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Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model
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作者 Yong-Xiong Zhang Wen-Xiu Guo +4 位作者 Xiao-Ping Lu Hua Zheng Hai-Bin Zhao jun tian Wei-Lin Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期271-286,共16页
Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally intensive.This paper presents a new approach that combines a simplified Celli... Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally intensive.This paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate inversion.The PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore CPUs.The PDE algorithm accurately derives period and pole values from simulated data.The analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole orientations.The PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data analysis.This work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks. 展开更多
关键词 methods:numerical minor planets asteroids:general techniques:photometric astrom
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Clinical pathological characteristics of“crawling-type”gastric adenocarcinoma cancer:A case report
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作者 Yong-Wei Xu Yan Song +3 位作者 jun tian Ba-Cui Zhang Yu-Sheng Yang Jing Wang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1660-1667,共8页
BACKGROUND Gastric cancer(GC)is a significant health problem worldwide,and early detection and accurate diagnosis are crucial for improving patient outcomes.Crawling-type gastric adenocarcinoma is a rare subtype of GC... BACKGROUND Gastric cancer(GC)is a significant health problem worldwide,and early detection and accurate diagnosis are crucial for improving patient outcomes.Crawling-type gastric adenocarcinoma is a rare subtype of GC that has unique histopathological and clinical characteristics,and its diagnosis and management can be challenging.This pathological type of GC is also rare.CASE SUMMARY Here,we report the case of a patient who underwent ordinary endoscopy,na-rrow-band imaging,and endoscopic ultrasonography intending to determine the extent of tumor invasion and upper abdominal enhanced computed tomography and whether there was tumor metastasis.Then,endoscopic submucosal dissection was performed.After pathological and immunohistochemical examination,the pathological diagnosis was crawling-type gastric adenocarcinoma.This is a very rare and special pathological type of tumor.This case highlights the importance of using advanced endoscopic techniques and pathological examination in diagnosing and managing gastric crawling-type adenocarcinoma.Moreover,the findings underscore the need for continued research and clinical experience in this rare subtype of GC to improve patient outcomes.CONCLUSION The“crawling-type”GC is a rare and specific tumor pathology.It is difficult to identify and diagnose gliomas via endoscopy.The tumor is ill-defined,with a flat appearance and indistinct borders due to the lack of contrast against the background mucosa.Pathology revealed that the tumor cells were hand-like,so the patient has diagnosed with“crawling-type”gastric adenocarcinoma. 展开更多
关键词 CLINICOPATHOLOGICAL Crawling-type gastric Pathology Gastric cancer Gastric adenocarcinoma cancer Case report
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CNN-LSTM based incremental attention mechanism enabled phase-space reconstruction for chaotic time series prediction
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作者 Xiao-Qian Lu jun tian +2 位作者 Qiang Liao Zheng-Wu Xu Lu Gan 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期77-90,共14页
To improve the prediction accuracy of chaotic time series and reconstruct a more reasonable phase space structure of the prediction network,we propose a convolutional neural network-long short-term memory(CNN-LSTM)pre... To improve the prediction accuracy of chaotic time series and reconstruct a more reasonable phase space structure of the prediction network,we propose a convolutional neural network-long short-term memory(CNN-LSTM)prediction model based on the incremental attention mechanism.Firstly,a traversal search is conducted through the traversal layer for finite parameters in the phase space.Then,an incremental attention layer is utilized for parameter judgment based on the dimension weight criteria(DWC).The