Biomass Conversion Reactors

Millifluidics can be used as a simple tool and convenient platform to perform in-situ investigations on nanoparticles synthesis to generate real-time information in a continuous flow fashion. These investigations can be used to observe the relationship between the structure and performance of nanoparticles for catalytic applications as a function of space and time. These improvements in nanoparticles research offer unique advantages to develop catalysts with molecular strategies. In order to showcase these advantages of the millifluidic reactors, here we: A. Extensively covered a complete literature review on Lab-on-a-chip devices for gold nanoparticle synthesis and as a catalyst support for continuous flow catalysis. This first phase of the work provides detailed information on the synthesis and catalysis applications of nanostructured gold using the lab-on-a-chip systems. The second phase is an experimental investigation, where the millifluidic reactor was used for: B. Continuous flow process for production of water-soluble Platinum-Dimercaptosuccinic acid (Pt(DMSA)) nanoparticles at ambient conditions. The process development was based on in-situ synchrotron radiation-based X-ray absorption spectroscopy (XAS) investigations. The XAS revealed that the nucleation and growth of the Pt(DMSA) nanoparticles was extremely fast. Such a fast nucleation and growth process was also found to hinder coating of the channel walls, except at the zone 1 where the reactants first interact. C. Catalytic oxidation of 5-(Hydroxymethyl)furfural (HMF) to 2,5-Furandicarboxylic acid (FDCA) with nanostructured gold catalyst using millifluidics. The conversion leading from the reactant to primary and secondary products within the millifluidic reactor was analyzed at various spatial intervals to understand the reaction mechanism. The entire process was carried out using an aqueous phase oxidizing agent, tert-Butyl hydroperoxide (TBHP) at ambient temperature and pressure in a continuous flow conditions. The turnover frequency for the catalytic oxidation of HMF using the millifluidic reactor was obtained in the order of 10-26 molecules s-1 in for HMFCA and FDCA after 50 minutes. The results demonstrated in this work highlight significant advantages in carrying out time-resolved continuous flow catalytic reactions using millifluidic reactors

Exploring grassroots innovation phenomenon through the lived experience of an Indian grassroots innovator.

Purpose – The purpose of this paper is to stir the deliberation on understanding grassroots innovation (GI) phenomenon through the lived experience approach and attempt to address the existing void in current literature. Design/methodology/approach – This paper outlines a human science research approach for studying the subjective reality embedded in the GI phenomenon. Such an approach provides a better and more bottom-up understanding of the underlying individual and interpersonal dynamics shaping the GI. Findings – This study provides a richer understanding of the underlying individual and interpersonal dynamics shaping the GI phenomena. This may serve as an aid for future research on scaling, managing GI and developing entrepreneurial capabilities of the grassroots innovators (GIrs). The study also confirms that no single unilateral theory can fully explain the lived experiences of the GIrs at the ideation, opportunity recognition, prototyping and scaling stage of GI. Rather, it is quintessential to have an integrated holistic perspective for understanding GI. This study also highlights the importance of hermeneutic phenomenology in pro-poor innovation research and practice in the near future. Research limitations/implications – This paper’s main limitation is whether the findings can be generalized in a wider context. The authors acknowledge this limitation. However, the purpose of this study is not to generalize the findings but rather provide a contextual understanding of what constitutes the lived experiences of GI. The authors recommend that a future study covering greater number of GIrs across India be undertaken to gain a better appreciation of the bigger picture. Originality/value – Systematic approaches for tapping into GI are conspicuously non-existent and hence a contextual understanding through the proposed holistic lens will assist in thriving of the GI phenomena in South Asian countries such as India

In-orbit Performance of UVIT on ASTROSAT

We present the in-orbit performance and the first results from the ultra-violet Imaging telescope (UVIT) on ASTROSAT. UVIT consists of two identical 38cm coaligned telescopes, one for the FUV channel (130-180nm) and the other for the NUV (200-300nm) and VIS (320-550nm) channels, with a field of view of 28 $arcmin$. The FUV and the NUV detectors are operated in the high gain photon counting mode whereas the VIS detector is operated in the low gain integration mode. The FUV and NUV channels have filters and gratings, whereas the VIS channel has filters. The ASTROSAT was launched on 28th September 2015. The performance verification of UVIT was carried out after the opening of the UVIT doors on 30th November 2015, till the end of March 2016 within the allotted time of 50 days for calibration. All the on-board systems were found to be working satisfactorily. During the PV phase, the UVIT observed several calibration sources to characterise the instrument and a few objects to demonstrate the capability of the UVIT. The resolution of the UVIT was found to be about 1.4 - 1.7 $arcsec$ in the FUV and NUV. The sensitivity in various filters were calibrated using standard stars (white dwarfs), to estimate the zero-point magnitudes as well as the flux conversion factor. The gratings were also calibrated to estimate their resolution as well as effective area. The sensitivity of the filters were found to be reduced up to 15\% with respect to the ground calibrations. The sensitivity variation is monitored on a monthly basis. UVIT is all set to roll out science results with its imaging capability with good resolution and large field of view, capability to sample the UV spectral region using different filters and capability to perform variability studies in the UV.Comment: 10 pages, To appear in SPIE conference proceedings, SPIE conference paper, 201

