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BACKGROUND: Ultrasound-guided needle placement has revolutionized the thoracic paravertebral block technique and can be applied in thoracoscopic surgery. OBJECTIVE: This study investigated the median effective volume (EV50) of an ultrasound-guided single shot of 0.3% ropivacaine used as a thoracic paravertebral nerve block for the radical thoracoscopic resection of lung cancer. METHODS: A total of 27 patients who received a single shot of ultrasound-guided thoracic paravertebral nerve block and underwent radical thoracoscopic resection of lung cancer were enrolled in this study between February 10 and August 13, 2018. All patients were rated as ASA grades I or II. Using ultrasound as a guide, the block needle was gradually pushed through the lateral costotransverse ligaments to the thoracic paravertebral space by the in-plane technique. After confirming the absence of blood or cerebrospinal fluid, 1–2 ml of 0.3% ropivacaine hydrochloride was injected to confirm that the position of the needle was appropriate, and a pre-determined volume of 0.3% ropivacaine hydrochloride was then administered to the patients. Sensory testing by pinprick was performed every 5 minutes for 30 minutes following the thoracic paravertebral block injection to identify the time segments during which the loss of sensation to the pinprick and its blocking effect occurred. RESULTS: All patients completed the study and 14 (51.8%) had a successful block. CONCLUSION: The EV50 of 0.3% ropivacaine was 18.46 ml (95% CI 17.09–19.95 ml) and the EV95 was 20.89 ml.

Studies on durability of cementitious materials have focused on harsh environments, but less attention has been paid to low thermal loading situations. In this paper, with the aim of exploring the evolution of internal pore pressure and microcrack extension of cementitious under low thermal environment, cement paste specimens with thermal environment slightly below 100 °C and three water–binder ratios (0.4, 0.45 and 0.5) and four fly ash admixtures (0, 10%, 20% and 30%) were designed. Firstly, the internal pore pressure of the cement paste was tested; secondly, the average effective pore pressure of the cement paste was calculated; and finally, the phase field method was used to explore the expansion of microcracks inside the cement paste when the temperature gradually increased. It was found that the internal pore pressure of the paste showed a decreasing trend as the water–binder ratio and fly ash admixture increased, and the numerical simulation found that the sprouting and development of cracks were delayed when 10% fly ash was added to the cement paste, which was consistent with the experimental results. This work provides a basis for the durability development of concrete under low thermal environment.

We present optical frequency combs with a spectral emission of 48 cm-1 and an output power of 420 mW based on a single-core quantum cascade laser at λ~8.7 μm. A flat top spectrum sustains up to 130 comb modes delivering ~3.2 mW of optical power per mode, making it a valuable tool for dual comb spectroscopy. The homogeneous gain medium, relying on a slightly-diagonal bound-to-continuum structure, promises to provide broad and stable gain for comb operating. Remarkably, the dispersion of this device is measured within 300 fs2/mm to ensure stable comb operation over 90% of the total current range. The comb is observed with a narrow beatnote linewidth around 2 kHz and has weak dependence on the applied current for stable comb operation.

The Xinlin ophiolite, located in the Great Xing’an Range domain of the Central Asian Orogenic Belt (CAOB), is considered to represent a fragment of an oceanic plate. The ophiolite consists of several discontinuous blocks composed dominantly of serpentinized ultramafic rocks with subordinate cumulate gabbros, basalts, and diabase dikes, which are intruded by younger leucogranite dikes. Here we characterize the geochemical features and formation age of the ophiolite. The ultramafic rocks are dominated by harzburgite with minor dunite, and are enriched in large-ion lithophile elements (LILEs) and light rare earth elements (LREEs), consistent with remnants of oceanic mantle. The mafic rocks show depletion in some high-field-strength elements (HFSEs) and have relatively low TiO2 and MgO contents, and likely originated from an E-MORB-like source in a back-arc setting. This suggests that the ophiolite is of supra-subduction zone (SSZ) origin. The cross-cutting leucogranite dikes, most of which are trondhjemitic, have high Al2O3 contents, low K2O/Na2O ratios, and negative zircon eHf(t) values (-8.5 to -3.8; average = -5.8), which are features distinct to other granites (e.g., fractionation-, shear-, and subduction-types) within the ophiolite and to coeval granitoids in the northern Great Xing’an Range. Zircon U-Pb dating on samples of gabbro and a leucogranite dike yielded ages of ca. 480 and 324 ± 1 Ma, respectively, suggesting that the ophiolite formed in the Early Ordovician and was emplaced at ca. 320 Ma. Together with the ages of ca. 480 Ma for the Duobaoshan arc and ca. 340 Ma for subduction-related high-Mg diorites, we suggest that ophiolite formation was probably related to the opening of an Ordovician back-arc basin, whereas formation of the younger leucogranite dikes was probably related to closure of the back-arc basin.

