Letteratura scientifica selezionata sul tema "Cyclist Corps"
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Articoli di riviste sul tema "Cyclist Corps"
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Keyes, P. L., J. L. Kostyo e R. Towns. "The autonomy of the rabbit corpus luteum". Journal of Endocrinology 143, n. 3 (dicembre 1994): 423–31. http://dx.doi.org/10.1677/joe.0.1430423.
Testo completoAbstract (sommario):
Abstract The rabbit corpus luteum possesses LH receptors that are coupled to adenylyl cyclase, but paradoxically it does not require LH as a luteotrophic factor for the maintenance of progesterone secretion. This suggests that rabbit luteal cells may not respond physiologically to LH. Therefore, the present study was undertaken to investigate the responsiveness of the rabbit corpus luteum of pseudopregnancy to human chorionic gonadotrophin (hCG) which acts on the same receptor as LH. Pseudopregnancy was induced by injection of 40 IU pregnant mare serum gonadotrophin followed 50 h later by an injection of 40 IU hCG (day 0). On days 7 and 11 of pseudopregnancy, corpora lutea were obtained and incubated for 2 or 5 h in the presence of either 0·1 or 1 μg/ml hCG or 1 mm monobutyryl cyclic AMP (bcAMP). Neither hCG nor bcAMP stimulated progesterone production by the isolated corpus luteum, despite a sustained high rate of progesterone production by the tissue throughout the incubation period. By contrast, Graafian follicles removed from the same ovaries and incubated under the same conditions responded both to hCG and bcAMP with large increases in progesterone production. To determine whether the cyclic AMP content of the corpus luteum was altered by in vitro exposure to hCG, day 7 and day 11 corpora lutea were incubated for 5 or 15 min with various concentrations of hCG, and cyclic AMP in the tissue was then measured. Even at the highest concentration of hCG tested (10 μg/ml), the cyclic AMP content of the corpus luteum was unaltered. Given this result, the acute effects of various concentrations of hCG on the adenylyl cyclase activity of homogenates of day 11 corpora lutea were examined. Consistent with previous reports of others, adenylyl cyclase activity was stimulated, but only at a high concentration of hCG (1 μg/ml), and the degree of stimulation of the enzyme (∼75%) was quite modest. By contrast, the adenylyl cyclase activity of homogenates of rabbit Graafian follicles was stimulated by even the lowest concentration of hCG tested (0·01 μg/ml). Thus, the adenylyl cyclase of the rabbit follicle is much more sensitive to hCG stimulation than the luteal form of the enzyme. Given the poor responsiveness of luteal adenylyl cyclase to hCG, the possibility was considered that cyclic AMP production in response to hCG might be obscured by luteal cell phosphodiesterase. When day 11 corpora lutea were incubated with hCG in the presence of the phosphodiesterase inhibitor, isobutyl methylxanthine (5 mm), there was a marked increase in the cyclic AMP content of the tissue. Despite this large increase in endogenous cyclic AMP, progesterone production by the corpora lutea was again unaffected. Thus, the rabbit corpus luteum is insensitive to stimulation in at least two major respects. The adenylyl cyclase coupled to the LH receptor is resistant to stimulation by LH (hCG), and steroidogenesis, as reflected by progesterone production in vitro, is not stimulated acutely by cyclic AMP. These results suggest that progesterone biosynthesis in the rabbit corpus luteum is not a regulated process, but rather a process that becomes autonomous as a result of the differentiation of granulosa cells into luteal cells. Therefore, the role of a luteotrophin, such as oestrogen in the rabbit, is to maintain the health and viability of the luteal cells, which have, as an intrinsic property, the capacity to produce progesterone at a high rate. Journal of Endocrinology (1994) 143, 423–431
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von Procházka, Azrael A., e T. J. Millar. "Species cycling and the enhancement of ammonia in pre-stellar cores". Monthly Notices of the Royal Astronomical Society 501, n. 1 (1 dicembre 2020): 1228–42. http://dx.doi.org/10.1093/mnras/staa3650.
Testo completoAbstract (sommario):
ABSTRACT The quantity of NH3 produced on grain surfaces in the pre-stellar core is thought to be one of the determining factors regarding the chemical complexity achievable at later stages of stellar birth. In order to investigate how this quantity might be influenced by the gas–grain cycling of molecular material within the cloud, we employ a modified rates gas–grain chemical code and follow the time-dependent chemistry of NH3 as the system evolves. Our models incorporate an updated version of the most recent UDfA network of reaction rate coefficients, desorption from the grains through standard thermal and non-thermal processes, and physisorbed and chemisorbed binding of atomic and molecular hydrogen to a population of carbonaceous and siliceous grains. We find that (1) observable abundances of NH3 can exist in the gas phase of our models at early times when the N atom is derived from CN via an efficient early-time hydrocarbon chemistry, (2) a time-dependent gradient exists in the observational agreement between different species classes in our models, consistent with possible physical substructures within the TMC-1 Cyanopolyyne Peak, and (3) the gaseous and solid-state abundances of NH3 are sensitive to the presence of gas–grain cycling within the system. Our results suggest that the degree of chemical complexity achievable at later stages of the cloud’s chemical evolution is indeed influenced by the manner in which the gas–grain cycling occurs.
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Rojas, Francisco J., Ines Moretti-Rojas, Jose P. Balmaceda e Ricardo H. Asch. "Regulation of gonadotropin-stimulable adenylyl cyclase of the primate corpus luteum". Journal of Steroid Biochemistry 32, n. 1 (gennaio 1989): 175–82. http://dx.doi.org/10.1016/0022-4731(89)90161-1.
Testo completo
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LEVIN, ROBERT M., JOSEPH HYPOLITE e GREGORY A. BRODERICK. "Comparative Studies on Rabbit Corpus Cavernosal Contraction and Relaxation. An In Vitro Study". Journal of Andrology 15, n. 1 (2 gennaio 1994): 36–40. http://dx.doi.org/10.1002/j.1939-4640.1994.tb01680.x.
Testo completoAbstract (sommario):
ABSTRACT: Erectile function (erection and detumescence) involves the complex interaction of direct neuronal stimulation of corporal smooth muscle, neurohumoral release of specific endothelial contractile and relaxant factors, and secondary modulation by a variety of putative neuropeptides and vasoactive modulators including nitric oxide. The specific aim of the current study was to determine the relative contribution of nitric oxide, adrenergic, purinergic, and cholinergic stimulation in the relaxant response to field stimulation. The results demonstrate that virtually all of the inhibitory effects of field‐stimulated relaxation could be explained by the release of nitric oxide. l‐NAME (l‐NG‐nitro arginine methyl ester, a competitive inhibitor of NO synthase) reduced field‐stimulated relaxation by over 95% at all frequencies. Neither atropine nor propranolol (or the combination of the two) had any significant effect on field‐stimulated relaxation. l‐NAME blocked both field‐stimulated relaxation and bethanechol‐stimulated relaxation. However, methylene blue (a guanyl cyclase inhibitor) was significantly more potent at blocking bethanechol‐stimulated relaxation than field‐stimulated relaxation. Neither l‐NAME nor methylene blue had any effect on nitroprusside (a direct liberator of NO) nor ATP‐stimulated relaxation. Isoproterenol had only a minor inhibitory effect on phenylephrine‐contracted tissue. These data suggest that 1) Methylene blue, which inhibits guanyl cyclase, is a relatively poor inhibitor of field‐stimulated relaxation. 2) l‐NAME is a potent inhibitor of NO synthesis and can in a dose‐dependent fashion inhibit over 95% of field‐stimulated relaxation. 3) Equipotent relaxation of corporal smooth muscle can be effected through pharmacologic stimulation with ATP (2 mM), nitroprusside (200 μM), and field stimulation (32 Hz). 4) If purinergic neurotransmission participates in physiologic erection, it does so by a mechanism independent of the l‐Arginine‐NO cGMP pathway.
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Li, Xiang, Hyun Cheol Oh, Su Bin Son, Yun Jung Lee, Dae Gill Kang e Ho Sub Lee. "Effect of an Ethanol Extract ofScutellaria baicalensison Relaxation in Corpus Cavernosum Smooth Muscle". Evidence-Based Complementary and Alternative Medicine 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/148929.
Testo completoAbstract (sommario):
Aims of study. The aim of the present study was to investigate whether an ethanol extract ofScutellaria baicalensis(ESB) relaxes penile corpus cavernosum muscle in organ bath experiments.Materials and methods. Changes in tension of cavernous smooth muscle strips were determined by penile strip chamber model and in penile perfusion model. Isolated endothelium-intact rabbit corpus cavernosum was precontracted with phenylephrine (PE) and then treated with ESB.Results. ESB relaxed penile smooth muscle in a dose-dependent manner, and this was inhibited by pre-treatment with NG-nitro-l-arginine methyl ester (l-NAME), a nitric oxide (NO) synthase inhibitor, and 1H-[1, 2, 4]-oxadiazolo-[4,3-α]-quinoxalin-1-one (ODQ), a soluble guanylyl cyclase (sGC) inhibitor. ESB-induced relaxation was significantly attenuated by pretreatment with tetraethylammonium (TEA), a nonselective K+channel blocker, and charybdotoxin, a selective Ca2+-dependent K+channel inhibitor. ESB increased the cGMP levels of rabbit corpus cavernosum in a concentration-dependent manner without changes in cAMP levels. In a perfusion model of penile tissue, ESB also relaxed penile corpus cavernosum smooth muscle in a dose-dependent manner.Conclusion. Taken together, these results suggest that ESB relaxed rabbit cavernous smooth muscle via the NO/cGMP system and Ca2+-sensitive K+channels in the corpus cavernosum.
