982 research outputs found
Impacts of dieback at Pine Lake, Tasmania
The possibility of a new plant disease in alpine plant communities was identified in 1994, following an investigation of dead and dying plants in the Central Plateau Conservation Area. Seven areas of dieback were identified within the affected catchment and monitored.
Symptoms included leaf discolouration, loss of foliage and plant death. No disease of this type has previously been recorded in the Australian alpine environment. Temporal and spatial patterns in disease development along with evidence of lesions on plant roots suggested a soil and water-borne pathogen could be contributing to the dieback. A species of Phytophthora was isolated from plant material collected at the site.
Investigations have focussed on whether plants at the limits of their range have been more susceptible to a combination of below-average rainfall, above-average temperatures and the presence of pathogens. Initial rapid development of disease symptoms suggested the potential for local extinction of species, including Tasmanian endemics such as Athrotaxis cupressoides, and significant alteration to community structure through a loss or substantial reduction in the tree and shrub layers. However, longer term monitoring suggests short-term disease events followed by recovery of surviving plants with only localised impacts. Management actions have been concentrated on containment,
monitoring impacts and investigation of the cause of the dieback
Quick returns and night work as predictors of sleep quality, fatigue, work–family balance and satisfaction with work hours
<p>Quick returns (intervals of <11 h between the end of one shift and the start of the next) are associated with short sleeps and fatigue on the subsequent shift. Recent evidence suggests that shift workers regard quick returns as being more problematic than night work. The current study explored quick returns and night work in terms of their impact on sleep, unwinding, recovery, exhaustion, satisfaction with work hours and work–family interference. Data from the 2006 cohort of Swedish nursing students within the national Longitudinal Analysis of Nursing Education (LANE) study were analysed (<i>N</i> = 1459). Respondents completed a questionnaire prior to graduation (response rate 69.2%) and 3 years after graduation (65.9%). The analyses examined associations between frequency of quick returns and night work and measures taken in year three, while adjusting for confounding factors (in year three and prior graduation). Frequency of quick returns was a significant predictor of poor sleep quality, short sleeps, unwinding, exhaustion, satisfaction with work hours and work-to-family interference, with higher frequency predicting more negative outcomes. Quick returns did not predict recovery after rest days. Frequency of night work did not predict any of the outcomes. In conclusion, quick returns were an important determinant of sleep, recovery and wellbeing, whereas night work did not show such an association.</p
Una Vida Sin Palabras?: Disability, Subalternity and the Sandinista Revolution
This paper offers an analysis of the documentary film, Una Vida Sin Palabras [A life without words] (2011). The film follows a short period in the lives of a campesino family living in a rural area of Nicaragua as a teacher of Nicaraguan sign language, working for a local NGO, endeavours to teach three deaf siblings how to sign. Bringing together the critical practices of Disability and Subaltern studies in the specific context of contemporary Nicaragua, the paper argues: (1) that the film ultimately re-inscribes and reinforces the subalternity of the disabled subjects it sets out to portray; and (2) that the hierarchy it produces between its object – the deaf family – and its implied educated, metropolitan audience replays some influential (but, we would argue, politically limited) critiques of the failure of the first Sandinista Government (1979-1990) and other broad based radical political movements to represent the national popular. In so doing, the paper also makes a case for the political and intellectual importance of bringing a Critical Disability Studies perspective to the field of Subaltern Studies, and argues that an engagement with the problems that are presented by this film at the level of both form and content raise some important questions for both fields of enquiry
Advanced orbit transfer vehicle propulsion system study
A reuseable orbit transfer vehicle concept was defined and subsequent recommendations for the design criteria of an advanced LO2/LH2 engine were presented. The major characteristics of the vehicle preliminary design include a low lift to drag aerocapture capability, main propulsion system failure criteria of fail operational/fail safe, and either two main engines with an attitude control system for backup or three main engines to meet the failure criteria. A maintenance and servicing approach was also established for the advanced vehicle and engine concepts. Design tradeoff study conclusions were based on the consideration of reliability, performance, life cycle costs, and mission flexibility
Current and projected global distribution of Phytophthora cinnamomi, one of the world's worst plant pathogens
