26 research outputs found
L'inconstitutionnalité des pouvoirs du protonotaire spécial
The office of special prothonotary was created in 1975 by an amendment to the Code of Civil Procedure. The main purpose of the change was to ease the administration of justice before the courts. For this reason, the special prothonotary received many assignments which were reserved until then to a judge sitting in chambers and even to the court itself. Such transfer of duties and powers may conflict with section 96 of the BNA Act, which acts as a bar to prevent the withdrawal of judicial functions from a superior, county or district court. This paper deals with the interferences between various sections of the Code of Civil Procedure and section 96 of the BNA Act. The first part of the paper deals with the approach adopted by the courts. The true test, according to the case-law, is to determine the nature of the function involved. Since only judicial functions are protected by section 96, it is intravires the Legislature of Quebec to confer on a board or tribunal administrative or ministerial powers. If the transfer involves judicial functions, the courts will use the test adopted by the Privy Council in Labour Relations Board of Saskatchewan v. John East Iron Works and by Sir Lyman Duff in In re Adoption Act, and examine whether the transferee is analogous to a superior, district or county court. The courts will also have to apply the « 1867 statute books test » : was the particular function conferred to the prothonotary before 1867 ? If the results of each of the two tests are affirmative, then the function is one protected by section 96 of the BNA Act and its transfer is ultra vires the provincial Legislature. If the results are negative, the courts will examine if the provisions involved have the effect of vesting in the special prothonotary the powers of a superior court judge. If the courts conclude that it is so, then, the assignment is ultra vires the powers of the provincial Legislature. The second part deals with each of the assignments transferred to the special prothonotary. These are threefold in nature: 1. Actions by default to appear or by default to plead under article 195 C.C.P. ; 2. Jurisdiction under article 44.1(1) C.C.P. ; 3. Interlocutory or incidental proceedings, contested or not, but, if so, with the consent of the parties. The paper concludes that most of the provisions dealing with the duties and powers of the special prothonotary are unconstitutiona
Quantifying bamboo coral growth rate nonlinearity with the radiocarbon bomb spike : a new model for paleoceanographic chronology development
© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 125 (2017): 26-39, doi:10.1016/j.dsr.2017.04.006.Bamboo corals, long-lived cold water gorgonin octocorals, offer unique paleoceanographic archives of the
intermediate ocean. These Isididae corals are characterized by alternating gorgonin nodes and high Mg-calcite
internodes, which synchronously extend radially. Bamboo coral calcite internodes have been utilized to obtain
geochemical proxy data, however, growth rate uncertainty has made it difficult to construct precise
chronologies for these corals. Previous studies have relied upon a tie point from records of the anthropogenic
Δ14C bomb spike preserved in the gorgonin nodes of live-collected corals to calculate a mean radial extension
rate for the outer ~50 years of skeletal growth. Bamboo coral chronologies are typically constructed by
applying this mean extension rate to the entire coral record, assuming constant radial extension with coral age.
In this study, we aim to test this underlying assumption by analyzing the organic nodes of six California margin
bamboo corals at high enough resolution (<0.5 mm) to identify the Δ14C bomb spike, including two tie points
at 1957 and 1970, plus coral collection date (2007.5) for four samples. Radial extension rates between tie points
ranged from 10 to 204 ÎĽm/year, with a decrease in growth rate evident between the 1957-1970 and 1970-
2007.5 periods for all four corals. A negative correlation between growth rate and coral radius (r = -0.7; p =
0.03) was determined for multiple bamboo coral taxa and individuals from the California margin,
demonstrating a decline in radial extension rate with specimen age and size. To provide a mechanistic basis for
these observations, a simple mathematical model was developed based on the assumption of a constant
increase in circular cross sectional area with time to quantify this decline in radial extension rate with coral size
between chronological tie points. Applying the area-based model to our Δ14C bomb spike time series from
individual corals improves chronology accuracy for all live-collected corals with complete Δ14C bomb spikes.
Hence, this study provides paleoceanographers utilizing bamboo corals with a method for reducing age model
uncertainty within the anthropogenic bomb spike era (~1957-present). Chronological uncertainty is larger for
the earliest portion of coral growth, particularly for skeleton precipitated prior to bomb spike tie points,
meaning age estimations for samples living before 1957 remain uncertain. Combining this technique with
additional chronological markers could improve age models for an entire bamboo coral. Finally, the relative
consistency in growth rate in similarly-aged corals of the same depth and location supports the hypothesis that
skeletal growth may be limited by local environmental conditions.This research was made possible
by National Science Foundation Award #1420984 to M. LaVigne and a Clare Boothe Luce Fellowship to M.
