Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

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    Reproducible molecular networking of untargeted mass spectrometry data using GNPS
    Aron, Allegra T. ; Gentry, Emily C. ; McPhail, Kerry L. ; Nothias, Louis Félix ; Nothias-Esposito, Mélissa ; Bouslimani, Amina ; Petras, Daniel ; Gauglitz, Julia M. ; Sikora, Nicole ; Vargas, Fernando ; Hooft, Justin J.J. van der; Ernst, Madeleine ; Kang, Kyo Bin ; Aceves, Christine M. ; Caraballo-Rodríguez, Andrés Mauricio ; Koester, Irina ; Weldon, Kelly C. ; Bertrand, Samuel ; Roullier, Catherine ; Sun, Kunyang ; Tehan, Richard M. ; Boya P, Cristopher A. ; Christian, Martin H. ; Gutiérrez, Marcelino ; Ulloa, Aldo Moreno ; Tejeda Mora, Javier Andres ; Mojica-Flores, Randy ; Lakey-Beitia, Johant ; Vásquez-Chaves, Victor ; Zhang, Yilue ; Calderón, Angela I. ; Tayler, Nicole ; Keyzers, Robert A. ; Tugizimana, Fidele ; Ndlovu, Nombuso ; Aksenov, Alexander A. ; Jarmusch, Alan K. ; Schmid, Robin ; Truman, Andrew W. ; Bandeira, Nuno ; Wang, Mingxun ; Dorrestein, Pieter C. - \ 2020
    Nature protocols (2020). - ISSN 1754-2189

    Global Natural Product Social Molecular Networking (GNPS) is an interactive online small molecule–focused tandem mass spectrometry (MS2) data curation and analysis infrastructure. It is intended to provide as much chemical insight as possible into an untargeted MS2 dataset and to connect this chemical insight to the user’s underlying biological questions. This can be performed within one liquid chromatography (LC)-MS2 experiment or at the repository scale. GNPS-MassIVE is a public data repository for untargeted MS2 data with sample information (metadata) and annotated MS2 spectra. These publicly accessible data can be annotated and updated with the GNPS infrastructure keeping a continuous record of all changes. This knowledge is disseminated across all public data; it is a living dataset. Molecular networking—one of the main analysis tools used within the GNPS platform—creates a structured data table that reflects the molecular diversity captured in tandem mass spectrometry experiments by computing the relationships of the MS2 spectra as spectral similarity. This protocol provides step-by-step instructions for creating reproducible, high-quality molecular networks. For training purposes, the reader is led through a 90- to 120-min procedure that starts by recalling an example public dataset and its sample information and proceeds to creating and interpreting a molecular network. Each data analysis job can be shared or cloned to disseminate the knowledge gained, thus propagating information that can lead to the discovery of molecules, metabolic pathways, and ecosystem/community interactions.

    First report of Fusarium Wilt Tropical race 4 in Cavendish Bananas Caused by Fusarium odoratissimum in Colombia
    García-Bastidas, F.A. ; Quintero-Vargas, J.C. ; Ayala-Vasquez, M. ; Schermer, T. ; Seidl, M.F. ; Santos-Paiva, M. ; Noguera, A.M. ; Aguilera-Galvez, C. ; Wittenberg, A. ; Hofstede, R. ; Sørensen, A. ; Kema, G.H.J. - \ 2020
    Plant Disease 104 (2020)3. - ISSN 0191-2917
    Survey of clenbuterol in bovine muscle and liver in Ecuador
    Espinoza, Wania ; Vargas Jentzsch, Paul ; Gualpa, Fernando ; Andrade, Paulette ; Moreno, Carla ; Vaca, Israel ; Betancourt, Rommel ; Medina, Lorena ; Enríquez, Dominique ; Guijarro, Michelle ; Garrido, Patricia ; Bravo, Juan ; Ulic, Sonia ; Montalvo García, Gemma ; Ortega, Fernando ; Stolker, Linda ; Ramos, Luis - \ 2020
    Food Additives & Contaminants Part B-Surveillance 13 (2020)2. - ISSN 1939-3210 - p. 107 - 114.
    Clenbuterol - food contamination - food safety - β-adrenergic receptors - β-agonist

    Clenbuterol is a steroid-type drug used in respiratory treatments in both humans and animals. However, it has a secondary effect related to the hypertrophy process in muscle and fat reduction. The illegal or bad use of clenbuterol has been reported in several countries, but there is scarce information in South America, where the production and consumption of meat are considerable. In this sense, the present study aimed at evaluating the occurrence of clenbuterol in bovine muscle and liver samples from a high cattle production area of Ecuador in 2015 and 2018. For this purpose, 57–58 samples were evaluated in 2015 and 20 samples in 2018 using the Enzyme-Linked Inmuno Sorbent Assay and ultrahigh-performance liquid chromatography-tandem mass spectrometry. The results showed complained results for clenbuterol in meat samples from both years and 23% (2015) and 85% (2018) of the samples of meat complied the maximum residue level defined by CODEX.