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Glatt, Charles E., e Solomon H. Snyder. "Cloning and expression of an adenylyl cyclase localized to the corpus striatum". Nature 361, n. 6412 (febbraio 1993): 536–38. http://dx.doi.org/10.1038/361536a0.
Testo completo
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Behrends, Sönke, Anna Steenpass, Hartmut Porst e Hasso Scholz. "Expression of nitric oxide-sensitive guanylyl cyclase subunits in human corpus cavernosum". Biochemical Pharmacology 59, n. 6 (marzo 2000): 713–17. http://dx.doi.org/10.1016/s0006-2952(99)00381-0.
Testo completo
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Thorpe, David S., Shi Niu e Eugene Morkin. "Overexpression of dimeric guanylyl cyclase cores of an atrial natriuretic peptide receptor". Biochemical and Biophysical Research Communications 180, n. 2 (ottobre 1991): 538–44. http://dx.doi.org/10.1016/s0006-291x(05)81098-8.
Testo completo
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Sakagami, Hiroyuki, Yoshihiro Sawamura e Hisatake Kondo. "Ontogenetic expression of corpus striatum-specific adenylyl cyclase in the rat striatum". Neuroscience Research Supplements 19 (gennaio 1994): S101. http://dx.doi.org/10.1016/0921-8696(94)92546-1.
Testo completo
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Christ, George J., Daniel C. Kim, Harvey C. Taub, C. Marjorie Gondré e Arnold Melman. "Characterization of nitroglycerine-induced relaxation in human corpus cavernosum smooth muscle: implications to erectile physiology and dysfunction". Canadian Journal of Physiology and Pharmacology 73, n. 12 (1 dicembre 1995): 1714–26. http://dx.doi.org/10.1139/y95-735.
Testo completoAbstract (sommario):
The importance of the nitric oxide – guanylate cyclase – cGMP system in modulating corporal smooth muscle tone and penile erection has been amply demonstrated. The goal of these studies was to evaluate the possibility that age- or disease-related alterations in human corporal smooth muscle responsivity to activation of this pathway might play a role in the etiology of erectile dysfunction. Thus, we utilized a previously described heuristic model to assess the kinetic and steady-state characteristics of relaxation of precontracted isolated corporal tissue strips elicited by nitroglycerine (NTG). Studies were conducted on corporal tissue strips excised from 26 patients with organic erectile dysfunction, and 7 patients with documented erections. For the purposes of statistical analysis the impotent patient population was stratified into two age groups (A, ≤59 years; B, ≥60 years) and further subdivided into two diagnostic categories, diabetic and nondiabetic patients, respectively. In ≈75% of precontracted corporal tissue strips derived from impotent patients (contracted to ≈75% of maximum with phenylephrine), the NTG-induced response was biphasic, consisting of a rapid relaxation response that reached steady state before onset of a more slowly developing regaining of tension, termed the desensitization response. In contrast, a biphasic response was observed much less frequently (≈30%) in corporal tissue strips derived from a potent patient population (p < 0.0001). Statistical analysis revealed significant heterogeneity among corporal tissue strips derived from patients with organic erectile dysfunction, with respect to both the kinetic and steady-state characteristics of the NTG-induced relaxation and desensitization responses. In particular, the maximal rate constant for both NTG-induced relaxation (krelmax; p < 0.01) and desensitization (kdes; p < 0.03) responses was significantly greater in corporal tissue strips excised from diabetic than nondiabetic patients. Furthermore, the EC50 for NTG-induced relaxation of precontracted corporal smooth muscle strips from potent patients (≈25 nM) was 0.90 log unit less than that for equivalently contracted corporal smooth muscle strips derived from impotent patients (≈180 nM; p < 0.03). Such observations suggest that alterations in corporal smooth muscle responsivity to activation of the guanylate cyclase – cGMP pathway, per se, may be a characteristic of organic erectile dysfunction. In the absence of compensatory changes in other vasodilatory mechanisms, this may contribute to incomplete corporal smooth muscle relaxation and the etiology of erectile dysfunction in some patients.Key words: nitroglycerine, corporal smooth muscle, relaxation, desensitization, guanylate cyclase.
Tesi sul tema "Cyclist Corps"
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Crequy, Samuel. "Analyse accéléromètrique pour l'optimisation de la performance et la prévention des risques en cyclisme". Thesis, Reims, 2015. http://www.theses.fr/2015REIMS021/document.
Testo completoAbstract (sommario):
Le cycliste a toujours souhaité maintenir et/ou améliorer ses performances. Cependant le confort reste un facteur déterminant au vu du temps passé sur le vélo. Ce confort est notamment altéré par les revêtements et les irrégularités du terrain générant des sollicitations le plus souvent néfastes à la santé. Ainsi, la communauté scientifique s'intéresse à la recherche d'un compromis performance-santé. Cet intérêt la mène à exploiter un grand nombre d'outils caractérisés par la mesure d'une grandeur physique. Parmi ces grandeurs, l'accélération apparaît comme une caractéristique riche en information. Elle permet l'analyse de la performance par un suivi de l'athlète et la prévention de la santé par l'évaluation et la limitation des effets délétères. Ces deux aspects, abordés dans ces travaux de thèse, s'appuient sur les concepts généraux de la mécanique des structuresCyclists have always wanted to keep and/or improve their performance. However, comfort is still a determinant factor because of the time spend on the bike. This comfort is especially altered by the coverings and the irregularities of the field generating loads that are often harmful to health. Therefore, the scientific community is interested in the research of a compromise between performance and health. This interest leads it to explore a large amount of tools characterized by the measure of a physical quantity. Among these values, the acceleration appears as a quantity rich in information. It allows to analyse the performance through monitoring of the athlete or the prevention of health disorders by the evaluation and limitation of the harmful effects
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Fernandes, Camila Stéfani Estancial 1989. "Caracterização farmacológica do relaxamento induzido pelos moduladores da guanilato ciclase solúvel em corpo cavernoso isolado de coelho e de rato espontaneamente hipertenso". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312626.
Testo completoAbstract (sommario):
Orientadores: Fabíola Taufic Mónica Iglesias, Edson AntunesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-29T00:02:26Z (GMT). No. of bitstreams: 1 Fernandes_CamilaStefaniEstancial_M.pdf: 2289746 bytes, checksum: e67d3948b14883b515cd7e008bc69850 (MD5) Previous issue date: 2015
Resumo: Duas classes de medicamentos denominadas estimuladores e ativadores da GCs foram desenvolvidas para uso terapêutico em situações patológicas, onde há menor biodisponibilidade NO ou tolerância farmacológica. A principal diferença entre os moduladores da GCs é que os ativadores atuam de maneira mais eficaz mesmo quando a enzima encontra-se no estado oxidado. O presente trabalho foi dividido em duas etapas, a saber: 1) caracterização farmacológica do ativador BAY 60-2770 em corpo cavernoso (CC) de coelho e 2) avaliação do efeito do ativador BAY 60-2770 e estimulador BAY 41-2272 da GCs em CC isolado de ratos espontaneamente hipertensos (SHR) e normotensos (WKY). O BAY 60-2770 promoveu relaxamento concentração dependente em corpo cavernoso de coelho (pEC50: 7,584 ± 0,1923), sendo este efeito potencializado na presença dos inibidores da GCs ODQ (10 µM; pEC50: 8,170 ± 0,1365) e da fosfodiesterase tipo 5 (PDE5), tadalafil (100 ?M; pEC50: 8,381 ± 0,1334). A contração induzida por estimulação elétrica foi reduzida em aproximadamente 50% na presença de BAY 60-2770, sendo este efeito potencializado na presença de ODQ. Em relação ao relaxamento induzido pela estimulação elétrica, o ODQ e BAY 60-2770 aboliu e aumentou, respectivamente o relaxamento. A co-incubação de BAY 60-2770 com ODQ não alterou o relaxamento em comparação com o ODQ sozinho. Curiosamente, quando BAY 60-2770 foi incubado 20 min antes da adição de ODQ, os relaxamentos induzidos por estimulação elétrica foram parcialmente restaurados quando comparado com o ODQ sozinho. Em relação à segunda etapa do trabalho, o relaxamento induzido pelos moduladores da GCs, BAY 60-2770 e BAY 41-2272 não diferiram em CC de ratos SHR comparados ao seu respectivo controle, porém, estes dados não corroboram com a quantificação de GMPc, no qual evidenciamos aumento dos seus níveis em CC de ratos SHR sendo estes níveis ainda maiores quando na presença de ODQ em comparação ao CC de WKY. Observamos também que o relaxamento induzido pela acetilcolina (ACh) encontrou-se reduzido em CC dos animais hipertensos, entretanto, a adição de BAY 60-2770 ou BAY 41-2272 restaurou este relaxamento. Não foi encontrada diferença na expressão das subunidades ?1 e ?1 da GCs em ratos SHR e WKY, porém quando analisamos a expressão da PDE-5, verificamos maior expressão em CC de ratos SHR. O BAY 60-2770 foi capaz de elevar a pressão intracavernosa em CC de ratos normotensos em todas as frequências estudadas, porém esta elevação somente foi significativa na frequência de 16 Hz. Considerando que 1) BAY 60-2770 induziu relaxamento em CC de coelho e de rato hipertenso de maneira mais potente que o estimulador BAY 41-2272, 2) a adição de ODQ potencializou o relaxamento do BAY 60-2770, mas não do BAY 41-2272 em CC de ambas espécies, 3) o aumento dos níveis de GMPc foi maior em CC de ratos SHR após estímulo com BAY 60-2770, mas não com BAY 41-2272 pode-se concluir que em situações patológicas onde há oxidação da GCs e/ou menor biodisponilidade de NO, os ativadores da GCs seriam mais vantajosos que os estimuladores ou inibidores da PDE5 para o tratamento da disfunção erétil