phase space parameters that best meet DWC are selected and fed into the input layer.Finally,the constructed CNN-LSTM network extracts spatio-temporal features and provides the final prediction results.The model is verified using Logistic,Lorenz,and sunspot chaotic time series,and the performance is compared from the two dimensions of prediction accuracy and network phase space structure.Additionally,the CNN-LSTM network based on incremental attention is compared with long short-term memory(LSTM),convolutional neural network(CNN),recurrent neural network(RNN),and support vector regression(SVR)for prediction accuracy.The experiment results indicate that the proposed composite network model possesses enhanced capability in extracting temporal features and achieves higher prediction accuracy.Also,the algorithm to estimate the phase space parameter is compared with the traditional CAO,false nearest neighbor,and C-C,three typical methods for determining the chaotic phase space parameters.The experiments reveal that the phase space parameter estimation algorithm based on the incremental attention mechanism is superior in prediction accuracy compared with the traditional phase space reconstruction method in five networks,including CNN-LSTM,LSTM,CNN,RNN,and SVR. 展开更多
关键词 Chaotic time series Incremental attention mechanism Phase-space reconstruction
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Metabolic syndrome’s new therapy:Supplement the gut microbiome
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作者 Yong-Wei Xu jun tian +2 位作者 Yan Song Ba-Cui Zhang Jing Wang 《World Journal of Diabetes》 SCIE 2024年第4期793-796,共4页
This letter to the editor discusses the publication on gut microbiome supple-mentation as therapy for metabolic syndrome.Gut microbiome dysbiosis disrupts intestinal bacterial homeostasis and is related to chronic inf... This letter to the editor discusses the publication on gut microbiome supple-mentation as therapy for metabolic syndrome.Gut microbiome dysbiosis disrupts intestinal bacterial homeostasis and is related to chronic inflammation,insulin resistance,cardiovascular diseases,type 2 diabetes mellitus,and obesity.Previous research has found that increasing the abundance of beneficial microbiota in the gut modulates metabolic syndrome by reducing chronic inflammation and insulin resistance.Prebiotics,probiotics,synbiotics,and postbiotics are often used as supplements to increase the number of beneficial microbes and thus the produc-tion of short-chain fatty acids,which have positive effects on the gut microbiome and metabolic syndrome.In this review article,the author summarizes the available supplements to increase the abundance of beneficial gut microbiota and reduce the abundance of harmful microbiota in patients with metabolic disorders.Our group is also researching the role of the gut microbiota in chronic liver disease.This article will be of great help to our research.At the end of the letter,the mechanism of the gut microbiota in chronic liver disease is discussed. 展开更多
关键词 Gut microbiome Metabolic syndrome Diabetes mellitus Short-chain fatty acids Chronic liver disease
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Enhanced strength-ductility synergy in a wire and arc additively manufactured Mg alloy via tuning interlayer dwell time 被引量:1
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作者 Dong Ma Chunjie Xu +6 位作者 Shang Sui jun tian Can Guo Xiangquan Wu Zhongming Zhang Dan Shechtman Sergei Remennik 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4696-4709,共14页
Strength-ductility trade-off is a common issue in Mg alloys. This work proposed that a synergistic enhancement of strength and ductility could be achieved through tuning interlayer dwell time(IDT) in the wire and arc ... Strength-ductility trade-off is a common issue in Mg alloys. This work proposed that a synergistic enhancement of strength and ductility could be achieved through tuning interlayer dwell time(IDT) in the wire and arc additive manufacturing(WAAM) process of Mg alloy.The thermal couples were used to monitor the thermal history during the WAAM process. Additionally, the effect of different IDTs on the microstructure characteristics and resultant mechanical properties of WAAM-processed Mg alloy thin-wall were investigated. The results showed that the stable temperature of the thin-wall component