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The objective of this study was to screen non‐Saccharomyces yeast suitable for enhancing the aroma of Yinhong plum wine. Five non‐Saccharomyces yeasts with strong ester‐producing ability, namely, Wa3 (Wickerhamomyces anomalus), Hu12 (Hanseniaspora uvarum), Pk2A2, PkW2 and PkY2 (Pichia kluyveri), were selected from various naturally fermented fruit juices for molecular biological identification, analyses of physiological characteristics and tolerance and determination of their effects on the flavour of Yinhong plum wine. Analysis of brewing characteristics showed that they differed in their abilities of producing acetic acid, hydrogen sulfide, killer activity and tolerance. Among them, Wa3 showed the best tolerance to high concentrations of alcohol, sugar and SO2. Compared to the control Saccharomyces cerevisiae FX10, Yinhong plum wine fermented with non‐Saccharomyces yeast exhibited a decrease in alcohol content, while residual sugar, glycerol content and the types and quantities of volatile compounds all showed an increase. Among the fermented wines, PkY2 generated the highest content of ester compounds in the fermented wine, which was 5.66 times higher than that generated by the control. The compounds produced by PkY2 were closely related to various ethyl and acetate odour‐active compounds (odour‐active value >1), which could impart a rich floral and fruity aroma to Yinhong plum wine. Sensory analysis revealed that both floral and fruity aromas were significantly increased in Yinhong plum wine fermented by non‐Saccharomyces yeasts, with the highest scores of floral and fruity aromas for PkY2. In conclusion, a Pichia kluyveri strain, PkY2, with excellent brewing characteristics and potential for enhancing the aroma of Yinhong plum wine was identified. [ABSTRACT FROM AUTHOR]

Delayed wound healing is a major complication of diabetes, and is associated with impaired cellular functions. Current treatments are unsatisfactory. Based on the previous reports on microRNA expression in small extracellular vesicles (sEVs), miR‐17‐5p‐engineered sEVs (sEVs17‐OE) and encapsulated them in gelatin methacryloyl (GelMA) hydrogel for diabetic wounds treatment are fabricated. SEVs17‐OE are successfully fabricated with a 16‐fold increase in miR‐17‐5p expression. SEVs17‐OE inhibited senescence and promoted the proliferation, migration, and tube formation of high glucose‐induced human umbilical vein endothelial cells (HG‐HUVECs). Additionally, sEVs17‐OE also performs a promotive effect on high glucose‐induced human dermal fibroblasts (HG‐HDFs). Mechanism analysis showed the expressions of p21 and phosphatase and tensin homolog (PTEN), as the target genes of miR‐17‐5p, are downregulated significantly by sEVs17‐OE. Accordingly, the downstream genes and pathways of p21 and PTEN, are activated. Next, sEVs17‐OE are loaded in GelMA hydrogel to fabricate a novel bioactive wound dressing and to evaluate their effects on diabetic wound healing. Gel‐sEVs17‐OE effectively accelerated wound healing by promoting angiogenesis and collagen deposition. The cellular mechanism may be associated with local cell proliferation. Therefore, a novel bioactive wound dressing by loading sEVs17‐OE in GelMA hydrogel, offering an option for chronic wound management is successfully fabricated. [ABSTRACT FROM AUTHOR]

Ultrafast laser‐excitation of lithium niobate (LiNbO3) crystal has triggered numerous photonic applications through the structural transitions in LiNbO3. However, the explanations for ultrafast laser‐induced modification of LiNbO3 have remained phenomenological, lacking a convincing in‐depth understanding of the fundamental laser‐lattice interaction process. Based on ab initio simulations, it is demonstrated that photoexcited anharmonic phonons play a significant role in influencing the lattice structure of LiNbO3. Harnessing the real‐time time‐dependent density functional theory, it is revealed that the excitation of TO4 phonons via electric‐phonon coupling triggers displacement‐induced lattice oscillations during multiphoton ionization. These oscillations give rise to multistage structural strains, resulting in alterations of the refractive index. Significantly, these modifications exhibit sensitivity to the incident laser energy. Experimentally, using the waveguide technique and micro‐Raman spectroscopy, the correlation between local refractive index, lattice volume density, and phonon vibrational modes has been established, exhibiting good consistency with theoretical predictions. This work provides an effective means to understand the ultrafast excitation of phonons and relaxation processes of the lattice in dielectric crystals. [ABSTRACT FROM AUTHOR]

