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Background Breast cancer (BC), a very heterogeneous systemic disease, is the most frequently seen malignancy in women, especially in some developed countries or regions. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and Ki67 have been extensively used to predict the clinical outcome, but it is still a hotspot to search for more predictive prognostic markers. Ankyrin repeat and death domain containing 1A (ANKDD1A), which contains nine ankyrin repeats, has been discovered to play a role of tumor suppressor in glioblastoma multiforme (GBM). However, its role in BC remains unknown so far. Methods ANKDD1A expression and clinical information of BC were extracted from the TCGA dataset. Then, the ANKDD1A expression level was explored in BC from different perspectives, including clinical stage, molecular subtype, histology type and immune microenvironment. Afterwards, functional enrichment analysis of ANKDD1A co-expressed genes was carried out to estimate the role of ANKDD1A in BC, and the methylation status of ANKDD1A was evaluated by MEXPRESS. In addition, the correlation of ANKDD1A with immunocytes was explored, and survival analysis was carried out to evaluate the prognostic value of ANKDD1A in BC. Results ANKDD1A decreased in BC compared with the para-cancerous tissues. Additionally, ANKDD1A was up-regulated in early-stage BC, ER negative group, infiltrating lobular carcinoma, and the normal subtype in BC molecular subtypes. According to functional enrichment analysis, ANKDD1A co-expressed genes were mainly involved in the immune process. Also, our results revealed that ANKDD1A was tightly associated with T cells. Survival analysis suggested that, patients with higher ANKDD1A expression had more favorable prognosis than those with lower ANKDD1A expression. Conclusions ANKDD1A may serve as a critical gene in the pathogenesis of BC and the immune microenvironment of BC tissues.

Reported herein is the first example of electrochemical selenocyanation of imidazo[1,5-a]quinolines with KSeCN under metal catalyst- and chemical oxidant-free conditions. This sustainable strategy shows a broad scope and great compatibility with functional groups, and affords synthetically and biologically important selenocyanated imidazo[1,5-a]quinolines in good to excellent yields with cheap graphite and Ni plates as the electrodes. The gram-scale synthesis was also successfully conducted, which might demonstrate the potential value of this electrochemical protocol.

An electrochemical oxidative dehydrogenative C(sp3)–H amination reaction to construct trans-2,3-disubstituted aziridines is reported, which avoids using external oxidants and generates only hydroge...

Background: Fibrosis is an important histological change occurring in preeclamptic placentas, and might depends on the excess deposition of collagen I. However, the role of fibrotic placentas and collagen I in the pathogenesis of preeclampsia remains unclear. Methods: Collagen deposition and the expression of Collagen I in human placentas were analysed by Masson staining, Sirius red staining and western blotting. The role of collagen I in preeclampsia pathogenesis was studied in C57BL/6 mice.HTR-8/SVneo cells were used to investigate the mechanisms underlying the effects of collagen I in trophoblasts by transcriptome sequencing and pharmacological agonists. Finding: Human preeclamptic placentas exhibited a higher degree of fibrosis in stem villi and terminal villi than normal placentas, and were characterized by collagen I deposition. In vivo, a single injection of collagen I on gestational day 0.5 led to an increase in systolic pressure of pregnant mice from gestational day 4.5 -17.5, to a decrease in weight and number of viable embryos, and to enhanced placental collagen I expression, and degree of fibrosis compared with control mice. In vitro, collagen I attenuated the proliferation and invasion of HTR-8SV/neo cells. This effect could be reversed by treatment with agonist s of ERK and β-catenin. Transcriptome sequencing demonstrated that pathways related to cell proliferation and invasion were significantly downregulated in HTR-8/SVneo cells. Interpretation: Collagen I induced preeclampsia-like symptoms by suppressing the proliferation and invasion of trophoblasts through inhibition of the ERK phosphorylation and WNT/β-catenin signalling pathways. Funding: National Natural Science Foundation of China and Guangdong Province. Declaration of Interest: The authors declare no conflicts of interest. Ethical Approval: The collection of placentas was approved by the Ethics Committee of Nanfang Hospital（NFEC-2017-055）. All participants gave written consent prior to donating their placenta.

KOtBu-promoted oxidative dimerizations of 2-methylquinolines with molecular oxygen as the oxidant have been developed for the first time. The mild reaction conditions allow the homo- and cross-dimerizations of 2-methylquinolines to give functionalized 2-alkenyl bisquinolines in highly trans-selective manners.

A practical, electrochemical method is developed for the direct dehydrogenative lactonization of C(sp2/sp3)–H bonds under external oxidant- and metal-free conditions, delivering diverse lactones, including coumarin derivatives with excellent regioselectivity. The scalable nature of this newly developed electrochemical process was demonstrated on a 40 g scale following an operationally simple protocol. The remote lactonization of C(sp3)–H bonds would constitute an important synthetic advance toward electrochemical C–O bond formation.

