Background
Hepatic vein tumour thrombus (HVTT) is a major determinant of survival outcomes for patients with hepatocellular carcinoma (HCC). An Eastern Hepatobiliary Surgery Hospital (EHBH)‐HVTT ...model was established to predict the prognosis of patients with HCC and HVTT after liver resection, in order to identify optimal candidates for liver resection.
Methods
Patients with HCC and HVTT from 15 hospitals in China were included. The EHBH‐HVTT model with contour plot was developed using a non‐linear model in the training cohort, and subsequently validated in internal and external cohorts.
Results
Of 850 patients who met the inclusion criteria, there were 292 patients who had liver resection and 198 who did not in the training cohort, and 124 and 236 in the internal and external validation cohorts respectively. Contour plots for the EHBH‐HVTT model were established to predict overall survival (OS) rates of patients visually, based on tumour diameter, number of tumours and portal vein tumour thrombus. This differentiated patients into low‐ and high‐risk groups with distinct long‐term prognoses in the liver resection cohort (median OS 34·7 versus 12·0 months; P < 0·001), internal validation cohort (32·8 versus 10·4 months; P = 0·002) and external validation cohort (15·2 versus 6·5 months; P = 0·006). On subgroup analysis, the model showed the same efficacy in differentiating patients with HVTT in peripheral and major hepatic veins, the inferior vena cava, or in patients with coexisting portal vein tumour thrombus.
Conclusion
The EHBH‐HVTT model was accurate in predicting prognosis in patients with HCC and HVTT after liver resection. It identified optimal candidates for liver resection among patients with HCC and HVTT, including tumour thrombus in the inferior vena cava, or coexisting portal vein tumour thrombus.
Antecedentes
La trombosis tumoral de la vena hepática (hepatic vein tumour thrombus, HVTT) es un determinante importante de los resultados de supervivencia en pacientes con carcinoma hepatocelular (hepatocellular carcinoma, HCC). Se desarrolló el modelo llamado Eastern Hepatobiliary Surgery Hospital (EHBH)‐HVTT para predecir el pronóstico de los pacientes con HCC y HVTT después de la resección hepática (liver resection, LR), con el fin de identificar los candidatos óptimos para LR entre estos pacientes.
Métodos
Se incluyeron pacientes con HCC y HVTT de 15 hospitales en China. El modelo EHBH‐HVTT con gráfico de contorno se desarrolló utilizando un modelo no lineal en la cohorte de entrenamiento, siendo posteriormente validado en cohortes internas y externas.
Resultados
De 850 pacientes que cumplieron con los criterios de inclusión, hubo 292 pacientes en el grupo LR y 198 pacientes en el grupo no LR en la cohorte de entrenamiento, y 124 y 236 en las cohortes de validación interna y externa. Los gráficos de contorno del modelo EHBH‐HVTT se establecieron para predecir visualmente las tasas de supervivencia global (overall survival, OS) de los pacientes, en función del diámetro del tumor, número de tumores y del trombo tumoral de la vena porta (portal vein tumour thrombus, PVTT). Esto diferenciaba a los pacientes en los grupos de alto y bajo riesgo, con distinto pronóstico a largo plazo en las 3 cohortes (34,7 versus 12,0 meses, 32,8 versus 10,4 meses y 15,2 versus 6,5 meses, P < 0,001). En el análisis de subgrupos, el modelo mostró la misma eficacia en la diferenciación de pacientes con HVTT, con trombo tumoral en la vena cava inferior (inferior vena cava tumour thrombus, IVCTT) o en pacientes con PVTT coexistente.
Conclusión
El modelo EHBH‐HVTT fue preciso para la predicción del pronóstico en pacientes con HCC y HVTT después de la LR. Identificó candidatos óptimos para LR en pacientes con HCC y HVTT, incluyendo IVCTT o PVTT coexistente.
The Eastern Hepatobiliary Surgery Hospital–hepatic vein tumour thrombus (EHBH‐HVTT) model was accurate in predicting prognosis in patients with hepatocellular carcinoma (HCC) and HVTT after liver resection. It identified optimal candidates for liver resection among patients with HCC and HVTT, including inferior vena cava tumour thrombus, or coexisting portal vein tumour thrombus (PVTT).
predicts prognosis
•Evaluate the performances of four inflow turbulence generation methods.•Identify their advantages and limitations for LES of wind effects on tall building.•Provide remedial measures to improve the ...performances of the methods.•Propose a procedure for accurate LES of wind effects on tall building.
Generation of turbulent inflow conditions matching realistic wind flow characteristics in atmospheric boundary layer (ABL) is essential for accurate predictions of wind effects on buildings and structures using large eddy simulation (LES). It is thus necessary to evaluate the performances of different inflow turbulence generation techniques. In this study, four inflow turbulence generation methods (including three synthetic turbulence methods and the recycling method) were used to simulate wind flows in ABL for LES of wind loadings on a tall building. The advantages and limitations of these inflow turbulence generation methods were discussed through comparisons with available wind tunnel measurements and previous numerical simulation results. Several remedial measures were presented to improve the performances of these inflow turbulence generation methods. The findings of this paper are of use and interest to researchers and designers involved in the wind-resistant design of tall buildings, since one can follow the established procedure to predict the dynamic wind loadings on tall buildings by LES.
