157 research outputs found
A comparison of pitting susceptibility of Q235 and HRB335 carbon steels used for reinforced concrete
The phase structure and the pitting susceptibility of two carbon steels, Q235 and HRB335, used for reinforced concrete, are investigated by phase observation, polarization curve measure-ments, electrochemical impedance spectroscopy, and Mott-Schottky analysis. It is found that Q235 is ferrite and HRB335 is pearlite. Q235 is more susceptible to chloride ions leading to pit-ting than HRB335. The polarization curves show that the breakdown potential of the passive film in saturated Ca(OH)2 solution containing 0.4 M NaCl is 0 V for Q235 and 0.34 V for HRB335. The Mott-Schottky analyses show that passive films formed on Q235 and HRB335 in saturated Ca(OH)2 solution containing chloride ions behave like an n-type semiconductor. The passive film formed on Q235 has a higher donor density, which explains why Q235 is more susceptible to pitting than HRB335
Wetland mapping in the Balqash Lake Basin Using Multi-source Remote Sensing Data and Topographic features Synergic Retrieval
AbstractWetland plays a major role in the hydrological cycle, the carbon sink (carbon sequestration), nitrogen absorption, geochemical cycle, water conservation, biological diversity. Traditional field surveys for mapping wetlands distribution in large areas are very difficult to undertake. Remote sensing techniques offer promising solutions to this problem. But spectral confusion with other land cover classes and different types of wetlands, it is difficult to extract wetland information automatically. The overarching goal of this study was to develop a hybrid method for lake wetlands automated delineation by integrated using multi-source remote sensing data and DEM data. Firstly, it is to do radiance correction and convert image DN value to reflectance or radiance. Secondly, spectral index calculation and topographic indices derive, such as NDVI, NDWI, TVDI, slope and others topographic feature indices and etc. Thirdly, water bodies extraction through the NDWI iterative computation. Finally, it is to retrieve marsh land from image via comprehensive information of soil moisture character, topographic factors and spatial analysis. By the above steps, we got the ultimate wetlands distribution information. The methodology was evaluated by the balqash lake basin wetland extraction in Kazakhstan. Experiments result shows that the hybrid method performs well in lake wetlands delineation. The overall accuracies of wetland classes exceed 85%, which can meet the application requirements
LSSANet: A Long Short Slice-Aware Network for Pulmonary Nodule Detection
Convolutional neural networks (CNNs) have been demonstrated to be highly
effective in the field of pulmonary nodule detection. However, existing CNN
based pulmonary nodule detection methods lack the ability to capture long-range
dependencies, which is vital for global information extraction. In computer
vision tasks, non-local operations have been widely utilized, but the
computational cost could be very high for 3D computed tomography (CT) images.
To address this issue, we propose a long short slice-aware network (LSSANet)
for the detection of pulmonary nodules. In particular, we develop a new
non-local mechanism termed long short slice grouping (LSSG), which splits the
compact non-local embeddings into a short-distance slice grouped one and a
long-distance slice grouped counterpart. This not only reduces the
computational burden, but also keeps long-range dependencies among any elements
across slices and in the whole feature map. The proposed LSSG is easy-to-use
and can be plugged into many pulmonary nodule detection networks. To verify the
performance of LSSANet, we compare with several recently proposed and
competitive detection approaches based on 2D/3D CNN. Promising evaluation
results on the large-scale PN9 dataset demonstrate the effectiveness of our
method. Code is at https://github.com/Ruixxxx/LSSANet.Comment: MICCAI 202
Self-assembly of polyoxometalate-peptide hybrids in solution: elucidating the contributions of multiple possible driving forces
Incorporating the building blocks of nature (e.g., peptides and DNA) into inorganic polyoxometalate (POM) clusters is a promising approach to improve the compatibilities of POMs in biological fields. To extend their biological applications, it is necessary to understand the importance of different nonâcovalent interactions during selfâorganization. A series of Anderson POMâpeptide hybrids have been used as a simple model to demonstrate the role of different interactions in POMâpeptide (biomolecules) systems. Regardless of peptide chain length, these hybrids follow similar solution behaviors, forming hollow, spherical supramolecular structures in acetonitrile/water mixed solvents. The incorporation of peptide tails introduces interesting stimuliâresponsive properties to temperature, hybrid concentration, solvent polarity and ionic strength. Unlike the typical bilayer amphiphilic vesicles, they are found to follow the blackberryâtype assemblies of hydrophilic macroions, which are regulated by electrostatic interaction and hydrogen bonding. The formation of electrostatic assemblies before the supramolecular formation is confirmed by ionâmobility mass spectrometry (IMSâMS)
