RESUMEN
Understanding the spatial dynamics and drivers of wildlife pathogens is constrained by sampling logistics, with implications for advancing the field of landscape epidemiology and targeted allocation of management resources. However, visually apparent wildlife diseases, when combined with remote-surveillance and distribution modelling technologies, present an opportunity to overcome this landscape-scale problem. Here, we investigated dynamics and drivers of landscape-scale wildlife disease, using clinical signs of sarcoptic mange (caused by Sarcoptes scabiei) in its bare-nosed wombat (BNW; Vombatus ursinus) host. We used 53,089 camera-trap observations from over 3261 locations across the 68,401 km2 area of Tasmania, Australia, combined with landscape data and ensemble species distribution modelling (SDM). We investigated: (1) landscape variables predicted to drive habitat suitability of the host; (2) host and landscape variables associated with clinical signs of disease in the host; and (3) predicted locations and environmental conditions at greatest risk of disease occurrence, including some Bass Strait islands where BNW translocations are proposed. We showed that the Tasmanian landscape, and ecosystems therein, are nearly ubiquitously suited to BNWs. Only high mean annual precipitation reduced habitat suitability for the host. In contrast, clinical signs of sarcoptic mange disease in BNWs were widespread, but heterogeneously distributed across the landscape. Mange (which is environmentally transmitted in BNWs) was most likely to be observed in areas of increased host habitat suitability, lower annual precipitation, near sources of freshwater and where topographic roughness was minimal (e.g. human modified landscapes, such as farmland and intensive land-use areas, shrub and grass lands). Thus, a confluence of host, environmental and anthropogenic variables appear to influence the risk of environmental transmission of S. scabiei. We identified that the Bass Strait Islands are highly suitable for BNWs and predicted a mix of high and low suitability for the pathogen. This study is the largest spatial assessment of sarcoptic mange in any host species, and advances understanding of the landscape epidemiology of environmentally transmitted S. scabiei. This research illustrates how host-pathogen co-suitability can be useful for allocating management resources in the landscape.
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Marsupiales , Escabiosis , Animales , Humanos , Escabiosis/epidemiología , Efectos Antropogénicos , Ecosistema , Sarcoptes scabiei , Animales SalvajesRESUMEN
Saltmarsh breeding mosquitoes are an important source of vectors for arboviral transmission. In southern Australia, the most prominent vector borne disease, Ross River virus (Togaviridae: Alphavirus) (RRV), is transmitted by the saltmarsh mosquito (Diptera: Culicidae) Aedes camptorhynchus (Thomson). However, the factors driving the abundance of this mosquito within and among saltmarshes are poorly understood. To predict the abundance of this mosquito within saltmarshes, the environmental conditions and aquatic invertebrate ecology of three temperate saltmarshes habitats were monitored over two seasons. Up to 44% of first-instar mosquito numbers and 21% of pupal numbers were accounted for by environmental variables. Samphire vegetation cover was a common predictor of first-instar numbers across sites although, between saltmarshes, aquatic factors such as high salinity, temperatures less than 22 °C and water body volume were important predictors. The identified predictors of pupal numbers were more variable and included high tides, waterbody volume and alkalinity. The composition of invertebrate functional feeding groups differed between saltmarshes and showed that an increased diversity led to fewer mosquitoes. It was evident that apparently similar saltmarshes can vary markedly in invertebrate assemblages, water availability and conditions through tidal inundations, rainfall or waterbody permanency. The present study advances insight into predictors of vector mosquito numbers that drive the risk of RRV outbreaks.
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Aedes/fisiología , Mosquitos Vectores/fisiología , Virus del Río Ross/fisiología , Salinidad , Humedales , Infecciones por Alphavirus/transmisión , Animales , Frío , Dinámica Poblacional , TasmaniaRESUMEN
Most vector-borne diseases infect multiple host species, but disentangling the relative importance of different host species to transmission can be complex. Here we study how host species' abundance and competence (duration and titre of parasitaemia) influence host importance during epidemic scenarios. We evaluate this theory using Ross River virus (RRV, family Togaviridae, genus Alphavirus), a multi-host mosquito-borne disease with significant human health impacts across Australia and Papua New Guinea. We used host contribution models to find the importance of key hosts (possums, wallabies, kangaroos, horses, humans) in typical mammal communities around five Australian epidemic centres. We found humans and possums contributed most to epidemic RRV transmission, owing to their high abundances, generally followed by macropods. This supports humans as spillover hosts, and that human-mosquito and possum-mosquito transmission is predominant during epidemics. Sensitivity analyses indicate these findings to be robust across epidemic centres. We emphasize the importance of considering abundance and competence in identifying key hosts (during epidemics in this case), and that competence alone is inadequate. Knowledge of host importance in disease transmission may help to equip health agencies to bring about greater effectiveness of disease mitigation strategies.