Enzyme‐prodrug therapies have shown unique advantages in efficiency, selectivity, and specificity of in vivo prodrug activation. However, precise spatiotemporal control of both the enzyme and its substrate at the target site, preservation of enzyme activity, and in situ substrate depletion due to low prodrug delivery efficiency continue to be great challenges. Here, we propose a novel core–shell reactor partitioning enzyme and prodrug by ZIF‐8, which integrates an enzyme with its substrate and increases the drug loading capacity (DLC) using a prodrug as the building ligand to form a Zn‐prodrug shell. Cytochrome P450 (CYP450) is immobilized in ZIF‐8, and the antitumor drug dacarbazine (DTIC) is coordinated and deposited in its outer layer with a high DLC of 43.6±0.8 %. With this configuration, a much higher prodrug conversion efficiency of CYP450 (36.5±1.5 %) and lower IC50 value (26.3±2.6 μg/mL) are measured for B16‐F10 cells with a higher NADPH concentration than those of L02 cells and HUVECs. With the tumor targeting ability of hyaluronic acid, this core–shell enzyme reactor shows a high tumor suppression rate of 96.6±1.9 % and provides a simple and versatile strategy for enabling in vivo biocatalysis to be more efficient, selective, and safer. [ABSTRACT FROM AUTHOR]

Dark excitons are fascinating for condensed matter physics, quantum information processing, and optoelectronics due to their long lifetimes. However, direct optical access to dark excitons is still challenging due to the violation of the spin selection rule. Here, a new scheme for the brightening of spin‐forbidden dark exciton in WS2 monolayers by creating artificial out‐of‐plane shear strain that induces an effective in‐plane pseudo‐magnetic field is proposed. To reveal dark excitons, low‐temperature magneto‐photoluminescence experiments on the strained WS2 monolayers are performed. It is found that the dark excitons appear at 59 meV below the bright ones and exhibit an asymmetric magnetic field dependence, which is in agreement with the model taking into account the effect of the out‐of‐plane shear strain on spin‐flip processes of exciton states. The fieldless scheme has great potential in the application of dark excitons for new quantum information processing devices. [ABSTRACT FROM AUTHOR]

Ferroptosis plays an essential role in the development of diabetes and its complications, suggesting potential therapeutic strategies targeting ferroptosis. Secretory autophagosomes (SAPs) carrying cytoplasmic cargoes have been recognized as novel nano‐warrior to defeat diseases. Here, it is hypothesized that SAPs derived from human umbilical vein endothelial cells (HUVECs) can restore the function of skin repair cells by inhibiting ferroptosis to promote diabetic wound healing. High glucose (HG)‐caused ferroptosis in human dermal fibroblasts (HDFs) is observed in vitro, which results in impaired cellular function. SAPs successfully inhibit ferroptosis in HG‐HDFs, thereby improving their proliferation and migration. Further research show that the inhibitory effect of SAPs on ferroptosis resulted from a decrease in endoplasmic reticulum (ER) stress‐regulated generation of free ferrous ions (Fe2+) in HG‐HDFs and an increase in exosome release to discharge free Fe2+ from HG‐HDFs. Additionally, SAPs promote the proliferation, migration, and tube formation of HG‐HUVECs. Then the SAPs are loaded into gelatin‐methacryloyl (GelMA) hydrogels to fabricate functional wound dressings. The results demonstrate the therapeutic effect of Gel‐SAPs on diabetic wounds by restoring the normal behavior of skin repair cells. These findings suggest a promising SAP‐based strategy for the treatment of ferroptosis‐associated diseases. [ABSTRACT FROM AUTHOR]

