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Litchi (Litchi chinensis) pepper spot disease results in black spotting symptoms on litchi fruits. This disease was first observed on litchi cultivar Guiwei, in Guangzhou, China, in 2009, and then found widespread in other litchi‐growing regions of China. Colletotrichum isolates were consistently recovered from typical black spot lesions of diseased fruits with frequency ranging from 83% to 100%. Three representative Colletotrichum isolates from Maoming, Guangzhou and Shenzhen were selected for identification and pathogenicity testing in the field. Based on morphology and phylogenetic analysis using the ribosomal internal transcribed spacer region (ITS), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), calmodulin (CAL), actin (ACT), β‐tubulin (TUB2) and glutamine synthetase (GS) gene sequences, the three isolates were identified as C. siamense. In the pathogenicity experiments, typical symptoms appeared on the inoculated litchi fruits, including black spots and green patches around these black spots. These symptoms were consistent with the symptoms originally observed in the field. Colletotrichum siamense was successfully reisolated from the typical black spot lesions of the inoculated litchi fruits. To the authors' knowledge, this is the first report on characterization of C. siamense as the causal agent of litchi pepper spot disease in mainland China by successful inoculation on fruits under field conditions. [ABSTRACT FROM AUTHOR]

Considering its high carrier mobility and high saturation velocity, a low-noise amplifier is thought of as being the most attractive analogue application of graphene field-effect transistors. The noise performance of graphene field-effect transistors at frequencies in the K-band remains unknown. In this work, the noise parameters of a graphene transistor are measured from 10 to 26 GHz and noise models are built with the data. The extrinsic minimum noise figure for a graphene transistor reached 1.5 dB, and the intrinsic minimum noise figure was as low as 0.8 dB at a frequency of 10 GHz, which were comparable with the results from tests on Si CMOS and started to approach those for GaAs and InP transistors. Considering the short development time, the current results are a significant step forward for graphene transistors and show their application potential in high-frequency electronics. [ABSTRACT FROM AUTHOR]

We study the thermal light correlated interference using a He-Ne laser beam with intensities modulated by mathematical functions. Three mathematical functions are adopted: a power function f [I(x)] = I n(x); an exponential function f [I(x)] = exp[ pI(x)]; and an inverse trigonometric function f [I(x)] = tan-1[qI(x)]. Our results show that these correlation methods influence the contrast of correlated interference fringes, but not the periods of the fringes, which just depend on the relation of correlated spatial coordinates. [ABSTRACT FROM AUTHOR]

In this work, a Wheatstone bridge-type pressure sensor based on AlGaN/GaN heterostructure was fabricated for the first time. The pressure sensor consisted of four gateless high electron mobility transistors (HEMTs) on a 585 μm depth circular membrane, in which 15-μm-thick silicon substrate was left. Direct voltage readout was realized in the AlGaN/GaN pressure sensor, which exhibited a non-linearity of 0.6% with a sensitivity of 1.25 μV/kPa/V over a wide pressure range from 0.1 MPa to 5 MPa. Because of the in-plane isotropic properties, the working mechanism in the AlGaN/GaN pressure sensor is found to be quite different from the silicon-based sensor. Although the resistances of the four gateless HEMTs all increased with enlarging pressure, the changes of neighboring resistors varied with alignments under the piezoelectric effects. Finally, voltage linear readout was realized by the differential operation of Wheatstone bridge circuit. [ABSTRACT FROM AUTHOR]

Quasi-free-standing epitaxialgraphenegrown on wide band gap semiconductorSiC demonstrates high carrier mobility and good material uniformity, which make it promising for graphene-based electronic devices. In this work, quasi-free-standing bilayer epitaxialgraphene is prepared and its transistors with gate lengths of 100 nm and 200 nm are fabricated and characterized. The 100 nm gate length graphenetransistor shows improved DC and RF performances including a maximum current density Ids of 4.2 A/mm, and a peak transconductance gm of 2880 mS/mm. Intrinsic current-gain cutoff frequency fT of 407 GHz is obtained. The exciting DC and RF performances obtained in the quasi-free-standing bilayer epitaxialgraphenetransistor show the great application potential of this material system. [ABSTRACT FROM AUTHOR]

Real time information on process parameters such as residence time distribution (RTD) is essential for diagnosis and control of continuous processes. In the present paper, an improved apparatus for inline measurement of RTD of thermomechanically complex systems was developed. The apparatus possessed many important advantages over those reported in the literatures. A reference detector was added to the system to improve the resistance of the latter to both external and internal disturbances, and it had two light paths instead of one. Meanwhile, a special optical fibre probe with pressure and heat resistance was designed to obtain operating data under high pressure and high temperature circumstance. As an important use of the improved apparatus, the local residence volume distributions of turbine mixing elements were investigated under various operating conditions such as feedrate and screw speed, on the basis of inline measurement of partial RTDs. The working principle of this apparatus is expected to be suitable for various types of process equipments and chemical systems including thermomechanically complex systems. [ABSTRACT FROM AUTHOR]

Abstract: This study evaluated the plastic changes of c-jun and c-fos in the right sixth lumbar dorsal root ganglion (L6 DRG), Rexed’s lamina II in representative spinal segments L3, L5, and L6 and in the nucleus dorsalis (ND) at L3 segments after electro-acupuncture (EA) in cats subjected to removal of L1–L5 and L7–S2 DRG. Following dorsal root ganglionectomy, there was a significant increase in the density of c-jun immunoreactivity in the neurons and glia in spinal lamina II and in the ND; there was also marked elevation in the expression of c-fos in ND. In both cases there was no change in the c-jun and c-fos immunoreactivity in the DRG. After EA in the operated animals, there was an up-regulation in the expression of c-jun in the L6 DRG and the associated spinal lamina II; however, increased c-fos expression was detected only in the L6 DRG. Western blot and RT-PCR were also performed to quantitatively explore the mRNA and protein expression changes in the spinal dorsal horn and associated DRG. Following partial deafferentation, there was a significant increase in the protein level of both c-jun and c-fos in the dorsal horn, while, in both cases there was no change in c-jun and c-fos protein and mRNA in the DRG. After EA in the operated animals, both c-jun protein and its mRNA in the L6 DRG as well as the associated dorsal horn of L6 spinal segment were upregulated, but increased c-fos protein and its mRNA was observed only in the L6 DRG. These findings suggested that c-jun and c-fos might be related to the acupuncture promoted spinal cord plasticity as reported previously. [Copyright &y& Elsevier]