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Dynamic changes in physicochemical property,biogenic amines content and microbial diversity during the fermentation of Sanchuan ham 被引量:2
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作者 Zhongai Chen Hong Chen +4 位作者 Huan Du Cong Chen Kaixiang Lu Qiaoli Xue Yongjin Hu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期506-516,共11页
Sanchuan ham is appreciated in Yunnan Province,China,for its characteristic flavor and taste,while the microbial community structure and biogenic amines content remain unclear during fermentation processes.In this stu... Sanchuan ham is appreciated in Yunnan Province,China,for its characteristic flavor and taste,while the microbial community structure and biogenic amines content remain unclear during fermentation processes.In this study,we explored the physicochemical property,biogenic amines concentration and microbial diversity of external and internal Sanchuan ham by high-throughput sequencing during the processing of Sanchuan ham.Results showed that the nitrite remained at a stable level of 0.15 mg/kg which was significantly lower than the national health standard safety level of 20 mg/kg.In addition,compared with fresh hams,the content of total free amino acids in ripe Sanchuan ham has grown 14 folds;sour and bitter were the main tastes of Sanchuan ham.Notably,the concentration of cadaverine was the highest of all biogenic amines during the entire fermentation period.At the bacterial phyla level,Firmicutes and Actinobacteria were the two main phyla,while at the genus level,Staphylococcus was a significant strain throughout the whole fermentation.Moreover,the dry stage has a great impact on the succession change of microbial community structure.Simultaneously,the change trends and composition of bacteria in the interior have slight discrepancies with those of the exterior of Sanchuan ham. 展开更多
关键词 Sanchuan ham Nitrite cont ent Free amino acids CADAVERINE STAPHYLOCOCCUS
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ESTIM ATES OF ENERGIESAND MOMENTS FOR SOLUTIONS OF BOLTZM ANN-POISSON SYSTEM
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作者 CuiGuozhong Wang Yuanm ing Dept. ofAppl. Math., Southeast Univ., Nanjing 210096. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1999年第3期301-308,共8页
In this paper, the properties ofthe solutions ofBoltzm ann-Poisson system in three di- m ensions are considered. The estim ates ofthe energies (the kinetic and the potentialenergies) and the γ-th m om ents w ith γ... In this paper, the properties ofthe solutions ofBoltzm ann-Poisson system in three di- m ensions are considered. The estim ates ofthe energies (the kinetic and the potentialenergies) and the γ-th m om ents w ith γ∈[2,3) are obtained. The latter answ ers an open problem . 展开更多
关键词 Boltzm ann-Poisson system mom ents estim ates.
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Commentary on“Synchronized activity of sensory neurons initiates cortical synchrony in a model of neuropathic pain”
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作者 Lorenzo Di Cesare Mannelli Carla Ghelardini 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期728-728,共1页