Abstract: Two classes of drugs referred to as stimulators and sGC activators have been developed for therapeutic use in pathological situations where there is less NO bioavailability and pharmacological tolerance. The main difference between the sGC activators modulators is that they act more effectively even when the enzyme is in the oxidized state. This study was divided into two stages: 1) pharmacological characterization of BAY 60-2770 activator in corpus cavernosum (CC) of rabbit and 2) evaluation of the effect of BAY 60-2770 BAY 41-2272 activator and stimulator of GCs isolated from spontaneously hypertensive rats (SHR) and normotensive (WKY). The BAY 60-2770 induced concentration-dependent relaxation in rabbit corpus cavernosum (pEC 50: 7.584 ± 0.1923), and this increased effect in the presence of GCs ODQ inhibitors (10 ?M; pEC 50: 8.170 ± 0.1365) and the phosphodiesterase type 5 (PDE5), tadalafil (100 ?m; pEC50: 8.381 ± 0.1334). The contraction induced by electric stimulation was reduced by approximately 50% in the presence of BAY 60-2770, and this increased effect in the presence of ODQ. In relation to the relaxation induced by electrical stimulation, ODQ and BAY 60-2770 abolished and increased, respectively the relaxation. Co-incubation with BAY 60-2770 with ODQ did not change compared to the relaxation with only ODQ. Curiously, when BAY 60-2770 was incubated 20 minutes before addition of ODQ, the relaxation induced by electric stimulation was partially restored when compared with only ODQ. In the second part, relaxation induced by modulators of GCs, BAY 60-2770 and BAY 41-2272 did not differ in SHR CC compared to their respective control, however, these data do not corroborate the quantification of cGMP, in which we observed an increase in their levels in SHR rats and these levels even higher in the presence of ODQ in comparing the CC of WKY. We also observed a reduction of the relaxation induced by acetylcholine (ACh) in CC of hypertensive animals, however, the addition of BAY 60-2770 or BAY 41-2272 restored this relaxation. There was no difference in the expression of ?1 and ?1 subunits of sGC in SHR and WKY rats, but when we analyzed the expression of PDE-5, we found greater expression in SHR. The BAY 60-2770 was able to raise up the intracavernous pressure in the normotensive rats in all studied frequencies, but this increase was only significant in the frequency of 16 Hz. Considering 1) BAY 60-2770 induced relaxation in rabbit and hypertensive rat so that the most potent stimulator BAY 41-2272, 2) addition of ODQ potentiated relaxation of BAY 60-2770, but not in BAY 41-2272 in CC of both, 3) increased levels cGMP was greater in SHR rats after stimulation with BAY 60-2770, but not in BAY 41-2272 so can be concluded that in pathologic situations where there is oxidation of GCs and / or low bioavailability of NO, would activators of sGC more advantageous than PDE5 inhibitors or stimulators for the treatment of erectile dysfunction
Mestrado
Farmacologia
Mestra em Farmacologia
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Giangreco, Maidana Alejandro José. "Cyclic abelian varieties over finite fields". Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0316.
Testo completoAbstract (sommario):
L'ensemble A(k) des points rationnels d'une variété abélienne A définie sur un corps fini k forme un groupe abélien fini. Ce groupe convient pour des multiples applications, et sa structure est très importante. Connaître les possibles structures de groupe des A(k) et quelques statistiques est donc fondamental. Dans cette thèse, on s'intéresse aux "variétés cycliques", i.e. variétés abéliennes définies sur des corps finis avec groupe des points rationnels cyclique.Les isogénies nous donnent une classification plus grossière que celle donnée par les classes d'isomorphisme des variétés abéliennes, mais elles offrent un outil très puissant en géométrie algébrique. Chaque classe d'isogénie est déterminée par son polynôme de Weil. On donne un critère pour caractériser les "classes d'isogénies cycliques", i.e. classes d'isogénies de variétés abéliennes définies sur des corps finis qui contiennent seulement des variétés cycliques. Ce critère est basé sur le polynôme de Weil de la classe d'isogénie.À partir de cela, on donne des bornes de la proportion de classes d'isogénies cycliques parmi certaines familles de classes d'isogénies paramétrées par ses polynômes de Weil.On donne aussi la proportion de classes d'isogénies cycliques "locaux" parmi les classes d'isogénie définies sur des corps finis mathbb{F}_q avec q éléments, quand q tend à l'infiniThe set A(k) of rational points of an abelian variety A defined over a finite field k forms a finite abelian group. This group is suitable for multiple applications, and its structure is very important. Knowing the possible group structures of A(k) and some statistics is then fundamental. In this thesis, we focus our interest in "cyclic varieties", i.e. abelian varieties defined over finite fields with cyclic group of rational points. Isogenies give us a coarser classification than that given by the isomorphism classes of abelian varieties, but they provide a powerful tool in algebraic geometry. Every isogeny class is determined by its Weil polynomial. We give a criterion to characterize "cyclic isogeny classes", i.e. isogeny classes of abelian varieties defined over finite fields containing only cyclic varieties. This criterion is based on the Weil polynomial of the isogeny class.From this, we give bounds on the fractions of cyclic isogeny classes among certain families of isogeny classes parameterized by their Weil polynomials.Also we give the proportion of "local"-cyclic isogeny classes among the isogeny classes defined over the finite field mathbb{F}_q with q elements, when q tends to infinity
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Peacock, Jerry Edgar. "Marine Corps IT hardware: a method for categorizing and determining technology refreshment cycles". Thesis, Monterey, California: Naval Postgraduate School, 2015. http://hdl.handle.net/10945/45924.
Testo completoAbstract (sommario):
Approved for public release; distribution is unlimitedManagement of information technology (IT) assets within an enterprise is necessary to control organizational costs and ensure that the necessary business requirements are supported. For over 10 years, the Navy Marine Corps Intranet (NMCI) was charged with this task in Navy and Marine Corps IT systems. With the expiration of the NMCI contract, the Marine Corps is now managing its own IT assets. To understand the scope of IT assets to enable better management, this research explores items accounted for within the master data repository, which is aiding in the migration of legacy logistics systems to GCSS-MC. These items and their associated costs are divided into categories to provide a baseline view of Marine Corps IT hardware assets. An equivalent annual cost is applied to assets to suggest a refreshment cycle for laptops, desktops, and servers. This demonstrates a method that can provide IT managers with a means of determining when an asset should be refreshed.
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Forey, Arthur. "Invariants motiviques dans les corps valués". Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066557/document.
Testo completoAbstract (sommario):
Cette thèse est consacrée à définir et étudier des invariants motiviques associés aux ensembles semi-algébriques dans les corps valués. Ceux-ci sont les combinaisons booléennes d'ensembles définis par des inégalités valuatives. L'outil principal que nous utilisons est l'intégration motivique, une forme de théorie de la mesure à valeurs dans le groupe de Grothendieck des variétés définies sur le corps résiduel. Dans une première partie, on définit la notion de densité locale motivique. C'est un analogue valuatif du nombre de Lelong complexe, de la densité réelle de Kurdyka-Raby et de la densité p-adique de Cluckers-Comte-Loeser. C'est un invariant métrique à valeurs dans un localisé du groupe de Grothendieck des variétés. Notre résultat principal est que cet invariant se calcule sur le cône tangent muni de multiplicités motiviques. On établit un analogue de la formule de Cauchy-Crofton locale. On montre enfin que dans le cas d'une courbe plane, la densité motivique est égale à la somme des inverses des multiplicités des branches. L'objet de la seconde partie est de définir un morphisme d'anneau du groupe de Grothendieck des ensembles semi-algébriques sur un corps valué K vers le groupe de Grothendieck de la catégorie d'Ayoub des motifs rigides analytiques sur K. On montre qu'il étend le morphisme qui envoie la classe d'une variété algébrique sur la classe de son motif cohomologique à support compact. Cela fournit donc une notion virtuelle de motif cohomologique à support compact pour les variétés rigides analytiques. On montre également un théorème de dualité permettant de comparer le motif cohomologique de la fibre de Milnor analytique avec la fibre de Milnor motiviqueThis thesis is devoted to define and study some motivic invariants associated to semialgebraic sets in valued fields. They are boolean combinations of sets defined by valuative inequalities. Our main tool is the theory of motivic integration, which is a kind of measure theory with values in the Grothendieck group of varieties defined over the residue field. In the first part, we define the notion of motivic local density. It is a valuative analog of complex Lelong number, Kurdyka-Raby real density and p-adic density of Cluckers- Comte-Loeser. It is a metric invariant with values in a localization of the Grothendieck group of varieties. Our main result is that it can be computed on the tangent cone with motivic multiplicities. We also establish an analog of the local Cauchy-Crofton formula. We finally show that the density of a germ of plane curve defined over the residue field is equal to the sum of the inverses of the multiplicities of the formal branches of the curve. The goal of the second part is to define a ring morphism from the Grothendieck group of semi-algebraic sets defined over a valued field K to the Grothendieck group of Ayoub’s categoryof rigid analytic motives over K. We show that it extends the morphism sending the class of an algebraic variety to the class of its cohomological motive with compact support. This gives a notion of virtual cohomological motive with compact support for rigid analytic varieties. We also show a duality theorem allowing us to compare the cohomological motive of the analytic Milnor fiber with the motivic Milnor fiber
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Normington, Catherine Jane. "Holy women/vulgar women : women and the Corpus Christi cycles". Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297616.
