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The direct conversion of CO2 to aromatics is an effective strategy for simultaneously achieving carbon neutrality and its resource utilization. However, it is a great challenge to efficient CO2 conversion to high value-added aromatics due to the chemical inertness and characteristics of multi-path conversion of CO2. In this work, a series of nanosized ZSM-5 zeolites [NZ5(x)] with different acid amount and strength were synthesized by a seed-induced template-free method via changing the initial gel composition. The Cr2O3 nanoparticle was prepared by simple precipitation method. The performance of the Cr2O3/NZ5(x) bifunctional catalysts composed of Cr2O3 and nano-ZSM-5 zeolites with different acidity, and mixed Cr2O3 with NZ5 (50) by different ways in the CO2 hydrogenation reaction was investigated. The Cr2O3/NZ5(50) catalyst with suitable acidity and closest metal-acid site distance exhibit the highest aromatics selectivity of 87.2% among all hydrocarbon products at CO2 single-pass conversion of 13.6%, which is due to the synergistic effect between the acid sites of the nanosized ZSM-5 zeolite and metal sites provide by Cr2O3 with abundant oxygen vacancies. [ABSTRACT FROM AUTHOR]

Nanoscale ZSM-5 (AlZ5-D) and Ga-substituted ZSM-5 zeolites ((Al,Ga)Z5-D and GaZ5-D) were synthesized by a green dry-gel conversion strategy. For comparison, ZSM-5 zeolite (AlZ5-T) was also prepared by traditional hydrothermal method. The effects of synthesis method and Ga introduction on the physicochemical property and catalytic behavior of methanol to gasoline (MTG) were studied in detail. The results show that the aromatics selectivity decreased while C 5 + alkanes selectivity increased for AlZ5-D sample compared with that of AlZ5-T, which was attributed to the significantly reduced density of Brønsted acid sites and weakened strong acidity. After Ga introduction, the acid strength of samples further weakened due to the formation of Si—OH—Ga bridge hydroxyl group by insertion of Ga into the zeolite framework, inhibiting the cracking reaction and thus increasing the gasoline selectivity. Moreover, the extra-framework Ga species, especially in the form of GaO+ in GaZ5-D sample, exhibited high dehydrogenation activity, leading to the highest selectivity of aromatics and gasoline. [ABSTRACT FROM AUTHOR]

The emission mechanism in organic light-emitting devices, where the emission layer is composed of Eu(DBM)3pyzphen (DBM=Dibenzoylmethane, pyzphen=pyrazino-[2,3-f][1,10]-phenanthroline) doped into electron transporting/hole blocking material BPhen (4,7-diphenyl-1, 10-phenanthroline), is investigated. Energy transfer and carrier trapping simultaneously exist in the luminescence process, and carrier trapping is a main process. Direct carrier trapping by Eu(DBM)3pyzphen molecules is confirmed by the difference of electroluminescence and photoluminescence spectra as well as J-V characteristics. Efficient Föster and Dexter energy transfer from BPhen to Eu(DBM)3pyzphen molecules were speculated in terms of analysis of photoluminescence spectra of fixed solutions, triplet energies, and phosphorescent lifetimes. Based on these mechanisms, the overall performances of these devices were improved. High efficiencies were obtained under carrier trapping by Eu(DBM)3pyzphen molecules, and the emission of BPhen was eliminated by efficient energy transfer from the BPhen to Eu(DBM)3pyzphen molecules. [ABSTRACT FROM AUTHOR]