In pat i e nt s,a s well as in animal mod e l s,hypersensitivity to external stimuli(hyperalgesia and allodynia)or spontaneous pain is often the first,and the most disabling,symptom of neuropathy(Davis et al.,2020).Th... In pat i e nt s,a s well as in animal mod e l s,hypersensitivity to external stimuli(hyperalgesia and allodynia)or spontaneous pain is often the first,and the most disabling,symptom of neuropathy(Davis et al.,2020).The increased activity of sensitive neurons drives pain development,making ion channel modulation a fundamental target for current pharmacotherapy as well as one of the most investigated by the R&D departments of pharmaceutical companies(Bennett et al.,2019). 展开更多
关键词 COMPANIES PAIN ent
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Overview of the Development of the Soybean Industry in the United States,Brazil and Argentina and Its Lessons for the Development of the Soybean Industry in China
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作者 Guancong Deng Tian Tian 《China's Foreign Trade》 2024年第1期47-50,共4页
Since the 1950s,China has gradually moved away from complete self-sufficiency in terms of soybeans to a high dependence on imports,and its annual import of soybeans accounts for about 60%of the global soybean trade.Br... Since the 1950s,China has gradually moved away from complete self-sufficiency in terms of soybeans to a high dependence on imports,and its annual import of soybeans accounts for about 60%of the global soybean trade.Brazil,the United States and Argentina have seen rapid growth in the soybean industry in just a few decades,and now account for about 80%of the world’s annual production.On the whole,in addition to the unique resource endowment and the continuous expansion of international market demand,the strong support of the U.S.government. 展开更多
关键词 SOYBEAN ent IMPORTS
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Evaluation of the Quality of Life of Patients Suffering from Chronic Rhinosinusitis in a Hospital Setting in Kinshasa
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作者 Hilaire K. Kalala Patricia K. Kakobo +3 位作者 Honoré N. Yalombe Lievin K. Mvita Léon N. Muamba Dieudonné T. Nyembue 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第1期41-52,共12页
Background and objective: Chronic rhinosinusitis (CRS), a common disease worldwide, has a major impact on patients’ quality of life (QoL). In recent years, the measurement of health-related QoL has made it possible t... Background and objective: Chronic rhinosinusitis (CRS), a common disease worldwide, has a major impact on patients’ quality of life (QoL). In recent years, the measurement of health-related QoL has made it possible to assess the patient’s state of health, the severity of the CRS and the treatment. The aim of this study was to assess the QoL of patients with CRS in a hospital setting in Kinshasa. Methods: This was a cross-sectional analytical study conducted from June 2020 to May 2021 in the ENT service of the Kinshasa University Hospital and the Monkole Hospital Center. The study involved 113 patients aged at least 18 years, whose QOL was compared with that of a control group consisting of 100 non-patients. QOL was assessed using the Sino-Nasal Outcome Test (SNOT-22) Questionnaire. Results: The mean age of the patients was 41.0 years (18 - 74 years) and that of the controls was 39.1 years (19 - 77 years). More than half of the participants were university graduates. The median SNOT-22 score was 44 (14 - 78) in patients and 7 (1 - 40) in controls. Compared with subjects without CRS, patients with CRS had