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Several Episodes (several + episode)
Selected AbstractsBehavioral effects of introducing pied tamarin (Saguinus bicolor) to black howler monkey (Alouatta caraya) and white-faced saki (Pithecia pithecia) in a zoological parkAMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2008Lydia Gentry Abstract Mixed-species primate exhibits are becoming more common in zoological parks as a means to display a diverse array of animals both more naturalistically and with more economy of space. Here, we describe behavioral changes during the introduction process of a pair of pied tamarins (Saguinus bicolor) to an established group of black howler monkeys (Allouatta caraya) and white-faced saki monkeys (Pithecia pithecia). Data were collected during six phases, representing introductions among the various species and to exhibit space and off-exhibit holding. The pied tamarins were consistently the most active of the three species. Although activity levels of the howler and saki monkeys remained constant throughout, that of the tamarins declined as the introduction progressed. Several episodes of aggression between the tamarins and the sakis were observed, but did not coincide with patterns predicted by previous intra-specific introductions. The three-species mix remained stable for several months; however, escalating aggression ultimately led to the removal of the sakis from the mixed-species exhibit. Despite our mixed results, we contend that only through continued trials, coupled with careful and systematic monitoring, can we ultimately identify stable mixes of species. Am. J. Primatol. 70:505,509, 2008. © 2008 Wiley-Liss, Inc. [source] An intranuclear bacilliform virus associated with near extirpation of Austropotamobius pallipes Lereboullet from the Nant watershed in Ardéche, FranceJOURNAL OF FISH DISEASES, Issue 9 2002B F Edgerton White-clawed crayfish, Austropotamobius pallipes, were endemic to the Nant watershed, Ardéche, France, until they were extirpated by epizootic mortality at the beginning of the twentieth century. A. pallipes were successfully reintroduced to the Nant watershed in the middle of the twentieth century. However, epizootic mortality was observed in the Nant watershed in the summer of 2000 during which time A. pallipes was extirpated from downstream regions. Dead and moribund crayfish were again detected in several episodes in summer 2001 and by October the range of A. pallipes was reduced to the headwaters of just one of the three streams in the watershed. Water quality for the watershed in summer 2001 was appropriate for crayfish habitation. Bacteriology and mycology on A. pallipes collected during several of the mortality episodes in 2001 failed to reveal a cause. However, histopathology revealed a high occurrence of intranuclear eosinophilic inclusions in hepatopancreatocytes of A. pallipes. The nuclei were hypertrophic and contained bacilliform virions consisting of a cylindrical nucleocapsid surrounded by a trilaminar envelope. Virions in section were approximately 63 × 258 nm and nucleocapsids were approximately 52 × 225 nm. It is unclear whether the intranuclear bacilliform virus was the cause of the mortality episodes or was a contributor to a disease complex involving one or several other undetected pathogens. [source] Living on the edge: demographic and phylogeographical patterns in the woodlouse-hunter spider Dysdera lancerotensis Simon, 1907 on the eastern volcanic ridge of the Canary IslandsMOLECULAR ECOLOGY, Issue 15 2007LETICIA BIDEGARAY-BATISTA Abstract The Eastern Canary Islands are the emerged tips of a continuous volcanic ridge running parallel to the northeastern African coast, originated by episodic volcanic eruptions that can be traced back to the Miocene and that, following a major period of quiescence and erosion, continued from the Pliocene to the present day. The islands have been periodically connected by eustatic sea-level changes resulting from Pleistocene glacial cycles. The ground-dwelling spider Dysdera lancerotensis Simon, 1907 occurs along the entire ridge, except on recent barren lavas and sand dunes, and is therefore an ideal model for studying the effect of episodic geological processes on terrestrial organisms. Nested clade and population genetic analyses using 39 haplotypes from 605 base pairs of mitochondrial DNA cytochrome c oxidase I sequence data, along with phylogenetic analyses including two additional mitochondrial genes, uncover complex phylogeographical and demographic patterns. Our results indicate that D. lancerotensis colonized the ridge from north to south, in contrast to what had been expected given the SSW-NNE trend of volcanism and to what had been reported for other terrestrial arthropods. The occurrence of several episodes of extinction, recolonization and expansion are hypothesized for this species, and areas that act as refugia during volcanic cycles are identified. Relaxed molecular clock methods reveal divergence times between main haplotype lineages that suggest an older origin of the northern islets than anticipated based on geological evidence. This study supports the key role of volcanism in shaping the distribution of terrestrial organisms on oceanic islands and generates phylogeographical