272 research outputs found

    The African American Male Initiative at the University of Louisville

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    Following a year of data gathering and planning during the 2010-2011 academic year, the University of Louisville launched the African American Male Initiative (AAMI) in the fall 2011 semester. The AAMI was designed using national best practices and current research findings as it relates to supporting African American male undergraduates. Now at the end of its first year, this practitioner’s brief provides an overview of the AAMI structure, design, and implementation

    Manifesting Unobtainable Secrets: Threshold Elliptic Curve Key Generation using Nested Shamir Secret Sharing

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    We present a mechanism to manifest unobtainable secrets using a nested Shamir secret sharing scheme to create public/private key pairs for elliptic curves. A threshold secret sharing scheme can be used as a decentralised trust mechanism with applications in identity validation, message decryption, and agreement empowerment. Decentralising trust means that there is no single point vulnerability which could enable compromise of a system. Our primary interest is in twisted Edwards curves as used in EdDSA, and the related Diffie-Hellman key-exchange algorithms. The key generation is also decentralised, so can be used as a decentralised secret RNG suitable for use in other algorithms. The algorithms presented could be used to fill a ``[TBS]'' in the draft IETF specification ``Threshold modes in elliptic curves'' published in 2020 and updated in 2022

    Differential modulation of [gamma]-aminobutyric acid receptors by caprolactam derivatives with central nervous system depressant on convulsant activity

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    The effects of a series of caprolactam derivatives with central depressant, convulsant or muscle relaxant activity were investigated upon [gamma]-aminobutyric acid (GABA) receptor-ionophore binding to rat brain membranes using [3H]GABA, [3H]muscimol and [35S]-tert.-butylbicyclophophorothionate ([35S]TBPS) as ligands, and GABA resonses in mouse spinal cord neurones in dissociated cell culture. Some caprolactams produced a picrotoxin-like chloride-dependent partial inhibition of muscimol binding and were potent inhibitors of TBPS binding. One compound that was further investigated (4,4,6,6,-tetramethylhexahydro-2H-azepin-2-one), inhibited GABA responses and increased the frequency of paroxysmal depolarizations in cultured neurones. Other caprolactams enhanced muscimol binding and were relatively weak inhibitors of TBPS binding, and one (3,3-diallyl-6,6-dimethylhexahydro-2H-azepin-2,4-dione) was shown to enhance GABA responses and produced quiescence of activity in cultured neurones. There was a direct correaltion between caprolactam effects on muscimol binding in the presence of chloride ions and their effects on TBPS binding suggesting a similar site of action for the caprolactams influencing the binding of these two ligands. For the two classes of caprolactams, with respect to inhibition or enhancement of muscimol binding, there appeared to be a relationship between in vitro effects and their convulsant or depressant activity in mice. Caprolactams may be useful low molecular weight probes for the study of GABA receptor-ionophore complexes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25708/1/0000262.pd

    Anticonvulsant drug actions on neurons in cell culture

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    Two actions of clinically used antiepileptic drugs have been studied using mouse neurons in primary dissociated cell culture. The antiepileptic drugs phenytoin, carbamazepine and valproic acid were demonstrated to limit sustained high frequency repetitive firing of action potentials at free serum concentratons that are achieved in patients being treated for epilepsy. Furthermore, an active metabolite of carbamazepine also limited sustained high frequency repetitive firing while inactive metabolites of phenytoin and carbamazepine did not limit sustained high frequency repetitive firing. Phenobarbital and clinically used benzodiazepines limited sustained high frequency repetitive firing of action potentials, but only at concentrations achieved during the treatment of generalized tonic-clonic status epilepticus. Ethosuximide did not limit sustained high frequency repetitive firing even at concentrations four times those achieved in the serum of patients treated for generalized absence seizures. Phenobarbital and clinically used benzodiazepines enhanced postsynaptic GABA responses at concentrations achieved free in the serum during treatment of generalized tonic-clonic or generalized absence seizures. However, phenytoin, carbamazepine, valproic acid and ethosuximide did not modify postsynaptic GABA responses at therapeutic free serum concentrations. These results suggest that the ability of antiepileptic drugs to block generalized tonicclonic seizures and generalized tonic-clonic status epilepticus may be related to their ability to block high frequency repetitive firing of neurons. The mechanism underlying blockade of myoclonic seizures may be related to the ability of antiepileptic drugs to enhance GABAergic synaptic transmission. The mechanism underlying management of generalized absence seizures remains unclear.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41657/1/702_2005_Article_BF01243417.pd