Globally, Phytophthora cinnamomi is listed as one of the 100 worst invasive alien species and active management is required to reduce impact and prevent spread in both horticulture and natural ecosystems. Conversely, there are regions thought to be suitable for the pathogen where no disease is observed. We developed a climex model for the global distribution of P. cinnamomi based on the pathogen's response to temperature and moisture and by incorporating extensive empirical evidence on the presence and absence of the pathogen. The climex model captured areas of climatic suitability where P. cinnamomi occurs that is congruent with all available records. The model was validated by the collection of soil samples from asymptomatic vegetation in areas projected to be suitable by the model for which there were few records. DNA was extracted, and the presence or absence of P. cinnamomi was determined by high-throughput sequencing (HTS). While not detected using traditional isolation methods, HTS detected P. cinnamomi at higher elevations in eastern Australia and central Tasmania as projected by the climex model. Further support for the climex model was obtained using the large data set from south-west Australia where the proportion of positive records in an area is related to the Ecoclimatic Index value for the same area. We provide for the first time a comprehensive global map of the current P. cinnamomi distribution, an improved climex model of the distribution, and a projection to 2080 of the distribution with predicted climate change. This information provides the basis for more detailed regional-scale modelling and supports risk assessment for governments to plan management of this important soil-borne plant pathogen
Distribution and diversity of Phytophthora across Australia
The introduction and subsequent impact of Phytophthora cinnamomi within native vegetation is one of the major conservation issues for biodiversity in Australia. Recently, many new Phytophthora species have been described from Australia's native ecosystems; however, their distribution, origin, and potential impact remain unknown. Historical bias in Phytophthora detection has been towards sites showing symptoms of disease, and traditional isolation methods show variable effectiveness of detecting different Phytophthora species. However, we now have at our disposal new techniques based on the sampling of environmental DNA and metabarcoding through the use of high-throughput sequencing. Here, we report on the diversity and distribution of Phytophthora in Australia using metabarcoding of 640 soil samples and we compare the diversity detected using this technique with that available in curated databases. Phytophthora was detected in 65% of sites, and phylogenetic analysis revealed 68 distinct Phytophthora phylotypes. Of these, 21 were identified as potentially unique taxa and 25 were new detections in natural areas and/or new introductions to Australia. There are 66Phytophthora taxa listed in Australian databases, 43 of which were also detected in this metabarcoding study. This study revealed high Phytophthora richness within native vegetation and the additional records provide a valuable baseline resource for future studies. Many of the Phytophthora species now uncovered in Australia's native ecosystems are newly described and until more is known we need to be cautious with regard to the spread and conservation management of these new species in Australia's unique ecosystems
Legitimizing intimate partner violence: the role of romantic love and the mediating effect of patriarchal ideologies
Romantic love in heterosexual relationships is recognized as an important aspect to be considered in relation to the psychosocial mechanisms associated with the persistence of intimate partner violence and the help-seeking barriers faced by female victims. However, few studies have explored the processes underlying the relationship between this form of love and attitudes toward this kind of violence. To do this, the current study aims to analyze the relationship between the adherence to romantic love and the legitimization of intimate partner violence (i.e., perceived severity of violence, victim blame, and exoneration of the perpetrator). It was also to test the mediating effect of patriarchal ideologies (i.e., ambivalent sexism and domestic violence myths) on this relationship. Two hundred thirty-five French adults (51.1% women) were surveyed. The data were analyzed with structural equation models to study the mediations between the variables considered. Consistent with our hypotheses, the results showed that the more the participants adhered to romantic love, the more they blamed the victim and exonerated the perpetrator. They also showed a positive link between romantic love, ambivalent sexism, and domestic violence myths. Finally, the results demonstrated that the relationship between romantic love and the legitimization of violence is mediatized by ambivalent sexism and domestic violence myths. The findings illustrate the need to deconstruct romantic love ideology and the psychosocial logics underlying the legitimization of intimate partner violence.info:eu-repo/semantics/publishedVersio
“I h 8 u”: Findings from a five-year study of text and e-mail bullying
Copyright @ 2010 British Educational Research Association. The final version of this article is available at the link below.This study charts reports of nasty or threatening text and e-mail messages received by students in academic years 7 and 8 (11-13 years of age) attending 13 secondary schools in the North of England between 2002-2006. Annual surveys were undertaken on behalf of the local education authority (LEA) to monitor bullying. Results indicated that, over five years, the number of pupils receiving one or more nasty or threatening text messages or e-mails increased significantly, particularly among girls. However, receipt of frequent nasty or threatening text and e-mail messages remained relatively stable. For boys, being a victim of direct-physical bullying was associated with receiving nasty or threatening text and e-mail messages; for girls it was being unpopular among peers. Boys received more hate-related messages and girls were primarily the victims of name-calling, Findings are discussed with respect to theoretical and policy developments, and recommendations for future research are offered
Maximal rates of excretion and synthesis of urea in normal and cirrhotic subjects.
