Derivation of base-line geochemistry, petrography, and isotopic data for the host rocks to the Lucky Strike deposit and comparison with data from other alteration zones, Buchans Mining Camp, Newfoundland

The Buchans ore bodies of central Newfoundland represent some of the highest grade VMS deposits ever mined. These Kuroko-type deposits are also known for the well developed and preserved nature of the mechanically transported deposits. The deposits are hosted in Cambro-Ordovician, dominantly calc-alkaline, bimodal volcanic and epiclastic sequences of the Notre Dame Subzone, Newfoundland Appalachians. Stratigraphic relationships in this zone are complicated by extensively developed, brittledominated Silurian thrust faulting. Hydrothermal alteration of host rocks is a common feature of nearly all VMS deposits, and the recognition of these zones has been a key exploration tool. Alteration of host rocks has long been described to be spatially associated with the Buchans ore bodies, most notably with the larger in-situ deposits. This report represents a base-line study in which a complete documentation of the geochemical variance, in terms of both primary (igneous) and alteration effects, is presented from altered volcanic rocks in the vicinity of the Lucky Strike deposit (LSZ), the largest in-situ deposit in the Buchans camp. Packages of altered rocks also occur away from the immediate mining areas and constitute new targets for exploration. These zones, identified mostly by recent and previous drilling, represent untested targets and include the Powerhouse (PHZ), Woodmans Brook (WBZ) and Airport (APZ) alteration zones, as well as the Middle Branch alteration zone (MBZ), which represents a more distal alteration facies related to Buchans ore-formation. Data from each of these zones were compared to those from the LSZ in order to evaluate their relative propectivity. Derived litho geochemical data served two functions: (i) to define primary (igneous) trends and (ii) secondary alteration trends. Primary trends were established using immobile, or conservative, elements (i. e., HFSE, REE, Th, Ti0₂, Al₂0₃, P₂0₅). From these, altered volcanic rocks were interpreted in terms of composition (e.g., basalt - rhyodacite) and magmatic affinity (e.g., calc-alkaline vs. tholeiitic). The information suggests that bimodality is a common feature of all zones, with most rocks plotting as either basalt/andesite or dacite (or rhyodacite); andesitic senso stricto compositions are rare. Magmatic affinities are more varied and complex, but indicate that all units are arc volcanic sequences. Rocks from the LSZ/MBZ represent a transitional to calc-alkalic sequence, however, a slight shift in key geochemical discriminants occurs between the foot-wall to the hanging-wall. Specifically, mafic and felsic lavas of the foot-wall are of transitional (or mildly calc-alkaline) affinity whereas the hanging-wall rocks are relatively more strongly calc-alkaline as indicated by enriched LREE/HREE and higher ZrN, NbN and other ratios in the latter. The geochemical variations also serve as a means to separate the units (at least the felsic rocks) into hanging-wall and foot-wall sequences, therefore providing a valuable exploration tool. Volcanic rocks from the WBZ/PHZ (and probably the APZ) are more typical of tholeiitic to transitional suites, yielding flatter mantlenormalized REE patterns and lower ZrN ratios. Thus, the relationships between the immediate mining area (represented by LSZ/MBZ) and the Buchans East (PHZ/WBZ) and the APZ are uncertain. Host rocks for all zones consist of mafic to felsic volcanic rocks, though the proportion of pyroclastic and epiclastic rocks, is greatest at the LSZ. Phenocryst assemblages and textures are common in all zones, with minor exceptions, and