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Rotating Massive Strangeon Stars and X-Ray Plateau of Short GRBs

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Research in Astronomy and Astrophysics 2024年第3期24卷 47-57页

作者： xi-yan yang xiao-Yu Lai Wei-Wei Tan Ren-xin Xu School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhou 434023China Research Center for Astronomy Hubei University of EducationWuhan 4300205China Key Laboratory of Quark and Lepton Physics Central China Normal UniversityMinistry of EducationWuhan 430079China School of Physics Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

Strangeon stars,which are proposed to describe the nature of pulsar-like compact stars,have passed various observational tests.The maximum mass of a non-rotating strangeon star could be high,which implies that the remnants of binary strangeon star mergers could even be long-lived massive strangeon stars.We study rigidly rotating strangeon stars in the slowly rotating approximation,using the Lennard-Jones model for the equation of state.Rotation can significantly increase the maximum mass of strangeon stars with unchanged baryon numbers,enlarging the mass-range of long-lived strangeon stars.During spin-down after merger,the decrease of radius of the remnant will lead to the release of gravitational energy.Taking into account the efficiency of converting the gravitational energy luminosity to the observed X-ray luminosity,we find that the gravitational energy could provide an alternative energy source for the plateau emission of X-ray afterglow.The fitting results of X-ray plateau emission of some short gamma-ray bursts suggest that the magnetic dipole field strength of the remnants can be much smaller than that of expected when the plateau emission is powered only by spin-down luminosity of magnetars.

关键词： dense matter-(stars) pulsars general-(stars) gamma-ray burst general

Parotid metastasis of rare lung adenocarcinoma:A case report

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World Journal of Clinical Cases 2024年第6期12卷 1182-1189页

作者： Ru-xi yan Lin-Bo Dou Zi-Jia Wang Xue Qiao Hong-Hai Ji yan-Cong Zhang School of Stomatology Weifang Medical UniversityWeifang 261000Shandong ProvinceChina Department of Stomatology Dezhou People’s HospitalDezhou 253000Shandong ProvinceChina Department of Stomatology Dezhou Women and Children's HospitalDezhou 253000Shandong ProvinceChina

BACKGROUND Lung cancer(LC)is the leading cause of malignancy-related deaths worldwide.The most common sites of metastasis include the nervous system,bone,liver,respiratory system,and adrenal glands.LC metastasis in the parotid gland is very rare,and its diagnosis presents a challenge.Here,we report a case of parotid metastasis in primary LC.CASE SUMMARY The patient was a 74-year-old male who was discovered to have bilateral facial asymmetry inadvertently two years ago.The right earlobe was slightly swollen and without pain or numbness.Computed tomography(CT)examination showed bilateral lung space-occupying lesions.Pulmonary biopsy was performed and revealed adenocarcinoma(right-upper-lung nodule tissue).Positron emission tomography-CT examination showed:(1)Two hypermetabolic nodules in the right upper lobe of the lung,enlarged hy-permetabolic lymph nodes in the right hilar and mediastinum,and malignant space-occupying lesion in the right upper lobe of the lung and possible metastasis to the right hilar and mediastinal lymph nodes;and(2)multiple hypermetabolic nodules in bilateral parotid glands.Parotid puncture biopsy was performed considering lung adenocarcinoma metastasis.Gene detection of lung biopsy specimens revealed an EGFR gene 21 exon L858R mutation.CONCLUSION This case report highlights the challenging diagnosis of parotid metastasis in LC given its rare nature.Such lesions should be differentiated from primary tumors of the parotid gland.Simple radiological imaging is unreliable,and puncture biopsy is needed for final diagnosis of this condition.

关键词： Lung cancer Metastasis Parotid gland Pathology Positron emission tomography/computed tomography Case report

Acupuncture and moxibustion for irritable bowel syndrome:An umbrella systematic review

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Journal of Integrative Medicine 2024年第1期22卷 22-31页

作者： Yue-ying Ma Zhou Hao Zi-yi Chen yan-xi Shen Hui-rong Liu Huan-gan Wu Chun-hui Bao Shanghai Clinical Research Centre for Acupuncture and Moxibustion Yueyang Hospital of Integrated Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Key Laboratory of Acupuncture and Immunological Effects Shanghai University of Traditional Chinese MedicineShanghai 200030China