A B S T R A C T When normal individuals eat 0.33 g protein N/kg body weight (BW)3' per day, they excrete 10-15 mg urea N/h per kg BW3'4. If they now ingest (at 0 h) 0.27 (dose A), 0.40 (dose B), 0.53 (dose C), 0.94 (dose D), or 1.33 (dose E) g protein N/kg BW3' (in the form of casein, ovalbumin, or lactalbumin), the rate of urea N excretion accelerates within 4 h. At dose C a maximal rate of urinary urea N excretion (MRUE) is reached, which averages 55 mg urea N/h per kg BW3' and which persists for 16 h. Higher doses of protein do not further accelerate urea excretion, but prolong the duration of MRUE to 28 h (after dose E). Blood urea N (BUN) rises by These findings indicate that MRUE corresponds to a period of maximal rate of urea synthesis (MRUS). MRUS is greater than MRUE because one fraction of newly formed urea is hydrolyzed in the gastrointestinal tract, and another fraction may accumulate temporarily in body water during the MRUE period. Oral neomycin reduces the proportion of urea hydrolyzed in the gut to less than 20%; its extent is measured by recovery in the urine of a tracer dose of ["4C]urea injected intramuscularly during determination of MRUE. Accumulation of urea in body water is estimated from increment in BUN during the period of MRUE measurement (8-24 h after dose E of casein) and from body wate
GH peak response to GHRH-arginine: relationship to insulin resistance and other cardiovascular risk factors in a population of adults aged 50–90
OBJECTIVE: To assess the GH response to GHRH-arginine in apparently healthy adults in relation to cardiovascular risk factors. DESIGN: Cross-sectional. PATIENTS: Eighty-six male and female volunteers aged 50–90. MEASUREMENTS: GH peak response to GHRH-arginine and cardiovascular risk factors, including obesity, insulin resistance, low levels of high density lipoprotein (HDL) cholesterol, elevated triglycerides, and hypertension. The primary outcome measurement was GH response to GHRH-arginine. The relationship between GH peak responses and cardiovascular risk factors was determined after data collection. RESULTS: GH peaks were highly variable, ranging from 2·3 to 185 µg/l (14% with GH peaks < 9 µg/l). An increasing number of cardiovascular risk factors were associated with a lower mean GH peak (P < 0·0001). By univariate analysis, fasting glucose, insulin, body mass index (BMI), HDL cholesterol and triglycerides were significantly associated with GH peak (all P < 0·0001). Multiple regression analysis revealed that fasting glucose, fasting insulin, BMI, triglycerides and sex accounted for 54% of GH peak variability. The role of abdominal fat as it relates to GH peak was explored in a subset of 45 subjects. Trunk fat and abdominal subregion fat measured by dual energy X-ray absorptiometry (DXA) were inversely related to GH peak (P < 0·008 and 0·001, respectively). Analysis of this subgroup by multiple regression revealed that subregion abdominal fat became the significant obesity-related determinant of GH peak, but still lagged behind fasting insulin and glucose. CONCLUSIONS: GH response to secretagogues was highly variable in apparently healthy adults aged 50–90 years. Peak GH was significantly related to fasting glucose, insulin, BMI, HDL cholesterol, triglycerides, trunk fat and abdominal subregion fat, with fasting glucose ranking first by multiple regression analysis. There was a strong relationship between cardiovascular risk factors and low GH, with individual risk factors being additive. Although these data do not differentiate between low GH being a cause or an effect of these cardiovascular risk factors, they indicate that the relationship between low GH and increased cardiovascular risk may be physiologically important in the absence of pituitary disease
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