Review of R&D progress and practical application of the solar photovoltaic/thermal (PV/T) technologies

In this paper, the global market potential of solar thermal, photovoltaic (PV) and combined photovoltaic/thermal (PV/T) technologies in current time and near future was discussed. The concept of the PV/T and the theory behind the PV/T operation were briefly introduced, and standards for evaluating technical, economic and environmental performance of the PV/T systems were addressed. A comprehensive literature review into R&D works and practical application of the PV/T technology was illustrated and the review results were critically analysed in terms of PV/T type and research methodology used. The major features, current status, research focuses and existing difficulties/barriers related to the various types of PV/T were identified. The research methods, including theoretical analyses and computer simulation, experimental and combined experimental/theoretical investigation, demonstration and feasibility study, as well as economic and environmental analyses, applied into the PV/T technology were individually discussed, and the achievement and problems remaining in each research method category were described. Finally, opportunities for further work to carry on PV/T study were identified. The review research indicated that air/water-based PV/T systems are the commonly used technologies but their thermal removal effectiveness is lower. Refrigerant/heat-pipe-based PV/Ts, although still in research/laboratory stage, could achieve much higher solar conversion efficiencies over the air/water-based systems. However, these systems were found a few technical challenges in practice which require further resolutions. The review research suggested that further works could be undertaken to (1) develop new feasible, economic and energy efficient PV/T systems; (2) optimise the structural/geometrical configurations of the existing PV/T systems; (3) study long term dynamic performance of the PV/T systems; (4) demonstrate the PV/T systems in real buildings and conduct the feasibility study; and (5) carry on advanced economic and environmental analyses. This review research helps finding the questions remaining in PV/T technology, identify new research topics/directions to further improve the performance of the PV/T, remove the barriers in PV/T practical application, establish the standards/regulations related to PV/T design and installation, and promote its market penetration throughout the world.

ON INTEGRABLE CODIMENSION ONE ANOSOV ACTIONS OF R(k)

In this paper, we consider codimension one Anosov actions of R(k), k >= 1, on closed connected orientable manifolds of dimension n vertical bar k with n >= 3. We show that the fundamental group of the ambient manifold is solvable if and only if the weak foliation of codimension one is transversely affine. We also study the situation where one 1-parameter subgroup of R(k) admits a cross-section, and compare this to the case where the whole action is transverse to a fibration over a manifold of dimension n. As a byproduct, generalizing a Theorem by Ghys in the case k = 1, we show that, under some assumptions about the smoothness of the sub-bundle E(ss) circle plus E(uu), and in the case where the action preserves the volume, it is topologically equivalent to a suspension of a linear Anosov action of Z(k) on T(n).

Transitivity of codimension-one Anosov actions of R(k) on closed manifolds

We consider Anosov actions of R(k), k >= 2, on a closed connected orientable manifold M, of codimension one, i.e. such that the unstable foliation associated to some element of R(k) has dimension one. We prove that if the ambient manifold has dimension greater than k + 2, then the action is topologically transitive. This generalizes a result of Verjovsky for codimension-one Anosov flows.

Foliations and polynomial diffeomorphisms of R(3)

Let Y = (f, g, h): R(3) -> R(3) be a C(2) map and let Spec(Y) denote the set of eigenvalues of the derivative DY(p), when p varies in R(3). We begin proving that if, for some epsilon > 0, Spec(Y) boolean AND (-epsilon, epsilon) = empty set, then the foliation F(k), with k is an element of {f, g, h}, made up by the level surfaces {k = constant}, consists just of planes. As a consequence, we prove a bijectivity result related to the three-dimensional case of Jelonek`s Jacobian Conjecture for polynomial maps of R(n).

Duplication of R&D and industry concentration

The purpose of the literature on Research Joint Ventures (RJV), pioneered by DíAspremont and Jacquemin (1988) and Kamien, Muller, and Zang (1992), has been to combine the best of two worlds: to appropriately deal with R&D spillovers while preserving competition in the product market. Moreover, RJVs eliminate duplication of R&D. Thus, at least in theory, RJVs dominate other solutions such as subsidies. If, however, we are concerned about risks of cartelization, then Spenceís (1984) subsidy-based solution for independently acting firms, is a viable alternative that cannot be dismissed. Indeed, in contrast to the previous literature, we find that in the presence of R&D subsidies, market performance may unambiguously improve with the number of firms in the market.

Prediction of R plus R-2 gravity for the deflection of a photon passing close to the Sun

The cross-section for the scattering of a photon by the Sun's gravitational field, treated as an external field, is computed in the framework of R + R-2 gravity. Using this result, we found that for a photon just grazing the Sun's surface the deflection is 1.75 which is exactly the same as that given by Einstein's theory. An explanation for this pseudo-paradox is provided.

