Simultaneous modulated accelerated radiation therapy for esophageal cancer:A feasibility study

AIM:To establish the feasibility of simultaneous modulated accelerated radiation therapy(SMART) in esophageal cancer(EC).METHODS:Computed tomography(CT)datasets of 10patients with upper or middle thoracic squamous cell EC undergoing chemoradiotherapy were used to generate SMART,conventionally-fractionated three-dimensional conformal radiotherapy(3DCRT)and intensity-modulated radiation therapy(cf-IMRT)plans,respectively.The gross target volume(GTV)of the esophagus,positive regional lymph nodes(LN),and suspected lymph nodes(LN±)were contoured for each patient.The clinical target volume(CTV)was delineated with 2-cm longitudinal and 0.5-to 1.0-cm radial margins with respect to the GTV and with 0.5-cm uniform margins for LN and LN(±).For the SMART plans,there were two planning target volumes(PTVs):PTV66=(GTV+LN)+0.5 cm and PTV54=CTV+0.5 cm.For the 3DCRT and cfIMRT plans,there was only a single PTV:PTV60=CTV+0.5 cm.The prescribed dose for the SMART plans was 66 Gy/30 F to PTV66 and 54 Gy/30 F to PTV54.The dose prescription to the PTV60 for both the 3DCRT and cf-IMRT plans was set to 60 Gy/30 F.All the plans were generated on the Eclipse 10.0 treatment planning system.Fulfillment of the dose criteria for the PTVs received the highest priority,followed by the spinal cord,heart,and lungs.The dose-volume histograms were compared.RESULTS:Clinically acceptable plans were achieved for all the SMART,cf-IMRT,and 3DCRT plans.Compared with the 3DCRT plans,the SMART plans increased the dose delivered to the primary tumor(66Gy vs 60 Gy),with improved sparing of normal tissues in all patients.The Dmax of the spinal cord,V20 of the lungs,and Dmean and V50 of the heart for the SMART and 3DCRT plans were as follows:38.5±2.0 vs 44.7±0.8(P=0.002),17.1±4.0 vs 25.8±5.0(P=0.000),14.4±7.5 vs 21.4±11.1(P=0.000),and 4.9±3.4vs 12.9±7.6(P=0.000),respectively.In contrast to the cf-IMRT plans,the SMART plans permitted a simultaneous dose escalation(6 Gy)to the primary tumor while demonstrating a significant trend of a lower irradiation dose to all organs at risk except the spinal cord,for which no significant difference was found.CONCLUSION:SMART offers the potential for a 6Gy simultaneous escalation in the irradiation dose delivered to the primary tumor of EC and improves the sparing of normal tissues.

Investigation of the medium calcium based non-burnt brick made by red mud and fly ash: durability and hydration characteristics

Red mud is a type of highly alkaline waste residue produced in the process of alumina smelting by the Bayer process.Based on the idea of medium calcium content,solid wastes such as red mud and fly ash were used to prepare non-burnt bricks;and the mass ratio of CaO/SiO2 was selected in the range of 0.88–1.42.Mechanical properties and durability were investigated with a compressive strength test.X-ray diffractometry(XRD),scanning electron microscope(SEM),and Fourier transform infrared spectroscopy(FTIR)techniques were used to characterize the hydration characteristic.The environmental performance was analyzed by Inductively Coupled Plasma Mass Spectrometry(ICP).The results indicated that the mechanical properties and the durability were optimal when the mass ratio of CaO/SiO2 was 1.23.The hydration products were mostly C–S–H gel,ettringite,Na4Ca(Si10All6)O32·12H2O and Ca3Al2(SiO4)(OH)8.They were responsible for the strength development,and the CaO/SiO2 mass ratio of 1.23 had the best polymerized structure.The results of an environmental performance test showed that the heavy metals in the raw materials were well-solidified in the brick.Therefore,this paper provides an effective solution for use of solid wastes in building material.

