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Littérature scientifique sur le sujet « Top ma »

Auteur : Grafiati

Publié le 9 mars 2023

Mis à jour le 10 mars 2023

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Articles de revues sur le sujet "Top ma"

Barreau, Jean-Jacques. « Si ma constitution le supporte ». Topique 103, n^o 2 (2008) : 13. http://dx.doi.org/10.3917/top.103.0013.

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Haugen, Kjetil K. « Who are the real top scorers : Algorithmically resorting a top scorer list by a limited set of preference assumptions ». Mathematics for Application 9, n^o 1 (28 juin 2020) : 17–30. http://dx.doi.org/10.13164/ma.2020.02.

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Veit, Camille. « « Ma petite entreprise ne connaît pas la crise » ». Topique 148, n^o 1 (2020) : 103. http://dx.doi.org/10.3917/top.148.0103.

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Mintarningsih, H. Y. « SPIRIT “MA TOP MA FIT” DALAM MENGEMBANGKAN LEMBAGA KURSUS DAN PELATIHAN OTOMOTIF RODA DUA ». JIV 13, n^o 1 (28 juin 2018) : 67–73. http://dx.doi.org/10.21009/jiv.1301.8.

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North Central Timor District has two courses and training institutions run by the community. This amount has not changed from since 2007. Whereas according to Central Bureau of Statistics of East Nusa Tenggara, North Central Timor District Regency until 2015 has 22,450 units of motorcycles. That means North Central Timor District requires more than two courses and training institutions to overcome the problem of motor. In addition, from the observation, the existing condition of courses and training institutions also does not qualify as an educational institution. Though the district is famous for the spirit of “Togetherness” which put together, in the same lightweight principle carried, the same weight be borne in various activities. However in reality, the business activities of the community die. What exactly is the designation of “Togetherness” spirit in North Central District of Timor? To answer that question, in May 2017 was conducted research using an open questionnaire data-collection tool. Questionnaires were distributed to 25 respondents. From the results of the analysis of respondents’ answers found the answer that, open a new business, only a priority to six after the needs of marriage, education, garden cleaning, harvest, and death. The reason, opening a business can take advantage of government facilities. In addition, opening new business direct profits is limited to certain people only. Results not necessarily can be enjoyed together. Moreover, the priority tendency above it is an important priority. Although not all of them, for the community. Despite some objections to the issue, in fact, opening a new business is not a priority to the “Ma Top Ma Fit” spirit, in the district of North Central Timor.

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Hohenegger, Johann, Stjepan Ćorić et Michael Wagreich. « Timing of the Middle Miocene Badenian Stage of the Central Paratethys ». Geologica Carpathica 65, n^o 1 (1 février 2014) : 55–66. http://dx.doi.org/10.2478/geoca-2014-0004.

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Abstract A new and precisely defined chronometric subdivision of the Badenian (Middle Miocene, regional stage of Central Paratethys) is proposed. This uses global events, mainly geomagnetic polarity reversals as correlated chronometric boundaries, supported by climatic and sea-level changes in addition to isotope events and biostratigraphic data. The Karpatian/ Badenian boundary lies at 16.303 Ma, at the top of Chron C5Cn.2n, which is near the base of the Praeorbulina sicana Lowest-occurrence Zone (LOZ). The Badenian/Sarmatian boundary is placed at the top of polarity Chron C5Ar.2n, thus at 12.829 Ma. In relation to three sea level cycles TB 2.3, TB 2.4 and TB 2.5 and astronomically confirmed data, the Badenian can be divided into three parts of nearly equivalent duration. The Early Badenian as newly defined here ranges from 16.303 to 15.032 Ma (top of polarity Chron C5Bn.2n). The younger boundary correlates roughly to the base of the planktonic foraminifera Orbulina suturalis LOZ at 15.10 Ma, the HO (Highest Occurrence) of the nannofossil Helicosphaera ampliaperta at 14.91 Ma (NN4/NN5 boundary) and the Lan2/Ser1 sequence boundary at 14.80 Ma. The subsequent Mid Badenian ranges from 15.032 Ma to 13.82 Ma; the latter datum correlates with the base of the Serravallian, characterized by a strong global cooling event reflected in the oxygen isotope event Mi3b. The main part of cycle TB 2.4 falls into the Mid Badenian, which can be subdivided by a short cooling event at 14.24 Ma during the Middle Miocene Climate Transition (14.70 to 13.82 Ma). The HCO (Highest common occurrence) of the nannofossil Helicosphaera waltrans at 14.357 Ma supports this division, also seen in the tropical plankton Zones M6 Orbulina suturalis LOZ and M7 Fohsella peripheroacuta LOZ that correspond roughly to the lower and upper Lagenidae zones in the Vienna Basin, respectively. The Late Badenian is delimited in time at the base to 13.82 Ma by the Langhian/Serravallian boundary and at the top by the top of polarity Chron C5Ar.2n at 12.829 Ma. The Mediterranean Langhian/Serravallian boundary can be equated with the Mid/Late Badenian boundary at 13.82 Ma. However, the Karpatian/Badenian boundary at 16.303 Ma, a significant event easily recognizable in biostratigraphy, paleoclimate evolution and sequence stratigraphy, cannot be equated with the proposed global Burdigalian/Langhian, and thus Early/Middle Miocene boundary, at 15.974 Ma

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Baadsgaard, H., J. F. Lerbekmo, J. R. Wijbrans, C. C. Swisher III et M. Fanning. « Multimethod radiometric age for a bentonite near the top of the Baculites reesidei Zone of southwestern Saskatchewan (Campanian–Maastrichtian stage boundary?) ». Canadian Journal of Earth Sciences 30, n^o 4 (1 avril 1993) : 769–75. http://dx.doi.org/10.1139/e93-063.

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A 15 cm thick bentonite at the top of the Baculites reesidei Zone in Cruikshank Coulee north of Herbert in southwestern Saskatchewan yielded biotite, sanidine, plagioclase, and zircon. Rb–Sr analyses give a mineral isochron with an age of 72.5 ± 0.2 Ma (± 2σ). U–Pb analyses of zircon produced concordant 206Pb/238U and 207Pb/235U ages of 72.4 ± 0.4 Ma (± 2σ) and 72.6 ± 0.4 Ma (± 2σ), respectively. Laser 40Ar/39Ar dating of sanidine and biotite revealed ages of 72.5 ± 0.2 Ma (± SE) and 72.6 ± 0.2 Ma (± SE), respectively. If the Campanian–Maastrichtian stage boundary is near the top of the Baculites reesidei Zone, then the overall average age of 72.5 ± 0.4 Ma dates the stage boundary.