    Efectos de poda y fertilización en los rendimientos de jatropha bajo condiciones de pequeños agricultores en un bosque seco tropical de ecuador
    Cañadas-López, Álvaro ; Rade-Loor, Diana ; Siegmund-Schultze, Marianna ; Vargas-Hernández, Jesús ; Wehenkel, Christian - \ 2020
    Revista Facultad Nacional de Agronomia Medellin 73 (2020)1. - ISSN 0304-2847 - p. 9089 - 9097.
    Biodiesel - Jatropha curcas - Marginal land - Seed productions

    Jatropha seed is a biomass suitable for bioenergy production that can be produced by smallholders, even on marginal lands. However, the current oilseed production is too low to meet the needs of the planned renewable electricity system in the Galapagos Islands. Pruning and fertilization are management options that can be used to increase the dry seed yields. The effects of both treatments were tested in a split-plot design with jatropha trees, which were monitored during a three-year production period. The average seed production was 643±58 kg ha-1 year-1 in the unpruned trees and 696±50 kg ha-1 year-1 in the pruned trees. Although this difference is small, it is expected to increase over time. The pruned trees developed more slowly than the unpruned trees but showed higher (and still increasing) yields at the end of the three-year test period, while the unpruned trees appeared to have reached their maximum production by the second year of the trial. The low fertilizer doses approved by the smallholders did not have a significant impact on the dry seed yield, and the management options that show benefits in the long term are generally not accepted or adopted by them. Cost-effective nutrient enhancement should be investigated, such as inoculation with arbuscular mycorrhizal fungi.

    Mass spectrometry searches using MASST
    Wang, Mingxun ; Jarmusch, Alan K. ; Vargas, Fernando ; Aksenov, Alexander A. ; Gauglitz, Julia M. ; Weldon, Kelly ; Petras, Daniel ; Silva, Ricardo da; Quinn, Robert ; Melnik, Alexey V. ; Hooft, Justin J.J. van der; Caraballo-Rodríguez, Andrés Mauricio ; Nothias, Louis Felix ; Aceves, Christine M. ; Panitchpakdi, Morgan ; Brown, Elizabeth ; Ottavio, Francesca Di; Sikora, Nicole ; Elijah, Emmanuel O. ; Labarta-Bajo, Lara ; Gentry, Emily C. ; Shalapour, Shabnam ; Kyle, Kathleen E. ; Puckett, Sara P. ; Watrous, Jeramie D. ; Carpenter, Carolina S. ; Bouslimani, Amina ; Ernst, Madeleine ; Swafford, Austin D. ; Zúñiga, Elina I. ; Balunas, Marcy J. ; Klassen, Jonathan L. ; Loomba, Rohit ; Knight, Rob ; Bandeira, Nuno ; Dorrestein, Pieter C. - \ 2020
    Nature Biotechnology 38 (2020). - ISSN 1087-0156 - p. 23 - 26.
    Untargeted mass spectrometry-based metabolomics approach unveils molecular changes in raw and processed foods and beverages
    Gauglitz, Julia M. ; Aceves, Christine M. ; Aksenov, Alexander A. ; Aleti, Gajender ; Almaliti, J. ; Bouslimani, A. ; Brown, Elizabeth A. ; Campeau, Anaamika ; Caraballo-Rodríguez, Andrés Mauricio ; Chaar, Rama ; Silva, Ricardo R. da; Demko, Alyssa M. ; Ottavio, Francesca Di; Elijah, Emmanuel ; Ernst, Madeleine ; Ferguson, L.P. ; Holmes, Xavier ; Jarmusch, Alan K. ; Jiang, Lingjing ; Kang, Kyo Bin ; Koester, I. ; Kwan, B. ; Li, Jie ; Li, Yueying ; Melnik, Alexey V. ; Molina-Santiago, Carlos ; Ni, B. ; Oom, Aaron L. ; Panitchpakdi, Morgan W. ; Petras, Daniel ; Quinn, Robert ; Sikora, Nicole ; Spengler, Katharina ; Teke, B. ; Tripathi, Anupriya ; Ul-Hasan, S. ; Hooft, Justin J.J. van der; Vargas, Fernando ; Vrbanac, Alison ; Vu, Anthony Q. ; Wang, Steven C. ; Weldon, K. ; Wilson, K. ; Wozniak, Jacob M. ; Yoon, Michael ; Bandeira, Nuno ; Dorrestein, Pieter C. - \ 2020
    Food Chemistry 302 (2020). - ISSN 0308-8146
    Fermentation - Food - LC-MS/MS - Metabolomics - Molecular networking - Tea - Untargeted mass spectrometry - Yogurt

    In our daily lives, we consume foods that have been transported, stored, prepared, cooked, or otherwise processed by ourselves or others. Food storage and preparation have drastic effects on the chemical composition of foods. Untargeted mass spectrometry analysis of food samples has the potential to increase our chemical understanding of these processes by detecting a broad spectrum of chemicals. We performed a time-based analysis of the chemical changes in foods during common preparations, such as fermentation, brewing, and ripening, using untargeted mass spectrometry and molecular networking. The data analysis workflow presented implements an approach to study changes in food chemistry that can reveal global alterations in chemical profiles, identify changes in abundance, as well as identify specific chemicals and their transformation products. The data generated in this study are publicly available, enabling the replication and re-analysis of these data in isolation, and serve as a baseline dataset for future investigations.

