Highlights • The levels of retinal GABA, GABAA and GABAC receptors are up-regulated in myopia. • EA inhibits the up-regulation of retinal GABA, GABAA and GABAC receptors in myopia. • The effect of EA ...at Hegu and Taiyang acupoints shows a positional specificity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Polypropylene (PP) is incorporated with four different grades (H100, M25, M5, and C300) of graphene nanoplatelets (GnPs) via twin screw extrusion followed by injection moulding. The composites' ...thermal stability, crystallization behaviour, tensile strength, and electrical property are carefully examined. The thermal stability is significantly enhanced with the incorporation of small-sized GnPs as shown by the 11.2% improvement in T5% (the temperature at which 5 wt% of the mass loss occurs) and 5.1% improvement in Tmax (the temperature at which the maximum loss rate occurs). The thermal stabilizing effect of fillers can be significantly enhanced when they are well distributed with less aggregation as is the case for small-sized GnPs. The GnPs show a considerable nucleating effect on PP by increasing the crystallization temperature (Tc). The greatest improvement in tensile property is achieved with the use of small-sized GnPs. A 33.0% enhancement in tensile strength and 59.1% improvement of tensile modulus are obtained with the use of C300 and M5, respectively. The significantly increased thermal stability and mechanical property with small-sized GnPs are due to the fact that these smallsized fillers achieve a high degree of dispersion with less agglomeration as shown in the scanning electron microscope (SEM) images. However, the fillers with a large sheet size are still beneficial for purposes concerning electrical conductivity since the lowest percolation is obtained with H100. The greater the size of the GnPs, the smaller the percolation threshold of composites is exhibited.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This paper presents the results of a recent study conducted to refine the design-oriented stress–strain model originally proposed by Lam and Teng for fiber-reinforced polymer (FRP)-confined concrete ...under axial compression. More accurate expressions for the ultimate axial strain and the compressive strength are proposed for use in this model. These new expressions are based on results from recent tests conducted by the writers’ group under well-defined conditions and on results from a parametric study using an accurate analysis-oriented stress–strain model for FRP-confined concrete. They allow the effects of confinement stiffness and the jacket strain capacity to be separately reflected and accounts for the effect of confinement stiffness explicitly instead of having it reflected only through the confinement ratio. The new expressions can be easily incorporated into Lam and Teng’s model for more accurate predictions. Based on these new expressions, two modified versions of Lam and Teng’s model are presented. The first version involves only the updating of the ultimate axial strain and compressive strength equations. The second version caters to stress–strain curves with a descending branch, which is not covered by the original model.
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FGGLJ, IZUM, KILJ, NUK, PILJ, SAZU, UL, UM, UPUK
Lanthanide-doped upconversion nanoparticles have attracted extensive research interest due to their promising applications in various fields. However, conventional upconversion nanoparticles ...generally suffer from severe quenching effect, leading to extremely weak luminescence that greatly hinders their practical use. To date, great efforts have been made for boosting the upconversion luminescence of these functional nanoparticles through numerous approaches, which can be fundamentally divided into two categories including chemical methods and physical strategies. In this review, a comprehensive survey on the existing approaches for realizing highly enhanced upconversion luminescence is provided. As for the typical chemical methods, chemical composition tuning including suitable selection of host and heavy lanthanide doping, core-shell engineering, ligand modification, dye sensitization, impurity doping and ion exchange are summarized. With respect to the emerging physical strategies, laser excitation modulation that includes the tuning of power density and polarization angle, near-field regulation that involves the exertion of plasmon, photonic crystal and dielectric superlens, heat-associated annealing and inverse thermal quenching as well as the application of external field stimuli like electric field, magnetic field and pressure are overviewed. Current challenges and future opportunities associated with lanthanide-doped upconversion nanoparticles are also discussed in the end.
Lanthanide-doped upconversion nanoparticles have attracted extensive research interest due to their promising applications in various fields.
Estimates of 21st Century global-mean surface temperature increase have generally been based on scenarios that do not include climate policies. Newly developed multigas mitigation scenarios, based on ...a wide range of modeling approaches and socioeconomic assumptions, now allow the assessment of possible impacts of climate policies on projected warming ranges. This article assesses the atmospheric CO₂ concentrations, radiative forcing, and temperature increase for these new scenarios using two reduced-complexity climate models. These scenarios result in temperature increase of 0.5-4.4°C over 1990 levels or 0.3-3.4°C less than the no-policy cases. The range results from differences in the assumed stringency of climate policy and uncertainty in our understanding of the climate system. Notably, an average minimum warming of ≈1.4°C (with a full range of 0.5-2.8°C) remains for even the most stringent stabilization scenarios analyzed here. This value is substantially above previously estimated committed warming based on climate system inertia alone. The results show that, although ambitious mitigation efforts can significantly reduce global warming, adaptation measures will be needed in addition to mitigation to reduce the impact of the residual warming.
