Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 98
Filtrar
1.
Environ Int ; 186: 108587, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38579450

RESUMO

Air pollution is a key global environmental problem raising human health concern. It is essential to comprehensively assess the long-term characteristics of air pollution and the resultant health impacts. We first assessed the global trends of fine particulate matter (PM2.5) during 1980-2020 using a monthly global PM2.5 reanalysis dataset, and evaluated their association with three types of climate variability including El Niño-Southern Oscillation, Indian Ocean Dipole and North Atlantic Oscillation. We then estimated PM2.5-attributable premature deaths using integrated exposure-response functions. Results show a significant increasing trend of ambient PM2.5 during 1980-2020 due to increases in anthropogenic emissions. Ambient PM2.5 caused a total of âˆ¼ 135 million premature deaths globally during the four decades. Occurrence of air pollution episodes was strongly associated with climate variability, which were associated with up to 14 % increase in annual global PM2.5-attributable premature deaths.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Saúde Global , Material Particulado , Material Particulado/análise , Poluição do Ar/estatística & dados numéricos , Humanos , Poluentes Atmosféricos/análise , Mudança Climática , Exposição Ambiental/estatística & dados numéricos , Clima , Mortalidade Prematura
2.
NPJ Precis Oncol ; 6(1): 54, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906273

RESUMO

Glioblastoma is an aggressive brain cancer characterized by diffuse infiltration. Infiltrated glioma cells persist in the brain post-resection where they interact with glial cells and experience interstitial fluid flow. We use patient-derived glioma stem cells and human glial cells (i.e., astrocytes and microglia) to create a four-component 3D model of this environment informed by resected patient tumors. We examine metrics for invasion, proliferation, and putative stemness in the context of glial cells, fluid forces, and chemotherapies. While the responses are heterogeneous across seven patient-derived lines, interstitial flow significantly increases glioma cell proliferation and stemness while glial cells affect invasion and stemness, potentially related to CCL2 expression and differential activation. In a screen of six drugs, we find in vitro expression of putative stemness marker CD71, but not viability at drug IC50, to predict murine xenograft survival. We posit this patient-informed, infiltrative tumor model as a novel advance toward precision medicine in glioblastoma treatment.

3.
Vet Parasitol Reg Stud Reports ; 31: 100725, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35569907

RESUMO

Blowfly strike or cutaneous myiasis, caused principally by the Australian sheep blowfly Lucilia cuprina is endemic to Australian sheep producing areas and is a major cause of suffering and economic loss. This article reports incidence and control practices as determined by three cross-sectional surveys of Australian sheep farmers covering the years 2003 (n = 1365), 2011 (n = 575) and 2018 (n = 354) with more questions relating to blowfly strike in the latter two surveys. Breech strike was reported at a higher rate than body strike in all survey years. Reported annual incidence of breech strike ranged from 2.2 to 4.7% of sheep nationally with minor differences between ewes and lambs. The incidence of body strike ranged from 1.0 to 7.1% with higher incidence in younger sheep in all years. The use of fixed time routine preventative chemical treatments increased during the survey period (43%, 46% and 66%, in 2003, 2011 and 2018 respectively) with dicyclanil (54%-58%) and cyromazine (23-36%) the main insecticides used for control since 2011. The use of the Mules operation (mulesing) to remove skin wrinkles from the breech area as a preventative modification did not change between 2011 and 2018 (47% in both), however, the use of pain relief at mulesing of replacement ewe lambs increased substantially between 2011 (59%) and 2018 (87%). The most commonly used methods to assist with flystrike control were timing of crutching (clipping of wool from susceptible areas) and shearing, with few respondents destroying maggots from treated sheep (21-26%) and very low use of fly traps (5-8%). Phenotypic selection of ewes for reduced susceptibility to flystrike based on visual traits was practiced by 61% of respondents in 2011 and 56% in 2018. Selection of rams for reduced susceptibility using estimated breeding values increased from 10% in 2011 to 17% in 2018. Breeding for resistance was the most commonly nominated (21%) most important change made to flystrike management in 2018. The results indicate that concern for sheep welfare has increased with almost universal use of pain relief at mulesing. Increased use of selection for blowfly resistance indicates farmer commitment to planning for a future without mulesing, although the practice remains prevalent. An increase in the reliance on preventative chemical treatments increases the risk of insecticide resistance.


