Study on the Performance of the GRANDProto300 Particle Detector Array by Simulation

The Giant Radio Array for Neutrino Detection(GRAND)is a proposed large-scale observatory designed to detect cosmic rays,gamma-rays,and neutrinos with energies exceeding 100 Pe V.The GRANDProto300 experiment is proposed as the early stage of the GRAND project,consisting of a hybrid array of radio antennas and scintillator detectors.The latter,as a mature and traditional detector,is used to cross-check the nature of the candidate events selected from radio observations.In this study,we developed a simulation software called G4GRANDProto300,based on the Geant4 software package,to optimize the spacing of the scintillator detector array and to investigate its effective area.The analysis was conducted at various zenith angles under different detector spacings,including 300,500,600,700,and 900 m.Our results indicate that,for large zenith angles used to search for cosmic-ray in the GRAND project,the optimized effective area is with a detector spacing of 500 m.The G4GRANDProto300 software that we developed could be used to further optimize the layout of the particle detector array in future work.

MiR-450b-5p enhances the radiosensitivity of HR^(+) and HER2^(−) breast cancer by targeting CDK6

Background:The sensitivity of breast cancer cells to radiation is a key cause of locoregional recurrence after postoperative radiotherapy.Several studies have reported that microRNAs(miRNAs)are involved in the radiosensitivity of human breast cancer cells.One miRNA microarray study showed that miR-450b-5p was overexpressed 13.3-fold in patients with estrogen receptor–positive(ER^(+))and human epidermal growth factor receptor 2–negative(HER2−)breast cancer and no local relapse compared with local relapse patients.However,its underlying mechanism of action remains unknown.Methods:The predicted target mRNAs of miR-450b-5p were screened using the TargetScan,miRDB,and miRWalk databases.Western blotting,quantitative polymerase chain reaction,and dual-luciferase reporter assays explored the association between cyclindependent kinase 6(CDK6)and miR-450b-5p.The cell counting kit-8 assay and flow cytometry detected the proliferation of transfected MCF7 cells.Colony formation and xenograft tumors detected the radiosensitivity of the transfected MCF7 cells.Results:Bioinformatics analysis,Western blotting,quantitative polymerase chain reaction,and dual-luciferase reporter assays demonstrated that CDK6 was the target gene of miR-450b-5p.Furthermore,in vitro and in vivo experiments showed that miR-450b-5p inhibited MCF7 cell proliferation and cell cycle progression,increased the sensitizer enhancement ratio,and decreased the volume of xenograft tumors after irradiation by regulating CDK6.Conclusions:This study demonstrates that miR-450b-5p enhances the radiosensitivity of hormone receptor–positive(HR^(+))and HER2−breast cancer cells and elucidates its mechanism.miR-450b-5p may be considered a therapeutic target in HR^(+)and HER2−breast cancer treated with radiotherapy.

Rathke囊肿的诊断及神经内镜手术治疗

目的:提高Rathke囊肿的术前诊断率和总结神经内镜下切除Rathke囊肿的手术技术,并评价其疗效。方法:采用神经内镜经单鼻孔–蝶窦入路切除Rathke囊肿12例。结果:8例全切除、4例次全切除,症状均明显改善,无明显并发症发生,手术耗时较经鼻蝶窦入路显微镜下手术、开颅手术明显缩短。结论:神经内镜下经单鼻孔–蝶窦路径切除Rathke囊肿是一种有效的微侵袭手术方法。

A density functional theory study on the decomposition of aliphatic hydrocarbons and cycloalkanes during coal pyrolysis in hydrogen plasma

To get deep understanding of the reaction mechanism of coal pyrolysis in hydrogen plasma, the decomposition reaction pathways of aliphatic hydrocarbons and cycloalkanes, which are two main components in volatiles from coal, were investigated. Methane and cyclohexane were chosen as the model compounds. Density functional theory was employed, and many reaction pathways were involved. Calculations were carried out in Gaussian 09 at the B3LYP/6-31G（d,p） level of the theory. The results indicate that the main pyrolysis products of methane and cyclohexane in hydrogen plasma are both hydrogen and acetylene, and the participation of active hydrogen atoms makes dehydrogenation reactions more favorable. H2 mainly comes from dehydrogenation process, while many reaction pathways are responsible for acetylene formation. During coal pyrolysis in hydrogen plasma, three main components in volatiles like aliphatic hydrocarbons, cycloalkanes and aromatic hydrocarbons lead to the formation of hydrogen and acetylene, but their contributions to products distribution are different.

