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Jia SB, Shamsabadi R. Secondary cancer risk assessments following the proton therapy of lung cancer as the functions of field characteristics and patient age. Int J Radiat Biol 2024; 100:183-189. [PMID: 37747407 DOI: 10.1080/09553002.2023.2263546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 09/19/2023] [Indexed: 09/26/2023]
Abstract
INTRODUCTION Radiation-induced secondary cancers relevant to proton therapy are still a main concern among cancer survivors. This study aims to determine the effects of age at exposure and treatment field size on radiation-induced secondary tumors following the proton therapy of lung cancer within out of field organs through the Monte Carlo (MC) simulation approach. MATERIAL AND METHODS A full MC model of ICRP-110 male phantom was simulated to calculate the absorbed dose corresponding to secondary radiations within distant organs from the tumor volume. Then, the risks of secondary malignancies were estimated by employing the recommended risk model by the Committee of Biological Effects of Ionizing Radiation (BEIR) for different treatment field sizes and various patient ages at exposure. RESULTS The results revealed that by increasing the patient age from 25 to 45 years, lifetime attributable risk (LAR) values were decreased. Maximum and minimum mortality rates were obtained for the liver and thyroid at the fixed age of 25 years, respectively. Calculated risk values for most near organs to the tumor were higher than those for distant organs. Changing the aperture size from 5 × 5 cm2 to 8 × 10 cm2 resulted in LAR increments with maximum variations of 12.5% for the stomach and a rough variation of 1.12 times in LAR for all exposure ages. CONCLUSION Our work on whole-body phantom addresses the impact of age at exposure and aperture size on LAR during the proton therapy of lung cancer. To minimize secondary cancer risks relevant to proton therapy of lung cancer, extra attention should be considered.
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Affiliation(s)
| | - Reza Shamsabadi
- Physics Department, Hakim Sabzevari University, Sabzevar, Iran
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2
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Khan S, Fahrig L, Martin AE. Support for an area-heterogeneity tradeoff for biodiversity in croplands. Ecol Appl 2023; 33:e2820. [PMID: 36792925 DOI: 10.1002/eap.2820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 11/24/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Rapid expansion of the human population poses a challenge for wildlife conservation in agricultural landscapes. One proposal for addressing this challenge is to increase biodiversity in such landscapes by increasing crop diversity. However, studies report both positive and negative effects of crop diversity on biodiversity. One possible explanation, derived from the "area-heterogeneity tradeoff hypothesis," is that the effect of crop diversity on biodiversity depends on a tradeoff between increasing the number of crop types in a landscape and decreasing the amount of each single crop type. This should cause positive effects of increasing crop diversity at low to intermediate crop diversity and negative effects at intermediate to high crop diversity. We also propose two factors that could change the point at which the effect of increasing crop diversity shifts from positive to negative. First, we predicted that this shift would occur at a lower crop diversity when the surrounding landscape contains less semi-natural habitat and at a higher crop diversity when the landscape contains more semi-natural habitat. This should increase the likelihood of detecting negative effects of crop diversity when semi-natural cover is low and positive effects when it is high. Second, we predicted that the shift from a positive to negative effect would occur at a lower crop diversity when it is measured locally than when it is measured at greater distances from the site, making detection of negative crop diversity effects more likely when measurements are at local extents. We tested these predictions using data on the biodiversity of herbaceous plants, butterflies, syrphid flies, woody plants, bees, carabid beetles, spiders, and birds at 221 crop field edges in Eastern Ontario, Canada. We found support for an area-crop diversity tradeoff. Semi-natural cover and measurement extent influenced the biodiversity-crop diversity relationship, with positive effects when semi-natural cover was high and negative effects when semi-natural cover was low and when crop diversity was measured at local extents. The results suggest that policies/guidelines designed to increase crop diversity will not benefit biodiversity in the landscapes where conservation action is most urgently needed, that is, in landscapes with high agricultural use and low semi-natural cover.
