58 research outputs found

    A Conceptual Model of the Incubation of New Technology-Based Ventures: a Social Capital Perspective

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    Technology incubators are newer organizational forms that are created to support and accelerate the development and success of affiliated ventures, particularly new technology-based ventures. Current literature regarding incubators has suggested that an understanding of the incubation process is important when seeking to understand how affiliated ventures develop and grow. However, very little is known about the incubation process, particularly the incubation of technology-based ventures. Prior literature suggests that technology-based ventures develop in terms of both business and technological development and that the incubation process varies along these dimensions. Thus, understanding the incubation of technology–based ventures must consider the differing but simultaneous dynamics of business and technological development. Drawing from the social capital, entrepreneurship, incubation, and organizational learning literature, a conceptual model of the incubation of new technology-based ventures within technology incubators is presented.incubators; new technology-based ventures; entrepreneurship; innovation.

    Innovation and Productivity in U.S. Industry

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    macroeconomics, U.S. industry, productivity, manufacturing, textiles, chemicals

    Defence and space expenditures in the US: An inter-firm analysis

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    The economic impact of defence and space expenditures has been an important policy issue because of the secondary benefits expected to be accruing from it. Although defence and space activities can stimulate the early development of many technologies, the lasting economic impact of these technologies is difficult to measure. To capture the scientific and technological values added of defence and space financed productions, we have depended on the patents and scientific and technical publications as the indicators. The economic performance has been measured by two separate indicators: (a) firm growth in terms of average annual rate of change in the number of employees, and (b) rate of return on sales measured by the company's net profits in relation to sales. From 1970-75 and 1980-85 the weight within the manufacturing sector of both defence contractors and the civilian companies increased. Defence firms gained considerably in terms of sales, employment, gross plants and company funded R&D in the latter period under the Reagan Administration. Whereas this may be considered a Reagan effect in defence procurement, other indicators point to in the opposite direction: (a) decrease in the shares of defence R&D contracts, (b) relatively low growth of patent output as percent of total manufacturing from the defence firms, and (c) decrease in scientific publications from defence firms per 1000 employees. Firm level analysis showed that military R&D contracts did not contribute to economic or technical efficiency. Space expenditure did not contribute to improvement of economic performance as measured by company growth and profitability. NASA contracts were not associated with technical progress measured by patents, but they improved scientific publications. Defence expenditures are not of importance for the overall economic efficiency. The standard financial variables, capital formation and own R&D activities prove mostly relevant. The study is restricted to an efficiency analysis in a cross sectional comparison and does not include the effect of market structure.

    A unique influenza A (H5N1) virus causing a focal poultry outbreak in 2007 in Manipur, India

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    <p>Abstract</p> <p>Background</p> <p>A focal H5N1 outbreak in poultry was reported from Manipur, a north-eastern state, of India, in 2007. The aim of this study was to genetically characterize the Manipur isolate to understand the relationship with other H5N1 isolates and to trace the possible source of introduction of the virus into the country.</p> <p>Results</p> <p>Characterization of the complete genome revealed that the virus belonged to clade 2.2. It was distinctly different from viruses of the three EMA sublineages of clade 2.2 but related to isolates from wild migratory waterfowl from Russia, China and Mongolia. The HA gene, had the cleavage site GERRRRKR, earlier reported in whooper swan isolates from Mongolia in 2005. A stop codon at position 29 in the PB1-F2 protein could have implications on the replication efficiency. The acquisition of polymorphisms as seen in recent isolates of 2005–07 from distinct geographical regions suggests the possibility of transportation of H5N1 viruses through migratory birds.</p> <p>Conclusion</p> <p>Considering that all eight genes of the earlier Indian isolates belonged to the EMA3 sublineage and similar strains have not been reported from neighbouring countries of the subcontinent, it appears that the virus may have been introduced independently.</p

    Theory of nonlinear optical properties of phenyl-substituted polyacetylenes

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    In this paper we present a theoretical study of the third-order nonlinear optical properties of poly(diphenyl)polyacetylene (PDPA) pertaining to the third-harmonic-generation (THG) process. We study the aforesaid process in PDPA's using both the independent electron Hueckel model, as well as correlated-electron Pariser-Parr-Pople (P-P-P) model. The P-P-P model based calculations were performed using various configuration interaction (CI) methods such as the the multi-reference-singles-doubles CI (MRSDCI), and the quadruples-CI (QCI) methods, and the both longitudinal and the transverse components of third-order susceptibilities were computed. The Hueckel model calculations were performed on oligo-PDPA's containing up to fifty repeat units, while correlated calculations were performed for oligomers containing up to ten unit cells. At all levels of theory, the material exhibits highly anisotropic nonlinear optical response, in keeping with its structural anisotropy. We argue that the aforesaid anisotropy can be divided over two natural energy scales: (a) the low-energy response is predominantly longitudinal and is qualitatively similar to that of polyenes, while (b) the high-energy response is mainly transverse, and is qualitatively similar to that of trans-stilbene.Comment: 13 pages, 7 figures (included), to appear in Physical Review B (April 15, 2004

    An avian influenza A(H11N1) virus from a wild aquatic bird revealing a unique Eurasian-American genetic reassortment