Assuntos
Calliphoridae , Doenças dos Ovinos , Animais , Austrália/epidemiologia , Cruzamento , Estudos Transversais , Feminino , Incidência , Masculino , Dor/epidemiologia , Dor/prevenção & controle , Dor/veterinária , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle , Inquéritos e Questionários
4.
Vet Parasitol Reg Stud Reports ; 27: 100662, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35012719

RESUMO

The sheep body louse (Bovicola ovis) is a parasite of major economic concern in Australia. This article reports lice incidence and control practices on Australian sheep farms as determined by three cross-sectional surveys of the years 2003, 2011 and 2018. The incidence of live lice detected within a flock was similar across the survey years with a slight decline in 2018 (2003: 20%, 2011: 18.6% and 2018: 13.9%). In an average year, most farmers did not see any direct or indirect evidence of lice infestation (2011: 59.3% and 2018: 69.5%), however, over a five-year period 38.9% (2003), 66.3% (in 2011) and 55.8% (in 2018) reported seeing evidence of lice infestation at least once with significant variation between sheep producing regions in 2011. In an average year, nearly three quarters of respondents treated for lice (2011:73.5% and 2018: 73.3%) with the majority treating immediately following shearing and very few treating sheep with long wool. Even higher percentages treated for lice at least once in the preceding five-year period (2011: 86.2% and 2018: 87.5%). Backliner was the most popular method of chemical application for lice control in sheep off-shears or with short wool (2003: 77%, 2011: 73% and 2018: 74.3%). For long wool treatments, hand jetting declined in popularity from 2003 (64%) to 2011 (54%) and 2018 (8.6%) as backliners became more popular (2003: 36%, 2011: 51% and 2018: 60%). The use of benzoylphenyl urea insect growth regulators (IGR) for off-shears/short wool treatment declined from 2003 (92.8%) to 2011 (51%) and 2018 (2.9%) and were largely replaced by neonicotinoids and spinosad for backliner/spray-on products. The use of organophosphates declined for plunge dipping (2003: 83.8%, 2011: 83% and 2018: 7.7%). Spinosad use for plunge dipping off-shears/short wool increased over the survey years (2003, 0%, 2011: 9% and 2018:46.2%). The use of IGRs declined for backliner application on long wool and were mainly replaced by spinosad in 2011 and 2018. Fewer respondents reported suspected resistance to lice control products in 2018 (8%) compared with 2003 (26%) and 2011 (13%) with most reporting suspected resistance to IGR and synthetic pyrethroids and emerging suspicions of resistance to neonicotinoids in 2018. Resistance to lice control products also reduced in importance as a reason for recurring lice infestations between 2011 (ranked 2nd) and 2018 (ranked 6th). Biosecurity was important to sheep producers with the highest ranked reason for recurring lice infestations being from stray or purchased sheep.


Assuntos
Iscnóceros , Doenças dos Ovinos , Animais , Austrália/epidemiologia , Controle de Doenças Transmissíveis , Estudos Transversais , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/prevenção & controle , Inquéritos e Questionários
5.
Hum Fertil (Camb) ; 25(2): 397-406, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32896180

RESUMO

An online, cross-sectional survey was carried out between November 2017 and January 2018 to assess fertility awareness among students attending the National Autonomous University of Mexico (UNAM) in Mexico City. A total of 371 students participated in the survey (n = 228 females, 143 males). 75% of females and 74% of males believed a woman's fertility begins to decline markedly after age 40. Over 75% of all participants overestimated the probability of couples having a live birth after undergoing one cycle of IVF. With regard to parenting intentions, only 48% of females wished to have children compared to 59% of males (p = 0.037) and men were more likely to have their first child at age 30 or later (71% men vs 55% women). In the event of infertility, participants had a higher preference not to have children or to pursue adoption rather than use in vitro fertilisation (IVF). In summary, university students in Mexico City demonstrated low levels of fertility awareness and a smaller proportion indicated a wish to have children than has been reported by young people elsewhere in the world.


