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The effects of preharvest factors on the accumulation of antioxidants in fruit peel, and their relationships to superficial scald development after cold storage of apples (Malus domestica Borkh.).
Superficial scald, a physiological disorder of apples, develops during storage, and is believed to result from the oxidation of farnesene to conjugated trienes. Antioxidants are believed to protect against this oxidation, thus providing scald resistance. The hypothesis examined in this study was that temperatures below 10\sp\circC before harvest facilitate the accumulation of antioxidants in the apple peel, and that this effect is enhanced by ripening and light. Cortland and Delicious apples were harvested following exposure to increasing hours below 10\sp\circC during three years. Cortland apples were sprayed with ethephon to induce ripening at warm temperatures, and were bagged in late August to produce ripening at low light intensities, both during two years. Percent inhibition of oxidation and water-soluble reducing activities, as well as concentrations of tocopherol, ascorbic acid, glutathione, farnesene, conjugated trienes and several pigments, were determined at harvest and following intervals of storage. Scald development was determined after 3 to 5 months of storage at 0\sp\circC. Correlations and regressions demonstrated that increasing exposure to temperatures below 10\sp\circC was the primary factor in development of scald resistance. Less resistance developed when low light intensity existed during cool periods. Ripening alone was only a small factor in development of scald resistance. Cool preharvest temperatures slightly increased the concentrations of tocopherol and carotenes, and slightly increased water-soluble reducing capacity and percent inhibition of oxidation. Ripening increased both percent inhibition of oxidation and total water-soluble reducing activities, and increased concentrations of tocopherol, carotenes and ascorbic acid. Reduced light intensity (bagging) decreased concentrations of tocopherol, carotenes, and ascorbic acid, as well as total water-soluble reducing capacity. However, percent inhibition of oxidation and glutathione were not significantly influenced. During storage, as conjugated trienes accumulated, the tocopherol and carotene concentrations increased, while total water-soluble reducing capacity, ascorbic acid, and glutathione decreased. Although some support is given to the widely accepted model of scald development, it was concluded that while antioxidants play a role in scald resistance, they are probably not the key factor
Ram pressure and dusty red galaxies - key factors in the evolution of the multiple cluster system Abell 901/902
We present spectroscopic observations of 182 disk galaxies (96 in the cluster
and 86 in the field environment) in the region of the Abell 901/902 multiple
cluster system, which is located at a redshift of . The presence
of substructures and non-Gaussian redshift distributions indicate that the
cluster system is dynamically young and not in a virialized state. We find
evidence for two important galaxy populations. \textit{Morphologically
distorted galaxies} are probably subject to increased tidal interactions. They
show pronounced rotation curve asymmetries at intermediate cluster-centric
radii and low rest-frame peculiar velocities. \textit{Morphologically
undistorted galaxies} show the strongest rotation curve asymmetries at high
rest-frame velocities and low cluster-centric radii. Supposedly, this group is
strongly affected by ram-pressure stripping due to interaction with the
intra-cluster medium. Among the morphologically undistorted galaxies, dusty red
galaxies have particularly strong rotation curve asymmetries, suggesting ram
pressure is an important factor in these galaxies. Furthermore, dusty red
galaxies on average have a bulge-to-total ratio higher by a factor of two than
cluster blue cloud and field galaxies. The fraction of kinematically distorted
galaxies is 75% higher in the cluster than in the field environment. This
difference mainly stems from morphological undistorted galaxies, indicating a
cluster-specific interaction process that only affects the gas kinematics but
not the stellar morphology. Also the ratio between gas and stellar scale length
is reduced for cluster galaxies compared to the field sample. Both findings
could be best explained by ram-pressure effects.Comment: Electronic version published in Astronomy and Astrophysics Volume
549, Page 0; 19 pages, 21 figure
Tully-Fisher analysis of the multiple cluster system Abell 901/902
We derive rotation curves from optical emission lines of 182 disk galaxies
(96 in the cluster and 86 in the field) in the region of Abell 901/902 located
