1,785 research outputs found
The introduction of the new control method of plant viruses infection for organic farming
Pepper mild mosaic virus (PMMoV) and cucumber mosaic virus (CMV) are economically important viruses, which cause enormous losses by infecting various vegetable crops. worldwide. Various strategies based on the avoidance of sources of infection, control of vectors have been conventionally employed to minimize the losses caused by these viruses. These strategies, however have not been effective as control tools. We have found that the extracts of gallnuts from Quercus dentate and Rhus javanica strongly inhibit PMMoV and CMV infection. The gallnuts are plant excretion produced when irritants are released by the larvae of gall insects. They contain high amounts of tannic acid such as gallic acid and ellagic acid. Also the gallnut extracts are widely used in pharmaceuticals, food and feed additives, it is safe natural material which can be used in organic farming. Our results indicate that they are potent plant viruses inhibitors that maybe used to prevent the spread of viruses infections in the cultivating farm
Anisotropic optical response of nanocrystalline v2O5 thin films and effects of oxygen vacancy formation
We report a high sensitivity to oxygen vacancy formation as well as the temperature dependence of anisotropic optical properties of a nanocrystalline V2O5 thin film. Spectroscopic ellipsometry data show that the film has a uniaxial optical anisotropy due to a highly ordered nanocrystalline layer structure. The anisotropic optical properties of the film begin to change at 400 K in a high vacuum and can be linked to the changes in the electronic structure of the film upon reduction. An increase in the refractive indices, anisotropic changes of the optical conductivities, and a decrease in film thickness are observed after vacuum heating and are recovered to original values by heating in air up to 480 K. The experimental results are supported by the previous theoretical studies on the stability of reduced V2O5 surface through the formation of oxygen vacancies. We discuss the formation of oxygen vacancies, vacancy-induced structural relaxations, and changes in the electronic structure of V2O5 in conjunction with the experimental results.1441sciescopu
Development of wirelessly-powered, extracranial brain activator (ECBA) in a large animal model for the future non-invasive human neuromodulation
As transcranial electrical stimulation (tES) is an emerging and promising technique for neuromodulation, we developed a novel device; wirelessly-powered, extracranial brain activator (ECBA), which is mounted subcutaneously, and its neuromodulation effect was investigated. The oscillatory changes in electrocorticography (EcoG) were analyzed from two types of stimulation. Two weeks prior to the recording experiment, we underwent surgery for implantation of subdural strips and ECBA module over centroparietal regions of anesthetized beagles. Low-frequency stimulation (LFS) and subsequent high-frequency stimulation (HFS) protocols (600 pulses respectively) were applied. Then, the power changes before and after each stimulation in five different bands were compared. A significantly larger voltage difference with subcutaneous than transcutaneous stimulation measured at EcoG channels indicated a substantial current attenuation between the skin and skull. Compared with the baseline, all subjects showed consistently decreased delta power and increased gamma power after HFS. LFS also induced a similar, but opposite, pattern of power change in four beagles. The results from this study indicate that LFS and HFS with our novel ECBA can consistently and effectively modulate neural activity of the cortex, inducing neural inhibition and facilitation functions, respectively. Future studies are necessary to further ensuring a consistent efficacy and long-term safety.11Ysciescopu
QCD Chiral restoration at finite under the Magnetic field: Studies based on the instanton vacuum model
We investigate the chiral restoration at finite temperature under the
strong external magnetic field of the SU(2) light-flavor
QCD matter. We employ the instanton-liquid QCD vacuum configuration accompanied
with the linear Schwinger method for inducing the magnetic field. The
Harrington-Shepard caloron solution is used to modify the instanton parameters,
i.e. the average instanton size and inter-instanton distance
, as functions of . In addition, we include the meson-loop
corrections (MLC) as the large- corrections because they are critical
for reproducing the universal chiral restoration pattern. We present the
numerical results for the constituent-quark mass as well as chiral condensate
which signal the spontaneous breakdown of chiral-symmetry (SBS), as
functions of and . Besides we find that the changes for the and
due to the magnetic field is relatively small, in comparison to those
caused by the finite effect.Comment: 4 pages, 1 table, 6figs. arXiv admin note: significant text overlap
with arXiv:1103.605
Insulin aggregation tracked by its intrinsic TRES
Time-resolved emission spectra (TRES) have been used to detect conformational changes of
intrinsic tyrosines within bovine insulin at a physiological pH. The approach offers the ability to
detect the initial stages of insulin aggregation at the molecular level. The data analysis has revealed
the existence of at least three fluorescent species undergoing dielectric relaxation and significant
spectral changes due to insulin aggregation. The results indicate the suitability of the intrinsic
TRES approach for insulin studies and for monitoring its stability during storage and aggregation
in insulin delivery devices
Generating uniform random vectors in \QTR{bf}{Z}_{p}^{k}: the general case
This paper is about the rate of convergence of the Markov chain
(mod ), where is an integer matrix with nonzero
eigenvalues and is a sequence of independent and identically
distributed integer vectors, with support not parallel to a proper subspace of
invariant under . If for all eigenvalues
of , then steps are sufficient and
steps are necessary to have sampling from a nearly uniform
distribution. Conversely, if has the eigenvalues that are
roots of positive integer numbers, and for
all , then steps are necessary and sufficient.Comment: The published version is to appear in the Journal of Theoretical
Probabilit
Dynamic assembly of Hda and the sliding clamp in the regulation of replication licensing
Regulatory inactivation of DnaA (RIDA) is one of the major regulatory mechanisms of prokaryotic replication licensing. In RIDA, the Hda-sliding clamp complex loaded onto DNA directly interacts with adenosine triphosphate (ATP)-bound DnaA and stimulates the hydrolysis of ATP to inactivate DnaA. A prediction is that the activity of Hda is tightly controlled to ensure that replication initiation occurs only once per cell cycle. Here, we determined the crystal structure of the Hda-�� clamp complex. This complex contains two pairs of Hda dimers sandwiched between two �� clamp rings to form an octamer that is stabilized by three discrete interfaces. Two separate surfaces of Hda make contact with the �� clamp, which is essential for Hda function in RIDA. The third interface between Hda monomers occludes the active site arginine finger, blocking its access to DnaA. Taken together, our structural and mutational analyses of the Hda-�� clamp complex indicate that the interaction of the �� clamp with Hda controls the ability of Hda to interact with DnaA. In the octameric Hda-�� clamp complex, the inability of Hda to interact with DnaA is a novel mechanism that may regulate Hda function. ? The Author(s) 2017.113Ysciescopu
Finite Size and Current Effects on IV Characteristics of Josephson Junction Arrays
The effects of finite size and of finite current on the current-voltage
characteristics of Josephson junction arrays is studied both theoretically and
by numerical simulations. The cross-over from non-linear to linear behavior at
low temperature is shown to be a finite size effect and the non-linear behavior
at higher temperature, , is shown to be a finite current effect.
These are argued to result from competition between the three length scales
characterizing the system. The importance of boundary effects is discussed and
it is shown that these may dominate the behavior in small arrays.Comment: 5 pages, figures included, to appear in PR
Chiral Symmetry and Diffractive Neutral Pion Photo- and Electroproduction
We show that diffractive production of a single neutral pion in
photon-induced reactions at high energy is dynamically suppressed due to the
approximate chiral symmetry of QCD. These reactions have been proposed as a
test of the odderon exchange mechanism. We show that the odderon contribution
to the amplitude for such reactions vanishes exactly in the chiral limit. This
result is obtained in a nonperturbative framework and by using PCAC relations
between the amplitudes for neutral pion and axial vector current production.Comment: 22 pages, 7 figure
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