We theoretically demonstrate the enhancement of subcycle interference patterns in photoelectron momentum distributions with a linearly polarized two-color field. Our results show that the ionization time of electron wave packets can be confined to one optical cycle in the two-color field. Then three kinds of dominant interference patterns can be observed simultaneously with one shot of lasers. Analysis of a semiclassical model identifies the two interference patterns in the photoelectron momentum distributions of P z > 0 ( P z is the momentum along the polarization direction of laser field) as two kinds of forward rescattering holographic patterns. In addition, we also introduce the transient electron density method to identify the main interference structures in the photoelectron momentum distributions of P z 0 , and find that the main interference structures in the photoelectron momentum distributions of P z 0 come from the intracycle interference.

The dynamic behavior of thermally-induced metal-insulator transition of V2O3 thin film on Si substrate grown by reactive magnetron sputtering was investigated by the terahertz time-domain spectroscopy. It was found that the THz absorption and optical conductivity of the thin films are temperature-dependent, and the THz amplitude modulation can reach as high as 74.7%. The complex THz optical conductivity in the metallic state of the V2O3 thin films can be well-fitted by the Drude-Smith model, which offer the insight into the electron transport dynamic during the metal-insulator transition of the thin film.

An electrochemical oxidative dehydrogenative C(sp

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The hydrotrifluoromethylation of benzyl-protected homoallylic alcohol and amine derivatives catalyzed by 2,4,5,6-tetra(9 H-carbazol-9-yl)isophthalonitrile (4CzIPN) was developed. This reaction delivered δ-fluoromethylated free alcohols and amines with in situ deprotection of benzyl protecting group under mild irradiation conditions. 4CzIPN was found to be a competent metal-free photoredox catalyst for activating several types of fluoromethylation reagents including CF3SO2Cl, Togni's reagent, and 2-bromo-2,2-difluoroacetate via oxidative quenching and also CF3SO2Na through reductive quenching to allow direct hydrotrifluoromethylation of simple alkenes and Michael acceptors.

We theoretically investigate the carrier-envelope-phase (CEP) effect of laser pulses in the generation of solid high-order harmonics under nonadiabatic conditions using the time-dependent density functional theory. It is found that the CEP dependence of solid harmonics is still complex even if the Keldysh parameter $\ensuremath{\gamma}$ remains unchanged. Further analysis shows that the multiphoton ionization still contributes to the generation of high-order harmonics for solids with inversion symmetry when the minimum band gap between the highest valence band and the lowest conduction band is equal to even multiples of the laser frequency. The relative contribution of tunneling ionization and multiphoton ionization to the harmonic generation is responsible for this complex CEP dependence.

Fine-tuning of multi-color emission characteristics of upconversion lanthanide-ion-doped nanocrystals is of high importance for 3-D color displays, multi-color bio-imaging, and multiplexed cellular labeling. Here, we report a strategy enabling crystal phase transition and morphology transformation between GdF3:Yb3+,Tm3+ and GdOF:Yb3+,Tm3+ nanocrystals for fine-tuning of upconversion multi-color emissions. By controlling the ratio between oleylamine (OM)/octadecene (ODE), the orthorhombic phase of rhombic nanoplates (GdF3:Yb3+,Tm3+) was transformed to the cubic phase of nanospheres (GdOF:Yb3+,Tm3+), along with their upconversion color change from blue to red. Broadband upconversion emission was observed from GdOF:Yb3+,Tm3+ nanocrystals at a high excitation power, which is expected to originate from oxygen defects. Multi-color upconversion nanocrystals providing broadband emission are expected to find their applications in broad band multi-color biomolecular imaging requiring a high imaging resolution.

An efficient and practical (hetero)benzylic sp3 C–H oxidation method has been developed. Notably, this user-friendly protocol employs inexpensive potassium tert-butoxide (KOtBu) as a promoter and proceeds under mild conditions using oxygen as the oxidant. A large variety of oxidation products were prepared in good to excellent yields. The utility of this “green” methodology was further demonstrated by the scale-up preparation of a biologically valued molecule.

A simple triphenylphosphine-ligated cobalt catalyst is reported for the direct ortho-C-H methylation and ethylation of aromatic, heteroaromatic, alkenyl, and even aliphatic carboxamides with inexpensive organoaluminum reagents in the presence of a cheap alkyl chloride as oxidant. This reaction shows monoselectivity in contrast with previously established C-H methylation methodologies.

A copper/iodine cocatalyzed decarboxylative cyclization of α-amino acids is described. Starting from the readily available amino acids and either 2-benzoylpyridines or 2-benzoylquinolines, 1,3-disubstituted imidazo[1,5-a]pyridines and 1,3-disubstituted imidazo[1,5-a]quinolines were prepared in excellent yields.

