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Summary: Erector spinae plane block and paravertebral block can provide analgesia for abdominal surgery. It is unclear whether erector spinae block is inferior to paravertebral block. We aimed to determine whether sufentanil dose and pain intensity (11‐point scale) to 24 h after erector spinae block exceeded those after paravertebral block by no more than 5 μg and 1 point, respectively. We randomly allocated 166 adults to 0.4 ml.kg−1 ropivacaine 0.375% before scheduled laparoscopic nephroureterectomy, 83 each to erector spinae or paravertebral injection. We measured incision pain and intra‐abdominal pain at rest and on movement 0.5 h, 2 h, 6 h, 18 h, 24 h and 48 h after surgery. Median (IQR [range]) cumulative sufentanil dose after erector spinae block was 15 (5–30 [0–105]) μg vs. 20 (10–50 [0–145]) μg after paravertebral block, median (95%CI) difference 5 μg (0–10), erector spinae non‐inferiority p < 0.001. Median (IQR [range]) pain were 1.5 (1.0–2.0 [0.0–5.3]) after erector spinae block vs. 2.0 (1.0–2.5 [0.0–6.0]) after paravertebral block, median (95% CI) difference 0.3 (0.0–0.5), erector spinae non‐inferiority p < 0.001. Adverse events did not differ between groups. Erector spinae block analgesia was not inferior to paravertebral block analgesia after laparoscopic nephroureterectomy. [ABSTRACT FROM AUTHOR]

Background: Vitamin D is important for maintaining physiological functions including cognition and its deficiency is associated with the occurrence of cognitive impairment. This study was to explore the association between preoperative vitamin D status and the occurrence of postoperative cognitive dysfunction (POCD) in elderly patients undergoing major surgery.Methods: This was a predefined exploratory sub-analysis of one-centre data from a randomized controlled trial. In all, 123 elderly (≥ 65 years) patients who were scheduled to undergo major cancer surgery were recruited. Serum 25-hydroxyvitamin D concentration was measured before surgery. In total, 59 nonsurgical control subjects with comparable age and education level were also enrolled. A battery of neuropsychological tests was administered the day before and the 7th day after surgery in patients or at the same time interval in control subjects. POCD was diagnosed according to the ISPOCD1 definition.Results: 71.5% (88/123) of elderly patients had vitamin D deficiency (serum 25-hydroxyvitamin D concentration < 12 ng/ml) before surgery; 24.4% (30/123) of them developed cognitive dysfunction at 1 week after surgery. After adjusting for confounding factors, high preoperative serum 25-hydroxyvitamine D concentration was related to a decreased risk of POCD (odds ratio [OR]: 0.829, 95% confidence interval [CI]: 0.708-0.971; P = 0.020), whereas preoperative vitamin D deficiency was associated with an increased risk of POCD (OR: 8.427, 95% CI: 1.595-44.511; P = 0.012).Conclusions: Vitamin D deficiency is prevalent in elderly patients undergoing major cancer surgery and increases the risk of early POCD development. Whether prophylactic vitamin D supplementation can reduce POCD in the elderly deserves further study. [ABSTRACT FROM AUTHOR]

Background: Regional anaesthesia may have advantages in preserving immune function. Tumor-infiltrating lymphocytes (TILs) are considered indicators of immune response in the tumor microenvironment and used as a prognostic marker in patients after cancer surgery. This study investigated the effects of combined epidural anaesthesia on the number of TILs in patients undergoing surgery for lung adenocarcinoma.Methods: Patients undergoing radical resection for primary lung cancer were randomized to receive either combined epidural-general anaesthesia (Epi-GA) or general anaesthesia (GA) in an ongoing randomized controlled trial (ChiCTR-TRC-14004136). Excised adenocarcinoma specimens from patients enrolled between 1 June 2015 and 30 November 2015 were selected for immunohistochemical staining of CD8 and FOXP3 molecules. The numbers of positive lymphocytes were counted and expressed as the number of cells per mm2 tumor area.Results: One hundred and twenty-eight patients were recruited and randomized; 64 patients were included in immunohistochemistry analysis (37 received Epi-GA vs. 27 received GA). The number of CD8+ T cells was higher in the Epi-GA group than in the GA group (median [interquartile range]: 292.8 [198.0-418.3] vs. 204.7 [131.1-305.8], P = 0.036); whereas the number of FOXP3+ T cells was less in the Epi-GA group than in the GA group (37.6 [14.7-92.3] vs. 99.8 [68.9-168.3], P < 0.001).Conclusions: For patients undergoing surgery for lung adenocarcinoma under general anesthesia, use of epidural anaesthesia increased CD8+ T cells infiltration but decreased FOXP3+ T cells accumulation in tumor tissues. Epidural anaesthesia may affect TILs in a manner that preserves immune function. [ABSTRACT FROM AUTHOR]

