We use probit recession forecasting models to assess the ability of economic policy uncertainty indexes developed by Baker et al. (2013) to predict future US recessions. The model specifications ...include policy indexes on their own, and in combination with financial variables, such as interest rate spreads, stock returns and stock market volatility. Both in-sample and out-of-sample analysis suggests that the policy uncertainty indexes are statistically and economically significant in forecasting recessions at the horizons beyond five quarters. The index based on newspaper reports emerges as the best predictor, outperforming the term spread at the longer forecast horizons.
•Economic policy uncertainty indexes (IEPU) help predict future US recessions.•IEPUs improve forecasts from probit models with financial variables.•The results hold for in-sample and out-of-sample forecasts at longer horizons.•The newspaper-based index is a robust predictor at the longer forecast horizons.
Flexible battery-type in-plane hybrid micro-supercapacitors (IHMSCs), which combine fast charging rate of micro-supercapacitors and high energy density of batteries, provide great potentials for ...flexible microdevices. However, their low-efficiency, high-cost process and limited energy density still hinder their practical applications. Herein, we report the high-efficient fabrication of Fe3O4 nanoparticle-anchored laser-induced graphene (LIG/Fe3O4) with hierarchical porous structures on a flexible substrate wherein aggregated Fe3O4 nanoparticles (~24.08 nm) with mesopores are self-deposited onto macroporous LIG scaffolds by laser in one step. The unique 3D structures in LIG/Fe3O4 give rise to superhydrophilic and capillary effects with a pumping capacity of up to 0.096 μm in water, resulting in continuous superior wettability between electrodes and water-based electrolyte. Benefiting from the reversible H+ ion (de)intercalation reaction with Fe3O4 nanoparticles, the resulting IHMSCs based on LIG/Fe3O4 as the anode and LIG as the cathode deliver an ultrahigh areal capacitance of 719.28 mF/cm2, which is over 100 times higher than that of LIG micro-supercapacitors, and an areal energy density of 60.20 μWh/cm2, superior to those of most previously reported IHMSCs. Furthermore, the IHMSCs exhibit a good cycling stability and mechanical flexibility. Our method is applicable to other capillary-functionalized flexible electronics and may open new avenues for large-scale industrial fabrication of flexible electronics.
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•High-efficient fabrication of Fe3O4 nanoparticle-anchored porous graphene (LIG/Fe3O4) on flexible substrate is achieved.•Self-deposition of aggregated Fe3O4 nanoparticles with mesopores onto macroporous graphene is conducted by direct laser writing.•The hierarchical pore structures give rise to superhydrophilic and excellent capillary effects in water.•The LIG/Fe3O4 in-plane micro-supercapacitors (IMSCs) deliver an capacitance of 719 mF/cm2, superior to those of most reported IMSCs.
The power electronics industry has been actively seeking high temperature stable epoxy molding compound (EMC) materials that can meet the requirements for encapsulating future SiC chips operating at ...a temperature (250 °C) that exceeds the capability of current epoxy chemistry. This work provides a detailed evaluation of a high heat resistant cyanate ester (CE)/epoxidized cresol novolac (ECN) copolymer system with varied compositions regarding their high temperature performances. Owing to the novolac nature of ECN which provides a high crosslink density, it is found that the copolymers with a low CE concentration (25–33 mol%) are able to produce a comparable glass transition temperature (>230 °C) and decomposition temperature (T10%>400 °C) to those of the high CE formulations. Moreover, long-term high temperature (250 °C) storage test of reveals a less severe weight loss and blistering in the lower CE formulations. A distinguished degradation mechanism involving hydrolysis of unreacted cyanate groups in the high CE compositions was determined through various thermal and chemical analyses. It was concluded that the CE/ECN copolymers with low CE concentrations are promising candidates for the high temperature EMC formulation.
