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Stochastic ordering of medians in exchangeable trivariate normal vectors
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作者 Ahad Jamalizadeh Mohsen Madadi +1 位作者 Mehdi Amiri N.Balakrishnan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第2期148-156,共9页
In this paper, we establish the stochastic ordering of median from an exchangeable trivaxiate normal vector based on the strength of the correlation coefficient. Specifically, by considering two exchangeable trivariat... In this paper, we establish the stochastic ordering of median from an exchangeable trivaxiate normal vector based on the strength of the correlation coefficient. Specifically, by considering two exchangeable trivariate normal vectors with different correlation coefficients, we show that the absolute value of the median in the vector with smaller correlation coefficient is stochastically smaller than the absolute value of the median in the vector with larger correlation coefficient. We prove this result by utilizing skew-normal distributions. 展开更多
关键词 Stochastic ordering Exchangeable trivariate normal distribution Order statistics MEDIAN Skew-normal distribution 2nd skew-normal distribution.
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基于NDVI数据的陇南市植被覆盖度时空演变
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作者 金雅铖 卫亚星 《绿色科技》 2024年第9期206-211,227,共7页
为研究陇南市的植被覆盖变化,基于2001—2020年归一化差异植被指数数据,采用像元二分模型最大值合成植被覆盖度,通过趋势分析、显著性检验,Hurst指数等方法,系统地分析甘肃省陇南市近20年来植被覆盖度的时空演化特征,并对其发展趋势进... 为研究陇南市的植被覆盖变化,基于2001—2020年归一化差异植被指数数据,采用像元二分模型最大值合成植被覆盖度,通过趋势分析、显著性检验,Hurst指数等方法,系统地分析甘肃省陇南市近20年来植被覆盖度的时空演化特征,并对其发展趋势进行预测。结果表明:①陇南市植被覆盖度整体呈现出一个波动性的上升趋势,变化速率在(-0.0417208~0.0479985)/a;②不同地区的植被覆盖度稳定性存在明显的差异,其中植被覆盖稳定不变区域占比7.26%,明显改善区域占比31.12%,严重退化区域占比9.39%;③在植被覆盖演变过程中,持续性和反持续性呈现出交错的分布模式,总体上主要呈现为弱持续性的序列。研究结果可为陇南市生态环境的修复和保护工作提供参考依据。 展开更多
关键词 植被覆盖度 时空演变 Theil-Sen Median趋势分析 陇南市
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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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作者 SHAN Xiao Yun ZOU Yan +10 位作者 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 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第3期254-265,共12页
Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible rel... Objective Studies on the relationship between iodine,vitamin A(VA),and vitamin D(VD)and thyroid function are limited.This study aimed to analyze iodine and thyroid-stimulating hormone(TSH)status and their possible relationships with VA,VD,and other factors in postpartum women.Methods A total of 1,311 mothers(896 lactating and 415 non-lactating)from Hebei,Zhejiang,and Guangxi provinces were included in this study.The urinary iodine concentration(UIC),TSH,VA,and VD were measured.Results The median UIC of total and lactating participants were 142.00µg/L and 139.95µg/L,respectively.The median TSH,VA,and VD levels in all the participants were 1.89 mIU/L,0.44μg/mL,and 24.04 ng/mL,respectively.No differences in the UIC were found between lactating and non-lactating mothers.UIC and TSH levels were significantly different among the three provinces.The rural UIC was higher than the urban UIC.Obese mothers had a higher UIC and a higher prevalence of excessive TSH.Higher UICs and TSHs levels were observed in both the VD deficiency and insufficiency groups than in the VD-sufficient group.After adjustment,no linear correlation was observed between UIC and VA/VD.No interaction was found between vitamins A/D and UIC on TSH levels.Conclusion The mothers in the present study had no iodine deficiency.Region,area type,BMI,and VD may be related to the iodine status or TSH levels. 展开更多
关键词 Median urinary iodine concentration Thyroid-stimulating hormone Vitamin A Vitamin D Postpartum women
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2000—2020年莆田木兰溪流域植被覆盖时空变化
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作者 徐延芳 《江苏林业科技》 2024年第5期29-34,共6页
