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.

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Narrow-wide-row planting pattern increases the radiation use efficiency and seed yield of intercrop species in relay-intercropping system
Raza, Muhammad Ali ; Feng, Ling Yang ; Werf, Wopke van der; Cai, Gao Ren ; Khalid, Muhammad Hayder Bin ; Iqbal, Nasir ; Hassan, Muhammad Jawad ; Meraj, Tehseen Ahmad ; Naeem, Muhammd ; Khan, Imran ; Ur Rehman, Sana ; Ansar, Muhammad ; Ahmed, Mukhtar ; Yang, Feng ; Yang, Wenyu - \ 2019
Food and Energy Security 8 (2019)3. - ISSN 2048-3694
competition - intercropping - land equivalent ratio - radiation use efficiency

Planting arrangements affect radiation use efficiency (RUE) and competitiveness of intercrop species in intercropping systems. Here, we reveal that narrow-wide-row planting arrangement in maize-soybean relay-intercropping system increases the dry matter and competitiveness of soybean, increased the RUE of maize and soybean, and compensates the yield loss of maize by substantially increasing the yield of soybean. In this field study, maize was planted with soybean in different planting arrangements (P1, 20:180, P2, 40:160; P3, 60:140, and P4, 80:120) of relay intercropping, all the relay-intercropping treatments were compared with sole crops of maize (SM) and soybean (SS). Results showed that P1 improved the total RUE 3.26 g/MJ (maize RUE + soybean RUE) of maize and soybean in relay-intercropping system. Compared to P4, treatment P1 increased the soybean competition ratio (CR) values (by 55%) but reduced the maize CR values (by 29%), which in turn significantly improved the yield of soybean by maintaining the maize yield. Generally, in P1, soybean produced 82% of SS yield, and maize produced 88% of SM yield, and it achieved the land equivalent ratio of 1.7. These results suggest that by maintaining the appropriate planting distances between maize and soybean we can improve the competitiveness and yield of intercrop species in relay-intercropping system.

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.
Importance of snow and glacier meltwater for agriculture on the Indo-Gangetic Plain
Biemans, H. ; Siderius, C. ; Lutz, A.F. ; Nepal, S. ; Ahmad, B. ; Hassan, T. ; Bloh, W. von; Wijngaard, R.R. ; Wester, P. ; Shrestha, A.B. ; Immerzeel, W.W. - \ 2019
Nature Sustainability 2 (2019)7. - ISSN 2398-9629 - p. 594 - 601.

Densely populated floodplains downstream of Asia’s mountain ranges depend heavily on mountain water resources, in particular for irrigation. An intensive and complex multi-cropping irrigated agricultural system has developed here to optimize the use of these mountain water resources in conjunction with monsoonal rainfall. Snow and glacier melt thereby modulate the seasonal pattern of river flows and, together with groundwater, provide water when rainfall is scarce. Climate change is expected to weaken this modulating effect, with potentially strong effects on food production in one of the world’s breadbaskets. Here we quantify the space-, time- and crop-specific dependence of agriculture in the Indo-Gangetic Plains on mountain water resources, using a coupled state-of-the-art, high-resolution, cryosphere–hydrology–crop model. We show that dependence varies strongly in space and time and is highest in the Indus basin, where in the pre-monsoon season up to 60% of the total irrigation withdrawals originate from mountain snow and glacier melt, and that it contributes an additional 11% to total crop production. Although dependence in the floodplains of the Ganges is comparatively lower, meltwater is still essential during the dry season, in particular for crops such as sugar cane. The dependency on meltwater in the Brahmaputra is negligible. In total, 129 million farmers in the Indus and Ganges substantially depend on snow and glacier melt for their livelihoods. Snow and glacier melt provides enough water to grow food crops to sustain a balanced diet for 38 million people. These findings provide important information for agricultural and climate change adaptation policies in a climate change hot spot where shifts in water availability and demand are projected as a result of climate change and socio-economic growth.

