When Micro Shapes the Meso: Learning Networks in a Chilean Wine Cluster

Most analyses of the relationship between spatial clustering and the technological learning of firms have emphasised the influence of the former on the latter, and have focused on intra-cluster learning as the driver of innovative performance. This paper reverses those perspectives. It examines the influence of individual firms' absorptive capacities on both the functioning of the intra-cluster knowledge system and its interconnection with extra-cluster knowledge. It applies social network analysis to identify different cognitive roles played by cluster firms and the overall structure of the knowledge system of a wine cluster in Chile. The results show that knowledge is not diffused evenly 'in the air', but flows within a core group of firms characterised by advanced absorptive capacities. Firms' different cognitive roles include some - as in the case of technological gatekeepers - that contribute actively to the acquisition, creation and diffusion of knowledge. Others remain cognitively isolated from the cluster, though in some cases strongly linked to extra-cluster knowledge. Possible implications for policy are noted.clusters, absorptive capacity, knowledge communities, technological gatekeepers

Analisis Pengaruh Harga Diskon dan Kemasan terhadap Keputusan Pembelian Konsumen pada Produk Minyak Goreng dalam Kemasan

Penelitian ini bertujuan untuk menguji pengaruh harga diskon dan kemasan terhadap keputusan pembelian konsumen pada produk minyak goreng dalam kemasan. Penelitian ini menggunakan data primer yang berasal dari 212 yang berada pada kawasan Rasuna Epicentrum. Data dikumpulkan melalui penyebaran kuesioner dengan menggunakan teknik purposive sampling. Hasil penelitian dengan analisis regresi linear sederhana menunjukkan bahwa variabel harga diskon dan kemasan memiliki pengaruh positif dan signifikan terhadap keputusan pembelian konsumen produk minyak goreng dalam kemasan. Berdasarkan analisis korelasi, variabel kemasan merupakan variabel yang memiliki hubungan lebih kuat terhadap keputusan pembelian kosumen produk minyak goreng kemasan dibandingkan dengan variabel harga diskon. Berdasarkan uji secara simultan, variabel harga diskon dan kemasan memiliki pengaruh yang simultan dan positif terhadap keputusan pembelian konsumen minyak goreng dalam kemasan. Uji korelasi antara variabel harga diskon dan kemasan terhadap keputusan pembelian menunjukkan hubungan pada tingkatan sedang

Expression and refolding of the protective antigen of Bacillus anthracis: A model for high-throughput screening of antigenic recombinant protein refolding

Bacillus anthracis protective antigen (PA) is a well known and relevant immunogenicprotein that is the basis for both anthrax vaccines and diagnostic methods. Properly foldedantigenic PA is necessary for these applications. In this study a high level of PA was obtained inrecombinant Escherichia coli. The protein was initially accumulated in inclusion bodies, whichfacilitated its efficient purification by simple washing steps; however, it could not be recognizedby specific antibodies. Refolding conditions were subsequently analyzed in a high-throughputmanner that enabled nearly a hundred different conditions to be tested simultaneously. Therecovery of the ability of PA to be recognized by antibodies was screened by dot blot usinga coefficient that provided a measure of properly refolded protein levels with a high degreeof discrimination. The best refolding conditions resulted in a tenfold increase in the intensityof the dot blot compared to the control. The only refolding additive that consistently yieldedgood results was L-arginine. The statistical analysis identified both cooperative and negativeinteractions between the different refolding additives. The high-throughput approach describedin this study that enabled overproduction, purification and refolding of PA in a simple andstraightforward manner, can be potentially useful for the rapid screening of adequate refoldingconditions for other overexpressed antigenic proteins.Fil: Pavan, María Elisa. Biochemiq; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; ArgentinaFil: Pavan, Esteban E.. Politecnico di Milano; ItaliaFil: Cairo, Fabian Martin. Biochemiq; ArgentinaFil: Pettinari, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales; Argentin

Cosmic Microwave Background temperature and polarization anisotropies from the large-N limit of global defects

We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N)-theories. We point out a problem in the standard approach of treating the radiation-matter transition by interpolating the eigenvectors of the unequal-time correlators of the source energy-momentum tensor. This affects the CMB predictions from all type of cosmic defects. We propose a method to overcome this difficulty, and find that in the large-N global model that we study, differences in the final CMB power spectra amplitudes reach up to 25%, when compared to implementations of the eigenvector interpolation technique. We discuss as well how to optimally search for the contribution in the CMB from active sources such as cosmic defects, in experiments like Planck, COrE and PRISM.Comment: 16+4 pages, 13 figures (Version 2: minor changes to match published version in PRD

The local B-polarization of the CMB: a very sensitive probe of cosmic defects

We present a new and especially powerful signature of cosmic strings and other topological or non-topological defects in the polarization of the cosmic microwave background (CMB). We show that even if defects contribute 1% or less in the CMB temperature anisotropy spectrum, their signature in the local $\tilde{B}$-polarization correlation function at angular scales of tens of arc minutes is much larger than that due to gravitational waves from inflation, even if the latter contribute with a ratio as big as $r\simeq 0.1$ to the temperature anisotropies. We show that when going from non-local to local $\tilde{B}$-polarization, the ratio of the defect signal-to-noise with respect to the inflationary value increases by about an order of magnitude. Proposed B-polarization experiments, with a good sensitivity on arcminute scales, may either detect a contribution from topological defects produced after inflation or place stringent limits on them. Even Planck should be able to improve present constraints on defect models by at least an order of magnitude, to the level of \ep <10^{-7}. A future full-sky experiment like CMBpol, with polarization sensitivities of the order of $1\mu$K-arcmin, will be able to constrain the defect parameter \ep=Gv^2 to a few $\times10^{-9}$, depending on the defect model.Comment: Version Published in Physics Letters

Trends in the Global Distribution of R&D since the 1970s: Data, their Interpretation and Limitations

The 1970 ‘Sussex Manifesto’ was one of the earliest global policy reports to use statistical data about R&D that were starting to become available on an internationally comparable basis, though only in a very sketchy form for developing countries. It demonstrated the marginal position of that group of countries as contributors to the world’s R&D, accounting for only about 2 per cent of the global total. It also couched some of its core recommendations about policy in terms of quantitative indicators of R&D, but highlighted several major limitations of such indicators as tools for policy. This Background Paper revisits the global data to review how the distribution of R&D between groups of countries has changed since the 1960s, in particular with respect to the marginal position of developing countries. It reveals mixed trends. The economies that were ‘developing’ in the 1960s now account for a much larger share of the global total, but this is concentrated in a small number of countries that are highly R&D-intensive and/or very large like India and China, leaving many others still playing only a marginal role. The paper also returns to some of the Manifesto’s concerns about the limitations of R&D indicators as a basis for policy debate. It notes a surprising persistence of many of those earlier limitations.ESR