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Calibration method to improve the accuracy of THz imaging and spectroscopy in reflection geometry

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Photonics Research 2016年第3期4卷 29-35页

作者： Shuting Fan Edward P.j.Parrott benjamin S.Y.Ung Emma Pickwell-MacPherson Department of Electric and Computer Engineering Hong Kong University of Science and Technology Department of Electronic Engineering The Chinese University of Hong Kong

We introduce a novel method to accurately extract the optical parameters in terahertz reflection imaging. Our method builds on standard self-referencing methods using the reflected signal from the bottom of the imaging window material to further compensate for time-dependent system fluctuations and position-dependent variation in the window thickness. Our proposed method not only improves the accuracy, but also simplifies the imaging procedure and reduces measurement times.

关键词： Calibration method to improve the accuracy of THz imaging and spectroscopy in reflection geometry THz

Experimental investigation of flow pattern and sediment deposition in rectangular shallow reservoirs

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International journal of Sediment Research 2010年第3期25卷 258-270页

作者： Matthieu DUFRESNE benjamin j. DEWALS Sébastien ERPICUM Pierre ARCHAMBEAU Michel PIROTTON University of Liège (ULg) ArGEnCO department MS2F sector Hydrology applied hydrodynamics and hydraulic constructions (HACH) Chemin des chevreuils 1 bat B52/3 étage +1 4000 Liège Belgium University of Liège (ULg) ArGEnCO department MS2F sector Hydrology applied hydrodynamics and hydraulic constructions (HACH) Chemin des chevreuils 1 bat B52/3 étage +1 4000 Liège Belgium.

This paper reports the experimental investigation of flow pattern, preferential regions of deposition and trap efficiency as a function of the length of rectangular shallow reservoirs. Four flow patterns were identified (from longer to shorter reservoirs): an asymmetric flow with two reattachment points, an asymmetric flow with one reattachment point, an unstable flow, and a symmetric flow without any reattachment point. Using dye visualizations, the median value and the temporal variability of the reattachment lengths were precisely measured for the asymmetric flows. For each stable flow, sediment tests with plastic particles were carried out. The regions of deposition on the bed of the reservoir were clearly a function of the flow pattern. The transition from an asymmetric flow pattern to a symmetric flow pattern was responsible for an abrupt decrease of the trap efficiency; a number of regression laws were discussed to take it into account.

关键词： Deposition Flow patterns Reservoirs Sediment Shallow water

Reply:Is the evolution of tumors Darwinian or non-Darwinian?

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National Science Review 2018年第1期5卷 17-19页

作者： Marc j Williams benjamin Werner Chris P Barnes Trevor A Graham Andrea Sottoriva Evolution and Cancer Laboratory Barts CancerInstitute Queen Marry University of London Department of Cell and Developmental Biology University College London Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX) University College London Centre for Evolution and Cancer The Institute of Cancer Research Department of Genetics Evolution and EnvironmentUniversity College London

Wu and colleagues’letter discusses the limitations of the use of a single sample per tumor to investigate neutral evolution in human *** evolution describes the situation in which there is no differential clonal selection amongst the population of cells within a cancer:all mutations thataccrue during growth are passengers and all drivers were already present in the

关键词： Reply:Is the evolution of tumors Darwinian or non-Darwinian VAF

Acute effects of rotavirus and malnutrition on intestinal barrier function in neonatal piglets

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World journal of Gastroenterology 2013年第31期19卷 5094-5102页

作者： Sheila K jacobi Adam j Moeser Anthony T Blikslager j Marc Rhoads benjamin A Corl Robert j Harrell jack Odle Laboratory of Developmental Nutrition College of Agriculture and Life Sciences North Carolina State University Raleigh NC 27695United States College of Veterinary Medicine North Carolina State University Raleigh NC 27695United States Department of Pediatrics University of Texas Health Science Center at Houston Medical School Houston TX 77030 United States Department of Dairy Science Virginia Poly-technic Institute and State University Blacksburg VA 24061United States

