Apparent digestibility coefficient of protein and amino acids of acid, biological and enzymatic silage for Nile tilapia (Oreochromis niloticus)

Using the fish silage to partially replace proteic feedstuff in aquafeeds is an alternative to mitigate sanitary and environmental problems caused by the lack of adequate destination for fisheries residues. It would also lower feed costs, consequently improving fish culture profitability. However, using fish silages in aquafeeds depends on determination of its apparent digestibility coefficients (ADC). This work aimed to determining the ADC of crude protein and amino acids of acid silage (AS), biological silage (BS) and enzymatic silage (ES) for juvenile Nile tilapia (94.5 +/- 12.7 g). The ADC(CP) was: 92.0%, 89.1% and 93.7% for AS, BS and SE respectively. The average ADC of amino acids was: 91.8%, 90.8% and 94.6% for AS, BS and ES respectively. Results encourage the use of AS, BS and ES to partially replace protein sources in balanced diets for neotropical fish.

NMR imaging of fluid pathways during drainage of softwood in a pressure membrane chamber

An experiment was implemented to study fluid flow in a pressure media. This procedure successfully combines nuclear magnetic resonance imaging with a pressure membrane chamber in order to visualize the non-wetting and wetting fluid flows with controlled boundary conditions. A specially designed pressure membrane chamber, made of non-magnetic materials and able to withstand 4 MPa, was designed and built for this purpose. These two techniques were applied to the drainage of Douglas fir sapwood. In the study of the longitudinal flow, narrow drainage fingers are formed in the latewood zones. They follow the longitudinal direction of wood and spread throughout the sample length. These fingers then enlarge in the cross-section plane and coalesce until drainage reaches the whole latewood part. At the end of the experiments, when the drainage of liquid water in latewood is completed, just a few sites of percolation appear in earlywood zones. This difference is a result of the wood anatomical structure, where pits, the apertures that allow the sap to flow between wood cells, are more easily aspirated in earlywood than in latewood. (C) 2007 Elsevier Ltd. All rights reserved.

Quorum sensing detected by atomic force microscopy imaging of corrals surrounding multicellular arrangement of bacteria

Connectivity of the glycocalyx covering of small communities of Acidithiobacillus ferrooxidans bacteria deposited on hydrophilic mica plates was imaged by atomic force microscopy. When part of the coverage was removed by water rinsing, an insoluble structure formed by corrals surrounding each individual bacterium was observed. A collective ring structure with clustered bacteria (>= 3) was observed, which indicates that the bacteria perceived the neighborhood in order to grow a protective structure that results in smaller production of exopolysaccharides material. The most surprising aspect of these collective corral structures was that they occur at a low bacterial cell density. The deposited layers were also analyzed by confocal Raman microscopy and shown to contain polysaccharides, protein, and glucoronic acid.

A new deuterogynous eriophyid mite (Acari : Eriophyidae) with dimorphic males from Caesalpinia echinata (Caesalpiniaceae) from Brazil: Description and biological observations

Aceria inusitata Britto and Navia n. sp. (Acari: Eriophyidae) is described from protogynes, deutogynes and two forms of males occurring under a ""patches of webbing"" from ""pau-brasil,"" Caesalpinia echinata L. (Caesalpiniaceae), leaves. This is the first example of a deuterogynous eriophyid mite in tropical regions with two forms of males, one resembling the protogyne and the other the deutogyne. In addition, biological observations are presented. Aberoptus cerostructor Flechtmann, is given a new generic assignment, Aceria cerostructor n. comb.

(1)H NMR determination of beta-N-methylamino-L-alanine (L-BMAA) in environmental and biological samples

A nuclear magnetic resonance ((1)H NMR) method for the determination of beta-N-methylamino-L-alanine (L-BMAA) in environmental aqueous samples was developed and validated. L-BMAA is a neurotoxic modified amino acid that can be produced by cyanobacteria in aqueous environments. This toxin was extracted from samples by means of solid-phase extraction (SPE) and identified and quantified by (1)H NMR without further derivatization steps. The lower limit of quantification (LLOQ) was 5 mu g/mL Good inter and intra-assay precision was also observed (relative standard deviation <8.5%) with the use of 4-nitro-DL-phenylalanine as an internal standard (IS). This method of 1H NMR analysis is not time consuming and can be readily utilized to monitor L-BMAA and confirm its presence in environmental and biological samples. (C) 2008 Elsevier Ltd. All rights reserved.