    Fine-grained landuse characterization using ground-based pictures: a deep learning solution based on globally available data
    Srivastava, Shivangi ; Vargas Muñoz, John E. ; Lobry, Sylvain ; Tuia, Devis - \ 2020
    International Journal of Geographical Information Science 34 (2020)6. - ISSN 1365-8816 - p. 1117 - 1136.
    We study the problem of landuse characterization at the urban-object level using deep learning algorithms. Traditionally, this task is performed by surveys or manual photo interpretation, which are expensive and difficult to update regularly. We seek to characterize usages at the single object level and to differentiate classes such as educational institutes, hospitals and religious places by visual cues contained in side-view pictures from Google Street View (GSV). These pictures provide geo-referenced information not only about the material composition of the objects but also about their actual usage, which otherwise is difficult to capture using other classical sources of data such as aerial imagery. Since the GSV database is regularly updated, this allows to consequently update the landuse maps, at lower costs than those of authoritative surveys. Because every urban-object is imaged from a number of viewpoints with street-level pictures, we propose a deep-learning based architecture that accepts arbitrary number of GSV pictures to predict the fine-grained landuse classes at the object level. These classes are taken from OpenStreetMap. A quantitative evaluation of the area of Île-de-France, France shows that our model outperforms other deep learning-based methods, making it a suitable alternative to manual landuse characterization.
    Interactive Coconut Tree Annotation Using Feature Space Projections
    Vargas-Munoz, John E. ; Zhou, Ping ; Falcao, Alexandre X. ; Tuia, Devis - \ 2019
    In: IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium. - IEEE - ISBN 9781538691557 - p. 5718 - 5721.
    The detection and counting of coconut trees in aerial images are important tasks for environment monitoring and post-disaster assessment. Recent deep-learning-based methods can attain accurate results, but they require a reasonably high number of annotated training samples. In order to obtain such large training sets with considerably reduced human effort, we present a semi-automatic sample annotation method based on the 2D t-SNE projection of the sample feature space. The proposed approach can facilitate the construction of effective training sets more efficiently than using the traditional manual annotation, as shown in our experimental results with VHR images from the Kingdom of Tonga.
    Exploring groundwater microbial communities for natural attenuation potential of micropollutants
    Aldas Vargas, A.B. ; Hauptfeld, Tina ; Hermes, G.D.A. ; Atashgahi, S. ; Smidt, H. ; Rijnaarts, H.H.M. ; Sutton, N.B. - \ 2019
    BioRxiv - 29 p.
    Groundwater is a key water resource, with 45.7% of all drinking water globally beingextracted from 15groundwater. Maintaining good groundwater quality is thus crucial to secure drinking water. 16Micropollutants, such as pesticides, threaten groundwater qualitywhich can be mitigated by 17biodegradation.Hence, exploringmicrobial communities in aquifers used for drinking water 18productionis essential for understanding micropollutantsbiodegradation capacity.This study aimed 19at understanding the interaction between groundwater geochemistry, pesticide presence, and 20microbial communities in aquifers used for drinking water production. Two groundwater monitoring 21wellslocated in the northeast of The Netherlands and at 500 m distance from each other were sampled 22in 2014, 2015, 2016 and 2018. In both wells, water was extracted from five discrete depths ranging 23from 13 to 54 m and used to analyze geochemical parameters, pesticide concentrations and microbial 24community dynamics using 16S rRNA gene sequencing and qPCR. Groundwater geochemistry was 25stable throughout the study period and pesticides were heterogeneously distributedat low 26concentrations (μg/L range). Integration of the groundwater chemical and microbial data showed that 27geochemical parameters and pesticides exerted selective pressure on microbial communities. 28Furthermore, microbial communities in both wells showed a more similar composition in the deeper 29part of the aquiferas compared to shallow sections, suggesting vertical differences in hydrological 30connection. This study provides initial insights into microbial communitycomposition and distribution 31in groundwater systems in relation to geochemical parameters. This information can contribute for 32the implementation of bioremediation technologies that guarantee safe drinking water production 33from clean aquifers.
    A user guide to environmental protistology: primers, metabarcoding, sequencing, and analyses
    Geisen, Stefan ; Vaulot, Daniel ; Mahe, Frederic ; Lara, Enrique ; Vargas, Colomban de; Bass, David - \ 2019
    BioRxiv - 34 p.
    Protists – all eukaryotes besides fungi, animals, and plants - represent a major part of the taxonomic and functional diversity of eukaryotic life on the planet and drive many ecosystem processes. However, knowledge of protist communities and their diversity lags behind that of most other groups of organisms, largely due to methodological constraints. While protist communities differ markedly between habitats and biomes, they can be studied in very similar ways. Here we provide a guide to current molecular approaches used for studying protist diversity, with a particular focus on amplicon-based high-throughput sequencing (metabarcoding). We highlight that the choice of suitable primers artificially alters community profiles observed in metabarcoding studies. While there are no true ‘universal’ primers to target all protist taxa as a whole, we identify some primer combinations with a wide taxonomic coverage and provide detailed information on their properties. Although environmental protistan ecological research will probably shift towards PCR-free metagenomics or/and transcriptomic approaches in a near future, metabarcoding will remain the method of choice for in-depth community analyses and taxon inventories in biodiversity surveys and ecological studies, due its great cost-efficiency, sensitivity, and throughput. In this paper we provide a guide for scientists from a broad range of disciplines to implement protists in their ecological analyses
    Evolutionary diversity is associated with wood productivity in Amazonian forests
    Coelho de Souza, Fernanda ; Dexter, Kyle G. ; Phillips, Oliver L. ; Pennington, Toby R. ; Neves, Danilo ; Sullivan, Martin J.P. ; Alvarez-Davila, Esteban ; Alves, Átila ; Amaral, Ieda ; Andrade, Ana ; Aragao, Luis E.O.C. ; Araujo-Murakami, Alejandro ; Arets, Eric J.M.M. ; Arroyo, Luzmilla ; Aymard C, Gerardo A. ; Bánki, Olaf ; Baraloto, Christopher ; Barroso, Jorcely G. ; Boot, Rene G.A. ; Brienen, Roel J.W. ; Brown, Foster ; Camargo, José Luís C. ; Castro, Wendeson ; Chave, Jerome ; Cogollo, Alvaro ; Comiskey, James A. ; Cornejo-Valverde, Fernando ; Costa, Antonio Lola da; Camargo, Plínio B. de; Fiore, Anthony Di; Feldpausch, Ted R. ; Galbraith, David R. ; Gloor, Emanuel ; Goodman, Rosa C. ; Gilpin, Martin ; Herrera, Rafael ; Higuchi, Niro ; Honorio Coronado, Eurídice N. ; Jimenez-Rojas, Eliana ; Killeen, Timothy J. ; Laurance, Susan ; Laurance, William F. ; Lopez-Gonzalez, Gabriela ; Lovejoy, Thomas E. ; Malhi, Yadvinder ; Marimon, Beatriz S. ; Marimon-Junior, Ben Hur ; Mendoza, Casimiro ; Monteagudo-Mendoza, Abel ; Neill, David A. ; Vargas, Percy Núñez ; Peñuela Mora, Maria C. ; Pickavance, Georgia C. ; Pipoly, John J. ; Pitman, Nigel C.A. ; Poorter, Lourens ; Prieto, Adriana ; Ramirez, Freddy ; Roopsind, Anand ; Rudas, Agustin ; Salomão, Rafael P. ; Silva, Natalino ; Silveira, Marcos ; Singh, James ; Stropp, Juliana ; Steege, Hans ter; Terborgh, John ; Thomas-Caesar, Raquel ; Umetsu, Ricardo K. ; Vasquez, Rodolfo V. ; Célia-Vieira, Ima ; Vieira, Simone A. ; Vos, Vincent A. ; Zagt, Roderick J. ; Baker, Timothy R. - \ 2019
    Nature Ecology & Evolution 3 (2019). - ISSN 2397-334X - p. 1754 - 1761.