significantly higher scores in all four domains of the SNOT-22. Around 9 out of 10 patients had a severely impaired QoL compared with 2 out of 10 controls. Considering mildly impaired QoL, we found that in the otological and sleep domains, scores were not significantly different between patients and controls. In the case of severely impaired QoL, however, only the otological domain showed a non-significant difference in scores between the two groups. Conclusion: CRS is a real public health problem in our environment and significantly alters the QoL of patients suffering from it, with repercussions on their professional productivity;hence the need for better management. 展开更多
关键词 Chronic Rhinosinusitis Quality of Life SNOT-22 ent KINSHASA
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基于MaxEnt模型预测伯乐树生境适宜性评价
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作者 吴晓昱 《智慧农业导刊》 2024年第7期21-26,共6页
该研究旨在预测伯乐树的适宜分布区并识别主导其分布的环境变量,为保护伯乐树资源提供理论依据。该研究使用ENMTools筛选出126个伯乐树分布点数据。应用MaxEnt模型,模拟4种环境变量组合,气候变量,气候和土壤变量,气候、土壤和紫外变量... 该研究旨在预测伯乐树的适宜分布区并识别主导其分布的环境变量,为保护伯乐树资源提供理论依据。该研究使用ENMTools筛选出126个伯乐树分布点数据。应用MaxEnt模型,模拟4种环境变量组合,气候变量,气候和土壤变量,气候、土壤和紫外变量及气候、土壤、紫外和地形综合变量。通过比较这4种模型的准确性和可靠性,探讨影响伯乐树分布的主要环境变量。基于4组环境变量的MaxEnt模型,AUC值训练集分别为0.973±0.001、0.973±0.001、0.975±0.001、0.977±0.001。结果表明,4类综合环境变量模拟模型最为稳定和可靠。伯乐树地理分布主要由气候(日温度平均范围、最干季度平均温度、最干月降水量)、土壤(基本饱和度、土壤有效水含量)、紫外(紫外线的季节性变化、紫外线最弱月份平均辐射量)、地形(高程)等4类综合环境变量影响。伯乐树的地理分布格局受多种环境因素的综合影响。4类环境变量模拟的结果更准确地反映了伯乐树的适宜分布区。该研究可为伯乐树遗传资源收集和种质资源保护提供重要的数据支持。 展开更多
关键词 伯乐树 Max ent AUC 环境变量 适宜分布区
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Stonehenge:A mysterious monument
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作者 吴汉茹 《疯狂英语(新悦读)》 2024年第9期47-48,77,共3页
Activity 1.Think about the following questions and write down your answers before reading the text.1.How do you feel when thinking about ancient monuments?2.Why do you think Stonehenge continues to fascinate people to... Activity 1.Think about the following questions and write down your answers before reading the text.1.How do you feel when thinking about ancient monuments?2.Why do you think Stonehenge continues to fascinate people today? 展开更多
关键词 CONTINUE ent STONE
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External Otitis: Epidemiological, Clinical, Etiological, and Therapeutic Aspects at the Oto-Rhino-Laryngology Department of Mamou Regional Hospital
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作者 Mamadou Mouctar Ramata Diallo Sayon Kourouma +6 位作者 Oumou Amadou Diallo Ibrahima Diallo Francine Haba Alsény Cisse Raphan Madi Kaba Keita Abdoulaye Keita Alpha Oumar Diallo 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第3期213-224,共12页
Introduction: External otitis (OE) is an acute or chronic inflammation or infection of the external ear resulting from an imbalance in the external auditory canal secondary to microtrauma, maceration, eczema, or a for... Introduction: External otitis (OE) is an acute or chronic inflammation or infection of the external ear resulting from an imbalance in the external auditory canal secondary to microtrauma, maceration, eczema, or a foreign body in the external auditory canal. Objective: To study cases of external otitis at the Mamou Regional Hospital. Materials and Methods: This was a prospective descriptive study conducted over a period of six (6) months from July 1st to December 31st, 2016. It included all patients admitted to