ELONGATED HYPOCOTYL 5a modulates FLOWERING LOCUS T2 and gibberellin levels to control dormancy and bud break in poplar.

Photoperiod is a crucial environmental cue for phenological responses, including growth cessation and winter dormancy in perennial woody plants. Two regulatory modules within the photoperiod pathway explain bud dormancy induction in poplar (Populus spp.): the circadian oscillator LATE ELONGATED HYPOCOTYL 2 (LHY2) and GIGANTEA-like genes (GIs) both regulate the key target for winter dormancy induction FLOWERING LOCUS T2 (FT2). However, modification of LHY2 and GIs cannot completely prevent growth cessation and bud set under short-day (SD) conditions, indicating that additional regulatory modules are likely involved. We identified PtoHY5a, an orthologs of the photomorphogenesis regulatory factor ELONGATED HYPOCOTYL 5 (HY5) in poplar (Populus tomentosa), that directly activates PtoFT2 expression and represses the circadian oscillation of LHY2, indirectly activating PtoFT2 expression. Thus, PtoHY5a suppresses SD-induced growth cessation and bud set. Accordingly, PtoHY5a knockout facilitates dormancy induction. PtoHY5a also inhibits bud-break in poplar by controlling gibberellic acid (GA) levels in apical buds. Additionally, PtoHY5a regulates the photoperiodic control of seasonal growth downstream of phytochrome PHYB2. Thus, PtoHY5a modulates seasonal growth in poplar by regulating the PtoPHYB2-PtoHY5a-PtoFT2 module to determine the onset of winter dormancy, and by fine-tuning GA levels to control bud-break.

A Fast Intrusion Detection Method for High-Speed Railway Clearance Based on Low-Cost Embedded GPUs.

The efficiency and the effectiveness of railway intrusion detection are crucial to the safety of railway transportation. Most current methods of railway intrusion detection or obstacle detection are inappropriate for large-scale applications due to their high cost or limited coverage. In this study, we present a fast and low-cost solution to intrusion detection of high-speed railways. As the solution to heavy computational burdens in the current convolutional-neural-network-based detection methods, the proposed method is mainly a novel neural network based on the SSD framework, which includes a feature extractor using an improved MobileNet and a lightweight and efficient feature fusion module. In addition, aiming to improve the detection accuracy of small objects, the feature map weights are introduced through convolution operation to fuse features at different scales. TensorRT is employed to optimize and deploy the proposed network in the low-cost embedded GPU platform, NVIDIA Jetson TX2, to enhance the efficiency. The experimental results show that the proposed methods achieved 89% mAP on the railway intrusion detection dataset, and the average processing time for a single frame was 38.6 ms on the Jetson TX2 module, which satisfies the need of real-time processing.

Role of Na-Montmorillonite on Microbially Induced Calcium Carbonate Precipitation.

The use of additives has generated significant attention due to their extensive application in the microbially induced calcium carbonate precipitation (MICP) process. This study aims to discuss the effects of Na-montmorillonite (Na-MMT) on CaCO3 crystallization and sandy soil consolidation through the MICP process. Compared with the traditional MICP method, a larger amount of CaCO3 precipitate was obtained. Moreover, the reaction of Ca2+ ions was accelerated, and bacteria were absorbed by a small amount of Na-MMT. Meanwhile, an increase in the total cementing solution (TCS) was not conducive to the previous reaction. This problem was solved by conducting the reaction with Na-MMT. The polymorphs and morphologies of the CaCO3 precipitates were tested by using X-ray diffraction and scanning electron microscopy. Further, when Na-MMT was used, the morphology of CaCO3 changed from an individual precipitate to agglomerations of the precipitate. Compared to the experiments without Na-MMT in the MICP process, the addition of Na-MMT significantly reduced the hydraulic conductivity (HC) of sandy soil consolidated.

Comparison of an Emulsion- and Solution-Prepared Acrylamide/AMPS Copolymer for a Fluid Loss Agent in Drilling Fluid.

