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Obesity is associated with insulin resistance, a major risk factor for type 2 diabetes and cardiovascular disease. However, not all obese individuals are insulin resistant, which confounds our understanding of the mechanistic link between these conditions. We conducted transcriptome analyses on 835 obese subjects with mean BMI of 48.8, on which we have previously reported genetic associations of gene expression. Here, we selected ~320 nondiabetic (HbA1c <7.0) subjects and further stratified the cohort into insulin-resistant versus insulin-sensitive subgroups based on homeostasis model assessment-insulin resistance. An unsupervised informatics analysis revealed that immune response and inflammation-related genes were significantly downregulated in the omental adipose tissue of obese individuals with extreme insulin sensitivity and, to a much lesser extent, in subcutaneous adipose tissue. In contrast, genes related to β-oxidation and the citric acid cycle were relatively overexpressed in adipose of insulin-sensitive patients. These observations were verified by querying an independent cohort of our published dataset of 37 subjects whose subcutaneous adipose tissue was sampled before and after treatment with thiazolidinediones. Whereas the immune response and inflammation pathway genes were downregulated by thiazolidinedione treatment, β-oxidation and citric acid cycle genes were upregulated. This work highlights the critical role that omental adipose inflammatory pathways might play in the pathophysiology of insulin resistance, independent of body weight. [ABSTRACT FROM AUTHOR]

We consider the two-dimensional time-harmonic elastic wave scattering problem for an unbounded rough surface, due to an inhomogeneous source term whose support lies within a finite distance above the surface. The rough surface is supposed to be the graph of a bounded and uniformly Lipschitz continuous function, on which the elastic displacement vanishes. We propose an upward propagating radiation condition (angular spectrum representation) for solutions of the Navier equation in the upper half-space above the rough surface, and we establish an equivalent variational formulation. Existence and uniqueness of solutions at arbitrary frequency is proved by applying a priori estimates for the Navier equation and perturbation arguments for semi-Fredholm operators. [ABSTRACT FROM AUTHOR]

Background: Drug repositioning offers the possibility of faster development times and reduced risks in drug discovery. With the rapid development of high-throughput technologies and ever-increasing accumulation of whole genome-level datasets, an increasing number of diseases and drugs can be comprehensively characterized by the changes they induce in gene expression, protein, metabolites and phenotypes. Methodology/Principal Findings: We performed a systematic, large-scale analysis of genomic expression profiles of human diseases and drugs to create a disease-drug network. A network of 170,027 significant interactions was extracted from the μ24.5 million comparisons between μ7,000 publicly available transcriptomic profiles. The network includes 645 diseasedisease, 5,008 disease-drug, and 164,374 drug-drug relationships. At least 60% of the disease-disease pairs were in the same disease area as determined by the Medical Subject Headings (MeSH) disease classification tree. The remaining can drive a molecular level nosology by discovering relationships between seemingly unrelated diseases, such as a connection between bipolar disorder and hereditary spastic paraplegia, and a connection between actinic keratosis and cancer. Among the 5,008 disease-drug links, connections with negative scores suggest new indications for existing drugs, such as the use of some antimalaria drugs for Crohn's disease, and a variety of existing drugs for Huntington's disease; while the positive scoring connections can aid in drug side effect identification, such as tamoxifen's undesired carcinogenic property. From the μ37K drug-drug relationships, we discover relationships that aid in target and pathway deconvolution, such as 1) KCNMA1 as a potential molecular target of lobeline, and 2) both apoptotic DNA fragmentation and G2/M DNA damage checkpoint regulation as potential pathway targets of daunorubicin. Conclusions/Significance: We have automatically generated thousands of disease and drug expression profiles using GEO datasets, and constructed a large scale disease-drug network for effective and efficient drug repositioning as well as drug target/pathway identification. [ABSTRACT FROM AUTHOR]

We introduce a simulation method of SAW filter by using SIMULINK based on MATLAB. We choose interdigitated interdigital transducer (IIDT) filter structure as the modeling object. To fully use the advantage of calculating matrix ability of MATLAB, we adopt 10 × 10 F matrix to depict the filter and manage to reduce it to 2 × 2 F matrix, from which insertion loss is obtained. In this paper, the formation of mathematics model is analysed, and then relevant SIMULINK block models are given. At the end of the paper, the figures of insertion loss (dB) versus normalized frequency (f/f 0 ) are obtained. [ABSTRACT FROM AUTHOR]

The N7-methylated guanosine (m[sup 7]G) cap structure, which is found at the 5' ends of mature eukaryotic mRNAs, is critical to a myriad of biological processes. The twenty structures of complexes of cap nucleosides and nucleotides and methylated bases with the vaccinia virus VP39, a cap-specific RNA 2'-O-methyltransferase, which we have determined previously, have revealed the atomic basis of cap binding. The precise insertion and tight fitting of the m[sup 7]Gua moiety of the cap between two parallel aromatic residues that are spaced only 6.8 Å apart governs the high specificity of binding. Here we report the investigation of the reaction mechanism of VP39 with three capped ligands (m[sup 7]G, m[sup 7]GpppG, and m[sup 7]GpppGA[sub 3]) by fluorescence stopped-flow technique. Cap binding is a simple one-step mechanism with very fast association rate constant (∼10[sup 7] M[sup -1] S[sup -1]). Moreover, the pH dependence on the association rate constant of m[sup 7]G binding indicates that only the positively charged keto tautomer of the cap is recognized and bound. The association and dissociation rate constants and affinity constants of the three ligands do not vary greatly, demonstrating that binding is achieved almost entirely by the interactions of m[sup 7]Gua with two aromatic residues in a cation-π sandwich. [ABSTRACT FROM AUTHOR]

