4,215 research outputs found
Yeast metabolism in fresh and frozen dough : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New Zealand
Author also known as SM LovedayFresh bakery products have a very short shelf life, which limits the extent to which manufacturing can be centralised. Frozen doughs are relatively stable and can be manufactured in large volumes, distributed and baked on-demand at the point of sale or consumption. With appropriate formulation and processing a shelf life of several months can be achieved.Shelf life is limited by a decline in proofing rate after thawing, which is attributed to a) the dough losing its ability to retain gas and b) insufficient gas production, i.e. yeast activity. The loss of shelf life is accelerated by delays between mixing and freezing, which allow yeast cells the chance to ferment carbohydrates.This work examined the reasons for insufficient gas production after thawing frozen dough and the effect of pre-freezing fermentation on shelf life. Literature data on yeast metabolite dynamics in fermenting dough were incomplete. In particular there were few data on the accumulation of ethanol, a major fermentation end product which can be injurious to yeast.Doughs were prepared in a domestic breadmaker using compressed yeast from a local manufacturer and analysed for glucose, fructose, sucrose, maltose and ethanol. Gas production after thawing declined within 48 hours of frozen storage. This was accelerated by 30 or 90 minutes of fermentation at 30;C prior to freezing.Sucrose was rapidly hydrolysed and yeast consumed glucose in preference to fructose. Maltose was not consumed while other sugars remained. Ethanol, accumulated from consumption of glucose and fructose, was produced in approximately equal amounts to CO2, indicating that yeast cells metabolised reductively.Glucose uptake in fermenting dough followed simple hyperbolic kinetics and fructose uptake was competitively inhibited by glucose. Mathematical modelling indicated that diffusion of sugars and ethanol in dough occurred quickly enough to eliminate solute gradients brought about by yeast metabolism
Converting SrI <sub>2</sub> :Eu <sup>2+</sup> into a near infrared scintillator by Sm <sup>2+</sup> co-doping
The luminescence and scintillation properties of SrI 2 single crystals doped with 5% Eu 2+ and 0.05%, 0.2% and 0.5% Sm 2+ are evaluated. X-ray excited and photoluminescence measurements show energy transfer from excited Eu 2+ ions to Sm 2+ ions. At a concentration of 0.5% Sm 2+ , the luminescence consists almost entirely of 740 nm emission from Sm 2+ 5d-4f transitions. Co-doping SrI 2 :5% Eu 2+ with Sm 2+ provides a novel method to bypass the self-absorption problem encountered in large SrI 2 :Eu 2+ crystals and, at the same time, provides a unique near-infrared emitting scintillator with a light yield of approximately 40,000 photons/MeV. Accepted Author ManuscriptRST/Fundamental Aspects of Materials and EnergyRST/Luminescence Material
'Laws 'Needefull in Later to be Abrogated': Intersex and the Sources of Christian Theology
This is the author accepted manuscript. The final version is available from Palgrave Macmillan via the DOI in this record
Introduction: Troubling Bodies?
This is the author accepted manuscript. The final version is available from Palgrave Macmillan via the DOI in this record
Neutral sphingomyelinase is modulated by glutathione in keratinocytes UVB-induced apoptosis
The sphingomyelin pathway is an ubiquitous, evolutionary conserved signaling system which plays a role in intracellular signal transduction. The action of a ligand binding to a surface receptor results in early activation of the enzyme sphingomyelinase (SMases) with consequent hydrolysis of membrane sphingomyelin (SM) and generation of ceramide. Increase in intracellular ceramide level is followed by three major cellular responses: cell growth arrest, induction of cell differentiation and/or induction of apoptosis. Recent evidences have shown that reduced glutathione (GSH), but not other antioxidative agent, is able to inhibit apoptotic cell death and necrosis induced by hypoxia in PC12 cells. This protective effect is mediated by GSH direct inhibition of neutral SMase activity and ceramide formation. In the present study we report that GSH inhibits activation of neutral SMases and generation of ceramide and partially prevents apoptotic cell death induced by UVB radiation in keratinocytes. Normal human keratinocytes were cultivated with mitomycin-treated 3T3 cells in Dulbecco’s modified Eagle’s medium/Ham’s F12 medium. At preconfluency cells were incubated with GSH for 2h and then irradiated with a UVB dose of 75mJ per cm2. At different times after UVB irradiation, cells were harvested for in vitro measurement of neutral SMaese activity, lipid extraction and Western blot analysis. In vitro measurement of neutral SMase activity showed an early induction 15 min after exposure with a subsequent decrease to control level after 2h. Exposure to UVB radiation resulted in a rapid sphingomyelin hydrolysis and generation of ceramide as measured by TLC analysis. The ceramide accumulation started at 15 min after UV exposure and progressively increased up to 24h. Addition of GSH significantly inhibited activation of neutral SMase and generation of ceramide in UVB-treated keratinocytes. Moreover UVB-induced cleavage of PARP, a marker of the apoptotic response, was partially inhibited by GSH treatment. This data indicate that GSH plays a critical role in UVB signaling pathway regulating neutral SMase activity