Microstructure and electrolysis behavior of self-healing Cu-Ni-Fe composite inert anodes for aluminum electrowinning

The microstructure evolution and electrolysis behavior of(Cu_(52)Ni_(30)Fe_(18))–x Ni Fe_2O_4(x=40wt%,50wt%,60wt%,and 70wt%)composite inert anodes for aluminum electrowinning were studied.Ni Fe_2O_4 was synthesized by solid-state reaction at 950°C.The dense anode blocks were prepared by ball-milling followed by sintering under a N_2 atmosphere.The phase evolution of the anodes after sintering was determined by scanning electron microscopy and energy-dispersive X-ray spectroscopy.The results indicate that a substitution reaction between Fe in the alloy phase and Ni in the oxide phase occurs during the sintering process.The samples were also examined as inert anodes for aluminum electrowinning in the low-temperature KF–NaF–AlF_3 molten electrolyte for 24 h.The cell voltage during electrolysis and the corrosion scale on the anodes were analyzed.The results confirm that the scale has a self-repairing function because of the synergistic reaction between the alloy phase with Fe added and the oxide phase.The estimated wear rate of the(Cu_(52)Ni_(30)Fe_(18))–50Ni Fe_2O_4 composite anode is 2.02 cm·a^(-1).

Amylopectin from Glutinous Rice as a Sustainable Binder for High-Performance Silicon Anodes

Silicon(Si)has been investigated as a promising anode material because of its high theoretical capacity(4200 m Ah g^(-1)).However,silicon anode suffers from huge volume changes during repeated charge–discharge cycles.In this work,inspired by a remarkable success of the glutinous rice mortar in the Great Wall with ca.2000-year history,amylopectin(AP),the key ingredient responsible for the strong bonding force,is extracted from glutinous rice and utilized as a flexible,aqueous,and resilient binder to address the most challenging drastic volume-expansion and pulverization issues of silicon anode.Additionally,the removal of toxic N-methyl-2-pyrrolidone(NMP)organic solvent makes the electrode fabrication process environmentally friendly and healthy.The as-prepared Si-AP electrode with 60 wt%of Si can uphold a high discharge capacity of 1517.9 m Ah g^(-1)at a rate of 0.1 C after 100 cycles.The cycling stability of the Si-AP has been remarkably improved in comparison with both traditional polyvinylidene fluoride(PVDF)and aqueous carboxymethylcellulose(CMC)binders.Moreover,when the content of silicon in the Si-AP electrode increases to 70 wt%,a high discharge capacity of 1463.1 m Ah g^(-1)can still be obtained after 50 cycles at 0.1°C.These preliminary results suggest that the sustainably available and environmentally benign amylopectin binders could be a promising choice for the construction of highly stable silicon anodes.

Poly(thiourea triethylene glycol) as a multifunctional binder for enhanced performance in lithium-sulfur batteries

A mechanically strong binder with polar functional groups could overcome the dilemma of the large volume change during charge/discharge processes and poor cyclability of lithium-sulfur batteries(LSBs).In this work,for the first time,we report the use of poly(thiourea triethylene glycol)(PTTG)as a multifunctional binder for sulfur cathodes to enhance the performance of LSBs.As expected,the PTTG binder facilitates the high performance and stability delivered by the Sulfur-PTTG cathode,including a higher reversible capacity of 825 mAh g^(-1) at 0.2 C after 80 cycles,a lower capacity fading(0.123%per cycle)over 350 cycles at 0.5 C,a higher areal capacity of 2.5 mAh cm^(-2) at 0.25 mA cm^(-2),and better rate capability of 587 mAh g^(-1) at 2 C.Such superior electrochemical performances could be attributed to PTTG's strong chemical adsorption towards polysulfides which may avoid the lithium polysulfide shuttle effect and excellent mechanical characteristics which prevents electrode collapse during cycling and allows the Sulfur-PTTG electrode to maintain robust electron and ion migration pathways for accelerated redox reaction kinetics.

