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  • Transcranial alternating current stimulation (tACS) can affect perception, learning and cognition, but the underlying mechanisms are not well understood. A promising strategy to elucidate these mechanisms aims at applying tACS while electric or magnetic brain oscillations targeted by stimulation are recorded. However, reconstructing brain oscillations targeted by tACS remains a challenging problem due to stimulation artifacts. Besides lack of an established strategy to effectively supress such stimulation artifacts, there are also no resources available that allow for the development and testing of new and effective tACS artefact suppression algorithms, such as adaptive spatial filtering using beamforming or signal-space projection. Here, we provide a full dataset comprising encephalographic (EEG) recordings across six healthy human volunteers who underwent 10-Hz amplitude-modulated tACS (AM-tACS) during a 10-Hz steady-state visually evoked potential (SSVEP) paradigm. Moreover, data and scripts are provided related to the validation of a novel stimulation artefact suppression strategy, Stimulation Artifact Source Separation (SASS), removing EEG signal components that are maximally different in the presence versus absence of stimulation. Besides including EEG single-trial data and comparisons of 10-Hz brain oscillatory phase and amplitude recorded across three conditions (condition 1: no stimulation, condition 2: stimulation with SASS, condition 3: stimulation without SASS), also power spectra and topographies of SSVEP amplitudes across all three conditions are presented. Moreover, data is provided for assessing nonlinear modulations of the stimulation artifact in both time and frequency domains due to heartbeats. Finally, the dataset includes eigenvalue spectra and spatial patterns of signal components that were identified and removed by SASS for stimulation artefact suppression at the target frequency. Besides providing an valuable resource to assess properties of AM-tACS artifacts in the EEG, this dataset allows for testing different artifact rejection methods and offers in-depth insights into the workings of SASS.
    Data Types:
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  • The proposed dataset aims to benchmark the performance of SfM software under varying conditions - different environments, different lighting, image positions, camera setups, etc. Images of six objects are provided with varying shapes, sizes, surface textures and materials. The dataset is divided in two main parts, together with ReadMe files: - Objects and environments data - images from each of the objects both from indoor and outdoor environments are provided. - Capturing setups data - images from one of the objects are provided captured with different setups. Both with and without using a turntable, using one and multiple light sources and different amount of images All images are captured using Canon 6D DSLR camera. All images contain EXIF data with used camera parameters. A ground truth high resolution scanned of each of the objects is provided for verifying the accuracy of the SfM reconstructions.
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  • Dataset from the study "THE POSTERIOR INSULAR CORTEX IS NECESSARY FOR THE CONSOLIDATION OF TONE FEAR CONDITIONING"
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  • WAXD and SAXS patterns of poly(ɛ-caprolactone) (PCL) monofilaments were recorded on a Bruker Nanostar U diffractometer (Bruker AXS, Karlsruhe, Germany) with a Cu-Kα radiation λ = 1.5419 Å and a VÅNTEC-2000 MikroGap area detector. Mechanical properties were measured with the tensile testing machine Statimat ME+ (Textechno, Germany). Thermal properties were characterized using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Rheological properties of the PCL polymer were characterized with the Rheometer Physica MCR 301 (Anton Paar), using a plate-plate geometry. The surface topography of fibers was analyzed using the scanning electron microscope (SEM) FE-SEM S-4800 (Hitachi High-Technologies Europe, Krefeld, Germany) with an acceleration voltage of 5.0 kV.
