A Critical Window? Longitudinal Changes in Plasticity in Motor Cortex following Ischaemic Stroke

While spontaneous recovery occurs in most patients following stroke, it is often incomplete. Recovery seems to be mostly confined to the first 6 months. Data from animal models suggest there is a critical period of enhanced plasticity similar to that seen in early development. Evidence for such a critical period has not yet been established in humans. Repetitive transcranial magnetic stimulation is a suitable tool for measuring changes in plasticity in human motor cortex. However, its long-term test-retest reliability has not been widely studied. Experiment 1 19 younger (average 29.9 years) and 20 older (average 65.9 years) subjects had repeat sessions of spaced cTBS to motor cortex 6 months apart. Change in average MEPs over 30 minutes post spaced cTBS showed fair intraclass correlation across 6 months in young (0.458 CI [-0.406, 0.791]) and older (0.572 [95%CI -0.08, 0.83]) subjects. This is broadly equivalent to other forms of plasticity-modulating non-invasive brain stimulation. Experiment 2 29 subjects (average 68.2 years) had repeat spaced cTBS to contralesional motor cortex at 2, 4, 6 and 26 weeks following ischaemic stroke. There was a significant decrease in LTDlike plasticity across sessions (p<0.01). There was no change in resting motor threshold in either hemisphere and no change in intracortical excitability. Small vessel disease measured on MRI did not influence response to spaced cTBS. Experiment 3 To complement the expansion in clinical research examining the benefits of fluoxetine in enhancing post-stroke plasticity, 31 healthy volunteers (average age 26.3 years) received fluoxetine 20mg or placebo prior to undergoing spaced cTBS in a double-blind randomised cross-over trial. There was no effect of fluoxetine on response to cTBS (p=0.472). Conclusions There is a decrease in LTD-like plasticity in the 6 months following a stroke in humans. 20mg of fluoxetine had no effect on LTD-like plasticity in healthy subjects

Observation of cone and rod photoreceptors in normal subjects and patients using a new generation adaptive optics scanning laser ophthalmoscope.

We demonstrate the capability of a new generation adaptive optics scanning laser ophthalmoscope (AOSLO) to resolve cones and rods in normal subjects, and confirm our findings by comparing cone and rod spacing with published histology measurements. Cone and rod spacing measurements are also performed on AOSLO images from two different diseased eyes, one affected by achromatopsia and the other by acute zonal occult outer retinopathy (AZOOR). The potential of AOSLO technology in the study of these and other retinal diseases is illustrated

Logic Gates Using the Digilent Basys3

ENTC 3370 teaches students the basics of digital circuits. Until recently the students were taught using an analog device called a Protoboard. With the acquisition of the Digilent Basys3, a digital device, the class will begin to be taught using digital modeling techniques. This is a collection of lab activities designed to be used with the Basys3 within the class. The activities were designed in a way so that students with little programming knowledge could complete the tasks

Applying MCDA to weight indicators of seaport vulnerability to climate and extreme weather impacts for U.S. North Atlantic ports

This paper describes a case study applying multi-criteria decision analysis (MCDA) to weight indicators for assessing the exposure and sensitivity of seaports to climate and extreme weather impacts. Researchers employed the analytic hierarchy method (AHP) of MCDA to generate weights for a subset of expert-selected indicators of seaport exposure and sensitivity to climate and extreme weather. The indicators were selected from the results of a survey of port-experts who ranked candidate indicators by magnitude of perceived correlation with the three components of vulnerability; exposure, sensitivity, and adaptive capacity. As those port-expert respondents found significantly stronger correlation between candidate indicators and the exposure and sensitivity of a port than with a port’s adaptive capacity, this AHP exercise did not include indicators of adaptive capacity. The weighted indicators were aggregated to generate composite indices of seaport exposure and sensitivity to climate and extreme weather for 22 major ports in the North East United States. Rank order generated by AHP-weighted aggregation was compared to a subjective expert-ranking of ports by expert-perceived vulnerability to climate and extreme weather. For the sample of 22 ports, the AHP-generated ranking matched three of the top four most vulnerable ports as assessed subjectively by port-experts. These results suggest that a composite index based on open data weighted via MCDA may eventually prove useful as a data-driven tool for identifying outliers in terms of relative seaport vulnerabilities, however, improvements in the standardized reporting and sharing of port data will be required before such an indicator-based assessment method can prove decision-relevant

