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Tracing indicator minerals and geochemical pathfinders in glacial sediments back to their up-ice source is a common mineral exploration approach in prospective, formerly glaciated regions. In this study, we utilize surface and subsurface data from the Lac de Gras area of the Northwest Territories to develop a three-dimensional understanding of till compositional anomalies emanating from two known kimberlite pipes, DO-18 and DO-27. Specifically, this study examines the three-dimensional shape of dispersal trains as defined by geochemical pathfinder elements and kimberlite indicator minerals shed from a pair of kimberlite pipes within a till cover of variable thickness. From our ninety-four reverse circulation boreholes (n = 251 till samples), and other publicly-available geologic datasets, we have reconstructed bedrock topography, till thickness, and the subsurface geometry of two dispersal trains. Utilizing our three-dimensional dataset, we have documented the role of basal topography in creating dispersal patterns with contrasting geometries from two adjacent kimberlites, as well as in the preferential preservation of older till units. The combination of field observations of ice-flow indicators and till compositional data demonstrates that features produced by multiple ice flows are preserved in both the erosional and depositional records in this region. Three-dimensional dispersion patterns of kimberlite indicators reflect the effect of shifting ice-flow direction with respect to slope aspect of bedrock topography in governing compositional variability within glacial drift. Our findings suggest that surficial data do not capture the full extent of dispersion patterns even in areas of relatively thin and discontinuous till cover.

Neuropeptides are often co-expressed in neurons but their neurophysiological effects are commonly studied individually. Multiple neuropeptides may therefore be simultaneously released to coordinate proper neural circuit function. Here, we triggered the release of endogenous neuropeptides in brain slices from male mice to better understand the modulation of central amygdala (CeA) inhibitory inputs onto oval (ov) BNST neurons. We found that locally-released neurotensin (NT) and dynorphin (Dyn) antagonistically regulated CeA inhibitory inputs onto ovBNST neurons. NT and Dyn respectively increased and decreased CeA-to-ovBNST inhibitory inputs through NT receptor 1 (NTR1) and kappa opioid receptor (KOR). Additionally, NT and Dyn mRNAs were highly co-localized in ovBNST neurons suggesting that they may be released from the same cells. Together, we showed that NT and Dyn are key modulators of CeA inputs to ovBNST, paving the way to determine whether different conditions or states can alter the neuropeptidergic regulation of this particular brain circuit.

Sulfahydantoin-based molecules may provide a means to counteract antibiotic resistance, which is on the rise. These molecules may act as inhibitors of β-lactamase enzymes, which are key in some resistance mechanisms. In this paper, we report on the synthesis of 6 novel sulfahydantoin derivatives by the key reaction of chlorosulfonyl isocyanate to form α-amino acid derived sulfamides, and their cyclization into sulfahydantoins. The synthesis is rapid and provides the target compounds in 8 steps. We investigated their potential as β-lactamase inhibitors using two common Class A β-lactamases, TEM-1 and the prevalent extended-spectrum TEM-15. Two compounds, 3 and 6, show substantial inhibition of the β-lactamases with IC50 values between 130 and 510 μM and inferred Ki values between 32 and 55 μM.

Fjords can transition from marine embayments to lacustrine waterbodies under glacio-isostatic change following their deglaciation. However, little is known on how a transition from fjord to lake is influenced by glacial dynamics and how it influences sedimentation in and around the basin. Here, we analyse swath bathymetry imagery and subbottom profiles pri in Lake Mekinac (southern Quebec) as well as glacial landforms from LiDAR imagery around the lake to document the evolution of a fjord basin into a lacustrine body during the transition from the Late Pleistocene to the Holocene. These analyses helped refine local glacial history and show that the study area was probably under the up-ice reach of the St. Lawrence Ice Stream during full glacial conditions. The mapping of moraines in and around Lake Mekinac shows that deglaciation of the study area was marked by stabilization of the ice-margin during the Mars-Batiscan Event, which is traditionally correlated to the climate deterioration at the end of the Younger Dryas. The architecture of acoustic facies in the lake indicates a transition from glacial conditions (U1), to proglacial-paraglacial (U2) and to postglacial conditions (U3). The bottom of Lake Mekinac also contains multiple mass movement deposits related to progradation of the Du-Milieu River delta and probably to late-Holocene earthquakes. The acoustic architecture of sediments within the lake indicates that the sedimentation regime was most dependant on the sediment input regime and that the transition from fjord to lake did not significantly influence sedimentation during deglaciation of the watershed. Further work on dating the mass movement deposits that characterise the sediment architecture should provide a better assessment of natural hazard associated with seismological events.

