224 research outputs found
The importance of Intermediaries organizations in international R&D cooperation: an empirical multivariate study across Europe
Despite the large number of publications related to business cooperation in R&D and the wide perception of the importance of intermediary institutions in the R&D cooperation process, empirical studies on its role are scarce, scattered and fragmented. Moreover, the academic work developed in this area is basically of a theoretical nature, whereas the international perspective of R&D cooperation is seldom approached. Departing from a unique database that includes 473 R&D cooperation projects developed within the 6th Framework Programme, involving firms and intermediaries from all European Union countries, this paper gauges the determinants of the importance attached to Intermediaries, through a direct survey to the organizations involved. Based on an estimation of the multivariate model, this study demonstrates that the importance given to Intermediaries depends more on project features than on the characteristics of the participating organizations. In particular, the nationality of participating organizations and the promoter emerged with a strong explanatory power: ceteris paribus, projects with at least one participant from the United Kingdom tend to assign greater importance to intermediaries in international R&D cooperation. Unambiguously, results evidence that the innovating capacity of an organization emerges (both positively and significantly) associated with a greater importance attached to Intermediaries.R&D Cooperation; Intermediaries; International projects; Europe
The deflocculation of kaolin suspensions : the effect of various electrolytes
The deflocculation effect of conventional additives to kaolin suspensions is evaluated from the
results standard rheological measurements. Several widely used electrolytes (NaOH, Na2C03,
Na2Si03, SHMP = sodium hexametaphosphate, and CMC = sodium salts of carboxymethylcellulose)
have been tested. The optimal concentrations of these deffloculants, in respect to
reaching the maximum reduction of initial suspension viscosity, are found. The stability of
deflocculated kaolin suspensions against sedimentation is evaluated and different aspects of the
observed flow enhancement discussed. Inorganic electrolytes are found to be more effective in
viscosity reduction, but on the other hand, low-molecular organic CMC additives produce more
stable final suspensions.Czech Science Foundation GACR through the contract P101/12/058
Mathematical modeling of the thermal degradation kinetics of vitamin C in cupuaçu (Theobroma grandiflorum) nectar
The thermal degradation kinetics of both components of vitamin C, ascorbic acid (AA) and dehydroascorbic acid (DHAA), were
determined in a nectar of Cupuacßu (Theobroma grandi¯orum) with 25% of pulp and 15% of sugar in water. AA was assayed by
HPLC and the results showed that AA degraded into DHAA. A reversible ®rst order model described well the AA degradation data,
with an activation energy of 74 5 kJ/mol and k80 C 0:032 0:003min
ÿ1. DHAA kinetic behavior suggested a consecutive ®rst
order reaction where DHAA was the intermediate product of AA degradation. A mechanistic model was derived to predict DHAA
concentration. Rate constants were replaced by the Arrhenius equation in the model to evaluate the temperature dependence and the
kinetic parameters for AA degradation, previously determined, were used. An activation energy of 65 9 kJ/mol and a k80 C of
0:013 0:003 min
ÿ1 were estimated. The present ®ndings will help to predict the best Cupuacßu nectar processing conditions that
minimize degradation of an important quality factor such as vitamin C
Detection of adulterations in food products containing milk and/or milk proteins
A critical review of the most relevant analytical methodologies for quality and authenticity control of dairy products and foods containing milk proteins is presented. Chromatographic, electrophoretic and immunological methods are used for: detection of cow's milk in ewe and goat milks, detection of whey added to milk, detection of caseins and/or whey proteins in non-lactic foods and study compounds resulting from milk proteins degradation. Techniques based on polimerase chain reaction are also suitable for detection of cow's milk on cheeses of ewe and goat milks
Influence of culture medium and temperature in the growth and sporulation of Penicillium expansum
Selection of materials with potential for immobilization of the fungus Penicillium expansum during the sucrose fermentation
Fructooligosaccharide production by Penicillium expansum
Fructooligosaccharides (FOS) production
by Penicillium expansum was evaluated. In a first
stage, the best conditions for P. expansum growth and
sporulation were established with potato/dextrose/
agar being the most suitable medium at between 22
and 25°C, giving good growth and good sporulation.
The inocula from this medium were used for FOS
production using shake-flask cultures, and yielded
0.58 g FOS/g sucrose (3.25 g FOS/l.h), demonstrating
the potential of this strain for sucrose conversion
to FOS.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BPD/38212/200
Response surface optimization of the culture medium for production of elastin-like polymers by E. coli
ASTM program POCI 2010 (project POCI/CTM/57177/2004) suported by FEDER and
FCTElastin-Like Polymers (ELP`s), a family of proteins based on repetitive pentapeptide sequences known by their smart and extremely biocompatible behavior (1, 2), are of great interest to our research group. Ongoing work using E. coli as the expression system, strongly suggests that the biomass and polymer production are closely related.
