To evaluate apparent diffusion coefficient (ADC) and its standard deviation (SD
) in preoperative predicting liver invasion by T3-staged gallbladder carcinoma (GBC).
Forty-one consecutive patients ...with T3-staged resectable GBC were included and divided into two sets with (n=27) and without (n=14) liver invasion. All patients underwent DWI at b-values of 0, 20, 50, 80, 100, 200, 400, 600, 800, and 1,000 s/mm
with a 3 T magnetic resonance imaging scanner before surgery. ADC and SD
of tumour-adjacent and tumour-distant liver tissues were measured on DWI, and were compared by Mann-Whitney U-tests. If there was a significant difference in any derived parameter, the area under the receiver operating characteristic curve (AUC) was used to assess performance of this parameter to predict liver invasion.
DWI could differentiate between patients with and without liver invasion when b = 0, 1,000 s/mm
(AUCs of ADC and SD
were 0.697 and 0.714, respectively). In patients with liver invasion, mean ADC and SD
of tumour-adjacent liver tissue were lower than of tumour-distant liver tissue when b = 0, 800 s/mm
, and = 0, 1,000 s/mm
(all p-values <0.05). To differentiate tumour-adjacent from tumour-distant liver tissues in patients with liver invasion, AUCs of ADC were 0.687 (b = 0, 800 s/mm
) and 0.680 (b = 0, 1,000 s/mm
), and AUCs of SD
were 0.673 (b = 0, 800 s/mm
) and 0.731 (b = 0, 1,000 s/mm
).
DWI could have potential value in preoperative predicting liver invasion by T3-staged GBC.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Objectives
This study aimed to explore the association between number of teeth and cognitive frailty in American older adults.
Design
Cross-sectional study.
Setting
Community.
Participants
The ...participants were 1,531 community-dwelling older adults aged 60 or older from the NHANES database.
Methods
Frailty was assessed using a 49-item frailty index, with a cut-off value for frailty of more than 0.21. Cognitive dysfunction was evaluated by the Digit-Symbol Coding Test (DSCT), with the cut-off being below the lowest interquartile range (scores ≤37). Cognitive frailty was defined as participants who suffered from both frailty and cognitive dysfunction. Oral health indicators included number of teeth and other factors, such as the presence of gum disease, daily use of dental floss, daily use of mouthwash and self-rated oral health. Multivariable logistic regression models were used to explore the relationship between number of teeth and cognitive frailty.
Results
The mean age of the total sample was 69.67 (SD=6.60) years, and 52.71% (n=807) were female. Our study suggests there was a negative association between number of teeth and cognitive frailty (OR =0.98,95%CI:0.96–0.99, P=0.044) after controlling for potential confounding factors. In addition, older adults with 20 or more teeth had lower odds of being cognitively frail (OR=0.66,95%CI:0.44–0.99, P=0.046) than individuals who had less than 20 teeth.
Conclusion
This study suggests that older adults who have more teeth are associated with a lower risk of cognitive frailty. This finding highlights the importance of maintaining as many teeth as possible throughout life and into old age. Cohort studies will be required in the future to determine this relationship.
