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951.
952.
The reliability and durability of lithium‐ion capacitors (LICs) are severely hindered by the kinetic imbalance between capacitive and Faradaic electrodes. Efficient charge storage in LICs is still a huge challenge, particularly for thick electrodes with high mass loading, fast charge delivery, and harsh working conditions. Here, a unique thermally durable, stable LIC with high energy density from all‐inorganic hydroxyapatite nanowire (HAP NW)‐enabled electrodes and separators is reported. Namely, the LIC device is designed and constructed with the electron/ion dual highly conductive and fire‐resistant composite Li4Ti5O12‐based anode and activated carbon‐based cathode, together with a thermal‐tolerant HAP NW separator. Despite the thick‐electrode configuration, the as‐fabricated all HAP NW‐enabled LIC exhibits much enhanced electrochemical kinetics and performance, especially at high current rates and temperatures. Long cycling lifetime and state‐of‐the‐art areal energy density (1.58 mWh cm?2) at a high mass loading of 30 mg cm?2 are achieved. Benefiting from the excellent fire resistance of HAP NWs, such an unusual LIC exhibits high thermal durability and can work over a wide range of temperatures from room temperature to 150 °C. Taking full advantage of synergistic configuration design, this work sets the stage for designing advanced LICs beyond the research of active materials. 相似文献
953.
Paraoxonase is an HDL-associated enzyme that plays a preventive role against oxidative stress, which is thought to contribute
to cancer development. PON1 activity varies widely among individuals, which is in part related to two common nonsynonymous
polymorphisms in the PON1 gene (Q192R and L55M). The polymorphisms in PON1 have been implicated in cancer risk. However, results
from the studies to date have been conflicting. To clarify the association, a meta-analysis was performed for 7,073 cases
and 9,520 controls from 25 published case–control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used
to assess the strength of the association. Significant associations between PON1-L55M but not Q192R polymorphism and total
cancer were observed from all the comparisons. In stratified analyses, PON1-55M allele was a risk factor for breast cancer.
Similarly, increased risk was observed for prostate cancer (OR = 1.18, 95% CI: 1.01–1.36, P
heterogeneity = 0.260) and Caucasian population (OR = 1.18, 95% CI: 1.02–1.38, P
heterogeneity = 0.1) of the LM genotype, compared with the LL genotype. For PON1-Q192R polymorphism, PON1-192R allele was a decreased risk
factor for cancer in the Asian group (RR vs QQ: OR = 0.61, 95% CI: 0.38–0.98, P
heterogeneity = 0.268; QR vs QQ: OR = 0.71, 95% CI: 0.52–0.96, P
heterogeneity = 0.130; RR + QR vs QQ: OR = 0.71, 95% CI: 0.53–0.95, P
heterogeneity = 0.135). Although some modest bias could not be eliminated, this meta-analysis suggests that the PON1-55M allele is a risk factor for the development of cancer, in particular for breast cancer. Future studies with larger sample
sizes are warranted to further evaluate these associations. 相似文献
954.
Peng Wang Yongzhong Xing Zhikang Li Sibin Yu 《Molecular breeding : new strategies in plant improvement》2012,29(4):903-913
To facilitate marker-assisted transfer of desirable genes for improvement of yield traits, we used a set of backcross recombinant
inbred lines (BRIL) derived from two elite parental lines, ‘Zhenshan97’ and ‘93-11’, to resolve a quantitative trait loci
(QTL) cluster for heading date and yield-related traits in rice. Four main-effect QTL (qHD6.1, qHD6.2, qHD7, and qHD8) and four epistatic QTL affecting heading date in the BRIL were detected in two experimental trials. The major QTL (qHD8) was confirmed in three heterogeneous inbred families (HIF) that segregated for this target region, and narrowed down to
a 20-kb segment in a large HIF-derived population. qHD8 was found to interact with qHD7 and had a pleiotropic effect responsible for heading date and yield components. To test usability of the identified QTL in
rice improvement, we further developed near-isogenic lines (NIL) containing one or more target genes by marker-assisted transfer
of ‘93-11’ alleles at qHD8, qHD7, and qHD6.1, and the GS3 gene for grain size into ‘Zhenshan97’. The pyramid line NIL(qHD8 + GS3) had higher yield potential, longer grains, and a more suitable heading date than ‘Zhenshan97’. Comparison of the NIL showed
existence of epistasis between alleles at different loci and background effect on qHD8, which are very important for pyramiding of desirable alleles at the target QTL. These results will be particularly useful
not only to understand the genetic basis of yield-related traits but also to improve the efficiency of marker-assisted selection
for favorable loci in rice breeding programs. 相似文献
955.
