582 research outputs found
Corporate Aiding and Abetting Liability Under the Alien Tort Statute: A Legislative Prerogative
Since the landmark decision in FilĂĄrtiga v. Pena-Irala, U.S. courts have struggled determining actionable claims under the enigmatic Alien Tort Statute (ATS). While the Supreme Court recognized the viability of the ATS as a jurisdictional statute in Sosa v. Alvarez-Machain, its scope was restricted to an amorphous âeighteenth century paradigm.â This model has proven to be a murky standard. One of the most contentious and uncertain claims under the ATS involves corporate liability for aiding and abetting human rights violations. This Comment argues that based upon the limited holding of Sosa, aiding and abetting liability would not be recognized as an actionable claim under the ATS. Therefore, similar to the Torture Victim Protection Act, it is Congressâs role to clarify the ATS and ensure that victims of human rights are able to hold complicit corporations liable
Applying Computational Methods to Interpret Experimental Results in Tribology and Enantioselective Catalysis
Computational methods are rapidly becoming a mainstay in the field of chemistry. Advances in computational methods (both theory and implementation), increasing availability of computational resources and the advancement of parallel computing are some of the major forces driving this trend.
It is now possible to perform density functional theory (DFT) calculations with chemical accuracy for model systems that can be interrogated experimentally. This allows computational methods to supplement or complement experimental methods. There are even cases where DFT calculations can give insight into processes and interactions that cannot be interrogated directly by current experimental methods.
This work presents several examples of the application of computational methods to the interpretation and analysis of experimentally obtained results. First, triobological systems were investigated primarily with full-potential linearized augmented plane wave (FLAPW) method DFT calculations. Second, small organic molecules adsorbed on Pd(111) were studied using projector-augmented wave (PAW) method DFT calculations and scanning tunneling microscopy (STM) image simulations to investigate molecular interactions involved in enantioselective heterogeneous catalysis.
A method for method for calculating pressure-dependent shear properties of model boundary-layer lubricants is demonstrated. The calculated values are compared with experimentally obtained results.
For the case of methyl pyruvate adsorbed on Pd(111), DFT-calculated adsorption energies and structures are used along with STM simulations to identify species observed by STM imaging. A previously unobserved enol species is discovered to be present along with the expected keto species.
The information about methyl pyruvate species on Pd(111) is combined with previously published studies of S-α-(1-naphthyl)-ethylamine (NEA) to understand the nature of their interaction upon coadsorption on Pd(111). DFT calculated structures and energies are used to identify potential docking complexes and STM simulations are compared to the experimental STM images
Minimum entropy deconvolution: a novel processing technique for refraction seismology
Most deconvolution techniques developed for reflection seismology suffer from the need to make assumptions about the disturbing function and the reflection series. In refraction seismology such assumptions are generally not valid. The Minimum Entropy Deconvolution (MED) technique of Wiggins (1978) requires no a priori knowledge of the phase characteristics of the disturbing function, nor does it assume the impulse response of the Earth's transmission path to be a white noise series. As such, it may be applied to short windows of refraction data containing only a few arrivals. The process seeks to simplify the representation of the input data, yielding an output of a small number of spikes. In this way the picking of arrivals on a refraction record is made much easier. By applying the technique to each trace independently, true arrivals may be distinguished from spurious spikes by correlation from one trace to the next
Criminal LawâAdmissibility of Confessions
State v. Moore recently held that only two proper grounds exist for excluding a confession from evidence in a criminal trial: That it was obtained in violation of the due process clause of the fourteenth amendment to the federal constitution or that it has not met the test provided by Washington statute. The Washington Constitution provides that, no person shall be compelled in any criminal case to give evidence against himself . . . \u27 But the court held that this provision does not apply to the admissibility of confessions. The defendant had been convicted of second degree burglary and grand larceny. He sought reversal on the ground that, since he did not testify, admission of his confessions violated the self-incrimination provision
Plant Mediated Effects on Tritrophic Interactions in the Solanaceae-Hornworm System