AIM: To investigate the effect of protein-energy malnutrition on intestinal barrier function during rotavirus enteritis in a piglet ***: Newborn piglets were allotted at day 4 of age to the following treatments:(1) full-strength formula(FSF)/noninfected;(2) FSF/rotavirus infected;(3) half-strength formula(HSF)/noninfected;or(4) HSF/rotavirus *** one day of adjustment to the feeding rates,pigs were infected with rotavirus and acute effects on growth and diarrhea were monitored for 3 d and jejunal samples were collected for Ussingchamber ***: Piglets that were malnourished or infected had lower body weights on days 2 and 3 post-infection(P junction protein,occludin,in the cell membrane and increased localization in the ***: Overall,malnutrition had no additive effects to rotavirus infection on intestinal barrier function at day 3 post-infection in a neonatal piglet model.

关键词： Rotavirus gastroenteritis Kwashiorkor Occludin Ussing chamber Villus

Pressurization, intercalation, doping, and elements: An empirical study of superconductivity near perturbation onsets

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Superconductivity 2024年第2期10卷 29-37页

作者： Shermane M.benjamin The National High Magnetic Field Laboratory 1800 E.Paul Dirac DriveTallahasseeFL 32310USA

Superconductivity is a phenomenon arising from cooperative electron ***,correlations among(1)the minimum tuning parameter required for emergence,(2)the superconducting transition temperature resulting from minimal tuning,and(3)the host’s physical/chemical properties still elude the scientific *** empirical investigations,such as those revealing ideal gas-like correlations at the onset of superconductivity in intercalated superconductors,motivate this *** investigation reports similar findings in systems(>170 compounds)exhibiting superconductivity through other perturbative means,such as single-element *** general,statistical measures,including distance correlation analyses(≠linear regression fit)of thermodynamic variables,indicate the presence of empirical relationships near the superconducting onset of systematically tuned *** relations involve unit cell volume(V),the number of valence electrons(N),and the superconducting transition temperature(T_(c)).Note:The author’s primary aim is not to validate or challenge BCS theory;it is instead to focus on leveraging methodology led by available data to enhance the exploration and development of innovative and cost-effective superconductors.

关键词： Superconductivity Ideal gas law Empirical Doping Intercalation Critical pressure Phenomenological theory Predicting T_(c)

An investigation of the formulation and nutritional composition of modern meat analogue products

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Food Science and Human Wellness 2019年第4期8卷 320-329页

作者： benjamin M.Bohrer Department of Food Science University of Guelph50 Stone Road East GuelphOntarioN1G 2W1Canada

Meat analogues,or plant-based products that simulate the properties of traditional meat products,have secured a position in the conversation of protein *** growth of the meat analogue industry is occurring in the global food marketplace in both the retail and food service *** purpose of this review was to investigate the ingredients used in the formulation of modern meat analogues,evaluate the nutrient specifications of modern meat analogue products,and then form a comparison with traditional meat *** on this investigation,it was determined–firstly,the ingredients used in the formulation of modern meat analogue products make these products fit under the classification of ultra-processed foods;and secondly,the nutrient specifications of popular meat analogue products can effectively simulate the nutrient specifications of the meat products they are attempting to ***,based on these findings,modern meat analogue products can offer roughly the same composition of nutrients as traditional meat products,albeit with many different ingredients and a high level of further processing.

关键词： Plant-based meat Simulated meat Meat alternatives Processed foods Protein foods

Vaccination Uncertainties and COVID-19 Prospects in 2021

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China CDC weekly 2021年第7期3卷 150-152页

作者： Peng Wu benjamin j.Cowling Gabriel M.Leung WHO Collaborating Centre for Infectious Disease Epidemiology and Control School of Public HealthLKS Faculty of MedicineThe University of Hong KongHong KongChina Laboratory of Data Discovery for Health Hong Kong Science and Technology ParkHong KongChina

As we pass the first anniversary of the World Health Organization’s(WHO)declaration of a Public Health Emergency of International Concern(1),we look back at the impact of coronavirus disease 2019(COVID-19)in 2020 and... 详细信息

关键词： COV anniversary impact

Evaluation of Reynolds-averaged Navier-Stokes turbulence models in open channel flow over salmon redds

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journal of Hydrodynamics 2024年第4期36卷 741-756页