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Bumby, Adam, Geoffrey H. Grantham et Neo Geogracious Moabi. « The structural evolution of the Straumsnutane and western Sverdrupfjella areas, western Dronning Maud Land, Antarctica : implications for the amalgamation of Gondwana ». Geological Magazine 157, n^o 9 (10 février 2020) : 1428–50. http://dx.doi.org/10.1017/s0016756819001523.

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AbstractThe study area is located across the Kalahari Craton – Maud Belt boundary in Dronning Maud Land (DML), Antarctica. The ∼1100 Ma Maud Belt in the east is situated where the ∼900–600 Ma East African and ∼530–500 Ma Kuunga orogenies overlap. The Kalahari Craton cover in the west of the study area comprises ∼1100 Ma Straumsnutane Formation lavas in Straumsnutane. In Straumsnutane, early ∼1100 Ma low-grade structures suggest top-to-the-NW deformation. Younger ∼525 Ma structures suggest conjugate top-to-ESE and -WNW transport under low-grade conditions. Western Straumsnutane and Ahlmannryggen do not show the same complex deformation, the intense deformation being restricted to NE Straumsnutane along the eastern margin of the Kalahari Craton. In Sverdrupfjella, in the east, the Maud Belt is underlain by medium-grade, deformed ∼1140 Ma supracrustal gneisses and younger intrusions. Four deformation phases in the gneisses comprise D1 + D2 with top-to-the-N and -NW folds, D3 top-to-the-S and -SE folding and D4 brittle faulting. Syn-D3 emplacement of granitoid veins is inferred at ∼490 Ma. Comparison of the deformation vergence of NE Straumsnutane with western Sverdrupfjella suggests D1 in Straumsnutane is correlatable with D1 + D2 Mesoproterozoic structures in western Sverdrupfjella. D2 deformation in Straumsnutane can be correlated with D3 structures and Cambrian-age granites in Sverdrupfjella. D2 deformation in eastern Straumsnutane and D3 in western Sverdrupfjella are inferred to have occurred in a mega-nappe footwall, implying the Ritscherflya Supergroup cratonic cover in eastern Straumsnutane was partially submerged in the footwall, the mega-nappe formed during Gondwana amalgamation, involving collision between N and S Gondwana in the Kuunga Orogeny, ∼530–500 Ma ago.

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Leitch, Craig H. B., C. T. Hood, Xiao-Lin Cheng et A. J. Sinclair. « Tip Top Hill volcanics : Late Cretaceous Kasalka Group rocks hosting Eocene epithermal base- and precious-metal veins at Owen Lake, west-central British Columbia ». Canadian Journal of Earth Sciences 29, n^o 5 (1 mai 1992) : 854–64. http://dx.doi.org/10.1139/e92-073.

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Rocks hosting the Silver Queen epithermal Au–Ag–Zn–Pb–Cu vein deposit near Owen Lake, British Columbia, belong to the Tip Top Hill volcanics. They are lithologically similar to the informally named Upper Cretaceous Kasalka Group rocks exposed in the type area at Tahtsa Lake, 75 km southwest of the deposit, and at Mount Cronin, 100 km northwest of the deposit. The Kasalka Group rocks in the Tahtsa Lake area give questionable dates of 105 ± 5 Ma by K–Ar on whole rock but are cut by intrusions dated at 83.8 ± 2.8 Ma by K–Ar on biotite. The sequence at the Silver Queen deposit includes a polymictic conglomerate, followed upward by felsic fragmental rocks and a thick porphyritic andesite flow and sill unit, cut by microdiorite and quartz–feldspar porphyry intrusions. The porphyritic andesite and the microdiorite have been dated as Late Cretaceous (78.3 ± 2.7 and 78.7 ± 2.7 Ma, respectively, by K–Ar on whole rock), close to previous dates for these rocks (77.1 ± 2.7 and 75.3 ± 2.0 Ma, respectively). The quartz–feldspar porphyry intrudes the porphyritic andesites but has an older U–Pb zircon date of 84.6 ± 0.2 Ma, probably due to underestimation of the true age of the host rocks by the K–Ar whole-rock method. Later dykes correlate with younger volcanic rocks belonging to the Ootsa Lake and Endako groups. Eocene pre- and postmineral plagioclase-rich dykes (51.9 ± 1.8 to 51.3 ± 1.8 Ma) and late diabase dykes (50.4 ± 1.8 Ma; all by K–Ar on whole rock) may be correlative with trachyandesite volcanics of the Goosly Lake Formation, part of the Eocene Endako Group. These volcanics have been dated elsewhere at 55.6 ± 2.5 to 48.8 ± 1.8 Ma by K–Ar on whole rock and biotite, respectively. Mineralization at Silver Queen is therefore similar in age to, but slightly younger than, the producing Equity mine located 30 km to the northeast, which is estimated at 58.5 ± 2.0 Ma by K–Ar on whole rock.

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Drossart, Francis. « « Ce meurtre est tout ce qui me reste de ma vertu. » (Lorenzaccio) ». Topique 138, n^o 1 (2017) : 81. http://dx.doi.org/10.3917/top.138.0081.

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Degaspari, John. « Look, Ma, No Pilot ! » Mechanical Engineering 125, n^o 11 (1 novembre 2003) : 42–44. http://dx.doi.org/10.1115/1.2003-nov-3.

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This paper reviews history of unmanned aircraft that are making news today. A team led by the inventor Charles Kettering had developed the airborne contraption, conceived as a top-secret weapon to deliver explosives against enemy troops. The craft was the first practical unmanned airplane. Unmanned aerial vehicles such as this circa 1946 target drone were built by the Radioplane Co. to train antiaircraft gunners during World War II. Weary bombers, such as the radio-controlled B-17G Flying Fortress, were used with small success as flying bombs during the World War II. World War II era target drones preceding unmanned aerial vehicles for surveillance in the coming decades. In 1999, Northrop Grumman boosted its presence in target aircraft further by acquiring Ryan Aeronautical, the company that built the Spirit of St. Louis for Charles Lindbergh in 1927.

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Thèses sur le sujet "Top ma"

FERRARIO, RAVASIO SILVIA. « Top-mass observables : all-orders behaviour, renormalons and NLO + Parton Shower effects ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241087.

