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A new finding over the past decade is the stability – and even potential synthesis – of hydrocarbons at depth in Earth. Of course, this has been a highly controversial area of research for decades, but recent evidence has been obtained from natural orogenic geological settings, thermodynamic simulations, and observations of seafloor samples. This chapter reviews this new evidence while highlighting the importance of the physical state of C-O-H fluids contained in rocks on the transport of alkanes like methane, propane, and octane, the impact of pore space and fracture confinement on fluid reactivity, and how reactivity under confinement varies from bulk fluid properties.
The philosophy of Gilles Deleuze has become popular in recent moves to embed approaches such as the new materialist and the posthuman in environmental education. Certainly, a newfound respect for the material universe, including the comprehension of the human place in it, and the tendency to a posthuman theoretical position, are both important given the contemporary environmental crisis, named as the Anthropocene. However, this article will argue that both these philosophies do not go far enough. This is because they must retain a political, social and critical edge if they are to be effective, and this edge can be too easily disregarded in the pursuit of increased engagement with the material and everything not human. In contrast, this article will put forward a Deleuzian approach to environmental education, based on the intellectual quadrant of Spinoza-Marx-Nietzsche-Bergson (Figure 1). It will be argued that only by fully connecting these often conflicting and disparate philosophies that a workable new synthesis for environmental education and a cartography for learning can be achieved. The Deleuzian approach to environmental education will be exemplified through an analysis of current environmental practises in schools as assemblage.
BMI z (BMIz) score based on the Centers for Disease Control and Prevention growth charts is widely used, but it is inaccurate above the 97th percentile. We explored the performance of alternative metrics based on the absolute distance or % distance of a child’s BMI from the median BMI for sex and age. We used longitudinal data from 5628 children who were first examined <12 years to compare the tracking of three BMI metrics: distance from median, % distance from median and % distance from median on a log scale. We also explored the effects of adjusting these metrics for age differences in the distribution of BMI. The intraclass correlation coefficient (ICC) was used to compare tracking of the metrics. Metrics based on % distance (whether on the original or log scale) yielded higher ICCs compared with distance from median. The ICCs of the age-adjusted metrics were higher than that of the unadjusted metrics, particularly among children who were (1) overweight or had obesity, (2) younger and (3) followed for >3 years. The ICCs of the age-adjusted metrics were also higher compared with that of BMIz among children who were overweight or obese. Unlike BMIz, these alternative metrics do not have an upper limit and can be used for assessing BMI in all children, even those with very high BMIs. The age-adjusted % from median (on a log or linear scale) works well for all ages, while unadjusted % from median is better limited to older children or short follow-up periods.
Prior theory and research have linked negative appraisals (NA), emotion reactivity (ER), and cognitive reactivity (CR) to depression; however, few studies have examined whether even two of these constructs simultaneously, but none have done so in child or adolescent populations. A total of 571 youths (ages 9–13) completed a novel procedure in which all three constructs were assessed in response to the same personally relevant, hypothetical, peer victimization events. Multilevel modeling enabled the extraction of dynamic, within-person, latent-variable measures of NA, ER, and CR. All three constructs were related to children's depressive symptoms in ways that were commensurate with most (but not all) theoretical frameworks. Gender and age differences also emerged. Support for an NA-predicts-ER-predicts-CR model suggests ways that these constructs can be integrated into a more complete, transtheoretical understanding of the cognitive-emotional substrate of depression in children.
To those who pit Americans against immigrants and citizens against non-citizens, to those who scare peace-loving people with phantoms of lost liberty, my message is this: Your tactics only aid terrorists, for they erode our national unity and diminish our resolve. They give ammunition to America's enemies, and pause to America's friends.
