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Comparison of transabdominal ultrasound and electromagnetic transponders for prostate localization.
The aim of this study is to compare two methodologies of prostate localization in a large cohort of patients. Daily prostate localization using B-mode ultrasound has been performed at the Nebraska Medical Center since 2000. More recently, a technology using electromagnetic transponders implanted within the prostate was introduced into our clinic (Calypso(R)). With each technology, patients were localized initially using skin marks. Localization error distributions were determined from offsets between the initial setup positions and those determined by ultrasound or Calypso. Ultrasound localization data was summarized from 16619 imaging sessions spanning 7 years; Calypso localization data consists of 1524 fractions in 41 prostate patients treated in the course of a clinical trial at five institutions and 640 localizations from the first 16 patients treated with our clinical system. Ultrasound and Calypso patients treated between March and September 2007 at the Nebraska Medical Center were analyzed and compared, allowing a single institutional comparison of the two technologies. In this group of patients, the isocenter determined by ultrasound-based localization is on average 5.3 mm posterior to that determined by Calypso, while the systematic and random errors and PTV margins calculated from the ultrasound localizations were 3 - 4 times smaller than those calculated from the Calypso localizations. Our study finds that there are systematic differences between Calypso and ultrasound for prostate localization
Preparation for action: Psychophysiological activity preceding a motor skill as a function of expertise, performance outcome, and psychological pressure
Knowledge of the psychophysiological responses that characterize optimal motor performance is required to inform biofeedback interventions. This experiment compared cortical, cardiac, muscular, and kinematic activity in 10 experts and 10 novices as they performed golf putts in low- and high-pressure conditions. Results revealed that in the final seconds preceding movement, experts displayed a greater reduction in heart rate and EEG theta, high-alpha, and beta power, when compared to novices. EEG high-alpha power also predicted success, with participants producing less high-alpha power in the seconds preceding putts that were holed compared to those that were missed. Increased pressure had little impact on psychophysiological activity. It was concluded that greater reductions in EEG high-alpha power during preparation for action reflect more resources being devoted to response programming, and could underlie successful accuracy-based performance
Introduction
What are the strategies, modalities and aspirations of island-based, stateless nationalist and regionalist parties in the twenty-first century? Political independence is now easier to achieve, even by the smallest of territories; yet, it is not so likely to be pursued with any vigour by the world's various persisting sub-national (and mainly island) jurisdictions. Theirs is a pursuit of different expressions of sub-national autonomy, stopping short of independence. And yet, a number of independence referenda are scheduled, including one looming in Scotland in autumn 2014
Premovement high-alpha power is modulated by previous movement errors: Indirect evidence to endorse high-alpha power as a marker of resource allocation during motor programming
Previous electroencephalographic studies have identified premovement high-alpha power as a predictor of movement accuracy; less frontal-central high-alpha power is associated with accurate movements (e.g., holed golf putts), and could reflect more cognitive resources being allocated to response programming. The present experiment tested this interpretation. Ten expert and ten novice golfers completed 120 putts while high-alpha power was recorded and analyzed as a function of whether the previous putt was holed (i.e., a correct response) or missed (i.e., an error). Existing evidence indicates that more resources are allocated to response programming following errors. We observed less premovement high-alpha power following errors, especially in experts. Our findings provide indirect evidence that high-alpha power is an inverse marker of the amount of resources allocated to motor response programmin
Effects of ingesting JavaFit Energy Extreme functional coffee on aerobic and anaerobic fitness markers in recreationally-active coffee consumers
