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Did natural fission of^(235)U in the earth lead to formation of the supercontinent Columbia?

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Geoscience Frontiers 2012年第4期3卷 369-374页

作者： john j.W.rogers Department of Geological Sciences University of North Carolina at Chapel HillChapel HillNC 27599-3315USA

Steady decline in the percentage of 235U in terrestrial uranium made natural fission impos- sible after about 1.8 Ga. Fission before 1.8 Ga disturbed the lead isotope system at various places world- wide, such as Oklo, Gabon, and may have caused the first lead isotope paradox. Fission in areas of high uranium concentration may also have generated enough heat to localize sparse Archean and Paleoproter- ozoic UHT belts. The oldest widespread orogenic systems formed at approximately 2.0-1.8 Ga after fission stopped contributing to the earth＇s heat flow. These early orogenic systems partly created the supercontinent Columbia.

关键词： Natural fission Archean Paleoproterozoic Columbia supercontinent Tectonics

Using Twitter Bios to Measure Changes in Self-Identity:Are Americans Defining Themselves More Politically Over Time?

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journal of Social Computing 2021年第1期2卷 1-13页

作者： Nick rogers jason j.jones Department of Sociology Stony Brook UniversityStony BrookNY 11794USA

Are Americans weaving their political views more tightly into the fabric of their self-identity over time?If so,then we might expect partisan disagreements to continue becoming more emotional,tribal,and *** recent scholarship has speculated that this politicization of Americans’identity is occurring,but there has been little compelling attempt to quantify the phenomenon,largely because the concept of identity is notoriously difficult to *** introduce here a methodology,Longitudinal Online Profile Sampling(LOPS),which affords quantifiable insights into the way individuals amend their identity over *** this method,we analyze millions of“bios”on the microblogging site Twitter over a 4-year span,and conclude that the average American user is increasingly integrating politics into their social *** on the site are adding political words to their bios at a higher rate than any other category of words we measured,and are now more likely to describe themselves by their political affiliation than their religious *** data suggest that this is due to both cohort and individual-level effects.

关键词： identity social identity theory social media ideology political polarization Twitter

Overcoming maladaptive plasticity through plastic compensation

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Current Zoology 2013年第4期59卷 526-536页

作者： Matthew R.j. MORRIS Sean M. rogers Department of Biological Sciences University of Calgary Calgary AB Canada T2N 1N4

Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plas- ticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes （standing genetic variation, genetic compensation） and two of which do not （standing epigenetic variation, plastic compensation）. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for under- standing evolutionary change

关键词： Homeostasis Canalization Ecological speciation Standing genetic variation Genetic compensation Countergradi-ent variation

Integrated nanoelectronic-photonic devices and bioresorbable materials

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Nano Research 2021年第9期14卷 2885-2887页

作者： john A.rogers Departments of Materials Science and Engineering Biomedical Engineering and Neurological SurgerySimpson Querrey Institute for BioelectronicsNorthwestern UniversityEvanstonIL 60208USA

I am honored receive,with ***,this years Nano Research *** my case,the recognition is largely an acknowledgement of the scientific advances achieved by a diverse set of graduate students,undergraduates and postdoctoral fellows as they passed through my group over the years-talented,dedicated,creative,collaborative people,of the very highest *** of these former group members,each now leading large and highly successful academic research programs of their own,contributed outstanding articles to this special issue-21 in total!I would like to extend my special thanks to them-I feel a strong sense of pride and joy in their many impressive accomplishments as pioneering,independent *** topics of these articles span a wide range,as a powerful set of projects at the forefront of nanoscience and nanotechnology,briefly summarized by topic area in the following.

关键词： electronic accomplishment summarized

Myeloid sarcoma presenting as a colon polyp and harbinger of chronic myelogenous leukemia

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World journal of Gastrointestinal Oncology 2016年第3期8卷 321-325页

作者： Robert rogers mark Ettel Margaret Cho Alexander Chan Xiao-jun Wu Antonio G Neto Department of Pathology New York University School of Medicine Department of Pathology Memorial Sloan Kettering Cancer Center Department of Pathology George Washington University School of Medicine

Myeloid sarcoma, also known as granulocytic sarcoma or chloroma is an unusual accumulation of malignant myeloid precursor cells in an extramedullary site, which disrupts the normal architecture of the involved tissue. It is known to occur more commonly in patients with acute myelogenous leukemia and less commonly in those with myelodysplastic syndrome and myeloproliferative neoplasm, such as chronic myelogenous leukemia. The most common sites of involvement include bone, skin and lymph nodes. However, rare cases have been reported in the gastrointestinal tract, genitourinary tract, or breast. Most commonly, a neoplastic extramedullary proliferation of myeloid precursors in a patient would have systemic involvement of a myeloid neoplasm, including in the bone marrow and peripheral blood. Infrequently, extramedullary disease may be the only site of involvement. It may also occur as a localized antecedent to more generalized disease or as a site of recurrence. Herein, we present the first case in the English literature of a patient presenting with an isolated site of myeloid sarcoma arising in the form of a colonic polyp which, after subsequent bone marrow biopsy, was found to be a harbinger of chronic myelogenous leukemia.

