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  1. Article ; Online: Shade is the most important factor limiting growth of a woody range expander.

    Ward, David

    PloS one

    2020  Volume 15, Issue 12, Page(s) e0242003

    Abstract: The expansion of woody plants into grasslands and old fields is often ascribed to fire suppression and heavy grazing, especially by domestic livestock. However, it is also recognized that nutrient availability and interspecific competition with grasses ... ...

    Abstract The expansion of woody plants into grasslands and old fields is often ascribed to fire suppression and heavy grazing, especially by domestic livestock. However, it is also recognized that nutrient availability and interspecific competition with grasses and other woody plants play a role in certain habitats. I examined potential factors causing range- and niche expansion by the eastern redcedar Juniperus virginiana, the most widespread conifer in the eastern United States, in multifactorial experiments in a greenhouse. Historical records suggest that the eastern redcedar is a pioneer forest species, and may be replaced as the forest increases in tree density due to shading. Another possible factor that affects its distribution may be nutrient availability, which is higher in old fields and other disturbed lands than in undisturbed habitats. In its historic range, eastern redcedars are particularly abundant on limestone outcrops, often termed 'cedar barrens'. However, the higher abundance on limestone could be due to reduced interspecific competition rather than a preference for high pH substrates. I manipulated shade, fertilization, lime, and interspecific competition with a common dominant tree, the post oak Quercus stellata. In a separate experiment, I manipulated fire and grass competition. I measured growth rates (height and diameter) and above- and belowground biomass at the end of both experiments. I also measured total non-structural carbohydrates and nitrogen in these plants. Shade was the most important factor limiting the growth rates and biomass of eastern redcedars. I also found that there were significant declines in nitrogen and non-structural carbohydrates when shaded. These results are consistent with the notion that the eastern redcedar is a pioneer forest species, and that shade is the reason that these redcedars are replaced by other tree species. In the second experiment, I found that a single fire had a negative effect on young trees. There was no significant effect of competition with grass, perhaps because the competitive effect was shading by grasses and not nutrient depletion. Overall, the effects of shade were far more apparent than the effects of fire.
    MeSH term(s) Biomass ; Ecosystem ; Fires ; Forests ; Grassland ; Juniperus/growth & development ; Juniperus/metabolism ; Nitrogen/metabolism ; Poaceae/growth & development ; Quercus/growth & development ; Quercus/metabolism ; Trees/growth & development ; Trees/metabolism ; United States
    Chemical Substances Nitrogen (N762921K75)
    Language English
    Publishing date 2020-12-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0242003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book: Stuttering and cluttering

    Ward, David

    frameworks for understanding and treatment

    2006  

    Author's details David Ward
    Keywords Stuttering ; Speech Disorders
    Language English
    Size XVII, 436 S. : Ill.
    Publisher Psychology Press
    Publishing place Hove u.a.
    Publishing country Great Britain
    Document type Book
    HBZ-ID HT014517018
    ISBN 1-84169-334-0 ; 978-1-84169-334-7
    Database Catalogue ZB MED Medicine, Health

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  3. Article: Eastern redcedar roots create legacy effects that suppresses growth of prairie species.

    Bennion, Leland D / Ward, David

    Ecology and evolution

    2023  Volume 13, Issue 12, Page(s) e10775

    Abstract: The expansion of woody species from their historical ranges into grasslands is a global problem. Understanding the mechanisms that enable species to successfully establish and then re-encroach following their removal is critical to effectively managing ... ...

    Abstract The expansion of woody species from their historical ranges into grasslands is a global problem. Understanding the mechanisms that enable species to successfully establish and then re-encroach following their removal is critical to effectively managing problem species. Legacy effects are a mechanism that could be critical to the reestablishment of woody encroachers following their removal. Legacy effects occur when a species alters the biotic and abiotic environment in a way that affects communities that establish subsequently. In this study, we assess whether the eastern redcedar (
    Language English
    Publishing date 2023-12-11
    Publishing country England
    Document type Journal Article
    ZDB-ID 2635675-2
    ISSN 2045-7758
    ISSN 2045-7758
    DOI 10.1002/ece3.10775
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Experimental drought suppresses grass productivity and passive warming promotes tree sapling performance: Insights from African savanna species

    Pillay, T. / Ward, D.