An exciplex can be formed due to the charge transfer between the lowest unoccupied molecular orbital (LUMO) of the acceptor and the highest occupied molecular orbital (HOMO) of the donor. By introducing a mixing layer composed of [N,N′-diphenyl-N,N′bis (3-methylphenyl)-1,1′-diphenyl-4,4′-diamine] (TPD) and europium(dibenzoylmethanato)3(bathophenanthroline) [Eu(DBM)3bath] and a graded interface, elimination of light emission from the exciplex and significant luminescence enhancement of trivalent europium ions (Eu3+) in organic light emitting devices have been achieved. The elimination mechanism of exciplex emission based on the concept that an exciplex can be formed between LUMO of the acceptor (Eu complex) and HOMO of donor (TPD) was investigated. To comprehensively understand the mechanism, devices consisting of a Eu(DBM)3bath as the emitting material and the devices using other rare-earth (RE) complex [RE(DBM)3bath] as the emitting material were fabricated with the same device configuration. As a reference, four spin-coated films with the blend composed of TPD and the gadolinium complex [Gd(DBM)3bath] were also fabricated. The electroluminescence (EL) spectra from the devices and photoluminescence spectra from the spin-coating films were fully investigated. The results show that the exciplex was formed by the charge transfer from the donor TPD to the acceptor RE complex, the exciplex state that acted as a transient excited state can be controlled by altering the molecular ratio in the mixing films. The relation of the exciplex formation based on EL devices with the RE complex versus the variety of the RE ions is also discussed by manipulating the energy level of the excited state. [ABSTRACT FROM AUTHOR]

The maturation of dendritic cells is critical for chronic rhinosinusitis with nasal polyps (CRSwNPs), especially eosinophilic chronic rhinosinusitis with nasal polyps (EosCRSwNPs), but the regulation mechanism of dendritic cells (DCs) maturation is still unclear. We identified nasal mucosa of 20 patients with EosCRSwNP, 16 non-EosCRSwNP patients, and inferior turbinate of 14 patients with nasal septum deviation after surgery. The expression of cyclin-dependent kinase 5 (CDK5) and programmed cell death 1 ligand 1 (PD-L1) were detected by immunofluorescent, real-time quantitative PCR, and Western blot in EosCRSwNP. The level of dendritic cell maturation was detected by flow cytometry and immunofluorescence staining after CDK5 expression interference with small interfering RNA (siRNA). The expression of CDK5 and PD-L1 in EosCRSwNP nasal mucosal tissue was significantly higher than that of non-EosCRSwNP and inferior turbinate nasal mucosa tissue, and there was a positive correlation between them. Immunofluorescence staining showed that CDK5 and PD-L1 were co-localized in dendritic cells. Synergistic stimulation of dendritic cells with LPS and TNF-α promotes the maturation of dendritic cells and increases the expression of CDK5 and PD-L1. However, blocking the expression of CDK5 in dendritic cells with siRNAs leads to a blockage of cell maturation. CDK5 can regulate the expression of PD-L1, and its presence is critical for the maturation of dendritic cells. CDK5 may play an important role in the pathogenesis of CRSwNP disease. [ABSTRACT FROM AUTHOR]

