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On defining partition entropy by inequalities
Partition entropy is the numerical metric of uncertainty within
a partition of a finite set, while conditional entropy measures the degree of
difficulty in predicting a decision partition when a condition partition is
provided. Since two direct methods exist for defining conditional entropy
based on its partition entropy, the inequality postulates of monotonicity,
which conditional entropy satisfies, are actually additional constraints on
its entropy. Thus, in this paper partition entropy is defined as a function
of probability distribution, satisfying all the inequalities of not only partition
entropy itself but also its conditional counterpart. These inequality
postulates formalize the intuitive understandings of uncertainty contained
in partitions of finite sets.We study the relationships between these inequalities,
and reduce the redundancies among them. According to two different
definitions of conditional entropy from its partition entropy, the convenient
and unified checking conditions for any partition entropy are presented, respectively.
These properties generalize and illuminate the common nature
of all partition entropies
Forchheimer flow to a well-considering time-dependent critical radius
Previous studies on the non-Darcian flow into a pumping well assumed that
critical radius (RCD) was a constant or infinity, where RCD
represents the location of the interface between the non-Darcian flow region
and Darcian flow region. In this study, a two-region model considering
time-dependent RCD was established, where the non-Darcian flow was
described by the Forchheimer equation. A new iteration method was proposed
to estimate RCD based on the finite-difference method. The results
showed that RCD increased with time until reaching the quasi steady-state flow, and the asymptotic value of RCD only depended on the
critical specific discharge beyond which flow became non-Darcian. A larger
inertial force would reduce the change rate of RCD with time, and
resulted in a smaller RCD at a specific time during the transient flow.
The difference between the new solution and previous solutions were obvious
in the early pumping stage. The new solution agreed very well with the
solution of the previous two-region model with a constant RCD under
quasi steady flow. It agreed with the solution of the fully Darcian flow
model in the Darcian flow region
Etanercept Inhibits Pro-inflammatory Cytokines Expression in Titanium Particle-Stimulated Peritoneal Macrophages
Purpose: To investigate the inhibitory role of Etanercept in pro-inflammatory cytokines such as TNF-α, IL-1β and IL-6 production in titanium (Ti) particle stimulated macrophages.Methods: Peritoneal macrophages were stimulated with 1 × 109 Ti particles and treated simultaneously with or without 10, 100, or 1000 ng/mL Etanercept. The levels of TNF-α, IL-1β and IL-6 in the culture supernatants were measured using ELISA.Results: Titanium particles could stimulate TNF-α, IL-1β and IL-6 secretion in peritoneal macrophages. Etanercept inhibited Ti particle-induced TNF-α release by 29.7 % at 10 ng/ml (19.19 ± 4.72 pg/mL, p < 0.01), 49.3 % at 100 ng/mL (13.83 ± 3.72 pg/ml, p < 0.01) and 60.4 % at 1000 ng/mL (10.82 ± 3.87 pg/mL, p < 0.001), IL-1β release by 5.23 % at 10 ng/mL (34.79 ± 7.83 pg/mL, p > 0.05), 21.06 % at 100 ng/mL (28.98 ± 4.81 pg/mL, p < 0.01) and 29.83 % at 1000 ng/mL (25.76 ± 5.23 pg/ml, p < 0.001), and IL-6 release by 38.69 % at 10 ng/mL (256.8 ± 99.56 pg/mL, p < 0.01), by 42.13 % at 100 ng/mL (242.4 ± 33.26 pg/mL, p < 0.01) and 53.4 % at 1000 ng/ml (195.2 ± 48.82 pg/mL, p < 0.001).Conclusion: Etanercept has potent ability to prevent wear debris–induced osteolysis and may be valuable as a therapeutic agent for the treatment of prosthetic loosening in humans.Keywords: Etanercept; titanium particle; proinflammatory cytokines; peritoneal macrophage
Forchheimer flow to a well-considering time-dependent critical radius
Previous studies on the non-Darcian flow into a pumping well assumed that
critical radius (RCD) was a constant or infinity, where RCD
represents the location of the interface between the non-Darcian flow region
and Darcian flow region. In this study, a two-region model considering
time-dependent RCD was established, where the non-Darcian flow was
described by the Forchheimer equation. A new iteration method was proposed
to estimate RCD based on the finite-difference method. The results
showed that RCD increased with time until reaching the quasi steady-state flow, and the asymptotic value of RCD only depended on the
critical specific discharge beyond which flow became non-Darcian. A larger
inertial force would reduce the change rate of RCD with time, and
resulted in a smaller RCD at a specific time during the transient flow.
