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资源定量评价发展方向展望

地球科学（中国地质大学学报） 2001年第2期26卷 152-156页

作者： donald a.singer 美国地质调查所

未来的资源定量评价希望能够评估未发现矿产资源的量、价值并对其进行定位预测 ,以能够表达矿产资源的经济潜力和不确定性 .近年来金属价格的长期下跌提出了对更大型的矿床的需求 .敏感度分析表明了减少评价中不确定性和风险的最有效途... 详细信息

未来的资源定量评价希望能够评估未发现矿产资源的量、价值并对其进行定位预测 ,以能够表达矿产资源的经济潜力和不确定性 .近年来金属价格的长期下跌提出了对更大型的矿床的需求 .敏感度分析表明了减少评价中不确定性和风险的最有效途径是降低有关吨位估计因素的不确定性 .到目前为止 ,在评价中所有可能造成误差的因素中 ,那些与吨位估计误差有关的因素是最重要的 .鉴于吨位模型的绝对重要地位以及矿床模型是吨位最有效的预测手段 ,正确地选择矿床模型是控制误差最重要的途径 .地表大部分地区被大面积裸露的岩石和沉积物所覆盖 .由于很多出露地表的矿床已经被发现 ,人们开始把注意力转向盖层下面岩石可能显露的矿化信息上 .这些区域的资源评价必需依靠对其周边地区的外推、地下覆盖岩石新的地质填图或者通过在其他成功勘探区获得的经验进行类推 .盖层对评价的不确定性以及评价的方法与程序都具有深远的影响 ,因为地下地质现象的不可见性和地球物理方法所获得的是一种被削弱了的信息 .许多早期的评价方法都是基于从那些出露地表的矿床中总结出的地球化学和地球物理变量之间的关系而进行的 ,而现在我们同样需要研究基于地下隐伏矿床的勘探经验 .矿床模型在资源定量评价中的重要地位基于以下两个原因 :(1)

关键词：矿床模型品位-吨位模型经济模型勘查风险矿产资源资源定量评价

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未被发现矿床规模的分布

地质科技情报 1991年第2期10卷 56-62页

作者： Chang-Jo F.Chung donald a.singer 王仁铎

未被发现矿床规模分布的知识在勘探计划和资源评价中起着极为重要的作用.当获悉诸已知矿床的发现顺序后,发现矿床的过程可归结为预测未知矿床的规模分布,正如在石油资源估计中所作的那样.然而对金属矿床来讲,除了特殊情况外,即便是确定... 详细信息

未被发现矿床规模分布的知识在勘探计划和资源评价中起着极为重要的作用.当获悉诸已知矿床的发现顺序后,发现矿床的过程可归结为预测未知矿床的规模分布,正如在石油资源估计中所作的那样.然而对金属矿床来讲,除了特殊情况外,即便是确定已知矿床的发现顺序也是很困难的.我们提出对未被发现矿床规模分布进行建模的一种新方法,是通过检查已知矿床规模的经验分布函数的性态来实现的.所建议的方法不要求知道已知矿床的发现顺序.众所周知,在一定条件下,某些分布函数的参数可根据这种经验分布函数的尾部估计出来.同样的技术已被应用于估计具有低于变量检测限的化学分析数据的痕量元素的分布函数了.将此法应用于美国加利福尼亚州硅质碳酸盐型矿床的数据集上,并将其结果与用通常的样本平均数和样本方差方法的结果进行了对比.

关键词：矿床分布规模

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利用矿物成分概率神经网络法进行矿床分类

地质科学译丛 1997年第1期14卷 61-62页

作者： donald a.singer 谢荣举 U.S.Geological Survey 345 Middlefield RoadMenlo ParkCalifornia 94205USA

为了进一步确定量化矿床模式是否令人满意,本文对利用矿物成分概率神经网络法进行矿床分类做了检验。典型类型矿床的矿石和蚀变矿物成分存在与否被用来训练神经网络。为了降低要考虑的矿物种类,只利用至少一类矿床中矿物区占20%以上的... 详细信息

为了进一步确定量化矿床模式是否令人满意,本文对利用矿物成分概率神经网络法进行矿床分类做了检验。典型类型矿床的矿石和蚀变矿物成分存在与否被用来训练神经网络。为了降低要考虑的矿物种类,只利用至少一类矿床中矿物区占20%以上的那些矿物。这一限制的好处在于单个或很少出现的矿物不会影响到正确分类结果。

