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991.
Albert Westergren Christine Wann-Hansson Elisabet Bergh Börgdal Jeanette Sjölander Rosmarie Strömblad Rosemarie Klevsgård Carolina Axelsson Christina Lindholm Kerstin Ulander 《Nutrition journal》2009,8(1):20-8
Background
To explore the point prevalence of the risk of malnutrition and the targeting of nutritional interventions in relation to undernutrition risk and hospital volume. 相似文献992.
Hydrodesulfurization (HDS) of dibenzothiophene (DBT) was carried out in a batch reactor at 3.3 MPa and 340 °C. Sulfided catalysts showed a wide range of activity variation as a function of support composition, which established that sulfided active phases strongly depend on the nature and composition of support. The incorporation of MgO, SiO2, TiO2 and ZrO2 with γ-Al2O3 alters the nature of active phase interactions on the support surface. Therefore, these oxides play a structural promoting role to the support contribution and its interaction towards the active metal geometry. Different preparation methods of catalysts were carried out by using different additives during the impregnation. It is demonstrated that co-impregnation method found better activity than sequential impregnation. The urea additive prepared catalyst provides promising activity compared with other chelating agents. An Al2O3-B2O3 mixed oxide supported catalyst was tested at high pressure with real feed (Maya heavy oil diluted with hydrodesulfurized diesel). The mixed oxide supported catalyst showed rapid deactivation with time-on-stream than the alumina supported catalyst that may be due to an enhancement in acidic sites. The activity results demonstrated that the number of catalytic sites is a combination of support composition, additive, impregnation pH, drying and calcinations of catalysts. 相似文献
993.
Francisco MonteroSilva Marcelo J. Kogan Ivn Montenegro Fanny Guzmn Soledad Navarrete Carolina Parra Michael Seeger 《IET nanobiotechnology / IET》2019,13(3):320
This work determined the potency of hexyl‐ciprofloxacin molecules that reversibly interact with gold nanoparticles (AuNPs) passivated with 11‐mercaptoundecanoic acid (MUA) on Escherichia coli cells. For this, partition of modified antibiotic between different compartments of the gold colloid was determined using analytical techniques. First, concentration of hexyl‐ciprofloxacin was determined in the continuous phase of the colloid. Subsequently, the colloid was exposed to a volume of organic immiscible solvent and concentration of the transferred molecules was determined in the organic phase. Comparison of the amount of hexyl‐ciprofloxacin in each phase revealed that interaction between molecules and nanoparticles was reversible. Later, this work determined the potency of a population of hexyl‐ciprofloxacin molecules contained in a volume of the colloid, and the potency of other population of molecules that only interact with the continuous phase of the colloid. The absolute difference between these two values was proportional to the potency of a number of molecules that interact with the nanoparticles of the colloid.Inspec keywords: organic compounds, nanoparticles, gold, colloids, microorganisms, molecular biophysics, drug delivery systems, nanomedicineOther keywords: continuous phase, hexyl‐ciprofloxacin molecules, gold nanoparticles, gold colloid, 11‐mercaptoundecanoic acid, Escherichia coli cells, modified antibiotics, RP‐HPLC, organic immiscible solvent, reversible interaction, Au 相似文献
994.
Carolina Cruz Viggi Francesca Pagnanelli Luigi Toro 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):859-863
BACKGROUND: In this study a comparison between two continuously operating fixed‐bed column systems was performed in order to select the best operating conditions in terms of organic sources for sulphate reducing bacteria (SRB). The first column system (solid substrate, SS) was filled with a solid reactive mixture containing the organic matter necessary for SRB growth, while the second one (liquid substrate, LS) was filled with inert material and continuously fed by ethanol. RESULTS: In the SS column 50 ± 10% sulphate abatement was reached at steady state, while metals were totally removed. Blank tests showed that biosorption was mainly responsible for both sulphate and metal removal. In the LS column, sulphate abatement was 70 ± 10% at steady state against 10 ± 5% of an identical column without inoculum (blank liquid substrate, BLS). Comparison with BLS showed that the main mechanism operating in this system was bioprecipitation. Estimated degradation rate constants for both SS and LS columns indicate similar performances (0.008 ± 0.001 and 0.0085 ± 0.0005 d?1 for SS and LS, respectively). CONCLUSIONS: LS column systems offer a valid alternative to conventional SS systems, avoiding the use of potentially harmful wastes as organic sources for SRB metabolism. Copyright © 2009 Society of Chemical Industry 相似文献
995.
F. Javier Benitez Juan L. Acero Francisco J. Real Carolina Garcia 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(12):1883-1893
BACKGROUND: Phenyl‐urea herbicides are found in surface waters and wastewaters as a consequence of their extensive use in agriculture. Due to their pollutant power, the removal of phenyl‐ureas is a priority objective in water treatment technologies. RESULTS: Four selected phenyl‐ureas herbicides (linuron, diuron, chlortoluron and isoproturon), dissolved in two water matrices (a groundwater and and a reservoir water), were subjected to sequential combinations of chemical treatments and membrane filtration processes. Two specific sequences were conducted: first, a chemical oxidation stage (where UV radiation, ozone and ozone plus hydrogen peroxide were used) followed by a nanofiltration process; and second, a membrane filtration stage (using UF and NF membranes) followed by an ozonation stage. Values for the herbicide removals in the oxidation stages and for the rejection coefficients in the filtration stages are provided, and the partial contribution of the different stages is established for each combined treatment. CONCLUSIONS: High removals (over 80%) were reached for phenyl‐ureas elimination by most of the combined processes tested. In the combined chemical oxidation/nanofiltration processes, the most effective was an ozonation pretreatment ([O3]0 = 1.5 mg L?1)) followed by a NF step. In the opposite sequence filtration/chemical oxidation, the most effective was a NF pretreatment followed by the ozonation ([O3]0 = 2 mg L?1). Copyright © 2009 Society of Chemical Industry 相似文献
996.