are not useful for discrimination purposes. Felsic rocks from all zones are dominated by sericiteclay+/- silica alteration, whereas mafic rocks are dominated by chlorite- quartz- sericite alteration. Pyrite is ubiquitous in all moderately altered rocks and minor associated base metal sulphides occur locally. The exception is at Lucky Strike, where stockwork quartzveining contains abundant base-metal mineralization and barite. Rocks completely comprised of chlorite (chloritite) also occur in the LSZ foot-wall. In addition, K-feldspar alteration occurs in felsic volcanic rocks at the MBZ associated with Zn-Pb-Ba and, notably, without chlorite. This zone represents a peripheral, but proximal, zone of alteration induced by lower temperature hydrothermal fluids, presumably with little influence from seawater. Alteration geochemistry was interpreted from raw data as well as from mass balanced (recalculated) data derived from immobile element pairs. The data from the LSZ/MBZ indicate a range in the degree of alteration from only minor to severe modification of precursor compositions. Ba tends to show a strong positive correlation with K₂0, although most Ba occurs as barite. With respect to mass changes, Al₂0₃, Ti0₂ and P₂0₅ were shown to be immobile. Nearly all rocks display mass loss of Na₂O, CaO, and Sr reflecting feldspar destruction. These trends are usually mirrored by K₂0-Rb and MgO addition, indicating sericitic and chloritic alteration, respectively. More substantial gains ofK₂0 often occur in rocks with K-feldspar alteration, whereas a few samples also displayed excessive MgO enrichment and represent chloritites. Fe₂0₃ indicates both chlorite and sulphide formation. Si0₂ addition is almost always the case for the altered mafic rocks as silica often infills amygdules and replaces the finer tuffaceous material. The felsic rocks display more variability in Si0₂. Silicic, sericitic and chloritic alteration trends were observed from the other zones, but not K-feldspar, chloritite, or barite. Microprobe analysis of chlorites, sericites and carbonates indicate: (i) sericites from all zones are defined as muscovite and are not phengitic; (ii) at the LSZ, chlorites ranged from Fe-Mg chlorites (pycnochlorite) to Mg-rich chlorite (penninite), with the latter occurring in the stockwork zone and more proximal alteration facies; (iii) chlorites from the WBZ were typical of those from the more distal alteration facies of the LSZ, plotting as ripidolite to pycnochlorite; (iv) conversely, chlorite from the PHZ plot with Mg-Al-rich compositions (chlinochlore to penninite); and (v) carbonate species from each zone are also varied, with calcite occurring in each zone, in addition to dolomite and ankerite in the PHZ and WBZ, respectively. Lead isotope ratios for galena separates from the different various zones, when combined with data from older studies, tend to cluster into four distinctive fields. Overall, the data plot on a broad mixing line and indicate evolution in a relatively low-μ environment. Data from sulphide stringers in altered MBZ rocks, as well as from clastic sulphides (Sandfill prospect), plot in the Buchans ore field, as do the data for galena from altered rocks in the APZ. Samples from the Buchans East area are even more primitive than the Buchans ores, with lead from the PHZ plotting with the Connel Option prospect and data from the WBZ matching that of the Skidder prospect. A sample from a newly discovered debris flow-type sulphide occurrence (Middle Branch East) yields lead isotope ratios that are slightly more radiogenic than Buchans and plot with the Mary March alteration zone. Data within each cluster are interpreted to represent derivation from individual hydrothermal systems in which metals were derived from a common source.