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Affiliation(s)
- Sara Khan
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
| | - Lenore Fahrig
- Geomatics and Landscape Ecology Laboratory, Carleton University, Ottawa, Ontario, Canada
| | - Amanda E Martin
- Department of Biology, Carleton University, Ottawa, Ontario, Canada
- National Wildlife Research Centre, Environment and Climate Change Canada, Ottawa, Ontario, Canada
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3
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Jo A, Kim E. Radiation dose evaluation to organs in neonatal patients by field size during potable X-ray examination in incubators: A Monte Carlo simulation study. J Xray Sci Technol 2023; 31:1115-1124. [PMID: 37545249 DOI: 10.3233/xst-230080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
BACKGROUND Neonatal patients located in incubators are exposed to as many as 159 radiographs until discharge. To reduce the dose exposed to the patient, factors that may cause unnecessary exposure to the patient were judged. When conducting portable X-rays of neonatal patients located in an incubator, it is not easy to determine the exact field size because collimation light is exposed on the acrylic plate, an incubator canopy, and the resulting shadow is reflected on the patient's body. OBJECTIVE This study aims to measure the organ dose exposed to the patient according to the field size when a portable radiograph is given to a neonatal patient in a neonatal intensive care unit (NICU) incubator. METHODS To identify the absorbed organ dose depending on the radiation field size during portable X-ray examination of neonatal patient, a Monte Carlo N-Particle (MCNP) simulation, a SpeckCalc program, and a neonatal phantom from the ICRP 89 are applied for the calculation. According to the minimal field size (MinFS) standards of the European Commission (EC), the smaller field size is intended to measure tightly from the top of the lung apices to the bottom of the genitals; a larger field size is also calculated by adding 6 cm in width and length. RESULTS Compared to the hospital C condition from the previous study, the larger and smaller field sizes are decreased by an average of 45% and 67%, respectively. Study results also show a 42% reduction in smaller field size compared to the larger field size. CONCLUSION When taking chest and abdomen radiographic images of neonatal patients in incubators, appropriate field sizes are required to prevent inappropriate dose absorption for non-thoracic organs.
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Affiliation(s)
- Ajin Jo
- Health Science Research Center, Korea University, Seoul, Republic of Korea
| | - Eunhye Kim
- Health Science Research Center, Korea University, Seoul, Republic of Korea
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4
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Rosenheim JA, Cluff E, Lippey MK, Cass BN, Paredes D, Parsa S, Karp DS, Chaplin-Kramer R. Increasing crop field size does not consistently exacerbate insect pest problems. Proc Natl Acad Sci U S A 2022; 119:e2208813119. [PMID: 36067287 DOI: 10.1073/pnas.2208813119] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Increasing diversity on farms can enhance many key ecosystem services to and from agriculture, and natural control of arthropod pests is often presumed to be among them. The expectation that increasing the size of monocultural crop plantings exacerbates the impact of pests is common throughout the agroecological literature. However, the theoretical basis for this expectation is uncertain; mechanistic mathematical models suggest instead that increasing field size can have positive, negative, neutral, or even nonlinear effects on arthropod pest densities. Here, we report a broad survey of crop field-size effects: across 14 pest species, 5 crops, and 20,000 field years of observations, we quantify the impact of field size on pest densities, pesticide applications, and crop yield. We find no evidence that larger fields cause consistently worse pest impacts. The most common outcome (9 of 14 species) was for pest severity to be independent of field size; larger fields resulted in less severe pest problems for four species, and only one species exhibited the expected trend of larger fields worsening pest severity. Importantly, pest responses to field size strongly correlated with their responses to the fraction of the surrounding landscape planted to the focal crop, suggesting that shared ecological processes produce parallel responses to crop simplification across spatial scales. We conclude that the idea that larger field sizes consistently disrupt natural pest control services is without foundation in either the theoretical or empirical record.