predictions that warrant further research into other terrestrial endemisms of this fascinating region. [source] Mitochondrial gene diversity in the common vole Microtus arvalis shaped by historical divergence and local adaptationsMOLECULAR ECOLOGY, Issue 11 2004SABINE FINK Abstract The phylogeography of the common vole (Microtus arvalis) was examined by analysing mitochondrial DNA (mtDNA) sequence variation in 1044 base pairs (bp) of the cytochrome b (cytb) gene and in 322 bp of the control region (ctr) among 106 individuals from 58 locations. The geographical distribution of four previously recognized cytb evolutionary lineages in Europe was refined and a new lineage was found in southern Germany. All lineages were distributed allopatrically, except in one sample that was probably located in a contact zone. The occurrence of several lineages in the Alps is in keeping with their recent recolonization from distinct sources. The translation of 84 cytb DNA sequences produced 33 distinct proteins with relationships that differed from those of the DNA haplotypes, suggesting that the mtDNA lineages did not diverge in response to selection. In comparison with M. agrestis, a neutrality test detected no overall evidence for selection in the cytb gene, but a closer examination of a structural model showed that evolutionarily conserved and functionally important positions were often affected. A new phylogeographical test of random accumulation of nonsynonymous mutations generated significant results in three lineages. We therefore conclude that the molecular diversity of cytb in M. arvalis is overall the result of the demographic history of the populations, but that there have been several episodes of local adaptation to peculiar environments. [source] Stepwise Transition of 2:1 Atrio-Ventricular Block to 1:1 Conduction Induced by Ventricular Premature Beats in a Patient with Atypical AVNRTPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2010ANTONIO SORGENTE M.D. A 55-year-old man with a 2-year history of recurrent paroxysmal palpitations and with an electrocardiogram documentation of atypical atrioventricular nodal re-entrant tachycardia (AVNRT) was referred to us for catheter ablation. After an initial ablation attempt, several episodes of atypical AVNRT were induced. During one of these episodes, we documented a stepwise transition of 2:1 atrioventricular block to 1:1 conduction, following two single ventricular premature beats. This phenomenon confirmed the functional nature of the AV block during AVNRT and indirectly its infra-nodal location. (PACE 2010; 33:e20,e23) [source] CIRCULATION OF PRIVATE NOTES DURING A CURRENCY SHORTAGE,THE MANCHESTER SCHOOL, Issue 4 2009XAVIER CUADRAS-MORATÓ In this paper we present a version of the search theoretical model of money that captures two phenomena that have characterized several episodes of monetary history: currency shortages and the circulation of privately issued notes. As usual in these models, the media of exchange are determined as part of the equilibrium. We characterize all the different equilibria and specify the conditions under which there is a currency shortage and/or privately issued notes are used as means of payment. There always exists an equilibrium in which notes circulate, either alone or together with coins and, hence, credit is a self-fulfilling phenomenon. [source] Observations of downslope winds and rotors in the Falkland IslandsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 605 2005S. D. Mobbs Abstract A field campaign aimed at observing the near-surface flow field across and downwind of a mountain range on the Falkland Islands, South Atlantic, is described. The objective was to understand and eventually predict orographically generated turbulence. The instrumentation was based primarily on an array of automatic weather stations (AWSs), which recorded 30 s mean surface pressure, wind speed and direction (at 2 m), temperature and relative humidity for approximately one year. These measurements were supported by twice-daily radiosonde releases. The densest part of the AWS array was located to the south of the Wickham mountain range, across Mount Pleasant Airfield (MPA). In northerly flow the array provides a detailed study of the flow downwind of the mountain range. The dataset contains several episodes in which the flow downwind of the mountains is accelerated relative to the upwind flow. During some of these episodes short-lived (typically ,1 hour) periods of unsteady flow separation are observed and these are associated with the formation of rotors aloft. Such events present a significant hazard to aviation at MPA. Examination of radiosonde profiles suggests that the presence of a strong temperature inversion at a height similar to the mountain height is a necessary condition for both downwind acceleration and the formation of rotors. The data are used to show that the downwind fractional speed-up is proportional to the non-dimensional mountain height (based on upstream near-surface winds and a depth-averaged Brunt,Väisälä frequency diagnosed from radiosonde data). Similarly, a relationship is established between a quantity that describes the spatial variability of the flow downwind of the mountains and the upstream wind and depth-averaged Brunt,Väisälä