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| 1 | Global kinematics of tectonic plates and subduction zones since the late Paleozoic Era显示文摘Detailed global plate motion models that provide a continuous description of plate boundaries through time are an effective tool for exploring processes both at and below the Earth's surface. A new generation of numerical models of mantle dynamics pre-and post-Pangea timeframes requires global kinematic descriptions with full plate reconstructions extending into the Paleozoic(410 Ma). Current plate models that cover Paleozoic times are characterised by large plate speeds and trench migration rates because they assume that lowermost mantle structures are rigid and fixed through time. When used as a surface boundary constraint in geodynamic models, these plate reconstructions do not accurately reproduce the present-day structure of the lowermost mantle. Building upon previous work, we present a global plate motion model with continuously closing plate boundaries ranging from the early Devonian at 410 Ma to present day.We analyse the model in terms of surface kinematics and predicted lower mantle structure. The magnitude of global plate speeds has been greatly reduced in our reconstruction by modifying the evolution of the synthetic Panthalassa oceanic plates, implementing a Paleozoic reference frame independent of any geodynamic assumptions, and implementing revised models for the Paleozoic evolution of North and South China and the closure of the Rheic Ocean. Paleozoic(410-250 Ma) RMS plate speeds are on average ~8 cm/yr, which is comparable to Mesozoic-Cenozoic rates of ~6 cm/yr on average.Paleozoic global median values of trench migration trend from higher speeds(~2.5 cm/yr) in the late Devonian to rates closer to 0 cm/yr at the end of the Permian(~250 Ma), and during the Mesozoic-Cenozoic(250-0 Ma) generally cluster tightly around ~1.1 cm/yr. Plate motions are best constrained over the past 130 Myr and calculations of global trench convergence rates over this period indicate median rates range between 3.2 cm/yr and 12.4 cm/yr with a present day median rate estimated at~5 cm/yr. For Paleozoic times(410-251 Ma) our model results in median convergence rates largely~5 cm/yr. Globally,~90% of subduction zones modelled in our reconstruction are determined to be in a convergent regime for the period of 120-0 Ma. Over the full span of the model, from 410 Ma to 0 Ma,~93% of subduction zones are calculated to be convergent, and at least 85% of subduction zones are converging for 97% of modelled times. Our changes improve global plate and trench kinematics since the late Paleozoic and our reconstructions of the lowermost mantle structure challenge the proposed fixity of lower mantle structures, suggesting that the eastern margin of the African LLSVP margin has moved by as much as ~1450 km since late Permian times(260 Ma). The model of the plate-mantle system we present suggests that during the Permian Period, South China was proximal to the eastern margin of the African LLSVP and not the western margin of the Pacific LLSVP as previous thought. | Alexander Young Nicolas Flament Kayla Maloney Simon Williams Kara Matthews Sabin Zahirovic R.Dietmar Müller | 2019 | Geoscience Frontiers2019，10，3： | 10 |
| 2 | Linking tree growth rate, damage repair, and susceptibility to a genus-specific pest infestation显示文摘Pest preference and subsequent susceptibility of a host individual is likely related to previous growth patterns in that host.Emerald ash borer(Agrilus planipennis Fairmaire)is a pestiferous beetle introduced to North America from Asia.While all species of ash are susceptible to attack,some individual trees appear to survive infestation.We selected ash trees in southeastern Michigan,collected cores and categorized trees as high tolerance to emerald ash borer attack(high overall health,low crown dieback),low tolerance(low overall health,high crown dieback)and intermediate tolerance(in-between the other categories).We artificially wounded trees and measured wound closure after 3 years.Ring width indices were not correlated between high and low tolerance trees.Regression slopes comparing growth and years were significantly different between the three tolerance categories,with high tolerance trees having the steepest slope.Wound closure was greatest in high tolerance trees.High tolerance trees demonstrating more rapid(steeper regression slope),consistent(lower variance),and effective(greater wound closure)growth.Those vigorously growing trees likely had more capacity to repair damage caused by emerald ash borer,leading to healthier trees in our categorization.Linking previous host growth patterns to health may have implications related to identifying individual trees potentially tolerant to attack. | Kayla N.Boyes Kathryn G.Hietala-Henschell Alexander P.Barton Andrew J.Storer Jordan M.Marshall | 2019 | Journal of Forestry Research2019，30，5： | 1 |
