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The study of high-order harmonic generation (HHG) in confined quantum systems is essential for developing a comprehensive physical description of harmonic generation from atoms to bulk solids. Using the time-dependent density-functional theory, we demonstrate how the symmetry of the system modulates the generation of high-order harmonic in fullerene C60 molecules along different orthogonal directions, as well as the effects of amplitude and photon energy of a linearly polarized laser on high-order harmonics generation. We found that the generation of high-order harmonics perpendicular to the laser polarization direction (LPD) is related to the symmetry of molecules along the LPD and the symmetry of molecules perpendicular to the LPD. Within a certain parameter range, the cut-off energy is linearly proportional to the laser amplitude and the laser photon energy. [ABSTRACT FROM AUTHOR]

Previous studies have found that pure even harmonics are generated from oriented CO molecules in linearly polarized laser fields. In this work, we demonstrate multi-directions pure even harmonic simultaneous generation from planar molecules in linearly polarized laser fields using the time-dependent density-functional theory. The analysis reveals that pure even harmonic generation depends on the special symmetry of the planar molecule. In the linearly polarized laser field, it is found that only when the planar molecules have reflective symmetry direction and the molecules perpendicular to the reflective symmetry direction do not have reflection symmetry can the planar molecules generate pure even harmonics along such reflective symmetry direction. When the laser polarization is perpendicular to the planar molecule, if the molecule has several these directions of such reflection symmetry, pure even harmonics will be simultaneously generated along these symmetrical directions. Moreover, when the laser polarization is along the molecular plane and perpendicular to the direction of one such reflection symmetry, even harmonic is also generated along this reflection symmetry direction, whereas odd harmonic is generated along the direction of laser polarization. The phenomenon exists in all polyatomic planar molecules with such reflection symmetry. [ABSTRACT FROM AUTHOR]

Myeloid cells play an important role in a wide variety of cardiovascular disorders, including both ischemic and non-ischemic cardiomyopathies. Neuregulin-1 (NRG-1)/ErbB signaling has recently emerged as an important factor contributing to the control of inflammatory activation of myeloid cells after an ischemic injury. However, the role of ErbB signaling in myeloid cells in non-ischemic cardiomyopathy is not fully understood. This study investigated the role of ErbB3 receptors in the regulation of early adaptive response using a mouse model of transverse aortic constriction (TAC) for non-ischemic cardiomyopathy. TAC surgery was performed in groups of age- and sex-matched myeloid cell-specific ErbB3-deficient mice (ErbB3MyeKO) and control animals (ErbB3MyeWT). The number of cardiac CD45 immune cells, CD11b myeloid cells, Ly6G neutrophils, and Ly6C monocytes was determined using flow cytometric analysis. Five days after TAC, survival was dramatically reduced in male but not female ErbB3MyeKO mice or control animals. The examination of lung weight to body weight ratio suggested that acute pulmonary edema was present in ErbB3MyeKO male mice after TAC. To determine the cellular and molecular mechanisms involved in the increased mortality in ErbB3MyeKO male mice, cardiac cell populations were examined at day 3 post-TAC using flow cytometry. Myeloid cells accumulated in control but not in ErbB3MyeKO male mouse hearts. This was accompanied by increased proliferation of Sca-1 positive non-immune cells (endothelial cells and fibroblasts) in control but not ErbB3MyeKO male mice. No significant differences in intramyocardial accumulation of myeloid cells or proliferation of Sca-1 cells were found between the groups of ErbB3MyeKO and ErbB3MyeWT female mice. An antibody-based protein array analysis revealed that IGF-1 expression was significantly downregulated only in ErbB3MyeKO mice hearts compared to control animals after TAC. Our data demonstrate the crucial role of myeloid cell-specific ErbB3 signaling in the cardiac accumulation of myeloid cells, which contributes to the activation of cardiac endothelial cells and fibroblasts and development of an early adaptive response to cardiac pressure overload in male mice. [Display omitted] • The level of ErbB3 cell surface expression is higher on cardiac myeloid cells compared to cells in the blood and spleen • Transverse aortic constriction induced rapid, within three days after surgery, accumulation of myeloid cells in the heart • Genetic ablation of ErbB3 in myeloid cells resulted in the development of acute heart failure in male but not female mice • ErbB3 deletion was associated with reduced accumulation of myeloid cells in the hearts of male but not female mice • NRG-1, an ErbB receptor ligand, induced migration in myeloid cells from control animals but not from mice with ErbB3 deletion [ABSTRACT FROM AUTHOR]

The article offers information on crop tree release (CTR) has a beneficial effect on forest environments and structures by changing forest light, heat, and water. Topics include the impact of CTR on underground biodiversity remains unclear, and the results showed that CTR increased the density of soil nematodes (P < 0.05), the number of omnivore–predator nematodes (P < 0.05), and the diversity (H0) of nematodes (P < 0.05) and enriched the food web structure of soil nematodes.

