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Understanding the radiosensitivity of plants, an important factor in crop mutation breeding programs, requires a thorough investigation of the factors that contribute to this trait. In this study, we used the highly radiosensitive wheat (Triticum aestivum L.) variety HY1 and J411, a γ-irradiation-insensitive control, which were screened from a natural population, to examine the factors affecting radiosensitivity, including free radical content and total antioxidant capacity, as well as the expression of TaKu70 and TaKu80 (DNA repair-related genes) as measured by real-time PCR. We also investigated the alternative splicing of this gene in the wild-type wheat ecotype by sequence analysis. Free radical contents and total antioxidant capacity significantly increased upon exposure of HY1 wheat to γ-irradiation in a dose-dependent manner. By contrast, in J411, the free radical contents exhibited a similar trend, but the total antioxidant capacity exhibited a downward trend upon increasing γ-irradiation. Additionally, we detected dose-dependent increases in TaKu70 and TaKu80 expression levels in γ-irradiated HY1, while in J411, TaKu70 expression levels increased, followed by a decline. We also detected alternative splicing of TaKu70 mRNA, namely, intron retention, in HY1 but not in J411. Our findings indicate that γ-irradiation induces oxidative stress and DNA damage in hexaploid wheat, resulting in growth retardation of seedlings, and they suggest that TaKu70 may play a causal role in radiosensitivity in HY1. Further studies are required to exploit these factors to improve radiosensitivity in other wheat varieties. [ABSTRACT FROM AUTHOR]

BACKGROUND Wheat with high anther culture ability would be beneficial for breeding. We aimed to screen a wheat germplasm to with high anther culture ability as well as good agronomic characteristics. RESULTS The F1 young spikes of winter wheat cross combination Yanfu188/Jimai37 were irradiated with gamma rays at a dose of 1.5 Gy to develop a new germplasm H307 with high anther culture ability. The proportion of green plantlets per 100 anthers ( GP/ 100A) of H307 was 14.50% which was higher than other H2 lines ( P < 0.05). Analysis over three successive years (2006-2008) revealed that the green plantlet regeneration ability of H307 remained high in all 3 years. Reciprocal crosses between H307 and Nongda3308 showed no significant differences in their values for calli per 100 anthers ( CA/ 100A), green plantlets per 100 calli ( GP/ 100C) and GP/ 100A ( P > 0.05). Five main wheat varieties used in production, namely Yumai68, Yanzhan4110, Bainongaikang58, Zhoumai18 and Xinmai18, were selected to cross with the new H307. CA/ 100A, GP/ 100C and GP/ 100A were used to assess the anther culture ability of F1 hybrids, demonstrating that the anther culture ability of H307 was heritable. CONCLUSION H307 possessed high anther culture ability that was heritable, which would be potential germplasm for improving wheat anther breeding ability. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: The electrical and optical characteristics of Zn+ ion-implanted Ni/Au ohmic contacts to p-GaN were investigated. After the preparation of Ni/Au electrode on the surface of p-GaN, the metal/p-GaN contact interface was doped by 35keV Zn+ implantation with fluences of 5×1015–5×1016 cm−2. Subsequent rapid thermal annealing of the implanted samples were carried in air at 200–400°C for 5min. Obvious improvements of the electrode contact characteristics were observed, i.e. the decrease of specific contact resistance and the increase of light transmittance. The lowest specific contact resistance of 5.46×10−5 Ωcm2 was achieved by 1×1016 cm−2 Zn+ implantation. The transmission enhancement of the electrodes was found as the annealing temperature rises. Together with the morphology and structure analyses of the contacts by scanning and transmission electron microscope, the corresponding mechanism for such an improvement was discussed. [Copyright &y& Elsevier]

Wheat is a staple food commodity grown worldwide, and wheat starch is a valuable source of energy and carbon that constitutes 80% of the grain weight. Manipulation of genes involved in starch synthesis significantly affects wheat grain weight and yield. TaSSIV plays an important role in starch synthesis and its main function is granule formation. To mine and stack more favorable alleles, single nucleotide polymorphisms (SNPs) of TaSSIV-A, B, and D were investigated across 362 wheat accessions by Ecotype-Targeting Induced Local Lesions IN Genome (EcoTILLING). As a result, a total of 38 SNPs in the amplified regions of three TaSSIV genes were identified, of which 10, 15, and 13 were in TaSSIV-A, B, and D, respectively. These 38 SNPs were evaluated by using KASP and six SNPs showed an allele frequency >5% whereas the rest were <5%, i.e., considered to be minor alleles. In the Chinese mini core collection, three haplotypes were detected for TaSSIV–A and three for TaSSIV–B. The results of an association study in the Chinese mini core collection with thousand grain weight (TGW) and spike length (SPL) showed that Hap-2-1A was significantly associated with TGW and Hap-3-1B with SPL. Allelic frequency and geographic distribution indicated that the favored haplotype (Hap-2-1A) has been positively selected in Chinese wheat breeding. These results suggested that the Kompetitive Allele Specific PCR (KASP) markers can be applied in starch improvement to ultimately improve wheat yield by marker assisted selection in wheat breeding. [ABSTRACT FROM AUTHOR]

Background: Substantial research has documented inequalities between US minorities and whites in meeting the eligibility criteria for the Medicare Part D medication therapy management (MTM) program. Even though the Centers for Medicare & Medicaid Services attempted to relax the eligibility criteria, a critical barrier to effective MTM reform is a lack of stronger evidence about the effects of MTM on minorities' health outcomes., Objective: To examine the effects of comprehensive medication review (CMR), an MTM core component, on racial and ethnic disparities in adherence to diabetes, hypertension, and hyperlipidemia medications among Medicare beneficiaries aged ≥65 years., Methods: This study used full-year 2017 Medicare Parts A, B, and D claims data, including MTM data, linked to the Area Health Resources Files. Racial and ethnic disparities in nonadherence to diabetes, hypertension, and hyperlipidemia medications were compared between CMR recipients and nonrecipients matched by their propensity scores. To determine the changes in racial and ethnic disparities after receiving CMR, a difference-in-differences framework was applied, by including in logistic regression analyses interaction terms between dummy variables for CMR receipt and each racial or ethnic minority group., Results: Compared with CMR nonrecipients, CMR recipients had significantly lower racial and ethnic disparities across the 3 outcome measures, with the exception of the difference between whites and blacks in nonadherence to diabetes medications. For example, compared with CMR nonrecipients, among CMR recipients the differences in the odds of nonadherence to hypertension medications were reduced, respectively, by 8% (95% confidence interval [CI], 0.88-0.96) between whites and blacks; by 18% (95% CI, 0.78-0.86) between whites and Hispanics; by 16% (95% CI, 0.77-0.91) between whites and Asians; and by 9% (95% CI, 0.85-0.98) between whites and other racial and ethnic groups., Conclusion: Receiving a CMR reduced the racial and ethnic disparities in adherence to diabetes, hypertension, and hyperlipidemia medications among Medicare beneficiaries aged ≥65 years. These findings provide critical empirical evidence that may inform the future design of the Medicare Part D MTM program, which is valuable for improving pharmacotherapy outcomes and could further realize its potential when additional people from racial and ethnic minorities are enrolled., (Copyright © 2021 by Engage Healthcare Communications, LLC.)