    Improving teaching: Enhancing ways of being university teachers

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    My aim in this paper is to theorize my teaching in a course for experienced university teachers, in a context of increased attention to such courses. My focus in the course is transforming and enhancing ways of being university teachers, through integrating knowing, acting and being. In other words, epistemology is not seen as an end in itself, but rather it is in the service of ontology. In the paper, I explore and illustrate how this focus on ontology is enacted in the course

    Supporting open innovation with the use of a balanced scorecard approach: a study on deep smarts and effective knowledge transfer to SMEs

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    This study aims to develop the theory of knowledge management and organizational performance within a small and medium enterprise (SME) context using action research (AR) involving a higher education institution (HEI) and an SME. The vehicle for the knowledge exchange was Knowledge Transfer Partnerships (KTPs), the United Kingdom’s primary mechanism for delivering government funded knowledge transfer to small and medium enterprises (SMEs). KTPs facilitate knowledge exchange from HEIs to SMEs via the recruitment of a graduate plus an academic supervisor from the partnering HEI. The AR study was an award-winning KTP and the project deliverable included the implementation of a balanced scorecard for the SME to improve organizational performance. The transfer of knowledge was subsequently fed-back into the university in order to develop a performance framework for measuring the effectiveness of KTP research within the HEI in order to share knowledge and improve effective for other KTP projects

    A conceptual model for action and design research

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    Organizational research has a pattern of special characteristics which make a clear distinction from other research paradigms. When using these approaches – based on Action and Design – the Interpretivist, Constructivist, and Participatory perspectives dominate. They have already proven to have strong foundations, which turn these paradigmatic approaches into effective ways for getting knowledge, doing things, and promoting change within organizational settings. It combines the traditional scientific, engineering, and organization development approaches, depicting how an organization can, simultaneously, solve multidimensional problems and produce actionable knowledge, effective change and useful artifacts. It has been developed using a Design Science Research approach, tested in a major organizational change program (Henriques, 2015; Henriques & ONeill, 2014), and successfully used to teach research methods essentials to Master and DBA students.info:eu-repo/semantics/publishedVersio

    Ethosuximide modifies network excitability in the rat entorhinal cortex via an increase in GABA release

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    Ethosuximide is the drug of choice for treating generalized absence seizures, but its mechanism of action is still a matter of debate. It has long been thought to act by disrupting a thalamic focus via blockade of T-type channels and, thus, generation of spike-wave activity in thalamocortical pathways. However, there is now good evidence that generalized absence seizures may be initiated at a cortical focus and that ethosuximide may target this focus. In the present study we have looked at the effect ethosuximide on glutamate and GABA release at synapses in the rat entorhinal cortex in vitro, using two experimental approaches. Whole-cell patch-clamp studies revealed an increase in spontaneous GABA release by ethosuximide concurrent with no change in glutamate release. This was reflected in studies that estimated global background inhibition and excitation from intracellularly recorded membrane potential fluctuations, where there was a substantial rise in the ratio of network inhibition to excitation, and a concurrent decrease in excitability of neurones embedded in this network. These studies suggest that, in addition to well-characterised effects on ion channels, ethosuximide may directly elevate synaptic inhibition in the cortex and that this could contribute to its anti-absence effects. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'
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