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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI Bao-ping FAN Hong-yan WANG Guan-nan RAO Xi GE weifeng SHAO xiao-yan LIU Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

Reconfigurable mechanism-based metamaterials for ternary-coded elastic wave polarizers and programmable refraction control

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1225-1242页

作者： Zhou HU Zhibo wei yan CHEN Rui ZHU School of Aerospace Engineering Beijing Institute of Technology School of Mechanical Engineering Tianjin University Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University

Elastic metamaterials with unusual elastic properties offer unprecedented ways to modulate the polarization and propagation of elastic waves. However, most of them rely on the resonant structural components, and thus are frequency-dependent and unchangeable. Here, we present a reconfigurable 2D mechanism-based metamaterial which possesses transformable and frequency-independent elastic properties. Based on the proposed mechanism-based metamaterial, interesting functionalities, such as ternarycoded elastic wave polarizer and programmable refraction, are demonstrated. Particularly, unique ternary-coded polarizers, with 1-trit polarization filtering and 2-trit polarization separating of longitudinal and transverse waves, are first achieved. Then, the strong anisotropy of the proposed metamaterial is harnessed to realize positive-negative bi-refraction, only-positive refraction, and only-negative refraction. Finally, the wave functions with detailed microstructures are numerically verified.

关键词： elastic metamaterial elastic wave reconfigurable design zero mode ternary code programmable refraction O343 74J05

Clinical features of multiple myeloma invasion of the central nervous system in Chinese patients

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Chinese Medical Journal 2010年第11期123卷 1402-1406页

作者： QU xiao-yan FU wei-jun XI Hao ZHOU Fan wei wei HOU Jian Department of Hematology Changzheng Hospital Second Hospital Affiliated to the Second Military Medical University Shanghai 200003 China

Background Although neurologic manifestations often complicate the course of patients with multiple myeloma, direct central nervous system invasion is rare. This study explored the neurologic symptoms, signs, clinical features, therapy and prognosis of Chinese patients with central nervous system myeloma invasion. Methods The diagnosis, therapy and prognosis were analyzed retrospectively in 11 Chinese multiple myeloma patients with central nervous system infiltration from a total of 625 patients who have been treated at Changzheng Hospital （Shanghai, China） between January 1993 and May 2009. Survival curve was constructed with the use of Kaplan-Meier estimates. Results There were 11 patients with central nervous system involvement from 625 multiple myeloma patients. The occurrence rate was 1.8%. Ten of the 11 patients had other extramedullary diseases. Symptoms included cerebral symptoms, cranial nerve palsies, and spinal cord or spinal nerve roots symptoms. Cerebrospinal fluid was abnormal in 7 patients, usually exhibiting pleocytosis and elevated protein content, plus positive cytologic findings. Specific magnetic resonance imaging findings suggestive of central nervous system invasion were found in 9 patients. After a median follow-up of 19 months, 3 patients were alive. The median overall survival for all patients was 23 months, while the median overall survival for patients after central nervous system invasion was merely 6 months. Conclusions It is exceedingly rare for there to be central nervous system infiltration in multiple myeloma patients. When it occurs, the prognosis is extremely poor despite the use of aggressive local and systemic treatment including stem cell transplantation.

关键词： multiple myeloma central nervous system, clinical features therapy, prognosis

Geochronological and geochemical constraints on the petrogenesis and geodynamic process of Hemler,Vlinder,and Il'ichev seamount lavas in NW Pacific

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Science China Earth Sciences 2024年第6期67卷 1856-1871页

作者： Xun wei yan ZHANG Xuefa SHI Hui ZHANG Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China Shandong Key Laboratory of Deep Sea Mineral Resources Development(Preparatory) Qingdao 266061China

Oceanic intraplate volcanoes with linear age progressions are usually accepted to be derived from melting of an upwelling mantle *** seamount groups in NW Pacific,however,show complex age-distance relationships that are difficult to explain using the classic“mantle plume hypothesis”,and thus their origins are *** this study,we present ^(40)Ar-^(39)Ar age,geochemical,and Sr-Nd-Pb-Hf isotopic data of lavas from Hemler,Vlinder,and Il’ichev seamounts in NW Pacific,to elucidate their petrogenesis and geodynamic *** lavas from Hemler,Vlinder,and Il’ichev seamounts are classified as alkali basalt,basanite/nephelinite,and *** with Mg O>8 wt.%exhibit high contents of CaO,FeO^(T),and TiO_(2),similar to the composition of melts formed from reaction between carbonated eclogite-derived melts and fertile *** lavas have elevated Zr/Hf ratios(40.6-45.2)and negative Zr and Hf anomalies,indicating the presence of a carbonate component in the mantle *** are enriched in incompatible trace elements and have enriched mantle 1(EM1)-like SrNd-Pb-Hf isotopic *** isotopic compositions of Vlinder,Il’ichev basanite,and Hemler lavas in this study are similar to the Rarotonga *** occurring at the same seamount,the Il’ichev alkali basalts display more depleted SrNd-Hf isotopic compositions compared to Il’ichev *** to plate tectonic reconstruction results,the ages of Hemler(100.1 Ma),Vlinder pre-(100.2 Ma)and post-shield(87.5 Ma),and Il’ichev(56.4 Ma)lavas clearly deviate from the Macdonald,Arago,Rarotonga,and Samoa hotspot tracks,indicating that they cannot directly originate from mantle *** propose that in the mid-Cretaceous,when the Pacific plate passed over Rarotonga hotspot,melting of Rarotonga plume formed the Vlinder(main-shield stage),Pako,and Ioah *** Rarotonga(and possibly Samoa)plume materials would have been dispersed into the surrounding asthenosphere by mantle conve