Disturbed lacustrine deposits of eastern Canada have been associated with past seismic events in the intraplate Western Quebec Seismic Zone (WQZ) and the Charlevoix–Kamouraska Seismic Zone (CKSZ). With five major earthquakes that occurred during historical times and hundreds of minor earthquakes, the CKSZ is the most active seismic zone in eastern Canada. Here we present new high-resolution multibeam bathymetric, subbottom profiler and sediment core data collected in Lake Temiscouata, southeastern Quebec, the largest lake located within the influence of the CKSZ. The occurrence of mass-movements in the highly cohesive glaciolacustrine deposits of the lake produced a peculiar lacustrine landscape consisting of steep slide scars and residual mounds and very narrow residual crests. Our data indicate that postglacial times were marked by recurrent seismically-induced mass-movement events that cannot be individually identified in the sedimentary record due to the highly disturbed stratigraphy of the lake and to the absence of significant postglacial background sediments between events. The most recent recorded mass-movement is a distinct debris flow sediment layer on the lake floor that was deposited at ~ 1300 cal BP, very shortly after a distinct large-scale mass-movement event observed across the entire lake basin. The presence of silt layers in gyttja overlying these disturbed units suggests that the region was affected by other seismic events following this event, although no MMDs could be directly related to these layers.

We aimed to determine if state of bladder fullness affects pelvic floor muscle activation in healthy women without urogenital symptoms.Twenty-three nulliparous, continent female participants were recruited to participate. Women were randomized to begin the protocol with either an empty (EF) or a full (FE) bladder. Tonic and maximal voluntary pelvic floor muscle electromyographic activity were measured in three states of bladder fullness (empty, full and uncomfortably full). Electromyographic signal amplitudes were compared among bladder states using separate two-way repeated-measures analyses of variance including bladder state and test order as main effects as well as the interaction between bladder state and test order.Tonic activity of the pelvic floor muscles was significantly higher in the full and uncomfortably full bladder states compared to when the bladder was empty (p0.005). Maximum voluntary electromyographic activation was unaffected by state of bladder fullness (p=0.713).Consistent with studies in which the bladder was filled through saline infusion, these results suggest that tonic activity of the PFMs is higher when the bladder is full compared to when it is empty. However once the bladder is moderately full, tonic PFM activity does not increase with increases in bladder volume.

The Pingualuit Crater, located in the Ungava Peninsula (northern Quebec, Canada) is a 1.4-Ma-old impact crater hosting a ~ 245-m-deep lake. The lake has a great potential to preserve unique paleoclimatic and paleoecological sedimentary records of the last glacial/interglacial cycles in the terrestrial Canadian Arctic. In order to investigate the stratigraphy in the lake and the late Quaternary glacial history of the Pingualuit Crater, this study compiles data from three expeditions carried out in May 2007 (~ 9-m-long sediment core), in August 2010 (~ 50 km of seismic lines), and in September 2012 (high-resolution terrestrial LiDAR topography of the inner slopes). Despite the weak penetration (~ 10 m) of the 3.5-kHz subbottom profiling caused by the presence of boulders in the sedimentary column, seismic data coupled with the stratigraphy established from the sediment core enabled the identification of two glaciolacustrine units deposited during the final stages of the Laurentide Ice Sheet (LIS) retreat in the crater. Two episodes of postglacial mass wasting events were also identified on the slopes and in the deep basin of the crater. The high-resolution topography of the internal slopes of the crater generated from the LiDAR data permitted the confirmation of a paleolake level at 545 m and determination of the elevation of drainage outlets. Together with the mapping of glacial and deglacial landforms from air photographs, the LiDAR data allowed the development of a new deglaciation and drainage scenario for the Pingualuit Crater Lake and surrounding area. The model proposes three main phases of lake drainage, based on the activation of seven outlets following the retreat of the LIS front toward the southwest. Finally, as opposed to other high-latitude crater lake basins such as Lake El'gygytgyn or Laguna Potrok Aike where high-resolution paleoclimatic records were obtained owing to high sediment accumulation rates, the seismic data from the Pingualuit Crater Lake suggest extremely low sedimentation rates after the retreat of the LIS owing to the absence of tributaries.

