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Pisco grape pomace:Iron/copper speciation and antioxidant properties,towards their comprehensive utilization

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Food Bioscience 2022年第3期47卷 1213-1221页

作者： Fátima Rodríguez-Ramos Raúl cañas-Sarazúa Vilbett Briones-labarca Departamento de Ingeniería en Alimentos Universidad de La SerenaAv.Raúl Bitrán Nachary 1305Box 5991720010La SerenaChile

The pisco and wine industry produces hundreds of tons of grape pomace each year in Chile,generating environmental problems,and demanding urgent strategies for its *** aim of this work was to study the pisco grape pomace based on a physicochemical characterization,an iron/copper speciation analysis,and the optimization for polyphenols recovery,establishing the polyphenolic profile,antioxidant properties,and the Fe^(2+)/Cu^(2+) chelating activity,to promote their revalorization as an ingredient with potential application in the food *** chemical characterization showed mainly high values for crude protein(15.36%dw)and potassium(9240.66 mg/kg).The Fe/Cu speciation depicted that iron and copper soluble forms in pisco pomace flour represented 70.57%and 52.18%,respectively,regarding total *** optimized extract showed mainly pyrogallol,catechin and epicatechin,with concentrations of 1078.43±60.14μg/g,883.20±7.57μg/g and,751.76±23.04μg/g,respectively,with a relevant antioxidant capacity by Oxygen Radical Absorbance capacity(ORAC)of 1402.15μmol TE/g dw GPE and,a better chelating ability to complex Fe^(2+) than Cu^(2+).The pisco pomace was for the first time chemically characterize,showing it as a potential source of minerals and antioxidant biocompounds,making it a good candidate for nutritional applications,as a rich source of organic matter or even could be potentially utilized to produce value-added commodities,toward a circular economy.

关键词： Pisco grape pomace Polyphenols Chemical speciation analysis Antioxidant capacity Metal chelating ability

Structure and Deformation of Intermetallic Beryllides

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Journal of Materials Science & Technology 1994年第6期10卷 391-405页

作者： TG.Nieh(lawrence livermore National laboratory, P.O.Box 808, l-350, livermore, ca 94551, usA ) lawrence livermore Natl lab Livermore United States

Intermetallic beryllides are potential light-weight, high-temperature structural materials. In this paper. the processing techniques, microstructure. deformation, and oxidation properties of intermetallic beryllides are described. In addition to nickel beryllides (NiBe). which is treated as a model *** high beryllium-containing refractory beryllides, such as Nb2 Be17. VBe12. are also *** room temperature deformation and high-temperature creep properties of these beryllides are repor4ed. At room temperature. NiBe exhibits certain tensile ductility (~ 1 .3%). but all other beryllides are essentially brittle. Nonetheless, these beryllides become ductile at temperatures above approximately 1000℃. Their creep properties are presented. The creep properties are compared with those of intermetallic aluminides. Also. a comparison is made between the ductile-to-brittle transition behaviour of intermetallic beryllides and that of aluminides. Although beryllides are generally oxidation resistant at high temperatures, some beryllides, e.g., ZrBe13, suffer the pest reaction during oxidation at intermediate tem peratures. The pest mechanisms are proposed

关键词： BeO Res AIME Structure and Deformation of Intermetallic Beryllides MPa

Optimization of phenol degradation by candida tropicalis Z-04 using Plackett-Burman design and response surface methodology

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Journal of Environmental Sciences 2011年第1期23卷 22-30页

作者： Jiangya Zhou Xiaojuan Yu Cong Ding Zhiping Wang Qianqian Zhou Hao Pao Weimin ca School of Environmental Science and Engineering Shanghai Jiaotong University Dongchuan Road 800 Shanghai 200240 China.

Statistical experimental designs were used to optimize the process of phenol degradation by candida tropicalis Z-04, isolated from phenol-degrading aerobic granules. The most important factors influencing phenol degradation （p 〈 0.05）, as identified by a two-level Plackett-Burman design with 11 variables, were yeast extract, phenol, inoculum size, and temperature. Steepest ascent method was undertaken to determine the optimal regions of these four significant factors. Central composite design （CCD） and response surface analysis were adopted to further investigate the mutual interactions between these variables and to identify their optimal values that would generate maximum phenol degradation. The analysis results indicated that interactions between yeast extract and temperature, phenol and temperature, inocuhim size and temperature affected the response variable （phenol degradation） significantly. The predicted results showed that the maximum removal efficiency of phenol （99.10%） could be obtained under the optimum conditions of yeast extract 0.41 g/l, phenol 1.03 g/l, inoculum size 1.43% （V/V） and temperature 30.04℃. These predicted values were further verified by validation experiments. The excellent correlation between predicted and experimental values confirmed the validity and practicability of this statistical optimum strategy. This study indicated the excellent ability of C. tropicalis Z-04 in degrading high-strength phenol. Optimal conditions obtained in this experiment laid a solid foundation for further use of this microorganism in the treatment of highstrength phenol effluents.