Expert evaluation of open-data indicators of seaport vulnerability to climate and extreme weather impacts for U.S. North Atlantic ports

When comparing vulnerabilities of multiple disparate systems, indicator-based vulnerability assessment (IBVA) methods can yield standardized metrics, allowing for high-level analysis to identify areas or systems of concern. Identification of indicators is often a first step in the development of coastal vulnerability indices (CVI). To advance IBVA for the seaport sector, researchers investigated the sufficiency of and elicited expert-evaluation of publicly available open-data to serve as indicators of climate and extreme-weather vulnerability for 22 major seaports in the North East United States, addressing the question: How sufficient is the current state of data reporting for and about the seaport sector to develop expert-supported vulnerability indicators for a regional sample of ports? Researchers developed a framework for expert-evaluation of candidate indicators that can be replicated to develop indicators in other sectors and for other purposes. Researchers first identified candidate indicators from the climate change vulnerability assessment (CCVA) and seaport-studies literature and vetted them for data-availability for the sample ports. Candidate indicators were then evaluated by experts via a mind-mapping exercise, and finally via a visual analogue scale (VAS) measurement instrument. Researchers developed a VAS instrument to elicit expert perception of the magnitude and direction of correlation between candidate indicators and each of the three dimensions of vulnerability that have become standard in the CCVA literature, e.g., exposure, sensitivity, and adaptive capacity. For candidate indicators selected from currently available open data sources, port-expert respondents found notably stronger correlation with the exposure and sensitivity of a port than with the adaptive capacity. Results suggest that more open reporting and sharing of port-specific data within the maritime transportation sector will be necessary before IBVA will become feasible for seaports

Seaport Climate Vulnerability Assessment at the Multi-Port Scale: A Review of Approaches

In the face of climate change impacts projected over the coming century, seaport decision makers have the responsibility to manage risks for a diverse array of stakeholders and enhance seaport resilience against climate and weather impacts. At the single port scale, decision makers such as port managers may consider the uninterrupted functioning of their port the number one priority. But, at the multi-port (regional or national) scale, policy-makers will need to prioritize competing port climate-adaptation needs in order to maximize the efficiency of limited physical and financial resources and maximize the resilience of the marine transportation system as a whole. This chapter provides an overview of a variety of approaches that set out to quantify various aspects of seaport vulnerability. It begins with discussion of the importance of a “multi-port” approach to complement the single case study approach more commonly applied to port assessments. It then addresses the components of climate vulnerability assessments and provides examples of a variety of approaches. Finally, it concludes with recommendations for next steps

Effect of sampling frequency on fractal fluctuations during treadmill walking

The temporal dynamics of stride-to-stride fluctuations in steady-state walking reveal important information about locomotor control and can be quantified using so-called fractal analyses, notably the detrended fluctuation analysis (DFA). Gait dynamics are often collected during treadmill walking using 3-D motion capture to identify gait events from kinematic data. The sampling frequency of motion capture systems may impact the precision of event detection and consequently impact the quantification of stride-to-stride variability. This study aimed i) to determine if collecting multiple walking trials with different sampling frequency affects DFA values of spatiotemporal parameters during treadmill walking, and ii) to determine the reliability of DFA values across downsampled conditions. Seventeen healthy young adults walked on a treadmill while their gait dynamics was captured using different sampling frequency (60, 120 and 240 Hz) in each condition. We also compared data from the highest sampling frequency to downsampled versions of itself. We applied DFA to the following time series: step length, time and speed, and stride length, time and speed. Reliability between experimental conditions and between downsampled conditions were measured with 1) intraclass correlation estimates and their 95% confident intervals, calculated based on a single-measurement, absolute-agreement, two-way mixed-effects model (ICC 3,1), and 2) Bland-Altman bias and limits of agreement. Both analyses revealed a poor reliability of DFA results between conditions using different sampling frequencies, but a relatively good reliability between original and downsampled spatiotemporal variables. Collectively, our results suggest that using sampling frequencies of 120 Hz or 240 Hz provide similar results, but that using 60 Hz may alter DFA values. We recommend that gait kinematics should be collected at around 120 Hz, which provides a compromise between event detection accuracy and processing time

A new sap beetle (Coleoptera: Nitidulidae) to the United States with a revised key to the Camptodes Erichson occurring in America north of Mexico