木兰溪流域作为福建省重要的水源涵养地,也是生态环境敏感脆弱的区域,对该流域的植被覆盖进行检测和分析具有重要意义。基于空间分辨率为1 km的2000—2020年NDVI年时序数据,采用Theil-Sen Median趋势分析法和Mann-Kendall检验,并叠加土... 木兰溪流域作为福建省重要的水源涵养地,也是生态环境敏感脆弱的区域,对该流域的植被覆盖进行检测和分析具有重要意义。基于空间分辨率为1 km的2000—2020年NDVI年时序数据,采用Theil-Sen Median趋势分析法和Mann-Kendall检验,并叠加土地利用数据和海拔高度数据,分析了木兰溪流域不同土地利用类型和不同高程的植被覆盖变化趋势。结果表明:(1)从时间变化上看,2000—2020年植被覆盖区域NDVI年均值波动不大,整个研究时段内的平均值为0.69;(2)从空间分布上看,研究区NDVI呈现“西高东低”的特征;(3)从变化趋势上看,研究区2000—2020年地表植被覆盖改善面积大于退化面积,明显改善区域主要分布在仙游县和城厢区,其中仙游县植被覆盖明显改善所占比例最高,为52%。明显退化区域主要分布在涵江区和荔城区,其中涵江区植被覆盖明显退化,所占比例最高,为93%;(4)在不同土地利用类型中,林地、草地和未利用土地的植被覆盖明显改善所占比例最高,耕地、建设用地和水域的植被覆盖明显退化所占比例最高;(5)在不同高程带下,随着高程的增加,植被覆盖明显改善逐渐增加,植被覆盖明显退化、轻微退化逐渐减少;在特高高程带上,植被覆盖甚至未发生退化。 展开更多
关键词 木兰溪流域 时空变化 植被覆盖 NDVI Theil-Sen Median
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Comparing Short-Term Outcomes of Right Mini-Thoracotomy and Median Sternotomy for Isolated Left Atrial Myxoma Excision
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作者 Munjerin Refat Synthee Satyajit Sharma +8 位作者 Md. Abir Tazim Chowdhury Munama Magdum Muhit Abdullah Md. Zafar-Al-Nimari Md. Ahaduzzaman Dewan Iftakher Reza Chowdhury Saikat Dasgupta Prasanta Kumar Chandra Farooque Ahmed 《World Journal of Cardiovascular Surgery》 2024年第10期157-165,共9页
Background: Left atrial myxoma (LAM) is the most common heart tumor in adults, requiring prompt surgical removal to prevent complications like valvular obstruction or embolization. Objectives: This study aimed to comp... Background: Left atrial myxoma (LAM) is the most common heart tumor in adults, requiring prompt surgical removal to prevent complications like valvular obstruction or embolization. Objectives: This study aimed to compare early postoperative outcomes between two surgical approaches—right mini-thoracotomy and median sternotomy—for the removal of isolated left atrial myxoma. Methods: We conducted a prospective observational study at the Department of Cardiac Surgery, National Heart Foundation Hospital & Research Institute (NHFH&RI), Mirpur, Dhaka, from March 2017 to August 2019. Twenty-eight patients undergoing surgery for isolated left atrial myxoma were included. The surgical approach was determined by the operating surgeon. We analyzed outcomes like intubation time, Intensive Care Unit (ICU) stay, pain levels (Visual Analogue Scale score), and overall hospital stay using SPSS. Statistical significance was set at p Results: Patients in the right mini-thoracotomy group had longer mean intubation times (11.43 vs. 5.93 hours, p Conclusion: Despite longer intubation and ICU times, the right mini-thoracotomy approach offers a minimally invasive alternative for isolated left atrial myxoma excision, with favorable outcomes overall. 展开更多
关键词 Left Atrial Myxoma Mini-Thoracotomy Median Sternotomy Cardiac Surgery
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The Goldbach Conjecture Is True
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作者 Jie Hou 《Open Journal of Discrete Mathematics》 2024年第3期29-41,共13页
Let 2m>2, m∈ℤ, be the given even number of the Strong Goldbach Conjecture Problem. Then, m can be called the median of the problem. So, all Goldbach partitions (p,q)exist a relationship, p=m−dand q=m+d, where p≤q... Let 2m>2, m∈ℤ, be the given even number of the Strong Goldbach Conjecture Problem. Then, m can be called the median of the problem. So, all Goldbach partitions (p,q)exist a relationship, p=m−dand q=m+d, where p≤qand d is the distance from m to either p or q. Now we denote the finite feasible solutions of the problem as S(2m)={ (2,2m−2),(3,2m−3),⋅⋅⋅,(m,m) }. If we utilize the Eratosthenes sieve principle to efface those false objects from set S(2m)in pistages, where pi∈P, pi≤2m, then all optimal solutions should be found. The Strong Goldbach Conjecture is true since we proved that at least one optimal solution must exist to the problem. The Weak Goldbach Conjecture is true since it is a special case of the Strong Goldbach Conjecture. Therefore, the Goldbach Conjecture is true. 展开更多