could reach 290 ℃ at IDT=0s, indicating that the thermal accumulation effect was remarkable. Consequently, unimodal coarse grains with an average size of 39.6 μm were generated, and the resultant room-temperature tensile property was poor. With the IDT extended to 60s, the thermal input and thermal dissipation reached a balance, and the stable temperature was only 170 ℃, closing to the initial temperature of the substrate. A refined grain structure with bimodal size distribution was obtained. The remelting zone had fine grains with the size of 15.2 μm, while the arc zone owned coarse grains with the size of 24.5 μm.The alternatively distributed coarse and fine grains lead to the elimination of strength-ductility trade-off. The ultimate tensile strength and elongation of the samples at IDT=60s are increased by 20.6 and 75.0% of those samples at IDT=0s, respectively. The findings will facilitate the development of additive manufacturing processes for advanced Mg alloys. 展开更多
关键词 Wire arc additive manufacturing Interlayer dwell time Strength-ductility Magnesium alloys
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Study on anisotropy of microstructure and mechanical properties of AZ31 magnesium alloy fabricated by wire arc additive manufacturing
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作者 Dong Ma Chun-jie Xu +4 位作者 jun tian Shang Sui Can Guo Xiang-quan Wu Zhong-ming Zhang 《China Foundry》 SCIE CAS CSCD 2023年第4期280-288,共9页
Based on wire arc additive manufacturing(WAAM)technology,AZ31 magnesium alloy in bulk was successfully fabricated,and its microstructure as well as mechanical properties in different planes were observed and analyzed.... Based on wire arc additive manufacturing(WAAM)technology,AZ31 magnesium alloy in bulk was successfully fabricated,and its microstructure as well as mechanical properties in different planes were observed and analyzed.The AZ31 magnesium alloy has a similar microstructure in the building direction(Z)and travel direction(X),both of which are equiaxed grains.There are heat-affected zones(HAZs)with coarse grains below the fusion line.The second phase is primarily composed of the Mg17Al12 phase,which is evenly distributed in different directions.In addition,the residual stress varies in different directions.There is no significant difference in the hardness of the AZ31 alloy along the Z and X directions,with the average hardness being 68.4 HV and 67.9 HV,respectively.Even though the specimens’ultimate tensile strength along the travel direction is higher in comparison to that along the building direction,their differences in elongation and yield strength are smaller,indicating that the anisotropy of the mechanical properties of the material is small. 展开更多
关键词 magnesium alloy wire arc additive manufacturing ANISOTROPY MICROSTRUCTURE mechanical properties
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应用型本科高校物理化学课程思政教学的探索与实践 被引量:5
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作者 赵洪波 乔秀丽 +3 位作者 田军 白晓波 王斌 迟彩霞 《大学化学》 CAS 2022年第10期125-130,共6页
当前专业课程与思政教育深度融合的教学模式是高等教育的改革重点。以地方应用型本科高校为载体,立足大学理工专业课程自身的特点,从教与学两方面入手,将学生做为主体,深刻挖掘课程中蕴含的思政元素,针对教学目标、内容、方法、考核等... 当前专业课程与思政教育深度融合的教学模式是高等教育的改革重点。以地方应用型本科高校为载体,立足大学理工专业课程自身的特点,从教与学两方面入手,将学生做为主体,深刻挖掘课程中蕴含的思政元素,针对教学目标、内容、方法、考核等方面对物理化学课程思政教学模式进行了初步探索和实践。与传统教学相比,提高了课堂教学质量和效果,进一步激发了学生学习的积极性和主动性,对德智体全面发展的应用型人才培养具有重要意义。 展开更多
关键词 应用型本科高校 课程思政 物理化学
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风化壳淋积型稀土矿一维柱浸过程的模拟(英文) 被引量:12
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作者 龙平 王观石 +2 位作者 田君 胡世丽 罗嗣海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第3期625-633,共9页
通过杯浸试验确定浸矿的离子交换模型为Kerr模型,得到Kerr模型的选择系数为12.59×10^(-10)L^2/g^2;采用对流-弥散方程描述柱浸过程铵根离子和稀土离子的运移规律,通过Kerr模型确定对流-弥散方程中的源汇项,运用顺序非迭代法解具有... 通过杯浸试验确定浸矿的离子交换模型为Kerr模型,得到Kerr模型的选择系数为12.59×10^(-10)L^2/g^2;采用对流-弥散方程描述柱浸过程铵根离子和稀土离子的运移规律,通过Kerr模型确定对流-弥散方程中的源汇项,运用顺序非迭代法解具有强非线性的对流-弥散方程,模拟稀土离子在土柱中的运移过程。与室内一维柱浸试验稀土离子的穿透曲线进行比较,两者的相关系数达到0.8724,说明本方法可以较为准确地模拟风化壳淋积型稀土矿一维柱浸过程。分析硫酸铵溶液浓度对稀土浸取率的影响,结果发现,最优硫酸铵溶液浓度(C_(op)^(NS))与稀土品位(η)满足线性关系。 展开更多
关键词 风化壳淋积型稀土矿 柱浸 离子交换 溶质运移
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Two New Pentacyclic Triterpenes from Sabia parviflora 被引量:15
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作者 Jin CHEN Bin CHEN +1 位作者 jun tian Feng E WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期345-348,共4页
Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.
