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Amino acids composition and oxygen isotopes in the Shisr 033 CR chondrite
Deformed Statistics Kullback-Leibler Divergence Minimization within a Scaled Bregman Framework
The generalized Kullback-Leibler divergence (K-Ld) in Tsallis statistics
[constrained by the additive duality of generalized statistics (dual
generalized K-Ld)] is here reconciled with the theory of Bregman divergences
for expectations defined by normal averages, within a measure-theoretic
framework. Specifically, it is demonstrated that the dual generalized K-Ld is a
scaled Bregman divergence. The Pythagorean theorem is derived from the minimum
discrimination information-principle using the dual generalized K-Ld as the
measure of uncertainty, with constraints defined by normal averages. The
minimization of the dual generalized K-Ld, with normal averages constraints, is
shown to exhibit distinctly unique features.Comment: 16 pages. Iterative corrections and expansion
Haricots verts congelés : modélisation de la diminution de l’intensité de la couleur et de la teneur en chlorophylle
Colour changes and chlorophyll degradation of frozen green beans (Phaseolus vulgaris, L., variety bencanta) were
studied during 250 days of storage at 7, 15 and 30 C. Chlorophyll a and b losses and colour Hunter a and b coordinates
and total colour difference (TCDH) changes were successfully described by first order and reversible first
order models, respectively. The temperature effect was described by the Arrhenius law. Disagreement between the
colour co-ordinates and chlorophyll content was obtained. Therefore, chlorophyll content is not a good colour index of
frozen green beans. The results emphasise that colour is a more important parameter to assess frozen green beans
visual quality. # 2002 Elsevier Science Ltd and IIR. All rights reserved
Green beans (Phaseolus vulgaris, L.) quality loss upon thawing
Frozen green beans (Phaseolus vulgaris, L.) thawing is one of the operations that compromises significantly quality. The present
research aims at studying the effects of thawing, at environmental and refrigeration temperatures, on the quality profile of a frozen
green beans package. Quality losses were computationally evaluated, using a simulation system based on object-oriented technologies.
Simulations show that sensory parameters, such as flavour and colour, are more sensitive to thawing at environmental
temperatures, than nutritional parameters, such as vitamin C and starch contents.
The study demonstrates that green beans quality retention is also influenced by packaging materials, with different degrees of
thermal insulation, and environmental conditions, such as temperature and surface heat convection coefficients.
Important conclusions are discussed on shelf-life limiting quality parameters during thawing and temperature abuses, as well as
on thawing green vegetables to maximise their quality profile. Results emphasise that the principle of high-temperature–short-times
is not directly applicable to frozen green beans thawing. Furthermore, simulations lead to the conclusion that overall quality profile
is maximised by thawing under refrigeration temperatures
Inverse problem methodology for thermal-physical properties estimation of frozen green beans
Frozen green beans (Phaseolus vulgaris, L.) thermal conductivity (k) and heat capacity (Cp) were determined experimentally by a
one dimensional finite difference (transient method) and differential scanning calorimetry, respectively. Thermal properties were also
estimated by the inverse problem methodology (IPM). Heat capacity and thermal conductivity behaviour with temperature were
modelled by the Schwartzberg equations and linear relationship, respectively below and above the melting point. These equations
were used inside a finite element model (FEM) to simulate green beans phase transition under thawing conditions. The sequential
simplex method was used to minimise the error vector of the FEM inverse problem, to estimate thermal capacity and thermal
conductivity. The accuracy of thermal-physical properties estimated by the two methodologies was compared with data from literature.