Recurrence is a challenge to survival after the initial treatment of esophageal squamous cell carcinoma (ESCC). But, its mechanism remains elusive and there are currently no biomarkers to predict postoperative recurrence. Here, the possibility of sterile alpha motif domain‐containing protein 9 (SAMD9) as a predictor of postoperative recurrence of ESCC is evaluated and the molecular mechanisms by which SAMD9 promotes ESCC recurrence are elucidated. The authors found that the high level of SAMD9 is correlated with postoperative recurrence and poor prognosis of ESCC. Overexpression of SAMD9 promotes tumor stemness, angiogenesis, and EMT, while downregulation of SAMD9 reduced these phenotypes. Mechanistically, it is found that SAMD9 stimulated ubiquitination‐mediated glycogen synthase kinase‐3 beta (GSK‐3β) degradation by interaction with myosin‐9 (MYH9) and TNF receptor‐associated factor 6 (TRAF6), which in turn activated Wnt/β‐catenin pathway. Further, the authors demonstrated that silencing SAMD9 inhibited lung metastasis and tumor formation in vivo. Finally, the authors found that silencing MYH9 or β‐catenin, or overexpressing GSK‐3β inhibited SAMD9‐stimulated ESCC cell stemness, EMT, angiogenesis, metastasis, and tumorigenicity. Together, the findings indicate that the SAMD9/MYH9/GSK3β/β‐catenin axis promotes ESCC postoperative recurrence and that SAMD9 is a crucial target for ESCC therapy. Additionally, SAMD9 has the potential as a predictor of postoperative recurrence in ESCC. [ABSTRACT FROM AUTHOR]

The local structure of a transition metal (TM) ion is a function of cation elements and valence states. More than that, in this work, by employing a trove of first‐principles data of TM oxides, the local structures of TM cations are statistically analyzed to extract detailed information about cation site preference, bond length, site structural distortion, and cation magnetization. It is found that cation radius alone poorly describes the local structure of a transition metal oxide, while the statistics of coordination number as well as the TMO bond length distribution, especially that of the 3d TMs, can provide comprehensive knowledge for understanding the behavior of TM elements. Based on these statistics, the interplay of site distortion due to the Jahn–Teller effect, cation site similarity, and a new set of ionic radii are all obtained to chart the "persona" of transition metal ions in solids. [ABSTRACT FROM AUTHOR]

Oxide interfaces provide a fertile ground for new forms of magnetic textures that arise from different symmetry constraints, proximity effects, and charge transfer. Here, a room‐temperature spin glass state stabilized in heterostructures of the ferromagnetic metallic oxide La2/3Sr1/3MnO3 (LSMO) and the layered Lan+1NinO3n+1 (L‐LNO) is reported. Electron energy loss spectra and depth‐profile X‐ray photoelectron spectroscopy reveal the interfacial electron transfer from Mn3+ to localized Ni3+ states. Density functional theory calculations indicate that charge transfer drives the enhancement of ferromagnetic exchange interaction in the nickelate, leading to the formation of local magnetic order. The room temperature spin‐glass state in this artificially engineered LSMO/L‐LNO bilayer structure affords opportunities for designing emergent topological spin textures and spintronic devices. [ABSTRACT FROM AUTHOR]

Let X$X$ be a compact complex space in Fujiki's Class C$\mathcal {C}$. We show that the group Aut(X)$\operatorname{Aut}(X)$ of all biholomorphic automorphisms of X$X$ has the Jordan property: there is a (Jordan) constant J=J(X)$J = J(X)$ such that any finite subgroup G⩽Aut(X)$G\leqslant \operatorname{Aut}(X)$ has an abelian subgroup H⩽G$H\leqslant G$ with the index [G:H]⩽J$[G:H]\leqslant J$. This extends, with a quite different method, the result of Prokhorov and Shramov for Moishezon threefolds. [ABSTRACT FROM AUTHOR]