Assuntos
Intenção , Poder Familiar , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Fertilidade , Humanos , Masculino , México , Estudantes , Universidades
6.
Earths Future ; 10(11): e2022EF002751, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36590252

RESUMO

Sea level rise (SLR) is a long-lasting consequence of climate change because global anthropogenic warming takes centuries to millennia to equilibrate for the deep ocean and ice sheets. SLR projections based on climate models support policy analysis, risk assessment and adaptation planning today, despite their large uncertainties. The central range of the SLR distribution is estimated by process-based models. However, risk-averse practitioners often require information about plausible future conditions that lie in the tails of the SLR distribution, which are poorly defined by existing models. Here, a community effort combining scientists and practitioners builds on a framework of discussing physical evidence to quantify high-end global SLR for practitioners. The approach is complementary to the IPCC AR6 report and provides further physically plausible high-end scenarios. High-end estimates for the different SLR components are developed for two climate scenarios at two timescales. For global warming of +2°C in 2100 (RCP2.6/SSP1-2.6) relative to pre-industrial values our high-end global SLR estimates are up to 0.9 m in 2100 and 2.5 m in 2300. Similarly, for a (RCP8.5/SSP5-8.5), we estimate up to 1.6 m in 2100 and up to 10.4 m in 2300. The large and growing differences between the scenarios beyond 2100 emphasize the long-term benefits of mitigation. However, even a modest 2°C warming may cause multi-meter SLR on centennial time scales with profound consequences for coastal areas. Earlier high-end assessments focused on instability mechanisms in Antarctica, while here we emphasize the importance of the timing of ice shelf collapse around Antarctica. This is highly uncertain due to low understanding of the driving processes. Hence both process understanding and emission scenario control high-end SLR.

7.
Science ; 368(6495): 1118-1121, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32499441

RESUMO

The response of mangroves to high rates of relative sea level rise (RSLR) is poorly understood. We explore the limits of mangrove vertical accretion to sustained periods of RSLR in the final stages of deglaciation. The timing of initiation and rate of mangrove vertical accretion were compared with independently modeled rates of RSLR for 78 locations. Mangrove forests expanded between 9800 and 7500 years ago, vertically accreting thick sequences of organic sediments at a rate principally driven by the rate of RSLR, representing an important carbon sink. We found it very likely (>90% probability) that mangroves were unable to initiate sustained accretion when RSLR rates exceeded 6.1 millimeters per year. This threshold is likely to be surpassed on tropical coastlines within 30 years under high-emissions scenarios.


Assuntos
Elevação do Nível do Mar , Áreas Alagadas
8.
Parasitology ; 146(4): 413-424, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30318029

RESUMO

Giardia duodenalis is a ubiquitous flagellated protozoan parasite known to cause giardiasis throughout the world. Potential transmission vehicles for this zoonotic parasite are both water and food sources. As such consumption of water contaminated by feces, or food sources washed in contaminated water containing parasite cysts, may result in outbreaks. This creates local public health risks which can potentially cause widespread infection and long-term post-infection sequelae. This paper provides an up-to-date overview of G. duodenalis assemblages, sub-assemblages, hosts and locations identified. It also summarizes knowledge of potential infection/transmission routes covering water, food, person-to-person infection and zoonotic transmission from livestock and companion animals. Public health implications focused within the UK, based on epidemiological data, are discussed and recommendations for essential Giardia developments are highlighted.