关键词： Myeloid sarcoma Granulocytic sarcoma Chloroma Chronic myelogenous leukemia

Distributed Secondary Control Based on Dynamic Diffusion Algorithm for Current Sharing and Average Voltage Regulation in DC Microgrids

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journal of Modern Power Systems and Clean Energy 2024年第2期12卷 597-607页

作者： Dawei Liao Fei Gao Daniel j.rogers Wentao Huang Dong Liu Houjun Tang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Engineering Science University of OxfordOxford OX12JDU.K. IEEE

This paper introduces a distributed secondary control scheme for achieving current sharing and average voltage regulation objectives in a DC *** proposed scheme employs a dynamic diffusion algorithm(DDA)instead of the consensus algorithm to enable distributed communication among *** help understand DDA,the relation of DDA and other diffusion algorithms is discussed in detail and its superiority is shown by comparison with diffusion and consensus ***,considering the discrete nature and different sampling time of the digital controller and communication network,a z-domain model of the entire DC microgrid is *** influence of communication and secondary control parameters on the system stability is *** on the established model,the tolerable communication rates are ***-time simulations conducted on the OPAL-RT platform validate the effectiveness of the proposed scheme,showcasing its advantages in terms of convergence speed and stability.

关键词： Cooperative control DC microgrid diffusion algorithm discrete-time modeling distributed secondary control

Calling underwater is a costly signal： size-related differences in the call rates of Antarctic leopard seals

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Current Zoology 2017年第4期63卷 433-443页

作者： Tracey L. rogers Evolution & Ecology Research Centre School of BEES University of New South Wales Sydney Sydney NSW2052 Australia

It is proposed that where sexually selected vocal communication is an honest signal, the call production rate is predicted to change throughout the breeding season. Male leopard seals call underwater for many hours each day over their three- to four-month breeding season, and it is hypothesized that a decrease in calling rate would be associated with the declining body condition of smaller males. The calling rates of leopard seals were measured （N= 49 recordings） and com- pared between seals of different size classes throughout the breeding season. Male leopard seals produce their calls at more stable rates as they become larger. In this study, larger male leopard seals adopted a strategy of consistent underwater calling throughout the breeding season, whereas there was a breakdown in the calling stereotypy of the smaller males at its height. Toward the end of the breeding season, the smaller seals produced fewer calls in shortened calling bouts, and they took more rest periods. Therefore, underwater calling may represent an honest signal in the leopard seal. For marine mammals that call underwater, the production of repetitive sequences advertises the breath-holding ability of the caller to the listeners, and this ability may be related to male stamina and endurance, thus representing an honest signal that could be widespread in other species.

关键词： acoustic cues costly signaling display behavior honest advertisement marine mammals vocalizations.

Organic conjugated polymers and polymer dots as photocatalysts for hydrogen production

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Frontiers in Energy 2021年第3期15卷 667-677页

作者： Saket MATHUR Benjamin rogers Wei WEI Mechanical Engineering Department Wichita State UniversityWichita KS 67260USA

Owing to the outstanding characteristics of tailorable electronic and optical properties,semiconducting polymers have attracted considerable attention in recent *** them,organic polymer dots process large breadth of potential synthetic diversity are the representative of photocatalysts for hydrogen production,which presents both an opportunity and a *** this mini-review,first,the organic polymer photocatalysts were ***,recent reports on polymer dots which showed a superior photocatalytic activity and a robust stability under visible-light irradiation,for hydrogen production were ***,challenges and outlook on using organic polymer dots-based photocatalysts from hydrogen production were discussed.

关键词： polymer dots(Pdots) photocatalysis hydrogen production

SIMULATION OF COMPLEX THERMOMECHANICAL FATIGUE

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 400-406页

作者： R.Bardenheier G.rogers Instron Ltd. Servohydraulic Business Team High Wycombe HP12 3SY United KingdomInstron Ltd. Servohydraulic Business Team High Wycombe HP12 3SY United Kingdom

Two different types of experimental techniques to perform non-isothermal, uniax-ial and biaxial fatigue tests were described. A new miniaturised electrothermal-mechanical test rig was presented and discussed. It enables testing of small specimens under complex thermomechanical loading conditions. In order to cope with the simulation of well defined biaxial proportional and non-proportional loadings with in-phase and out-of-phase superposition of thermal loads a cruciform biaxial fatigue testing machine has been developed. Special design features of both machines, and the specimens tested, as well as typical test results were discussed.

关键词： thermomechanical fatigue biaxial loading non-proportional loading cruciform fatigue testing machine miniaturised test rig