关键词 Sabia parviflora pentacyclic triterpene acid 3b-dihydroxyl-olean-12-en-28-oic acid 1a 2a 3b-trihydroxyl-olean-12-en-28-oic acid.
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Paired associative stimulation improves synaptic plasticity and functional outcomes after cerebral ischemia 被引量:5
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作者 Yan Hu Tie-Cheng Guo +2 位作者 Xiang-Yu Zhang jun tian Yin-Shan Lu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第11期1968-1976,共9页
Paired associative stimulation is a relatively new non-invasive brain stimulation technique that combines transcranial magnetic stimulation and peripheral nerve stimulation. The effects of paired associative stimulati... Paired associative stimulation is a relatively new non-invasive brain stimulation technique that combines transcranial magnetic stimulation and peripheral nerve stimulation. The effects of paired associative stimulation on the excitability of the cerebral cortex can vary according to the time interval between the transcranial magnetic stimulation and peripheral nerve stimulation. We established a model of cerebral ischemia in rats via transient middle cerebral artery occlusion. We administered paired associative stimulation with a frequency of 0.05 Hz 90 times over 4 weeks. We then evaluated spatial learning and memory using the Morris water maze. Changes in the cerebral ultra-structure and synaptic plasticity were assessed via transmission electron microscopy and a 64-channel multi-electrode array. We measured mRNA and protein expression levels of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1 in the hippocampus using a real-time polymerase chain reaction and western blot assay. Paired associative stimulation treatment significantly improved learning and memory in rats subjected to cerebral ischemia. The ultra-structures of synapses in the CA1 area of the hippocampus in rats subjected to cerebral ischemia were restored by paired associative stimulation. Long-term potentiation at synapses in the CA3 and CA1 regions of the hippocampus was enhanced as well. The protein and mRNA expression of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1 increased after paired associative stimulation treatment. These data indicate that paired associative stimulation can protect cog-nition after cerebral ischemia. The observed effect may be mediated by increases in the mRNA and protein expression of brain-derived neurotrophic factor and N-methyl-D-aspartate receptor 1, and by enhanced synaptic plasticity in the CA1 area of the hippocampus. The animal experiments were approved by the Animal Ethics Committee of Tongji Medical College, Huazhong University of Science & Technology, China(approval No. TJ-A20151102) on July 11, 2015. 展开更多
关键词 cerebral ischemia paired associative stimulation cognitive function long-term POTENTIATION SYNAPTIC plasticity MORRIS water maze SYNAPTIC structure N-methyl-D-aspartic acid receptor BRAIN-DERIVED NEUROTROPHIC factor MULTI-ELECTRODE array neural regeneration
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Effects of nutritional and psychological status in gastrointestinal cancer patients on tolerance of treatment 被引量:7
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作者 jun tian Zhen-Chun Chen Li-Fang Hang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第30期4136-4140,共5页
AIM: To assess the effects of poor nutritional and psychological status on tolerance of cancer treatment and the recovery of physical performance status in patients with gastrointestinal cancer. METHODS: An epidemiolo... AIM: To assess the effects of poor nutritional and psychological status on tolerance of cancer treatment and the recovery of physical performance status in patients with gastrointestinal cancer. METHODS: An epidemiological survey with respect to nutritional and psychological status in patients with gastrointestinal cancer was conducted among 182 operated patients in four provincial-level hospitals from December 2005 to June 2006. The food frequency survey method, state-trait anxiety inventory (STAI) and depression status inventory (DSI) were used to obtain information about the diet and psychological status in the patients. Nutritional status in the participants was reflected by serum albumin (Alb), hemoglobin (HB) and body mass index (BMI). RESULTS: Alb, protein intake and anxiety were associated with the severity of side effects of treatment. The adjusted relative risk (RR) for Alb, protein intake and anxiety was 3.30 (95% CI: 1.08, 10.10, P = 0.03), 3.25 (95% CI: 1.06, 9.90, P = 0.04) and 1.48 (95% CI: 1.29, 1.70, P < 0.0001), respectively. Moreover, calorie intake, HB and depression were associated with the recovery of physical performance status in the patients. Adjusted relative risk was 2.12 (95% CI: 1.09, 4.03, P = 0.028), 2.05 (95% CI: 1.08, 3.88, P =0.026) and 1.07 (95% CI: 1.02, 1.12, P = 0.007), respectively. CONCLUSION: Both poor nutrition status and psychological status are independent risk factors for severe side effects of cancer treatment, and have impact on the recovery of physical performance status in patients after treatment. 展开更多