关键词： Mantle plume Magellan seamount trail Carbonated mantle component Hotspot Lithosphere extension

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Therapeutic effect of manual massage on early postpartum rectus abdominis separation and postpartum depression

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World Journal of Psychiatry 2024年第5期14卷 678-685页

作者： Yun Chen xiao-yan Sun Cheng Qian xiao-Xing Zhang Yin-Jian Zhou Hong-Yun Zhang Zhen-wei Xie Department of Gynecology Women’s Hospital School of Medicine Zhejiang UniversityHangzhou 310006Zhejiang ProvinceChina Department of Obstetrics and Gynecology Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina Department of Surgery Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina Department of Obstetrics Huzhou Maternity and Child Health Care HospitalHuzhou 313000Zhejiang ProvinceChina Department of Ultrasound Women’s Hospital School of Medicine Zhejiang UniversityHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Rectus abdominis separation(DRA)affects pelvic stability and body *** studies have explored the effects of manual massage on early postpartum DRA and postpartum *** To analyze the curative effect of massage on early postpartum DRA and its impact on postpartum depression and thus its ability promote the overall psychosomatic rehabilitation of postpartum *** Data were retrospectively collected on 70 primiparous women with postpartum DRA who underwent rehabilitation at the Postpartum Rehabilitation Center of Huzhou Maternal and Child Health Hospital from October 2022 to September *** patients were divided into the Group S(35 cases,biomimetic electrical stimulation treatment)and Group L(35 cases,biomimetic electrical stimulation combined with manual massage treatment).Baseline data,the edinburgh postpartum depression scale(EPDS)score,and the visual analog scale(VAS)scores for rectus abdominis distance,waist circumference,and lower back pain before and after treatment were *** No significant differences were found in the baseline data,rectus abdominis distance,waist circumference,and VAS and EPDS scores between the two groups before treatment(P>0.05).After treatment,the distance between rectus abdominis and waist circumference in Group L were significantly smaller than those in Group S(P<0.05).Furthermore,lower back pain(VAS score)and the EPDS score in Group L were significantly lower than those in Group S(P<0.05).CONCLUSION Manual massage can significantly reduce early postpartum DRA,waist circumference,and back pain and improve the patient’s mental state and postpartum depression.

关键词： Manual massage Postpartum Rectus abdominis muscle separation Postpartum depression

Demyelinating neuropathy in patients with hepatitis B virus: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1766-1771页

作者： xiao-xiao yan Jin Huang Jing Lin Department of Neurology The Third Affiliated Hospital of Wenzhou Medical UniversityRuian 325000Zhejiang ProvinceChina

BACKGROUND Hepatitis B rarely leads to demyelinating neuropathy,despite peripheral neuropathy being the first symptom of hepatitis B *** SUMMARY A 64-year-old man presented with sensorimotor symptoms in multiple peripheral *** testing showed that these symptoms were due to hepatitis *** undergoing treatment involving intravenous immunoglobulin and an antiviral agent,there was a notable improvement in his *** Although hepatitis B virus(HBV)infection is known to affect hepatocytes,it is crucial to recognize the range of additional manifestations linked to this *** connection between long-term HBV infection and demyelinating neuropathy has seldom been documented;hence,prompt diagnostic and treatment are *** patient's positive reaction to immunoglobulin seems to be associated with production of the antigen-antibody immune complex.