Pathways of liquefied petroleum gas pyrolysis in hydrogen plasma:A density functional theory study

A density functional theory （DFT） study has been conducted in this work to investigate the pyrolysis pathways of propane and n-butane, which are the main components of liquefied petroleum gas （LPG）, for better understanding the pyrolysis behavior of LPG in hydrogen thermal plasma. Over 60 possible reactions are considered. The reaction enthalpies and activation energies of these reactions are calculated and analyzed with a Gaussian method of B3LYP and basic set of 6-31G （d,p）. A most possible reaction pathway is brought up. According to this reaction pathway, the main products of LPG pyrolysis are acetylene, ethylene, methane, ethane and extra hydrogen. Acetylene mainly comes from the pyrolysis of propylene and ethylene, and hydrogen abstraction reactions are the main source of extra hydrogen gas. Active H. radicals are found to play a very important role in many reactions, and they can remarkably lower the energies needed for reactions.

Collapse arrest in the space-fractional Schrodinger equation with an optical lattice

The soliton solution and collapse arrest are investigated in the one-dimensional space-fractional Schrodinger equation with Kerr nonlinearity and optical lattice.The approximate analytical soliton solutions are obtained based on the variational approach,which provides reasonable accuracy.Linear-stability analysis shows that all the solitons are linearly stable.No collapses are found when the Levy index 1<α≤2.Forα=1,the collapse is arrested by the lattice potential when the amplitude of perturbations is small enough.It is numerically proved that the energy criterion of collapse suppression in the two-dimensional traditional Schrodinger equation still holds in the one-dimensional fractional Schr odinger equation.The physical mechanism for collapse prohibition is also given.

Constraints on axion-like particles from the observation of Galactic sources by the LHAASO

High-energy photons may oscillate with axion-like particles(ALPs)when they propagate through the Milky Way's magnetic field,resulting in an alteration in the observed photon energy spectrum.Ultra-high energy gamma-ray spectra,measured by the Large High Altitude Air Shower Observatory(LHAASO)up to O(1)PeV,provide a promising opportunity to investigate the ALP-photon oscillation effect.In this study,we utilize the gamma-ray spectra of four Galactic sources measured by the LHAASO,that is,the Crab Nebula,LHAASO J2226+6057,LHAASO J1908+0621,and LHAASO J1825-1326,to explore this effect.We employ the CLsmethod to set constraints on the ALP parameters.Our analysis of the observations of the four sources reveals that the ALPphoton coupling gaγis constrained to be smaller than 1.4×10^(-1)0GeV^(-1)for an ALP mass of~4×10^(-7)eV at 95%C.L.Combining the observations of the Crab Nebula from the LHAASO and other experiments,we find that the ALP-photon coupling may be set to approximately 7.5×10^(-11)GeV^(-1)for an ALP mass of~4×10^(-7)eV,which is similar to the CAST constraint.

“悟空”号的火眼金睛与暗物质线谱搜寻

早在20世纪30年代,瑞士天文学家Fritz Zwicky[1]发现后发星系团中的星系速度弥散过大,由位力定理可知,仅靠星系团中的发光物质无法维持整个系统的稳定.因此他提出在星系团中还存在随后被称为暗物质的某种不发光物质.这一发现开启了人类对暗物质的认识和研究.

Guidelines for burn rehabilitation in China

Quality of life and functional recovery after burn injury is the final goal of burn care,especially as most of burn patients survive the injury due to advanced medical science.However,dysfunction,disfigurement,contractures,psychological problems and other discomforts due to burns and the consequent scars are common,and physical therapy and occupational therapy provide alternative treatments for these problems of burn patients.This guideline,organized by the Chinese Burn Association and Chinese Association of Burn Surgeons aims to emphasize the importance of team work in burn care and provide a brief introduction of the outlines of physical and occupational therapies during burn treatment,which is suitable for the current medical circumstances of China.It can be used as the start of the tools for burn rehabilitation.

SIS Model of Rumor Spreading in Social Network with Time Delay and Nonlinear Functions

With the advent of the information age of networks,the study about rumor propagation in social networks has become increasingly significant.In this paper,a rumor propagation model with nonlinear functions and time delay in social networks is proposed.First,according to the nextgeneration matrix method,we work out the basic reproduction number.Second,we discuss the existence of the rumor-prevailing equilibrium points.Third,we demonstrate the stabilities of equilibrium points and analyze the sufficient conditions for Hopf bifurcation.Finally,the correctness of the theory is verified and several vital conclusions are obtained by numerical simulations.