关键词 胃肠癌 化学治疗 心理状态 营养状态
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Dasycarine, a New Quinoline Alkaloid from Dictamnus dasycarpus 被引量:7
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作者 Jin CHEN Jing Sheng TANG +2 位作者 jun tian You Ping WANG Feng E WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第8期707-708,共2页
Dasycarine, a new quinoline alkaloid along with five known compounds, dictamine, dihydroobacunone, obacunone, fraxinellone and beta-sitosterol, were isolated from Dictamnus dasycarpus. The structure of dasycarine was ... Dasycarine, a new quinoline alkaloid along with five known compounds, dictamine, dihydroobacunone, obacunone, fraxinellone and beta-sitosterol, were isolated from Dictamnus dasycarpus. The structure of dasycarine was identified as 4, 5, 8- trimethoxyl -3- (3- methyl -2-butenyl)- 2- quinone by 1D and 2D NMR techniques. 展开更多
关键词 Dictamnus dasycarpus RUTACEAE ALKALOIDS dasycarine
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A novel true triaxial test system for microwave-induced fracturing of hard rocks 被引量:5
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作者 Xia-Ting Feng Jiuyu Zhang +4 位作者 Chengxiang Yang jun tian Feng Lin Shiping Li Xiangxin Su 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第5期961-971,共11页
This study introduces a test system for microwave-induced fracturing of hard rocks under true triaxial stress.The test system comprises a true triaxial stress loading system,an open-ended microwaveinduced fracturing s... This study introduces a test system for microwave-induced fracturing of hard rocks under true triaxial stress.The test system comprises a true triaxial stress loading system,an open-ended microwaveinduced fracturing system,a data acquisition system,an acoustic emission(AE)monitoring system,and an auxiliary specimen loading system.Microwave-induced surface and borehole fracturing tests under true triaxial stress were fulfilled for the first time,which overcomes the problem of microwave leakage in the coupling loading of true triaxial stress and microwave.By developing the dynamic monitoring system,the thermal response and fracture evolution were obtained during microwave irradiation.The monitoring system includes the infrared thermometry technique for monitoring rock surface temperature,the distributed optic fiber sensing technique for monitoring temperature in borehole in rock,the AE technique and two-dimensional digital speckle correlation technique for monitoring the evolution of thermal damage and the rock fracturing process.To validate the advantages of the test system and investigate the characteristics of microwave-induced fracturing of hard rocks,the study demonstrates the experimental methods and results for microwave-induced surface and borehole fracturing under true triaxial stress.The results show that thermal cracking presented intermittent characteristics(calm eactiveecalm)during microwave-induced surface and borehole fracturing of basalt.In addition,true triaxial stress can inhibit the development and distribution of thermal cracks during microwave-induced surface fracturing.When microwave-induced borehole fracturing occurs,it promotes the distribution of thermal cracks in rock,but inhibits the width of cracks.The results also prove the reliability of the test system. 展开更多
关键词 Deep hard rock engineering True triaxial apparatus Microwave-induced fracturing of hard rocks Electromagnetic compatibility Dynamic monitoring Evolution of rock fracturing
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Assessment of the relationship between resilience and quality of life in patients with digestive cancer 被引量:5
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作者 jun tian Jin-Sheng Hong 《World Journal of Gastroenterology》 SCIE CAS 2014年第48期18439-18444,共6页