Plant viruses in plant molecular pharming: Toward the use of enveloped viruses
Ibrahim, Ahmad ; Odon, Valerie ; Kormelink, Richard - \ 2019
Frontiers in Plant Science 10 (2019). - ISSN 1664-462X
Biotechnology - Non-enveloped viruses - Plant molecular pharming - Plant rhabdoviruses - Recombinant vaccines - Virus like particles

Plant molecular pharming has emerged as a reliable platform for recombinant protein expression providing a safe and low-cost alternative to bacterial and mammalian cells-based systems. Simultaneously, plant viruses have evolved from pathogens to molecular tools for recombinant protein expression, chimaeric viral vaccine production, and lately, as nanoagents for drug delivery. This review summarizes the genesis of viral vectors and agroinfection, the development of non-enveloped viruses for various biotechnological applications, and the on-going research on enveloped plant viruses.

Soil nematode abundance and functional group composition at a global scale
Hoogen, Johan Van Den; Geisen, Stefan ; Routh, Devin ; Ferris, Howard ; Traunspurger, Walter ; Wardle, David A. ; Goede, Ron G.M. De; Adams, Byron J. ; Ahmad, Wasim ; Andriuzzi, Walter S. ; Korthals, Gerard ; Quist, Casper W. ; Putten, Wim Van Der; Wilschut, Rutger - \ 2019
Nature 572 (2019)7768. - ISSN 0028-0836 - p. 194 - 198.
Soil organisms are a crucial part of the terrestrial biosphere. Despite their importance for ecosystem functioning, few quantitative, spatially explicit models of the active belowground community currently exist. In particular, nematodes are the most abundant animals on Earth, filling all trophic levels in the soil food web. Here we use 6,759 georeferenced samples to generate a mechanistic understanding of the patterns of the global abundance of nematodes in the soil and the composition of their functional groups. The resulting maps show that 4.4 ± 0.64 × 1020 nematodes (with a total biomass of approximately 0.3 gigatonnes) inhabit surface soils across the world, with higher abundances in sub-Arctic regions (38% of total) than in temperate (24%) or tropical (21%) regions. Regional variations in these global trends also provide insights into local patterns of soil fertility and functioning. These high-resolution models provide the first steps towards representing soil ecological processes in global biogeochemical models and will enable the prediction of elemental cycling under current and future climate scenarios
Arsenic in Argentina : Technologies for arsenic removal from groundwater sources, investment costs and waste management practices
Litter, Marta I. ; Ingallinella, Ana M. ; Olmos, Valentina ; Savio, Marianela ; Difeo, Gonzalo ; Botto, Lía ; Torres, Elsa Mónica Farfán ; Taylor, Sergio ; Frangie, Sofía ; Herkovits, Jorge ; Schalamuk, Isidoro ; González, María José ; Berardozzi, Eliana ; García Einschlag, Fernando S. ; Bhattacharya, Prosun ; Ahmad, Arslan - \ 2019
Science of the Total Environment 690 (2019). - ISSN 0048-9697 - p. 778 - 789.
Argentina - Arsenic - Drinking water - Mitigation - Removal technologies

An overview about the presence of arsenic (As) in groundwaters of Argentina, made by a transdisciplinary group of experts is presented. In this second part, the conventional and emerging technologies for As removal, management of wastes, and the initial investment costs of the proposed technologies, with emphasis on developments of local groups are described. Successful examples of real application of conventional and emerging technologies for As removal in waters for human consumption, for medium, small and rural and periurban communities are reported. In the country, the two most applied technologies for arsenic removal at a real scale are reverse osmosis and coagulation-adsorption-filtration processes using iron or aluminum salts or polyelectrolytes as coagulants. A decision tree to evaluate the possible technologies to be applied, based on the population size, the quality of the water and its intended use, is presented, including preliminary and indicative investment costs. Finally, a section discussing the treatment and final disposal of the liquid, semiliquid and solid wastes, generated by the application of the most used technologies, is included. Conclusions and recommendations, especially for isolated rural and periurban regions, have been added.

The need for bottom-up assessments of climate risks and adaptation in climate-sensitive regions
Conway, Declan ; Nicholls, Robert J. ; Brown, Sally ; Tebboth, Mark G.L. ; Adger, William Neil ; Ahmad, Bashir ; Biemans, Hester ; Crick, Florence ; Lutz, Arthur F. ; Campos, Ricardo Safra De; Said, Mohammed ; Singh, Chandni ; Zaroug, Modathir Abdalla Hassan ; Ludi, Eva ; New, Mark ; Wester, Philippus - \ 2019
Nature Climate Change 9 (2019)7. - ISSN 1758-678X - p. 503 - 511.

