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101.
Gallardo P Gaxiola G Soberano S Taboada JG Pérez M Rosas C Cuzon G Espinosa LG Sotelo A 《Journal of the science of food and agriculture》2012,92(11):2320-2325
BACKGROUND: Fish wastes has been used for many years as an alternative in feeds for aquaculture. In the present study weight gain of juvenile white shrimp Litopenaeus vannamei fed diets including fish waste silage (WS), fish waste silage with soybean meal SBM (WS + S) or fish waste meal (WM) was compared. A conventional acidic silage process was applied to obtain from wastes (skin, heads, bones and viscera) of snapper (Lutjanus spp.), grunt (Haemulon plumieri), and grouper (Epinephelus spp.) an ingredient rich in protein. RESULTS: After 3 days ensilage more than 90% protein was hydrolysed. Waste material processed at pH 3.8 lost about 24% tryptophan. Butylated hydroxytoluene (BHT) prevented lipid oxidation, as shown after 45 days with malonaldehyde production. Shrimp fed WS + S diet gained 0.7 g per week higher than those fed WS and WM diets with 0.3 g per week (P < 0.05). CONCLUSION: WS processed with formic acid under conditions of low pH is beneficial for the white shrimp L. vannamei. It sustained reasonable weight gain combined with soybean meal in practical diets. On the other hand, BHT addition was beneficial in preventing oxidative action during silage preparation. Copyright © 2012 Society of Chemical Industry 相似文献
102.
Bernal RA Agrawal R Peng B Bertness KA Sanford NA Davydov AV Espinosa HD 《Nano letters》2011,11(2):548-555
We characterized the elastic properties of GaN nanowires grown along different crystallographic orientations. In situ transmission electron microscopy tensile tests were conducted using a MEMS-based nanoscale testing system. Complementary atomistic simulations were performed using density functional theory and molecular dynamics. Our work establishes that elasticity size dependence is limited to nanowires with diameters smaller than 20 nm. For larger diameters, the elastic modulus converges to the bulk values of 300 GPa for c-axis and 267 GPa for a- and m-axis. 相似文献
103.
104.
Many neurotransmitters, such as γ-amino butyric acid (GABA), can act as chemical cues influencing settlement and metamorphosis
in benthic marine invertebrates. This effect has been described especially in mollusks, such as mussels, clams, or haliotids.
This study describes the first record of the effect of GABA on patellogastropod populations. Special attention was paid to
the effect of the compound on recruitment processes. The experiment was carried out using 10 × 10 cm artificial limestone
plates that were drilled into intertidal rocks at different inclinations, and periodically treated with a 1 mM GABA solution.
A total of five limpet species was considered (four patellid limpet species and the pulmonate Siphonaria pectinata). Each individual recorded on the plates as well as within a 20 × 20 cm quadrant was measured, identified to species level,
and its straight-line distance to the application point was registered. Treated surfaces were the first to possess both adults
and recruits. Individuals also were found in a higher number around GABA-treated plates than around controls. The results
indicated that the compound may not only enhance recruitment, but also might accelerate it. Recruits were located at higher
distances from GABA treated plates than from control surfaces. This supports the hypothesis that this is the life history
stage most sensitive to the compound. The behavior shown by the individuals belonging to the two endangered patellid species
present in the study area (Patella ferruginea and Cymbula nigra) also were analyzed. For the former, the results indicated that the use of GABA may have similar effects on recruitment similar
to the presence of adult conspecifics. This is the first report of the effect of GABA on patellid limpet recruitment and population
dynamics. Conservational implications of the results are discussed. 相似文献
105.
L.S. Cavalcante N.C. Batista T. Badapanda M.G.S. Costa M.S. Li W. Avansi V.R. Mastelaro E. Longo J.W.M. Espinosa M.F.C. Gurgel 《Materials Science in Semiconductor Processing》2013,16(3):1035-1045
Ba(Zr0.75Ti0.25)O3 (BZT-75/25) powders were synthesized by the polymeric precursor method. Samples were structurally characterized by X-ray diffraction (XRD), Rietveld refinement, X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) techniques. Their electronic structures were evaluated by first-principle quantum mechanical calculations based on density functional theory at the B3LYP level. Their optical properties were investigated by ultraviolet-visible (UV-Vis) spectroscopy and photoluminescence (PL) measurements at room temperature. XRD patterns and Rietveld refinement data indicate that the samples have a cubic structure. XANES spectra confirm the presence of pyramidal [TiO5] clusters and octahedral [TiO6] clusters in the disordered BZT-75/25 powders. EXAFS spectra indicate distortion of Ti–O and Ti–O–Ti bonds the first and second coordination shells, respectively. UV-Vis absorption spectra confirm the presence of different optical bandgap values and the band structure indicates an indirect bandgap for this material. The density of states demonstrates that intermediate energy levels occur between the valence band (VB) and the conduction band (CB). These electronic levels are due to the predominance of 4d orbitals of Zr atoms in relation to 3d orbitals of Ti atoms in the CB, while the VB is dominated by 2p orbitals related to O atoms. There was good correlation between the experimental and theoretical optical bandgap values. When excited at 482 nm at room temperature, BZT-75/25 powder treated at 500 °C for 2 h exhibited broad and intense PL emission with a maximum at 578 nm in the yellow region. 相似文献
106.