Odorant-binding proteins ( OBPs) are important components in insect olfactory systems that transport semiochemicals through the aqueous sensillum lymph to surface of olfactory receptor neurons. In this study, we cloned the c DNA of odorant-binding protein 2 ( Bhor OBP2) in Batocera horsfieldi ( Hope) and measured the level of the Bhor OBP2 m RNA in a variety of tissues using quantitative reverse transcription and real-time polymerase chain reaction. We found that the Bhor OBP2 m RNA was primarily expressed in the antennae, the level of Bhor OBP2 m RNA was higher in males than in females, and correlated with age and mating status. The Bhor OBP2 m RNA was also expressed in the labial palps at relatively high level, suggesting that it might have a role in gestation as well. To better understand the functions of the Bhor OBP2 protein in odorant reception, recombinant Bhor OBP2 was expressed in Escherichia coli, and the binding specificity of the protein for 18 volatile developmentally relevant chemicals and host-plant-related metabolites were assessed using N-phenyl-1-naphthylamine as a fluorescent probe. Competitive fluorescence binding assays showed that Bhor OBP2 bound a broad range of host-plant-related odorants, including ( E)-2-hexenal, 2-methyl-butanal, salicylaldehyde, (1 S)-(-)-verbenone, ( Z)-3-hexen-1-ol, ( E)-2-hexen-1-ol, β-pinene and ethyl acetate. Our results imply that Bhor OBP2 might play an important role in the selectivity and specificity of odorant reception. [ABSTRACT FROM AUTHOR]

The pathophysiology of post-operative cognitive dysfunction remains unclear and there is no widely accepted animal model that can simulate its occurrence. The purpose of this study was to explore the effects of surgical stress on long-term post-operative memory function in mice of different ages. Healthy C57Bl/6J male mice, of either 4- or 16-month-old, were each randomly divided into three subgroups. (1) Control group: neither anesthesia nor surgery was performed; (2) Anesthesia group: general anesthesia was administrated, surgery was not performed; (3) Surgery group: two-thirds partial hepatectomy was completed in about 15 min under general anesthesia. Morris water maze test was performed after 30 days. In mice of both month-ages, the escape latencies as well as the swimming distances decreased significantly across training days ( P<0.001). In 4-month-old mice, there were no significant differences among three subgroups. In 16-month-old mice, the escape latency was significantly less in the surgery group than in the control group ( P=0.001), and the swimming distance was significantly shorter in the surgery group than in the control and the anesthesia groups ( P=0.001 and 0.047, respectively). In the spatial probe test, time spent in the target quadrant was significantly longer in the surgery group than in the combined control and anesthesia group ( P=0.037). Partial hepatectomy did not produce significant long-term effects on memory function in 4-month-old mice. However, it significantly improved long-term memory function in 16-month-old mice. [ABSTRACT FROM AUTHOR]

This article describes a robust method for locating the poles of the spectral-domain Green's functions in a lossless or lossy multilayered medium. Real-coded genetic algorithm (RGA) is first introduced to approximate the locations of the surface- and/or leaky-wave poles and then followed by a Cauchy's integral theorem to rapidly refine the poles and remove the unwanted ones. Numerical examples demonstrate the accuracy and efficiency of the method. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1929–1934, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24472 [ABSTRACT FROM AUTHOR]

Several Krylov subspace iterative algorithms are compared as the solvers for the discrete dipole approximation method to analyze the electromagnetic scattering problem. Fast Fourier transform technique is exploited to accelerate the computation of matrix-vector product. Numerical examples for homogeneous spheres indicate that the results of radar cross section agree well with the exact solutions. Some misleading concepts in literatures are clarified. We give a new comparison of the computational complexities of these methods. Faster solvers are recommended according to the size of scatterer. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1741–1746, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21760 [ABSTRACT FROM AUTHOR]

