3,875 research outputs found
Hsian, the capital of Shensi : past and present
22 pageshttps://digitalrepository.trincoll.edu/moore/1023/thumbnail.jp
Microbiological profile in Serra ewes' cheese during ripening
The microflora of Serra cheese was monitored during a 35 d ripening period at three different periods within the ewe's lactation season. After 7 d ripening, the numbers of micro-organisms reached their maximum, and lactic acid bacteria (LAB) and coliforms were the predominant groups. Pseudomonads were not detected after 1 week of ripening. At all stages of ripening, cheeses manufactured in spring exhibited the lowest numbers of LAB and yeasts, whereas cheeses manufactured in winter showed the lowest numbers of coliforms and staphylococci.
Leuconostoc lactis was the most abundant LAB found in Serra cheese whereas Enterococcus faecium and Lactococcus lactis spp. lactis exhibited the highest decrease in percentage composition. Numbers of both Leuc. mesenteroides and Lactobacillus paracasei tended to increase throughout ripening. The most abundant coliform was Hafnia alvei. Klebsiella oxytoca was found in curd but declined in number during ripening. Staphylococcal flora of curd was mainly composed of Staphylococcus xylosus, Staph. aureus and Staph. epidermidis. Staphylococcus xylosus was the major species found at the end of ripening. Pseudomonas fluorescens, was the only Pseudomonas species isolated from the curd. Although a broad spectrum of yeasts were found in Serra cheese, Sporobolomyces roseus was the most abundant yeast isolated
Probing Dark Matter Substructure in Lens Galaxies
We investigate the effects of numerous dark matter subhalos in a galaxy-sized
halo on the events of strong lensing, to assess their presence as expected from
the cold dark matter scenario. Lens galaxies are represented by a smooth
ellipsoid in an external shear field and additional cold dark matter subhalos
taken from Monte Carlo realizations which accord with recent N-body results. We
also consider other possible perturbers, globular clusters and luminous dwarf
satellites, for comparison. We then apply the models to the particular lens
systems with four images, B1422+231 and PG1115+080, for which smooth lens
models are unable to reproduce both the positions of the images and their radio
flux ratios or dust-free optical flux ratios simultaneously. We show that the
perturbations by both globular clusters and dwarf satellites are too small to
change the flux ratios, whereas cold dark matter subhalos are most likely
perturbers to reproduce the observed flux ratios in a statistically significant
manner. This result suggests us the presence of numerous subhalos in lens
galaxies, which is consistent with the results of cosmological N-body
simulations.Comment: 19 pages, including 5 figures, ApJ in pres
Feasibility study on the use of probabilistic migration modeling in support of exposure assessment from food contact materials
The use of probabilistic approaches in exposure assessments of contaminants migrating from food packages is of increasing interest but the lack of concentration or migration data is often
referred as a limitation. Data accounting for the variability and uncertainty that can be expected in migration, for example, due to heterogeneity in the packaging system, variation of the temperature along the distribution chain, and different time of consumption of each individual package, are required for probabilistic analysis. The objective of this work was to characterize quantitatively the uncertainty and variability in estimates of migration. AMonte
Carlo simulation was applied to a typical solution of the Fick’s law with given variability in the input parameters. The analysis was performed based on experimental data of a model system (migration of Irgafos 168 from polyethylene into isooctane) and illustrates how important sources of variability and uncertainty can be identified in order to refine analyses.
For long migration times and controlled conditions of temperature the affinity of the migrant to the food can be the major factor determining the variability in the migration values (more than 70% of variance). In situations where both the time of consumption and temperature can vary, these factors can be responsible, respectively, for more than 60% and 20% of the variance in the migration estimates. The approach presented can be used with databases from consumption surveys to yield a true probabilistic estimate of exposure.info:eu-repo/semantics/acceptedVersio
A critical survey of predictive mathematical models for migration from packaging
The migration of chemicals from food contact materials into foods is an important issue in food safety.The assessment of materials compliance with regulations includes migration monitoring for many monomers and additives. However,it is recognized that predictive mathematical modelling can be used in many cases, to avoid or to reduce the effort on migration experiments. This article reviews the approaches followed to apply mathematical models to migration, particularly the models used, the approaches to estimate model parameters, and the systems used to experimentally validate the models. Conclusions on the issues requiring further research are drawn
Volatile compounds contribution of Hanseniaspora guilliermondii and Hanseniaspora uvarum during red wine vinifications
This work aims to investigate the contribution of a selected non-Saccharomyces yeast species, Hanseniaspora
guilliermondii, to higher alcohols, esters, fatty acids and heavy sulphur compounds composition
of red wine. Red grape must vinifications of 100 l were performed and an inoculated fermentation with
H. guilliermondii was compared to a spontaneous fermentation. The presence of apiculate yeasts was
observed in both fermentations; however, Hanseniaspora uvarum was the only apiculate yeast isolated
from the spontaneous fermentation. Apiculate yeasts dominated the fermentation until an ethanol
concentration of 6% (v/v) was attained and remained in considerable high levels for an ethanol
concentration of 12.5% (v/v). The grape must inoculated with H. guilliermondii led to the production of
wine with higher concentrations of 1-propanol, 2-phenylethyl acetate and 3-(methylthio)propionic acid,
and lower amounts of ethyl hexanoate, pentanoic acid, free fatty acids, 2-methyltetrahydrothiophen-3-
one and acetic acid-3-(methylthio)propyl ester, than wine resulting from the spontaneous fermentation.