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5
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Deng Y, Wang Q, Huang Z. Technical Note: Field size analysis of patient-specific quality assurance in scanned carbon ion radiotherapy. Med Phys 2021; 48:6627-6633. [PMID: 34648191 DOI: 10.1002/mp.15279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 09/09/2021] [Accepted: 09/23/2021] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To evaluate the dose difference between measurement and double Gaussian beam model prediction according to the field size and correct the measurements in patient-specific quality assurance (QA). METHODS The field size dependence of the dose was evaluated with volumes of 20 × 20 × 80 mm3 , 40 × 40 × 80 mm3 , 60 × 60 × 80 mm3 , and 80 × 80 × 80 mm3 of 1 Gy uniform dose at three depths. Additional two 80 × 80 × 80 mm3 volumes of nonuniform fields were created: one high-dose field was given 1 Gy at the central 40 × 40 mm2 and 0.5 Gy in its surrounding, and the other low-dose field was given 0.5 Gy in the middle and 1 Gy at the periphery. The dose in the center of the spread-out Bragg peak (SOBP) was measured in a water phantom and compared with the treatment planning system (TPS) predication. A field factor based on the two-dimensional (2D) dose distribution was proposed to estimate the field size. The field factor was first evaluated against the dose difference in the square fields, and then used to analyze and correct the patient-specific QA results. RESULTS TPS overestimated dose for fields smaller than 80 × 80 mm2 . A practically positive correlation was observed between the measured dose and the field factor. In the patient-specific QA, measured doses were lower than the TPS predication as they were calculated a relatively small field factor. The corrected dose differences were no longer field factor dependent. CONCLUSIONS Using the proposed field factor, we have shown that all the measurements with a large dose deviation were due to the small-sized field. It is clinically relevant to take into consideration the field size in the QA analysis as long as the double Gaussian beam model being used for the dose calculation. Correction to the measurement can be made based on the field factor.
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Affiliation(s)
- Yu Deng
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China.,Shanghai Key Laboratory of Radiation Oncology (20dz2261000).,Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, China
| | - Qianxia Wang
- Department of Physics and Astronomy, Rice University, Houston, Texas, USA.,Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Zhijie Huang
- Department of Medical Physics, Shanghai Proton and Heavy Ion Center, Shanghai, China.,Shanghai Key Laboratory of Radiation Oncology (20dz2261000).,Shanghai Engineering Research Center of Proton and Heavy Ion Radiation Therapy, Shanghai, China
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6
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Tscharntke T, Grass I, Wanger TC, Westphal C, Batáry P. Beyond organic farming - harnessing biodiversity-friendly landscapes. Trends Ecol Evol 2021; 36:919-930. [PMID: 34362590 DOI: 10.1016/j.tree.2021.06.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/09/2021] [Accepted: 06/16/2021] [Indexed: 11/27/2022]
Abstract
We challenge the widespread appraisal that organic farming is the fundamental alternative to conventional farming for harnessing biodiversity in agricultural landscapes. Certification of organic production is largely restricted to banning synthetic agrochemicals, resulting in limited benefits for biodiversity but high yield losses despite ongoing intensification and specialisation. In contrast, successful agricultural measures to enhance biodiversity include diversifying cropland and reducing field size, which can multiply biodiversity while sustaining high yields in both conventional and organic systems. Achieving a landscape-level mosaic of natural habitat patches and fine-grained cropland diversification in both conventional and organic agriculture is key for promoting large-scale biodiversity. This needs to be urgently acknowledged by policy makers for an agricultural paradigm shift.
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Affiliation(s)
| | - Ingo Grass
- Ecology of Tropical Agricultural Systems, University of Hohenheim, Stuttgart, Germany
| | - Thomas C Wanger
- Sustainability, Agriculture, & Technology Laboratory, School of Engineering, Westlake University, China; Key Laboratory of Coastal Environment and Resources of Zhejiang Province, Westlake University, Hangzhou, China; GlobalAgroforestryNetwork.org, Westlake University, Hangzhou, China.