Studies of climate change at specific intervals of future warming have primarily been addressed through top-down approaches using climate projections and modelled impacts. In contrast, bottom-up approaches focus on the recent past and present vulnerability. Here, we examine climate signals at different increments of warming and consider the need to reconcile top-down and bottom-up approaches. We synthesise insights from recent studies in three climate-sensitive systems where change is a defining feature of the human-environment system. Whilst top-down and bottom-up approaches generate complementary insights into who and what is at risk, integrating their results is a much-needed step towards developing relevant information to address the needs of immediate adaptation decisions.

Characteristics of Fe and Mn bearing precipitates generated by Fe(II) and Mn(II) co-oxidation with O2, MnO4 and HOCl in the presence of groundwater ions
Ahmad, Arslan ; Wal, Albert van der; Bhattacharya, Prosun ; Genuchten, Case M. van - \ 2019
Water Research 161 (2019). - ISSN 0043-1354 - p. 505 - 516.
Drinking water - Filtration - Groundwater treatment - Iron and manganese oxidation and precipitation - Mn and Fe removal - X-ray absorption spectroscopy

In this work, we combined macroscopic measurements of precipitate aggregation and chemical composition (Mn/Fe solids ratio) with Fe and Mn K-edge X-ray absorption spectroscopy to investigate the solids formed by co-oxidation of Fe(II) and Mn(II) with O2, MnO4, and HOCl in the presence of groundwater ions. In the absence of the strongly sorbing oxyanions, phosphate (P) and silicate (Si), and calcium (Ca), O2 and HOCl produced suspensions that aggregated rapidly, whereas co-oxidation of Fe(II) and Mn(II) by MnO4 generated colloidally stable suspensions. The aggregation of all suspensions decreased in P and Si solutions, but Ca counteracted these oxyanion effects. The speciation of oxidized Fe and Mn in the absence of P and Si also depended on the oxidant, with O2 producing Mn(III)-incorporated lepidocrocite (Mn/Fe = 0.01–0.02 mol/mol), HOCl producing Mn(III)-incorporated hydrous ferric oxide (HFO) (Mn/Fe = 0.08 mol/mol), and MnO4 producing poorly-ordered MnO2 and HFO (Mn/Fe > 0.5 mol/mol). In general, the presence of P and Si decreased the crystallinity of the Fe(III) phase and increased the Mn/Fe solids ratio, which was found by Mn K-edge XAS analysis to be due to an increase in surface-bound Mn(II). By contrast, Ca decreased the Mn/Fe solids ratio and decreased the fraction of Mn(II) associated with the solids, suggesting that Ca and Mn(II) compete for sorption sites. Based on these results, we discuss strategies to optimize the design (i.e. filter bed operation and chemical dosing) of water treatment plants that aim to remove Fe(II) and Mn(II) by co-oxidation.

Estimation of Muscle Scores of Live Pigs Using a Kinect Camera
Alsahaf, Ahmad ; Azzopardi, George ; Ducro, Bart ; Hanenberg, Egiel ; Veerkamp, Roel F. ; Petkov, Nicolai - \ 2019
IEEE Access 7 (2019). - ISSN 2169-3536 - p. 52238 - 52245.
Computer vision - machine learning - precision farming - RGB-D imaging

The muscle grading of livestock is a primary component of valuation in the meat industry. In pigs, the muscularity of a live animal is traditionally estimated by visual and tactile inspection from an experienced assessor. In addition to being a time-consuming process, scoring of this kind suffers from inconsistencies inherent to the subjectivity of human assessment. On the other hand, accurate, computer-driven methods for carcass composition estimation, such as magnetic resonance imaging (MRI) and computed tomography scans (CT-scans), are expensive and cumbersome to both the animals and their handlers. In this paper, we propose a method that is fast, inexpensive, and non-invasive for estimating the muscularity of live pigs, using RGB-D computer vision and machine learning. We used morphological features extracted from the depth images of pigs to train a classifier that estimates the muscle scores that are likely to be given by a human assessor. The depth images were obtained from a Kinect v1 camera which was placed over an aisle through which the pigs passed freely. The data came from 3246 pigs, each having 20 depth images, and a muscle score from 1 to 7 (reduced later to 5 scores) assigned by an experienced assessor. The classification based on morphological features of the pig's body shape-using a gradient boosted classifier-resulted in a mean absolute error of 0.65 in tenfold cross-validation. Notably, the majority of the errors corresponded to pigs being classified as having muscle scores adjacent to the groundtruth labels given by the assessor. According to the end users of this application, the proposed approach could be used to replace expert assessors at the farm.