Top-down pressure from parasites is thought to be a key driver in herbivore diet breath, but studies investigating the evolution of food plant shifts as a defense against natural enemies in the environment are still lacking in the literature. I examined how plants alter insect-enemy interactions for a specialist herbivore utilizing solanaceous food plants, Manduca sexta (the tobacco hornworm) and the parasitoid wasp, Cotesia congregata, as a model. In this study, I documented parasite infections in a field population of M. sexta, and then investigated from an eco-immunological perspective how plant toxins influence susceptibility to parasites in order to explain food plant choice. My research demonstrates that M. sexta exhibits a negative preference-performance relationship with plants in the Solanaceae. This is likely to gain protection from parasitoid attack via direct and indirect effects from plants on herbivore physiology. I show that herbivores are unpalatable and toxic to natural enemies when they consume more noxious host plants, but also provide a subsequent explanation for the adaptive value and maintenance of this interaction; specific plant secondary metabolites alter herbivore immune activity, where for M. sexta nicotine demonstrates immunotherapeutic properties by enhancing this insectâs phenoloxidase activity. I also examined phenotypic plasticity in caterpillar immune responses to nonlethal cues from natural enemies. Upon studying non-consumptive effects of natural enemies on M. sexta in the presence of C. congregata and the spined soldier bug, Podisus maculiventris, my work suggests that M. sexta generally accelerates their development in the presence of natural enemies at the cost of some immune defenses, implying a resource allocation tradeoff to physiological development and immunity. Placed within a community level context, M. sexta can mitigate the consumptive and nonconsumptive effects parasitoids have on this herbivoreâs physiology by utilizing a food resource in parasite burdened habitats that increases direct resistance to parasites and also improves immune activity, even at the cost of development. Following this, I investigated the consequences of crop domestication on plant-insect-parasitoid interaction via changes in plant traits for direct defense against herbivores and altered plant volatile signaling of natural enemies. I demonstrated that domesticated chili peppers showed no loss of plant direct defenses to M. sexta compared to wild peppers and that crop peppers had increased attraction and efficiency of parasitoids. This highlighted the context-dependent nature domestication has on trophic interactions and emphasizes the need for dedicated investigation in each unique crop system
THE SHORT- AND LONG- TERM EFFECT OF ZINC AND COPPER CONTAMINATION ON SOIL MICROBIAL FUNCTIONS
Soil microbial functions are vital for maintaining soil health and are therefore also essential for the provision of services required to support human and ecological health. The inadvertent release of trace metals into soil ecosystems through their extraction, processing, and use of metal ores has led to elevated soil trace metal concentrations worldwide. To preserve soil ecosystem functions and soil health, soil regulatory limits that define acceptable limits of trace metals in the environment need to be set. This is done to reduce the exposure of the soil microbial community to potentially hazardous and toxic substances. However, no single concentration of trace metals can be used to ensure the universal protection of all soil ecosystems. There is therefore a need to define the safe limits of exposure to trace metals in different land-uses. Considerable evidence shows soil microbial functions are affected by trace metal contamination in the short term but are restored over time. However, the long-term effect of trace metals on soil microbial functions is poorly understood. Much of the available data on adaptation is derived from studies focused on agricultural soils in Europe. This study aimed to examine soil enzyme activity across a range of different soil types and determine the long-term effects of zinc and copper contamination, focusing on artificially managed and natural systems, such as agricultural, urban, and anthropic soils, grassland, and forest soil. Initially this investigation validated new methods to determine soil enzyme activity. Standard methods of assessing soil enzyme activity require significant quantities of soil to be collected to then assess contaminated sites and determine toxicity. This experiment aimed to reduce the overall quantity of soil required by an order of magnitude. The assessment of soil nutrient cycling forms a part of all site investigations carried out by Canadian risk assessors. One of the key factors influencing the cost and therefore the scope and size of any potential investigation is the transportation of soils from a site to laboratories for experimentation. Therefore, a low soil requirement assay would significantly expand the potential for site investigations into nutrient cycling. This work demonstrates the validity of a low soil requirement nutrient cycling enzyme (phosphorus, sulfur, and carbon) assay and functional (nitrification) assay. These assays were applied to investigate different soil remediation treatments as part of a site investigation. Heterotrophic and autotrophic nitrification responded differently to lime addition over a decade and the assay demonstrated the effectiveness of different soil treatments (biochar, smectite) and hydro-seeding on soil enzyme activities. The central research of this work focused the soil enzyme activities of 18 soils from across Western Canada. Providing a clear demonstration of the capability of soil enzyme assays for terrestrial eco-toxicity assessment and how this method meets the requirements of the CCME for the assessment of contaminated sites and determining soil quality criteria. This experiment also demonstrated the importance of soil properties and land-use. The experiment provides a range of eco-toxicity data and the first steps towards making soil enzyme