Series of submarine canyons and channels observed in the Lower St. Lawrence Estuary (LSLE) provide an opportunity to analyze in great detail the morphology, spatial distribution and modern activity of such systems in a relatively shallow (≤ 300 m) semi-enclosed basin. Based on their geomorphology and physical settings, the canyons and channels were classified into four categories according to their feeding sources (ancient or recent): glacially-fed, river-fed, longshore drift-fed and sediment-starved systems. Their activity was interpreted based on geomorphological characteristics such as the presence of bedforms related to gravity flows, backscatter intensity, axial incision and the presence of rapidly deposited layers in surficial sediments. River-fed deltas were interpreted as inactive, mainly because suspended sediment concentrations at river mouths are low, preventing the generation of hyperpycnal currents or delta-lip failures related to high sediment supply. Longshore drift-fed canyons, present where the coastal shelf narrows, were found to be episodically active probably due to earthquakes or extreme storm events. Unlike other longshore drift-fed canyons observed elsewhere in the world, they are active infrequently because of the modern low rates of sediment supply to their heads. The most active canyons are the sediment-starved type and were observed near Pointe-des-Monts. Their activity is probably due to slope failures and to the presence of strong hydrodynamic processes. Therefore, sediment supply is not the main mechanism responsible for modern canyon and channel activity in the LSLE. However, sediment supply has been an important factor during the formation of the submarine channels and canyons. Their quasi-exclusive occurrence on the Quebec North Shore is attributed to its larger watershed and important sedimentary delivery during deglaciation. The Quebec North Shore watershed is 20 times greater than the Quebec South Shore watershed, which favored the transport of greater volumes of sediment during the early-Holocene. Moreover, the slope proximity to the shore led to the formation of longshore-drift fed systems on the North Shore when sediment supplied to rivers were transferred on a narrow shelf.

The contemporaneous activity and sedimentary processes in a series of inner-shelf submarine canyons located in the Lower St. Lawrence Estuary were examined using high-resolution multibeam bathymetry and backscatter data. The presence of crescent-shaped bedforms (CSBs) displaced upslope at the bottom of the canyons between 2007 and 2012 indicates that they are currently active through the remobilization of sediment by gravity flows. However, the shelf and shores of the region are characterized by the absence of sediment. Our results indicate that gravity flows currently eroding the canyon floors do not transport new material downslope coming from the shelf but rather remobilize in-situ deglacial sediments within the canyon thalweg. We suggest that slope failures and internal tides/waves are responsible for sediment remobilization in these canyons, although their role in the upslope migrating CSBs is unclear. This paper provides evidence that sediment supply is not a prerequisite for the modern activity of inner-shelf submarine canyons when processes such as slope failures and internal tides/waves are frequent enough to remobilize in-situ sediments.

Submarine channels, and the sediment density flows which form them, act as conduits for the transport of sediment, macro-nutrients, fresher water and organic matter from the coast to the deep sea. These systems are therefore significant pathways for global sediment and carbon cycles. However, the conditions that permit or preclude submarine channel formation are poorly understood, especially when in association with marine-terminating glaciers. Here, using swath-bathymetric data from the inner shelf and fjords of northwest and southeast Greenland, we provide the first paper to analyse the controls on the formation of submarine channels offshore of numerous marine-terminating glaciers. These data reveal 37 submarine channels: 11 offshore of northwest Greenland and 26 offshore of southeast Greenland. The presence of channels is nearly always associated with: (1) a stable glacier front, as indicated by the association with either a moraine or grounding-zone wedge; and (2), a consistent seaward sloping gradient. In northwest Greenland, turbidity current channels are also more likely to be associated with larger glacier catchments with higher ice and meltwater fluxes which provide higher volumes of sediment delivery. However, the factors controlling the presence of channels in northwest and southeast Greenland are different, which suggest some complexity about predicting the occurrence of turbidity currents in glacier-influenced settings. Future work on tidewater glacier sediment delivery rates by different subglacial processes, and the role of grain size and catchment/regional geology is required to address uncertainties regarding the controls on channel formation.

