Effect of processing on amine formation and the lipid profile of cod (Gadus morhua) roe

The processing of fish roe leads to changes in its chemical composition, the extent of which depends on the techniques and additives employed. This study aimed to investigate the effects of ripening temperature and the use of sodium benzoate and citric acid on the quality of ripened cod roe, with respect to the contents of volatile base nitrogen (VBN), trimethylamine (TMA), biogenic amines (BA) and on the lipid composition. In comparison with fresh roes, ripened roes presented higher contents of VBN, TMA, BA and the proportion of free fatty acids regardless of the temperature and additives used during the ripening process. The greatest increases were observed in the samples ripened at 17 degrees C without additives, in which histamine was detected at 8.8 mg/100 g. A low ripening temperature was the main factor responsible for minimising changes in the cod roe composition. The addition of sodium benzoate as a preservative or citric acid to decrease the pH value had a significant effect in maintaining the quality of the cod roes, mainly at high ripening temperature. (C) 2011 Elsevier Ltd. All rights reserved.

Increase of Cholesterol Oxidation and Decrease of PUFA as a Result of Thermal Processing and Storage in Eggs Enriched with n-3 Fatty Acids

In this work, cholesterol oxide formation and alteration of fatty acid composition were analyzed in n-3 enriched eggs under different storage periods and two temperatures. The eggs enriched with n-3 fatty acids were stored at 5 or 25 degrees C for 45 days and subsequently boiled or fried. For each treatment, 12 yolks were analyzed every 15 days including time zero. The concentrations of the cholesterol oxides 7-ketocholesterol, 7 beta-hydroxycholesterol, and 7 alpha-hydroxycholesterol increased during the storage period and were higher in fried eggs. Only the 7-ketocholesterol was affected by the storage temperature, and its concentration was highest in eggs stored at 25 degrees C. There was no significant difference in the contents of cholesterol and vitamin E at the different storage periods; however, the concentration of vitamin E decreased with thermal treatment. In addition, the n-3 polyunsaturated fatty acids, especially 18:3, 20:5, and 22:6, were reduced throughout the storage at 5 and 25 degrees C.

Nop53p interacts with 5.8S rRNA co-transcriptionally, and regulates processing of pre-rRNA by the exosome

In eukaryotes, pre-rRNA processing depends on a large number of nonribosomal trans-acting factors that form intriguingly organized complexes. One of the early stages of pre-rRNA processing includes formation of the two intermediate complexes pre-40S and pre-60S, which then form the mature ribosome subunits. Each of these complexes contains specific pre-rRNAs, ribosomal proteins and processing factors. The yeast nucleolar protein Nop53p has previously been identified in the pre-60S complex and shown to affect pre-rRNA processing by directly binding to 5.8S rRNA, and to interact with Nop17p and Nip7p, which are also involved in this process. Here we show that Nop53p binds 5.8S rRNA co-transcriptionally through its N-terminal region, and that this protein portion can also partially complement growth of the conditional mutant strain Delta nop53/GAL:NOP53. Nop53p interacts with Rrp6p and activates the exosome in vitro. These results indicate that Nop53p may recruit the exosome to 7S pre-rRNA for processing. Consistent with this observation and similar to the observed in exosome mutants, depletion of Nop53p leads to accumulation of polyadenylated pre-rRNAs.

Transcriptional Processing of the pst Operon of Escherichia coli

The pst operon of Escherichia coli is composed of five genes that encode a high-affinity phosphate transport system. pst belongs to the PHO regulon, which is a group of genes and operons that are induced in response to phosphate limitation. The pst operon also has a regulatory role in the repression of PHO genes` transcription under phosphate excess conditions. Transcription of pst is initiated at the promoter located upstream to the first gene, pstS. Immediately after its synthesis, the primary transcript of pst is cleaved into shorter mRNA molecules in a ribonuclease E-dependent manner. Other ribonucleases, such as RNase III and MazF, do not play a role in pst mRNA processing. RNase E is thus at least partially responsible for processing the pst primary transcript.

Modulation of Bone Morphogenetic Protein-9 Expression and Processing by Insulin, Glucose, and Glucocorticoids: Possible Candidate for Hepatic Insulin-Sensitizing Substance