Seabed photographs taken along OFOS profiles during POLARSTERN cruise PS96 (ANT-XXXI/2 FROSN)

Within the context of the overall ecological working programme Dynamics of Antarctic Marine Shelf Ecosystems (DynAMo) of the PS96 (ANT-XXXI/2) cruise of RV "Polarstern" to the Weddell Sea (Dec 2015 to Feb 2016), seabed imaging surveys were carried out along drift profiles by means of the Ocean Floor Observation System (OFOS) of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) Bremerhaven. The setup and mode of deployment of the OFOS was similar to that described by Bergmann and Klages (2012, doi:10.1016/j.marpolbul.2012.09.018). OFOS is a surface-powered gear equipped with two downward-looking cameras installed side-by-side: one high-resolution, wide-angle still camera (CANON® EOS 5D Mark III; lens: Canon EF 24 f/1.4L II, f stop: 13, exposure time: 1/125 sec; in-air view angles: 74° (horizontal), 53° (vertical), 84° (diagonal); image size: 5760 x 3840 px = 21 MPix; front of pressure resistant camera housing consisting of plexiglass dome port) and one high-definition color video camera (SONY® FCB-H11). The system was vertically lowered over the stern of the ship with a broadband fibre-optic cable, until it hovers approximately 1.5 m above the seabed. It was then towed after the slowly sailing ship at a speed of approximately 0.5 kn (0.25 m/s). The ship's Global Acoustic Positioning System (GAPS), combining Ultra Short Base Line (USBL), Inertial Navigation System (INS) and satellite-based Global Positioning System (GPS) technologies, was used to gain highly precise underwater position data of the OFOS. During the profile, OFOS was kept hanging at the preferred height above the seafloor by means of the live video feed and occasional minor cable-length adjustments with the winch to compensate small-scale bathymetric variations in seabed morphology. Information on water depth and height above the seafloor were continuously recorded by means of OFOS-mounted sensors (GAPS transponder, Tritech altimeter). Three lasers, which are placed beside the still camera, emit parallel beams and project red light points, arranged as an equilateral triangle with a side length of 50 cm, in each photo, thus providing a scale that can be used to calculate the seabed area depicted in each image and/or measure the size of organisms or seabed features visible in the image. In addition, the seabed area depicted was estimated using altimeter-derived height above seafloor and optical characteristics of the OFOS still camera. In automatic mode, a seabed photo, depicting an area of approximately 3.45 m**2 (= 2.3 m x 1.5 m; with variations depending on the actual height above ground), was taken every 30 seconds to obtain series of "TIMER" stills distributed at regular distances along the profiles that vary in length depending on duration of the cast. At a ship speed of 0.5 kn, the average distance between seabed images was approximately 5 m. Additional "HOTKEY" photos were taken from interesting objects (organisms, seabed features, such as putative iceberg scours) when they appeared in the live video feed (which was also recorded, in addition to the stills, for documentation and possible later analysis). If any image from this collection is used, please cite the reference as given above.

Effects of Natural Organic Matter on the Dissolution Kinetics and Bioavailability of Metal Oxide Nanoparticles

The rapid development of nanotechnology and wider applications of engineered nanomaterials (ENMs) in the last few decades have generated concerns regarding their environmental and health risks. After release into the environment, ENMs undergo aggregation, transformation, and, for metal-based nanomaterials, dissolution processes, which together determine their fate, bioavailability and toxicity to living organisms in the ecosystems. The rates of these processes are dependent on nanomaterial characteristics as well as complex environmental factors, including natural organic matter (NOM). As a ubiquitous component of aquatic systems, NOM plays a key role in the aggregation, dissolution and transformation of metal-based nanomaterials and colloids in aquatic environments.

The goal of this dissertation work is to investigate how NOM fractions with different chemical and molecular properties affect the dissolution kinetics of metal oxide ENMs, such as zinc oxide (ZnO) and copper oxide (CuO) nanoparticles (NPs), and consequently their bioavailability to aquatic vertebrate, with Gulf killifish (Fundulus grandis) embryos as model organisms.

ZnO NPs are known to dissolve at relatively fast rates, and the rate of dissolution is influenced by water chemistry, including the presence of Zn-chelating ligands. A challenge, however, remains in quantifying the dissolution of ZnO NPs, particularly for time scales that are short enough to determine rates. This dissertation assessed the application of anodic stripping voltammetry (ASV) with a hanging mercury drop electrode to directly measure the concentration of dissolved Zn in ZnO NP suspensions, without separation of the ZnO NPs from the aqueous phase. Dissolved zinc concentration measured by ASV ([Zn]ASV) was compared with that measured by inductively coupled plasma mass spectrometry (ICP-MS) after ultracentrifugation ([Zn]ICP-MS), for four types of ZnO NPs with different coatings and primary particle diameters. For small ZnO NPs (4-5 nm), [Zn]ASV was 20% higher than [Zn]ICP-MS, suggesting that these small NPs contributed to the voltammetric measurement. For larger ZnO NPs (approximately 20 nm), [Zn]ASV was (79±19)% of [Zn]ICP-MS, despite the high concentrations of ZnO NPs in suspension, suggesting that ASV can be used to accurately measure the dissolution kinetics of ZnO NPs of this primary particle size.

