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51.
The method of affinity coelectrophoresis was used to study the binding of nine representative glycosaminoglycan (GAG)-binding proteins, all thought to play roles in nervous system development, to GAGs and proteoglycans isolated from developing rat brain. Binding to heparin and non-neural heparan and chondroitin sulfates was also measured. All nine proteins-laminin-1, fibronectin, thrombospondin-1, NCAM, L1, protease nexin-1, urokinase plasminogen activator, thrombin, and fibroblast growth factor-2-bound brain heparan sulfate less strongly than heparin, but the degree of difference in affinity varied considerably. Protease nexin-1 bound brain heparan sulfate only 1.8-fold less tightly than heparin (Kdvalues of 35 vs. 20 nM, respectively), whereas NCAM and L1 bound heparin well (Kd approximately 140 nM) but failed to bind detectably to brain heparan sulfate (Kd>3 microM). Four proteins bound brain chondroitin sulfate, with affinities equal to or a few fold stronger than the same proteins displayed toward cartilage chondroitin sulfate. Overall, the highest affinities were observed with intact heparan sulfate proteoglycans: laminin-1's affinities for the proteoglycans cerebroglycan (glypican-2), glypican-1 and syndecan-3 were 300- to 1800-fold stronger than its affinity for brain heparan sulfate. In contrast, the affinities of fibroblast growth factor-2 for cerebroglycan and for brain heparan sulfate were similar. Interestingly, partial proteolysis of cerebroglycan resulted in a >400-fold loss of laminin affinity. These data support the views that (1) GAG-binding proteins can be differentially sensitive to variations in GAG structure, and (2) core proteins can have dramatic, ligand-specific influences on protein-proteoglycan interactions. 相似文献
52.
In early 2002, the Swedish National Food Administration reported high acrylamide levels in heat-treated carbohydrate-rich foods. Consequently, intensive activity began examining the many different types of food, and thousands of analyses have been undertaken world wide. Measurement data have been published in many different types of media. Within this flood of publications, there are only a limited number of articles concerned with the technical aspects of the measurements. This review focuses on the state-of-the-art in the analysis of acrylamide in foodstuffs. It covers information on methods from peer-reviewed articles and other sources (e.g. a survey carried out among official and private laboratories of the Member States of the European Union). Alternative methods are presented and discussed alongside the more common measurement techniques for acrylamide in foodstuffs. Special attention is given to sample preparation. The greatest differences between the analytical methods was for acrylamide extraction and clean-up. The influence of different extraction techniques or extraction solvents/solvent mixtures on the measurement results has not yet been fully investigated. There is also a lack of understanding about the sample clean-up. Since both might have a large impact on the results of the analysis, this review should also be considered as a basis for further investigations. 相似文献
53.
Jaime M. Martin S. García F. Calle I. Mártil G. Gonzalez-Diaz 《Journal of Electronic Materials》1995,24(1):59-67
Mg, Mg/P, and Mg/Ar implantations were performed into InP:Fe with an energy of 80 keV for obtaining shallow p+ layers suitable for device applications. After rapid thermal annealing at 850 or 875°C for 5 or 10 s, activations between
10 and 50% and mobilities as high as 110 cm2/Vs were obtained for the different doses employed. For the implantations with 1014 cm−2, differential Hall measurements showed hole profiles with peak concentrations in the mid-1018 cm-3 range and Hall mobilities of 90 cmWs. However, secondary ion mass spectrometry profiles showed a clear pileup of Mg at the
surface and in-diffusion tails deeper than 2 μ. Phosphorus or Ar co-implantation reduced the Mg in-diffusion and increased
the activation, but not as clearly as in the case of Be implants. Photoluminescence (PL) measurements demonstrated the good
crystalline quality of the material after all the annealing cycles employed. In the photoluminescence spectra, together with
narrow emissions close to the gap wavelength, two broad bands, centered at about 1.3 and 0.87 eV were found, this last being
the dominant emission of the PL spectra from the layers with higher implanted doses. The origin of this band is tentatively
assigned to complexes involving Mg and a defect. 相似文献
54.
CW Heath CA Lally EE Calle JK McLaughlin MJ Thun 《Canadian Metallurgical Quarterly》1997,145(7):607-613
We identified the serotypes and genomes patterns of 100 strains of Pseudomonas aeruginosa (P. aeruginosa) that had been isolated from patients who were admitted to the hospital of the Fukui Medical School between 1992 and 1995. A monoclonal diagnostic kit was used to identify the serotypes. Genome patterns were determined by pulsed field gel electrophoresis (PFGE). Serotypes A, B, C, D, E, F, G and I exhibited distinct genome patterns. Differences in genome patterns were also observed in strains of serotypes E and G, depending on the types of clinical samples collected and/or the area of the hospital from which they were isolated. Many of the multiple antibiotic-resistant strains of P. aeruginosa exhibited serotype E. The genome pattern differed between strains that were susceptible vs. resistant to multiple antibiotics. The latter strains exhibited similar genome patterns regardless of their origin. These findings suggest that analysis of genome patterns is important for identifying the origin of nosocomial infection caused by P. aeruginosa, serotype E. 相似文献
55.
