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Addressing schistosomiasis in the Philippines: Need for a coordinated intersectoral effort
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作者 Alvin I.Abeleda Don Eliseo Lucero-PrisnoⅢ Jerico B.Ogaya 《Asian Pacific Journal of Tropical Medicine》 2025年第5期239-240,共2页
To the Editor:Abeleda et al.[1]recently argued in a perspective article that the Philippines should do better in order to achieve its goal of reducing schistosomiasis incidence to zero in humans,animals,and snails by ... To the Editor:Abeleda et al.[1]recently argued in a perspective article that the Philippines should do better in order to achieve its goal of reducing schistosomiasis incidence to zero in humans,animals,and snails by 2025[2,3].The authors appropriately ascribed the need to ramp up surveillance,WASH(water,sanitation,and hygiene),and veterinary efforts.In this letter,I would like to add to the discussion that the key to achieving schistosomiasis elimination may be strengthening the veterinary public health sector and framing mitigation efforts within the One Health lens.Schistosoma(S.)japonicum infection is a zoonotic disease and it affects more than 40 species of animals,including livestock animals like cattle,pigs,and water buffaloes,and pets like dogs[4].In the Philippines,the prevalence of infection in animal reservoirs remains largely unknown in most endemic areas due to the lack of concerted epidemiological efforts unlike what is being done in human hosts.In areas where studies have been done,infection rates are from less than 10%to 97%in water buffaloes tested[5-7].Indeed,as Abeleda et al.[1]argued,there is a need to do better on this front. 展开更多
关键词 SCHISTOSOMIASIS Epidemiological Efforts Veterinary Public Health Water Buffaloes Zoonotic Disease One Health Animal Reservoirs strengthening veterinary public health sect
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Developing Hybrid XGBoost Model to Predict the Strength of Polypropylene and Straw Fibers Reinforced Cemented Paste Backfill and Interpretability Insights
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作者 Yingui Qiu Enming Li +2 位作者 Pablo Segarra Bin Xi Jian Zhou 《Computer Modeling in Engineering & Sciences》 2025年第8期1607-1629,共23页
With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.T... With the growing demand for sustainable development in the mining industry,cemented paste backfill(CPB)materials,primarily composed of tailings,play a crucial role in mine backfilling and underground support systems.To enhance the mechanical properties of CPB materials,fiber reinforcement technology has gradually gained attention,though challenges remain in predicting its performance.This study develops a hybrid model based on the adaptive equilibrium optimizer(adap-EO)-enhanced XGBoost method for accurately predicting the uniaxial compressive strength of fiber-reinforced CPB.Through systematic comparison with various other machine learning methods,results demonstrate that the proposed hybridmodel exhibits excellent predictive performance on the test set,achieving a coefficient of determination(R^(2))of 0.9675,root mean square error(RMSE)of 0.6084,and mean absolute error(MAE)of 0.4620.Input importance analysis reveals that cement-tailings ratio,curing time,and concentration are the three most critical factors affectingmaterial strength,with cement-tailings ratio showing a positive correlation with strength,concentrations above 70% significantly improvingmaterial strength,and curing periods beyond 28 days being essential for strength development.Fiber parameters contribute secondarily but notably to material strength,with fiber length exhibiting an optimal range of approximately 12 mm.This study not only provides a high-precision strength prediction model but also reveals the inherent correlations between various parameters and material performance,offering scientific basis for mixture optimization and engineering applications of fiber-reinforced CPB materials. 展开更多