Extracellular vesicles derived from neural EGFL-Like 1-modified mesenchymal stem cells improve acellular bone regeneration via the miR-25-5p-SMAD2 signaling axis

Stem cell based transplants effectively regenerate tissues;however, limitations such as immune rejection and teratoma formation prevent their application. Extracellular vesicles (EVs)-mediated acellular tissue regeneration is a promising alternative to stem cell based transplants. Although neural EGFL-like 1 (Nell1) is known to contribute to the osteogenic differentiation of bone marrow stem cells (BMSCs), it remains unknown whether EVs are involved in this process. Here, we present that EVs derived from Nell1-modified BMSCs (Nell1/EVs) have a stronger ability to promote BMSC osteogenesis owing to miR-25–5p downregulation. MiR-25–5p inhibits osteogenesis by targeting Smad2 and suppressing the SMAD and extracellular signal-related kinase 1 and 2 (ERK1/2) pathway activation. In addition, we demonstrate that the 3D-Nell1/EV-hydrogel system is beneficial for bone regeneration in vivo, probably stemming from a slow, continuous release and high concentration of EVs in the bone defect area. Thus, our results have shown the potential of Nell1/EVs as a novel acellular bone regeneration strategy. Mechanistically, the identification of miR-25-5p-SMAD2 signaling axis expands the knowledge of Nell1/EVs induced osteogenesis.

A MULTI-OBJECTIVE ROBUST OPERATION MODEL FOR ELECTRONIC MARKET ENABLED SUPPLY CHAIN WITH UNCERTAIN DEMANDS

A multi-objective robust operation model is proposed in this paper for an electronic market enablexi supply chain consisting of multi-supplier and multi-customer with uncertain demands. Suppliers in this supply chain provide many kinds of products to different customers directly or through electronic market. Uncertain demands are described as a scenario set with certain probability;, the supply chain operation model is constructed by using the robust optimization method based on scenario analyses. The operation model we proposed is a multi-objective programming problem satisfying several conflict objectives, such as meeting the demands of all customers, minimizing the system cost, the availabilities of suppliers＇ capacities not below a certain level, and robustness of decision to uncertain demands. The results of numerical examples proved that the solution of the model is most conservative; however, it can ensure the robustness of the operation of the supply chain effectively.

Guideline for diagnosis, prophylaxis and treatment of invasive fungal infection post burn injury in China 2013

Invasive fungal infection is one of the major complication of severe burns which can induce local or systemic inflammatory response and cause serious substantial damage to the patient. The incidence of fungal infection for burn victims is increasing dramatically during recent years. This guideline, organized by Chinese Society of Burn Surgeons, aims to standardize the diagnosis, prevention and treatment of burn invasive fungal infection. It can be used as one of the tools for treatment of major burn patients.

Implications on the origin of cosmic rays in light of 10 TV spectral softenings

Precise measurements of the energy spectra of cosmic rays(CRs)show various kinds of features deviating from single power-laws,which give very interesting and important implications on their origin and propagation.Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons(and probably also for Helium nuclei).Very recently,the DArk Matter Particle Explorer(DAMPE)measurement about the proton spectrum clearly reveals such a softening with a high significance.Here we study the implications of these new measurements,as well as the groundbased indirect measurements,on the origin of CRs.We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously.In the framework of multiple components,we discuss two possible scenarios,the multiple source population scenario and the background plus nearby source scenario.Both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies.Considering the anisotropy observations,the nearby source model is favored.

Correlativity study between expression of DNA double-strand break repair protein and radiosensitivity of tumor cells

DNA double-strand break(DSB)is generally regarded as the most lethal of all DNA lesions after radiation.Ku80,DNA-PK catalytic subunit(DNA-PKcs)and ataxia telangiectasia mutated(ATM)proteins are major DSB repair proteins.In this study,survival fraction at 2Gy(SF2)values of eight human tumor cell lines(including four human cervical carcinoma cell lines HeLa,SiHa,C33A,Caski,three human breast carcinoma cell lines MCF-7,MDA-MB-231,MDA-MB-453,and one human lung carcinoma cell line A549)were acquired by clone formation assay,and western blot was applied to detect the expressions of Ku80,DNA-PKcs and ATM protein.The correlativity of protein expression with SF2 value was analyzed by Pearson linear correlation analysis.We found that the expression of the same protein in different cell lines and the expression of three proteins in the same cell line had a significant difference.The SF2 values were also different in eight tumor cell lines and there was a positive correlativity between the expression of DNA-PKcs and SF2(r=0.723,P=0.043),but Ku80 and ATM expression had no correlation with SF2(P>0.05).Thesefindings suggest that the expression level of DNA-PKcs protein can be an indicator for predicting the radiosensitivity of tumor cells.

Portfolio Robust Optimization Model and Its Application

Classical formulations of the portfolio optimization, such as mean-variance or Value-at-Risk（VaR） approaches, can result in a portfolio extremely sensitive to errors in the date, such as mean and covariance matrix. In this paper we propose a way to alleviate this problem in a tractable manner. We proposed a robust portfolio optimization model, which can be solved by using linear matrix inequalities （LMI） .To substantiate the conclusion we cite an empirical analysis which adopts correlated data from Shanghai Stock Exchange. The result indicates that the robust model of portfolio is efficient and feasible.