The thermo-physical properties estimated by the IPM converged for physically meaningful values. Important conclusions
were obtained about errors in model predictions. Furthermore, the IPM thermal properties increased the accuracy of simulations,
especially during phase transition
Equine infectious anemia : prevalence in working equids of livestock herds, in Minas Gerais, Brazil
Estimaram-se, no estado de Minas Gerais, a prevalência e a distribuição espacial da anemia infecciosa eqüina (AIE) em propriedades com eqüídeos de serviço. As amostras de sangue, de 6540 eqüídeos de 1940 rebanhos foram coletadas no período de setembro de 2003 a março de 2004, nos 853 municípios do estado. Utilizaram-se dois testes de laboratório em seqüência: ELISA, usando-se antígeno recombinante gp90, e imunodifusão em gel de ágar (IDGA). As prevalências foram de 5,3% [IC=4,3 a 6,3%] para rebanhos e de 3,1% [IC=2,2 a 3,9%] para animais. O estado de Minas Gerais foi considerado área endêmica para AIE. As mais altas prevalências para rebanhos e para animais foram encontradas na região Norte/Noroeste, seguida pela região Vale do Mucuri/Jequitinhonha. ___________________________________________________________________________________________________________ ABSTRACTThe prevalence and spatial distribution of equine infectious anemia (EIA) were estimated in livestock herds where equids were used as draft power and for transportation in the State of Minas Gerais, Brazil. Serum samples were collected from September/2003 to March/2004 in 853 municipalities of the state. The sample comprised 6,540 equids from 1,940 herds. Two laboratorial tests were performed in sequence: ELISA using a recombinant gp90 protein, following by the AGID. The prevalence in the herds was estimated in 5.3% [CI = 4.3 to 6.3%], and 3.1% [CI = 2.2 to 3.9%] of the animals tested were positive. Minas Gerais was considered an endemic region for EIA. The highest prevalence for herds and animals was found in North/Northwest region (strata) followed by Vale do Mucuri/Jequitinhonha region
The effect of home storage conditions and packaging materials on the quality of frozen green beans
Home storage is the final step of the frozen foods distribution chain, and little is known on how it affects the products quality.
The present research describes frozen green beans (Phaseolus vulgaris, L.) quality retention profile during the recommended
‘star marking’ system dates, at the storage temperatures of þ5,26, 212 and 218 8C (along 1, 4, 14 and 60 days, respectively).
The quality profile was assessed by a simulation system. Simulations were set by a response surface methodology to access
the effect of different packaging materials (thermal conductivities and thickness), surface heat transfer coefficient, and
refrigerator dynamics (effect of refrigeration cycles at the different storage temperatures) on the average retentions of Ascorbic
Acid, total vitamin C, colour and flavour.
Green beans quality losses along frozen storage are significantly influenced by temperature, refrigerator dynamics and kinetic
properties. Quality is also highly dependent on packaging materials thermal insulation (e.g. at temperatures above the melting
point). Temperature cycles inside frozen chambers have a long term effect, and at the higher storage temperatures (e.g.
T . 26 8C) are detrimental to frozen green beans quality after shorter periods
Simulation of green beans (Phaseolus vulgaris, L.) quality loss throught the frozen foods distribution chain
Fitting the integrated Spectral Energy Distributions of Galaxies
Fitting the spectral energy distributions (SEDs) of galaxies is an almost
universally used technique that has matured significantly in the last decade.
Model predictions and fitting procedures have improved significantly over this
time, attempting to keep up with the vastly increased volume and quality of
available data. We review here the field of SED fitting, describing the
modelling of ultraviolet to infrared galaxy SEDs, the creation of
multiwavelength data sets, and the methods used to fit model SEDs to observed
galaxy data sets. We touch upon the achievements and challenges in the major
ingredients of SED fitting, with a special emphasis on describing the interplay
between the quality of the available data, the quality of the available models,
and the best fitting technique to use in order to obtain a realistic
measurement as well as realistic uncertainties. We conclude that SED fitting
can be used effectively to derive a range of physical properties of galaxies,
such as redshift, stellar masses, star formation rates, dust masses, and
metallicities, with care taken not to over-interpret the available data. Yet
there still exist many issues such as estimating the age of the oldest stars in
a galaxy, finer details ofdust properties and dust-star geometry, and the
influences of poorly understood, luminous stellar types and phases. The
challenge for the coming years will be to improve both the models and the
observational data sets to resolve these uncertainties. The present review will
be made available on an interactive, moderated web page (sedfitting.org), where
the community can access and change the text. The intention is to expand the
text and keep it up to date over the coming years.Comment: 54 pages, 26 figures, Accepted for publication in Astrophysics &
Space Scienc
Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
This paper reports a measurement of D*+/- meson production in jets from
proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the
CERN Large Hadron Collider. The measurement is based on a data sample recorded
with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets
with transverse momentum between 25 and 70 GeV in the pseudorapidity range
|eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay
chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate
is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for
D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z <
1. Monte Carlo predictions fail to describe the data at small values of z, and
this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table,
matches published version in Physical Review
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