Understanding hot carrier dynamics between plasmonic nanomaterials and its adsorbate is of great importance for plasmon‐enhanced photoelectronic processes such as photocatalysis, optical sensing and spectroscopic analysis. However, it is often challenging to identify specific dominant mechanisms for a given process because of the complex pathways and ultrafast interactive dynamics of the photoelectrons. Here, using CO2 reduction as an example, the underlying mechanisms of plasmon‐driven catalysis at the single‐molecule level using time‐dependent density functional theory calculations is clearly probed. The CO2 molecule adsorbed on two typical nanoclusters, Ag20 and Ag147, is photoreduced by optically excited plasmon, accompanied by the excitation of asymmetric stretching and bending modes of CO2. A nonlinear relationship has been identified between laser intensity and reaction rate, demonstrating a synergic interplay and transition from indirect hot‐electron transfer to direct charge transfer, enacted by strong localized surface plasmons. These findings offer new insights for CO2 photoreduction and for the design of effective pathways toward highly efficient plasmon‐mediated photocatalysis. [ABSTRACT FROM AUTHOR]

Recent evidence indicates that the abnormal differentiation of bone marrow‐derived mesenchymal stem cells (BMSCs) plays a pivotal role in the pathogenesis of osteoporosis. LncRNA SNHG1 has been found to be associated with the differentiation ability of BMSCs. In this study, we aimed to elucidate the role of lncRNA SNHG1 and its associated pathway on the differentiation of BMSCs in osteoporosis. Mice that underwent bilateral ovariectomy (OVX) were used as models of osteoporosis. Induced osteogenic or adipogenic differentiation was performed in mouse BMSCs. Compared to sham animals, lncRNA SNHG1 expression was upregulated in OVX mice. Also, the in vitro expression of SNHG1 was increased in adipogenic BMSCs but decreased in osteogenic BMSCs. Moreover, overexpression of SNHG1 enhanced the adipogenic capacity of BMSCs but inhibited their osteogenic capacity as determined by oil red O, alizarin red, and alkaline phosphatase staining, while silencing of SNHG1 led to the opposite results. LncRNA SNHG1 interacting with the RNA‐binding polypyrimidine tract‐binding protein 1 (PTBP1) promoted osteoprotegerin (Opg) methylation and suppressed Opg expression via mediating DNA methyltransferase (DNMT) 1. Furthermore, Opg was showed to regulate BMSC differentiation. Knockdown of SNHG1 decreased the expressions of adipogenic related genes but increased that of osteogenic related genes. However, the knockdown of Opg partially reversed those effects. In summary, lncRNA SNHG1 upregulated the expression of DNMT1 via interacting with PTBP1, resulting in Opg hypermethylation and decreased Opg expression, which in turn enhanced BMSC adipogenic differentiation and contributed to osteoporosis. [ABSTRACT FROM AUTHOR]

Charge transport in a single‐molecule junction is extraordinarily sensitive to both the internal electronic structure of a molecule and its microscopic environment. Two distinct conductance states of a prototype terphenyl molecule are observed, which correspond to the bistability of outer phenyl rings at each end. An azobenzene unit is intentionally introduced through atomically precise side‐functionalization at the central ring of the terphenyl, which is reversibly isomerized between trans and cis forms by either electric or optical stimuli. Both experiment and theory demonstrate that the azobenzene side‐group delicately modulates charge transport in the backbone via a single‐molecule stereoelectronic effect. We reveal that the dihedral angle between the central and outer phenyl ring, as well as the corresponding rotation barrier, is subtly controlled by isomerization, while the behaviors of the phenyl ring away from the azobenzene are hardly affected. This tunability offers a new route to precisely engineer multiconfigurational single‐molecule memories, switches, and sensors. [ABSTRACT FROM AUTHOR]