    Higher levels of taxonomic and evolutionary diversity are expected to maximize ecosystem function, yet their relative importance in driving variation in ecosystem function at large scales in diverse forests is unknown. Using 90 inventory plots across intact, lowland, terra firme, Amazonian forests and a new phylogeny including 526 angiosperm genera, we investigated the association between taxonomic and evolutionary metrics of diversity and two key measures of ecosystem function: aboveground wood productivity and biomass storage. While taxonomic and phylogenetic diversity were not important predictors of variation in biomass, both emerged as independent predictors of wood productivity. Amazon forests that contain greater evolutionary diversity and a higher proportion of rare species have higher productivity. While climatic and edaphic variables are together the strongest predictors of productivity, our results show that the evolutionary diversity of tree species in diverse forest stands also influences productivity. As our models accounted for wood density and tree size, they also suggest that additional, unstudied, evolutionarily correlated traits have significant effects on ecosystem function in tropical forests. Overall, our pan-Amazonian analysis shows that greater phylogenetic diversity translates into higher levels of ecosystem function: tropical forest communities with more distantly related taxa have greater wood productivity.

    Rarity of monodominance in hyperdiverse Amazonian forests
    Steege, Hans Ter; Henkel, Terry W. ; Helal, Nora ; Marimon, Beatriz S. ; Marimon-Junior, Ben Hur ; Huth, Andreas ; Groeneveld, Jürgen ; Sabatier, Daniel ; Souza Coelho, Luiz de; Andrade Lima Filho, Diogenes de; Salomão, Rafael P. ; Amaral, Iêda Leão ; Almeida Matos, Francisca Dionízia de; Castilho, Carolina V. ; Phillips, Oliver L. ; Guevara, Juan Ernesto ; Jesus Veiga Carim, Marcelo de; Cárdenas López, Dairon ; Magnusson, William E. ; Wittmann, Florian ; Irume, Mariana Victória ; Martins, Maria Pires ; Silva Guimarães, José Renan da; Molino, Jean François ; Bánki, Olaf S. ; Piedade, Maria Teresa Fernandez ; Pitman, Nigel C.A. ; Mendoza, Abel Monteagudo ; Ramos, José Ferreira ; Luize, Bruno Garcia ; Moraes de Leão Novo, Evlyn Márcia ; Núñez Vargas, Percy ; Silva, Thiago Sanna Freire ; Venticinque, Eduardo Martins ; Manzatto, Angelo Gilberto ; Reis, Neidiane Farias Costa ; Terborgh, John ; Casula, Katia Regina ; Honorio Coronado, Euridice N. ; Montero, Juan Carlos ; Feldpausch, Ted R. ; Duque, Alvaro ; Costa, Flávia R.C. ; Arboleda, Nicolás Castaño ; Schöngart, Jochen ; Killeen, Timothy J. ; Vasquez, Rodolfo ; Mostacedo, Bonifacio ; Demarchi, Layon O. ; Assis, Rafael L. ; Baraloto, Chris ; Engel, Julien ; Petronelli, Pascal ; Castellanos, Hernán ; Medeiros, Marcelo Brilhante de; Quaresma, Adriano ; Simon, Marcelo Fragomeni ; Andrade, Ana ; Camargo, José Luís ; Laurance, Susan G.W. ; Laurance, William F. ; Rincón, Lorena M. ; Schietti, Juliana ; Sousa, Thaiane R. ; Sousa Farias, Emanuelle de; Lopes, Maria Aparecida ; Magalhães, José Leonardo Lima ; Mendonça Nascimento, Henrique Eduardo ; Lima de Queiroz, Helder ; Aymard C, Gerardo A. ; Brienen, Roel ; Revilla, Juan David Cardenas ; Vieira, Ima