关键词 Cemented paste backfill fiber-enhanced compressive strength prediction XGBoost adap-EO algorithm SHAP
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Detailed in-depth mapping of the world largest anorthositic complex:Magnetic anomalies,2.5-3D modelling and emplacement constraints of the Kunene Complex(KC),SW Angola
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作者 T.Mochales E.Merino-Martínez +11 位作者 C.Rey-Moral A.Machadinho J.Carvalho P.Represas J.L.García-Lobón M.C.Feria R.Martín-Banda M.T.López-Bahut D.Alves E.Ramalho J.Manuel D.Cordeiro 《Geoscience Frontiers》 2025年第3期261-285,共25页
The Kunene Complex(KC)represents a very large Mesoproterozoic igneous body,mainly composed of anorthosites and gabbroic rocks that extends from SW Angola to NW Namibia(outcropping 18,000 km^(2),NE-SW trend,and ca.350 ... The Kunene Complex(KC)represents a very large Mesoproterozoic igneous body,mainly composed of anorthosites and gabbroic rocks that extends from SW Angola to NW Namibia(outcropping 18,000 km^(2),NE-SW trend,and ca.350 km long and up to 50 km wide).Little is known about its structure at depth.Here,we use recently acquired aerogeophysical data to accurately determine its hidden extent and to unravel its morphology at depth.These data have been interpreted and modelled to investigate the unexposed KC boundaries,reconstructing the upper crustal structure(between 0 and 15 km depth)overlain by the thin sedimentary cover of the Kalahari Basin.The modelling reveals that the KC was emplaced in the upper crust and extends in depth up to ca.5 km,showing a lobular geometry and following a large NE-SW to NNE-SSW linear trend,presumably inherited from older Paleoproterozoic structures.The lateral continuation of the KC to the east(between 50 and 125 km)beneath the Kalahari Cenozoic sediments suggests an overall size three times the outcropping dimension(about 53,500 km^(2)).This affirmation clearly reinforces the economic potential of this massif,related to the prospecting of raw materials and certain types of economic mineralization(Fe-Ti oxides,metallic sulphides or platinum group minerals).Up to 11 lobes have been isolated with dimensions ranging from 135.5 to 37.3 km in length and 81.9 to 20.7 km in width according to remanent bodies revealed by TMI mapping.A total volume of 65,184 km3 was calculated only for the magnetically remanent bodies of the KC.A long-lasting complex contractional regime,where large strike-slip fault systems were involved,occurred in three kinematic pulses potentially related to a change of velocity or convergence angle acting on previous Paleoproterozoic inherited sutures.The coalescent magmatic pulses can be recognized by means of magnetic anomalies,age of the bodies as well as the lineations inferred in this work:(i)Emplacement of the eastern mafic bodies and granites in a stage of significant lateral extension in a transtensional context between 1500 Ma and 1420 Ma;(ii)Migration of the mantle derived magmas westwards with deformation in a complex contractional setting with shearing structures involving western KC bodies and basement from 1415 Ma to 1340 Ma;(iii)NNW-SSE extensional structures are relocated westwards,involving mantle magmas,negative flower structures and depression that led to the formation of late Mesoproterozoic basins from 1325 Ma to 1170 Ma.Additionally,we detect several first and second order structures to place the structuring of the KC in a craton-scale context in relation to the crustal structures detected in NW Namibia. 展开更多
关键词 ANGOLA Kunene Complex(KC) Magnetic prospecting 2.5 modelling 3D inversion
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贵州正安县奥陶系—志留系界线碳质泥岩Re-Os同位素精确厘定及其古环境反演 被引量:6
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作者 李欣尉 李超 +1 位作者 周利敏 赵鸿 《岩矿测试》 CAS CSCD 北大核心 2020年第2期251-261,共11页