The past decades have witnessed the success of ground‐state density functional theory capturing static electronic properties of various materials. However, for time dependent processes especially those involving excited states, real‐time time‐dependent density functional theory (rt‐TDDFT) and advanced nonadiabatic algorithms are essential, especially for practical simulations of molecules and materials under the occurrence of ultrafast laser field. Here we summarize the recent progresses in developing rt‐TDDFT approaches within numerical atomic orbitals and planewave formalisms, as well as the efforts combining rt‐TDDFT and ring polymer molecular dynamics to take into account nuclear quantum effects in quantum electronic‐nuclear dynamic simulations. Typical applications of first‐principles dynamics of excited electronic states including high harmonic generation, charge density wave, photocatalytic water splitting, as well as quantum nuclear motions in ozone and graphene, are presented to demonstrate the features and advantages of these methods. The progresses in method developments and practical applications provide unprecedented insights into nonadiabatic dynamics of excited states in the Ehrenfest scheme and beyond, towards a comprehensive understanding of excited electronic structure, electron–phonon interactions, photoinduced charge transfer and chemical reactions, as well as quantum nuclear motions in excited states. This article is categorized under:Electronic Structure Theory > Ab Initio Electronic Structure MethodsElectronic Structure Theory > Density Functional TheoryMolecular and Statistical Mechanics > Molecular Dynamics and Monte‐Carlo Methods [ABSTRACT FROM AUTHOR]

Two types of nanosized niobium oxides and their composites, pseudohexagonal Nb2O5 (TT‐Nb2O5), monoclinic NbO2 (M‐NbO2), and the coexistence of TT‐Nb2O5 and M‐NbO2 (TT‐Nb2O5/M‐NbO2), are successfully synthesized through the urea‐metal chloride route, and they exhibit excellent catalytic activity and photovoltaic performance in dye‐sensitized solar cells (DSSCs). First‐principles density function theory (DFT) calculations show that their catalytic activity is significantly influenced by their intrinsic electronic structures and properties. The lone‐pair 4d1 electrons of Nb4+ in M‐NbO2 enhance the Nb–I interaction and promote electron transfer from the M‐NbO2 counter electrode (CE) to I, thus resulting in superior catalytic properties in M‐NbO2‐based DSSCs. In addition, the adsorption energy of I on the M‐NbO2 surface is in the optimal energy range of 0.3—1.2 eV, and the Fermi level of M‐NbO2 is 0.6 eV, which is higher than the I3− reduction reaction potential, and I3− can be spontaneously reduced to 3I−. Herein, a general strategy for understanding the electronic structures and catalytic activities of transition metal compounds as CE catalysts for DSSCs is provided. [ABSTRACT FROM AUTHOR]

Abstract: Two‐dimensional boron sheets (borophenes) have been successfully synthesized in experiments and are expected to exhibit intriguing transport properties. A comprehensive first‐principles study is reported of the intrinsic electrical resistivity of emerging borophene structures. The resistivity is highly dependent on different polymorphs and electron densities of borophene. Interestingly, a universal behavior of the intrinsic resistivity is well‐described using the Bloch–Grüneisen model. In contrast to graphene and conventional metals, the intrinsic resistivity of borophenes can be easily tuned by adjusting carrier densities, while the Bloch–Grüneisen temperature is nearly fixed at 100 K. This work suggests that monolayer boron can serve as intriguing platform for realizing tunable two‐dimensional electronic devices. [ABSTRACT FROM AUTHOR]

Effectively controlling photoinduced charge transport at the heterointerface is of crucial importance for improving the performance of photovoltaic devices. On the basis of an ipsilateral selective electron tunneling (ISET) mechanism, here this study investigates photoinduced charge transport and photovoltaic conversion at a simplified dye/single-layer graphene (SLG)/TiO2 ternary interface. With an amphiphilic Z907 molecule as the model dye, the photoexcited electrons in the dye can directly tunnel across SLG and be collected by the TiO2 layer with an efficiency of 96.23%, which guarantees a high-efficiency photoelectric conversion at the ISET-based heterointerface. More importantly, the intrinsic Schottky barrier and fast hole collection rate at the heterointerface lead to a high photovoltage, a large fill factor, and the good intense-light performance for photovoltaic conversion. Such an ISET-based heterointerface may offer a platform of designing and developing a novel class of photovoltaic devices with high efficiency. [ABSTRACT FROM AUTHOR]

