305 research outputs found
Ground state solutions for diffusion system with superlinear nonlinearity
In this paper, we study the following diffusion system
\begin{equation*}
\begin{cases}
\partial_{t}u-\Delta_{x} u +b(t,x)\cdot \nabla_{x} u +V(x)u=g(t,x,v),\\
-\partial_{t}v-\Delta_{x} v -b(t,x)\cdot \nabla_{x} v +V(x)v=f(t,x,u)
\end{cases}
\end{equation*}
where , and . Under suitable assumptions on the nonlinearity, we establish the existence of ground state solutions by the generalized Nehari manifold method developed recently by Szulkin and Weth
A336C/A336T/T337C variations in HBV core gene and spontaneous hepatitis B e antigen loss in chronic hepatitis B patients
<p>Abstract</p> <p>Background</p> <p>A336C/A336T/T337C variations in HBV core gene were demonstrated to relate to the decreases in serum HBV DNA levels and HBV replication in chronic hepatitis B patients. Usually the drastic decrease in serum HBV DNA levels correlates with spontaneous HBeAg loss during the course of chronic HBV infection. The aim of the present study was to investigate whether there was correlation between A336C/A336T/T337C variations and spontaneous HBeAg loss</p> <p>Methodology/Principal Findings</p> <p>A modified PCR-RFLP assay and ELISA were adopted to determine A336C/A336T/T337C variations and serum HBeAg levels in chronic hepatitis B patients without any antiviral therapy, respectively, whereas G1896A variation and HBV genotype were detected using Taqman-PCR assay. RFLP pattern C, E, G, C/G mixture and a new pattern C' were found in this study. A336C/A336T/T337C variations occurred in 40/166(24.1%) chronic hepatitis B patients. Chi-square test showed that C336/T336/C337 variants was more frequent in chronic hepatitis B patients with A1896 variants than those with the wild type G1896 (χ2 = 4.7, P = 0.03), and moreover, patients with C336/T336/C337 variants had a significantly lower HBeAg-positive percentage than those with the wild type A336/T337. Binary logistic regression identified genotype B (OR = 4.1, 95%CI = 1.8-9.2, P = 0.001), the presence of C336/T336/C337 variants (OR = 3.2, 95%CI = 1.2-8.5, P = 0.02) and A1896 variants (OR = 7.8, 95%CI = 3.3-18.5, P < 0.001) as independent factors associated with spontaneous HBeAg loss.</p> <p>Conclusion/Significance</p> <p>A336C/A336T/T337C were naturally occurring polymorphisms in HBV core gene, and moreover, the presence of C336/T336/C337 variants was first demonstrated to be an independent factor associating with spontaneous HBeAg loss in chronic hepatitis B patients.</p
Research On Low Frequency Vibration Of Rotary Compressor
The abnormal noise of an outdoor domestic air-conditioner operating at low speed is experimentally analyzed. The structure-borne noise which passes through the mounting system is confirmed to be the main source of the abnormal noise due to the large low frequency vibration on compressor foot. Then the characteristic of low frequency vibration of rotary compressor including the dynamic model, exciting forces and dynamic response is researched. Based on this, mounting system including compressor foot and rubber grommet is optimized to solve this problem, more than 8dB reduced
Does the Enigmatic Wightia Belong to Paulowniaceae (Lamiales)?
The familial placement of Wightia has been controversial in the Lamiales, and the genus is currently placed in Paulowniaceae in APG IV. Phylogenetic analyses of Wightia and its close relatives in Lamiales are conducted using sequences of the complete chloroplast genomes as well as sequence data from nine chloroplast DNA regions (atpB, matK, ndhF, psbBTNH, rbcL, rps4, rps16 intron, trnL-F, and trnV-atpE) and one mitochondrial gene rps3. The maximum likelihood and Bayesian analyses do not support a close relationship between Wightia and Paulownia of Paulowniaceae; instead the enigmatic Wightia is sister to Phrymaceae with strong support in all analyses. Hence Wightia should not be placed in Paulowniaceae. Because morphological data show Wightia’s affinity to both Phrymaceae and Paulowniaceae and prior nrITS data suggest its sister relationship to Paulownia of Paulowniaceae, it is likely that Wightia may have had a hybrid origin between early lineages of Phrymaceae and Paulowniaceae. It is therefore the best to exclude Wightia from Paulowniaceae and place the genus as unassigned until further nuclear data to test the hybrid hypothesis. The seven species of Paulownia constitute a monophyletic group, and Paulowniaceae is supported to be a monogeneric family, consistent with a series of morphological and floral development characters. The genus Brandisia, which was sometimes regarded as a close relative of Wightia, is supported to be nested within Orobanchaceae, as sister to Pterygiella. This sister relationship can be corroborated by fruit, seed and pollen morphological characters
Stability analysis and output feedback control for stochastic networked systems with multiple communication delays and nonlinearities using fuzzy control technique
Ramsey interferometry through coherent coupling and population transfer in N air laser
The laser-like coherent emission at 391nm from N gas irradiated by strong
800nm pump laser and weak 400nm seed laser is theoretically investigated.
Recent experimental observations are well simulated, including temporal
profile, optical gain and periodic modulation of the 391nm signal from N.
Our calculation sheds light on the long standing controversy on whether
population inversion is indispensable for the optical gain. We demonstrate the
Ramsey interference fringes of the emission intensity at 391nm formed by
additionally injecting another 800nm pump or 400nm seed, which are well
explained by the coherent modulation of transition dipole moment and population
between the - states as well as the
- states. This study provides versatile
possibilities for the coherent control of air laser.Comment: 5 pages, 5 figure
- …