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Rusbridge, Sheila Margaret. "Characterization of the GnRH-induced corpus luteum in the cycling heifer". Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/29977.
Testo completoAbstract (sommario):
Although recent studies in other laboratories have greatly increased our understanding of luteal function in cattle, we are still unable to accurately synchronise luteolysis, preovulatory follicular growth and ovulation with commercially available pharmacological preparations. The aim of these studies was to investigate the factor(s) which controls the formation, function and regression of the GnRH-induced corpus luteum (CL). Initially, we sought to develop an experimental model to examine the characteristics of the CL induced in intact heifers with normal oestrous cyclicity, by GnRH injection in the early luteal phase. Administration of GnRH on Day 6 after the synchronised oestrus resulted in ovulation and formation of an additional CL in >70% of animals. Following prostaglandin F2α(PGF2α) in the mid-luteal phase, the spontaneously-formed CL underwent luteolysis while the induced CL did not, leading to a delay in return to oestrus associated with a persistence of luteal function. Having demonstrated the ovulatory competence of the dominant follicle of the first follicular wave, and the formation of a functional CL, it was of interest to examine the reason for the premature demise of the induced CL in the GnRH responders when compared to the spontaneously-formed CL. Administration of steroid-stripped bovine follicular fluid (bFF), which suppressed the growth of the dominant follicle, and reduced serum oestradiol concentrations, resulted in a further delay in the return to oestrus and a significant extension in the lifespan of the induced CL, when compared to the untreated responders, and provided circumstantial evidence that oestradiol was the endogenous agent responsible for regression of the induced CL.
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Martel, Guillaume. "Mémoire déclarative et mémoire procédurale : quand et comment s'opère la sélection du système de mémoire adapté ?" Bordeaux 1, 2006. http://www.theses.fr/2006BOR13234.
Testo completoAbstract (sommario):
Les phénomènes de consolidation permettant le maintien d'informations ont pour support des cascades moléculaires ayant un rôle spécifique dans les processus mnésiques. Ainsi, bien que la voie AMPc/PKA/CREB semble nécessaire à la consolidation d'informations, une augmentation de l'activité de cette voie est observée dans des structures mnésiques non nécessaires au stockage d'un type d'information donné. Ce travail de thèse a consisté à préciser le rôle de cette augmentation d'activité lors des processus de consolidation. L'étude de la cinétique de phosphorylation de CREB dans l'hippocampe (Hpc) et le striatum (Str) a révélé que l'Hpc développe une activité biphasique avec un pic précoce et un pic tardif. Les études pharmocologiques ont révélé que seule la phase tardive d'activité est critique pour la sélection du système de mémoire adapté. Le Str présente une activité monophasique avec un pic précoce et transitoire, les effets des modifications de la voie AMPc/PKA/CREB étant différents en fonction de la partie du Str considérée, au moment de l'intervention et du type d'information traité. L'implication différentielle de 2 isoformes d'adénylyl-cyclase dans l'Hpc lors de la consolisation d'informations procédurales et relationnelles a été révélée, caractérisant ainsi l'augmentation de l'activité de la voie AMPc/PKA/CREB lors de la consolidation de ces deux types d'informations. Ce travail suggère que les phénomènes de consolisation permettent la sélection du système de mémoire adapté et qu'un fonctionnement particulier de l'Hpc oriente la stratégie comportementale vers une modalité relationnelle ou procédurale. De plus, la réalisation de l'épreuve modifié en direct ces processus de consolisation, permettant d'adapter la stratégie comportementale. Il faut donc considérer les phénomènes de Consolidation comme des mécanismes flexibles intervenant dans la configuration du réseau cérébral mnésique, permettant une adaptation appropriée à l'environnement.
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Dalawat, Chandan Singh. "Groupes des classes de zéro-cycles sur les surfaces rationnelles définies sur un corps local". Paris 11, 1993. http://www.theses.fr/1993PA112142.
Testo completoAbstract (sommario):
Cette these construit et etudie une application de specialisation pour les zero-cycles sur une surface relative sur un trait. Nous demontrons la surjectivite de cet homomorphisme lorsque le trait de base est henselien. Lorsqu'en plus la dimension cohomologique du corps residuel est inferieure a un, et la fibre generique remplit certaines conditions geometriques, par exemple celle d'etre rationnelle, et la condition arithmetique que l'inertie agit trivialement sur son groupe de picard geometrique, nous etablissons la bijectivite de la specialisation. Cela fournit un moyen pratique pour calculer le groupe des classes de zero-cycles sur une telle surface
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Toque, Haroldo Alfredo Flores. "Estudos funcionais e bioquimicos de vinte analogos do sildenafil em plaquetas humanas, corpo cavernoso e aorta de coelho". [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/309474.
Testo completoAbstract (sommario):
Orientador: Gilberto de NucciTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-11T20:24:02Z (GMT). No. of bitstreams: 1 Toque_HaroldoAlfredoFlores_D.pdf: 1734292 bytes, checksum: a664da49d6a032202e54c1490b0647dc (MD5) Previous issue date: 2008
Resumo: O sildenafil, inibidor específico de PDE5, é utilizado no tratamento da disfunção erétil. Na procura de um inibidor mais potente e seletivo de PDE5, testamos vinte novos análogos do sildenafil (6a-v), caracterizados pela presença de um grupo sulfonil ou de um substituinte n'n'etilendiamina na posição do grupo metil da piperazina. Os objetivos deste trabalho foram: 1) Avaliar a atividade inibitória da PDE5 de plaquetas humanas; 2) Avaliar o efeito relaxante dos análogos do sildenafil em corpo cavernoso de coelho; 3) Avaliar o efeito relaxante dos análogos do sildenafil em anéis de aorta de coelho. Foi utilizado sangue de voluntários sadios para a atividade inibitória da PDE5 e coelhos New Zealand machos (2-3 kg) procedentes do CEMIB-UNICAMP para os estudos funcionais. Os animais foram anestesiados com uretana, o corpo cavernoso e a artéria aorta foram rapidamente removidos. O tecido cavernoso e anéis de aorta foram montados em banho para órgão isolado contendo solução de Krebs (37oC, 95% O2 / 5% CO2). Os tecidos foram ligados a transdutores isométricos conectados a um sistema PowerLab® de aquisição de dados. Nossos resultados mostraram que a atividade inibitória da PDE5 induzida pelos análogos do sildenafil em plaquetas humanas foi de maneira dependente da concentração. Os compostos 6m, 6n e 6q mostraram valores elevados de IC50 para inibir a PDE5 plaquetária, enquanto que os compostos 6a, 6b, 6d, 6g e 6p produziram inibição inferior a 50%. A potência inibitória (IC50) dos compostos 6c, 6e, 6f, 6h, 6i, 6l e 6o foi similar ao sildenafil (IC50: 0,05 µM) com valores variando entre 0,05 e 0,15 µM. Os análogos que derivaram da molécula n'n'etilendiamina (6r, 6s, 6t e 6v) mostraram uma boa atividade inibitória com valores entre 0,20-0,51 µM. Interessantemente, o composto 6u mostrou uma potência de 0,04 µM, o qual representou o menor valor obtido dos análogos do sildenafil. Nos estudos funcionais, todos os análogos do sildenafil, à exceção do análogo 6m, relaxaram preparações de corpo cavernoso de coelho de maneira dependente da concentração. Particularmente, o análogo 6f mostrou o melhor perfil farmacológico no relaxamento, com potência similar ao sildenafil, e pode servir de base para o desenvolvimento de novos inibidores de PDE5 para o tratamento da disfunção erétil. Além disso, nossos resultados mostraram que os análogos do sildenafil produzem relaxamento dependente da concentração em anéis de aorta de coelho com endotélio íntegro ou removido. Somente o análogo 6b e 6m apresentaram valores de potência inferiores quando comparados ao sildenafil em tecidos com endotélio íntegro. A remoção do endotélio ou a adição do LNAME ou do ODQ (inibidor da NO sintase e da guanilil ciclase solúvel, respectivamente) em tecidos com endotélio íntegro, provocou deslocamento à direita para o sildenafil e seus análogos, à exceção do 6r e 6u que não apresentaram diminuição da potência decorrente da inibição do NO, seja pela remoção do endotélio, pela inibição da NO sintase ou pela inibição da guanilil ciclase solúvel. Nossos dados também mostram que o 6r e 6u, em combinação com o BAY 41-2272, aumentam a potência evocada por estes análogos tanto em anéis de aorta com endotélio íntegro ou removido. O relaxamento evocado pelo sildenafil, 6r e 6u não envolve a participação de canais de potássio e de cálcio, nem envolve a formação de prostanóides. As respostas relaxantes destes dois análogos não foram alteradas em tecidos desprovidos de endotélio, mostrando-se independentes da via NO/GMPc. Isto sugere que estes dois análogos podem ser de particular interesse em patologias decorrentes de disfunção endotelial.