| | - Catrin Westphal
- Functional Agrobiodiversity, University of Göttingen, Göttingen, Germany
| | - Péter Batáry
- "Lendület" Landscape and Conservation Ecology, Institute of Ecology and Botany, Centre for Ecological Research, Vácrátót, Hungary
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7
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Rastegar S, Beigi J, Saeedi E, Shiri I, Qasempour Y, Rezaei M, Abdollahi H. Radiographic Image Radiomics Feature Reproducibility: A Preliminary Study on the Impact of Field Size. J Med Imaging Radiat Sci 2020; 51:128-136. [PMID: 32089514 DOI: 10.1016/j.jmir.2019.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 10/26/2019] [Accepted: 11/12/2019] [Indexed: 01/20/2023]
Abstract
RATIONALE AND OBJECTIVES Radiomics is an approach to quantifying diseases. Recently, several studies have indicated that radiomics features are vulnerable against imaging parameters. The aim of this study is to assess how radiomics features change with radiographic field sizes, positions in the field size, and mAs. MATERIALS AND METHODS A large and small wood phantom and a cotton phantom were prepared and imaged in different field sizes, mAs, and placement in the radiographic field size. A region of interest was drawn on the image features, and twenty two features were extracted. Radiomics feature reproducibility was obtained based on coefficient of variation, Bland-Altman analysis, and intraclass correlation coefficient. Features with coefficient of variation ≤ 5%, intraclass correlation coefficient ≤ 90%, and 1% ≤ U/LRL ≤30% were introduced as robust features. U/LRL is upper/lower reproducibility limits in Bland-Altman. RESULTS For all field sizes and all phantoms, features including Difference Variance, Inverse Different Moment, Fraction, Long Run Emphasis, Run Length Non Uniformity, and Short Run Emphasis were found as highly reproducible features. For change in the position of field size, Fraction was the most reproducible in all field sizes and all phantoms. On the mAs change, we found that feature, Short Run Emphasis field 15 × 15 for small wood phantom, and Correlation in all field sizes for Cotton are the most reproducible features. CONCLUSION We demonstrated that radiomics features are strongly vulnerable against radiographic field size, positions in the radiation field, mAs, and phantom materials, and reproducibility analyses should be performed before each radiomics study. Moreover, these changing parameters should be considered, and their effects should be minimized in future radiomics studies.
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Affiliation(s)
- Sajjad Rastegar
- Student Research Committee, Paramedical Faculty, Rafsanjan University of Medical Sciences, Rafsanjan, Iran; Department of Radiology Technology, Paramedical Faculty, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
| | - Jalal Beigi
- Student Research Committee, Paramedical Faculty, Rafsanjan University of Medical Sciences, Rafsanjan, Iran; Department of Radiology Technology, Paramedical Faculty, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
| | - Ehsan Saeedi
- Student Research Committee, Paramedical Faculty, Rafsanjan University of Medical Sciences, Rafsanjan, Iran; Department of Radiology Technology, Paramedical Faculty, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
| | - Isaac Shiri
- Division of Nuclear Medicine and Molecular Imaging, Department of Medical Imaging, Geneva University Hospital, Geneva 4, Switzerland
| | - Younes Qasempour
- Student Research Committee, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Mostafa Rezaei
- Student Research Committee, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | - Hamid Abdollahi
- Student Research Committee, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran; Department of Radiologic Sciences and Medical Physics, Faculty of Allied Medicine, Kerman University of Medical Sciences, Kerman, Iran.
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8
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Xie K, Sun H, Gao L, Sui J, Lin T, Ni X. A study on the correlation between radiation field size and gamma index passing rate for MatriXX. Medicine (Baltimore) 2019; 98:e16536. [PMID: 31348271 PMCID: PMC6709154 DOI: 10.1097/md.0000000000016536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
This study aimed to analyze the influence of the radiation field size on the passing rate of the treatment planning system using MatriXX if the field irradiated the circuit.Two sets of static fields which were 10 cm and 30 cm in the left-right direction (X), and was 31 cm to 40 cm in gun-target direction (Y) were designed. In these fields, the gantry was 0 and the monitor units were 200 MU. Two plans from an esophagus carcinoma patient with a planning target volume of 86.4 cm and a cervical carcinoma patient with a planning target volume (PTV) of 2094.1 cm were chosen. The passing rates of these plans were gained without and with protecting the circuit area from lead alloys. The gamma analysis was used and the standard was set to 3%/3 mm.The verification passing rate decreased from 95.0% to 69.2% when X was 10 cm while Y increased from 31 cm to 40 cm. With the protection from low melting point lead alloys, the passing rate was from 96.2% to 89.6%. The results of the second set of plans without lead alloys were similar but the passing rate decreased more sharply. The passing rates of the 2 patients were 99.5% and 57.1%. With the protection of the lead alloys, their passing rates were 99.8% and 72.1%, respectively.The results showed that with the increase of the radiation field size in the Y direction, more areas were irradiated in the circuit, and the passing rate gradually decreases and dropped sharply at a certain threshold. After putting lead alloys above the circuit, the passing rate was much better in the static field but was still less than 90% in the second patient volumetric modulated arc therapy (VMAT) because the circuit was irradiate in other directions. In daily QA, we should pay attention to these patients with long size tumor.
