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61.
This study proposes a roll‐to‐roll process‐based sub‐wavelength grating, which is attached on a light bar to turn the side‐lit red/green/blue (620, 520, and 450 nm) incident rays into a uniformly and normally output white light with high illuminance from the light bar's surface. On the basis of the rigorous coupling wave analysis, the relationship between the first‐order transmission/reflection efficiency and the pitch of the gratings with different shapes was analyzed. The optimal design can effectively reduce the coupling length and enhance the white color balance for display applications.  相似文献   
62.
We present a filter-and-refine method to speed up nearest neighbor searches with the Kullback–Leibler divergence for multivariate Gaussians. This combination of features and similarity estimation is of special interest in the field of automatic music recommendation as it is widely used to compute music similarity. However, the non-vectorial features and a non-metric divergence make using it with large corpora difficult, as standard indexing algorithms can not be used. This paper proposes a method for fast nearest neighbor retrieval in large databases which relies on the above approach. In its core the method rescales the divergence and uses a modified FastMap implementation to speed up nearest-neighbor queries. Overall the method accelerates the search for similar music pieces by a factor of 10–30 and yields high recall values of 95–99% compared to a standard linear search.  相似文献   
63.
Glycine N-methyltransferase (GNMT) regulates S-adenosylmethionine (SAMe), a methyl donor in methylation. Over-expressed SAMe may cause neurogenic capacity reduction and memory impairment. GNMT knockout mice (GNMT-KO) was applied as an experimental model to evaluate its effect on neurons. In this study, proteins from brain tissues were studied using proteomic approaches, Haemotoxylin and Eosin staining, immunohistochemistry, Western blotting, and ingenuity pathway analysis. The expression of Receptor-interacting protein 1(RIPK1) and Caspase 3 were up-regulated and activity-dependent neuroprotective protein (ADNP) was down-regulated in GNMT-KO mice regardless of the age. Besides, proteins related to neuropathology, such as excitatory amino acid transporter 2, calcium/calmodulin-dependent protein kinase type II subunit alpha, and Cu-Zn superoxide dismutase were found only in the group of aged wild-type mice; 4-aminobutyrate amino transferase, limbic system-associated membrane protein, sodium- and chloride-dependent GABA transporter 3 and ProSAAS were found only in the group of young GNMT-KO mice and are related to function of neurons; serum albumin and Rho GDP dissociation inhibitor 1 were found only in the group of aged GNMT-KO mice and are connected to neurodegenerative disorders. With proteomic analyses, a pathway involving Gonadotropin-releasing hormone (GnRH) signal was found to be associated with aging. The GnRH pathway could provide additional information on the mechanism of aging and non-aging related neurodegeneration, and these protein markers may be served in developing future therapeutic treatments to ameliorate aging and prevent diseases.  相似文献   
64.
Coxsackievirus A16 (CA16) is one of the major causative agents of hand, foot, and mouth disease (HFMD). Children aged <5 years are the most affected by CA16 HFMD globally. Although clinical symptoms of CA16 infections are usually mild, severe complications, such as aseptic meningitis or even death, have been recorded. Currently, no vaccine or antiviral therapy for CA16 infection exists. Single-chain variable fragment (scFv) antibodies significantly inhibit viral infection and could be a potential treatment for controlling the infection. In this study, scFv phage display libraries were constructed from splenocytes of a laying hen immunized with CA16-infected lysate. The pComb3X vector containing the scFv genes was introduced into ER2738 Escherichia coli and rescued by helper phages to express scFv molecules. After screening with five cycles of bio-panning, an effective scFv antibody showing favorable binding activity to proteins in CA16-infected lysate on ELISA plates was selected. Importantly, the selected scFv clone showed a neutralizing capability against the CA16 virus and cross-reacted with viral proteins in EV71-infected lysate. Intriguingly, polyclonal IgY antibody not only showed binding specificity against proteins in CA16-infected lysate but also showed significant neutralization activities. Nevertheless, IgY-binding protein did not cross-react with proteins in EV71-infected lysate. These results suggest that the IgY- and scFv-binding protein antibodies provide protection against CA16 viral infection in in vitro assays and may be potential candidates for treating CA16 infection in vulnerable young children.  相似文献   
65.
Resveratrol can affect the physiology or biochemistry of offspring in the maternal–fetal animal model. However, it exhibits low bioavailability in humans and animals. Fifteen-week SD pregnant female rats were orally administered bisphenol A (BPA) and/or resveratrol butyrate ester (RBE), and the male offspring rats (n = 4–8 per group) were evaluated. The results show that RBE treatment (BPA + R30) compared with the BPA group can reduce the damage caused by BPA (p < 0.05). RBE enhanced the expression of selected genes and induced extramedullary hematopoiesis and mononuclear cell infiltration. RBE increased the abundance of S24-7 and Adlercreutzia in the intestines of the male offspring rats, as well as the concentrations of short-chain fatty acids (SCFAs) in the feces. RBE also increased the antioxidant capacity of the liver by inducing Nrf2, promoting the expression of HO-1, SOD, and CAT. It also increased the concentration of intestinal SCFAs, enhancing the barrier formed by intestinal cells, thereby preventing BPA-induced metabolic disruption in the male offspring rats, and reduced liver inflammation. This study identified a potential mechanism underlying the protective effects of RBE against the liver damage caused by BPA exposure during the peri-pregnancy period, and the influence of the gut microbiota on the gut–liver axis in the offspring.  相似文献   
66.