Pt-Te alloy nanowires towards formic acid electrooxidation reaction

The high-performance anodic electrocatalysts is pivotal for realizing the commercial application of the direct formic acid fuel cells.In this work,a simple polyethyleneimine-assisted galvanic replacement reaction is applied to synthesize the high-quality PtTe alloy nanowires(PtTe NW)by using Te NW as an efficient sacrificial template.The existence of Te atoms separates the continuous Pt atoms,triggering a direct reaction pathway of formic acid electrooxidation reaction(FAEOR)at PtTe NW.The one-dimensional architecture and highly active sites have enabled PtTe NW to reveal outstanding electrocatalytic activity towards FAEOR with the mass/specific activities of 1091.25 mA mg^(-1)/45.34 A m^(-2)at 0.643 V potential,which are 44.72/23.16 and 20.26/11.75 times bigger than those of the commercial Pt and Pd nanoparticles,respectively.Density functional theory calculations reveal that Te atoms optimize the electronic structure of Pt atoms,which decreases the adsorption capacity of CO intermediate and simultaneously improves the durability of PtTe NW towards FAEOR.This work provides the valuable insights into the synthesis and design of efficient Pt-based alloy FAEOR electrocatalysts.

Construction of Mo/Mo_(2)C@C modified ZnIn_(2)S_(4)Schottky junctions for efficient photo-thermal assisted hydrogen evolution

Photocatalytic water splitting on noble metal-free photocatalysts for H_(2) generation is a promising but challenging approach to realize solar-to-chemical energy conversion.In this study,Mo/Mo_(2)C nanoparticles anchored carbon layer(Mo/Mo_(2)C@C)was obtained by a one-step in-situ phase transition approach and developed for the first time as a photothermal cocatalyst to enhance the activity of ZnIn_(2)S_(4)photocatalyst.Mo/Mo_(2)C@C nanosheet exhibits strong absorption in the full spectrum region and excellent photo-thermal conversion ability,which generates heat to improve the reaction temperature and accelerate the reaction kinetics.Moreover,metallic Mo/Mo_(2)C@C couples with ZnIn_(2)S_(4)to form ZnIn_(2)S_(4)-Mo/Mo_(2)C@C Schottky junction(denoted as ZMM),which prevents the electrons back transfer and restrains the charge recombination.In addition,conductive carbon with strong interfacial interaction serves as a fast charge transport bridge.Consequently,the optimized ZMM-0.2 junction exhibits an H2 evolution rate of 1031.07μmol g^(-1)h^-(1),which is 41 and 4.3 times higher than bare ZnIn_(2)S_(4)and ZnIn_(2)S_(4)-Mo2C,respectively.By designing novel photothermal cocatalysts,our work will provide a new guidance for designing efficient photocatalysts.

Long-term outcomes and prognostic factors for patients with esophageal cancer following radiotherapy

AIM:To evaluate long-term outcomes and prognostic factors for esophageal squamous cell carcinoma(SCC) treated with three dimensional conformal radiotherapy(3D-CRT).METHODS:Between January 2005 and December 2006,153 patients(120 males,33 females) with pathologically confirmed esophageal SCC and treated with 3D-CRT in Cancer Hospital of Shantou University were included in this retrospective analysis.Median age was 60 years(range:37-84 years).The proportion of tumor location was as follows:upper thorax(including the cervical region),73(48%);middle thorax,73(48%);lower thorax,7(5%),respectively.The median radiation dose was 64 Gy(range:50-74 Gy).Fifty four cases(35%) received cisplatin-based concurrent chemotherapy.Univariate and multivariate analysis were performed to determine the association between the correlative factors and prognosis.RESULTS:The five-year overall survival rate was 26.3%,with a median follow-up of 49 mo(range:3-66 mo) for patients who were still alive.On univariate analysis,lesion location,lesion length by barium esophagogram,computed tomography imaging characteristics including Y diameter(anterior-posterior,AP,extent of tumor),gross tumor volume of primary lesion(GTV-E),volume of positive lymph nodes(GTV-LN),and the total target volume(GTV-T = GTV-E + GTVLN) were prognostic for overall survival.By multivariate analysis,only the Y diameter [hazard ratio(HR) 2.219,95%CI 1.141-4.316,P = 0.019] and the GTV-T(HR 1.372,95%CI 1.044-1.803,P = 0.023) were independent prognostic factors for survival.CONCLUSION:The overall survival of esophageal carcinoma patients undergoing 3D-CRT was promising.The best predictors for survival were GTV-T and Y diameter.