the ENT department of the Mamou Regional Hospital. Results: During the study period, 712 patients were admitted to the department for various pathologies, of which 103 met our selection criteria, representing a frequency of 14.46%. The mean age of the patients was 33.74 years with a range of 1 to 90 years. Males predominated in the sample, accounting for 59.22%. The vast majority of patients resided in urban areas, constituting 61.17% of the sample. In our study, all patients consulted for otalgia (100%), and over half (53.39%) for hypoacusis. We formally identified rhinitis in 66.66% of cases, while diabetes was found in only 4 patients (11.11%). Otomycosis was the most commonly identified condition (53.39%), followed by furuncles (33.98%). Ear drops containing antibiotics were administered to all patients, although 66.60% received antibiotic therapy. Conclusion: External otitis is a relatively common condition, particularly among children and the elderly. Diagnosis can be made based on pain upon traction of the pinna and pressure on the tragus. 展开更多
关键词 External Otitis ent Mamou Regional Hospital
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Infectious ENT Emergencies: A One-Year Experience at the ENT Department of Mamou Regional Hospital
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作者 Mamadou Mouctar Ramata Diallo Ibrahima Diallo +5 位作者 Oumou Amadou Diallo Alsény Cisse Mamadou Bailo Sow Raphan Madi Kaba Keita Abdoulaye Keita Alpha Oumar Diallo 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第5期359-372,共14页
Introduction: ENT infectious emergencies encompass all infectious pathologies affecting the ear, nose, sinuses, throat, and neck. A good understanding of these emergencies is essential for organizing appropriate care.... Introduction: ENT infectious emergencies encompass all infectious pathologies affecting the ear, nose, sinuses, throat, and neck. A good understanding of these emergencies is essential for organizing appropriate care. In Guinea, few studies have described ENT infectious pathologies in rural areas. Objective: To study ENT infectious emergencies in the Otorhinolaryngology department of the Mamou Regional Hospital. Materials and Methods: This is a retrospective and prospective descriptive study, conducted from August 1, 2021, to July 31, 2022. All patients admitted to the ENT department of the Mamou Regional Hospital for an infectious emergency were included. Results: Among the 1854 recorded consultations, 261 cases involved ENT infectious emergencies, representing a prevalence of 14.07%. The most represented age group was 0 to 10 years (31.03%), with a majority of female patients (59%) and a predominantly urban origin (81.61%). Students accounted for 32.18% of the cases. The main reasons for consultation were odynophagia/dysphagia (32.42%) and otalgia (22.94%). The primary etiologies were tonsillitis (28.73%) and otitis (27.20%). Treatments administered included probabilistic antibiotic therapy (38.80%), analgesics (32.03%), and corticosteroid therapy (10.47%). The outcome was favorable in 98.85% of cases, with only 0.38% lost to follow-up. Conclusion: The results of our study confirm the frequency of ENT infectious pathologies. Their management requires joint actions for population awareness, staff training, and services equipment, particularly in rural areas. 展开更多
关键词 ent Infection Emergency Mamou Regional Hospital
