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Journal of Thermal Analysis and Calorimetry
Authors: J. Sabín, G. Prieto, Simona Sennato, Elena Blanco, Paula Messina, J. Ruso, Roberta Angelini, F. Bordi, and F. Sarmiento

Abstract  

The interactions of unilamellar vesicles obtained by the incorporation of (1,2,3,4,5,6)-tridecafluoro-hexadecane (F6H10 diblock) to dipalmitophosphatidyl-choline (DPPC), with Gd3+, Ca2+, Na+ ions were studied by electrophoretic measurements, dynamic light scattering and differential scanning calorimetry (DSC). Electrophoretic mobility measurements on unilamellar vesicles as a function of ion concentrations show that the vesicles adsorb the different ions employed. DSC has been used to determine the effect of diblock on the transition temperature (T c) and on the change of enthalpy (ΔH c) associated with the process.

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Abstract  

By comparison of three halogenated nicotinic acid derivatives, viz. 2–18F-, 6–18F-and 6–123I-nicotinic acid diethylamide (2–18F-NADA, 6–18F-NADA, 6–123I-NADA) the biodistribution of18F-and123I-radioactivity in mice was determined. For the two fluoro-compounds the results indicate nearly similar time-activity curves in almost all organs investigated, while the iodo-derivative exhibits significant differences: for the brain and the heart a complete elimination of123I-radioactivity takes place within 4 hours, time-activity curves of the liver and the kidneys show higher maximal accumulations compared to the fluorinated derivatives and activity in the stomach increases continously within a time period of 2 hours to a maximum which is about 5 times higher than that of 6–18F-NADA. For the lung drastic differences can also be observed in case of 6–123I-NADA which accumulates with a dose of about 40%/g already 30 seconds after injection and exceeds the corresponding values for 2–18F-NADA and 6–18F-NADA by a factor of about 6, followed by a biexponential decrease. De-fluorination reactions from the aromatic ring can be excluded, as could be shown by the low accumulation of18F-radioactivity in bones after application of 6–18F-NADA.

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Abstract

The hegemony of the Western higher education institutions in the global university market is being challenged by China. The top Chinese universities have significantly improved their international ranking positions. When it comes, however, to the ability of universities to attract foreign students and faculty, the Chinese higher education institutions' performance raises questions. The International Outlook scores of these universities, although showing an increasing trend, are still lacking behind the U.S. or Western European top universities. China is primarily a student ‘exporter.’ It also became a leading destination country for students from Asia or Africa, but it is still far from reaching the ‘international openness’ level of the U.S. or the UK universities. The publication networks of the top Chinese higher education institutions indicate that these universities prefer to publish with other Chinese institutions or the U.S. universities.

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Abstract

Why did China grow so fast in the past four decades? What were the main factors? Important ones were: attitude of government; opening to the world; role of culture; exploitation of technological gap; role of foreign trained students; and role of government in the creation of modern infrastructure. These factors are likely to play a much smaller role in the future while several negative factors –populism, trade wars, environmental obstacles, aging of the population, authoritarianism and others are likely to lead to significantly lower growth rates.

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Stem rust caused by Puccinia graminis f. sp tritici of wheat (Triticum aestivum L.) is one of the most destructive cereal diseases globally. Concern about the disease has increased since 1999 with the discovery in Uganda of a new virulent race of Pgt, designated as race TTKSK (also known as Ug99). The objectives of this experiment were to characterize the resistance and to determine the chromosomal location of the stem rust resistance in the spring wheat line PI 410966. A mapping population was developed from a cross between PI 410966 and a susceptible wheat line OK3040. An inoculation test with isolate 04KEN156/04 of race TTKSK was conducted at the USDA-ARS Cereal Disease Laboratory in the F6:7 generation, and the F6:7 phenotypic data were used to genetically map the resistance gene to the centromeric region on chromosome 2BS. The single locus explained the observed F6:7 resistant and susceptible scores. The location of the gene and molecular marker banding profiles of the diagnostic markers suggest that the stem rust resistance gene in PI 410966 could be a new gene, an allele of Sr36, or Sr36.

