Two-dimensional transition metal carbides, that is, MXenes and especially Ti3C2, attract attention due to their excellent combination of properties. Ti3C2 nanosheets could be the material of choice ...for future flexible electronics, energy storage, and electromechanical nanodevices. There has been limited information available on the mechanical properties of Ti3C2, which is essential for their utilization. We have fabricated Ti3C2 nanosheets and studied their mechanical properties using direct in situ tensile tests inside a transmission electron microscope, quantitative nanomechanical mapping, and theoretical calculations employing machine-learning derived potentials. Young’s modulus in the direction perpendicular to the Ti3C2 basal plane was found to be 80–100 GPa. The tensile strength of Ti3C2 nanosheets reached up to 670 MPa for ∼40 nm thin nanoflakes, while a strong dependence of tensile strength on nanosheet thickness was demonstrated. Theoretical calculations allowed us to study mechanical characteristics of Ti3C2 as a function of nanosheet geometrical parameters and structural defect concentration.
An agricultural ammonia (NH
3) emission inventory in the North China Plain (NCP) on a prefecture level for the year 2004, and a 5 × 5 km
2 resolution spatial distribution map, has been calculated for ...the first time. The census database from China's statistics datasets, and emission factors re-calculated by the RAINS model supported total emissions of 3071 kt NH
3–N yr
−1 for the NCP, accounting for 27% of the total emissions in China. NH
3 emission from mineral fertilizer application contributed 1620 kt NH
3–N yr
−1, 54% of the total emission, while livestock emissions accounted for the remaining 46% of the total emissions, including 7%, 27%, 7% and 5% from cattle, pigs, sheep and goats, and poultry, respectively. A high-resolution spatial NH
3 emissions map was developed based on 1 × 1 km land use database and aggregated to a 5 × 5 km grid resolution. The highest emission density value was 198 kg N ha
−1 yr
−1.
The first high-resolution spatial distribution of ammonia emissions for the North China Plain showed rates up to 200 kg NH
3–N ha
−1 yr
−1.
► Sodium borate decreases the electrical conductivity of an alkaline solution. ► Sodium borate can cause intensive spark discharge on sample surface during MAO. ► The boron content of anodic coatings ...is within the range of 0.84–5.10at.%. ► The coatings formed in solutions containing sodium borate consist of Mg3B2O6.
The influence of sodium borate concentration on the formation and properties of anodic coatings obtained by micro arc oxidation (MAO) on magnesium alloys was systematically studied in an alkaline solution with addition of 0–40g/L sodium borate. It is shown that sodium borate can decrease the solution conductivity, take part in the coating formation and increase the coating thickness. With the increase of sodium borate concentration, the boron content in the coatings increases in the range of 10–20g/L but decreases within the range of 20–40g/L. Sodium borate cannot further improve the corrosion resistance attributed to the development of porous or rough anodic coatings.
Summary
We performed a GWAS of trochanter and intertrochanter bone mineral density (BMD) in the Framingham Heart Study and replicated in three independent studies. Our results identified one novel ...locus around the associated variations at chromosomal region 3q13.32 and replicated two loci at chromosomal regions 3p21 and 8q24. Our findings provide useful insights that enhance our understanding of bone development, osteoporosis, and fracture pathogenesis.
Introduction
Hip trochanter (TRO) and intertrochanter (INT) subregions have important clinical relevance to subtrochanteric and intertrochanteric fractures but have rarely been studied by genome-wide association studies (GWASs).
Methods
Aiming to identify genomic loci associated with BMD variation at TRO and INT regions, we performed a GWAS utilizing the Framingham Heart Study (FHS,
N
= 6,912) as discovery sample and utilized the Women’s Health Initiative (WHI) African-American subsample (
N
= 845), WHI Hispanic subsample (
N
= 446), and Omaha osteoporosis study (
N
= 971), for replication.
Results
Combining the evidence from both the discovery and the replication samples, we identified one novel locus around the associated variations at chromosomal region 3q13.32 (
rs1949542
, discovery
p
= 6.16 × 10
−8
, replication
p
= 2.86 × 10
−4
for INT-BMD; discovery
p
= 1.35 × 10
−7
, replication
p
= 4.16 × 10
−4
for TRO-BMD, closest gene
RP11-384F7.1
). We also replicated two loci at chromosomal regions 3p21 (
rs148725943
, discovery
p
= 6.61 × 10
−7
, replication
p
= 5.22 × 10
−4
for TRO-BMD, closest gene
CTNNB1
) and 8q24 (
rs7839059
, discovery
p
= 2.28 × 10
−7
, replication
p
= 1.55 × 10
−3
for TRO-BMD, closest gene
TNFRSF11B
) that were reported previously. We demonstrated that the effects at both 3q13.32 and 3p21 were specific to the TRO, but not to the femoral neck and spine. In contrast, the effect at 8q24 was common to all the sites.
Conclusion
Our findings provide useful insights that enhance our understanding of bone development, osteoporosis, and fracture pathogenesis.
Highlights • Sevoflurane-induced neuronal apoptosis could be attenuated by mGluR7 activator LAP4 or AMN082. • β-Arr2-dependent Phospho-ERK1/2 reduces sevoflurane neurotoxicity by inhibiting ...Phospho-Bad. • β-Arr1 modulates mGluR7 signaling by interacting with CBP and p300 in sevoflurane neurotoxicity. • LAP4 or AMN082 improves postnatal sevoflurane-induced emotional and spatial cognitive deficits.