Bone morphogenetic protein 9 (BMP-9), a member of the TGF-beta superfamily predominantly expressed in nonparenchymal liver cells, has been demonstrated to improve glucose homeostasis in diabetic mice. Along with this therapeutic effect, BMP-9 was proposed as a candidate for the hepatic insulin-sensitizing substance ( HISS). Whether BMP-9 plays a physiological role in glucose homeostasis is still unknown. In the present study, we show that BMP-9 expression and processing is severely reduced in the liver of insulin-resistant rats. BMP-9 expression and processing was directly stimulated by in situ exposition of the liver to the combination of glucose and insulin and oral glucose in overnight fasted rats. Additionally, prolonged fasting ( 72 h) abrogated refeeding-induced BMP-9 expression and processing. Previous exposition to dexamethasone, a known inductor of insulin resistance, reduced BMP-9 processing stimulated by the combination of insulin and glucose. Finally, we show that neutralization of BMP-9 with an anti-BMP-9 antibody induces glucose intolerance and insulin resistance in 12-h fasted rats. Collectively, the present results demonstrate that BMP-9 plays an important role in the control of glucose homeostasis of the normal rat. Additionally, BMP-9 is expressed and processed in an HISS-like fashion, which is impaired in the presence of insulin resistance. BMP-9 regulation according to the feeding status and the presence of diabetogenic factors reinforces the hypothesis that BMP-9 might exert the role of HISS in glucose homeostasis physiology. ( Endocrinology 149: 6326-6335, 2008)

Mixed multiplicities and the minimal number of generator of modules

Let (R, m) be a d-dimensional Noetherian local ring. In this work we prove that the mixed Buchsbaum-Rim multiplicity for a finite family of R-submodules of R(p) of finite colength coincides with the Buchsbaum-Rim multiplicity of the module generated by a suitable superficial sequence, that is, we generalize for modules the well-known Risler-Teissier theorem. As a consequence, we give a new proof of a generalization for modules of the fundamental Rees` mixed Multiplicity theorem, which was first proved by Kirby and Rees in (1994, [8]). We use the above result to give an upper bound for the minimal number of generators of a finite colength R-submodule of R(p) in terms of mixed multiplicities for modules, which generalize a similar bound obtained by Cruz and Verma in (2000, [5]) for m-primary ideals. (C) 2009 Elsevier B.V. All rights reserved.

A new proposal for the picture changing operators in the minimal pure spinor formalism

Using a new proposal for the ""picture lowering"" operators, we compute the tree level scattering amplitude in the minimal pure spinor formalism by performing the integration over the pure spinor space as a multidimensional Cauchy-type integral. The amplitude will be written in terms of the projective pure spinor variables, which turns out to be useful to relate rigorously the minimal and non-minimal versions of the pure spinor formalism. The natural language for relating these formalisms is the. Cech-Dolbeault isomorphism. Moreover, the Dolbeault cocycle corresponding to the tree-level scattering amplitude must be evaluated in SO(10)/SU(5) instead of the whole pure spinor space, which means that the origin is removed from this space. Also, the. Cech-Dolbeault language plays a key role for proving the invariance of the scattering amplitude under BRST, Lorentz and supersymmetry transformations, as well as the decoupling of unphysical states. We also relate the Green`s function for the massless scalar field in ten dimensions to the tree-level scattering amplitude and comment about the scattering amplitude at higher orders. In contrast with the traditional picture lowering operators, with our new proposal the tree level scattering amplitude is independent of the constant spinors introduced to define them and the BRST exact terms decouple without integrating over these constant spinors.

A new processing method of CaZn(2)(OH)(6)center dot 2H(2)O powders: Photoluminescence and growth mechanism

In this communication, we report on the formation of calcium hexahydroxodizincate dehydrate, CaZn(2)(OH)(6)center dot 2H(2)O (CZO) powders under microwave-hydrothermal (MH) conditions. These powders were analyzed by X-ray diffraction (XRD), Field-emission gum scanning electron microscopy (FEG-SEM), ultraviolet-visible (UV-vis) absorption spectroscopy and photoluminescence (PL) measurements. XRD patterns confirmed that the pure CZO phase was obtained after MH processing performed at 130 degrees C for 2 h. FEG-SEM micrographs indicated that the morphological modifications as well as the growth of CZO microparticles are governed by Ostwald-ripening and coalescence mechanisms. UV-vis spectra showed that this material have an indirect optical band gap. The pure CZO powders exhibited an yellow PL emission when excited by 350 nm wavelength at room temperature. (C) 2009 Elsevier Masson SAS. All rights reserved.

Processing of electroactive nanostructured films incorporating carbon nanotubes and phthalocyanines for sensing

The use of carbon nanotubes (CNTs) combined with other materials in nanostructured films has demonstrated their versatility in tailoring specific properties. In this study, we produced layer-by-layer (LbL) films of polyamidoamine-PAMAM-incorporating multiwalled carbon nanotubes (PAMAM-NT) alternated with nickel tetrasulfonated metallophthalocyanine (NiTsPc), in which the incorporation of CNTs enhanced the NiTsPc redox process and its electrocatalytic properties for detecting dopamine. Film growth was monitored by UV-vis spectroscopy, which pointed to an exponential growth of the multilayers, whose roughness increased with the number of bilayers according to atomic force microscopy (AFM) analysis. Strong interactions between -NH3+ terminal groups from PAMAM and -SO3- from NiTsPc were observed via infrared spectroscopy, while the micro-Raman spectra confirmed the adsorption of carbon nanotubes (CNTs) onto the LbL film containing NiTsPc. Cyclic voltammograms presented well-defined electroactivity with a redox pair at 0.86 and 0.87 V, reversibility, a charge-transfer controlled process, and high stability up to 100 cycles. The films were employed successfully in dopamine (DA) detection, with limits of detection and quantification of 10(-7) and 10(-6) mol L-1, respectively. Furthermore, films containing immobilized CNTs could distinguish between DA and its natural interferent, ascorbic acid (AA).

