2,982 research outputs found
First-Principles Calculation of Principal Hugoniot and K-Shell X-ray Absorption Spectra for Warm Dense KCl
Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are
calculated using the first-principles molecular dynamics method. Evolution of
electronic structures as well as the influence of the approximate description
of ionization on pressure (caused by the underestimation of the energy gap
between conduction bands and valence bands) in the first-principles method are
illustrated by the calculation. Pressure ionization and thermal smearing are
shown as the major factors to prevent the deviation of pressure from global
accumulation along the Hugoniot. In addition, cancellation between electronic
kinetic pressure and virial pressure further reduces the deviation. The
calculation of X-ray absorption spectra shows that the band gap of KCl persists
after the pressure ionization of the electrons of Cl and K taking place at
lower energy, which provides a detailed understanding to the evolution of
electronic structures of warm dense matter
Detection and identification of Staphylococcus aureus in raw milk by hybridization to oligonucleotide microarray
Staphylococcus aureus causes foodborne diseases if consumed in contaminated milk products. Rapid detection and characterization of foodborne pathogen S. aureus is crucial for epidemiological investigations and food safety surveillance. It is still a challenge to detect and identify bacterial pathogens quickly and accurately according to the samples. In this study, we have amplified 16S rRNA of S. aureus by specific primers, designed oligonucleotide probes, detected the sensitivity and specificity of the microarray assay, and also identified S. aureus in the raw milk samples by hybridization. The S. aureus and 2 control pathogens (Streptococcus suis in pigs and Shigella) were used for specificity of the microarray assay. Based upon the hybridization results, universal probes for bacterial pathogens, S. aureus probe, Staphylococcus spp. probe, nucleic acid fixture positive controls and positive experimental control showed positive signals with targeted S. aureus. The samples werediluted from 101 to 106 cfu per ml for evaluating the sensitivity of the microarray assay. The levels were as high as 103 cfu per ml, all of the samples showed positive signals. This method for rapid and effectivedetection and identification of S. aureus in raw milk demonstrated high sensitivity and specificity
Gradient Ultra-fine Grained Surface Layer in 6063 Aluminum Alloy Obtained by Means of Rotational Accelerated Shot Peening
Gradient ultra-fine grained surface layer in 6063 aluminum alloy was obtained by means of a novel surface self-nanocrystallization technique, namely rotational accelerated shot peening (RASP) treatment. The average grain sizes along the vertical section vary from hundreds of nanometers in the top surface to micrometers in the matrix. By using orthogonal experimental design to compare roughness values and hardness values, we synthesized the processing parameters to obtain sample of smaller roughness values and higher hardness
Dynamic response and dangerous point stress analysis of gear transmission system
Gear transmission is the principal power transmission mode of many machine, the reliability of transmission system has important influence on the accomplishment of daily task. This paper made a gear transmission system as the research object, we build the two-stage gear transmission system model and calculate its dynamic response in theory. Then, we study the mesh stiffness of gear concerning the variation of the mesh position from the gear transmission system. On the basis of these work, we establish the gear system’s finite element simulation model considering the tooth contact of internal gear system. After the simulation, we had get the contact response and the time history of some important area’s equivalent stress. Through these work, we can study the contact stress of the two-stage gear system in theory method and finite element simulation method, which has a guiding significance on the optimum structural design of two-stage transmission gear system
Shadow Thermodynamics of AdS Black Hole with the Nonlinear Electrodynamics Term
In this paper, we have creatively employed the shadow radius to study the
thermodynamics of a charged AdS black hole with a nonlinear
electrodynamics(NLED) term. First, the connection between the shadow radius and
event horizon is constructed with the aid of the geodesic analysis. It turns
out that the black hole shadow radius shows a positive correlation as a
function of the event horizon radius. Then in the shadow context, we found that
the black hole temperature and heat capacity can be presented by the shadow
radius. And further analysis shows that the shadow radius can do as well as the
event horizon in revealing black hole phase transition process. In this sense,
we constructed the thermal profile of the charged AdS black hole with inclusion
of the NLED effect. In P < Pc case, it is found that the N-type trend of the