This paper reports and describes multibeam echosounder, subbottom profiler and sediment sampling data collected in Lake St-Joseph (southern Quebec), a formerly glacimarine sedimentary basin that has been glacio-isostatically uplifted to form a small lake. Its study provides a unique opportunity for investigating changes in sedimentary environments from a glacial sea to a postglacial lake. Multibeam bathymetry allows the observation of two basins separated by a bathymetric ridge and of mass movement deposits in both basins. High resolution seismic stratigraphy reveals the presence of seven seismic units. These seven units relate to the advance and retreat of the Laurentide ice-sheet over the region. Following ice-retreat, transparent (U3) and high amplitude reflection (U4) units were deposited during the Champlain Sea invasion. The transparent unit likely represents a rapidly retreating glacier, which allowed the deposition of massive silt and clay, whereas the high amplitude reflectors, which are internally composed of transparent to chaotic lenses, are interpreted as the result of a deceleration of ice-retreat or a stabilization of the glacier and of glacio-isostatic rebound. Overlying the Champlain Sea sediments, a unit composed of smaller laminations (U5) suggests that it was deposited during the marine to lacustrine transition, in a paraglacial environment. This is supported by its presence in the northern basin, where the Riviere-aux-Pins mouth is located and its absence in the southern basin, where no river is observed. The bathymetric ridge between the two basins thus limited sediment transport. Following the complete retreat of the Champlain Sea, organic-rich sediments (U7) were deposited in the lake. In the northern basin, the presence of the Riviere-aux-Pins allowed their deposition in the form of rhythmites whereas the absence of rivers in the southern basin resulted in the deposition of an acoustically transparent unit. A mass movement (U6) identified during the deposition of Unit 7 occurred around 1250 AD and is interpreted as earthquake-triggered.

Background Tardive dyskinesia (TD) is a neurological motor complication eventually arising in one-third of patients chronically exposed to antipsychotic drugs. Some orodental peripheral factors have been reported to influence TD. Objective To measure orodental factors such as temporomandibular joint function, static occlusal contacts, and denture condition, and attempt correlations with orofacial TD intensity. Methods In this exploratory cross-sectional pilot study, 31 subjects between 30 and 75 years of age were divided in two groups displaying minimal to mild, or moderate to severe orofacial TD, respectively, and underwent a detailed oral, dental, and prosthetic evaluation to capture various aspects of oral health compared between the two groups. Blinded video-based TD ratings along a validated scale were obtained to compare dentulous and edentulous subjects, and contrast TD intensity in complete denture wearers with and without their own prostheses. Results None of the factors examined tightly correlated with orofacial TD intensity. However, edentulism was associated with a higher median orofacial TD rating compared to the dentulous group ( p = 0.001). Further, a significant intra-subject difference was observed in the edentulous subjects rated with their own complete dentures in place or not ( p = 0.028), the dentures attenuating the mean orofacial ratings by 21.8 ± 7.3%. Conclusion Of all orodental factors considered, only edentulism and complete denture wearing influenced oral TD expression, calling for the close monitoring of the dental status in antipsychotic drug-exposed patients to prevent tooth loss. Further studies to measure the impact of an adequate prosthodontic rehabilitation in edentulous subjects with orofacial TD seem warranted.

Background Drug-induced parkinsonism (DIP) is seen in one third of patients exposed to antipsychotic drugs and may lead to complications related to dysphagia and falls. Aside from skilled neurological examination, no tool has been validated to facilitate detection and follow-up. Objective In this pilot study, three validated screening instruments were tested in an age-biased cohort of schizophrenia patients, including four items of the Liverpool University Neuroleptic Side-Effects Rating Scale (LUNSERS) and two brief questionnaires designed for community survey of parkinsonism. Method Fifty-six subjects living with chronic schizophrenia between 50 and 75 years of age underwent a motor evaluation along the original Unified Parkinson's Disease Rating Scale-section III and answered questions along the selected screening instruments, and results compared to those of 16 patients with Parkinson's disease (PD) and 15 neurologically unimpaired volunteers. Odds ratios, sensitivity, specificity, and their 95% confidence intervals, were calculated. Results All three screening instruments correctly identified the PD state and distinguished PD from healthy participants. Eighteen (32%) schizophrenic patients displayed objective motor signs of parkinsonism. A single item of the LUNSERS (shakiness) significantly distinguished DIP from DIP-free patients, with a sensitivity of 61.1% and a specificity of 83.3%. The positive predictive value was 63.5% and the negative predictive value was 81.9%. The two other screening methods showed insufficient predictive value. Conclusion Apart from a single query on shakiness, none of the tools examined were adequate to screen for DIP in patients treated for schizophrenia. A different instrument is necessary to monitor this important adverse effect in schizophrenia.