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In questa tesi ci concentriamo su alcuni aspetti teorici che concernono la determinazione della massa del quark top ($ m_t $), problema che persiste nell'essere altamente controverso. Generalmente, per misurare la massa del top, sono necessarie predizioni teoriche dipendenti da $m_t$. Il parametro $m_t$ coincide con la massa fisica, che è collegata alla massa nuda attraverso una procedura di rinormalizzazione. Sono possibili diversi schemi di rinormalizzazione per la massa e il più naturale sembra essere quello della massa polo. Tuttavia, nel caso di oggetti colorati, la massa polo contiene rinormaloni di origine infrarossa, i quali si manifestano come coefficienti che crescono fattorialmente, rovinando la convergenza delle serie perturbativa e portando ad ambigutá di ordine $\Lambda_{\rm QCD}$. D’altro canto, shemi di massa come l’$\overline{\rm MS}$ sono liberi da questi rinormaloni. Fortunatamente, l’ambiguitá rinormalonica sembra essere ben al di sotto dell’errore sistematico quotato per le misurazioni della massa polo. Pertanto questo tipo di determinazione è ancora affidabile. Nella prima parte della tesi studiamo la presenza di rinormaloni in osservabili che possono essere impiegate per la determinazione della massa del top. Consideriamo un modello semplificato per descrivere il processo $W^* \to t \bar{b} \to W b \bar{b}$. Il calcolo è eseguito nel limite in cui il numero di sapori dei quark leggeri $n_f$ è molto grande, utilizzando un nuovo metodo con cui è possibile valutare numericamente una generica osservabile all’ordine $\alpha_s(\alpha_s n_f)^n$ per ogni valore di $n$. Due sono le sorgenti di rinormaloni nelle nostre osservabile: l’uso della massa polo e la richiesta di tagli cinematici sui momenti dei jet. Per questo, predizioni ottenute nello schema polo sono comparate con quelle calcolate nello schema $\overline{\rm MS}$. Dalla nostra analisi risulta che la sezione d’urto senza tagli, se espressa in termini della massa $\overline{\rm MS}$, è libera da rinormaloni lineari, i quali appaiono però in ogni schema appena vengono introdotti dei tagli cinematici relativi al momento dei jet. Inoltre, la massa dei prodotti di decadimento del top è sempre affetta da rinormaloni lineari. L’energia del bosone $W$ ha un rinormalone in ogni schema nel limite in cui la larghezza di decadimento del top è zero, altrimenti, quando una larghezza finita è usata nel calcolo, tali rinormaloni sono assenti nello schema $\overline{\rm MS}$. Le determinazioni più precise della massa del top sono quelle dirette, ossia quelle basate sulla ricostruzione della cinematica dei prodotti di decadimento del top. Queste misure sono basate sull’uso di generatori di eventi Monte Carlo. I generatori che vengono utilizzati devono essere il più accurati possibili, onde evitare imprecisioni nella misura. A questo proposito, nella seconda parte della tesi confrontiamo diversi generatori NLO, implementati nel codice {\tt POWHEG BOX}, che differiscono per il livello di accuratezza impiegato nel descrivere il decadimento del top. Anche l’impatto dei programmi Monte Carlo che implementano la “parton shower”, e che quindi completano gli eventi generati da POWHEG BOX, è oggetto di studio in questa seconda parte della tesi. In particolare, noi ci focalizziamo sui programmi più usati, Pythia8.2 ed Herwig7.1, e presentiamo un metodo per interfacciarli a processi contenenti risonanze che possono emettere radiazione. Il paragone fra diversi generatori Monte Carlo che hanno formalmente lo stesso livello di accuratezza è infatti un passo obbligato verso una stima ragionevole dell’incertezza associata alla misurazione della massa del quark top.
In this thesis we focus on the theoretical subtleties of the top-quark mass ($m_t$) determination, issue which persists in being highly controversial. Typically, in order to infer the top mass, theoretical predictions dependent on $m_t$ are employed. The parameter $m_t$ is the physical mass, that is connected with the bare mass though a renormalization procedure. Several renormalization schemes are possible and the most natural seems to be the pole-mass one. However, the pole mass is not very well defined for a coloured object like the top quark. The pole mass is indeed affected by the presence of infrared renormalons. They manifest as factorially growing coefficients that spoil the convergence of the perturbative series, leading to ambiguities of order of $\Lambda_{\rm QCD}$. On the other hand, short-distance mass schemes, like the $\overline{\rm MS}$, are known to be free from such renormalons. Luckily, the renormalon ambiguity seems to be safely below the quoted systematic errors on the pole-mass determinations, so these measurements are still valuable. In the first part of the thesis, we investigate the presence of linear renormalons in observables that can be employed to determine the top mass. We considered a simplified toy model to describe $W^* \to t \bar{b} \to Wb \bar{b}$. The computation is carried out in the limit of a large number of flavours ($n_f$), using a new method that allows to easily evaluate any infrared safe observable at order $\alpha_s(\alpha_s n_f)^n$ for any $n$. The observables we consider are, in general, affected by two sources of renormalons: the pole-mass definition and the jet requirements. We compare and discuss the predictions obtained in the usual pole scheme with those computed in the $\overline{\rm MS}$ one. We find that the total cross section without cuts, when expressed in terms of the $\overline{\rm MS}$ mass, does not exhibit linear renormalons, but, as soon as selection cuts are introduced, jets-related linear renormalons arise in any mass scheme. In addition, we show that the reconstructed mass is affected by linear renormalons in any scheme. The average energy of the $W$ boson (that we consider as a simplified example of leptonic observable) has a renormalon in the narrow-width limit in any mass scheme, that is however screened at large orders for finite top widths, provided the top mass is in the $\overline{\rm MS}$ scheme. The most precise determinations of the top mass are the direct ones, i.e. those that rely upon the reconstruction of the kinematics of the top-decay products. Direct determinations are heavily based on the use of Monte Carlo event generators. The generators employed must be as much accurate as possible, in order not to introduce biases in the measurements. To this purpose, the second part of the thesis is devoted to the comparison of several NLO generators, implemented in the {\tt POWHEG BOX} framework, that differ by the level of accuracy employed to describe the top decay. The impact of the shower Monte Carlo programs, used to complete the NLO events generated by {\tt POWHEG BOX}, is also studied. In particular, we discuss the two most widely used shower Monte Carlo programs, i.e. {\tt Pythia 8.2} and \{\tt Herwig 7.1}, and we present a method to interface them with processes that contain decayed emitting resonances. The comparison of several Monte Carlo programs that have formally the same level of accuracy is, indeed, a mandatory step towards a sound estimate of the uncertainty associated with $m_t$.

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Begg, Rachel. « Banning Bottled Water in Concord, MA : How an Apolitical Commodity Became Political ». Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/30700.