Frenkel
Reproducibility of Ba/Ca variations recorded by northeast Pacific bamboo corals
Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 32 (2017): 966–979, doi:10.1002/2017PA003178.Trace elemental ratios preserved in the calcitic skeleton of bamboo corals have been shown to serve as archives of past ocean conditions. The concentration of dissolved barium (BaSW), a bioactive nutrientlike element, is linked to biogeochemical processes such as the cycling and export of nutrients. Recent work has calibrated bamboo coral Ba/Ca, a new BaSW proxy, using corals spanning the oxygen minimum zone beneath the California Current System. However, it was previously unclear whether Ba/Cacoral records were internally reproducible. Here we investigate the accuracy of using laser ablation inductively coupled plasma mass spectrometry for Ba/Cacoral analyses and test the internal reproducibility of Ba/Ca among replicate radial transects in the calcite of nine bamboo corals collected from the Gulf of Alaska (643–720 m) and the California margin (870–2054 m). Data from replicate Ba/Ca transects were aligned using visible growth bands to account for nonconcentric growth; smoothed data were reproducible within ~4% for eight corals (n = 3 radii/coral). This intracoral reproducibility further validates using bamboo coral Ba/Ca for BaSW reconstructions. Sections of the Ba/Ca records that were potentially influenced by noncarbonate bound Ba phases occurred in regions where elevated Mg/Ca or Pb/Ca and coincided with anomalous regions on photomicrographs. After removing these regions of the records, increased Ba/Cacoral variability was evident in corals between ~800 and 1500 m. These findings support additional proxy validation to understand BaSW variability on interannual timescales, which could lead to new insights into deep sea biogeochemistry over the past several centuries.NSF Grant Number: OCE-1420984;
NOAA/OE Grant Number: NA16RP2637;
MIT-WHOI Joint Program;
American Geophysical Union Travel Grant;
UC Davis President's Undergraduate Fellowship;
Bowdoin College Gibbons Summer Research Fellowship2018-03-1
Staphylococcus aureus infective endocarditis versus bacteremia strains: Subtle genetic differences at stake
AbstractInfective endocarditis (IE)(1) is a severe condition complicating 10–25% of Staphylococcus aureus bacteremia. Although host-related IE risk factors have been identified, the involvement of bacterial features in IE complication is still unclear. We characterized strictly defined IE and bacteremia isolates and searched for discriminant features. S. aureus isolates causing community-acquired, definite native-valve IE (n=72) and bacteremia (n=54) were collected prospectively as part of a French multicenter cohort. Phenotypic traits previously reported or hypothesized to be involved in staphylococcal IE pathogenesis were tested. In parallel, the genotypic profiles of all isolates, obtained by microarray, were analyzed by discriminant analysis of principal components (DAPC)(2). No significant difference was observed between IE and bacteremia strains, regarding either phenotypic or genotypic univariate analyses. However, the multivariate statistical tool DAPC, applied on microarray data, segregated IE and bacteremia isolates: IE isolates were correctly reassigned as such in 80.6% of the cases (C-statistic 0.83, P<0.001). The performance of this model was confirmed with an independent French collection IE and bacteremia isolates (78.8% reassignment, C-statistic 0.65, P<0.01). Finally, a simple linear discriminant function based on a subset of 8 genetic markers retained valuable performance both in study collection (86.1%, P<0.001) and in the independent validation collection (81.8%, P<0.01). We here show that community-acquired IE and bacteremia S. aureus isolates are genetically distinct based on subtle combinations of genetic markers. This finding provides the proof of concept that bacterial characteristics may contribute to the occurrence of IE in patients with S. aureus bacteremia
Coralline P/CA: development and application of a novel surface ocean phosphate proxy