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Otorhinolaryngological (ORL) and Cervicofacial Injuries Resulting from Road Accidents within the Otorhinolaryngology (ORL) Department of the Regional Hospital of Mamou
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作者 Mamadou Mouctar Ramata Diallo Ibrahima Diallo +8 位作者 Alsény Camara Mamadou Aliou Diallo Raphan Madi Kaba Keita Abdoulaye Sow Alsény Cisse Sory Sacko Mamadou Gouraissiou Diallo Abdoulaye Keita Alpha Oumar Diallo 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第1期16-28,共13页
Introduction: Otorhinolaryngological (ORL) and cervicofacial traumas encompass injuries affecting the neck, face, and ORL region, resulting from external influence. The objective of this study was to conduct an epidem... Introduction: Otorhinolaryngological (ORL) and cervicofacial traumas encompass injuries affecting the neck, face, and ORL region, resulting from external influence. The objective of this study was to conduct an epidemiological and clinical analysis of ORL and cervicofacial injuries observed in victims of road accidents treated at the Otorhinolaryngology (ORL) department of the Regional Hospital of Mamou. Materials and Methods: This prospective and descriptive study was conducted over a period of 12 months, from January 1st to December 31st, 2021, within the Otorhinolaryngology (ORL) department of the Regional Hospital of Mamou. It included patients hospitalized for ORL and/or cervicofacial traumas resulting from road accidents during the study period. Results: A total of 348 cases were included, representing 36.22% of all traumas related to road accidents (AVP) within the Regional Hospital of Mamou. The average age of the patients was 26.44 years, with a sex ratio of 3.83, favoring males. The dominant socio-professional category was students, encompassing 32.47% of cases. Road accidents were mainly associated with motorcycle use (31.32% motorcycle-to-motorcycle, 24.43% motorcycle skidding, 13.51% motorcycle-pedestrian). Facial region injuries were the most common, accounting for 69.03% of cases, followed by rhinological injuries (17.28%) and otological injuries (13.69%). Associated injuries were predominantly closed head traumas (52.55%) and lower limb fractures (20.41%). Imaging was underutilized. Regarding surgical interventions, reconstructive surgery was the most predominant, accounting for 52.51% of cases, with a management timeframe of 30 minutes to 12 hours for 99.72% of patients. Conclusion: Road traffic accidents remain a serious public health issue, primarily affecting young males. Emphasis should be placed on road safety measures to reduce the frequency of these accidents. 展开更多
关键词 ent Injuries Road Accidents Regional Hospital of Mamou
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基于MaxEnt分析金钱松适生的生物气候特征 被引量:44
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作者 王雷宏 杨俊仙 徐小牛 《林业科学》 EI CAS CSCD 北大核心 2015年第1期127-131,共5页
【目的】利用Max Ent模型分析金钱松适生的生物气候特征,为金钱松林业生产提供科学依据。【方法】从我国4个标本馆获取金钱松43个标本记录数据,并从World Clim网站下载1950—2000年生物气候数据,用最大熵模型(Max Ent)模拟金钱松的地... 【目的】利用Max Ent模型分析金钱松适生的生物气候特征,为金钱松林业生产提供科学依据。【方法】从我国4个标本馆获取金钱松43个标本记录数据,并从World Clim网站下载1950—2000年生物气候数据,用最大熵模型(Max Ent)模拟金钱松的地理分布,检测其生物气候主导因子及其适宜值。【结果】金钱松最适宜(分布值为0.73~1.0)分布的地区是湖南东部、湖北东南部、江西的东北部、安徽的南部、浙江西北部和其东部沿海地区,其余具分布值0.37~0.73的区域是以上这些高分布值区域的向外连续延伸。刀切法检测表明:冷季均温、干季均温、暖季降雨量对金钱松的分布影响较大,其中冷季均温适宜值为1.15~8.1℃,最适值为4.62℃;干季均温适宜值为2.7~11.9℃,最适值为7.3℃;暖季降雨量适宜值为45.6~734.4 mm,最适值为546.9 mm。【结论】Max Ent模拟可信度较高,精确反映出金钱松的地理分布范围,并阐明主导其分布的3个生物气候因子,揭示金钱松在地理分布上所需的定量生物气候条件。 展开更多