Célia Guimarães ; Cintra, Bruno Barçante Ladvocat ; Stevenson, Pablo R. ; Feitosa, Yuri Oliveira ; Duivenvoorden, Joost F. ; Mogollón, Hugo F. ; Araujo-Murakami, Alejandro ; Ferreira, Leandro Valle ; Lozada, José Rafael ; Comiskey, James A. ; Toledo, José Julio de; Damasco, Gabriel ; Dávila, Nállarett ; Draper, Freddie ; García-Villacorta, Roosevelt ; Lopes, Aline ; Vicentini, Alberto ; Alonso, Alfonso ; Dallmeier, Francisco ; Gomes, Vitor H.F. ; Lloyd, Jon ; Neill, David ; Aguiar, Daniel Praia Portela de; Arroyo, Luzmila ; Carvalho, Fernanda Antunes ; Souza, Fernanda Coelho de; Amaral, Dário Dantas do; Feeley, Kenneth J. ; Gribel, Rogerio ; Pansonato, Marcelo Petratti ; Barlow, Jos ; Berenguer, Erika ; Ferreira, Joice ; Fine, Paul V.A. ; Guedes, Marcelino Carneiro ; Jimenez, Eliana M. ; Licona, Juan Carlos ; Peñuela Mora, Maria Cristina ; Villa, Boris ; Cerón, Carlos ; Maas, Paul ; Silveira, Marcos ; Stropp, Juliana ; Thomas, Raquel ; Baker, Tim R. ; Daly, Doug ; Dexter, Kyle G. ; Huamantupa-Chuquimaco, Isau ; Milliken, William ; Pennington, Toby ; Ríos Paredes, Marcos ; Fuentes, Alfredo ; Klitgaard, Bente ; Pena, José Luis Marcelo ; Peres, Carlos A. ; Silman, Miles R. ; Tello, J.S. ; Chave, Jerome ; Cornejo Valverde, Fernando ; Fiore, Anthony Di; Hilário, Renato Richard ; Phillips, Juan Fernando ; Rivas-Torres, Gonzalo ; Andel, Tinde R. van; Hildebrand, Patricio von; Noronha, Janaína Costa ; Barbosa, Edelcilio Marques ; Barbosa, Flávia Rodrigues ; Matos Bonates, Luiz Carlos de; Sá Carpanedo, Rainiellen de; Dávila Doza, Hilda Paulette ; Fonty, Émile ; GómeZárate Z, Ricardo ; Gonzales, Therany ; Gallardo Gonzales, George Pepe ; Hoffman, Bruce ; Junqueira, André Braga ; Malhi, Yadvinder ; Andrade Miranda, Ires Paula de; Pinto, Linder Felipe Mozombite ; Prieto, Adriana ; Jesus Rodrigues, Domingos de; Rudas, Agustín ; Ruschel, Ademir R. ; Silva, Natalino ; Vela, César I.A. ; Vos, Vincent Antoine ; Zent, Egleé L. ; Zent, Stanford ; Weiss Albuquerque, Bianca ; Cano, Angela ; Carrero Márquez, Yrma Andreina ; Correa, Diego F. ; Costa, Janaina Barbosa Pedrosa ; Flores, Bernardo Monteiro ; Galbraith, David ; Holmgren, Milena ; Kalamandeen, Michelle ; Nascimento, Marcelo Trindade ; Oliveira, Alexandre A. ; Ramirez-Angulo, Hirma ; Rocha, Maira ; Scudeller, Veridiana Vizoni ; Sierra, Rodrigo ; Tirado, Milton ; Umaña Medina, Maria Natalia ; Heijden, Geertje van der; Vilanova Torre, Emilio ; Vriesendorp, Corine ; Wang, Ophelia ; Young, Kenneth R. ; Ahuite Reategui, Manuel Augusto ; Baider, Cláudia ; Balslev, Henrik ; Cárdenas, Sasha ; Casas, Luisa Fernanda ; Farfan-Rios, William ; Ferreira, Cid ; Linares-Palomino, Reynaldo ; Mendoza, Casimiro ; Mesones, Italo ; Torres-Lezama, Armando ; Giraldo, Ligia Estela Urrego ; Villarroel, Daniel ; Zagt, Roderick ; Alexiades, Miguel N. ; Oliveira, Edmar Almeida de; Garcia-Cabrera, Karina ; Hernandez, Lionel ; Palacios Cuenca, Walter ; Pansini, Susamar ; Pauletto, Daniela ; Ramirez Arevalo, Freddy ; Sampaio, Adeilza Felipe ; Valderrama Sandoval, Elvis H. ; Valenzuela Gamarra, Luis ; Levesley, Aurora ; Pickavance, Georgia ; Melgaço, Karina - \ 2019
    Scientific Reports 9 (2019). - ISSN 2045-2322

    Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors.

