In this work, a new composite materials of graphene oxide (GO)-incorporated metal-organic framework (MOF)(UiO-66-NH₂/GO) were in-situ synthesized, and were found to exhibit enhanced high performances ...for CO₂ capture. X-ray diffraction (XRD), scanning electron microscope (SEM), N₂ physical adsorption, and thermogravimetric analysis (TGA) were applied to investigate the crystalline structure, pore structure, thermal stability, and the exterior morphology of the composite. We aimed to investigate the influence of the introduction of GO on the stability of the crystal skeleton and pore structure. Water, acid, and alkali resistances were tested for physical and chemical properties of the new composites. CO₂ adsorption isotherms of UiO-66, UiO-66-NH₂, UiO-66/GO, and UiO-66-NH₂/GO were measured at 273 K, 298 K, and 318 K. The composite UiO-66-NH₂/GO exhibited better optimized CO₂ uptake of 6.41 mmol/g at 273 K, which was 5.1% higher than that of UiO-66/GO (6.10 mmol/g). CO₂ adsorption heat and CO₂/N₂ selectivity were then calculated to further evaluate the CO₂ adsorption performance. The results indicated that UiO-66-NH₂/GO composites have a potential application in CO₂ capture technologies to alleviate the increase in temperature of the earth's atmosphere.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•The epidemic dynamics of COVID-19 by age and gender groups in South Korea are different.•The epidemic process of COVID-19 was driven by young people aged 20–39, with two peaks from February 19 to ...May 2, 2020.•The epidemic among elderly people declined steadily after March 15, 2020, despite large fluctuations in daily new cases among young people.•Elderly people can be effectively protected during the COVID-19 pandemic.
Elderly people had suffered a disproportionate burden of COVID-19. We hypothesized that males and females in different age groups might have different epidemic trajectories.
Using publicly available data from South Korea, daily new COVID-19 cases were assessed using generalized additive models, assuming Poisson and negative binomial distributions. Epidemic dynamics by age and gender groups were explored using interactions between smoothed time terms and age and gender.
A negative binomial distribution fitted the daily case counts best. The relationship between the dynamic patterns of daily new cases and age groups was statistically significant (p<0.001), but this was not the case with gender groups. People aged 20–39 years led the epidemic processes in South Korean society with two peaks — one major peak around March 1 and a smaller peak around April 7, 2020. The epidemic process among people aged 60 or above trailed behind that of the younger age group, and with smaller magnitude. After March 15, there was a consistent decline of daily new cases among elderly people, despite large fluctuations in case counts among young adults.
Although young people drove the COVID-19 epidemic throughout society, with multiple rebounds, elderly people could still be protected from infection after the peak of the epidemic.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Accurate prediction of aviation safety levels is significant for the efficient early warning and prevention of incidents. However, the causal mechanism and temporal character of aviation accidents ...are complex and not fully understood, which increases the operation cost of accurate aviation safety prediction. This paper adopts an innovative statistical method involving a least absolute shrinkage and selection operator (LASSO) and long short-term memory (LSTM). We compiled and calculated 138 monthly aviation insecure events collected from the Aviation Safety Reporting System (ASRS) and took minor accidents as the predictor. Firstly, this paper introduced the group variables and the weight matrix into LASSO to realize the adaptive variable selection. Furthermore, it took the selected variable into multistep stacked LSTM (MSSLSTM) to predict the monthly accidents in 2020. Finally, the proposed method was compared with multiple existing variable selection and prediction methods. The results demonstrate that the RMSE (root mean square error) of the MSSLSTM is reduced by 41.98%, compared with the original model; on the other hand, the key variable selected by the adaptive spare group lasso (ADSGL) can reduce the elapsed time by 42.67% (13 s). This shows that aviation safety prediction based on ADSGL and MSSLSTM can improve the prediction efficiency of the model while keeping excellent generalization ability and robustness.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background
Locally advanced rectal cancer (LARC) patient stratification by clinicoradiologic factors may yield variable results. Therefore, more efficient prognostic biomarkers are needed for ...improved risk stratification of LARC patients, personalized treatment, and prognostication.
Purpose/Hypothesis
To compare the ability of a radiomic signature to predict disease‐free survival (DFS) with that of a clinicoradiologic risk model in individual patients with LARC.
Study Type
Retrospective study.
Population
In all, 108 consecutive patients (allocated to a training and validation set with a 1:1 ratio) with LARC treated with neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision (TME).
Field Strength/Sequence
Axial 3D LAVA multienhanced MR sequence at 3T.
Assessment
ITK‐SNAP software was used for manual segmentation of 3D pre‐nCRT MR images. All manual tumor segmentations were performed by a gastrointestinal tract radiologist, and validated by a senior radiologist. The clinicoradiologic risk factors with potential prognostic outcomes were identified in univariate analysis based on the Cox regression model for the whole set. The results showed that ypT, ypN, EMVI, and MRF were potential clinicoradiologic risk factors. Interestingly, only ypN and MRF were identified as independent predictors in multivariate analysis based on the Cox regression model.
