353 research outputs found
DUAL RECTANGULAR RING WITH OPEN-ENDED CPW-FED MONOPOLE ANTENNA FOR WIMAX/WLAN APPLICATIONS
Abstract—A coplanar waveguide (CPW)-fed planar monopole antenna with triple-band operation for worldwide interoperability for microwave access (WiMAX) and wireless local area network (WLAN) applications is presented. The antenna comprises dual rectangular ring with open-end. The triple operating bands with 10-dB return-loss bandwidths of about 30.8 % ranging from 2.2 to 2.97GHz, 23.4% ranging from 3.17 to 3.99GHz, and 25.4 % ranging from 4.91 to 6.31GHz, covering the required bandwidths of 2.4/5.2/5.8GHz WLAN and 3.5/5.5GHz WiMAX standards, are obtained. 1
In vivo and in vitro immunomodulatory and anti-inflammatory effects of total flavonoids of astragalus
Background: Astragali Radix has long been used to improve immune function in traditional Chinese medicine. However, its main active components and potential immunomodulatory or anti-inflammatory activities have not been elucidated. In the present study, the immunomodulatory and anti-inflammatory activities of total flavonoids of Astragalus (TFA) isolated from Astragali Radix were evaluated by using in vivo animal models and in vitro cell models.Materials and Methods: The in vivo Immunomodulatory and anti-inflammatory activities of TFA were assessed by measuring macrophage phagocytic index, delayed type hypersensitivity, serum hemolysin level and immune organ index in mice, ear edema test in mice, paw edema test in rats, vascular permeability test in mice and granuloma test in rats. The in vitro Immunomodulatory and anti-inflammatory activities of TFA were assessed by examining its effect on cytokine and mediator production in un-stimulated and LPS-stimulated murine RAW 264.7 macrophages.Results: The results of in vivo experiments showed that TFA enhanced macrophage phagocytic index, delayed type hypersensitivity, serum hemolysin level and immune organ index in mice, and attenuated mouse ear edema, rat paw edema, mouse vascular permeability and rat granuloma formation. The results of in vitro experiments showed that TFA stimulated the production of NO and cytokine TNF-α, IL-1β, IL-6 and IFN-γ in un-stimulated RAW 264.7 macrophages, and inhibited the overproduction of these inflammatory mediators in LPS-stimulated RAW 264.7 macrophages in a dose-dependent manner without exerting cytotoxicity.Conclusion: These results of this study indicate that TFA have potential immunostimulatory and anti-inflammatory effects.Key words: Total flavonoids of Astragalus (TFA), Immunomodulation, Anti-inflammation, In vivo, In vitr
Wideband Circularly Polarized SIW Antenna Array That Uses Sequential Rotation Feeding
A wideband right-handed circularly polarized (CP) substrate integrated waveguide- (SIW-) based diamond ring-slot antenna array at the X-band is presented in this study. The array consists of four elements that exhibit wideband impedance matching characteristics and good radiation performance. The array also employs a sequential rotation feeding method to achieve the wideband axial ratio (AR) bandwidth. The feeding network is based on the SIW power divider with a delay line related to sequential rotation feeding. To validate our design, an antenna array is fabricated and measured. The measured impedance and AR bandwidths are 19.2% (VSWR<2) and 14.1% (AR<3 dB), respectively. Moreover, the antenna has a stable CP peak gain of more than 12 dBic from 10.1 GHz to 10.7 GHz
Studies on Anti-Depressant Activity of Four Flavonoids Isolated from Apocynum venetum Linn (Apocynaceae) Leaf in Mice
Purpose: To investigate the anti-depressant activity of kaempferol, quercetin, kaempferol-3-O-β-Dglucose and quercetin-3-O-β-D-glucose isolated from Apocynum venetum Linn. (Apocynaceae) leaf and their mechanisms of action.Methods: The four flavonoids were isolated from Apocynum venetum leaf by chromatography. Mice were divided into vehicle, fluoxetine, kaempferol, quercetin, kaempferol-3-O-β-D-glucose and quercetin- 3-O-β-D-glucose groups (n = 10). Forced swimming (FST), tail suspension (TST) and locomotor activity (LAT) tests were used to evaluate the effects of the four flavonoids (0.35 mM/kg) on immobility time, monoamine neurotransmitters, viz, norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5- HT), as well as on the metabolite (5-HIAA) in mice brain and central nervous system (CNS) with the aid of video camera, HPLC-ECD and activity-monitoring system.Results: The four flavonoids significantly (p < 0.05) reduced mice immobility time (72.58 - 90.24; 52.58 - 70.24 s), 5-HIAA levels (940.8 - 1244.7; 880.8 - 1164.1 ng/g) and 5-HIAA/5-HT ratio (1.77 - 4.76; 1.83 - 4.16), but increased NE, DA and 5-HT levels (238.7 - 405.7, 308.4 - 528.1, 261.4 - 531.9; 243.9 - 423.6, 296.7 - 534.9, 279.8 - 481.4 ng/g) in FST and TST, compared with control group (146.18, 126.18 s; 1363.4, 1240.9 ng/g; 7.43, 6.16; 138.4, 235.4, 183.4 and 143.7, 218.6, 201.4 ng/g). The effects of the four flavonoids on the above indices were significant (p < 0.05) and positively related to their polarity. They had no CNS-stimulating effects in LAT.Conclusion: The anti-depressant activities of the four flavonoids are positively related to their polarity, and the mechanisms may be due to increased NE, DA and 5-HT and reduced 5-HT metabolism.Keywords: Kaempferol, Quercetin, Forced swimming test, Tail suspension test, Locomotor activity test, Neurotransmitter
The impact of single nucleotide polymorphism in monomeric alpha-amylase inhibitor genes from wild emmer wheat, primarily from Israel and Golan
<p>Abstract</p> <p>Background</p> <p>Various enzyme inhibitors act on key insect gut digestive hydrolases, including alpha-amylases and proteinases. Alpha-amylase inhibitors have been widely investigated for their possible use in strengthening a plant's defense against insects that are highly dependent on starch as an energy source. We attempted to unravel the diversity of monomeric alpha-amylase inhibitor genes of Israeli and Golan Heights' wild emmer wheat with different ecological factors (e.g., geography, water, and temperature). Population methods that analyze the nature and frequency of allele diversity within a species and the codon analysis method (comparing patterns of synonymous and non-synonymous changes in protein coding sequences) were used to detect natural selection.</p> <p>Results</p> <p>Three hundred and forty-eight sequences encoding monomeric alpha-amylase inhibitors (WMAI) were obtained from 14 populations of wild emmer wheat. The frequency of SNPs in WMAI genes was 1 out of 16.3 bases, where 28 SNPs were detected in the coding sequence. The results of purifying and the positive selection hypothesis (p < 0.05) showed that the sequences of WMAI were contributed by both natural selection and co-evolution, which ensured conservation of protein function and inhibition against diverse insect amylases. The majority of amino acid substitutions occurred at the C-terminal (positive selection domain), which ensured the stability of WMAI. SNPs in this gene could be classified into several categories associated with water, temperature, and geographic factors, respectively.</p> <p>Conclusions</p> <p>Great diversity at the WMAI locus, both between and within populations, was detected in the populations of wild emmer wheat. It was revealed that WMAI were naturally selected for across populations by a ratio of dN/dS as expected. Ecological factors, singly or in combination, explained a significant proportion of the variations in the SNPs. A sharp genetic divergence over very short geographic distances compared to a small genetic divergence between large geographic distances also suggested that the SNPs were subjected to natural selection, and ecological factors had an important evolutionary role in polymorphisms at this locus. According to population and codon analysis, these results suggested that monomeric alpha-amylase inhibitors are adaptively selected under different environmental conditions.</p
Characterization and comparative analysis of HMW glutenin 1Ay alleles with differential expressions
6-Methyl-2-pyridyl N-acetyl-1-thio-β-d-glucosaminide methanol monosolvate
In the title compound, C14H20N2O5S·CH4O, the pyranose and pyridine rings are linked through an S atom. The pyranose ring has a normal chair conformation. An intramolecular O—H⋯N hydrogen bond occurs. Intermolecular O—H⋯O, N—H⋯O, O—H⋯N and weak C—H⋯O hydrogen bonding is present in the crystal structure
GM-TCNet: Gated Multi-scale Temporal Convolutional Network using Emotion Causality for Speech Emotion Recognition
In human-computer interaction, Speech Emotion Recognition (SER) plays an
essential role in understanding the user's intent and improving the interactive
experience. While similar sentimental speeches own diverse speaker
characteristics but share common antecedents and consequences, an essential
challenge for SER is how to produce robust and discriminative representations
through causality between speech emotions. In this paper, we propose a Gated
Multi-scale Temporal Convolutional Network (GM-TCNet) to construct a novel
emotional causality representation learning component with a multi-scale
receptive field. GM-TCNet deploys a novel emotional causality representation
learning component to capture the dynamics of emotion across the time domain,
constructed with dilated causal convolution layer and gating mechanism.
