2,639 research outputs found
Rent-Seeking in Noxious Weed Regulations: Evidence from US States
Many non-native insect, disease, and weed pests of food, fiber, and nursery crops pose threats to the U.S. environment, agricultural production, and exports. In this study we focus on regulations controlling the spread of noxious weeds, especially the regulatory differences among US states and investigate the determinants of such regulations. With a simple game-theoretic framework, we derive cross-state regulatory congruence as a function of ecological and agronomic characteristics and stakeholder lobbying through political contributions. Empirical results suggest ecological and agronomic dissimilarities drive large cross-state differences in noxious weed regulation across states. However, evidence of stakeholder interests in shaping these regulations is found to be statistically significant. In particular, the seed industry appears to favor more uniform regulations among US states.Environmental Economics and Policy,
Outcomes of positive airway pressure for sleep apnea-reply
Abstract not availableR. McEvoy, Z. Zhou, B. Nea
Simultaneous intracranial EEG and fMRI of interictal epileptic discharges in humans
Simultaneous scalp EEGâfMRI measurements allow the study of epileptic networks and more generally, of the coupling between neuronal activity and haemodynamic changes in the brain. Intracranial EEG (icEEG) has greater sensitivity and spatial specificity than scalp EEG but limited spatial sampling. We performed simultaneous icEEG and functional MRI recordings in epileptic patients to study the haemodynamic correlates of intracranial interictal epileptic discharges (IED).
Two patients undergoing icEEG with subdural and depth electrodes as part of the presurgical assessment of their pharmaco-resistant epilepsy participated in the study. They were scanned on a 1.5 T MR scanner following a strict safety protocol. Simultaneous recordings of fMRI and icEEG were obtained at rest. IED were subsequently visually identified on icEEG and their fMRI correlates were mapped using a general linear model (GLM).
On scalp EEGâfMRI recordings performed prior to the implantation, no IED were detected. icEEGâfMRI was well tolerated and no adverse health effect was observed. intra-MR icEEG was comparable to that obtained outside the scanner. In both cases, significant haemodynamic changes were revealed in relation to IED, both close to the most active electrode contacts and at distant sites. In one case, results showed an epileptic network including regions that could not be sampled by icEEG, in agreement with findings from magneto-encephalography, offering some explanation for the persistence of seizures after surgery.
Hence, icEEGâfMRI allows the study of whole-brain human epileptic networks with unprecedented sensitivity and specificity. This could help improve our understanding of epileptic networks with possible implications for epilepsy surgery
Neck atonia with a focal stimulation-induced seizure arising from the SMA: pathophysiological considerations.
A 28-year-old patient with pharmacoresistant non-lesional right frontal epilepsy underwent extra-operative intracranial EEG recordings and electrical cortical stimulation (ECS) to map eloquent cortex. Right supplementary motor area (SMA) ECS induced a brief seizure with habitual symptoms involving neck tingling followed by asymmetric tonic posturing. An additional feature was neck atonia. During atonia and sensory aura, discharges were seen in the mesial frontal electrodes and precentral gyrus. Besides motor signs, atonia, although rare and not described in the neck muscles, and sensations have been reported with SMA stimulation. The mechanisms underlying neck atonia in seizures arising from the SMA can be explained by supplementary negative motor area (SNMA) - though this was not mapped in electrodes overlying the ictal onset zone in our patient - or primary sensorimotor cortex activation through rapid propagation. Given the broad spectrum of signs elicited by SMA stimulation and rapid spread of seizures arising from the SMA, caution should be taken to not diagnose these as non-epileptic, as had previously occurred in this patient
The Benefits of Fit-for-Purpose Land Administration for Urban Community Resilience in a Time of Climate Change and COVID-19 Pandemic
The major global pressures of rapid urbanization and urban growth are being compounded by climate impacts, resulting in increased vulnerability for urban dwellers, with these vulnerabilities exacerbated during the COVID-19 pandemic. Much of this is concentrated in urban and peri-urban areas where urban development spreads into hazard-prone areas. Often, this development is dominated by poor-quality homes in informal settlements or slums with poor tenure security. Lessons from a resilience-building project in the Pacific shows that a fit-for-purpose (FFP) approach to land administration can provide solutions by increasing the number of households with security of tenure, and consequently, improving resilience outcomes as informal settlements grow. This paper specifically discusses the influence of FFP land administration on reducing vulnerabilities to external shocks, such as climate change and COVID-19. It proposes ways to be better manage urban growth through the responsible governance of land tenure rights and more effective land-use planning to improve resilience to multiple shocks and stresses, hence, delivering improved access to safe land and shelter. Land administration systems can contribute to enhanced resilience to the shocks of climate extremes and pandemics by improving tenure security and enhancing land-use planning controls. It is argued that climate change adaptation and disaster risk reduction need to be better mainstreamed into two major elements of land governance: (i) securing and safeguarding of land rights, and (ii) planning and control of land use
UWB Microwave Imaging for Inclusions Detection: Methodology for Comparing Artefact Removal Algorithms