    Data Types:
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  • The present dataset is a collection of information about the biomechanical behavior and histological characterization of abdominal aortic aneurysms (AAA) harvested during the autopsy procedure. The primary hypothesis of the present research is: Do cadaveric AAA walls, when previously stressed by inflation, conserve significant resistance against tearing comparable to no previously stressed aortas described in the literature? Eight AAAs (6 fusiform and two saccular) were carefully dissected and had their branches ligated with cotton or prolene sutures. Each specimen was submitted to intraluminal pressurization, up to the rupture of their wall. This pressurization was made through the inflation of an air balloon inside the specimens up to their rupture. From the border of the rupture sites, and from the proximal (control sample 1) and distal (control sample 2) no dilated portions of each vessel, samples were harvested for uniaxial tensile tests, and histological analysis. The uniaxial tensile test utilized the INSTRON SPEC 2200 device and was coordinated by INSPEC software and SERIES IX software. The essential variables collected through this test are failure stress, failure tension, and failure strain. Each sample test generated a chart representing the relationship between stress and strain. The histological analysis included hematoxylin-eosin, Picrocirius, and Voerhoeff stains. Unfortunately, some samples were lost, especially during histological processing. A quantitative analysis (collagen and elastic fibers) was made using the software Pannoramic Viewer and Case Viewer.1 Notable findings: Even after being stretched/stressed up to their rupture, the specimens conserved uniaxial biomechanical properties comparable to AAA and normal aorta samples previously described in the literature by Monteiro e Nynomiya respectively.2,3 DATA DESCRIPTION: a) Biomechanical Data: As explained above, four samples were collected for each specimen, two from each side of the rupture border and two control samples, one from a proximal and a second from a distal region of the vessel. It is important to highlight here that some samples did not produce valid biomechanical tests, so they do not have their results included here. For each valid sample test, three documents are generated: 1. Stress X strain chart 2. Table (excel file containing all the values related to the stress X strain chart 3. A report from the Biomechanical test software containing details of the test All charts contain a notification in their left upper corner about the failure stress, strain and tension of each sample. b) Histological Data: The percentage of coverage of collagen fibers and elastin fibers is expressed in table I in decimal numbers (for example, 0.36 = 36%). Similarly to the sampling for biomechanical tests, four samples were harvested from each aorta, when it was feasible. Ps.: All Case C samples were lost during processing
    Data Types:
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  • The proposed dataset aims to provide a number of wind turbine blade images for testing and training purposes. The featured datasets can be used for testing and evaluation of Structure from Motion algorithms for 3D reconstruction, as data for machine learning algorithms for detecting damaged areas on blades or for quantifying blade surface roughness. Images are taken using Canon 5Ds DSLR camera with resolution of 8688 x 5792. The images come with EXIF data, containing additional information about the used capturing settings. The dataset is separated into two parts: - A dataset containing 5 wind turbine blade patches of areas of different surface structure. Two of the patches are of damaged areas, two of the patches are of rough areas, without pronounced surface deformations and one of the patches is a reference area, that does not contain any roughness or damages. The final patch contains the whole of the blade's edge area and is comprised of a mix of severely damaged areas, areas of small roughness and clear areas. The dataset also contains ground truth microscopy data for two of the damaged patches. The ground truth is scaled to absolute scale. - A dataset containing images of a small blade segment. The blade has been sand blasted, to imitate prolonged real world use. The images are taken both outdoor and indoor. The indoor images contain patches specifying areas of interest - one containing a rough patch and one containing damages. The outdoor images are focused on the whole blade and do not contain patches. The dataset also contains ground truth microscopy data for the two patches, which is scaled to absolute scale.
    Data Types:
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  • The present dataset is a collection of information about the biomechanical behavior and histological characterization of normal diameter abdominal aortas harvested during the autopsy procedure. The primary hypothesis of the present research is: Do cadaveric abdominal aortic walls, when previously stressed by inflation, conserve significant resistance against tearing comparable to no previously stressed aortas described in the literature? Thirty normal diameter abdominal aortas were carefully dissected and had their branches ligated with cotton or prolene sutures. Each specimen was submitted to intraluminal pressurization, up to the rupture of their wall. This pressurization was made through the inflation of an air balloon inside the specimens up to their rupture. From the border of the rupture sites, and from the proximal (control sample 1) and distal (control sample 2) portions of each vessel, samples were harvested for uniaxial tensile tests, and histological analysis. The uniaxial tensile test utilized the INSTRON SPEC 2200 device and was coordinated by INSPEC software and SERIES IX software. The essential variables collected through this test are failure stress, failure tension, and failure strain. Each sample test generated a graph representing the relationship between stress and strain. The histological analysis included hematoxylin-eosin, Picrosirius, and Voerhoeff stains1. Unfortunately, some samples were lost, especially during histological processing. A quantitative analysis (collagen fibers and elastic fibers percentage of coverage) was made using the software Pannoramic Viewer and Case Viewer. Notable findings: Even after being stretched/stressed up to their rupture, the specimens conserved some uniaxial biomechanical properties comparable to normal diameter aorta samples previously described in the literature by Monteiro e Nynomiya respectively.2,3 DATA DESCRIPTION: a) Biomechanical Data: As explained above, whenever possible, four samples were collected from each specimen destinated to the biomechanical test. It is important to highlight that some samples did not produce valid biomechanical tests, so they do not have their results included here. For each valid sample test, three documents were generated: 1. Stress X strain graph (all graphs contain a notification in their left upper corner about the failure stress, strain and tension of each sample). 2. Table (excel file containing all the values related to the stress X strain graph 3. A report from the Biomechanical test software containing details of the test All available files related to the biomechanical tests of these 30 normal aortas were included in the present dataset. b) Histological Data: The percentage of coverage of collagen fibers and elastin fibers is expressed in the table "HISTOLOGY - NORMAL AORTAS.xls in decimal numbers (for example, 0.36 = 36%). Four samples were harvested from each aorta, when it was feasible.
