Using yield maps and intensive soil sampling to improve nitrogen fertiliser recommendations from a deterministic model in the Western Australian wheatbelt

2000 ◽  
Vol 40 (7) ◽  
pp. 959 ◽  
Author(s):  
M. L. Adams ◽  
S. Cook ◽  
J. W. Bowden

A field-scale experiment was conducted to determine the ability of a deterministic model developed for Western Australian wheat farmers to guide site-specific applications of nitrogen fertiliser. The results indicated that site-specific information of achievable yield improved the prediction accuracy much more than information about soil nitrogen — even though the latter was more costly to acquire. When applied together, these sources of information improved the prediction accuracy of the model markedly, explaining about half of the variation of yield response to nitrogen. However, the model failed to explain a substantial portion of site-specific variation, even with this intensity of information. This failure indicates the difficulty of representing complex biological systems with simple functional models.

2021 ◽  
Vol 11 (2) ◽  
pp. 177
Author(s):  
Mihye Choi ◽  
Mohinish Shukla

Speech is an acoustically variable signal, and one of the sources of this variation is the presence of multiple speakers. Empirical evidence has suggested that adult listeners possess remarkably sensitive (and systematic) abilities to process speech signals, despite speaker variability. It includes not only a sensitivity to speaker-specific variation, but also an ability to utilize speaker variation with other sources of information for further processing. Recently, many studies also showed that young children seem to possess a similar capacity. This suggests continuity in the processing of speaker-dependent speech variability, and suggests that this ability could also be important for infants learning their native language. In the present paper, we review evidence for speaker variability and speech processing in adults, and speaker variability and speech processing in young children, with an emphasis on how they make use of speaker-specific information in word learning situations. Finally, we will build on these findings to make a novel proposal for the use of speaker-specific information processing in phoneme learning in infancy.


2020 ◽  
Vol 10 (12) ◽  
pp. 4599-4613
Author(s):  
Fabio Morgante ◽  
Wen Huang ◽  
Peter Sørensen ◽  
Christian Maltecca ◽  
Trudy F. C. Mackay

The ability to accurately predict complex trait phenotypes from genetic and genomic data are critical for the implementation of personalized medicine and precision agriculture; however, prediction accuracy for most complex traits is currently low. Here, we used data on whole genome sequences, deep RNA sequencing, and high quality phenotypes for three quantitative traits in the ∼200 inbred lines of the Drosophila melanogaster Genetic Reference Panel (DGRP) to compare the prediction accuracies of gene expression and genotypes for three complex traits. We found that expression levels (r = 0.28 and 0.38, for females and males, respectively) provided higher prediction accuracy than genotypes (r = 0.07 and 0.15, for females and males, respectively) for starvation resistance, similar prediction accuracy for chill coma recovery (null for both models and sexes), and lower prediction accuracy for startle response (r = 0.15 and 0.14 for female and male genotypes, respectively; and r = 0.12 and 0.11, for females and male transcripts, respectively). Models including both genotype and expression levels did not outperform the best single component model. However, accuracy increased considerably for all the three traits when we included gene ontology (GO) category as an additional layer of information for both genomic variants and transcripts. We found strongly predictive GO terms for each of the three traits, some of which had a clear plausible biological interpretation. For example, for starvation resistance in females, GO:0033500 (r = 0.39 for transcripts) and GO:0032870 (r = 0.40 for transcripts), have been implicated in carbohydrate homeostasis and cellular response to hormone stimulus (including the insulin receptor signaling pathway), respectively. In summary, this study shows that integrating different sources of information improved prediction accuracy and helped elucidate the genetic architecture of three Drosophila complex phenotypes.