关键词 MEDIAN The Feasible Goldbach Partitions The Optimal Goldbach Partitions CONGRUENCES Effacement
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近30年广东省降雨集中度时空分布特征及其影响因素分析
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作者 罗柱 牛亚朝 付志君 《广东水利水电》 2024年第11期38-42,60,共6页
研究降雨集中度的时空分布特征可为水资源管理、预防洪涝灾害提供重要的理论依据。该文以广东省为研究区域,分析月降雨集中度的时空分布特征,采用Theil-Sen Median分析和Mann-Kendall检验探究降雨集中度的变化趋势特征,使用M-K突变点检... 研究降雨集中度的时空分布特征可为水资源管理、预防洪涝灾害提供重要的理论依据。该文以广东省为研究区域,分析月降雨集中度的时空分布特征,采用Theil-Sen Median分析和Mann-Kendall检验探究降雨集中度的变化趋势特征,使用M-K突变点检验识别出降雨集中度的突变点,基于交叉小波分析,揭示影响显著性变化区域降雨集中度时空分布特征的驱动力因素,结果表明:1991—2022年间降雨量空间分布呈现出中西部降雨较多,东北部降雨较少的特点,整体呈现出“V”型波动;广东省降雨在年内分布具有明显的季节性,研究区的降雨集中度呈现出不显著增加的趋势,在粤西地区呈现出减少趋势;粤西地区的降雨集中度受到大气环流异常因子的显著影响,其中以北极涛动(AO)的影响最为明显。 展开更多
关键词 降雨集中度 交叉小波 Theil-Sen Median分析 M-K检验
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Simultaneous Compression of the Celiac Trunk, Superior Mesenteric Artery, and Renal Arteries by the Median Arcuate Ligament: About One Case
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作者 Siddick Oumar Kenza Fathallah +5 位作者 Hassan Ahmed Aicha Merzem Hasnaa Belgadir Omar Amriss Nadia Moussali Naima El Benna 《Open Journal of Medical Imaging》 2024年第3期106-113,共8页
Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insert... Median arcuate ligament syndrome (MALS), is a rare abdominal vascular compression syndrome caused by the compression of the proximal celiac trunk by the median arcuate ligament. According to many authors, a low insertion of the diaphragmatic crura or an abnormally high origin of the celiac trunk from the aorta can cause compression of the celiac artery. Usually, patients with MALS are asymptomatic. Computed tomography (CT) angiography of the abdomen is the main imaging modality to confirm the diagnosis. The coexistence of celiac trunk and superior mesenteric artery compression by the median arcuate ligament is rarely described in the literature. To our knowledge, until now, a simultaneous combination of three abdominal vascular compressions by the median arcuate ligament has never been described. From this case, we report a simultaneous compression of the celiac trunk, superior mesenteric artery, and renal arteries by the median arcuate ligament. 展开更多
关键词 Median Arcuate Ligament Syndrome (MALS) Celiac Trunk Compression Superior Mesenteric Artery and Renal Arteries Compression Computed Tomography Angiography
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广东省植被叶面积指数时空变化特征及其影响因素 被引量:6
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作者 毛智慧 黎丽莉 +1 位作者 程露 杜建军 《地球科学与环境学报》 CAS 北大核心 2023年第4期907-919,共13页
植被变化是评价生态环境和衡量地表植被状况的重要指标之一,探讨植被的时空动态变化特征及其影响因素对生态环境的保护及植被的恢复建设具有重要意义。基于MODIS叶面积指数(LAI)卫星遥感产品、气象数据和社会经济数据,运用Theil-Sen Med... 植被变化是评价生态环境和衡量地表植被状况的重要指标之一,探讨植被的时空动态变化特征及其影响因素对生态环境的保护及植被的恢复建设具有重要意义。基于MODIS叶面积指数(LAI)卫星遥感产品、气象数据和社会经济数据,运用Theil-Sen Median趋势分析、Mann-Kendall显著性检验、Hurst指数分析和地理探测器等方法,探究了广东省2003~2020年叶面积指数的时空变化特征及其影响因素。结果表明:2003~2020年,广东省叶面积指数年际变化呈现为波动上升趋势(增长率为0.219/10a),叶面积指数季节均值的增长率从大到小依次为冬季(0.405/10a)、春季(0.251/10a)、秋季(0.139/10a)和夏季(0.111/10a);在空间上,叶面积指数表现为西北高、东南低的特征,低值区主要集中在珠江三角洲地区和沿海经济区;叶面积指数未来变化趋势以弱反持续性和弱持续性为主,持续改善区域的面积远远大于持续退化区域的面积,说明广东省植被覆盖未来改善的可能性较大;叶面积指数主要影响因素为高程、人口密度和GDP,其中高程的影响最为显著,对叶面积指数空间分异的解释力为16.9%,且双因素的交互作用能增强对叶面积指数空间分异的解释力。 展开更多
关键词 叶面积指数 Theil-Sen Median趋势分析 Mann-Kendall显著性检验 HURST指数 地理探测器 交互作用 时空变化 广东
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An ultrasound-guided percutaneous electrical nerve stimulation regimen devised using finite element modeling promotes functional recovery after median nerve transection 被引量:3
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作者 Xiao-Lei Chu Xi-Zi Song +5 位作者 Yu-Ru Li Zi-Ren Wu Qi Li Qing-Wen Li Xiao-Song Gu Dong Ming 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期683-688,共6页