Functional site prediction selects correct protein models

<p>Abstract</p> <p>Background</p> <p>The prediction of protein structure can be facilitated by the use of constraints based on a knowledge of functional sites. Without this information it is still possible to predict which residues are likely to be part of a functional site and this information can be used to select model structures from a variety of alternatives that would correspond to a functional protein.</p> <p>Results</p> <p>Using a large collection of protein-like decoy models, a score was devised that selected those with predicted functional site residues that formed a cluster. When tested on a variety of small <it>α</it>/<it>β</it>/<it>α </it>type proteins, including enzymes and non-enzymes, those that corresponded to the native fold were ranked highly. This performance held also for a selection of larger <it>α</it>/<it>β</it>/<it>α </it>proteins that played no part in the development of the method.</p> <p>Conclusion</p> <p>The use of predicted site positions provides a useful filter to discriminate native-like protein models from non-native models. The method can be applied to any collection of models and should provide a useful aid to all modelling methods from <it>ab initio </it>to homology based approaches.</p

Enlarging the European Union: Taxation and Corruption in the New Member States

This paper addresses the run up to the recent European Union enlargement. It considers the accession of 10 Eastern European countries in view of the pre-existing economic conditions. The paper also raises the question how the new member states can tackle their deficit problems. In particular, the paper pays attention to the question at what point the emphasis should be placed on cutting expenditure rather than raising revenues. Furthermore, the paper addresses tax capacity and tax effort in the new member states. Finally, the paper looks at possible negative relationships between corruption and tax effort on the one hand and corruption and foreign direct investments on the other

Harmonizing semantic annotations for computational models in biology

Life science researchers use computational models to articulate and test hypotheses about the behavior of biological systems. Semantic annotation is a critical component for enhancing the interoperability and reusability of such models as well as for the integration of the data needed for model parameterization and validation. Encoded as machine-readable links to knowledge resource terms, semantic annotations describe the computational or biological meaning of what models and data represent. These annotations help researchers find and repurpose models, accelerate model composition and enable knowledge integration across model repositories and experimental data stores. However, realizing the potential benefits of semantic annotation requires the development of model annotation standards that adhere to a community-based annotation protocol.Without such standards, tool developers must account for a variety of annotation formats and approaches, a situation that can become prohibitively cumbersome and which can defeat the purpose of linking model elements to controlled knowledge resource terms. Currently, no consensus protocol for semantic annotation exists among the larger biological modeling community. Here, we report on the landscape of current annotation practices among the Computational Modeling in BIology NEtwork community and provide a set of recommendations for building a consensus approach to semantic annotation

Regulatory feedback response mechanisms to phosphate starvation in rice

Phosphorus is a growth-limiting nutrient for plants. The growing scarcity of phosphate stocks threatens global food security. Phosphate-uptake regulation is so complex and incompletely known that attempts to improve phosphorus use efficiency have had extremely limited success. This study improves our understanding of the molecular mechanisms underlying phosphate uptake by investigating the transcriptional dynamics of two regulators: the Ubiquitin ligase PHO2 and the long non-coding RNA IPS1. Temporal measurements of RNA levels have been integrated into mechanistic mathematical models using advanced statistical techniques. Models based solely on current knowledge could not adequately explain the temporal expression profiles. Further modeling and bioinformatics analysis have led to the prediction of three regulatory features: the PHO2 protein mediates the degradation of its own transcriptional activator to maintain constant PHO2 mRNA levels; the binding affinity of the transcriptional activator of PHO2 is impaired by a phosphate-sensitive transcriptional repressor/inhibitor; and the extremely high levels of IPS1 and its rapid disappearance upon Pi re-supply are best explained by Pi-sensitive RNA protection. This work offers both new opportunities for plant phosphate research that will be essential for informing the development of phosphate efficient crop varieties, and a foundation for the development of models integrating phosphate with other stress responses

Bioinformatics research in the Asia Pacific: a 2007 update

We provide a 2007 update on the bioinformatics research in the Asia-Pacific from the Asia Pacific Bioinformatics Network (APBioNet), Asia's oldest bioinformatics organisation set up in 1998. From 2002, APBioNet has organized the first International Conference on Bioinformatics (InCoB) bringing together scientists working in the field of bioinformatics in the region. This year, the InCoB2007 Conference was organized as the 6th annual conference of the Asia-Pacific Bioinformatics Network, on Aug. 27–30, 2007 at Hong Kong, following a series of successful events in Bangkok (Thailand), Penang (Malaysia), Auckland (New Zealand), Busan (South Korea) and New Delhi (India). Besides a scientific meeting at Hong Kong, satellite events organized are a pre-conference training workshop at Hanoi, Vietnam and a post-conference workshop at Nansha, China. This Introduction provides a brief overview of the peer-reviewed manuscripts accepted for publication in this Supplement. We have organized the papers into thematic areas, highlighting the growing contribution of research excellence from this region, to global bioinformatics endeavours