Vibrational population up to v″=3 in the umbrella mode of CD3 thermally desorbed from GaAs(100) has been determined by resonance enhanced multiphoton ionization (REMPI) spectroscopy. The population ratios are superthermal. The methyl radical must desorb promptly with a transition state geometry significantly different from the planar gas phase geometry. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Understanding photochemistry and energy transfer mechanisms in molecular solid films is of interest to many scientific issues, ranging from matrix-assisted laser desorption ionization mass spectrometry to photochemical processes on polar stratospheric cloud particles. We present a study of a model system: the photochemistry (hν=1.2–6.4 eV) of a molecular Cl2CO solid film at low laser power density, 10 μJ–1 mJ/cm2 for ∼10 ns pulses. At hν≥3.5 eV, photon absorption by Cl2CO leads to a major photodissociation channel resulting in CO (g) and Cl (g) and a minor molecular Cl2CO ejection channel. Both photodissociation and molecular ejection are observed at the lowest laser power density and their yields depend linearly on pulse energy. This result establishes a single photon photoexcitation mechanism. The electronically excited Cl2CO in the surface region of the solid film can either dissociate or convert its electronic energy to translational motion in Cl2CO. The translational energy distribution of CO (g) from the photodissociation channel is bimodal: the flux-weighted mean translational energy of the fast channel is photon energy dependent (=210, 135, and ∼90 meV at hν=6.4, 5.0, and 3.5 eV, respectively), while the slow channel is independent of photon energy and corresponds to completely thermalized CO molecules (=84±3 K). The mean translational energy of photoejected Cl2CO is =220±20 meV. In addition to photoejection, there is also a distinctively different thermal desorption channel due to transient laser heating. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The translational, rotational, and vibrational state distributions of CO (g) resulting from the single photon photodissociation of Cl2CO in the condensed phase at ∼90 K have been determined by time-of-flight (TOF) distribution measurement and resonance-enhanced multiphoton ionization (REMPI) spectroscopy. The TOF distribution of CO (g) is bimodal. Internal state characterization of the slow channel reveals a completely thermalized origin, with a rotational temperature of Trot=88±5 K, which is equal to the translational temperature as well as the substrate temperature. We believe these slow CO molecules originate from photodissociation below the topmost surface of the molecular film and achieve thermal equilibrium with the substrate before escaping into the gas phase. Internal state characterization of the fast channel shows, on the other hand, an energetic origin: at hν=5.0 eV, the rotational distribution, with an overall flux-weighted mean rotational energy of =0.12±0.01 eV, is non-Boltzmann and can be approximated by a bimodal distribution with rotational temperatures of 210±40 K at low J″(s) and 2200±300 K at high J″(s); the relative vibrational population is Nν=1/Nν=0=0.33±0.05. Both rotational and translational distributions of fast CO show positive correlation with photon energy. These CO molecules must be promptly ejected into the gas phase, carrying nascent energetic information from the photodissociation reaction on the surface of the molecular film. For electronic excitation events that result in photodissociation, 74% of the excess excitation energy is distributed in the translational and internal motions of products (CO and Cl); only 26% of the available energy is converted to motions of surrounding molecules. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

State resolved characterization of nascent gas phase products is used as probe for the dynamics of an energetic surface reaction. This is achieved in the photodissociation of monolayer phosgene adsorbed on Ag(110). Irradiation of adsorbed Cl2CO in a broad photon energy range (hν=1.9–6.4 eV) leads to dissociation, with Cl retained on the surface and CO desorbing into the gas phase. The translational energy of product CO (g), =0.26 eV, is independent of hν, even at the threshold photon energy (1.9 eV). This result establishes a dissociative electron attachment mechanism involving a reactive intermediate, ClCO, whose prompt dissociation serves as a probe to surface dissociation dynamics. Consistent with translation, internal state distribution of product CO (g) also shows an energetic origin: The rotational distribution, with an overall flux-weighted mean rotational energy of =0.17 eV, can be approximated by a bimodal Boltzmann distribution with rotational temperatures of 700 K at low J(s) and 7000 K at high J(s); the relative vibrational population is Nν=1/Nν=0=0.30. Contrary to common expectation based on quenching rates, both translational and rotational energies of CO (g) from monolayer photodissociation are much higher than those from the direct photodissociation in multilayers. This is taken as evidence for concerted reaction dynamics on the surface: The high exothermicity in the Cl–Ag bond formation on the surface exerts part of the energy to the Cl–CO coordinate, leading to higher energies in CO (g). © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Some evidence has shown that O(6)-methylguanine DNA methyltransferase (MGMT) plays a key role in the pathogenesis of Esophageal Adenocarcinoma (EA) in some populations but not Chinese Han. The objective of this study is to investigate this issue. Three SNPs (rs11016879, rs7069143, rs7071825) were genotyped in 205 unrelated EA patients and 216 healthy controls matched for age and gender using pre-designed TaqMan SNP genotyping assay kits on an ABI PRISM 7900 HT Sequence Detection System. Meanwhile, expression level of MGMT was measured by quantitative real-time reverse-transcription polymerase chain reaction (RT-PCR), including 102 patients for EA and 113 healthy controls. The alleles distribution of rs11016879 (G/A, OR = 1.412, 95% CI = 1.053-1.894, P = 0.021) and the genotypes distribution of rs7069143 (CC/CT, OR = 1.580, 95% CI = 1.047-2.384, P = 0.029) significantly differed between the case and control groups. The expression level of MGMT significantly reduced in patients (control, 0.963 ± 0.094; case, 0.586 ± 0.083; P = 0.022), which was correlated with an increased risk for EA. These findings indicated that the association between MGMT and EA might exist in Chinese Han. [ABSTRACT FROM AUTHOR]