Abstract: Sildenafil, a cGMP-specific phosphodiesterase-5 (PDE5) inhibitor, is used for the treatment of erectile dysfunction. In the search for a potent and selective PDE5 inhibitor, new sildenafil analogues (6a-v), characterized by the presence on the sulphonyl group in the 5' position of novel N-4-substituted piperazines or ethylenediamine moiety, were synthesized. The aim of this work was 1) To evaluate the PDE5 inhibitory activity in human platelets; 2) To evaluate the relaxing effect of sildenafil analogues in rabbit corpus cavernosum; 3) To evaluate the relaxing effect of sildenafil analogues in rabbit isolated aorta. Blood from human volunteers were collected and used for PDE5 inhibitory activity and Male New Zealand rabbit (2-3 kg) for functional studies. The rabbits were anaesthetized with urethane and sacrificed. The cavernosal tissue and aortic rings were mounted in organ bath containing Krebs solution (37oC, 95% O2 / 5% CO2). Each tissue was connected to an isometric transducer which was connected to a data acquisition system Powerlab®. Our results showed that sildenafil and its analogues concentration-dependently inhibited PDE5 activity in human platelets. Compounds 6m, 6n and 6q showed higher values of IC50 to inhibit PDE5 of platelets, whereas compounds 6a, 6b, 6d, 6g and 6p did not reach 50% of inhibition. The inhibitory potency of PDE5 for 6c, 6e, 6f, 6h, 6i, 6l and 6o were similar with sildenafil (IC50: 0,05 µM) with values between 0,05-0,15 µM. Derived analogues from n'n' substitution showed great PDE5 inhibitory activity. Interesting, compound 6u exhibited greater IC50 value (0,04 µM). In functional studies, all sildenafil analogues with exception of 6m, relaxed concentration-dependently rabbit corpus cavernosum. Compound 6f exhibited great pEC50 value in corpus cavernosum and could be used as base for developing new PDE5 inhibitors. Moreover, our results showed that sildenafil analogues concentration-dependently relaxed both endothelium-intact and - denuded aortic rings with similar potency values of sildenafil. Compounds 6b and 6m showed lower values of potency when compared to sildenafil in endothelium intact. Endothelium denudation or addition of L-NAME or ODQ (NOS and sGC inhibitors, respectively) caused marked rightward shifts in the curve to sildenafil and its analogues, whereas the relaxation curves for 6r and 6u were not altered after endothelium removal or either by the NO synthase or sGC inhibition. Moreover, our data also suggest that compound 6r and 6u increased the potency values in combination with BAY 41-2272 in both intact and denuded endothelium. The relaxation evoked by sildenafil, 6r and 6u does not involve either calcium or potassium channels or prostanoids formation. The relaxing responses by these compounds were independent of NO/cGMP pathway, suggesting that these compounds may be used in several diseases involving endothelium dysfunction.
Doutorado
Doutor em Farmacologia
Libri sul tema "Cyclist Corps"
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Austin, Ronald J. Cycling to war: The history of the AIF/NZ Cyclist Corps 1916-1919. McCrae, Vic: Slouch Hat Publications, 2008.
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NEW ZEALAND CYCLIST CORPS IN THE GREAT WAR 1914-1918. Naval & Military Press, 2006.
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New Zealand Cyclist Corps in the Great War 1914-1918 (Officers of the Regiment). Naval & Military Press, 2004.
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Correa, Mariana. ENTRAINEMENT COMPLET AU POIDS Du CORPS POUR CYCLISTES: LES MEILLEURS EXERCICES Et ENTRAINEMENTS CALLISTHENIQUES POUR DEVENIR UN FANTASTIQUE CYCLISTE. Createspace Independent Publishing Platform, 2016.
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Correa, Mariana. ENTRAINEMENT COMPLET AU POIDS Du CORPS POUR CYCLISTES SECONDE EDITION: LES MEILLEURS EXERCICES ET ENTRAINEMENTS CALLISTHENIQUES POUR DEVENIR Un FANTASTIQUE CYCLISTE. Createspace Independent Publishing Platform, 2018.
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Correa, Mariana. DU CYCLISTE MOYEN Au CYCLISTE PRODIGIEUX DEUXIEME EDITION: PREPAREZ VOTRE CORPS Et VOTRE ESPRIT POUR LA MEILLEURE SORTIE DE VOTRE VIE. Createspace Independent Publishing Platform, 2018.
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The great bicycle experiment: The Army's historic Black Bicycle Corps, 1896-97. Missoula, Mont: Mountain Press Pub. Co., 2012.
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Ellam, Rob. 7. Reconstructing the past and weathering the future. Oxford University Press, 2016. http://dx.doi.org/10.1093/actrade/9780198723622.003.0007.
Testo completoAbstract (sommario):
Tiny microfossils called Foraminifera form calcium carbonate shells that record the δ18O composition of the seawater in which they grew. These microfossils are found in sea bed sediment cores, and a lot of information from these oxygen isotope records can be extracted. ‘Reconstructing the past and weathering the future’ looks at the methodology used in palaeoclimate studies and explains gain and phase modelling and Milankovitch orbital cycles. Similar isotope temperature records have been constructed from polar ice cores. Atmospheric CO2 composition can be reconstructed from the amount of CO2 dissolved in the ice. A new sub-discipline of clumped isotope geochemistry—‘isotomics’—will have applications far beyond carbonate palaeothermometry.
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Sammons, Benjamin. Device and Composition in the Greek Epic Cycle. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190614843.001.0001.
Testo completoAbstract (sommario):
From a corpus of Greek epics known in antiquity as the “Epic Cycle,” six poems dealt with the same Trojan War mythology as the Homeric poems. Though they are now lost, these poems were much read and much discussed in ancient times, not only for their content but for their mysterious relationship with the more famous works attributed to Homer. This study shows that these lost poems belonged, compositionally, to essentially the same tradition as the Homeric poems. It demonstrates that various compositional devices well-known from the Homeric epics were also fundamental to the narrative construction of these later works. Yet while the “cyclic” poets constructed their works using the same traditional devices as Homer, they used these to different ends and with different results. The essential difference between cyclic and Homeric epics lies not in the fundamental building blocks from which they are constructed, but in the scale of these components relative to the overall construction of poems. This sheds important light on the early history of epic as a genre, since it is likely that these devices originally developed to provide large-scale structure to shorter poems and have been put to quite different use in the composition of the monumental Homeric epics. This study includes many new suggestions about the overall form of lost cyclic epics and about the meaning and context of the few surviving verse fragments.
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Lurcock, Pontus, e Fabio Florindo. Antarctic Climate History and Global Climate Changes. Oxford University Press, 2017. http://dx.doi.org/10.1093/oxfordhb/9780190676889.013.18.
Testo completoAbstract (sommario):
Antarctic climate changes have been reconstructed from ice and sediment cores and numerical models (which also predict future changes). Major ice sheets first appeared 34 million years ago (Ma) and fluctuated throughout the Oligocene, with an overall cooling trend. Ice volume more than doubled at the Oligocene-Miocene boundary. Fluctuating Miocene temperatures peaked at 17–14 Ma, followed by dramatic cooling. Cooling continued through the Pliocene and Pleistocene, with another major glacial expansion at 3–2 Ma. Several interacting drivers control Antarctic climate. On timescales of 10,000–100,000 years, insolation varies with orbital cycles, causing periodic climate variations. Opening of Southern Ocean gateways produced a circumpolar current that thermally isolated Antarctica. Declining atmospheric CO2 triggered Cenozoic glaciation. Antarctic glaciations affect global climate by lowering sea level, intensifying atmospheric circulation, and increasing planetary albedo. Ice sheets interact with ocean water, forming water masses that play a key role in global ocean circulation.
Capitoli di libri sul tema "Cyclist Corps"
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Buhler, Thomas, Matthieu Adam, Hakim Ramdani e Pauline Jobard. "Press Discourse on Cycling Before, During, and After the First Covid-19 Lockdown in France. The Rise of the User-Group Voice". In The Urban Book Series, 71–87. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-45308-3_4.
Testo completoAbstract (sommario):
AbstractIn this chapter we explore what a “crisis” event (here the first lockdown related to Covid-19 in France) means in terms of (i) the balance of power among actors expressing themselves in the daily press and of (ii) the main messages that the more prominent of these actors disseminate. In order to analyze changes in press discourse on city cycling in France, we examine a corpus that spans the period from September 2019 to September 2020, i.e., six months before the first lockdown (March 17, 2020) and five months after the end of the month-long lockdown (May 11, 2020). The discourse analysis has been conducted on 578 press articles from five regional newspapers (Rennes, Montpellier, Besançon, Paris, and Lyon) and one national press title (Libération). This entire corpus was analyzed using textometry, a computer-assisted method for analyzing quantitative textual data. This enables us to identify a discursive change. Two elements characterize that change: (i) the balance between actors who “talk” or who “are talked about” in the articles shifts gradually. During this period, cycling organizations appear to be the actors whose position is strengthened in the media discourse; (ii) these actors are strengthened in their traditional mission of lobbying for cycling, but with a focus on new issues (e.g., wearing a face-covering or not for cyclists, calling for the reopening of green public spaces to allow the transit of bicycles, etc.). The first Covid-19 wave appears to have been the accelerator of a wider process that has led cycling organizations to professionalize since the 2000s, to move away from ecologist, anarchist, and anticapitalist discourses and to promote instead the idea of everyday cycling as a tool for improving public health. The Covid-19 crisis has further established cycling organizations as reference actors for bicycle mobility in French cities.
