The statistical properties of galaxy morphological types in compact groups of Main galaxies from the SDSS Data Release 4

In order to explore the statistical properties of galaxy morphological types in compact groups (CGs), we construct a random group sample which has the same distributions of redshift and number of member galaxies as those of the CG sample. It turns out that the proportion of early-type galaxies in different redshift bins for the CG sample is statistically higher than that for random group sample, and with growing redshift z this kind of difference becomes more significant. This may be due to the existence of interactions and mergers within a significant fraction of SDSS CGs. We also compare statistical results of CGs with those of more compact groups and pairs, but do not observe as large statistical difference as Hickson (1982)'results.Comment: 12 pages, 9 figure

Isolation, Identification and Determination of Six Nucleosides and Two Amino Acids from Bamboo Shoots of Gramineae Phyllostachys prominens (W Y Xiong)

Purpose: To develop a method to identify and quantify the compounds in the shoots of four Phyllostachys bamboo species (Gramineae Phyllostachys prominens W. Y. Xiong, Gramineae Phyllostachys iridescins C. Y. Yao Gramineae Phyllostachys pubescens (Carr.) Mitford, Gramineae Phyllostachys praecox C. D. Chu et C. S. Chao. ).Methods: The compounds in bamboo shoots were isolated and identified by ultraviolet (UV) spectroscopy, mass spectrometry (MS), and nuclear magnetic resonance (NMR). Quantitative analysis was performed by reversed-phase high performance liquid chromatography (RP-HPLC) using a C18 column and a mixture (1:1ratio) of acetonitrile and 15 mM ammonium acetate (pH 6.0) as mobile phase. This method was validated for its reproducibility, chemical stability, and recovery.Results: Six nucleosides and two amino acids were isolated from bamboo shoots, including guanosine, 2’-deoxyguanosine, adenosine, thymidine, uridine, cytidine, tryptophan, and phenylalanine. The HPLC method was rapid and reproducible. The intraday and interday concentrations of the eight identified compounds showed good linearity in the range of 0.22 - 60.00 μg/mL. The relative standard deviation (RSD) for intraday and interday precision for reproducibility and stability was < 3 %. The validated method was successfully applied to determine the content of the eight compounds in four different Phyllostachys species.Conclusion: Adenosine was isolated from bamboo shoots previously, but the isolation of the other seven compounds are reported here for the first time. The method proposed is sensitive and reproducible, and would facilitate studies of nutritional/medicinal compounds in bamboo shoot.Keywords: Bamboo shoots, Phyllostachys prominens, Guanosine, 2’ Deoxyguanosine, Adenosine, Thymidine, Uridine, Cytidine, Tryptophan, Phenylalanin

A Regression-Based Framework for Quantitative Assessment of Muscle Spasticity Using Combined EMG and Inertial Data From Wearable Sensors

There have always been practical demands for objective and accurate assessment of muscle spasticity beyond its clinical routine. A novel regression-based framework for quantitative assessment of muscle spasticity is proposed in this paper using wearable surface electromyogram (EMG) and inertial sensors combined with a simple examination procedure. Sixteen subjects with elbow flexor or extensor (i.e., biceps brachii muscle or triceps brachii muscle) spasticity and eight healthy subjects were recruited for the study. The EMG and inertial data were recorded from each subject when a series of passive elbow stretches with different stretch velocities were conducted. In the proposed framework, both lambda model and kinematic model were constructed from the recorded data, and biomarkers were extracted respectively from the two models to describe the neurogenic component and biomechanical component of the muscle spasticity, respectively. Subsequently, three evaluation methods using supervised machine learning algorithms including single-/multi-variable linear regression and support vector regression (SVR) were applied to calibrate biomarkers from each single model or combination of two models into evaluation scores. Each of these evaluation scores can be regarded as a prediction of the modified Ashworth scale (MAS) grade for spasticity assessment with the same meaning and clinical interpretation. In order to validate performance of three proposed methods within the framework, a 24-fold leave-one-out cross validation was conducted for all subjects. Both methods with each individual model achieved satisfactory performance, with low mean square error (MSE, 0.14 and 0.47) between the resultant evaluation score and the MAS. By contrast, the method using SVR to fuse biomarkers from both models outperformed other two methods with the lowest MSE at 0.059. The experimental results demonstrated the usability and feasibility of the proposed framework, and it provides an objective, quantitative and convenient solution to spasticity assessment, suitable for clinical, community, and home-based rehabilitation