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Affiliation(s)
- Kai Xie
- Department of Radiation Oncology, Changzhou No. 2 People's Hospital, Nanjing Medical University
- The Center for Medical Physics of Nanjing Medical University, Changzhou, China
| | - Hongfei Sun
- Department of Radiation Oncology, Changzhou No. 2 People's Hospital, Nanjing Medical University
- The Center for Medical Physics of Nanjing Medical University, Changzhou, China
| | - Liugang Gao
- Department of Radiation Oncology, Changzhou No. 2 People's Hospital, Nanjing Medical University
- The Center for Medical Physics of Nanjing Medical University, Changzhou, China
| | - Jianfeng Sui
- Department of Radiation Oncology, Changzhou No. 2 People's Hospital, Nanjing Medical University
- The Center for Medical Physics of Nanjing Medical University, Changzhou, China
| | - Tao Lin
- Department of Radiation Oncology, Changzhou No. 2 People's Hospital, Nanjing Medical University
- The Center for Medical Physics of Nanjing Medical University, Changzhou, China
| | - Xinye Ni
- Department of Radiation Oncology, Changzhou No. 2 People's Hospital, Nanjing Medical University
- The Center for Medical Physics of Nanjing Medical University, Changzhou, China
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Hass AL, Kormann UG, Tscharntke T, Clough Y, Baillod AB, Sirami C, Fahrig L, Martin JL, Baudry J, Bertrand C, Bosch J, Brotons L, Burel F, Georges R, Giralt D, Marcos-García MÁ, Ricarte A, Siriwardena G, Batáry P. Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe. Proc Biol Sci 2019; 285:rspb.2017.2242. [PMID: 29445017 DOI: 10.1098/rspb.2017.2242] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 01/25/2018] [Indexed: 11/12/2022] Open
Abstract
Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish (Raphanus sativus), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management.
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Affiliation(s)
- Annika L Hass
- Agroecology, Department of Crop Science, University of Goettingen, Goettingen, Germany
| | - Urs G Kormann
- Agroecology, Department of Crop Science, University of Goettingen, Goettingen, Germany.,Forest Biodiversity Research Network, Oregon State University, Corvallis, USA
| | - Teja Tscharntke
- Agroecology, Department of Crop Science, University of Goettingen, Goettingen, Germany
| | - Yann Clough
- Agroecology, Department of Crop Science, University of Goettingen, Goettingen, Germany.,Centre for Environmental and Climate Research, Lund University, Lund, Sweden
| | - Aliette Bosem Baillod
- Agroecology, Department of Crop Science, University of Goettingen, Goettingen, Germany
| | - Clélia Sirami
- Centre d'Écologie Fonctionnelle et Évolutive UMR 5175, CNRS-Université de Montpellier-Université Paul Valéry Montpellier-IRD-EPHE, Montpellier Cedex 5, France.,UMR 1201 Dynafor, INRA-INP Toulouse-ENSAT, Toulouse, France
| | - Lenore Fahrig
- Geomatics and Landscape Ecology Laboratory, Carleton University, Ottawa, Ontario, Canada
| | - Jean-Louis Martin
- Centre d'Écologie Fonctionnelle et Évolutive UMR 5175, CNRS-Université de Montpellier-Université Paul Valéry Montpellier-IRD-EPHE, Montpellier Cedex 5, France
| | | | - Colette Bertrand
- UR 0980 SAD Paysage, INRA 65, Rennes Cedex, France.,UMR 6553 ECOBIO, CNRS, Rennes, France
| | | | - Lluís Brotons