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Cooley, Oliver, Mihyun Kang e Julian Zalla. "Loose Cores and Cycles in Random Hypergraphs". In Trends in Mathematics, 280–85. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-83823-2_44.
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Swerts, M., R. Merckx e K. Vlassak. "Influence of carbon availability on the production of NO, N2O, N2 and CO2 by soil cores during anaerobic incubation". In Progress in Nitrogen Cycling Studies, 633–39. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-011-5450-5_103.
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Clausen, H. B., C. U. Hammer, J. Christensen, C. Schøtt Hvidberg, D. Dahl-Jensen, M. Legrand e J. P. Steffensen. "1250 Years of Global Volcanism as Revealed by Central Greenland Ice Cores". In Ice Core Studies of Global Biogeochemical Cycles, 175–94. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-51172-1_9.
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Anderson, L., R. Parsons e D. W. Hopkins. "An Open Gas-Flow System for Investigating the Response of Nitrous Oxide Fluxes from Soil Cores to Different Oxygen Concentrations". In Progress in Nitrogen Cycling Studies, 507–11. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-011-5450-5_82.
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Kudo, A., R. M. Koerner, D. A. Fisher, J. Bourgeois, D. C. Santry, Y. Mahara e M. Sugahara. "Plutonium from Nagasaki A-Bomb as a Possible Tracer for Global Transport, Using Existing Initial Conditions and Ice Cores". In Ice Core Studies of Global Biogeochemical Cycles, 417–25. Berlin, Heidelberg: Springer Berlin Heidelberg, 1995. http://dx.doi.org/10.1007/978-3-642-51172-1_22.
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Ottobre, J. S., R. L. Stouffer, C. A. VandeVoort e A. C. Ottobre. "Relaxin Secretion by the Primate Corpus Luteum During Simulated Early Pregnancy in Hyperstimulated Menstrual Cycles". In Signaling Mechanisms and Gene Expression in the Ovary, 348–53. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/978-1-4612-3200-1_40.
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Boutron, Claude, Carlo Barbante, Sungmin Hong, Kevin Rosman, Michael Bolshov, Freddy Adams, Paolo Gabrielli et al. "Heavy Metals in Antarctic and Greenland Snow and Ice Cores: Man Induced Changes During the Last Millennia and Natural Variations During the Last Climatic Cycles". In Persistent Pollution – Past, Present and Future, 19–46. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-17419-3_3.
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Gray, Douglas. "Mystery Cycles I: Old Testament". In Later Medieval English Literature, 599–632. Oxford University PressOxford, 2008. http://dx.doi.org/10.1093/oso/9780198122180.003.0022.
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Abstract The (admittedly fragmentary) records suggest that the English cycle plays began to emerge c.1375. About their genesis and development there is little agreement, and the plain truth is that conclusive evidence is lacking for any of the various theories that have been put forward. Among these are the suggestions that the mystery cycles represent a new kind of drama, distinct from liturgical drama and other kinds, which came into existence in the fourteenth century because of the stimulus given by the institution of the feast of Corpus Christi; that they did not spring parentless into existence, but developed from earlier liturgical plays; that the doctrinal Eucharistic connection with the feast of Corpus Christi is incidental, but that they develop from fourteenth-century festival processions.
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Bedoui, Sana, Elhoucine Essefi e Younes Hamed. "Multidisciplinary Study of Cores From the Wetland of El Melah, Southwestern Tunisia". In Practice, Progress, and Proficiency in Sustainability, 215–29. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-7998-9498-8.ch013.
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Saline systems are candidates to be threatened by climatic change. In terms of methodology and materials, color identification, geochemistry, and mineralogy analysis were used. The spectral analysis of data of the amount of active K and Na firstly shows the individualization of a cycle stretching along with 1000 yr. Then, a less pronounced cycle of 2500 years is marked with a lower intensity. Also, on the spectral analysis of K data, the drowned cycles of 650 and 500 years are marked by weak intensities not reaching the threshold level. These two comparable cycles may be artifacts due to analysis errors or variability in the rate of sedimentation resulting in the bifurcation of two hybrid cycles from one real cycle. This work confirmed the cycles found by color studies through real analyses such as geochemical and magnetic measurements. As a matter of fact, the majority of cycles found out by the spectral analysis of colors data are confirmed through analyses.
Atti di convegni sul tema "Cyclist Corps"
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Zaretsky, Erwin V., e Robert E. deLaneuville. "MMC Life System Development (Phase I): A NASA/Pratt & Whitney Cooperative Program". In ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0073.
Testo completoAbstract (sommario):
Abstract Pratt & Whitney Aircraft and NASA Lewis Research Center studied a silicon-carbide-fiber-reinforced, titanium-metal-matrix (MMC) composite designated SiC(SCS-6)/Ti-15V-3Cr-3Al-3Sn. Fracture tests of three nominal 15.24-cm (6-in.) diameter SCS–6/Ti-15-3 rings at 427 °C (800 °F) and room temperature resulted in failure at internal pressures of 0.172 GPa (25 ksi) (average) and 0.235 GPa (34.1 ksi), respectively. Predictions of internal pressure to failure varied from 0.140 to 0.276 GPa (20.3 to 40.1 ksi) at 427 °C (800 °F). Nondestructive evaluation revealed that the rings’ MMC cores had varying density and were not uniformly distributed inside the monolithic casing. Analytical predictions of ring cyclic life at 0.154-GPa (22.4-ksi) internal pressure varied from 1000 to 15 000 cycles. No fatigue life data were obtained with the MMC rings for comparison with theory.
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Pires da Costa, L. "Tensile behaviour of rayon cords in different conditions". In AIMETA 2022. Materials Research Forum LLC, 2023. http://dx.doi.org/10.21741/9781644902431-22.
Testo completoAbstract (sommario):
Abstract. Different polymeric fibrous materials, such as polyester, nylon, aramid and rayon, can be employed as reinforcement in tyres or in other rubber composites. The present contribution focuses on the experimental characterization of rayon yarns and cords and makes some steps towards developing a constitutive model for cords, to be later integrated into a finite element procedure for the analysis of fibre-reinforced composites. Uniaxial tensile tests under monotonic and cyclic loading together with creep tests have been performed on rayon specimens in different conditions. A simple, preliminary viscoelastic-viscoplastic model is proposed which can describe the main experimental findings for untwisted yarns.
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Saleem, Summra, Aniqa Dilawari, Muhammad Usman Ghani Khan e Muhammad Husnain. "Voice Conversion and Spoofed Voice Detection from Parallel English and Urdu Corpus using Cyclic GANs". In 2019 International Conference on Robotics and Automation in Industry (ICRAI). IEEE, 2019. http://dx.doi.org/10.1109/icrai47710.2019.8967385.
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Abbott, Dallas H., Dionne Hutson, Dionne Hutson, Alyssa Marrero, Alyssa Marrero, Karin A. Block, Karin A. Block et al. "REPLICATION OF ANNUAL CYCLES IN MN IN HUDSON RIVER CORES: MN PEAKS DURING HIGH WATER FLOW". In GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-303075.
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Kodochigov, N., Yu Sukharev, E. Marova, N. Ponomarev-Stepnoy, E. Glushkov, P. Fomichenko e C. Ellis. "Possibility of Different Fuel Cycles Usage in GT-MHR". In 10th International Conference on Nuclear Engineering. ASMEDC, 2002. http://dx.doi.org/10.1115/icone10-22404.
Testo completoAbstract (sommario):
The GT-MHR reactor core is characterized by flexibility of neutronic characteristics at the given average power density and fixed geometrical dimensions of reactor core. Such flexibility makes it possible to start the reactor operation with one fuel cycle, and then to turn to another type of core fuel load without changes of main reactor elements: fuel block design, core and reflector size, control rod number etc. Preliminary analysis reindicates the commercial viability of the GT-MHR, part of which is due to the ability to accommodate different fuel types and cycles. This paper presents the results of studies of the neutronic characteristics of reactor cores using different fuel (low- and high-enriched uranium, MOX fuel). Comparison of different fuel cycles is carried out for a three-batch refueling option with respect to following characteristics: discharged fuel burnup, reactivity change during one partial cycle of fuel burnup, consumption of fissile isotopes per unit of produced energy, power distribution, reactivity effects, control rods worth. It is shown, that the considered options of fuel loads provide the three-year fuel campaign (with accounting of capacity factor ∼ 0,8) without change of core design, number and design of control rods at transition from the one fuel type to another.
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Barua, Bipul, Subhasish Mohanty, Saurindranath Majumdar e Krishnamurti Natesan. "Implementation and Validation of a Fully Mechanistic Fatigue Modeling Approach in a High Performance Computing Framework". In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93954.