作者： Bishal Bhattarai Brandon Hilliard Daniele Tonina William j.Reeder Ralph Budwig benjamin T.Martin Tao Xing Department of Mechanical Engineering University of IdahoMoscowUSA Center for Ecohydraulics Research University of IdahoBoiseUSA Institute for Biodiversity and Ecosystem Dynamics University of AmsterdamAmsterdamThe Netherlands Hamm School of Engineering University of MaryBismarckUSA

This study evaluates computational fluid dynamics(CFD)turbulence closures for Reynolds-averaged Navier-Stokes(RANS)equations against experimental data to model complex open channel flows,like those occurring over dune-shaped salmon spawning nests called"redds".Open channel flow complexity,characterized by near-bed turbulence,adverse pressure,and free surfaces,requires suitable turbulence closure capable of capturing the flow structure between streambed and water *** evaluated three RANS models:Standard k-,shear-stress transport(SST)k-@and realizable k-,along with four wall treatments for the realizable k-:Standard,and scalable wall functions,enhanced wall treatment,and an unconventional closure combining standard wall function with near-wall mesh resolving the viscous *** all models generally capturing the bulk flow characteristics,considerable discrepancies were evident in their ability to predict specific flow features,such as flow *** realizable k-model,with standard wall function and mesh resolving viscous sublayer,outperformed other closures in predicting near-wall flow separations,velocity fields,and free surface *** realizable k-model with a log-layer resolved mesh predicted the free surface elevation equally well but lacked precision for near-wall *** SST k-@model outperformed in predicting turbulent kinetic energy and provided better predictions of the near-boundary velocity distributions than realizable k-closure with any of the conventional wall treatments but overestimated the separation vortex *** standard k-o model also overestimated near-wall *** study highlights the variability in accuracy among turbulence models,underlining the need for careful model selection based on specific prediction regions.

关键词： Salmon redd numerical simulation turbulence models volume of fluid(VOF)

Analysis of PFAAs in American alligators part 2： Potential dietary exposure of South Carolina hunters from recreationally harvested alligator meat

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journal of Environmental Sciences 2017年第11期29卷 31-38页

作者： jessica j.Tipton Louis j.Guillette jr Susan Lovelace benjamin B.Parrott Thomas R.Rainwater jessica L.Reiner College of Charleston Charleston SC 29724 USA Medical University of South Carolina Department of Obstetrics and Gynecology Charleston SC 29425 USA University of Georgia Odum School of Ecology Savannah River Ecology Laboratory Jackson SC 29831 USA Torn Yawkey Wildlife Center & Belle W. Baruch Institute of Coastal Ecology and Forest Science Clemson University P.O. Box 59(5 Georgetown SC 29442 USA National Institute of Standards and Technology Chemical Sciences Division Hollings Marine Laboratory Charleston SC 29412 USA

Exposure to perfluorinated alkyl acids（PFAAs） has been linked to many harmful health effects including reproductive disorders, developmental delays, and altered liver and kidney function. Most human exposure to environmental contaminants, including PFAAs,occurs through consumption of contaminated food or drinking water. This study uses PFAA data from meat samples collected from recreationally harvested American alligators（Alligator mississippiensis） in South Carolina to assess potential dietary exposure of hunters and their families to PFAAs. Consumption patterns were investigated using intercept surveys of 23 hunters at a wild game meat processor. An exposure scenario using the average consumption frequency, portion size, and median perfluorooctane sulfonic acid（PFOS） concentration in alligator meat from all hunt units found the daily dietary exposure to be 2.11 ng/kg body weight per day for an adult human. Dietary PFOS exposure scenarios based on location of harvest suggested the highest daily exposure occurs with alligator meat from the Middle Coastal hunt unit in South Carolina. Although no samples were found to exceed the recommended threshold for no consumption of PFOS found in Minnesota state guidelines, exposure to a mixture of PFAAs found in alligator meat and site-specific exposures based on harvest location should be considered in determining an appropriate guideline for vulnerable populations potentially exposed to PFAAs through consumption of wild alligator meat.

关键词： Public hunt American alligator Dietary exposure PFOS Consumption advisory Contaminant consumption