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Infecciones por Alphavirus/epidemiología , Infecciones por Alphavirus/veterinaria , Reservorios de Enfermedades , Transmisión de Enfermedad Infecciosa , Vectores de Enfermedades , Epidemias , Virus del Río Ross/aislamiento & purificación , Infecciones por Alphavirus/transmisión , Animales , Animales Salvajes , Australia/epidemiología , Culicidae , Métodos Epidemiológicos , Humanos , Modelos Estadísticos , Papúa Nueva Guinea/epidemiologíaRESUMEN
Health warnings of mosquito-borne disease risk require forecasts that are accurate at fine-temporal resolutions (weekly scales); however, most forecasting is coarse (monthly). We use environmental and Ross River virus (RRV) surveillance to predict weekly outbreak probabilities and incidence spanning tropical, semi-arid, and Mediterranean regions of Western Australia (1991-2014). Hurdle and linear models were used to predict outbreak probabilities and incidence respectively, using time-lagged environmental variables. Forecast accuracy was assessed by model fit and cross-validation. Residual RRV notification data were also examined against mitigation expenditure for one site, Mandurah 2007-2014. Models were predictive of RRV activity, except at one site (Capel). Minimum temperature was an important predictor of RRV outbreaks and incidence at all predicted sites. Precipitation was more likely to cause outbreaks and greater incidence among tropical and semi-arid sites. While variable, mitigation expenditure coincided positively with increased RRV incidence (r 2 = 0·21). Our research demonstrates capacity to accurately predict mosquito-borne disease outbreaks and incidence at fine-temporal resolutions. We apply our findings, developing a user-friendly tool enabling managers to easily adopt this research to forecast region-specific RRV outbreaks and incidence. Approaches here may be of value to fine-scale forecasting of RRV in other areas of Australia, and other mosquito-borne diseases.
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Infecciones por Alphavirus/epidemiología , Brotes de Enfermedades , Virus del Río Ross/fisiología , Infecciones por Alphavirus/virología , Animales , Culicidae/virología , Predicción , Humanos , Incidencia , Probabilidad , Australia OccidentalRESUMEN
BACKGROUND: It has been proposed that non-steroidal anti-inflammatory drugs (NSAIDs) may interfere with the efficacy of antidepressants and contribute to treatment resistance in major depressive disorder (MDD). This effect requires replication and a test of whether it is specific to serotonin-reuptake inhibiting (SRI) antidepressants. METHOD: We tested the effect of concomitant medication with NSAIDs on the efficacy of escitalopram, a SRI antidepressant, and nortriptyline, a tricyclic antidepressant, among 811 subjects with MDD treated for up to 12 weeks in the GENDEP study. Effects of NSAIDs on improvement of depressive symptoms were tested in mixed-effect linear models. Effects on remission were tested in logistic regression. Age, sex, baseline severity and centre of recruitment were considered as potential confounding factors. RESULTS: Ten percent (n=78) of subjects were taking NSAIDs during the antidepressant treatment. Older subjects were significantly more likely to take NSAIDs. After controlling for age, sex, centre of recruitment and baseline severity, concomitant medication with NSAIDs did not significantly influence the efficacy of escitalopram [ß=0.035, 95% confidence interval (CI) -0.145 to 0.215, p=0.704] or nortriptyline (ß=0.075, 95% CI -0.131 to 0.281, p=0.476). Although slightly fewer subjects who took NSAIDs reached remission [odds ratio (OR) 0.80, 95% CI 0.49-1.31, p=0.383], this non-significant effect was reversed after controlling for age, sex, baseline severity and recruitment centre effects (OR 1.04, 95% CI 0.61-1.77, p=0.882). CONCLUSIONS: NSAIDs are unlikely to affect the efficacy of SRI or other antidepressants. Concurrent use of NSAIDs and antidepressants does not need to be avoided.