A new beetle to the United States, Camptodes communis Erichson, is briefly described below. A diagnosis from the other Camptodes known to occur in the United States is provided. An updated key to the Camptodes of the United States is given

Comparative Assessment of Seaport Vulnerabilities to Climate Change: Pilot Study for North Atlantic Medium and High-Use Seaports

The Third U.S. National Climate Assessment indicates that seaport infrastructure is already being damaged by sea level rise, heavy downpours, and extreme heat, and that these damages are expected to continue with continued climate change. To facilitate far-sighted planning for a climate-resilient Marine Transportation System (MTS) the United States Army Corps of Engineers (USACE), in collaboration with University of Rhode Island researchers in the Department of Marine Affairs, are piloting a climate-vulnerability indexing method that is driven by data and informed by expert knowledge. This research will contribute to a better understanding of the regional distribution of climate-vulnerability across North Atlantic ports in order to inform transportation resilience and climate-adaptation planning. This pilot study will investigate the climate vulnerabilities of seaports by applying expert elicitation methods to develop indicators of climate vulnerability for the 22 medium and high use ports of the USACE North Atlantic Division. In addition to refining a set of high-level indicators of seaport climate vulnerability, this research will employ expert elicitation methods to weight and aggregate selected indicators to determine the suitability of available data to differentiate ports within a region in terms of relative climate vulnerabilities. Results will serve as an entry point to inform MTS decision-makers in the USACE and other agencies about the nature of seaport climate change vulnerability, its components and determinants, the mechanisms through which a port is vulnerable, and the suitability of available data to serve as high-level indicators of seaport climate vulnerability. Ultimately, this research will support climate resilient national and regional transportation policy. Two published reports are associated with this data set: - Report Number: ERDC/CHL CR-19-2 Title: Measuring Climate and Extreme Weather Vulnerability to Inform Resilience, Report 1: A Pilot Study for North Atlantic Medium- and High-Use Maritime Freight Nodes By R. Duncan McIntosh, Elizabeth L. Mclean, and Austin Becker Link: http://dx.doi.org/10.21079/11681/35196 - Report Number: ERDC/CHL CR-19-3 Title: Measuring Climate and Extreme Weather Vulnerability to Inform Resilience, Report 2: Port Decision-Makers\u27 Barriers to Climate and Extreme Weather Adaption By Elizabeth L. Mclean and Austin Becker Link: http://dx.doi.org/10.21079/11681/3519

Relationship Between Foveal Cone Structure and Visual Acuity Measured With Adaptive Optics Scanning Laser Ophthalmoscopy in Retinal Degeneration.

PurposeTo evaluate foveal function in patients with inherited retinal degenerations (IRD) by measuring visual acuity (VA) after correction of higher-order aberrations.MethodsAdaptive optics scanning laser ophthalmoscopy (AOSLO) was used to image cones in 4 healthy subjects and 15 patients with IRD. The 840-nm scanning laser delivered an "E" optotype to measure AOSLO-mediated VA (AOSLO-VA). Cone spacing was measured at the preferred retinal locus by two independent graders and the percentage of cones below the average density of 47 age-similar healthy subjects was computed. Cone spacing was correlated with best-corrected VA measured with the Early Treatment of Diabetic Retinopathy Study protocol (ETDRS-VA), AOSLO-VA, and foveal sensitivity.ResultsETDRS-VA significantly correlated with AOSLO-VA (ρ = 0.79, 95% confidence interval [CI] 0.5-0.9). Cone spacing correlated with AOSLO-VA (ρ = 0.54, 95% CI 0.02-0.7), and negatively correlated with ETDRS letters read (ρ = -0.64, 95% CI -0.8 to -0.2). AOSLO-VA remained ≥20/20 until cones decreased to 40.2% (CI 31.1-45.5) below normal. Similarly, ETDRS-VA remained ≥20/20 until cones were 42.0% (95% CI 36.5-46.1) below normal. Cone spacing z scores negatively correlated with foveal sensitivity (ρ = -0.79, 95% CI -0.9 to -0.4) and foveal sensitivity was ≥35 dB until cones were 43.1% (95% CI 39.3-46.6) below average.ConclusionsVA and foveal cone spacing were weakly correlated until cones were reduced by 40% to 43% below normal. The relationship suggests that VA is an insensitive measure of foveal cone survival; cone spacing may be a more sensitive measure of cone loss