    Real-Time Assembly of Viruslike Nucleocapsids Elucidated at the Single-Particle Level
    Marchetti, Margherita ; Kamsma, Douwe ; Cazares Vargas, Ernesto ; Hernandez García, Armando ; Schoot, Paul van der; Vries, Renko de; Wuite, Gijs J.L. ; Roos, Wouter H. - \ 2019
    Nano Letters 19 (2019)8. - ISSN 1530-6984 - p. 5746 - 5753.
    acoustic force spectroscopy - artificial virus - biophysics - optical tweezers - physical virology - Self-assembly

    While the structure of a multitude of viral particles has been resolved to atomistic detail, their assembly pathways remain largely elusive. Key unresolved issues are particle nucleation, particle growth, and the mode of genome compaction. These issues are difficult to address in bulk approaches and are effectively only accessible by the real-time tracking of assembly dynamics of individual particles. This we do here by studying the assembly into rod-shaped viruslike particles (VLPs) of artificial capsid polypeptides. Using fluorescence optical tweezers, we establish that small oligomers perform one-dimensional diffusion along the DNA. Larger oligomers are immobile and nucleate VLP growth. A multiplexed acoustic force spectroscopy approach reveals that DNA is compacted in regular steps, suggesting packaging via helical wrapping into a nucleocapsid. By reporting how real-time assembly tracking elucidates viral nucleation and growth principles, our work opens the door to a fundamental understanding of the complex assembly pathways of both VLPs and naturally evolved viruses.

    Author Correction: Reproducible, interactive, scalable and extensible microbiome data science using QIIME 2
    Bolyen, Evan ; Rideout, Jai Ram ; Dillon, Matthew R. ; Bokulich, Nicholas A. ; Abnet, Christian C. ; Al-Ghalith, Gabriel A. ; Alexander, Harriet ; Alm, Eric J. ; Arumugam, Manimozhiyan ; Asnicar, Francesco ; Bai, Yang ; Bisanz, Jordan E. ; Bittinger, Kyle ; Brejnrod, Asker ; Brislawn, Colin J. ; Brown, C.T. ; Callahan, Benjamin J. ; Caraballo-Rodríguez, Andrés Mauricio ; Chase, John ; Cope, Emily K. ; Silva, Ricardo Da; Diener, Christian ; Dorrestein, Pieter C. ; Douglas, Gavin M. ; Durall, Daniel M. ; Duvallet, Claire ; Edwardson, Christian F. ; Ernst, Madeleine ; Estaki, Mehrbod ; Fouquier, Jennifer ; Gauglitz, Julia M. ; Gibbons, Sean M. ; Gibson, Deanna L. ; Gonzalez, Antonio ; Gorlick, Kestrel ; Guo, Jiarong ; Hillmann, Benjamin ; Holmes, Susan ; Holste, Hannes ; Huttenhower, Curtis ; Huttley, Gavin A. ; Janssen, Stefan ; Jarmusch, Alan K. ; Jiang, Lingjing ; Kaehler, Benjamin D. ; Kang, Kyo Bin ; Keefe, Christopher R. ; Keim, Paul ; Kelley, Scott T. ; Knights, Dan ; Koester, Irina ; Kosciolek, Tomasz ; Kreps, Jorden ; Langille, Morgan G.I. ; Lee, Joslynn ; Ley, Ruth ; Liu, Yong Xin ; Loftfield, Erikka ; Lozupone, Catherine ; Maher, Massoud ; Marotz, Clarisse ; Martin, Bryan D. ; McDonald, Daniel ; McIver, Lauren J. ; Melnik, Alexey V. ; Metcalf, Jessica L. ; Morgan, Sydney C. ; Morton, Jamie T. ; Naimey, Ahmad Turan ; Navas-Molina, Jose A. ; Nothias, Louis Felix ; Orchanian, Stephanie B. ; Pearson, Talima ; Peoples, Samuel L. ; Petras, Daniel ; Preuss, Mary Lai ; Pruesse, Elmar ; Rasmussen, Lasse Buur ; Rivers, Adam ; Robeson, Michael S. ; Rosenthal, Patrick ; Segata, Nicola ; Shaffer, Michael ; Shiffer, Arron ; Sinha, Rashmi ; Song, Se Jin ; Spear, John R. ; Swafford, Austin D. ; Thompson, Luke R. ; Torres, Pedro J. ; Trinh, Pauline ; Tripathi, Anupriya ; Turnbaugh, Peter J. ; Ul-Hasan, Sabah ; Hooft, Justin J.J. van der; Vargas, Fernando ; Vázquez-Baeza, Yoshiki ; Vogtmann, Emily ; Hippel, Max von; Walters, William ; Wan, Yunhu ; Wang, Mingxun ; Warren, Jonathan ; Weber, Kyle C. ; Williamson, Charles H.D. ; Willis, Amy D. ; Xu, Zhenjiang Zech ; Zaneveld, Jesse R. ; Zhang, Yilong ; Zhu, Qiyun ; Knight, Rob ; Caporaso, J.G. - \ 2019
    Nature Biotechnology (2019). - ISSN 1087-0156

    In the version of this article initially published, some reference citations were incorrect. The three references to Jupyter Notebooks should have cited Kluyver et al. instead of Gonzalez et al. The reference to Qiita should have cited Gonzalez et al. instead of Schloss et al. The reference to mothur should have cited Schloss et al. instead of McMurdie & Holmes. The reference to phyloseq should have cited McMurdie & Holmes instead of Huber et al. The reference to Bioconductor should have cited Huber et al. instead of Franzosa et al. And the reference to the biobakery suite should have cited Franzosa et al. instead of Kluyver et al. The errors have been corrected in the HTML and PDF versions of the article.