FMR1 premutation carriers (55-199 CGG repeats), and potentially women with high normal (35-44) or low normal (<28) CGG repeats, are at risk of premature ovarian aging. The scarcity of population data on CGG repeats <45 CGG, and variation in race–ethnicity, makes it difficult to determine true associations. DNA was analyzed for FMR1 CGG repeat lengths from 803 women (386 caucasians, 219 African Americans, 102 Japanese, and 96 Chinese) from the US-based Study of Women’s Health Across the Nation (SWAN). Participants had ≥1 menses in the 3 months before enrollment, ≥1 pregnancy, no history of infertility or hormonal therapy, and menopause ≥46 years. Statistical analyses used Fisher exact tests. Among these women with normal reproductive histories, significant FMR1 repeat length differences were found across race-ethnicity for both the longer (P = .0002) and the shorter (P < .0001) alleles. The trinucleotide length variance was greater for non-Asian than Asian women (P < .0001), despite identical median values. Our data indicate that short allele lengths <25 CGG on one or both alleles are more common in non-Asian than Asian women. We confirm the minor allele in the 35 to 39 CGG range among Asians as reported previously. Only 2 (0.3%) premutation carriers were identified. These data demonstrate that FMR1 distributions do vary by race–ethnicity, even within the “normal” range. This study indicates the need to control for race–ethnicity in FMR1 ovarian aging research and provides race–ethnic population data for females separated by allele. [ABSTRACT FROM AUTHOR]

Modeling vegetation photosynthesis is essential for understanding carbon exchanges between terrestrial ecosystems and the atmosphere. The radiative transfer process within plant canopies is one of the key drivers that regulate canopy photosynthesis. Most vegetation cover consists of discrete plant crowns, of which the physical observation departs from the underlying assumption of a homogenous and uniform medium in classic radiative transfer theory. Here we advance the Geometric Optical Radiative Transfer (GORT) model to simulate photosynthesis activities for discontinuous plant canopies. We separate radiation absorption into two components that are absorbed by sunlit and shaded leaves, and derive analytical solutions by integrating over the canopy layer. To model leaf-level and canopy-level photosynthesis, leaf light absorption is then linked to the biochemical process of gas diffusion through leaf stomata. The canopy gap probability derived from GORT differs from classic radiative transfer theory, especially when the leaf area index is high, due to leaf clumping effects. Tree characteristics such as tree density, crown shape, and canopy length affect leaf clumping and regulate radiation interception. Modeled gross primary production (GPP) for two deciduous forest stands could explain more than 80 % of the variance of flux tower measurements at both near hourly and daily timescales. We demonstrate that ambient CO2 concentrations influence daytime vegetation photosynthesis, which needs to be considered in biogeochemical models. The proposed model is complementary to classic radiative transfer theory and shows promise in modeling the radiative transfer process and photosynthetic activities over discontinuous forest canopies. [ABSTRACT FROM AUTHOR]