Since the pandemic organizations have been required to build agility to manage risks, stakeholder engagement, improve capabilities and maturity levels to deliver on strategy. Not only is there a ...requirement to improve performance, a focus on employee engagement and increased use of technology have surfaced as important factors to remain competitive in the new world. Consideration of the strategic horizon, strategic foresight and support structures is required to manage critical factors for the formulation, execution and transformation of strategy. Strategic foresight and Artificial Intelligence modelling are ways to predict an organizations future agility and potential through modelling of attributes, characteristics, practices, support structures, maturity levels and other aspects of future change. The application of this can support the development of required new competencies, skills and capabilities, use of tools and develop a culture of adaptation to improve engagement and performance to successfully deliver on strategy. In this paper we apply an Artificial Intelligence model to predict an organizations level of future agility that can be used to proactively make changes to support improving the level of agility. We also explore the barriers and benefits of improved organizational agility. The research data was collected from 44 respondents in public and private Australian industry sectors. These research findings together with findings from previous studies identify practices and characteristics that contribute to organizational agility for success. This paper contributes to the ongoing discourse of these principles, practices, attributes and characteristics that will help overcome some of the barriers for organizations with limited resources to build a framework and culture of agility to deliver on strategy in a changing world.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
AbstractSlender bridges, often built in harsh coastal environments, may experience dynamic loadings from strong winds and high waves. Busy traffic is expected during normal operating conditions and ...during evacuation events before extreme weather or emergency-related conditions. Understanding the dynamics of the complex vehicle-bridge-wind-wave (VBWW) system is critical to the safety of both vehicles and bridges. For the present study, an analytical model was developed to evaluate the dynamic performance of the coupled VBWW system. First, the bridge was discretized using the FEM, and vehicles were modeled as mass-spring-damper systems to build the equations for the dynamic equilibrium. Then, the time histories of the wind and wave around the bridge site were simulated as stochastic random processes and generated using the spectral representation method. The dynamic system integrated the conventional buffeting analysis for the wind–bridge interaction, the quasi-static analysis for the wind–vehicle interaction, and the dynamic interaction between the moving vehicles and the bridge according to the geometric and mechanical relationships between the vehicle tires and the bridge deck. In addition, the interaction between the wave and bridge group-pile foundation was included in the system using the Morrison equation. Finally, for demonstration purposes, the dynamic responses of a coastal slender cable-stayed bridge under different vehicle-, wind-, and wave-loading scenarios were analyzed. The case study results indicated that the lateral vibration of the prototype bridge can increase by 13.6–82.4% for different components of the bridge under different lateral incident wave scenarios with varied wave heights and frequencies. The coupled VBWW results also indicated that wind load was the predominant dynamic response of both the vehicle and bridge with slight loading effects from the waves.
A composite polymer membrane is prepared by coating poly(vinylidene fluoride) (PVDF) on the surface of a membrane based on methyl cellulose (MC) which is environmentally friendly and cheap. Its ...characteristics are investigated by scanning electron microscopy, FT-IR, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The outer PVDF layers are porous which results in high electrolyte uptake and the lithium ion transference number is much larger than that of the pure MC. Moreover, the cell based on Li//LiFePO4 delivers high discharge capacity and good rate behavior in the range of 4.2–2.5 V when the composite membrane is used as the separator and the host of a gel polymer electrolyte, lithium as the counter and reference electrode, and LiFePO4 as cathode. The obtained results suggest that this unique composite membrane shows great attraction in the lithium ion batteries with high safety and low cost.
A composite membrane, PVDF/MC/PVDF, is successfully made. As a host for gel polymer electrolyte, it delivers high lithium ion transference number and good mechanical performance. When used as separator in lithium ion batteries, it shows excellent rate behaviour and cycling performance. Display omitted
•Methyl cellulose (MC) is environmentally friendly and cheap.•A composite polymer membrane is prepared by coating PVDF on the surface of a membrane from MC.•The composite membrane is used as the separator and the host of a gel polymer electrolyte.•The prepared gel polymer electrolyte shows excellent electrochemical performance.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We report a detailed study of the strain hardening behavior of a Fe–16Mn–10Al–0.86C–5Ni (weight percent) high specific strength (i.e. yield strength-to-mass density ratio) steel (HSSS) during ...uniaxial tensile deformation. The dual-phase (γ-austenite and B2 intermetallic compound) HSSS possesses high yield strength of 1.2–1.4 GPa and uniform elongation of 18–34%. The tensile deformation of the HSSS exhibits an initial yield-peak, followed by a transient characterized by an up-turn of the strain hardening rate. Using synchrotron based high-energy in situ X-ray diffraction, the evolution of lattice strains in both the γ and B2 phases was monitored, which has disclosed an explicit elasto-plastic transition through load transfer and strain partitioning between the two phases followed by co-deformation. The unloading-reloading tests revealed the Bauschinger effect: during unloading yield in γ occurs even when the applied load is still in tension. The extraordinary strain hardening rate can be attributed to the high back stresses that arise from the strain incompatibility caused by the microstructural heterogeneity in the HSSS.