The Brechin Lagerstätte (Katian, Ordovician) from the Lake Simcoe region of Ontario, Canada contains a diverse array of echinoderms. Here, we describe seven disparid and two hybocrinid crinoids (subclass Pentacrinoidea, infraclass Inadunata), including a new disparid species belonging to the Anomalocrinidae (order Homocrinida). In total, the disparids include Anomalocrinus astrictus n. sp.; Cremacrinus guttenbergensis Kolata, 1975; C. inaequalis Billings, 1859; Daedalocrinus bellevillensis Billings, 1883; Eustenocrinus springeri Ulrich, 1925; Iocrinus trentonensis Walcott, 1883; and Isotomocrinus tenuis Billings, 1857b. The hybocrinids include Hybocrinus tumidus Billings, 1857a and Hybocystites problematicus Wetherby, 1880. Previously known from only the holotype, three additional specimens of E. springeri expand our understanding of this unusual crinoid. Nomenclatural acts include: (1) the recommended designation of D. kirki Ulrich, 1925 as a junior synonym of D. bellevillensis is followed; (2) Hybocrinus pristinus Billings, 1858 is designated as a junior synonym of H. tumidus, and previous decisions are followed to retain Hybocystites eldonensis (Parks, 1908) as a junior synonym of H. problematicus; (3) although probably assignable to Anomalocrinus Meek and Worthen, 1865, the aberrant crinoid Glaucocrinus falconeri Parks and Alcock, 1912, and its genus Glaucocrinus Parks and Alcock, 1912, are designated as nomena dubia; (4) Iocrinus similis (Billings, 1857) is also designated as a nomen dubium; and (5) Iocrinus subcrassus torontoensis Fritz, 1925 is designated a junior synonym of I. subcrassus Meek and Worthen, 1865.
BACKGROUND: IGTS is a rare phenomenon of paradoxical germ cell tumor (GCT) growth during or following treatment despite normalization of tumor markers. We sought to evaluate the frequency, clinical characteristics and outcome of IGTS in patients in 21 North-American and Australian institutions. METHODS: Patients with IGTS diagnosed from 2000-2017 were retrospectively evaluated. RESULTS: Out of 739 GCT diagnoses, IGTS was identified in 33 patients (4.5%). IGTS occurred in 9/191 (4.7%) mixed-malignant GCTs, 4/22 (18.2%) immature teratomas (ITs), 3/472 (0.6%) germinomas/germinomas with mature teratoma, and in 17 secreting non-biopsied tumours. Median age at GCT diagnosis was 10.9 years (range 1.8-19.4). Male gender (84%) and pineal location (88%) predominated. Of 27 patients with elevated markers, median serum AFP and Beta-HCG were 70 ng/mL (range 9.2-932) and 44 IU/L (range 4.2-493), respectively. IGTS occurred at a median time of 2 months (range 0.5-32) from diagnosis, during chemotherapy in 85%, radiation in 3%, and after treatment completion in 12%. Surgical resection was attempted in all, leading to gross total resection in 76%. Most patients (79%) resumed GCT chemotherapy/radiation after surgery. At a median follow-up of 5.3 years (range 0.3-12), all but 2 patients are alive (1 succumbed to progressive disease, 1 to malignant transformation of GCT). CONCLUSION: IGTS occurred in less than 5% of patients with GCT and most commonly after initiation of chemotherapy. IGTS was more common in patients with IT-only on biopsy than with mixed-malignant GCT. Surgical resection is a principal treatment modality. Survival outcomes for patients who developed IGTS are favourable.
During the past decade, solar power has experienced transformative price declines, enabling it to grow to supply 1% of U.S. and world electricity. Addressing grid integration challenges, increasing grid flexibility, and further reducing cost will enable even greater potential for solar as an electricity source.
During the past decade, solar power has experienced transformative price declines, enabling it to become a viable electricity source that is supplying 1% of U.S. and world electricity. Further cost reductions are expected to enable substantially greater solar deployment, and new Department of Energy cost targets for utility-scale photovoltaics (PV) and concentrating solar thermal power are $0.03/kW h and $0.05/kW h by 2030, respectively. However, cost reductions are no longer the only significant challenge for PV—addressing grid integration challenges and increasing grid flexibility are critical as the penetration of PV electricity on the grid increases. The development of low cost energy storage is particularly synergistic with low cost PV, as cost declines in each technology are expected to support greater market opportunities for the other.
The Upper Ordovician (lower Katian) Bobcaygeon and Verulam formations from the Lake Simcoe region of Ontario contain a highly diverse echinoderm assemblage that is herein recognized as a Konservat-Lagerstätte. Although fossil crinoids have long been recognized from these formations, the fauna has not received a comprehensive taxonomic evaluation since Springer’s classic 1911 monograph. Recent extensive collection and preparation of new material from the Bobcaygeon and Verulam formations near Brechin, Ontario recovered numerous exceptionally preserved crinoid specimens with arms, stems, and attachment structures intact. The Brechin Lagerstätte is the most taxonomically diverse Katian crinoid fauna, with more than 20 crinoid genera represented in this collection.