我国上扬子地台地区在奥陶系—志留系之交广泛发育蕴含丰富页岩气资源的五峰组—龙马溪组富有机质沉积岩。采用Re-Os同位素体系对该套沉积地层进行研究,不仅能得到精确的地层沉积年龄,同时根据Re、Os元素的富集机制,对该时期沉积环境进... 我国上扬子地台地区在奥陶系—志留系之交广泛发育蕴含丰富页岩气资源的五峰组—龙马溪组富有机质沉积岩。采用Re-Os同位素体系对该套沉积地层进行研究,不仅能得到精确的地层沉积年龄,同时根据Re、Os元素的富集机制,对该时期沉积环境进行有效反演,可以为这一阶段发生的地球历史上第二大规模的生物绝灭事件的触发机制提供更合理的解释。本文在贵州正安县班竹1井岩心采集11件碳质泥岩样品,岩心样品连续且完整跨越奥陶系五峰组—志留系龙马溪组界线地层,通过对该样品开展高精度Re-Os同位素研究,获得了奥陶系—志留系地层界线Re-Os同位素年龄为443.68±6.24Ma[2σ,n=7,(187 Os/188 Os)i=0.699±0.019,MSWD=0.55],其结果与国际地层委员会发布的年龄(443.7±1.5Ma)高度一致,为奥陶系—志留系界线年龄提供了直接、准确的年龄依据。Os同位素特征反映了大量陆源碎屑参与成岩过程、多期火山活动的发生及冰期向间冰期的转换。连续沉积地层Re-Os同位素特征的变化反映了研究区奥陶系五峰组—志留系龙马溪组沉积环境经历富氧—缺氧—富氧的变化,指示赫南特期冰川事件和火山喷发共同造成了生物大绝灭并促进了有机质的富集,为五峰组—龙马溪组富有机质沉积岩提供了生烃潜力。 展开更多
关键词 RE-OS同位素定年 奥陶系—志留系界线 Os同位素特征 古环境演化 五峰组—龙马溪组富有机质沉积岩 热电离质谱法
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Addressing schistosomiasis in the Philippines:Need for a coordinated intersectoral effort
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作者 Alvin I.Abeleda Don Eliseo Lucero-PrisnoⅢ Jerico B.Ogaya 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第11期479-480,共2页
The World Health Organization(WHO)recognized schistosomiasis as one of the neglected tropical diseases(NTDs)caused by parasitic blood flukes.With a 4.68%national prevalence in 2017,schistosomiasis is endemic in 28 pro... The World Health Organization(WHO)recognized schistosomiasis as one of the neglected tropical diseases(NTDs)caused by parasitic blood flukes.With a 4.68%national prevalence in 2017,schistosomiasis is endemic in 28 provinces in the Philippines[1,2].Having agriculture as a common source of livelihood,the country is vulnerable to schistosomiasis as this disease is transmitted when a larva,released by freshwater snails,penetrates the skin of a susceptible individual.In fact,it was estimated that 12.4 million Filipinos are at risk,while 2.7 million are directly exposed to the parasite[2].This remains to be a major public health concern as it contributes to a considerable morbidity and mortality.In children,this disease causes malnutrition and impaired cognitive development.Globally,schistosomiasis as an NTD puts the burden on poverty-stricken areas,especially in low-and middle-income countries,exacerbating the health inequality within a country and across the globe. 展开更多
关键词 SCHISTOSOMIASIS IMPAIRED INCOME
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富碳质地质样品Re-Os同位素体系研究进展 被引量:3
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作者 李欣尉 李超 +2 位作者 周利敏 赵鸿 屈文俊 《岩矿测试》 CAS CSCD 北大核心 2023年第2期221-238,共18页
Re-Os同位素定年技术在富有机质沉积岩、低变质沉积岩、湖相沉积物、煤、油气藏样品等富碳质地质样品的尝试和成功应用,使其成为直接厘定地层沉积时代、重大地质事件发生时限和机制、古环境重建、油气藏直接定年、油气演化过程推演等研... Re-Os同位素定年技术在富有机质沉积岩、低变质沉积岩、湖相沉积物、煤、油气藏样品等富碳质地质样品的尝试和成功应用,使其成为直接厘定地层沉积时代、重大地质事件发生时限和机制、古环境重建、油气藏直接定年、油气演化过程推演等研究的关键技术手段。然而,受到富碳质地质样品中极低的Re和Os丰度、采样方式以及地质作用等因素的影响,很多样品的Re-Os等时线年龄和初始Os同位素比值精度超过10%,不能有效地评价海水Os的真实来源和地质作用程度,影响了对不同沉积体系及油气演化过程中Re和Os的化学行为和Re-Os等时线年龄地质意义的理解。由此,本文从富碳质地质样品的Re-Os化学行为和地质应用进展出发,对富碳质地质样品Re-Os同位素分析过程中的采样和取样方式、溶样方法、分离富集方式和标准物质选择四方面进行了总结和完善。指出以沉积速率为采样间距参考,通过预处理方式提高样品的均匀性,使用流程空白更低、对同位素分馏影响更小的溶样方法和分离富集方式进行Re-Os同位素分析,以基质匹配的地质标样进行数据监控可进一步提高样品Re-Os同位素分析质量,有助于不同类型富碳质地质样品Re和Os赋存机制研究、Re-Os同位素分析技术开发及地质应用拓展。 展开更多
关键词 RE-OS同位素体系 富碳质地质样品 油气演化 Re、Os化学行为 地质应用 富碳质地质标样
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蒸馏法富集纯化Os实验条件研究及其在负离子热电离质谱测量中的应用 被引量:1
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作者 李欣尉 杨显德 +2 位作者 李超 周利敏 赵鸿 《岩矿测试》 CAS CSCD 北大核心 2018年第4期439-447,共9页
微蒸馏是富集纯化Os的一项重要化学前处理技术,提高Os回收率对提高Os的负离子热电离质谱(NTIMS)测量精度尤为重要。在微蒸馏过程中,蒸馏温度、吸收液体积、蒸馏时间等对Os回收率具有重要影响,但目前微蒸馏的实验条件不够明确,导致Os回... 微蒸馏是富集纯化Os的一项重要化学前处理技术,提高Os回收率对提高Os的负离子热电离质谱(NTIMS)测量精度尤为重要。在微蒸馏过程中,蒸馏温度、吸收液体积、蒸馏时间等对Os回收率具有重要影响,但目前微蒸馏的实验条件不够明确,导致Os回收率不稳定,影响NTIMS测量精度,易增加所得Re-Os年龄误差。本文以自制的含Os溶液为对象,以ICP-MS为测量手段,对微蒸馏过程中多种实验条件对Os回收率的影响进行深入研究,以期获得最佳微蒸馏实验条件,满足后续NTIMS对Os信号强度的测量要求。结果表明:在溶液蒸干温度为120℃并保持15 min,微蒸馏温度为80℃,氢溴酸吸收液体积为15μL,微蒸馏时间为2 h的条件下,获得Os回收率为80%~90%,能够满足多种地质样品尤其是中酸性岩浆岩、热液硫化物等pg级地质样品的NTIMS测量要求,在保证Os信号强度的情况下提高了分析效率。 展开更多
关键词 负离子热电离质谱 微蒸馏最佳实验条件 Os回收率 Os富集纯化
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沥青Re-Os同位素年龄地质意义解读 被引量:6
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作者 李超 孙鹏程 +5 位作者 孟会明 王登红 周利敏 李欣尉 赵鸿 屈文俊 《岩石学报》 SCIE EI CAS CSCD 北大核心 2022年第6期1595-1604,共10页
