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Using a Salop circle model, this research analyzes the welfare implications of firm/product entry with information provision by consumers. While firms use consumer information to target sales efforts, consumers face privacy trade‐offs when providing their personal information. We show that (i) price and profit first increase, then decrease with more varieties; (ii) consumer welfare, affected by price, sales effort, privacy loss, and matching effects, first decreases, then increases with firm entry; (iii) equilibrium information is socially optimal given the number of varieties; and (iv) if the variable cost of providing sales assistance is low (high), free entry leads to too much (few) varieties and too little (more) information, from a social welfare standpoint. [ABSTRACT FROM AUTHOR]

1,3,5-Trinitro-1,3,5-triazinane (RDX) has attracted considerable attention in energy-related fields. However, the safety performance of RDX needs to be improved in terms of various external stimuli. Herein, such issues of RDX could be well balanced through hydrothermal assembly with the assistance of insensitive 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) in a low content of 10 wt% (named RT co-particles). The TATB spread outside and were embedded inside of the resultant RT co-particles, which were examined via X-ray computed tomography and a three-dimensional laser scanning confocal microscope. As a result, the impact safety performance of RT co-particles could be drastically enhanced to 17.5 J by the TATB lubricant effect, demonstrating over twice the value of that of raw RDX (6 J) and mixtures (7 J). Moreover, an interfacial reconstruction between RDX and TATB was witnessed due to the strong interfacial interaction, as examined by theoretical simulation. Inspired by this, a delayed exothermic decomposition temperature of RT co-particles (244.4 °C) has been achieved when compared with that of RDX (241.4 °C). As demonstrated, an energetic co-particle strategy may provide an effective pathway toward remarkably improved mechanical and thermal safety performance, shedding light on other energetic materials. [ABSTRACT FROM AUTHOR]

PDGFR is an important target for novel anticancer therapeutics because it is overexpressed in a wide variety of malignancies. Recently, however, several anticancer drugs that inhibit PDGFR signaling have been associated with clinical heart failure. Understanding this effect of PDGFR inhibitors has been difficult because the role of PDGFR signaling in the heart remains largely unexplored. As described herein, we have found that PDGFR-β expression and activation increase dramatically in the hearts of mice exposed to load-induced cardiac stress. In mice in which Pdgfrb was knocked out in the heart in development or in adulthood, exposure to load-induced stress resulted in cardiac dysfunction and heart failure. Mechanistically, we showed that cardiomyocyte PDGFR-β signaling plays a vital role in stress-induced cardiac angiogenesis. Specifically, we demonstrated that cardiomyocyte PDGFR-β was an essential upstream regulator of the stress-induced paracrine angiogenic capacity (the angiogenic potential) of cardiomyocytes. These results demonstrate that cardiomyocyte PDGFR-β is a regulator of the compensatory cardiac response to pressure overload-induced stress. Furthermore, our findings may provide insights into the mechanism of cardiotoxicity due to anticancer PDGFR inhibitors., Introduction PDGF receptors and/or ligands are overexpressed in a wide variety of malignancies (1-4). In the past decade, a number of inhibitors of receptor tyrosine kinases (RTKs) whose targets include [...]

The energy release performance of energetic compounds like 3-nitro-1,2,4-trizole-5-one (NTO) and 5,5′-bistetrazole-1,1′-diolate (TKX-50) are indispensable in propellent formulations. However, thermal decomposition behavior is impeded by unfavorable catalysts. Presently, ultrathin porous MoS2 nanosheets (pMoS2) are considered as high-performance catalysts for NTO and TKX-50 decomposition. The pMoS2 in 5 wt% content could decrease the decomposition temperature of NTO and TKX-50 by 13.5 °C and 37.1 °C, respectively. Furthermore, the exothermic heat-release for pMoS2@NTO and pMoS2@TKX-50 were increased almost by a factor of two. The porous structure combined with large specific area of pMoS2 could mostly trigger the catalytic effect towards energetic compound decomposition. Additionally, the as-obtained MoS2 endowed advances in safety performance of NTO and TKX-50, with remarkably reduced impact and friction sensitivity. The as-proposed strategy may stimulate a different perspective towards the fast decomposition of energetic materials in propellants. [ABSTRACT FROM AUTHOR]