When the sparse-matrix/canonical grid (SMCG) method is applied to analyse scattering of randomly positioned dielectric spheroids, the impedance matrix is decomposed into a strong interaction matrix and a weak interaction matrix. The strong interaction portion of the matrix–vector multiplication is computed directly as the moment method (MOM). The far-interaction portion of matrix–vector multiplication is computed indirectly using fast Fourier transforms by a Taylor series expansion of impedance matrix elements about the canonical grid point. However, the condition number of the impedance matrix obtained from the SMCG method becomes large compared to the one from MOM. As a result, the conjugate gradient (CG) method converges slowly. To attack such a trouble, the generalized product-type method based on Bi-CG (GPBi-CG) is used as an iterative solver in this paper. The numerical results show that the GPBi-CG method can achieve good convergence improvement compared to the other iterative methods. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A combined algorithm of the edge-based finite-element method (FEM) and the short-open calibration (SOC) technique is presented in order to analyze periodic structures. The computational domain is reduced to a unit cell through the use of waveguide simulators. To accurately predict the characteristics of periodic structures, the SOC technique is directly accommodated into the FEM formulation and removes unwanted parasitic errors brought about by the approximation of exciting sources. The developed FEM algorithm improves the accuracy of the solution and causes the rapid convergence of iterative solvers, when compared to the FEM combined with perfectly matching layers (PMLs) or absorbed boundary conditions (ABCs). The results for some periodic structures are given to show the accuracy and rapidity of the algorithm. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 427–430, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20844 [ABSTRACT FROM AUTHOR]

Kinetic parameter estimation for most batch crystallization processes is necessary because nucleation and crystal growth kinetic parameters are often not available. The existing identification methods are generally based on simplified population balance models such as moment equations, which contain insufficient information on the crystal size distribution (CSD). To deal with these problems, a new optimization-based identification approach for general batch cooling seeded crystallization is proposed in this study. The final-time CSD is directly used for identification. A novel effective method for solving the population balance equation is developed and used to identify nucleation and growth kinetic parameters. Cooling crystallization of ammonium sulfate in water was experimentally investigated, where the concentration was measured by an on-line density meter and the final-time CSD was analyzed by a Malvern Mastersizer 2000. Kinetics for ammonium sulfate are determined based on cooling crystallization experiments. Applying these kinetics in simulation provides a good prediction of the product CSD. [ABSTRACT FROM AUTHOR]

The anisotropic media and active properties of the perfectly matched layer (PML) absorbers significantly deteriorate the finite element method (FEM) system condition and as a result, convergence of the iterative solver is substantially slowed down. To address this issue, the symmetric successive over-relaxation (SSOR) preconditioning scheme is applied to the generalized minimal residual (GMRES) for solving a large sparse and non-symmetric system of linear equations resulting from the analysis of ferrite waveguide device by use of edge-based FEM. Consequently, this preconditioned GMRES (PGMRES) approach can reach convergence ten times faster than GMRES for the typical structures. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel numerical de-embedding scheme called the short-open calibration (SOC) technique, in conjunction with the vector finite element method (FEM), has been developed to characterize two-port network of arbitrarily shaped, three-dimensional discontinuities in microwave circuits. This SOC technique is effectively implemented into the FEM for boundary truncation of the unbounded circuit structures. In such a manner, fast convergence of iterative solver for large-sparse linear matrix equations from FEM is achieved. The SOC technique is used to remove parasitic effects brought by the approximation of the impressed voltage source and also the problem of resulting consistency between the two- and three-dimensional simulations. Scattering parameters of discontinuous sections are constructed from the definition of port voltages and currents. Numerical solutions are well compared with those published in the available literatures. It is demonstrated that the features of the SOC technique are advantageous when combined with FEM for electromagnetic problems. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The multifrontal method is applied for solving a large, sparse, and unsymmetric system of linear equations resulting from the use of the edge-based finite-element method (FEM). The finite-element method combined with perfectly matched layers (PML) is given for simulation of microwave devices, and the combined algorithm of the multifrontal method is described. The electrical characteristics of typical waveguide devices such as the ferrite phase shifter and circulator are analyzed, and the calculated results are compared with those obtained from the literature. In order to demonstrate the efficiency of the multifrontal method, the computational time is compared with that of both successive overrelaxation (SOR) preconditioned conjugate-gradient (PCG) and conjugate-gradient methods (CG) for the phase shifter. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 35: 76–81, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10521 [ABSTRACT FROM AUTHOR]