Acrylamide polymers were widely used as oilfield chemical treatment agents because of their wide viscosity range and versatile functions. However, with the increased formation complexity, their shortcomings such as poor solubility and low resistance to temperature, salt, and calcium were gradually exposed. In this paper, acrylamide (AM)/2-acrylamide-2-methyl-1-propane sulfonic acid (AMPS) copolymers were synthesized by aqueous solution polymerization and inverse emulsion polymerization, respectively. The aqueous polymer (W-AM/AMPS) and the inverse emulsion polymer (E-AM/AMPS) were characterized by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (1H NMR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and particle size analysis. The rheological properties, filtration properties, and sodium ion (Na+) and calcium ion (Ca2+) resistance were investigated. The results showed that E-AM/AMPS not only had a dissolution speed 4 times faster than that of W-AM/AMPS but also had superior shear-thinning performance both before and after aging. The filtration property of the bentonite system containing 2 wt % E-AM/AMPS was also better than that of the bentonite system containing 2 wt % W-AM/AMPS. In addition, E-AM/AMPS also exhibited extremely high tolerance for Na+ and Ca2+. The huge difference between rheological and filtration properties of E-AM/AMPS and W-AM/AMPS in drilling fluid can be attributed to the differences in the polymer microstructure caused by the two polymerization methods. Both FTIR and 1H NMR results showed that more hydrogen bonds were formed between E-AM/AMPS molecular groups and molecular chains, which led to a cross-linked network structure of E-AM/AMPS which was observed by TEM. It was this cross-linked network structure that made E-AM/AMPS have a high viscosity and allowed it to be better adsorbed on bentonite particles, thus exhibiting excellent rheological and filtration behavior. In addition, E-AM/AMPS powder had a high specific surface area so that it can be dissolved in water faster, greatly reducing the time and difficulty of configuring drilling fluid.

Synthesis of a Biodegradable and Environmentally Friendly Shale Inhibitor Based on Chitosan-Grafted l-Arginine for Wellbore Stability and the Mechanism Study.

We synthesized a biodegradable and environmentally friendly shale inhibitor based on chitosan-grafted l-arginine (CA) for wellbore stability in shale formation. The structure of CA was characterized by Fourier-transform infrared spectroscopy. Linear swelling, shale hot-rolling recovery, shale inhibition durability, and sedimentation experiments were used to evaluate the inhibition properties of CA and compared with the commonly used inhibitors potassium chloride (KCl) and polyamines (HPA and SIAT). The results showed that the inhibition of CA was better than that of KCl, HPA, and SIAT and that it can have a shale hot-rolling recovery of more than 90% at 150 °C, which indicated that CA had higher temperature resistance and longer durability. More importantly, it can be biodegraded as exhibited by the biodegradibility experiment. The inhibition mechanism of CA was studied by particle size distribution, X-ray diffraction, scanning electron microscopy, zeta potential analysis, and contact angle test. The strong inhibition of CA can be attributed to its encapsulation of MMT and shale surfaces. The CA with strongly positively charge was firmly adsorbed on the surface of MMT and shale, which not only neutralized the negative charge of MMT, compressed the diffused electric double layer, but also increased the contact angle of MMT and shale surface which enhancing hydrophobicity of MMT and shale. The hydration swelling and dispersion of MMT and shale were further inhibited. In addition, compatibility experiments showed that CA was compatible with commonly used treatment agents. CA did not affect the rheology of water-based drilling fluids and can reduce fluid loss after aging.

Micro-manganese as a weight agent for improving the suspension capability of drilling fluid and the study of its mechanism.

