Bronchopulmonary dysplasia (BPD) is an important complication of mechanical ventilation in preterm infants, and no definite therapy can eliminate this complication. Pulmonary inflammation plays a ...crucial role in its pathogenesis, and glucocorticoid is one potential therapy to prevent BPD.
To compare the effect of intratracheal administration of surfactant/budesonide with that of surfactant alone on the incidence of death or BPD.
A clinical trial was conducted in three tertiary neonatal centers in the United States and Taiwan, in which 265 very-low-birth-weight infants with severe respiratory distress syndrome who required mechanical ventilation and inspired oxygen (fraction of inspired oxygen, ≥50%) within 4 hours of birth were randomly assigned to one of two groups (131 intervention and 134 control). The intervention infants received surfactant (100 mg/kg) and budesonide (0.25 mg/kg), and the control infants received surfactant only (100 mg/kg), until each infant required inspired O2 at less than 30% or was extubated.
The intervention group had a significantly lower incidence of BPD or death (55 of 131 42.0% vs. 89 of 134 66%; risk ratio, 0.58; 95% confidence interval, 0.44-0.77; P < 0.001; number needed to treat, 4.1; 95% confidence interval, 2.8-7.8). The intervention group required significantly fewer doses of surfactant than did the control group. The intervention group had significantly lower interleukin levels (IL-1, IL-6, IL-8) in tracheal aspirates at 12 hours and lower IL-8 at 3-5 and 7-8 days.
In very-low-birth-weight infants with severe respiratory distress syndrome, intratracheal administration of surfactant/budesonide compared with surfactant alone significantly decreased the incidence of BPD or death without immediate adverse effect. Clinical trial registered with www.clinicaltrials.gov (NCT-00883532).
ABSTRACT
WRKY‐type transcription factors are involved in multiple aspects of plant growth, development and stress response. WRKY genes have been found to be responsive to abiotic stresses; however, ...their roles in abiotic stress tolerance are largely unknown especially in crops. Here, we identified stress‐responsive WRKY genes from wheat (Triticum aestivum L.) and studied their functions in stress tolerance. Forty‐three putative TaWRKY genes were identified and two multiple stress‐induced genes, TaWRKY2 and TaWRKY19, were further characterized. TaWRKY2 and TaWRKY19 are nuclear proteins, and displayed specific binding to typical cis‐element W box. Transgenic Arabidopsis plants overexpressing TaWRKY2 exhibited salt and drought tolerance compared with controls. Overexpression of TaWRKY19 conferred tolerance to salt, drought and freezing stresses in transgenic plants. TaWRKY2 enhanced expressions of STZ and RD29B, and bound to their promoters. TaWRKY19 activated expressions of DREB2A, RD29A, RD29B and Cor6.6, and bound to DREB2A and Cor6.6 promoters. The two TaWRKY proteins may regulate the downstream genes through direct binding to the gene promoter or via indirect mechanism. Manipulation of TaWRKY2 and TaWRKY19 in wheat or other crops should improve their performance under various abiotic stress conditions.
WRKY‐type transcription factors are involved in multiple aspects of plant growth and development. Their roles in abiotic stress tolerance are largely unknown especially in crops. Here, we find that TaWRKY2 and TaWRKY19 from wheat play differential roles in abiotic stress tolerance through activation of different downstream genes.
Since Venus has no substantial planetary magnetic field, the fast‐flowing solar wind plasma interacts directly with its ionosphere, upper atmosphere, and corona. The thermal atmosphere and hot oxygen ...corona of Venus are expected to play essential roles in the interaction process. To quantify their effects, we combine three major state‐of‐the‐art three‐dimensional numerical models, including (a) The Venus thermosphere general circulation model (VTGCM), (b) The adaptive mesh particle simulator (AMPS), and (c) A multi‐species Magnetohydrodynamics (MHD) model of Venus based on Block Adaptive Tree Solar‐wind Roe Upwind Scheme. The global multi‐species MHD model is used to simulate the planet's interaction with the ambient solar wind, where the background neutral densities are provided by VTGCM and AMPS. Using the above‐mentioned numerical models, the effect of the upper atmosphere and corona on solar wind driven ion escape rates are examined for three typical solar cycle conditions, including solar maximum, solar median, and solar minimum conditions. The model results suggest that even though the hot oxygen corona only has a minor effect on the ion density profiles in the ionosphere, it can enhance ion loss rate up to ∼25% for high solar activity.
Key Points
An advanced magnetohydrodynamics model is used to quantify the effects of the neutral atmosphere of Venus on the solar wind interaction process
Realistic 3D neutral atmospheres change ion densities in the upper ionosphere and the ion loss rates for different solar activities
The hot oxygen corona significantly increases the total ion loss rate under solar maximum conditions
In this paper, the plastic model of ordinary state‐based peridynamics is established. The size and shape of plastic zone around crack tips with the different inclination angles are simulated using ...ordinary state‐based peridynamics. Comparison of the size and shape of plastic zone around the crack tips obtained from peridynamic solution and analytic solution is made. It is found that the relative errors between the analytical and peridynamic solution are very little. Therefore, it is feasible to predict the plastic zone around crack tips using ordinary state‐based peridynamics.
A compact laser plasma accelerator (CLAPA) that can stably produce and transport proton ions with different energies less than 10 MeV,<1%energy spread, several to tens of pC charge, is demonstrated. ...The high current proton beam with continuous energy spectrum and a large divergence angle is generated by using a high contrast laser and micron thickness targets, which later is collected, analyzed and refocused by an image-relaying beam line using a combination of quadrupole and bending electromagnets. It eliminates the inherent defects of the laser-driven beams, realizes precise manipulation of the proton beams with reliability, availability, maintainability and inspectability (RAMI), and takes the first step towards applications of this new generation of accelerator. With the development of high-rep rate Petawatt (PW) laser technology, we can now envision a new generation of accelerator for many applications in the near future soon.
A deflection effect of an intense laser beam with spin angular momentum is revealed theoretically by an analytical modeling using radiation pressure and momentum balance of laser plasma interaction ...in the relativistic regime as a deviation from the law of reflection. The reflected beam deflects out of the plane of incidence with a deflection angle up to several milliradians, when a nonlinear polarized laser, with the intensity I_{0}∼10^{19}W/cm^{2} and duration around tens of femtoseconds, is obliquely incident and reflected by an overdense plasma target. This effect originates from the asymmetric radiation pressure caused by spin angular momentum of the laser photons. The dependence of the deflection angle of a Gaussian-type laser on the parameters of laser pulse and plasma foil is theoretically derived, which is also confirmed by three-dimensional particle-in-cell simulations of circularly polarized laser beams with the different intensity and pulse duration.
In order to implement radiotherapy based on a laser accelerator, it is necessary to precisely control the spatial distribution and energy spectrum of the proton beams to meet the requirements of the ...radiation dose distribution in the three-dimensional biological target. A compact laser plasma accelerator has been built at Peking University, which can reliably generate and transport MeV-energy protons with a specified energy onto the irradiation platform. In this paper, we discuss several technologies for the accurate control of a laser-accelerated proton beam with large divergence angle and broad energy spread, including the determination of the beam source position with micron accuracy, a tuning algorithm for the transport line which we refer to as “matching-image-point two-dimensional energy analysis” to realize accurate energy selection, and the control of beam distribution uniformity. In the prototype experiment with low energy protons and 0.5-Hz irradiation rate, a tailored energy deposition is demonstrated, which shows the potential feasibility of future irradiation based on laser-accelerated proton beams.
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