Bending of light in the framework of R + R2 gravity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Signatures of spontaneous breaking of R-parity in gluino cascade decays at LHC

We study the pattern of gluino cascade decays in a class of supersymmetric models where R-parity is spontaneously broken. We give a detailed discussion of the R-parity violating decays of the lightest neutralino, the second lightest neutralino and the lightest chargino. The multi-lepton and same-sign dilepton signal rates expected in these models are compared with those predicted in the Minimal Supersymmetric Standard Model. We show that these rates can be substantially enhanced in broken R-parity models. © 1997 Elsevier Science B.V.

Integration of R&D and new product development: case studies of Brazilian high-tech firms

One of the aspects that influence good performance of new product development (NPD) at high-tech companies is the integration of research and development (R&D) and the other functions involved with NPD. The objective of this paper is to examine why Brazilian medium and large sized high-tech companies are different with respect to the integration of R&D with NPD. An analysis of case studies was conducted at five Brazilian high-tech firms. Among the results, collectivism, which is characteristic of the Brazilian organisational culture, was seen to manifest itself in companies through the adoption of cross-functional teams; the valorisation of personal relations, which is stimulated by physical proximity; and project managers’ ample participation in different functions involving NPD.

The impact of R&D in firm value across Europe

In this thesis the impact of R&D expenditures on firm market value and stock returns is examined. This is performed in a sample of European listed firms for the period 2000-2009. I apply different linear and GMM econometric estimations for testing the impact of R&D on market prices and construct country portfolios based on firms’ R&D expenditure to market capitalization ratio for studying the effect of R&D on stock returns. The results confirm that more innovative firms have a better market valuation,investors consider R&D as an asset that produces long-term benefits for corporations. The impact of R&D on firm value differs across countries. It is significantly modulated by the financial and legal environment where firms operate. Other firm and industry characteristics seem to play a determinant role when investors value R&D. First, only larger firms with lower financial leverage that operate in highly innovative sectors decide to disclose their R&D investment. Second, the markets assign a premium to small firms, which operate in hi-tech sectors compared to larger enterprises for low-tech industries. On the other hand, I provide empirical evidence indicating that generally highly R&D-intensive firms may enhance mispricing problems related to firm valuation. As R&D contributes to the estimation of future stock returns, portfolios that comprise high R&D-intensive stocks may earn significant excess returns compared to the less innovative after controlling for size and book-to-market risk. Further, the most innovative firms are generally more risky in terms of stock volatility but not systematically more risky than low-tech firms. Firms that operate in Continental Europe suffer more mispricing compared to Anglo-Saxon peers but the former are less volatile, other things being equal. The sectors where firms operate are determinant even for the impact of R&D on stock returns; this effect is much stronger in hi-tech industries.

Role of (R)-9-hydroxystearic acid in zebrafish development

9-hydroxystearic acid (9-HSA) belongs to a class of lipid peroxidation products identified in several human and murine cell lines. These products are greatly diminished in tumors compared to normal tissues and their amount is inversely correlated with the malignancy of the tumor. 9-HSA activity has been tested in cancer cell lines, where it showed to act as a histone deacetylase 1 (HDAC1) inhibitor. In particular, in a colon cancer cell line (HT29), its administration resulted in an inhibition of proliferation together with an induction of differentiation. In this thesis the effect of (R)-9-hydroxystearic acid has been tested in vivo on cell proliferation and differentiation processes, in the early stages of zebrafish development. The final aim of this work was to elucidate the role of (R)-9-HSA in the control of cell differentiation and proliferation during normal development, in order to better understand its molecular control of cancerogenesis. The molecule has been administered via injection in the yolk of zebrafish embryos. The analysis of the histone acetylation pattern showed a hyperacetilation of histone H4 after treatment with the molecule, as detectable in HDAC1 mutants. (R)-9-HSA was also demonstrated to interfere with the signaling pathways that regulate proliferation and differentiation in zebrafish retina and hindbrain. This resulted in a reduction of proliferation in the hindbrain at 24 hours post injection (hpi), and in a hyperproliferation at 48 and 72 hpi in the retina, with a concomitant inhibition of differentiation. Finally, (R)-9-HSA effects were evident on proliferation of stem cell located in the ciliary marginal zone (CMZ) of the retina. The presence of ROS and 4-hydroxynoneal in the CMZ of wild-type embryos supports the hypothesis that oxidative stress could regulate stem cells fate in zebrafish retina.