关键词：矿床分类矿物成分概率神经网络法

A Lognormal Distribution of Metal Resources

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地球科学（中国地质大学学报） 2011年第2期36卷 201-208页

作者： donald A. singer U.S. Geological Survey 345 Middlefield Road Menlo Park California 94025 USA

For national or global resource estimation of frequencies of metals,a lognormal distribution has commonly been recommended but not adequately *** of frequencies of Cu,Zn,Pb,Ag,and Au contents of 1 984 well-explored mineral deposits display a poor fit to the lognormal *** the same metals plus Mo,Co,Nb2O3,and REE2O3 are grouped into 19 geologically defined deposit types,only eight of the 73 tests fail to be fit by lognormal distribution,and most of those failures are in two deposit types suggesting a problem with those *** of the mean and standard deviation of each of the metals in each of the deposit types are provided for modeling.

关键词：地质矿石矿产资源地球科学

ABCD^(2) risk score does not predict the presence of cerebral microemboli in patients with hyper-acute symptomatic critical carotid artery stenosis

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Stroke & Vascular Neurology 2017年第2期2卷 41-46页

作者： Mahmud Saedon Charles E Hutchinson Christopher H E Imray donald R J singer Warwick Medical School University of WarwickCoventryUK University Hospitals Coventry Warwickshire NHS Trust CoventryUK Fellowship of Postgraduate Medicine LondonUK Yale School of Medicine New HavenConnecticutUSA

Introduction:ABCD^(2) risk score and cerebral microemboli detected by transcranial Doppler(TCD)have been separately shown to the predict risk of recurrent acute *** studied whether ABCD2 risk score predicts cerebral microemboli in patients with hyper-acute symptomatic carotid artery *** and methods:We studied 206 patients presenting within 2 weeks of transient ischaemic attack or minor stroke and found to have critical carotid artery stenosis(≥50% ).86 patients(age 70±1(SEM:years),58 men,83 Caucasian)had evidence of microemboli;72(84% )of these underwent carotid endarterectomy(CEA).120 patients(age 72±1 years,91 men,113 Caucasian)did not have microemboli detected;102(85% )of these underwent *** were analysed using X2 and Mann–Whitney U tests and receiver operating characteristic(ROC)***:140/206(68% :95% CI 61.63 to 74.37)patients with hyper-acute symptomatic critical carotid stenosis had an ABCD2 risk score≥*** was no significant difference in the NICE red flag criterion for early assessment(ABCD^(2) risk score≥4)for patients with cerebral microemboli versus those without microemboli(59/86 vs 81/120 patients:OR 1.05 ABCD2 risk score≥4(95% CI 0.58 to 1.90,p=0.867)).The ABCD2 risk score was<4 in 27 of 86(31% :95% CI 21 to 41)embolising patients and in 39 of 120(31% :95% CI 23 to 39)without cerebral *** adjusting for pre-neurological event antiplatelet treatment(APT),area under the curve(AUC)of ROC for ABCD2 risk score showed no prediction of cerebral microemboli(no pre-event APT,n=57:AUC 0.45(95% CI 0.29 to 0.60,p=0.531);preevent APT,n=147:AUC 0.51(95% CI 0.42 to 0.60,p=0.804)).Conclusions:The ABCD2 score did not predict the presence of cerebral microemboli or carotid disease in over one-quarter of patients with symptomatic critical carotid artery *** the basis of NICE guidelines(refer early if ABCD2≥4),assessment of high stroke risk based on ABCD2 scoring may lead to inappropriate delay in urgent treat

关键词： patients cerebral emboli

Development, coinfection, and the syndemics of pregnancy in Sub-Saharan Africa

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Infectious Diseases of Poverty 2013年第1期2卷 213-222页

作者： Merrill singer Department of Anthropology and Department of Community Medicine University of ConnecticutStorrsCT 06269USA

Notable among gaps in the achievement of the global health Millennium Development Goals(MDG)are shortcomings in addressing maternal health,an issue addressed in the fifth *** shortfall is particularly acute in Sub-Saharan Africa(SSA),where over half of all maternal deaths occur each *** there is not as yet a comprehensive understanding of the biological and social causes of maternal death in SSA,it is evident that poverty,gendered economic marginalization,social disruptions,hindered access to care,unevenness in the quality of care,illegal and clandestine abortions,and infections are all critical *** these factors,this paper presents a review of the existing literature on maternal health in SSA to argue that syndemics constitute a significant additional source of maternal morbidity and mortality in the *** focus on the nature,prevention,and treatment of syndemics,as a result,should be part and parcel of improving maternal health in SSA.