AIM:To study the relationship between resilience and quality of life(QOL)in patients with digestive cancer.METHODS:The resilience of patients was measured prior to treatment,and their psychological distress,fatigue st... AIM:To study the relationship between resilience and quality of life(QOL)in patients with digestive cancer.METHODS:The resilience of patients was measured prior to treatment,and their psychological distress,fatigue status,and treatment side effects were assessed 3 wk after.Their QOL was measured after their treatment ended.A relationship model of these variables was constructed using path analysis.RESULTS:Resilience explained 33.2%of the variance in psychological distress,16.1%of the variance in fatigue,and 1.23%of the variance in side effects.The relationship between resilience and QOL was statistically significant(β=0.119,t=4.499,P<0.001)when psychological distress,fatigue,and side effects were absent from the regression model,whereas the adjusted regression coefficient of resilience was not statistically significant(t=1.562,P>0.05)when thesevariables were added.Psychological distress,together with fatigue and side effects,could explain 52.40%of the variance in QOL(P<0.05).Physiological distress accounted for 28.94%of the total effect on QOL,fatigue accounted for 33.72%,side effects accounted for 22.53%,and resilience accounted for 14.80%.CONCLUSION:Resilience is not an independent predictor of QOL in patients with digestive cancer,but it is a main factor influencing psychological distress and side effects. 展开更多
关键词 RESILIENCE PSYCHOLOGICAL DISTRESS FATIGUE Quality
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Time trends of incidence of digestive system cancers in changle of China during 1988-2002 被引量:5
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作者 jun tian Jian-Shun Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4569-4571,共3页
瞄准:在一个 15 年的时期上在中国的 Changle 分析消化系统癌症的发生。方法:数据集在 1988-2002 期间表现为标准化中国的年度发生的时间系列。线性回归模型被用来分析胃,肝,食管和肤色的发生表面的癌症。结果:为为男人和女人的胃... 瞄准:在一个 15 年的时期上在中国的 Changle 分析消化系统癌症的发生。方法:数据集在 1988-2002 期间表现为标准化中国的年度发生的时间系列。线性回归模型被用来分析胃,肝,食管和肤色的发生表面的癌症。结果:为为男人和女人的胃和食管癌症发生的时间系列的线性回归模型是统计上重要的(P 【 0.05 ) ;为肝癌症并且为肤色的回归模型表面的癌症为男人是统计上重要的(P 【 0.05 ) 。结论:为在趋势下面有的男人和女人的胃和食管癌症的发生率。为男人,肝癌症有一下面表面的癌症有的发生和肤色的趋势发生率的一个向上的趋势。 展开更多
关键词 消化道肿瘤 中国 肝疾病 食道
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Unrevealing the effects of low temperature on cycling life of 21700-type cylindrical Li-ion batteries 被引量:4
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作者 Daozhong Hu Gang Chen +8 位作者 jun tian Ning Li Lai Chen Yuefeng Su Tinglu Song Yun Lu Duanyun Cao Shi Chen Feng Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期104-110,共7页
The low-temperature performance of Li-ion batteries(LIBs) has important impacts on their commercial applications. Besides the metallic lithium deposition, which is regarded as one of the main failure mechanisms of the... The low-temperature performance of Li-ion batteries(LIBs) has important impacts on their commercial applications. Besides the metallic lithium deposition, which is regarded as one of the main failure mechanisms of the LIBs at low temperatures, the synergistic effects originating from the cathode, anode, electrolyte, and separators to the batteries are still not clear. Here, the 21700-type cylindrical batteries were evaluated at a wide range of temperatures to investigate the failure mechanism of batteries. Voltage relaxation, and the post-mortem analysis combined with the electrochemical tests, unravel that the capacity degradation of batteries at low temperature is related to the lithium plating at graphite anodes,the formation of unsatisfied solid deposited/decomposed electrolyte mixture phase on the anode, the precipitation of solvent in the electrolytes and the block of separator pores, and the uneven dissolved transition metal-ions from the cathode. We hope this finding may open up a new avenue to alleviate the capacity degradation of advanced LIBs at low temperatures and shed light on the development of outstanding low-temperature LIBs via simultaneous optimization of all the components including electrodes, electrolytes and separators. 展开更多
关键词 Low temperature Cycling life Lithium plating Solid deposited/decomposed electrolyte mixture phase Voltage relaxation
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A New Benzylisoquinoline Alkaloid from Sabia parviflora 被引量:6
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作者 Jin CHEN Bin CHEN +1 位作者 jun tian Feng E WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第5期426-427,共2页
A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the... A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis. 展开更多
关键词 Sabia parviflora benzylisoquinoline alkaloid 1 2 3 4-tetrahydro-5-hydroxyl-8- methoxyl-2-methyl-4'-methoxyl-benzylisoquinoline.
