Activity

  • Gustafsson posted an update 7 months, 1 week ago

    Exposure to poisonous plants is hazardous to health; thus, reliable species identification is required to decide the most appropriate treatment. Since ingested plants are too much degraded for visual observation, DNA barcoding can be used as a molecular tool for species identification. Considering the universal primers, PCR and sequencing success rate, and diversity of the poisonous plants, the rbcL DNA marker was selected for molecular identification. A reference DNA barcode library for 100 poisonous plant species was created using rbcL DNA barcodes. For the poisonous plants represented in the library, 100% and 89% species differentiation was observed at the genus and species level, respectively. All the undifferentiated species were congeneric species. Mapping the metabolites of the poisonous plants to the DNA based phylogenetic tree indicated that the phylogenetically related species also had related toxic compounds. Therefore, genus-level identification may be sufficient in the practical application of DNA barcoding in poisoning cases. We conclude that rbcL can be used as a primary marker, and if required, ITS2 or trnH-psbA may be used as a secondary marker to identify the poisonous plants. The present study provides the foundation to develop a reliable molecular method to identify the poisonous species from the vomit samples of poisoning cases.The ability to resist distracting stimuli whilst voluntarily focusing on a task is fundamental to our everyday cognitive functioning. Here, we investigated how this ability develops, and thereafter declines, across the lifespan using a single task/experiment. Young children (5-7 years), older children (10-11 years), young adults (20-27 years), and older adults (62-86 years) were presented with complex visual scenes. Endogenous (voluntary) attention was engaged by having the participants search for a visual target presented on either the left or right side of the display. The onset of the visual scenes was preceded – at stimulus onset asynchronies (SOAs) of 50, 200, or 500 ms – by a task-irrelevant sound (an exogenous crossmodal spatial distractor) delivered either on the same or opposite side as the visual target, or simultaneously on both sides (cued, uncued, or neutral trials, respectively). Age-related differences were revealed, especially in the extreme age-groups, which showed a greater impact of crossmodal spatial distractors. Young children were highly susceptible to exogenous spatial distraction at the shortest SOA (50 ms), whereas older adults were distracted at all SOAs, showing significant exogenous capture effects during the visual search task. By contrast, older children and young adults’ search performance was not significantly affected by crossmodal spatial distraction. Overall, these findings present a detailed picture of the developmental trajectory of endogenous resistance to crossmodal spatial distraction from childhood to old age and demonstrate a different efficiency in coping with distraction across the four age-groups studied.The purpose of this study was to quantify the magnitude and frequency content of surface-measured accelerations at each major human body segment from foot to head during impact landings. Twelve males performed two single leg drop landings from each of 0.15 m, 0.30 m, and 0.45 m. Triaxial accelerometers (2000 Hz) were positioned over the first metatarsophalangeal joint; distal anteromedial tibia; superior to the medial femoral condyle; L5 vertebra; and C6 vertebra. Analysis of acceleration signal power spectral densities revealed two distinct components, 2-14 Hz and 14-58 Hz, which were assumed to correspond to time domain signal joint rotations and elastic wave tissue deformation, respectively. selleck chemical Between each accelerometer position from the metatarsophalangeal joint to the L5 vertebra, signals exhibited decreased peak acceleration, increased time to peak acceleration, and decreased power spectral density integral of both the 2-14 Hz and 14-58 Hz components, with no further attenuation beyond the L5 vertebra. This resulted in peak accelerations close to vital organs of less than 10% of those at the foot. Following landings from greater heights, peak accelerations measured distally were greater, as was attenuation prior to the L5 position. Active and passive mechanisms within the lower limb therefore contribute to progressive attenuation of accelerations, preventing excessive accelerations from reaching the torso and head, even when distal accelerations are large.The Sneddon formula is conventionally used to calculate the elastic modulus of cell based on atomic force microscope (AFM) experiments. Owing to the disobedience of the formula assumptions, errors exist. Here, the ABAQUS for finite element modeling and analysis was used to simulate the process of compression of cell with a AFM conical probe. It was found that the relative error ranges from 0.094 to 1.455 folds, depending on half angle of the cone, curvature radius at the tip of the cone and the compression depth. By fitting the error data, we proposed a correction factor, which can be multiplied by the Sneddon formula to get a modified formula, providing the more accurate elastic modulus of cell. The experimentally measured elastic moduli of cell and hydrogel are in good agreement with the values obtained using the modified formula.This paper presents a computational and experimental analysis of a glaucoma flat drainage device (FDD). The FDD consists of a metallic microplate placed into the eye sclerocorneal limbus, which creates a virtual path between the anterior chamber and its exterior, allowing the intraocular pressure (IOP) to be kept in a normal range. It also uses the surrounding tissue as a flow regulator in order to provide close values of IOP for a wide range of aqueous humor (AH) flow rates. The Neo Hookean hyperelastic model is used for the solid part, while the Reynolds thin film fluid model is used for the fluid part. On the other hand, a gravitational-driven flow test is implemented in order to validate the simulation process. An in vitro experiment evaluated the flow characteristics of the device implanted in fourteen extirpated pig eyes, giving as a result the best-fit for the Young modulus of the tissue surrounding the device. Finally, according to the resulting computational model, for a range of 1.4-3.1 μL/min, the device presents a pressure variation range of 6-7.

Skip to toolbar