Using the ASV technique to directly measure dissolved zinc concentration, we examined the effects of 16 different NOM isolates on the dissolution kinetics of ZnO NPs in buffered potassium chloride solution. The observed dissolution rate constants (kobs) and dissolved zinc concentrations at equilibrium increased linearly with NOM concentration (from 0 to 40 mg-C L-1) for Suwannee River humic acid (SRHA), Suwannee River fulvic acid and Pony Lake fulvic acid. When dissolution rates were compared for the 16 NOM isolates, kobs was positively correlated with certain properties of NOM, including specific ultraviolet absorbance (SUVA), aromatic and carbonyl carbon contents, and molecular weight. Dissolution rate constants were negatively correlated to hydrogen/carbon ratio and aliphatic carbon content. The observed correlations indicate that aromatic carbon content is a key factor in determining the rate of NOM-promoted dissolution of ZnO NPs. NOM isolates with higher SUVA were also more effective at enhancing the colloidal stability of the NPs; however, the NOM-promoted dissolution was likely due to enhanced interactions between surface metal ions and NOM rather than smaller aggregate size.

Based on the above results, we designed experiments to quantitatively link the dissolution kinetics and bioavailability of CuO NPs to Gulf killifish embryos under the influence of NOM. The CuO NPs dissolved to varying degrees and at different rates in diluted 5‰ artificial seawater buffered to different pH (6.3-7.5), with or without selected NOM isolates at various concentrations (0.1-10 mg-C L-1). NOM isolates with higher SUVA and aromatic carbon content (such as SRHA) were more effective at promoting the dissolution of CuO NPs, as with ZnO NPs, especially at higher NOM concentrations. On the other hand, the presence of NOM decreased the bioavailability of dissolved Cu ions, with the uptake rate constant negatively correlated to dissolved organic carbon concentration ([DOC]) multiplied by SUVA, a combined parameter indicative of aromatic carbon concentration in the media. When the embryos were exposed to CuO NP suspension, changes in their Cu content were due to the uptake of both dissolved Cu ions and nanoparticulate CuO. The uptake rate constant of nanoparticulate CuO was also negatively correlated to [DOC]×SUVA, in a fashion roughly proportional to changes in dissolved Cu uptake rate constant. Thus, the ratio of uptake rate constants from dissolved Cu and nanoparticulate CuO (ranging from 12 to 22, on average 17±4) were insensitive to NOM type or concentration. Instead, the relative contributions of these two Cu forms were largely determined by the percentage of CuO NP that was dissolved.

Overall, this dissertation elucidated the important role that dissolved NOM plays in affecting the environmental fate and bioavailability of soluble metal-based nanomaterials. This dissertation work identified aromatic carbon content and its indicator SUVA as key NOM properties that influence the dissolution, aggregation and biouptake kinetics of metal oxide NPs and highlighted dissolution rate as a useful functional assay for assessing the relative contributions of dissolved and nanoparticulate forms to metal bioavailability. Findings of this dissertation work will be helpful for predicting the environmental risks of engineered nanomaterials.

Suicide and deliberate self harm in older Irish adults

Background: Hospital-treated deliberate self harm and suicide among older adults have rarely been examined at a national level. Methods: The Irish Central Statistics Office provided suicide and undetermined death data for 1980-2006. The National Registry of Deliberate Self Harm collected data relating to deliberate self harm presentations made in 2006-2008 to all 40 Irish hospital emergency departments. Results: Rates of female suicide among older adults (over 55 years) were relatively stable in Ireland during 1980-2006 whereas male rates increased in the 1980s and decreased in more recent decades. Respectively, the annual male and female suicide and undetermined death rate was 22.1 and 7.6 per 100,000 in 1997-2006. Male and female deliberate self harm was 3.0 and 11.0 times higher at 67.4 and 83.4 per 100,000, respectively. Deliberate self harm and suicide decreased in incidence with increasing age. Deliberate self harm generally involved drug overdose (male: 72%; female 85%) or self-cutting (male: 15%; female 9%). The most common methods of suicide were hanging (41%) and drowning (29%) for men and drowning (39%) and drug overdose (24%) for women. City and urban district populations had the highest rates of hospital-treated self harm. The highest suicide rates were in urban districts. Conclusions: Older Irish adults have high rates of hospital-treated deliberate self harm but below average rates of suicide. Drowning was relatively common as a method of suicide. Restricting availability of specific medications may reduce both forms of suicidal behavior.