Assuntos
Giardia lamblia/fisiologia , Giardíase , Animais , Giardíase/diagnóstico , Giardíase/epidemiologia , Giardíase/transmissão , Giardíase/veterinária , Humanos , Saúde Pública , Fatores de Risco , Reino Unido
9.
Gen Comp Endocrinol ; 273: 184-191, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29990493

RESUMO

Studies of birds have greatly advanced our understanding of how testosterone modulates complex phenotypes, specifically its role in mediating male reproductive and associated behaviors. Yet most of the foundational studies have been limited to northern latitude breeding species despite the fact that they represent only a small fraction of worldwide avian diversity. In contrast, phylogenetic, life-history, and mating system diversity all reach their apex in neotropical avifauna and yet these birds, along with more southern latitude species, remain very poorly understood from an endocrine perspective. Despite the relatively limited previous work on taxa breeding in Central and South America, empirical findings have had a disproportionately large impact on our understanding of testosterone's role in everything from geographic variation to behavioral roles and neuroplasticity. Here, we synthesize how studies of neotropical breeding avifauna have advanced our understanding of how testosterone's actions can and are associated with the broad patterns of phenotypic diversity that we see in birds. In addition, we outline how these studies can be used individually or in a comparative context to address fundamental questions about the environmental endocrinology of testosterone and to understand the diversity of roles that testosterone plays in mediating behavioral variation, reproductive strategies, and associated life-history trade-offs.


Assuntos
Aves/metabolismo , Endocrinologia , Meio Ambiente , Testosterona/metabolismo , Clima Tropical , Animais , Feminino , Masculino , Plasticidade Neuronal
10.
J Microbiol Methods ; 145: 28-36, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29246779

RESUMO

Continuous and reliable monitoring of water sources for human consumption is imperative for public health. For protozoa, which cannot be multiplied efficiently in laboratory settings, concentration and recovery steps are key to a successful detection procedure. Recently, the use of megasonic energy was demonstrated to recover Cryptosporidium from commonly used water industry filtration procedures, forming thereby a basis for a simplified and cost effective method of elution of pathogens. In this article, we report the benefits of incorporating megasonic sonication into the current methodologies of Giardia duodenalis elution from an internationally approved filtration and elution system used within the water industry, the Filta-Max®. Megasonic energy assisted elution has many benefits over current methods since a smaller final volume of eluent allows removal of time-consuming centrifugation steps and reduces manual involvement resulting in a potentially more consistent and more cost-effective method. We also show that megasonic sonication of G. duodenalis cysts provides the option of a less damaging elution method compared to the standard Filta-Max® operation, although the elution from filter matrices is not currently fully optimised. A notable decrease in recovery of damaged cysts was observed in megasonic processed samples, potentially increasing the abilities of further genetic identification options upon isolation of the parasite from a filter sample. This work paves the way for the development of a fully automated and more cost-effective elution method of Giardia from water samples.


Assuntos
Água Potável/parasitologia , Giardia lamblia/isolamento & purificação , Giardíase/prevenção & controle , Sonicação/instrumentação , Doenças Transmitidas pela Água/prevenção & controle , Centrifugação/instrumentação , Água Potável/normas , Monitoramento Ambiental/economia , Monitoramento Ambiental/instrumentação , Filtração/instrumentação , Giardia lamblia/patogenicidade , Humanos , Sonicação/economia , Som , Microbiologia da Água/normas
11.
Sci Rep ; 7(1): 2601, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28572634

RESUMO

At present, there are few technologies which enable the detection, identification and viability analysis of protozoan pathogens including Cryptosporidium and/or Giardia at the single (oo)cyst level. We report the use of Microfluidic Impedance Cytometry (MIC) to characterise the AC electrical (impedance) properties of single parasites and demonstrate rapid discrimination based on viability and species. Specifically, MIC was used to identify live and inactive C. parvum oocysts with over 90% certainty, whilst also detecting damaged and/or excysted oocysts. Furthermore, discrimination of Cryptosporidium parvum, Cryptosporidium muris and Giardia lamblia, with over 92% certainty was achieved. Enumeration and identification of (oo)cysts can be achieved in a few minutes, which offers a reduction in identification time and labour demands when compared to existing detection methods.