- CREAF, Bellaterra, Spain.,InForest Jru (CTFC-CREAF), Solsona, Spain.,CSIC, Cerdanyola del Vallès, Spain
| | | | | | - David Giralt
- CTFC (Forest Sciences Centre of Catalonia), Solsona, Spain
| | - María Á Marcos-García
- Instituto Universitario de Investigación, CIBIO, Centro Iberoamericano de la Biodiversidad, University of Alicante, San Vicente del Raspeig, Alicante, Spain
| | - Antonio Ricarte
- Instituto Universitario de Investigación, CIBIO, Centro Iberoamericano de la Biodiversidad, University of Alicante, San Vicente del Raspeig, Alicante, Spain
| | | | - Péter Batáry
- Agroecology, Department of Crop Science, University of Goettingen, Goettingen, Germany.,GINOP Sustainable Ecosystems Group, MTA Centre for Ecological Research, Hungary
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10
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Lesiv M, Laso Bayas JC, See L, Duerauer M, Dahlia D, Durando N, Hazarika R, Kumar Sahariah P, Vakolyuk M, Blyshchyk V, Bilous A, Perez‐Hoyos A, Gengler S, Prestele R, Bilous S, Akhtar IUH, Singha K, Choudhury SB, Chetri T, Malek Ž, Bungnamei K, Saikia A, Sahariah D, Narzary W, Danylo O, Sturn T, Karner M, McCallum I, Schepaschenko D, Moltchanova E, Fraisl D, Moorthy I, Fritz S. Estimating the global distribution of field size using crowdsourcing. Glob Chang Biol 2019; 25:174-186. [PMID: 30549201 PMCID: PMC7379266 DOI: 10.1111/gcb.14492] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 09/16/2018] [Indexed: 05/07/2023]
Abstract
There is an increasing evidence that smallholder farms contribute substantially to food production globally, yet spatially explicit data on agricultural field sizes are currently lacking. Automated field size delineation using remote sensing or the estimation of average farm size at subnational level using census data are two approaches that have been used. However, both have limitations, for example, automatic field size delineation using remote sensing has not yet been implemented at a global scale while the spatial resolution is very coarse when using census data. This paper demonstrates a unique approach to quantifying and mapping agricultural field size globally using crowdsourcing. A campaign was run in June 2017, where participants were asked to visually interpret very high resolution satellite imagery from Google Maps and Bing using the Geo-Wiki application. During the campaign, participants collected field size data for 130 K unique locations around the globe. Using this sample, we have produced the most accurate global field size map to date and estimated the percentage of different field sizes, ranging from very small to very large, in agricultural areas at global, continental, and national levels. The results show that smallholder farms occupy up to 40% of agricultural areas globally, which means that, potentially, there are many more smallholder farms in comparison with the two different current global estimates of 12% and 24%. The global field size map and the crowdsourced data set are openly available and can be used for integrated assessment modeling, comparative studies of agricultural dynamics across different contexts, for training and validation of remote sensing field size delineation, and potential contributions to the Sustainable Development Goal of Ending hunger, achieve food security and improved nutrition and promote sustainable agriculture.