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•Curable cyanate ester (CE)/epoxidized cresol novolac (ECN) copolymers with varied compositions were prepared.•High glass transition temperature (>230 °C) and decomposition temperature (T10% > 400 °C) was achieved in low CE formulations.•High temperature (250 °C) aging revealed poor stability of high CE formulations due to several hydrolysis degradation.•Overall, 25 mol%~33 mol% of CE concentration produced best copolymer for high temperature encapsulant applications.
We demonstrate, for the first time, an ultra-low-noise mode-division multiplexed transmission with eight wavelength-division multiplexed channels over a 100-km few-mode fiber based on a second-order ...few-mode Raman amplifier. To minimize the mode dependent gain, two backward depolarized pumps at the wavelengths of 1455 nm (75 mW) and 1360 nm (1890 mW) are equally launched both into the LP 11a and LP 11b modes. The Raman on-off gains of the LP 01 and LP 11 modes are both above 8 dB and the mode dependent gain is less than 0.7 dB. An amplified spontaneous emission noise improvement of 1.8 dB is achieved in the second-order few-mode Raman amplifier, with respect to the first-order Raman amplification. The effective noise figure of the second-order few-mode Raman amplifier is about -3 dB, which is ~1.4 dB lower than that in the first-order pumping case. In the transmission experiments, a single-mode transmission over LP 01 mode and a mode-division multiplexed transmission over LP 11a and LP 11b modes are performed separately. The bit-error-rates for all the transmission channels are significantly improved due to the low-noise figure amplification of the second-order few-mode Raman amplifier.
Oridonin (ORI) could inhibit the proliferation and induce apoptosis in various cancer cell lines. However, the mechanism is not fully understood.
Human prostate cancer (HPC) cells were cultured in ...vitro and cell viability was detected by the CCK-8 assay. The ultrastructure changes were observed under transmission electron microscope (TEM). Chemical staining with acridine orange (AO), MDC or DAPI was used to detect acidic vesicular organelles (AVOs) and alternation of DNA. Expression of LC3 and P21 was detected by Western Blot. Apoptotic rates and cell cycle arrest were detected by FACS.
Our study demonstrated that after ORI treatment, the proliferations of human prostate cancer (HPC) cell lines PC-3 and LNCaP were inhibited in a concentration and time-dependent manner. ORI induced cell cycle arrest at the G2/M phase. A large number of autophagosomes with double-membrane structure and acidic vesicular organelles (AVOs) were detected in the cytoplasm of HPC cells treated with ORI for 24 hours. ORI resulted in the conversion of LC3-I to LC3-II and recruitment of LC3-II to the autophagosomal membranes. Autophagy inhibitor 3-methyladenine (3-MA) reduced AVOs formation and inhibited LC3-I to LC3-II conversion. At 48 h, DNA fragmentation, chromatin condensation and disappearance of surface microvilli were detected in ORI-treated cells. ORI induced a significant increase in the number of apoptotic cells (PC-3: 5.4% to 27.0%, LNCaP: 5.3% to 31.0%). Promoting autophagy by nutrient starvation increased cell viability, while inhibition of autophagy by 3-MA promoted cell death. The expression of P21 was increased by ORI, which could be completely reversed by the inhibition of autophagy.
Our findings indicated that autophagy occurred before the onset of apoptosis and protected cancer cells in ORI-treated HPC cells. P21 was involved in ORI-induced autophagy and apoptosis. Our results provide an experimental basis for understand the anti-tumor mechanism of ORI as treatment for prostate cancer.