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Antiinflamatorios no Esteroideos/farmacología , Antidepresivos Tricíclicos/farmacología , Citalopram/farmacología , Trastorno Depresivo Mayor/tratamiento farmacológico , Nortriptilina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Adulto , Distribución por Edad , Interacciones Farmacológicas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Distribución por Sexo , Resultado del TratamientoRESUMEN
In Australia, Ross River virus (RRV) is predominantly identified and managed through passive health surveillance. Here, the proactive use of environmental datasets to improve community-scale public health interventions in southeastern Tasmania is explored. Known environmental drivers (temperature, rainfall, tide) of the RRV vector Aedes camptorhynchus are analysed against cumulative case records for five adjacent local government areas (LGAs) from 1993 to 2009. Allowing for a 0- to 3-month lag period, temperature was the most significant driver of RRV cases at 1-month lag, contributing to a 23·2% increase in cases above the long-term case average. The potential for RRV to become an emerging public health issue in Tasmania due to projected climate changes is discussed. Moreover, practical outputs from this research are proposed including the development of an early warning system for local councils to implement preventative measures, such as public outreach and mosquito spray programmes.
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Infecciones por Alphavirus/epidemiología , Culicidae/fisiología , Insectos Vectores/fisiología , Virus del Río Ross/fisiología , Infecciones por Alphavirus/prevención & control , Infecciones por Alphavirus/transmisión , Infecciones por Alphavirus/virología , Animales , Distribución Binomial , Culicidae/crecimiento & desarrollo , Culicidae/virología , Recolección de Datos , Humanos , Incidencia , Insectos Vectores/virología , Larva/fisiología , Larva/virología , Dinámica Poblacional , Práctica de Salud Pública , Lluvia , Análisis de Regresión , Estaciones del Año , Estadísticas no Paramétricas , Tasmania/epidemiología , Temperatura , Olas de MareaRESUMEN
Many small- and medium-sized mammals dig for their food. This activity potentially affects soil condition and fertility. Digging is well developed especially in Australian mammals, many of which have recently become rare or extinct. We measured the effects of digging by mammals on soil in a Tasmanian temperate dry sclerophyll forest with an intact mammal community. The density of diggings was 5812 ha-1, affecting 11% of the forest floor. Diggings were created at a rate of around 3113 diggings ha-1 yr-1, disturbing 6.5% of the forest floor and displacing 7.1 m3 ha-1 of soil annually. Most diggings were made by eastern bettongs (Bettongia gaimardi) and short-beaked echidnas (Tachyglossus aculeatus). Many (approx. 30%) fresh diggings consisted of re-excavations of old diggings. Novel diggings displaced 5 m3 ha yr-1 of soil. Diggings acted as traps for organic matter and sites for the formation of new soil, which had higher fertility and moisture content and lower hardness than undisturbed topsoil. These effects on soil fertility and structure were strongest in habitats with dry and poor soil. Creation of fine-scaled heterogeneity by mammals, and amelioration of dry and infertile soil, is a valuable ecosystem service that could be restored by reintroduction of digging mammals to habitats from which they have declined or gone extinct.
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We examined patterns in soil microbial community composition across a successional gradient of drained lake basins in the Arctic Coastal Plain. Analysis of 16S rRNA gene sequences revealed that methanogens closely related to Candidatus 'Methanoflorens stordalenmirensis' were the dominant archaea, comprising >50% of the total archaea at most sites, with particularly high levels in the oldest basins and in the top 57 cm of soil (active and transition layers). Bacterial community composition was more diverse, with lineages from OP11, Actinobacteria, Bacteroidetes, and Proteobacteria found in high relative abundance across all sites. Notably, microbial composition appeared to converge in the active layer, but transition and permafrost layer communities across the sites were significantly different to one another. Microbial biomass using fatty acid-based analysis indicated that the youngest basins had increased abundances of gram-positive bacteria and saprotrophic fungi at higher soil organic carbon levels, while the oldest basins displayed an increase in only the gram-positive bacteria. While this study showed differences in microbial populations across the sites relevant to basin age, the dominance of Candidatus 'M. stordalenmirensis' across the chronosequence indicates the potential for changes in local carbon cycling, depending on how these methanogens and associated microbial communities respond to warming temperatures.