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This thesis paper explores how various actors gathered around bottled water when a ban was put into place in Concord, Massachusetts. The objective has been to answer the following questions: How does an apolitical commodity become a political one? Specifically, how does bottled water move from being an apolitical commodity to become a highly political one? What does this mean for environmental politics? I situate my theoretical approach within Martha Kaplan’s research with fountains and coolers. I use Bruno Latour to show in which ways this ban became a matter of concern, as well as how the ban and the plastic bottle are actors. I conducted fieldwork in Concord and I interviewed participants. My findings reveal that the ban brought meanings to the surface and challenged them or supported them in various ways. The discussions turned from the impact of bottled water on our environment to the political impact of bottled water companies and large corporations on local Concord issues.

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Reif, Danielle. « Die Ästhetik der Leerstelle : Raymond Federmans Roman "La fourrure de ma tante Rachel" vor dem Hintergrund des Gesamtwerks / ». Würzburg : Königshausen & ; Neumann, 2005. http://www.loc.gov/catdir/toc/fy0607/2005441425.html.

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Garali, Imène. « Aide au diagnostic de la maladie d’Alzheimer par des techniques de sélection d’attributs pertinents dans des images cérébrales fonctionnelles obtenues par tomographie par émission de positons au 18FDG ». Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4364/document.

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Dans le cadre de cette thèse, nous nous sommes intéressés à l’étude de l’apport d’une aide assistée par ordinateur au diagnostic de certaines maladies dégénératives du cerveau, en explorant les images de tomographie par émission de positons, par des techniques de traitement d’image et d’analyse statistique.Nous nous sommes intéressés à la représentation corticale des 116 régions anatomiques, en associant à chacune d’elles un vecteur d’attribut issu du calcul des 4 premiers moments des intensités de voxels, et en y incluant par ailleurs l’entropie. Sur la base de l’aire de courbes ROC, nous avons établi qualitativement la pertinence de chacune des régions anatomiques, en fonction du nombre de paramètres du vecteur d’attribut qui lui était associé, pour séparer le groupe des sujets sains de celui des sujets atteints de la maladie d’Alzheimer. Dans notre étude nous avons proposé une nouvelle approche de sélection de régions les plus pertinentes, nommée "combination matrix", en se basant sur un système combinatoire. Chaque région est caractérisée par les différentes combinaisons de son vecteur d’attribut. L’introduction des régions les plus pertinentes(en terme de pouvoir de séparation des sujets) dans le classificateur supervisé SVM nous a permis d’obtenir, malgré la réduction de dimension opérée, un taux de classification meilleur que celui obtenu en utilisant l’ensemble des régions
Our research focuses on presenting a novel computer-aided diagnosis technique for brain Positrons Emission Tomography (PET) images. It processes and analyzes quantitatively these images, in order to better characterize and extract meaningful information for medical diagnosis. Our contribution is to present a new method of classifying brain 18 FDG PET images. Brain images are first segmented into 116 Regions Of Interest (ROI) using an atlas. After computing some statistical features (mean, standarddeviation, skewness, kurtosis and entropy) on these regions’ histogram, we defined a Separation Power Factor (SPF) associated to each region. This factor quantifies the ability of each region to separate neurodegenerative diseases like Alzheimer disease from Healthy Control (HC) brain images. A novel region-based approach is developed to classify brain 18FDG-PET images. The motivation of this work is to identify the best regional features for separating HC from AD patients, in order to reduce the number of features required to achieve an acceptable classification result while reducing computational time required for the classification task

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Dhaynaut, Maëva. « PET imaging for the characterization of tauopathies : Alzheimer's disease and chronic traumatic encephalopathy ». Electronic Thesis or Diss., Sorbonne université, 2019. http://www.theses.fr/2019SORUS197.

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Les tauopathies sont des maladies neurodégénératives caractérisées par une agrégation intracérébrale de protéines Tau anormales. Au cours de ce travail doctoral, nous avons étudié par tomographie par émission de positons (TEP) l'imagerie des agrégats Tau dans la maladie d'Alzheimer (MA) et l'encéphalopathie traumatique chronique (ETC). Notre premier objectif était de déterminer la capacité de l’imagerie Tau-TEP à améliorer le diagnostic de la MA et de déterminer la viabilité d’un nouveau traitement potentiel. Nous avons établi que l'imagerie Tau-TEP était capable de détecter l'effet bénéfique d'une stimulation cérébrale non invasive, appelée stimulation transcrânienne à courant alternatif (tACS) chez les personnes atteintes de MA. Notre deuxième objectif était de déterminer l'utilité de l'imagerie Tau in vivo dans une population de joueurs de football américains pour aider à la détection précoce de l’ETC. Nous avons démontré que l’imagerie Tau était en mesure de mettre en évidence les premières étapes de la maladie. En outre, nous avons étudié par autoradiographie post-mortem chez des patients diagnostiqués MA et ETC, le schéma de liaison de [18F]-AV-1451 avec [18F]-MK-6240 et [18F]-PI-2620 dans les mêmes échantillons. Ces trois traceurs ont montré un modèle similaire de forte liaison à la protéine Tau dans la MA et un manque de liaison dans le cas de l’ETC. Au total, ces expériences ont permis de confirmer l'utilité potentielle de l’imagerie Tau-TEP pour la détection, quantification des agrégats de Tau avec le suivi de la progression de la maladie dans la MA, tout en restant incertain pour l’ETC
Tauopathies are neurodegenerative diseases characterized by intracerebral aggregation of abnormal Tau proteins. During this university thesis, we studied by Positon Emission Tomography (PET) imaging the Tau burden in Alzheimer’s Disease (AD) and Chronic Traumatic Encephalopathy (CTE), two different taupotahies with similar Tau isoforms. In this context, our first objective was to determine the ability of Tau PET imaging to improve the diagnosis of AD and to determine the viability of a new potential treatment. We have established that Tau PET imaging was able to detect the beneficial effect of a non-invasive brain stimulation, called transcranial alternating current stimulation (tACS) in people with AD. Our second objective was to determine the usefulness of Tau PET imaging in vivo in a population of American football players to help the early detection of CTE. We have demonstrated that in our population, Tau PET imaging was able to highlight the Tau pathology in early stages of CTE. In parallel, we have studied by autoradiography post-mortem from patients with neuro-pathological diagnosis of AD and CTE the binding pattern of three radiotracers widely used in research for Tau imaging. We directly compared the binding properties of [18F]-AV-1451 with [18F]-MK-6240 and [18F]-PI-2620 in the same specimens. These three tracers showed similar strong binding pattern to Tau protein in AD and a lack of binding in CTE brain slices. In total, these experiments allow to confirm the potential utility of Tau PET tracers for the reliable detection, quantification of Tau aggregates and disease-progression tracking in AD, while it remains questionable for CTE

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Santos, Rui Pedro Alface. « Ensaios Não Destrutivos para Compósitos Produzidos por Manufatura Aditiva : Avaliação de Termografia Ativa Pulsada e Ultra-sons Sem Contacto ». Master's thesis, 2019. http://hdl.handle.net/10362/80660.