    Acta oecologica

    2022  Volume 114, Issue -, Page(s) 103813

    Document type Article
    ZDB-ID 1033625-4
    ISSN 1146-609X
    Database Current Contents Nutrition, Environment, Agriculture

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  5. Article ; Online: Trialling a convolution neural network for the identification of Braconidae in New Zealand

    Ward, Darren / Martin, Brent

    Journal of Hymenoptera Research. 2023 Feb. 17, v. 95 p.95-101

    2023  

    Abstract: AbstractComputer vision approaches, such as deep learning, potentially offer a range of benefits to entomology, particularly for the image-based identification of taxa. An experiment was conducted to gauge the ability of a convolution neural network ( ... ...

    Abstract AbstractComputer vision approaches, such as deep learning, potentially offer a range of benefits to entomology, particularly for the image-based identification of taxa. An experiment was conducted to gauge the ability of a convolution neural network (CNN) to identify genera of Braconidae from images of forewings. A deep learning CNN was trained via transfer learning from a small set of 488 images for 57 genera. Three-fold cross-validation achieved an accuracy of 96.7%, thus demonstrating that identification to genus using forewings is highly predictive. Further work is needed to increase both the coverage to species level and the number of images available.
    Keywords Braconidae ; entomology ; research ; vision ; New Zealand ; computer vision ; diagnositics ; identification ; model
    Language English
    Dates of publication 2023-0217
    Size p. 95-101.
    Publishing place Pensoft Publishers
    Document type Article ; Online
    ZDB-ID 2477175-2
    ISSN 1314-2607 ; 1070-9428
    ISSN (online) 1314-2607
    ISSN 1070-9428
    DOI 10.3897/jhr.95.95964
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: Plant-soil feedback from eastern redcedar (

    Bennion, Leland D / Ward, David

    Ecology and evolution

    2022  Volume 12, Issue 10, Page(s) e9400

    Abstract: The encroachment of woody plants into grasslands is an ongoing global problem that is largely attributed to anthropogenic factors such as climate change and land management practices. Determining the mechanisms that drive successful encroachment is a ... ...

    Abstract The encroachment of woody plants into grasslands is an ongoing global problem that is largely attributed to anthropogenic factors such as climate change and land management practices. Determining the mechanisms that drive successful encroachment is a critical step towards planning restoration and long-term management strategies. Feedbacks between soil and aboveground communities can have a large influence on the fitness of plants and must be considered as potentially important drivers for woody encroachment. We conducted a plant-soil feedback experiment in a greenhouse between eastern redcedar
    Language English
    Publishing date 2022-10-17
    Publishing country England
    Document type Journal Article
    ZDB-ID 2635675-2
    ISSN 2045-7758
    ISSN 2045-7758
    DOI 10.1002/ece3.9400
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Changes in white oak (

    Perkovich, Cynthia / Ward, David

    Ecology and evolution

    2022  Volume 12, Issue 4, Page(s) e8839

    Abstract: Periodical cicadas have mass emergences once every 13 or 17 years. Plants may need to upregulate defense production in response to an emergence. Defense production is energetically expensive, so plants may downregulate their production after periodical ... ...

    Abstract Periodical cicadas have mass emergences once every 13 or 17 years. Plants may need to upregulate defense production in response to an emergence. Defense production is energetically expensive, so plants may downregulate their production after periodical cicada populations dissipate. We examined the defensive responses in leaves, branches, and roots of a common host, white oak (
    Language English
    Publishing date 2022-04-25
    Publishing country England
    Document type Journal Article
    ZDB-ID 2635675-2
    ISSN 2045-7758
    ISSN 2045-7758
    DOI 10.1002/ece3.8839
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Telepractice application for the overt stuttering assessment of children aged 6-15 years old.

    Aldukair, Lamya / Ward, David

    International journal of language & communication disorders

    2022  Volume 57, Issue 5, Page(s) 1050–1070

    Abstract: Background: Despite the importance of delivering speech and language therapy services to children who stutter (CWS), there are barriers to accessing speech and language therapy. One way to improve access for those who may otherwise be deprived of speech ...