Mucosal healing requires migration and proliferation. Most studies of focal adhesion kinase (FAK), a protein that regulates motility, proliferation, and apoptosis, have focused on rapid phosphorylation. We reported lower FAK protein levels in motile Caco-2 colon cancer cells and postulated that this reduction in FAK available for activation might impact cell migration and mucosal healing. Therefore, total and active FAK (FA[K.sup.397]) immunoreactivity was assessed at the migrating fronts of human Caco-2 and rat IEC-6 intestinal epithelial cells. Caco-2 and IEC-6 motility, quantitated as migration into linear or circular wounds, was examined following FAK protein inhibition by small interfering RNA (siRNA). FAK protein stability and mRNA expression were ascertained by cycloheximide decay, RT-PCR, and in situ hybridization in static and migrating Caco-2 cells. Cells at the migrating front of Caco-2 and IEC-6 monolayers exhibited lower immunostaining for both total and activated FAK than cells immediately behind the front. Western blot analysis also demonstrated diminished FAK protein levels in motile cells by [greater than or equal to] 30% in both the differential density seeding and multiple scrape models, siRNA FAK protein inhibition enhanced motility in both the linear scrape (20% in Caco-2) and circular wound (16% in Caco-2 and 19% in IEC-6 cells) models. FAK protein degradation did not differ in motile and static Caco-2 cells and was unaffected by FA[K.sup.397] phosphorylation, but FAK mRNA was lower in migrating Caco-2 cells. Thus FAK protein abundance appears regulated at the mRNA level during gut epithelial cell motility and may influence epithelial cell migration coordinately with signals that modify FAK phosphorylation. healing; migration; restitution; ulcer doi:10.1152/ajpgi.00292.2005

Background: There are no obvious clinical signs and symptoms in the early stages of Alzheimer's disease (AD), and most patients usually have mild cognitive impairment (MCI) before diagnosis. Therefore, early diagnosis of AD is very critical. This paper mainly discusses the blood biomarkers of AD patients and uses machine learning methods to study the changes of blood transcriptome during the development of AD and to search for potential blood biomarkers for AD. Methods: Individualized blood mRNA expression data of 711 patients were downloaded from the GEO database, including the control group (CON) (238 patients), MCI (189 patients), and AD (284 patients). Firstly, we analyzed the subcellular localization, protein types and enrichment pathways of the differentially expressed mRNAs in each group, and established an artificial intelligence individualized diagnostic model. Furthermore, the XCell tool was used to analyze the blood mRNA expression data and obtain blood cell composition and quantitative data. Ratio characteristics were established for mRNA and XCell data. Feature engineering operations such as collinearity and importance analysis were performed on all features to obtain the best feature solicitation. Finally, four machine learning algorithms, including linear support vector machine (SVM), Adaboost, random forest and artificial neural network, were used to model the optimal feature combinations and evaluate their classification performance in the test set. Results: Through feature engineering screening, the best feature collection was obtained. Moreover, the artificial intelligence individualized diagnosis model established based on this method achieved a classification accuracy of 91.59% in the test set. The area under curve (AUC) of CON, MCI, and AD were 0.9746, 0.9536, and 0.9807, respectively. Conclusion: The results of cell homeostasis analysis suggested that the homeostasis of Natural killer T cell (NKT) might be related to AD, and the homeostasis of Granulocyte macrophage progenitor (GMP) might be one of the reasons for AD. [ABSTRACT FROM AUTHOR]