| 3 | Short-term, daily intake of yogurt containing Bifidobacterium animalis ssp . lactis Bf-6 (LMG 24384) does not affect colonic transit time in women显示文摘 | Daniel J. Merenstein Frank D’Amico Caren Palese Alexander Hahn Jessy Sparenborg Tina Tan Hillary Scott Kayla Polzin Lore Kolberg Robert Roberts | 2013 | British Journal of Nutrition2013，，2： | 1 |
| 4 | The mechanisms of color production in black skin versus red skin on the heads of New World vultures显示文摘A determination of how the color of animal integument is produced is a starting point for investigations into the function and evolution of coloration.The mechanisms that give rise to the color of bare skin of New World vultures are largely unexplored.Here,we investigate the source of color production in the bare skin of Turkey Vultures(Cathartes aura)and Black Vultures(Coragyps atratus).Using UV-vis reflectance spectroscopy,we found evidence that hemoglobin is the primary pigment responsible for the red coloration of the bare skin on the heads of Turkey Vultures,and that eumelanin is responsible for the black coloration of the bare skin on the heads of Black Vultures.Light microscopy of incisional skin samples further supported these mechanisms of color production by revealing the presence of numerous blood vessels near the surface of the Turkey Vulture skin,and a high concentration of melanosomes in the skin of Black Vultures.Using high performance liquid chromatography(HPLC),we detected carotenoids within the skin of both species with significantly higher total concentrations of carotenoids in the skin of Turkey Vultures compared to the skin of Black Vultures.The carotenoids detected were dietary carotenoids that typically produce yellow coloration when accumulated in integument and were present in low concentrations.We hypothesize that the dietary carotenoids present do not contribute to the color of the skin,but rather help to compensate for the lack of melanosomes found in Turkey Vulture skin.The presence of additional carotenoids may act as an antioxidant to minimize UV damage when the bare Turkey Vulture head skin is exposed to direct sunlight for prolonged periods of time when soaring and scavenging for food. | Nicholas M.Justyn Matthew J.Powers Geoffrey E.Hill Kayla Alexander Adrián Naveda-Rodríguez Scott A.Rush | 2023 | Avian Research2023，14，1： | 0 |
| 5 | Emergency department management of acute agitation in the reproductive age female and pregnancy显示文摘BACKGROUND:Agitation is a common presentation within emergent departments(EDs).Agitation during pregnancy should be treated as an obstetric emergency,as the distress may jeopardize both the patient and fetus.The safety of psychotropic medications in the reproductive age female has not been well established.This review aimed to explore a summary of general agitation recommendations with an emphasis on ED management of agitation during pregnancy.METHODS:A literature review was conducted to explore the pathophysiology of acute agitation and devise a preferred treatment plan for ED management of acute agitation in the reproductive age or pregnant female.RESULTS:While nonpharmacological management is preferred,ED visits for agitation often require medical management.Medication should be selected based on the etiology of agitation and the clinical setting to avoid major adverse effects.Adverse effects are common in pregnant females.For mild to moderate agitation in pregnancy,diphenhydramine is an effective sedating agent with minimal adverse effects.In moderate to severe agitation,high-potency typical psychotropics are preferred due to their neutral effects on hemodynamics.Haloperidol has become the most frequently utilized psychotropic for agitation during pregnancy.Second generation psychotropics are often utilized as second-line therapy,including risperidone.Benzodiazepines and ketamine have demonstrated adverse fetal outcomes.CONCLUSION:While randomized control studies cannot be ethically conducted on pregnant patients requiring sedation,animal models and epidemiologic studies have demonstrated the effects of psychotropic medication exposure in utero.As the fetal risk associated with multiple doses of psychotropic medications remains unknown,weighing the risks and benefits of each agent,while utilizing the lowest effective dose remains critical in the treatment of acute agitation within the EDs. | Ariella Gartenberg Kayla Levine Alexander Petrie | 2024 | World Journal of Emergency Medicine2024，15，2： | 0 |
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