The “Narratives” fMRI dataset for evaluating models of naturalistic language comprehension

The “Narratives” collection aggregates a variety of functional MRI datasets collected while human subjects listened to naturalistic spoken stories. The current release includes 345 subjects, 891 functional scans, and 27 diverse stories of varying duration totaling ~4.6 hours of unique stimuli (~43,000 words). This data collection is well-suited for naturalistic neuroimaging analysis, and is intended to serve as a benchmark for models of language and narrative comprehension. We provide standardized MRI data accompanied by rich metadata, preprocessed versions of the data ready for immediate use, and the spoken story stimuli with time-stamped phoneme- and word-level transcripts. All code and data are publicly available with full provenance in keeping with current best practices in transparent and reproducible neuroimaging

The Origin, Early Evolution and Predictability of Solar Eruptions

Coronal mass ejections (CMEs) were discovered in the early 1970s when space-borne coronagraphs revealed that eruptions of plasma are ejected from the Sun. Today, it is known that the Sun produces eruptive flares, filament eruptions, coronal mass ejections and failed eruptions; all thought to be due to a release of energy stored in the coronal magnetic field during its drastic reconfiguration. This review discusses the observations and physical mechanisms behind this eruptive activity, with a view to making an assessment of the current capability of forecasting these events for space weather risk and impact mitigation. Whilst a wealth of observations exist, and detailed models have been developed, there still exists a need to draw these approaches together. In particular more realistic models are encouraged in order to asses the full range of complexity of the solar atmosphere and the criteria for which an eruption is formed. From the observational side, a more detailed understanding of the role of photospheric flows and reconnection is needed in order to identify the evolutionary path that ultimately means a magnetic structure will erupt

Fracture Characteristics of Dental Ceramic Crown according to Zirconia Coping Design

AbstractFracture characteristics of the ceramic crown according to the zirconia coping design have been researched using various experimental methods. The 3D contour dimension of a mandibular first molar acrylic model tooth was scanned with Optical scanner (S600, Zirkonzahn, Italy), and then a classic crown preparation was created in CAD software (Zirkonzahn.Modellier, Zirkonzahn, Italy). The CAD file of the prepared tooth was imported into a milling machine, and acrylic resin (PMMA) dies were generated. Four different coping designs based on the thickness of zirconia marginal collar were used: 0.0mm zirconia collar (Group1), 0.5mm (Group2), 1.0mm (Group3), and 2.0mm (Group4). Copings were fabricated with CAD/CAM System (CAD CAM M5, Zirkonzahn, Italy) and veneering porcelain (IPS e.max Ceram) was build-up with layering technique. All the samples were cemented (RelyX Unicem, 3M/ESPE) onto corresponding dies. All specimens were tested in 4 groups (n=10 for each group) based on the thickness of zirconia collar. Fracture load test was performed on eight crowns from each group, and the remaining crowns (n=2) were subjected to fatigue test. Fracture strength was tested with a universal testing machine at a crosshead speed of 1.0mm/min to the vertical axis of the tooth 0.5mm lingually down the mesio-distal cusp. For the testing of fatigue failure, specimens were subjected to 50,000 cycles of cyclic loading 200N, at a rate of 15Hz and then loaded dynamically at a crosshead speed of 1.0mm/min, until failure. Fracture location and fracture surface of failed crowns were observed with a field emission scanning electron microscope (FE-SEM S-4800, Hitachi, Japan). Mean of fracture strength values of veneering porcelain were: 1411N for Group1, 1428N for Group2, 1596N for Group3 and 1621N for Group4. And according to increasing of thickness on zirconia collar, zirconia coping showed more fracture strength value with increasing of fracture strength of porcelain veneered it up. And examined using FE-SEM, two interesting features were shown from the fracture surface, sudden fracture and gradual fracture. And failure of specimens was mainly occurred by crack growth initiated from porosities within the veneering porcelain. In conclusion, according to the fracture test, the more thickness of zirconia collar, the higher fracture strength of veneering porcelain. Thus, zirconia coping design with 2.0mm marginal collar width is recommended for both functional longevity and esthetics of zirconia-ceramic restoration