ABSTRACT Millisecond magnetars can be formed via several channels: core collapse of massive stars, accretion-induced collapse of white dwarfs (WDs), double WD mergers, double neutron star (NS) ...mergers, and WD-NS mergers. Because the mass of ejecta from these channels could be quite different, their light curves are also expected to be diverse. We evaluate the dynamic evolution of optical transients powered by millisecond magnetars. We find that the magnetar with a short spin-down timescale converts its rotational energy mostly into the kinetic energy of the transient, while the energy of a magnetar with a long spin-down timescale goes into radiation of the transient. This leads us to speculate that hypernovae could be powered by magnetars with short spin-down timescales. At late times the optical transients will gradually evolve into a nebular phase because of the photospheric recession. We treat the photosphere and nebula separately because their radiation mechanisms are different. In some cases the ejecta could be light enough that the magnetar can accelerate it to a relativistic speed. It is well known that the peak luminosity of a supernova (SN) occurs when the luminosity is equal to the instantaneous energy input rate, as shown by Arnett. We show that photospheric recession and relativistic motion can modify this law. The photospheric recession always leads to a delay of the peak time relative to the time at which the SN luminosity equals the instantaneous energy input rate. Relativistic motion, however, may change this result significantly.
Multi-photon production in the Type-I 2HDM Arhrib, A.; Benbrik, R.; Moretti, S. ...
The journal of high energy physics,
07/2018, Letnik:
2018, Številka:
7
Journal Article
Recenzirano
Odprti dostop
A
bstract
This paper presents a study of a possible contribution to a Higgs boson signal in the
hh
→
γγγγ
channel due to
H
→
hh
decays, in the framework of the CP-conserving 2-Higgs Doublet Model ...Type-I (2HDM-I), where the heavier of the two CP-even Higgs bosons defined herein,
H
, is the SM-like Higgs state observed with a mass of 125 GeV at the Large Hadron Collider (LHC). We perform a broad scan of the 2HDM-I parameter space, in presence of both up-to-date theoretical and experimental constraints, in order to extract the interesting regions yielding such a signal. Then, after validating our numerical framework against public experimental analyses carried out at the LHC, we proceed to assess its scope in constraining and/or extracting the
gg
→
H
→
hh
→
γγγγ
signal in presence of a sophisticated Monte Carlo (MC) simulation. We find that, over a substantial region of the 2HDM-I parameter space presently un-accessible, the LHC will be able to establish such a potential signature in the next 2–3 years.
In order to develop high strength metal–matrix composites with acceptable ductility, bulk nanostructured aluminum–matrix composites reinforced with graphene nanoflakes were fabricated by cryomilling ...and hot extrusion processes. Microstructure and mechanical properties were characterized and determined using transmission electron microscopy, electron dispersion spectroscopy, as well as static tensile tests. The results show that, with an addition of only 0.5wt% graphene nanoflakes, the bulk nanostructured aluminum/graphene composite exhibited increased strength and unsubdued ductility over pure aluminum. Besides, the mechanical properties of the composites with higher content of graphene nanoflakes were also measured and investigated. Above 1.0wt% of graphene nanoflakes, however, this strengthening effect sharply dropped due to the clustering of graphene nanoflakes. Furthermore, the optimal addition of graphene nanoflakes into the nanocrystalline aluminum matrix was calculated and discussed.
The pilot-scale pyrolysis of scrap tires in a continuous rotary kiln reactor was investigated at temperatures between 450 and 650 °C. As the reactor temperature increased, the char yield remained ...constant with a mean of 39.8 wt %. The oil yield reached a maximum value of 45.1 wt % at 500 °C. The pyrolytic derived oils can be used as liquid fuels because of their high heating value (40−42 MJ/kg), excellent viscosity (1.6−3.7 cS), and reasonable sulfur content (0.97−1.54 wt %). The true-boiling-point distillation test showed that there was a 39.2−42.3 wt % light naphtha fraction in the pyrolytic oil. The volatile aromatics were quantified in the naphtha fraction using gas chromatography−mass spectrometry. The maximum concentrations of benzene, toluene, xylene, styrene, and limonene in the oil were 2.09 wt %, 7.24 wt %, 2.13 wt %, and 5.44 wt %, respectively. The abundant presence of aromatic groups was also confirmed by functional group Fourier transform infrared analysis. The concentration of polycyclic aromatic hydrocarbons such as fluorine, phenanthrene, and anthracene increased with increasing temperature. The pyrolytic char was composed of mesopores with a Brunauer−Emmett−Teller (BET) surface area of about 89.1 m2/g. The char after carbon dioxide activation had a high BET surface area of 306 m2/g at 51.3% burnoff. The relationship between the surface area and the carbon burnoff was almost linear. Both the original pyrolytic char and the activated char have good potential for use as adsorbents of relatively large molecular species.
