22 research outputs found
Inverse problems for Sturm-Liouville equations with boundary conditions linearly dependent on the spectral parameter from partial information
[[abstract]]Abstract.In this paper, we study the inverse spectral problems for Sturm–Liouville equations with boundary conditions linearly dependent on the spectral parameter and show that the potential of such problem can be uniquely determined from partial information on the potential and parts of two spectra, or alternatively, from partial information on the potential and a subset of pairs of eigenvalues and the normalization constants of the corresponding eigenvalues.[[notice]]補正完畢[[journaltype]]國外[[incitationindex]]SCI[[ispeerreviewed]]Y[[booktype]]紙本[[booktype]]電子版[[countrycodes]]DE
Enhanced light output power in InGaN light-emitting diodes by fabricating inclined undercut structure
The InGaN-based light-emitting diode (LED) with an inclined undercut structure is fabricated through the photoelectrochemical two-step process to increase light extraction efficiency. In the first step the sidewall-undercut structure at the p-type and n-type GaN interface is created by selective wet oxidation on an n-type GaN surface in pure H2O solution. In the second step an inclined undercut structure through a crystallographic wet-etching process is formed by immersion in hot KOH solution. This crystallographic wet-etching process can remove the Ga2O3 layer and form a {1011} p-type GaN stable plane, {1010} n-type GaN stable plane on the mesa sidewall. This inclined p-type GaN plane of LED structure can provide the higher overlap of incident light beam core and extraction core overlap on the mesa sidewall, and the total light output power of the treated LED is 2.10 times higher than the standard LED. Consequently, this inclined undercut LED structure is suitable for high-efficiency nitride-based LED application. (c) 2006 The Electrochemical Society
Protective immunity conferred by recombinant Pasteurella multocida lipoprotein E (PlpE)
The genes encoding Pasteurella multocida lipoprotein E (PlpE) and lipoprotein B (PlpB) were cloned from P. multocida strain X-73 (serotype A:1) and expressed in Escherichia coli. The protective immunity conferred by recombinant PlpE (r-PlpE) and PlpB (r-PlpB) on mice and chickens was evaluated. The results showed that mice immunized with 10 mu g of purified r-PlpE were protected (80-100% survival rate) against challenge infection with 10 or 20 LD50 of P. multocida strains X-73 (serotype A:1), P-1059 (serotype A:3) and P-1662 (serotype A:4). In contrast, mice immunized with r-PlpB were not protected. Chickens immunized with 100 mu g of purified r-PlpE were protected (63-100% survival rate) against lethal challenge infection with strains X-73 and P-1662, whereas those immunized with r-PlpB were not. Sequence analyses showed that PlpE from different strains of P. multocida exhibited 90.8-100% sequence identity to each other, suggesting that PIpE might serve as a cross-protective antigen. This is the first report of a recombinant P. multocida antigen that confers cross protection on animals. (c) 2007 Elsevier Ltd. All rights reserved
Recombinant proteins containing the hypervariable region of the haemagglutinin protect chickens against challenge with Avibacterium paragallinarum
The haemagglutinin (HA) protein plays a key role in the immunogenicity and pathogenicity of Avibacterium paragallinarum, but the domain organization and antigenicity exhibited by different domains of this protein remain unknown. This study reports the presence of a hypervariable region in the HA proteins of strains of serovars A and C of A. paragallinarum. This hypervariable region is located approximately at residues 1100-1600 of the HA protein. The sequence identity found in this hypervariable region was only 18.1%, whereas those upstream and downstream of this region were 83.8 and 97.8%, respectively. Western blot analyses using antisera against the whole-cell antigens of A. paragallinarum showed that the hypervariable region was more antigenic than other regions of the HA protein. Moreover, the antigenicity of the hypervariable region was serovar-specific. Chickens immunized with recombinant proteins that contained the hypervariable region were protected (83-100% protection rate) against challenge infection with A. paragallinarum of the homologous serovar. These results suggest that recombinant proteins containing the hypervariable region may be useful antigens for use in the development of a vaccine against A. paragallinarum. (C) 2010 Elsevier Ltd. All rights reserved
Modeling on chlorophyll a and phycocyanin production by Spirulina platensis under various light-emitting diodes
Light-emitting diodes (LEDs) with various light wavelengths (red, yellow, green, blue and white) and various levels of light intensity (750, 1500 and 3000 mu mol m(-2) s(-1)) are applied to study the effects of light sources on chlorophyll a (Chl) and phycocyanin (Phy) production of Spirulina platensis. Logistic rate equations are used to depict the kinetic behavior of algal growth and pigments formation under various light sources and intensities. According to the regression results, a red LED is the best for algae growth. On the other hand, yellow light gives the best specific Chl production rate with a light intensity of 750 or 1500 mu mol m(-2) s(-1), and blue light yields the best specific pigments (for Chl and Phy) production rates at 3000 mu mol m(-2) s(-1). From the model fitting results, it is found that, at a higher light intensity, a higher specific Chl production rate accompanied by a higher S. platensis biomass is obtained. However, as for Phy production, a higher biomass results in a lower specific Phy production rate. The only exception is the use of blue light, which shows a positive effect on both Chl and Phy production rates under a higher light intensity. (C) 2010 Elsevier B.V. All rights reserved
Chemical-Mechanical Lift-Off Process for InGaN Epitaxial Layers
An InGaN-based light-emitting diode (LED) structure was separated from a GaN/sapphire structure by inserting sacrificial Si-doped InGaN/GaN superlattice layers through a chemical-mechanical lift-off (CMLO) process. The CMLO process consisted of a band-gap-selective photoelectrochemical lateral wet etching process and a mechanical lift-off process. A lower elastic modulus and hardness of the lateral-etched LED structure were measured compared with the conventional LED structure, which indicated a weak mechanical property of the treated LED structure. The photoluminescence blue-shift phenomenon and the Raman redshift phenomenon indicated that the compressive strain from the bottom GaN/sapphire structure was released through the CMLO process. (C) 2011 The Japan Society of Applied Physic