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991.
In the aquatic environment, mercury is readily methylated into its most toxic form of methylmercury. In this form, it enters the aquatic food chain and its concentrations increase in subsequent links, which decreases the quality of fish meat and poses risks to consumer health. Concentrations of methylmercury (MeHg) and total mercury (THg) were determined in the muscle tissues of 64 eel specimens measuring from 59 to 95 cm in length as functions of specimen size and weight. Risks posed to consumers by eel from different length classes were also assessed. The mean concentration of THg in all of the eel examined was 0.179 mg kg?1, but the range was from 0.028 to 0.487 mg kg?1. The mean concentration of MeHg was 0.147 mg kg?1, and the range was also wide from 0.023 to 0.454 mg kg?1. Accumulated MeHg and THg increased with eel body length. The percentage share of MeHg in THg also changed with specimen length, and there was a positive correlation between the concentrations of MeHg and THg. Risk assessment was performed based on the doses of THg and MeHg ingested with fish for several specimen length classes. Consuming the meat of eel measuring 80 cm in length increased the estimated weekly intake (EWI) of THg and MeHg twofold in comparison to that from specimens 60 cm in length and fourfold in specimens exceeding 90 cm in length. The percentage shares of the EWI in the tolerable weekly intake and the target hazard quotient coefficient also increased proportionally. Generally, concentrations of MeHg and THg in eel are below current limits and pose no risk to consumer health as long as the consumption of larger specimens is avoided. 相似文献
992.
3D‐Printed Cathodes of LiMn1−xFexPO4 Nanocrystals Achieve Both Ultrahigh Rate and High Capacity for Advanced Lithium‐Ion Battery
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Jiangtao Hu Yi Jiang Suihan Cui Yandong Duan Tongchao Liu Hua Guo Lingpiao Lin Yuan Lin Jiaxin Zheng Khalil Amine Feng Pan 《Liver Transplantation》2016,6(18)
A 3D‐printing technology and printed 3D lithium‐ion batteries (3D‐printed LIBs) based on LiMn0.21Fe0.79PO4@C (LMFP) nanocrystal cathodes are developed to achieve both ultrahigh rate and high capacity. Coin cells with 3D‐printed cathodes show impressive electrochemical performance: a capacity of 108.45 mAh g?1 at 100 C and a reversible capacity of 150.21 mAh g?1 at 10 C after 1000 cycles. In combination with simulation using a pseudo 2D hidden Markov model and experimental data of 3D‐printed and traditional electrodes, for the first time deep insight into how to achieve the ultrahigh rate performance for a cathode with LMFP nanocrystals is obtained. It is estimated that the Li‐ion diffusion in LMFP nanocrystal is not the rate‐limitation step for the rate to 100 C, however, that the electrolyte diffusion factors, such as solution intrinsic diffusion coefficient, efficiency porosity, and electrode thickness, will dominate ultrahigh rate performance of the cathode. Furthermore, the calculations indicate that the above factors play important roles in the equivalent diffusion coefficient with the electrode beyond a certain thickness, which determines the whole kinetic process in LIBs. This fundamental study should provide helpful guidance for future design of LIBs with superior electrochemical performance. 相似文献
993.
994.
Jin Xu Xiao-Long Jiang Min Deng Murphy Westwood Yi-Gang Song Si-Si Zheng 《Tree Genetics & Genomes》2016,12(5):90
Montane cloud forests (MCFs), with their isolated nature, offer excellent opportunities to study the long-term effects of habitat fragmentation and the impacts of climate change. Quercus arbutifolia is a rare oak in MCFs of southern China and Vietnam. Its isolated populations, small population size and unique ecological niche make this species vulnerable to climate change and habitat loss. In this study, we used chloroplast (cpDNA) and nuclear (ITS) DNA sequences to investigate genetic divergence patterns and demographic history of five of the six known populations of Q. arbutifolia. Considering its small population size and fragmentation, Q. arbutifolia has unexpectedly high genetic diversity. The time since the most recent common ancestor of all cpDNA haplotypes was c. 10.25 Ma, and the rapid diversification of haplotypes occurred during the Quaternary. The maximum clade credibility chronogram of cpDNA haplotypes suggests that the DM population (Daming Mountain, Guangxi province) diverged early and rapidly became isolated from other populations. The Pearl River drainage system may have been the main geographic barrier between DM and other populations since the late Miocene. ITS data suggests that population expansion occurred during the last interglacial of the Quaternary. The combined effects of pre-Quaternary and Quaternary climatic and geological changes were the main drivers to the current genetic diversity and distribution pattern of Q. arbutifolia. Because of the high between-population genetic differentiation and high within-population genetic diversity of Q. arbutifolia, conservation efforts should be implemented for all populations, but if conservation resources are limited, populations DM, YZ (Mang Mountain, Hunan province) and ZZ (Daqin Mountain, Fujian province) should have priority. 相似文献
995.