at . We focus on the analysis of B-band and stellar-mass
Tully-Fisher relations. We examine possible environmental dependencies and
differences between normal spirals and "dusty red" galaxies, i.e. disk galaxies
that have red colors due to relatively low star formation rates. We find no
significant differences between the best-fit TF slope of cluster and field
galaxies. At fixed slope, the field population with high-quality rotation
curves (57 objects) is brighter by \Delta M_{B}=-0\fm42\pm0\fm15 than the
cluster population (55 objects). We show that this slight difference is at
least in part an environmental effect. The scatter of the cluster TFR increases
for galaxies closer to the core region, also indicating an environmental
effect. Interestingly, dusty red galaxies become fainter towards the core at
given rotation velocity (i.e. total mass). This indicates that the star
formation in these galaxies is in the process of being quenched. The
luminosities of normal spiral galaxies are slightly higher at fixed rotation
velocity for smaller cluster-centric radii. Probably these galaxies are
gas-rich (compared to the dusty red population) and the onset of ram-pressure
stripping increases their star-formation rates. The results from the TF
analysis are consistent with and complement our previous findings. Dusty red
galaxies might be an intermediate stage in the transformation of infalling
field spiral galaxies into cluster S0s, and this might explain the well-known
increase of the S0 fraction in galaxy clusters with cosmic time.Comment: Accepted for publication in Astronomy and Astrophysics; 16 pages, 14
figure
SECOND-ORDER DERIVATIVE UV SPECTROPHOTOMETRIC AND RP-HPLC METHODS FOR THE ANALYSIS OF VILDAGLIPTIN AND APPLICATION FOR DISSOLUTION STUDY
This study describes two analytical methods, by second-order derivative UV spectrophotometric by HPLC, for determination of vildagliptin, a drug used for treatment of type 2 Diabetes Mellitus that belongs to a therapeutic class called inhibitors of dipeptidyl peptidase 4. The methods were validated in accordance with ICH and USP requirements. Analyses by UV derivative method were performed at 220 nm, which was the zero crossing point of excipient solutions. HPLC was optimized and the analysis was carried out using a Zorbax Eclipse Plus RP-C8 column (150 mm × 4.6 mm, 5 μm), detection at 207 nm, and potassium phosphate buffer solution pH 7.0 : acetonitrile (85:15, v/v) as mobile phase. In dissolution test, the conditions used were 0.01 mol L-1 hydrochloric acid in 900 mL of dissolution medium, USP apparatus 2 (paddle) and 50 rpm stirring speed. Both methods were successfully applied for analysis of dissolution samples from marketed vildagliptin tablets
Investigating the Filled Gel Model in Cheddar Cheese Through Use of Sephadex Beads
Cheese can be modeled as a filled gel whereby milkfat globules are dispersed in a casein gel network. We determined the filler effects using Sephadex beads (GE Healthcare Life Sciences, Pittsburgh, PA) as a model filler particle. Ideally, such a model could be used to test novel filler particles to replace milkfat in low-fat cheese. Low-filler (6% particles), reduced-filler (16%), and full-filler (33%) cheeses were produced using either Sephadex beads of varying sizes (20 to 150 μm diameter) or milkfat. Small- and large-strain rheological tests were run on each treatment at 8, 12, and 18 wk after cheese manufacturing. Differences in rheological properties were caused primarily by the main effects of filler volume and type (milkfat vs. Sephadex), whereas filler size had no obvious effect. All treatments showed a decrease in deformability and an increase in firmness as filler volume increased above 25%, although the beads exhibited a greater reinforcing effect and greater energy recovery than milkfat
TB42: The Mycotoxic Effects of Fungi Isolated from Poultry Feed Ingredients: The Response of Ducklings and Performance of Commercial Broiler Chickens Fed Experimentally Infected Corn Diets
The present work, planned to investigate the possibility of mycotoxins occurring in feed ingredients fed to poultry in Maine, was designed with the following objectives: (1) to isolate fungi from poultry feed ingredients; (2) to grow the m separately on corn (the carbohydrate source of poultry rations) for later mixing into the diets; (3) to test the variously infected lots of this corn substrate for mycotoxicity by feeding ducklings, a bioindicator for toxins; (4) to determine the effects of aflatoxin and other mycotoxins from feed ingredients, on the performance of commercial broiler chickens; and (5) to appraise this response as a measure of toxicity of the fungi found in feed ingredients.https://digitalcommons.library.umaine.edu/aes_techbulletin/1159/thumbnail.jp