The purpose of this study was to examine the effects of ingesting JavaFit™ Energy Extreme (JEE) on aerobic and anaerobic performance measures in recreationally-active male and female coffee drinkers. Five male (27.6 ± 4.2 yrs, 93.2 ± 11.7 kg, 181.6 ± 6.9 cm) and five female (29 ± 4.6 yrs, 61.5 ± 9.2 kg, 167.6 ± 6.9 cm) regular coffee drinkers (i.e., 223.9 ± 62.7 mg·d(-1 )of caffeine) participated in this study. In a cross-over, randomized design, participants performed a baseline (BASELINE) graded treadmill test (GXT) for peak VO(2 )assessment and a Wingate test for peak power. Approximately 3–4 d following BASELINE testing, participants returned to the lab for the first trial and ingested 354 ml of either JEE or decaffeinated coffee (DECAF), after which they performed a GXT and Wingate test. Criterion measures during the GXT included an assessment of peakVO(2 )at maximal exercise, as well as VO(2 )at 3 minutes and 10 minutes post-exercise. Additionally, time-to-exhaustion (TTE), maximal RPE, mean heart rate (HR), mean systolic pressure (SBP), and mean diastolic blood pressure (DBP) were measured during each condition. Criterion measures for the Wingate included mean HR, SBP, DBP, peak power, and time to peak power (TTP). Participants then returned to the lab approximately one week later to perform the second trial under the same conditions as the first, except consuming the remaining coffee. Data were analyzed using a one way ANOVA (p < 0.05). Our results indicate that JEE significantly increased VO(2 )at 3 minutes post-exercise when compared to BASELINE (p = 0.04) and DECAF (p = 0.02) values, which may be beneficial in enhancing post-exercise fat metabolism
Genome-wide RNA sequencing of ocular fibroblasts from glaucomatous and normal eyes: Implications for glaucoma management
Primary open angle glaucoma is a leading cause of visual impairment and blindness which is commonly treated with drugs or laser but may require surgery. Tenon’s ocular fibroblasts are involved in wound-healing after glaucoma filtration surgery and may compromise a favourable outcome of glaucoma surgery by contributing to fibrosis. To investigate changes in gene expression and key pathways contributing to the glaucomatous state we performed genome-wide RNA sequencing. Human Tenon’s ocular fibroblasts were cultured from normal and glaucomatous human donors undergoing eye surgery (n = 12). mRNA was extracted and RNA-Seq performed on the Illumina platform. Differentially expressed genes were identified using a bioinformatics pipeline consisting of FastQC, STAR, FeatureCounts and edgeR. Changes in biological functions and pathways were determined using Enrichr and clustered using Cytoscape. A total of 5817 genes were differentially expressed between Tenon’s ocular fibroblasts from normal versus glaucomatous eyes. Enrichment analysis showed 787 significantly different biological functions and pathways which were clustered into 176 clusters. Tenon’s ocular fibroblasts from glaucomatous eyes showed signs of fibrosis with fibroblast to myofibroblast transdifferentiation and associated changes in mitochondrial fission, remodeling of the extracellular matrix, proliferation, unfolded protein response, inflammation and apoptosis which may relate to the pathogenesis of glaucoma or the detrimental effects of topical glaucoma therapies. Altered gene expression in glaucomatous Tenon’s ocular fibroblasts may contribute to an unfavourable outcome of glaucoma filtration surgery. This work presents a genome-wide transcriptome of glaucomatous versus normal Tenon’s ocular fibroblasts which may identify genes or pathways of therapeutic value to improve surgical outcomes
Multi-vehicle Control in a Strong Flowfield with Application to Hurricane Sampling
A major obstacle to path-planning and formation-control algorithms in multi-vehicle systems are strong flows in which the ambient flow speed is greater than the vehicle speed relative to the flow. This challenge is espe-cially pertinent in the application of unmanned aircraft used for collecting targeted observations in a hurricane. The presence of such a flowfield may inhibit a vehicle from making forward progress relative to a ground-fixed frame, thus limiting the directions in which it can travel. Using a self-propelled particle model in which each particle moves at constant speed relative to the flow, this paper presents results for motion coordination in a strong, known flowfield. We present the particle model with respect to inertial and rotating reference frames and provide for each case a set of con-ditions on the flowfield that ensure trajectory feasibility. Results from the Lyapunov-based design of decentralized control algorithms are presented for circular, folium, and spirograph trajectories, which are selected for their potential use as hurricane sampling trajectories. The theoretical results are illustrated using numerical simulations in an idealized hurricane model. Nomenclature N Number of particles in the system k Particle index k = 1,..., N rk Position of k th particle with respect to inertial frame r̃k Position of k th particle with respect to rotating fram