2008 ◽  
Vol 3 (3) ◽  
pp. 57 ◽  
Author(s):  
Carol Perryman

A Review of: Brown, Cecilia M. and Ortega, Lina. “Information-Seeking Behavior of Physical Science Librarians: Does Research Inform Practice?” College & Research Libraries (2005). 66:231-47. Objective – As part of a larger study exploring the information environments of physical science librarians (Ortega & Brown), the authors’ overall objective for this study is to profile physical science librarians’ information behaviours. The authors’ two-part hypothesis was that first, peer-reviewed journals would be preferred over all other sources for research dissemination, resembling the preferences of scientists, and second, that peer-to-peer consultation would predominate for practice-oriented decisions. Design – Mixed methods: survey questionnaire followed by citation and content analysis. Setting – Five internationally disseminated professional association electronic mailing lists whose readership comprised those with interests in science librarianship: the American Library Association (ALA) Science and Technology Section; the American Society for Information Science & Technology (ASIST) Science and Technology Information Special Interest Group; the Special Library Association (SLA) Chemistry Division and its Physics-Astronomy-Mathematics Division; and the American Geological Institute Geoscience Information Society. Subjects – Seventy-two physical science librarians voluntarily responding to an online survey. Methods – A questionnaire was distributed to inquire about physical science librarians’ professional reading practices as well as their perceptions about the applicability of research to their work. Participants were asked to rank preferences among 11 resource types as sources supporting daily business, including personal communication, conference attendance, electronic mailing lists, and scholarly journals. Differences between the mean rankings of preferences were tested for significance by applying the Friedman test with p>0.0005. Journals identified most frequently were analyzed using the Institute for Scientific Information’s (ISI) Web of Science index and Ulrich’s Periodical Index to measure proportions of research and non-research citations, as well as the general topic areas covered by the journals. Next, content analysis was performed for the years 1995, 1997, and 2000 in order to characterize research methodologies used in the previously identified journals according to a previously tested schema (Buscha & Harter). Results from this portion of the study were compared with participants’ responses about journal usage. Main Results – Librarians reported using personal communication (both face-to-face and electronic mailing lists) more frequently as a means of information gathering than professional journals, Web sites, conferences, trade publications, monographs, or ‘other’ resources. Variations in responses appeared to correlate with years in the profession and in the respondents’ time in their current positions, although there are indications that the importance of all information resources to practice and research declines over time. The relative importance of resources is also shown in time spent reading journal literature, less than 5 hours per week for 86% of participants. Conclusion – For the first hypothesis, the authors found that unlike scientists, survey participants did not prefer research publications as vehicles for dissemination of their research results. For the second, librarians ranked peer-reviewed journals third in preference after personal communication and electronic mailing lists as sources of information supporting daily practice, supporting the second hypothesis that respondents would emulate the information use practices of mathematicians.


2006 ◽  
Vol 2 (2) ◽  
pp. 213-216 ◽  
Author(s):  
Sylvia M Fallon ◽  
Robert C Fleischer ◽  
Gary R Graves

We tested the hypothesis that malarial parasites ( Plasmodium and Haemoproteus ) of black-throated blue warblers ( Dendroica caerulescens ) provide sufficient geographical signal to track population movements between the warbler's breeding and wintering habitats in North America. Our results from 1083 warblers sampled across the species' breeding range indicate that parasite lineages are geographically widespread and do not provide site-specific information. The wide distribution of malarial parasites probably reflects postnatal dispersal of their hosts as well as mixing of breeding populations on the wintering range. When compared to geographically structured parasites of sedentary Caribbean songbirds, patterns of malarial infections in black-throated blue warblers suggest that host–malaria dynamics of migratory and sedentary bird populations may be subject to contrasting selection pressures.


Author(s):  
Jorge Mendoza Espinosa ◽  
Jochen Köhler

<p>Monopiles are the most common offshore wind turbine support structures. They are to be designed so that resonance with the rotor-passing excitation is avoided. However, the estimation of the eigenfrequencies is strongly influenced by the soil-structure interaction, whose characterization with prior information is associated with large uncertainties. No clear guideline is given regarding the safety margin to be left between the structure first natural frequency and the excitation regions. In this paper, the expected consequences of leaving a certain margin are studied and quantified. The decisions regarding the investment in site-specific characterization are coupled into the decision scenario by means of a value of information analysis. The results provide insight on the efficient allocation of resources at the design point in time and the sensitivity of the decisions regarding the probabilistic characterization of the design scenario.</p>


Author(s):  
Nina Manzke ◽  
Martin Kada ◽  
Thomas Kastler ◽  
Shaojuan Xu ◽  
Norbert de Lange ◽  
...  

