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1.
Glob Chang Biol ; 30(1): e17053, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273544

RESUMEN

Soil is a huge carbon (C) reservoir, but where and how much extra C can be stored is unknown. Current methods to estimate the maximum amount of mineral-associated organic carbon (MAOC) stabilized in the fine fraction (clay + silt, < 20 µm $$ <20\;\upmu \mathrm{m} $$ ) fit through the MAOC versus clay + silt relationship, not their maxima, making their estimates more uncertain and unreliable. We need a function that 'envelopes' that relationship. Here, using 5089 observations, we estimated that the uppermost 30 cm of Australian soil holds 13 Gt (10-18 Gt) of MAOC. We then fitted frontier lines, by soil type, to the relationship between MAOC and the percentage of clay + silt to estimate the maximum amounts of MAOC that Australian soils could store in their current environments, and calculated the MAOC deficit, or C sequestration potential. We propagated the uncertainties from the frontier line fitting and mapped the estimates of these values over Australia using machine learning and kriging with external drift. The maps show regions where the soil is more in MAOC deficit and has greater sequestration potential. The modelling shows that the variation over the whole continent is determined mainly by climate, linked to vegetation and soil mineralogy. We find that the MAOC deficit in Australian soil is 40 Gt (25-60 Gt). The deficit in the vast rangelands is 20.84 Gt (13.97-29.70 Gt) and the deficit in cropping soil is 1.63 Gt (1.12-2.32 Gt). Management could increase C sequestration in these regions if the climate allowed it. Our findings provide new information on the C sequestration potential of Australian soils and highlight priority regions for soil management. Australia could benefit environmentally, socially and economically by unlocking even a tiny portion of its soil's C sequestration potential.


Asunto(s)
Carbono , Suelo , Arcilla , Carbono/análisis , Secuestro de Carbono , Australia , Minerales
2.
Phys Rev Lett ; 130(9): 091801, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36930908

RESUMEN

The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ.

3.
J Evol Biol ; 30(9): 1674-1691, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28714217

RESUMEN

The mechanism of pollinator attraction is predicted to strongly influence both plant diversification and the extent of pollinator sharing between species. Sexually deceptive orchids rely on mimicry of species-specific sex pheromones to attract their insect pollinators. Given that sex pheromones tend to be conserved among related species, we predicted that in sexually deceptive orchids, (i) pollinator sharing is rare, (ii) closely related orchids use closely related pollinators and (iii) there is strong bias in the wasp lineages exploited by orchids. We focused on species that are pollinated by sexual deception of thynnine wasps in the distantly related genera Caladenia and Drakaea, including new field observations for 45 species of Caladenia. Specialization was extreme with most orchids using a single pollinator species. Unexpectedly, seven cases of pollinator sharing were found, including two between Caladenia and Drakaea, which exhibit strikingly different floral morphology. Phylogenetic analysis of pollinators using four nuclear sequence loci demonstrated that although orchids within major clades primarily use closely related pollinator species, up to 17% of orchids within these clades are pollinated by a member of a phylogenetically distant wasp genus. Further, compared to the total diversity of thynnine wasps within the study region, orchids show a strong bias towards exploiting certain genera. Although these patterns may arise through conservatism in the chemical classes used in sex pheromones, apparent switches between wasp clades suggest unexpected flexibility in floral semiochemical production. Alternatively, wasp sex pheromones within lineages may exhibit greater chemical diversity than currently appreciated.


Asunto(s)
Evolución Biológica , Orchidaceae , Filogenia , Polinización , Animales , Flores , Avispas
4.
J Public Health (Oxf) ; 39(4): e235-e241, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27642124

RESUMEN

Background: Compared to the general population, the Traveller community has substantial health inequalities. Vaccination coverage in Traveller children is estimated to be low and Travellers are at higher risk of vaccine-preventable diseases due to their social circumstances. Methods: Audit of vaccination history of Traveller (n = 214) and non-Traveller (n = 776) children registered at a general practice in England. The Green Book childhood immunization schedule was used as a reference standard. Results: There was significantly lower coverage for Traveller children compared to non-Traveller children for all vaccinations in the routine childhood immunization schedule. The percentage of children completing the schedule at all time points was significantly lower in the Traveller community. Conclusions: Traveller communities have significantly lower uptake of vaccinations, and therefore Travellers' children should be targeted by general practitioners for catch-up vaccination to improve outcomes for individuals and local herd immunity.