Percutaneous electrical nerve stimulation of an injured nerve can promote and accelerate peripheral nerve regeneration and improve function.When performing acupuncture and moxibustion,locating the injured nerve using ... Percutaneous electrical nerve stimulation of an injured nerve can promote and accelerate peripheral nerve regeneration and improve function.When performing acupuncture and moxibustion,locating the injured nerve using ultrasound before percutaneous nerve stimulation can help prevent further injury to an already injured nerve.However,stimulation parameters have not been standardized.In this study,we constructed a multi-layer human forearm model using finite element modeling.Taking current density and activated function as optimization indicators,the optimal percutaneous nerve stimulation parameters were established.The optimal parameters were parallel placement located 3 cm apart with the injury site at the midpoint between the needles.To validate the efficacy of this regimen,we performed a randomized controlled trial in 23 patients with median nerve transection who underwent neurorrhaphy.Patients who received conventional rehabilitation combined with percutaneous electrical nerve stimulation experienced greater improvement in sensory function,motor function,and grip strength than those who received conventional rehabilitation combined with transcutaneous electrical nerve stimulation.These findings suggest that the percutaneous electrical nerve stimulation regimen established in this study can improve global median nerve function in patients with median nerve transection. 展开更多
关键词 finite element modeling median nerve transection nerve regeneration NEUROREHABILITATION percutaneous electrical nerve stimulation peripheral nerve injury randomized controlled trial
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蒙古高原250 m分辨率植被生长季NDVI年际时空变化数据集(2001-2021年)
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作者 徐洋 杨雅萍 +1 位作者 陈晓娜 乐夏芳 《中国科学数据(中英文网络版)》 CSCD 2023年第1期46-57,共12页
蒙古高原对我国北方生态安全有着重要的影响,植被对气候变化和生态环境有着重要的指示作用,植被的时空变化格局与趋势是评估区域生态状况的重要指标。本研究基于MOD13Q1 NDVI数据,利用R语言调用Google Earth Engine服务进行月度最大值合... 蒙古高原对我国北方生态安全有着重要的影响,植被对气候变化和生态环境有着重要的指示作用,植被的时空变化格局与趋势是评估区域生态状况的重要指标。本研究基于MOD13Q1 NDVI数据,利用R语言调用Google Earth Engine服务进行月度最大值合成,之后使用R语言terra包完成生长季年度均值合成、变异系数计算、Theil-Sen median趋势分析和Mann-Kendall显著性检验以及Hurst指数计算,形成了2001-2021年蒙古高原250m分辨率植被生长季NDVI年际时空变化数据集,包含蒙古高原地区生长季NDVI时空变化格局和趋势特征信息。通过在国家地球系统科学数据中心共享数据,为科学认识蒙古高原区域植被覆盖时空变化规律提供数据支撑。 展开更多
关键词 蒙古高原 植被指数 Theil-Sen median趋势分析 MANN-KENDALL检验 变异系数 HURST指数 生长季 rgee
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蒙古高原500 m分辨率植被物候及变化趋势数据集(2001-2019年)
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作者 张寅飞 杨雅萍 +1 位作者 乐夏芳 徐洋 《中国科学数据(中英文网络版)》 CSCD 2023年第1期23-36,共14页
蒙古高原地处欧亚大陆中部,是典型的干旱半干旱地区,对气候变化高度敏感。植被物候是气候条件季节和年际变化最直观、最敏感的生物指示器,利用植被物候数据可以很好地对蒙古高原的生态情况、气候变化进行探究。本研究基于MODIS土地覆盖... 蒙古高原地处欧亚大陆中部,是典型的干旱半干旱地区,对气候变化高度敏感。植被物候是气候条件季节和年际变化最直观、最敏感的生物指示器,利用植被物候数据可以很好地对蒙古高原的生态情况、气候变化进行探究。本研究基于MODIS土地覆盖动态产品(MCD12Q2 C6),通过提取子数据集、镶嵌拼接、投影转换和裁剪等预处理操作,采用非参数Theil-Sen Median趋势分析与Mann-Kendall显著性检验方法,生成了2001-2019年蒙古高原500 m分辨率植被生长季开始时间、生长季结束时间、生长季节长度、生长峰值时间四个物候期以及变化趋势数据。本数据可反映蒙古高原19年植被物候期的时空变化情况,结合温度、降水等气候要素,可探究植被物候变化对环境要素的响应及其反馈机制,并可为植被变化分析、气候变化、碳循环等方面的研究提供数据支持。 展开更多
关键词 蒙古高原 植被物候 时空分布 Theil-Sen Median趋势分析 Mann-Kendall显著性检验 MCD12Q2 2001-2019
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Median arcuate ligament syndrome often poses a diagnostic challenge: A literature review with a scope of our own experience 被引量:1
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作者 Alexandros Giakoustidis Stavros Moschonas +6 位作者 Gregory Christodoulidis Danae Chourmouzi Anna Diamantidou Sophia Masoura Eleni Louri Vasileios N Papadopoulos Dimitrios Giakoustidis 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第6期1048-1055,共8页
