1,044 research outputs found

    Benefit Corporations in the United States and Community Interest Companies in the United Kingdom: Does Social Enterprise Actually Work?

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    Abstract: Social enterprise is becoming an increasingly popular and profitable venture in the United States and around the world today. In the United States, the benefit corporation model leads this movement, offering incorporating companies a positive image, a platform to build consumer trust, and the flexibility to pursue social good. However, though the benefit corporation form comes with the aforementioned branding advantages, states’ benefit corporation laws as they currently exist generally lack adequate oversight mechanisms. Consequently, third parties like B Lab play an important role as the primary enforcement entities ensuring that benefit corporations adhere to their stated purposes. The U.S. benefit corporation could gain from a close analysis of the U.K. community interest corporation, as the latter model places greater emphasis on impacts to local community and operates under strict government oversight. Simultaneously, U.K. community interest corporations could enhance their efficacy by incorporating benefit corporations’ emphasis on global branding. By gaining from the other’s strengths, U.S. benefit corporations and U.K. community interest corporations could gain considerable influence, not only as profitable and community-centered businesses but also as global leaders in today’s growing social enterprise movement

    Benefit Corporations in the United States and Community Interest Companies in the United Kingdom: Does Social Enterprise Actually Work?

    Get PDF
    Abstract: Social enterprise is becoming an increasingly popular and profitable venture in the United States and around the world today. In the United States, the benefit corporation model leads this movement, offering incorporating companies a positive image, a platform to build consumer trust, and the flexibility to pursue social good. However, though the benefit corporation form comes with the aforementioned branding advantages, states’ benefit corporation laws as they currently exist generally lack adequate oversight mechanisms. Consequently, third parties like B Lab play an important role as the primary enforcement entities ensuring that benefit corporations adhere to their stated purposes. The U.S. benefit corporation could gain from a close analysis of the U.K. community interest corporation, as the latter model places greater emphasis on impacts to local community and operates under strict government oversight. Simultaneously, U.K. community interest corporations could enhance their efficacy by incorporating benefit corporations’ emphasis on global branding. By gaining from the other’s strengths, U.S. benefit corporations and U.K. community interest corporations could gain considerable influence, not only as profitable and community-centered businesses but also as global leaders in today’s growing social enterprise movement

    The Changing Landscape of Carrier Screening: Expanding Technology and Options?

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    Chaotic Advection for Enhanced Reagent Mixing

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    In situ remediation techniques commonly involve the injection of a reagent into the subsurface to create a zone in which biological and/or chemical reactions lead to mass destruction of contaminants. In these injection-driven remedial systems, the delivery of reagent solutions is a key requirement for success; however, the design of an effective delivery system remains a significant challenge. Subsurface heterogeneities create preferential flow pathways over a range of spatial scales that produce an uneven distribution of the injected fluid. For conventional injection methods that use vertical wells, the injected reagent will follow the path of least resistance from the wellbore into the porous medium, and the distribution will be greater in areas of higher hydraulic conductivity (K) with potential to bypass adjacent regions of lower K. In these lower K zones, molecular diffusion is possibly the primary transport mechanism responsible to bring the injected reagent into contact with the contaminant; however, diffusion is a slow process and contributes to inefficient mixing. Chaotic advection refers to the generation of small-scale structures from the repeated stretching and folding of fluid elements in a laminar flow regime. The small-scale structures produced by this chaotic stirring create fluid elements that are stretched out into long, thin filaments with a length scale sufficiently small for diffusion to promote efficient mixing. It has been theorized that chaotic advection has the potential to overcome preferential flow paths and enhance mixing. One configuration which has been theoretically and experimentally used to invoke chaotic advection in porous media is termed a rotated potential mixing (RPM) flow. An RPM flow system involves periodically re-oriented dipole flow through the transient switching of pressures at a series of radial wells. If chaotic advection can be invoked and controlled in situ, reagent delivery and treatment effectiveness may be significantly improved. Thus, the primary objective of this research effort was to improve our understanding of chaotic advection and its implications on reagent delivery. To investigate if chaotic advection can be engineered in a natural aquifer system using RPM flow, and to assess the consequent impact on the spatial distribution of a conservative tracer, a series of field-scale experiments were completed. Investigations were performed in an experimental gate at the University of Waterloo Groundwater Research Facility at the Canadian Forces Base in Borden, ON, Canada. Each experiment involved the injection of a pre-determined tracer volume in the center of a circular array of injection/extraction wells, followed by either mixing using an RPM flow protocol to invoke chaotic advection, or by natural processes (advection and diffusion) as the control. Hydraulic data and tracer breakthrough responses were used to investigate the presence of chaotic advection. Various quantitative metrics (e.g., integrated volume under the three-dimensional contours of tracer concentration data, variance of tracer concentrations, spatial concentration gradients, and the first two spatial moments of the tracer concentration distribution) were adopted to assess field-scale evidence of mixing. The results from these various quantitative metrics indicated the presence of chaotic advection which led to improved lateral spreading and enhanced mixing to establish uniform concentrations across the monitoring network. The findings demonstrated that an RPM flow system is a viable and efficient approach to enhance reagent mixing. Prior to the implementation of a chaotic advection system, determination of the RPM flow protocol will likely require a numerical model for adequate representation of groundwater flow undergoing periodically re-oriented dipole pumping. It is expected that the K field will control the behavior of the system. To capture K heterogeneities in a target treatment zone, hydraulic head responses from multiple independent dipole pumping tests were used in a three-dimensional steady-state hydraulic tomography (SSHT) analysis. For validation of the estimated K field from SSHT analysis, forward simulations of steady-state and transient groundwater flow were performed. The impact of using this K field on the spatial distribution of a hypothetical reagent in the target treatment zone was then investigated using particle tracking methods. The findings demonstrated that the same well system used to invoke chaotic advection is a viable site characterization tool to delineate the variability of the K field using SSHT analysis. Furthermore, the use of this K field in a particle tracking engine led to more spatially and densely distributed particle trajectories indicative of enhanced reagent mixing than those produced by an effective parameter approach (i.e., a single value of K assigned across the entire spatial domain). These results suggested that using K information applicable to a specific area of interest leads to a more effective design of an RPM flow system that can enhance reagent mixing. Simulations were performed in two dimensions to investigate whether a conventional modeling method can be used capture the transport behavior of a conservative reagent in the presence of chaotic advection, and to explore the impact of specific engineering controls associated with an RPM flow system on reagent mixing. The multiple lines of evidence assembled in this study demonstrated that this modeling approach captured the key features of the expected transport behavior reported in other studies of chaotic advection over a range of scales (e.g., theory, laboratory and field). Visual observations from the reagent distribution produced, and the results from the quantitative metrics of mixing behavior highlighted the different responses that are possible by the various combinations of RPM flow parameters explored. The findings demonstrated the importance of combining theoretical considerations with practical limitations when designing an RPM flow system. The flow rate and pumping duration were identified as key parameters of an RPM flow system that have direct consequences on the degree of reagent spreading and mixing. In addition, the use of the same RPM flow protocol in a heterogeneous K field led to significantly greater degree of reagent mixing than in a homogeneous K setting. These findings represent a significant step towards the development of a modeling approach for the design of an effective RPM flow system that can support field implementation of chaotic advection and promote enhanced reagent mixing. The tracer experiments described in this proof-of-concept study are significant since these investigations are the first field-scale efforts to extend on the established theoretical underpinnings and observations from bench-scale experiments of chaotic advection. Multiple lines of evidence assembled in this research effort demonstrate that chaotic advection can be engineered at the field scale using an RPM flow system. These findings also provide comprehensive information about chaotic advection as an approach to enhance reagent mixing in a natural aquifer system. The suite of quantitative metrics and numerical efforts presented in this study provide various tools for the design of an RPM flow system, and the subsequent data interpretation to support field applications of chaotic advection. Collectively, the combination of experimental and computational efforts presented in this study provide comprehensive insights into an effective design and implementation of an RPM flow system to generate chaotic advection for enhanced reagent mixing

