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World Journal of Nuclear Science and Technology 2025年第1期15卷 17-29页

作者： Samuel Mofolorunsho Oyeyemi Olumide Olaife Akerele david Olakanmi Olaniyi Francis Adole Agada Sherif Olaniyi Kelani Akinkunmi Emmanuel Ladapo Ahmed Mohammed Shiyanbade Bamidele Musbau Adeniran Latifat Ronke Owoade National Institute of Radiation Protection and Research University of Ibadan Ibadan Oyo State Nigeria

Radiation doses to patients in diagnostics and interventional radiology need to be optimized to comply with the principles of radiation protection in medical practice. This involves using specific detectors with respective diagnostic beams to carry out quality control/quality assurance tests needed to optimize patient doses in the hospital. Semiconductor detectors are used in dosimetry to verify the equipment performance and dose to patients. This work aims to assess the performance, energy dependence, and response of five commercially available semiconductor detectors in RQR, RQR-M, RQA, and RQT at Secondary Standard Dosimetry for clinical applications. The diagnostic beams were generated using Exradin A4 reference ion chamber and PTW electrometer. The ambient temperature and pressure were noted for KTP correction. The detectors designed for RQR showed good performance in RQT beams and vice versa. The detectors designed for RQR-M displayed high energy dependency in other diagnostic beams. The type of diagnostic beam quality determines the response of semiconductor detectors. Therefore, a detector should be calibrated according to the beam qualities to be measured.

关键词： Semiconductor Detectors Optimization of Protection Calibration Patient Dose Diagnostic Radiology

Seasonal Fruit Quality Profile of Three Orange Varieties in Teso Subregion—Eastern Uganda

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Agricultural Sciences 2025年第1期16卷 146-160页

作者： Samuel Edgar Tinyiro Moses Matovu Norah Akaba david Bamwirire Julian Achieng Yusuf Mukasa Onesmus Semalulu Angella Kisakye Doreen Nampamya Patricia Driciru Taeson Park Cho Ilho John Adriko National Agricultural Research Organisation-National Agricultural Research Laboratories Kampala Uganda National Agricultural Research Organisation-National Livestock Resources Research Institute Kampala Uganda Korea Partnership for Innovation of Agriculture (KOPIA)-Uganda Centre Kampala Uganda National Agricultural Research Organisation-National Forestry Resources Research Institute Kampala Uganda

Teso subregion in Eastern Uganda is a leading production hub for citrus in Uganda. However, information on fruit quality profile of the three major varieties (Hamlin, Valencia and Washington navel) grown in this region was limited and/or unreported, partly resulting in their limited use for industrial processing. The current study sought to understand the seasonal quality profile of these varieties during the wet and dry seasons for the years 2019, 2022 and 2023. The study was conducted with farmers in the districts of Kumi, Ngora, Soroti and Kalaki. Mature green oranges were periodically harvested and analysed for physical and chemical properties. The results showed that the quality of oranges varied depending on the season at harvest and the variety with significant differences (p ≤ 0.05). Mean weight per fruit was highest in wet season Washington navel (277.5 g) and lowest in dry season Hamlin (149.3 g). Similarly, fruit size varied in the wet season where Washington navel (81.2 mm) had the biggest fruits while dry season Hamlin were smallest (66.6 mm). Dry season Washington navel had had the thickest peel (7.9 mm). Valencia from the wet season had the highest juice content (36.9%) compared to Washington navel (26.5%) from the dry season with the lowest. Titratable acidity was higher in the dry season Valencia (0.9%) compared to the wet season Washington navel and Hamlin (0.3%). Similarly, Total soluble solids (TSS) was higher in the dry season (Washington navel, 10.1 ˚Brix) in contrast to the wet season (Hamlin and Valencia, 7.7 ˚Brix). Valencia had the lowest pH (3.1) however, pH did not vary significantly between season for each variety except for Hamlin. Vitamin C content was higher during the dry season led by Valencia (57.6 mg/100g) and Hamlin (57.4 mg/100g). Sugar to acid ratio was highest during the wet season (Washington navel, 41.5) and lowest in the dry season (Valencia, 17.1). Overall, dry season fruits and more especially Valencia showed versatility