Asunto(s)
Romaní/estadística & datos numéricos , Cobertura de Vacunación/estadística & datos numéricos , Adolescente , Niño , Preescolar , Disparidades en Atención de Salud , Humanos , Lactante , Recién Nacido , Irlanda/epidemiología , Auditoría Médica , Vacunación/estadística & datos numéricos
5.
Allergy ; 70(1): 80-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25331546

RESUMEN

BACKGROUND: Alveolar macrophages are sentinels of the pulmonary mucosa and central to maintaining immunological homeostasis. However, their role in governing the response to allergen is not fully understood. Inappropriate responses to the inhaled environment manifest as asthma. METHODS: We utilized a mechanistic IL-13-driven model and a house dust mite allergen mucosal sensitization model of allergic airway disease to investigate the role of alveolar macrophages in regulating pulmonary inflammation. RESULTS: IL-13-dependent eosinophilic and Th2 inflammation was enhanced in mice depleted of alveolar macrophages using clodronate liposomes. Similarly, depletion of alveolar macrophages during house dust mite sensitization or established disease resulted in augmented Th2 immunity and increased allergen-specific IgG1 and IgE. Clodronate treatment also delayed the resolution of tissue inflammation following cessation of allergen challenge. Strikingly, tissue interstitial macrophages were elevated in alveolar macrophage-deficient mice identifying a new homeostatic relationship between different macrophage subtypes. A novel role for the macrophage-derived immunoregulatory cytokine IL-27 was identified in modulating Th2 inflammation following mucosal allergen exposure. CONCLUSIONS: In summary, alveolar macrophages are critical regulators of Th2 immunity and their dysregulation promotes an inflammatory environment with exacerbation of allergen-induced airway pathology. Manipulating IL-27 may provide a novel therapeutic strategy for the treatment of asthma.


Asunto(s)
Alérgenos/inmunología , Homeostasis , Pulmón/inmunología , Macrófagos Alveolares/inmunología , Animales , Antígenos Dermatofagoides/inmunología , Asma/inmunología , Asma/metabolismo , Asma/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Interleucina-13/metabolismo , Interleucina-13/farmacología , Interleucina-27/metabolismo , Leucocitos/inmunología , Leucocitos/metabolismo , Pulmón/metabolismo , Pulmón/patología , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Ratones , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/patología , Células Th2/inmunología , Células Th2/metabolismo
6.
J Evol Biol ; 28(3): 601-12, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25619237

RESUMEN

Plants are predicted to show floral adaptation to geographic variation in the most effective pollinator, potentially leading to reproductive isolation and genetic divergence. Many sexually deceptive orchids attract just a single pollinator species, limiting opportunities to experimentally investigate pollinator switching. Here, we investigate Drakaea concolor, which attracts two pollinator species. Using pollinator choice tests, we detected two morphologically similar ecotypes within D. concolor. The common ecotype only attracted Zaspilothynnus gilesi, whereas the rare ecotype also attracted an undescribed species of Pogonothynnus. The rare ecotype occurred at populations nested within the distribution of the common ecotype, with no evidence of ecotypes occurring sympatrically. Surveying for pollinators at over 100 sites revealed that ecotype identity was not correlated with wasp availability, with most orchid populations only attracting the rare Z. gilesi. Using microsatellite markers, genetic differentiation among populations was very low (GST = 0.011) regardless of ecotype, suggestive of frequent gene flow. Taken together, these results may indicate that the ability to attract Pogonothynnus has evolved recently, but this ecotype is yet to spread. The nested distribution of ecotypes, rather than the more typical formation of ecotypes in allopatry, illustrates that in sexually deceptive orchids, pollinator switching could occur throughout a species' range, resulting from multiple potentially suitable but unexploited pollinators occurring in sympatry. This unusual case of sympatric pollinators highlights D. concolor as a promising study system for further understanding the process of pollinator switching from ecological, chemical and genetic perspectives.