Geochemical composition of minerals obtained from ODP Sites 180-1109, 180-1117 and 180-1118

During the last 8 m.y. the Papuan Peninsula region of Papua New Guinea has been affected by extension which opened the Woodlark Basin. The present-day spreading tip is located at the foot of the Moresby Seamount, a crustal block whose northern flank is an active low-angle normal fault related to this extension. During Ocean Drilling Program Leg 180 (7 June-11 August 1998), 11 sites (1108-1118) were drilled along a north-south-trending transect across the Woodlark Basin just ahead of the spreading tip. Four of these sites (1118, 1109, 1114, and 1117) reached the crystalline basement, which is composed of diabase and gabbro. Sites 1118 and 1109, located on the Woodlark Rise, belong to the hanging wall block, and Sites 1114 and 1117, located on the crest of the Moresby Seamount, belong to the footwall block and the fault zone itself. Most of the basalt, diabase, and gabbro that were recovered show a well-preserved magmatic texture. The diabase, which is the most abundant rock type, has a coarse-grained ophitic texture composed of poikilitic clinopyroxene including radiating, locally skeletal plagioclase laths with interstitial iron oxide grains. Secondary mineralogy consists of chlorite, zeolite, calcite, albite, and quartz. The gabbro shows a medium-grained granular texture. The magmatic mineralogy consists of euhedral laths of plagioclase and anhedral interstitial clinopyroxene. Secondary mineralogy consists of a magnesio to actinolitic hornblende, chlorite, clinozoisite, zeolite, quartz, and calcite. The retrograde metamorphic evolution of both gabbro and diabase occurred under low amphibolite to subgreenschist facies conditions associated mainly with brittle deformation and the development of a local low-temperature shear zone. This shows no evidence for high thermal gradient in the crust during the continental rifting.

Oceanographic data, oxygen and methane concentrations, and C-CH4 isotope ratios measured at Jaco Scar

Methane (CH4) concentrations and CH4 stable carbon isotopic composition (d13CCH4) were investigated in the water column within Jaco Scar. It is one of several scars formed by massive slides resulting from the subduction of seamounts offshore Costa Rica, a process that can open up structural and stratigraphical pathways for migrating CH4. The release of large amounts of CH4 into the adjacent water column was discovered at the outcropping lowermost sedimentary sequence of the hanging wall in the northwest corner of Jaco Scar, where concentrations reached up to 1,500 nmol L-1. There CH4-rich fluids seeping from the sedimentary sequence stimulate both growth and activity of a dense chemosynthetic community. Additional point sources supplying CH4 at lower concentrations were identified in density layers above and below the main plume from light carbon isotope ratios. The injected CH4 is most likely a mixture of microbial and thermogenic CH4 as suggested by d13CCH4 values between -50 and -62 per mil Vienna Pee Dee Belemnite. This CH4 spreads along isopycnal surfaces throughout the whole area of the scar, and the concentrations decrease due to mixing with ocean water and microbial oxidation. The supply of CH4 appears to be persistent as repeatedly high CH4 concentrations were found within the scar over 6 years. The maximum CH4 concentration and average excess CH4 concentration at Jaco Scar indicate that CH4 seepage from scars might be as significant as seepage from other tectonic structures in the marine realm. Hence, taking into account the global abundance of scars, such structures might constitute a substantial, hitherto unconsidered contribution to natural CH4 sources at the seafloor.

