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The article presents a survey of the rare coding variants in candidate genes in schizophrenia by deep sequencing. Topics discussed include 525 patients diagnosed of having schizophrenia, coding sequences through the use Nimblegen capture array and Illumina HiSeq paired-end sequencing at the Beijing Genome Institute (BGI) Inc., and damaging missense variants which can contribute schizophrenia etiology.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010. [ABSTRACT FROM PUBLISHER]

Seed oils of Cuphea are characterized by a diverse assemblage of fatty acid patterns emphasizing short- and medium-chain fatty acids. For this report, seed oils of 19 populations from 14 species were analyzed. Thirteen species are from Brazil and one from Nicaragua. Fatty acid compositions of oils of eight species are reported for the first time. Lauric acid predominates in 10 species, myristic acid in one, and linoleic acid in three. Small amounts of C20:0 and C20:1 are recorded in one species. The major fatty acid for each taxonomic section is consistent with that reported earlier as characteristic of the section. Seed oil compositions of species previously reported from North or Central American populations are comparable to those of the Brazilian populations. [ABSTRACT FROM AUTHOR]

Nineteen species of 10 taxonomic sections of Cuphea were analyzed for fatty acid composition of the seed oils. Two sections of the genus, Trispermum and Pseudocircaea, previously unreported, are included. Lauric acid is the major component of the seed oil in seven of the species surveyed; capric and myristic each predominate in five. Linolenic acid, previously thought to be only a trace component of Cuphea seed oils, is the major constituent of two species. Two others are rich in linoleic acid, another minor component of most Cupbea oils. [ABSTRACT FROM AUTHOR]

Prompted by the previous discovery that (9Z,11E,13E)-9,11,13-octadecatrienoic acid (α-eleostearic acid) was one of the compo-nents responsible for the boll weevil feeding deterrency of tung oil, the seeds of 11 other plant species were extracted with pentane and the oils were evaluated for their feeding deterrency in the laboratory. The oils of Calendula suffruticosa, Centrantbus macro-siphon, Jacaranda mimosifolia and Momordica cochincbinenis were effective feeding deterrents for the boll weevil. [ABSTRACT FROM AUTHOR]

A rapid liquid chromatographic method for the quantitation of trivernolin in epoxy seed oils has been developed. A weighed sample of the oil is dissolved in chloroform (∼100-300 mg/ml), and a 1-20 µl portion of the oil is chromatographed on a 2 ft×1/4 in. OD C µ-Bondapak column with acetonitrile-acetone (2:1, v/v). The area of the trivernolin peak from the differential refractometer recorder tracing is converted to µg trivernolin by use of a calibration curve of peak area vs. trivernolin weight. [ABSTRACT FROM AUTHOR]

Linum mucronatum seed oil contains 15% ricinoleic [(+)-12-D-hydroxy- cis-9-octadecenoic] acid, previously unknown in the Linaceae. Identification was made by IR, gas liquid chromatography, nuclear magnetic resonance, ozonolysis and mass spectrometry. Other major components of the oil are oleic acid (24%) and linoleic acid (48%). [ABSTRACT FROM AUTHOR]

Spontaneous tilting of lattice mismatched epilayers grown on (211)-oriented substrates has been observed in numerous systems in literature. Here, we have examined a model system, GaSb/Si(211), with two dimensional X-ray diffraction and conventional transmission electron microscopy, and developed a universal model which explains the origin of the tilt phenomenon as the minimization of projected lattice mismatch for low-index planes across the film/substrate interface. The model developed predicts the tilt for lattice mismatches in the range of 0%-20% covering most semiconductor heteroepitaxial systems. [ABSTRACT FROM AUTHOR]

Using confocal Raman and scanning probe microscopies, we show that the electrical properties of lateral epitaxial overgrown GaN films vary at the submicron scale. Wing regions, which are located directly above the SiO[sub x] stripes, contain carrier densities ∼10[sup 20] cm[sup -3], but possess a Fermi level deep in the band gap. This cannot be explained by having a high density of free electrons in the conduction band, but is consistent with high levels of compensation and impurity band transport. In the coalescence region, stripes of different electrical properties are evident, indicating the incorporation of impurities and defects being dictated by the growth dynamics. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this paper we present the concept, fabrication, and testing of resonant cantilever wings for monolithic micro aerial vehicles (MAVs). Combining new analytical and computational fluid dynamic work to determine the resonant mode, forces, and power of resonating curved cantilevers, we present a framework to calculate and optimize robot designs for certain figures of merit (i.e., greatest excess power, smallest size, and fastest time for a swarm to search a volume). The optimization results reveal promising designs on scales ranging from fruit flies to dragonflies with the optimal MAV having a maximum continuous travel speed of 2 m/s, 10 mm wing length, and 9 mg total mass. We then fabricate curved cantilever wings to test the theoretical model, which confirm the resonant frequency, resonant mode shape, power dissipated, and net force generated. This work is the first demonstration of asymmetric force from a symmetric flapping cycle and of the feasibility of curved cantilever wings for completely monolithic MAVs. [ABSTRACT FROM AUTHOR]

Demonstrates the Casimir effect in microelectromechanical systems. Use of micromachined torsional device; Dependence of the rotation angle on the separation between surfaces; Result of the attraction between a polysilicon plate a spherical metallic surface.