Plasmon resonances and the plasmon-induced field enhancement (FE) in sodium nanoring dimers are investigated by time-dependent density functional theory. For larger separations, the optical absorption, the induced charge response and the frequency dependent current demonstrate that there are two capacitive coupling plasmon modes. One feature of FE is that, in the surface region of the nanoring, it has a very large maximum. Another feature of FE is that, along the perpendicular bisector of the line segment joining the two nanoring center points in the middle region of the nanoring dimers, it has maxima. With the decrease of the gap distance, because of the electrons tunneling across the dimer junction and screening, collective excitation modes are changed, and the charge transfer plasmon modes emerge in the nanoring dimers. FE induced by any plasmon modes decreases in the gap region. Moreover, corresponding to different gap distances, the high-energy plasmon resonance peak almost does not shift, because this plasmon mode is mainly the collective excitation as a result of interactions among degenerate individual electronic states. [ABSTRACT FROM AUTHOR]

In linear hydrogen atomic chains, plasmon resonances and plasmon-induced charge transport are studied by time-dependent density functional theory. For the large linear chain, it is a general phenomenon that, in the longitudinal excitation, there are high-energy resonances and a large low-energy resonance. The energy of the large low-energy resonance conforms to the results calculated by the classical Drude model. In order to explain the formation mechanism of the high-energy resonances, we present a simple harmonic oscillator model. This model may reasonably account for the relationship between low-energy and high-energy resonances, and has a certain degree of universality. As the interatomic distance decreases, the current shows a gradual transition from insulator to metal. The current enhancement mainly depends on the local field enhancement associated with plasmon excitation, and the enhanced electron delocalization effect as a result of the decrease of the interatomic distance. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In sodium nanoring dimers, plasmon resonances and the plasmon-induced field enhancement are investigated by time-dependent density functional theory. The optical absorption, the induced charge response, and the frequency dependent current demonstrate that the main plasmon resonance modes are the charge transfer plasmon mode and the bonding dimer plasmon mode (BDP). Moreover, there are also two small hybridized plasmon modes. The induced field enhancement of each spatial region depends on the gap distance and the plasmon mode. For the narrow gap, the field enhancement at different positions of the straight line segments between two nanorings is almost uniformly distributed. However, for large separations, along the axial direction, the field enhancement gradually decreases in the region within the radius of the sodium atom. Then, the change of the field enhancement is nonlinear. For different plasmon modes, there is a different number of field enhancement extrema. The largest extreme value is located in the middle region. These findings are expected to play an important role in designing plasmonic nanostructures for practical applications that require coupled metallic nanoparticles with enhanced electric fields. [ABSTRACT FROM AUTHOR]

In recent years, the lead-free double perovskite Cs2AgBiBr6 has emerged as an appealing alternative to lead-based perovskites due to its nontoxicity and long-term stability. In this study, we employed methyl acetate as an antisolvent and prepared high-quality Cs2AgBiBr6 films by a facile one-step spin-coating method. The prepared films exhibited excellent crystallinity with densely packed crystal grains. The root mean square roughness and average roughness of the obtained Cs2AgBiBr6 perovskite films were 6.69 and 5.43 nm, respectively. Furthermore, the memory device based on the Cs2AgBiBr6 perovskite films exhibited uniform and repeatable bipolar resistive switching performance with an ON/OFF ratio of 15, an endurance of 80 cycles, and a retention time of 104 s. This work showcases a simple and convenient one-step spin-coating method for depositing high-quality Cs2AgBiBr6 thin films while highlighting their potential application in resistive switching memories based on lead-free double perovskites. [ABSTRACT FROM AUTHOR]