Structural evolution of the Lesser Himalayan fold-thrust belt of west central Nepal

The Lesser Himalayan fold-thrust belt on the south flank of the Jajarkot klippe in west central Nepal was mapped in detail between the Main Central thrust in the north and the Main Boundary thrust in the south. South of the Jajarkot klippe, the fold-thrust belt involves sandstone, shale and carbonate rocks that are unmetamorphosed in the foreland and increase in metamorphic grade with higher structural position to sub-greenschist facies towards the hinterland. The exposed stratigraphy is correlative with the Proterozoic Ranimata, Sangram, Galyang, Syangia Formations and Lakharpata Group of Western Nepal and overlain by the Paleozoic Tansen and Kali Gandaki Groups. Based on field mapping and cross-section construction, three distinct thrust sheets were identified separated by top-to-the-south thrust faults. From the foreland (south) to the hinterland (north), the first thrust sheet in the immediate hanging wall of the Main Boundary thrust defines an open syncline. The second thrust sheet contains a very broad synformal duplex, which is structurally stacked against the third thrust sheet containing a homoclinal panel of the oldest exposed Proterozoic stratigraphy. Outcrop scale folds throughout the study area are predominantly south vergent, open, and asymmetric reflecting the larger regional scale folding style, which corroborate the top-to-the-south deformation style seen in the faults of the region. Field techniques were complemented with microstructural and quartz crystallographic c-axis preferred orientation analyses using a petrographic microscope and a fabric analyzer, respectively. Microstructural analysis identified abundant strain-induced recrystallization textures and occasional occurrences of top-to-the-south shear-sense indicators primarily in the hinterland rocks in the immediate footwall of the Main Central Thrust. Top-to-the-south shearing is also supported by quartz crystallographic c-axis preferred orientations. Quartz recrystallization textures indicate an increase in deformation temperature towards the Main Central thrust. A line balance estimate indicates that approximately 15 km of crustal shortening was accommodated by folding and faulting in the fold-thrust belt south of the Jajarkot klippe. Additionally, estimations of shortening velocity suggest that the shortening velocity operating in this section of the fold-thrust belt between 23 to 14 Ma was slower than what is currently observed as a result of the ongoing deformation of the Sub-Himalayan fold-thrust belt.

Demographic trends in suicide in the UK and Ireland 1980 - 2010.

Background Ireland has the 17th highest suicide rate in the EU and the 4th highest among 15 to 24-year-old males (WHO 2012). Suicide is the leading cause of death in this age group; death by hanging accounted for 69 % of suicides in 2010. Methods This study examines youth suicide rates from 1980 to 2010 in Ireland and compares them to the rates in Northern Ireland, Scotland, England and Wales. Irish data were obtained from the Central Statistics Office and their annual reports on Vital Statistics. Northern Irish data were obtained from the Northern Ireland Statistics and Research Agency website; Scottish data were from the General Register Office for Scotland and English/Welsh data from the Office for National Statistics website. Results There has been a threefold increase in young male suicide in Ireland over the past three decades (8.9 - 29.7 per 100,000). In contrast, there has been approximately a threefold reduction in deaths by road traffic accidents in young men in the same period (42.7 - 16.2 per 100,000). Suicide rates in young men are similar in Scotland and Northern Ireland for the same period but are 50 % lower in England and Wales. Despite the rates of hanging as a method of suicide increasing in all jurisdictions, the overall rate in England and Wales has continued to decline. Conclusion The suicide rate in Ireland remains very high and strategies to address this are urgently required. Our study indicates that national suicide prevention strategies can be effective.

Crime and Punishment.

The study of Victorian crime and punishment is a rich area of research that has attracted the interest not only of literary scholars but also of social historians, legal historians, and criminologists. Related scholarship therefore often situates itself at the intersection of traditional disciplinary boundaries, facilitating interdisciplinary conversation. Crime and punishment was a pressing issue for the Victorians and provoked a wealth of responses from contemporaneous commentators in literature, culture, and science. As a new phase of industrialization brought immense wealth for some and abject poverty for others, Victorian urban centers in particular were afflicted by crime. Without an effective system of social welfare in place, social inequality and deprivation drove women, men, and children into petty crime and more serious offenses, resulting in severe punishment ranging from incarceration via penal transportation to hanging. Public executions, not abolished until 1868, attracted huge crowds of spectators, including authors such as Charles Dickens and William Thackeray, who wrote about these experiences. A forerunner of the popular press, street literature conveyed and illustrated these events for a broad audience. Execution broadsides of famous cases, printing the alleged last lamentations of convicts on the scaffold in verse, are estimated to have sold by the million. As the legal system was undergoing reform (comprising changes in legal evidence procedure, divorce law, women’s property rights, and punishment for sexual offenses, for example), sensational trials caused furor and stimulated commentary in literature and the media. Crime and punishment was discussed in a range of literary and popular genres, poetry, and reformist writing. The “Newgate School” of fiction was accused of glamorizing crime, and the popular penny dreadfuls were feared to corrupt public morals. Sensational fiction in the 1860s, which often drew on real-life criminal cases and newspaper reports, depicted the supposedly respectable middle-class family home as a center of transgression. Similarly, detective fiction typically focused on crime in the world of the middle classes. For the student new to the subject of crime and punishment, this area’s interdisciplinary nature can pose an initial challenge.

