2,304 research outputs found
Asia-Pacific Trade and Investment Review
This book reviews latest trends in trade and investment policy issues facing Asia-Pacific region.Trade, Foreign Direct Investment, Financial Crisis, Environment, Agricultural Trade Liberalization, WTO
A study of GPS and other navigation systems for high precision navigation and attitude determination
Analysis of changes in ecosystem capacity index and driving factors in the Loess Plateau under ecological engineering orientation
BackgroundIn recent decades, the Loess Plateau is one of the regions in China that urgently needs ecological governance due to the severe situation of soil erosion and land desertification. Due to the impact of climate change and human activities, the threat to the ecological space security of the Loess Plateau has intensified. This paper reveals the time lag effect of ecological engineering construction on the changes in the ecosystem service capacity index of the Loess Plateau, providing a scientific basis and decision-making reference for the sustainable development of the study area and improving the quality and management of ecological engineering construction, which is of great significance for building a solid ecological security barrier on the Loess Plateau.MethodsBased on the hierarchical analysis method, quantitative indicator method, spatial correlation analysis method and two-way fixed effect model, this paper analyzes the temporal and spatial changes of the ecosystem service capacity index of the Loess Plateau under the background of ecological engineering implementation.ResultsThe results showed that: 1) the vegetation coverage of the Loess Plateau increased with the increase of the area of ecological engineering construction, and showed a fluctuating growth distribution characteristic from southeast to northwest in space; 2) the water conservation capacity index, wind and sand fixation capacity index, biodiversity capacity index and comprehensive service capacity index of the Loess Plateau from 2000 to 2020 all showed exponential growth, which were highly coupled with the growth and change of vegetation coverage area in time and space; 3) the cold spots and hot spots of the ecosystem service capacity index of the Loess Plateau showed a step-by-step decrease of "hot in the south and cold in the north" in spatial distribution; the hot spots and sub-hot spots showed a reciprocating cycle from aggregation to fragmentation in time and space; the cold spots and sub-cold spots were mainly distributed in the northwest region. 4) The changes in the ecosystem service capacity index of the Loess Plateau were mainly affected by factors such as the cumulative project implementation area, urbanization rate and precipitation.ConclusionThe construction of ecological engineering on the Loess Plateau has achieved remarkable results. The growth of vegetation coverage area and ecosystem service capacity index on the Loess Plateau from 2000 to 2020 has promoted the recovery of ecosystem functions. Therefore, we should actively promote the construction of ecological projects to provide scientific decision-making references for solving regional ecological security issues
Recent advancement in stem cell treatment of coronary artery lesion of kawasaki disease
Kawasaki Disease (KD) is an acute, self-limited systemic vasculitis that affects the middle and small arteries, especially the coronary arteries. The incidence of KD is currently on the rise, with about 15 to 25 percent of children without systemic treatment, eventually developing coronary artery damage, Becoming the most common cause of child-acquired heart disease in the developed countries. At present, stem cell therapy for Kawasaki Disease in mice model has made important progress. This article reviews stem cell treatment of coronary artery lesion of Kawasaki Disease
Research on the Joint Construction of a National Multi-source and Multi-resolution image Checkpoint Database
In the process of quality inspection of Remote sensing image data results, the reuse of spatial location information of multiple units, multiple projects and multiple sources can not only overcome the problems of long time to obtain control information, high cost and difficulty in obtaining some areas, but also the basis for achieving efficient and high-precision geometric correction. From the perspective of reusability of checkpoints and saving the cost of quality inspection of remote sensing images, this paper discusses the necessity of joint construction of multi-source and multi-resolution image checkpoint database. And put forward the construction principle and management objectives of checkpoint database. At last, this paper briefly introduces and prospects the application of the national multi-source and multi-resolution image checkpoint database
Effects of Coptis extract combined with chemotherapeutic agents on ROS production, multidrug resistance, and cell growth in A549 human lung cancer cells