Statistical Tests
A radiomic signature based on 485 3D features was generated using the least absolute shrinkage and selection operator (LASSO) Cox regression model. The association of the radiomic signature with DFS was investigated by Kaplan–Meier survival curves. Survival curves were compared by the log‐rank test. Three models were built and assessed for their predictive values, using the Harrell concordance index and integrated time‐dependent area under the curve.
Results
The novel radiomic signature stratified patients into low‐ and high‐risk groups for DFS in the training set (hazard ratio HR = 6.83; P < 0.001), and was successfully validated in the validation set (HR = 2.92; P < 0.001). The model combining the radiomic signature and clinicoradiologic findings had the best performance (C index = 0.788, 95% confidence interval CI 0.72–0.86; integrated time‐dependent area under the curve of 0.837 at 3 years).
Data Conclusion
The novel radiomic signature could be used to predict DFS in patients with LARC. Furthermore, combining this radiomic signature with clinicoradiologic features significantly improved the ability to estimate DFS (P = 0.001, 0.005 in training set and in validation set, respectively), and may help guide individualized treatment in such patients.
Level of Evidence: 3
Technical Efficacy: Stage 5
J. Magn. Reson. Imaging 2018;48:605–614.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The pathogenic bacterium
Pectobacterium carotovorum
causes soft rot in cabbage and significantly reduces plant yield. In this study, we employed
Mhonia fortunei
extracts to synthesis silver ...nanoparticles (Mf-AgNPs) and investigated their functions against
P. carotovorum
. The results showed that the surface plasmon resonance (SPR) peak of AgNP was 412 nm under optimal synthesis conditions. Furthermore, the results of Scanning electron microscope-Energy dispersive spectrometer (SEM-EDS) and High-resolution transmission electron microscopy (HR-TEM) revealed that the Mf-AgNPs had a spherical structure with an average diameter of 13.19 nm and the content of Ag0 ions accounted for 82.68% of the total elemental content. The X-Ray diffraction (XRD) results confirmed that AgNPs had a face-centered cubic (FCC) crystal structure, while Fourier transform infrared spectroscopy (FTIR) results indicated the presence of various biomolecules as reducing and stabilizing agents on the AgNP surface. Antibacterial activity was first evaluated by an inhibitory zone test, which revealed that 500 μg ml
−1
of AgNPs had antibacterial activity against
P. carotovorum
and four model bacteria including
Staphylococcus aureus
,
Escherichia coli
,
Bacillus subtilis
, and
Pseudomonas aeruginosa
, respectively with an antibacterial function comparable to 1 mM AgNO
3
solution. The Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for
P. carotovorum
were 8 μg ml
−1
, respectively. Furthermore, AgNPs at 8 μg ml
−1
completely inhibited the growth of
P. carotovorum
, decreased their tolerance to 0.25 mM H
2
O
2
as well as considerably reduced colony formation after 1 h of treatment and thereafter. Treatment with Mf-AgNPs resulted in bacterial cell membrane destruction and biofilm formation inhibition, respectively. With an FIC (fractional inhibitory concentration) index of 0.174, AgNP and zhongshengmycin showed a significant synergistic effect. The infection of
P. carotovorum
to cabbage explants was significantly inhibited
in vitro
by a combination of 2 μg ml
−1
Mf-AgNP and 5 μg ml
−1
zhongshengmycin. In conclusion, the synthesized Mf-AgNP exhibited significant antibacterial activity against
P. carotovorum
.
•A new modified flag-shape (MFS) model and its equivalent linearization interpretation is proposed.•The effectiveness of the MFS model and the corresponding equivalent linearization coefficients is ...verified.•Optimization using the MFS model subject to stochastic excitation demonstrate more economic ductility demand in structural design.
The analysis and design of self-centering structural systems have attracted substantial attention from researchers for the seismic design of structures. The flag-shaped hysteretic model has been widely used in the design and structural response analysis of self-centering devices. In this research, a modified flag-shaped (MFS) model is proposed to describe the hysteretic characteristics of self-centering energy dissipation (SCED) braces, which are commonly used in self-centering structures. The MFS model comprises three parts: a linear elastic part, a bilinear elastic part, and an elasto-plastic part with a slip zone. The effectiveness of the MFS model is validated based on the results of the quasi-static and hybrid simulation tests available in the literature. Equivalent linearization is carried out on the MFS model for stochastic earthquakes, and closed-form solutions are obtained for the linearized parameters. A one-degree-of-freedom braced system is used to verify the equivalent linearization of the MFS model in comparison with Monte Carlo simulation results. Finally, an SCED-braced five-story frame structure is optimized by minimizing the maximum ductility demand for the SCED braces using the equivalent linearization of the MFS model. The optimized design by the MFS model is observed to exhibit uniform ductility demands along the height. This can be considered as the ideal optimal solution. The responses of the multi-degree-of-freedom structure also demonstrate the effectiveness of the proposed MFS model and its equivalent linearization.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A numerical simulation model has been developed, and was consistent well with the experimental results.•The strength, modulus and energy absorption capacity of the Pyramidal Kagome lattice material ...were proportional to the square of its relative density.•The strain rate hardening effect of the base material plays a major role for the rate sensitivity of the Pyramidal Kagome lattice material.•Increasing the number of lateral units and reducing the number of layers contributed to the improvement on the mechanical properties of the Pyramidal Kagome lattice material.