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    Influenza surveillance in different wild bird populations is critical for understanding the persistence, transmission and evolution of these viruses. Avian influenza (AI) surveillance was undertaken in wild migratory and resident birds during the period 2007–2008, in view of the outbreaks of highly pathogenic AI (HPAI) H5N1 in poultry in India since 2006. In this study, we present the whole genome sequence data along with the genetic and virological characterization of an Influenza A(H11N1) virus isolated from wild aquatic bird for the first time from India. The virus was low pathogenicity and phylogenetic analysis revealed that it was distinct from reported H11N1 viruses. The hemagglutinin (HA) gene showed maximum similarity with A/semipalmatedsandpiper/Delaware/2109/2000 (H11N6) and A/shorebird/Delaware/236/2003(H11N9) while the neuraminidase (NA) gene showed maximum similarity with A/duck/Mongolia/540/2001(H1N1). The virus thus possessed an HA gene of the American lineage. The NA and other six genes were of the Eurasian lineage and showed closer relatedness to non-H11 viruses. Such a genetic reassortment is unique and interesting, though the pathways leading to its emergence and its future persistence in the avian reservoir is yet to be fully established

    ABC Transporter Genes Show Upregulated Expression in Drug Resistant Clinical Isolates of Candida auris : a Genome-Wide Characterization of ATP-Binding Cassette (ABC) Transporter Genes

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    Funding This work was supported by the ICMR (AMR/149/2018-ECD-II) and DBT (BT/PR14117/BRB/10/1420/2015) to RP. AKM appreciates the support by research grant EMR/2016/001927 and DST PURSE II from the Department of Science and Technology (IN). MW was grateful for a Senior Research Fellowship from the University Grant Commission. NG acknowledges the Wellcome Trust support of a Senior Investigator (101873/Z/13/Z), Collaborative (200208/A/15/Z), and Strategic Awards (097377/Z11/Z), and the MRC Centre for Medical Mycology (MR/N006364/1). AJM was supported by the University of Aberdeen studentship. Work in AL’s laboratory was supported by the Wellcome Trust (212524/Z/18/Z) and the Medical Research Council (MRC) Centre for Medical Mycology at the University of Aberdeen (MR/P501955/1 and MR/N006364/1). Acknowledgments We thank the Centre for Genome Enabled Biology and Medicine at the University of Aberdeen (E. Collie-Duguid and S. Shaw) for sequencing and support with genome analysis.Peer reviewedPublisher PD

    Theory of excited state absorptions in phenylene-based π\pi-conjugated polymers

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    Within a rigid-band correlated electron model for oligomers of poly-(paraphenylene) (PPP) and poly-(paraphenylenevinylene) (PPV), we show that there exist two fundamentally different classes of two-photon Ag_g states in these systems to which photoinduced absorption (PA) can occur. At relatively lower energies there occur Ag_g states which are superpositions of one electron - one hole (1e--1h) and two electron -- two hole (2e--2h) excitations, that are both comprised of the highest delocalized valence band and the lowest delocalized conduction band states only. The dominant PA is to one specific member of this class of states (the mAg_g). In addition to the above class of Ag_g states, PA can also occur to a higher energy kAg_g state whose 2e--2h component is {\em different} and has significant contributions from excitations involving both delocalized and localized bands. Our calculated scaled energies of the mAg_g and the kAg_g agree reasonably well to the experimentally observed low and high energy PAs in PPV. The calculated relative intensities of the two PAs are also in qualitative agreement with experiment. In the case of ladder-type PPP and its oligomers, we predict from our theoretical work a new intense PA at an energy considerably lower than the region where PA have been observed currently. Based on earlier work that showed that efficient charge--carrier generation occurs upon excitation to odd--parity states that involve both delocalized and localized bands, we speculate that it is the characteristic electronic nature of the kAg_g that leads to charge generation subsequent to excitation to this state, as found experimentally.Comment: Revtex4 style, 2 figures inserted in the text, three tables, 10 page

    Characterization of the Influenza A H5N1 Viruses of the 2008-09 Outbreaks in India Reveals a Third Introduction and Possible Endemicity

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    Widespread infection of highly pathogenic avian influenza A H5N1 was reported from backyard and commercial poultry in West Bengal (WB), an eastern state of India in early 2008. Infection gradually spread to Tripura, Assam and Sikkim, the northeastern states, with 70 outbreaks reported between January 2008 and May 2009. Whole genome sequence analysis of three isolates from WB, one isolate from Tripura along with the analysis of hemagglutinin (HA) and neuraminidase (NA) genes of 17 other isolates was performed during this study. In the HA gene phylogenetic tree, all the 2008-09 Indian isolates belonged to EMA3 sublineage of clade 2.2. The closest phylogenetic relationship was found to be with the 2007-09 isolates from Bangladesh and not with the earlier 2006 and 2007 Indian isolates implying a third introduction into the country. The receptor-binding pocket of HA1 of two isolates from WB showed S221P mutation, one of the markers predicted to be associated with human receptor specificity. Two substitutions E119A (2 isolates of WB) and N294S (2 other isolates of WB) known to confer resistance to NA inhibitors were observed in the active site of neuraminidase. Several additional mutations were observed within the 2008-09 Indian isolates indicating genetic diversification. Overall, the study is indicative of a possible endemicity in the eastern and northeastern parts of the country, demanding active surveillance specifically in view of the critical mutations that have been observed in the influenza A H5N1 viruses
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