Testo completoAbstract (sommario):
Abstract Current approaches of fatigue evaluation of nuclear reactor components or other safety critical structural systems use S∼N curve based empirical relations which may have large uncertainty. This uncertainty may be reduced by using a more mechanistic approach. In the proposed mechanistic approach, material models are developed based on the evolution of material behavior under uniaxial fatigue experiments and implement those models into 3D finite element (FE) calculations for fatigue evaluation under multiaxial loading. However, this approach requires simulating structures under thousands of fatigue cycles which necessitates the use of high performance computing (HPC) to determine fatigue life of a large component/system within reasonable time frame. Speeding up the FE simulation of large systems requires the use of a higher number of cores, which is extremely costly, particularly when a commercial FE code is used. Also, commercial software is not necessarily optimized for use in an HPC environment. In this work, an open source parallel computing solver along with a multi-core cluster is used to scale up the number of cores. The HPC-based mechanistic fatigue modeling framework is validated through evaluating fatigue life of a pressurized water reactor surge line pipe under idealistic loading cycles and comparing the simulation results with observations from uniaxial fatigue experiment of 316 stainless steel specimen.
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Drzewiecki, Peter, Whitney Plourde e Randolph P. Steinen. "CORRELATION OF LOWER PORTLAND FORMATION (LOWER JURASSIC) LACUSTRINE CYCLES IN CORES FROM TWO DRILLING PROJECTS IN SOUTH HARTFORD, CONNECTICUT". In 51st Annual Northeastern GSA Section Meeting. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016ne-272151.
Testo completo
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Gupta, M., e G. J. Stewart. "INFLUENCE OF CELL CYCLING ON MAGNITUDE OF RESPONSE OF HUMAN UMBILICAL VEIN ENDOTHELIAL CELLS (EC) TO NOREPINEPHRINE (NE) AND HISTAMINE (H)". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644830.
Testo completoAbstract (sommario):
EC have several roles in preventing thrombosis. Efficiency with which EC fulfill these might well influence outcome of potentially thrombotic stimuli. Thus, factors that influence EC function are of interest. As a general measure of EC response to NE and H the level of cAMP was measured. EC were harvested and passaged by enzymatic digestion and grown in DMEM plus 10% fetal calf serum and antibiotics. cAMP was assayed by radioimmunoassay. Percentage cycling cells was determined by autoradiography of cultures pulse labeled with tritiated thymidine and was increased by hydroxyurea treatment.Basal cAMP was remarkably consistent (less than 10% difference) for cells isolated from different cords, studied after different number of passages, fresh or frozen and with varying percentage of cells cycling. However, magnitude of response to agonists was highly variable. Within the same cell lot between 5-8 passages, magnitude of response was directly proportional to percentage of cycling cells but magnitude ofresponse for different cell lots varied over several fold.EC response to NE was mediated through B-adrenergic receptors and that to H through H receptors. Variability might be caused by differences in receptor number or some intracellular process.
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Silvério, Gabriel André, Isabela Louise Weber, Renata Cristine Alves, Pedro Arthur Possan, Mateus Pinto Marchetti, Vera Cristina Terra, Karen Luiza Ramos Socher, Nancy Watanabe e Carlos Cesar Conrado Caggiano. "Cytotoxic lesion of the corpus callosum associated with Tumor Lysis Syndrome". In XIV Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2023. http://dx.doi.org/10.5327/1516-3180.141s1.538.
Testo completoAbstract (sommario):
Case presentation: MCP, 39 years, female, with primary rectal cancer with lung metastases being treated with weekly cycles of chemotherapy, without other comorbidities. At the end of 46 hours of another cycle of this treatment, patient presented an episode of weakness associated with release of the sphincters, without clonism. Physical examination with stable vital signs, closed eyelids, non-contacting and glasgow coma scale (GCS) 10. Laboratory tests with hypocalcemia, uremia, hyperphosphatemia, increased creatinine, hypomagnesemia, hyperuricemia. On the following day she underwent hemodialysis and evolves with improvement in the level of consciousness (GCS 14), communicative, mild confusion and anterograde amnesia. No alteration at neurological examination. cranioencephalic magnetic resonance imaging with contrast demonstrating signs of diffusion restriction in the splenium region of the corpus callosum. With this, it was possible to determine the diagnosis of cytotoxic lesions of the corpus callosum (CLOCCS) due to tumor lysis syndrome. Discussion: CLOCCs are secondary lesions associated with varied etiologies, including drug therapy, malignancy, metabolic abnormalities (e.g. electrolyte imbalance) and infections. Cell-cytokine interactions lead to massively increased levels of cytokines and extracellular glutamate, resulting in dysfunction of callosal neurons and microglia, and cytotoxic edema develops as water becomes trapped whitin the cells. CLOCCs appears in magnetic resonance imaging as areas of increased signal intensity on FLAIR and low diffusion on diffusion weighted. This lesion is usually midline, reversible and symmetric. Conclusion: It is important to know the radiographic features of CLOCCS and theirs known causes, so the source can be found and addressed and avoid misdiagnosis of primary colossal conditions.
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Yu, Yang, e James J. Sheng. "An Experimental Investigation of the Effect of Pressure Depletion Rate on Oil Recovery from Shale Cores by Cyclic N2 Injection". In Unconventional Resources Technology Conference. Society of Petroleum Engineers, 2015. http://dx.doi.org/10.2118/178494-ms.
Testo completoRapporti di organizzazioni sul tema "Cyclist Corps"
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Meidan, Rina, e Robert Milvae. Regulation of Bovine Corpus Luteum Function. United States Department of Agriculture, marzo 1995. http://dx.doi.org/10.32747/1995.7604935.bard.
Testo completoAbstract (sommario):
The main goal of this research plan was to elucidate regulatory mechanisms controlling the development, function of the bovine corpus luteum (CL). The CL contains two different sterodigenic cell types and therefore it was necessary to obtain pure cell population. A system was developed in which granulosa and theca interna cells, isolated from a preovulatory follicle, acquired characteristics typical of large (LL) and small (SL) luteal cells, respectively, as judged by several biochemical and morphological criteria. Experiments were conducted to determine the effects of granulosa cells removal on subsequent CL function, the results obtained support the concept that granulosa cells make a substaintial contribution to the output of progesterone by the cyclic CL but may have a limited role in determining the functional lifespan of the CL. This experimental model was also used to better understand the contribution of follicular granulosa cells to subsequent luteal SCC mRNA expression. The mitochondrial cytochrome side-chain cleavage enzyme (SCC), which converts cholesterol to pregnenolone, is the first and rate-limiting enzyme of the steroidogenic pathway. Experiments were conducted to characterize the gene expression of P450scc in bovine CL. Levels of P450scc mRNA were higher during mid-luteal phase than in either the early or late luteal phases. PGF 2a injection decreased luteal P450scc mRNA in a time-dependent manner; levels were significantly reduced by 2h after treatment. CLs obtained from heifers on day 8 of the estrous cycle which had granulosa cells removed had a 45% reduction in the levels of mRNA for SCC enzymes as well as a 78% reduction in the numbers of LL cells. To characterize SCC expression in each steroidogenic cell type we utilized pure cell populations. Upon luteinization, LL expressed 2-3 fold higher amounts of both SCC enzymes mRNAs than SL. Moreover, eight days after stimulant removal, LL retained their P4 production capacity, expressed P450scc mRNA and contained this protein. In our attempts to establish the in vitro luteinization model, we had to select the prevulatory and pre-gonadotropin surge follicles. The ratio of estradiol:P4 which is often used was unreliable since P4 levels are high in atretic follicles and also in preovulatory post-gonadotropin follicles. We have therefore examined whether oxytocin (OT) levels in follicular fluids could enhance our ability to correctly and easily define follicular status. Based on E2 and OT concentrations in follicular fluids we could more accurately identify follicles that are preovulatory and post gonadotropin surge. Next we studied OT biosynthesis in granulosa cells, cells which were incubated with forskolin contained stores of the precursor indicating that forskolin (which mimics gonadotropin action) is an effective stimulator of OT biosynthesis and release. While studying in vitro luteinization, we noticed that IGF-I induced effects were not identical to those induced by insulin despite the fact that megadoses of insulin were used. This was the first indication that the cells may secrete IGF binding protein(s) which regonize IGFs and not insulin. In a detailed study involving several techniques, we characterized the species of IGF binding proteins secreted by luteal cells. The effects of exogenous polyunsaturated fatty acids and arachidonic acid on the production of P4 and prostanoids by dispersed bovine luteal cells was examined. The addition of eicosapentaenoic acid and arachidonic acid resulted in a dose-dependent reduction in basal and LH-stimulated biosynthesis of P4 and PGI2 and an increase in production of PGF 2a and 5-HETE production. Indomethacin, an inhibitor of arachidonic acid metabolism via the production of 5-HETE was unaffected. Results of these experiments suggest that the inhibitory effect of arachidonic acid on the biosynthesis of luteal P4 is due to either a direct action of arachidonic acid, or its conversion to 5-HETE via the lipoxgenase pathway of metabolism. The detailed and important information gained by the two labs elucidated the mode of action of factors crucially important to the function of the bovine CL. The data indicate that follicular granulosa cells make a major contribution to numbers of large luteal cells, OT and basal P4 production, as well as the content of cytochrome P450 scc. Granulosa-derived large luteal cells have distinct features: when luteinized, the cell no longer possesses LH receptors, its cAMP response is diminished yet P4 synthesis is sustained. This may imply that maintenance of P4 (even in the absence of a Luteotropic signal) during critical periods such as pregnancy recognition, is dependent on the proper luteinization and function of the large luteal cell.