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A utilização de materiais compósitos em aplicações de responsabilidade tem aumentado nas últimas décadas, sobretudo em aplicações onde o peso dos componentes tem um forte impacto económico, como é o caso da indústria aeronáutica e automóvel. Porém com a introdução de novos processos de produção e novos materiais surgem novos defeitos. A presente dissertação pretende avaliar a utilização de técnicas de Ensaios Não Destrutivos (END) por Termografia Ativa Pulsada (TAP) e Air Coupled Ultrasound (ACUS) para compósitos de matriz termoplástica produzidos por Manufatura Aditiva (MA). Para reproduzir os defeitos identificados nestes materiais foram produzidos por Fused Deposition Modeling (FDM) provetes em poliácido láctico (PLA) e poliamida (PA) com delaminações paralelas e perpendiculares ao plano da superfície. Foram também produzidos provetes com várias interfaces e espessuras para avaliar os efeitos da descontinuidade e espessura do material nos resultados obtidos pelos testes de ACUS, bem como provetes para avaliar a possibilidade de deteção de defeitos por difração dos ultra-sons. Desenvolveu-se ainda um protótipo para END, bem como um sistema automatizado para inspeção de superfícies curvas. Dos ensaios realizados conclui-se que a TAP em modo reflexão, quando comparada como o modo transmissão, permite uma melhor identificação de delaminações paralelas ao plano da superfície, desalinhamentos e falta de adesão das fibras de reforço; e que ACUS em modo transmissão permite identificar delaminações paralelas e perpendiculares ao plano da superfície.

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Livres sur le sujet "Top ma"

Toi, ma soeur. Paris : La Martinière, 1998.

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Berger, Karima. Toi, ma sœur étrangère. Paris : Éditions du Rocher, 2012.

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Francois, Thierry. Moi, Мartin - toi, ma femme. Paris : Editions theatrales Art et Comedie, 2000.

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Ton nom dans ma main. Montréal : Éditions du Noroît, 2010.

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ill, Hansen Chris (Christiane), et You Lanlan translator, dir. Ni shi wo de ma ma ma ? Guilin : Li Jiang chu ban she you xian gong si, 2016.

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Ūʺ, Soṅʻʺ Ve. Se kaṃ ma rokʻ sakʻ ma pyokʻ. Ranʻ kunʻ : Sallāvatī Cā pe, 1999.

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Zundel, Maurice. Ton visage, ma lumière : 90 sermons. Paris : Desclée, 1989.

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Solski, R. A toi pour toujours ma Valentine ! [Whitby, ON] : S&S Learning Materials, 1987.

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De ma cage à ton salon. Montréal : Humanitas, 1993.

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Burma. Cheʺ vanʻ thamʻʺ Ññvhanʻ krāʺ reʺ mhūʺ ruṃʺ. Tapʻ ma toʻ Cheʺ tapʻ phvaiʹ Sa muiṅʻʺ. Ranʻ kunʻ] : [Cheʺ vanʻ thamʻʺ Ññvhanʻ krāʺ reʺ mhūʺ ruṃʺ], 2001.

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Plus de sources

Chapitres de livres sur le sujet "Top ma"

Ahbari, Abdellatif, Laila Stour et Ali Agoumi. « Impacts of Climate Change on the Hydro-Climatology and Performances of Bin El Ouidane Reservoir : Morocco, Africa ». Dans African Handbook of Climate Change Adaptation, 2363–86. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-45106-6_245.

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AbstractIn arid and humid contexts, dams’ reservoirs play a crucial role in water regulation and flood control. Under the projected climate change (CC) effects, even a preoptimized management approach (MA) of a reservoir needs to be assessed in this projected climate. This chapter aims to assess the impacts of CC on the Hydroclimatic (HC) variables of the basin upstream the reservoir of Bin El Ouidane (Morocco), and the effects on the performances of its preoptimized MA. The applied Top-Down assessment procedure included CORDEX climate projections, hydrological, siltation, evaporation, and management models. Concerning the HC variables, the results obtained concord with those reported in the literature in terms of trend, but not always in terms of intensity of change. On the other hand, the projections expected a decrease in the performances of the reservoir, except for criterion allocations’ standard deviation, calibrated during the optimization. Also, interesting conclusions have been found like: the change in precipitation dominant form, the accentuation of the pluvial hydrological regime, the advanced snow melting due to the temperature increase. This chapter presents a typical case study on how to use climate projections for reservoir MA adaptation, without being highly and negatively influenced by the climate model uncertainties.

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Poser, William J. « Ma ». Dans Interdisciplinary Approaches to Language, 449–58. Dordrecht : Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3818-5_23.

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Carow-Watamura, U., D. V. Louzguine et A. Takeuchi. « Al-Ma-Zn (075) ». Dans Physical Properties of Ternary Amorphous Alloys. Part 1 : Systems from Ag-Al-Ca to Au-Pd-Si, 288. Berlin, Heidelberg : Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-03481-7_89.

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Bell, Nancy. « Situating Ourselves ». Dans A Student’s Guide to the MA TESOL, 3–22. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_1.

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Bell, Nancy. « Language, Learning, and Teaching ». Dans A Student’s Guide to the MA TESOL, 23–50. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_2.

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Bell, Nancy. « Key Concepts in TESOL ». Dans A Student’s Guide to the MA TESOL, 51–72. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_3.

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Bell, Nancy. « Learning to Learn in Graduate School ». Dans A Student’s Guide to the MA TESOL, 75–93. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_4.

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Bell, Nancy. « Research and the (Future) TESOL Instructor ». Dans A Student’s Guide to the MA TESOL, 95–114. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_5.

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Bell, Nancy. « Professional Development in and beyond Graduate School ». Dans A Student’s Guide to the MA TESOL, 115–29. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_6.

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Bell, Nancy. « Conclusion ». Dans A Student’s Guide to the MA TESOL, 131–32. London : Palgrave Macmillan UK, 2009. http://dx.doi.org/10.1057/9780230245105_7.

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Actes de conférences sur le sujet "Top ma"

Giparakis, Miriam, Hedwig Knötig, Hermann Detz, Maximilian Beiser, Werner Schrenk, Benedikt Schwarz, Gottfried Strasser et Aaron Maxwell Andrews. « Top-Side Illuminated InAs/AlAsSb Quantum Cascade Detector at 2.7 μm ». Dans CLEO : Applications and Technology. Washington, D.C. : Optica Publishing Group, 2022. http://dx.doi.org/10.1364/cleo_at.2022.ath2l.3.

