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At present, thermal simulation experiments on accumulating rules of shale gas mainly follow the conventional method, which uses powder samples as the simulation object and does not define the shale gas as retention gas. Moreover, the powder samples after simulation cannot be observed by Scanning Electron Microscopy (SEM), and thus the evolution rules of pore structure cannot be determined. A new thermal simulation experiment method for shale gas, which uses a quartz glass tube to package the sample, and the linear regression method to analysis the data has been established. The changes of gas content and microscopic pore characteristics in shale during different phases of evolution (Ro range of 0.596%-2.143%) were studied. Results show that the contents of vent gas and desorbed gas in mudstone and oil shale increase obviously in high-mature stage with temperature higher than 400℃. Combined with SEM analysis, it can be inferred that this trend may be caused by the increasing of inorganic pores and gas generated from organic matter. This method can provide change information of shale gas contents and pore characteristics during the thermal transformation, which is more suitable for the study on the shale gas exploration and development.

In this paper, we apply a fast Fourier transform (FFT) accelerated volume integral equation solver to compute the radar cross section of large-scale inhomogeneons objects. This method is related to Bojarski's k-space method and the subsequent conjugate-(CG) and biconjugate-gradient (BCG) FFT algorithms. The method developed here combines the weak-form discretization with the BCG and stabilized BCG (BCGS) solvers. We show that this method has marked improvements over related algorithms. The numerical method has been validated by Mie series for multilayer spheres and applied to some practical problems. With this method we are currently able to solve a three-dimensional problem with a volume of size 3648[[lambda].sup.3] (21.23 million unknowns) on a single workstation. Index Terms--Biconjugate-gradient-fast Fourier transform (BCG-FFT), scattering, spectral method, stabilized BCG (BCGS)-FFT, volume integral equation.

Research describing rapid computational methods for solving two dimensional acoustic scattering problems of constant density is presented. In particular conjugate gradient fast Fourier transforms are developed.

We propose the hybridization of the extended Born approximation (EBA) with the conjugate-gradient fast Fourier transform (CG-FFT) method to improve the efficiency of numerical solution of electromagnetic induction problems. This combination improves the solution efficiency in two ways. First, using the FFT in the extended Born approximation decreases the computational cost of the conventional EBA method from O([N.sup.2]) to O(N [log.sub.2] N) arithmetic operations, where N is the number of unknowns in the problem. This approach, referred to as the FFT-EBA method, applies to problems with a fairly large contrast. Secondly, using the EBA as a partial preconditioner for the CG-FFT method increases the convergence speed of the conventional CG-FFT method. This second approach, referred to as the EBA-CGFFT method, is in principle applicable to all problems with a homogeneous background, but is particularly efficient for problems with a higher contrast. Numerical experiments suggest that the combination of these two methods is more accurate and more efficient for electromagnetic induction problems. Index Terms--CG-FFT method, electromagnetic induction, extended born approximation, integral equation, preconditioning.

We review our recent efforts to apply the nonuniform fast Fourier transform (NUFFT) and related fast transform algorithms to numerical solutions of Maxwell's equations in time and frequency domains. The NUFFT is a fast algorithm to perform the discrete Fourier transform of data sampled nonuniformly (NUDFT). Through oversampling and fast interpolation, the forward and inverse NUFFT's can be achieved with O(N [log.sub.2] N) arithmetic operations, asymptotically the same as the regular fast Fourier transform (FFT) algorithms. Using the NUFFT scheme, we develop nonuniform fast cosine transform (NUFCT) and fast Hankel transform (NUFHT) algorithms. These algorithms provide an efficient tool for numerical differentiation and integration, the key in the solutions to differential equations and volume integral equations. We present sample applications of these nonuniform fast transform algorithms in the numerical solution to Maxwell's equations. Index Terms--Fast solver, integral equation, nonuniform FFT (NUFFT), numerical methods, time domain analysis.

A new compound, 11-O-(3'-O-methylgalloyl)-bergenin (1), along with 11 known compounds (2-12), has been isolated from the rhizome of Astilbe chinensis. The chemical structure of compound 1 was determined by IR, MS, and NMR spectral data. All compounds were evaluated for the cytotoxic activity in vitro, and compound 4 showed a moderate cytotoxic activity against HepG2 cells. [ABSTRACT FROM AUTHOR]