The present study aimed at understanding the influences of structural parameters on the mechanical properties of Pyramidal Kagome (PK) lattice material under impact loading. Seven different PK structures varying height-width ratio and rod diameter were manufactured by selective laser melting (SLM). In this study, both experiments and simulation were conducted to understand the influences of rod diameter, height-width ratio, number of unites and layers on the mechanical properties of PK lattice material. The failure characteristics and the deformation process were recorded by using the digital photography technique. All the specimens were observed to have a clear rupture along 45°in the quasi-static test, while broke along the direction of the vertical panel in the SHPB test with a strain rate of about 2000s−1.The results showed that the initial deformation zone of the PK switched from the intermediate layer to the lower and upper layer with the increase of rod diameter. Moreover, the strength, modulus and energy absorption capacity of the PK were proportional to the square of its relative density. As the height-width ratio increases, the modulus of the PK gradually increased. In addition, increasing the number of lateral units and reducing the number of layers contributed to the improvement on the mechanical properties of the PK.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Background Knowledge on the long-term development of adiposity throughout childhood/adolescence and its prenatal determinants and health sequelae is lacking. We sought to (1) identify trajectories of ...Body Mass Index (BMI) from 1 to 18 years of age, (2) examine associations of maternal gestational smoking and early pregnancy overweight with offspring BMI trajectories and (3) determine whether BMI trajectories predict health outcomes: asthma, lung function parameters (forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio), and blood pressure, at 18 years. Methods The Isle of Wight birth cohort, a population-based sample of 1456 infants born between January 1989 and February 1990, was prospectively assessed at ages 1, 2, 4, 10 and 18 years. Group-based trajectory modelling was applied to test for the presence of latent BMI trajectories. Associations were assessed using log-binomial and linear regression models. Results Four trajectories of BMI were identified: ‘normal’, ‘early persistent obesity’, ‘delayed overweight’, and ‘early transient overweight’. Risk factors for being in the early persistent obesity trajectory included maternal smoking during pregnancy (RR 2.16, 95% CI 1.02 to 4.68) and early pregnancy overweight (3.16, 1.52 to 6.58). When comparing the early persistent obesity to the normal trajectory, a 2.15-fold (1.33 to 3.49) increased risk of asthma, 3.2% (0.4% to 6.0%) deficit in FEV1/FVC ratio, and elevated systolic 11.3 mm Hg (7.1 to 15.4) and diastolic 12.0 mm Hg (8.9 to 15.1) blood pressure were observed at age 18 years. Conclusions Maternal prenatal exposures show prolonged effects on offspring's propensity towards overweight-obesity. Distinct morbid BMI trajectories are evident during the first 18 years of life that are associated with higher risk of asthma, reduced FEV1/FVC ratio, and elevated blood pressure.
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BFBNIB, CMK, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Most of the current methods for the synthesis of two-dimensional materials (2DMs) require temperatures not compatible with traditional back-end-of-line (BEOL) processes in semiconductor industry (450 ...°C). Here, we report a general BiOCl-assisted chemical vapor deposition (CVD) approach for the low-temperature synthesis of 27 ultrathin 2DMs. In particular, by mixing BiOCl with selected metal powders to produce volatile intermediates, we show that ultrathin 2DMs can be produced at 280-500 °C, which are ~200-300 °C lower than the temperatures required for salt-assisted CVD processes. In-depth characterizations and theoretical calculations reveal the low-temperature processes promoting 2D growth and the oxygen-inhibited synthetic mechanism ensuring the formation of ultrathin nonlayered 2DMs. We demonstrate that the resulting 2DMs exhibit electrical, magnetic and optoelectronic properties comparable to those of 2DMs grown at much higher temperatures. The general low-temperature preparation of ultrathin 2DMs defines a rich material platform for exploring exotic physics and facile BEOL integration in semiconductor industry.
Since the 2000s, an era of big data has emerged. Since then, urban planners have increasingly applied the theory and methods of big data in planning practice. Recent decades illustrate a rapid ...increase of the application of big data approaches in transportation, bringing new opportunities for innovation in transport modeling. This article analyzes the theories and methods of big data in traffic demand forecasting. In view of theory, the new models and algorithms are proposed in order to adapt to new big data and response to the limitations of traditional disaggregated approaches. In such approaches, three traffic demand-forecasting methods, the full sample-demand distribution model, the traffic integration model, the model organism protein expression database model, are discussed. Undoubtedly, the development of big data also presents new challenges to travel-demand forecasting methods regarding data acquisition, data processing, data analysis, and application of results. In particular, identifying how to improve approaches to traffic-demand forecasting in the big data era in the Third World will be a challenge to the researchers in the field.
•Big data brings new opportunities for the innovation of transport modeling•The new models and algorithms are proposed responding to the limitations of the traditional disaggregated approaches.•Full sample demand distribution model, Traffic integration model, and MoPeD model are discussed.•Improvement of traffic demand forecasting approaches in the big data era in the Third World will be a challenge.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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