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We present the design, growth, and optical and electrical characterization of an InAs/AlAs0.16Sb0.84 quantum cascade detector at 2.7 μm designed for top-side illumination assisted by a diffraction grating with a room-temperature responsivity of 5.63 mA/W.

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Hsiung, G. Y., C. K. Chan, H. P. Hsueh, T. L. Yang, C. C. Chang, S. N. Hsu, C. Y. Yang, C. L. Chen et J. R. Chen. « Performance of the TLS Vacuum Systems Operated at 300 mA of Top-up Mode ». Dans SYNCHROTRON RADIATION INSTRUMENTATION : Ninth International Conference on Synchrotron Radiation Instrumentation. AIP, 2007. http://dx.doi.org/10.1063/1.2436007.

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Lee, Y. H., B. Tell, K. Brown-Goebeler, J. L. Jewell et J. M. V. Hove. « Low-threshold cw top-surface-emitting lasers at 850 nm ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.mk13.

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We report new self-aligned top-surface-emitting lasers in which top mirrors are used as output mirrors and deep-ion implantation is used for current funneling. The laser structure, grown with molecular-beam epitaxy, is a vertical pin junction in which electric current is injected through the bottom and top mirrors. The undoped active region consists of four 100 Å thick GaAs quantum wells. 300 keV protons are used to introduce a buried damage layer that is concentrated around a depth of 2.3 µm from the surface, but the topmost 1.5 µm is left relatively conductive. Only those areas under the output windows are not damaged, and current is forced to flow predominantly through the active region. A 10 µm diameter laser has a 1.7 mA cw threshold at room temperature. Initially, the laser light is mostly horizontally polarized with a Gaussian mode profile. At higher current, TEM 01* modes show up with both polarizations. We have observed cw output power of as great as 1.5 mW from a 15 µm diameter top-surface-emitting laser. The cw differential quantum efficiency is approximately 20%. Measured spectral linewidth is 0.02 Å as measured by a scanning Fabry-Perot étalon.

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Nguyen, Khanh B., Tai D. Nguyen, Alfred K. Wong, Andrew R. Neureuther et David T. Attwood. « Study of Defects in Multilayer Reflective Coatings for Soft X-ray Projection Lithography Mask ». Dans Soft X-Ray Projection Lithography. Washington, D.C. : Optica Publishing Group, 1993. http://dx.doi.org/10.1364/sxray.1993.ma.7.

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In a soft x-ray/EUV projection lithography system, multilayer reflective coatings consisting of 30-50 bilayers of alternating high-Z/1ow-Z materials would be used on all reflecting surfaces - collection optics, masks, and imaging optics. A reflection mask would likely be a multilayer coating with a top layer of patterned absorber [1, 2]. Since the mask is to be faithfully reproduced on the wafer, any mask defects and imperfections would also be reproduced.

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Wu, Da, Xiao Lang, Di Zhang, Leif Eriksson et Wengang Mao. « A Statistical ARIMA Model to Predict Arctic Environment for NSR Shipping ». Dans ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/omae2021-62783.

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Abstract Reliable sea ice concentration (SIC) information assists the safe and energy-efficient ship navigation along the Northern Sea Route (NSR). In particular, the accurate SIC forecast is a top priority. This study proposes a statistical interpolation method to reduce the errors induced by the traditional interpolation method. An auto-regressive integrated moving average (AR/MA) model is developed based on reanalysis data. The AR/MA model can be used for short-term SIC forecasts along the NSR. Model validation has been conducted through a specially designed cross-validation. The route availability is estimated according to the SIC forecast. The results indicate that the specified NSR will be open for shipping from 2021 to 2024. The work also indicates the feasibility of the proposed statistical models to assist NSR shipping management.

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Grimmer, Jorg O. W., Antonio Alaminos, Mohamed Al Jawhari, Hani Buhindi, Haifa Al Harbi, Laura Cajas et Edmundo Peralta. « Tar Modelling Offshore Abu Dhabi with the Arab Formation as Active Source Rock ». Dans ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211589-ms.

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Abstract This study demonstrates first time in Abu Dhabi the capacity of combined 3D tar and petroleum systems modelling, in an operating oil field offshore Abu Dhabi, indicating locally the tar presence in the Arab formation. It is intended to give insights on the most likely process of tar formation and allows to a certain extent a prediction of tar presence away from well control. The tar modelling is calibrated through core observations on vertical wells, which define the thickness of the initially assumed constant and homogeneous tar mat. An extensive data set using adapted geochemistry, petrographic analyses, fluid inclusion analyses and inclusion PVTX-modelling is used to analyse the charge history of the oil field and its tar in detail. The analysed tar occludes the pore space in the reservoirs of the lower Arab Formation in the oilfield offshore Abu Dhabi. The petrographic analyses indicate the presence of tar particles even up to the upper Arab. Geochemistry and petrography show that there are two different tar types. The classical reservoir filling black tar in the upper most part of the Lower Arab is identified as APE (asphaltene precursor entity after Wilhelms & Larter, 1994) tar which is caused by a flocculation process at a certain temperature and pressure regime in the reservoir. This concept has been successful modelled and can even explain the observed fine tar particles up to the upper most Arab. The second type of initially called "tar" is analysed and observed in the top Diyab and lowest part of the Arab, in a micritic limestone facies environment. Previous concepts struggled to justify the black tar deposition in the dense micritic carbonate mudstones. The initial porosity in this micritic mudstones was already very low and therefore a tar flocculation process or gravity segregation in such an environment urges for other explanations. Our analyses indicate that the micritic mudstone acts as a source rock at the top of Diyab and the lower most Arab subunit, where the early heavy oil and asphaltenes (POA=pre-oil asphaltenes) did not leave the rock and stayed in-situ as bitumen/black tar. This has been modelled with a tar specific kinetics, differentiating in an early heavy oil component (POA), that is generated in-situ and an asphaltene component (APE) expelled within the oil and transported into the reservoir. Acceptable tar modelling result have been reached by reconstructing the charge history of the field. It shows that Diyab oil entered the lower Arab reservoir at approx. 105/95 Ma. The tar modelling through time shows that first tar deposited at 78 Ma (+/- 5 Ma) in the southern part of the oil field. The charge modelling indicates the lower Arab seal failure at approx. 58/53 Ma in the past. The shallower reservoir units of the lower and middle Arab up to the upper Arab are subsequently filled with asphaltene rich oil. Then at 48 Ma the asphaltenes reach a flocculation peak. Finally at 47/34 Ma the whole oil field with the already flocculated tar (APE in the reservoir) and the asphaltenes in the source rock (POA) received a paleo heat shock of at least 140°C, which transformed the tar into pyrobitumen and caused the today surprisingly high API (around 40°API) in the oil field by oil-to-gas cracking.