Novel deoxy-selenylconduritols: chemoenzymatic synthesis and biological evaluation

The first synthesis of two selenyldeoxycyclitols (4-bromo-2-phenylselenyl conduritol F and 6-phenylselenylconduritol F) is reported via a chemoenzymatic enantioselective route. The key step of the synthesis is the selenolysis of a vinyl epoxide. The new compounds were evaluated for their capacity to inhibit the growth of different microorganisms using a modification of the agar diffusion technique with thin layer chromatography plates as support. (C) 2009 Elsevier Ltd. All rights reserved.

Influence of Pluronic (R) F68 on Ceftazidime Biological Activity in Parenteral Solutions

beta-Lactam antimicrobials are known to have a low concentration/therapeutic response. However, extending the period in which beta-lactam are free in the plasma does directly influence therapeutic outcomes. The objective of this study was to evaluate the influence of Pluronic (R) F68 on the antimicrobial activity of ceftazidime when admixed with aminophylline in parenteral solutions by the evaluation of its minimal inhibitory concentration (MIC) within 24 h. Ceftazidime, aminophylline, and Pluronics (R) F68 were evaluated using the MIC method against Escherichia coli and Pseudomonas aeruginosa, with these compounds individually and associated in the same parenteral solutions. When Pluronics (R) F68 was admixtured with ceftazidime alone or with ceftazidime and aminophylline, it was possible to observe lower MIC values not only at 24 h but also at 0 h for both microorganisms. This indicates that Pluronics (R) F68 may be able to enhance ceftazidime antimicrobial activity in the presence or absence of aminophylline. This fact suggests that Pluronics (R) F68 can be applied to allow the administration of ceftazidime under continuous infusion in parenteral solutions, beneficiating hospital pharmacotherapy. It may also be possible to reduce ceftazidime doses in formulations achieving the same therapeutic results. (C) 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:715-720, 2011

Biogas production and valorization by means of a two-step biological process

The scope of this research work was to investigate biogas production and purification by a two-step bench-scale biological system, consisting of fed-batch pulse-feeding anaerobic digestion of mixed sludge, followed by methane enrichment of biogas by the use of the cyanobacterium Arthrospira platensis. The composition of biogas was nearly constant, and methane and carbon dioxide percentages ranged between 70.5-76.0% and 13.2-19.5%, respectively. Biogas yield reached a maximum value (about 0.4 m(biogas)(3)/kgCOD(i)) at 50 days-retention time and then gradually decreased with a decrease in the retention time. Biogas CO(2) was then used as a carbon source for A. platensis cultivation either under batch or fed-batch conditions. The mean cell productivity of fed-batch cultivation was about 15% higher than that observed during the last batch phase (0.035 +/- 0.006 g(DM)/L/d), likely due to the occurrence of some shading effect under batch growth conditions. The data of carbon dioxide removal from biogas revealed the existence of a linear relationship between the rates of A. platensis growth and carbon dioxide removal from biogas and allowed calculating carbon utilization efficiency for biomass production of almost 95%. (C) 2009 Elsevier Ltd. All rights reserved.