997.
Maria Carolina S. Marquezin Darlle S. Araujo Juliana N. Amato Taís de S. Barbosa Fernando L. A. Fonseca Maria B. D. Gavio Paula Midori Castelo 《Journal of texture studies》2019,50(3):248-256
As sucking habits and eating behavior may be interrelated and also associated with taste, body composition, and sociodemographic factors, the objective was to perform an exploratory analysis to identify groups of children with a high degree of association between intragroup subjects, providing explanation and interpretation of the data. The study initially included 352 prepubertal children (197 girls; 7‐ to 11‐year‐old), from whom information about sociodemographic characteristics, duration of breastfeeding, past bottle‐feeding and non‐nutritive sucking habits, taste sensitivity, body mass index (BMI), and consistency of food ingested were collected. Salivary concentrations of amylase and total protein were also determined. Data were submitted to cluster analysis (hierarchical analysis, K‐means, and silhouette plot), one‐way ANOVA and correlation tests. Cluster analysis included 159 children, generating three reliable and meaningful clusters: Cluster 1 (labeled “good tasters”), was characterized by older children and higher taste sensitivity; Cluster 2 (“softer food consistency”) by longer bottle‐feeding duration and children who eat food with lower consistency, and Cluster 3 (“breastfed”) by longer breastfeeding duration (silhouette coefficient = 0.61). Cluster 3 also showed the higher percentage of normal‐weight children, normal delivery, maternal schooling, and lower rate of past non‐nutritional sucking habit. No correlation was found between salivary amylase and total protein concentrations, taste sensitivity and BMI, although taste sensitivity showed to be higher among girls (p = 0.002; power = 88%). The study identified three clusters, highlighting the relationship between nutritional sucking habits, consistency of food ingested, and sociodemographic characteristics. Most importantly, a close relation between bottle‐feeding and consumption of soft food consistency was observed. 相似文献
998.
María Carolina Talio Marta O. Luconi Adriana N. Masi Liliana P. Fernndez 《Journal of hazardous materials》2009,170(1):272-277
A highly sensitive micelle-mediated extraction methodology for the preconcentration and determination of trace levels of cadmium by molecular fluorescence has been developed. Metal was complexed with o-phenanthroline (o-phen) and eosin (eo) at pH 7.6 in buffer Tris medium and quantitatively extracted into a small volume of surfactant-rich phase of PONPE 7.5 after centrifugating. The chemical variables affecting cloud point extraction (CPE) were evaluated and optimized. The RSD for six replicates of cadmium determinations at 0.84 μg L−1 level was 1.17%. The linearity range using the preconcentration system was between 2.79 × 10−3 μg L−1 and 2.81 μg L−1 with a correlation coefficient of 0.99. Under the optimal conditions, it obtained a LOD of 8.38 × 10−4 μg L−1 and LOQ of 2.79 × 10−3 μg L−1. The method presented good sensitivity and selectivity and was applied to the determination of trace amounts of cadmium in commercially bottled mineral water, tap water and water well samples with satisfactory results. The proposed method is an innovative application of CPE-luminescence to metal analysis comparable in sensitivity and accuracy with atomic spectroscopies. 相似文献
999.
A system for visual surveys of bottom fishes, assembled from readily available components, is described. A camera and a depth sounder transducer are mounted on a towed body. The camera captures the images, and the depth sounder measures the distance between the camera and the bottom. A video recorder is used to record the data—the video channel for the image, and the audio channel for distance information, which is dictated from the depth sounder display into a microphone. A relationship between distance and magnification is used to estimate the width of the survey path and the size of surveyed objects. A comparison of round goby (Apollonia melanostoma) density estimated by repeated seining and use of the underwater visual apparatus showed that the smallest individuals are underrepresented by the visual assessment, but the visual method detects about 85% of the 50 mm TL or larger gobies. 相似文献
1000.
Bonache MA García-Martínez C García de Diego L Carreño C Pérez de Vega MJ García-López MT Ferrer-Montiel A González-Muñiz R 《ChemMedChem》2006,1(4):429-438
The transient receptor potential vanilloid member 1 (TRPV1), an integrator of multiple pain-producing stimuli, is regarded nowadays as an important biological target for the discovery of novel analgesics. Here, we describe the first experimental evidence for the behavior of an old family of analgesic dipeptides, namely Xaa-Trp(Nps) and Trp(Nps)-Xaa (Xaa=Lys, Arg) derivatives, as potent TRPV1 channel blockers. We also report the synthesis and biological investigation of a series of new conformationally restricted Trp(Nps)-dipeptide derivatives with improved TRPV1/NMDA selectivity. Compound 15 b, which incorporates an N-terminal 2S-azetidine-derived Arg residue, was the most selective compound in this series. Collectively, a new family of TRPV1 channel blockers emerged from our results, although further modifications are required to fine-tune the potency/selectivity/toxicity balance. 相似文献