    Abstract Background: Despite the importance of delivering speech and language therapy services to children who stutter (CWS), there are barriers to accessing speech and language therapy. One way to improve access for those who may otherwise be deprived of speech and language therapy services, including CWS, is through telepractice (TP). However, there is currently no evidence as to the viability of TP stuttering assessments for CWS.
    Aim: To investigate the validity and reliability, and acceptability of using a TP application to assess overt stuttering behaviour children aged 6-15 years.
    Methods & procedure: A total of 30 CWS, aged between 6 and 15 years, were recruited from a speech therapy clinic in King Abdulaziz University Hospital in Riyadh, Saudi Arabia. Children were divided into two testing conditions, either face-to-face (f2f)-led or TP-led testing, and the Stuttering Severity Instrument (SSI-IV) was administered, percentage of syllables stuttered (%SS) was calculated, and severity ratings (SR) assigned, either via f2f or via TP using two laptops with webcams, video conference software and a broadband internet connection. Agreement and reliability of scoring in the two testing conditions were reported in addition to findings from questionnaires exploring children's and their caregivers' perceptions both before and immediately after the TP assessment was carried out.
    Outcome & results: A total of 30 sessions were successfully carried out, with results revealing unsatisfactory levels of agreement when applying the Bland and Altman method. However, when discrepancies were found, these were comparable with those from traditional f2f studies. Generally, parents and children exhibited high levels of satisfaction and held a positive view regarding TP pre- and post-assessment.
    Conclusions & implications: The results of the study suggest that conducting an overt stuttering assessment via TP for 6-15-year-olds CWS is reliable and valid. Although the TP model posed some (mainly technical) challenges for executing the assessment, high levels of satisfaction were recorded by parents and children alike. The TP system and equipment chosen in this study has provided a basis for the delivery of TP overt stuttering assessment in a clinical setting, thus addressing the barriers to access that are present for CWS. These results are preliminary, but they can be seen as a building block for future research in TP assessment studies for CWS.
    What this paper adds: What is already known on the subject Stuttering treatment via TP has been proven to be feasible and successful across a variety of treatment programs (e.g., Lidcombe, Camperdown). However, the viability of assessing stuttering via videoconferencing has never been explored in children. What this paper adds to existing knowledge Preliminary support for the assessment of overt stuttering in CWS aged 6-15 years via video conferencing. The results justify larger scale studies of this service delivery method. What are the potential or actual clinical implications of this work? The TP system and equipment chosen in this study has provided a basis for the delivery of TP overt stuttering assessment in a clinical setting, thus addressing the barriers to access that are present for CWS aged 6-15 years.
    MeSH term(s) Adolescent ; Child ; Child Behavior ; Humans ; Parents ; Reproducibility of Results ; Speech ; Speech Therapy/methods ; Stuttering/diagnosis ; Stuttering/therapy
    Language English
    Publishing date 2022-06-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1415919-3
    ISSN 1460-6984 ; 1368-2822
    ISSN (online) 1460-6984
    ISSN 1368-2822
    DOI 10.1111/1460-6984.12739
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Using Small Grants to SPARK! Substantial Reach to Reduce HIV-related Stigma.

    Reif, Susan / Wilson, Elena / Cooper, Haley / Beckwith, Nicole / Ward, Dafina

    Journal of health care for the poor and underserved

    2024  Volume 34, Issue 3S, Page(s) 69–76

    Abstract: Community-based organizations (CBOs) are well-positioned to address the negative effects of HIV stigma, which is prevalent in the U.S. South. This article describes a Gilead COMPASS-funded small grants and capacity-building program for CBOs to address ... ...

    Abstract Community-based organizations (CBOs) are well-positioned to address the negative effects of HIV stigma, which is prevalent in the U.S. South. This article describes a Gilead COMPASS-funded small grants and capacity-building program for CBOs to address stigma and describes the broad reach and positive outcomes associated with program implementation.
    MeSH term(s) Humans ; HIV Infections/prevention & control ; Social Stigma ; Financing, Organized ; Capacity Building ; Female ; Male ; Adult ; Community Health Services/organization & administration
    Language English
    Publishing date 2024-04-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1142637-8
    ISSN 1548-6869 ; 1049-2089
    ISSN (online) 1548-6869
    ISSN 1049-2089
    DOI 10.1353/hpu.2023.a903353
    Database MEDical Literature Analysis and Retrieval System OnLINE

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