The collectivity of the electronic motion in graphene nanostructures is studied by time-dependent density functional theory (TDDFT). Compared with the plasmon in the homogeneous graphene, the plasmon in the graphene nanostructure has some different properties due to the effect of the size and the all dimensional confinement. In lower-energy resonance zone, spectral band is greatly broadening, even extending to the near-infrared spectral area, and the photoabsorption strength line splits. The absorption spectrum also depends on the edge configuration of the graphene nanostructure. The armchair-edge and the zigzag-edge play different roles in the absorption spectrum. Moreover, our results also demonstrate that most low-energy resonances are localized in the boundary region. [ABSTRACT FROM AUTHOR]

Recently, zero-dimensional (0D) lead-free Cs3Cu2I5 materials have become one of the most attractive research hotspots in the optoelectronic field owing to their simple preparation method and long-term air stability. However, the photoluminescence quantum yield (PLQY) of the blue luminescence of Cs3Cu2I5 still lags behind those of the green and red luminescence of lead halide perovskites. Herein, 0D lead-free Cs3Cu2I5 films modulated by hydroiodic acid (HI) with a high PLQY of blue luminescence are addressed. The results show that the particle size of the Cs3Cu2I5 films decreases as the added amount of HI increases, from 223.3 (without HI) to 200.7 nm (with 0.076 mmol HI). The Cs3Cu2I5 films with 0.038 mmol HI display the lowest root-mean-square roughness of 14.7 nm. Moreover, the as-prepared films all exhibit blue luminescence at 445 nm, and the PLQY of Cs3Cu2I5 films reaches 85.3% when 0.038 mmol HI is added. Most importantly, the obtained films demonstrate long-term air stability under an ambient atmosphere, and the crystal structure and PLQY of Cs3Cu2I5 films have no obvious variation after 150 days. This air-stable lead-free blue luminescence with high PLQY provides a new strategy to promote the blue luminescence optical property of halide perovskite materials. [ABSTRACT FROM AUTHOR]

As a primary active ingredient of safflor yellow, hydroxysafflor yellow A (HSYA) exhibits notable antioxidative and neuroprotective effects. The aim of the present study was to investigate the protective effects of HSYA in mesenchymal stem cells (MSCs) exposed to hypoxia (5% O2) and serum deprivation (H/SD), and to explore the mechanisms underlying HSYA-mediated protection. Under H/SD conditions, HSYA was applied to protect MSCs against injury. Cell viability, proliferation, apoptosis and reactive oxygen species (ROS) levels were determined using an 5-ethynyl-2'-deoxyuridine assay, MTT assay, Hoechst 33342/propidium iodide and 2',7'-dichlorodihydrofluorescein diacetate staining, respectively. The results revealed that 160 mg/l HSYA significantly reduced apoptosis and ROS levels compared with the H/SD group; however, HSYA demonstrated minimal effects on cell proliferation. A western blot assay demonstrated that HSYA reduced cleaved caspase-3 expression and cytC release from the mitochondria to the cytoplasm when compared with the H/SD group. In addition, western blotting and RT-qPCR analyses revealed that HSYA treatment significantly increased the expression of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). In conclusion, the results of the current study demonstrated that HSYA exerts protective effects against H/SD-induced apoptosis in MSCs potentially via activation of the HIF-1α/VEGF signaling pathway and stabilization of the mitochondrial membrane. [ABSTRACT FROM AUTHOR]

Municipal solid waste incineration (MSWI) fly ash is a by-product of garbage incineration power generation, and its disposal is currently a world problem because it contains over standard heavy metals. This research aims to solidify the heavy metals in MSWI fly ash and make it to be utilizable construction materials under the guidance of intermediate-calcium cementitious materials (ICCM), and meanwhile figure out the solidification and hydration mechanism. The hydration characteristics of ICCM were characterized by XRD, FTIR, 29 Si MAS-NMR and SEM techniques, and the environmental properties are investigated by TCLP and EPMA. The results indicate that the optimal ratio of (CaO + MgO)/(SiO 2  + Al 2 O 3 ) for ICCM is at the range of 0.76–0.88. The compressive strengths of ICCM reach the 42.5R normal Portland cement level, and the leaching concentrations of heavy metals meet the Chinese integrated wastewater discharge standard GB 8978-1996. As predominant hydration products, ettringite, hydrocalumite and amorphous C-S-H gel are principally responsible for the strength development of ICCM, and the (Ca + Mg)/(Si + Al) ratio at 0.88 has the best polymerized structure. The heavy metals are well solidified through combining with the C-S-H gel or absorbed in the hydration pastes. This paper provides an effective solution to use the MSWI fly ash in building material. [ABSTRACT FROM AUTHOR]