A novel thermally mendable polyurethane binder for energetic composites was designed and prepared via the Diels‐Alder (DA) cycloaddition reaction between a furan functionalized polycaprolactone (PCL) prepolymer and a bismaleimide compound. The structures and properties of synthesized PCL‐DA‐PU were fully characterized via Proton Nuclear Magnetic Resonance (1H‐NMR) and Fourier Transform Infrared spectroscopy (FT‐IR), Gel Permeation Chromatography (GPC), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC) measurements. As‐prepared material showed good self‐healing ability of scratches by virtue of combining the shape recovery effect of PCL segments favoring scratch closure with the re‐crosslinking of the cleaved DA bonds, which was evidenced by optical microscopy and tensile analysis. A scratch healing efficiency determined by tensile tests of about 89% was achieved. Moreover, with the contribution of DA bonds in PCL‐DA‐PU binder, the microcracks and other damages in the TATB based energetic composites were almost mended and the mechanical strength can recovery above 78%. [ABSTRACT FROM AUTHOR]

Energetic co-crystallization has been extensively explored as an effective strategy to balance the energy and sensitivity of energetic materials. In the present study, CL-20/HMX co-crystals with high purity, uniform morphology, well-proportioned size distribution, compact internal structure and reduced sensitivity were fabricated by a solvent-induced self-assembling approach using corresponding nanoparticles as the basic units. Such a CL-20/HMX co-crystal based on the self-assembly of a nano-explosive has been reported for the first time, providing a novel, high-yield, general and easily scaled-up method for the fabrication of energetic co-crystals. Notably, the formation processes of the as-synthesized co-crystals were determined as interfacial self-assembly at nanoparticle scale instead of the complete dissolution and nucleation process at the molecular level as observed with the traditional recrystallization technique. The completely formed CL-20/HMX co-crystal structure with few separate-assembled CL-20 or HMX crystals was charecterized by PXRD, TG-DSC, Raman, FT-IR, DG and SCXRD analyses. Additionally, the formation of intermolecular hydrogen bonds was confirmed by Terahertz (THz) analysis. The typical Avrami equation was constructed for modeling the kinetics of the assembly of CL-20/HMX co-crystals, and the self-assembly process can be generally summarized as the induction of nano-particles, oriented aggregation, surface integration and single co-crystal formation. [ABSTRACT FROM AUTHOR]

Mechanical performance is significant for the application of pressed polymer bonded explosives (PBXs) materials. In this research, several types of 2,6‐diamino‐3,5‐dinitropyrazine‐1‐oxide (LLM‐105) were selected to study the effects of crystal quality and morphology on the mechanical performance of LLM‐105 based PBXs. The surface bonding status of the LLM‐105 crystal and molding powder was characterized by scanning electron microscopy (SEM) and contact angle analysis, and the moldability was evaluated by determining the relative density of pressed cylinders of corresponding PBXs. Besides, static and dynamic mechanical properties were studied and compared, presenting the compressive, tensile and creep curves. For LLM‐105 based PBXs, spherical morphology and rough surface could result improved mechanical strength and creep resistance, facilitating the structural and dimensional stability of charges. In this case, it can bring benefits for their reliability and safety performances during application. [ABSTRACT FROM AUTHOR]

In this work, a series of TATB-based aluminized explosives were formulated from 1, 3, 5-triamino-2, 4, 6-trinitrobenzene (TATB), aluminum powders and polymeric binders. The thermal stability, heat of detonation, detonation velocity and pressure of the TATB based aluminized (TATB/Al) explosives were systematically investigated by cook-off, constant temperature calorimeter, electrometric method and manganin piezo resistance gauge, respectively. The selected PBX-3 (70 wt% TATB/25 wt% Al/5 wt% fluorine resin) achieved optimized balance between thermal stability and detonation performance, with the thermal runaway temperature around 583 K. The thermal ignition of TATB-based aluminized explosive occurred at the edge of the cylinder according to the experimental and numerical simulations. Moreover, the critical thermal runaway temperature for PBX-3 was calculated based on the Semenov's thermal explosion theory and the thermal decomposition kinetic parameters of the explosive, which was consistent with the experimental value. [ABSTRACT FROM AUTHOR]