BackgroundIrritable bowel syndrome(IBS)is a functional bowel disease characterized by abdominal pain or discomfort associated with altered bowel habits.Several clinical studies have demonstrated the effectiveness of acupuncture and moxibustion for IBS.Many systematic reviews of acupuncture and moxibustion for IBS have been published in recent years,but their results are not entirely consistent.ObjectiveTo evaluate the methodological,reporting,and evidence quality of systematic reviews of acupuncture and moxibustion for IBS.Search strategySystematic reviews of acupuncture and moxibustion for IBS published before February 20,2023 were searched in eight databases:PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Infrastructure,Wanfang Data,VIP Database for Chinese Technical Periodicals,and China Biology Medicine.The keywords used for literature search were acupuncture,moxibustion,systematic review,meta-analysis,and irritable bowel syndrome.Inclusion criteriaSystematic reviews and meta-analyses of randomized controlled trials of acupuncture and moxibustion for IBS were included.Data extraction and analysisRelevant information was independently extracted by two investigators.The A MeaSurement Tool to Assess systematic Reviews 2(AMSTAR 2),Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA 2020),and Grading of Recommendations Assessment,Development and Evaluation(GRADE)were used to evaluate the methodological quality,reporting quality and evidence quality,respectively.ResultsA total of 342 studies were retrieved and 15 systematic reviews were included.The results of AMSTAR 2 showed low methodological quality in 2 studies and very low methodological quality in the remaining 13 studies,with main issues being failure to register a protocol,incomplete search strategy,not providing a list of excluded studies,incomplete consideration of the risk of bias in the included studies,and a failure to assess the publication bias.The results of PRISMA 2020 showed seriously deficient reportin

关键词： Irritable bowel syndrome Acupuncture Moxibustion Umbrella systematic review Systematic review

Highly enhanced thermoelectric and mechanical performance of copper sulfides via natural mineral in-situ phase separation

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Journal of Advanced Ceramics 2024年第5期13卷 641-651页

作者： xi yan Hongjiang Pan Yixin Zhang Tianyu yang yangwei Wang Kun Huang Chongyu Wang Jing Feng Zhenhua Ge Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

In situ phase separation precipitates play an important role in enhancing the thermoelectric properties of copper sulfides by suppressing phonon transmission.In this study,Cu1.8S composites were fabricated by melting reactions and spark plasma sintering.The complex structures,namely,micron-PbS,Sb_(2)S_(3),nano-FeS,and multiscale pores,originate from the introduction of FePb_(4)Sb_(6)S_(14)into the Cu1.8S matrix.Using effective element(Fe)doping and multiscale precipitates,the Cu_(1.8)S+0.5 wt%FePb_(4)Sb_(6)S_(14)bulk composite reached a high dimensionless figure of merit(ZT)value of 1.1 at 773 K.Furthermore,the modulus obtained for this sample was approximately 40.27 GPa,which was higher than that of the pristine sample.This study provides a novel strategy for realizing heterovalent doping while forming various precipitates via in situ phase separation by natural minerals,which has been proven to be effective in improving the thermoelectric and mechanical performance of copper sulfides and is worth promoting in other thermoelectric systems.

关键词： in situ precipitates jamesonite natural mineral thermoelectric copper sulfides

Optimal slag content for geopolymer composites under freeze-thaw cycles with different freezing temperatures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第4期24卷 366-376页

作者： Lifeng FAN Weiliang ZHONG Guang WANG yan xi Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

Improving the freeze-thaw resistance of geopolymers is of great significance to ensure their durability in cold regions. This study presents an experimental investigation of optimal slag content for geopolymer composites under freeze-thaw cycles with different freezing temperatures. Firstly, five kinds of geopolymer composites with 10.0%, 20.0%, 30.0%, 40.0%,and 50.0% slag contents and 1.0% fiber content were prepared. Freeze-thaw cycle tests at-1.0 ℃,-20.0 ℃, and-40.0 ℃ were carried out for these geopolymer composites and their physical and mechanical properties after the freeze-thaw cycle were tested. The results show that the porosity of the geopolymer composites decreases as the slag content increases. Their mass loss ratio and strength loss ratio increase gradually as the freezing temperature decreases. The mass loss ratio and strength loss ratio of geopolymer composites after freeze-thaw cycles all decrease as the slag content increases. Considering the physical and mechanical properties of geopolymers after freeze-thaw cycles, the optimal slag contents are 40.0% and 50.0%.

关键词： Geopolymer composites Freeze-thaw cycle Freezing temperature Slag content

Investigation of three different cooling treatments on dynamic mechanical properties and fragmentation characteristics of granite subjected to thermal cycling

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Underground Space 2022年第5期7卷 847-861页

作者： Lifeng Fan Han Li yan xi Beijing University of Technology Beijing 100124China

Underground thermal engineering such as geothermal exploitation usually involves the response of impact loads due to the drilling operation and blasting load.This study investigated the dynamic mechanical properties and fragmentation characteristics of granite subjected to thermal cycling under natural cooling,water cooling,and liquid nitrogen cooling.Firstly,split Hopkinson pressure bar tests were performed on granite under three different cooling methods to study the dynamic mechanical parameters with thermal cycles.Subsequently,the damage factors were calculated to evaluate the damage on granite and the relationship between damage and stress.Finally,the granite fragments after impact were sieved,and the fractal dimension and average fragment size were introduced to analyze the fragmentation characteristics.The results demonstrate that the degradation of dynamic mechanical properties mainly occurs in the first four thermal cycles;with the increase of damage factor,the stress decreases linearly under the three cooling methods,and the damage caused by liquid nitrogen cooling to granite is the most significant,followed by water cooling.Fragments of granite change from axial splitting failure to a more complex composite failure mode.In addition,with the decrease of the average fragment size,the fractal dimension of the granite gradually increases,resulting in the higher fragmentation degree and the better uniformity of fragmentation.