Discontinuous Galerkin Computation of the Maxwell Eigenvalues on Simplicial Meshes

This paper is concerned with the discontinuous Galerkin approximation of the Maxwell eigenproblem. After reviewing the theory developed in [5], we present a set of numerical experiments which both validate the theory, and provide further insight regarding the practical performance of discontinuous Galerkin methods, particularly in the case when non-conforming meshes, characterized by the presence of hanging nodes, are employed.

Behavioural studies on the ethanol leaf extract of Grewia carpinifolia in Wistar rats.

Background: Grewia carpinifolia is a plant commonly used in the tropics to manage various central nervous system (CNS) disorders. However, despite its widespread use no scientific work has been reported to validate these claims. Objectives: To evaluate the activity of G. carpinifolia as it affects behaviour using animal model. Methods: Twenty five adult Wistar rats were randomly divided into five groups (A-E). Group A served as control (given only distilled water), Groups B,C, D and E were administered with single oral dose of ethanol extract of G. carpinifolia leaf at 100, 200, 400 and 800 mg/kg body weight respectively for twenty eight days consecutively. Subsequently, open field test, negative geotaxis and hanging wire test were performed. Body and brain weights were measured and histological examination of the brain was also performed. Results: At the tested doses, the extract significantly increased the time spent on the hanging wire and decreased locomotor activity at 800 mg/kg. No significant difference was observed in body and brain weights of extract treated groups when compared with the control. No visible histological lesion was also observed. Conclusion: The plant extract may improve muscular strength at tested doses and possess CNS depressant activity at 800 mg/ kg.

Tectonics of Central and Eastern California, Late Cretaceous to Modern

The Late Cretaceous to Modern tectonic evolution of central and eastern California has been studied for many decades, with published work generally focusing on specific geographic areas and time periods. The resulting literature leaves the reader, whether graduate student, faculty member, or layperson, wondering what a coherently integrated tectonic evolution might look like, or if it would be at all possible to undertake such a task. This question is the common thread weaving together the four studies presented in this work. Each of the individual chapters is targeted at a specific location and time period which I have identified as a critical yet missing link in piecing together a coherent regional tectonic story. In the first chapter, we re-discover a set of major west down normal faults running along the western slope of the southern Sierra, the western Sierra fault system (WSFS). We show that one of these faults was offset by roughly a kilometer in Eocene time, and that this activity directly resulted in the incision of much of the relief present in modern Kings Canyon. The second chapter is a basement landscape and thermochronometric study of the hanging wall of the WSFS. New data from this study area provide a significant westward expansion of basement thermochronometric data from the southern Sierra Nevada batholith. Thermal modeling results of these data provide critical new constraints on the early exhumation of the Sierra Nevada batholith, and in the context of the results from Chapter I, allow us to piece together a coherent chronology of tectonic forcings and landscape evolution for the southern Sierra Nevada. In the third chapter, I present a study of the surface rupture of the 1999 Hector Mine earthquake, a dextral strike slip event on a fault in the Eastern California Shear Zone (ECSZ). New constraints on the active tectonics in ECSZ will help future studies better resolve the enigmatic mismatch between geologic slip rates and geodetically determined regional rates. Chapter IV is a magnetostratigraphic pilot study of the Paleocene Goler Formation. This study provides strong evidence that continued investigation will yield new constraints on the depositional age of the only fossil-bearing Paleocene terrestrial deposit on the west coast of North America. Each of these studies aims to provide important new data at critical missing links in the tectonic evolution of central and eastern California.