Spin-structures of N-boson systems with nonzero spins - an analytically solvable model with pairing force
A model is proposed to study the possible pairing structures of N-boson
systems with nonzero spin. Analytical solutions have been obtained. The
emphasis is placed on the spin-structures of ground states with attractive or
repulsive pairing force, and with or without the action of a magnetic field. A
quantity (an analogue of the two-body density function) is defined to study the
spin-correlation between two bosons in N-body systems. The excitation of the
system has also been studied.Comment: 10 pages, 2 figures, accepted by Few-Body System
Stellar science from a blue wavelength range - A possible design for the blue arm of 4MOST
From stellar spectra, a variety of physical properties of stars can be
derived. In particular, the chemical composition of stellar atmospheres can be
inferred from absorption line analyses. These provide key information on large
scales, such as the formation of our Galaxy, down to the small-scale
nucleosynthesis processes that take place in stars and supernovae. By extending
the observed wavelength range toward bluer wavelengths, we optimize such
studies to also include critical absorption lines in metal-poor stars, and
allow for studies of heavy elements (Z>38) whose formation processes remain
poorly constrained. In this context, spectrographs optimized for observing blue
wavelength ranges are essential, since many absorption lines at redder
wavelengths are too weak to be detected in metal-poor stars. This means that
some elements cannot be studied in the visual-redder regions, and important
scientific tracers and science cases are lost. The present era of large public
surveys will target millions of stars. Here we describe the requirements
driving the design of the forthcoming survey instrument 4MOST, a multi-object
spectrograph commissioned for the ESO VISTA 4m-telescope. We focus here on
high-density, wide-area survey of stars and the science that can be achieved
with high-resolution stellar spectroscopy. Scientific and technical
requirements that governed the design are described along with a thorough line
blending analysis. For the high-resolution spectrograph, we find that a
sampling of >2.5 (pixels per resolving element), spectral resolution of 18000
or higher, and a wavelength range covering 393-436 nm, is the most
well-balanced solution for the instrument. A spectrograph with these
characteristics will enable accurate abundance analysis (+/-0.1 dex) in the
blue and allow us to confront the outlined scientific questions. (abridged)Comment: 14 pages, 8 figures, accepted for publication in A
Indonesian couple’s pregnancy ambivalence and contraceptive use
CONTEXT: Recognizing pregnancy ambivalence is important for family planning policy and
programming efforts. Most studies on pregnancy ambivalence are based on data from women;
using partner’s perceived pregnancy intentions whenever partners are considered. This study
examines couple’s pregnancy ambivalence and the association with contraceptive use in
Indonesia.
METHOD: Matched couple data from the 2002-2003 Indonesia Demographic and Health Survey
are used to examine contraceptive use, fertility desires, and responses to whether a pregnancy in
the next few weeks would be a big problem, small problem or no problem. Inconsistent fertility
desires and responses to the problem question are used to define ambivalence. Response patterns
and concordance between partners is evaluated. Multivariate logistic regression analyses are used
to assess whether couple’s pregnancy ambivalence is associated with contraceptive use.
RESULTS: 71% of husbands and 54% of wives report that a pregnancy in the next few weeks
would be “no problem.” Couple’s concordance on the problem question is 63% (kappa statistic =
0.26) among contraceptive users and 61% (0.24) among non-users. In the multivariate analysis,
couples who were discordant on the problem question were 24% less likely to use contraception
than were couples in which both partners agreed a pregnancy would be a big or small problem.
Results were not statistically significant at p≥0.05 in a model with a disaggregated variable on
couple’s discordance that identified which partner was ambivalent; this might be related to small
cell sizes. Contraceptive use was also less likely for couples with discordant fertility desires.
CONCLUSION: Husbands and wives influence each other’s fertility attitudes and family
planning use. To improve effective contraceptive use and/or continuation, couple’s pregnancy
attitudes should be taken into account at the time of screening and method selection
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