Re、Os亲有机质的特性使得Re-Os同位素在富有机质地质样品中得到了广泛应用;沥青由大量重组分有机质组成,对Re、Os具有较强的富集能力,并且沥青样品中Re-Os同位素封闭性较好,因此沥青Re-Os同位素已经成为当今国际上研究的一个热点。然而... Re、Os亲有机质的特性使得Re-Os同位素在富有机质地质样品中得到了广泛应用;沥青由大量重组分有机质组成,对Re、Os具有较强的富集能力,并且沥青样品中Re-Os同位素封闭性较好,因此沥青Re-Os同位素已经成为当今国际上研究的一个热点。然而,沥青Re-Os同位素年龄究竟是代表烃源岩的沉积时代、油气成藏时代、还是油气藏破坏后油气运移时代,至今还没有明确的定论。本文对新疆乌尔禾沥青矿、四川矿山梁沥青矿样品进行了Re-Os同位素分析,结果显示,乌尔禾沥青矿Re-Os同位素年龄为269±9Ma,老于周围白垩系砂岩地层沉积时代,Os同位素初始比值^(187) Os/^(188 )Os(Os i)为0.367±0.028,小于二叠纪海水的Os i同位素比值,表明得到的乌尔禾沥青Re-Os同位素年龄反映的是乌尔禾油气藏的成藏时代。矿山梁沥青矿Re-Os同位素年龄为537.3±5.2Ma,老于围岩(寒武系、奥陶系、志留系地层)沉积时代,Os同位素初始比值为0.716±0.028,与早寒武世海水的Os_(i)同位素比值一致,表明得到的矿山梁沥青Re-Os同位素年龄代表烃源岩的沉积时代。结合前人发表的沥青Re-Os同位素数据,沥青Re-Os同位素等时线年龄可能反映烃源岩的沉积时代,也可能代表油气藏的形成时代,这主要取决于油气成藏过程中,具有不同Re-Os同位素特征的原油是否能够混合均匀。沥青Re-Os同位素年龄能否反映油气藏遭受破坏而发生运移的时代,主要取决于沥青的热演化程度以及油气藏破坏过程中原油的混合程度。沥青Re-Os同位素研究不仅能够为油气成藏时代的厘定提供了一种有力的工具,而且对于油气烃源岩的判别以及油气成因研究都具有十分重要的意义。 展开更多
关键词 沥青 RE-OS 同位素 年代学 油气藏 定年
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Os水吸收液ICP-MS测量信号强度衰减原因研究 被引量:2
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作者 周利敏 李超 +3 位作者 李欣尉 赵鸿 屈文俊 杜安道 《岩矿测试》 CAS CSCD 北大核心 2018年第4期431-438,346,共9页
蒸馏法能从样品中有效分离出OsO_4,吸收液直接用于ICP-MS测定,是辉钼矿Re-Os定年的关键技术环节。但实验发现,长时间放置的吸收液中Os信号强度显著降低。根据OsO_4化学性质推测原因在于一是挥发使吸收液Os含量减少,二是还原使+8价Os变... 蒸馏法能从样品中有效分离出OsO_4,吸收液直接用于ICP-MS测定,是辉钼矿Re-Os定年的关键技术环节。但实验发现,长时间放置的吸收液中Os信号强度显著降低。根据OsO_4化学性质推测原因在于一是挥发使吸收液Os含量减少,二是还原使+8价Os变成低价态,气态比例降低,若雾化效率不变,进入质谱仪的Os减少,两者都会导致信号降低,但具体影响情况不明,需深入研究。本文利用辉钼矿标准物质制备不同放置时间、酸度和温度的吸收液,对比上述条件对ICP-MS信号强度的影响。实验时将残余吸收液与稀释剂、氧化剂封入Carius管加热蒸馏,测定Os含量。结果表明:吸收液放置时间越长,酸度越低,温度越高,信号降幅越大,幅度达到3.2%~68.6%。室温下放置相同时间,低酸度吸收液的Os保存率高于高酸度吸收液,但Os信号强度低于后者,证明了挥发和还原共同导致信号衰减,且还原是主导原因。本文提出,冷冻(-18℃)可抑制OsO_4挥发,提高酸度(约3.5 mol/L)可减弱OsO_4还原,两者结合抑制信号衰减,提高了蒸馏法的灵活性和适用性。 展开更多
关键词 RE-OS同位素 蒸馏法 电感耦合等离子体质谱法 挥发作用 还原作用
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Insights into the microstructural design of high-performance Ti alloys for laser powder bed fusion by tailoring columnar prior-βgrains andα-Ti morphology
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作者 S.X.Wang S.F.Li +4 位作者 X.M.Gan R.D.K.Misra R.Zheng K.Kondoh Y.F.Yang 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第20期156-168,共13页
A high-performance Ti-Ni-B alloy with good tensile properties and reduced mechanical anisotropy was developed by promoting the columnar to equiaxed transition(CET)of prior-βgrains and modifyingα-laths to equiaxed gr... A high-performance Ti-Ni-B alloy with good tensile properties and reduced mechanical anisotropy was developed by promoting the columnar to equiaxed transition(CET)of prior-βgrains and modifyingα-laths to equiaxed grains.Both Ni and B contributed to the refinement of columnar prior-βgrains during the L→βphase transformation by generating constitutional undercooling.Compared with Ni,B had a su-perior capability of generating constitutional undercooling,which not only replaced a significant amount of Ni with a minor addition to reduce the formation of brittle eutectoid,but also reacted with Ti to form TiB to promote heterogeneous nucleation ofα-Ti grains during theβ→αphase transformation.Together with the restricted growth ofα-laths induced by the refinement of prior-βgrains,a fully equiaxedα-Ti structure was obtained.The competition between the negative effect of brittle eutectoid and the positive role ofα-lath to equiaxed grain transition on the ductility of as-printed Ti-Ni-B alloys was fundamen-tally governed by the morphology of eutectoid and technically dependent on the Ni-B content.When the addition was 1.2Ni-0.06B(wt.%)or less,the positive effect ofα-lath on equiaxed grain transition can effectively mitigate the issue of reduced ductility caused by brittle eutectoid.In contrast,at 1.8Ni-0.09B or greater,the negative effect of eutectoid dominated.New insights into microstructural design obtained through the aforementioned approach were presented and discussed. 展开更多
关键词 Laser powder bed fusion Titanium alloys Grain refinement Powder processing Anisotropy