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Affiliation(s)
- Myroslava Lesiv
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | | | - Linda See
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Martina Duerauer
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Domian Dahlia
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | | | | | | | - Mar'yana Vakolyuk
- Department of Energy and Mass Exchange in GeosystemsState Institution Scientific Centre for Aerospace Research of the Earth Institute of Geological Science National Academy of Sciences of UkraineKyivUkraine
| | - Volodymyr Blyshchyk
- Forest ManagementNacional'nyj Universytet Bioresursiv i Pryrodokorystuvannya UkrayinyKyivUkraine
| | - Andrii Bilous
- Department of Energy and Mass Exchange in GeosystemsState Institution Scientific Centre for Aerospace Research of the Earth Institute of Geological Science National Academy of Sciences of UkraineKyivUkraine
| | - Ana Perez‐Hoyos
- European Commission Joint Research Centre Ispra SectorIspraItaly
| | - Sarah Gengler
- Environmental SciencesUniversité catholique de Louvain, Earth and Life InstituteLouvain‐la‐NeuveBelgium
| | - Reinhard Prestele
- Department of Earth Sciences, Environmental Geography GroupVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Svitlana Bilous
- Forest ManagementNacional'nyj Universytet Bioresursiv i Pryrodokorystuvannya UkrayinyKyivUkraine
| | - Ibrar ul Hassan Akhtar
- Department of MeteorologyCOMSATS UniversityIslamabadPakistan
- Pakistan Space and Upper Atmosphere Research CommissionIslamabadPakistan
| | | | | | | | - Žiga Malek
- Vrije Universiteit Amsterdam Faculteit Economische wetenschappen en BedrijfskundeAmsterdamThe Netherlands
| | | | | | | | | | - Olha Danylo
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Tobias Sturn
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Mathias Karner
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Ian McCallum
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Dmitry Schepaschenko
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
- Soil ScienceMoscow State Forest UniversityMoscowRussia
| | | | - Dilek Fraisl
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Inian Moorthy
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
| | - Steffen Fritz
- International Institute for Applied Systems Analysis, ESMLaxenburgAustria
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Chuter RW, Whitehurst P, Choudhury A, van Herk M, McWilliam A. Technical Note: Investigating the impact of field size on patient selection for the 1.5T MR-Linac. Med Phys 2017; 44:5667-5671. [PMID: 28869651 DOI: 10.1002/mp.12557] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/10/2017] [Accepted: 08/14/2017] [Indexed: 11/09/2022] Open
Abstract
PURPOSE The 1.5 T Elekta MR-Linac, due to the construction of the system will have a maximum radiation field size in the superior-inferior patient direction of 22 cm at isocentre. The field size may impact on the patient groups which can be treated on the system. This technical note aims to address the question of which treatment sites will be affected by field size limitations on the MR-Linac. METHODS Using historical data for 11 595 cases over 2 yr treated at the authors' institution, the proportion of plans that would fit the MR-Linac's field size was determined for eleven patient groups. In addition, cervix plans were analyzed to determine the length of the two Clinical Target Volumes (CTVs) and any overlap between them. RESULTS With a 1 cm margin to allow for online plan adaption, 80% of all plans would be suitable for the MR-Linac due to the field size. This percentage increases to 100% for smaller tumor volumes such as prostate and brain. However, for cervix and three dose-level head and neck plans the percentage becomes 61% and 66%, respectively. CONCLUSION The maximum radiation field size of the MR-Linac in the superior-inferior patient direction is 22 cm. With a 1 cm margin approximately 80% of all plans would be suitable for the MR-Linac with the available field size, decreasing to 61% for larger tumor volumes. For cervix patients this may motivate investigations into treating each CTV with a separate isocentre, allowing for careful control of matching fields.
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Affiliation(s)
- Robert W Chuter
- Christie Medical Physics and Engineering (CMPE), The Christie NHS Foundation Trust, Wilmslow Road, Manchester, M20 4BX, UK
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, M13 9PL, UK
| | - Philip Whitehurst
- Christie Medical Physics and Engineering (CMPE), The Christie NHS Foundation Trust, Wilmslow Road, Manchester, M20 4BX, UK
| | - Ananya Choudhury
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, M13 9PL, UK
- Clinical Oncology, The Christie NHS Foundation Trust, Wilmslow Road, Manchester, M20 4BX, UK
| | - Marcel van Herk
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, M13 9PL, UK
| | - Alan McWilliam
- Christie Medical Physics and Engineering (CMPE), The Christie NHS Foundation Trust, Wilmslow Road, Manchester, M20 4BX, UK
- Division of Cancer Sciences, Manchester Cancer Research Centre, University of Manchester, Manchester Academic Health Sciences Centre, Manchester, M13 9PL, UK