Modeling vegetation photosynthesis is essential for understanding carbon exchanges between terrestrial ecosystems and the atmosphere. The radiative transfer process within plant canopies is one of the key drivers that regulate canopy photosynthesis. Most vegetation cover consists of discrete plant crowns, of which the physical observation departs from the underlying assumption of a homogenous and uniform medium in classic radiative transfer theory. Here we advance the Geometric Optical Radiative Transfer (GORT) model to simulate photosynthesis activities for discontinuous plant canopies. We separate radiation absorption into two components that are absorbed by sunlit and shaded leaves, and derive analytical solutions by integrating over the canopy layer. To model leaf-level and canopy-level photosynthesis, leaf light absorption is then linked to the biochemical process of gas diffusion through leaf stomata. The canopy gap probability derived from GORT differs from classic radiative transfer theory, especially when the leaf area index is high, due to leaf clumping effects. Tree characteristics such as tree density, crown shape, and canopy length affect leaf clumping and regulate radiation interception. Modeled gross primary production (GPP) for two deciduous forest stands could explain more than 80% of the variance of flux tower measurements at both near hourly and daily time scales. We also demonstrate that the ambient CO2 concentration influences daytime vegetation photosynthesis, which needs to be considered in state-of-the-art biogeochemical models. The proposed model is complementary to classic radiative transfer theory and shows promise in modeling the radiative transfer process and photosynthetic activities over discontinuous forest canopies. [ABSTRACT FROM AUTHOR]

Land surface phenological cycles of vegetation greening and browning are influenced by variability in climatic forcing. Quantitative spatial information on phenological cycles and their variability is important for agricultural applications, wildfire fuel accumulation, land management, land surface modeling, and climate change studies. Most phenology studies have focused on temperature-driven Northern Hemisphere systems, where phenology shows annually recurring patterns. However, precipitation-driven nonannual phenology of arid and semi-arid systems (i.e., drylands) received much less attention, despite the fact that they cover more than 30% of the global land surface. Here, we focused on Australia, a continent with one of the most variable rainfall climates in the world and vast areas of dryland systems, where a detailed phenological investigation and a characterization of the relationship between phenology and climate variability are missing. To fill this knowledge gap, we developed an algorithm to characterize phenological cycles, and analyzed geographic and climate-driven variability in phenology from 2000 to 2013, which included extreme drought and wet years. We linked derived phenological metrics to rainfall and the Southern Oscillation Index (SOI). We conducted a continent-wide investigation and a more detailed investigation over the Murray-Darling Basin (MDB), the primary agricultural area and largest river catchment of Australia. Results showed high inter- and intra-annual variability in phenological cycles across Australia. The peak of phenological cycles occurred not only during the austral summer, but also at any time of the year, and their timing varied by more than a month in the interior of the continent. The magnitude of the phenological cycle peak and the integrated greenness were most significantly correlated with monthly SOI within the preceding 12 months. Correlation patterns occurred primarily over northeastern Australia and within the MDB, predominantly over natural land cover and particularly in floodplain and wetland areas. Integrated greenness of the phenological cycles (surrogate of vegetation productivity) showed positive anomalies of more than 2 standard deviations over most of eastern Australia in 2009-2010, which coincided with the transition from the El Niño-induced decadal droughts to flooding caused by La Niña. [ABSTRACT FROM AUTHOR]

Interferon (IFN) activation signaling and T helper 17 (Th17)-cell/B-cell regulation play a critical role in the pathogenesis of systemic lupus erythematosus ( SLE). Several studies have provided convincing evidence that polymorphisms in IRF5, STAT4, IKZF1 and ETS1 from these pathways may be involved in SLE by affecting gene expression or epistasis. We analyzed the genetic interaction in known SLE susceptibility loci from the four genes in northern Han Chinese. A total of 946 northern Han Chinese participated in this study (370 unrelated SLE patients and 576 healthy controls). Subjects underwent genotyping for the single-nucleotide polymorphisms ( SNPs) rs2004640 in IRF5, rs7574865 in STAT4, rs4917014 in IKZF1 and rs1128334 in ETS1 by use of a TaqMan SNP genotyping assay and direct sequencing. Gene-gene interaction analysis involved direct counting, multifactor dimensionality reduction ( MDR) and linear regression analysis. SLE patients and controls differed in allele frequencies of rs7574865, rs1128334 ( P < 0.001) and rs4917014 ( P < 0.01). Direct counting revealed that the frequency of risk homozygote combinations was higher for SLE patients than controls ( P < 0.01). Furthermore, 2-, 3- and 4-way gene-gene epistasis in SLE was confirmed by parametric methods and MDR analysis. Gene expression analysis partially supported the findings. Our study confirmed the association of the IFN pathway or Th17/B-cells and the pathogenesis of SLE, and gene-gene interaction in this pathway may increase the risk of SLE. [ABSTRACT FROM AUTHOR]

