Floral evolution in angiosperms is thought to be driven by pollinator‐mediated selection. Understanding flower integration and adaptation requires resolving the additive and nonadditive contributions ...of floral pollinator attraction and pollination efficiency traits to fitness components.
In this study, a flower manipulation experiment with a factorial design was used to study the adaptive significance of galea height (a putative attraction trait) and entrance width (a putative efficiency trait) in Aconitum gymnandrum Maxim. flowers. Simultaneously, phenotypic selection analysis was conducted to examine selection by pollinators on galea height, entrance width, nectar production and plant height.
Increased galea height increased the pollinator visitation rate, which confirmed its attractiveness function. Increasing floral entrance width by spreading the lower sepals increased the seed number per fruit without affecting pollinator visitation. This suggests a pollination efficiency role for the entrance width. The phenotypic selection analysis, however, did not provide evidence of pollinator‐mediated selection for either of these traist, but it did for plant height. According to the manipulation treatment and correlational selection results, the combined variation in galea height and entrance width of A. gymnandrum flowers did not have nonadditive effects on female reproductive success.
This study demonstrated the adaptive value of A. gymnandrum flowers through manipulation of an attractiveness trait and an efficiency trait. However, neither trait was associated with pollinator‐mediated selection. A combination of manipulating traits and determining current phenotypic selection could help to elucidate the mechanism of selection on floral traits involved in different functions and flower integration.
Flower traits of A. gymnandrum, including attracting and efficiency traits, can differentially affect pollinator visitation and seed production, but are not subject to current pollinator‐mediated selection.
China overtook the U.S. in 2011 to become the country filing the largest number of patent applications. Has China's patenting ascendancy been propelled by Chinese firms’ increasing technological ...sophistication or their much greater propensity to seek patents? Using a unique and never before used data set, where the State Intellectual Property Office (SIPO) patent records have been matched to their applicant firms by SIPO, we differentiate the two potential explanations by estimating a patent production function and by relating a firm's patents in force to its labor productivity. Our main findings are: 1) while the patenting surge has been an across-the-board phenomenon, most of the growth has come from the extensive margin of growth – firms that were not actively applying for patents in the past; 2) the correlation between patents and R&D and that between patents and labor productivity have become weaker, particularly for utility models and for the extensive margin of growth. These results suggest that non-innovation related motives for acquiring patents may have played an important role in the patenting surge.
Neoadjuvant therapy is recommended for locally advanced esophageal cancer, but the optimal strategy remains unclear. We aimed to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy ...(nCRT) versus neoadjuvant chemotherapy (nCT) followed by minimally invasive esophagectomy (MIE) for locally advanced esophageal squamous cell carcinoma (ESCC).
Eligible patients staged as cT3-4aN0-1M0 ESCC were randomly assigned (1 : 1) to the nCRT or nCT group stratified by age, cN stage, and centers. The chemotherapy, based on paclitaxel and cisplatin, was administered to both groups, while concurrent radiotherapy was added for the nCRT group; then MIE was carried out. The primary endpoint was 3-year overall survival. This study is registered with ClinicalTrials.gov (NCT03001596).
A total of 264 patients were eligible for the intention-to-treat analysis. By 30 November 2021, 121 deaths had occurred. The median follow-up was 43.9 months (interquartile range 36.6-49.3 months). The overall survival in the intention-to-treat population was comparable between the nCRT and nCT strategies hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.58-1.18; P = 0.28, with a 3-year survival rate of 64.1% (95% CI 56.4% to 72.9%) versus 54.9% (95% CI 47.0% to 64.2%), respectively. There were also no differences in progression-free survival (HR 0.83, 95% CI 0.59-1.16; P = 0.27) and recurrence-free survival (HR 1.07, 95% CI 0.71-1.60; P = 0.75), although the pathological complete response in the nCRT group (31/112, 27.7%) was significantly higher than that in the nCT group (3/104, 2.9%; P < 0.001). Besides, a trend of lower risk of recurrence was observed in the nCRT group (P = 0.063), while the recurrence pattern was similar (P = 0.802).
NCRT followed by MIE was not associated with significantly better overall survival than nCT among patients with cT3-4aN0-1M0 ESCC. The results underscore the pending issue of the best strategy of neoadjuvant therapy for locally advanced bulky ESCC.