Coffee shell is an environmental concern to china along with steady growth of coffee production. This study attempt to characterize high specific surface area activated carbon (HSSA-AC). HSSA-AC was ...prepared from carbonized material which obtained from coffee shell by microwave irradiation. Textural properties and surface chemistry of HSSA-AC were found to be strongly depending on the activation time, KOH/C ratio and particle size. The textural properties of the samples were investigated by means of scanning electron microscope analyzer (SEM), cryogenic N2 adsorption, whereas, surface chemistry was probed through Fourier Transform Infrared (FTIR) spectrometer (Maldhure and Ekhe, 2011) and Hydrogen storage performance was tested by H2 adsorption. Maximum surface area of 3149 m2 g−1, Iodine adsorption value 2566 mg/g, Methylene Blue adsorption value 47.5 mL 0.1 g−1, the hydrogen adsorption value 0.91 wt% at 14 MPa and yield 39% was observed in case of microwave treated sample at activation time 9 min, KOH/C ratio 5 and particle size 0.25–0.71 mm. Results revealed usefulness of microwave treatment in influencing surface area of HSSA-AC which could be used in a hydrogen storage material research application.
To develop a computational method for oxygen-saturation-related functional parameter analysis of retinal vessels based on traditional color fundus photography, and to explore their characteristic ...alterations in type 2 diabetes mellitus (DM).
50 type 2 DM patients with no-clinically detectable retinopathy (NDR) and 50 healthy subjects were enrolled in the study. An optical density ratio (ODR) extraction algorithm based on the separation of oxygen-sensitive and oxygen-insensitive channels in color fundus photography was proposed. With precise vascular network segmentation and arteriovenous labeling, ODRs were acquired from different vascular subgroups, and the global ODR variability (ODR
) was calculated. Student's t-test was used to analyze the differences of the functional parameters between groups, and regression analysis and receiver operating characteristic (ROC) curves were used to explore the discrimination efficiency of DM patients from healthy subjects based on these functional parameters.
There was no significant difference in the baseline characteristics between the NDR and healthy normal groups. The ODRs of all vascular subgroups except the micro venule were significantly higher (
, respectively) while ODR
was significantly lower (
) in NDR group than that in healthy normal group. In the regression analysis, the increased ODRs except micro venule and decreased ODR
were significantly correlated with the incidence of DM, and the C-statistic for discrimination DM with all ODR is 0.777 (95% CI 0.687-0.867,
).
A computational method to extract the retinal vascular oxygen-saturation-related optical density ratios (ODRs) with single color fundus photography was developed, and increased ODRs and decreased ODR
of retinal vessels could be new potential image biomarkers of DM.
The cellulose fiber was extracted from the abandoned crop sugarcane bagasse (SCB) by means of chemical treatment methods. Poly(lactic acid) (PLA) bio‐based composites with SCB were prepared through ...fused deposition modeling (FDM) 3D‐printing technology, and the morphologies, mechanical properties, crystallization properties, and thermal stability of 3D‐printed composites were investigated. Compared with the neat PLA, the incorporation of SCB into PLA reduces the tensile strength and flexural strength of 3D‐printed samples but increases the flexural modulus. The difference in tensile performance and bending performance is that the tensile strength of 3D‐printed samples is best when the SCB content is 6 wt%, while the flexural modulus continuously decreases as the SCB content increases. Furthermore, the effects of various printing methods on the tensile performance of 3D‐printed samples were explored via modifying G‐code of 3D models. The results indicate that the optimum SCB fiber content is identical for all printing methods except method “vertical.” Due to the fibers and molecular chains are oriented to varying degrees with altering raster angle in 3D‐printed samples, the fully oriented sample printed by method “parallel” has a better tensile strength. Besides, SCB exhibits enough high thermal decomposition temperature to meet requirements for melt extrusion processing of PLA composites, and SCB fiber is capable of promoting the crystallization of PLA.
We demonstrate a novel method for obtaining high spatial resolution optical frequency domain reflectometry (OFDR) utilizing recirculating frequency shifter for broadening the optical frequency ...sweeping. Twelve times broadened optical frequency sweeping is achieved. We obtain 0.97 cm spatial resolution over 710-m measurement range with modulation frequency sweeping span of 882 MHz. Such a spatial resolution corresponds to a frequency sweeping span of 10.31 GHz. The experimental results indicate that the measurement range can be extended to 10 km, based on the proposed method.
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