In this study, we report three Neoproterozoic ophiolitic melanges in the Ali River (Jifeng-Gaxian-Huanerku) area from the northern Great Xing’an Range, NE China. Detailed field mapping reveal that all three melanges disperse in a strongly sheared metasedimentary matrix composed mainly of mica-schist, quartz-schist and marble. These melanges, which have undergone polyphase deformation with northwest-verging nappe structures, are composed of a suite of amphibolite-facies mafic to ultramafic blocks including serpentinite, olivine pyroxenite, pyroxenite, diabase, gabbro and basalt. Lithological and geochemical characteristics of these ultramafic-mafic rocks suggest that their protoliths were from an ophiolitic melange formed in a Neoproterozoic supra-subduction zone. The protolith ages were constrained by LA-ICP-MS/SHRIMP U-Pb dating of zircons from the Jifeng gabbro, the Gaxian pyroxenite, and the Huanerku gabbro, which yielded ages of 647 ± 5, 628 ± 10 and 697 ± 3 Ma, respectively. The zircons from the gabbros have obvious positive eHf (t) values that range from +8.3 to +17.2 (average = +13.5) with corresponding TDM1 ages of ca. 680 Ma, indicating that these rocks are the remnants of juvenile crust derived from depleted mantle in the Neoproterozoic. All rock types in the melange underwent amphibolite facies metamorphism. The tectonic emplacement of these ophiolitic melanges was no later than 557 ± 2 Ma, which is the age of continental arc-type granodiorites (negative eHf (t) values from -7.4 to -17.8) that intruded these rocks. The mafic-ultramafic rocks in the Ali River melanges are interpreted to be fragments of a ca. 690–620 Ma supra-subduction zone ophiolite that was incorporated into the Xinlin-Xiguitu suture zone during subduction-accretion. Together with the ca. 500 Ma Toudaoqiao blueschists, the Ali River ophiolitic melange in the northern Great Xing’an Range provides important evidence for the Neoproterozoic subduction-accretion-collision processes associated with the amalgamation of the Erguna and Xing’an blocks.

Coir mat reinforced unsaturated polyester composites have been prepared and the impact toughness has been researched, and the impact toughness model has been established based on the coir weight percentage content, the change laws of each mechanical index have been detailed, thus the optimal solutions have been put forward when the coir content was from 10 wt.% to 35 wt.%. The toughening effect of coir mat on unsaturated polyester matrix is remarkable, the non-woven needle mat of coir as the reinforced body for unsaturated polyester matrix is better than that of random distribution coir form.

Coir fiber is one of the tropical fruit fibers, the effective use of coir is not comprehensive now and the phenomenon of resources waste still exists. Full study of the advantage characteristics of coir has important significance for the expansion of the application field of coir resources. This article determines the light porous characteristics of coir from the micro-morphological characteristics. Through the prediction model research of the sound absorption coefficient of the porous fiber materials, the optimization density and the optimization thickness ranges can be got for the coir density board, so as to guide the optimization design of the sound absorption performance of coir density board. The changing rule of the sound absorption coefficient of the coir density board has been got by adopting the wave impedance tube method and the sound absorption coefficients by adding 5cm air gap has also been researched. The results of the experiments confirm that coir density board can be used as a secondary noise absorption material; the practical applications of coir density board are as the lightweight wall, the car interior trim or seat filling materials and the shipping cabins materials, to reduce the corresponding environment noise.

We examine the impact of the global financial crisis (GFC) on auditor behaviour in Australia. Using a sample of listed companies, we examine whether the GFC impacted the propensity of auditors to issue going concern modifications and increased audit effort as reflected in audit fees and audit reporting lag. Controlling for client characteristics, we find an increase in the propensity to issue going concern opinions during the period 2008–2009 compared with the period 2005–2007 and that Big N auditors responded to the GFC earlier than non-Big N auditors. In relation to audit effort, we find evidence of increased audit fees during the period 2008–2009 compared with the period 2005–2007. There is, however, no evidence of increased audit reporting lags during the GFC.

Application of stress wave testing methods can realize non-destructive testing of composites, but non-homogeneous characteristics of composites determine the complexity of stress wave propagation. Using the stress wave theory to explain the propagation principle, to describe the stress situation in the composites, which is meaningful to perfect the stress wave testing method. In this paper, stress wave propagation principle of non-homogeneous laminated composites has been revealed, mathematical descriptions of stress wave propagation are also given, and finite element simulation method has been used to verify the theory.

