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Ionospheric longitudinal variations at midlatitudes: Incoherent scatter radar observation at Millstone Hill

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Science China(Technological Sciences) 2012年第5期55卷 1153-1160页

作者： COSTER Anthea HOLT John FOSTER John erickson Phil MIT Haystack Observatory Off Route 40 Westford MA 01866 USA

Incoherent scatter radar （ISR） extra-wide coverage experiments during the period of 1978-2011 at Millstone Hill are used to investigate longitudinal differences in electron density. This work is motivated by a recent finding of the US east-west coast difference in TEC suggesting a combined effect of changing geomagnetic declination and zonal winds. The current study pro- vides strong supporting evidence of the longitudinal change and the plausible mechanism by examining the climatology of electron density Ne on both east and west sides of the radar with a longitude separation of up to 40% for different heights within 300-450 kin. Main findings include： 1） The east-west difference can be up to 60% and varies over the course of the day, being positive （East side Ne 〉 West side Ne） in the late evening, and negative （West side Ne 〉 East side Ne） in the pre-noon. 2） The east-west difference exists throughout the year. The positive （relative） difference is most pronounced in winter; the negative （relative） difference is most pronounced in early spring and later summer. 3） The east-west difference tends to enhance toward decreasing solar activity, however, with some seasonal dependence; the enhancements in the positive and negative differences do not take place simultaneously. 4） Both times of largest positive and largest negative east-west differences in Ne are earlier in summer and later in winter. The two times differ by 12-13 h, which remains constant throughout the year. 5） Variations at different heights from 300-450 km are similar. Zonal wind climatology above Millstone Hill is found to be perfectly consistent with what is expected based on the electron density difference between the east and west sides of the site. The magnetic declination-zonal wind mechanism is true for other longitude sectors as well, and may be used to understand longitudinal variations elsewhere. It may also be used to derive thermospheric zonal winds.

关键词： midlatitude ionosphere geomagnetic declination thermospheric zonal winds longitudinal variation incoherent scatterradar

Rehabilitation and return to sport after hamstring strain injury

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Journal of Sport and Health Science 2017年第3期6卷 262-270页

作者： Lauren N.erickson Marc A.Sherry Sports Rehabilitation University of Wisconsin Hospital and ClinicsMadisonWI 53718USA

Hamstring strain injuries are common among sports that involve sprinting,kicking,and high-speed skilled movements or extensive muscle lengthening-type maneuvers with hip flexion and knee *** injuries present the challenge of significant recovery time and a lengthy period of increased susceptibility for recurrent *** one third of hamstring strains recur within the first year following return to sport with subsequent injuries often being more severe than the *** high re-injury rate suggests that athletes may be returning to sport prematurely due to inadequate return to sport *** this review article,we describe the epidemiology,risk factors,differential diagnosis,and prognosis of an acute hamstring *** on the current available evidence,we then propose a clinical guide for the rehabilitation of acute hamstring strains and an algorithm to assist clinicians in the decision-making process when assessing readiness of an athlete to return to sport.

关键词： Acute Muscle Performance Physical therapy Recurrence Re-injury Thigh

A Flexible Boundary Procedure for Hyperbolic Problems: Multiple Penalty Terms Applied in a Domain

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Communications in Computational Physics 2014年第7期16卷 541-570页

作者： Jan Nordstrom Qaisar Abbas Brittany A.erickson Hannes Frenander Department of Mathematics Division of Computational MathematicsLinkoping UniversitySE-58183 Link¨opingSweden Department of Information Technology Division of Scientific ComputingUppsala UniversitySE-75105 UppsalaSweden Department of Geological Sciences San Diego State UniversitySan DiegoCA 92182-1020USA Department of Mathematics Division of Computational MathematicsLinkoping UniversitySE-58183 Link¨opingSweden.

A new weak boundary procedure for hyperbolic problems is *** consider high order finite difference operators of summation-by-parts form with weak boundary conditions and generalize that *** new boundary procedure is applied near boundaries in an extended domain where data is *** show how to raise the order of accuracy of the scheme,how to modify the spectrum of the resulting operator and how to construct non-reflecting properties at the *** new boundary procedure is cheap,easy to implement and suitable for all numerical methods,not only finite difference methods,that employ weak boundary *** results that corroborate the analysis are presented.

关键词： Summation-by-parts weak boundary conditions penalty technique high-order accuracy finite difference schemes stability steady-state non-reflecting boundary conditions

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Soft-Power Safari

Beijing Review 2014年第32期57卷 46-47页

作者： Dane erickson the University of Colorado Peking university

Focus of U.S.-Africa Leaders Summit on cooperation, not competition, with China

关键词：中国经济经济建设经济合作经济增长

How can you trace your family tree online？

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空中英语教室（高级版．彭蒙惠英语） 2016年第3期 24-25,44页

作者： Melissa erickson

A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin

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Chinese Science Bulletin 2009年第3期54卷 430-435页

作者： XU Xing ZHAO Qi NORELL Mark SULLIVAN Corwin HONE David erickson Gregory WANG XiaoLin HAN FengLu GUO Yu Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China American Museum of Natural History Central Park West at 79th Street NY 10024 USA Department of Biological Science Florida State University Tallahassee Florida 32306-1100 USA Graduate University of Chinese Academy of Sciences Beijing 100049 China