Assuntos
Criptosporidiose/diagnóstico , Cryptosporidium parvum/fisiologia , Giardia lamblia/fisiologia , Giardíase/diagnóstico , Técnicas Analíticas Microfluídicas , Oocistos/fisiologia , Animais , Células Cultivadas , Diagnóstico Diferencial , Impedância Elétrica , Citometria de Fluxo , Humanos , Sensibilidade e Especificidade , Análise de Célula Única , Especificidade da Espécie
12.
Genes Brain Behav ; 14(8): 641-54, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26463687

RESUMO

The genome of the white-throated sparrow (Zonotrichia albicollis) contains an inversion polymorphism on chromosome 2 that is linked to predictable variation in a suite of phenotypic traits including plumage color, aggression and parental behavior. Differences in gene expression between the two color morphs, which represent the two common inversion genotypes (ZAL2/ZAL2 and ZAL2/ZAL2(m) ), may therefore advance our understanding of the molecular underpinnings of these phenotypes. To identify genes that are differentially expressed between the two morphs and correlated with behavior, we quantified gene expression and terrirorial aggression, including song, in a population of free-living white-throated sparrows. We analyzed gene expression in two brain regions, the medial amygdala (MeA) and hypothalamus. Both regions are part of a 'social behavior network', which is rich in steroid hormone receptors and previously linked with territorial behavior. Using weighted gene co-expression network analyses, we identified modules of genes that were correlated with both morph and singing behavior. The majority of these genes were located within the inversion, showing the profound effect of the inversion on the expression of genes captured by the rearrangement. These modules were enriched with genes related to retinoic acid signaling and basic cellular functioning. In the MeA, the most prominent pathways were those related to steroid hormone receptor activity. Within these pathways, the only gene encoding such a receptor was ESR1 (estrogen receptor 1), a gene previously shown to predict song rate in this species. The set of candidate genes we identified may mediate the effects of a chromosomal inversion on territorial behavior.


Assuntos
Inversão Cromossômica , Comportamento Sexual Animal/fisiologia , Pardais/genética , Vocalização Animal/fisiologia , Agressão , Animais , Comportamento Animal/fisiologia , Receptor alfa de Estrogênio/genética , Feminino , Estudos de Associação Genética , Genoma , Masculino , Comportamento Social , Transcriptoma
13.
Science ; 349(6244): aaa4019, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26160951

RESUMO

Interdisciplinary studies of geologic archives have ushered in a new era of deciphering magnitudes, rates, and sources of sea-level rise from polar ice-sheet loss during past warm periods. Accounting for glacial isostatic processes helps to reconcile spatial variability in peak sea level during marine isotope stages 5e and 11, when the global mean reached 6 to 9 meters and 6 to 13 meters higher than present, respectively. Dynamic topography introduces large uncertainties on longer time scales, precluding robust sea-level estimates for intervals such as the Pliocene. Present climate is warming to a level associated with significant polar ice-sheet loss in the past. Here, we outline advances and challenges involved in constraining ice-sheet sensitivity to climate change with use of paleo-sea level records.

14.
Int Nurs Rev ; 61(2): 285-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24754539

RESUMO

The International Federation of Nurse Anesthetists is improving anaesthesia patient care through a voluntary Anesthesia Program Approval Process (APAP) for schools and programmes. It is the result of a coordinated effort by anaesthesia leaders from many nations to implement a voluntary quality improvement system for education. These leaders firmly believe that meeting international education standards is an important way to improve anaesthesia, pain management and resuscitative care to patients worldwide. By 2013, 14 anaesthesia programmes from France, Iceland, Indonesia, Philippines, Sweden, Switzerland, Netherlands, Tunisia and the USA had successfully completed the process. Additional programmes were scheduled for review in 2014. Faculty from these programmes, who have successfully completed APAP, show how anaesthesia educators throughout the world seek to continually improve education and patient care by pledging to meet common education standards. As national governments, education ministers and heads of education institutions work to decrease shortages of healthcare workers, they would benefit from considering the value offered by quality improvement systems supported by professional organizations. When education programmes are measured against standards developed by experts in a profession, policy makers can be assured that the programmes have met certain standards of quality. They can also be confident that graduates of approved programmes are appropriately trained healthcare workers for their citizens.