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Archaea/genética , Bacterias/genética , Lagos/microbiología , Microbiología del Suelo , Alaska , Archaea/aislamiento & purificación , Regiones Árticas , Bacterias/aislamiento & purificación , Biomasa , Bases de Datos Genéticas , ARN Ribosómico 16S/química , ARN Ribosómico 16S/metabolismo , Análisis de Secuencia de ADNRESUMEN
A semi-continuous compression/perfusion system has been custom made to allow the application of intermittent hydrostatic pressure, at physiological levels, to regenerating tissues over the long term. To test the system, isolated foal chondrocytes were seeded in resorbable polyglycolic acid meshes and cultured in the system for 5 weeks. The cell/polymer constructs were subjected to an intermittent hydrostatic pressure of 500 psi and were fed semi-continuously. Assays of the resulting tissue constructs indicate that the reactor supports cartilage development and that physiological intermittent compression enhances the production of extracellular matrix by the chondrocytes. The concentrations of sulfated glycosaminoglycan were found to be at least twice as high as those in control (unpressurized) samples. A correlation between the sulfated glycosaminoglycan content and the compressive modulus in pressurized, but not control, samples suggests that physiological intermittent pressurization not only enhances the production of extracellular matrix but may also influence matrix organization resulting in a stronger construct.
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Cartílago Articular/fisiología , Regeneración/fisiología , Animales , Materiales Biocompatibles , Cartílago Articular/citología , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Glucosa/metabolismo , Caballos , Presión Hidrostática , Consumo de Oxígeno , Perfusión/instrumentación , Perfusión/métodos , Ácido Poliglicólico , Factores de TiempoRESUMEN
Mutation response at the HGPRT locus has been compared in two differing cell lines: V79/4, an aneuploid Chinese-hamster fibroblast line with a complement of 20 chromosomes, and BHK21-C13, a diploid Syrian-hamster fibroblast line with a complement of 44 chromosomes. The data presented show that BHK is slightly more radiosensitive than V79/4; however, the toxicity curves and expression times are similar for both cell lines. If radiosensitivity is taken into account, a common line can be drawn for radiation mutagenesis. We conclude from the data that radiation-induced mutagenesis is broadly equivalent in the two cell lines examined, and is not dependent on the chromosome complement.
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Fibroblastos/efectos de la radiación , Hipoxantina Fosforribosiltransferasa/genética , Animales , Línea Celular , Supervivencia Celular/efectos de la radiación , Cricetinae , Cricetulus/genética , Fibroblastos/efectos de los fármacos , Fibroblastos/enzimología , Genes/efectos de la radiación , Riñón , Pulmón , Masculino , Mesocricetus/genética , Tolerancia a Radiación , Tioguanina/farmacologíaRESUMEN
The exit time decomposition of a set yields a description of the transport through the set as well as a visualization of the invariant structures inside it. We construct several sets computationally easier to deal with than the construction of resonances, based on the ordering properties for orbits of twist maps. Furthermore these sets can be constructed for four- and higher-dimensional twist mappings. For the four-dimensional case-using the example of Froeshle-we find "practically" invariant volumes surrounding elliptic fixed points. The boundaries of these regions are remarkably sharp; however, the regions are threaded by "tubes" of escaping orbits.
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It was always my belief that perioperative nurses should be in the operating room performing nursing duties, not in the role of cleaning instruments and picking tables. New technology introduced over the past decade required longer schedules for nurses and the introduction of additional support staff. Because of the longer schedules, it became more cost effective to hire support staff to assist nurses in non-nursing functions. Recently, I was involved in a program which reorganized one aspect of our OR department and merged two existing support positions into one. Using ORNAC standards, CAS standards and CSS standards, I accepted the challenge of organizing the supplies of the department, merging orderlies and aides into one support group, training and documenting the important assignments given to this group and orienting staff to this new role.