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Fritz S, See L, McCallum I, You L, Bun A, Moltchanova E, Duerauer M, Albrecht F, Schill C, Perger C, Havlik P, Mosnier A, Thornton P, Wood-Sichra U, Herrero M, Becker-Reshef I, Justice C, Hansen M, Gong P, Abdel Aziz S, Cipriani A, Cumani R, Cecchi G, Conchedda G, Ferreira S, Gomez A, Haffani M, Kayitakire F, Malanding J, Mueller R, Newby T, Nonguierma A, Olusegun A, Ortner S, Rajak DR, Rocha J, Schepaschenko D, Schepaschenko M, Terekhov A, Tiangwa A, Vancutsem C, Vintrou E, Wenbin W, van der Velde M, Dunwoody A, Kraxner F, Obersteiner M. Mapping global cropland and field size. Glob Chang Biol 2015; 21:1980-92. [PMID: 25640302 DOI: 10.1111/gcb.12838] [Citation(s) in RCA: 134] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/30/2014] [Accepted: 12/08/2014] [Indexed: 05/19/2023]
Abstract
A new 1 km global IIASA-IFPRI cropland percentage map for the baseline year 2005 has been developed which integrates a number of individual cropland maps at global to regional to national scales. The individual map products include existing global land cover maps such as GlobCover 2005 and MODIS v.5, regional maps such as AFRICOVER and national maps from mapping agencies and other organizations. The different products are ranked at the national level using crowdsourced data from Geo-Wiki to create a map that reflects the likelihood of cropland. Calibration with national and subnational crop statistics was then undertaken to distribute the cropland within each country and subnational unit. The new IIASA-IFPRI cropland product has been validated using very high-resolution satellite imagery via Geo-Wiki and has an overall accuracy of 82.4%. It has also been compared with the EarthStat cropland product and shows a lower root mean square error on an independent data set collected from Geo-Wiki. The first ever global field size map was produced at the same resolution as the IIASA-IFPRI cropland map based on interpolation of field size data collected via a Geo-Wiki crowdsourcing campaign. A validation exercise of the global field size map revealed satisfactory agreement with control data, particularly given the relatively modest size of the field size data set used to create the map. Both are critical inputs to global agricultural monitoring in the frame of GEOGLAM and will serve the global land modelling and integrated assessment community, in particular for improving land use models that require baseline cropland information. These products are freely available for downloading from the http://cropland.geo-wiki.org website.
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Affiliation(s)
- Steffen Fritz
- International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, A-2361, Laxenburg, Austria
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White EV, Roy DP. A contemporary decennial examination of changing agricultural field sizes using Landsat time series data. Geo 2015; 2:33-54. [PMID: 27669424 PMCID: PMC5020581 DOI: 10.1002/geo2.4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 01/29/2015] [Accepted: 02/17/2015] [Indexed: 06/06/2023]
Abstract
Field size distributions and their changes have not been studied over large areas as field size change datasets are not available. This study quantifies agricultural field size changes in a consistent manner using Landsat satellite data that also provide geographic context for the observed decadal scale changes. Growing season cloud-free Landsat 30 m resolution images acquired from 9 to 25 years apart were used to extract field object classifications at seven sites located by examination of a global agricultural yield map, agricultural production statistics, literature review, and analysis of the imagery in the US Landsat archive. High spatial resolution data were used to illustrate issues identifying small fields that are not reliably discernible at 30 m Landsat resolution. The predominant driver of field size change was attributed by literature review. Significant field size changes were driven by different factors, including technological advancements (Argentina and USA), government land use and agricultural policies (Malaysia, Brazil, France), and political changes (Albania and Zimbabwe). While observed local field size changes were complex, the reported results suggest that median field sizes are increasing due to technological advancements and changes to government policy, but may decrease where abrupt political changes affect the agricultural sector and where pastures are converted to arable land uses. In the limited sample considered, median field sizes increased from 45% (France) to 159% (Argentina) and decreased from 47% (Brazil) to 86% (Albania). These changes imply significant impacts on landscape spatial configuration and land use diversity with ecological and biogeochemical consequences.
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Affiliation(s)
- Emma V White
- Geospatial Sciences Center of Excellence, Wecota Hall South Dakota State University Brookings SD 57007 USA
| | - David P Roy
- Geospatial Sciences Center of Excellence, Wecota Hall South Dakota State University Brookings SD 57007 USA
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