Synthesis of Piperidones from Benzyl Azides and Acetone

A new method for the synthesis of 2,2-dimethyl-6-substituted 4-piperidone was developed; two equivalents of acetone were annulated with N-unsubstituted imines in-situ generated from benzyl azides using a ruthenium catalyst in the presence of L-proline.X113Ysciescopu

Six SNPs and a TTG indel in sheep desmoglein 4 gene are in complete linkage disequilibrium

Desmoglein 4 (DSG4) plays an important role in the regulation of growth and differentiation of hair follicles in mammals. In this study, a 755 bp long segment of DSG4 was screened in 544 sheep sampled from nine Chinese indigenous breeds and two Western breeds using PCR-SSCP assay with three different pairs of primers. Two of the three fragments showed polymorphisms with genotypes defined as AA, AB, BB and BC, and DD, DE, and EE, respectively. Interestingly, polymorphisms in these two fragments were in strong linkage disequilibrium. Only three haplotypes were found, of which haplotype AD determined by alleles A and D was the major one in all breeds, while haplotype BE was only found in Chinese breeds that possess divergent frequencies ranging from 0.02 to 0.43; haplotype CD was very rare and present in only one Chinese sheep. Sequences of the three haplotypes showed seven single nucleotide polymorphisms (SNPs) and a TTG insertion/deletion (indel), leading to five amino acid substitutions and a glycine indel. Our study provides valuable genetic markers in evaluating the impact of the DSG4 gene on wool traits in sheep.Key words: Sheep, DSG4 gene, single-strand conformational polymorphism (SSCP), variation, linkage disequilibrium

Exogenous application of plant growth regulators increased the total flavonoid content in Taraxacum officinale Wigg

The effects of plant growth regulators (PGRs) were studied on growth, total flavonoid, gibberellins (GA) and salicylic acid (SA) contents of Taraxacum officinale (dandelion), a widely used medicinal plant in Korea. All the four PGRs used; gibberellic acid (GA3), kinetin (Kn), salicylic acid (SA) and ethephon (2- chloroethylphosphonic acid) were applied at the rates of 0.5 and 1.0 mM. GA3 markedly enhanced fresh shoot weight, while 0.5 mM of kinetin application significantly enhanced dry root mass as compared tocontrol. SA enhanced both shoot and root attributes, while ethephon decreased plant growth. Endogenous bioactive GA1 and GA4 content and SA content enhanced with the application of GA3, SA and kinetin, but declined with ethephon. The flavonoid content of dandelion significantly increased with SA treatment, but was not altered with the application of other PGRs. The current study demonstrated the favorable effect of GA3, kinetin and SA on growth, bioactive GAs, SA and flavonoid contents of dandelion. These investigations offered interesting information as PGRs were never tested for plant growth and development of dandelion. It also reports the presence of both early C-13 hydroxylation and non C-13 hydroxylation pathways of GA biosynthesis in dandelion for the first time

Novel and simple patterning process of quantum dots via transfer printing for active matrix qd-led

© 2020 SID. The next generation of a self-emitting display requires precise and stable patterning techniques to shape Red, Green, and Blue pixels using quantum dots. In this study, we propose the novel and simple transfer printing process for the active matrix QD-LEDs

Uterine selection of human embryos at implantation

Human embryos frequently harbor large-scale complex chromosomal errors that impede normal development. Affected embryos may fail to implant although many first breach the endometrial epithelium and embed in the decidualizing stroma before being rejected via mechanisms that are poorly understood. Here we show that developmentally impaired human embryos elicit an endoplasmic stress response in human decidual cells. A stress response was also evident upon in vivo exposure of mouse uteri to culture medium conditioned by low-quality human embryos. By contrast, signals emanating from developmentally competent embryos activated a focused gene network enriched in metabolic enzymes and implantation factors. We further show that trypsin, a serine protease released by pre-implantation embryos, elicits Ca2+ signaling in endometrial epithelial cells. Competent human embryos triggered short-lived oscillatory Ca2+ fluxes whereas low-quality embryos caused a heightened and prolonged Ca2+ response. Thus, distinct positive and negative mechanisms contribute to active selection of human embryos at implantation

