Alloying is an effective method to strengthen high entropy alloys (HEAs). Unfortunately, most of the investigations focus on the perspective of experiments and few are available from the perspective ...of atomic and electrical scale such as electronic structure, energy band structure and charge density. In present work, first-principle calculation based on density functional theory was employed to calculate the ground state total energy, lattice parameters, elastic constants and polycrystal modulus of NbMoTaW and NbMoTaWV refractory high entropy alloys (RHEAs). The effects of V addition on the phase structure, elastic properties and electronic structure of NbMoTaW-based RHEAs were studied, respectively. V addition is helpful to improve the mechanical properties of NbMoTaW alloy according to the calculated value of shear modulus to bulk modulus, Cauchy pressure and Vickers hardness. Based on calculated energy band, electronic state density, charge density and charge density difference, V addition is found to shorten the pseudo-energy gap and enhance interaction force between Mo and W atoms. This tends to improve the mechanical properties of the alloy. The calculated results were in good agreement with the experimental data, demonstrating that the methods were effective in predicting the performance of RHEAs.
•V strengthening of NbMoTaW HEA was investigated from perspective of atomic and electrical scale.•Interaction of orbitals electrons between V and Nb–Mo–Ta–W is stronger than that among Nb–Mo–Ta–W.•V addition enhances the bonding strength and improves mechanical properties of NbMoTaW RHEA.
Solar steam generation with subsequent steam recondensation has been regarded as one of the most promising techniques to utilize the abundant solar energy and sea water or other unpurified water ...through water purification, desalination, and distillation. Although tremendous efforts have been dedicated to developing high‐efficiency solar steam generation devices, challenges remain in terms of the relatively low efficiency, complicated fabrications, high cost, and inability to scale up. Here, inspired by the water transpiration behavior of trees, the use of carbon nanotube (CNT)‐modified flexible wood membrane (F‐Wood/CNTs) is demonstrated as a flexible, portable, recyclable, and efficient solar steam generation device for low‐cost and scalable solar steam generation applications. Benefitting from the unique structural merits of the F‐Wood/CNTs membrane—a black CNT‐coated hair‐like surface with excellent light absorbability, wood matrix with low thermal conductivity, hierarchical micro‐ and nanochannels for water pumping and escaping, solar steam generation device based on the F‐Wood/CNTs membrane demonstrates a high efficiency of 81% at 10 kW cm−2, representing one of the highest values ever‐reported. The nature‐inspired design concept in this study is straightforward and easily scalable, representing one of the most promising solutions for renewable and portable solar energy generation and other related phase‐change applications.
A nature‐inspired steam‐generation materialof flexible wood/CNTs composite membrane is developed directly from natural wood. Systematic optimizations of water transportation, thermal management, and light absorption and thus high water evaporating efficiency can be realized by using the nature‐made channels in wood for efficient water transportation, intrinsic thermal‐insolating wood matrix as thermal barrier, and CNT‐coated surface as light absorber.
Equilibrium condensation of solar gas is often invoked to explain the abundance of refractory elements in planets and meteorites. This is partly motivated, by the observation that the depletions in ...both the least and most refractory rare earth elements (REEs) in meteoritic group II calcium-aluminum-rich inclusions (CAIs) can be reproduced by thermodynamic models of solar nebula condensation. We measured the isotopic compositions of Ce, Nd, Sm, Eu, Gd, Dy, Er, and Yb in eight CAIs to test this scenario. Contrary to expectation for equilibrium condensation, we find light isotope enrichment for the most refractory REEs and more subdued isotopic variations for the least refractory REEs. This suggests that group II CAIs formed by a two-stage process involving fast evaporation of preexisting materials, followed by near-equilibrium recondensation. The calculated time scales are consistent with heating in events akin to FU Orionis- or EX Lupi-type outbursts of eruptive pre-main-sequence stars.
We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass p-type point-contact germanium detector of the CDEX-1B ...experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2-yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus (χ-N) spin-independent cross sections as function of WIMP mass (m_{χ}) at 90% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at >99.99% and 98% C.L., respectively. These results correspond to the best sensitivity at m_{χ}<6 GeV/c^{2} among WIMP AM measurements to date.
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
Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from ...astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.
Summary
Increasing evidence has suggested that the host inflammatory status is associated with prognosis of several solid tumors. Preoperative platelet–lymphocyte ratio (PLR) and ...neutrophil–lymphocyte ratio (NLR), both acquired from routine blood tests, can reflect the status of systematic inflammation. However, whether they are correlated with clinical outcomes of esophageal carcinoma is still unknown. The purpose of this study was to determine the prognostic value of preoperative PLR and NLR in patients with resected esophageal squamous cell carcinoma (ESCC). Preoperative PLR and NLR were evaluated in 317 eligible ESCC patients from September 2008 to December 2010. Receiver operating characteristic curves were applied to establish optimal cutoff points. The prognostic values of PLR and NLR were determined by both univariate and multivariate analyses. The optimal cutoff value of preoperative PLR and NLR were 103.0 and 2.1, respectively. One hundred and ninety‐seven (62.1%) patients showed high level of preoperative PLR, while 148 (46.7%) patients showed high level of preoperative NLR. Both elevated PLR (P < 0.001) and NLR (P = 0.009) were correlated with poor disease‐specific survival in univariate analysis. However, only preoperative PLR (P = 0.003) had a significant correlation with prognosis in multivariate analysis. In subgroup analyses, the predictive value of PLR was significant for stage I (P = 0.008) and stage II (P = 0.044) patients, but not for stage III patients (P = 0.100). Preoperative PLR is easily obtained from a routine blood test and may provide additional prognostic information for ESCC patients, especially in the early stage.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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