Association between serum Klotho concentration and hyperlipidemia in adults: a cross-sectional study from NHANES 2007â2016
ObjectiveThe Klotho protein is a well-documented anti-aging protein known for its diverse biological functions. Hyperlipidemia is an established independent risk factor for various chronic diseases. However, there is limited understanding of the connection between Klotho and hyperlipidemia. The aim was to assess the association between serum Klotho levels and hyperlipidemia among adults.MethodsThe study included 11,618 individuals from the NHANES database from 2006 to 2017. Hyperlipidemia was diagnosed following the National Cholesterol Education Program guidelines. Serum Klotho concentration was measured by an enzyme-linked immunosorbent assay kit, and the association between Klotho and hyperlipidemia was assessed by a multivariable logistic regression model. Fitted smoothing curves and threshold-effect analysis were employed to describe nonlinear relationships.ResultsIn our multiple logistic regression models, serum Klotho concentration was significantly associated with hyperlipidemia after adjusting for comprehensive confounders (per SD increment odds ratio (OR): 0.91; 95% confidence interval (CI): 0.86â0.97). Compared to individuals in the lowest Klotho quartile, those in the highest quartile exhibited a substantially decreased prevalence of hyperlipidemia (OR: 0.72; 95% CI: 0.58â0.90). Using a two-segment logistic regression model, we identified a U-shaped relationship between serum Klotho concentration and hyperlipidemia, with an inflection point at 1,365.5 pg/mL. Subgroup analysis did not reveal any potential moderating effects.ConclusionThis study revealed an inverse relationship between Klotho levels and hyperlipidemia. Further investigation is warranted to explore the underlying mechanism between serum Klotho and hyperlipidemia
Causal relationship between atrial fibrillation and cognitive impairment: a Mendelian randomization study
Objective¡To investigate the causal relationship between atrial
fibrillation (AF) and cognitive impairment.Methods¡A two-sample Mendelian randomization (TSMR)
analysis was used to assess the potential causality of AF on cognitive dysfunction. Single
nucleotide polymorphisms (SNPs) strongly associated with AF were extracted as instrumental
variables by using a dataset of a large-scale genome-wide association study (GWAS) on AF. The
associations of SNPs with Alzheimerâ˛s disease dementia, Parkinsonâ˛s disease dementia, vascular
dementia, Lewy body dementia, frontotemporal dementia, undefined dementia, and overall
cognitive function assessment were extracted separately from publicly available GWAS data on
cognitive dysfunction. The inverse variance-weighted (IVW) method was used for the main
analysis, and sensitivity analyses were conducted by using Cochranâ˛s Q test, MR-Egger
regression, and leave-one-out method. To verify the robustness of the results, replicate
analyses and meta-analyses were performed by using different GWAS data.Results¡In the initial
analysis, 101 SNPs were extracted as instrumental variables from a meta-analysis of a
genome-wide association study involving up to 1 030 836 individuals. The IVW analysis showed
no evidence for causal associations between AF and dementia [dementia (OR=1.032; 95%CI
0.973â1.094; P=0.290), Parkinsonâ˛s disease dementia (OR=1.004; 95%CI 0.780â1.291; P=0.977),
vascular dementia (OR=1.123; 95%CI 0.969â1.301; P=0.125), or unspecified dementia (OR=1.013;
95%CI 0.910â1.129; P=0.807)]. In the replication analysis, 27 SNPs were extracted as
instrumental variables from the FinnGen AF GWAS data, and the IVW analysis were consistent
with the initial analysis [cognitive function (OR=0.999; 95%CI 0.982â1.016; P=0.874),
Alzheimerâ˛s disease dementia (OR=0.977; 95%CI 0.943â1.012; P=0.193), Lewy body dementia
(OR=1.014; 95%CI 0.898â1.145; P=0.826), or frontotemporal dementia (OR=0.996; 95%CI
0.745â1.333; P=0.980)]. Both Mendelian randomization analyses and meta-analyses showed no
evidence of an association between genetically predicted AF and different types of dementia or
overall cognitive function assessment. MR-Egger regression suggested no horizontal pleiotropy
and leave-one-out analysis showed stable results after individually removing each
SNP.Conclusion¡No evidence of a causal relationship between AF and cognitive impairment was
found. The associations observed in observational studies can be partially attributed to
confounding factors such as shared biology or co-morbidities
Concept for a Future Super Proton-Proton Collider
Following the discovery of the Higgs boson at LHC, new large colliders are
being studied by the international high-energy community to explore Higgs
physics in detail and new physics beyond the Standard Model. In China, a
two-stage circular collider project CEPC-SPPC is proposed, with the first stage
CEPC (Circular Electron Positron Collier, a so-called Higgs factory) focused on
Higgs physics, and the second stage SPPC (Super Proton-Proton Collider) focused
on new physics beyond the Standard Model. This paper discusses this second
stage.Comment: 34 pages, 8 figures, 5 table
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