关键词： Hepatitis B virus infection Extrahepatic manifestations Demyelinating neuropathy Intravenous immunoglobulin Electroneuromyography Case report

Quantitative Analysis of Seeing with Height and Time at Muztagh-Ata Site Based on ERA5 Database

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Research in Astronomy and Astrophysics 2024年第1期24卷 87-95页

作者： xiao-Qi Wu Cun-Ying xiao Ali Esamdin Jing Xu Ze-wei Wang Luo xiao Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Beijing Normal UniversityBeijing 100875China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Seeing is an important index to evaluate the quality of an astronomical *** estimate seeing at the Muztagh-Ata site with height and time quantitatively,the European Centre for Medium-Range Weather Forecasts reanalysis database(ERA5)is *** calculated from ERA5 is compared consistently with the Differential Image Motion Monitor seeing at the height of 12 *** show that seeing decays exponentially with height at the Muztagh-Ata *** decays the fastest in fall in 2021 and most slowly with height in *** seeing condition is better in fall than in *** median value of seeing at 12 m is 0.89 arcsec,the maximum value is1.21 arcsec in August and the minimum is 0.66 arcsec in *** median value of seeing at 12 m is 0.72arcsec in the nighttime and 1.08 arcsec in the *** is a combination of annual and about biannual variations with the same phase as temperature and wind speed indicating that seeing variation with time is influenced by temperature and wind *** Richardson number Ri is used to analyze the atmospheric stability and the variations of seeing are consistent with Ri between *** quantitative results can provide an important reference for a telescopic observation strategy.

关键词： site testing atmospheric effects methods:data analysis telescopes Earth

Iodine Nutrition, Thyroid-stimulating Hormone, and Related Factors of Postpartum Women from three Different Areas in China: A Cross-sectional Survey

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Biomedical and Environmental Sciences 2024年第3期37卷 254-265页

作者： SHAN xiao Yun ZOU yan HUANG Li Chun JIANG Shan ZHOU wei Wen QIN Qiu Lan LIU Chang Qing LUO xiao yan LU Jia Xi MAO De Qian LI Min yanG Zhen Yu yanG Li Chen Key Laboratory of Trace Element Nutrition of National Health Committee National Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China Hunan Key Laboratory of Typical Environmental Pollution and Health Hazards School of Public HealthHengyang Medical SchoolUniversity of South ChinaHengyang 241001HunanChina Zhejiang Provincial Center for Disease Prevention and Control Hangzhou 310051ZhejiangChina Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention Nanning 530028GuangxiChina Hebei Provincial Center for Disease Control and Prevention Shijiazhuang 050021HebeiChina

Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are *** study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum *** A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this *** urinary iodine concentration(UIC),TSH,VA,and VD were *** The median UIC of total and lactating participants were 142.00µg/L and 139.95µg/L,*** median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44μg/mL,and 24.04 ng/mL,*** differences in the UIC were found between lactating and non-lactating *** and TSH levels were significantly different among the three *** rural UIC was higher than the urban *** mothers had a higher UIC and a higher prevalence of excessive *** UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient *** adjustment,no linear correlation was observed between UIC and VA/*** interaction was found between vitamins A/D and UIC on TSH *** The mothers in the present study had no iodine ***,area type,BMI,and VD may be related to the iodine status or TSH levels.

关键词： Median urinary iodine concentration Thyroid-stimulating hormone Vitamin A Vitamin D Postpartum women

Effect of oxide inclusions on MnS precipitates and tensile mechanical property of high-strength low-alloy steel

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1210-1220页

作者： xiao-yong Gao Hong wei Li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Materials Science and Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

The key role of oxide inclusions on the microstructure and mechanical property of a high-strength low-alloy steel was *** field emission scanning electron microscope equipped with energy-dispersive spectrometry was used to characterize MnS *** inclusions play an important role in the shape control of MnS *** oxides fovored to decrease the size and the aspect ratio of MnS *** less oxide inclusions in the steel,approximately over 16.7%MnS precipitates were with aspect ratio a>5 and pure MnS precipitates accounted for 75.9%in ***,with more oxide inclusions in the steel,only 7.4%MnS precipitates were with a>5 and pure MnS precipitates accounted for 60.1%in *** of MnS by oxide inclusions improved the strength and inhibited the *** oxide inclusions in the steel increased the yield strength and tensile strength of the steel in both longitudinal and transverse directions,and lowered the anisotropy of the mechanical property.

关键词： High-strength low-alloy steel MnS Oxide inclusion Mechanical property Anisotropy

Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro

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World Journal of Stem Cells 2024年第2期16卷 163-175页

作者： yan Ren yan-Ni Cui Hong-wei Wang The Second Clinical Medical College Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology The Second Hospital of Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina Department of Hematology Key Laboratory of Molecular Diagnosis and Treatment of Blood Diseases in Shanxi ProvinceTaiyuan 030001Shanxi ProvinceChina

BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital ***(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet *** a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and ***,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or *** propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of *** To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and *** CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental *** cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured ***-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant ***-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead *** Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all P<0.05).The ST-HSCs ratio and fold expansion of the 5 mmol/L NAM group were significantly

关键词： Hematopoietic stem cells Nicotinamide Concentration Proliferation Differentiation Sirtuin 1