We report results on the searches of weakly interacting massive particles (WIMPs) with sub-GeV masses (mχ) via WIMP-nucleus spin-independent scattering with Migdal effect incorporated. Analysis on ...time-integrated (TI) and annual modulation (AM) effects on CDEX-1B data are performed, with 737.1 kg day exposure and 160 eVee threshold for TI analysis, and 1107.5 kg day exposure and 250 eVee threshold for AM analysis. The sensitive windows in mχ are expanded by an order of magnitude to lower DM masses with Migdal effect incorporated. New limits on σχNSI at 90% confidence level are derived as 2×10−32∼7×10−35 cm2 for TI analysis at mχ∼50–180 MeV/c2, and 3×10−32∼9×10−38 cm2 for AM analysis at mχ∼75 MeV/c2–3.0 GeV/c2.
Many studies bias correct daily precipitation from climate models to match the observed precipitation statistics, and the bias corrected data are then used for various modelling applications. This ...paper presents a review of recent methods used to bias correct precipitation from regional climate models (RCMs). The paper then assesses four bias correction methods applied to the weather research and forecasting (WRF) model simulated precipitation, and the follow-on impact on modelled runoff for eight catchments in southeast Australia. Overall, the best results are produced by either quantile mapping or a newly proposed two-state gamma distribution mapping method. However, the differences between the methods are small in the modelling experiments here (and as reported in the literature), mainly due to the substantial corrections required and inconsistent errors over time (non-stationarity). The errors in bias corrected precipitation are typically amplified in modelled runoff. The tested methods cannot overcome limitations of the RCM in simulating precipitation sequence, which affects runoff generation. Results further show that whereas bias correction does not seem to alter change signals in precipitation means, it can introduce additional uncertainty to change signals in high precipitation amounts and, consequently, in runoff. Future climate change impact studies need to take this into account when deciding whether to use raw or bias corrected RCM results. Nevertheless, RCMs will continue to improve and will become increasingly useful for hydrological applications as the bias in RCM simulations reduces.
The effect of N form (NO₃ ⁻ versus NH₄ ⁺) on growth and uptake of Cd and Zn by the hyperaccumulator Thlaspi caerulescens (Ganges ecotype) was investigated in hydroponic and rhizobox experiments. In ...the hydroponic experiments, NO₃ ⁻ or NH₄ ⁺ was supplied to plants with the pH of the nutrient solution being unbuffered or buffered at around 6.0. A moderately contaminated soil was used in the rhizobox experiment with or without additions of NO₃ ⁻, NH₄ ⁺ or NH₄ ⁺ + DCD (dicyanodiamide, a nitrification inhibitor). A higher biomass was obtained when N was supplied as NO₃ ⁻ in both experiments, indicating that T. caerulescens prefers NO₃ ⁻ over NH₄ ⁺. In the hydroponic experiments, supplying NO₃ ⁻ resulted in a doubling of Cd concentration in the shoots compared with the NH₄ ⁺ treatment, regardless whether solution pH was buffered or not. The form of N also had a noticeable effect on root Zn concentrations. In the rhizosphere box experiment, rhizosphere pH was markedly influenced by the N treatment. The acidification in the NH₄ ⁺ and NH₄ ⁺ + DCD treatments increased the concentrations of extractable Cd and Zn, both of which showed a considerable depletion in the rhizosphere. However, total uptake of Cd and Zn were highest in the NO₃ ⁻ treatment, despite the fact that concentrations of extractable Cd and Zn in the rhizosphere were the lowest in this treatment. The results showed that supplying N as NO₃ ⁻ promoted growth and phytoextraction of Cd and Zn by T. caerulescens compared with NH₄ ⁺.
In this work, a rare earth (RE) free Mg69Zn27Ca4 bulk metallic glass (BMG) of diameter 1.5mm was successfully fabricated by the injection casting method using recycled materials in atmospheric air. ...Without using high vacuum conditions, high purity starting materials and expensive rare earth materials, the findings of the work are of significance in reducing the cost and improving the manufacturability of BMGs. The results of the uniaxial compression tests further showed that there were no obvious differences between BMGs prepared under high vacuum or in atmospheric environment. The electrochemical polarization measurements in simulated physiological media revealed that the atmospheric Mg69Zn27Ca4 BMG manifested much lower passive current densities, higher pitting potential and a wider passive region than those of ZK60 and pure Mg alloys. The findings not only present Mg69Zn27Ca4 BMG as low cost material for potential biomedical applications, but also provide new insights into understanding of the effects of oxygen on glass formation.
•A Mg69Zn27Ca4 bulk metallic glass was successfully prepared in atmospheric air.•This glassy alloy can be fabricated using recycled materials in atmospheric air.•This glassy alloy possesses high fracture strength and good corrosion resistance.•The findings are significant as a means of reducing the cost and manufacturability.
Anodic coatings were prepared by microarc oxidation (MAO) on AZ91HP in a base solution of 10
g/L NaOH with and without the addition of 0–12
g/L phytic acid (C
6H
18O
24P
6). The influences of C
6H
...18O
24P
6 and its concentration on the conductivity and breakdown voltage were studied. The morphologies and compositions of anodic coatings were determined by environmental scanning electron microscope (ESEM) and energy dispersive X-ray spectroscopy (EDX). Potentiodynamic polarization test was performed in 3.5
wt.% NaCl solution to evaluate the corrosion resistance of anodic coatings. The results showed that with the increase of C
6H
18O
24P
6 concentration, the solution conductivity decreased while the values of breakdown voltage increased. EDX analysis showed that the coatings formed in solutions with C
6H
18O
24P
6 addition contained Mg, Al, O, C, P and a trance of Na. The addition of C
6H
18O
24P
6 into the base solution was helpful in coating formation and the coatings formed in the solution containing 8
g/L C
6H
18O
24P
6 exhibited the best pore uniformity and corrosion resistance.
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