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Abstract
The dramatic changes in the magnetic field at the dipolarization front (DF) provide a suitable environment for electron acceleration, which usually can cause the flux enhancement of ...energetic electrons behind the front. However, it is unknown whether energetic electrons observed at the DF are energized locally, and which mechanism accelerates the electrons at the DF is unclear. Our study performs a direct quantitative analysis to reveal the acceleration process of energetic electrons at the DF using the high-time-resolution data from NASA's Magnetospheric Multiscale mission. The fluxes of energetic electrons at 90° are enhanced at the front. Under adiabatic conditions, our quantitative analysis indicates that these electrons at the front could be locally accelerated to over 100 keV by betatron acceleration. Eventually, the electron temperature anisotropy formed via the betatron mechanism could provide the free energy to excite whistler waves at the DF. Our quantitative study provides, for the first time, strong direct evidence for the local electron acceleration at the DF.
Uncertainty surrounds the effects of cerebral edema on outcomes in intracerebral hemorrhage (ICH).
We used data from the INTERACT trial to determine the predictors and prognostic significance of ..."perihematomal" edema over 72 hours after ICH. INTERACT included 404 patients with CT-confirmed ICH and elevated systolic blood pressure (BP) (150-220 mm Hg) who had the capacity to commence BP lowering treatment within 6 hours of ICH. Baseline and repeat CT (24 and 72 hours) were performed using standardized techniques, with digital images analyzed centrally. Predictors of growth in edema were determined using generalized estimating equations, and its effects on clinical outcomes were estimated using a logistic regression model.
Overall, 270 patients had 3 sequential CT scans available for analyses. At baseline, there was a highly significant correlation between hematoma and perihematomal edema volumes (r(2) = 0.45). Lower systolic BP and baseline hematoma volume were independently associated with absolute increase in perihematomal edema volume. History of hypertension, baseline hematoma volume, and earlier time from onset to CT were independently associated with relative increase in edema volume. Both absolute and relative increases in perihematomal edema growth were significantly associated with death or dependency at 90 days after adjustment for age, gender, and randomized treatment, but not when additionally adjusted for baseline hematoma volume.
The degree of, and growth in, perihematomal edema are strongly related to the size of the underlying hematoma of acute intracerebral hemorrhage, and do not appear to have a major independent effect in determining the outcome from this condition.
•Protein corona formation was related to the surface properties of PSNPs.•BSA significantly improved the stability of PS-Bare and PS-COOH in electrolytes.•Protein corona structure was visualized by ...negative-stained TEM.•Anion displayed contrary effects on the stability of oppositely charged PSNPs.•PSNPs would suspend in fresh water for a long time due to NOM corona formation.
Nanosized plastics are considered as being a class of contaminants of emerging concern. The interaction between nanoplastics and proteins may significantly influence the environmental behavior and fate of nanoplastics. Here, we employed time-resolved dynamic light scattering to explore the aggregation kinetics and stability of polystyrene nanoparticles (PSNPs) exposed to a model globular protein (bovine serum albumin, BSA) in the presence of a number of typical electrolytes (NaCl, CaCl2, and Na2SO4). With the increase of the BSA concentration, the amount of BSA adsorbed on the surface of negatively charged PS-Bare (non-modified) and PS-COOH (carboxyl-modified) increased, resulting in higher dispersibility in comparison to the treatment without BSA. This stabilization effect derived from the protein corona structure was revealed by combining characterization techniques and visualized by transmission electron microscopy. Upon addition of NaCl and CaCl2, the aggregation of positively charged PS-NH2 (amino-modified) was inhibited by the BSA addition possibly due to the screening of the attractive patch-charge force and the competition for adsorption of cations between PS-NH2 and the protein. When Na2SO4 was present in the suspension, BSA addition significantly increased PS-NH2 aggregation rate due to patch-charge attraction and the high performance of SO42− in attaching to particles and charge neutralization. These findings shed light on the interactions between PSNPs and proteins, which were shown to vary with the composition of the surface coatings of PSNPs. The newly gained knowledge will help us to forecast the transport and fate of PSNPs in natural aqueous systems.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Dominant mutations in sarcomere proteins such as the myosin heavy chains (MHC) are the leading genetic causes of human hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy. We found that ...expression of the HCM-causing cardiac MHC gene (Myh6) R403Q mutation in mice can be selectively silenced by an RNA interference (RNAi) cassette delivered by an adeno-associated virus vector. RNAi-transduced MHC⁴⁰³ / ⁺ mice developed neither hypertrophy nor myocardial fibrosis, the pathologic manifestations of HCM, for at least 6 months. Because inhibition of HCM was achieved by only a 25% reduction in the levels of the mutant transcripts, we suggest that the variable clinical phenotype in HCM patients reflects allele-specific expression and that partial silencing of mutant transcripts may have therapeutic benefit.
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