关键词： Syndemics Coinfection Maternal health Sub-Saharan Africa Millennium development goals

Registry report on prediction by Pocock cardiovascular score of cerebral microemboli acutely following carotid endarterectomy

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Stroke & Vascular Neurology 2018年第3期3卷 147-152页

作者： Mahmud Saedon Athanasios Saratzis Rachel W S Lee Charles E Hutchinson Christopher H E Imray donald R J singer Nottingham University Hospitals NHS Trust NottinghamUK University Hospitals Coventry and Warwickshire NHS Trust CoventryUK Leicester Royal Infirmary LeicesterUK Yale School of Medicine New HavenConnecticutUSA Fellowship of Postgraduate Medicine LondonUK

background Cerebral microemboli may lead to ischaemic neurological complications after carotid endarterectomy(CEA).The association between classical cardiovascular risk factors and acute cerebral microemboli following carotid surgery has not been *** aim of this study was to explore whether an established cardiovascular risk score(Pocock score)predicts the presence of cerebral microemboli acutely after *** and methods Pocock scores were assessed for the 670 patients from the Carotid Surgery Registry(age 71±1(SEM)years,474(71%)male,652(97%)Caucasian)managed from January 2002 to December 2012 in the Regional Vascular Centre at University Hospitals Coventry and Warwickshire NHS Trust,which serves a population of *** was undertaken in 474(71%)patients for symptomatic carotid stenosis and in 196(25%)asymptomatic patients during the same period.74% of patients were hypertensive,71%were smokers and 49% had *** A high Pocock score(≥2.3%)was significantly associated with evidence of cerebral microemboli acutely following CEA(P=0.039,Mann-Whitney(MW)test).A Pocock score(≥2.3%)did not predict patients who required additional antiplatelet therapy(microemboli signal(MES)rate>50 hour-1:P=0.164,MW test).Receiver operating characteristic analysis also showed that the Pocock score predicts acute postoperative microemboli(area under the curve(AUC)0.546,95%CI 0.502 to 0.590,P=0.039)but not a high rate of postoperative microemboli(MES>50 hour−1:AUC 0.546,95% CI 0.482 to 0.610,P=0.164).A Pocock score≥2.3% showed a sensitivity of 74% for the presence of acute postoperative cerebral microemboli.A Pocock score≥2.3% also showed a sensitivity of 77% and a negative predictive value of 90% for patients who developed a high microembolic rate>50 hour−1 after carotid *** These findings demonstrate that the Pocock score could be used as a clinical tool to identify patients at high risk of developing acute postoperative microemboli.

关键词： cerebral Surgery Registry

Evaluation of suprachiasmatic nucleus in Alzheimer’s disease with non-invasive magnetic resonance methods

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Neural Regeneration Research 2022年第8期17卷 1753-1754页

作者： Rico singer A.Alia Leiden Institute of Chemistry Leiden UniversityLeidenThe Netherlands Institute of Medical Physics and Biophysics University of LeipzigLeipzigGermany

The suprachiasmatic nucleus and Alzheimer’s disease(AD):AD is the most frequently diagnosed form of dementia,with the total number of AD patients worldwide expected to triple by 2050 compared to 2015(Prince et al.,2015).Despite years of research,much of the AD pathology remains unclear with no treatment or cure *** its two hallmarks,amyloid-β(Aβ)plagues and hyperphosphorylated tau tangles,a distortion of circadian rhythms is commonly ***,poor sleep quality or trouble falling asleep are common AD symptoms,sometimes developing 10-15 years before cognitive symptoms associated with AD(Ju et al.,2014).

关键词： al. Alzheimer supra

Intercalibration of 40Ar/39Ar laboratories in China, the USA and Russia for Emeishan volcanism and the Guadalupian–Lopingian boundary

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National Science Review 2019年第4期6卷 614-616页

作者： Brian R.Jicha Brad S.singer Youjuan Li Department of Geoscience University of Wisconsin-Madison State Key laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration

Precise geochronology is essential for constraining rates of sedimentary,biotic, climatic and magmatic processes over a wide range of timescales throughout Earth’s history. Targets for high-precision geochronology include lava flows or minerals from volcanic tuffs that are interbedded within sedimentary strata. High-precision dates from these materials commonly provide temporal anchors, allow disparate stratigraphic records to be correlated with one an-

关键词： the USA and Russia for Emeishan volcanism and the Guadalupian Ar laboratories in China Intercalibration of Ar Lopingian boundary USA