•The CMISG1701 trial assessed the safety and efficacy of nCRT versus nCT followed by MIE for locally advanced bulky ESCC.•The nCRT followed by MIE strategy could not improve survival significantly compared with the nCT strategy.•The best strategy of neoadjuvant therapy for locally advanced bulky ESCC remains a pending issue.
•The solid–liquid phase change in metal foams is studied by phase field method.•The model is validated by comparing with the experimental and numerical results.•The effects of factors on the melting ...and solidification are investigated in detail.•The evolution of phase field, flow field and temperature field is obtained.•Kinetic undercooling in solidification is discussed.
A numerical study on the solid–liquid phase change in open-cell metal foams is carried out by the phase field method originated from the Ginzburg–Landau theory. The Brinkman–Forchheimer extended Darcy equation and the local thermal non-equilibrium model are adopted to take natural convection and the heat transfer between metal foams and phase change materials (PCMs) into consideration, respectively. The result proves that the phase field model is reliable and effective in modeling metal foam enhanced phase change heat transfer in thermal energy storage. The effects of key parameters, such as Rayleigh number, porosity and pore density, on the melting and solidification process are investigated and it is found that they have great influence on the solid–liquid phase change. The phase field, flow field and temperature distributions in the melting and solidification process are obtained. Furthermore, kinetic undercooling in the solidification process is studied. It is concluded that heat conduction through the ligament of metal foams plays a dominant role in the solid–liquid phase change and kinetic undercooling effect is weakened as kinetic coefficient decreases.
Pool boiling heat transfer of metal foams with gradient pore densities has been investigated at atmospheric pressure in saturated deionized water. The gradient foams are made of two foam layers. The ...foam materials are copper and nickel. Pore densities of foam layers are from 5PPI to 100PPI, while the porosity remains the fixed value of 0.98. A parametric study is performed by varying the foam pore size and thickness. The effects of alumina nanoparticles and surfactant (SDS) on pool boiling heat transfer of gradient metal foams are also investigated in the present study. Images of foam fiber deposited by nanoparticles are captured by SEM. Compared to single-layer foams, gradient metal foams significantly enhance pool boiling heat transfer and the enhancement is heavily dependent on foam thickness and pore density gradient. The effects of SDS and nanoparticles on pool boiling heat transfer of gradient foams are dependent on concentrations.
A nanocrystalline (NC) face-centered cubic FeNi2CoMo0.2V0.5 high-entropy alloy was produced by high pressure torsion (HPT). The evolutions of microhardness and microstructure of the NC alloy during ...subsequent isochronal annealing were investigated systematically by electron back-scattering diffraction (EBSD) and high-resolution transmission electron microscopy (HRTEM). It was found that nano-grains and deformation nano-twin lamella were obtained at outer disk edge after HPT process with a hardness plateau of 450 HV. Isochronal annealing below 600 °C induced an evident hardening without precipitation effect, due to the annihilation of mobile dislocations and sustained deformation twin barriers. Evident recrystallization and grain growth of the NC FeNi2CoMo0.2V0.5 high-entropy alloy occurred during isochronal annealing at temperatures higher than 600 °C. The activation energies of recrystallization and grain growth of the NC FeNi2CoMo0.2V0.5 high-entropy alloy were calculated to be 350 kJ/mol and 272 kJ/mol, respectively, corresponding to a slow defects recovery process and a swift GB migration process. The high thermal stability of the NC FeNi2CoMo0.2V0.5 high-entropy was mainly caused by kinetic sluggish diffusion effect and deformation twin boundaries with thermodynamic low boundary energy, which retarded the movements of dislocations and grain boundary.