Intrafullerene electron transfers in Sm-containing metallofullerenes: Sm@C-2n (74 <= 2n <= 84)
The electronic properties of Sm-containing metallofullerenes, Sm@C-74, Sm@C-76 (I, II), Sm@C-78, Sm@C-80, Sm@C-82 (I, II, III) and Sm@C-84 (I, II, III), are characterized by UV-Vis-NIR absorption spectroscopy and electron energy-loss spectroscopy (EELS). the UV-Vis-NIR absorption spectra of Sm@C-74, Sm@C-80, Sm@C-82 (I, II, III) and Sm@C-84 (I, II) are quite similar to those of the corresponding Ca, Sr, Ba, Eu, Tm, Yb-based metallofullerenes. In contrast, the absorption spectra of Sm@C-76 (I, II), Sm@C-78 and Sm@C-84(III) show a novel feature: the onset for Sm@C-78 is observed similar to 2600 nm, which corresponds to a small band gap (similar to0.5 eV). Furthermore, the oxidation states of Sm atom in the various fullerene cages are investigated by EELS, which reveals that the Sm atom takes +2 oxidation state in the fullerene cages. A probable rationale for the tendency to have the Sm2+ state is presented based on a simple thermochemical cycle model. (C) 2001 by Elsevier Science Inc.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000168906500014&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Biochemical Research MethodsBiochemistry & Molecular BiologyComputer Science, Interdisciplinary ApplicationsCrystallographyMathematical & Computational BiologySCI(E)EI30ARTICLE2244-2511
beta-decay spectroscopy of neutron-rich Sm-160,Sm-161,Sm-162 isotopes
Neutron-rich Sm-160,Sm-161,Sm-162 isotopes have been populated at the RIBF, RIKEN via beta decay for the first time. beta-coincident gamma rays were observed in all three isotopes including gamma rays from the isomeric decay of Sm-160 and Sm-162. The isomers in Sm-160 and Sm-162 have previously been observed but have been populated via beta decay for the first time. The isomeric state in Sm-162 is assigned a 4(-) nu 7/2(+)[633]circle times nu 1/2(-)[521] configuration based on the decay pattern. The level schemes of Sm-160 and Sm-162 are presented. The ground states in the parent nuclei Pm-160 and Pm-162 are both assigned a 6(-) nu 7/2(+)[633]circle times pi 5/2(-)[532] configuration based on the population of states in the daughter nuclei. Blocked BCS calculations were performed to further investigate the spin-parities of the ground states in Pm-160, Pm-161, and Pm-162, and the isomeric state in Sm-162.CPCI-S(ISTP)[email protected]
Discovering the Similarities between SM Communities and Other Organizations
The current research study is comparing and contrasting the demographic diversity of Sadomasochist (SM) organizations and other community organizations by surveying an SM organization and a non-SM organization. A confidential online survey was used to collect data. Fourteen general questions were asked: age, gender, sexual orientation, relationship status, number of children, ethnicity, highest level of education completed, employment, hours worked, income, religious affiliation, personality, infidelity and self esteem. Data was analyzed using Levene\u27s test and t-tests. Relationship status and religion were two differences between the SM group and the non SM group. The author discusses limitations and future directions of this study
INTERACTION MODE BETWEEN METHYLENE BLUE-Sm(III) COMPLEX AND HERRING SPERM DNA
Spectroscopic and viscosity methods were applied to investigate the interaction between methylene blue (MB)-Sm(III) complex and herring sperm DNA by using acridine orange as a spectral probe in Tris-HCl buffer (pH 7.40). By means of molar ratio method, the binding ratios between MB-Sm(III) and DNA were determined as n(Sm(III):)n(MB) = 1:3, n(MB-Sm(III) complex:)n (DNA) = 8 : 1, and the apparent molar absorption coefficient of epsilon(MB-Sm(III)-DNA) was found to be 7.01x10(5) M-1.cm(-1). The bonding constants at different temperatures K-292K(0) = 7.35x10(5) M-1, K-310K(0) = 1.25x10(5) M-1 were obtained by double reciprocal method. Thermodynamic function computation demonstrates that Delta rSm(circle minus) is the primary driving power of the interaction between MB-Sm(III) and herring sperm DNA. By combination analysis of the Scatchard method, circular dichroism spectroscopy and viscosity method, it suggests that the interaction mode between MB-Sm(III) complex and herring sperm DNA are a mixed binding, which contains partial intercalation and electrostatic interaction
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