Rising rural body-mass index is the main driver of the global obesity epidemic in adults
Bixby, Honor ; Bentham, James ; Zhou, Bin ; Cesare, Mariachiara Di; Paciorek, Christopher J. ; Bennett, James E. ; Taddei, Cristina ; Stevens, Gretchen A. ; Rodriguez-Martinez, Andrea ; Carrillo-Larco, Rodrigo M. ; Khang, Young Ho ; Sorić, Maroje ; Gregg, Edward W. ; Miranda, J.J. ; Bhutta, Zulfiqar A. ; Savin, Stefan ; Sophiea, Marisa K. ; Iurilli, Maria L.C. ; Solomon, Bethlehem D. ; Cowan, Melanie J. ; Riley, Leanne M. ; Danaei, Goodarz ; Bovet, Pascal ; Chirita-Emandi, Adela ; Hambleton, Ian R. ; Hayes, Alison J. ; Ikeda, Nayu ; Kengne, Andre P. ; Laxmaiah, Avula ; Li, Yanping ; McGarvey, Stephen T. ; Mostafa, Aya ; Neovius, Martin ; Starc, Gregor ; Zainuddin, Ahmad A. ; Abarca-Gómez, Leandra ; Abdeen, Ziad A. ; Abdrakhmanova, Shynar ; Abdul Ghaffar, Suhaila ; Abdul Hamid, Zargar ; Abubakar Garba, Jamila ; Ferrieres, Jean ; He, Yuna ; Jacobs, Jeremy M. ; Kromhout, Daan ; Ma, Guansheng ; Visser, Marjolein ; Wang, Qian ; Wang, Ya Xing ; Wang, Ying Wei - \ 2019
Nature 569 (2019)7755. - ISSN 0028-0836 - p. 260 - 264.

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3–6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017—and more than 80% in some low- and middle-income regions—was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing—and in some countries reversal—of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.

Arsenic in Argentina: Occurrence, human health, legislation and determination
Litter, Marta I. ; Ingallinella, Ana M. ; Olmos, Valentina ; Savio, Marianela ; Difeo, Gonzalo ; Botto, Lía ; Farfán Torres, Elsa Mónica ; Taylor, Sergio ; Frangie, Sofía ; Herkovits, Jorge ; Schalamuk, Isidoro ; González, María José ; Berardozzi, Eliana ; García Einschlag, Fernando S. ; Bhattacharya, Prosun ; Ahmad, Arslan - \ 2019
Science of the Total Environment 676 (2019). - ISSN 0048-9697 - p. 756 - 766.
Analytical determination - Argentina - Arsenic - Health - Occurrence - Regulations

An overview about the presence of arsenic (As) in groundwaters of Argentina, made by a transdisciplinary group of experts is presented. Aspects on As occurrence, effects of As on human health, regulations regarding the maximum allowable amount of As in drinking water as well as bottled water, and analytical techniques for As determination are presented. The most affected region in Argentina is the Chaco-Pampean plain, covering around 10 million km 2 , where approximately 88% of 86 groundwater samples collected in 2007 exceeded the World Health Organization (WHO) guideline value. In the Salí river basin, As concentrations ranged from 11.4 to 1660 μg/L, with 100% of the samples above the WHO guideline value. In the Argentine Altiplano (Puna) and Subandean valleys, 61% of 62 samples collected from surface and groundwaters exceeded the WHO limit. Thus, it can be estimated that, at present, the population at risk in Argentina reaches around four million people. Pathologies derived from the chronic consumption of As, the metabolism of As in the human body and the effects of the different As chemical forms, gathered under the name HACRE (hidroarsenicismo crónico regional endémico in Spanish, for chronic regional endemic hydroarsenicism) are described. Regarding the regulations, the 10 μg/L limit recommended by the WHO and the United States Environmental Protection Agency has been incorporated in the Argentine Food Code, but the application is still on hold. In addition, there is disparity regarding the maximal admitted values in several provinces. Considerations about the As concentrations in bottled water are also presented. A survey indicates that there are several Argentine laboratories with the suitable equipment for As determination at 10 μg/L, although 66% of them are concentrated in Buenos Aires City, and in the Santa Fe, Córdoba and Buenos Aires provinces. Conclusions and recommendations of this first part are provided.