Investigation of AISI 1040 steel corrosion H(2)S solution containing chloride ions by digital image processing coupled with in electrochemical techniques

This paper presents a study of AISI 1040 steel corrosion in aqueous electrolyte of acetic acid buffer containing 3.1 and 31 x 10(-3) mol dm(-3) of Na(2)S in both the presence and absence of 3.5 wt.% NaCl. This investigation of steel corrosion was carried out using potential polarization, and open-circuit and in situ optical microscopy. The morphological analysis and classification of types of surface corrosion damage by digital image processing reveals grain boundary corrosion and shows a non-uniform sulfide film growth, which occurs preferentially over pearlitic grains through successive formation and dissolution of the film. (C) 2011 Elsevier Ltd. All rights reserved.

EFFECTIVE NETWORKS FOR REAL-TIME DISTRIBUTED PROCESSING

This paper applies the concepts and methods of complex networks to the development of models and simulations of master-slave distributed real-time systems by introducing an upper bound in the allowable delivery time of the packets with computation results. Two representative interconnection models are taken into account: Uniformly random and scale free (Barabasi-Albert), including the presence of background traffic of packets. The obtained results include the identification of the uniformly random interconnectivity scheme as being largely more efficient than the scale-free counterpart. Also, increased latency tolerance of the application provides no help under congestion.

Normalization procedure for relaxation studies in NMR quantum information processing

NMR quantum information processing studies rely on the reconstruction of the density matrix representing the so-called pseudo-pure states (PPS). An initially pure part of a PPS state undergoes unitary and non-unitary (relaxation) transformations during a computation process, causing a ""loss of purity"" until the equilibrium is reached. Besides, upon relaxation, the nuclear polarization varies in time, a fact which must be taken into account when comparing density matrices at different instants. Attempting to use time-fixed normalization procedures when relaxation is present, leads to various anomalies on matrices populations. On this paper we propose a method which takes into account the time-dependence of the normalization factor. From a generic form for the deviation density matrix an expression for the relaxing initial pure state is deduced. The method is exemplified with an experiment of relaxation of the concurrence of a pseudo-entangled state, which exhibits the phenomenon of sudden death, and the relaxation of the Wigner function of a pseudo-cat state.

Mineralogical and microthermometric studies and structural aspects of imperial topaz mineralization in Antonio Pereira, Ouro Preto District (Minas Gerais) - Brazil

The occurrences of imperial topaz in the Antonio Pereira mine, Ouro Preto, Minas Gerais, are associated with the metamorphic carbonate rocks of the Minas Supergroup. The crystals have densities varying from 3.46 to 3.58. The parameters of the unitary cells obtained were: 4.658 to 4.663 angstrom (ao), 8.823 to 8.832 angstrom (b(o)), 8.382 to 8.389 angstrom (c(o)), and 344.65 to 345.46 angstrom 3 (V). The refraction indices presented the following variations: 1.622 to 1.630 (nX), 1.624 to 1.632 (nY), 1.633 to 1.640 (nZ), and 0.008 to 0.011 (B). These properties are coherent with the low fluorine contents obtained (16,48%/17,05wt%). Infrared spectroscopy and microthermometry showed that the fluid inclusions, which represent the mineralizing fluids, are formed by H(2)O (with Ca(2+), Mg(2+) and Na(+)), and CO(2) +/- CH(4). The minimal trapping T-P conditions of 290/320 degrees C and 2,349/2,497bar were obtained for the primary fluid inclusions. The pseudo-secondary fluid inclusions were trapped at conditions of lower temperatures and variable pressures, during the deformation process under local alternating states of stress. The microthermometric studies, the structural analysis and the fluorine contents suggest that the mineralized veins were formed from hydrothermal fluids originated during the Brasiliano tectono-metamorphic event.

Structured minimal-memory inexact quasi-Newton method and secant preconditioners for augmented Lagrangian optimization

Augmented Lagrangian methods for large-scale optimization usually require efficient algorithms for minimization with box constraints. On the other hand, active-set box-constraint methods employ unconstrained optimization algorithms for minimization inside the faces of the box. Several approaches may be employed for computing internal search directions in the large-scale case. In this paper a minimal-memory quasi-Newton approach with secant preconditioners is proposed, taking into account the structure of Augmented Lagrangians that come from the popular Powell-Hestenes-Rockafellar scheme. A combined algorithm, that uses the quasi-Newton formula or a truncated-Newton procedure, depending on the presence of active constraints in the penalty-Lagrangian function, is also suggested. Numerical experiments using the Cute collection are presented.