COMPOSITIONAL HETEROGENEITY OF ETHYLENE OXIDE-BUTYLENE TEREPHTHALATE SEGMENTED COPOLYMER

A series of ethylene oxide-butylene terephthalate (EOBT) segmented copolymers with different soft segment length and hard segment content were synthesized. The compositional heterogeneity was studied by solvent extraction. The results show that the compositional heterogeneity increases when soft segment length and hard segment content increase. The compositional heterogeneity is also reflected in the crystallization behavior and morphology of soft and hard segment in EOBT segmented copolymer. The more compositional heterogeneous the EOBT segmented copolymer is, the more different the morphology and the crystallization behavior between separated fractions. Compared with ethylene oxide-ethylene terephthalate (EOET) segmented copolymer, compositional heterogeneity in EOBT segmented copolymer is weaker. But the compositional heterogeneity in EOBT segmented copolymer with long soft segment and high hard segment content is still obvious.

Uncovering the synergistic photocatalytic behavior of bimetallic molecular catalysts

Bimetallic catalysts usually exhibit better performance than monometallic catalysts due to synergistic effect.However,there is a lack of exploring the synergistic effect on catalytic performance caused by the introduction of inactive metal ion.In this work,we design a molecular model system that can precisely regulate the metal site number and catalytic property.When these molecular metal compounds are used as homogeneous catalysts for photocatalytic CO_(2)reduction,the dinuclear heterometallic CuNi-L2shows the highest CO_(2)-to-CO conversion,which is 2.1 and 3.0 times higher than that of dinuclear homometallic Ni2-L2and mononuclear Ni-L1.Density functional theory calculations demonstrate that,in CuNi-L2,the introduction of inactive CuⅡis easier to promote the photo-generated electrons transferring to the coupled active NiⅡsite to achieve the highest activity.In addition,this work also provides insights to design and construct more efficient bimetallic catalysts in future.

A 3D Ni_(8)-cluster-based MOF as a molecular electrocatalyst for alcohol oxidation in alkaline media

1.Introduction DAFCs offer significant promise for compact electric devices through the consumption of liquid fuels as one of the renewable energy sources,with minimal environmental effects and prominent energy density[1-4].Because of the fuel crossover phenomenon and sluggish kinetics of the alcohol oxidation.

Recent developments of fluorescence imaging technology in the second near-infrared window

Background:Fluorescence bio-imaging in the second near-infrared window(NIR-II FL,1000-1700nm)has great potential in clinical theranostics,which is of great importance providing precise locations of lesions and molecular dynamic actions simultaneously in a single nanoprobe.Methods:T here has been an upsurge of multidisciplinary research focusing on developing functional types of inorganic and organic nanoprobes that can be used for NIR-II FL with the high spatiotemporal resolution,deep tissue penetration,and negligible auto-fluorescence.Results:In this mini-review,we summarize recent progress in inorganic/organic NIR-II FL nanoprobes.We introduce the design and properties of inorganic and organic nanoprobes,in the order of single-walled carbon nanotubes,quantum dots,rare-earth-doped nanoparticles,metal nanoclusters and organic fluorophores,expect to realize precise diagnosis and efficient image-guided therapy.Conclusion:Meanwhile,to elucidate the problems and perspectives,we aim to offer diverse biological applications of inorganic/organic NIR-II FL nanoprobes and accelerate the clinical transformation progress.