Urban sprawl and the related landscape fragmentation is a Europe-wide challenge in the context of sustainable urban planning. The URBan land recycling Information services for Sustainable cities (URBIS) project aims for the development, implementation, and validation of web-based information services for urban vacant land in European functional urban areas in order to provide end-users with site specific characteristics and to facilitate the identification and evaluation of potential development areas. The URBIS services are developed based on open geospatial data. In particular, the Copernicus Urban Atlas thematic layers serve as the main data source for an initial inventory of sites. In combination with remotely sensed data like SPOT5 images and ancillary datasets like OpenStreetMap, detailed site specific information is extracted. Services are defined for three main categories: i) baseline services, which comprise an initial inventory and typology of urban land, ii) update services, which provide a regular inventory update as well as an analysis of urban land use dynamics and changes, and iii) thematic services, which deliver specific information tailored to end-users' needs.


2009 ◽  
Vol 9 (2) ◽  
pp. 127-132 ◽  
Author(s):  
Gertjan Medema ◽  
Patrick Smeets

System assessment is the part of the Water Safety Plan that evaluates whether a water supply system is capable of producing drinking water that meets the health-based targets. System assessment can be done at increasing level of detail, requiring more site specific information as the level of detail increases. Four case studies are presented with increasing level of detail, showing the type of information that is required for each of these levels and how each level informs risk management. The first case study shows how a system assessment can be performed without other site specific information than the type of source water and the type of treatment processes. The required data for the system assessment are collected from the large body of literature available. The second case study uses site specific microbial indicator data. The third study uses pathogen data and the fourth case study combines data on pathogens, microbial indicators and process parameters. The case studies show that the level of detail required largely depends on the risk management question.


2007 ◽  
Vol 143 (8) ◽  
Author(s):  
Lily Changchien ◽  
Stephen W. Dusza ◽  
Anna Liza Chan Agero ◽  
Adam J. Korzenko ◽  
Ralph P. Braun ◽  
...  

2018 ◽  
Vol 110 (4) ◽  
pp. 1544-1553 ◽  
Author(s):  
Tomás Coyos ◽  
Lucas Borrás ◽  
Brenda L. Gambin

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1854
Author(s):  
Humna Khan ◽  
Aitazaz A. Farooque ◽  
Bishnu Acharya ◽  
Farhat Abbas ◽  
Travis J. Esau ◽  
...  

The delineation of management zones (MZs) has been suggested as a solution to mitigate adverse impacts of soil variability on potato tuber yield. This study quantified the spatial patterns of variability in soil and crop properties to delineate MZs for site-specific soil fertility characterization of potato fields through proximal sensing of fields. Grid sampling strategy was adopted to collect soil and crop data from two potato fields in Prince Edward Island (PEI). DUALEM-2 sensor, Time Domain Reflectometry (TDR-300), GreenSeeker were used to collect soil ground conductivity parameter horizontal coplanar geometry (HCP), soil moisture content (θ), and normalized difference vegetative index (NDVI), respectively. Soil organic matter (SOM), soil pH, phosphorous (P), potash (K), iron (Fe), lime index (LI), and cation exchange capacity (CEC) were determined from soil samples collected from each grid. Stepwise regression shortlisted the major properties of soil and crop that explained 71 to 86% of within-field variability. The cluster analysis grouped the soil and crop data into three zones, termed as excellent, medium, and poor at a 40% similarity level. The coefficient of variation and the interpolated maps characterized least to moderate variability of soil fertility parameters, except for HCP and K that were highly variable. The results of multiple means comparison indicated that the tuber yield and HCP were significantly different in all MZs. The significant relationship between HCP and yield suggested that the ground conductivity data could be used to develop MZs for site-specific fertilization in potato fields similar to those used in this study.


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