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Correcting for spatially dependent intrinsic efficiency on a germanium double-sided strip detector to improve nuclear forensics response

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Radiation Detection Technology and methods 2022年第1期6卷 78-87页

作者： Timothy Jacomb-Hood James fast Craig Department of Nuclear Engineering Texas A&M UniversityCollege StationTXUSA Pacific Northwest National Laboratory RichlandWAUSA

Purpose The Germanium Gamma-ray Imager(GeGI)is a planar high-purity germanium(HPGe)imaging detector developed by PHDS Co for far-field *** research investigates the detector’s ability for measuring heterogeneous sources in the near field,placed directly on the detector’s faceplate,to perform isotopic mapping for nuclear forensic *** The intrinsic efficiency is strongly dependent on where the photons interact within the *** efficiency varies by up to 20%within the sensitive volume of the *** efficiency was mapped using eight different photons from 123 to 1274 keV emitted from a collimated 154Eu *** were measured at 108 locations to interpolate the efficiency at any point on the detector’s *** The position and energy dependence are uncorrelated,and thus,the absolute efficiency at any position and for any gamma-ray energy can be calculated by the convolution of the spatial and energy *** The results on this research show that detection efficiency for a planar two-sided strip HPGe is spatially dependent and shows typical energy *** spatial dependence,which does not have any additional energy dependence,can be corrected.A 154Eu source was used in this research and was able to spatially calibrate for photon energies ranging from 100 to 1300 *** method is applicable for sources with higher gamma *** advantages of the method demonstrated that after initial in-laboratory calibration,a single measurement in the field can be used to efficiently calibrate the HPGe as a function of photon interaction on the crystal.

关键词： Nuclear forensics Radiation detection Gamma-ray imaging

modeling regional landslide susceptibility using dynamic soil moisture profiles

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Journal of mountain Science 2018年第8期15卷 1807-1824页

作者： RAY Ram L JACOBS Jennifer m douglas Ellen m Cooperative Agricultural Research Center College of Agriculture and Human Sciences Prairie View A&M University Department of Civil Engineering University of New Hampshire Environmental Earth and Ocean Sciences Department University of Massachusetts Boston

A landslide susceptibility mapping study was performed using dynamic hillslope hydrology. The modified infinite slope stability model that directly includes vadose zone soil moisture(Sm) was applied at Cleveland Corral, California, US and Krishnabhir, Dhading, Nepal. The variable infiltration capacity(VIC-3L) model simulated vadose zone soil moisture and the wetness index hydrologic model simulated groundwater(GW). The GW model predictions had a 75% NASH-Sutcliffe efficiency when compared to California's in-situ GW measurements. The model performed best during the wet season. Using predicted GW and VIC-3L vadose zone Sm, the developed landslide susceptibility maps showed very good agreement with mapped landslides at each study region. Previous quasi-dynamic model predictions of Nepal's hazardous areas during extreme rainfall events were enhanced to improve the spatial characterization and provide the timing of hazardous conditions.

关键词： Landslide susceptibility Vadose zone Soil moisture Infiltration eapacity VIC-3L Groundwater

The impact of scavenging:perspective from casework in forensic anthropology

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Forensic Sciences Research 2020年第1期5卷 32-37页

作者： douglas H.Ubelaker Cassandra m.DeGaglia Department of Anthropology National Museum of Natural HistorySmithsonian InstitutionWashingtonDCUSA

Forensic anthropology casework frequently encounters evidence of animal scavenging asso-ciated with fragmentation and loss of skeletal *** research demonstrates that patterns of destruction in bone can suggest the size and type of animal *** study analyzes 107 cases reported on by the first author at the Smithsonian Institution to investigate patterns of scavenging in forensic anthropology *** investigation reveals that the extent of scavenger impact varies across the body,but primarily is concen-trated in the central body *** extensive animal scavenging can limit analysis,some evidence of foul play can be preserved.