Asunto(s)
Orchidaceae/fisiología , Polinización , Avispas/fisiología , Animales , Evolución Biológica , Tamaño Corporal , Ecotipo , Flores , Flujo Génico , Genética de Población , Repeticiones de Microsatélite , Orchidaceae/genética , Simpatría , Avispas/anatomía & histología , Australia Occidental
7.
Int J Obes (Lond) ; 38(1): 11-5, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24077005

RESUMEN

This review seeks to provide a current overview of musculoskeletal pain in overweight and obese children. Databases searched were Academic Search Complete, CINAHL, Medline, Proquest Health and Medical Complete, Scopus, Google Scholar, SPORTDiscuss and Trove for studies published between 1 January 2000 and 30 December 2012. We used a broad definition of children within a 3- to 18-year age range. The search strategy included the following terms: obesity, morbid obesity, overweight, pain, musculoskeletal pain, child, adolescent, chronic pain, back pain, lower back pain, knee pain, hip pain, foot pain and pelvic pain. Two authors independently assessed each record, and any disagreement was resolved by the third author. Data were analysed using a narrative thematic approach owing to the heterogeneity of reported outcome measures. Ninety-seven records were initially identified using a variety of terms associated with children, obesity and musculoskeletal pain. Ten studies were included for thematic analysis when predetermined inclusion criteria were applied. Bone deformity and dysfunction, pain reporting and the impact of children being overweight or obese on physical activity, exercise and quality of life were the three themes identified from the literature. Chronic pain, obesity and a reduction in physical functioning and activity may contribute to a cycle of weight gain that affects a child's quality of life. Future studies are required to examine the sequela of overweight and obese children experiencing chronic musculoskeletal pain.


Asunto(s)
Actividad Motora , Dolor Musculoesquelético/epidemiología , Dolor Musculoesquelético/etiología , Obesidad Infantil/complicaciones , Obesidad Infantil/epidemiología , Calidad de Vida , Actividades Cotidianas , Adolescente , Niño , Preescolar , Dieta , Femenino , Humanos , Masculino , Dolor Musculoesquelético/prevención & control , Obesidad Infantil/prevención & control
8.
Br J Cancer ; 108(2): 409-19, 2013 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-23287991

RESUMEN

BACKGROUND: Effective treatment of prostate cancer should be based on targeting interactions between tumour cell signalling pathways and key converging downstream effectors. Here, we determined how the tumourigenic phosphoinositide 3-kinase/protein kinase B (PI3K/AKT), tumour-suppressive phosphatase and tensin homologue deleted on chromosome 10 (PTEN) and transforming growth factor-ß (TGF-ß) pathways are integrated via the metastasis suppressor, N-myc downstream-regulated gene-1 (NDRG1). Moreover, we assessed how the novel anti-tumour agent, Dp44mT, may target these integrated pathways by increasing NDRG1 expression. METHODS: Protein expression in Dp44mT-treated normal human prostate epithelial cells and prostate cancer cells (PC-3, DU145) was assessed by western blotting. The role of NDRG1 was examined by transfection using an NDRG1 overexpression vector or shRNA. RESULTS: Dp44mT increased levels of tumour-suppressive PTEN, and decreased phosphorylation of ERK1/2 and SMAD2L, which are regulated by oncogenic Ras/MAPK signalling. Importantly, the effects of Dp44mT on NDRG1 and p-SMAD2L expression were more marked in prostate cancer cells than normal prostate epithelial cells. This may partly explain the anti-tumour selectivity of these agents. Silencing NDRG1 expression increased phosphorylation of tumourigenic AKT, ERK1/2 and SMAD2L and decreased PTEN levels, whereas NDRG1 overexpression induced the opposite effect. Furthermore, NDRG1 silencing significantly reduced the ability of Dp44mT to suppress p-SMAD2L and p-ERK1/2 levels. CONCLUSION: NDRG1 has an important role in mediating the tumour-suppressive effects of Dp44mT in prostate cancer via selective targeting of the PI3K/AKT, TGF-ß and ERK pathways.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Células Epiteliales/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Tiosemicarbazonas/farmacología , Antineoplásicos/farmacología , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Masculino , Fosfohidrolasa PTEN/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Próstata/citología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , ARN Interferente Pequeño , Transducción de Señal , Proteína Smad2/metabolismo , Factor de Crecimiento Transformador beta/metabolismo
9.
Nat Genet ; 24(2): 171-4, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10655064