Recent fossil discoveries have substantially reduced the morphological gap between non-avian and avian dinosaurs, yet avians including Archaeopteryx differ from non-avian theropods in their limb proportions. In particular, avians have proportionally longer and more robust forelimbs that are capable of supporting a large aerodynamic surface. Here we report on a new maniraptoran dinosaur, Anchiornis huxleyi gen. et sp. nov., based on a specimen collected from lacustrine deposits of uncertain age in western Liaoning, China. With an estimated mass of 110 grams, Anchiornis is the smallest known non-avian theropod dinosaur. It exhibits some wrist features indicative of high mobility, presaging the wing-folding mechanisms seen in more derived birds and suggesting rapid evolution of the carpus. Otherwise, Anchiornis is intermediate in general morphology between non-avian and avian dinosaurs, particularly with regard to relative forelimb length and thickness, and represents a transitional step toward the avian condition. In contrast with some recent comprehensive phylogenetic analyses, our phylogenetic analysis incorporates subtle morphological variations and recovers a conventional result supporting the monophyly of Avialae.

关键词：白垩纪恐龙古生物关节进化

Sustainable Management of Eutrophic Lakes and Reservoirs

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Journal of Environmental Protection 2017年第4期8卷 436-463页

作者： Tyler Wagner Larry E. erickson Department of Chemical Engineering Kansas State University Manhattan Kansas USA

Eutrophication of lakes and reservoirs is a major water quality problem that poses significant environmental, economic and social threats around the world. Monitoring and managing lakes and reservoirs to prevent or limit eutrophication, therefore, has significant value. The literature has been reviewed to study ecological engineering and management methods that have been and can be applied to improve water quality. Ecological engineering has the potential to be utilized to improve the design and operation of lakes and reservoirs through monitoring and active management of biological, chemical and physical components. Phosphorus concentrations can be reduced by effective and sustainable management practices to improve water quality.

关键词： Eutrophication Harmful Algal Blooms Cyanobacteria Ecological Engineering Biomanipulation

A More Renewable-Friendly Electrical Grid: Thermal Storage Refrigeration for Demand Response in California and Denmark

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Smart Grid and Renewable Energy 2012年第4期3卷 316-323页

作者： kurt kornbluth John Cook Paul erickson Agriculture and Resource Economics University of California Davis USA Department of Mechanical Engineering University of California Davis USA Program for International Energy Technologies University of California Davis USA

Energy storage technologies, which enable demand response, are being explored throughout the world as a component of strategies for switching to renewable intermittent energy sources and reducing peak loads. This study examines thermal storage refrigeration (TSR) technology as a case study for the potential value of demand response in California and Denmark. Using technical specifications from a TSR prototype developed at UC Davis and market data from California and Denmark, the analysis examines possible business models for the TSR refrigerators and highlights market characteristics that are important to its adoption. Results suggest that the TSR technology is not a viable option in the current market environment in Denmark, but could payback in less than 6 years in California if a part of a demand response based virtual power plant. In a hypothetical future scenario involving real-time pricing in the retail market, a high degree of price volatility would be needed to make TSR technology appealing to residential consumers. Based on this analysis, an interesting area of future work would focus on the market potential of TSR technology for commercial and industrial applications.

关键词： Refrigeration Demand-Response Thermal Storage Wind Energy California Denmark Electricity Grid

The impact of COVID-19 on clinical outcomes of burn patients

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Burns & Trauma 2023年第1期11卷 792-799页

作者： Elliot T.Walters Alen Palackic Camila Franco-Mesa Nikhil R.Shah Michael J.erickson Steven E.Wolf Department of Surgery University of Texas Medical Branch301 UniversityGalvestonTXUSA Division of Plastic Aesthetic and Reconstructive SurgeryDepartment of SurgeryMedical University of GrazGrazAustria

Background:Multiple studies have shown the SARS-CoV-2 virus(COVID-19)to be associated with deleterious outcomes in a wide range of *** impact of COVID-19 has not been well investigated among burned *** suspect that patients will have worsened respiratory and thrombotic complications,ultimately leading to increased *** objective of this study is to determine the impact a concurrent infection of COVID-19 has on clinical outcomes after a burn ***:This is a retrospective,propensity matched,cohort *** examined a de-identified database of electronic medical records of over 75 million patients across 75 health care associations in the United States for patients treated for thermal burns from 1 January 2020,to 31 July 2021,and those who also were diagnosed with COVID-19 infection within one day before or after injury based on International Classification of Disease,tenth revision(ICD-10)*** participants included adults who were treated for a burn injury during the study ***:We included 736 patients with burn injury and concomitant COVID-19 infection matched to 736 patients with burn injury and no concurrent COVID-19 infection(total 1472 patients,mean age 36.3±24.3).We found no significant increase in mortality observed for patients with concurrent COVID-19(OR 1.203,95%CI 0.517-2.803;p=0.6675).We did observe significant increase in infections(OR 3.537,95%CI 2.798-4.471;p=0.0001),thrombotic complications(OR 2.342,95%CI 1.351-4.058;p=0.0018),as was the incidence of hypertrophic scarring(OR 3.368,95%CI 2.326-4.877;p=0.0001).Conclusions:We observed that concurrent COVID-19 infection was associated with an increase in infections,thrombosis and hypertrophic scarring but no increase in mortality in our cohort of burn patients.

关键词： COVID-19 infection mortality burn thrombosis scarring