The median arcuate ligament syndrome(MALS)is recognized as a rare clinical entity,characterized by chronic post-prandial abdominal pain,nausea,vomiting,and unintentional weight loss.Due to its vague symptomatology,it ... The median arcuate ligament syndrome(MALS)is recognized as a rare clinical entity,characterized by chronic post-prandial abdominal pain,nausea,vomiting,and unintentional weight loss.Due to its vague symptomatology,it is mainly regarded as a diagnosis of exclusion.Patients can often be misdiagnosed for several years before a correct diagnosis is established,also due to a medical team’s clinical suspicion.We present a case series of two patients who suffered from MALS and were treated successfully.The first patient is a 32-year-old woman,presenting with post-prandial abdominal pain and weight loss that have lasted for the past ten years.The second patient,a 50-year-old woman,presented with similar symptomatology,with the symptoms lasting for the last five years.Both cases were treated by laparoscopic division of the median arcuate ligament fibers,which alleviated extrinsic pressure from the celiac artery.Previous cases of MALS were retrieved from PubMed,to assemble a better diagnostic algorithm and propose a treatment method of choice.The literature review suggests an angiography with a respiratory variation protocol as the diagnostic modality of choice,along with the laparoscopic division of the median arcuate ligament fibers as the proposed treatment of choice. 展开更多
关键词 Median arcuate ligament syndrome Dunbar syndrome Celiac trunk compression syndrome Celiac artery compression syndrome Case series Review
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Classification of Multi-view Digital Mammogram Images Using SMO-WkNN
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作者 P.Malathi G.Charlyn Pushpa Latha 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1741-1758,共18页
Breast cancer(BCa)is a leading cause of death in the female population across the globe.Approximately 2.3 million new BCa cases are recorded globally in females,overtaking lung cancer as the most prevalent form of can... Breast cancer(BCa)is a leading cause of death in the female population across the globe.Approximately 2.3 million new BCa cases are recorded globally in females,overtaking lung cancer as the most prevalent form of cancer to be diagnosed.However,the mortality rates for cervical and BCa are significantly higher in developing nations than in developed countries.Early diagnosis is the only option to minimize the risks of BCa.Deep learning(DL)-based models have performed well in image processing in recent years,particularly convolutional neural network(CNN).Hence,this research proposes a DL-based CNN model to diagnose BCa from digitized mammogram images.The main objective of this research is to develop an accurate and efficient early diagnosis model for BCa detection.This proposed model is a multi-view-based computer-aided diagnosis(CAD)model,which performs the diagnosis of BCa on multi-views of mammogram images like medio-lateral-oblique(MLO)and cranio-caudal(CC).The digital mammogram images are collected from the digital database for screening mammography(DDSM)dataset.In preprocessing,median filter and contrast limited adaptive histogram equalization(CLAHE)techniques are utilized for image enhancement.After preprocessing,the segmentation is performed using the region growing(RG)algorithm.The feature extraction is carried out from the segmented images using a pyramidal histogram of oriented gradients(PHOG)and the AlextNet model.Finally,the classification is performed using the weighted k-nearest neighbor(WkNN)optimized with sequential minimal optimization(SMO).The classified images are evaluated based on accuracy,recall,precision,specificity,f1-score,and mathews correlation coefficient(MCC).Additionally,the false positive and error rates are evaluated.The proposed model obtained 98.57%accuracy,98.61%recall,99.25%specificity,98.63%precision,97.93%f1-score,96.26%MCC,0.0143 error rate,and 0.0075 false positive rate(FPR).Compared to the existing models,the research model has obtained better performances and outperformed the other models. 展开更多