关键词： Citrus Quality Kyoga Plains Valencia Hamlin Washington Navel Physical Chemical

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： david A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big' five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

Natural products and drug discovery

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National Science Review 2022年第11期9卷 37-57页

作者： david J.Newman NIH Special Volunteer

This review covers the recent history of a series of very important natural products and their derivatives that are currently in use or under evaluation in the areas of anti-infectives, important cancer treatments that include antibody drug conjugates, followed by a discussion of type 2 diabetes(T2DM) drugs and angiotensin converting enzyme inhibitors. The current structures of the agents are shown, though in the case of some peptides used in T2DM drugs the standard single leTher abbreviation for an amino acid is used.

关键词： artemisinin glycopeptides anthracyclines dolastatin diabetes 2 ACE inhibitors

Variable retention harvesting in Victoria’s Mountain Ash (Eucalyptus regnans) forests (southeastern Australia)

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Ecological Processes 2019年第1期8卷 12-20页

作者： david Lindenmayer david Blair Lachlan McBurney Fenner School of Environment and Society The Australian National UniversityCanberra ACT2601Australia

Variable retention harvesting is a silvicultural system that focuses on retaining key elements of stand structure at the time of logging and is increasingly being used *** describe the design and establishment of a variable retention harvesting experiment established in the Mountain Ash(Eucalyptus regnans)forests of the Central Highlands of Victoria,south-eastern *** experiment was instigated in 2003,and the work to date has shown that it has environmental benefits for certain groups of small mammals,birds,and vascular *** experiment has been integrated with an ongoing long-term monitoring program as well as other experiments such as those in post-fire salvage-logged ***,the results of various studies suggest that the potential value of variable retention harvesting extends beyond green-tree logging to post-fire salvage logging *** outline some of the challenges in,and new perspectives derived from,implementing and maintaining our *** included difficulties protecting islands from high-intensity post-harvest regeneration burns and threat of declining funding undermining ongoing project viability.A critically important perspective concerns the ecological and economic context in which variable retention harvesting is *** the particular case of Mountain Ash forests,assessments using formal IUCN criteria classify the ecosystem as being Critically Endangered under the Red Listed Ecosystem *** a result,Mountain Ash forests are at a high risk of ecosystem *** logging will increase that risk,making the basis for continued harvesting *** addition,economic analyses suggest that the value of natural assets,like water production,far outweigh the value of the wood products harvested from the Mountain Ash ecosystem,again leading to questions about the viability of ongoing *** therefore conclude that whilst variable retention harvesting has the potential to contrib

关键词： Alternative silvicultural systems Clear-cutting Biological legacies Forest biodiversity Forest economics,Retention islands

Use of tree species by three species of Magicicada(Hemiptera:Cicadidae)in an Appalachian forest

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Journal of Forestry Research 2023年第6期34卷 2051-2063页

作者： Cindy Perkovich david Ward Department of Biology and Toxicology Ashland UniversityAshlandOH 44805USA Department of Biological Sciences Kent State UniversityKentOH 44242USA

Periodical cicadas(Magicicada spp.)are endemic to deciduous forests in the eastern United *** successional forests,they must partition resources such as host trees to *** measured tree size,emergence holes,oviposition scar bundles,and chorusing center abundances of Magicicada species on 12 common tree species in a deciduous forest to understand host-tree *** predicted that the abundance of periodical cicadas and use of specific host-tree species would change depending on the Magicicada species and tree life *** considered the size of the tree(diameter at breast height)as a covariate to control for tree size and collected eggs for a greenhouse experiment to assess whether nymphs prefer to feed on Quercus rubra or Acer *** emergence holes were found below Quercus species than any other tree *** abundance of periodical cicadas on host trees used for chorusing centers varied depending on the Magicicada species,but were most abundant on Quercus *** scar bundles were also more frequent on *** nymphs were found on Quercus than Acer in the nymph preference *** periodical cicadas used Quercus hosts more than other tree species,their abundances on different host tree sizes and species differed *** cicada species may use specific host species and life stages as a way to partition resources and minimize competition among the Magicicada species during emergence years.