The present study shows that the use of specific apiculate yeasts in grape must fermentations may lead to
the production of wines with different chemical profiles, emphasising the importance of Hanseniaspora
yeasts as mixed starter cultures with Saccharomyces cerevisiae, in winemaking.info:eu-repo/semantics/acceptedVersio
Characterization of patterns of food packaging usage in portuguese homes
This study aimed to further refine the exposure assessment of migrants from food-contact materials by
characterizing, at the household level, food packaging usage (amount and type) in Portuguese urban families.
Packages from domestic use were collected from a sample of 105 consumers from 34 households over a 30-day
period. Collected packages (more than 6000 items) were characterized in the laboratory and data were used to
estimate: (i) global packaging usage and food intake; (ii) the consumption factors (CF) that describe the fraction
of the daily diet expected to be in contact with specific packaging materials and (iii) the food-type factors (FTF)
that reflect the fraction of all food contacting each material which differ in nature according to six major types:
aqueous, acidic, alcoholic, milky, fatty and dry. The daily intake of packaged food and beverages consumed at
home ranged from 5–50 g kg 1 bw. Considering all materials, total package usage ranged from 0.1 to 0.6dm2
day 1 kg 1 bw. The ratio between package surface area in contact and the quantity of food was determined for all
packaging items collected and an average value of 25 dm2 kg 1 food was recorded. Data were gathered and
presented in a manner compatible with current probabilistic approaches to exposure assessment. In this way,
relevant consumption patterns from this type of population can be best represented in exposure assessments and
subsequent risk assessments.info:eu-repo/semantics/publishedVersio
From uncertain boundaries to uncertain identity: effects of entitativity threat on identity-uncertainty and emigration
This is the author accepted manuscript. The final version is available from Wiley via the DOI in this recordWhen people feel uncertain about their national identity, they may want to emigrate from
their nation. This uncertainty can arise when people are exposed to an alternative historical
narrative about their own national (ingroup) origins promoted by a neighboring nation
(outgroup). Drawing on uncertainty-identity theory we propose that the conditions that
promote this process would include when: (a) a revised history threatens the entitativity of
national identity, (b) people identify strongly with their nation, (c) a neighboring nation is
numerically large enough to transform its own view into a new shared reality, and (d) a new
interpretation of history is considered credible. We conducted an experiment in the context of
historical disputes between China (outgroup) and Korea (ingroup) (N = 160). We measured
Korean identification and manipulated type of identity threat (valence threat vs. entitativity
threat), relative group size (not salient vs. salient), and source credibility (low vs. how). Then,
we measured identity-uncertainty and emigration as dependent variables. As predicted,
hierarchical regression analyses yielded a significant four-way interaction on identityuncertainty. Simple slopes analyses revealed that entitativity (vs. valence) threat significantly
increased identity-uncertainty among high identifiers when the outgroup’s relative size was
salient and its view was credible. Further, the elevated identity-uncertainty strengthened
intentions to emigration from the ingroup. Implications for intergroup communications and
identity validation are discussed
Quantum Portfolios
Quantum computation holds promise for the solution of many intractable
problems. However, since many quantum algorithms are stochastic in nature they
can only find the solution of hard problems probabilistically. Thus the
efficiency of the algorithms has to be characterized both by the expected time
to completion {\it and} the associated variance. In order to minimize both the
running time and its uncertainty, we show that portfolios of quantum algorithms
analogous to those of finance can outperform single algorithms when applied to
the NP-complete problems such as 3-SAT.Comment: revision includes additional data and corrects minor typo
Inspiring radiographers to engage in research
Editorial piec
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