assessment a part of the Canadian regulatory regime. This study used North American soils from a range of land-uses to identify differences in adaptation rate and sensitivity, and aimed to evaluate methods used to assess the hazards from trace metals using spiked soils. First, soils (n=18) were spiked with zinc (Zn) and copper (Cu) applied at eight nominal concentrations (0, 300, 1000, 2000, 3000, 5000, 10,000, and 20,000 mgkgâ1. Dose-response curves were then determined for enzyme activities (nitrification, dehydrogenase, arylsulphatase, and acid phosphatase). Land-use was shown to be a factor (P dehydrogenase > arylsulfatase > acid phosphatase. Soils were then monitored to identify adaptation of these microbial functions over 180 days. All soils enzyme activity responses showed adaptation to both zinc and copper over time. The relative sensitivity of each enzyme activity remained consistent after adaptation had occurred. Finally the long term consequences of the adaptation to trace metals by the soil microbial community were investigated. This study tested whether adaptation to a severe stress (trace metals) affects resistance or resilience to a subsequent mild stress. The resistance, resilience, and relative soil stability index (RSSI) of soils were determined for heat (60°C for 24h) and moisture stress, applied as short- term secondary stresses. Soils that had adapted to zinc and copper were not less resilient to additional stresses after adaption, than before recovery. The results of this experiment suggest that activity is a good indicator of soil microbial health but metal concentration is not. Metal speciation was determined using synchrotron-based X-ray Absorption Spectroscopy (XAS) at the Canadian Light Source Inc. Specifically Zn k-edge near-edge structures (XANES) data were collected at the HXMA beamline (06-ID1). Overall these studies provide new insights into the long-term consequences of Zn and Cu in soils. This study showed that soils dosed with zinc in the form of ZnSO4 did not undergo the changes in metal speciation to become less available, which may have been expected. Soil zinc speciation remained consistent overtime and across soils either over time or soil in the most available form of zinc (aqueous zinc). In conclusion, detailed analysis of soils artificially contaminated with zinc and copper in this study allowed the long term consequences for soil microbial functioning to be studied in greater detailed than they have been before. This gave an improved understanding of the effects of zinc and copper to a range of soils. It also improved the understanding of how soils artificially contaminated with metals for hazard testing differ from field contaminated soils. This study provides an improvement in the understanding of how microbial data can be incorporated into soil quality guidelines for Canadian soils
A Professional Experience Learning Community for Pre-service Secondary Mathematics Teachers
This paper reports the development and implementation of a collaborative professional experience learning community for a group of nine pre-service secondary mathematics teachers. The pre-service teachers and their methods lecturer made 12 school visits over one academic year to a local secondary school. The pre-service teachers observed and co-taught problem-solving lessons in two Year 8 classes. They discussed the lessons with the teacher and the university lecturer, and later posted reflective comments to an online forum. Data from questionnaires, interviews, and reflections indicate that participation in the learning community helped pre-service teachers make stronger links between theory and practice, learn from each other, and become more reflective about problem-solving teaching approaches
Perspectives of mental health clinicians on physical health of young people with early psychosis
The aim of this study is to explore the views and understanding of youth mental health clinicians with regard to the physical health of young people with early psychosis and their perspectives on lifestyle interventions improving the health and well-being of young people with early psychosis. Physical health disparities leading to premature mortality among people with mental illness are well evident in the literature. Mental health and physical health are directly correlated. The risk of poor physical health often begins before the onset of mental ill health. Young people with early psychosis are highly susceptible to poor physical health. A co-designed integrated approach focusing on early prevention and intervention in overall well-being and health is imminent for this targeted population to prevent poor physical health trajectory across the lifespan. Ten clinicians were recruited and participated in this study through semi-structured interviews. Five themes were identified: (i) Impact of early psychosis, (ii) Focus of care, (iii) Conversations around physical health, (iv) Co-location of specialist roles and (v) Health literacy. The findings of this study confirm the dimensional impact of early psychosis on the well-being and health of young people through the vicious cycle of early psychosis. Promotion of health literacy along with social connectedness and elements of self-determination, as well as having a prime focus on the individuals' experience in the journey of health promotion through participation in lifestyle interventions, has been identified as critically prominent. © 2023 The Authors. International Journal of Mental Health Nursing published by John Wiley & Sons Australia, Ltd
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