5,428 research outputs found
Evaluación y uso de razas ovinas recientemente introducidas al Uruguay
Get PDFTribunal: Álvarez, Juan Mauricio; Guillena, Ana; De Barbieri, IgnacioEl número de ovinos en Uruguay ha disminuido sostenidamente en los últimos 30 años. En el norte y el noreste existen sistemas extensivos productores de lana fina y de doble propósito respectivamente, donde tanto la lana como la carne impactan en los ingresos. En el sur han prosperado sistemas familiares de producción de carne ovina en pequeña escala. En esta tesis presento trabajos realizados en sistemas de producción de las regiones sur (1) y noreste (2). Corriedale (C) es la raza mayoritaria en el país. Milchschaf (M) se ha difundido en el sur, pero C predomina en el noreste. Hay escasez de evaluaciones rigurosas de estas razas o alternativas que podrían ser más rentables, como Highlander (H) para el sur y Merino Dohne (MD) para el noreste. En los experimentos evalué: en 1), la producción de lana, la reproducción y el crecimiento en C, H y M, y en 2), la calidad de la lana y rasgos corporales en borregas del cruzamiento rotacional entre C y MD. En 1), la producción de lana fue mejor en C, pero H y M superaron a C en peso vivo y desempeño reproductivo. En 2), los genotipos con mayor proporción de MD produjeron menor peso de vellón y los de mayor proporción de C fibras de mayor diámetro, sin diferencias en calidad de lana ni en rasgos morfológicos relacionados a la aptitud carnicera. Los márgenes brutos (MB) integran el rendimiento físico con valores y costos de la producción, permitiendo la comparación monetaria entre genotipos. Calculé los MB para varios escenarios de producción y mercado. En 1), la mayoría de las veces, el MB fue mayor para H, seguido de M. Las diferencias a favor de H y M sobre C disminuyeron cuando consideré mayores requerimientos de alimento para H y M. El MB de H y M aumentó al suponer que no tenían lana (el costo de cosecha supera el valor de la lana producida). En 2), consideré precios bajos y altos para lana de diferente diámetro de fibra. El MB fue mayor para ¾MD y ½MD a precios bajos, y para ¾MD y ½MD a precios altos. C tuvo el menor MB en todos los escenarios. Recomiendo H para los sistemas del sur e investigar sobre las razas ovinas de pelo. En los sistemas extensivos de doble propósito, el cruzamiento rotacional entre C y MD permite mejorar los ingresos por lana sin perder potencial carnicero. Formulo recomendaciones sobre futuras evaluaciones de genotipos, integrándolas con las actuales evaluaciones genéticas dentro de raza
Receiver Windowing Design for Narrowband Interference Mitigation in MB-OFDM UWB System
No full textIn 2005, the WiMedia Alliance working with the European Computer Manufacturers Association (ECMA) announced the establishment of the WiMedia MB-OFDM (Multiband Orthogonal Frequency Division Multiplexing) UWB radio platform as their global UWB standard. It was also chosen as the physical layer (PHY) of high data rate wireless specifications for high speed Wireless USB (W-USB), Bluetooth 3.0 and Wireless High-Definition Media Interface (HDMI). However, due to the low power and wide bandwidth nature of UWB systems, in-band narrowband interference (NBI) may hinder the receiver performance. This thesis presents an analysis of NBI impact on the MB-OFDM system for UWB communication. The intent of our analysis is to provide practical solutions for interference mitigation under different NBI models. In our work, a new receiver windowing for zero padding (ZP) OFDM system is proposed to reduce NBI spreading in the MB-OFDM UWB system. Simulations demonstrate the effectiveness of windowing under different NBI models.Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
Altered immunolocalization of FGF23 in murine femora metastasized with human breast carcinoma MDA-MB-231 cells
Get PDFIntroduction After the onset of bone metastasis, tumor cells appear to modify surrounding microenvironments for their benefit, and particularly, the levels of circulating fibroblast growth factor (FGF) 23 in patients with tumors have been highlighted. Materials and methods We have attempted to verify if human breast carcinoma MDA-MB-231 cells metastasized in the long bone of nu/nu mice would synthesize FGF23. Serum concentrations of calcium, phosphate (Pi) and FGF23 were measured in control nu/nu mice, bone-metastasized mice, and mice with mammary gland injected with MDA-MB-231 cells mimicking primary mammary tumors. Results and conclusions MDA-MB-231 cells revealed intense FGF23 reactivity in metastasized lesions, whereas MDA-MB-231 cells cultured in vitro or when injected into the mammary glands (without bone metastasis) showed weak FGF23 immunoreactivity. Although the bone-metastasized MDA-MB-231 cells abundantly synthesized FGF23, osteocytes adjacent to the FGF23-immunopositive tumors, unlike intact osteocytes, showed no FGF23. Despite significantly elevated serum FGF23 levels in bone-metastasized mice, there was no significant decrease in the serum Pi concentration when compared with the intact mice and mice with a mass of MDA-MB-231 cells in mammary glands. The metastasized femora showed increased expression and FGFR1 immunoreactivity in fibroblastic stromal cells, whereas femora of control mice showed no obvious FGFR1 immunoreactivity. Taken together, it seems likely that MDA-MB-231 cells synthesize FGF23 when metastasized to a bone, and thus affect FGFR1-positive stromal cells in the metastasized tumor nest in a paracrine manner
Selenium inclusion decreases oxidative stress indicators and muscle injuries in sea bass larvae fed high DHA microdiets.