Mutations in TGF-β-activated kinase 1 binding protein 2 (TAB2) have been implicated in the pathogenesis of dilated cardiomyopathy and/or congenital heart disease in humans, but the underlying mechanisms are currently unknown. Here, we identified an indispensable role for TAB2 in regulating myocardial homeostasis and remodeling by suppressing receptor-interacting protein kinase 1 (RIPK1) activation and RIPK1-dependent apoptosis and necroptosis. Cardiomyocyte-specific deletion of Tab2 in mice triggered dilated cardiomyopathy with massive apoptotic and necroptotic cell death. Moreover, Tab2-deficient mice were also predisposed to myocardial injury and adverse remodeling after pathological stress. In cardiomyocytes, deletion of TAB2 but not its close homolog TAB3 promoted TNF-α-induced apoptosis and necroptosis, which was rescued by forced activation of TAK1 or inhibition of RIPK1 kinase activity. Mechanistically, TAB2 critically mediates RIPK1 phosphorylation at Ser321 via a TAK1-dependent mechanism, which prevents RIPK1 kinase activation and the formation of RIPK1-FADD-caspase-8 apoptotic complex or RIPK1-RIPK3 necroptotic complex. Strikingly, genetic inactivation of RIPK1 with Ripk1-K45A knockin effectively rescued cardiac remodeling and dysfunction in Tab2-deficient mice. Together, these data demonstrated that TAB2 is a key regulator of myocardial homeostasis and remodeling by suppressing RIPK1-dependent apoptosis and necroptosis. Our results also suggest that targeting RIPK1-mediated cell death signaling may represent a promising therapeutic strategy for TAB2 deficiency-induced dilated cardiomyopathy. [ABSTRACT FROM AUTHOR]

The forest gap crucially influences forest environments, but its effects on local fungal community assembly are not fully understood. In this study, the fungal community in a weeping cypress forest was investigated as a function of forest gap locations based on forest clearing, using amplicon sequencing of the ITS2 region. The results showed that the fungal community significantly varied with the variations in soil properties related to gap location. Deterministic processes played pivotal roles in fungal community assembly, which was mainly driven by the temperature, moisture, available nitrogen, and microbial carbon in soil. Beta diversity of the fungal community increased from the gap center to the closed canopy. The relative abundances of dominant orders such as Microascales, Sordariales, and Chaetothyriales regularly varied as a function of gap location, and they were potential indicators for different gap locations. Based on network analysis, gap locations caused distinct co-occurrence patterns of fungal communities. This study shed light on the roles of forest gaps in the assembly of local fungal communities and provided additional strategies to manage forest ecosystems. [ABSTRACT FROM AUTHOR]

Background: Programmed cell death, including apoptosis, mitochondria-mediated necrosis, and necroptosis, is critically involved in ischemic cardiac injury, pathological cardiac remodeling, and heart failure progression. Whereas apoptosis and mitochondria-mediated necrosis signaling is well established, the regulatory mechanisms of necroptosis and its significance in the pathogenesis of heart failure remain elusive.Methods: We examined the role of tumor necrosis factor receptor-associated factor 2 (Traf2) in regulating myocardial necroptosis and remodeling using genetic mouse models. We also performed molecular and cellular biology studies to elucidate the mechanisms by which Traf2 regulates necroptosis signaling.Results: We identified a critical role for Traf2 in myocardial survival and homeostasis by suppressing necroptosis. Cardiac-specific deletion of Traf2 in mice triggered necroptotic cardiac cell death, pathological remodeling, and heart failure. Plasma tumor necrosis factor α level was significantly elevated in Traf2-deficient mice, and genetic ablation of TNFR1 largely abrogated pathological cardiac remodeling and dysfunction associated with Traf2 deletion. Mechanistically, Traf2 critically regulates receptor-interacting proteins 1 and 3 and mixed lineage kinase domain-like protein necroptotic signaling with the adaptor protein tumor necrosis factor receptor-associated protein with death domain as an upstream regulator and transforming growth factor β-activated kinase 1 as a downstream effector. It is important to note that genetic deletion of RIP3 largely rescued the cardiac phenotype triggered by Traf2 deletion, validating a critical role of necroptosis in regulating pathological remodeling and heart failure propensity.Conclusions: These results identify an important Traf2-mediated, NFκB-independent, prosurvival pathway in the heart by suppressing necroptotic signaling, which may serve as a new therapeutic target for pathological remodeling and heart failure. [ABSTRACT FROM AUTHOR]