temperature given by the shadow radius is always coincide with that obtained by
using the event horizon. So, we can concluded for the charged AdS black hole
that the phase transition process can be intuitively presented as the thermal
profile in the shadow context. Finally, the effects of NLED have been carefully
analysed through out the paper.Comment: 17 pages, 21 figure
Spindle oscillations are generated in the dorsal thalamus and modulated by the thalamic reticular nucleus
Spindle waves occur during the early stage of slow wave sleep and are thought to arise in the thalamic reticular nucleus (TRN), causing inhibitory postsynaptic potential spindle-like oscillations in the dorsal thalamus that are propagated to the cortex. We have found that thalamocortical neurons exhibit membrane oscillations that have spindle frequencies, consist of excitatory postsynaptic potentials, and co-occur with electroencephalographic spindles. TRN lesioning prolonged oscillations in the medial geniculate body (MGB) and auditory cortex (AC). Injection of GABA~A~ antagonist into the MGB decreased oscillation frequency, while injection of GABA~B~ antagonist increased spindle oscillations in the MGB and cortex. Thus, spindles originate in the dorsal thalamus and TRN inhibitory inputs modulate this process, with fast inhibition facilitating the internal frequency and slow inhibition limiting spindle occurrence
Startle response related genes
The startle reaction (also known as the startle response, the startle reflex, or the alarm reaction) is the psychological and physiological response to a sudden unexpected stimulus, such as a flash of light, a loud noise (acoustic startle reflex), or a quick movement near the face. Abnormalities of startle response have been observed in many stress-related mental disorders, such as schizophrenia and post-traumatic stress disorder (PTSD). However, the molecular mechanisms of startle in stress-associated conditions – for example, whether the startle reaction is associated with any gene variance – is still unknown. In this paper, we will carry out a systematic review by retrieving, assessing, and combining, when applicable, individual studies investigating association of the molecular variation of candidate gene with the startle response. The systematic review is based on the search for numerous publications using the keywords ‘‘startle gene’’ on September 15, 2010 using PubMed, which comprises more than 20 million citations for biomedical literature from MEDLINE and life science journals. A total of 486 publications regarding genes associated with startle have been obtained and reviewed here. There are fewer than 20 publications associating genes with the startle response between 1979, when the first valuable paper was published, and 1999. However, publications have dramatically increase from 2001 and reaches over 70 in 2009. We have characterized them into three categories: startle-associated gene studies in humans, in animals, as well as in both human and animals. This review of research strategy may provide the information for identifying a biomarker for startle response, with the objective of translating research into clinical utility: diagnosis and treatment of stress-induced mental disorders
Startle response related genes
The startle reaction (also known as the startle response, the startle reflex, or the alarm reaction) is the psychological and physiological response to a sudden unexpected stimulus, such as a flash of light, a loud noise (acoustic startle reflex), or a quick movement near the face. Abnormalities of startle response have been observed in many stress-related mental disorders, such as schizophrenia and post-traumatic stress disorder (PTSD). However, the molecular mechanisms of startle in stress-associated conditions – for example, whether the startle reaction is associated with any gene variance – is still unknown. In this paper, we will carry out a systematic review by retrieving, assessing, and combining, when applicable, individual studies investigating association of the molecular variation of candidate gene with the startle response. The systematic review is based on the search for numerous publications using the keywords ‘‘startle gene’’ on September 15, 2010 using PubMed, which comprises more than 20 million citations for biomedical literature from MEDLINE and life science journals. A total of 486 publications regarding genes associated with startle have been obtained and reviewed here. There are fewer than 20 publications associating genes with the startle response between 1979, when the first valuable paper was published, and 1999. However, publications have dramatically increase from 2001 and reaches over 70 in 2009. We have characterized them into three categories: startle-associated gene studies in humans, in animals, as well as in both human and animals. This review of research strategy may provide the information for identifying a biomarker for startle response, with the objective of translating research into clinical utility: diagnosis and treatment of stress-induced mental disorders
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