A. Calle J. -L. Casanova F. González-Alonso 《International journal of remote sensing》2013,34(17):4567-4579
The spatial resolution of sensors is a concept frequently described in an inappropriate way, usually identified by the sampling distance in the image capturing process. The shape of the modulation transfer function (MTF) has no influence on the results in applications based on homogeneous distribution of radiance. However, in the case of high-temperature events (HTEs), the spatial location of the burning area inside the pixel is a key issue to solve, in order to quantify the radiance. The point spread function (PSF) should be considered both in fire detection-oriented algorithms and in the application of bispectral processes. This paper analyses the impact of the PSF of the Meteosat Second Generation Spinning Enhanced Visible and Infrared Imager (MSG-SEVIRI) sensor on the determination of thermal fire parameters. The PSF influence on the brightness temperature (BT), in the mid-infrared (MIR) 3.9 μm spectral band, on detection algorithms is analysed. Errors in the fire temperature retrieved by the bispectral technique, due to non-coincidence in the PSF involved, are also analysed. The results obtained show a difference of around 20 K in the BT in the 3.9 μm spectral band, depending on the fire location inside the pixel. Finally, the probability detection of the minimal size of the burning area was analysed, and revealed that there is a 90% probability of detecting a fire with a burning area of 10 ha whereas an area of 4 ha is detected with a probability of 50%. 相似文献
56.
In this work, we analyze the influence of the processing pressure and the substrate?Ctarget distance on the synthesis by reactive sputtering of c-axis oriented polycrystalline aluminum nitride thin films deposited on Si(100) wafers. The crystalline quality of AlN has been characterized by high-resolution X-ray diffraction (HR-XRD). The films exhibited a very high degree of c-axis orientation especially when a low process pressure was used. After growth, residual stress measurements obtained indirectly from radius of curvature measurements of the wafer prior and after deposition are also provided. Two different techniques are used to determine the curvature??an optically levered laser beam and a method based on X-ray diffraction. There is a transition from compressive to tensile stress at a processing pressure around 2?mTorr. The transition occurs at different pressures for thin films of different thickness. The degree of c-axis orientation was not affected by the target?Csubstrate distance as it was varied in between 30 and 70?mm. 相似文献
57.
R. Cuerdo J. Pedrós A. Navarro A. F. Braña J. L. Pau E. Muñoz F. Calle 《Journal of Materials Science: Materials in Electronics》2008,19(2):189-193
The high temperature characterization of GaN-based devices, including high electron mobility transistors (HEMTs), p-i-n photodiodes
and surface acoustic wave (SAW) filters is reported. Transmission line method (TLM) measurements reveal the reversible behaviour
of both the ohmic contact resistance and the two-dimensional electron gas (2DEG) mobility. AlGaN/GaN HEMTs on sapphire and
SiC substrates present a reduction of the drain current and the transconductance as temperature increases. The responsivity
of InGaN/GaN photodiodes is enhanced and shifted to larger wavelengths with temperature, recovering its original value after
the thermal cycle. The temperature coefficient of frequency of SAW filters on AlN epilayers on different substrates has been
measured. The influence of temperature on the different surface acoustic modes is compared. 相似文献
58.
Podosomes are specialized adhesion sites found in rapidly migrating and invasive cells, most notably in cells from the myeloid lineage that participate in immune surveillance and phagocyte defence mechanisms. In this review, we describe the nature of leukocyte podosomes and the regulation of their turnover during migration by the key regulatory molecules Wiskott-Aldrich syndrome protein and WASP-interacting protein. 相似文献
59.
Frank Rosillo‐Calle 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2016,91(7):1933-1945
Biomass has been, historically, the main source of global energy, primarily for cooking, heating, and small cottage industries. It is witnessing a strong revival and is currently used in a multitude of applications. It provides between 10 and 14% of world energy, with the potential to provide 30–40 + % and is an integral component of all energy scenarios. Biomass energy is providing multiple energy, environmental, and socio‐economic benefits, both modern and traditional, ranging from electricity, heat, to transportation fuels. This review provides a critical assessment of biomass energy literature. It is not an analysis of biomass energy production and conversion methods. The main themes covered are: (i) biomass energy potential and its uses; (ii) liquid biofuels for transportation; (iii) land use changes implications; (iv) the food versus fuel debate; (v) environmental and sustainability, subsidies and energy balance issues; and (vi) international biomass energy trade. An additional key concern of this review has been to identify the main shortcomings and concerns affecting biomass energy of themes stated above, e.g. problems posed by poor scientific data, land use change, food versus biofuel debate; environmental and sustainability implications, or potential impacts of international biomass energy trade. Given the broad nature of biomass energy, and the need to embraces all major issues, this review paper is in many ways an overview. © 2016 Society of Chemical Industry 相似文献
60.
Diana Suárez-Boomgaard Belén Gago Alejandra Valderrama-Carvajal Ruth Roales-Buján Kathleen Van Craenenbroeck Jolien Duchou Dasiel O. Borroto-Escuela José Medina-Luque Adelaida de la Calle Kjell Fuxe Alicia Rivera 《International journal of molecular sciences》2014,15(1):1481-1498
The mu opioid receptor (MOR) is critical in mediating morphine analgesia. However, prolonged exposure to morphine induces adaptive changes in this receptor leading to the development of tolerance and addiction. In the present work we have studied whether the continuous administration of morphine induces changes in MOR protein levels, its pharmacological profile, and MOR-mediated G-protein activation in the striosomal compartment of the rat CPu, by using immunohistochemistry and receptor and DAMGO-stimulated [35S]GTPγS autoradiography. MOR immunoreactivity, agonist binding density and its coupling to G proteins are up-regulated in the striosomes by continuous morphine treatment in the absence of changes in enkephalin and dynorphin mRNA levels. In addition, co-treatment of morphine with the dopamine D4 receptor (D4R) agonist PD168,077 fully counteracts these adaptive changes in MOR, in spite of the fact that continuous PD168,077 treatment increases the [3H]DAMGO Bmax values to the same degree as seen after continuous morphine treatment. Thus, in spite of the fact that both receptors can be coupled to Gi/0 protein, the present results give support for the existence of antagonistic functional D4R-MOR receptor-receptor interactions in the adaptive changes occurring in MOR of striosomes on continuous administration of morphine. 相似文献