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One way to improve the value of citizen science data for a specific aim is through promoting adaptive sampling, where the marginal value of a citizen science observation is dependent on existing data collected to address a specific question. Adaptive sampling could increase sampling at places or times—using a dynamic and updateable framework—where data are expected to be most informative for a given ecological question or conservation goal. We used an experimental approach to test whether the participants in a popular Australian citizen science project—FrogID—would follow an adaptive sampling protocol aiming to maximize understanding of frog diversity. After a year, our results demonstrated that these citizen science participants were willing to adopt an adaptive sampling protocol, improving the sampling of biodiversity consistent with a specific aim. Such adaptive sampling can increase the value of citizen science data for biodiversity research and open up new avenues for citizen science project design.

Neural activation on fMRI during semantic processing was examined in 38 older adults, 55–85 years of age, experiencing successfully cognitive aging, without mild cognitive impairment (MCI) or evidence of neurodegenerative disease. A mixed event-related block paradigm on which judgements were made as to whether semantic (abstract and concrete) and phonemic (rhyme) word-pairs were associated or unassociated during task-dependent fMRI. As hypothesized, greater activation intensity occurred during the processing of associated vs. unassociated, and to semantic vs. phonemic word-pairs in putative semantic hubs-control areas (angular gyrus, anterior middle temporal gyrus, and inferior frontal gyrus), and in secondary association areas. Several areas activated more to unassociated word-pairs, notably the hippocampus and thalamus. Cortical area exhibited similar activation intensity between semantic conditions, though several areas activated more during either abstract or concrete processing. Activation intensity of the left inferior frontal gyrus was greater during abstract processing, but not in the left angular or anterior temporal gyri. Greater age was associated with relatively few differences in cortical activation, though greater right homologous activation occurred in the angular gyrus, supramarginal gyrus, and the precuneus during the processing of strongly vs. weakly associated concrete word-pairs. Activation intensity did not differ across semantic conditions with greater age otherwise, suggesting that neural response of the semantic hubs, control and secondary cortical association areas is relatively preserved in older adults without MCI or neurodegenerative disease. Age-associated differences in neural activation are likely task-dependent, evident when there is greater demand for semantic control and generation among older adults.

Magnetic wellbore positioning depends on an accurate representation of the Earth's magnetic field,where the borehole azimuth is inferred by comparing the magnetic field measured-whiledrilling (MWD) with a geomagnetic reference model. Therefore, model accuracy improvements reduce the position uncertainties. An improved high-resolution model describing the core, crustal and external components of the magnetic field is presented, and it is validated with anindependent set of measurements. Additionally, we benchmark it against other high-resolution geomagnetic models. The crustal part of the improved high-definition model is based on NOAA/NCEI's latest magnetic survey compilation "EMAG2v3" which includes over 50 millionnew observations in several parts of the world, including the Gulf of Mexico and Antarctica, and does not rely on any prior information from sea-floor geology, unlike earlier versions. The core field part of the model covers years 1900 through 2020 andis inferred from polar-orbiting satellite data as well as ground magnetic observatory data. The external field part is modelled to degree and order 1 for years 2000 through 2020. The new model has internal coefficients to spherical harmonic degree and order 790, resolving magnetic anomalies to approximately 51 km wavelength at the equator. In order to quantitatively assess its accuracy, the model was compared with independent shipborne, airborne and ground magnetic measurements. We find that the newmodel has comparable or smaller errors than the other models benchmarkedagainst it over the regions of comparisons. Additionally, we compare theimproved model against magnetic datacollected from MWD; the residual error lies well within the accepted industry error model, which may lead tofuture error model improvements.

Polyolefins dominate the market for commodity plastics due to their low cost and suitable properties, but polyolefins are rarely used in 3D printing due to issues with deformation of the printed st...

Fans and hemispheres comprised of crystals of calcium carbonate that directly grew on the seafloor are an intriguing feature of ancient carbonate environments. Calcium carbonate fans from across Earth history are typically made up of crystals of neomorphosed calcium carbonate that maintain an acicular morphology that is pseudohexagonal in cross – section with blunt terminations, pointing to an aragonite precursor. Crystal fans may occur as isolated bodies, or may form larger aggregates that are sometimes associated with microbialites, and form larger, reef – like structures. Some of the first occurrences of these features are within Neoarchean carbonates, when the crystals fans grew to impressive sizes, with lengths of over 1 m, formed layers of marine cement that reached thicknesses of up to several meters, are laterally continuous over 10s of km or more, and formed across carbonate platform settings from high energy subtidal settings to lower intertidal environments. Crystalline carbonate fans become less common and smaller (cm – scale) in the Paleoproterozoic, and nearly disappear prior to the Neoproterozoic, when they are associated with cap carbonates, and are primarily found in deeper water or outer shelf settings with low sedimentation rates. Seafloor cements are rare during the Phanerozoic, and are typically limited to small geographic areas with unusual sedimentary conditions, or are found in void spaces, where seawater chemistry was able to undergo modifications that would allow precipitation of cement fans. The exception is during the interval of time that followed the Permian – Triassic mass extinction, when small, cm – scale fans and hemispheres are found in Lower Triassic and lowermost Middle Triassic rocks. These cement fans occur in a variety of settings, although they are typically found in deeper water environments. Calcium carbonate fans that formed following the Permian – Triassic extinction may have microbial remains preserved within the cements, and are frequently found in close lateral or stratigraphic association with microbialites. However, some examples of post – extinction carbonate fans appear to have formed abiotically, without any microbial influence. Overall, crystalline calcium carbonate fans signal high levels of calcium carbonate supersaturation in ancient oceans. The initial decline in seafloor cement growth from the Neoarchean into the Proterozoic may have been the result of accelerated micrite production, while Neoproterozoic calcium carbonate fan growth is associated with glacial decay and retreat. Lower Triassic seafloor cements are likely the result of stratification and stagnation of the deep oceans that led to enhanced alkalinity. Calcium carbonate crystal fans are an intriguing feature of ancient carbonates that signal depositional systems and ocean chemistry that is much different from modern ocean, and provide a fascinating glimpse into non – uniformitarian sedimentary environments.