关键词 Breast cancer DDSM CLAHE median filter region growing PHOG AlexNet SMO-WkNN
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2000-2021年青藏高原地区地表净辐射的时空变化
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作者 崔玉祥 胡斯勒图 +3 位作者 李同文 姬大彬 张颢 施建成 《空间科学学报》 CAS CSCD 北大核心 2023年第6期1150-1159,共10页
基于CERES卫星提供的2000年3月至2022年2月SYN1 deg–Level 3辐射数据,结合Theil-Sen Median趋势分析、Mann-Kendall检验以及EOF分析等方法,分析了22年间青藏高原地表净辐射的时空变化规律。研究发现,在空间分布特征上,青藏高原地表净... 基于CERES卫星提供的2000年3月至2022年2月SYN1 deg–Level 3辐射数据,结合Theil-Sen Median趋势分析、Mann-Kendall检验以及EOF分析等方法,分析了22年间青藏高原地表净辐射的时空变化规律。研究发现,在空间分布特征上,青藏高原地表净辐射总体呈现南高北低的分布特征,地表净辐射变化趋势具有高度一致性,但在青藏高原南部地表净辐射变化量级远高于青藏高原北部;在时间演化特征上,地表净辐射呈现准正弦振动,年周期变化明显,特别是2016-2017年出现突变,下降约5.52 W·m^(–2),同期云覆盖度年平均值提高约18.75%。 展开更多
关键词 青藏高原 地表净辐射 时空变化 EOF分析 Theil-Sen Median趋势 MANN-KENDALL检验
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Nerve function restoration following targeted muscle reinnervation after varying delayed periods
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作者 Yuanheng Li Jiangping Huang +4 位作者 Yuling Chen Shanshan Zhu Zhen Huang Lin Yang Guanglin Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第12期2762-2766,共5页
Targeted muscle reinnervation has been proposed for reconstruction of neuromuscular function in amputees.However,it is unknown whether performing delayed targeted muscle reinnervation after nerve injury will affect re... Targeted muscle reinnervation has been proposed for reconstruction of neuromuscular function in amputees.However,it is unknown whether performing delayed targeted muscle reinnervation after nerve injury will affect restoration of function.In this rat nerve injury study,the median and musculocutaneous nerves of the forelimb were transected.The proximal median nerve stump was sutured to the distal musculocutaneous nerve stump immediately and 2 and 4 weeks after surgery to reinnervate the biceps brachii.After targeted muscle reinnervation,intramuscular myoelectric signals from the biceps brachii were recorded.Signal amplitude gradually increased with time.Biceps brachii myoelectric signals and muscle fiber morphology and grooming behavior did not significantly differ among rats subjected to delayed target muscle innervation for different periods.Targeted muscle reinnervation delayed for 4 weeks can acquire the same nerve function restoration effect as that of immediate reinnervation. 展开更多
关键词 biceps brachii delayed nerve repair delayed targeted muscle reinnervation functional reconstruction grooming test implanted electrode intramuscular myoelectric signals median nerve motor function nerve transfer
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Automatic Detection and Classification of Insects Using Hybrid FF-GWO-CNN Algorithm
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作者 B.Divya M.Santhi 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1881-1898,共18页
Pest detection in agricultural cropfields is the most challenging task,so an effective pest detection technique is required to detect insects automatically.Image processing techniques are widely preferred in agricultur... Pest detection in agricultural cropfields is the most challenging task,so an effective pest detection technique is required to detect insects automatically.Image processing techniques are widely preferred in agricultural science because they offer multiple advantages like maximal crop protection,improved crop man-agement and productivity.On the other hand,developing the automatic pest mon-itoring system dramatically reduces the workforce and errors.Existing image processing approaches are limited due to the disadvantages like poor efficiency and less accuracy.Therefore,a successful image processing technique based on FF-GWO-CNN classification algorithm is introduced for effective pest monitor-ing and detection.The four-step image processing technique begins with image pre-processing,removing the insect image’s noise and sunlight illumination by utilizing an adaptive medianfilter.The