Introduction: Hereditary spastic paraplegia (HSP) belongs to a large, heterogeneous group of progressive neurodegenerative diseases characterised by progressive lower extremity weakness and spasticity, which is caused by developmental failure or degeneration of motor axons in the corticospinal tract. Classical genetic studies have identified at least 46 genetic loci responsible for HSP.Methods: A genetic study was conducted on a four-generation Chinese family with autosomal dominant HSP. The SPAST gene was investigated using linkage analysis and direct sequencing. Findings were compared with unaffected family members and 50 normal, unaffected individuals who were matched for geographical ancestry.Results: We identified a novel 14-bp heterozygous deletion that induced a frameshift mutation in exon 15 of SPAST (SPG4). This mutation is predicted to have functional impact and found to cosegregate with the disease phenotype.Conclusion: Our results have expanded the mutation spectrum of the SPAST gene. These findings could help clinicians provide prenatal diagnosis of affected foetuses in families with a known history of such neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

The incipient fault discharge detection in power transformers is one of the crucial methodologies to prevent serious system damage incurred from deterioration of electrical insulation. In this paper, we propose a new scheme to detect incipient fault discharge for power transformers, which is based on a novel ultraviolet assay approach. In this method, we derive a new detection model by a careful analysis for ultraviolet light characteristics and properties due to fault discharge from the corresponding power transformers. Combining with a new positioning scheme, we show that our corona discharge detection approach can efficiently compute and determine the locations of fault transformers with high accuracy that also outperforms the existing detection methods in the literature. [ABSTRACT FROM AUTHOR]

In order to solve the defects that the end-effect of magnetic field is ignored in two dimension (2-D) analytical method or 2-D finite element method (FEM); meanwhile, mass computer resource and time for parametric design or optimization are wasted in three dimension (3-D) FEM, a concise and efficient 3-D analytical approach is put forward for the calculation of the air-gap magnetic field and torque of coaxial magnetic gears. Based on the cylindrical coordinates where a coaxial magnetic gear is in, the equivalent current model and vector magnetic potential equation of permanent magnets in high speed permanent magnetic ring are constituted. By superposed magnetic flux density of every tile permanent magnets on high speed permanent magnetic ring in cylindrical coordinates, a air-gap magnetic field 3-D analytical formula is set up without ferromagnetic pole-pieces; in the interest of modulated air-gap magnetic field 3-D analytical formula with ferromagnetic pole-pieces, three types boundary conditions using state equations of contact surfaces between ferromagnetic pole-pieces and air-gap are established by a thorough analysis of the modulate mechanism of ferromagnetic pole-pieces. Finally, magnets of the low speed permanent magnetic ring are reduced to a distribution of equivalent current, which experience the Lorentz force in modulated magnetic field of high speed permanent magnetic ring for torque calculation. The integrals in all aforementioned calculation are axial, so the end-effect is embodied in above analytical model and more precise than 2-D analytical method or 2-D FEM. As the calculation results, the formula is accurate but faster than the 3-D FEM. The analytical model is suited for programmable calculation and that will make the structural and parametric design or optimization of coaxial magnetic gears simple and timesaving. [ABSTRACT FROM AUTHOR]