Late-acting self-incompatibility in tea plant (<Emphasis Type="Italic">Camellia sinensis</Emphasis>)
The self-incompatibility of tea plant (Camellia sinensis (L.) O. Kuntze) was studied with the methods of aniline blue fluorescence assay and paraffin sections. The characteristics
of pollen tube elongation after hand pollination was analyzed in 4 tea cultivars, including ‘Keemenzhong’, ‘Longjing-changye’,
‘Fuding-dabaicha’ and ‘Yabukita’, under self-pollination and cross-pollination, respectively. Although there were some difference
among cultivars, pollen tubes elongated through the style and reach the ovary successfully at 48 h after pollination for both
cross- and self-pollen tubes in all the four cultivars of tea. Pollen tubes entered into the ovule micropyles, however, only
for cross-pollination, but not for self-pollination. Pollen tubes of selfing plants, failed in fertilizing, seemed have some
difficulties to enter the ovule. All of which indicated that the self-incompatibility of tea plant is a late-acting self-incompatibility
system (LSI) or an ovarian sterility (OS), in which the self incompatibility was due to none self pollen tube penetrating
into the ovule and no fertilization. 相似文献
956.
Ke-Jing Wang Xiang-Hua Li Tetsuro Yamashita Yoshihito Takahata 《Plant Systematics and Evolution》2012,298(1):1-7
The wild soybean (Glycine soja), which is the progenitor of cultivated soybean (Glycine max), is expected to offer more information about genetic variability and more useful mutants for evolutionary research and breeding
applications. Here, a total of 1,600 wild soybean samples from China were investigated for genetic variation with regard to
the soybean Kunitz trypsin inhibitor (SKTI). A new mutant SKTI, Tik, was identified. It was found to be a Tia-derived codominant allele caused by a transversion point mutation from C to G at nucleotide +171, leading to an alteration
of one codon (AAC → AAG) and a corresponding amino acid substitution (Asn → Lys) at the ninth residue. Upon examination of
this variant and others previously found in wild soybeans, it became clear that SKTI has undergone high-level evolutionary
differentiation. There were more abundant polymorphisms in the wild than in the cultivated soybean. 相似文献
957.
958.
Osmotic stress and endogenous hormone levels may have a role in shoot organogenesis, but a systematic study has not yet to
investigate the links. We evaluated the changes of the endogenous indole-3-acetic acid (IAA) and abscisic acid (ABA) levels
in rice (Oryza sativa L. cv. Tainan 5) callus during shoot organogenesis induced by exogenous plant growth regulator treatments or under osmotic
stress. Non-regenerable callus showed low levels of endogenous ABA and IAA, with no fluctuation in level during the period
evaluated. The addition of 100 μM ABA or 2 mM anthranilic acid (IAA precursor) into Murashige and Skoog basal induction medium
containing 10 μM 2,4-D enhanced the regeneration frequency slightly, to 5 and 35%, respectively, and their total cellular
ABA or IAA levels were increased significantly, correspondingly to the treatments. However, the regeneration frequency was
greatly increased to 80% after treatment with 0.6 M sorbitol or 100 μM ABA and 2 mM anthranilic acid combined. Both treatments
produced high levels of total cellular ABA and IAA at the callus stage, which was quickly decreased on the first day after
transfer to regeneration medium. Thus, osmotic stress-induced simultaneous accumulation of endogenous ABA and IAA is involved
in shoot regeneration in rice callus. 相似文献
959.
960.
Zhao X. Chen L. Ren Q. Wu Z. Fang S. Jiang Y. Chen Y. Zhong Y. Wang D. Wu J. Zhang G. 《Applied Biochemistry and Microbiology》2021,57(3):344-350
Applied Biochemistry and Microbiology - A pyridine-transforming strain P2 was isolated from sewage collected from Guangzhou oil stain field(China).According to the system analysis, it was... 相似文献