Patterns of outdoor exposure to heat in three South Asian cities
Jacobs, Cor ; Singh, Tanya ; Gorti, Ganesh ; Iftikhar, Usman ; Saeed, Salar ; Syed, Abu ; Abbas, Farhat ; Ahmad, Bashir ; Bhadwal, Suruchi ; Siderius, Christian - \ 2019
Science of the Total Environment 674 (2019). - ISSN 0048-9697 - p. 264 - 278.
Heat exposure - HI - South Asia - Urban heat island - UTCI - WBGT

Low socio-economic status has been widely recognized as a significant factor in enhancing a person's vulnerability to climate change including vulnerability to changes in temperature. Yet, little is known about exposure to heat within cities in developing countries, and even less about exposure within informal neighbourhoods in those countries. This paper presents an assessment of exposure to outdoor heat in the South Asian cities Delhi, Dhaka, and Faisalabad. The temporal evolution of exposure to heat is evaluated, as well as intra-urban differences, using meteorological measurements from mobile and stationary devices (April–September 2016). Exposure to heat is compared between low-income and other neighbourhoods in these cities. Results are expressed in terms of air temperature and in terms of the thermal indices Heat Index (HI), Wet Bulb Globe Temperature (WBGT) and Universal Thermal Climate Index (UTCI) at walking level. Conditions classified as dangerous to very dangerous, and likely to impede productivity, are observed almost every day of the measurement period during daytime, even when air temperature drops after the onset of the monsoon. It is recommended to cast heat warnings in terms of thermal indices instead of just temperature. Our results nuance the idea that people living in informal neighbourhoods are consistently more exposed to heat than people living in more prosperous neighbourhoods. During night-time, exposure does tend to be enhanced in densely-built informal neighbourhoods, but not if the low-income neighbourhoods are more open, or if they are embedded in green/blue areas.

Uncertainties of prediction accuracy in shallow landslide modeling : Sample size and raster resolution
Shirzadi, Ataollah ; Solaimani, Karim ; Roshan, Mahmood Habibnejad ; Kavian, Ataollah ; Chapi, Kamran ; Shahabi, Himan ; Keesstra, Saskia ; Ahmad, Baharin Bin ; Bui, Dieu Tien - \ 2019
Catena 178 (2019). - ISSN 0341-8162 - p. 172 - 188.
Alternating decision tree - GIS - Landslide susceptibility - Pixel and sample size - Uncertainty

Understanding landslide characteristics such as their locations, dimensions, and spatial distribution is of highly importance in landslide modeling and prediction. The main objective of this study was to assess the effect of different sample sizes and raster resolutions in landslide susceptibility modeling and prediction accuracy of shallow landslides. In this regard, the Bijar region of the Kurdistan province (Iran) was selected as a case study. Accordingly, a total of 20 landslide conditioning factors were considered with six different raster resolutions (10 m, 15 m, 20 m, 30 m, 50 m, and 100 m) and four different sample sizes (60/40%, 70/30%, 80/20%, and 90/10%) were investigated. The merit of each conditioning factors was assessed using the Information Gain Ratio (IGR) technique, whereas Alternating decision tree (ADTree), which has been rarely explored for landslide modeling, was used for building models. Performance of the models was assessed using the area under the ROC curve (AUROC), sensitivity, specificity, accuracy, kappa and RMSE criteria. The results show that with increasing the number of training pixels in the modeling process, the accuracy is increased. Findings also indicate that for the sample sizes of 60/40% (AUROC = 0.800) and 70/30% (AUROC = 0.899), the highest prediction accuracy is derived with the raster resolution of 10 m. With the raster resolution of 20 m, the highest prediction accuracy for the sample size of 80/20% (AUROC = 0.871) and 90/10% (AUROC = 0.864). These outcomes provide a guideline for future research enabling researchers to select an optimal data resolution for landslide hazard modeling.