关键词： Ecological succession Habitat partitioning Periodical cicadas Successional forests

Theoretical and Experimental Investigation of Driver Noncooperative-Game Steering Control Behavior

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IEEE/CAA Journal of Automatica Sinica 2021年第1期8卷 189-205页

作者： Xiaoxiang Na david Cole the Department of Engineering University of CambridgeCambridge CB21PZUK

This paper investigates two noncooperative-game strategies which may be used to represent a human driver's steering control behavior in response to vehicle automated steering *** first strategy,namely the Nash strategy is derived based on the assumption that a Nash equilibrium is reached in a noncooperative game of vehicle path-following control involving a driver and a vehicle automated steering *** second one,namely the Stackelberg strategy is derived based on the assumption that a Stackelberg equilibrium is reached in a similar context.A simulation study is performed to study the differences between the two proposed noncooperativegame *** experiment using a fixed-base driving simulator is carried out to measure six test drivers'steering behavior in response to vehicle automated steering *** Nash strategy is then fitted to measured driver steering wheel angles following a model identification *** weight parameters involved in the Nash strategy are *** is found that the proposed Nash strategy with the identified control weights is capable of representing the trend of measured driver steering behavior and vehicle lateral *** is also found that the proposed Nash strategy is superior to the classic driver steering control strategy which has widely been used for modeling driver steering control over the past.A discussion on improving automated steering control using the gained knowledge of driver noncooperative-game steering control behavior was made.

关键词： Driver experiment model identification noncooperative game steering control strategy vehicle

A methodological framework for improving air quality monitoring network *** to environment management

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Journal of Environmental Sciences 2021年第4期33卷 138-147页

作者： david Galán-Madruga Department of Atmospheric Pollution National Center for Environment HealthHealth Institute Carlos IIICtra.Majadahonda a Pozuelo km 2228220 MadridSpain

This work aims to provide a methodology framework which allows to improve the performance and efficiency of an air quality monitoring network(AQMN).It requires to be constituted by a minimum and reliable number of measurement ***,the AQMN efficiency should be assessed over time,as a consequence of the possible emergence of new emission sources of air pollutants,which could lead to variations on their spatial distribution within the target ***_(10)particles data monitored by the Community of Madrid's(Spain)AQMN between 2008 and 2017 were used to develop a methodology to optimize the AQMN *** annual spatial distribution of average PM_(10)levels over the studied period monitored by all current stations vs those more representative was provided by a geographic information system(GIS),and the percentage of similarity between both postulates was quantified using simple linear regression(>95%).As one innovative tool of this study,the practical application of the proposed methodology was validated using PM_(10)particles data measured by AQMN during 2007 and 2018,reaching a similitude degree higher than 95%.The influence of temporal variation on the proposed methodological framework was around 20%.The proposed methodology sets criteria for identifying non-redundant stations within AQMN,it is also able to appropriately assess the representativeness of fixed monitoring sites within an AQMN and it complements the guidelines set by European legislation on air pollutants monitoring at fixed stations,which could help to tackle efforts to improve the air quality management.

关键词： Air quality Ambient air monitoring network PM_(10)particles Redundant stations Optimization Environment management

On CAP Representations for Even Orthogonal Groups I:A Correspondence of Unramified Representations

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Chinese Annals of Mathematics,Series B 2015年第4期36卷 485-522页

作者： david GINZBURG Dihua JIANG david SOUDRY School of Mathematical Sciences Sackler Faculty of Exact Sciences Tel-Aviv University School of Mathematics University of Minnesota

The authors prove the local unramified correspondence for a new type of construction of CAP representations of even orthogonal groups by a generalized automorphic descent method. This method is expected to work for al... 详细信息

关键词： Automorphic representations Fourier coefficients Satake parametertransfer

The role of the general practitioner in men's health

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Asian Journal of Andrology 2020年第3期22卷 229-232页

作者： Janine david Porthcawl Medical Centre Porthcawl S Wales CF36 5DJ UK

The general practitioner(GP)is pivotally placed as an access point to provide holistic healthcare for *** are the gateway to men's *** is the GP who has the power to impact on the present health and ameliorate the future health of *** active health promotion and targeted advice and investigation,the healthcare shy man has the potential to look forward to a healthier,more fulfilled,and active life.

关键词： gateway promotion placed