In this article, a novel hexagon substrate integrated waveguide (SIW) dual-band filter is presented.First, the formula for calculating the resonant frequency of the dominant mode in triangle SIW cavity is given, then the triangle SIW cavity is used to construct a novel hexagon filter, which reduces the size effectively. According to the extracted-pole technique using a parallel resonant circuit at the input and output resonator, a dual-band filter with two passbands at 9.6–9.85 and 10.15–10.4 GHz has been designed and fabricated. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:562–565, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25799

OGtree is a web-based tool for constructing genome trees of prokaryotic species based on a measure of combining overlapping-gene content and overlapping-gene order in their whole genomes. The overlapping genes (OGs) are defined as adjacent genes whose coding sequences overlap partially or entirely. In fact, OGs are ubiquitous in microbial genomes and more conserved between species than non-OGs. Based on these properties, it has been suggested that OGs can serve as better phylogenetic characters than non-OGs for reconstructing the evolutionary relationships among microbial genomes. OGtree takes the accession numbers of prokaryotic genomes as its input. It then downloads their complete genomes from the National Centre for Biotechnology Information and identifies OGs in each genome and their orthologous OGs in other genomes. Next, OGtree computes an overlapping-gene distance between each pair of input genomes based on a combination of their OG content and orthologous OG order. Finally, it utilizes distance-based methods of building tree to reconstruct the genome trees of input prokaryotic genomes according to their pairwise OG distance. OGtree is available online at http://bioalgorithm.life.nctu.edu.tw/OGtree/.

From first principle calculations, we demonstrate that LiXS2 (X = Ga, In) compounds have potential applications as cathode materials for Li ion batteries. It is shown that Li can be extracted from the LiXS2 lattice with relatively small volume change and the XS4 tetrahedron structure framework remains stable upon delithiation. The theoretical capacity and average intercalation potential of the LiGaS2 (LiInS2) cathode are 190.4 (144.2) mAh/g and 3.50 V (3.53 V). The electronic structures of the LiXS2 are insulating with band gaps of 2.88 eV and 1.99 eV for X = Ga and In, respectively. However, Li vacancies, which are formed through delithiation, change the electronic structure substantially from insulating to metallic structure, indicating that the electrical conductivities of the LiXS2 compounds should be good during cycling. Li ion migration energy barriers are also calculated, and the results show that Li ion diffusions in the LiXS2 compounds can be as good as those in the currently widely used electrode materials.

It is a great challenge for information technology that how to organize and manage large amount of document data, and find users' interested information quickly and exactly. Text classification can achieve the goal of information distributaries and solve the problem of information disorder, and then it can offer the convenience to users to make decisions. Centroid classifier is one of the most efficient models. Firstly the paper expatiates on the disadvantage of traditional weight calculation method applied in text classification, and then a new method which uses feature selection evaluation function value as a factor to term frequency is proposed. This paper present an improved centroid classifier based on feedback. The main idea of the algorithm is using the misfit samples in the training set to modify the center vectors which are related with them. From test results, the algorithm proposed by the paper is valid.

By means of strongly semi-preopen L-sets and their inequality, a new countable SSP-compactness and a new SSP-Lindelof property are introduced in L-topological spaces, where L is a complete De Morgan algebra. This new form does not depend on the structure of basis lattice L and L does not require any distributivity.

A dual-band substrate integrated waveguide (SIW) filter is designed in this paper. This design is based on the frequency transformation from the normalized frequency domain to the actual frequency domain, which can calculate the coupling coefficients and the external quality factors analytically. In the realization, the dual-band resonator is utilized to replace each capacitance in the low-pass prototype circuit as the building block of the dual-band filter. To validate the method, a practical SIW dual-band filter is designed and fabricated with passbands at 5.85–5.95GHz and 6.05–6.15GHz, respectively, which has a maximum return loss of 15 dB in each passband.

By means of strongly semi-preopen L-sets and their inequality, a new form of SSP-closedness is introduced in L-topological spaces, where L is a complete De Morgan algebra. This new form does not depend on the structure of basis lattice L and L does not require any distributivity.

The general crawler provides a great many help to people for finding information in Web. However, it has some drawbacks in terms of precision and efficiency because of it's generality and no specialty. Blog, as an emerging phenomenon of the Internet, has been concerned by more and more people. We propose a new algorithm of blog-oriented web crawler through considering "Blog" as a special "topic". From the result of experiments, our blog-oriented blog crawler is superior to the generic crawler.

The problem of word mismatch is fundamental to informationretrieval. The primary goal of this paper is effectively solve theabove-mentioned problem by presenting a novel approach to queryexpansion to LSA and factor analysis, that has a solid statisticalfoundation, called PLSA, since it is based on the likelihoodprinciple and defines a proper generative model of the data.Theexperiment result on TREC data collection shows the method proposedby the paper is effective.

The generic crawler provides more help to people for finding information in WWW. However, it has some drawback in terms of precision and efficiency because of its generality and no specialty. In this paper, we address two issues of the topical web crawler. One is how to make the definition of the topic; the other is how to sort of links to be downloaded in the queue efficiently. It aims to visit only relevant pages, and get a great scale of hyperlinks which link to the relevant pages. The crawl method in this paper is a novel one, which is based on the semi-structured features of the website and content information. The results of experiment show that it is a very effective method for focused crawler.