Light‐induced interlayer ultrafast charge transfer in 2D heterostructures provides a new platform for optoelectronic and photovoltaic applications. The charge separation process is generally hypothesized to be dependent on the interlayer stackings and interactions, however, the quantitative characteristic and detailed mechanism remain elusive. Here, a systematical study on the interlayer charge transfer in model MoS2/WS2 bilayer system with variable stacking configurations by time‐dependent density functional theory methods is demonstrated. The results show that the slight change of interlayer geometry can significantly modulate the charge transfer time from 100 fs to 1 ps scale. Detailed analysis further reveals that the transfer rate in MoS2/WS2 bilayers is governed by the electronic coupling between specific interlayer states, rather than the interlayer distances, and follows a universal dependence on the state‐coupling strength. The results establish the interlayer stacking as an effective freedom to control ultrafast charge transfer dynamics in 2D heterostructures and facilitate their future applications in optoelectronics and light harvesting. [ABSTRACT FROM AUTHOR]

Plasmonic manipulation of light in metal/semiconductor heterostructures is a powerful tool that exploits extraordinary optical properties of metallic nanostructures to concentrate and control light at the nanometer scale. Here, recent progresses in the mechanism and strategies developed for the control of plasmon-induced optical field distribution, hot electron injection and energy transfer at the metal/semiconductor heterostructure interface are discussed. This is of crucial importance to the selection of matched materials, the design of optimized device architectures and the future development of efficient fabrication technologies for plasmon-enhanced photocatalytic and photovoltaic applications. [ABSTRACT FROM AUTHOR]

Superhydrophobic (SHO) surfaces have drawn great attention thanks to their theoretical significance and myriad applications in industry and everyday life. Current approaches to fabricate such surfaces require calcinating at high temperatures, tedious and time-consuming treatments, toxic chemicals, and/or processing with intricate instruments. Long-duration SHO surfaces are even more challenging due to material instability and easy contamination by organic pollutants in dry conditions. To overcome these difficulties we design a simple approach via self-supplying of low surface tension chemicals to nanoparticles to fabricate multifunctional SHO heterostructures. The method herein features room temperature, rapid processing, with environment-friendly raw materials. With multiple functions such as photocatalysis and transparency SHO surfaces further extend their lifetime and enable self-sustaining environment maintenance. [ABSTRACT FROM AUTHOR]

Mixed-valence manganites gain increasing attentions thanks to their extraordinary properties including half-metallicity and colossal magnetoresistive response, rendering them ideal candidate for oxide spintronics applications. Oxygen vacancies in oxides have been approved to be important functional defects and are effective to manipulating their multifunctional properties. To gain a deep insight into the roles of oxygen vacancies on regulating the atomic structure and electronic properties of the mixed-valence manganites, two high-quality epitaxial La2/3Sr1/3MnO3 films around a critical point (without/with oxygen vacancies) were designed and fabricated. From the experiments and theoretical calculations, it was found that the oxygen vacancies induce a weakening of Mn-O-Mn hybridized bond and an increase of concentration of Mn3+ ions, impair the double exchange between Mn3+ and Mn4+, and therefore lead to the transition from metal to insulator and the degraded magnetic properties. Our finding demonstrates a practical approach to tune the magnetic and transport properties of oxide thin films by precisely controlling the oxygen vacancies for high performance spintronics applications. [ABSTRACT FROM AUTHOR]

Thermoelectric devices can directly convert thermal energy to electricity or vice versa with the efficiency being determined by the materials' dimensionless figure of merit ( ZT). Since the revival of interests in the last decades, substantial achievements have been reached in search of high-performance thermoelectric materials, especially in the high temperature regime. In the near-room-temperature regime, MgAgSb-based materials are recently obtained with ZT ≈ 0.9 at 300 K and ≈1.4 at 525 K, as well as a record high energy conversion efficiency of 8.5%. However, the underlying mechanism responsible for the performance in this family of materials has been poorly understood. Here, based on structure refinements, scanning transmission electron microscopy (STEM), NMR experiments, and density function theory (DFT) calculations, unique silver and magnesium ion migrations in α-MgAg0.97Sb0.99 are disclosed. It is revealed that the local atomic disorders induced by concurrent ion migrations are the major origin of the low thermal conductivity and play an important role in the good ZT in MgAgSb-based materials. [ABSTRACT FROM AUTHOR]