No full textThe objective of the present study was to determine the effect of Se inclusion in high-DHA and vitamin E microdiets (5 g DHA/100 g dry
weight and 300mg vitamin E/100 g dry weight; 5 g DHA/100 g dry weight and 300mg vitamin E/100 g dry weight supplemented with Se) in
comparison with a control diet (1 g DHA/100 g dry weight and 150mg vitamin E/100 g dry weight) on sea bass larval growth,survival,biochemical composition,malonaldehyde (MDA) content,muscle morphology and antioxidant enzymes (AOE),insulin-like growth factors
(IGF) and myosin expression. For a given DHA and vitamin E dietary content,Se inclusion favoured larval total length and specific growth
rate,and reduced the incidence of muscular lesions,MDA contents and AOE gene expression. In contrast,IGF gene expression was elevated
in the 5/300 larvae,suggesting an increased muscle mitogenesis that was corroborated by the increase in mRNA copies of myosin
heavy chain. The results of the present study denoted the beneficial effect of Se not only in preventing oxidative stress,as a glutathione
peroxidase cofactor,but probably due to other as yet unknown physiological functions
ASIC FFT processor for MB-OFDM UWB system
No full textThe physical layer (PHY) standard of Multi-band Orthogonal Frequency Division Multiplexing (MB-OFDM) Ultra Wideband (UWB) system was defined by ECMA International. In this standard, the data sampling rate from the analog-to-digital converter to the physical layer is up to 528 Msample/s. Therefore, it is a challenge to realize the physical layer of the UWB system-especially the components with high computational complexity in Very Large Scale Integration (VLSI) implementation. Fast Fourier Transform (FFT) block is one of these components. FFT plays an important role in Multi-band OFDM UWB system, which is the demodulation block of OFDM signals. The purpose of this project is to design an Application Specific Integrated Circuit (ASIC) FFT solution for this system. The specification is defined from the system analysis and literature research. All the design choices and considerations are concluded and explained.Based on the algorithm and architecture analysis, a novel Radix22Parallel processor is proposed, which is a small-area and low-power-consumption solution for MB-OFDM UWB system. Both Field Programmable Gate Array (FPGA) and ASIC targeted synthesis results of this architecture are presented.Electrical Engineering, Mathematics and Computer Scienc
Dietary selenium inclusion decreases oxidative stress indicators and muscle injuries in sea bass larvae fed high DHA microdiets.
No full textOne of the deleterious effect of oxidative stress found in sea bass larvae is the appearance of dystrophic lesions in the
epaxial musculature due to the ingestion of high DHA diets, especially when vitamin E levels are low (Betancor et al.,
2011; Betancor et al., submitted). Diverse antioxidant enzymes (AOE) prevent the cascade of oxidant reactions, intercepting
and inactivating with the reactive intermediates, closing the lipid-peroxidation cycle. This defence system includes
enzymes such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX) (Winston Halliwell and
Gutteridge, 1996). Together with these enzymes dietary micronutrients such as vitamin E and C, carotenoids or selenium
play important roles in antioxidant defences in fish. Adequate supplementation of marine fish larvae with antioxidants is
therefore an important issue in diet formulation in order to avoid in vivo lipid peroxidation. The purpose of the present
study was to investigate if diets supplemented with Se (5mg kg-1 DW) and vitamin E protects sea bass larvae muscle from
oxidative stress when high levels of DHA are included in diets. To reach this objective, growth, survival, TBARS, fatty acid
profile, α-tocopherol and selenium contents and mRNA expression of CAT, SOD, GPX, IGF-I and II and myosin heavy
chain (MyHC) were determined
Hollow and Cage-Bell Structured Nanomaterials of Noble Metals
No full textMastery of the structure of nanomaterials enables control
of their properties to enhance their performance for a given application.
Herein we demonstrate the synthesis of metal nanomaterials with hollow
interiors or cage-bell structures based on the inside-out diffusion
of Ag in core–shell structured nanoparticles. It begins with
the synthesis of core–shell Ag–M or core–shell–shell
MA–Ag–MB nanoparticles in an organic solvent.