Examines the structure of the messenger RNA cap binding protein. Increased affinity of tryptophan substitution for cap nucleoside; Identification of cap-binding proteins; Properties of the cap nucleobase-binding slot interaction.

Endmember extraction is a primary and indispensable component of the spectral mixing analysis model applicated to quantitatively retrieve fractional snow cover (FSC) from satellite observation. In this study, a new endmember extraction algorithm, the spatial–spectral–environmental (SSE) endmember extraction algorithm, is developed, in which spatial, spectral and environmental information are integrated together to automatically extract different types of endmembers from moderate resolution imaging spectroradiometer (MODIS) images. Then, combining the linear spectral mixture analysis model (LSMA), the SSE endmember extraction algorithm is practically applied to retrieve FSC from standard MODIS surface reflectance products in China. The new algorithm of MODIS FSC retrieval is named as SSEmod. The accuracy of SSEmod is quantitatively validated with 16 higher spatial-resolution FSC maps derived from Landsat 8 binary snow cover maps. Averaged over all regions, the average root-mean-square-error (RMSE) and mean absolute error (MAE) are 0.136 and 0.092, respectively. Simultaneously, we also compared the SSEmod with MODImLAB, MODSCAG and MOD10A1. In all regions, the average RMSE of SSEmod is improved by 2.3%, 2.6% and 5.3% compared to MODImLAB for 0.157, MODSCAG for 0.157 and MOD10A1 for 0.189. Therefore, our SSE endmember extraction algorithm is reliable for the MODIS FSC retrieval and may be also promising to apply other similar satellites in view of its accuracy and efficiency.

Two new phenolic glycosides, named gnaphaffine A and B (compounds 1 and 2), were isolated from Gnaphalium affine. together with six known compounds, including caffeic acid (3), everlastoside L (4), isorhamnetin-7-O-β-D-glucopyranoside (5), quercetin- 3-O-β-D-glucopyranoside (6), scutellarein-7-O-β-D-glucoside (7) and api-genin-7-O-β-D- glucopyranoside (8). Their structures were elucidated by spectroscopic methods, including ESI-MS and 2D NMR spectroscopy (HMQC and HMBC). All compounds were evaluated for their anti-complementary activity on the classical pathway of the complement system in vitro.

Objective To compare the curative effects of neurosurgical and neurological treatment on severe basal ganglia hemorrhage, and to propose the operation indications. Methods One hundred cases according with JinGu level Ⅳ b and V were treated with operation or non⁃operation. All cases were accorded with the standard of hypertensive severe basal ganglion and thalamus hematoma level in CT imaging. SPSS 10.0 software was used for statistical analysis. Results The total case ⁃ fatality rate in operation group and non⁃operation group was 62%(62/100) and 92%(92/100), respectively (χ2 = 23.744, P = 0.000). The total case⁃fatality rate of Ⅲ -Ⅳ level in CT imaging group and Ⅰ -Ⅱ level in CT imaging group was 84.21% (32/38) and 48.39% (30/62), respectively (P = 0.000). The total case ⁃ fatality rate in craniotomy operation group and non ⁃craniotomy operation group was 54.41% (37/68) and 78.13% (25/32), respectively (χ2 = 7.920, P = 0.048). Conclusion Patients with JinGu level Ⅳ b of severe basal ganglia hemorrhage should be operated actively. Patients in JinGu level Ⅴ group should be operated cautiously referred with the following factors: age (< 60 years old); brain hernia occurrence time (onset time > 12 h); level in CT imaging (Ⅰ -Ⅱ level); systemic disease [no major visceral (heart, lung, liver, kidney) disease and diabetes]. DOI：10.3969/j.issn.1672-6731.2011.02.020

This paper is concerned with the uniqueness of two inverse moving source problems in electrodynamics with partial boundary data. We show that (1) if the temporal source function is compactly supported, then the spatial source profile function or the orbit function can be uniquely determined by the tangential trace of the electric field measured on part of a sphere; (2) if the temporal function is given by a Dirac distribution, then the impulsive time point and the source location can be uniquely determined at four receivers on a sphere. [ABSTRACT FROM AUTHOR]

This work is concerned with an inverse electromagnetic scattering problem in two dimensions. We prove that in the TE polarization case, the knowledge of the electric far-field pattern incited by a single incoming wave is sufficient to uniquely determine the shape of a penetrable scatterer of rectangular type. As a by-product, the uniqueness is also confirmed to inverse transmission problems modelled by scalar Helmholtz equations with discontinuous normal derivatives at the scattering interface. [ABSTRACT FROM AUTHOR]

