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Extensions of Certain Modules Over the First Weyl Algebra

Science China Mathematics 1994年第5期37卷 535-546页

作者：肖杰 freddy van Oystaeyen Department of Mathematics Beijing Normal UniversityBeijing 100875PRC Department of Mathematics University of Antwerp UIA Antwerpen B-2610 Belgium

Using a method stemming from the representation theory of finite-dimensional algebra’s,results about a category of Artinian modules over the first Weyl algebra consisting of objects having composition series with composition factors isomorphic to prescribed ones have been *** category corresponds to a tube of z/2z type and it is serial and *** Auslander-Reiten formula in this category describing the functor Ext,,(-,-) in terms of the AR-quiver has been *** dimensions of Ext4(M,N) for M and N in different tubes are calculated.

关键词： Weyl algebra Artinian module tube

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Understanding and tuning blue-to-near-infrared photon cutting by the Tm^(3+)/Yb^(3+) couple

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Light(Science & Applications) 2020年第1期9卷 992-1000页

作者： Dechao Yu Ting Yu Arnoldus Jvan Bunningen Qinyuan zhang Andries Meijerink freddy T.Rabouw Debye Institute for Nanomaterials Science Utrecht UniversityPrincetonplein 13584 CC UtrechtThe Netherlands State Key Laboratory of Luminescence Materials and Devices Institute of Optical Communication MaterialsSouth China University of TechnologyGuangzhou 510641China

Lanthanide-based photon-cutting phosphors absorb high-energy photons and‘cut’them into multiple smaller excitation *** quanta are subsequently emitted,resulting in photon-conversion efficiencies exceeding *** photon-cutting process relies on energy transfer between optically active lanthanide ions doped in the ***,it is not always easy to determine,let alone predict,which energy-transfer mechanisms are operative in a particular *** makes the identification and design of new promising photon-cutting phosphors *** we unravel the possibility of using the Tm^(3+)/Yb^(3+) lanthanide couple for photon *** compare the performance of this couple in four different host *** energy transfer from Tm^(3+)to Yb^(3+) would enable blue-to-near-infrared conversion with 200% ***,we identify phonon-assisted cross-relaxation as the dominant Tm^(3+)-to-Yb^(3+) energy-transfer mechanism in YBO_(3),YAG,and Y_(2)O_(3).In NaYF_(4),in contrast,the low maximum phonon energy renders phonon-assisted cross-relaxation impossible,making the desired cooperative mechanism the dominant energy-transfer *** work demonstrates that previous claims of high photon-cutting efficiencies obtained with the Tm^(3+)/Yb^(3+) couple must be interpreted with ***,the Tm^(3+)/Yb^(3+) couple is potentially promising,but the host material-more specifically,its maximum phonon energy-has a critical effect on the energy-transfer mechanisms and thereby on the photon-cutting performance.

关键词： couple phonon lanthanide

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高分辨电感耦合等离子体质谱法测定大气气溶胶中铅同位素比值

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质谱学报 2004年第B10期25卷 179-180页

作者：李冰刘成德董树屏 VeerleVanLierde FrankVanhaecke freddy.C.Adams 国家地质实验测试中心，北京100037 中国环境科学研究院，北京100012 国家环境分析测试中心，北京100029 LaboratoryofAnalyticalChemistry GhentUniversityInstituteforNuclearSciencesProeftuinstraat86B-9000GhentBelgium UniversityofAntwerp UIAB-2610Wilrijk-AntwerpenBelgium

采用高分辨电感耦合等离子体质谱技术(HR—ICP—MS)分析了48个不同季节大气气溶胶颗粒样品中铅同位素比值，为中国城市铅污染源研究提供数据。样品采至中国北京和长岛地区(2002年～2003年期间)。^205Pb／^207Pb和^208Pb／^207Pb的10次... 详细信息

采用高分辨电感耦合等离子体质谱技术(HR—ICP—MS)分析了48个不同季节大气气溶胶颗粒样品中铅同位素比值，为中国城市铅污染源研究提供数据。样品采至中国北京和长岛地区(2002年～2003年期间)。^205Pb／^207Pb和^208Pb／^207Pb的10次测定标准偏差为0．05％～0．19％。

关键词：高分辨电感耦合等离子体质谱大气气溶胶铅同位素比值污染源

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Prognostic Signification of Admission Hyperglycemia among Acute Stroke Patients in Intensive Care Units in Kinshasa,the Democratic Republic of the Congo

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World Journal of Cardiovascular Diseases 2019年第9期9卷 665-680页

作者： Josée K.Tshituta Francois B.Lepira Francois P.Kajingulu Jean Robert R.Makulo Ernest K.Sumaili Pierre z.Akilimali Aliocha N.Nkodila freddy M.Mbuyi Angele I.Masewu Stephane Mutombo Eric B.Amisi Jean Pierre M.Ilunga Wilfrid B.Mbombo Patrick M.Mukuna Adolphe M.Kilembe Department of Anesthesiology and Reanimation University of Kinshasa HospitalKinshasaThe Democratic Republic of the Congo Division of Nephrology Department of Internal MedicineUniversity of Kinshasa HospitalKinshasaThe Democratic Republic of the Congo Department of Epidemiology&Biostatistics Kinshasa School of Public HealthUniversity of Kinshasa School of MedicineKinshasaThe Democratic Republic of the Congo Centre medical cite des Aveugles KinshasaThe Democratic Republic of the Congo

BACKGROUND AND AIM: Although admission hyperglycemia has been reported to be associated with unfavorable outcomes in acute stroke, little is known about this association in sub-Saharan Africa. Therefore, the aim of the present study was to assess the prognostic significance of admission hyperglycemia in the acute phase of stroke in Congolese patients. METHODS: In a multicenter prospective cohort study, consecutive patients with acute stroke were examined in 5 Emergency Rooms or Intensive Care Units of Kinshasa between July 15th, 2017 and March 15th, 2018. The severity of stroke was assessed at admission using the Glasgow Coma Scale. Stress hyperglycemia was defined as random blood glucose levels at admission > 140 mg/dL in patients without known type 2 diabetes mellitus (T2DM). The endpoint was 10-day all-cause in-hospital mortality. Survival (time-to-death) curves were built using the Kaplan Meier methods. Cox proportional analysis was used to identify predictors of 10-day all-cause in-hospital mortality. The predictive performance of blood glucose level to predict 10-day all-cause in-hospital mortality was assessed using ROC curve analysis. RESULTS: Out of 194 patients (mean age 58.7 ± 13.1 years;64% males, 74.7% light to moderate stroke severity;63.4% ischemic stroke) enrolled, 106 (54.6%) had admission hyperglycemia with 77 (72.6%) having stress hyperglycemia. Ninety four deaths (48.5%);mortality rate of 6 deaths per 100 person-days (95%CI 2.7 - 9.3) occurred during a median follow up time 6 (5 - 7) days equivalent to 1542 person-days. Independent predictors of 10-day all-cause in-hospital mortality were admission hyperglycemia regardless of diabetes status (aHR 3.77;95%CI 1.92 - 7.42;p < 0.001), GCS - 5.23;p = 0.001) and non-use of mechanical ventilation (aHR 1.97;95%CI 1.05 - 3.70;p = 0.034). Blood glucose concentrations (AUC 0.743;95%CI 0.672 - 0.814) had a better predictive performance for 10-day all-cause in-hospital mortality with an optimal value of 154 m

关键词： Admission Hyperglycemia Stroke Prognostic Significance Black Africans

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