354 research outputs found

    Invasive Andropogon gayanus (gamba grass) is an ecosystem transformer of nitrogen relations in Australian savanna

    Get PDF
    The African grass Andropogon gayanus Kunth. is invading Australian savannas, altering their ecological and biogeochemical function. To assess impacts on nitrogen (N) cycling, we quantified litter decomposition and N dynamics of grass litter in native grass and A. gayanus invaded savanna using destructive in situ grass litter harvests and litterbag incubations (soil surface and aerial position). Only 30% of the A. gayanus in situ litter decomposed, compared to 61% of the native grass litter, due to the former being largely comprised of highly resistant A. gayanus stem. In contrast to the stem, A. gayanus leaf decomposition was approximately 3- and 2-times higher than the dominant native grass, Alloteropsis semilata at the surface and aerial position, respectively. Lower initial lignin concentrations, and higher consumption by termites, accounted for the greater surface decomposition rate of A. gayanus. N flux estimates suggest the N release of A. gayanus litter is insufficient to compensate for increased N uptake and N loss via fire in invaded plots. Annually burnt invaded savanna may lose up to 8.2% of the upper soil N pool over a decade. Without additional inputs via biological N fixation, A. gayanus invasion is likely to diminish the N capital of Australia's frequently burnt savannas

    Optimal stomatal behaviour around the world

    Get PDF
    This is the author accepted manuscript. The final version is available from Springer Nature via the DOI in this recordStomatal conductance (g s) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of g s in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of g s that allow predictions of stomatal behaviour are lacking. Here, we present a database of globally distributed g s obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model and the leaf and wood economics spectrum. We also demonstrate a global relationship with climate. These findings provide a robust theoretical framework for understanding and predicting the behaviour of g s across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.This research was supported by the Australian Research Council (ARC MIA Discovery Project 1433500-2012-14). A.R. was financially supported in part by The Next-Generation Ecosystem Experiments (NGEE-Arctic) project, which is supported by the Office of Biological and Environmental Research in the Department of Energy, Office of Science, and through the United States Department of Energy contract No. DE-AC02-98CH10886 to Brookhaven National Laboratory. M.O.d.B. acknowledges that the Brassica data were obtained within a research project financed by the Belgian Science Policy (OFFQ, contract number SD/AF/02) and coordinated by K. Vandermeiren at the Open-Top Chamber research facilities of CODA-CERVA (Tervuren, Belgium)

    Optimal stomatal behaviour around the world

    Get PDF
    © 2015 Macmillan Publishers Limited. All rights reserved. Stomatal conductance (g s) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of g s in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of g s that allow predictions of stomatal behaviour are lacking. Here, we present a database of globally distributed g s obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model and the leaf and wood economics spectrum. We also demonstrate a global relationship with climate. These findings provide a robust theoretical framework for understanding and predicting the behaviour of g s across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate

    World Workshop on Oral Medicine VII : Immunobiologics for salivary gland disease in Sjögren's syndrome : a systematic review

    Get PDF
    Objective: This systematic review evaluated the efficacy of immunobiologics for the management of oral disease in Sj\uf6gren's syndrome (SS). Materials and Methods: MEDLINE\uae, Embase, Scopus, and the Cochrane Library were searched for evidence on the use of immunobiologics for management of glandular disease in SS. Primary outcomes were xerostomia and salivary gland dysfunction, assessed via visual analogue scales, disease-specific scales for SS, measurement of salivary flow, ultrasound data, and quality of life measures. Results: Seventeen studies (11 randomized controlled trials and 6 observational studies) met inclusion criteria. Rituximab showed efficacy in improving salivary gland function but not xerostomia. Abatacept showed promise in improving both xerostomia and salivary flow. Belimumab exhibited long-term improvement of salivary flow and subjective measures. The novel agent CFZ533 improved both disease activity and patient-reported indexes. Conclusions: There is strong evidence pointing to the efficacy of rituximab in the management of oral disease in SS. Future controlled trials may elucidate the efficacy of belimumab and abatacept. The new drug CFZ533 is a promising alternative for the management of SS and its salivary gland involvement. In considering these agents, the promise of efficacy must be balanced against the harmful effects associated with biologic agents

    Validation of an Oral Disease Severity Score (ODSS) tool for use in oral mucous membrane pemphigoid