This Letter, proposes an algebraic domain decomposition algorithm (ADDA) to solve large sparse linear systems derived from the vector finite-element method (FEM) for 3D electromagnetic field problems. The proposed method segments the problem into several smaller pieces, solves each subproblem by direct methods, and then reassembles the subproblem solutions together to get the global result. Block LU factorization and multifrontal method are applied to solve each subproblem for the generation of the reduced system, and iterative methods are applied to solve the reduced system. It is shown that if combined with ADDA, biconjugate gradient method (BCG) converges more rapidly than the conjugate gradient method (CG), and both of them are faster than the conventional CG method. The simulation results demonstrate that the proposed algorithm can efficiently solve large and sparse linear equations arising from the finite-element method for the electromagnetic problems involving complex media such as perfectly matched layers (PMLs), which often make the linear equation ill-conditioned. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 414–417, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10480 [ABSTRACT FROM AUTHOR]

The multifrontal method is applied for solving a large system of linear equations resulting from the use of the edge-based finite-element method (FEM). The finite-element method combined with the perfectly matched layers (PMLs) is given for the simulation of microwave filters, and the algorithm of the multifrontal method is described in detail. The reflection loss and insertion loss of several filters are analyzed as examples, and the obtained results are compared with those obtained from the literature. In order to demonstrate the efficiency of the multifrontal method, the computational time is compared with that of both the symmetric successive overrelaxation (SSOR) preconditioned conjugate-gradient (PCG) and conjugate-gradient methods (CG) for a thick-iris waveguide bandpass filer. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 465–470, 2001. [ABSTRACT FROM AUTHOR]

In this paper, a spectral–pseudospectral domain technique is presented for the full-wave analysis of a three-dimensional MMIC. This technique combines the advantages of pseudospectral method of lines with those of spectral-domain analysis. In conjunction with the cavity-resonance technique, it enables one to efficiently extract the s-parameters of three-dimensional planar circuits. To demonstrate the generality and validity of the proposed method, numerical analyses are performed for several structures such as microstrip resonators, planar transmission-line steps, and a parallel coupled-line filter. The convergence behaviors are provided for line discretization based on the pseudospectral strategy and finite difference (FD), respectively. The calculated results are compared with those published in previous literature. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 340–345, 2001. [ABSTRACT FROM AUTHOR]

In this paper, the application of the edge-based vector finite-element method combined with the short-open calibration (SOC) technique to three-dimensional microstrip discontinuity is presented. This SOC technique is directly accommodated in the FEM algorithm, and is used to truncate the computational domain. The developed FEM algorithm is applied to the modeling of microstrip discontinuities that can be segmented into two distinct sections: a static model of feedlines, and a dynamic model of circuit discontinuity. The FEM is formulated in such a way that the port voltages and currents are explicitly represented through relevant network matrices. The SOC technique is used to remove or separate unwanted parasitic errors brought by the approximation of the impressed voltage source, and also to address the problem of the resulting consistency between different simulations. Truncation of the computational domain by the SOC technique for microstrip circuits makes the iterative solvers for large-sparse linear matrix equations from the FEM converge much faster than by perfectly matching layers (PMLs). Results for microstrip discontinuities are very well compared with available publications. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 169–174, 2001. [ABSTRACT FROM AUTHOR]

In this paper, the application of the edge-based vector finite-element method combined with the short-open calibration (SOC) technique to three-dimensional waveguide discontinuity was presented. This SOC technique is directly accommodated in the FEM algorithm, and is used to truncate the computational domain. The developed FEM algorithm is applied to the modeling of dielectric-filled waveguide discontinuities that can be segmented into two distinct sections: the static model of feed lines, and the dynamic model of circuit discontinuity. The FEM is formulated in such a way that the port voltages and currents are explicitly represented through relevant network matrices. The SOC technique is used to remove or separate unwanted parasitics brought by the approximation of the impressed voltage source, as well as the problem of the resulting consistency between different simulations. Truncation of the computational domain by the SOC technique makes the iterative solvers for large sparse linear matrix equations from the FEM converge much faster than by perfectly matched layers (PML). Results for full-height/partially dielectric-filled waveguide discontinuities are very well compared with available publications. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 27: 438–444, 2000. [ABSTRACT FROM AUTHOR]