关键词 金钱松 MAX ent模型 生物气候
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Realization of Fully Differential Fourth-Order Bessel Filter with Accurate Group Delay 被引量:1
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作者 江金光 何怡刚 吴杰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第9期927-932,共6页
A fully differential R-MOSFET-C fourth-order Bessel active lowpass filter employing fully differential operational amplifier,passive resistors,and current-steering MOS transistors as a variable resistor is proposed.T... A fully differential R-MOSFET-C fourth-order Bessel active lowpass filter employing fully differential operational amplifier,passive resistors,and current-steering MOS transistors as a variable resistor is proposed.This proposed implementation relies on the tunability of current-steering MOS transistors operating in the triode region counteracting the concert deviation of resistor in the integrated circuit manufacturing technology in orde r that the group delay of Bessel active filter could be designed accurately.The amplifier is not only with voltage common-mode negative feedback,but also with current common-mode negative feedback,which will benefit for the stability of its D C operating point.0.75μs group delay fourth-order Bessel lowpass filter,whic h is synthesized according to passive doubly terminated RLC prototype lowpass filter,demonstrates better than -65dB THD using 100kHz,2.5V pp signal in Taiwan UMC 2P2M(2-poly,2-metal)5.0V,0.5μm CMOS technology. 展开更多
关键词 fully differential voltage and curr ent common-mode negative feedback frequency tunable R-MOSFET-C filter Bessel filter
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计算机辅助耳鼻喉科(ENT)手术中的组合配准方法 被引量:2
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作者 谌飚 庄天戈 StephaneLavallee 《中国生物医学工程学报》 EI CAS CSCD 北大核心 2000年第2期138-144,共7页
本文提出了在计算机辅助手术中基于解剖结构的组合式配准新方法。该方法将手术前病人皮肤和骨骼表面的三维模型与手术中来自三维定位器的采集数据 ,依据各自的特性进行最优匹配 ,并在耳鼻喉科 (ENT)手术中得到了精确可靠的结果。在新鲜... 本文提出了在计算机辅助手术中基于解剖结构的组合式配准新方法。该方法将手术前病人皮肤和骨骼表面的三维模型与手术中来自三维定位器的采集数据 ,依据各自的特性进行最优匹配 ,并在耳鼻喉科 (ENT)手术中得到了精确可靠的结果。在新鲜尸体样本上的实验表明 ,新的配准算法可应用于医学临床试验。同时对三维光学定位器的精度进行了测试 。 展开更多
关键词 图象配准 计算机辅助技术 耳鼻喉科 ent手术
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基于MaxEnt模型的四川小寨子沟国家级自然保护区大熊猫化学通讯位点适宜性评价 被引量:2
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作者 黎运喜 赵军 +6 位作者 李刚 贺飞 彭波 刘富文 朱云东 陈佑平 涂正彬 《四川动物》 北大核心 2018年第3期275-279,共5页
为揭示影响野生大熊猫Ailuropoda melanoleuca化学通讯位点选择的生态因素,于2016年3月和10月在四川小寨子沟国家级自然保护区,利用样线法对大熊猫化学通讯位点的适宜性进行了初步研究。调查共发现大熊猫化学通讯位点33个,基于这些位点... 为揭示影响野生大熊猫Ailuropoda melanoleuca化学通讯位点选择的生态因素,于2016年3月和10月在四川小寨子沟国家级自然保护区,利用样线法对大熊猫化学通讯位点的适宜性进行了初步研究。调查共发现大熊猫化学通讯位点33个,基于这些位点和海拔、坡度、竹林分布等10个环境变量,使用最大熵(Max Ent)模型对该区域大熊猫化学通讯位点适宜性进行综合评价。结果表明:竹林分布(56.90%)和距山脊距离(29.90%)2个环境变量的累积贡献率达86.80%,是影响该区域大熊猫化学通讯位点的主要生态因子。依据Max Ent模型最大约登指数,将结果分为适宜和不适宜2种类型,其中,适宜面积为15 187.50 hm^2,占研究区域面积的34.22%,主要位于保护区中部、保护区南北部分别与宝顶沟和白河自然保护区交界区域;不适宜面积为29 197.20 hm^2,占65.78%。在人力、物力有限的情况下,本研究为保护区合理安排保护行动的时段和区域、提升大熊猫的保护成效提供了数据支撑,对进一步推动野生大熊猫保护实践具有一定意义。 展开更多
关键词 大熊猫 化学通讯 适宜性 MAX ent模型 四川小寨子沟国家级自然保护区
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DH临床应用最新进展:ENT手术模拟器Voxel-Man TempoSurg 被引量:3
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作者 秦笃烈 《中国医疗器械信息》 2006年第6期59-61,共3页
医疗器械设备已经被大家公认,任何医院或者医学院都不可缺少。其用途往往和直接的临床活动有关。随着计算机技术、数字人(DH,Digital Human)技术以及材料技术的发展,各种手术模拟器也开始进入医疗器械设备的序列。