Dynamic heterogeneity in complex interfaces of soft interface-dominated materials
Sagis, Leonard M.C. ; Liu, Bingxue ; Li, Yuan ; Essers, Jeffrey ; Yang, Jack ; Moghimikheirabadi, Ahmad ; Hinderink, Emma ; Berton-Carabin, Claire ; Schroen, Karin - \ 2019
Scientific Reports 9 (2019)1. - ISSN 2045-2322

Complex interfaces stabilized by proteins, polymers or nanoparticles, have a much richer dynamics than those stabilized by simple surfactants. By subjecting fluid-fluid interfaces to step extension-compression deformations, we show that in general these complex interfaces have dynamic heterogeneity in their relaxation response that is well described by a Kohlrausch-Williams-Watts function, with stretch exponent β between 0.4–0.6 for extension, and 0.6–1.0 for compression. The difference in β between expansion and compression points to an asymmetry in the dynamics. Using atomic force microscopy and simulations we prove that the dynamic heterogeneity is intimately related to interfacial structural heterogeneity and show that the dominant mode for stretched exponential relaxation is momentum transfer between bulk and interface, a mechanism which has so far largely been ignored in experimental surface rheology. We describe how its rate constant can be determined using molecular dynamics simulations. These interfaces clearly behave like disordered viscoelastic solids and need to be described substantially different from the 2d homogeneous viscoelastic fluids typically formed by simple surfactants.

Gas-liquid phase equilibrium of a model Langmuir monolayer captured by a multiscale approach
Moghimikheirabadi, Ahmad ; Sagis, Leonard M.C. ; Kröger, Martin ; Ilg, Patrick - \ 2019
Physical Chemistry Chemical Physics 21 (2019)5. - ISSN 1463-9076 - p. 2295 - 2306.

The gas-liquid expanded phase transition of a Langmuir monolayer happens at very low surface concentrations which makes this phenomenon extremely expensive to explore in finite three-dimensional (3D) atomistic simulations. Starting with a 3D model reference system of amphiphilic surfactants at a 2D vapor-liquid interface, we apply our recently developed approach (Phys. Chem. Chem. Phys., 2018, 20, 16238) and map the entire system to an effective 2D system of surfactant center-of-masses projected onto the interface plane. The coarse-grained interaction potential obtained via a force-matching scheme from the 3D simulations is then used to predict the 2D gas-liquid phase equilibrium of the corresponding Langmuir monolayer. Monte Carlo simulations in the Gibbs ensemble are performed to calculate areal densities, chemical potentials and surface pressures of the gaseous and liquid coexisting phases within the monolayer. We compare these simulations to the results of a 2D density functional approach based on Weeks-Chandler-Anderson perturbation theory. We furthermore use this approach to determine the density profiles across the equilibrium gas-liquid dividing line and the corresponding line tensions.

Arsenic in Drinking Water : Is 10 μg/L a Safe Limit?
Ahmad, Arslan ; Bhattacharya, Prosun - \ 2019
Current Pollution Reports 5 (2019)1. - ISSN 2198-6592 - p. 1 - 3.
Arsenic - Drinking Water - Health Effects - Water Utilities
Arsenic (As) is a naturally occurring element in the Earth’s crust. Both anthropogenic and natural processes can release As into sources for drinking water supply. A substantial epidemiological evidence is available to support that the chronic exposure to high concentrations in drinking water (> 10 μg/L) is associated with several detrimental effects on human health including skin lesions [1] and cancer of the lung [2], bladder [3], kidney [4], and liver [4]. Furthermore, dermatological, developmental, neurological [5], respiratory [6], cardiovascular [7], immunological [8], and endocrine effects [9] as a result of chronic exposure to high As concentrations have been reported. However, there remains considerable uncertainty on the chronic risks due to As exposure at low concentrations (< 10 μg/L) and the shape of the dose-response relationship [10, 11]. It is therefore crucial to question whether the 10 μg/L limit ensures protection of human health from the adverse health effects of As.
Multispectral camera as spatio-spectrophotometer under uncontrolled illumination
Khan, Haris Ahmad ; Thomas, Jean Baptiste ; Hardeberg, Jon Yngve ; Laligant, Olivier - \ 2019
Optics Express 27 (2019)2. - ISSN 1094-4087 - p. 1051 - 1070.