The Response Surface Methodology (RSM) is a collection of mathematical and statistical techniques useful for the modeling and analysis of problems, in which a response of interest is influenced by several variables and the objective is to optimize this response, in a suitable set of experiments (3). This strategy was employed in order to improve the production of both, biomass and ELP`s, in an auto induction medium previously designed by us (adapted from Terrific Broth and Phosphate Buffer Glycerol). The nutrients yeast extract, lactose and glycerol were the factors subjected to this statistical treatment. Knowing that glycerol and lactose are, respectively, sub-products of biodiesel production and dairy industry, the use of these compounds is highly favorable for the design of a sustainable scale-up procedure. On the other hand, yeast extract was selected in order to maximize the final yield due to it`s described importance in the boost of production.
The validation of the model obtained was achieved and allowed the optimization of biomass levels.info:eu-repo/semantics/publishedVersio
Sensitive areas under radium/uranium mine drainage - the Picoto mine case study, central Portugal
A zona mineira de Picoto está localizada próximo de Vilar Seco (Viseu, Centro de Portugal). Ocorre numa área de declive suave, altitude variando entre 360-380 m, incluÃda na bacia do rio Cagavaio, com drenagem dominante NE-SW. A mineralização ocorre em veios de quartzo, que intersectam o granito Varisco, porfiróide de duas micas. Os filões de quartzo preenchem falhas N37°-45°E e N50°-70°E, localmente brechificadas. Estes filões contêm meta-torbernite e uranófano, e alguns minerais portadores de U, como clorite e hidróxidos de Fe e Mn. A exploração ocorreu em duas fases, entre 1917 e 1953. Após cessada a exploração, permaneceram as escombreiras resultantes da exploração e a área nunca foi reabilitada. Neste momento, está ocupada por culturas locais, principalmente vinhas e produtos agrÃcolas. Vinte amostras de águas superficiais e subterrâneas foram colhidas entre 2008 e 2009. Em geral, as águas apresentam valores de pH entre 4.7 a 6.3 e são pouco mineralizadas (CE = 44-190 μS/cm; TDS = 49-137 mg/L). Contudo, algumas águas estão contaminadas em NO2, Fe, Mn, Cu, As e U, e não devem ser utilizadas para consumo humano nem em atividades agrÃcolas. A contaminação da água está associada principalmente à antiga mina de rádio/urânio e atividades humanas desenvolvidas.The Picoto mine area is located at Vilar Seco village (Viseu, central Portugal), in a soft slope area with altitudes ranging from 360 to 380 m, included in the Cagavaio river catchment, with a dominant NE-SW drainage. The mineralization occurs mainly in quartz veins, which intersect a Variscan porphyritic two-mica granite. The quartz veins fill N37°-45°E and N50°-70°E faults, locally brecciated. The quartz veins contain meta-torbernite and uranophane, and some U-bearing minerals, such as chlorite and Fe- and Mn-hydroxides. The exploitation was carried out in two stages, between 1917 and 1953. Since closure, the area contains mine rejected materials and has never been restored. Therefore, a local cultivated area, mainly for vines and domestic consumption agricultural products, is now deployed. A total of twenty surface and groundwater samples were collected between 2008 and 2009. In general, the waters yield pH values ranging from 4,4 to 6,3 and are poorly mineralized (EC=44-190 µS/cm; TDS= 49-137 mg/L). However, some waters are contaminated with NOâ‚‚, Fe, Mn, Cu, As and U and must not be used neither for human consumption nor in agricultural activities. The water contamination is mainly associated with the old radium/uranium mine and subsequent human activities developed in the area.Este trabalho teve suporte financeiro através do ICT e do projeto UID/GEO/04035/2013.info:eu-repo/semantics/publishedVersio
New steroidal aromatase inhibitors: Suppression of estrogen-dependent breast cancer cell proliferation and induction of cell death
<p>Abstract</p> <p>Background</p> <p>Aromatase, the cytochrome P-450 enzyme (CYP19) responsible for estrogen biosynthesis, is an important target for the treatment of estrogen-dependent breast cancer. In fact, the use of synthetic aromatase inhibitors (AI), which induce suppression of estrogen synthesis, has shown to be an effective alternative to the classical tamoxifen for the treatment of postmenopausal patients with ER-positive breast cancer. New AIs obtained, in our laboratory, by modification of the A and D-rings of the natural substrate of aromatase, compounds <b>3a </b>and <b>4a</b>, showed previously to efficiently suppress aromatase activity in placental microsomes. In the present study we have investigated the effects of these compounds on cell proliferation, cell cycle progression and induction of cell death using the estrogen-dependent human breast cancer cell line stably transfected with the aromatase gene, MCF-7 aro cells.</p> <p>Results</p> <p>The new steroids inhibit hormone-dependent proliferation of MCF-7aro cells in a time and dose-dependent manner, causing cell cycle arrest in G<sub>0</sub>/G<sub>1 </sub>phase and inducing cell death with features of apoptosis and autophagic cell death.</p> <p>Conclusion</p> <p>Our <it>in vitro </it>studies showed that the two steroidal AIs, <b>3a </b>and <b>4a</b>, are potent inhibitors of breast cancer cell proliferation. Moreover, it was also shown that the antiproliferative effects of these two steroids on MCF-7aro cells are mediated by disrupting cell cycle progression, through cell cycle arrest in G<sub>0</sub>/G<sub>1 </sub>phase and induction of cell death, being the dominant mechanism autophagic cell death. Our results are important for the elucidation of the cellular effects of steroidal AIs on breast cancer.</p
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