We investigate the limitations of the single-electron time-dependent Schr\"odinger equation (TDSE) in the studies of solid high-order harmonic generation (HHG). Two main differences are found by comparing the harmonic spectra calculated by TDSE and semiconductor Bloch equations (SBEs) in the same conditions. One is that the spectrum obtained from SBEs only contains clear odd harmonics, but that derived from TDSE consists of even and odd harmonics. The other is that the two approaches derive different linear dependence of cutoff energy on electric strength and wavelengths of laser fields. These discrepancies can be attributed to the single-active-electron approximation used in TDSE. Moreover, we find that the phase mismatching between the dipole interaction and the intrinsic dynamical phase of the system is responsible for the generation of even harmonics in the single-active-electron approximation. Finally, an approach is proposed to expand the applicable range of TDSE further. Our results demonstrate that many-body effects must be taken into account in solid HHG simulations, though the Coulomb interaction between electrons can be neglected in some cases.

We theoretically investigate the generation of elliptically polarized isolated attosecond pulses from He+ prepared in an initial 2p0 state with a linearly polarized two-color field. It is shown that the elliptically polarized broadband supercontinuum can be produced via controlling the acceleration step of high-order harmonic generation using a two-color field. Then elliptically polarized isolated attosecond pulses can be obtained by filtering the supercontinuum. In addition, we find that the ellipticity of attosecond pulses corresponding to the short trajectory is larger than that corresponding to the long trajectory for all the polarization directions of the driving field. Further analysis reveals that the influence of the Coulomb effect to the dynamics of the continuum electrons is responsible for the difference.

A copper(II)-catalyzed tandem reaction between pyridine ketone and benzylamine was developed by using clean O2 as an oxidant. This transformation proceeded via an efficient condensation-amination-oxidative dehydrogenation process, affording 1,3-diarylated imidazo[1,5-a]pyridines in excellent yields.

We report the highest compression reached in laboratory plasmas using eight laser beams, E$_{laser}$$\approx$12 kJ, $\tau_{laser}$=2 ns in third harmonic on a CD$_2$ target at the ShenGuang-II Upgrade (SGII-Up) facility in Shanghai, China. We estimate the deuterium density $\rho_D$= 2.0 $\pm$ 0.9 kg/cm$^{3}$, and the average kinetic energy of the plasma ions less than 1 keV. The highest reached areal density $\Lambda \rho_{D}$=4.8 $\pm$ 1.5 g/cm$^{2}$ was obtained from the measured ratio of the sequential ternary fusion reactions (dd$\rightarrow$t+p and t+d$\rightarrow$$\alpha$+n) and the two body reaction fusions (dd$\rightarrow$$^3$He+n). At such high densities, sequential ternary and also quaternary nuclear reactions become important as well (i.e. n(14.1 MeV) + $^{12}$C $\rightarrow$ n'+$^{12}$C* etc.) resulting in a shift of the neutron (and proton) kinetic energies from their birth values. The Down Scatter Ratio (DSR-quaternary nuclear reactions) method, i.e. the ratio of the 10-12MeV neutrons divided by the total number of 14.1MeV neutrons produced, confirms the high densities reported above. The estimated lifetime of the highly compressed plasma is 52 $\pm$ 9 ps, much smaller than the lasers pulse duration., Comment: 6 pages, 5 figures, submit version

A practical, electrochemical method is developed for the direct dehydrogenative lactonization of C(sp

DNA nanotechnology offers a massively parallel process to build innovative nanomaterials from the bottom up with excellent structural programmability and functional tunability. So far most of the successes have been restricted to gold nanoparticles (AuNPs) based on an earlier breakthrough in controlling the number (valence) of DNA ligands on an AuNP. However, attempts to incorporate non-gold metal materials have met various difficulties. To address this challenge, we herein develop a method to achieve reliable DNA-conjugations and gel electrophoretic valence separations of Au@Ag and Au@Pd core–shell nanoparticles. The existence of a gold core allows us to control the structure, composition, and colloidal properties of the nanoparticles, which is critical to achieving compatibility with gel electrophoresis. The resulting bionanoconjugates with strictly defined DNA valences function very well in DNA-programmable nanoassembly towards various possible applications in the future.

An efficient and practical (hetero)benzylic sp

A copper/iodine cocatalyzed decarboxylative cyclization of α-amino acids is described. Starting from the readily available amino acids and either 2-benzoylpyridines or 2-benzoylquinolines, 1,3-disubstituted imidazo[1,5-a]pyridines and 1,3-disubstituted imidazo[1,5-a]quinolines were prepared in excellent yields.