Assuntos
Acreditação/normas , Currículo/normas , Educação de Pós-Graduação em Enfermagem/normas , Cooperação Internacional , Enfermeiros Anestesistas/educação , Escolas de Enfermagem/normas , Sociedades de Enfermagem/organização & administração , Humanos , Objetivos Organizacionais
15.
Aust Vet J ; 92(1-2): 8-14, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24471876

RESUMO

OBJECTIVE: This study used a model of the development of wool damage caused by lice in long wool to examine the conditions under which treatment of the sheep is advisable on an economic basis. METHODS: The model uses the proportion of a flock showing visible signs of rubbing and the number of days until the next shearing to compare the cost of treatment (product plus labour) with production losses because of the reduction in wool value caused by lice. From the model output, guidelines are provided to inform producers of the most cost-effective option for lice control. RESULTS: Under normal conditions, if there are any signs of rubbing ≥140 days before shearing, then treatment was the best option. If signs of wool damage are not observed until there are ≤70 days before shearing, then the most cost-effective option is to not treat at all. Between these two periods, the time period in which not treating is the most cost-effective option decreases as the number of sheep visibly affected by lice increases. At higher wool values (A$70/head vs A$35), the option to treat is brought forward approximately 25 days, whereas at a low wool value (A$17.50/head) the period in which no treatment is the most cost-effective is extended by approximately 25 days. Treating only the visibly affected sheep is the best option only for a very short time for all wool values and treatment costs. CONCLUSION: The model provides guidelines for control of lice in long wool to minimise the net cost of infestation and limit unnecessary pesticide use.


Assuntos
Inseticidas/uso terapêutico , Infestações por Piolhos/veterinária , Modelos Econômicos , Ftirápteros/crescimento & desenvolvimento , Doenças dos Ovinos/parasitologia , Lã/economia , Animais , Simulação por Computador , Análise Custo-Benefício , Guias como Assunto , Inseticidas/economia , Infestações por Piolhos/economia , Infestações por Piolhos/parasitologia , Infestações por Piolhos/prevenção & controle , Ovinos , Doenças dos Ovinos/economia , Doenças dos Ovinos/prevenção & controle , Fatores de Tempo
17.
J Clin Densitom ; 10(3): 306-11, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17584510

RESUMO

The purpose of this study was to carry out an in vivo cross calibration for forearm bone mineral density (BMD) between a Hologic QDR2000 (Hologic Inc., Bedford MA, USA) and Lunar Prodigy (GE Healthcare, Madison WI, USA) during equipment upgrade. Nineteen subjects (17 females and 2 males, mean age 57 yr, range: 42-79yr) attending for routine dual energy X-ray absorptiometry scanning were recruited. BMD of the nondominant forearm was measured on both instruments. Cross-calibration equations were derived for total forearm, ultradistal radius and ulna, and 33% radius and ulna. A Bland & Altman plot was used to calculate the mean difference and limits of agreement between instruments. There were significant differences in BMD at all sites. The Prodigy BMD was 15% higher at the total forearm and 20-25% higher in the cortical regions of the 33% ulna and 33% radius. The differences are smaller in the ultradistal regions, as it appears that the Prodigy underestimates BMD at low BMD. The standard error of estimate about the cross calibration was such that it cannot be used to transfer individual patients between instruments, but could be applied to clinical trial data.


Assuntos
Absorciometria de Fóton/instrumentação , Densidade Óssea , Rádio (Anatomia) , Ulna , Adulto , Idoso , Calibragem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
18.
Med Vet Entomol ; 21(2): 153-67, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17550435

RESUMO

The blowfly, Lucilia cuprina Wiedemann (Diptera: Calliphoridae), is the primary myiasis (strike) fly of sheep in Australia. Most strike occurs in the anal-perineum area (crutch), but strike to the neck, shoulders, back and withers (body) is also important. Regression analysis was used to determine the extent to which the weekly incidence of flystrike can be explained by variations in fly abundance and/or recent changes in weather, pasture conditions or flock management. Strike and flock management data were collected by questionnaire surveys of 30-60 sheep properties in each of three major sheep-producing areas in southeastern Australia, namely, Gunning (southern New South Wales), Inverell (northern New South Wales) and Flinders Island (Bass Strait). After using simulation modelling to remove effects due to shearing, crutching and/or insecticide treatment, pasture growth index was found to be the most important explanatory variable affecting the incidence of all forms of myiasis. Others were average weekly air temperature, the amount and frequency of rainfall, relative humidity, dung quality index and a factor denoting seasonal effects. Together, these variables accounted for 48.4% of the variation in body strike, 56.8% of that in crutch strike and 51.9% of that in other forms of strike. Prediction was improved by the inclusion of additional lagged variables describing previous strike, fly abundance and fly activity. With these additions, the variation explained increased to 60.4% for body strike, 68.0% for crutch strike and 58.3% for other strikes.


