31 research outputs found
Assessment of contrast enhanced mammography:towards a full-fledged clinical tool for breast cancer diagnosis and screening
Using Galvanic Vestibular Stimulation to Induce Post-Roll Illusion in a Fixed-Base Flight Simulator
INTRODUCTION: The illusions of head motion induced by galvanic vestibular stimulation (GVS) can be used to compromise flight performance of pilots in fixed-base simulators. However, the stimuli used in the majority of studies fail to mimic disorientation in realistic flight because they are independent from the simulated aircraft motion. This study investigated the potential of bilateral-bipolar GVS coupled to aircraft roll in a fixed-base simulator to mimic vestibular spatial disorientation illusions, specifically the “post-roll illusion” observed during flight.METHODS: There were 14 nonpilot subjects exposed to roll stimuli in a flight simulator operating in a fixed-base mode. GVS was delivered via carbon rubber electrodes on the mastoid processes. The electrical stimulus was driven by the high-pass filtered aircraft roll rate to mimic the semicircular canals’ physiological response. The post-roll test scenarios excluded outside visual cues or instruments and required subjects to actively maintain a constant bank angle after an abrupt stop following a passive prolonged roll maneuver. The anticipated outcome was an overshot in roll elicited by the GVS signal. RESULTS: The responses across subjects showed large variability, with less than a third aligning with the post-roll illusion. Subjective ratings suggest that the high-pass filtered GVS stimuli were mild and did not induce a clear sense of roll direction. However, uncontrolled head movements during stimulation might have obscured the intended effects of GVS-evoked illusory head movements. CONCLUSION: The mild and transient GVS stimuli used in this study, together with the uncontrolled head movements, did not convincingly mimic the post-roll illusion.</p
Reversal of the hanging protocol of Contrast Enhanced Mammography leads to similar diagnostic performance yet decreased reading times
Objectives: Contrast-enhanced mammography (CEM) was found superior to Full-Field Digital Mammography (FFDM) for breast cancer detection. Current hanging protocols show low-energy (LE, similar to FFDM) images first, followed by recombined (RC) images. However, evidence regarding which hanging protocol leads to the most efficient reading process and highest diagnostic performance is lacking. This study investigates the effects of hanging-protocol ordering on the reading process and diagnostic performance of breast radiologists using eye-tracking methodology. Furthermore, it investigates differences in reading processes and diagnostic performance between LE, RC and FFDM images. Materials and methods: Twenty-seven breast radiologists were randomized into three reading groups: LE–RC (commonly used hangings), RC-LE (reversed hangings) and FFDM. Thirty cases (nine malignant) were used. Fixation count, net dwell time and time-to-first fixation on malignancies as visual search measures were registered by the eye-tracker. Reading time per image was measured. Participants clicked on suspicious lesions to determine sensitivity and specificity. Area-under-the-ROC-curve (AUC) values were calculated. Results: RC-LE scored identical on visual search measures, t(16)= -1.45, p =.17 or higher-p values, decreased reading time with 31%, t(16)= -2.20, p =.04, while scoring similar diagnostic performance compared to LE-RC, t(13.2)= -1.39, p -.20 or higher p-values. The reading process was more efficient on RC compared to LE. Diagnostic performance of CEM was superior to FFDM; F (2,26)= 16.1, p <.001. Average reading time did not differ between the three groups, F (2,25)= 3.15, p =.06. Conclusion: The reversed CEM hanging protocol (RC-LE) scored similar on diagnostic performance compared to LE-RC, while reading time was a third faster. Abnormalities were interpreted quicker on RC images. A RC-LE hanging protocol is therefore recommended for clinical practice and training. Diagnostic performance of CEM was (again) superior to FFDM
The impact of late treatment-toxicity on generic health-related quality of life in head and neck cancer patients after radiotherapy