    A Pilot Survey on the Licensing of DNA Inventions

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    Despite ethical concerns about gene patents, virtually no empirical evidence exists to support claims about either positive or negative effects, and extremely little is known about the intellectual property protection strategies of firms and universities. This article discusses the results of a pilot study to examine patenting and licensing philosophies, policies, and practices of different types of institutions and to describe the contractual conditions for licensing DNA sequence inventions

    The Impact of Drug and Gene Interaction on the Antipsychotic Medication for Schizophrenia

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    Objective: Schizophrenia, a neuropsychiatric disorder, is known to be neurodevelopmentally progressive. Due to the extensive interindividual variability found in the responses of patients, management of schizophrenia has proven to be challenging. This interindividual variability to treatment could be justified by the variation of the enzymes in charge of metabolizing medications, especially those associated with cytochrome P450. Since genetic factors influence the phenotypic responses to drugs, researchers are involved in identifying schizophrenic genetic factors, which could impact responses and severe effects for commonly known neuroleptic drugs known as pharmacogenetics. In order to predict drug response at the personal level, genetic variants that determine drug effects need to be identified. Methods: We have chosen to investigate gene targets for risperidone and clozapine, two commonly administered drugs for the treatment of schizophrenia. The aim of this review is to contribute in the understanding of genetic influences on drug responses of risperidone and clozapine in schizophrenia. We reviewed original primary research articles, meta-analysis, and review publications on drug and gene interaction on the treatment of schizophrenia. Our main findings focused on schizophrenia, pharmacogenetics and cytochrome P450. Results and conclusion: After filtering our results to human species and English language, a total of 45 scientific articles were used for this review. A promising direction for future research in schizophrenia treatment lies behind the identification of the specific genetic contributors that affect drug response

    Children’s particulate matter exposure characterization as part of the new hampshire birth cohort study

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    As part of the New Hampshire Birth Cohort Study, children 3 to 5 years of age participated in a personal PM2.5 exposure study. This paper characterizes the personal PM2.5 exposure and protocol compliance measured with a wearable sensor. The MicroPEM™ collected personal continuous and integrated measures of PM2.5 exposure and compliance data on 272 children. PM2.5, black carbon (BC), and brown carbon tobacco smoke (BrC-ETS) exposure was measured from the filters. We per-formed a multivariate analysis of woodstove presence and other factors that influenced PM2.5, BC, and BrC exposures. We collected valid exposure data from 258 of the 272 participants (95%). Children wore the MicroPEM for an average of 46% of the 72-h period, and over 80% for a 2-day, 1-night period (with sleep hours counted as non-compliance for this study). Elevated PM2.5 exposures oc-curred in the morning, evening, and overnight. Median PM2.5, BC, and BrC-ETS concentrations were 8.1 μg/m3, 3.6 μg/m3, and 2.4 μg/m3. The combined BC and BrC-ETS mass comprised 72% of the PM2.5. Woodstove presence, hours used per day, and the primary heating source were associated with the children’s PM2.5 exposure and air filters were associated with reduced PM2.5 concentrations. Our findings suggest that woodstove smoke contributed significantly to this cohort’s PM2.5 expo-sure. The high sample validity and compliance rate demonstrated that the MicroPEM can be worn by young children in epidemiologic studies to measure their PM2.5 exposure, inform interventions to reduce the exposures, and improve children’s health
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