Here, all dicyclic crinoids belonging to subclass Camerata from the Brechin Lagerstätte are evaluated. The following four genera and seven species are described from the fauna, including one new genus and four new species: Reteocrinus stellaris, Reteocrinus alveolatus, Archaeocrinus sundayae n. sp., Archaeocrinus maraensis n. sp., Priscillacrinus elegans n. gen. n. sp., Cleiocrinus regius, and Cleiocrinus lepidotus n. sp. The exceptional preservation of this collection provides an opportunity to describe more fully the morphologic and ontogenetic details of known Ordovician crinoid taxa, to conduct a taxonomic re-evaluation of many species, to describe new taxa, and to provide a framework for subsequent studies of crinoid community paleoecology.
The present study examined the energy (kilojoule) content of Australian fast-food menu items over seven years, before and after introduction of menu board labelling, to determine the impact of the introduction of the legislation.
Analysis of the median energy contents per serving and per 100g of fast-food menu items. Change in energy content of menu items across the years surveyed and differences in energy content of standard and limited-time only menu items were analysed.
Five of Australia’s largest fast food chains: Hungry Jack’s, KFC, McDonald’s, Oporto and Red Rooster.
All standard and limited-time only menu items available at each fast-food chain, collected annually for seven years, 2009–2015.
Although some fast-food chains/menu item categories had significant increases in the energy contents of their menus at some time points during the 7-year period, overall there were no significant or systematic decreases in energy following the introduction of menu labelling (P=0·19 by +17 kJ/100 g, P=0·83 by +8 kJ/serving). Limited-time only items were significantly higher in median energy content per 100 g than standard menu items (+74 kJ/100 g, P=0·002).
While reformulation across the entire Australian fast-food supply has the potential to positively influence population nutrient intake, the introduction of menu labelling legislation in New South Wales, Australia did not lead to reduced energy contents across the five fast-food chains. To encourage widespread reformulation by the fast-food industry and enhance the impact of labelling legislation, the government should work with industry to set targets for reformulation of nutrient content.
The nature of the fall-off at lower stresses from power-law behavior to a lower-order stress dependency is of particular interest in glacier and ice-sheet modeling. Preliminary experiments show that the stress level at which the fall-off occurs is a function of the specimen’s dislocation density. The analysis employs a dislocation-based model of anelasticity that provides a quantitative relationship between the effective dislocation density and the area of hysteresis loops observed in cyclic loading experiments. Combining this technique with a staged creep experiment makes it possible to calculate the dislocation density as a function of strain, thereby supporting a quantitative dislocation analysis of the deformation process.Work on saline ice established that the threshold stress associated with power-law behavior increased as a result of prior straining, power-law behavior emerged when the effective dislocation density increased measurably during deformation, and approximately linear behavior was evident when the dislocation density remained relatively constant. Those findings motivated the experiments on fresh-water ice presented here. The preliminary experiments show that pre-straining increases the stress associated with the fall-off from power-law behavior, and the results are interpreted in the context of a dislocation-based constitutive model developed for sea ice.
Experimental observations of the influence of particles at grain boundaries on the anelasticity and creep behavior of granular fresh-water ice are presented. Ice with particle contents of 0–4 wt.% was investigated under both reversed direct-stress and creep loading conditions at –12˚C. The results show that the particles decreased the grain-boundary relaxation by suppressing grain-boundary sliding at higher frequencies (10–1 to 101 Hz). In addition, the modulus increased by up to 30%, and the internal friction decreased by up to 30% at a frequency of 1 Hz. Staged creep tests showed that the particles affected the creep rate substantially. The minimum creep rate of ice containing 1 wt.% particles is 40% higher than that of particle-free ice, indicating that mechanisms besides dislocation glide aid the creep deformation.
The mechanical behavior and microstructural evolution of laboratory-prepared, particle-free fresh-water ice and ice with 1 wt.% (~0.43 vol.%) silt-sized particles were investigated under creep with a stress level of 1.45 MPa at −10°C. The particles were present both within the grains and along the grain boundaries. The creep rates of specimens with particles were always higher than those of particle-free ice. Dynamic recrystallization occurred for both sets of specimens, with new grains nucleating along grain boundaries in the early stages of creep. The ice with particles showed a higher nucleation rate. This resulted in a smaller average grain-size for the ice with particles after a given creep strain. Fabric studies indicated that ice with particles showed a more random orientation of c axes after creep to ~10% strain than the particle-free ice.