An investigation is presented on Artefact Removal Methods for Ultra-Wideband (UWB) Microwave Imaging. Simulations have been done representing UWB signals transmitted onto a cylindrical head-mimicking phantom containing an inclusion having dielectric properties imitating an haemorrhagic stroke. The ideal image is constructed by applying a Huygensâ Principle based imaging algorithm to the difference between the electric field outside the cylinder with an inclusion and the electric field outside the same cylinder with no inclusion. Eight different artefact removal methods are then applied, with the inclusion positioned at \u1d70b and â\u1d70b/4 radians, respectively. The ideal image is then used as a reference image to compare the artefact removal methods employing a novel Image Quality Index, calculated using a weighted combination of image quality metrics. The Summed Symmetric Differential method performed very well in our simulations
Free space operating microwave imaging device for bone lesion detection: a phantom investigation
In this letter, a phantom validation of a low complexity microwave imaging device operating in free space in the 1-6.5 GHz frequency band is presented. The device, initially constructed for breast cancer detection, measures the scattered signals in a multi-bistatic fashion and employs an imaging procedure based on Huygens principle. Detection has been achieved
in both bone fracture lesion and bone marrow lesion scenarios using the superimposition of five doublet transmitting positions, after applying the rotation subtraction artefact removal method. A resolution of 5 mm and a signal to clutter ratio (3.35 in linear scale) are achieved confirming the advantage of employing multiple transmitting positions on increased detection capability
Weather, Timing, and Promotions in Minor League Baseball: An Examination of Attendance in the International League
Understanding the different factors that impact attendance at sporting events is a timely and relevant topic for researchers and practitioners alike. The present study examines the effects of different types of promotions, weather, and selected temporal elements on attendance in Minor League Baseball. Using data for teams participating in the International League during the 2010 season, results from a multiple regression analysis revealed that special events, promotional giveaways, and non-workdays have a positive impact on attendance; while suboptimal weather conditions have a negative impact. These findings contribute to our understanding of the factors that impact attendance in professional baseball and hold useful implications for future research and managerial practice
Virtual patients: an effective educational intervention to improve paediatric basic specialist trainee education in the management of suspected child abuse?
Child abuse is a particularly difficult subject to teach at both undergraduate and postgraduate level. Most doctors are dissatisfied with their training in child abuse recognition and management. We developed an interactive video based Virtual Patient to provide formal training for paediatric Basic Specialist Trainees in the recognition of suspected child abuse. The Virtual Patient case revolves around the management of suspected physical abuse in a seven month old child, who initially presents to the Emergency Department with viral upper respiratory tract symptoms. This Virtual Patient was used to facilitate a case discussion with Basic Specialist Trainees. A questionnaire was developed to determine their perception of the value of the Virtual Patient as an educational tool. Twenty five Basic Specialist Trainees completed the questionnaire. Upon completion of the case, 23/25 (92%) participants reported greater self confidence in their ability to recognize cases of suspected child abuse and 24/25 (96%) of participants reported greater self confidence in their ability to report cases of suspected child abuse. Basic Specialist Trainees perceived the Virtual Patient to be a useful educational tool. Virtual Patients may have a role to play in enhancing postgraduate training in the recognition of suspected child abuse
Reversed Procrastination by Focal Disruption of Medial Frontal Cortex.
An enduring puzzle in the neuroscience of voluntary action is the origin of the remarkably wide dispersion of the reaction time distribution, an interval far greater than is explained by synaptic or signal transductive noise [1, 2]. That we are able to change our planned actions-a key criterion of volition [3]-so close to the time of their onset implies decision-making must reach deep into the execution of action itself [4-6]. It has been influentially suggested the reaction time distribution therefore reflects deliberate neural procrastination [7], giving alternative response tendencies sufficient time for fair competition in pursuing a decision threshold that determines which one is behaviorally manifest: a race model, where action selection and execution are closely interrelated [8-11]. Although the medial frontal cortex exhibits a sensitivity to reaction time on functional imaging that is consistent with such a mechanism [12-14], direct evidence from disruptive studies has hitherto been lacking. If movement-generating and movement-delaying neural substrates are closely co-localized here, a large-scale lesion will inevitably mask any acceleration, for the movement itself could be disrupted. Circumventing this problem, here we observed focal intracranial electrical disruption of the medial frontal wall in the context of the pre-surgical evaluation of two patients with epilepsy temporarily reversing such hypothesized procrastination. Effector-specific behavioral acceleration, time-locked to the period of electrical disruption, occurred exclusively at a specific locus at the ventral border of the pre-supplementary motor area. A cardinal prediction of race models of voluntary action is thereby substantiated in the human brain
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