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云南金顶铅锌矿成矿时代厘定:来自沥青Re-Os同位素证据 被引量:9
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作者 孙鹏程 李超 +7 位作者 周利敏 屈文俊 王登红 高兰 李伟 李欣尉 赵鸿 杜安道 《地球科学》 EI CAS CSCD 北大核心 2021年第12期4247-4259,共13页
MVT型铅锌矿由于成矿温度低,目前没有发现十分合适的定年矿物,此外,由于多期成矿作用叠加以及成矿物质存在多元混合,严重制约了对此类矿床成矿年代学研究.前人对云南金顶超大型MVT铅锌矿床成因、物质来源、成矿条件等方面研究取得了重... MVT型铅锌矿由于成矿温度低,目前没有发现十分合适的定年矿物,此外,由于多期成矿作用叠加以及成矿物质存在多元混合,严重制约了对此类矿床成矿年代学研究.前人对云南金顶超大型MVT铅锌矿床成因、物质来源、成矿条件等方面研究取得了重要成果,但对其形成时代各有所云,至今仍未定论.笔者在总结了大量前人研究成果的基础上,通过对跑马坪和架崖山矿段沥青样品开展Re-Os同位素定年研究,表明古油藏形成于59.1 Ma,金顶铅锌矿床的形成时代可能为27.7 Ma.早期的油气藏为后期铅锌矿的形成提供了十分重要的条件,穹隆构造为金属成矿提供了储矿空间,由于遭受构造及热液作用的破坏,油气裂解释放大量的还原性物质,为Pb、Zn等成矿物质迁移、富集、沉淀提供了重要载体,进而形成了金顶超大型铅锌矿床.研究结果表明,沥青Re-Os同位素不仅能够为MVT型铅锌矿床成矿年龄的厘定提供一种有效的技术途径,同时还能够为油气藏的生成、破坏等事件发生时代提供有利依据. 展开更多
关键词 MVT型铅锌矿 RE-OS 成矿时代 动力学背景 沥青 矿床
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滇中昆阳磷矿成矿时代及沉积环境Re-Os同位素示踪研究 被引量:8
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作者 严清高 李超 +3 位作者 江小均 王忠强 李云驹 李伟 《岩矿测试》 CAS CSCD 北大核心 2018年第4期462-474,共13页
川滇黔地区下寒武地层中广泛分布一系列磷矿床,其中滇中昆阳磷矿是我国下寒武统梅树村期黑色页岩中规模最大的海相沉积型磷矿床,其成矿时代以及沉积环境对于矿床成因研究以及区域找矿具有重要意义。Re-Os同位素不仅能够对富有机质沉积... 川滇黔地区下寒武地层中广泛分布一系列磷矿床,其中滇中昆阳磷矿是我国下寒武统梅树村期黑色页岩中规模最大的海相沉积型磷矿床,其成矿时代以及沉积环境对于矿床成因研究以及区域找矿具有重要意义。Re-Os同位素不仅能够对富有机质沉积岩地层进行直接定年,而且还能为物质来源及沉积环境示踪提供一种有效的技术手段。本文对昆阳磷矿中谊村段磷块岩和石岩头段黑色页岩开展热表面电离质谱法Re-Os同位素示踪及定年探索性研究,获得了石岩头段黑色页岩Re-Os等时线年龄为521.9±5.4Ma,直接限定了昆阳磷矿黑色页岩沉积时代。磷块岩187Os/188Os初始比值为0.6576~0.7671,黑色页岩187Os/188Os初始比值为0.887,另外磷块岩187Re/188Os值为2.582~240.5,而上覆黑色页岩187Re/188Os值为96.24~341.8,而且磷块岩、黑色页岩微量元素δEu和δCe值在垂向剖面上显示由低变高的变化特征,这些证据表明昆阳磷矿形成正处于大陆快速剥蚀时期,指示大量陆源碎屑汇入海洋参与成岩-成矿过程。综合前人研究,本文认为,在寒武纪,大气氧含量快速升高,加剧陆壳风化,大量高放射性陆源Os的输入造成该时期内187Os/188Os初始比值逐渐升高。另外由于全球海平面上升,导致滇中早寒武世梅树村组沉积期古海洋环境由浅水氧化向深水还原逐渐过渡,而昆阳磷矿形成于该阶段海进旋回沉积早期。 展开更多
关键词 RE-OS同位素 黑色页岩 磷块岩 海侵 梅树村组
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SpaceOS中若干全局性质的形式化描述和验证 被引量:7
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作者 顾海博 付明 +1 位作者 乔磊 冯新宇 《小型微型计算机系统》 CSCD 北大核心 2019年第1期141-148,共8页
SpaceOS是北京控制工程研究所自主研发的嵌入式实时操作系统,已被应用于探月工程、空间站等重大航天项目.SpaceOS作为底层系统软件,是影响航天任务成败的关键因素. SpaceOS在设计中提出了一些多个内核模块(如任务管理、调度、通信和时... SpaceOS是北京控制工程研究所自主研发的嵌入式实时操作系统,已被应用于探月工程、空间站等重大航天项目.SpaceOS作为底层系统软件,是影响航天任务成败的关键因素. SpaceOS在设计中提出了一些多个内核模块(如任务管理、调度、通信和时间管理等)相互协同过程中所需要满足的全局性质.本文扩展已有的操作系统验证框架支持全局性质的推理,为SpaceOS内核建立抽象模型,给出主要系统调用的抽象规范,并基于设计需求给出形式化定义描述若干全局性质,通过严格的数学证明保证SpaceOS在抽象设计层面上满足这些全局性质.所有工作都在证明助手Coq中完成. 展开更多
关键词 SpaceOS 形式化验证 全局性质 操作系统内核 COQ
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Outcome and prognostic factors in 110 consecutive patients with primary uterine leiomyosarcoma:A Rare Cancer Network study 被引量:2
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作者 Alessandra Franzetti Pellanda Berardino De Bari +19 位作者 Elisabeth Deniaud-Alexandre MarcoKrengli Paul Van Houtte Antonella Riehetti Salvador Villa Hadassah Goldberg EwaSzutowiez-Zielifiska Michel Bolla Heidi Rutten Marc Van Eijkeren Philip Poortmans Guido Henke Yavuz Anaeak Steve Chan Christine Landmann Carine Kirkove LueianoScandolaro Jacques Bernier Rene-Olivier Mirimanof Mahmut Ozsahin 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2017年第6期521-532,共12页
Objective: Primary uterine leiomyosarcomas (ULMS) are rare, and the optimal treatment is controversial. We aimed to assess the outcome and prognostic factors in a multicenter population of women treated for primary... Objective: Primary uterine leiomyosarcomas (ULMS) are rare, and the optimal treatment is controversial. We aimed to assess the outcome and prognostic factors in a multicenter population of women treated for primary ULMS. Methods: We retrospectively collected data of 110 women treated in 19 institutions of the Rare Cancer Network (RCN). Inclusion criteria consisted of a pathology report confirming the diagnosis of ULMS, aged 18-80 years, complete International Federation of Gynecology and Obstetrics (FIGO) stage information, complete information on treatment, and a minimum follow-up of 6 months. Local control (LC) and locoregional control (LRC), overall survival (OS) and disease-free survival (DFS) rates were computed using the Kaplan-Meier method. Univariate analysis was implemented using the log rank test, and multivariate analysis using the Cox model. Results: All patients underwent surgery. Seventy-five patients (68%) received adjuvant radiotherapy (RT), including brachytherapy in 18 (I 6%). Seventeen patients (15 %) received adjuvant chemotherapy. Median follow-up was 58 (range, 6-240) months. Five-year OS and DFS rates were 50% and 34%, and LC and LRC rates were 88% and 72%, respectively. On multivariate analysis, independent favorable prognostic factors were younger age, FIGO stage I, small tumor size, previous uterine disease, and no vascular invasion for OS and DFS. FIGO stage was the only favorable factor influencing LRC. Adjuvant local or systemic treatments did not improve the outcomes. Eight patients treated with RT presented a grade 3 acute toxicity, and only one patient with grade 3 late toxicity. Conclusions: In this large population of primary ULMS patients, we found good results in terms of LC and LRC. Nevertheless, OS remains poor, mainly due to the occurrence of distant metastases. An early diagnosis seemed to improve the prognosis of the patients. Adjuvant local or systemic treatments, or more aggressive surgical procedures such as the Wertheim procedure, did not seem to impact the outcome. 展开更多
关键词 Uterine leiomyosarcoma prognostic factors RADIOTHERAPY overall survival local control
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Understanding the importance of autophagy in human diseases using Drosophila 被引量:5
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作者 Arindam Bhattacharjee áron Szabó +2 位作者 Tamás Csizmadia Hajnalka Laczkó-Dobos Gábor Juhász 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2019年第4期157-169,共13页
Autophagy is a lysosome-dependent intracellular degradation pathway that has been implicated in the pathogenesis of various human diseases, either positively or negatively impacting disease outcomes depending on the s... Autophagy is a lysosome-dependent intracellular degradation pathway that has been implicated in the pathogenesis of various human diseases, either positively or negatively impacting disease outcomes depending on the specific context. The majority of medical conditions including cancer, neurodegenerative diseases, infections and immune system disorders and inflammatory bowel disease could probably benefit from therapeutic modulation of the autophagy machinery. Drosophila represents an excellent model animal to study disease mechanisms thanks to its sophisticated genetic toolkit, and the conservation of human disease genes and autophagic processes. Here, we provide an overview of the various autophagy pathways observed both in flies and human cells(macroautophagy, microautophagy and chaperone-mediated autophagy), and discuss Drosophila models of the above-mentioned diseases where fly research has already helped to understand how defects in autophagy genes and pathways contribute to the relevant pathomechanisms. 展开更多
关键词 DROSOPHILA Neurodegeneration Alzheimer’s DISEASE Parkinson’s DISEASE Cancer Inflammatory BOWEL DISEASE AUTOPHAGY
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Validation of a SPME-GC Method for Azoxystrobin and Pyraclostrobin in Blueberries, and Their Degradation Kinetics 被引量:11
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作者 Martín S. Munitz Silvia L. Resnik +1 位作者 María I. T. Montti Silvia Visciglio 《Agricultural Sciences》 2014年第11期964-974,共11页