    Get PDF
    Background: Mucous membrane pemphigoid (MMP) is a rare autoimmune bullous disease predominantly affecting the oral mucosa. Optimal management relies upon thorough clinical assessment and documentation at each visit. Objectives: The primary aim of this study was to validate the Oral Disease Severity Score (ODSS) for the assessment of oral involvement in MMP. We also compared its inter- and intraobserver reliability with those of the oral parts of the Mucous Membrane Pemphigoid Disease Area Index (MMPDAI), Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and Physician's Global Assessment (PGA). Methods: Fifteen patients with mild-to-moderately severe oral MMP were scored for disease severity by 10 oral medicine clinicians from four U.K. centres using the ODSS, the oral sections of MMPDAI and ABSIS, and PGA. Two clinicians rescored all patients after 2 h. Results: In terms of reliability, the interobserver ODSS total score intraclass correlation coefficient (ICC) was 0·97, MMPDAI activity 0·59 and damage 0·15, ABSIS total 0·84, and PGA 0·72. The intraobserver ICCs (two observers) for ODSS total were 0·97 and 0·93; for MMPDAI activity 0·93 and 0·70 and damage 0·93 and 0·79; for ABSIS total 0·99 and 0·94; and for PGA 0·92 and 0·94. Convergent validity between ODSS and MMPDAI was good (correlation coefficient 0·88). The mean ± SD time for completion of ODSS was 93 ± 31 s, with MMPDAI 102 ± 24 s and ABSIS involvement 71 ± 18 s. The PGA took &lt; 5 s. Conclusions: This study has validated the ODSS for the assessment of oral MMP. It has shown superior interobserver agreement over MMPDAI, ABSIS and PGA, and superior intraobserver reliability to MMPDAI. It is quick and easy to perform. What's already known about this topic?. There are no validated scoring methodologies for oral mucous membrane pemphigoid (MMP). Proposed disease activity scoring tools for MMP include the Mucous Membrane Disease Area Index (MMPDAI) and the Autoimmune Bullous Skin Disorder Intensity Score (ABSIS). The Oral Disease Severity Score (ODSS) has been validated for use in oral pemphigus vulgaris (PV). It has been shown to be reliable and sensitive in both lichen planus (LP) and MMP. What does this study add?. The ODSS has been shown to be a thorough, sensitive and reproducible, yet quick scoring tool for the assessment of oral involvement in MMP. Its versatility for use in oral PV, MMP and LP is an added advantage over other scoring methodologies. What are the clinical implications of this work?. We propose that the ODSS be used as a clinical scoring tool for monitoring activity in oral MMP in clinical practice as well as for use in multicentre studies.</p

    World Workshop on Oral Medicine VIII: Development of a core outcome set for oral lichen planus: a systematic review of outcome domains

    Get PDF
    Objective: There is a lack of consensus regarding clinician- and patient-reported oral lichen planus (OLP) outcomes. The World Workshop on Oral Medicine Outcomes Initiative for the Direction of Research (WONDER) Project aims to develop a core outcome set (COS) for OLP, which would inform the design of clinical trials and, importantly, facilitate meta-analysis, leading to the establishment of more robust evidence for the management of this condition and hence improved patient care. Study Design: Ovid MEDLINE, Embase, CINAHL, CENTRAL, and Clinicaltrials.gov were searched for interventional studies (randomized controlled trials, controlled clinical trials, and case series including ≥5 participants) on OLP and oral lichenoid reactions published between January 2001 and March 2022 without language restriction. All reported primary and secondary outcomes were extracted. Results: The searches yielded 9,135 records, and 291 studies were included after applying the inclusion criteria. A total of 422 outcomes were identified. These were then grouped based on semantic similarity, condensing the list to 69 outcomes. The most frequently measured outcomes were pain (51.9%), clinical grading of the lesions (29.6%), lesion size/extension/area (27.5%), and adverse events (17.5%). Conclusion: As a first step in developing a COS for OLP, we summarized the outcomes that have been used in interventional studies over the past 2 decades, which are numerous and heterogeneous.S

    World Workshop on Oral Medicine VIII: Development of a core outcome set for oral lichen planus: the patient perspective

    Get PDF
    Objective: This study aimed to explore the lived experience of patients with oral lichen planus (OLP) and investigate what treatment-related outcomes are the most important to them and should be included in a core outcome set (COS) for OLP. Study Design: A qualitative study involving focus group work with 10 participants was conducted. Interviews with each focus group were held twice: session 1 explored the lived experience of patients with OLP, and session 2 allowed patients to review a summary of the outcome domains used in the OLP literature to date. The discussions were recorded, transcribed verbatim, and analyzed using framework analysis. Results: In session 1, 4 themes and 8 sub-themes emerged from the data analysis. An additional outcome, ‘knowledge of family and friends,’ was suggested in session 2. Conclusions: We have gained valuable insight into the lived experience of patients with OLP via this qualitative study. To our knowledge, this study is the first to explore the patient perspective on what should be measured in clinical trials on OLP, highlighting an important additional suggested outcome. This additional outcome will be voted upon in a consensus process to determine a minimum COS for OLPS

    The challenge of rural life nostalgia: barriers in redevelopment of Malay Reserve Land (MRL) in Klang Valley

    Get PDF
    The development of Malay reserve land is a nationwide issue which can be overcome through better understanding of the existing barriers. While many barriers have been examined, the challenges relating to land owner expectations and preferences has not been thoroughly examined. Using Kg Sungai Penchala in the capital city Kuala Lumpur as a case, this research used a structured interview survey of 258 respondents representing both owners and tenants. Statistical analysis demonstrates that majority of the land owners (individuals) rejected the idea to further develop the land. The land owners preferred to maintain the village status quo and they were satisfied with the current development level in the village. Only a minority of respondents agreed that the land should be developed and instead perceived that re-development of this Malay Reserve Land of Kg Sungai Penchala would be able to raise their quality of life. The restriction is much preferred by the land owners who preferred the current style of village living. Thus, immediate re-development of the area is not warranted and the preference of the land owners represents a strong barrier
    corecore