    Reproducible, interactive, scalable and extensible microbiome data science using QIIME 2
    Bolyen, Evan ; Rideout, Jai Ram ; Dillon, Matthew R. ; Bokulich, Nicholas A. ; Abnet, Christian C. ; Al-Ghalith, Gabriel A. ; Alexander, Harriet ; Alm, Eric J. ; Arumugam, Manimozhiyan ; Asnicar, Francesco ; Bai, Yang ; Bisanz, Jordan E. ; Bittinger, Kyle ; Brejnrod, Asker ; Brislawn, Colin J. ; Brown, Titus C. ; Callahan, Benjamin J. ; Caraballo-Rodríguez, Andrés Mauricio ; Chase, John ; Cope, Emily K. ; Silva, Ricardo da; Diener, Christian ; Dorrestein, Pieter C. ; Douglas, Gavin M. ; Durall, Daniel M. ; Duvallet, Claire ; Edwardson, Christian F. ; Ernst, Madeleine ; Estaki, Mehrbod ; Fouquier, Jennifer ; Gauglitz, Julia M. ; Gibbons, Sean M. ; Gibson, Deanna L. ; Gonzalez, Antonio ; Gorlick, Kestrel ; Guo, Jiarong ; Hillmann, Benjamin ; Holmes, Susan ; Holste, Hannes ; Huttenhower, Curtis ; Huttley, Gavin A. ; Janssen, Stefan ; Jarmusch, Alan K. ; Jiang, Lingjing ; Kaehler, Benjamin D. ; Kang, Kyo Bin ; Keefe, Christopher R. ; Keim, Paul ; Kelley, Scott T. ; Knights, Dan ; Koester, Irina ; Kosciolek, Tomasz ; Kreps, Jorden ; Langille, Morgan G.I. ; Lee, Joslynn ; Ley, Ruth ; Liu, Yong Xin ; Loftfield, Erikka ; Lozupone, Catherine ; Maher, Massoud ; Marotz, Clarisse ; Martin, Bryan D. ; McDonald, Daniel ; McIver, Lauren J. ; Melnik, Alexey V. ; Metcalf, Jessica L. ; Morgan, Sydney C. ; Morton, Jamie T. ; Naimey, Ahmad Turan ; Navas-Molina, Jose A. ; Nothias, Louis Felix ; Orchanian, Stephanie B. ; Pearson, Talima ; Peoples, Samuel L. ; Petras, Daniel ; Preuss, Mary Lai ; Pruesse, Elmar ; Rasmussen, Lasse Buur ; Rivers, Adam ; Robeson, Michael S. ; Rosenthal, Patrick ; Segata, Nicola ; Shaffer, Michael ; Shiffer, Arron ; Sinha, Rashmi ; Song, Se Jin ; Spear, John R. ; Swafford, Austin D. ; Thompson, Luke R. ; Torres, Pedro J. ; Trinh, Pauline ; Tripathi, Anupriya ; Turnbaugh, Peter J. ; Ul-Hasan, Sabah ; Hooft, Justin J.J. van der; Vargas, Fernando ; Vázquez-Baeza, Yoshiki ; Vogtmann, Emily ; Hippel, Max von; Walters, William ; Wan, Yunhu ; Wang, Mingxun ; Warren, Jonathan ; Weber, Kyle C. ; Williamson, Charles H.D. ; Willis, Amy D. ; Xu, Zhenjiang Zech ; Zaneveld, Jesse R. ; Zhang, Yilong ; Zhu, Qiyun ; Knight, Rob ; Caporaso, J.G. - \ 2019
    Nature Biotechnology 37 (2019)8. - ISSN 1087-0156 - p. 852 - 857.
    Template-Free Self-Assembly of Artificial De Novo Viral Coat Proteins into Nanorods: Effects of Sequence, Concentration, and Temperature
    Vargas, Ernesto Cazares ; Cohen Stuart, Martien A. ; Vries, Renko de; Hernandez-Garcia, Armando - \ 2019
    Chemistry-A European Journal 25 (2019)47. - ISSN 0947-6539 - p. 10975 - 10975.
    artificial viruses - bionanotechnology - protein engineering - self-assembly - supramolecular materials

    The self-assembly of protein polymers is a promising route to prepare sophisticated functional nanostructures. However, the interplay between protein self-assembly by itself and its co-assembly with a template is not well understood. Silk-based protein polymers that co-assemble with DNA to form rod-like artificial viruses are herein developed and the effects of silk block length, concentration, and temperature in the self-assembly of the proteins alone are characterized by using a combination of bulk dynamic light scattering (DLS) and single-molecule atomic force microscopy (AFM). Protein nanorods were slowly formed (up to hours) through the interaction of the silk-like blocks. The proteins present a silk-length dependent critical elongation concentration, and above it the amount and size of nanorods rapidly increase. Temperature-dependent light scattering data was adequately fitted into a cooperative model of nucleation–elongation. These results are also important to understand the self-assembly of designed viral coat proteins with DNA templates to form artificial virus-like particles and help us to define general guidelines to design proteins with the ability to precisely organize matter at the nanoscale.