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The objective of this study was to develop an understanding about the genetics of terminal heat tolerance in wheat (Triticum aestivum L.). The minimum number of genes was assessed using Mendelian and quantitative genetic approach. Two crosses were made between heat tolerant and heat susceptible bread wheat cultivars: NW1014 × HUW468 and HUW234 × HUW468. Heat susceptible HUW468 was common in both the crosses. The F4, F5 and F6 generations were evaluated including F1 in two different dates of sowing (normal and very late) under field conditions in year 2006–07. The data was recorded for grain fill duration (GFD) and thousand-grain weight (TGW). Based on data of two dates, decline% and heat susceptibility index (HSI) of GFD and TGW were estimated. Heat tolerance in F1 showed absence of dominance. Estimation of genes using Mendelian approach in F4, F5 and F6 progenies (148–157) of the two crosses suggested that heat tolerance was governed by a minimum of three genes. Quantitative approach also indicated similar number of genes. The distribution of progeny lines in F4 and F6 supported the polygene nature of heat tolerance. These genes if mapped by molecular approach can play an important role through marker assisted selection (MAS) for developing improved thermo-tolerant lines of wheat.

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Abstract  

Oxyfluoride glass-ceramics based on the aluminosilicate glass-matrix with the nano-phase of fluoride is an interesting material for optoelectronics. A new glass from the SiO2–B2O3–Na2O–LaF3 system in which nanocrystallization of LaF3 could be obtained as well is presented. Thermal stability of glass and the crystalline phases formed upon heat treatment were determined by DTA/DSC and XRD methods, respectively. The effect of the glass composition on thermal stability was investigated by the SEM method. It has been found that the addition of LaF3 increases the tendency to decomposition of the borosilicate glass. In glasses with the ratio B2O3/(Na2O+3La2F6)<1 it is possible to obtain the immersed crystallization of LaF3 in transparent glassy matrix. The process is preceded by LaOF formation. Glasses with the composition B2O3/(Na2O+3La2F6)≥1 revealed the tendency to La(BSiO5) crystallization.

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Abstract  

Glasses have been synthesized in the system SiO2–Al2O3–Na2O–AlF3–LaF3–Er2O3. A base glass (in mol% 67SiO2–9Al2O3–20Na2O–Al2F6–3La2F6) was modified by 0.5, 0.75, 1, 1.25, 1.5, 2 and 5 mol% Er2O3, respectively. Glasses were prepared by conventional fusion method from 20 g batches. The glass transition temperature (T g), the jump-like changes of the specific heat (ΔC p) accompanying the glass transition and the enthalpy of crystallization (ΔH) were calculated. DTA measurements clearly reveal that the increase of the Er2O3 content in the glass changes the effects of crystallization and diminishes the thermal stability of the glassy network. In the same time the changes in the transition temperature are observed. The formation of NaLaF4 and Na1.45La9.31(SiO4)6(F0.9O1.1) as a main phase was confirmed. The diminishing of the thermal stability was connected with erbium which incorporated into Na1.45La9.31(SiO4)6(F0.9O1.1) structure.

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This study evaluated the effectiveness of an image sorter to select for kernel color within early generations of segregating hard winter wheat populations. The wheat crosses originated from different combinations of white and red parents. Three generations (F3, F4 and F5) of sorting were applied to six segregating populations. At each generation, samples of whitesorted, red-sorted, and unsorted populations, along with the parents of the populations, were planted in replicated trials at multiple locations. The sorter processed 1kg sized samples in ~30 min and samples were sorted for 108 plots per season. ~10% of the F3 populations were sorted and planted as white-sort population. This resulted in minimal changes in the % of white kernels. ~3% of the F4 and F5 populations were sorted and planted as white-sorted populations and significant advancement occurred. The F6 populations of white-sorted samples from Dakota Lake ranged from 80% to 92% white kernels. The F6 populations from Brookings ranged from 53% to 83% white kernels. Sorting for red seed decreased the frequency of white seed as compared to the unsorted reference populations; however reductions, of white seeds in the red populations, were modest and required three cycles of selection for significant effect. The effectiveness of the image-sorter varied with population and environment and sorting methods.

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The kinetics of isothermal decomposition of solid K2Zr2(O2)2F6·2H2O have been studied in the temperature range 100–226° under vacuum. The fractional decomposition α has been determined by measuring the pressure of evolved oxygen during pyrolysis with the help of a McLeod gauge. The α values ranged from 0.05 to 0.62. The αvs. t data showed that the kinetics are deceleratory throughout the course of the reaction. The initial part of the decomposition reaction could be best described by a unimolecular decay law, while the later stages obey contracting volume kinetics. The activation energies have been determined and the respective values for the above stages are 13.6 and 6.9 kcal·mole−1.

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