insects’size and shape are identified using the Expectation Maximization Algorithm(EMA)based clustering technique,which involves not only clustering the data but also uncovering the correlations by visualizing the global shape of an image.Speeded up robust feature(SURF)method is employed to select the best possible image features.Eventually,the image with best features is classified by introducing a hybrid FF-GWO-CNN algorithm,which combines the benefits of Firefly(FF),Grey Wolf Optimization(GWO)and Convolutional Neural Network(CNN)classification algorithm for enhancing the classification accuracy.The entire work is executed in MATLAB simulation software.The test result reveals that the suggested technique has deliv-ered optimal performance with high accuracy of 97.5%,precision of 94%,recall of 92%and F-score value of 92%. 展开更多
关键词 Adaptive medianfilter EMA SURF FF algorithm GWO CNN
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Regulatory Genes Through Robust-SNR for Binary Classification Within Functional Genomics Experiments
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作者 Muhammad Hamraz Dost Muhammad Khan +6 位作者 Naz Gul Amjad Ali Zardad Khan Shafiq Ahmad Mejdal Alqahtani Akber Abid Gardezi Muhammad Shafiq 《Computers, Materials & Continua》 SCIE EI 2023年第2期3663-3677,共15页
The current study proposes a novel technique for feature selection by inculcating robustness in the conventional Signal to noise Ratio(SNR).The proposed method utilizes the robust measures of location i.e.,the“Median... The current study proposes a novel technique for feature selection by inculcating robustness in the conventional Signal to noise Ratio(SNR).The proposed method utilizes the robust measures of location i.e.,the“Median”as well as the measures of variation i.e.,“Median absolute deviation(MAD)and Interquartile range(IQR)”in the SNR.By this way,two independent robust signal-to-noise ratios have been proposed.The proposed method selects the most informative genes/features by combining the minimum subset of genes or features obtained via the greedy search approach with top-ranked genes selected through the robust signal-to-noise ratio(RSNR).The results obtained via the proposed method are compared with wellknown gene/feature selection methods on the basis of performance metric i.e.,classification error rate.A total of 5 gene expression datasets have been used in this study.Different subsets of informative genes are selected by the proposed and all the other methods included in the study,and their efficacy in terms of classification is investigated by using the classifier models such as support vector machine(SVM),Random forest(RF)and k-nearest neighbors(k-NN).The results of the analysis reveal that the proposed method(RSNR)produces minimum error rates than all the other competing feature selection methods in majority of the cases.For further assessment of the method,a detailed simulation study is also conducted. 展开更多
关键词 Median absolute deviation(MAD) classification feature selection high dimensional gene expression datasets signal to noise ratio
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De-Noising Brain MRI Images by Mixing Concatenation and Residual Learning(MCR)
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作者 Kazim Ali Adnan N.Qureshi +3 位作者 Muhammad Shahid Bhatti Abid Sohail Muhammad Hijji Atif Saeed 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1167-1186,共20页