Multispectral constancy enables the illuminant invariant representation of multispectral data. This article proposes an experimental investigation of multispectral constancy through the use of multispectral camera as a spectrophotometer for the reconstruction of surface reflectance. Three images with varying illuminations are captured and the spectra of material surfaces is reconstructed. The acquired images are transformed into canonical representation through the use of diagonal transform and spectral adaptation transform. Experimental results show that use of multispectral constancy is beneficial for both filter-wheel and snapshot multispectral cameras. The proposed concept is robust to errors in illuminant estimation and is able to perform well with linear spectral reconstruction method. This work makes us one step closer to the use of multispectral imaging for computer vision.

Input Selection of Wavelet-Coupled Neural Network Models for Rainfall-Runoff Modelling
Shoaib, Muhammad ; Shamseldin, Asaad Y. ; Khan, Sher ; Sultan, Muhammad ; Ahmad, Fiaz ; Sultan, Tahir ; Dahri, Zakir Hussain ; Ali, Irfan - \ 2019
Water Resources Management 33 (2019)3. - ISSN 0920-4741 - p. 955 - 973.
Artificial neural network - Discrete wavelet transformation - Rainfall-runoff modelling - Wavelet sub-series

The use of wavelet-coupled data-driven models is increasing in the field of hydrological modelling. However, wavelet-coupled artificial neural network (ANN) models inherit the disadvantages of containing more complex structure and enhanced simulation time as a result of use of increased multiple input sub-series obtained by the wavelet transformation (WT). So, the identification of dominant wavelet sub-series containing significant information regarding the hydrological system and subsequent use of those dominant sub-series only as input is crucial for the development of wavelet-coupled ANN models. This study is therefore conducted to evaluate various approaches for selection of dominant wavelet sub-series and their effect on other critical issues of suitable wavelet function, decomposition level and input vector for the development of wavelet-coupled rainfall-runoff models. Four different approaches to identify dominant wavelet sub-series, ten different wavelet functions, nine decomposition levels, and five different input vectors are considered in the present study. Out of four tested approaches, the study advocates the use of relative weight analysis (RWA) for the selection of dominant input wavelet sub-series in the development of wavelet-coupled models. The db8 and the dmey (Discrete approximation of Meyer) wavelet functions at level nine were found to provide the best performance with the RWA approach.

Meta-analysis of genome-wide association studies of aggressive and chronic periodontitis identifies two novel risk loci
Munz, Matthias ; Richter, Gesa M. ; Loos, Bruno G. ; Jepsen, Søren ; Divaris, Kimon ; Offenbacher, Steven ; Teumer, Alexander ; Holtfreter, Birte ; Kocher, Thomas ; Bruckmann, Corinna ; Jockel-Schneider, Yvonne ; Graetz, Christian ; Ahmad, Ilyas ; Staufenbiel, Ingmar ; Velde, Nathalie Van Der; Uitterlinden, André G. ; Groot, Lisette C.P.G.M. De; Wellmann, Jürgen ; Berger, Klaus ; Krone, Bastian ; Hoffmann, Per ; Laudes, Matthias ; Lieb, Wolfgang ; Franke, Andre ; Erdmann, Jeanette ; Dommisch, Henrik ; Schaefer, Arne S. - \ 2019
European Journal of Human Genetics 27 (2019)1. - ISSN 1018-4813 - p. 102 - 113.
Periodontitis is one of the most common inflammatory diseases, with a prevalence of 11% worldwide for the severe forms and an estimated heritability of 50%. It is classified into the widespread moderate form chronic periodontitis (CP) and the rare early-onset and severe phenotype aggressive periodontitis (AgP). These different disease manifestations are thought to share risk alleles and predisposing environmental factors. To obtain novel insights into the shared genetic etiology and the underlying molecular mechanisms of both forms, we performed a two step-wise meta-analysis approach using genome-wide association studies of both phenotypes. Genotypes from imputed genome-wide association studies (GWAS) of AgP and CP comprising 5,095 cases and 9,908 controls of North-West European genetic background were included. Two loci were associated with periodontitis at a genome-wide significance level. They located within the pseudogene MTND1P5 on chromosome 8 (rs16870060-G, P = 3.69 × 10−9, OR = 1.36, 95% CI = [1.23–1.51]) and intronic of the long intergenic non-coding RNA LOC107984137 on chromosome 16, downstream of the gene SHISA9 (rs729876-T, P = 9.77 × 10−9, OR = 1.24, 95% CI = [1.15–1.34]). This study identified novel risk loci of periodontitis, adding to the genetic basis of AgP and CP.
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