Ag is then extracted from the core or the inner shell by bis(p-sulfonatophenyl)phenylphosphane,
which binds strongly with Ag(I)/Ag(0) to allow the complete removal
of Ag in 24–48 h, leaving behind an organosol of hollow or
cage-bell structured metal nanomaterials. Because of their relatively
lower densities, which usually translate to a higher surface area
than their solid counterparts, the hollow and cage-bell structured
metal nanomaterials are especially relevant to catalysis. For example,
cage-bell structured Pt–Ru nanoparticles were found to display
outstanding methanol tolerance for the cathode reaction of direct
methanol fuel cells (DMFCs) as a result of the differential diffusion
of methanol and oxygen in the cage-bell structure
Commodity Treatments: Responses of Tomatoes and Green Bell Peppers to Fumigation with Methyl Bromide or Ethylene Dibromide
Get PDFFumigation of tomatoes with methyl bromide (MB) at dosages that might be used for control of the Mediterranean fruit fly (Ceratitis capitata Wied.) slows the rate of ripening of mature-green fruit by about 20 percent and slightly increases their susceptibility to decay. Splotchy ripening occurred in only one cultivar treated at 32°C. Inorganic bromide residues in tomatoes were less than the legal tolerance of 20 parts per million, even at the maximum dosage of 48 g MB/m3. Green bell peppers were severely injured when fumigated with MB at a dosage effective against the Mediterranean fruit fly. Thus, MB is not a suitable fumigant for green peppers. Fumigation of green bell peppers with ethylene dibromide (EDB) increased the incidence of decay and induced slight surface pitting. However, at the dosage used, the defects induced by EDB are not serious enough to preclude the use of EDB as a fumigant for green peppers to meet quarantine requirements. At a dosage of 8 g EDB/m3, the inorganic bromide residue was less than 25 p/m
Characterization of the tertiary structure of the de novo designed protein MB-1
No full textMilk Bundle-1 (MB-1) is a de novo designed protein with 100 amino acids, having a molecular weight of 11.4 kilodaltons. MB-1 is enriched with 57% of selected essential amino acids (methionine, threonine, lysine and leucine), which are known to be limiting in dairy cattle. Recently, on the basis of a digestibility study, MB-1 was predicted to be unstable in rumen conditions.Characterization of the protein's structure was achieved using fluorescence spectroscopy (steady state measurements). MB-1 contains one tyrosine at position 62, expected to be in position "d" of helix III, in the hydrophobic core. Data obtained using fluorescence quenching indicates that the tyrosine is protected from the solvent in the putative hydrophobic core, as per design.Once it was established that MB-1 was not misfolded, further experiments were done to assess the fluidity of its hydrophobic core. For this, the amphiphillic dye ANSA was used. Results obtained for MB-1 compare favourably to those of many natural proteins, suggesting that MB-1 has achieved some degree of nativeness. Interestingly, MB-1 was found to exclude ANSA from its hydrophobic core more efficiently than all other de novo designed proteins reported to date.Finally, an analysis of folding thermodynamics of MB-1 was attempted. It was found that the fluorescence intensity of tyrosine was not sensitive to unfolding, making thermodynamic data impossible to obtain.Analysis of the data on MB-1 as compared to other natural proteins indicates that MB-1 is folded and compact. The lack of resistance to proteases must be caused by other factors other than the lack of compactness or misfolding. (Abstract shortened by UMI.).Source: Masters Abstracts International, Volume: 36-06, page: 1623.Adviser: Marc Beauregard
Atlantic Guardian, vol. 04, no. 04 (January 1948)
No full textHow Newfoundland voted on Confederation in 1869 / H. B. Mayo -- Newfoundland songs get an airing / Leslie R. Bell -- Newfoundland's labor governor / Brian Cahill -- Boss of the "lady" liners / W. D. Gilbert -- Bowring's new "Terra Nova" -- Guardian angles -- Stamps of Nfld. -- Books and such -- As others see Nfld.A popular magazine covering Newfoundland news and human interest stories with features such as Newfoundlanders Abroad, the Baby of the Month and community profiles, as well as poetry and short stories. Heavily illustrated with photographs. -- "Atlantic Guardian's platform: to make Newfoundland better known at home and abroad; to promote trade and travel in the Island; to encourage development of the Island's natural resources; to foster good relations between Newfoundland and her neighbors" (on all title pages after vol. 1, no. 4).Published monthly 1945-57, thereafter absorbed by the Atlantic Advocate (1952-92); suspended publication: October 1952-May 1953. Missing issues: vol. 14, nos. 7-8. -- An index to vols. 1-10 by author and/or article type is in vol. 11, no. 1 (January-February 1954), p. 33-48
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