The difference between the new solution and previous solutions were obvious
in the early pumping stage. The new solution agreed very well with the
solution of the previous two-region model with a constant RCD under
quasi steady flow. It agreed with the solution of the fully Darcian flow
model in the Darcian flow region
QUANTIFYING THE RELATIONSHIP BETWEEN NATURAL AND SOCIOECONOMIC FACTORS AND WITH FINE PARTICULATE MATTER (PM2.5) POLLUTION BY INTEGRATING REMOTE SENSING AND GEOSPATIAL BIG DATA
PM2.5 pollution is an environmental issue results from various natural and socioeconomic factors, frequently witnessed in the spring and winter across mainland China. However, the dominant influence of natural and socioeconomic factors within a city on PM2.5 is not extensively studied yet. In this study, the Random Forest Regression (RFR) is utilized to quantify the relationships between PM2.5 and potential factors within Wuhan city on a typical day turn from winter to spring. Technically, the 24-hour average PM2.5 concentration in downtown area on February 17th 2017 are collected at 9 sites. In the meantime, we retrieve simultaneous aerosol depth optical depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS). The ground measured PM2.5 and AOD are coupled for the retrieval of near-surface PM2.5 concentration by Spatial-temporal CoKriging (STCK) with Normalized Vegetation Index (NDVI), Modified Normalized Water Index (MNDWI), Normalized Building Index (NDBI) from Landsat-8 and DEM from Shuttle Radar Topography Mission (SRTM). As the geospatial big data booms, the Internet-collected volunteered geographic information (VGI), representing the urban form and function, are integrating for the regression to obtain the spatial variables importance measures (VIMs) by RFR both in centre and sub-urban region of Wuhan. The results reveal that terrain characteristics and the density of industrial enterprises have obvious relationships with the accumulation of PM2.5 while the density of roads also contributes to this
Au plasmonics in a WS2-Au-CuInS2 photocatalyst for significantly enhanced hydrogen generation
Promoting the activities of photocatalysts is still the critical challenge in H2 generation area. Here, a Au plasmon enhanced photocatalyst of WS2-Au-CuInS2 is developed by inserting Au nanoparticles between WS2 nanotubes and CuInS2 (CIS) nanoparticles. Due to the localized surface plasmonic resonance properties from Au nanoparticles, WS2-Au-CIS shows the best performance as compared to Au-CIS, CIS, WS2-CIS, CIS-Au, WS2-Au, and WS2-CIS-Au. The surface plasmonic resonance effects dramatically intensify the absorption of visible light and help to inject hot electrons into the semiconductors. Our findings open up an efficient method to optimize the type-II structures for photocatalytic water splitting
Obvious enhancement of the total reaction cross sections for P with Si target and the possible relavent mechanisms
The reaction cross sections of P and the corresponding isotones on
Si target were measured at intermediate energies. The measured reaction cross
sections of the N=12 and 13 isotones show an abrupt increase at . The
experimental results for the isotones with as well as P can
be well described by the modified Glauber theory of the optical limit approach.
The enhancement of the reaction cross section for P could be explained
in the modified Glauber theory with an enlarged core. Theoretical analysis with
the modified Glauber theory of the optical limit and few-body approaches
underpredicted the experimental data of P. Our theoretical analysis
shows that an enlarged core together with proton halo are probably the
mechanism responsible for the enhancement of the cross sections for the
reaction of P+Si.Comment: 16 pages, 5 figures, to be published in Phys.Rev.
Receptor interactive protein kinase 3 promotes cisplatin-triggered necrosis in apoptosis-resistant esophageal squamous cell carcinoma cells
Cisplatin-based chemotherapy is currently the standard treatment for locally advanced esophageal cancer. Cisplatin has been shown to induce both apoptosis and necrosis in cancer cells, but the mechanism by which programmed necrosis is induced remains unknown. In this study, we provide evidence that cisplatin induces necrotic cell death in apoptosisresistant esophageal cancer cells. This cell death is dependent on RIPK3 and on necrosome formation via autocrine production of TNFα. More importantly, we demonstrate that RIPK3 is necessary for cisplatin-induced killing of esophageal cancer cells because inhibition of RIPK1 activity by necrostatin or knockdown of RIPK3 significantly attenuates necrosis and leads to cisplatin resistance. Moreover, microarray analysis confirmed an anti-apoptotic molecular expression pattern in esophageal cancer cells in response to cisplatin. Taken together, our data indicate that RIPK3 and autocrine production of TNFα contribute to cisplatin sensitivity by initiating necrosis when the apoptotic pathway is suppressed or absent in esophageal cancer cells. These data provide new insight into the molecular mechanisms underlying cisplatin-induced necrosis and suggest that RIPK3 is a potential marker for predicting cisplatin sensitivity in apoptosis-resistant and advanced esophageal cancer. © 2014 Xu et al
The active fault belts in eastern Tibet margin inferred using magnetotellurics
A magnetotelluric (MT) sounding has been carried out in the eastern margin of the Tibetan plateau. The survey line is about 145 km long, trending in NEE direction and crossing the Daliangshan block in the eastern edge of the Tibetan plateau. The field measurements acquired effective data of 68 sites. Through data processing and a 2-D inversion with consideration of topography, a 2-D electrical structure model of crust and upper mantle was constructed. The structure reveals that there is a deep electrical boundary between the Daliangshan block in the west and Sichuan block in the east. West to the boundary, the crust has a relatively low resistivity with respect to the east and can be divided into three layers, the middle layer has low resistivity with a minimum of 3-10 W•m, presumably associated with partial melt and/or salty fluids. Beneath the intersection area of the Anninghe fault, the Xianshuihe fault and the Longmenshan fault, which the MT profile crosses, the faults are separated into upper and lower sections. The upper section exhibits a nearly vertical low-resistivity zone in the upper crust, and the lower section manifests an electrical boundary in the lower crust and upper mantle. Other faults in the Daliangshan block are either nearly vertical low-resistivity zones or electrical boundaries. It is suggested that the formation of the low-resistivity layer in the middle crust is associated with the southeastward motion of the eastern margin of the Tibetan plateau, clockwise rotation of the Chuandian (Sichuan-Yunnan) block, and the westward obstruction from the Sichuan block in Huanan terrain. Seismicity, including the M 8.0 Wenchuan earthquake in the study area, is discussed
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