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Kalaidjian, Ellis, Margaret Kurth, Bari Greenfeld e Matthew Smith. Financing natural infrastructure : the Elizabeth River Project, Chesapeake Bay, VA. Engineer Research and Development Center (U.S.), aprile 2024. http://dx.doi.org/10.21079/11681/48413.
Testo completoAbstract (sommario):
Knowledge gaps surrounding natural infrastructure (NI) life cycles and performance thwart widespread implementation of NI in civil works projects. In particular, information about funding or financing the scoping, design, construction, monitoring, and adaptive management of NI projects constitutes a key need as there is no standard process for securing funds. This technical note is part of a series documenting successful examples of funding NI projects and sharing lessons learned about a variety of funding and financing methods to increase the implementation of NI projects. The research effort is a collaboration between the Engineering With Nature® (EWN®) and Systems Approach to Geomorphic Engineering (SAGE) programs of the US Army Corps of Engineers (USACE). This technical note explores how the Elizabeth River Project (ERP), a nonprofit organization based in Norfolk, Virginia, developed a homeowner cost-sharing program to fund NI projects—living shorelines, rain gardens, and riparian buffers—within an urban watershed.
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Correia, V., R. A. Fensome, R. A. MacRae, L. T. Dafoe e G. L. Williams. Mesozoic event-stratigraphy of the Scotian Margin, offshore Nova Scotia: preliminary palynological results from the Upper Member of the Missisauga Formation in Panuke B-90. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/331910.
Testo completoAbstract (sommario):
Conceived as a continuation of the previous multidisciplinary event stratigraphy studies of the Late Cretaceous to Neogene of the Scotian Margin in the 2000s, the "Mesozoic eventstratigraphy of the Scotian Margin" project proposes a similar study for the Late Triassic to Early Cretaceous interval. The first stage of this project comprises a detailed multidisciplinary study of the composite Lower Cretaceous section from Panuke B-90 and Cohasset A-52 conventional cores. The present work reports initial palynologic data from the formal Upper Member of the Missisauga Formation in Panuke B-90. These data, combined with preliminary insights from sedimentary facies, macrofossil, and trace fossil analyses, suggest that from the base of the studied section upwards involves a transition from a neritic/shelfal to a mainly estuarine-brackish setting. This was followed by a transgressive cycle through the Upper Member of the Missisauga Formation, which culminated in a return of more fully marine environments near the base of the overlying Naskapi Member of the Logan Canyon Formation. It is apparent that this transgression is not continuous, but intercalated with smaller cycles, well documented by the fluctuations in dominance between terrestrial (pollen and spore abundance) versus marine (mainly dinoflagellate-cyst abundance and richness) palynomorph trends through this succession, presented here in three main intervals. The dinoflagellate-cyst assemblages and key bioevents recorded in this initial study indicate a Barremian age for the Upper Member of the Missisauga Formation in Panuke B-90. The overlying Naskapi Member is expected to be of early Aptian age based on previous reports of the presence of the age-diagnostic ammonite Deshayesites sp. Ongoing work on the conventional cores from Panuke B-90, and subsequently Cohasset A-52 and other wells, will contribute to a comprehensive Mesozoic event-stratigraphic framework for the Scotian Margin.
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Sun, S., F. R. Brunton, T. R. Carter, J. R. Clarke, H. A J Russell, K. Yeung, A. Cachunjua e J. Jin. Porosity and permeability variations in the Silurian Lockport Group and A-1 carbonate unit, southwestern Ontario. Natural Resources Canada/CMSS/Information Management, 2023. http://dx.doi.org/10.4095/331902.
Testo completoAbstract (sommario):
This is the first regional porosity/permeability study to incorporate petroleum industry laboratory core analyses submitted to the Ontario government and managed by Ontario's Oil Gas and Salt Resources Library. This study comprises 11,759 analyses for the Early Silurian Lockport Group of southwestern Ontario from 150 drill cores. The Lockport Group consists of a cyclic succession of dolostones and minor limestones comprising, in ascending order: Gasport, Goat Island, Eramosa, and Guelph formations. This stacked carbonate succession was deposited on an eastward-deepening carbonate ramp, extending from Michigan, through southwestern Ontario, to Ohio, Pennsylvania and New York. It is overlain disconformably by restricted marine carbonates, evaporites and mixed shales of the Salina Group, whereas unconformably underlain by one of four formations that include, the Lions Head (a stratigraphic equivalent of part of the Rochester), DeCew, Rochester and Irondequoit. To ensure appropriate stratigraphic assignment of the laboratory test intervals, a quality assurance/quality control review on formational tops was carried out on the 150 cores that were tested. This regional subsurface work resulted in the reassignment of 846 formation tops that were verified by examination of drill core, drill cuttings, and geophysical well data including gamma-ray, neutron and density logs. Core analysis datasets have been validated by summarizing laboratory protocols and standards and reconciling data fields in the core analysis database with auxiliary data, including geophysical logs, thin sections, and core examinaion. This auxiliary data was then used to identify data outliers to update the core analysis database. The measurements of porosity and permeability were then assigned a formation rank plotted on a subregional scale. Average porosity and permeability values have been divided into statistical populations for each formation assigned by three depositional realms. The southwestern Ontario study area has been divided into three paleogeographic settings, based on distinctive lithofacies that correspond to different carbonate depositional regimes and regions of paleokarstification. From northwest to southeast, the lithofacies reflect an inner to outer carbonate ramp setting designated as area 1-3 from northwest to southeast. Area 1 is the inter-pinnacle karst region and includes some of thepinnacle structures within the Lockport Group. This region has the most significant paleokarstification of the upper Lockport Group (Guelph and Goat Island formations) and overlying Salina Group A-unit. Area 2 has rare pinnacle structures, where no porosity/permeability core analyses data are available. Area 3 is the middle to outer portion of the Lockport carbonate ramp, with local development of reef mound phases in the lower Goat Island and Gasport formations. The porosity and permeability variability corresponds with areal distribution of paleokarstification and resulting diagenetic phases in Area 1, and lithofacies variations and temporal/spatial history of karstification in Area 3. Higher porosity and permeability generally coincide with greater thicknesses of the oil and gas reservoir within pinnacles in Area 1 and reef mound phases of Lockport Group and lower Salina Group A-1 Carbonate in Area 3. Within inter-pinnacle karst regions in Area 1, average porosity for each formation is consistently high with little variations. In Area 3, a general increase of porosity and permeability towards the southeast corresponds with lithofacies ranging from restricted lagoonal/platform interior deposits to carbonate bank deposits with local development of reef mound phases in the Gasport and Goat Island formations. There has been significant erosion and karstification within and at the tops of these pinnacles, resulting in higher porosity and permeability of the Guelph and upper Goat Island formations, and the overlying Salina Group A-1 unit. Paleokarstic events have enhanced various porosity types, including intercrystalline, moldic, irregular and fenestral vugs, and cavities.
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Swanson, David. Tree investigations in the Noatak National Preserve, Alaska, 2011?2022: Old-growth and new forests. National Park Service, 2023. http://dx.doi.org/10.36967/2301700.
Testo completoAbstract (sommario):
Tree rings in the Noatak National Preserve provide information about the growth of trees at the cold limit of tree survival in northwestern North America. The present study was based on cores and other tree measurements (tree basal area, height, and number per unit area) of white spruce (Picea glauca) and balsam poplar (Populus balsamifera) trees taken from 39 permanent monitoring plots (34 with coreable trees) at three locations in the Preserve. The tree rings widths were measured and then normalized using a 50-year smoothing spline to remove the effects of growth variations through the life cycles of the trees. Old-growth white spruce forests, which here include numerous trees over 200 years old and some that are more than 300 years old, form open stands on well-drained slopes. Stands of younger trees that became established in the 1900s are present near elevational tree-line, and in small groves on tussock tundra. These younger stands are interpreted primarily as the result of forest expansion due to climate warming, though re-establishment of trees after wildfire is also possible in the tussock tundra. On river floodplains and terraces, stands of both white spruce and balsam poplar were also initiated in the 1900s, but here the youth of the trees is probably due to colonization of new areas exposed by river channel migration. Both the old-growth and younger forests showed continuing growth (as expressed by an increase in stand basal area) between our initial visit in 2011 and re-visit in 2021 or 2022, with the greatest increases occurring on floodplains. Tree rings showed much year-to-year variation in width, but the effect of individual cold summers was surprisingly weak. Some of the major global climate perturbations due to volcanic eruptions were visible in the tree ring record, but the resulting ring growth was generally no worse than other bad growth years within a few decades of the volcanic event. Tree ring width was statistically correlated more closely with the average warmth of several preceding growing seasons (as expressed by the annual sum of thaw degree-days) than with the current year?s or the previous year?s warmth alone. This is probably due to the cumulative effect of several years? warmth (or cold) on the conditions in the tree rooting zone, on the amount of foliage available for photosynthesis, and the level of stored reserves in the tree.