Analytical method for the residues of strobilurins azoxystrobin and pyraclostrobin in blueberries was developed. Fungicide residues were determined by solid-phase microextraction (SPME) cou-pled to gas chromatography ... Analytical method for the residues of strobilurins azoxystrobin and pyraclostrobin in blueberries was developed. Fungicide residues were determined by solid-phase microextraction (SPME) cou-pled to gas chromatography with micro-electron capture detector. The effect of pH values and fiber coatings were studied. The SPME fiber coating selected was 100 μm PDMS. The method is selective with adequate precision and high accuracy and sensitivity. Recoveries ranged within the 100% - 106% range for azoxystrobin, and 96% - 106% range for pyraclostrobin;and detection and quantification limits were 2.0 and 6.0 μg/kg for azoxystrobin, and 26.0 and 86.0 μg/kg for py-raclostrobin, respectively. Statistical parameters indicated the occurrence of matrix effect;con-sequently calibration was performed on spiked samples. Degradation of azoxystrobin and pyra-clostrobin was studied in blueberry fields located in Concordia, Argentina, with fruits from Emerald and Jewel varieties. The degradation of these fungicides in both blueberry varieties studied followed a first order rate kinetics, and the half-life for azoxystrobin was 11.6 and 17.8 days for Emerald and Jewel cultivars;and for pyraclostrobin was 5.5 and 8.0 days, respectively. 展开更多
关键词 BLUEBERRIES AZOXYSTROBIN PYRACLOSTROBIN DEGRADATION KINETICS SPME/GC
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Low-temperature plasma enhanced atomic layer deposition of large area HfS2 nanocrystal thin films
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作者 Ailing Chang Yichen Mao +5 位作者 Zhiwei Huang Haiyang Hong Jianfang Xu Wei Huang Songyan Chen Cheng Li 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第3期427-432,共6页
Hafnium disulfide(HfS2) is a promising two-dimensional material for scaling electronic devices due to its higher carrier mobility, in which the combination of two-dimensional materials with traditional semiconductors ... Hafnium disulfide(HfS2) is a promising two-dimensional material for scaling electronic devices due to its higher carrier mobility, in which the combination of two-dimensional materials with traditional semiconductors in the framework of CMOS-compatible technology is necessary. We reported on the deposition of HfS2 nanocrystals by remote plasma enhanced atomic layer deposition at low temperature using Hf(N(CH3)(C2H5))4 and H2S as the reaction precursors. Selflimiting reaction behavior was observed at the deposition temperatures ranging from 150℃ to 350℃, and the film thickness increased linearly with the growth cycles. The uniform HfS2 nanocrystal thin films were obtained with the size of nanocrystal grain up to 27 nm. It was demonstrated that higher deposition temperature could enlarge the grain size and improve the HfS2 crystallinity, while causing crystallization of the mixed HfO2 above 450℃. These results suggested that atomic layer deposition is a low-temperature route to synthesize high quality HfS2 nanocrystals for electronic device or electrochemical applications. 展开更多
关键词 HfS2 ATOMIC LAYER DEPOSITION surface MORPHOLOGY
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The first pterosaur 3-D egg:Implications for Pterodaustro guinazui nesting strategies,an Albian filter feeder pterosaur from central Argentina 被引量:2
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作者 Gerald Grellet-Tinner Michael B.Thompson +3 位作者 Lucas E.Fiorelli Eloísa Argaaraz Laura Codorniú E.Martín Hechenleitner 《Geoscience Frontiers》 SCIE CAS CSCD 2014年第6期759-765,共7页
The increasing number of fossil pterosaur eggs sheds light on nesting environments and breeding be- haviors of these extinct flying reptiles. Here we report the first partial three-dimensional egg of the pterosaur, Pt... The increasing number of fossil pterosaur eggs sheds light on nesting environments and breeding be- haviors of these extinct flying reptiles. Here we report the first partial three-dimensional egg of the pterosaur, Pteroduustro guinazui, from central Argentina. The specimen was discovered from the same Albian deposits as the exceptional R guinazui embryo described in 2004. Microscopic characterizations indicate a pristine preservation of the 50 Bm thick calcium carbonate, which differs