SAIH: A Scalable Evaluation Methodology for Understanding AI Performance Trend on HPC Systems

Novel artificial intelligence(AI)technology has expedited various scientific research,e.g.,cosmology,physics,and bioinformatics,inevitably becoming a significant category of workload on high-performance computing(HPC)systems.Existing AI benchmarks tend to customize well-recognized AI applications,so as to evaluate the AI performance of HPC systems under the predefined problem size,in terms of datasets and AI models.However,driven by novel AI technology,most of AI applications are evolving fast on models and datasets to achieve higher accuracy and be applicable to more scenarios.Due to the lack of scalability on the problem size,static AI benchmarks might be under competent to help understand the performance trend of evolving AI applications on HPC systems,in particular,the scientific AI applications on large-scale systems.In this paper,we propose a scalable evaluation methodology(SAIH)for analyzing the AI performance trend of HPC systems with scaling the problem sizes of customized AI applications.To enable scalability,SAIH builds a set of novel mechanisms for augmenting problem sizes.As the data and model constantly scale,we can investigate the trend and range of AI performance on HPC systems,and further diagnose system bottlenecks.To verify our methodology,we augment a cosmological AI application to evaluate a real HPC system equipped with GPUs as a case study of SAIH.With data and model augment,SAIH can progressively evaluate the AI performance trend of HPC systems,e.g.,increasing from 5.2%to 59.6%of the peak theoretical hardware performance.The evaluation results are analyzed and summarized into insight findings on performance issues.For instance,we find that the AI application constantly consumes the I/O bandwidth of the shared parallel file system during its iteratively training model.If I/O contention exists,the shared parallel file system might become a bottleneck.

Atomically precise metal-chalcogenide semiconductor molecular nanoclusters with high dispersibility:Designed synthesis and intracluster photocarrier dynamics

A comprehensive understanding of excited-state dynamics of semiconductor quantum dots or nanomaterials at the atomic or molecular level is of scientific importance.Pure inorganic(or non-covalently protected)seimiconductor molecular nanoclusters with atomically precise structure are contributive to establish accurate correlation of excited-state dynamics with their composition/structure,however,the related studies are almost blank because of unresolved solvent dispersion issue.Herein,we designedly created the largest discrete chalcogenide seimiconductor molecular nanoclusters(denoted P2-CuMSnS,M=In or/and Ga)with great dispersibility,and revealed an interesting intracluster“core–shell”charge transfer relaxation dynamics.A systematic red shift in absorption spectra with the gradual substitution of In by Ga was experimentally and computationally investigated,and femtosecond transient absorption measurements further manifested there were three ultrafast processes in excited-state dynamics of P2 nanoclusters with the corresponding amplitudes directed by composition variation.Current results hold the great promise of the solution-processible applications of semiconductor-NC-based quantum dots and facilitate the development of atomically precise nano-chemistry.

NONLINEAR GALERKIN METHOD AND CRANK-NICOLSONMETHOD FOR VISCOUS INCOMPRESSIBLE FLOW

In this article we discuss a new full discrete scheme for the numerical solution of the Navier-Stokes equations modeling viscous incompressible flow. This scheme consists of nonlinear Galerkin method using mixed finite elements and Crank-Nicolson method. Next, we provide the second-order convergence accuracy of numerical solution corresponding to this scheme. Compared with the usual Galerkin scheme, this scheme can save a large amount of computational time under the same convergence accuracy. (Author abstract) 8 Refs.

Sustainable engineering of TiO_(2)-based advanced oxidation technologies:From photocatalyst to application devices

In recent years,photocatalysis(PC)and photoelectrocatalysis(PEC)technologies have shown great promise as low-cost,environmentally friendly,and sustainable strategies in addressing the issues of energy shortages and environmental pollution,which has become a research hotspot.Titanium dioxide(TiO_(2))-based PC and PEC are the most promising sustainable technologies for advanced oxidation applications.Due to its inherent characteristics,including high oxidation ability,low price,and stability,TiO_(2)photocatalyst has been widely studied and used in different scales for numerous decades.For practical applications in these areas,the engineering of the photocatalysts and the design of the PC and PEC devices must be both environmentally and economically sustainable.On the one hand,for the engineering of the photocatalysts,the photocatalyst shall be able to deliver the following characteristics,including large specific surface area,high absorption of light,rapid and low-cost separation and regeneration,and high stability.On the other hand,the design of the PC and PEC devices shall facilitate high in energy utilization and catalytic efficiency,and low in building and operational cost.This work covers the reaction mechanism of TiO_(2)-based PC and PEC technologies,sustainable design,and preparation of TiO_(2)photocatalysts as well as sustainable design in PC and PEC devices for wastewater treatment,sensing,and water splitting.Finally,we provide some critical perspectives on the future development of TiO_(2)-based PC and PEC technology.