关键词： phenol degradation candida tropicalis Z-04 optimization Plackett-Burman design response surface methodology

Deformation of metallic glasses with special emphasis in supercooled liquid region

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中国有色金属学会会刊：英文版 2002年第4期12卷 726-733页

作者： T.G.Nieh (lawrence livermore National laboratory, l 350, PO Box 808, livermore, ca 94551, usA) lawrence livermore National laboratory L-350 PO Box 808 Livermore CA 94551 USA

Upon deforming a metallic glass at low temperatures, shear tends to localize and this leads to a brittle behavior. However, in the high temperature, and particularly in the supercooled liquid region, homogeneous deformation begins to take place. A bulk amorphous Zr 10Al 5Ti 17.9Cu 14.6Ni alloy was observed to exhibit the Newtonian behavior at low strain rates but becomes non Newtonian at high strain rates in the supercooled liquid region. Structures of the amorphous material, both before and after deformation, were examined using X ray diffraction and high resolution electron microscopy. Results showed the presence of nanocrystallites in the deformed samples. Thus, the non Newtonian behavior is attributable to the concurrent crystallization of the amorphous structure during deformation. A mechanistic model is presented to interpret the observed non Newtonian result. A phenomenological approach is also used to develop the deformation map for bulk metallic glasses in the supercooled liquid region.

关键词：非晶合金金属玻璃超塑性过度冷却液体层

Environmental Occurrence of Selenium in Waters and Related Health Significance

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Biomedical and Environmental Sciences 1997年第2期10卷 292-299页

作者： JANE l. VAlENTINE(School of Public Health, University of calIfornia at los Angeles, los Angeles, ca 90024, usA) School of Public Health University of California at Los Angeles 90024 USA.

Appreciable amounts of selenium in spring and well waters can be found due to geological occurrence. Concentrations of as much as 400 9000 μg/l have been reported in U. S. *** levels are 8 to 180 times the current EPA drinking water standard and approximate dietary exposures of 4900μg in selenosis regions of China. Reviews of health significance of the elevated drinking water exposures to U. S. populations revealed elevated concentrations of selenium in urine and blood. A decrease in glutathione peroxidase activity in such instances was noted. However noticeable symptoms and signs seem absent in studies reviewed. A comparison of intake levels (diet or drinking water) to urinary excretion for residents of China and the U. S. produced a correlation coefficient, r = 0. 82 (P lable

关键词： In Am Environmental Occurrence of Selenium in Waters and Related Health Significance

Shear strength behavior of geotextile/geomembrane interfaces

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 638-645页

作者： Belén M.Bacas Jorge caizal Heinz Konietzky Terrasolum S.l.Geotechnical Engineering Technology Development Center of University of Cantabria(CDTUC) School of Civil Engineering University of Cantabria Geotechnical Institute TU Bergakademie Freiberg

This paper aims to study the shear interaction mechanism of one of the critical geosynthetic interfaces,the geotextile/geomembrane, typically used for lined containment facilities such as landfills. A largedirect shear machine is used to carry out 90 geosynthetic interface tests. The test results show a strainsoftening behavior with a very small dilatancy （〈0.5 mm） and nonlinear failure envelopes at a normalstress range of 25e450 kPa. The influences of the micro-level structure of these geosynthetics on themacro-level interface shear behavior are discussed in detail. This study has generated several practicalrecommendations to help professionals to choose what materials are more adequate. From the threegeotextiles tested, the thermally bonded monofilament exhibits the best interface shear strength underhigh normal stress. For low normal stress, however, needle-punched monofilaments are *** the regular textured geomembranes tested, the space between the asperities is an important *** closer these asperities are, the better the result achieves. For the irregular textured geomembranestested, the nonwoven geotextiles made of monofilaments produce the largest interface shear strength.

关键词： Geotextiles Geomembranes landfills Fiber length Roughness Shear strength Friction angle

Comparative transcriptomics of anadromous and resident brook charr Salvelinus fontinalis before their first salt water transition

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Current Zoology 2012年第1期58卷 158-170页

作者： Boulet, Marylène Normandeau, Éric Bougas, Bérénice Audet, Céline mboulet@ubishops.ca Bernatchen, louis IBIS (Institut de Biologie Intégrative et des Systèmes) Université Laval Québec QC G1V 0A6 Canada ISMER Université du Québec à Rimouski Rimouski QC G5L 3A1 Canada