Besides, it utilizes skip connection fusing high-level features from different
gated convolution blocks to capture abundant and subtle emotion changes in
human speech. GM-TCNet first uses a single type of feature, mel-frequency
cepstral coefficients, as inputs and then passes them through the gated
temporal convolutional module to generate the high-level features. Finally, the
features are fed to the emotion classifier to accomplish the SER task. The
experimental results show that our model maintains the highest performance in
most cases compared to state-of-the-art techniques.Comment: The source code is available at:
https://github.com/Jiaxin-Ye/GM-TCNe
Molecular evolution of dimeric α-amylase inhibitor genes in wild emmer wheat and its ecological association
<p>Abstract</p> <p>Background</p> <p>α-Amylase inhibitors are attractive candidates for the control of seed weevils, as these insects are highly dependent on starch as an energy source. In this study, we aimed to reveal the structure and diversity of dimeric α-amylase inhibitor genes in wild emmer wheat from Israel and to elucidate the relationship between the emmer wheat genes and ecological factors using single nucleotide polymorphism (SNP) markers. Another objective of this study was to find out whether there were any correlations between SNPs in functional protein-coding genes and the environment.</p> <p>Results</p> <p>The influence of ecological factors on the genetic structure of dimeric α-amylase inhibitor genes was evaluated by specific SNP markers. A total of 244 dimeric α-amylase inhibitor genes were obtained from 13 accessions in 10 populations. Seventy-five polymorphic positions and 74 haplotypes were defined by sequence analysis. Sixteen out of the 75 SNP markers were designed to detect SNP variations in wild emmer wheat accessions from different populations in Israel. The proportion of polymorphic loci <it>P </it>(5%), the expected heterozygosity <it>He</it>, and Shannon's information index in the 16 populations were 0.887, 0.404, and 0.589, respectively. The populations of wild emmer wheat showed great diversity in gene loci both between and within populations. Based on the SNP marker data, the genetic distance of pair-wise comparisons of the 16 populations displayed a sharp genetic differentiation over long geographic distances. The values of <it>P</it>, <it>He</it>, and Shannon's information index were negatively correlated with three climatic moisture factors, whereas the same values were positively correlated by Spearman rank correlation coefficients' analysis with some of the other ecological factors.</p> <p>Conclusion</p> <p>The populations of wild emmer wheat showed a wide range of diversity in dimeric α-amylase inhibitors, both between and within populations. We suggested that SNP markers are useful for the estimation of genetic diversity of functional genes in wild emmer wheat. These results show significant correlations between SNPs in the α-amylase inhibitor genes and ecological factors affecting diversity. Ecological factors, singly or in combination, explained a significant proportion of the variations in the SNPs, and the SNPs could be classified into several categories as ecogeographical predictors. It was suggested that the SNPs in the α-amylase inhibitor genes have been subjected to natural selection, and ecological factors had an important evolutionary influence on gene differentiation at specific loci.</p
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