256 research outputs found
Endothelial Cell-Astrocyte Interactions
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75690/1/j.1749-6632.1988.tb51417.x.pd
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Community Resource for Innovation in Polymer Technology (CRIPT): A Scalable Polymer Material Data Structure
Polymeric materials are integral components of nearly every aspect of modern life. However, developing cheminformatic solutions for polymers has been difficult since they are large stochastic molecules with hierarchical structures spanning multiple length scales. Here we present the design for a general material data model that underpins the Community Resource for Innovation in Polymer Technology (CRIPT) data ecosystem
A ‘quiet revolution’? The impact of Training Schools on initial teacher training partnerships
This paper discusses the impact on initial teacher training of a new policy initiative in England: the introduction of Training Schools. First, the Training School project is set in context by exploring the evolution of a partnership approach to initial teacher training in England. Ways in which Training Schools represent a break with established practice are considered together with their implications for the dominant mode of partnership led by higher education institutions (HEIs). The capacity of Training Schools to achieve their own policy objectives is examined, especially their efficacy as a strategy for managing innovation and the dissemination of innovation. The paper
ends by focusing on a particular Training School project which has adopted an unusual approach to its work and enquires whether this alternative approach could offer a more profitable way forward. During the course of the paper, five different models of partnership are considered:
collaborative, complementary, HEI-led, school-led and partnership within a partnership
A relevant in vitro rat model for the evaluation of blood-brain barrier translocation of nanoparticles
Poly(MePEG2000cyanoacrylate-co-hexadecylcyanoacrylate) (PEG-PHDCA) nanoparticles have demonstrated their capacity to reach the rat central nervous system after intravenous injection. For insight into the transport of colloidal systems across the blood-brain barrier (BBB), we developed a relevant in vitro rat BBB model consisting of a coculture of rat brain endothelial cells (RBECs) and rat astrocytes. The RBECs used in our model displayed and retained structural characteristics of brain endothelial cells, such as expression of P-glycoprotein, occludin and ZO-1, and immunofluorescence studies showed the specific localization of occludin and ZO1. The high values of transendothelial electrical resistance and low permeability coefficients of marker molecules demonstrated the functionality of this model. The comparative passage of polyhexadecylcyanoacrylate and PEG-PHDCA nanoparticles through this model was investigated, showing a higher passage of PEGylated nanoparticles, presumably by endocytosis. This result was confirmed by confocal microscopy. Thanks to a good in vitro/in vivo correlation, this rat BBB model will help in understanding the mechanisms of nanoparticle translocation and in designing new types of colloidal carriers as brain delivery systems
Action potentials in abscisic acid-deficient tomato mutant generated spontaneously and evoked by electrical stimulation
Action potentials generated spontaneously (SAPs) and evoked by electrical stimulation (APs) in tomato plants (Solanum lycopersicum L.) cv. Micro-Tom ABA-deficient mutants (sitiens—MTsit) and its wild type (MTwt) were characterized by continuous monitoring of electrical activity for 66 h and by application of an electrical stimulation supplied extracellularly. MTsit generated SAPs which spread along the stem, including petioles and roots with an amplitude of 44.6 ± 4.4 mV, half-time (t½) of 33.1 ± 2.9 s and velocity of 5.4 ± 1.0 cm min−1. Amplitude and velocity were 43 and 108 % higher in MTsit than in MTwt, respectively. The largest number of SAPs was registered in the early morning in both genotypes. MTsit was less responsive to electrical stimuli. The excitation threshold and the refractory period were greater in MTsit than in MTwt. After current application, APs were generated in the MTwt with 21.2 ± 2.4 mV amplitude and propagated with 5.6 ± 0.5 cm min−1 velocity. Lower intensity stimuli did not trigger APs in these plants. In MTsit APs were measured with amplitude of 26.8 ± 4.8 mV and propagated with velocity of 8.5 ± 0.1 cm min−1
Efeitos de retardadores de crescimento na frutificação da videira 'Niagara Rosada'
Studies were carried out to establish the effects of exogenous growth regulators on Vitis (labrusca x vinifera) 'Niagara Rosada' fruiting. The investigations were done in the Jundiaà Research Station, Agronomic Institute State of São Paulo, always using disease-free vineyards of good productivity. The morphological transformations of clusters were studied under the following aspects: weight, length and width of cluster; weight, length average and width average of berries: length average/width average ratio of berries; length and diameter of rachis; width of cluster minus berries; length and diameter of secondary rachis. The yield for the first half of the period from flowering to maturation was first determined. The same characteristics were determined at the time of maturity plus the number of berries, number of seeds, total sugars, total acid, Maturity Index and reducing sugars in samples of all treatments. The experiment was conducted in order to determine the doses that resulted in the most beneficial effects, always using applications by immersion of the inflorescence. In the experiment was realized applications of (2-chloroethyl) trimethylammonium chloride (CCC) and succinic aeid-2, 2-dimethylhydrazide (SADH) at concentrations of 50, 100, 250, 500, 1000 and 2000 ppm; CCC 500 ppm plus SADH 500 ppm and nontreated, 5 days before flowering, in 1971. The concentrations of CCC applied before flowering did not affect favorably cluster morphology under the conditions of the experiment. Application of SADH at 250 ppm before flowering increased the cluster weight and length, berries number and weight, and seed number. In the first yield treatment of 1000 ppm of SADH increased the cluster weight and lenght, berry weight and rachis lenght.Estudou-se a influência da aplicação por imersão, de retardadores de crescimento (CCC e SADH), 5 dias antes do florescimento, nas caracterÃsticas morfológicas da panÃcuia da videira Vitis (labrusca x vinifera) 'Niagara Rosada'. Neste ensaio verificou-se que as concentrações de CCC aplicadas em pré-florescimento, não afetaram favoravelmente a morfologia das panÃculas da cultivar estudada, nas condições do ensaio. SADH na dosagem de 1000 ppm provocou, na primeira colheita, aumento no peso e comprimento da panÃcula, no peso das bagas, e no comprimento da ráquis, proporcionando a formação desejada de uma panÃcula mais alongada, nas condições estudadas. Aplicação de SADH na concentração de 250 ppm em pré-florescimento, promoveu aumento no peso e comprimento da panÃcula, número e peso das bagas, além do inconveniente de elevar o número de sementes
On the Integration of Carbon Capture and Storage into the International Climate Regime
As GHG emissions did not decline as anticipated early of the 1990ties Carbon Capture and Storage (CCS) recently gained more and more attention as a climate change mitigation option. However, CO2 suppressed in geological reservoirs is likely to lead to future releases of the CO2 stored. This „non-permanence“ must be considered if an environmentally sound policy is desired. Against this background, the present article analyses a potential integration of CCS in the international climate regime. It is based on existing rules and modalities regarding non-permanence of sequestration in the Land use, Land-use change and Forestry (LULUCF) sector. Interestingly, the experience from LULUCF has almost completely been neglected during the discussion on CCS. We argue that CCS can only be accounted for in a transparent and comprehensive way, if it is considered a „removal“ (or „sink“) activity. This is, however, incompatible with the current UNFCCC rules and definitions. Consequently, they would have to be changed. Accounting and problems of cross-border projects are discussed. They arise due to the potential geographical separation of capture and storage site. Furthermore, an economic analysis is conducted considering the consequences of non-permanent storage. We apply the tCER approach for LULUCF projects which has already been agreed upon during the international climate negotiations. It may thus form the basis for CCS, too. The study suggests that CCS is probably not as attractive as widely claimed
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