The supply of limiting nutrients to the low latitude ocean is controlled by physical processes linked to climate variations, but methods for reconstructing past nutrient concentrations in the surface ocean are few and indirect. This thesis presents the first calibration and downcore application of a new surface ocean phosphate (PO4 SW) proxy derived from coral skeleton P/Ca ratios. Skeletal P/Ca cycles tracked variations in past PO4 SW synchronously with temperature variations associated with seasonal upwelling in a 4-year Gulf of Panamá Pavona gigantea coral. P/Ca records in co-located Gulf of Panamá Pavona gigantea and Porites lobata colonies were strongly correlated to a contemporaneous time-series record of PO4 SW, supporting application of multi-colony calibration equations to down-core records. The P/Ca proxy was applied downcore to reconstruct an 18-year history of central equatorial Pacific PO4 SW. The PO4 SW record decreased during El Niño warm phases, resulting from decreased upwelling. In addition, a large 6-fold decrease in PO4 SW occurred from ~1982-1990, distinct from sea surface temperature changes in the central Equatorial Pacific. The decadal scale nutrient regime shift likely occurred in response to the observed decreases in wind stress and equatorial upwelling with possible linkages to the 1976/77 climate shift and changes in mid-latitude upwelling source water. The reliability of P/Ca was tested in low nutrient environments (Gulf of Eilat, Israel and Florida Keys, USA). Downcore P/Ca variability is low on centennial timescales in the Florida Keys record, implying that other possible influences on P incorporation (i.e. biological vital effects) are minimal and that the P/Ca proxy is not subject to major diagenetic alteration. With further development, the coralline P/Ca proxy could be applied to reconstruct PO4 SW on millennial timescales and be used to place modern tropical and subtropical nutrient distributions and dynamics in a paleoceanographic perspective.Ph.D.Includes abstractVitaIncludes bibliographical referencesby Michèle Gloria LaVign
Multi-colony calibrations of coral Ba/Ca with a contemporaneous in situ seawater barium record
The coral skeleton barium to calcium ratio (Ba/Ca ), a proxy for seawater barium concentrations (Ba ), has been interpreted as a tracer of upwelling based on the characteristic nutrient like depth profile of Ba . However, in some tropical regions, such as the Gulf of Panamá, substantial influence of terrestrial runoff inputs and differences between the vertical distribution of Ba and that of the major nutrients (nitrate and phosphate) in the upper water column can complicate the interpretation of Ba/Ca as an upwelled nutrient proxy. In the Gulf of Panamá, contemporaneous Ba/Ca records from multiple colonies of Porites lobata, Pavona gigantea, and Pavona clavus corals record a nearly twofold change in surface water Ba as a 20-70% increase in skeletal Ba/Ca with excellent correlation among Ba/Ca records from co-located colonies (r = 0.86-0.99). These results provide, for the first time, an absolute calibration of the coral Ba proxy with a contemporaneous Ba record. Compiling the Ba/Ca records from three co-located colonies of each species into taxon-specific composite regressions reveals strong statistically significant correlations with the Ba time-series record (p \u3c 0.001). Differences among taxa in regression slope, y-intercept, and average distribution coefficient, as well as a demonstration of the application of the P. clavus calibration to a previously published Ba/Ca record, emphasize the necessity of using taxon-specific calibrations to reconstruct changes in Ba with accuracy. These results support the application of Ba/Ca to reconstruct past changes in absolute Ba concentrations, adding an important tool to the collection of geochemical proxies for reconstructing surface ocean biogeochemical processes in the past. coral SW SW SW coral coral SW SW coral SW coral SW coral S
Skeletal P/Ca tracks upwelling in Gulf of Panama coral: Evidence for a new seawater phosphate proxy
The supply of limiting nutrients to the low latitude ocean is controlled by physical processes linked to climate variations, but methods for reconstructing past nutrient concentrations in the surface ocean are few and indirect. Here, we present laser ablation mass spectrometry results that reveal annual cycles of P/Ca in a 4-year record from the scleractinian coral Pavona gigantea (mean P/Ca = 118 mmol mol?1). The P/Ca cycles track variations in past seawater phosphate concentration synchronously with skeletal Sr/Ca-derived temperature variations associated with seasonal upwelling in the Gulf of Panama´. Skeletal P/Ca varies seasonally by 2–3 fold, reflecting the timing and magnitude of dissolved phosphate variations. Solution cleaning experiments on drilled coral powders show that over 60% of skeletal P occurs in intracrystalline organic phases. Coral skeleton P/Ca holds promise as a proxy record of nutrient availability on time scales of decades to millennia