significantly from the soft shell of Chinese pterosaur eggs. Estimate of the eggshell conductance implies that the nest had a minimum moisture content of 75%. This moisture estimate, combined with geological and taphonomical data, suggests that P. guinazui may have adopted a nesting strategy similar to those of grebes and flamingos rather than being buried on land, as previously hypothesized. Moreover, our results demon- strate that the nesting paleoenvironment of this pterosaur species was closely linked to a mesohaline lacustrine ecosystem in a basin governed by regional tectonic subsidence, a setting characteristic for the feeding and reproduction of modern flamingos. 展开更多
关键词 Pterosaur fossil eggsPterosaur eggshellPterodaustro guinazuiGondwanaEggshell conductance
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Clinical implications of diabetes in chronic liver disease:Diagnosis,outcomes and management,current and future perspectives 被引量:9
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作者 Diego García-Compeán Emanuela Orsi +6 位作者 Ramesh Kumar Felix Gundling Tsutomu Nishida Jesús Zacarías Villarreal-Pérez Ángel N Del Cueto-Aguilera JoséA González-González Giuseppe Pugliese 《World Journal of Gastroenterology》 SCIE CAS 2022年第8期775-793,共19页
Diabetes mellitus(DM)is common in liver cirrhosis(LC).The pathophysiological association is bidirectional.DM is a risk factor of LC and LC is a diabetogenic condition.In the recent years,research on different aspects ... Diabetes mellitus(DM)is common in liver cirrhosis(LC).The pathophysiological association is bidirectional.DM is a risk factor of LC and LC is a diabetogenic condition.In the recent years,research on different aspects of the association DM and LC has been intensified.Nevertheless,it has been insufficient and still exist many gaps.The aims of this review are:(1)To discuss the latest understandings of the association of DM and LC in order to identify the strategies of early diagnosis;(2)To evaluate the impact of DM on outcomes of LC patients;and(3)To select the most adequate management benefiting the two conditions.Literature searches were conducted using Pub Med,Ovid and Scopus engines for DM and LC,diagnosis,outcomes and management.The authors also provided insight from their own published experience.Based on the published studies,two types of DM associated with LC have emerged:Type 2 DM(T2 DM)and hepatogenous diabetes(HD).High-quality evidences have determined that T2 DM or HD significantly increase complications and death pre and post-liver transplantation.HD has been poorly studied and has not been recognized as a complication of LC.The management of DM in LC patients continues to be difficult and should be based on drug pharmacokinetics and the degree of liver failure.In conclusion,the clinical impact of DM in outcomes of LC patients has been the most studied item recently.Nevertheless many gaps still exist particularly in the management.These most important gaps were highlighted in order to propose future lines for research. 展开更多
关键词 Diabetes mellitus Liver cirrhosis Hepatogenous diabetes Clinical implications THERAPY
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毛乌素沙地沙丘活化过程中油蒿(Artemisia ordosica)根系特征 被引量:8
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作者 岳艳鹏 孙迎涛 +6 位作者 庞营军 成龙 周虹 贾晓红 赵雨兴 赵河聚 吴波 《中国沙漠》 CSCD 北大核心 2020年第3期177-184,共8页
根系是植物的重要营养器官,轻微的环境变化也会引起根系的变化。采用时空代替法,在毛乌素沙地选取固定沙丘、轻度活化沙丘、中度活化沙丘、重度活化沙丘上的油蒿(Artemisia ordosica)植株,采用全根分层挖掘的方法调查根系生态特征。结... 根系是植物的重要营养器官,轻微的环境变化也会引起根系的变化。采用时空代替法,在毛乌素沙地选取固定沙丘、轻度活化沙丘、中度活化沙丘、重度活化沙丘上的油蒿(Artemisia ordosica)植株,采用全根分层挖掘的方法调查根系生态特征。结果表明:油蒿表现出深根性轴根植物的特点,不同活化程度沙丘油蒿根系生物量均以粗根最大\,中粗根次之\,细根最小,但沙丘的活化显著弱化了油蒿的轴根特征;在沙丘活化的初期(固定沙丘、轻度活化沙丘)油蒿根系垂直方向分布较深(平均>200 cm),水平方向分布范围较小,侧根数量较多,随着沙丘活化程度的增加,油蒿根系分布浅层化,侧根数量减少但水平方向分布范围增加,根幅增大,油蒿有向须根植物演变的趋势;从固定沙丘到重度活化沙丘,由于植被盖度的降低,风沙活动的加剧,沙埋的发生导致油蒿地下总生物量不断增加,根冠比也呈增加趋势。生境的改变,导致油蒿根系的分配格局发生改变,最终适应沙丘活化后的土壤水分条件以及相应的生态环境的改变。 展开更多
关键词 生物量 根系分布 根冠比
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