The authors have developed a process for fabricating fully enclosed single crystal InP freestanding membranes using entirely front side processing. A multilayer lattice matched InP/InGaAs heterosystem incorporating a 500 Å membrane layer was grown by molecular beam epitaxy followed by two step surface patterning, first for the support structure and then for the membrane structure definition. Membranes with lateral dimensions ranging from 1 to 10 μm have been fabricated using optical and electron beam lithography. The process is easily scalable, limited only by the ability of the membrane layer to act as an effective etch stop, i.e., ∼30 Å. [ABSTRACT FROM AUTHOR]

The initial growth stages of GaSb epilayers on Si substrates and the role of the AlSb buffer layer were studied by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Heteroepitaxy of GaSb and AlSb on Si both occur by Volmer-Weber (i.e., island mode) growth. However, the AlSb and GaSb islands have distinctly different characteristics as revealed through an atomic-resolution structural study using Z-contrast of HAADF-STEM imaging. While GaSb islands are sparse and three dimensional, AlSb islands are numerous and flattened. The introduction of 3D island-forming AlSb buffer layer facilitates the nucleation of GaSb islands. The AlSb islands-assisted nucleation of GaSb islands results in the formation of drastically higher quality planar film at a significantly smaller thickness of films. The interface of the AlSb and GaSb epilayers with the Si substrate was further investigated with energy dispersive X-ray spectrometry to elucidate the key role of the AlSb buffer layer in the growth of GaSb epilayers on Si substrates. [ABSTRACT FROM AUTHOR]

We examine the role of vicinal surface steps in the formation and propagation of twins during the growth of epitaxial III-V thin films (GaAs, InP, GaSb, AlSb) on silicon substrates. This is achieved through the combined use of two-dimensional X-ray diffraction and conventional transmission electron microscopy techniques, which allow for both a macro and nano/micro characterization of the material systems. Observed is a systematic suppression of twins formed opposite to the tilt direction of vicinal substrates through a process of step-flow overgrowth of nucleated twins, and an enhancement of twins toward the tilt direction when the fastest growth planes are aligned with the step-flow. These results indicate a probable path to the enhancement of the electronic mobility of lateral devices based on III-V semiconductors on silicon. [ABSTRACT FROM AUTHOR]

The interfacial misfit (IMF) dislocation array of an epitaxial GaSb film on a Si substrate has been imaged with high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The mismatch strain accommodation through dislocation formation has been investigated using geometric phase analysis (GPA) on HAADF-STEM images with atomic resolution to probe the defects' local strain distribution. These measurements indicate that the lattice parameter of the epitaxial film recovers its bulk value within three unit cells from the interface due to the relaxation through IMF dislocations. The atomic number contrast of the HAADF-STEM images and energy dispersive x-ray spectrometry illustrate the formation of islands of AlSb buffer layer along the interface. The role of the AlSb buffer layer in facilitating the GaSb film growth on Si is further elucidated by investigating the strain field of the islands with the GPA. [ABSTRACT FROM AUTHOR]

The atomic-resolved reversal of the polarity across an antiphase boundary (APB) was observed in GaSb films grown on Si by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The investigation of the interface structure at the origin of the APB reveals that coalescence of two domains with Ga-prelayer and Sb-prelayer causes the sublattice reversal. The local strain and lattice rotation distributions of the APB, attributed to the discordant bonding length at the APB with the surrounding GaSb lattice, were further studied using the geometric phase analysis technique. The crystallographic characteristics of the APBs and their interaction with other planar defects were observed with HAADF-STEM. The quantitative agreement between experimental and simulated images confirms the observed polarities in the acquired HAADF-STEM data. The self-annihilation mechanism of the APBs is addressed based on the rotation induced by anti-site bonds and APBs' faceting. [ABSTRACT FROM AUTHOR]

A GaSb film was grown on a Si(211) substrate using molecular beam epitaxy indicating full lattice relaxation as well as full lattice registration and dislocation-free growth in the plane perpendicular to the [01 - 1]-direction. Heteroepitaxy of GaSb on a Si(211) substrate is dominated by numerous first order and multiple higher order micro-twins. The atomic-resolved structural study of GaSb films by high-angle annular dark-field scanning transmission electron microscopy reveals that slight tilt, along with twinning, favors the lattice registry to Si(211) substrates. Preferential bonding of impinging Ga and Sb atoms at the interface due to two distinctive bonding sites on the Si(211) surface enables growth that is sublattice-ordered and free of anti-phase boundaries. The role of the substrate orientation on the strain distribution of GaSb epilayers is further elucidated by investigating the local change in the lattice parameter using the geometric phase analysis method and hence effectiveness of the lattice tilting in reducing the interfacial strain was confirmed further. [ABSTRACT FROM AUTHOR]

Unambiguous identification of anti-phase boundaries (APBs) in heteroepitaxial films of GaSb grown on Si has been so far elusive. In this work, we present conventional transmission electron microscopy (TEM) diffraction contrast imaging using superlattice reflections, in conjunction with convergent beam electron diffraction analysis, to determine a change in polarity across APBs in order to confirm the presence of anti-phase disorder. In-depth analysis of anti-phase disorder is further supported with atomic resolution high-angle annular dark-field scanning transmission electron microscopy. The nature of APBs in GaSb is further elucidated by a comparison to previous results for GaAs epilayers grown on Si. [ABSTRACT FROM AUTHOR]

The reverse bias leakage current in macroscopic GaN Schottky diodes is found to be insensitive to barrier height. Using a scanning current-voltage microscope, we show that the reverse bias current occurs at small isolated regions, while most of the sample is insulating. By comparing the current maps to topographic images and transmission electron microscopy results, we conclude that reverse bias leakage occurs primarily at dislocations with a screw component. Furthermore, for a fixed dislocation density, the V/III ratio during the molecular beam epitaxial growth strongly affects reverse leakage, indicating complex dislocation electrical behavior that is sensitive to the local structural and/or chemical changes. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]