A novel and facile activation process for electroless nickel deposition was developed. The semi-interpenetrating polymer network hydrogel biofilm was used to functionalize the inert poly(vinyl chloride) (PVC) surface, and then Cu nanoparticles, which can initial the subsequent electroless nickel deposition successfully seeded on the functionalized-PVC surface. The samples were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and transmission electron microscopy. The results show that the hydrogel film provided the PVC surface with amino groups and Cu nanoparticles of 20-50 nm in size could be functioned as the catalytic nuclei for the subsequent electroless metal deposition on PVC plastic. It can be concluded that the novel Cu activation was effective for the nickel deposition on PVC surface, because of more chemisorption sites for Cu nanoparticles generated on PVC surface. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A structure-property relationship in all-organic dye solar cells is revealed by first-principles molecular dynamics and real-time time-dependent density functional theory simulations, accompanied with experimental confirmation. An important structural feature at the interface, Ti-N anchoring, for a broad group of all-organic dyes on TiO2 is inferred from energetics, vibrational recognition, and electronic data. This fact is contrary to the usual assumption; however, it optimizes electronic level alignment and photoelectron injection dynamics, greatly contributing to the observed efficiency improvement in all-organic cyanoacrylate dye sensitized solar cells. [ABSTRACT FROM AUTHOR]

New charged cyclometalated iridium(III) complexes [Ir(ppy)2(L)](PF6) [ppy = 2-phenylpyridine; L = bis(pyrazol-1-yl)methane (for 1); L = bis(3,5-dimethylpyrazol-1-yl)methane (for 2)] were synthesized and their electrochemical and photophysical properties studied. These complexes with non-π-electron-conjugated ancillary chelates exhibit significantly blueshifted emission relative to those of commonly used derivatives with NN ancillary ligands such as bipyridine or phenanthroline. Both X-ray and theoretical analysis based on time-dependent density functional theory (TD-DFT) reveal that the binding of Ir to the bis(pyrazol-1-yl)methane ancillary ligand is much weaker than that to the phenylpyridine main ligand; the effect is enhanced in the excited state. As a result, the ancillary ligand does not participate in low-energy excitations and triplet emission, and the electronic transitions are concentrated on the main chromophoric ligands. The blueshift feature is attributed to emission originating from the main cyclometalated ligands, in contrast to emitters with the NN chromophoric ancillary ligand. In addition, complex 2 exhibits a one order of magnitude higher non-radiative decay rate than complex 1, which is attributed to the steric hindrance of the methyl groups that leads to a more loosely bound ancillary ligand. [ABSTRACT FROM AUTHOR]