Identification of four novel small non-coding RNAs from Xanthomonas campestris pathovar campestris

<p>Abstract</p> <p>Background</p> <p>In bacteria, small non-coding RNAs (sRNAs) have been recognized as important regulators of various cellular processes. Approximately 200 bacterial sRNAs in total have been reported. However, very few sRNAs have been identified from phytopathogenic bacteria.</p> <p>Results</p> <p><it>Xanthomons campestris </it>pathovar <it>campestris </it>(<it>Xcc</it>) is the causal agent of black rot disease of cruciferous crops. In this study, a cDNA library was constructed from the low-molecular weight RNA isolated from the <it>Xcc </it>strain 8004 grown to exponential phase in the minimal medium XVM2. Seven sRNA candidates were obtained by sequencing screen of 2,500 clones from the library and four of them were confirmed to be sRNAs by Northern hybridization, which were named sRNA-<it>Xcc</it>1, sRNA-<it>Xcc</it>2, sRNA-<it>Xcc</it>3, and sRNA-<it>Xcc</it>4. The transcription start and stop sites of these sRNAs were further determined. BLAST analysis revealed that the four sRNAs are novel. Bioinformatics prediction showed that a large number of genes with various known or unknown functions in <it>Xcc </it>8004 are potential targets of sRNA-<it>Xcc</it>1, sRNA-<it>Xcc</it>3 and sRNA-<it>Xcc</it>4. In contrast, only a few genes were predicted to be potential targets of sRNA-<it>Xcc</it>2.</p> <p>Conclusion</p> <p>We have identified four novel sRNAs from <it>Xcc </it>by a large-scale screen. Bioinformatics analysis suggests that they may perform various functions. This work provides the first step toward understanding the role of sRNAs in the molecular mechanisms of <it>Xanthomonas campestris </it>pathogenesis.</p

Plasmoid ejection and secondary current sheet generation from magnetic reconnection in laser-plasma interaction

Reconnection of the self-generated magnetic fields in laser-plasma interaction was first investigated experimentally by Nilson {\it et al.} [Phys. Rev. Lett. 97, 255001 (2006)] by shining two laser pulses a distance apart on a solid target layer. An elongated current sheet (CS) was observed in the plasma between the two laser spots. In order to more closely model magnetotail reconnection, here two side-by-side thin target layers, instead of a single one, are used. It is found that at one end of the elongated CS a fan-like electron outflow region including three well-collimated electron jets appears. The ($>1$ MeV) tail of the jet energy distribution exhibits a power-law scaling. The enhanced electron acceleration is attributed to the intense inductive electric field in the narrow electron dominated reconnection region, as well as additional acceleration as they are trapped inside the rapidly moving plasmoid formed in and ejected from the CS. The ejection also induces a secondary CS

Identification of exosome-like nanoparticle-derived microRNAs from 11 edible fruits and vegetables

Edible plant-derived exosome-like nanoparticles (EPDELNs) are novel naturally occurring plant ultrastructures that are structurally similar to exosomes. Many EPDELNs have anti-inflammatory properties. MicroRNAs (miRNAs) play a critical role in mediating physiological and pathological processes in animals and plants. Although miRNAs can be selectively encapsulated in extracellular vesicles, little is known about their expression and function in EPDELNs. In this study, we isolated nanovesicles from 11 edible fruits and vegetables and subjected the corresponding EPDELN small RNA libraries to Illumina sequencing. We identified a total of 418 miRNAs—32 to 127 per species—from the 11 EPDELN samples. Target prediction and functional analyses revealed that highly expressed miRNAs were closely associated with the inflammatory response and cancer-related pathways. The 418 miRNAs could be divided into three classes according to their EPDELN distributions: 26 “frequent” miRNAs (FMs), 39 “moderately present” miRNAs (MPMs), and 353 “rare” miRNAs (RMs). FMs were represented by fewer miRNA species than RMs but had a significantly higher cumulative expression level. Taken together, our in vitro results indicate that miRNAs in EPDELNs have the potential to regulate human mRNA

Comparative and functional genomics reveals genetic diversity and determinants of host specificity among reference strains and a large collection of Chinese isolates of the phytopathogen Xanthomonas campestris pv. campestris

Construction of a microarray based on the genome of Xanthomonas campestris pv.campestris (Xcc), and its use to analyse 18 other virulent Xcc strains, revealed insights into the genetic diversity and determinants of host specificity of Xcc strains