    Data Types:
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  • The proposed dataset can be used to test the precision of scaling SfM reconstructed objects using camera positioning data. In addition position uncertainty data from a DJI GPS RTK in X,Y and Z is added, so the propagation of uncertainty from the positioning sensor to the calculated scale can be calculated. The camera positions are also given with any uncertainty, so other types of position uncertainty can be used to test how the system will react with different uncertainty inputs. Images from two objects are given - an angel statue and a wind turbine blade. Images are taken in a semi-circle pattern around the object and a total of 19 images are taken from each object. The positions of the images are given in a separate file, while all the images contain EXIF data with the used camera parameters. All images are captured using Canon 5Ds DSLR camera. More information on how the scale and scale uncertainty can be calculated are present in the referenced paper.
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  • Case 1: A 67-year-old Caucasian male was hospitalized for COVID-19 (nasopharyngeal swab PCR-confirmed) management. His symptoms began 10 days prior with low-grade fever, nasal congestion, post-nasal drip, and cough without shortness of breath. Seven days into his symptoms, he noted a transient non-pruritic blanching unilateral livedoid patch on the right anterior thigh resembling LR (Figure 1). The eruption lasted for 19 hours and resolved by the time dermatology evaluated the patient; thus no biopsy was taken. Concurrent with the lacy patches on the leg, the patient also noted gross hematuria and generalized weakness. In concert with the netlike exanthem, the hematuria resolved within 24 hours. He was eventually discharged home stable on supplemental oxygen. Case 2: A 47-year-old Caucasian female with history of Celiac disease, Hashimoto’s thyroiditis, and portal vein thrombosis in 2017 with negative work-up for a hypercoagulable state (attributed to a long plane flight combined with prior oral contraceptive) tested COVID-19-positive. Symptoms began with a mild headache, sinus pressure, anosmia, and fever, with highest recorded temperature of 37.9°C. Ten days after testing positive, and with complete clinical convalescence of COVID-19 symptoms, she was sitting outside in long pants under direct sunlight for approximately 20-30 minutes. A unilateral asymptomatic rash on her right leg resembling LR was noticed incidentally immediately upon moving indoors (Figure 2) despite an equal amount of sun exposure on both legs. The rash lasted approximately 20 minutes and did not recur upon re-challenge with sun exposure the following day. Discussion Livedo reticularis is caused by conditions, including disseminated intravascular coagulation (DIC), that reduce blood flow through the cutaneous microvasculature system leading to deoxygenated blood accumulation in the venous plexus.3 We hypothesize that the microthromboses that manifest in other organs (e.g. cardiopulmonary)4 and as DIC2,5 in critically ill COVID-19 patients are the most plausible etiology to our patients' LR presentations. We postulate that manifestations can vary from transient LR in mild-moderate cases to acrocyanosis in critically ill patients. Because our patients were not critically ill, perhaps they had transient low-grade DIC, and the concurrent hematuria in Patient 1 could be explained by a possible micro-embolic event causing glomerulonephritis or cystitis. However, due to the evanescent nature of their LR-like eruptions, they were not biopsied. Interestingly, exanthems have not been described for other coronaviruses such as SARS-CoV and MERS-CoV. In the future, histopathology of active exanthema may be helpful in elucidating the underlying pathology of the cutaneous and perhaps systemic manifestations of COVID-19 infection. Additionally, platelet count, coagulation studies, and fibrin degradation products assessments in these patients would be enlightening.
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  • Synthetic COVID-19 dataset, including 1186 chest CT images These data come from ‘Deep Learning for COVID-19 chest CT (computed tomography) image analysis’ The deep learning model used in the paper is CycleGAN, and the classification experiment is used to test the usability of the Synthetic COVID-19 dataset
    Data Types:
    • Image
    • Dataset