Purpose. There is a lack of identifying suitable regions in the head that can be used for three-dimensional superimposition techniques. For this reason, with the use of cone-beam computed tomography (CBCT), the ear canals were analyzed to verify changes during a period of three years in the adolescent years.Methods. CBCTs from fifty-six patients (ages: 10 to 20) were used to landmark the anatomy of the ear canals. Each patient was analyzed using two CBCT reconstructions that were taken approximately three years apart. AVIZO® software was used to locate 28 landmarks distributed following the ear canal path and foramina (ovale, spinosum, rotundum, etc.) in the cranial base to obtain spatial relationships. Three-dimensional coordinates were obtained from the landmarks, and the average distance between various landmark pairings was calculated. The repeated measure ANCOVA was used to determine statistical significance.Results. In the main data set, the largest mean distance change was found to be 4.37 mm ± 18.29 mm between the left foramen ovale and the left superior medial ear canal opening. The smallest mean distance change was 0.18 mm ± 3.25 mm between the right inferior lateral ear canal opening and the right inferior medial ear canal opening.Conclusions. During the adolescent years, the ear canal presents dimensional changes. Even though in different areas throughout the canal, the average distances were minor, still, large standard deviations were present; thus, caution should be taken when trying to use this structure for superimposition of CBCTs.

Cold in-place recycling (CIR) is one of the most popular rehabilitation techniques in Iowa. The Iowa Department of Transportation has increased the minimum moisture criterion from 1.5% to 2.0% because many overlays have been successfully applied on the CIR layer with moisture contents above 2.0%. However, a contractor must make daily measurements of the moisture content with a nuclear gauge. It is difficult to achieve 2.0% moisture content during a rainy summer in Iowa. For the curing issue to be addressed systematically, the moisture contents and temperatures of one project of CIR with emulsified asphalt and four projects of CIR with foamed asphalt were monitored. Capacitance moisture and temperature sensors were embedded at the midpoint of the CIR layer to measure moisture contents and pavement temperature. A GeoGauge was used to measure the stiffness. The field data obtained from the embedded moisture sensors and from a weather station were used to develop a moisture prediction model as a function of the initial moisture content, CIR layer temperature, wind speed, and humidity. With the developed moisture prediction model, a contractor can predict optimal timing for placement of the wearing surface without continually measuring moisture contents of the CIR layer with a nuclear gauge. The stiffness of the CIR layer measured with the GeoGauge was found to continue to increase as the curing period increased, despite an increase in moisture content caused by rainfall. The stiffness measured by the GeoGauge steadily increased during the curing period until it reached a value of 30 MN/m. For the optimal timing of an overlay to be determined, the stiffness, rather than the moisture, of the CIR layer should be measured.

Study Design. Retrospective case series.Objective. To document the clinical utility of intraoperative neuromonitoring during minimally invasive surgical sacroiliac joint fusion for patients diagnosed with sacroiliac joint dysfunction (as a direct result of sacroiliac joint disruptions or degenerative sacroiliitis) and determine stimulated electromyography thresholds reflective of favorable implant position.Summary of Background Data. Intraoperative neuromonitoring is a well-accepted adjunct to minimally invasive pedicle screw placement. The utility of intraoperative neuromonitoring during minimally invasive surgical sacroiliac joint fusion using a series of triangular, titanium porous plasma coated implants has not been evaluated.Methods. A medical chart review of consecutive patients treated with minimally invasive surgical sacroiliac joint fusion was undertaken at a single center. Baseline patient demographics and medical history, intraoperative electromyography thresholds, and perioperative adverse events were collected after obtaining IRB approval.Results. 111 implants were placed in 37 patients. Sensitivity of EMG was 80% and specificity was 97%. Intraoperative neuromonitoring potentially avoided neurologic sequelae as a result of improper positioning in 7% of implants.Conclusions. The results of this study suggest that intraoperative neuromonitoring may be a useful adjunct to minimally invasive surgical sacroiliac joint fusion in avoiding nerve injury during implant placement.