Novel benzofuroxan derivatives against multidrug-resistant Staphylococcus aureus strains: Design using Topliss` decision tree, synthesis and biological assay

The aim of this study was the design of a set of benzofuroxan derivatives as antimicrobial agents exploring the physicochemical properties of the related substituents. Topliss` decision tree approach was applied to select the substituent groups. Hierarchical cluster analysis was also performed to emphasize natural clusters and patterns. The compounds were obtained using two synthetic approaches for reducing the synthetic steps as well as improving the yield. The minimal inhibitory concentration method was employed to evaluate the activity against multidrug-resistant Staphylococcus aureus strains. The most active compound was 4-nitro-3-(trifluoromethyl)[N`-(benzofuroxan-5-yl) methylene] benzhydrazide (MIC range 12.7-11.4 mu g/mL), pointing out that the antimicrobial activity was indeed influenced by the hydrophobic and electron-withdrawing property of the substituent groups 3-CF(3) and 4-NO(2), respectively. (C) 2011 Elsevier Ltd. All rights reserved.

Evaluation of Some Biological Aspects of the Presence of Abrasive Silica and Thickening Silica in Basic Formulations of Dentifrices

The aim of this study was to evaluate some biological characteristics and toxicity of basic formulations of dentifrices containing such substances, and to compare them with two existing products in market which also contains silic in their formulations. In this way, it was evaluated some biological parameters: weight of the animals, oral toxicity, hematological parameters, urinary analysis, and histological evaluation. The thrombocytes were also statistically at normal levels. The glutamate-pyruvate transaminase (TGP) showed normal aspect in 5 of the tested groups, as in control. Meanwhile, the oxalacetic transaminase (AST) in one group had a small increase in the control group. Regarding urine, in exception the rats of one group, the rats of the 4 other experimental groups showed leukocytosis urinary statistically higher than the control group. The histological evaluation of the animals showed that specimens from liver, stomach, kidney and submandibular gland presented normal aspects for these organs, without significant characteristics related to inflammatory infiltrates in any of the 6 samples tested in their respective groups.

Random numbers from astronomical imaging

This article describes a method to turn astronomical imaging into a random number generator by using the positions of incident cosmic rays and hot pixels to generate bit streams. We subject the resultant bit streams to a battery of standard benchmark statistical tests for randomness and show that these bit streams are statistically the same as a perfect random bit stream. Strategies for improving and building upon this method are outlined.

Prefrontal cortex involvement in selective letter generation: A functional magnetic resonance imaging study

Cerebral responses to alternating periods of a control task and a selective letter generation paradigm were investigated with functional Magnetic Resonance Imaging (fMRI). Subjects selectively generated letters from four designated sets of six letters from the English language alphabet, with the instruction that they were not to produce letters in alphabetical order either forward or backward, repeat or alternate letters. Performance during this condition was compared with that of a control condition in which subjects recited the same letters in alphabetical order. Analyses revealed significant and extensive foci of activation in a number of cerebral regions including mid-dorsolateral frontal cortex, inferior frontal gyrus, precuneus, supramarginal gyrus, and cerebellum during the selective letter generation condition. These findings are discussed with respect to recent positron emission tomography (PET) and fMRI studies of verbal working memory and encoding/retrieval in episodic memory.

Morphological and biological notes on Polymorphus (Profilicollis) sphaerocephalus and Corynosoma stanleyi (Polymorphidae : Acanthocephala)

Polymorphus (Profilicollis) sphaerocephalus (Bremser in Rudolphi, 1819) Van Cleave, 1947 (Polymorphidae) cystacanths were recovered from 5 species of grapsid crabs (Paragrapsus gaimardii (Milne Edwards, 1837), Paragrapsus laevis (Dana, 1852), Paragrapsus quadridentatus (Milne Edwards, 1837), Brachynotus spinosus (Milne Edwards, 1853), and Cyclograpsus granulosus (Milne Edwards, 1853)) and 1 species of portunid crab (Nectocarcinus integrifrons (Linnaeus, 1766)) from intertidal zones in southern temperate waters of Australia. Cystacanths of Corynosoma stanleyi Smales, 1986 (Polymorphidae) were also recovered from P. gaimardii, P. quadridentatus, and C. granulosus. Polymorphus (P.) sphaerocephalus was the most prevalent (100%) in C. granulosus at Flinders I. and C. stanleyi was most prevalent (59.1%) in C. granulosus at Dunally Channel, Tasmania.