关键词： Forensic sciences forensic anthropology scaveng-ing casework

Time to feed： How diet, competition, and experience may influence feeding behaviour and cannibalism in wood frog tadpoles Lithobates sylvaticus

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Current Zoology 2014年第5期60卷 571-580页

作者： Dale m. JEFFERSON Keith A. HOBSON douglas P. CHIVERS Department of Biology University of Saskatchewan 112 Science PI. Saskatoon SK Canada S7N 5E2 Environment Canada 11 Innovation Blvd. Saskatoon SK Canada S7N 3H5 Keith.Hobson@ec.gc.ca Department of Biology University of Saskatchewan 112 Science PI. Saskatoon SK Canada S7N 5E2 Doug.Chivers@usask.ca

Wood frog Lithobates sylvaticus tadpoles develop in temporary wetlands where high population densities can force tadpoles into aggregations that intensify competition and can lead to cannibalism. However, chemical alarm cues released from injured conspecifics could also dissuade cannibalism. The purpose of this study was to test mechanisms that may influence can- nibalistic behaviour. We tested whether the tendency of tadpoles to consume conspecifics would increase with the presence of competition and/or cues of profitable diets. Tadpoles placed in 1L experimental containers were tested for feeding initiation times of multiple diets, including conspecific tissues and conspecific tissues combined with chemical cues from the alternative diets （brine shrimp and comrneal）. Tadpoles were tested in the presence and absence of a competitor, and at multiple times over the course of the study. Tadpoles exhibited an altered response to diets over time; however the presence of a competitor reduced re- sponse times to all diets including conspecific tissues. Similarly, the presence of specific diets also reduced the response time of tadpoles to conspecific tissues. These results suggest competition among feeding tadpoles could result in aggressive behaviour leading to indiscriminate predation and cannibalism [Current Zoology 60 （5）： 571-580, 2014 ].

关键词： Cannibal Chemical cues Competition Diet Tadpole Wood frog

materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

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Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： Janet G douglas Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur m. Sackler Gallery at the Smithsonian Institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

Decision making for managing Community Flood Risks:Perspectives of United States Floodplain managers

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International Journal of Disaster Risk Science 2021年第5期12卷 649-660页

作者： Jenna Tyler Abdul-Akeem Sadiq douglas S.Noonan Rebecca m.Entress School of Public Administration University of Central FloridaOrlandoFL 32801USA O'Neill School of Public and Environmental Affairs Indiana University–Purdue University IndianapolisIN 46202USA

To reduce flood losses,floodplain managers make decisions on how to effectively manage their community’s flood *** there is a growing body of research that examines how individuals and households make decisions to manage their flood risks,far less attention has been directed at understanding the decision-making processes for flood management at the community *** study aimed to narrow this research gap by examining floodplain managers’perceptions of the quality of their community’s flood management decision-making *** gathered from interviews with 200 floodplain managers in the United States indicate that most floodplain managers perceive their community’s flood management decision-making processes to be *** results also indicate that communities participating in the Federal Emergency management Agency’s Community Rating System,as well as communities with a higher level of concern for flooding and a lower poverty rate,are significantly more likely to report better flood management decision-making processes.

关键词： Community flood risk management Decision making Floodplain managers United States

Characterising populations living close to intensive farming and composting facilities in England

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Frontiers of Environmental Science & Engineering 2021年第3期15卷 97-109页

作者： Philippa douglas Daniela Fecht Deborah Jarvis National Heart and Lung Institute MRC Centre for Environment and HealthImperial College LondonLondonSW36LZUK Centre for Radiation Chemical and Environmental HazardsPublic Health EnglandHarwell CampusDidcotOxfordshireOX 11 ORQUK UK Small Area Health Statistics Unit MRC Centre for Environment and HealthSchool of Public HealthImperial College LondonLondonW2 IPGUK