RESUMEN

Smad proteins are intracellular mediators of signalling initiated by Tgf-betasuperfamily ligands (Tgf-betas, activins and bone morphogenetic proteins (Bmps)). Smads 1, 2, 3, 5 and 8 are activated upon phosphorylation by specific type I receptors, and associate with the common partner Smad4 to trigger transcriptional responses. The inhibitory Smads (6 and 7) are transcriptionally induced in cultured cells treated with Tgf-beta superfamily ligands, and downregulate signalling in in vitro assays. Gene disruption in mice has begun to reveal specific developmental and physiological functions of the signal-transducing Smads. Here we explore the role of an inhibitory Smad in vivo by targeted mutation of Madh6 (which encodes the Smad6 protein). Targeted insertion of a LacZ reporter demonstrated that Smad6 expression is largely restricted to the heart and blood vessels, and that Madh6 mutants have multiple cardiovascular abnormalities. Hyperplasia of the cardiac valves and outflow tract septation defects indicate a function for Smad6 in the regulation of endocardial cushion transformation. The role of Smad6 in the homeostasis of the adult cardiovascular system is indicated by the development of aortic ossification and elevated blood pressure in viable mutants. These defects highlight the importance of Smad6 in the tissue-specific modulation of Tgf-beta superfamily signalling pathways in vivo.


Asunto(s)
Anomalías Cardiovasculares/genética , Sistema Cardiovascular/embriología , Sistema Cardiovascular/crecimiento & desarrollo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Músculo Liso Vascular/fisiología , Transducción de Señal/fisiología , Transactivadores/genética , Transactivadores/metabolismo , Animales , Proteínas de Unión al ADN/deficiencia , Femenino , Biblioteca Genómica , Homeostasis , Homocigoto , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos , Ratones Noqueados , Ratones Transgénicos , Músculo Liso Vascular/patología , Mutagénesis Insercional , Proteínas Recombinantes de Fusión/metabolismo , Mapeo Restrictivo , Proteína smad6 , Transactivadores/deficiencia
10.
Ann Rheum Dis ; 70(5): 864-7, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21177295

RESUMEN

OBJECTIVES: The genetic aetiology of osteoarthritis has not yet been elucidated. To enable a well-powered genome-wide association study (GWAS) for osteoarthritis, the authors have formed the arcOGEN Consortium, a UK-wide collaborative effort aiming to scan genome-wide over 7500 osteoarthritis cases in a two-stage genome-wide association scan. Here the authors report the findings of the stage 1 interim analysis. METHODS: The authors have performed a genome-wide association scan for knee and hip osteoarthritis in 3177 cases and 4894 population-based controls from the UK. Replication of promising signals was carried out in silico in five further scans (44,449 individuals), and de novo in 14 534 independent samples, all of European descent. RESULTS: None of the association signals the authors identified reach genome-wide levels of statistical significance, therefore stressing the need for corroboration in sample sets of a larger size. Application of analytical approaches to examine the allelic architecture of disease to the stage 1 genome-wide association scan data suggests that osteoarthritis is a highly polygenic disease with multiple risk variants conferring small effects. CONCLUSIONS: Identifying loci conferring susceptibility to osteoarthritis will require large-scale sample sizes and well-defined phenotypes to minimise heterogeneity.