Nodal quasiparticle meltdown in ultra-high resolution pump-probe angle-resolved photoemission

High-$T_c$ cuprate superconductors are characterized by a strong momentum-dependent anisotropy between the low energy excitations along the Brillouin zone diagonal (nodal direction) and those along the Brillouin zone face (antinodal direction). Most obvious is the d-wave superconducting gap, with the largest magnitude found in the antinodal direction and no gap in the nodal direction. Additionally, while antinodal quasiparticle excitations appear only below $T_c$, superconductivity is thought to be indifferent to nodal excitations as they are regarded robust and insensitive to $T_c$. Here we reveal an unexpected tie between nodal quasiparticles and superconductivity using high resolution time- and angle-resolved photoemission on optimally doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. We observe a suppression of the nodal quasiparticle spectral weight following pump laser excitation and measure its recovery dynamics. This suppression is dramatically enhanced in the superconducting state. These results reduce the nodal-antinodal dichotomy and challenge the conventional view of nodal excitation neutrality in superconductivity.Comment: 7 pages, 3 figure. To be published in Nature Physic

Smoking Cessation after Diagnosis of New-Onset Atrial Fibrillation and the Risk of Stroke and Death

Limited data are available regarding the impact of smoking cessation after atrial fibrillation (AF) diagnosis on clinical outcomes. Using the Korean National Health Insurance Service database, we included patients newly diagnosed with AF and categorized them into four groups as follows: (i) never smokers, (ii) ex-smokers, (iii) smoking cessation after AF diagnosis (“quitters”), and (iv) current smokers. The primary outcomes were incident ischemic stroke and all-cause death during follow-up. Fatal ischemic stroke and death from cerebrovascular events were evaluated as secondary outcomes. Among 97,637 patients (mean age, 61 years; mean CHA(2)DS(2)-VASc score, 2.3), 6.9% stopped smoking after AF diagnosis. The mean follow-up duration was 3.2 ± 2.0 years. After multivariable adjustment, quitters had lower risks of ischemic stroke (hazard ratio (HR), 0.702; 95% confidence interval (CI), 0.595–0.827) and all-cause death (HR, 0.842; 95% CI, 0.748–0.948) than current smokers. Quitters after AF diagnosis were associated with lower risks of fatal ischemic stroke (HR, 0.454; 95% CI, 0.287–0.718) and death from cerebrovascular events (HR, 0.664; 95% CI, 0.465–0.949) compared with current smokers. Quitting smoking may reduce the risk of ischemic stroke, the severity of ischemic stroke, and the incidence of cerebrovascular events in patients with new-onset AF

On CP Asymmetries in Two-, Three- and Four-Body D Decays

Indirect and direct CP violations have been established in K_L and B_d decays. They have been found in two-body decay channels -- with the exception of K_L to pi^+ pi^- e^+ e^- transitions. Evidence for direct CP asymmetry has just appeared in LHCb data on A_{CP}(D^0 to K^+ K^-) - A_{CP}(D^0 to pi^+ pi^-) with 3.5 sigma significance. Manifestations of New Dynamics (ND) can appear in CP asymmetries just below experimental bounds. We discuss D^{\pm}_{(s)}, D^0/\bar D^0 and D_L/D_S transitions to 2-, 3- and 4-body final states with a comment on predictions for inclusive vs. exclusive CP asymmetries. In particular we discuss T asymmetries in D to h_1 h_2 l^+ l^- in analogy with K_L to pi^+ pi^- e^+ e^- transitions due to interference between M1, internal bremsstrahlung and possible E1 amplitudes. Such an effect depends on the strength of CP violation originating from the ND -- as discussed here for Little Higgs Models with T parity and non-minimal Higgs sectors -- but also in the interferences between these amplitudes even in the Standard Model (SM). More general lessons can be learnt for T asymmetries in non-leptonic D decays like D to h_1h_2 h_3 h_4. Such manifestations of ND can be tested at LHCb and other Super-Flavour Factories like the projects at KEK near Tokyo and at Tor Vergata/Frascati near Rome.Comment: 27 pages, 6 figures. Revised with current results from LHCb and HFAG and further interpretation