Bioaerosol exposure has been linked to adverse respiratory *** farming and composting facilities are important anthropogenic sources of *** aimed to characterise populations living close to intensive farming and composting *** also infer whether the public are becoming more concerned about anthropogenic bioaerosol emissions,using reports of air pollution related incidents attributed to *** mapped the location of 1,257 intensive farming and 310 composting facilities in England in relation to the resident population and its characteristics(sex and age),area characteristics(deprivation proxy and rural/urban classification)and school locations stratified by pre-defined distance bands from these bioaerosol *** also calculated the average number of air pollution related incidents per year per *** found that more than 16%of the population and 15%of schools are located within 4,828 m of an intensive farming facility or 4,000 m of a composting facility;few people(0.01%)live very close to these sites and tend to be older *** to composting facilities,populations are more likely to be urban and more *** number of incidents were attributed to a small proportion of facilities;population characteristics around these facilities were *** indicate that populations living near composting facilities(particularly>250 to≤4,000 m)are mostly located in ur6an areas(80188%of the population),which supports the need for more community health studies to be *** could also be used to inform risk management strategies at facilities with higher numbers of incidents.

关键词： Composting Intensive farming Bioaerosol Population characteristics Public health

Effects of gravity,microgravity or microgravity simulation on early mouse embryogenesis:A review of the first two space embryo studies

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mechanobiology in medicine 2024年第4期2卷 7-14页

作者： douglas m.Ruden Daniel A.Rappolee s.mott center for human health and development department of obstetrics and gynecologywayne state universitydetroitmiunited states institute of environmental health sciences wayne state universitydetroitmiunited states

many simulated micro-gravity(micro-G)experiments on earth suggest that micro-G conditions are not compatible with early mammalian embryo ***,the first two“space embryo”studies have been published showing that early mouse embryo development can occur in real microgravity(real micro-G)conditions in *** the first of these studies,published in 2020,Lei and collaborators developed automated mini-incubator(AmI)devices for mouse embryos facilitating cultivation,microscopic observation,and *** these AmI apparatuses,3400 non-frozen 2-cell embryos were launched in a recoverable satellite,experiencing sustained microgravity(~0.001G)for 64 h post-orbit before fixation in space and recovery on *** a subsequent study,in 2023,Wakayama and colleagues2 devised Embryo Thawing and Culturing(ETC)devices,enabling manual thawing,cultivation,and fixation of frozen 2-cell mouse embryos by a trained astronaut aboard the International Space Station(ISS).Within the ETCs,a total of 7202-cell mouse embryos underwent thawing and cultivation for 4 days on the ISS,subject to either microgravity(n?360)and simulated-1G(n?360)*** primary findings from both space embryo experiments indicate that mouse embryos can progress through embryogenesis from the 2-cell stage to the blastocyst stage under real micro-G conditions with few ***,these studies propose the potential for mammalian reproduction under real micro-G conditions,challenging earlier simulated micro-G research suggesting otherwise.

关键词： microgravity Clinostat International space station(ISS) Embryogenesis

Hardware,Software,and Wetware Codesign Environment for Synthetic Biology

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BioDesign Research 2022年第1期2022卷 136-150页

作者： Samuel m.D.Oliveira douglas Densmore Department of Electrical and Computer Engineering Boston UniversityMA 02215USA Biological Design Center Boston UniversityMA 02215USA

Synthetic biology is the process of forward engineering living *** systems can be used to produce biobased materials,agriculture,medicine,and *** approach to designing these systems is to employ techniques from the design of embedded *** techniques include abstraction,standards,modularity,automated design,and formal semantic models of ***,these elements form the foundation of“biodesign automation,”where software,robotics,and microfluidic devices combine to create exciting biological systems of the *** paper describes a“hardware,software,wetware”codesign vision where software tools can be made to act as“genetic compilers”that transform high-level specifications into engineered“genetic circuits”(wetware).This is followed by a process where automation equipment,welldefined experimental workflows,and microfluidic devices are explicitly designed to house,execute,and test these circuits(hardware).These systems can be used as either massively parallel experimental platforms or distributed bioremediation and biosensing ***,scheduling and control algorithms(software)manage these systems’actual execution and data analysis tasks.A distinguishing feature of this approach is how all three of these aspects(hardware,software,and wetware)may be derived from the same basic specification in parallel and generated to fulfill specific cost,performance,and structural requirements.

关键词： hardware Together execution