关键词 ent手术 模拟器 临床应用 医疗器械设备 Digital 计算机技术 临床活动 医学院 数字人
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化合物ent-kaur-16-en-19-oic acid的含量研究
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作者 钟长斌 魏露燕 李祥 《中医药导报》 2006年第1期67-68,共2页
目的:采用高效液相色谱法测定化合物ent-kaur-16-en-19-oic ac id在光叶番荔枝不同部位和番荔枝属不同种类植物叶子中的含量。方法:色谱条件为:Nuc leosil C18色谱柱,流动相选用乙睛:水(含1%冰醋酸)=67.5:32.5,检测波长211nm。结果:平... 目的:采用高效液相色谱法测定化合物ent-kaur-16-en-19-oic ac id在光叶番荔枝不同部位和番荔枝属不同种类植物叶子中的含量。方法:色谱条件为:Nuc leosil C18色谱柱,流动相选用乙睛:水(含1%冰醋酸)=67.5:32.5,检测波长211nm。结果:平均回收率为98.41%,光叶番荔枝树皮、光叶番荔枝树枝(去皮)、光叶番荔枝树叶、AP番荔枝树叶、牛心番荔枝树叶、山刺番荔枝树叶中化合物ent-kaur-16-en-19-oic ac id的含量分别为0.7147%、0.01252%、0.01773%、0.04212%、0.007305%、0.09083%。结论:在光叶番荔枝各部位中,树皮的含量最高,达0.7147%,在所测番荔枝属植物的树叶中,山刺番荔枝树叶中含量最高,达0.09083%。 展开更多
关键词 ent—kaur-16-en-19-oic ACID HPLC 含量测定
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基于MaxEnt模型的西伯利亚蝗虫在新疆潜在分布预测研究 被引量:22
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作者 杨会枫 郑江华 +3 位作者 吴秀兰 穆晨 林俊 许仲林 《新疆农业科学》 CAS CSCD 北大核心 2016年第1期43-50,共8页
【目的】利用MaxEnt模型,预测西伯利亚蝗虫(Gomphocerus sibiric)在新疆的潜在分布区。【方法】基于19个环境因子和197个西伯利亚蝗虫在新疆地理分布点,结合MaxEnt模型与ArcGIS软件,预测西伯利亚蝗虫在新疆的潜在分布区,划分风险等级,... 【目的】利用MaxEnt模型,预测西伯利亚蝗虫(Gomphocerus sibiric)在新疆的潜在分布区。【方法】基于19个环境因子和197个西伯利亚蝗虫在新疆地理分布点,结合MaxEnt模型与ArcGIS软件,预测西伯利亚蝗虫在新疆的潜在分布区,划分风险等级,采用接受者操作特征曲线(ROC)的分析方法对预测结果进行验证。【结果】训练数据集(Training data)和验证数据集(Testing data)的AUC值分别为0.992、0.990,预测结果与实际拟合度很高。西伯利亚蝗虫在新疆分布的适生区和高危区分布在塔城、阿勒泰、博州、伊犁、乌鲁木齐、昌吉。【结论】根据AUC值的评价指标,研究对西伯利亚蝗虫的预测结果是比较准确的。西伯利亚蝗虫在新疆分布的适生区和高危区主要集中于北疆及天山北坡一带,且适生区及高危区占研究区总面积的14.11%。最冷季平均温(bio11)、最冷季的平均降水量(bio19)、最干季平均温(bio9)、温度变化的方差(bio4)、年均降雨量(bio12)、最湿季平均温(bio8)和降雨量变化的方差(bio15)是影响西伯利亚蝗虫潜在分布的主要环境因子。 展开更多
关键词 西伯利亚蝗虫 MAX ent模型 潜在分布 预测
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基于MaxEnt模型的两种捕食性盲蝽潜在分布区及其适生性分析 被引量:17
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作者 祝梓杰 王桂瑶 +4 位作者 乔飞 白月亮 程家安 Kong Luen HEONG 祝增荣 《昆虫学报》 CAS CSCD 北大核心 2017年第3期335-346,共12页
【目的】为了预测和分析稻飞虱的两种重要捕食性天敌中华淡翅盲蝽Tytthus chinensis和黑肩绿盲蝽Cyrtorhinus lividipennis的潜在分布区,研究气候环境因素对其潜在分布的影响。【方法】Max Ent是以最大熵理论为基础的预测物种地理分布... 【目的】为了预测和分析稻飞虱的两种重要捕食性天敌中华淡翅盲蝽Tytthus chinensis和黑肩绿盲蝽Cyrtorhinus lividipennis的潜在分布区,研究气候环境因素对其潜在分布的影响。【方法】Max Ent是以最大熵理论为基础的预测物种地理分布的模型,本文运用Max Ent模型,根据这两种盲蝽的已知分布区及其气候环境影响因素,推测这两种盲蝽的适生性分布及气候环境因素的影响。【结果】中华淡翅盲蝽主要适宜分布区域为中国秦岭-淮河以南地区、东北亚的朝鲜半岛和日本、东南亚以及菲律宾和印度尼西亚群岛部分地区,即东洋区和大洋区北部群岛;黑肩绿盲蝽适宜分布区比中华淡翅盲蝽更广,可达山东、河北以南,陕西、云南、贵州以东的中国大部地区,海外除中华淡翅盲蝽分布区外,也可分布于南美亚马逊雨林地区。研究还发现,最热季度降雨量、平均日温差对中华淡翅盲蝽、黑肩绿盲蝽适宜性分布有重要影响;夏季降雨量大于500 mm、平均日温差低于10℃,有利于这两种盲蝽的分布。【结论】两种捕食性盲蝽适宜生境主要受最热季度降雨量、平均日温差影响。本研究为发挥这两种捕食性盲蝽在害虫生物防治中的作用提供了重要依据。 展开更多
关键词 中华淡翅盲蝽 黑肩绿盲蝽 分布 适生性分析 气候环境因素 MAX ent模型
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A New Integrated Design Method Based on Fuzzy Matter-Element Optimization 被引量:5
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作者 ZHAO Yan-wei 1, ZHANG Guo-xian 2 (1. College of Mechanical Engineering, Zhejiang University o f Technology, Hangzhou 310014, China 2. College of Mechanical & Electronic al Engineering, Shanghai University, Shanghai 200072, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期136-,共1页