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Migmatite gneisses are widespread in the Dabie orogen, but their formation ages are poorly constrained. Eight samples of migmatite, including leucosome, melanosome, and banded gneiss, were selected ...for U–Pb dating and Hf isotope analysis. Most metamorphic zircon occurs as overgrowths around inherited igneous cores or as newly grown grains. Morphological and internal structure features suggest that their growth is associated with partial melting. According to the Hf isotope ratio relationships between metamorphic zircon and inherited cores, three formation mechanisms for metamorphic zircon can be determined, which are dissolution–reprecipitation of pre‐existing zircon, breakdown of Zr‐bearing phase other than zircon in a closed system and crystallization from externally derived Zr‐bearing melt. Four samples contain magmatic zircon cores, yielding upper intercept U–Pb ages of 807 ± 35–768 ± 12 Ma suggesting that the protoliths of the migmatites are Neoproterozoic in age. The migmatite zircon yields weighted mean two‐stage Hf model ages of 2513 ± 97–894 ± 54 Ma, indicating reworking of both juvenile and ancient crustal materials at the time of their protolith formation. The metamorphic zircons give U–Pb ages of 145 ± 2–120 ± 2 Ma. The oldest age indicates that partial melting commenced prior to 145 Ma, which also constrains the onset of extensional tectonism in this region to pre‐145 Ma. The youngest age of 120 Ma was obtained from an undeformed granitic vein, indicating that deformation in this area was complete at this time. Two major episodes of partial melting were dated at 139 ± 1 and 123 ± 1Ma. The first episode of partial melting is obviously older than the timing of post‐collision magmatism, corresponding to regional extension. The second episode of partial melting is coeval with the widespread post‐collision magmatism, indicating the gravitational collapse and delamination of the orogenic lithospheric keel of the Dabie orogen, which were possibly triggered by the uprising of the Cretaceous mid‐Pacific superplume.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To build a nomogram model to improve the evaluation of revascularisation necessity using multi-parameter coronary computed tomography (CT) angiography (CCTA).
In this retrospective study, 335 ...patients who underwent CCTA and required revascularisation within 1 month were selected and allocated to the revascularisation group; 208 patients who did not undergo revascularisation were allocated to the non-revascularisation group. CCTA parameters, including CCTA stenosis, plaque qualitative–quantitative characteristics, and fractional flow reserve derived from CT angiography (CT-FFR), for both groups were analysed and compared. Independent risk factors for evaluating revascularisation were obtained using univariate and multivariable regression analysis, after which multi-parameter models were built. Finally, a nomogram was created with these independent risk factors using the R programming language.
Plaque analysis was performed successfully for 543 patients with 1,072 target plaques. The performance of the multi-parameter model (AUC 0.894, p<0.001) was significantly higher than that of models based on stenosis (AUC 0.804, p<0.001), plaque qualitative/quantitative characteristics (AUC 0.754/0.789, p<0.001), or CT-FFR (AUC 0.848, p<0.001) alone, to evaluate the necessity of revascularisation. The independent risk factors were CCTA stenosis (OR 1.004, p=0.04), positive remodelling (OR 2.474, p<0.001), total plaque volume (OR 1.001, p<0.001), non-calcified plaque volume proportion (OR 1.019, p<0.001), and CT-FFR (OR 0.001, p<0.001). Subsequently, a nomogram based on these factors was created.
The multi-parameter CCTA model improved performance in evaluating revascularisation necessity. The nomogram based on these factors is shows promise in clinical settings.
•The multi-parameter CCTA model has good performance for evaluting revascularization.•Nomogram we created is promising in the clinical setting.•ParaMeters in nomogram were CCTA stenosis, PR, TPV, NCPVP, and CT-FFR.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
We present an empirical stellar spectra library created using spectra from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR5. This library represents a uniform data set ...ranging from 3750 through 8500 K in effective temperature (Teff), from −2.5 through +1.0 dex in metallicity (Fe/H), and from 0 to 5.0 dex in gravity (log g). The spectra in the library have resolutions R ∼ 1800, with well-calibrated fluxes and rest-framed wavelengths. Using a large number of red stars observed by LAMOST, we generated denser K-type templates to fill in data missing from current empirical spectral libraries, particularly the late K type. For K giants, we calibrated the spectroscopic surface gravities against the asteroseismic surface gravities. To verify the reliability of the parameters labeled for this library, we performed an internal cross-validation using a χ2 minimization method to interpolate the parameters of each individual spectrum using the remaining spectra in the library. We obtained precisions of 41 K, 0.11 dex, and 0.05 dex for Teff, log g, and Fe/H, respectively, which means the templates are labeled with correct stellar parameters. Through external comparisons, we confirmed that measurements of the stellar parameters through this library can achieve accuracies of approximately 125 K in Teff, 0.1 dex in Fe/H and 0.20 dex in log g without systematic offset. This empirical library is useful for stellar parameter measurements because it has large parameter coverage and full wavelength coverage from 3800 to 8900 .
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