Most salmonid taxa have an anadromous life history strategy, whereby fish migrate to saltwater habitats for a growth period before returning to freshwater habitats for spawning. Moreover, several species are characterized by different life history tactics whereby resident and anadromous forms may occur in genetically differentiated populations within a same species, as well as polymorphism within a population. The molecular mechanisms underlying the physiological differences between anadromous and resident forms during the first transition from freshwater to saltwater environments are only partially understood. Insofar re- search has typically focused on species of the genus Salmo. Here, using a 16,000 cDNA array, we tested the hypothesis that ana- dromous brook charr Salvelinus fontinalis are characterized by differences in their transcriptome relative to resident brook charr before the anadromous fish migration. Families originating from parapatric populations of anadromous and resident charr were reared in controlled environments mimicking natural temperature and photoperiod, and sampled in spring, while still in fresh wa- ter. While anadromous and resident charr showed similar transcriptome profiles in white muscle, they were characterized by striking differences in their gill transcriptome profiles. Genes that were upregulated in the gills of anadromous charr were princi- pally involved in metabolism （mitochondrial electron transport chain, glucose metabolism, and protein synthesis）, development （tissue differentiation） and innate immunity. We discuss the nature of these transcriptomic differences in relation to molecular mechanisms underlying the expression of anadromous and resident life history tactics and suggest that the anadromous charr express some of the molecular processes present in other migratory salmonids [Current Zoology 58 （1）： 158-170, 2012].

关键词： Transcriptome life history tactics Anadromy Migration to salt water Ecotypes Salmohids

MGMT and MlH1 methylation in Helicobacter pylori-infected children and adults

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World Journal of Gastroenterology 2013年第20期19卷 3043-3051页

作者： Marisa C Alvarez Juliana C Santos Nathália Maniezzo Marcelo S ladeira Artur lC da Silva Isabel ca Scaletsky José Pedrazzoli Jr Marcelo l Ribeiro Unidade Integrada de Farmacologia e Gastroenterologia Universidade So FranciscoBragan a Paulista 12916-900SPBrazil Programa de Pós Gradua o em Genética e Biologia Molecular State University of CampinasCampinas 13083-970SPBrazil Departamento de Clínica Médica UNESPBotucatu 18618-970SPBrazil Departamento de Genética Universidade Federal do ParáBelém 68400-000PABrazil Departamento de Microbiologia Imunologia e ParasitologiaUniversidade Federal de So PauloSo Paulo 04021-001SPBrazil

AIM:To evaluate the association between Helicobacter pylori(***) infection and MlH1 and MGMT methylation and its relationship with microsatellite instability(MSI).METHODS:The methylation status of the MlH1 and MGMT promoter region was analysed by methylation specific methylation-polymerase chain reaction(MSPPCR) in gastric biopsy samples from uninfected or ***-infected children(n = 50),from adults with chronic gastritis(n = 97) and from adults with gastric cancer(n = 92).MlH1 and MGMT mRNA expression were measured by real-time PCR and normalised to a constitutive gene(β actin).MSI analysis was performed by screening MSI markers at 4 loci(Bat-25,Bat-26,D17S250 and D2S123) with PCR;PCR products were analysed by single strand conformation polymorphism followed by silver *** analyses were performed with either the χ 2 test with Yates continuity correction or Fisher's exact test,and statistical significance for expression analysis was assessed using an unpaired Student's ***:Methylation was not detected in the promoter regions of MlH1 and MGMT in gastric biopsy samples from children,regardless of *** infection *** MGMT promoter was methylated in 51% of chronic gastritis adult patients and was associated with *** infection(P lated in 66% of gastric cancer patients,and the difference in the percentage of methylated samples between these patients and those from ***-infected chronic gastritis patients was statistically significant(P lH1 methylation frequencies among ***-infected and non-infected chronic gastritis adult patients were 13% and 7%,*** observed methylation of the MlH1 promoter(39%) and increased MSI levels(68%) in samples from gastric cancer patients in comparison to samples from ***-infected adult chronic gastritis patients(P ly).The frequency of promoter methylation for both genes was higher in gastric cancer sam

关键词： Helicobacter pylori Microsatellite instability Promoter methylation MlH1 MGMT Gastric cancer

A two-configuration study on the photodetachment cross-section for the 3σ_u channel of F_2^-

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Science China Mathematics 1997年第4期40卷 432-435页

作者：孙卫国 R.M. Pitzer C.W. McCurdylawrence livermore National laboratory P.O.Box 5509 l-561 livermore ca 94550 U.S.A. Department of Applied Chemistry Sichuan Union University Chengdu 610065 China Department of Chemistry Ohio State University Columbus Ohio 43210 U.S.A.

An unusual resonance feature of the photodetachment cross-section for the 3σu channel of F2- observed in the early static-exchange study is confirmed by using correlated target (F2) wavefunctions determined by configuration interaction (CI). The magnitude of the cross-sections is lowered from that in earlier calculation by the potential of the correlated target.

关键词： resonance cross-section photodetachment configuration-interaction.x