Asunto(s)
Osteoartritis de la Cadera/genética , Osteoartritis de la Rodilla/genética , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Herencia Multifactorial , Polimorfismo de Nucleótido Simple
11.
Front Pharmacol ; 12: 679388, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34712131

RESUMEN

Introduction: Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disease with a poor prognosis and increasing incidence. Pirfenidone and nintedanib are the only approved treatments for IPF but have limited efficacy and their mechanisms of action are poorly understood. Here we have examined the effects of pirfenidone and nintedanib in a human model of lung fibrogenesis, and compared these with the putative anti-fibrotic compounds Lipoxin A4 (LXA4), and senicapoc, a KCa3.1 ion channel blocker. Methods: Early fibrosis was induced in cultured human lung parenchyma using TGFß1 for 7 days, ± pirfenidone, nintedanib, or LXA4. Pro-fibrotic responses were examined by RT-PCR, immunohistochemistry and soluble collagen secretion. Results: Thirty six out of eighty four IPF and fibrosis-associated genes tested were significantly upregulated by TGFß1 in human lung parenchyma with a ≥0.5 log2FC (n = 32). Nintedanib (n = 13) reduced the mRNA expression of 14 fibrosis-associated genes including MMPs (MMP1,-4,-13,-14), integrin α2, CXCR4 and PDGFB, but upregulated α-smooth muscle actin (αSMA). Pirfenidone only reduced mRNA expression for MMP3 and -13. Senicapoc (n = 11) previously attenuated the expression of 28 fibrosis-associated genes, including αSMA, several growth factors, collagen type III, and αV/ß6 integrins. Pirfenidone and nintedanib significantly inhibited TGFß1-induced fibroblast proliferation within the tissue, but unlike senicapoc, neither pirfenidone nor nintedanib prevented increases in tissue αSMA expression. LXA4 was ineffective. Conclusions: Pirfenidone and nintedanib demonstrate modest anti-fibrotic effects and provide a benchmark for anti-fibrotic activity of new drugs in human lung tissue. Based on these data, we predict that the KCa3.1 blocker senicapoc will show greater benefit than either of these licensed drugs in IPF.

12.
Immunopharmacol Immunotoxicol ; 32(1): 171-6, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19821644

RESUMEN

BACKGROUND AND AIM: The pharmacokinetics of clenbuterol in equine urine and blood was investigated. MATERIAL AND METHODS: Urine and blood samples were collected following 3-day multiple oral administrations. The samples were examined using enzyme-linked immunosorbent assay and further confirmed by solid phase extraction and capillary electrophoresis. RESULTS: Urinary clenbuterol was detectable until day 14 after the last dose. The urinary excretion of clenbuterol was characterized by a biphasic pattern. The half-lives of the bi-exponential elimination (t(1/2alpha) and t(1/2beta)) for urinary clenbuterol were about 12.1 and 48 hours. After a single oral administration (4 microg/kg) of clenbuterol, the half-life of serum clenbuterol was approximately 11.4 hours.


Asunto(s)
Agonistas Adrenérgicos beta/farmacocinética , Clenbuterol/administración & dosificación , Clenbuterol/farmacocinética , Administración Oral , Animales , Ensayo de Inmunoadsorción Enzimática , Femenino , Caballos , Masculino , Distribución Tisular
13.
Occup Med (Lond) ; 60(3): 184-92, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20423949

RESUMEN

AIMS: To evaluate current research on the health, safety and health promotion needs of older workers by identifying age-related change, whether older workers need support and evidence of successful intervention in the workplace. METHODS: Using a systematic review methodology, databases were searched identifying 180 publications. Each publication was reviewed and data were extracted. Evidence was assessed for quality using the three-star system. RESULTS: The review identified that there are a number of age-related physical and psychological changes. However, these changes can be moderated by increased physical activity, intellectual activity and other lifestyle factors. Sensory abilities are also subject to change but some of these can be accommodated via equipment or workplace adjustments. In reviewing accident data, although older workers are at a reduced risk of accidents, they are more at risk of fatal accidents. Ill-health data identify that many chronic diseases can be controlled and adjustments put in place in the work environment. A number of intervention studies were identified but few were of high quality. The research suggests that occupational health intervention can reduce the risk of early retirement from the workplace; health promotion interventions are seen as positive by older workers but it is important to ensure equal access to all workers in such promotions. CONCLUSIONS: The review identified that there are still a large number of research gaps including the lack of longitudinal research; no further analysis on fatal accidents or understanding of the high prevalence of musculoskeletal disorders and stress and anxiety in older workers.


