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Photoionisation detection of a single Er3+ ion with sub-100-ns time resolution

National Science Review 2024年第4期11卷 38-45页

作者： Yangbo Zhang Wenda Fan Jiliang Yang Hao Guan Qi Zhang Xi Qin changkui Duan Gabriele G.de Boo Brett c.Johnson jeffrey c.mc callum Matthew J.Sellars Sven Rogge chunming Yin Jiangfeng Du cAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of China cAS center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China centre of Excellence for Quantum computation and communication Technology School of Physics University of New South Wales centre of Excellence for Quantum computation and communication Technology School of Engineering RMIT University centre of Excellence for Quantum computation and communication Technology School of Physics University of Melbourne centre of Excellence for Quantum computation and communication Technology Research School of Physics and Engineering Australian National University

Efficient detection of single optical centres in solids is essential for quantum information processing, sensing and single-photon generation *** this work,we use radio-frequency（RF） reflectometry to electrically detect the photoionisation induced by a single Er3+ion in *** high bandwidth and sensitivity of the RF reflectometry provide sub-100-ns time resolution for the photoionisation *** this technique,the optically excited state lifetime of a single Er3+ion in a Si nano-transistor is measured for the first time to be 0.49±0.04μ*** results demonstrate an efficient approach for detecting a charge state change induced by Er excitation and *** approach could be used for fast readout of other single optical centres in solids and is attractive for large-scale integrated optical quantum systems thanks to the multi-channel RF reflectometry demonstrated with frequency multiplexing techniques.

关键词： single optical centres erbium ions RF reflectometry photoionisation detection

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Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

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Journal of Animal Science and Biotechnology 2015年第2期6卷 163-176页

作者： jeffrey L Vallet Anthony K mc Neel Jeremy R Miles Bradley A Freking U.S. Department of Agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

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Reimagining large river management using the Resist–Accept–Direct(RAD) framework in the Upper Mississippi River

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Ecological Processes 2023年第4期12卷 3-22页

作者： Nicole K.Ward Abigail J.Lynch Erik A.Beever Joshua Booker Kristen L.Bouska Holly Embke jeffrey N.Houser John F.Kocik Joshua Kocik David J.Lawrence Mary Grace Lemon Doug Limpinsel Madeline R.Magee Bryan M.Maitland Owen mc Kenna Andrew Meier John M.Morton jeffrey D.Muehlbauer Robert Newman Devon c.Oliver Heidi M.Rantala Greg G.Sass Aaron Shultz Laura M.Thompson Jennifer L.Wilkening National Park Service Climate Change Response Program Habitat conservation Division NOAA Wisconsin Department of Natural Resources Aquatic Sciences center Center for Limnology U.S. Geological Survey Northern Prairie Wildlife Research Center and Midwest Climate Adaptation Science Center U.S. Army corps of Engineers Alaska Wildlife Alliance U.S. Geological Survey Alaska Cooperative Fish and Wildlife Research Unit University of Alaska Fairbanks University of North Dakota Great Lakes Indian Fish and Wildlife commission (GLIFWc) Minnesota Department of Natural Resources U.S. Geological Survey National Climate Adaptation Science Center and School of Natural Resources University of Tennessee U.S. Geological Survey National Climate Adaptation Science Center U.S. Geological Survey Northern Rocky Mountain Science Center Department of Ecology Montana State University U.S. Fish and Wildlife Service National Wildlife Refuge System U.S. Geological Survey Upper Midwest Environmental Sciences Center U.S. Geological Survey Midwest Climate Adaptation Science Center NOAA NEFSc Orono University of Nebraska-Lincoln