SummaryTo examine the impact of late treatment-related xerostomia and dysphagia on health-related quality of life (HRQOL) in head and neck cancer (HNC) patients after radiotherapy. A multi-center cross-sectional survey was performed. Patients with a follow-up of at least 6months after curative radiotherapy, without evidence of recurrent disease were eligible for inclusion. The Euroqol-5D questionnaire (EQ-5D) was filled out and toxicity was scored and converted to the RTOG scale. The EQ-5D measures generic HRQOL in terms of utility and visual analogue scale (VAS) scores. Missing data on the EQ-5D were imputed using multiple imputation. HRQOL was compared between subgroups of patients with and without toxicity. Subsequently, the impact of xerostomia and dysphagia on HRQOL was analyzed using multivariate regression analyses. Both analyses were performed separately for utility scores and VAS scores. The study population was composed of 396 HNC patients. The average utility and VAS scores were 0.85 (scale 0–1) and 75 (scale 0–100). Subgroups of patients with xerostomia and/or dysphagia showed statistically significantly lower utility and VAS scores (P=0.000–0.022). The multivariate regression model showed that xerostomia and dysphagia were negative predictors of both utility and VAS scores. Other factors which influenced HRQOL in at least one of the two regression models were: sex, tumor location and the addition of surgery to radiotherapy. Xerostomia and dysphagia diminish generic HRQOL. Moreover dysphagia affects patients’ HRQOL stronger than xerostomia
Whole genome sequencing of turbot (Scophthalmus maximus; Pleuronectiformes):a fish adapted to demersal life
12 páginas, 5 figuras.-- Antonio Figueras ... et al.-- This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly citedThe turbot is a flatfish (Pleuronectiformes) with increasing commercial value, which has prompted active genomic research aimed at more efficient selection. Here we present the sequence and annotation of the turbot genome, which represents a milestone for both boosting breeding programmes and ascertaining the origin and diversification of flatfish. We compare the turbot genome with model fish genomes to investigate teleost chromosome evolution. We observe a conserved macrosyntenic pattern within Percomorpha and identify large syntenic blocks within the turbot genome related to the teleost genome duplication. We identify gene family expansions and positive selection of genes associated with vision and metabolism of membrane lipids, which suggests adaptation to demersal lifestyle and to cold temperatures, respectively. Our data indicate a quick evolution and diversification of flatfish to adapt to benthic life and provide clues for understanding their controversial origin. Moreover, we investigate the genomic architecture of growth, sex determination and disease resistance, key traits for understanding local adaptation and boosting turbot production, by mapping candidate genes and previously reported quantitative trait loci. The genomic architecture of these productive traits has allowed the identification of candidate genes and enriched pathways that may represent useful information for future marker-assisted selection in turbotThis work was funded by the Spanish Government: projects Consolider
Ingenio: Aquagenomics (CSD2007-00002) and Metagenoma
de la Península Ibérica (CSD2007-00005), Ministerio de Economía
y Competitividad and European Regional Development Funds
(AGL2012-35904), and Ministerio de Economía y Competitividad
(AGL2014-51773 and AGL2014-57065-R); and Local Government
Xunta de Galicia (GRC2014/010). P.P. and D.R. gratefully acknowledge
the Spanish Ministerio de Educación for their FPU fellowships
(AP2010-2408, AP2012-0254). Funding to pay the Open Access publication
charges for this article was provided by the Ministerio de
Economía y Competitividad (AGL2014-51773) and Xunta de Galicia
(GRC2014/010)Peer reviewe
Using Galvanic Vestibular Stimulation to Induce Post-Roll Illusion in a Fixed-Base Flight Simulator
INTRODUCTION: The illusions of head motion induced by galvanic vestibular stimulation (GVS) can be used to compromise flight performance of pilots in fixed-base simulators. However, the stimuli used in the majority of studies fail to mimic disorientation in realistic flight because they are independent from the simulated aircraft motion. This study investigated the potential of bilateral-bipolar GVS coupled to aircraft roll in a fixed-base simulator to mimic vestibular spatial disorientation illusions, specifically the “post-roll illusion” observed during flight.METHODS: There were 14 nonpilot subjects exposed to roll stimuli in a flight simulator operating in a fixed-base mode. GVS was delivered via carbon rubber electrodes on the mastoid processes. The