A mathematical model was used to investigate the effects of electrical inhomogeneities introduced by the intracavitary blood mass and the lungs on the apparent location and magnitude of a current dipole source representing local activity in the myocardium. Radial and tangential current source moments were considered, and lung conductivity was taken as a variable parameter. Both the blood mass and the lungs cause a current source to appear closer to the heart center than it actually is. The effect increases as the source moves away from the endocardial surface, and maximum displacement is estimated to be of the order of 1 cm. The net effect of the inhomogeneities is to increase the magnitude of the radial component of a source dipole while diminishing its tangential component. These effects depend on source location.  相似文献   
67.
The pitting behaviour of type 321 stainless steel in sulfide-containing chloride aqueous environments was studied using cyclic potentiodynamic polarization. A well-established correlation between H2S and Na2S2O3 in the study of corrosion was applied, that is, H2S was simulated by Na2S2O3. The major factors affecting the pitting corrosion of type 321 stainless steel are the Cl- concentration, solution pH and temperature. The results clearly indicate that both Epit and E pp decrease with increasing Cl- concentration and temperature, while I pass is more sensitive to temperature variation. E pit decreased with decreasing pH in the range 2 < pH < 7.5. The surface morphology and chemistry of the corroded type 321 stainless steel resulting from anodic polarization in 0.01 M S2O 3 2- -containing Cl- solution were analysed by XRD, SEM and EPMA. A higher concentration of sulfur was found in the pits, and the dark surface film was mainly composed of FeS and -Fe2O3. The results describe the pitting behaviour of type 321 stainless steel in sulfide-containing Cl- aqueous environments.  相似文献   
68.
In an attempt to improve the colloidal processing of Si3N4 ceramics, we studied the rheology and consolidation of colloidal suspensions of Si3N4 particles (average particle size 0.7 μm) with small Al2O3 particles (average particle size 20 nm). It was found that at pH >7, the viscosity of the mixtures increased and then decreased with an increasing concentration of Al2O3. λpotential measurements, optical micrographs, and visible light absorptance measurement suggest that such viscosity behavior is due to clustering of Si3N4 particles bridged by the small Al2O3 particles. This is also supported by the Derjaquin-Landau-Verwey-Overbeek (DLVO) potential calculations that show the barrier height in the DLVO potential between Al2O3 and Si3N4 is small. The small barrier height under current experimental conditions stems from the small size of the Al2O3 particles. The small barrier height allows the thermal motion of the two kinds of particles to overcome the barrier and attach to each other. The adsorption of small Al2O3 particles on Si3N4 can occur even when both Al2O3 and Si3N4 carry the same sign of charges. The adsorption of Al2O3 on Si3N4 also increases the density of consolidated compacts.  相似文献   
69.
Microstructural characterization of a high-Al2O3 substrate containing cofired thick-film tungsten metallization, with particular emphasis on the metal/ceramic interface, was conducted. The substrate contained tabular Al2O3 grains surrounded by a continuous calcium magnesium aluminum silicate glass containing particles of monoclinic ZrO2 and reduced rutile (TiO2- x ). The metal/ceramic adhesion was caused by mechanical interlocking between the W and Al2O3 grains by the glass phase which penetrated the porous W layers during sintering; there was no interfacial reaction or diffusion zone. The mechanical properties of the W metallization did not limit interfacial strength. Heat treatments of the substrate at 1400 K in air and under vacuum resulted in the devitrification of the intergranular glass. The most abundant devitrification product was anorthite (CaAl2Si2O8), accompanied by magnesium aluminate titanate, magnesium aluminate spinel, α-cristobalite (SiO2), and α-cordierite (Mg2Al4Si5O18). In addition, small rutile particles precipitated within the Al2O3 grains.  相似文献   
70.
Our volume–entropy–energy (VSE) equation of state for liquids, first proposed in 1973 for use with low molecular weight homogeneous liquids, is here applied for the first time to a high molecular weight liquid that is heterogeneous in molecular weight, namely, a molten polymer. Four thermo-dynamic quantities, T, s, cp, and ε are calculated over the range of 600–725 K at ambient pressure and are compared with experimental values, with excellent results. The grand average of the standard percentage errors (S.P.E.) for the 24 points is 0.1100%.  相似文献   
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