•A coupled on-site measurement/CFD based approach is proposed.•It can reproduce spatial variability of wind speed over complex terrains.•A framework is presented for efficient and reliable wind ...resource assessment.•A cross-validation study verifies the accuracy of the proposed method.•The new method facilitates wind energy development in areas with complex terrains.
Wind resource assessment is essential for development of wind energy, particularly in the regions with complex terrains. This study proposes a coupled on-site measurement/CFD (Computational Fluid Dynamics) based approach to reproduce the spatial variability of wind speed for a region with complex terrain conditions. A complete framework is presented for wind resource assessment, which involves on-site measurement, CFD simulations and statistical analysis. Next, a case study on wind resource assessment for an offshore island with complex terrain features where is equipped with anemometers for long-term wind measurement is performed using the developed approach. The microscale effects in the assessment region are justified from CFD simulations with modified RNG k–ε model. A cross-validation of the numerical simulations against wind tunnel experimental results and on-site measurements indicates a good agreement. Consequently, a detailed wind resource map of the offshore island is attained through the wind data from a single measurement site combined with the CFD simulations, which is of great use for future wind farm siting and turbine micro-siting. The coupled on-site measurement/CFD based approach is expected to enable the efficient and reliable wind resource assessment and facilitate the wind energy development in the areas with complex terrain conditions.
The AlCrMoNiTi and AlCrMoZrTi nitride films were prepared by reactive radio-frequency (RF) magnetron sputtering at various N2-to-Ar flow ratios (RN). The influence of RN on the structure and ...properties of these films was investigated. The two alloy films presented an amorphous structure, while a simple face-centered-cubic (FCC) solid-solution structure was observed in the nitride films prepared under different RN. As the RN increased, the clusters, defects and film thickness decreased, which resulted in a dense columnar structure and low surface roughness. Peak hardness of 19.6GPa for AlCrMoZrTi nitride films and 15.4GPa for AlCrMoNiTi nitride films were attained at RN=1.0 respectively. At RN=0.5, the friction coefficients of AlCrMoNiTi and AlCrMoZrTi nitride films were respectively 0.15 and 0.13. Moreover, the AlCrMoZrTi nitride films did not undergo wear-out after 1200s friction experiment. Therefore, The AlCrMoZrTi nitride films exhibited better mechanical properties than that of AlCrMoNiTi nitride films, which may be related to the fact that the solid-solution strengthening effect of Zr was greater than that of Ni.
•Two films were prepared by RF sputtering at various N2/Ar flow ratio (RN).•Two films had an amorphous and FCC phase at low and high RN, respectively.•(AlCrMoZrTi)Nx had the lowest friction coefficient of 0.13 among these films.•The mechanical properties of (AlCrMoZrTi)Nx outperform the (AlCrMoNiTi)Nx.•Solid-solution strengthening effect of Zr element stronger than Ni element.
Abstract
We present a polarization analysis of PSR J0941–39 and PSR J1107–5907, which exhibit transitions between being pulsars and rotating radio transients (RRATs), using the ultrawide-bandwidth ...low-frequency receiver on Murriyang, the Parkes 64 m radio telescope. The spectral index of each pulsar was measured, revealing distinct variations among different states. By using the rotating vector model, we determined that the geometry of the magnetosphere remains consistent between the RRAT state and the pulsar state for PSR J0941–39, with emissions originating from the same height in the magnetosphere. The occurrence of the RRAT state could be attributed to variations in currents within the pulsar’s magnetosphere. Our results suggest that the emission mechanism of an RRAT may share similarities with that of a typical pulsar.
Abstract
We report analysis of sub-Alfvénic magnetohydrodynamic (MHD) perturbations in the low-
β
radial-field solar wind employing the Parker Solar Probe spacecraft data from 2018 October 31 to ...November 12. We calculate wavevectors using the singular value decomposition method and separate MHD perturbations into three eigenmodes (Alfvén, fast, and slow modes) to explore the properties of sub-Alfvénic perturbations and the role of compressible perturbations in solar wind heating. The MHD perturbations show a high degree of Alfvénicity in the radial-field solar wind, with the energy fraction of Alfvén modes dominating (∼45%–83%) over those of fast modes (∼16%–43%) and slow modes (∼1%–19%). We present a detailed analysis of a representative event on 2018 November 10. Observations show that fast modes dominate magnetic compressibility, whereas slow modes dominate density compressibility. The energy damping rate of compressible modes is comparable to the heating rate, suggesting the collisionless damping of compressible modes could be significant for solar wind heating. These results are valuable for further studies of the imbalanced turbulence near the Sun and possible heating effects of compressible modes at MHD scales in low-
β
plasma.
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