Cross-Country Transportation Efficacy and Clinical Outcomes of Preloaded Large-Diameter Ultra-Thin Descemet Stripping Automated Endothelial Keratoplasty Grafts
PURPOSE: To evaluate the clinical outcomes of preloaded large-diameter ultra-thin grafts for Descemet stripping automated endothelial keratoplasty (UT-DSAEK) after cross-country shipment. METHODS: A laboratory study in an eye bank and a clinical cohort study in an academic tertiary care center were performed. UT-DSAEK (9.5 mm diameter) grafts (n = 7) were prepared, loaded into a commercial device (iGlide; Eurobio, Les Ulis, France), preserved for 4 days at room temperature in transport medium, and analyzed. In a retrospective study, preloaded tissues (n = 39) for clinical use were prepared, transported from Italy to the United Kingdom, and surgically delivered into the eyes of patients undergoing UT-DSAEK. Central and peripheral endothelial cell density (ECD) and viability were measured before and after loading and storage of the grafts in the laboratory study. Clinically, best-corrected visual acuity, ECD before and at final follow-up, dislocation rate, primary graft failure, and surgical time were recorded. RESULTS: In the laboratory study, postcut central graft thickness was 93.3 ± 17.2 μm. ECD and cell mortality did not change significantly before and after preservation (P = 0.8). Cell loss after 4 days of preservation was 1.7% ± 1.6%. Clinically, 39 eyes of 39 patients at final follow-up showed a mean central graft thickness of 88 ± 22 μm and a best-corrected visual acuity of 0.34 ± 0.24 logMAR. Nine of 39 cases (23%) needed rebubbling, and 28% cell loss was observed at final follow-up. CONCLUSIONS: Large-diameter UT-DSAEK grafts can be prepared and preloaded in the eye bank using the iGlide and transported to the surgical center facilitating surgery for patients undergoing UT-DSAEK, potentially reducing tissue wastage, surgical time, and costs related to surgery
Intellectual property management and technological entrepreneurship
This paper investigates the distinctive technology protection strategies of entrepreneurial technology firms. In contrast with much popular opinion, it is reported that intellectual property features more prominently in the business of small entrepreneurial firms than it does in the business of large, established mature firms. The intellectual property portfolios of technology firms of all sizes and ages exhibit a rich array of instruments in addition to patents for protecting technology, including trade secrets, trademarks and copyright, together with licenses to externally sourced technology. The intellectual property profiles of technology firms appear to be influenced by their context, organizational profiles and corporate goals and by the character of their technology
Alcohol home delivery usage and its relationship to alcohol consumption in New South Wales during COVID-19
Background: Rapid growth in the use of alcohol home delivery services, combined with increases in home drinking during COVID-19, raised potential concerns around increased consumption. This paper aims to assess the relationship between alcohol home delivery use and consumption across levels of COVID-19 restrictions in New South Wales (NSW), Australia. Methods: A five-wave longitudinal survey of 586 NSW residents (Mage = 35; 65.3% female) conveniently sampled across 2020. Home delivery usage and the number of daily standard drinks consumed during a typical week were assessed with a survey. Logistic regression models were estimated within each wave to identify predictors of home delivery usage, and hierarchical logistic mixed effects models were estimated to predict purchase source (home delivery vs other) at the occasion level. Results: From baseline, alcohol home delivery use rose significantly during lockdown (20% to 34%), with respondents using home delivery during lockdown and the partial re-opening wave, consuming significantly more than those who were not. Use of home delivery was significantly higher during lockdown and the partial re-opening amongst people who drank more heavily, with respondents aged 36 or older more likely to use delivery services in all waves except lockdown. Conclusions: Alcohol home delivery usage increased during lockdown suggesting that restrictions impeding on-premise consumption coincided with an increase in home delivery. Associations between persons who drank more heavily and use of home delivery during lockdown and the partial re-opening point to a subset of the population that may be at increased risk of harmful consumption when accessing alcohol delivery services
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