Background Large-river decision-makers are charged with maintaining diverse ecosystem services through unprecedented social-ecological transformations as climate change and other global stressors intensify. The interconnected, dendritic habitats of rivers, which often demarcate jurisdictional boundaries, generate complex management challenges. Here, we explore how the Resist–Accept–Direct(RAD) framework may enhance large-river management by promoting coordinated and deliberate responses to social-ecological trajectories of change. The RAD framework identifies the full decision space of potential management approaches, wherein managers may resist change to maintain historical conditions, accept change toward different conditions, or direct change to a specified future with novel conditions. In the Upper Mississippi River System, managers are facing social-ecological transformations from more frequent and extreme high-water events. We illustrate how RAD-informed basin-, reach-, and site-scale decisions could:(1) provide cross-spatial scale framing;(2) open the entire decision space of potential management approaches; and(3) enhance coordinated inter-jurisdictional management in response to the trajectory of the Upper Mississippi River *** The RAD framework helps identify plausible long-term trajectories in different reaches(or subbasins) of the river and how the associated social-ecological transformations could be managed by altering site-scale conditions. Strategic reach-scale objectives may reprioritize how, where, and when site conditions could be altered to contribute to the basin goal, given the basin's plausible trajectories of change(e.g., by coordinating action across sites to alter habitat connectivity, diversity, and redundancy in the river mosaic).conclusions When faced with long-term systemic transformations(e.g., > 50 years), the RAD framework helps explicitly consider whether or when the basin vision or goals may no longer be achievable,

关键词： Ecosystem Management Transformation Social-ecological system Anthropocene climate change Basin planning cross-scale interactions

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The chapman-Richards Distribution and its Relationship to the Generalized Beta

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Forest Ecosystems 2019年第3期6卷 219-235页

作者： jeffrey H.Gove Thomas B.Lynch Mark J.Ducey USDA Forest Service Northern Research Station271 Mast Road Durham 03824NHUSA Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA Department of Natural Resources and the Environment University of New Hampshire114 James Hall Durham 03824NHUSA

Background: The chapman-Richards distribution is developed as a special case of the equilibrium solution to the mcKendrick-Von Foerster equation. The chapman-Richards distribution incorporates the vital rate assumptions of the chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distribution. Therefore, unlike 'assumed' distribution models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the chapman-Richards distribution can be recast as a subset of the generalized beta distribution of the first kind, a rich family of assumed probability distribution models with known properties. These known properties for the generalized beta are then immediately available for the chapman-Richards distribution, such as the form of the compatible basal area-size distribution. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possible distribution shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilibrium assumption. The parameter estimates are shown to depend on both the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat by distribution shape, with the smaller, noisier samples providing less reliable estimates of the vital rates and final distribution forms. conclusions: The chapman-Richards distribution in its original form, or recast as a generalized beta form, presents a potentially useful model integrating vital rates and stand diameters into a flexible family of resultant distributions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are obtained.

关键词： Diameter distributions chapman-Richards growth Generalized beta distribution of the first kind Maximum likelihood mcKendrick-Von Foerster equation Physiologically structured population model Size-structured distributions

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FERROTAAFFEITE-2N2S,A NEW MINERAL SPEcIES,AND THE cRYSTAL STRUcTURE OF Fe2+-RIcH MAGNESIOTAAFFEITE-2N'2S FROM THE XIANGHUALING TIN-POLYMETALLIc ORE FIELD,HUNAN PROVINcE,cHINA

FERROTAAFFEITE-2N2S,A NEW MINERAL SPECIES,AND THE CRYSTAL ST...

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中国科学院地质与地球物理研究所2012年度（第12届）...

作者： ZHUMING YANG KUISHOU DING jeffrey DE FOURESTIER QIAN MAO HE LI Key Laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences

Ferrotaaffeite-2N’2S,ideally BeFeAlO with hexagonal symmetry P6mc,is a new mineral species of the taaffeite group(IMA No,2011-025) occurring as a skarn mineral in the Xianghualing Sn-polymetallic ore field,Linwu county,Hunan Province,People’s Republic of *** was found near the outer contact of the Laizhiling A-type granite pluton and in the Middle-Upper Devonian carbonate rocks of the Qiziqiao *** associated minerals are Fe-rich magnesiotaaffeite- 2N’2S,ferronigerite-2N1s,cassiterite,liberite,pyrite,sphalerite,pyrrhotite,galena,spinel,and *** mineral forms tabular crystals about 100μm in *** is dark green to dark grey with a white streak,transparent,and has a vitreous lustre. cleavage is fair on {001}.It is brittle,with a conchoidal *** hardness is VHN 1801-2404 kg/mm(8.5-9 on the Mohs scale).No fluorescence in long- or short-wave ultraviolet radiation was *** calculated density from the empirical chemical formula is 3.99 g/*** Gladstone-Dale relationship gives N= *** empirical formula for the investigated ferrotaaffeite-2N’2S is Be(FeMgZnMnSn)AlO,.The simplified formula is Be(Fe,Mg,Zn)*** strongest five reflections in the X-ray powder diffraction pattern[d in A(I) hkl]are:2.43(100) 114,2.60(90) 016,1.425(90)220, 2.86(80) 110,and 1.473(80) *** unit-cell parameters refined from the powder data are a 5.706(8),c 18.352(3) A,and V 517.46(8) ,Z = *** associated Fe-rich magnesiotaaffeite-2N’2S has empirical formula Be(MgFeZnMn Sn)*** structure was solved and refined in space group P6mc,with a 5.6978(8),b 5.6978(8),c 18.373(4) A, 7516.57(15) ,to R = 0.043,wR = 0.137.