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Preparation of crystalline rare earth carbonates with large particle size from the lixivium of weathered crust elution-deposited rare earth ores 被引量:4
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作者 Jing-qun Yin Zhi-qiang Zou jun tian 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第11期1482-1488,共7页
Crystalline rare-earth(RE)carbonates having large particle size were prepared from the lixivium of weathered crust elution-deposited rare-earth ores using the precipitation method with ammonium bicarbonate as the prec... Crystalline rare-earth(RE)carbonates having large particle size were prepared from the lixivium of weathered crust elution-deposited rare-earth ores using the precipitation method with ammonium bicarbonate as the precipitant.Their chemical composition was studied using elemental and thermogravimetric analyses(TGA),and their structure and morphology were characterized using Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),and scanning electron microscopy(SEM).The results demonstrate that the crystalline rareearth carbonate is a hydrated basic carbonate or oxycarbonate and not astable intermediate carbonate in the process of thermal decomposition.The particle size of crystalline rare-earth carbonates with large particle size is in the range of 50–200μm.With an RE2O3 content of up to 95wt%,the quality of crystalline rare-earth carbonates is higher compared to the Chinese National Standard(GB/T 28882–2012).The quality of the product is superior to the Chinese National Standard. 展开更多
关键词 rare-earth ores precipitation crystalline rare-earth carbonate large particle size
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Pseudohyperkalemia with Myelofibrosis after Splenectomy 被引量:2
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作者 Sheng-li Liu Lu-wei Zhang jun tian 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第4期258-260,共3页
SEUDOHYPERKALEMIA refers the serum potassiumlevel is higher than plasma potassium due tovarious reasons in vitro monitoring, but actualpotassium level in vivo is at the normal range. Aseries of inappropriate clinical ... SEUDOHYPERKALEMIA refers the serum potassiumlevel is higher than plasma potassium due tovarious reasons in vitro monitoring, but actualpotassium level in vivo is at the normal range. Aseries of inappropriate clinical interventions due to initialfailure to recognize it may actually decrease potassiumlevel,which could cause life-threatening condition. Here wereport a patient with myelofibrosis who occurred spurioushyperkalemia after splenectomy, aiming at emphasizingthe importance of recognizing pseudodyperkalemia. 展开更多
关键词 pseudohyperkalemia SERUM POTASSIUM PLASMA POTASSIUM MYELOFIBROSIS SPLENECTOMY
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Emergency Tasks Planning Based on Formal Modeling of Emergency Plan and HTN Planning System SHOP2 被引量:3
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作者 jun tian Zhi Li 《Intelligent Information Management》 2012年第6期357-363,共7页
A theoretical approach of ordered emergency tasks generation is proposed for dealing with a specific emergency event rapidly, exactly and effectively. According to the general principles of an emergency plan developed... A theoretical approach of ordered emergency tasks generation is proposed for dealing with a specific emergency event rapidly, exactly and effectively. According to the general principles of an emergency plan developed to response to an emergency management, a workflow model is employed to complete the formal modeling of concrete emergency plan firstly. Then the HTN planning system SHOP2 is introduced, the transformation method of domain knowledge from emergency domain to SHOP2 domain is studied. At last, the general procedure to solve the emergency decision prob-lems and to generate executive emergency tasks is set up drawing support from SHOP2 planning system, which will combine the principles (or knowledge) of emergency plan and the real emergency situations. 展开更多
关键词 EMERGENCY Plan WORKFLOW Model HTN PLANNING SYSTEM SHOP2 EMERGENCY Task
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