20 research outputs found
Online Voltage Stability Assessment for Load Areas Based on the Holomorphic Embedding Method
This paper proposes an online steady-state voltage stability assessment
scheme to evaluate the proximity to voltage collapse at each bus of a load
area. Using a non-iterative holomorphic embedding method (HEM) with a proposed
physical germ solution, an accurate loading limit at each load bus can be
calculated based on online state estimation on the entire load area and a
measurement-based equivalent for the external system. The HEM employs a power
series to calculate an accurate Power-Voltage (P-V) curve at each load bus and
accordingly evaluates the voltage stability margin considering load variations
in the next period. An adaptive two-stage Pade approximants method is proposed
to improve the convergence of the power series for accurate determination of
the nose point on the P-V curve with moderate computational burden. The
proposed method is illustrated in detail on a 4-bus test system and then
demonstrated on a load area of the Northeast Power Coordinating Council (NPCC)
48-geneartor, 140-bus power system.Comment: Revised and Submitted to IEEE Transaction on Power System
Yiguanjian cataplasm attenuates opioid dependence in a mouse model of naloxone-induced opioid withdrawal syndrome
AbstractObjectiveTo investigate the effect of Yiguanjian (YGJ) cataplasm on the development of opioid dependence in a mouse model of naloxone-induced opioid withdrawal syndrome.MethodsOne hundred Swiss albino mice, of equal male to female ratio, were randomly and equally divided into 10 groups. A portion (3 cm2) of the backside hair of the mice was removed 1 day prior to the experiment. Morphine (5 mg/kg) was intraperitoneally administered twice daily for 5 days. YGJ cataplasm was prepared and pasted on the bare region of the mice immediately before morphine administration on day 3 and subsequently removed at the end day 5. On day 6, naloxone (8 mg/kg) was intraperitoneally injected to precipitate opioid withdrawal syndrome. Behavioral observation was performed in two 30-min phases immediately after naloxone injection.ResultsThe YGJ cataplasm significantly and dose-dependently attenuated morphine-naloxone-induced experimental opioid withdrawal, in terms of withdrawal severity score and the frequencies of jumping, rearing, forepaw licking, and circling behaviors. However, YGJ cataplasm treatment did not alter the acute analgesic effect of morphine.ConclusionYGJ cataplasm could attenuate opioid dependence and its associated withdrawal symptoms. Therefore, YGJ cataplasm could serve as a potential therapy for opioid addiction in the future
IIS: Intelligent identification scheme of massive IoT devices
Device identification is of great importance in system management and network security. Especially, it is the priority in industrial internet of things (IIoT) scenario. Since there are massive devices producing various kinds of information in manufacturing process, the robustness, reliability, security and real-time control of the whole system is based on the identification of the massive IIoT devices. Previous IIoT device identification solutions are mostly based on a centralized architecture, which brings a lot of problems in scalability and security. In addition, most traditional identification systems can only identify inherent types of devices which is not suitable for the adaptive device management in IIoT. In order to solve these problems, this paper proposes a Intelligent Identification Scheme(IIS) of Massive IoT Devices, a completely distributed intelligent identification scheme of massive IIoT devices. The scheme changes the traditional centralized architecture and realizes more efficient clustering identification of massive IIoT devices. Moreover, IIS can identify more and more types of devices intelligently with the continuous learning ability since the identification model is constantly updated according to the ledger which is maintained by all gateways collaboratively. We also conduct experiments to evaluate the performance of IIS based on the data obtained from real IIoT devices, which proves that IIS is efficient in device identification and intelligent for the adaptive device management in IIoT
Interleukin-6 Promotes Epithelial-Mesenchymal Transition and Cell Invasion through Integrin β6 Upregulation in Colorectal Cancer
The metastatic potential of colorectal cancer (CRC) is intensively promoted by the tumor microenvironment (TME) in a paracrine manner. As a pleiotropic inflammatory cytokine, Interleukin-6 (IL-6) is produced and involved in CRC, the same scenario where integrin αvβ6 also becomes upregulated. However, the relationship between IL-6 and integrin αvβ6 as well as their involvement in the crosstalk between CRC and TME remains largely unclear. In the present study, we demonstrated a positive correlation between the expression of IL-6 and integrin β6 in CRC samples. The mutually promotive interaction between CRC and TME was further determined by an indirect coculture system. CRC cells could augment the secretion of IL-6 from fibroblasts, which in return induced invasion and integrin β6 expression of CRC cells. Through the classic IL-6 receptor/STAT-3 signaling pathway, IL-6 mediated the upregulation of integrin β6, which was involved in the invasion and epithelial-mesenchymal transition of CRC cells induced by IL-6. Taken together, our results reveal a paracrine crosstalk between IL-6 signals originating from the TME and increased the integrin β6 level of CRC. IL-6 induces CRC invasion via upregulation of integrin β6 through the IL-6 receptor/STAT-3 signaling pathway. Combined inhibition of IL-6 along with integrin β6-targeted strategy may indicate new directions for antitumor strategies for CRC