Bupleurumjeholense Nakai (Apioideae, Apiaceae), originally found in the Wuling Mountain of China, was initially described as a species but later treated as a variety of B.sibiricum Vest ex Spreng. However, researchers have recently found that it is more closely related to B.chinense DC. In this study, we conducted morphological and phylogenetic analyses as well as chromosome counting to determine the taxonomic status of B.sibiricumvar.jeholense (Nakai) Chu. Our results showed that B.sibiricumvar.jeholense and B.chinense share common features (i.e., bracteoles 5 and stem solid) that distinguish both from B.sibiricumvar.sibiricum. The chromosome number of B.sibiricumvar.jeholense was found to be the same as in B.chinense (i.e., 2n = 12), whereas the chromosome number of B.sibiricumvar.sibiricum was 64. A phylogenetic tree based on complete chloroplast genome data revealed a close relationship between B.sibiricumvar.jeholense and B.chinense . Finally, B.sibiricumvar.jeholense and B.chinense were mainly found to differ in plant height, number of stems, and middle stem leaves. Based on this evidence, we propose a new combination: Bupleurumchinensevar.jeholense (Nakai) Q.R.Liu & L.H.Wang., Competing Interests: The authors have declared that no competing interests exist., (Li-Hua Wang, Xue-Min Xu, Yi He, Quan-Ru Liu.)

Objective: To systematically study the clinical diagnosis and treatment of smooth muscle tumor in the male reproductive system., Methods: We analyzed the ultrasonographic features, pathological findings, treatment strategies and postoperative follow-up results of 5 male patients with smooth muscle tumor in the reproductive system, and reviewed other relevant literature., Results: Compared with leiomyoma, leiomyosarcoma exhibited stronger mixed echoes than the testis at ultrasonography, typical mitotic phase (> or = 2/10 HP) of tumor cells at HE staining, and significant expressions of HIF-1alpha and Glut-1 at immunohistochemistry. No relapse was observed in the 2 cases of leiomyoma during the 10-year follow-up after simple tumor resection, nor were recurrence and metastasis in another 3 cases of leiomyosarcoma during the first year after radical surgery without combined radio- and chemo-therapy., Conclusion: Primary smooth muscle tumor of the male reproductive system is difficult to be diagnosed. Ultrasonography can help to preliminarily screen leiomyosarcoma. For those with possible leiomyosarcoma, preoperative MRI and intraoperative frozen sectioning examinations are recommended for the possibility of lymphatic metastasis. Postoperative radiotherapy and chemotherapy should be chosen cautiously for those confirmed with leiomyosarcoma by pathological examination.

In our previous study, significantly high expression levels of matrix-remodeling associated 5 (MXRA5) were identified in fresh-cultured colorectal cancer (CRC) tissues compared with their normal adjacent mucosa by differential secretome analysis. Whether MXRA5 is a potential serum biomarker of CRC has not been evaluated. The aim of this study was to investigate the association between MXRA5 expression and clinicopathological characteristics of CRC patients. The MXRA5 expression levels were determined by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC) in 20 colorectal adenoma tissues, 156 CRC tissues and their corresponding adjacent normal mucosa. Relative quantity (RQ) value and immunoreactive score (IRS) were used for quantitative assessment. The staining for MXRA5 protein was mainly located in the cytoplasm of CRC cells. All CRC tissues were positively stained, with a higher expression rate (IRS>4) of 67% (105/156), and a lower expression rate (IRS≤4) of 33% (51/156). Meanwhile, their corresponding normal tissues exhibited little positive staining; the higher expression rate was 0% (0/156) and the lower expression rate was 25% (16/156). Additionally, more than half of the adenoma tissues were positively stained; the higher expression rate was 15% (3/20) and the lower expression rate was 50% (10/20). The MXRA5 protein positive staining rates were significantly correlated with the lesion sites (colon vs. rectum, 76 vs. 59%), TNM staging (I+II vs. III+IV, 56 vs. 73%) and metastasis (present vs. absent; 76 vs. 61%) with the most high positive staining rate observable in omental metastasis (82%). However, MXRA5 mRNA expression levels showed no significant differences between CRC tissues and their corresponding normal tissues, and no significant correlation between IRS and corresponding RQ value was observed. In this study, we present the first evaluation of MXRA5 protein expression in CRC tissue. Our results revealed that MXRA5 protein is aberrantly expressed in CRC tissues, and has potential value in early detection of CRC and prediction of omental metastasis.

An unprecedented dimeric triterpenoid, designated dibelamcandal A, with a six-membered ring linking two iridal type triterpenoid nuclei, was isolated from the rhizome of Belamcanda chinensis. Its structure was determined by extensive spectroscopic measurements, including IR, ESI-MS, HR-ESI-MS, and 1D and 2D NMR. It demonstrated significant molluscicide activity against Pomacea canaliculata.