Brain magnetic resonance images(MRI)are used to diagnose the different diseases of the brain,such as swelling and tumor detection.The quality of the brain MR images is degraded by different noises,usually salt&pep... Brain magnetic resonance images(MRI)are used to diagnose the different diseases of the brain,such as swelling and tumor detection.The quality of the brain MR images is degraded by different noises,usually salt&pepper and Gaussian noises,which are added to the MR images during the acquisition process.In the presence of these noises,medical experts are facing problems in diagnosing diseases from noisy brain MR images.Therefore,we have proposed a de-noising method by mixing concatenation,and residual deep learning techniques called the MCR de-noising method.Our proposed MCR method is to eliminate salt&pepper and gaussian noises as much as possible from the brain MRI images.The MCR method has been trained and tested on the noise quantity levels 2%to 20%for both salt&pepper and gaussian noise.The experiments have been done on publically available brain MRI image datasets,which can easily be accessible in the experiments and result section.The Structure Similarity Index Measure(SSIM)and Peak Signal-to-Noise Ratio(PSNR)calculate the similarity score between the denoised images by the proposed MCR method and the original clean images.Also,the Mean Squared Error(MSE)measures the error or difference between generated denoised and the original images.The proposed MCR denoising method has a 0.9763 SSIM score,84.3182 PSNR,and 0.0004 MSE for salt&pepper noise;similarly,0.7402 SSIM score,72.7601 PSNR,and 0.0041 MSE for Gaussian noise at the highest level of 20%noise.In the end,we have compared the MCR method with the state-of-the-art de-noising filters such as median and wiener de-noising filters. 展开更多
关键词 MR brain images median filter wiener filter concatenation learning residual learning MCR de-noising method
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Median neuropathy after multiple punctures of the forearm for catheterization:A case report
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作者 Tomoaki Suzuki Yuichiro Matsui +2 位作者 Daisuke Momma Takeshi Endo Norimasa Iwasaki 《World Journal of Clinical Cases》 SCIE 2023年第25期5941-5946,共6页
BACKGROUND Neuropathy may occur at some sites after catheterization for close examination of cardiac disease.Although the radial artery is considered a relatively uncomplicated site for catheterization,the radial arte... BACKGROUND Neuropathy may occur at some sites after catheterization for close examination of cardiac disease.Although the radial artery is considered a relatively uncomplicated site for catheterization,the radial artery and median nerve are in relatively close proximity,with the risk of median nerve injury depending on the angle of puncture.The purpose of this study was to report the outcomes of surgery performed for conservative therapy-resistant median neuropathy following forearm catheterization.CASE SUMMARY A 50-year-old woman experienced palsy from the right thumb to the radial side of the ring finger after catheterization from the radial artery of the right forearm.Paresthesia developed at the same site and a positive tinel-like sign was seen for the median nerve area at the high level of the puncture site.Nerve conduction study showed reduced compound muscle action potentials and loss of sensory nerve action potentials.Symptoms did not improve despite pharmacotherapy and the patient gradually developed flexion restrictions of the index and middle fingers.Median nerve injury and associated flexor tendon adhesion was diagnosed,and the patient was referred for surgery at 3 mo after injury.When the same area was opened,no injury to the median nerve epithelium was obvious,but the area of the positive tinel-like sign was highly adherent to surrounding tissue and to the flexor digitorum superficialis of the index and middle fingers.The surgery was terminated with adequate adhesion release.Rehabilitation was initiated postoperatively,improving neurological symptoms and range of motion of the fingers.Six months after surgery,the patient returned to daily activities without discomfort.CONCLUSION This case provides the appropriate diagnosis and treatment for a suspected peripheral nerve injury. 展开更多
关键词 CATHETERIZATION Median neuropathy Surgical treatment Case report
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