In this study, we use records of nitrogen isotope ratios (δ15N), UK’37 temperature estimates, organic carbon and opal percentages from high-resolution sediment cores located in the eastern equatorial Pacific (EEP) to explore the mechanisms linking millennial-scale changes in low-latitude sea surface temperature, water column denitrification and surface productivity to the timing of northern or southern polar climate during the last 100,000 yr. Our results support a hypothesis that the Southern Hemisphere, and its connection to the low latitudes via shallow subsurface ocean circulation, has a primary influence on the biogeochemistry of the EEP. In addition, our results suggest that, during the last glacial stage, denitrification rates fluctuated on millennial timescales in response to water-column ventilation rather than upstream oxidant demand in intermediate-depth waters. However, due to the poor age constraints available for Marine Isotopic Stage (MIS) 3, the EEP sedimentary data presented here could support two conflicting mechanisms, one driven by enhanced intermediate overturning circulation in the Southern Ocean during Heinrich Events/Antarctic Warm Events, implying that subsurface flow rates control thermocline ventilation, and a second one consistent with more sluggish intermediate circulation during Antarctic Warm Events and giving a central role to the temperature control on oxygen solubility in Southern Ocean surface waters.

The present study examined (a) the predictive effect of disruptive boys' attendance to a prevention program (i.e., dosage) on post-intervention academic achievement and behavior and (b) the potential moderating effects of child and family characteristics in this context. The 3-year intervention program included reading, self-regulation, and social skills training for the boys, parental support and skills training for parents, and teacher support. A multiple-screening procedure selected 58 disruptive, low socioeconomic status boys at the age of 6 years for program participation. Multiple regression analyses and logistic regression analyses showed that the number of program sessions attended did not contribute to the prediction of boys' post-intervention disruptive behavior. However, the number of attended sessions was positively related to boys' post-intervention likability, as well as to their post-intervention writing, reading, math, and human science performances. Interaction terms revealed that family constellation moderated the link between program dosage and likability and math success, respectively, whereas boys' IQ moderated the links between dosage and boys' success in writing and math. The discussion stresses the importance of dosage-effect analysis and the examination of moderating variables in this context.

An accurate measurement of the transverse relaxation time T2, and the histogram of T2 in the brain parenchyma can be accomplished in vivo using a multi-echo magnetic resonance imaging sequence. An estimate of the error in the T2 measurement is derived using copper sulfate doped water phantoms. Correction factors are calculated and applied to the signal intensity of each voxel prior to the in vivo T 2 evaluation. These corrected T2 are in good agreement with the theoretical values calculated from copper sulfate concentrations. This technique is then applied to calculate T2 histograms of the brain. The population studied was composed of normal volunteers and multiple sclerosis patients. The corrected T 2 histogram method discriminates the normal control population from the MS population, and also discriminates between relapsing-remitting patients and primary progressive or secondary progressive patients. Moreover using this approach we are able to detect in MS patients a global shift of the T2 of the white mater toward higher values. The results of this study showed that the method is easy to implement and may be used to characterize MS pathology. © 2002 Elsevier Science Inc. All rights reserved.

This study examined the effect of mothers′ familiarity with a permutation task on the performance and monitoring of mother-child dyads during the solution of a cognitive task. In addition, the effect of mothers′ familiarity with the task on children′s independent performance on a similar task during a posttest was investigated. Forty dyads participated in the study. Half of the mothers were familiarized with the task during a pretest. Results indicated that mothers familiarized with the permutation task elicited higher level strategies during dyadic interaction. Task-familiar mothers also let children participate more extensively in the task solution and were more likely to explain strategies than task-unfamiliar mothers. Finally, children of task-familiar mothers were more likely to use systematic strategies at post-test.

The present study examined developmental changes of the cognitive monitoring of family members during a joint problem-solving activity. Boys were observed twice, either with a single parent (n = 22) or with both parents (n = 30), over a two-year period. Family units were asked to solve an unfamiliar task consisting of a permutation task adapted on a microcomputer. Results indicated that the involvement of each participant varied. Parents were taking decisions more often than children whereas children were more involved in the execution of the task. Mothers in one-parent families expressed a greater proportion of metacognitive statements than parents in two-parent families although their affective comments were not as extensive as in two-parent families. Although families did not become more strategic in solving the permutation task over time, they made greater use of metacognitive statements and were more controlling of the activity. This was especially the case for mothers in one-parent families. The role of adults' expertise with regard to the development of self- monitoring abilities in children is discussed within a Vygotskyan perspective.