Uniform Lipschitz Estimates of Homogenization of Elliptic Systems in Divergence Form with Dini Conditions

The paper is devoted to the homogenization of elliptic systems in divergence form.We obtain uniform interior as well as boundary Lipschitz estimates in a bounded C1,γdomain when the coefficients are Dini continuous,inhomogeneous terms are divergence of Dini continuous functions and the boundary functions have Dini continuous derivatives.The results extend Avellaneda and Lin’s work[Comm.Pure Appl.Math.,40:803-847(1987)],where Holder continuity is the main assumption on smoothness of the data.

Anefficient parallel and distributed solution to nonconvex penalized linear SVMs

Support vector machines(SVMs)have been recognized as a powerful tool to perform linear classification.When combined with the sparsity-inducing nonconvex penalty,SVMs can perform classification and variable selection simultaneously.However,the nonconvex penalized SVMs in general cannot be solved globally and efficiently due to their nondifferentiability,nonconvexity,and nonsmoothness.Existing solutions to the nonconvex penalized SVMs typically solve this problem in a serial fashion,which are unable to fully use the parallel computing power of modern multi-core machines.On the other hand,the fact that many real-world data are stored in a distributed manner urgently calls for a parallel and distributed solution to the nonconvex penalized SVMs.To circumvent this challenge,we propose an efficient alternating direction method of multipliers(ADMM)based algorithm that solves the nonconvex penalized SVMs in a parallel and distributed way.We design many useful techniques to decrease the computation and synchronization cost of the proposed parallel algorithm.The time complexity analysis demonstrates the low time complexity of the proposed parallel algorithm.Moreover,the convergence of the parallel algorithm is guaranteed.Experimental evaluations on four LIBSVM benchmark datasets demonstrate the efficiency of the proposed parallel algorithm.

Dynamic recrystallization behavior of Fe–20Cr–30Ni–0.6Nb–2Al–Mo alloy

Single-pass compression tests of an aluminaforming austenite(AFA) alloy(Fe–20Cr–30Ni–0.6Nb–2Al–Mo) were performed using a Gleeble-3500 thermal–mechanical simulator. By combining techniques of electron back-scattered diffraction(EBSD) and transmission electron microscopy(TEM), the dynamic recrystallization(DRX) behavior of the alloy at temperatures of 950–1100 ℃ and strain rates of 0.01–1.00 s^(-1) was investigated. The regression method was adopted to determine the thermal deformation activation energy and apparent stress index and to construct a thermal deformation constitutive model. Results reveal that the flow stress is strongly dependent on temperature and strain rate and it increases with temperature decreasing and strain rate increasing. The DRX phenomenon occurs more easily at comparably higher deformation temperatures and lower strain rates. Based on the method for solving the inflection point via cubic polynomial fitting of strain hardening rate(h) versus strain(e) curves, the ratio of critical strain(ec) to peak strain(ep) during DRX was precisely predicted. The nucleation mechanisms of DRX during thermal deformation mainly include the strain-induced grain boundary(GB)migration, grain fragmentation, and subgrain coalescence.

Breakdown of Valence Shell Electron Pair Repulsion Theory in an H-Bond-Stabilized Linear sp-Hybridized Sulfur

Exploring the unusual orbital hybridization types of atoms and their new connection modes contributes to the development of chemical bond theory and can inspire compounds with unique molecular configurations.Dicoordinated sulfur(S)atoms(or anions)with sp3 hybridization in a bent-bridging mode are commonly observed in many inorganic and organic compounds.However,sp-hybridized S species have,thus far,been extremely rare,and the linearly bridging mode has only been“forcibly”achieved with the aid of metal–S multiple bonds and/or significant steric hindrance from the surrounding organic ligands.