The phenolic composition and antioxidant activity of musts and skin extracts from Tempranillo grapes dried for variable lengths of times were examined here. Both were found to increase in the grape must with increasing drying time, but the opposite trend was observed in the skin extracts. The antioxidant activity of the must and skin was largely due to anthocyanins. Also, the anthocyanins fraction exhibited the highest antioxidant activity per gram of phenolic compound in the musts and skin extracts at the end of the drying process, polymeric pigments and high-molecular-weight procyanidins were also prominent in this respect. In vivo antioxidant activity in terms of protein oxidation and survival of Saccharomyces cerevisiae cells previously incubated with 10 μg/mL of polyphenols from the musts and skins and exposed to hydrogen peroxide was also measured. Both extracts exerted a protective effect against oxidative stress, the effect increasing with increasing dehydration time and being somewhat higher for skin than for must. Thus, must and skin from dehydrated grapes possess antioxidant properties, which allow the latter, a by-product of sweet wine, to be used as a natural source of antioxidants. 相似文献
107.
108.
Jorge E. Collazos-Castro Ana M. Cruz Mnica Carballo-Vila Mnica Lira-Cantú Llibertat Abad ngel Prez del Pino Jordi Fraxedas Aurlie San Juan Carlos Fonseca Ana P. Pêgo Nieves Casa-Pastor 《Thin solid films》2009,518(1):160-170
Titanium oxides have anti-inflammatory activity and tunable electrochemical properties that make them attractive materials for biomedical applications. This work investigated the compatibility of nanometric coatings of low-temperature phases of TiO2 with neurons in 4-day and 10-day cultures, using different cell densities to quantify cell survival and neurite extension. TiO2 films were prepared by sol–gel and thermal treatment (250–450 °C) of hydrolyzed titanium tetra-isopropoxide on electrically conducting or insulating slides. The conducting substrates were not passivated by the nanometric oxide layer and could be used as electrodes. Characterization of the films showed nano-structured TiO2 containing exclusively Ti+4 valence in anatase and amorphous phases. When coated with polylysine, all films permitted good neuron attachment and survival for at least ten days in culture. However, they generally reduced neurite growth compared to cell culture borosilicate glass, with dendrites more affected than axons. The analyses of surface topography, hydrophilicity, charge and chemical composition revealed that TiO2 chemistry was the main factor responsible for neurite inhibition. 相似文献
109.
Jesús Beltrn-García Juan J. Manclús Eva M. García-Lpez Nieves Carbonell Jos Ferreres María Rodríguez-Gimillo Concepcin Garcs Federico V. Pallard Jos L. García-Gimnez ngel Montoya Carlos Rom-Mateo 《International journal of molecular sciences》2021,22(18)
Sepsis management remains one of the most important challenges in modern clinical practice. Rapid progression from sepsis to septic shock is practically unpredictable, hence the critical need for sepsis biomarkers that can help clinicians in the management of patients to reduce the probability of a fatal outcome. Circulating nucleoproteins released during the inflammatory response to infection, including neutrophil extracellular traps, nucleosomes, and histones, and nuclear proteins like HMGB1, have been proposed as markers of disease progression since they are related to inflammation, oxidative stress, endothelial damage, and impairment of the coagulation response, among other pathological features. The aim of this work was to evaluate the actual potential for decision making/outcome prediction of the most commonly proposed chromatin-related biomarkers (i.e., nucleosomes, citrullinated H3, and HMGB1). To do this, we compared different ELISA measuring methods for quantifying plasma nucleoproteins in a cohort of critically ill patients diagnosed with sepsis or septic shock compared to nonseptic patients admitted to the intensive care unit (ICU), as well as to healthy subjects. Our results show that all studied biomarkers can be used to monitor sepsis progression, although they vary in their effectiveness to separate sepsis and septic shock patients. Our data suggest that HMGB1/citrullinated H3 determination in plasma is potentially the most promising clinical tool for the monitoring and stratification of septic patients. 相似文献
110.
Nieves Sanjuán Gabriela Clemente José Bon Antonio Mulet 《European Food Research and Technology》2001,213(6):474-479
Different blanching treatments were applied to broccoli florets prior to dehydration in order to improve product quality. The pretreatments used were a conventional blanching in water at 99ǃ °C, and a stepwise blanching (a blanching at low temperature followed by a short blanching at high temperature after a holding time) using different temperatures for the first step (50, 55, 60, 65 and 70 °C). Five rehydration temperatures were used (25, 40, 55, 65 and 80 °C). Rehydration rate (Deff and We), chlorophyll content and texture of the rehydrated product were evaluated. Rehydration was modelled according to Fick's diffusion equation. A good agreement between the model and the experimental data was obtained when Deff and We values were identified for each temperature (average explained variance 96.9%). Samples stepwise blanched at 60 °C showed, on the average, the lowest We values. Stepwise blanching at 60-65 °C and rehydration at 25-55 °C were the combinations that gave the firmest product. Stepwise blanching at 50 °C together with the conventional blanching (99ǃ °C) and rehydration between 25 and 65 °C were the combinations that allowed preservation of the highest chlorophyll content. From these results, it seems difficult to obtain firm samples with a high chlorophyll content without additives. 相似文献