The high-order harmonic generation of the HD molecule is studied in non-Born-Oppenheimer approximation. It is found that there are only the odd harmonics in the harmonic spectrum of the HD molecule though the generation of even harmonics is possible in principle. Theoretical analysis [T. Kreibich et al., Phys. Rev. Lett. 87, 103901 (2001)] reveals that the nuclear dipole moment can contribute to the generation of the even harmonics, but the acceleration of the nucleus is about three orders of magnitude less than that of the electron. Hence, the even harmonics cannot be observed in the harmonic spectrum of the HD molecule.

The past years have witnessed a rapid development of DNA nanotechnology in nanomaterials science with a central focus on programmable material construction on the nanoscale. An efficient method is therefore highly desirable (but challenging) for analytical/preparative purification of DNA-conjugated nano-objects and their DNA-assemblies. In this regard, agarose gel electrophoresis, a traditional technique that has been invented for biomacromolecule separation, has found many innovative uses. This includes shape, size, charge, and ligand-valence separations of nanoparticle building blocks as well as monitoring a self-assembly process towards product identification and purification.

The development of highly active, cheap and robust oxygen reduction reaction (ORR) electrocatalysts to replace precious metal platinum is extremely urgent and challenging for renewable energy devices. Herein we report a novel, green and especially facile hydrogel strategy to construct N and B co-doped nanocarbon embedded with Co-based nanoparticles as an efficient non-precious ORR catalyst. The agarose hydrogel provides a general host matrix to achieve a homogeneous distribution of key precursory components including cobalt (II) acetate and buffer salts, which, upon freeze-drying and carbonization, produces the highly active ORR catalyst. The gel buffer containing Tris base, boric acid and ethylenediaminetetraacetic acid, commonly adopted for pH and ionic strength control, plays distinctively different roles here. These include a green precursor for N- and B-doping, a salt porogen and a Co2+ chelating agent, all contributing to the excellent ORR activity. This hydrogel-based process is potentially generalizable for many other catalytic materials.

We theoretically investigate the nonadiabatic spectral redshift of high-order harmonics with the help of a VUV pulse. It is found that the nonadiabatic spectral redshift of high-order harmonics can be observed when a weak VUV pulse is properly added in the falling part of the fundamental laser due to the nonadiabatic response of the dipole to rapid change of laser intensity. Further time-frequency analysis shows that the high-order harmonics are mainly generated in the falling part of the fundamental pulse. This is because the VUV pulse enhances the ionization in the falling part of the fundamental pulse by the 1s-2p transition of $\text{H}{e}^{+}$. In addition, this scheme is also used to observe the nonadiabatic spectral blueshift of high-order harmonics by changing the time delay between the fundamental laser and the VUV pulse.

An efficient Cu(II)-catalyzed oxidative amination of sp3 C—H bonds using air as the terminal oxidant is presented.

Strong coupling between nanoparticles is critical for facilitating charge and energy transfers. Despite the great success of DNA-programmable nanoparticle assemblies, the very weak interparticle coupling represents a key barrier to various applications. Here, an extremely simple, fast, and highly efficient process combining DNA-programming and molecular/ionic bonding is developed to address this challenge, which exhibits a seamless fusion with DNA nanotechnology.

DNA nanotechnology makes use of DNA strands to build highly engineerable supramolecular structures from the bottom-up. Such a research field has been experiencing a fruitful development during the past decades. In materials science, an ambitious goal is to obtain materials with designable structures and predictable functions based on a suitable synthetic strategy. The rapid growth and expansion of the area of DNA nanotechnology have provided a useful technological platform suitable to demonstrate DNA’s unique roles in nanomaterials science. Although nanoparticle-based materials have been employed for controllable DNA conjugation and DNA-programmable self-assembly, some challenges still exist. In this chapter, we try to highlight the latest developments in DNA-directed nanophase materials, including new strategies for DNA decoration of gold and carbon-based nanomaterials, DNA origami-based nanoassembly templates, and DNA-conjugated non-gold nanoparticles with specifiable bonding valences, in response to the challenges we are currently facing.

Photoelectron angular momentum distribution of Hesup+/supdriven by a few-cycle laser is investigated numerically. We simultaneously observe two dominant interference patterns with one shot of lasers by solving the 3D time-dependent Schrodinger equation. Analysis of a semiclassical model identifies these two interference patterns as two types of photoelectron holography. The interference pattern with Psubz/sub0 is a type of forward rescattering holography, which comes from the interference between direct (reference) and rescattered (signal) forward electrons ionized in the same quarter-cycle. The interference pattern with Psubz/sub0 is a type of backward rescattering holography, which comes from the interference between a direct electron ionized in the third quarter-cycle and rescattered backward electron ionized in the first quarter-cycle. Moreover, we propose a method to distinguish this backward rescattering holography and intracycle interference patterns of direct electrons.