This paper is concerned with inverse time-harmonic acoustic and electromagnetic scattering from an infinite biperiodic medium (diffraction grating) in three dimensions. In the acoustic case, we prove that the near-field data of fixed-direction plane waves incited at multiple frequencies uniquely determine a refractive index function which depends on two variables. An analogous uniqueness result holds for time-harmonic Maxwell’s system if the inhomogeneity is periodic in one direction and remains invariant along the other two directions. Uniqueness for recovering (non-periodic) compactly supported contrast functions are also presented. [ABSTRACT FROM AUTHOR]

Assume that a bounded scatterer is embedded into an infinite homogeneous isotropic background medium in two dimensions. The refractive index function is supposed to be piecewise constant. If the scattering interface contains a weakly singular point, we prove that the scattered field cannot vanish identically. This implies the absence of non-scattering energies for piecewise analytic interfaces with one singular point. Local uniqueness is obtained for shape identification problems in inverse medium scattering with a single far-field pattern. [ABSTRACT FROM AUTHOR]

We are concerned with time-dependent inverse source problems in elastodynamics. The source term is supposed to be the product of a spatial function and a temporal function with compact support. We present frequency-domain and time-domain approaches to show uniqueness in determining the spatial function from wave fields on a large sphere over a finite time interval. The stability estimate of the temporal function from the data of one receiver and the uniqueness result using partial boundary data are proved. Our arguments rely heavily on the use of the Fourier transform, which motivates inversion schemes that can be easily implemented. A Landweber iterative algorithm for recovering the spatial function and a non-iterative inversion scheme based on the uniqueness proof for recovering the temporal function are proposed. Numerical examples are demonstrated in both two and three dimensions. [ABSTRACT FROM AUTHOR]

Consider a time-harmonic acoustic point source incident on a bounded isotropic linearly elastic body immersed in a homogeneous compressible inviscid fluid. This paper is concerned with the inverse fluid–solid interaction problem of recovering the elastic body from near-field data generated by infinitely many incident point source waves at a fixed energy. The incident point sources and the receivers for recording scattered signals are both located on a non-spherical closed surface, on which an outgoing-to-incoming operator is appropriately defined. We provide a theoretical justification of the factorization method for precisely characterizing the scatterer by utilizing the spectrum of the near-field operator. This generalizes the imaging scheme developed in (Hu et al 2014 Inverse Problems30 095005) to the case when near-field data are measured on non-spherical surfaces. Numerical examples in 2D are demonstrated to show the validity and accuracy of the inversion algorithm, even if limited aperture data are available on one or several line segments. [ABSTRACT FROM AUTHOR]

This paper is concerned with the inverse problem of detecting a boundary corrosion coefficient which describes some corrosion index from a single pair of Cauchy data measured on an accessible boundary of an electrostatic conductor in two dimensions. The corroded portion is supposed to be either a line segment or a part of some circle, while the corrosion coefficient is restricted to be an analytic or a piecewise constant function. We prove two Hölder stability estimates in recovering the unknown boundary coefficient. Our arguments rely on the Schwarz reflection principle with the Robin boundary condition and a novel interior estimate derived from the elliptic Carleman estimate. [ABSTRACT FROM AUTHOR]

Consider time-harmonic acoustic scattering problems governed by the Helmholtz equation in two and three dimensions. We prove that bounded penetrable obstacles with corners or edges scatter every incident wave nontrivially, provided the function of refractive index is real-analytic. Moreover, if such a penetrable obstacle is a convex polyhedron or polygon, then its shape can be uniquely determined by the far-field pattern over all observation directions incited by a single incident wave. Our arguments are elementary and rely on the expansion of solutions to the Helmholtz equation. [ABSTRACT FROM AUTHOR]

In this paper we establish a factorization method for recovering the location and shape of an acoustic bounded obstacle with using the near-field data, corresponding to infinitely many incident point sources. The obstacle is allowed to be an impenetrable scatterer of sound-soft, sound-hard or impedance type or a penetrable scatterer. An outgoing-to-incoming operator is constructed for facilitating the factorization of the near-field operator, which can be easily implemented numerically. Numerical examples are presented to demonstrate the feasibility and effectiveness of our inversion algorithm, including the case where limited aperture near-field data are available only. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the inverse problem of recovering a two-dimensional perfectly reflecting diffraction grating from the scattered waves measured above the structure. Inspired by a novel idea developed by Bao et al (Trans. Am. Math. Soc. to appear), we present a complete characterization of the global uniqueness in determining polygonal periodic structures using a minimal number of incident plane waves. The idea in this paper combines the reflection principle for the Helmholtz equation and the dihedral group theory. We characterize all periodic polygonal structures that cannot be identified by one incident plane wave, including the resonance case where a Rayleigh frequency is allowed. Furthermore, we show that those unidentifiable gratings provide non-uniqueness examples for appropriately chosen wave number and incident angles. We also indicate and fix a gap in the proof of the main theorem of Elschner and Yamamoto (2007 Z. Anal. Anwend. 26 165-77) and generalize the uniqueness results of that paper. [ABSTRACT FROM AUTHOR]