Asunto(s)
Accidentes de Trabajo/estadística & datos numéricos , Envejecimiento , Promoción de la Salud/organización & administración , Salud Laboral , Ausencia por Enfermedad/estadística & datos numéricos , Lugar de Trabajo/organización & administración , Accidentes de Trabajo/mortalidad , Adolescente , Adulto , Factores de Edad , Anciano , Envejecimiento/fisiología , Envejecimiento/psicología , Enfermedad Crónica , Femenino , Promoción de la Salud/métodos , Trastornos de Estrés por Calor/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Enfermedades Musculoesqueléticas/epidemiología , Resistencia Física/fisiología , Equilibrio Postural/fisiología , Jubilación/estadística & datos numéricos , Factores de Riesgo , Administración de la Seguridad/organización & administración , Factores Sexuales , Reino Unido/epidemiología , Tolerancia al Trabajo Programado/fisiología , Carga de Trabajo , Adulto Joven
14.
J AOAC Int ; 93(2): 576-86, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20480906

RESUMEN

The automated method for enumeration of Escherichia coli, TEMPO EC, in foods uses a dehydrated culture medium and enumeration card containing 48 wells across three different dilutions for the automatic determination of the most probable number (MPN). The alternative method was compared in a multilaboratory collaborative study to AOAC Official Method 966.24. Six food types were artificially contaminated with E. coli: raw ground beef, bagged lettuce, cooked chicken, pasteurized crabmeat, frozen green beans, and pasteurized whole milk. All foods were analyzed for E. coli counts by 11 collaborating laboratories throughout the United States. Test portions from the six food types each contaminated at four different contamination levels were evaluated. The study demonstrated that the TEMPO EC method is a reliable, automated assay for the enumeration of E. coli in foods.


Asunto(s)
Recuento de Colonia Microbiana/métodos , Escherichia coli/metabolismo , Contaminación de Alimentos , Microbiología de Alimentos , Animales , Automatización , Bovinos , Pollos/microbiología , Análisis de los Alimentos , Laboratorios/normas , Carne/microbiología , Reproducibilidad de los Resultados , Proyectos de Investigación , Alimentos Marinos/microbiología , Verduras/microbiología
15.
Sci Total Environ ; 749: 142262, 2020 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-33370926

RESUMEN

The ecological restoration of ecosystem services and biodiversity is a key intervention used to reverse the impacts of anthropogenic activities such as mining. Assessment of the performance of restoration against completion criteria relies on biodiversity monitoring. However, monitoring usually overlooks soil microbial communities (SMC), despite increased awareness of their pivotal role in many ecological functions. Recent advances in cost, scalability and technology has led to DNA sequencing being considered as a cost-effective biological monitoring tool, particularly for otherwise difficult to survey groups such as microbes. However, such approaches for monitoring complex restoration sites such as post-mined landscapes have not yet been tested. Here we examine bacterial and fungal communities across chronosequences of mine site restoration at three locations in Western Australia to determine if there are consistent changes in SMC diversity, community composition and functional capacity. Although we detected directional changes in community composition indicative of microbial recovery, these were inconsistent between locations and microbial taxa (bacteria or fungi). Assessing functional diversity provided greater understanding of changes in site conditions and microbial recovery than could be determined through assessment of community composition alone. These results demonstrate that high-throughput amplicon sequencing of environmental DNA (eDNA) is an effective approach for monitoring the complex changes in SMC following restoration. Future monitoring of mine site restoration using eDNA should consider archiving samples to provide improved understanding of changes in communities over time. Expansion to include other biological groups (e.g. soil fauna) and substrates would also provide a more holistic understanding of biodiversity recovery.