Assuntos
Dípteros/patogenicidade , Modelos Biológicos , Modelos Estatísticos , Miíase/veterinária , Doenças dos Ovinos/epidemiologia , Tempo (Meteorologia) , Criação de Animais Domésticos/métodos , Animais , Austrália/epidemiologia , Feminino , Incidência , Inseticidas/administração & dosagem , Masculino , Miíase/epidemiologia , Miíase/prevenção & controle , Densidade Demográfica , Análise de Regressão , Ovinos , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/prevenção & controle
19.
Philos Trans A Math Phys Eng Sci ; 364(1841): 973-91, 2006 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-16537151

RESUMO

This paper provides a brief overview of the transfer function approach to sea-level reconstruction. Using the example of two overlapping sediment cores from the North Norfolk coast, UK, the advantages and limitations of the transfer function methodology are examined. While the selected cores are taken from different sites, and display contrasting patterns of sedimentation, the foraminiferal transfer function distils comparable records of relative sea-level change from both sequences. These reconstructions are consistent with existing sea-level index points from the region but produce a more detailed record of relative sea-level change. Transfer functions can extract sea-level information from a wider range of sedimentary sub-environments. This increases the amount of data that can be collected from coastal deposits and improves record resolution. The replicability of the transfer function methodology, coupled with the sequential nature of the data it produces, assists in the compilation and analysis of sea-level records from different sites. This technique has the potential to bridge the gap between short-term (instrumental) and long-term (geological or geophysical) records of sea-level change.


Assuntos
Coleta de Dados/métodos , Sedimentos Geológicos/análise , Oceanografia/métodos , Água do Mar , Fatores Etários , Altitude , Animais , Eucariotos/química , Oceanos e Mares , Reino Unido
20.
Med Vet Entomol ; 20(4): 445-52, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17199756

RESUMO

The significance of brushtail possum, Trichosurus vulpecula Kerr (Diprotodontia: Phalangeridae) carcasses to the succession and production of Diptera species and its relevance to fly strike management in Tasmania, Australia was examined. Calliphora stygia (Fabricius), Lucilia sericata (Meigen) and Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae) were found to be the most abundant and Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae) always the least abundant (< 1%) of the putative primary fly invading species to emerge. Carcasses that were left for up to 15 days in the field before being exposed to flies for 2 days also acted as breeding sites for large numbers of all primary fly species, with the exception of L. cuprina. Ordination analysis revealed no relationship between possum carcasses according to their length of exposure but did show significant negative associations between the number of putative secondary invaders (Chrysomya rufifacies (Macquart) (Diptera: Calliphoridae), Chrysomya varipes (Macquart) (Diptera: Calliphoridae) and putative tertiary flies (Hydrotaea rostrata Robineau-Desvoidy (Diptera: Muscidae)) to the number of C. vicina or C. stygia to emerge. There was enormous variability in the numbers of secondary/tertiary fly species to emerge from carcasses (0-11 450) that negatively correlated with the proportion of all flies to emerge that were primary, and with the mean size of adult L. sericata. Although carcass temperatures, especially those with a large larval population, were elevated, this did not appear to result in significant pre-adult fly mortality. The most important primary fly strike species L. cuprina was only found in insignificant numbers, whereas three other members of the fly strike fauna C. stygia, L. sericata and Ch. rufifacies did use possum carrion as an important breeding resource, but left implications for fly strike management inconclusive.


Assuntos
Dípteros/fisiologia , Ovinos , Trichosurus , Agricultura , Animais , Tasmânia , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA