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Journal of Thermal Analysis and Calorimetry
Authors:
R. Artiaga
,
A. Garcia
,
L. Garcia
,
A. Varela
,
J. Mier
,
S. Naya
, and
M. Grana

Abstract  

The nickel-titanium alloys are usually known as Shape Memory alloys because of their ability to return to some previously defined shape or size when subjected to the appropriate thermal procedure. Mechanical properties of a nickel titanium wire were investigated by DMTA using cylindrical tension mode. The Young"s modulus, the maximum strain and residual deformation have been calculated. Recovery of previously deformed samples was observed in constant stress temperature ramp tests. Relaxation stress behaviour at temperatures above the austenitic transformation has been studied. The strain and frequency ranges of linear response have been determined by dynamic experiments. Strain amplitude of 0.1% and frequency of 1 Hz have been chosen for the temperature ramp dynamic experiments. A big change between 65 and 95C is observed in the storage modulus. The values of E' at temperatures below and above the transition are essentially constant. Finally, the effects of the frequency at different temperatures have been examined.

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This study was aimed to analyze the effect of two different megadoses of α-tocopherol (vit E) in the antioxidant activity and red and white blood series of Wistar rats after a 180-min ultraendurance probe. Three groups of 10 rats were analyzed; VEAG: acute administration of a megadoses of 5,000 IU/kg of vit E the day before the probe; VECG: chronic administration of 1,000 IU/kg/day of vit E for 6 days before the probe; CG: placebo administration. VEAG presented white cells, red blood cells, hematocrit, hemoglobin values significantly higher than CG and VECG (p < 0.05). The mean corpuscular hemoglobin and lymphocytes concentrations were significantly higher in the VECG than in the other two groups (p < 0.05). Similarly, VEAG presented a significantly higher vit E blood concentration than VECG and CG (p < 0.05), and VECG than CG (p < 0.05). Finally, we found a significantly positive correlation between trolox equivalent antioxidant capacity (TEAC) and red blood cells concentration (r = 0.374) and a significantly inverse correlation between TEAC and blood lactate concentration (r = −0.365). Our findings suggest that acute vit E megadoses could protect against transitory sport anemia symptoms and increase the white blood cell count in comparison with the chronic dose and control groups after an ultraendurance probe.

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Cereal Research Communications
Authors:
E. Martínez-Cruz
,
E. Espitia-Rangel
,
H. Villaseñor-Mir
,
J. Molina-Galán
,
I. Benítez-Riquelme
,
A. Santacruz-Varela
, and
R. Peña-Bautista

The influence of allelic variants of HMW Gand LMWG on viscoelastic properties of dough was evaluated in parents and 98 recombinant lines derived from the crosses Rebeca F2000 × Verano S91 and Galvez M87 × Bacanora T88. Genotypes were grown at Roque, Guanajuato during the Spring-Summer of 2008. Studied traits were mixing time, mixing stability and over-mixing tolerance, general strength of the dough and tenacity/extensibility ratio. HMWG alleles 1, 2*, 17 + 18 and 5 + 10 favored the quality of the dough and variants 2 + 12 and 7 + 9 were associated with low levels of gluten strength. A 7 + 9 allele was associated with genotypes prone to form tenacious dough. Alleles Glu-A3c, Glu-A3e, Glu-B3g and Glu-B3h from the cross Rebeca F2000 × Verano S91 affected positively the quality of gluten, while allelic variants Glu-A3b, Glu-B3h and Glu-D3c in the cross Galvez M87 × Bacanora T88 were associated with higher quality standards and its counterparts Glu-A3c, Glu-B3j and Glu-D3b were associated to lower quality parameters. Results also shown interaction among loci, hence breeders need to be aware not only of the effect of individual alleles but also its interaction.

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