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Noh, Jinhyun, Mengwei Si, Hong Zhou, Marko J. Tadjer et Peide D. Ye. « The Impact of Substrates on the Performance of Top-Gate p-Ga203 Field-Effect Transistors : Record High Drain Current of 980 mA/mm on Diamond ». Dans 2018 76th Device Research Conference (DRC). IEEE, 2018. http://dx.doi.org/10.1109/drc.2018.8442276.

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Carlson, Timothy H. « EVIDENCE FOR SECONDARY SITES OF HEPARIN BINDING TO ANTITHROMBIN III (AT) ISOFORMS ». Dans XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643681.

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AT exists as two isoforms differing in affinity for heparin (Thromb Res 27:23,1982; JBC 260:610,1985). The binding of human AT isoforms to commercial heparin, or purified unbleached heparin was studied. These heterogeneous, mixed-affinity (MA) heparins were coupled to agarose. When columns of these resins were eluted with NaCl gradients, after mixtures of the higher (ATvh) and lower (ATh) affinity isoforms of AT had been applied, ATvh always eluted after ATh. To determine the nature of this difference, low-affinity (LA) heparin was prepared by repeated passage of MA heparin over an ATh-ConA-Sepharose column. Neither AT isoform bound during passage over a LA-heparin agarose column equilibrated with 0.15 M NaCl. However, the ATvh was significantly retarded, while ATh eluted at about the same position as BSA. To demonstrate that ATh also interacts with a LA-site on heparin, a column containing MA heparin was loaded with ATh until the effluent concentration reached a steady state. Under the conditions, 21 mg of ATh was associated with the column in the steady state. Of this 10 mg eluted during a wash with 0.15 M NaCl, and 11 mg with 1.5 M NaCl elution. When the same experiment was performed using ATvh in place of ATh, approximately 25% more ATvh bound in both the steady state and to the washed column. To demonstrate that a secondary interaction is responsible for the separation of ATvh and ATh during heparin-agarose chromatography, the isoforms were applied together to MA-heparin columns in less than saturating amounts. When NaCl gradients were used to elute the columns in a reverse direction (bottom to top of column), ATh and ATvh co-eluted at relatively low salt concentrations. Thus, separation results during filtration of ATh and ATvh through the columns, after neutralization of the HA interaction. Finally, to determine if ATh and ATvh compete for the same binding sites on heparin, a MA-heparin column was loaded with a saturating amount of ATh. When ATvh was applied to this column, ATh was quantitatively displaced. It is concluded that (1) both AT isoforms bind LA sites on heparin (2) heparin contains many more LA sites than the HA ones; (3) ATvh binds more strongly to LA sites than ATh; and (4) LA binding may enhance activation of AT at the HA site by increasing the rate at which AT binds to this site.

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Lee, Y. H., J. L. Jewell, S. L. Mccall, S. J. Walker, A. Scherer, L. T. Florez et J. P. Harbison. « Room temperature continuous operation of vertical cavity microlasers ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.mhh4.

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The microlaser structure has a top p-doped mirror, a full wave thick spacer with three InGaAs quantum wells, and an n-doped bottom mirror, all grown by molecular beam epitaxy. The structure was designed for 980 nm. Chemical beam ion-beam assisted etching was used to generate various sizes of square mesas (5, 10, 25, 50, 100, 200 µm). Deep (5-µm deep) and shallow (2.5-µm deep) etchings were tried and compared. Shallow etched samples generally showed better thermal and spectral characteristics. Pulsed threshold currents are the same for both. Continuous lasing was observed for 10- and 25-µm mesas with 4- and 13-mA current, respectively. In pulsed operation, the threshold currents are 2.0,4.0,10,30,120 mA for 5-, 10-, 25-, 50-, 100-µm mesas, respectively. For mesas smaller than 25 µm, the threshold current increases linearly with mesa linear dimension. This linear dependence is explained by a strong surface recombination for these small mesas. For the larger ones, the threshold current increases linearly with mesa area at 1.2 kA/cm2. With this current density and proper passivation of the side walls of the smaller mesas, one should achieve 300-µA threshold current for a 5-µm mesa. The maximum peak power was 86 mW from a 100-µm mesa at 980 nm.

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Jewell, Janet L., Y. H. Lee, S. Walker, A. Scherer, J. P. Harbison, L. T. Florez et S. L. Mccall. « Low threshold electrically pumped vertical cavity surface emitting microlasers ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.tup6.

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We report electrically pumped lasing at room temperature in microresonators 2-5 µm in diameter. The active media were three quantum wells of 80-Å In0.2Ga0.8As with 100-Å barriers. The mirrors were GaAs/AlAs quarterwave stacks with 20.5 pairs on the bottom n-doped and 12 pairs, p-doped, on top. Additionally, the top mirror had a fraction of a quarterwave AlAs, 30-Å δ-doped GaAs, and was capped by 1500-Å Au. The semiconductor heterostructure was grown by molecular beam epitaxy, and chemical beam ion-beam assisted etching etched through the Au cap and the >5-µm heterostructure. The substrate backside was polished and grounded while an electrical probe contacted the Au cap. The <2-Å wide 958-nm output was linearly polarized. With 50-ns pulses a 3-µm device had a 1.3-mA threshold with ~15% internal slope efficiency on a linear slope. We attained duty cycles >25%. Resistance was very high, ~10 kΩ due to its small diameter, probe contact, and well/ barrier nature of the mirrors. Use of a single quantum well and surface passivation should reduce thresholds to ~10 µA, making such resistances tolerable and allow cw operation.

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Rapports d'organisations sur le sujet "Top ma"

Bland, Simon Nicholas, Ryan D. McBride, David Franklin Wenger, Daniel Brian Sinars, Jeremy Paul Chittenden, Sergei A. Pikuz, Eric Harding et al. Scaling of X pinches from 1 MA to 6 MA. Office of Scientific and Technical Information (OSTI), septembre 2010. http://dx.doi.org/10.2172/1011205.

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Thomas, M. D. Magnetic and gravity characteristics of the Thelon and Taltson orogens, northern Canada : tectonic implications. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329250.