    Understanding urban landuse from the above and ground perspectives: A deep learning, multimodal solution
    Srivastava, Shivangi ; Vargas-Muñoz, John E. ; Tuia, Devis - \ 2019
    Remote Sensing of Environment 228 (2019). - ISSN 0034-4257 - p. 129 - 143.
    Landuse characterization is important for urban planning. It is traditionally performed with field surveys or manual photo interpretation, two practices that are time-consuming and labor-intensive. Therefore, we aim to automate landuse mapping at the urban-object level with a deep learning approach based on data from multiple sources (or modalities). We consider two image modalities: overhead imagery from Google Maps and ensembles of ground-based pictures (side-views) per urban-object from Google Street View (GSV). These modalities bring complementary visual information pertaining to the urban-objects. We propose an end-to-end trainable model, which uses OpenStreetMap annotations as labels. The model can accommodate a variable number of GSV pictures for the ground-based branch and can also function in the absence of ground pictures at prediction time. We test the effectiveness of our model over the area of Île-de-France, France, and test its generalization abilities on a set of urban-objects from the city of Nantes, France. Our proposed multimodal Convolutional Neural Network achieves considerably higher accuracies than methods that use a single image modality, making it suitable for automatic landuse map updates. Additionally, our approach could be easily scaled to multiple cities, because it is based on data sources available for many cities worldwide.
    Exploratory monitoring of the quality and authenticity of commercial honey in Ecuador
    Salvador, Lorena ; Guijarro, Michelle ; Rubio, Daniela ; Aucatoma, Bolívar ; Guillén, Tanya ; Jentzsch, Paul Vargas ; Ciobotă, Valerian ; Stolker, Linda ; Ulic, Sonia ; Vásquez, Luis ; Garrido, Patricia ; Bravo, Juan ; Guerrero, Luis Ramos - \ 2019
    Foods 8 (2019)3. - ISSN 2304-8158
    Adulteration - Chemometric - Honey - Infrared spectroscopy - Raman spectroscopy

    Honey is one of the oldest sweetening foods and has economic importance, making this product attractive to adulteration with cheap sugars. This can cause a critical problem in the honey industry and a possible health risk. The present work has the aim of evaluating the authenticity of honey commercialized in two different provinces of Ecuador (Pichincha and Loja) by performing physicochemical and spectroscopic analyses. For this study 25 samples were collected from different places and markets and characterized by water, sucrose, reducing sugars and electric conductivity measurement. Also, their Raman and Infrared (IR) spectra were recorded and analysed using a Principal Component Analysis (PCA) in order to verify the quality of the honeys. In addition, a screening of several pesticides was performed in order to verify possible chemical threats to human health and honey bees. It was found that 8 samples have a deviation from the Standard established parameters. Two of them have a high difference in the content of sucrose and reducing sugars, which are located deviated from all the other samples in the PCA of the applied vibrational spectroscopy (IR/Raman), shaping two clear clusters. The results show that Raman and IR spectroscopy is appropriate techniques for the quality control of honey and correlates well with the physicochemical analyses.

    Using remote sensing and ecosystem accounting to assess changes in ecosystems, with an illustration for the Orinoco river basin
    Vargas, Leonardo - \ 2019
    Wageningen University. Promotor(en): L.G. Hein, co-promotor(en): L. Willemen. - Wageningen : Wageningen University - ISBN 9789463434089 - 130

    A further step in understanding the connections between ecosystems and the economy has been the development of ecosystem accounting. Ecosystem accounting assess changes on ecosystems and ecosystem services using cartographical and statistic information. However, such information is often non-existent or scarce, inaccessible and expensive. Remote sensing provides timely data over large coverages and can be a useful source of spatially explicit data at relatively low cost. This thesis shows the use of MODIS land surface products to support ecosystem accounting in the assessment of unsustainable changes in ecosystems. Examples of how the MODIS products can be used to populate the extent, condition and capacity accounts have been demonstrated in the chapters of this thesis. Moreover, examples of how ecosystem accounting can be combined with other multidisciplinary quantitative frameworks and on how ecosystem accounting can be applied in the assessment of human-managed ecosystems have been also provided. The potential use of the moderate resolution sensor VIIRS and the high-resolution sensors on board the Landsat 8 and Sentinel satellites as a source of spatially explicit information to populate accounts was recognized in the synthesis chapter. Moreover, the potential use of other MODIS products such as the atmosphere, cryosphere and ocean products to expand the assessment of other ecological areas such as the atmosphere and the sea were identified in the synthesis chapter.

    Correcting rural building annotations in OpenStreetMap using convolutional neural networks
    Vargas-Muñoz, John E. ; Lobry, Sylvain ; Falcão, Alexandre X. ; Tuia, Devis - \ 2019
    ISPRS Journal of Photogrammetry and Remote Sensing 147 (2019). - ISSN 0924-2716 - p. 283 - 293.
    Rural building mapping is paramount to support demographic studies and plan actions in response to crisis that affect those areas. Rural building annotations exist in OpenStreetMap (OSM), but their quality and quantity are not sufficient for training models that can create accurate rural building maps. The problems with these annotations essentially fall into three categories: (i) most commonly, many annotations are geometrically misaligned with the updated imagery; (ii) some annotations do not correspond to buildings in the images (they are misannotations or the buildings have been destroyed); and (iii) some annotations are missing for buildings in the images (the buildings were never annotated or were built between subsequent image acquisitions). First, we propose a method based on Markov Random Field (MRF) to align the buildings with their annotations. The method maximizes the correlation between annotations and a building probability map while enforcing that nearby buildings have similar alignment vectors. Second, the annotations with no evidence in the building probability map are removed. Third, we present a method to detect non-annotated buildings with predefined shapes and add their annotation. The proposed methodology shows considerable improvement in accuracy of the OSM annotations for two regions of Tanzania and Zimbabwe, being more accurate than state-of-the-art baselines.
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