Towards a Better Understanding of Long-Term Self-Forming Dynamic Membrane Bioreactor (SFDMBR) Performance: Effect of Aeration Intensity
This study aims to provide valuable new insights regarding the effect of aeration intensity on long-term self-forming dynamic membrane bioreactor (SFDMBR) performance and the associated mechanisms. Three identical SFDMBRs, with different aeration intensities (i.e., 200, 500 and 800 L/h), were operated in constant transmembrane (TMP) mode for 60 days. The best chemical oxygen demand (COD) removal performance was achieved at medium aeration intensity, owing to the enhanced COD removal contribution by the self-forming dynamic membrane (SFDM). As expected, the SFDM formation time was extended with increasing aeration intensity. Different from the initial short-term stage results, it was interestingly found that the SFDMBR operated at medium aeration intensity exhibited the best long-term filtration performance, followed in order by the SFDMBRs with low and high aeration intensity, respectively. Further analysis revealed that the governing fouling mechanism transited from biomass accumulation to the increase of specific resistance, as aeration intensity increased. The variation of SFDM-specific resistance was verified with particle size distribution (PSD) data and scanning electron microscopy (SEM) images. The long-term increasing rate of SFDM filtration resistance was consistent with both extracellular polymeric substances (EPS) content and the proteins/polysaccharides (PN/PS) ratio of SFDMs. Internal EPS production was enhanced in the thicker SFDM formed at a lower aeration intensity
Biobased Anethole/Polyacrylate Cross-Linked Materials with Good Transparency and High Thermostability
A series of new thermo-cross-linkable
polymers with both excellent
transparency and thermostability derived from a biorenewable plant
oil (anethole) are reported here. By using the plant oil as the feedstock,
a new monomer (anethole-based acrylate) containing propenyl and acryloyl
functional units is successfully synthesized via a simple two-step
reaction route. Copolymerizing the monomer with methyl acrylate (<b>MA</b>) in the presence of radical initiator gives the copolymers,
which are postpolymerized at high temperature to form the polymers,
exhibiting the thermostability and the transmittance depending on
the content of the anethole-based acrylate. With the increasing of
the content of the anethole-based acrylate, the thermostability of
the cross-linked polymers raises while the transparency decreases.
The best results are obtained when the molar ratio between methyl
acrylate and anethole-based acrylate is 2:1. In that case, the cured
polymer shows a glass transition temperature (<i>T</i><sub>g</sub>) of 148 °C and a coefficient of thermal expansion (CTE)
of 152.58 ppm/°C, as well as high transparency with the transmittance
of more than 92% from 450 to 1100 nm. These data exhibit that the
new acrylate-containing polymers derivated from a biorenewable can
be used as the high performance optical materials with both good transparency
and high thermostability
Conversion of a Biorenewable Plant Oil (Anethole) to a New Fluoropolymer with Both Low Dielectric Constant and Low Water Uptake
The
conversion of a biorenewable plant oil (anethole) to a new
fluoropolymer with both low dielectric constant and low water uptake
is reported here. First, cationic polymerization of plant oil by using
CF<sub>3</sub>SO<sub>3</sub>H as an initiator gave a polymer, which
was then functionalized by introducing the thermocrosslinkable -OCFî—»CF<sub>2</sub> groups via a three-step procedure. The obtained fluoropolymer
can be easily thermally converted to an infusible and insoluble cross-linked
network exhibiting low water uptake (<0.24%, in water of 96 °C
for 4 days) and low dielectric constant (<2.64 at a range of frequencies
varying from 1.0 to at 30 MHz at room temperature). TGA and DMA data
showed that the cross-linked network had 5 wt % loss temperature of
400 °C (in N<sub>2</sub>) and a <i>T</i><sub>g</sub> of 160 °C, respectively. Nanoindentation tests indicated that
the cross-linked film had an average hardness of 0.239 GPa and a Young’s
modulus of 6.11 GPa. These results mean that the new polymer derived
from biorenewable anethole is comparable to the petroleum-based materials,
implying that the low <i>k</i> polymers widely utilized
in microelectronic industry will have a new sustainable feedstock
supply