Asunto(s)
Microbiota , Suelo , Biodiversidad , Ecosistema , Secuenciación de Nucleótidos de Alto Rendimiento , Microbiología del Suelo , Australia Occidental
16.
Science ; 292(5515): 267-70, 2001 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-11303098

RESUMEN

We compared the temporal variability of the heat content of the world ocean, of the global atmosphere, and of components of Earth's cryosphere during the latter half of the 20th century. Each component has increased its heat content (the atmosphere and the ocean) or exhibited melting (the cryosphere). The estimated increase of observed global ocean heat content (over the depth range from 0 to 3000 meters) between the 1950s and 1990s is at least one order of magnitude larger than the increase in heat content of any other component. Simulation results using an atmosphere-ocean general circulation model that includes estimates of the radiative effects of observed temporal variations in greenhouse gases, sulfate aerosols, solar irradiance, and volcanic aerosols over the past century agree with our observation-based estimate of the increase in ocean heat content. The results we present suggest that the observed increase in ocean heat content may largely be due to the increase of anthropogenic gases in Earth's atmosphere.

17.
Ann Bot ; 104(5): 833-44, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19620135

RESUMEN

BACKGROUND AND AIMS: The Sapindaceae is one of 17 plant families in which seed dormancy is caused by a water-impermeable seed or fruit coat (physical dormancy, PY). However, until now the water gap in Sapindaceae had not been identified. The primary aim of this study was to identify the water gap in Dodonaea petiolaris (Sapindaceae) seeds and to describe its basic morphology and anatomy. METHODS: Seed fill, viability, water-uptake (imbibition) and other characteristics were assessed for D. petiolaris seeds. The location and structure of the water gap were investigated using a blocking experiment, time series photography, scanning electron microscopy and light microscopy. Dodonaea petiolaris seeds with PY also were assessed for loss of PY at four ecologically significant temperatures under moist and dry conditions. Seeds of three other species of Sapindaceae were examined for presence of a water gap. KEY RESULTS: The water gap in D. petiolaris seeds was identified as a small plug in the seed coat adjacent to the hilum and opposite the area where the radicle emerges. The plug was dislodged (i.e. water gap opened = dormancy break) by dipping seeds in boiling water for 2.5 min or by incubating seeds on a moist substrate at 20/35 degrees C for 24 weeks. Layers of cells in the plug, including palisade and subpalisade, are similar to those in the rest of the seed coat. The same kind of water gap was found in three other species of Sapindaceae, Diplopeltis huegelii, Distichostemon hispidulus and Dodonaea aptera. CONCLUSIONS: Following dormancy break (opening of water gap), initial uptake of water by the seed occurs only through the water gap. Thus, the plug must be dislodged before the otherwise intact seed can germinate. The anatomy of the plug is similar to water gaps in some of the other plant families with PY.


Asunto(s)
Sapindaceae/fisiología , Semillas/fisiología , Germinación/fisiología , Microscopía Electrónica de Rastreo , Semillas/ultraestructura , Agua/fisiología
18.
J Intellect Disabil Res ; 53(3): 298-302, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19250390

RESUMEN

BACKGROUND: Aggressive challenging behaviour is common in adults with intellectual disability (ID) in long-term care facilities. The government's commitment to the closure of all facilities in England has led to concerns over how to manage this behaviour in the community. The aim of this study was to assess changes in aggressive challenging behaviour and psychotropic drug use in adults with ID following resettlement using a person-centred approach. METHOD: The Modified Overt Aggression Scale was administered to carers of 49 adults with ID prior to discharge from a long-stay hospital and 6 months and 1 year after community resettlement. RESULTS: All areas of aggressive challenging behaviour reduced significantly between baseline and 6 months following resettlement (P < 0.001). This reduction remained (but did not decrease further) at 1-year follow-up. CONCLUSIONS: Further work is needed to evaluate the role of environmental setting on aggressive challenging behaviour in adults with ID.