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Técnicos Medios en Salud/estadística & datos numéricos , Enfermería de Quirófano , Técnicos Medios en Salud/educación , Humanos , Capacitación en Servicio , Enfermería de Quirófano/organización & administración , Recursos HumanosRESUMEN
In this paper, we propose a signal processing method of assessing the severity tremors caused by alcohol withdrawal (AW) syndrome. We have developed an iOS application to calculate the Clinical Institute Withdrawal Assessment (CIWA) score which captures iPod movements using the built-in accelerometer in order to reliably estimate the tremor severity component of the score. We report on the characteristics of AW tremor, the accuracy of electronic assessment of tremor compared to expert clinician assessment, and the potential for using signal processing assessment to differentiate factitious from real tremor in patients seen in the emergency department, as well as in nurses mimicking a tremor. Our preliminary results are based on 84 recordings from 61 subjects (49 patients, 12 nurses). In general we found a linear relationship between energy measured by the accelerometer (in the 4.4-10 Hz range) and the expert rating of tremor severity. Additionally, we demonstrate that 75% of the recordings from patients with actual AW syndrome had a mean peak frequency higher than 7 Hz whereas only 17% of the nurses' factitious tremors were above 7 Hz, suggesting that tremor above 7 Hz could be a potential discriminator of real versus factitious tremors.
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Trastornos del Sistema Nervioso Inducidos por Alcohol/diagnóstico , Síndrome de Abstinencia a Sustancias/diagnóstico , Temblor/diagnóstico , Acelerometría , Trastornos del Sistema Nervioso Inducidos por Alcohol/fisiopatología , Humanos , Actividad Motora , Síndrome de Abstinencia a Sustancias/fisiopatología , Factores de Tiempo , Temblor/fisiopatologíaAsunto(s)
Bradicardia/complicaciones , Enfermedad Coronaria/mortalidad , Bradicardia/mortalidad , Bradicardia/fisiopatología , Enfermedad Coronaria/complicaciones , Muerte Súbita , Complicaciones de la Diabetes , Electrocardiografía , Sistema de Conducción Cardíaco/fisiopatología , Frecuencia Cardíaca , Humanos , Hipertensión/complicaciones , Enfermedades Pulmonares/complicaciones , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , New York , Estudios ProspectivosAsunto(s)
Arritmias Cardíacas/epidemiología , Sistema de Conducción Cardíaco/fisiología , Personal Administrativo , Arritmias Cardíacas/clasificación , Enfermedad Coronaria/mortalidad , Enfermedad Coronaria/fisiopatología , Electrocardiografía , Estudios de Seguimiento , Bloqueo Cardíaco/epidemiología , Humanos , Masculino , Anamnesis , Persona de Mediana Edad , New Jersey , Medicina del Trabajo , Examen Físico , Taquicardia/epidemiología , Taquicardia Paroxística/epidemiologíaAsunto(s)
Complejos Cardíacos Prematuros/complicaciones , Enfermedad Coronaria/complicaciones , Adulto , Anciano , Arritmias Cardíacas/complicaciones , Complejos Cardíacos Prematuros/epidemiología , Complejos Cardíacos Prematuros/fisiopatología , Enfermedad Coronaria/mortalidad , Muerte Súbita , Electrocardiografía , Ventrículos Cardíacos/fisiopatología , Humanos , Hipertensión/complicaciones , Enfermedades Pulmonares Obstructivas/complicaciones , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Taquicardia/complicacionesRESUMEN
With all of its promise, the Internet is virtually impossible for a benefits administrator to ignore, but implementing an Internet-enabled benefits administration system is not without its challenges. However, with the proper care and planning, any employer, regardless of size or employee population, can successfully leverage this technology to simplify benefits administration, reduce costs and improve the level of service to plan participants.
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Planes de Asistencia Médica para Empleados/organización & administración , Internet/organización & administración , Comunicación , Toma de Decisiones en la Organización , Planes de Asistencia Médica para Empleados/estadística & datos numéricos , Educación en Salud , Humanos , Internet/normas , Missouri , Estudios de Casos Organizacionales , Técnicas de Planificación , Estados UnidosRESUMEN
Research in psychophysics (Bloch's law) and perceptual experiments concerned with the integration of successively presented stimuli suggest that the perception of form is a process that occurs over a period of as much as 200-300 msec. Such results prompted the question of whether the visual evoked potential (VEP) might contain information about the distribution over time of perceptual processing. Subjects viewed lines formed from combinations of three lengths and four angles while the EEG was recorded. Analysis of the VEPs indicated that the length and angle of the lines produced temporal distributions of information in the VEP and that the distributions for length and angle were somewhat different. The major difference was that the processing of angle begins earlier and is completed sooner than the processing of length. A conclusion of the experiment was that an alternative or supplement to analyzing VEPs for specific waveform features is to consider the encoding of stimulus information in the VEP as a density or concentration over time.