With the intention to reduce Dy content in NdFeB based magnets, 50at.% Y substituting Dy was previously successfully employed to improve the remanence and thermal stability of the nanocomposite ...Nd0.8Dy0.210Fe84B6 alloy without the energy product reduction. In this work, introducing Zr into Y substituted alloys has enhanced the coercivity Hcj of the melt spun Nd0.8(Dy0.5Y0.5)0.210Fe84−xB6Zrx alloys. With increasing x value from 0 to 2, Hcj increased from 575 to 814kA/m. Doping 2at.% Zr reduced the absolute value of the temperature coefficient β from 0.394 to 0.348%/°C. Good magnetic properties with Hcj of 797kA/m, maximum energy product (BH)max of 131kJ/m3 and β of −0.356%/°C were obtained for x=1.5. Both the Curie temperature and lattice constants of the hard magnetic phase decreased with Zr addition, indicating that Zr atoms can substitute directly into the hard phase, although some atoms may also locate outside the lattice. Together with the analysis on the demagnetization curve and recoil loops, the results verified that a small amount of Zr can improve the coercivity, thermal stability and exchange coupling of nanocomposite NdDyYFeB alloys through enhancing the anisotropy and improving the microstructure.
Background: Magnetic resonance (MR) imaging has been established as the best imaging modality for the detection, localization, and staging of prostate cancer on account of its high resolution of soft ...tissue and the possibilities of multiplanar and multiparameter scanning.
Purpose: To evaluate T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), MR spectroscopy (MRS), and the combination of these three MR techniques in the diagnosis of prostate cancer, as correlated to histopathologic findings.
Material and Methods: MR imaging, including T2WI, DWI, and MRS, was performed at 1.5T with a body coil combined with a spine coil in 42 cases. Diagnosis was confirmed by histopathology through systematic transrectal prostate biopsy. Apparent diffusion coefficient (ADC) maps were obtained with two b values (0 and 1000 s/mm2). The metabolic maps of 3D-MRS imaging were analyzed for the ratio of (Cho+Cre)/Cit in each sextant. All cases were evaluated by T2WI, DWI, and MRS, and then by the three methods combined. The statistical indicators and the receiver operating characteristic (ROC) curve analysis of each method were compared to the results of histopathology obtained by transrectal prostate biopsy.
Results: 15 of 42 cases were confirmed to be cancerous, and 27 of 42 cases were noncancerous. All the 252 sextants were confirmed by biopsies, including 201 benign sextants and 51 malignant sextants. The sensitivity and the specificity for the detection of prostate cancer were 88.2% and 67.2% for T2WI, as the cutoff was 3; 82.4% and 81.6% for DWI, as the cutoff was 4; 84.3% and 98.0% for MRS, as the cutoff was 5; and 96.1% and 96.5% for the combined T2WI+DWI+MRS, as the cutoff was 4. In the ROC analysis, the correlative areas under the ROC curves (Az) were 0.848±0.030, 0.860±0.033, and 0.961±0.016 for T2WI, DWI, and MRS, respectively, and 0.978±0.009 for the combination of T2WI+DWI+MRS.
Conclusion: The accuracy of the detection of prostate cancer is increased through a combination of the three techniques. Moreover, MRS demonstrated higher accuracy compared with T2WI or DWI.
•Structures of plain woven C/SiC composites are reconstructed at three scale levels.•A numerical model is proposed to predict thermal conductivities of the composites.•The in-yarn and out-of-yarn ...porosities are fully considered in the model.•Thermal conductivities with various fiber volume fractions and porosities are obtained.
Plain woven C/SiC composites have been widely applied in engineering thermal protective structures due to their excellent mechanical and physical properties. Plain woven C/SiC orthotropic composites are composed of carbon fibers, and in-yarn and out-of-yarn SiC matrixes with small air pores. Experimental studies on the effective thermal conductivities of plain woven C/SiC composites are rare due to their complex structure and costly processing technology. The effects of fiber volume fraction and porosity on the effective thermal conductivities can be revealed by numerical approach. In the present study, a finite volume numerical model at three scale levels is proposed on the basis of 3D geometric reconstructions with in-yarn and out-of-yarn porosities. The thermal conductivities of SiC matrix, woven yarn, and plain woven C/SiC composites are predicted using up-scaling approach. The proposed model is validated using available analytical and experimental results. The thermal conductivities of plain woven C/SiC composites decrease with the increment in carbon fiber volume fraction, and in-yarn and out-of-yarn porosities. The effect of out-of-yarn porosity on the thermal conductivities of the composites plays a dominant role. However, the occurrence of in-yarn porosity can lead to maximum decreases of 3.1% and 5.6% for in-plane and out-of-plane thermal conductivities respectively compared with the case without in-yarn porosity. The present work can provide a scientific guidance for the thermal design of plain woven C/SiC composites.