关键词： Split Hopkinson pressure bar Dynamic mechanical properties Fragmentation characteristics Cooling treatment

DI-3-n-butylphthalide exerts neuroprotective effects by modulating hypoxia-inducible factor 1-alpha ubiquitination to attenuate oxidative stress-induced apoptosis

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Neural Regeneration Research 2023年第11期18卷 2424-2428页

作者： Shuai Li Jingyuan Zhao yan xi Jiaqi Ren yanna Zhu yan Lu Deshi Dong Department of Pharmacy The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Regenerative Medicine Center The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Department of Cardiology Institute of Cardiovascular DiseasesThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina

DI-3-n-butylphthalide is used to treat mild and moderate acute ischemic stroke.However,the precise underlying mechanism requires further investigation.In this study,we investigated the molecular mechanism of DI-3-n-butylphthalide action by various means.We used hydrogen peroxide to induce injury to PC12cells and RAW264.7 cells to mimic neuronal oxidative stress injury in stroke in vitro and examined the effects of DI-3-n-butylphthalide.We found that DI-3-nbutylphthalide pretreatment markedly inhibited the reduction in viability and reactive oxygen species production in PC12 cells caused by hydrogen peroxide and inhibited cell apoptosis.Furthermore,DI-3-n-butylphthalide pretreatment inhibited the expression of the pro-apoptotic genes Bax and Bnip3.DI-3-nbutylphthalide also promoted ubiquitination and degradation of hypoxia inducible factor 1α,the key transcription factor that regulates Bax and Bnip3 genes.These findings suggest that DI-3-n-butylphthalide exhibits a neuroprotective effect on stroke by promoting hypoxia inducible factor-1α ubiquitination and degradation and inhibiting cell apoptosis.

关键词： blood-brain barrier Dl-3-n-butylphthalide hypoxia inducible factor 1α mitochondria neuroprotection oxidative stress reactive oxygen species stroke transcription factor ubiquitination

Application of mesenchymal stem cell therapy for premature ovarian insufficiency: Recent advances from mechanisms to therapeutics

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World Journal of Stem Cells 2024年第1期16卷 1-6页

作者： Hang-Qi Hu xi-yan xin Yu-Tian Zhu Rui-Wen Fan Hao-Lin Zhang yang Ye Dong Li Department of Traditional Chinese Medicine Peking University Third HospitalBeijing 100191China

The incidence of premature ovarian insufficiency(POI)is increasing worldwide,particularly among younger women,posing a significant challenge to fertility.In addition to menopausal symptoms,POI leads to several complications that profoundly affect female reproductive function and overall health.Unfortunately,current clinical treatment strategies for this condition are limited and often yield unsatisfactory outcomes.These approaches typically involve hormone repla-cement therapy combined with psychological support.Recently,mesenchymal stem cell(MSC)therapies for POI have garnered considerable attention in global research.MSCs can restore ovarian reproductive and endocrine functions through diverse mechanisms,including controlling differentiation,promoting angiogenesis,regulating ovarian fibrosis,inhibiting apoptosis,enhancing autocrine and paracrine effects,suppressing inflammation,modulating the immune system,and genetic regulation.This editorial offers a succinct summary of the application of MSC therapy in the context of POI,providing evidence for groundbreaking medical approaches that have potential to enhance reproductive health and overall well-being for women.

关键词： Mesenchymal stem cell therapy Mechanism Premature ovarian insufficiency Therapeutic Women

Spatially distributed damage in sandstone under stress-freeze-thaw coupling conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1910-1922页

作者： Lifeng Fan Yiding Fan yan xi Jingwei Gao College of Architecture and Civil Engineering Beijing University of TechnologyBeijing100124China

In the present study,we tried to understand the spatially distributed damage in sandstone samples under the coupled stress-freeze-thaw(SFT)conditions.Firstly,uniaxial compressive stresses(i.e.0 MPa,10 MPa,20 MPa,and 25 MPa)were applied to the samples,and then freeze-thaw(FT)cycles(0,8,16,and 24)were performed on the uniaxially stressed samples to realize the SFT coupling.Next,real-time CT scanning was conducted to observe the induced damage.The total porosity was introduced to quantitatively evaluate the damage degree.The local porosity variation,with the distance from the center of the sandstone sample,was analyzed to understand the spatial distribution of damage.Finally,the coupling effects of SFT on the damage gradient were discussed.The results indicate that the porosity rises with FT cycles,and the applied stresses can accelerate the increase in porosity.The damage increases exponentially with the distance from the center of the sample.The damage presents a spatial gradient distribution,not the commonly used uniform distribution in various studies.The damage gradient increases with FT cycles,and the increasing rate in damage gradient decreases at uniaxial stress of 0 MPa and 10 MPa first,but the increasing rate in damage gradient increases with FT cycles then at stress increasing to 20 MPa.

关键词： Rock damage Freeze-thaw(FT)cycles Uniaxial stress oupling effects