Background: Non–small cell lung cancer is associated with high expression of multidrug resistance (MDR) proteins and low production of reactive oxygen species (ROS). Coptis extract (COP), a Chinese medicinal herb, and its major constituent, berberine (BER), have anticancer properties. This study aims to investigate the effects of COP and BER combined with chemotherapeutic agents, including fluorouracil (5-FU), camptothecin (CPT), and paclitaxel (TAX), on cell proliferation, ROS production, and MDR in A549 human non-small cell lung cancer cells. Methods: A549 cells were treated with different doses of COP and BER, combined with 5-FU, CPT, and TAX. Cell viability was measured by an XTT (2,3-bis-(2-methoxy-4- nitro-5-sulfophenyl)-2 H-tetrazolium-5-carboxanilide) assay. Intracellular ROS levels were determined by measuring the oxidative conversion of cell permeable 2′,7′-dichlorofluorescein diacetate to fluorescent dichlorofluorescein. MDR of A549 cells was assessed by rhodamine 123 retention assay. Results: Both COP and BER significantly inhibited A549 cell growth in a dose-dependent manner. Combinations of COP or BER with chemotherapeutic agents (5-FU, CPT, and TAX) exhibited a stronger inhibitory effect on A549 cell growth. In addition, COP and BER increased ROS production and reduced MDR in A549 cells. Conclusion: As potential adjuvants to chemotherapy for non–small cell lung cancer, COP and BER increase ROS production, reduce MDR, and enhance the inhibitory effects of chemotherapeutic agents on A549 cell growth
Criticality-Based Quantum Metrology in the Presence of Decoherence
Quantum metrology aims to use quantum resources to improve the precision of
measurement. Quantum criticality has been presented as a novel and efficient
resource. Generally, protocols of criticality-based quantum metrology often
work without decoherence. In this paper, we address the issue whether the
divergent feature of the inverted variance is indeed realizable in the presence
of noise when approaching the QPT. Taking the quantum Rabi model (QRM) as an
example, we obtain the analytical result for the inverted variance. We show
that the inverted variance may be convergent in time due to the noise. When
approaching the critical point, the maximum inverted variance demonstrates a
power-law increase with the exponent -1.2, of which the absolute value is
smaller than that for the noise-free case, i.e., 2. We also observe a power-law
dependence of the maximum inverted variance on the relaxation rate and the
temperature. Since the precision of the metrology is very sensitive to the
noise, as a remedy, we propose performing the squeezing operation on the
initial state to improve the precision under decoherence. In addition, we also
investigate the criticality-based metrology under the influence of the
two-photon relaxation. Contrary to the single-photon relaxation, the quantum
dynamics of the inverted variance shows a completely-different behavior. It
does not oscillate with the same frequency with respect to the re-scaled time
for different dimensionless coupling strengths. Strikingly, although the
maximum inverted variance still manifests a power-law dependence on the energy
gap, the exponent is positive and depends on the dimensionless coupling
strength. This observation implies that the criticality may not enhance but
weaken the precision in the presence of two-photon relaxation. It can be well
described by the non-linearity introduced by the two-photon relaxation.Comment: 6 pages, 5 figure
HeadArtist: Text-conditioned 3D Head Generation with Self Score Distillation
This work presents HeadArtist for 3D head generation from text descriptions.
With a landmark-guided ControlNet serving as the generative prior, we come up
with an efficient pipeline that optimizes a parameterized 3D head model under
the supervision of the prior distillation itself. We call such a process self
score distillation (SSD). In detail, given a sampled camera pose, we first
render an image and its corresponding landmarks from the head model, and add
some particular level of noise onto the image. The noisy image, landmarks, and
text condition are then fed into the frozen ControlNet twice for noise
prediction. Two different classifier-free guidance (CFG) weights are applied
during these two predictions, and the prediction difference offers a direction
on how the rendered image can better match the text of interest. Experimental
results suggest that our approach delivers high-quality 3D head sculptures with
adequate geometry and photorealistic appearance, significantly outperforming
state-ofthe-art methods. We also show that the same pipeline well supports
editing the generated heads, including both geometry deformation and appearance
change.Comment: Amazing results are shown in
https://kumapowerliu.github.io/HeadArtist. Accepted by SIGGRAPH 202
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