74 research outputs found
Simulation and Analysis of the Buffer Function of Freeway Greening on Out-of-Control Vehicles
Freeway greening and traffic safety has aroused more and more attention. The purpose of this study is to investigate the role of flexible green planting in buffering out-of-control vehicles. The stopping distances of vehicle rushing into greening were tested at 8 group of initial speeds range from 5km/h to 40km/h in green belt, and a simplified mathematical model was built up to simulate the buffering process. The results indicated that the greening plants have certain buffering effect on vehicles and alleviate the crash damage within 30m of stopping distance for the vehicles under 40km/h, while the simplified mathematical model could reflect the buffering process of the plants actually by simulating the speed attenuation process, and it was found that the two types of resistance produced by the plants, i.e. counterforce of plants trunks and friction of branches and leaves, are the major factors during the vehicle deceleration.</p
Cosmic Radio Background from Primordial Black Holes at Cosmic Dawn
The presence of an extra radio background besides the cosmic microwave
background has important implications for the observation of the 21-cm signal
during the cosmic Dark Ages, Cosmic Dawn, and epoch of Reionization. The strong
absorption trough found in the 21-cm global spectrum measured by the EDGES
experiment, which has a much greater depth than the standard model prediction,
has drawn great interest to this scenario, but more generally it is still of
great interest to consider such a cosmic radio background (CRB) in the early
Universe. To be effective in affecting the 21-cm signal at early time, such a
radio background must be produced by sources which can emit strong radio
signals but modest amount of X-rays, so that the gas is not heated up too
early. We investigate the scenario that such a radio background is produced by
the primordial black holes (PBHs). For PBH with a single mass, we find that if
the PBHs' abundance (ratio of total PBH mass density to
total matter density) and mass satisfy the relation for , and have jet emission, they can generate
a CRB required for reproducing the 21-cm absorption signal seen by the EDGES.
The accretion rate can be boosted if the PBHs are surrounded by dark matter
halos, which permits lower value to satisfy the EDGES
observation. In the latter scenario, since the accretion rate can evolve
rapidly during the Cosmic Dawn, the frequency (redshift) and depth of the
absorption trough can determine the mass and abundance of the PBHs
simultaneously. For absorption trough redshift 17 and depth
mK, it corresponds to and .Comment: 16 pages, 13 figures, accepted for publication in PR
Differential Proteomics Identification of HSP90 as Potential Serum Biomarker in Hepatocellular Carcinoma by Two-dimensional Electrophoresis and Mass Spectrometry
The aim of the current study is to identify the potential biomarkers involved in Hepatocellular carcinoma (HCC) carcinogenesis. A comparative proteomics approach was utilized to identify the differentially expressed proteins in the serum of 10 HCC patients and 10 controls. A total of 12 significantly altered proteins were identified by mass spectrometry. Of the 12 proteins identified, HSP90 was one of the most significantly altered proteins and its over-expression in the serum of 20 HCC patients was confirmed using ELISA analysis. The observations suggest that HSP90 might be a potential biomarker for early diagnosis, prognosis, and monitoring in the therapy of HCC. This work demonstrates that a comprehensive strategy of proteomic identification combined with further validation should be adopted in the field of cancer biomarker discovery
Effect of ice water pretreatment on the quality of Pacific White Shrimps (Litopenaeus vannamei)
Pacific White Shrimps (Litopenaeus vannamei) are an aquaculture species with global importance. For the purpose of this paper, the quality shelling process of Pacific White Shrimps, freshly harvested from farms and stored in a mixture ice water up to 24 hr, was investigated. Both the differences and correlations between the indexes such as peeling time, shrimp yield, chromatic aberration, texture, K value, TBA value, and microstructure were compared and analyzed. The optimal shell peeling time of Pacific White Shrimps was determined by ice water treatment for 8 hr. The shell peeling time was 1.77 min, the elasticity of the shrimp was 0.51 mm, the hardness was 2,124.58 g, K value was 1.33%, and TBA value was 0.004 mg/100 g. Both the smell and color of the shelled shrimp were normal. This study aims to endorse the mechanical shelling of Pacific White Shrimps
Roles of TGF-beta 1 signaling in the development of osteoarthritis
Osteoarthritis (OA) is a degenerative joint
disorder characterized by the destruction of articular
cartilage, subchondral bone and other joint tissues.
Although multiple growth factors and cytokines have
been shown to be involved in articular cartilage
degeneration and subchondral bone destruction, which
eventually leads to OA, the molecular mechanisms
underlying the pathogenesis of OA are largely unknown.
The canonical transforming growth factor beta 1 (TGFβ1) signaling functions as one of the key factors in
cartilage and bone formation, remodeling, and
maintenance. However, the effects of TGF-β1 signaling
on the development of OA are unclear. Numerous
studies provide evidence that TGF-β1 is required for the
formation of articular cartilage at early stages of joint
development. In contrast, other investigations indicate
that TGF-β1 may, in fact, be a factor in joint destruction.
Therefore, we, in this review article, discuss the
“conflicting” roles of TGF-β1 signaling in the
development of OA
Agricultural Vehicle Automatic Navigation Positioning and Obstacle Avoidance Technology Based on ICP
The problem of closed branches and leaves in orchards can cause satellite navigation systems to experience star loss, leading to safety issues such as collisions and loss of control. To address this issue, this study develops a multi-mode navigation control system for satellite navigation and sensor tracking, aiming to achieve multi-mode intelligent path judgment and ensure the accuracy and safety of operations. This method utilizes point cloud iterative nearest point algorithm LiDAR technology to gain 3D information of the surrounding environment when satellite signals are unavailable. Through perception and analysis of the environment, real-time path planning and obstacle avoidance decision-making are achieved. At the same time, through micro-inertial navigation technology, accurate perception and control of the position and attitude of navigation equipment are achieved, thereby achieving precise control of the operation process. According to relevant experimental data, the experimental distance accuracy based on the vehicle mounted daytime environment dataset was 84.88%, and the duration accuracy was 97.63%. Accordingly, the proposed system is capable of accurately determining the current position and heading, as well as making path planning and obstacle avoidance decisions based on real-time environmental information. This ensures the accuracy and safety of operations. The research method exhibits higher stability and reliability in orchard operations, providing an effective solution for the accuracy and safety of orchard operations
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