Asunto(s)
Agresión/psicología , Discapacidad Intelectual/psicología , Trastorno de la Conducta Social/psicología , Adulto , Anciano , Agresión/efectos de los fármacos , Antipsicóticos/efectos adversos , Antipsicóticos/uso terapéutico , Comorbilidad , Desinstitucionalización , Inglaterra , Femenino , Estudios de Seguimiento , Hogares para Grupos , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/rehabilitación , Inteligencia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Conducta Autodestructiva/diagnóstico , Conducta Autodestructiva/psicología , Conducta Autodestructiva/rehabilitación , Trastorno de la Conducta Social/diagnóstico , Trastorno de la Conducta Social/rehabilitación , Medio Social
19.
Plant Biol (Stuttg) ; 21(3): 415-424, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30076679

RESUMEN

Grasslands across the globe are undergoing expansive degradation due to human impacts and climate change. If restoration of degraded native grassland is to be achieved at the scale now required, cost-effective means for seed-based establishment of grass species is crucial. However, grass seeds present numerous challenges associated with handling and germination performance that must be overcome to improve the efficiency of seeding. Previous research has demonstrated that complete removal of the palea and lemma (husk) maximises germination performance, hence we investigated the effects of complete husk removal on seed handling and germination of four temperate Australian grass species. Three techniques were tested to remove the husk - manual cleaning, flaming or acid digestion (the latter two followed by a manual cleaning step); these techniques were refined and adapted to the selected species, and germination responses were compared. The complete removal of the husk improved seed handling and sowability for all species. Germination was improved in Microlaena stipoides by 19% and in Rytidosperma geniculatum by 11%. Of the husk removal methods tested, flaming was detrimental to seed germination and fatal for one species (R. geniculatum). Compared to manual cleaning, sulphuric acid improved the overall efficacy of the cleaning procedure and increased germination speed (T50) in Austrostipa scabra, Chloris truncata and M. stipoides, and improved final germination in R. geniculatum by 13%. The seed processing methods developed and tested in the present study can be applied to grass species that present similar handling and germination performance impediments. These and other technological developments (seed coating and precision sowing) will facilitate more efficient grassland restoration at large scale.


Asunto(s)
Germinación/fisiología , Poaceae/fisiología , Semillas/fisiología , Conservación de los Recursos Naturales , Ecología
20.
Plant Biol (Stuttg) ; 21(3): 458-469, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30098068

RESUMEN

In degraded dryland systems, native plant community re-establishment following disturbance is almost exclusively carried out using seeds, but these efforts commonly fail. Much of this failure can be attributed to the limited understanding of seed dormancy and germination traits. We undertook a systematic classification of seed dormancy of 26 species of annual and perennial forbs and shrubs that represent key, dominant genera used in restoration of the Great Basin ecosystem in the western United States. We examined germination across a wide thermal profile to depict species-specific characteristics and assessed the potential of gibberellic acid (GA3 ) and karrikinolide (KAR1 ) to expand the thermal germination envelope of fresh seeds. Of the tested species, 81% produce seeds that are dormant at maturity. The largest proportion (62%) exhibited physiological (PD), followed by physical (PY, 8%), combinational (PY + PD, 8%) and morphophysiological (MPD, 4%) dormancy classes. The effects of chemical stimulants were temperature- and species-mediated. In general, mean germination across the thermal profile was improved by GA3 and KAR1 for 11 and five species, respectively. We detected a strong germination response to temperature in freshly collected seeds of 20 species. Temperatures below 10 °C limited the germination of all except Agoseris heterophylla, suggesting that in their dormant state, the majority of these species are thermally restricted. Our findings demonstrate the utility of dormancy classification as a foundation for understanding the critical regenerative traits in these ecologically important species and highlight its importance in restoration planning.


Asunto(s)
Ecosistema , Germinación/fisiología , Latencia en las Plantas/fisiología , Semillas/fisiología , Furanos/metabolismo , Giberelinas/metabolismo , Piranos/metabolismo , Semillas/metabolismo , Temperatura , Estados Unidos
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