Two recent genome-wide association studies of East Asian populations revealed three genetic variants in WDFY4/LRRC18 associated with systemic lupus erythematosus (SLE). To identify the gene contributing to this disease susceptibility, we examined the mRNA expression of WDFY4 and LRRC18 in patients with SLE and healthy controls. WDFY4 was significantly downregulated in SLE patients as compared with controls. We used allelic expression and dual-luciferase assays to identify the functional variant. Transcriptional activity was lower for the rs877819A than -G allele. Electrophoretic mobility shift and supershift assays revealed that the transcription factor Yinyang1 (YY1) binds to rs877819, with lower affinity to the A allele, which explained the reduced transcriptional activity. This effect was further confirmed by YY1 small interfering RNA knockdown, overexpression and chromatin immunoprecipitation experiments. rs877819 in WDFY4 might be the functional site associated with SLE by reduced binding of YY1 and downregulating WDFY4 expression. [ABSTRACT FROM AUTHOR]

Vascular disease, such as atherosclerosis, is accompanied by changes in the mechanical properties of the vessel wall. Although altered mechanics is thought to contribute to disease progression, the molecular mechanisms whereby vessel wall stiffening could promote vascular occlusive disease remain unclear. It is well known that platelet-derived growth factor (PDGF) is a major stimulus for the abnormal migration and proliferation of vascular smooth muscle cells (VSMCs) and contributes critically to vascular disease. Here we used engineered substrates with tunable mechanical properties to explore the effect of tissue stiffness on PDGF signaling in VSMCs as a potential mechanism whereby vessel wall stiffening could promote vascular disease. We found that substrate stiffness significantly enhanced PDGFR activity and VSMC proliferation. After ligand binding, PDGFR followed distinct routes of activation in cells cultured on stiff versus soft substrates, as demonstrated by differences in its intensity and duration of activation, sensitivity to cholesterol extracting agent, and plasma membrane localization. Our results suggest that stiffening of the vessel wall could actively promote pathogenesis of vascular disease by enhancing PDGFR signaling to drive VSMC growth and survival. J. Cell. Physiol. 225: 115–122, 2010. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Supported nano-amorphous alloy NiB/MCM-41 catalysts were prepared by chemical reductive deposition. The as-prepared catalysts were characterized by XRD, SEM, TEM, EDAX, ICP, and N2 adsorption-desorption. The amorphous alloy structure of NiB active sites, mesoporous structure of catalysts, and higher BET area have been proved by the experiments. The catalysts have given excellent catalytic activity and selectivity in the production of 3-(N-benzyl)-amino-4-methoxy- acetanilide from 3-amino-4-methoxy-acetanilide and benzaldehyde. [ABSTRACT FROM AUTHOR]

Two Pt/C catalysts with different particle sizes (Pt/C: 2.5 nm, Pt/C-700Ar: 5.1 nm) were investigated by applying a half-cell configuration — rotating disk electrode (RDE) technique in H2SO4 aqueous solutions in the absence of or in the presence of methanol with different concentrations. Pt/C catalyst exhibited higher mass activity in H2SO4 aqueous solution without methanol and slightly lower mass activity in H2SO4 plus 0.1 mol/L CH3OH in comparison with that of Pt/C-700Ar catalyst. On the contrary, single direct methanol fuel cell (DMFC) tests showed that Pt/C exhibited higher oxygen reduction reaction (ORR) activity and better cell performance, mainly due to the different kinds of electrolyte properties. Furthermore, it suggested that a better single DMFC performance could be obtained with a smaller particle size Pt-based cathode catalyst. [ABSTRACT FROM AUTHOR]

In the present investigation, the methanol crossover rate through Nafion®-115 membrane at different temperatures and different concentrations had been investigated in a fuel cell test apparatus by using gas chromatography analysis. The single direct methanol fuel cell (DMFC) tests were carried out to investigate the effect of the concentration of methanol aqueous solutions and cell temperature on methanol crossover and consequently, on the open circuit voltage and the cell performance of DMFC. It can be found that the methanol crossover rate through Nafion® membrane increases as methanol concentration and temperature increase. It can also be found that methanol crossover presented a negative effect on the open circuit voltage and the single DMFC performance. Single DMFC test results showed that an improved cell performance was obtained as temperature increased although the methanol crossover rate increased with temperature increment. [ABSTRACT FROM AUTHOR]