frequency. The dependence of the flow behaviour on the Froude number (defined in the usual way for two-layer shallow-water flow) and ratio of mountain height to inversion height is presented in terms of a flow regime diagram. © Royal Meteorological Society, 2005. S. B. Vosper's and P. F. Sheridan's contributions are Crown copyright [source] Autonomic Nervous System Modulation before the Onset of Sustained Atrioventricular Nodal Reentry TachycardiaANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010Gerardo Nigro M.D., Ph.D. Introduction: Our study was designed to analyze dynamic changes in autonomic tone before the onset of typical sustained atrioventricular nodal reentry tachycardia (AVNRT) in a large group of patients without structural heart disease. Materials and Methods: Twenty-four-hour Holter tapes from 42 consecutive patients (27 men and 15 women; aged 30 ± 21 years) with several episodes of sustained typical AVNRT were analyzed. The diagnosis was validated by transesophageal electrophysiological study. The time-domain calculated parameters were SDNN, SDANN, rMSSD, pNN50; the frequency-domain parameters were low-frequency power (LF, 0.04,0.15 Hz), high-frequency power (HF, 0.15,0.40 Hz), very low-frequency power (VLF, 0.008 to 0.04 Hz) and LF/HF. The mean values in the hour before the onset of sustained AVNRT were compared with the mean values of 2 hours before and 1 hour after the onset of sustained AVNRT. Results: The mean SDNN, rMSSD, pNN50, HF were significantly decreased during the hour preceding the onset of AVNRT, when compared to the mean values observed during the time periods selected. Instead, the LF values and LF/HF were increased before the onset of sustained AVNRT. No significant change in the VLF and atrial ectopic beats were observed. Conclusion: This study suggests that sustained typical AVNRT episodes are preceded by increase in adrenergic drive. Ann Noninvasive Electrocardiol 2010;15(1):49,55 [source] Manganese Black Pigments in Prehistoric Paintings: the Case of the Black Frieze of Pech Merle (France)ARCHAEOMETRY, Issue 2 2001B. Guineau Different black pigments of natural origin (mineral or organic) have been examined by means of several analytical methods (colour measurements, elemental analysis and structural analysis). The results, after being compared with each other, then served as reference points in the study of the ,Black Frieze' of the cave of Pech Merle (Lot). After that, colour measurement was investigated in situ on the paintings as a means of displaying small differences (in hue or chroma) between the black colours. The aim of this study was to verify several hypotheses concerning the techniques used by the painters of Pech Merle, and specifically by the one(s) of the Black Frieze. A first objective was that of identifying the nature and, if possible, the origin of the black pigments used in these figures. A second objective was that of determining in which parts of the frieze one or the other (or one and the other) had been used; and the final objective was to provide new technical information that might help us better to understand how the Pech Merle frieze was produced, whether by a single painter and in one episode, for the most part, or, on the contrary, in several episodes and by a succession of different painters. [source] Syncope associated with hypertrophic cardiomyopathy in a dromedary camelAUSTRALIAN VETERINARY JOURNAL, Issue 8 2000C GUTIERREZ A case of hypertrophic cardiomyopathy in a dromedary camel (Camelus dromedarius) is described for the first time. The patient, a castrated 9-year-old animal, presented with a 6-month history of several episodes of syncope after moderate exercise and later at rest. The syncope had a sudden onset and a duration of 30 to 45 seconds. After clinical, electro-cardiographical and echocardiographical examination, a tentative diagnosis of hypertrophic cardiomyopathy was made. At necropsy, the heart had a globose shape and was firm on palpation. The left ventricular free wall and the inter-ventricular septum were thickened in cross-section and the left ventricular lumen was small. The clinical diagnosis was confirmed by histologic examination of heart tissue that demonstrated hypertrophy of myocardial fibres with vesicular nuclei and the presence of diffuse interstitial fibrosis. [source] Posner-Schlossman syndrome (glaucomatocyclitic crisis)CLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 1 2007Ralph J Green DipAppSc(Optom) Posner-Schlossman syndrome (PSS) or glaucomatocyclitic crisis is a rare, typically unilateral recurrent inflammatory ocular hypertensive disease in which diagnosis can be challenging. An acute elevation of intraocular pressure is accompanied by or followed within a few days by a mild, often symptomless uveal inflammation. The mild nature of the uveitis at presentation of the first attack may go undetected. Medical treatment is indicated to prevent pressure-related optic nerve damage and to reduce inflammation. This report details a patient with Posner-Schlossman syndrome whose unilateral pressure elevation was initially treated as acute angle-closure glaucoma. He subsequently had several episodes of increased pressure over a two-year period. Diagnostic difficulties in this case are discussed. [source] | ||||||||||||||||