The contradiction between the sag stability of weighted materials and the rheological properties of drilling fluids is one of the main technical difficulties in high-density drilling fluids. Thus, understanding the suspension mechanism of weighting materials is the key to improving the sag stability of weighting materials. In this study, micro-manganese (Mn3O4) was compared with the commonly used weighting agent barite to study the suspension mechanism of Mn3O4. The weighting effect of Mn3O4 and barite was evaluated by static and dynamic sag tests, rheological property measurements and filtration property tests. The evaluation experiment results showed that the sag stability of Mn3O4 was better than that of barite, and Mn3O4 could significantly increase the suspension capacity of drilling fluids and improve their rheology property. The scanning electron microscopy (SEM) and other test results indicate that the small and uniform spherical structure of micro-manganese not only causes it to have less friction, but also intense Brownian motion in drilling fluid, which weakens the sag caused by gravity. The large specific surface area of Mn3O4 results in the strong adsorption of water molecules and polymers in drilling fluids, resulting in the formation of a hydrated film on the surface of the Mn3O4 particles and physical crosslinking with polymer chains. This prevents sagging caused by the adsorption of small particles to form large particles. The key findings of this work are expected to provide a basis for improving the sag stability of weighting materials in drilling fluids and better the application of micro-manganese in drilling fluids.

[Mechanism of heat shock protein 90 for regulating 26S proteasome in hyperthermia].

OBJECTIVE: To investigate the mechanism by which heat shock protein 90 (HSP90) regulates 26S proteasome in hyperthermia. METHODS: Hyperthermic HepG2 cell models established by exposure of the cells to 42 degrees celsius; for 3, 6, 12, and 24 h were examined for production of reactive oxygen species (ROS) and cell proliferation, and the changes in Hsp90α and 26S proteasome were analyzed. RESULTS: ROS production in the cells increased significantly after hyperthermia (F=28.958, P<0.001), and the cell proliferation was suppressed progressively as the heat exposure time extended (F=621.704, P<0.001). Hyperthermia up-regulated Hsp90α but decreased the expression level (F=164.174, P<0.001) and activity (F=133.043, P<0.001) of 26S proteasome. The cells transfected with a small interfering RNA targeting Hsp90α also showed significantly decreased expression of 26S proteasome (F=180.231, P<0.001). CONCLUSION: The intracellular ROS production increases as the hyperthermia time extends. Heat stress and ROS together cause protein denature, leading to increased HSP90 consumption and further to HSP90 deficiency for maintaining 26S proteasome assembly and stability. The accumulation of denatured protein causes unfolded protein reaction in the cells to eventually result in cell death.

[Synthesis and Characterization of PAM Derivative Weak Gel].

Weak gel with PAM cross-linked radical reaction was prepared by being incorporated to side chain of PAM. The structure, gel for ming process and the influence of NaCl concentration to apparent viscosity of gel were studied. The results show that the crosslinking ratios influence to crosslinking time, gel breaking time and gel strength. The crosslinking time decreases and gel strength slightly increases with increase of crosslinking ratio. Apparent viscosity of Polyacrylamide derivative crosslinking system increases with increase of NaCl concentration. The weak gel has good salt tolerance ability.

[Score in APACHEâ ¡derived from critical clinic information system is more accurate than artificial method].

OBJECTIVE: To evaluate the accuracy of APACHEⅡ score derived from critical clinic information system compared with artificial method. METHODS: The APACHEII score derived from critical clinical information system (simple called system score) from August 1st to September 1st 2013 were collected.Each of the results including overall score subtitle were compared with the corresponding score calculated through artificial method. RESULTS: there is big difference between the two methods both between overall score and subtitle score.overall score (193.4) vs.(127.6) (P=0.001); age: (161.4) vs.(159.6) (P=0.862); Temperature: (169.6) vs.(151.4) (P=0.027); MAP: (190.8) vs. (130.2) (P=0.001); HR: (181.8) vs.(139.3) (P=0.001); RR: (191.4) vs.(129.6) (P=0.001); PaO2: (152.5) vs. (168.5) (P=0.001); pH: (174.0) vs. (147.0) vs. (P=0.001); Na+: (161.5) vs.(159.6) (P=0.576); K+: (163.4) vs. (157.6) (P=0.457); CR: (177.2) vs (143.8) (P=0.001); HCT: (166.2) vs. (154.8) (P=0.199); WBC: (167.8) vs.(153.2) (P=0.054); Items of GCS and Organ Failure were not being compared. CONCLUSION: The APACHEII score obtained from critical clinic information system is more accurate and more objective.