关键词： ferrotaaffeite-2N’2S new mineral species magnesiotaaffeite-2N’2S’ taaffeite group Xianghualing tin mine Tanzanian LM felsic inaginatisin china

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Antecedents and sex/gender differences in youth suicidal behavior

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World Journal of Psychiatry 2014年第4期4卷 120-132页

作者： Anne E Rhodes Michael H Boyle jeffrey A Bridge Mark Sinyor Paul S Links Lil Tonmyr Robin Skinner Jennifer M Bethell corine carlisle Sarah Goodday Travis Salway Hottes Amanda Newton Kathryn Bennett Purnima Sundar Amy H cheung Peter Szatmari Institute for clinical Evaluative Sciences Toronto M4N 3M5 Ontario Canada Department of Psychiatry University of Toronto Toronto M5T 1R8 Ontario Canada Suicide Studies Unit St. Michael’s Hospital Toronto M5B 1W8 Ontario Canada Dalla Lana School of Public Health University of Toronto Toronto M5T 3M7 Ontario Canada Department of Psychiatry and Behavioural Neurosciences Mc Master University Hamilton L8N 3K7 Ontario Canada The Offord centre for child Studies Hamilton L8S 4K1 Ontario Canada The Research Institute at Nationwide children’s Hospital Columbus OH 43205 United States The Ohio State University college of Medicine Columbus OH 43210 United States Sunnybrook Health Sciences centre Toronto M4N 3M5 Ontario Canada Department of Psychiatry University of Western Ontario London N6A 5W9 Ontario Canada The Injury and child Maltreatment Section Public Health Agency of Canada Ottawa K1A 0K9 Ontario Canada The centre for Addiction and Mental Health Toronto M6J 1H4 Ontario Canada Department of Pediatrics University of Alberta Edmonton Alberta T6G 1C9 Canada The Department of clinical Epidemiology and Biostatistics Mc Master University Hamilton L8S 4K1 Ontario Canada The Ontario centre of Excellence for child and Youth Mental Health Ottawa K1G 0Z1 Ontario Canada The Hospital for Sick children Toronto M5G 1X8 Ontario Canada

Suicide is the second leading cause of death in youth globally; however, there is uncertainty about how best to intervene. Suicide rates are typically higher in males than females, while the converse is true for suicide attempts. We review this "gender paradox" in youth, and in particular, the age-dependency of these sex/gender differences and the developmental mechanisms that may explain them. Epidemiologic, genetic,neurodevelopmental and psychopathological research have identified suicidal behaviour risks arising from genetic vulnerabilities and sex/gender differences in early adverse environments, neurodevelopment, mental disorder and their complex interconnections. Further, evolving sex-/gender-defined social expectations and norms have been thought to influence suicide risk. In particular, how youth perceive and cope with threats and losses(including conforming to others' or one's own expectations of sex/gender identity) and adapt to pain(through substance use and helpseeking behaviours). Taken together, considering brain plasticity over the lifespan, these proposed antecedents to youth suicide highlight the importance of interventions that alter early environment(s)(e.g., childhood maltreatment) and/or one's ability to adapt to them. Further, such interventions may have more enduring protective effects, for the individual and for future generations, if implemented in youth.

关键词： Suicide Attempted suicide Sex Gender child Adolescent Review

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