Octávio Serra José Manuel Donoso Roger Picañol Ignasi Batlle Werner Howad Iban Eduardo Pere Arús 《Tree Genetics & Genomes》2016,12(5):96
This paper proposes a new breeding strategy, marker-assisted introgression (MAI), to obtain lines of perennial species with a single introgressed fragment from a compatible species two generations after the interspecific hybrid. MAI allows enrichment of the genome of a species with genes from a wild or exotic relative in a short timeframe and with an intermediate step that allows a first exploration of genes/QTLs that the donor species can provide to the target crop. This method has three phases: (1) creating a large backcross one (BC1) population to select, with markers, a reduced number of individuals (15–30, called the prIL set) with a low number of introgressions; (2) phenotyping the prIL set for the traits of interest and inferring the inheritance and map position of segregating major genes/QTLs based on the known genotypes of the prILs; and (3) advancing selected lines carrying the traits of interest to a next generation of backcross or selfing to obtain individuals with a single introgression in the background of the elite commercial germplasm. The proof of concept of this strategy was implemented by using peach as the recurrent species and almond as the donor. The whole process can be done in 9–10 years as the identification of the first line with one introgression was after 5 years (2006–2011), and 4–5 additional years are needed for phenotypic evaluation of selected lines. The expansion of this method to other perennial clonally propagated crops and to other species of Prunus compatible with peach is discussed. 相似文献
996.
Zn‐Air Batteries: Composites of a Prussian Blue Analogue and Gelatin‐Derived Nitrogen‐Doped Carbon‐Supported Porous Spinel Oxides as Electrocatalysts for a Zn–Air Battery (Adv. Energy Mater. 22/2016)
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997.
998.
Paola Ruffa Stefano Raimondi Paolo Boccacci Simona Abbà Anna Schneider 《Tree Genetics & Genomes》2016,12(3):50
A great number of flavored grape varieties, of significant oenological potential, are traditionally cultivated in north-western Italy, besides the renowned “Moscato bianco” (syn. “Muscat à petits grains blancs”). Understanding their origin, besides its historical and scientific interest, would help to increase market appeal and consequently facilitate the commercial exploitation of these products. Twenty-four aromatic genotypes were investigated for their identity, kinship relations, and genetic origins through molecular markers (SSR and SNPs) supported by plant morphology and historical information. Flavored grape genotypes from other regions, possible ancestors, and reference cultivars of known pedigree were also included in the analysis. Kinship analysis used a likelihood-based approach (IBS, IBD, relatedness coefficients, and likelihood ratios) to achieve strong statistical support. The analyses revealed two possible leading genitors, in turn closely related by a parent/offspring relationship: “Moscato bianco” and “Malvasia aromatica di Parma,” a female grape cultivar that is today almost extinct. The outlined molecular and statistical approach could be applied for the investigation on the origin of ancient traditional cultivars of other vegetative propagated species. 相似文献
999.
Lithium‐Ion Batteries: 3D‐Printed Cathodes of LiMn1−xFexPO4 Nanocrystals Achieve Both Ultrahigh Rate and High Capacity for Advanced Lithium‐Ion Battery (Adv. Energy Mater. 18/2016)
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1000.
Yoshinari Moriguchi Kentaro Uchiyama Saneyoshi Ueno Tokuko Ujino-Ihara Asako Matsumoto Junji Iwai Daisuke Miyajima Maki Saito Masaya Sato Yoshihiko Tsumura 《Tree Genetics & Genomes》2016,12(3):57
Cryptomeria japonica pollinosis is one of the most serious allergic diseases in Japan; this is a social problem because C. japonica is the most important Japanese forestry species. In order to reduce the amount of pollen dispersed, breeding programs using trees with male-sterile genes have been implemented. High-density linkage maps with stable ordering of markers facilitate the localization of male-sterile genes and the construction of partial linkage maps around them in order to develop markers for use in marker-assisted selection. In this study, a high-density linkage map for C. japonica with 2560 markers was constructed. The observed map length was 1266.2 cM and the mean distance between adjacent markers was 0.49 cM. Using information from this high-density map, we newly located two male-sterile genes (ms3 and ms4) on the first and fourth linkage groups, respectively, and constructed partial linkage maps around these loci. We also constructed new partial linkage maps around the ms1 and ms2 loci using additional SNP markers. The closest markers to the ms1, ms2, ms3, and ms4 male-sterile loci were estSNP04188 (1.8 cM), estSNP00695 (7.0 cM), gSNP05415 (3.1 cM), and estSNP01408 (7.0 cM) respectively. These results allowed us to develop SNP markers tightly linked to the male sterile genes for use in MAS; this will accelerate the future isolation of these genes by map-based cloning approaches. 相似文献