A set of Mo2N-based bimetallic catalysts with high surface area around 140 m 2 /g have been successfully prepared from precursors obtained using the coprecipitation method. Both the precursors and the end-catalysts were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The nitriding processes were monitored by differential thermal analysis (TDA). The catalytic properties of Co-Mo bimetallic catalyst under mediumpressure (3.0 MPa) are much better for the hydrodenitrogenation of pyridine than those of pure γ-Mo2N and a commercially used sulfided CoMo/Al2O3 catalyst. The introduction of the second metal component has been shown to disrupt the morphology of the nitride phase with a greater concentration of (111) planes being present compared to (200) planes, a situation that is reversed compared to γ-Mo2N. [ABSTRACT FROM AUTHOR]

A compact Yagi-Uda antenna for vehicle directional communications in tactical VHF (30-88 MHz) is presented. A special double-folded monopole is designed as the element of the Yagi-Uda antenna to realise compact size and high directivity. The proposed antenna designed and optimised at 59 MHz can utilise the vehicle space reasonably with greatly compact height (0.1199λ) and space between elements (0.125λ). It has satisfactory performances of high directivity, gain (6.3 dBi) and front-to-back ratio (8.6 dB) in the operating band (VSWR<2), better than the typical monopole-type Yagi-Uda antenna. Thus, it is suitable for vehicle directional communications in tactical VHF. The effectiveness of the design is verified by a scaled-down model at 1 GHz. [ABSTRACT FROM AUTHOR]

The relationship between the electroluminescent (EL) efficiencies of interfacial exciplex emission and the lowest unoccupied molecular orbital (LUMO) of the acceptors systematically investigated. A nearly linear relationship was observed between LUMOs of acceptors and exciplex efficiency for a fixed donor of 4,4′,4″-tris[3-methyl-phenyl(phenyl)amino]-triphenylamine in exciplex-type devices. This result indicates that the lower the LUMO of the acceptor is, the higher the EL efficiency of the exciplex is. The effect of acceptor on the efficiencies of exciplex-type devices is attributable to the interactions between the donor and acceptor molecules, which were closely related to the matched LUMOs and intermolecular conformations overlap between donor and acceptor molecules. [ABSTRACT FROM AUTHOR]

High-efficiency, pure red organic light-emitting devices were fabricated by doping a europium-complex Eu(DBM)3pyzphen (DBM=dibenzoylmethane, pyzphen=pyrazino[2,3-f][1,10]phenanthroline) into 4,7-diphenyl-1,10-phenanthroline as emission layer. A maximum current efficiency of 5.1 cd/A at the current density of 1.2 mA/cm2 and a maximum luminance of 1400 cd/m2 were obtained from a 25 wt % Eu(DBM)3pyzphen doped device. High efficiencies were maintained at high current densities and high luminance. For example, at the current density of 10 mA/cm2, the efficiency reached 3.8 cd/A. It means that the efficiency roll-off, a major obstacle to the development of Eu-complex ogranic light-emitting devices, was greatly alleviated. The mechanisms behind the improvement are discussed. [ABSTRACT FROM AUTHOR]

A GaS thin film has been formed epitaxially on GaAs(100) using a photoassisted growth-etching reaction between H2S and the GaAs substrate. In the reaction, the growth of GaS is accomplished via the replacement of As in the GaAs lattice by the photochemically generated S atom, while As is etched from the substrate as arsenic sulfide. The surface of the resulting GaS thin film is characterized by a sharp (2×1) low energy electron diffraction pattern, indicating excellent crystalline quality. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The article CDK5 Regulates PD-L1 Expression and Cell Maturation in Dendritic Cells of CRSwNP, written by C. C. Liu, H. L. Zhang, L. L. Zhi, P. Jin, L. Zhao, T. Li, X. M. Zhou, D. S. Sun, G. H. Cheng, Q. Xin, L. Shi, and M. Xia was originally published electronically on the publisher's internet. [ABSTRACT FROM AUTHOR]