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Differences of opinion concerning the relationship between the Thelon tectonic zone and the Taltson magmatic zone, as to whether they are individual tectonic elements or two independent elements, have generated various plate tectonic models explaining their creation. Magnetic and gravity signatures indicate that they are separate entities and that the Thelon tectonic zone and the Great Slave Lake shear zone form a single element. Adopting the single-element concept and available age dates, a temporally evolving plate tectonic model of Slave-Rae interaction is presented. At 2350 Ma, an Archean supercontinent rifted along the eastern and southern margins of the Slave Craton. Subsequent ocean closure, apparently diachronous, began with subduction at 2070 Ma in the northern Thelon tectonic zone, followed by subduction under the Great Slave Lake shear zone at 2051 Ma. Subduction related to closure of an ocean between the Buffalo Head terrane and the Rae Craton initiated under the Taltson magmatic zone at 1986 Ma, at which time subduction continued along the Thelon tectonic zone. At 1970 Ma, collision in the northern Thelon tectonic zone is evidenced in the Kilohigok Basin. From 1957 to 1920 Ma, plutonism was active in the Taltson magmatic zone, Great Slave Lake shear zone, and southern Thelon tectonic zone. The plutonism terminated in the northern Thelon tectonic zone at 1950 Ma, but it resumed at 1910 Ma and continued until 1880 Ma. The East Arm Basin witnessed igneous activity as early as 2046 Ma, though this took place more continuously from 1928 to 1861 Ma; some igneous rocks bear subduction-related trace element signatures. These signatures, and the presence of northwest-verging nappes, may signify collision with the Great Slave Lake shear zone as a result of southeastward subduction, completing closure between the Slave and Rae cratons.

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Anderson, R. G., et I. Reichenbach. U - Pb and K - Ar Framework For Middle To Late Jurassic [172 - . 158 Ma] and Tertiary [46 - 27 Ma] Plutons in Queen Charlotte Islands, British Columbia. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/131963.

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Ray Tomlin. Beam Effects from an Increase of LINAC Current from 40 ma to 49 Milliamperes. Office of Scientific and Technical Information (OSTI), juin 2002. http://dx.doi.org/10.2172/795137.

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Tuck, Gary. Visit to Ionospheric Modeling and Remote Sensing Branch, Phillips Laboratory in Hanscom AFB, MA. Fort Belvoir, VA : Defense Technical Information Center, novembre 1994. http://dx.doi.org/10.21236/ada292339.

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D. Buesch. Decreasing Slip Rates From12.8 Ma to Present on the Solitario Canyon Fault at Yucca Mountain, Nevada. Office of Scientific and Technical Information (OSTI), juillet 2006. http://dx.doi.org/10.2172/893888.

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Fallas, K. M., et W. Matthews. Age dating of a bentonite in the Duo Lake Formation, western Mackenzie Mountains, Northwest Territories. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328830.

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In the Misty Creek Embayment of the western Mackenzie Mountains, Duo Lake Formation locally includes minor volcanic deposits associated with Marmot Formation volcanism. A bentonite layer from an outcrop of graptolitic shale found in NTS map area 106-B, in the upper part of the Duo Lake Formation, was sampled for U-Pb zircon dating. Analytical results yielded a dominant population of grains with a concordia age of 439.8 ± 3.0 Ma, interpreted as the age of deposition. Minor inherited zircon populations yielded ages ranging from approximately 1200 to 2850 Ma. Observed graptolites from the same outcrop likely range from Middle Ordovician to Early Silurian and are compatible with the interpreted U-Pb age of the bentonite. Previously known Middle and Late Ordovician volcanic activity in the Misty Creek Embayment is here expanded to include Early Silurian activity, and serves as a proxy for the timing of active extensional tectonism in the basin.

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Turner, E. C. Mesoproterozoic Borden Basin, northern Baffin Island. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/321825.

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The unmetamorphosed and nearly undeformed late Mesoproterozoic Borden Basin on northern Baffin Island exhibits sag, rift, and foreland-basin-like phases. A thin, partly subaqueous basal basalt is overlain by mature shallow-marine quartz arenite, upward-deepening siltstone and shale (marking the beginning of rifting), a complex suite of rift-delineated carbonate units containing two dramatic internal unconformities, and a flysch-molasse-like succession containing evidence of sediment derivation from the Grenville Orogen. Geochronological data indicate that deposition of most of the succession took place ca. 1100 to 1050 Ma. One of the carbonate intervals, Nanisivik Formation, is the main host of regional Zn-Pb showings including the past-producing Nanisivik orebody, which formed in the late Mesoproterozoic from low-temperature fluids, and which was emplaced under strong structural and stratigraphic controls. Minimal postdepositional deformation is limited to the emplacement of mafic dykes ca. 720 Ma and repeated reactivation of basement-rooted normal faults.

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Thomas, M. D. Magnetic and gravity models, northern half of the Taltson Magmatic Zone, Rae Craton, Northwest Territories : insights into upper crustal structure. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/328244.

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A prominent magnetic low along an eastern portion of the Paleoproterozoic Taltson magmatic zone (TMZ) correlates mainly with the youngest granitoid in the zone, the peraluminous ca. 1936 Ma Konth granite. Flanking belts of higher magnetic intensity coincide mainly with slightly older Taltson plutonic rocks (e.g. ca. 1986 Ma Deskenatlata granodiorite, ca. 1955 Ma Slave granite) to the west and Neoarchean and/or Paleoproterozic gneisses of the Rae Craton to the east. A prominent gravity low along a portion of the northeastern margin of the TMZ correlates mainly with the Konth granite. Modelling of east-west magnetic and gravity profiles crossing the TMZ is used to investigate the geometrical and geological significance of these signatures. Modelling of the gravity low revealed a basin-like shape, with a maximum thickness of 14.9 km, for a composite unit of Konth-Slave magmatic suites. Magnetic modelling, the preferred technique north and south of the gravity minimum, yielded basin-like shapes for an essentially nonmagnetic Konth-Slave unit, but with much smaller maximum thicknesses of 5.0 and 6.5 km, respectively. Farther south in the TMZ, strongly magnetic units within mapped Konth and Slave granites preclude definition of a nonmagnetic Konth-Slave unit. Aside from the Slave unit, most other modelled magnetic units are generally steep and narrow and have fairly large magnetic susceptibilities. They are modelled to a depth of 6.2 km below sea level and have a steeply dipping, near-surface structural fabric extending to significant depth. Granitoids in the TMZ have previously been designated as ilmenite series or magnetite series, but modelled susceptibilities indicate that revisions to some designations may be required.

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Parrish, R. R., et R. L. Armstrong. The Ca. 162 Ma Galena Bay Stock and Its Relationship To the Columbia River Fault Zone, Southeast British Columbia. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/122743.

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