electrical stimulus was driven by the high-pass filtered aircraft roll rate to mimic the semicircular canals’ physiological response. The post-roll test scenarios excluded outside visual cues or instruments and required subjects to actively maintain a constant bank angle after an abrupt stop following a passive prolonged roll maneuver. The anticipated outcome was an overshot in roll elicited by the GVS signal. RESULTS: The responses across subjects showed large variability, with less than a third aligning with the post-roll illusion. Subjective ratings suggest that the high-pass filtered GVS stimuli were mild and did not induce a clear sense of roll direction. However, uncontrolled head movements during stimulation might have obscured the intended effects of GVS-evoked illusory head movements. CONCLUSION: The mild and transient GVS stimuli used in this study, together with the uncontrolled head movements, did not convincingly mimic the post-roll illusion.</p
Een complex probleem
In order to improve the connection between punishment and care, the Ministry of Justice has recently been provided with its own budget for procuring care for addicts who are subject to measures. Procurement is in first instance aimed at the complex group of persons subject to judicial measures with triple problems: problematic drug use, psychiatric problems and mild learning disabilities. Little is known about this group. This study is intended to provide insight into this group
Tortuous mixed matrix membranes: A subtle balance between microporosity and compatibility
In this work, the effectiveness of metal-organic frameworks (MOFs) with sheet-like morphologies was assessed as function of the MOF microporosity and MOF-matrix compatibility. Zeolitic imidazolate frameworks (ZIFs, a MOF subclass) with sheet-like/platelet morphologies were incorporated in Matrimid/PBI matrices resulting in mixed matrix membranes (MMMs). The ZIFs were either permeable (ZIF-301) or impermeable (ZIF-95X) for gases with a kinetic diameter bigger than or equal to the kinetic diameter of CO2. Additionally, MMMs containing impermeable graphene nanosheets were fabricated as reference to confirm the ZIF-95X impermeability. The MMMs containing the ZIF-301 nanoplatelets showed enhanced CO2 permeabilities. Analysis of the N2 and CO2 solubility and diffusivity showed that this permeable additive enhances the solubility of both gases, but only increases the N2 diffusivity through the ZIF-301 MMM. This signified that for MMMs with sheet-like MOFs the MOF micropore volume should only be accessible for one gas such that the sheet-like morphology effectively increases the tortuosity for the other species. Contrarily, the MMMs containing impermeable ZIF-95X and graphene showed declined MMM separation performances. Analysis of the N2 and CO2 diffusivities showed the presence of defective interfaces in these MMMs and proved that an increased tortuosity is only effective if the additive-matrix interface is defect free
Tailoring the separation performance of ZIF-based mixed matrix membranes by MOF-matrix interfacial compatibilization
Controlling the metal-organic framework (MOF)-matrix interface is a useful strategy to improve the gas separation performance of mixed matrix membranes (MMMs). Although polymer blending has been investigated to enhance MMM performances, its true strength, i.e., aligning polymer and additive chemistries to improve interfacial compatibility and ultimately the separation performance, is only poorly investigated. In this work we demonstrate how controlling interfacial chemistries by polymer blending is an effective tool to tune the membrane performance. Three isoreticular zeolitic imidazolate frameworks (ZIFs) and two matrix polymers (Matrimid and polybenzimidazole oPBI (PBI)) were used to prepare the MMMs. The ZIF linker functionality strongly determined the extent of the effect of PBI addition in the MMMs. For both the hydrophobic ZIF-7 and ZIF-8-based MMMs, PBI compatibilized the MOF-matrix interface and increased the CO2/N2 separation factor while slightly decreasing the permeability. Contrarily, the separation performance of the hydrophilic ZIF-90 MMM was not affected by PBI incorporation. Additionally, the MMM permeability followed the trend of the ZIF pore geometries and linker flexibilities. These results proved that MOF-matrix interfacial compatibility can effectively be controlled by polymer blending and that the extent of control is determined by a subtle balance between the MOF linker functionality and matrix chemistry