This paper puts forward a new integrated design met ho d based on fuzzy matter-element optimization.On the based of analyzing the mod el of multi-objective fuzzy matter-element , the paper defines the m atter-element ... This paper puts forward a new integrated design met ho d based on fuzzy matter-element optimization.On the based of analyzing the mod el of multi-objective fuzzy matter-element , the paper defines the m atter-element weightily and changes solving multi-objective fuzzy optimization into solving dependent function K(x) of the single-objective optimization according to the optimization criterion. The paper particularly describes the realization approach of GA process of multi -objective fuzzy matter-element optimization: encode, produce initial populati on, confirm fitness function, select operator, etc. In the process, the adaptive macro genetic algorithms (AMGA) is applied to enhancing the evolution speed. Th e paper improves the two genetic operators: crossover and mutation operator. The modified adaptive macro genetic algorithms (MAMGA) is put forward simultane ously. It is adopted to solve the optimization problem. Three optimization methods, namely fuzzy matter-element optimization method, li nearity weighted method and fuzzy optimization method, are compared by using the table and figure, it shows that not only MAMGA is a little better than the AMGA , but also it reaches the extent to which the effective iteration generation is 62.2% of simple genetic algorithms (SGA). By the calculation of optimum exam ple, the improved method of genetic in the paper is much better than the method in reference of paper. 展开更多
关键词 multi-objective optimization fuzzy matter-elem ent genetic algorithms scheme design
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Use of the Max Ent model to predict changes in sloth bear(Melursus ursinus)habitats in the Gandaki River Basin,Nepal 被引量:2
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作者 Raju RAI ZHANG Yi-li +4 位作者 WANG Zhao-feng Basanta PAUDEL LIU Lin-shan Mohan Kumar RAI Narendra Raj KHANAL 《Journal of Mountain Science》 SCIE CSCD 2022年第7期1988-1997,共10页
The Gandaki River Basin(GRB),located in the central Himalaya,provides habitats for a large number of important flora and fauna species.The habitats of key protected species have changed over time as a result of climat... The Gandaki River Basin(GRB),located in the central Himalaya,provides habitats for a large number of important flora and fauna species.The habitats of key protected species have changed over time as a result of climate changes and human activities related to land use change,including the development of roads.This study assessed the present and future distributions of sloth bear(Melursus ursinus)habitats using the maximum entropy(Max Ent)model.Bioclimatic data,a digital elevation model and roads were used as environmental layers to assess current and future distributions of habitat.Results show that the overall habitat within the study area is likely to undergo important changes in the future.Bio 8(the mean temperature of the wettest quarter)and slope were found to be important variables affecting the distribution of the species.The habitats very highly suitable for sloth bears currently cover an area of 148 km^(2) within the GRB.These habitats are predicted to increase by 122 km^(2) more by 2050.Overall,a net change by 680.38 km^(2) was found in the GRB.Conservation measures are necessary for this key protected species and its habitat within the GRB and elsewhere in Nepal. 展开更多
关键词 Sloth bear Melursus ursinus Habitat prediction Max ent Gandaki River Basin Himalays
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