In this work, inspired by the strong chemical adhesion of mussels, a facile and noncovalent in situ polymerization of dopamine approach has been employed to coat 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) crystals. The resultant polydopamine (PDA) coated TATB (pTATB) core–shell particles are subjected to in-depth characterizations. It has been demonstrated that a dense graphite-like structure PDA is uniformly coated on the surfaces of TATB crystals. By optimization of the reaction time, pH value and temperature, the morphology and thickness of the PDA layer on TATB crystals were finely controlled on a nanometer scale. Then, the pTATB was further used as the solid filler of a typical polymer bonded explosive (PBX). It has been shown that the PBX containing pTATB exhibited significantly improved tensile and compression strength or strain, and creep resistance, due to the strong interfacial interactions at the PDA interlayer. Moreover, the mechanical properties could be further improved by using more PDA content. This work demonstrates an effective and fundamental surface modification method to enhance the interfacial interaction between crystalline particles and binders, resulting in improved mechanical properties. [ABSTRACT FROM AUTHOR]

Inspired by the strong chemical adhesion of mussels, the polymerization of dopamine was first introduced to coat energetic organic crystals through a simple immersion method. 1,3,5,7-Tetranitro-1,3,5,7-tetraazacyclooctane (HMX) was used as substrate. In-depth characterizations confirmed a compact core–shell formation with a dense graphite-like structure PDA on every HMX crystal. The phase transition temperature of the crystals (β phase → δ phase) was improved by 27.5 °C for HMX enabled in 0.5 wt% PDA. In situ XRD showed that 94.8% of β-HMX was transformed to δ-HMX, whereas only 14.7% of β-HMX was transformed in HMX with 2.1% PDA at 210 °C. The heated HMX/PDA crystals (210 °C, 30 min) retained primary morphology, with intact PDA shell, demonstrating the excellent ability of PDA to prevent thermal damage in energetic crystals. The impact sensitivities of HMX and HMX/PDA were tested by Bundesanstalt für Materialprüfung (BAM) method. No difference between HMX (impact energy: 5.0 J) and HMX/PDA (5.0 J) at room temperature was attributed to the rigid PDA shell, which was benefit for phase transition, but inefficient for reducing sensitivity. After being heated at 200 °C for 30 min, the impact energy of HMX showed a dramatically drop (2.0 J), while that of HMX/PDA unchanged (5.0 J), indicating the increased sensitivity of HMX after thermal damage, and retardation of phase transition is benefit for the safety of polymorph explosives. This work demonstrates the successful application of dopamine chemistry to energetic materials, thereby providing a potential method for the modification of energetic crystals. [ABSTRACT FROM AUTHOR]

This paper develops a duopoly model where broadcasters first choose their program quality and then their pricing strategy. Two alternative financing schemes are considered: pay-TV and free-to-air. We find that, from a welfare perspective, a pay-TV regime always generates inadequate quality and advertising, whereas free-to-air might produce excessive quality and advertising. In the case of asymmetric competition, a pay-TV broadcaster always has a stronger incentive to conduct research and development than a free-to-air broadcaster does. Both platforms could either over- or underinvest. The pay-TV broadcaster always shows too few advertisements, but the free-to-air media might act in the opposite manner. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of binder component on the creep properties of polymer-bonded explosive (PBX), three-point bending creep behaviors of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)-based PBX and its styrene copolymer modified formulation were studied by dynamic mechanical analyzer. The experimental results showed that owing to the addition of reinforcing agent (styrene copolymer) with high glass transition temperature and high mechanical strength, the creep resistance performance of the modified formulation was improved with reduced creep strain and constant creep rate and prolonged creep failure time. A six-element mechanical model was applied to simulate the creep behaviors of TATB-based PBX and its modified formulation. The constitutive equation of creep curves under different conditions were obtained by nonlinear fit. The predicted theoretical results coincided quite well with the experimental data. [ABSTRACT FROM AUTHOR]