A new particulate drug delivery system with gelatin matrix containing Ibuprofen as a model drug molecule was developed for an epidermis drug prolonged release. Gelatin films containing Ibuprofen‐loaded poly‐ε‐caprolactone (PCL) microspheres have been developed on evaporation of organic solvent from an oil‐in‐water emulsion followed by cross‐linking. The microspheres were characterized for particle size, encapsulation efficiency, and surface morphology. Water uptake, matrix erosion, and drug release profile of the microsphere‐film system were investigated. The results indicated that drug‐loaded microspheres introduced in this system successfully prolonged drug release time. This kind of microsphere‐film system combined good adhesion, typical for gelatin films, with the sustained release performance of PCL microspheres. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to identify factors associated with rupture in elderly patients with acute appendicitis. Methods: The medical records of 601 consecutive patients >60 years of age with acute appendicitis between 1995 and 2005 were retrospectively reviewed. Historical, clinical and laboratory factors in patients with both intact and ruptured appendices were examined with univariate and multivariate analyses by logistic regressions. Results: Nine factors predicted appendiceal rupture age (odds ratio (OR) 1.05, confidence interval (CI) 1.02–1.07), male sex (OR 1.96, CI 1.35–2.06), preadmission duration of pain (OR 1.23, CI 1.11–1.36), interval of time from admission to surgery (OR 1.02, CI 1.01–1.04), fever >38°C (OR 2.59, CI 1.78–3.77), left shift in leucocyte count >76% (OR 2.34, CI 1.27–4.32), anorexia (OR 2.03, CI 1.38–2.99) and a retrocaecally positioned appendix (OR 1.93, CI 1.15–3.24). Conclusion: The incidence of appendiceal rupture, or complications secondary to appendiceal rupture, in elderly patients may be decreased if surgery is expedited when the temperature is >38°C or there is a left shift in leucocyte count >76%, especially in men with anorexia. [ABSTRACT FROM AUTHOR]

The behaviors of a large number of GGA, meta-GGA, and hybrid-GGA density functionals in describing the spin-state energetics of iron porphyrins and related compounds have been investigated. There is a large variation in performance between the various functionals for the calculations of the high-spin state relative energies. Most GGA and meta-GGA functionals are biased toward lower-spin states and so fail to give the correct ground state for the high-spin systems, for which the meta-GGA functionals show more or less improvement over the GGA ones. The GGA functionals that use the OPTX correction for exchange show remarkably high performance for calculating the high-spin state energetics, but their results for the intermediate-spin states are somewhat questionable. A heavily parameterized GGA functional, HCTH/407, provides results which are in qualitative agreement with the experimental findings for the iron porphyrins [FeP, FeP(Cl), FeP(THF)2], but its relative energies for the high-spin states are probably somewhat too low. The high-spin state relative energies are then even more underestimated by the corresponding meta-GGA functional τ-HCTH. For the hybrid-GGA functionals, the Hartree-Fock (HF)-type (or exact) exchange contribution strongly stabilizes the high-spin states, and so the performance of such functionals is largely dependent upon the amount of the HF exchange admixture in them. The B3LYP, B97, B97-1, and τ-HCTH-hyb functionals are able to provide a satisfactory description of the energetics of all the systems considered. © 2006 Wiley Periodicals, Inc. J Comput Chem 27:1577–1592, 2006 [ABSTRACT FROM AUTHOR]

Introduction: Although hypoxia can exacerbate symptoms of various neurological disorders, accumulating evidence has indicated that intermittent hypoxia (IH) may exert protective effects against brain diseases. In the present study, we aimed to determine whether exposure to IH exerts beneficial effects in a transgenic murine model of Alzheimer's disease (AD). Because comorbid anxiety is prevalent among patients with AD, we explored the effects of IH on anxiety‐like behaviors and associated factors in APP/PS1 mice. Methods: APP/PS1 mice were subjected to IH for two weeks. We assessed cognitive performance and anxiety‐related behavior using standard behavioral assessments. Amyloid beta (Aβ) levels in the hippocampus were assessed using immunofluorescence and enzyme‐linked immunosorbent assays (ELISA). We also assessed cell morphology and brain‐derived neurotrophic factor (BDNF) expression in the hippocampus. Results: Exposure to IH significantly increased cognitive performance and decreased anxiety‐related behaviors in APP/PS1 mice. Immunofluorescence and ELISA results revealed that IH pretreatment significantly lowered Aβ levels in the cortex and hippocampus. Morphological studies validated the neuroprotective effect of IH exposure on hippocampal neurogenesis. Molecular studies revealed IH‐enhanced BDNF expression and inhibition of apoptosis‐related protein expression in the hippocampus of APP/PS1 mice. Conclusions: Our study demonstrates that IH improves cognition and reduces anxiety in a murine model of AD. Thus, further studies are required to determine whether IH can be used as a preventive/adjuvant therapy in patients with AD. [ABSTRACT FROM AUTHOR]