Corrosion fatigue (CF) tests of 316LN weld metal were investigated in high-temperature water at different strain rates (0.0004–0.4%/s) under strain amplitude of 0.6%. Relationship between CF life and strain rate was proposed and environmental fatigue correction factor F en was also calculated. It was found that the γ/δ phase boundary was more susceptible to cracking at low strain rates and δ-ferrite worked as a barrier to retard the crack growth at high strain rates. Mechanisms of CF damage involving the effects of strain rate, hydrogen, δ-ferrite and residual strain on crack growth are also discussed. • Quantitative relation between fatigue life of 316LN weld metal and strain rate is purposed. • Effect of δ-ferrite changed with strain rate due to the interaction between localized deformation and environmental damage. • Mechanisms of CF damage involving the effects of hydrogen and residual strain on crack growth are proposed. [ABSTRACT FROM AUTHOR]

Recently, metal halide perovskite materials (CsPbX 3 , X = Cl, Br, and I) have attracted extensive attention for designing optoelectronic devices owing to their tuneable bandgap and high photoluminescence quantum yields (PLQYs). However, the corresponding study of CsPbX 3 perovskite quantum dots (QDs) with blue luminescence still lags far behind that of their red and green counterparts. Herein, we developed aluminium (Al3+) ion-doped CsPbBr 3 perovskite QDs through a supersaturated recrystallization synthetic approach at room temperature. The crystal structure and optical properties of the as-prepared QDs were systematically characterized. The results reveal that the particle size and lattice spacing of Al3+ ion-doped CsPbBr 3 QDs decrease as the Al/Pb molar ratio increases, which is attributed to the radius of Al3+ ions being much smaller than Pb2+ ions. A significant blueshift in the luminescence from 503 nm to 465 nm of Al3+ ion-doped QDs is observed as the Al/Pb molar ratio increases. Moreover, high colour purity (wide full-width at half-maximum of 83.3 meV) blue photoluminescence emission at 465 nm with a PLQY of 65.7% is achieved when the Al/Pb ratio reaches 1.0 in the Al3+ ion-doped CsPbBr 3 QDs, which shows good stability under ambient atmosphere. These as-prepared high colour purity blue luminescence Al3+ ion-doped CsPbBr 3 QDs show promising potential in blue optoelectronic fields. • A facile strategy to synthesize less-lead Al3+ ion-doped CsPbBr 3 QDs at room-temperature was proposed. • A significant blueshift from 503 nm to 465 nm of Al3+ ion-doped QDs is observed as the Al/Pb molar ratio increase. • The high colour purity blue photoluminescence emission at 465 nm with PLQY of 65.7% is achieved. [ABSTRACT FROM AUTHOR]

TAK1 (TGFβ-activated kinase-1) signaling is essential in regulating a number of important biological functions, including innate immunity, inflammatory response, cell growth and differentiation, and myocardial homeostasis. The precise role of TAK1 in the adult heart under pathological conditions remains largely unknown. Importantly, we observed that TAK1 is upregulated during compensatory hypertrophy but downregulated in end-stage heart failure. Here we generated transgenic mice with inducible expression of an active TAK1 mutant (TAK1ΔN) in the adult heart. TAK1ΔN transgenic mice developed greater cardiac hypertrophy compared with control mice after transverse aortic constriction (TAC), which was largely blocked by ablation of calcineurin Aβ. Expression of TAK1ΔN also promoted NFAT (nuclear factor of activated T-cells) transcriptional activity in luciferase reporter mice at baseline, which was further enhanced after TAC. Our results revealed that activation of TAK1 promoted adaptive cardiac hypertrophy through a cross-talk between calcineurin-NFAT and IKK-NFκB pathways. More significantly, adult-onset inducible expression of TAK1ΔN protected the myocardium from adverse remodeling and heart failure after myocardial infarction or long-term pressure overload, by preventing cardiac cell death and fibrosis. Mechanistically, TAK1 exerts its cardioprotective effect through activation of NFAT/NFκB, downregulation of Bnip3, and inhibition of cardiac cell death. [ABSTRACT FROM AUTHOR]