Autour des nouvelles valorisations des collections permanentes au musée : le cas de l'exposition Encounters : New Art from Old

Dans le cadre de la célébration du nouveau millénaire, la National Gallery de Londres a organisé l'exposition Encounters: New Art from Old (14 juin - 17 septembre 2000). La formule consistait à inviter vingt-cinq artistes contemporains à choisir une œuvre de la collection permanente du musée et à s'en inspirer afin d'en créer une nouvelle. Certaines des œuvres produites pour l’occasion ont été exposées près de leurs sources dans les salles historiques de la collection du musée. Ce mémoire examine comment la formule de cette exposition et son accrochage anachronique agissent de façon directe sur la temporalité de la collection historique en invitant à sa réactualisation, et à la mise en valeur de la création. Il situe cette formule dans le cadre d’un regain d’intérêt pour les collections, décortique la sélection des artistes par le musée et la sélection des œuvres de la collection par les artistes. Il propose aussi une classification des modalités par lesquelles ceux-ci ré-interprètent la tradition. Enfin, en s’appuyant sur la théorie de la réception, ce mémoire considère les réponses générées par l’exposition : celles des artistes aux œuvres de leurs prédécesseurs, celles des critiques et celles du public.

Autour des nouvelles valorisations des collections permanentes au musée : le cas de l'exposition Encounters : New Art from Old

Dans le cadre de la célébration du nouveau millénaire, la National Gallery de Londres a organisé l'exposition Encounters: New Art from Old (14 juin - 17 septembre 2000). La formule consistait à inviter vingt-cinq artistes contemporains à choisir une œuvre de la collection permanente du musée et à s'en inspirer afin d'en créer une nouvelle. Certaines des œuvres produites pour l’occasion ont été exposées près de leurs sources dans les salles historiques de la collection du musée. Ce mémoire examine comment la formule de cette exposition et son accrochage anachronique agissent de façon directe sur la temporalité de la collection historique en invitant à sa réactualisation, et à la mise en valeur de la création. Il situe cette formule dans le cadre d’un regain d’intérêt pour les collections, décortique la sélection des artistes par le musée et la sélection des œuvres de la collection par les artistes. Il propose aussi une classification des modalités par lesquelles ceux-ci ré-interprètent la tradition. Enfin, en s’appuyant sur la théorie de la réception, ce mémoire considère les réponses générées par l’exposition : celles des artistes aux œuvres de leurs prédécesseurs, celles des critiques et celles du public.

Suicide among young people and adults in Ireland: method characteristics, toxicological analysis and substance abuse histories compared

Objective: Information on factors associated with suicide among young individuals in Ireland is limited. The aim of this study was to identify socio-demographic characteristics and circumstances of death associated with age among individuals who died by suicide. Methods: The study examined 121 consecutive suicides (2007–2012) occurring in the southern eastern part of Ireland (Cork city and county). Data were obtained from coroners, family informants, and health care professionals. A comparison was made between 15-24-year-old and 25-34-year-old individuals. Socio-demographic characteristics of the deceased, methods of suicide, history of alcohol and drug abuse, and findings from toxicological analysis of blood and urine samples taken at post mortem were included. Pearson’s χ2 tests and binary logistic regression analysis were performed. Results: Alcohol and/or drugs were detected through toxicological analysis for the majority of the total sample (79.5%), which did not differentiate between 15-24-year-old and 25-34-year-old individuals (74.1% and 86.2% respectively). Compared to 25-34-year-old individuals, 15-24-year-old individuals were more likely to engage in suicide by hanging (88.5%). Younger individuals were less likely to die by intentional drug overdose and carbon monoxide poisoning compared to older individuals. Younger individuals who died between Saturday and Monday were more likely to have had alcohol before dying. Substance abuse histories were similar in the two age groups. Conclusion: Based on this research it is recommended that strategies to reduce substance abuse be applied among 25-34-year-old individuals at risk of suicide. The wide use of hanging in young people should be taken into consideration for future means restriction strategies.