999 research outputs found
Barbaetis: A New Genus of Eastern Nearctic Mayflies (Ephemeroptera: Baetidae)
The new genus Barbaetis Waltz and McCafferty, and new species Barbaetis benfieldi Kennedy are described from larvae collected from the New River, Virginia. Barbaetis is easily told from Baetis by the presence of procoxal osmobranchia. Cladistics of B. benfieldi, related Pseudocloeon species, and the lutheri and pavidus complexes of Baetis are presented and indicate the need for further taxonomic revision. The habitat of B. benfieldi is described in terms of several ecological parameters. The new species demonstrates a univoltine life history with postembryonic development restricted to a short springtime period
Thermal Imaging to Study Stress Non-invasively in Unrestrained Birds.
Stress, a central concept in biology, describes a suite of emergency responses to challenges. Among other responses, stress leads to a change in blood flow that results in a net influx of blood to key organs and an increase in core temperature. This stress-induced hyperthermia is used to assess stress. However, measuring core temperature is invasive. As blood flow is redirected to the core, the periphery of the body can cool. This paper describes a protocol where peripheral body temperature is measured non-invasively in wild blue tits (Cyanistes caeruleus) using infrared thermography. In the field we created a set-up bringing the birds to an ideal position in front of the camera by using a baited box. The camera takes a short thermal video recording of the undisturbed bird before applying a mild stressor (closing the box and therefore capturing the bird), and the bird's response to being trapped is recorded. The bare skin of the eye-region is the warmest area in the image. This allows an automated extraction of the maximum eye-region temperature from each image frame, followed by further steps of manual data filtering removing the most common sources of errors (motion blur, blinking). This protocol provides a time series of eye-region temperature with a fine temporal resolution that allows us to study the dynamics of the stress response non-invasively. Further work needs to demonstrate the usefulness of the method to assess stress, for instance to investigate whether eye-region temperature response is proportional to the strength of the stressor. If this can be confirmed, it will provide a valuable alternative method of stress assessment in animals and will be useful to a wide range of researchers from ecologists, conservation biologists, physiologists to animal welfare researchers
Bridging Teacher Candidates, School Communities, and the World During a Pandemic
The Covid-19 pandemic caused distance that separated the teacher from the learner as schools and higher education moved to virtual and flexible learning communities. Likewise, at the same time racial tensions were growing further increasing the distance and divide across the country. This positions teacher educators with the responsibility to bridge this distance.
The challenges of preparing educators for activism in a post-Covid educational context that considers cultural literacy, ethical leadership, and community engagement is explored with three narratives. These narratives provide the opportunity to think with and through our commitments in early childhood and elementary teacher education. Collectively, these narratives use the conditions of learning and teaching in a pandemic to consider educational challenges of the past and the things we must do to create a more equitable and just future. We conclude this essay with essential commitments as we work to bridge the distance and build community.
Classification: Reflective Essa
Where will we live when we get older?
Ageing populations, although exhibiting marked differences across countries and cultures, are a global phenomenon. Old-age dependency ratios in most developed countries are projected to double by the year 2050. In Australia there will be a strain on economic growth as a large part of the population moves from pre-retirement to post-retirement age over the next 25 years. A disproportionate amount of this strain will be concentrated in aged-care housing or retirement accommodation. Current evidence suggests that existing housing stock for older people is inadequate. As the Australian population ages, the maintenance and long-term performance of retirement housing is a key concern of government and housing providers. This study looked at four aged-care or retirement providers across Australia and examined the performance of the current housing stock managed by these providers. The interviews revealed that housing design decisions in retirement stock, although critically important to the changing needs of occupants and the adequate supply of suitable housing, are often ill-considered. The findings critically question the idea of simply building ‘more of the same’ to relieve demand. This study has major implications for the future of Australian retirement housing, especially as the population ages dramatically.<br /
Quaternary ferrites by batch and continuous flow hydrothermal synthesis: a comparison
Crystalline spinel quaternary ferrites MxZn1−xFe2O4 (M = Co, Ni; x = 0.2, 0.35, 0.5, 0.65, 0.8) were synthesised through conventional batch hydrothermal synthesis (HT) at 135 °C as well as via continuous flow hydrothermal synthesis (CHFS). The as prepared compounds were thoroughly characterised from a compositional (ICP-MS, XPS) and structural (XRD) point of view in order to compare the synthetic approaches and achieve a greater understanding of how the chosen approach influences the characteristics of the resulting spinel
A simple vector system to improve performance and utilisation of recombinant antibodies
BACKGROUND: Isolation of recombinant antibody fragments from antibody libraries is well established using technologies such as phage display. Phage display vectors are ideal for efficient display of antibody fragments on the surface of bacteriophage particles. However, they are often inefficient for expression of soluble antibody fragments, and sub-cloning of selected antibody populations into dedicated soluble antibody fragment expression vectors can enhance expression. RESULTS: We have developed a simple vector system for expression, dimerisation and detection of recombinant antibody fragments in the form of single chain Fvs (scFvs). Expression is driven by the T7 RNA polymerase promoter in conjunction with the inducible lysogen strain BL21 (DE3). The system is compatible with a simple auto-induction culture system for scFv production. As an alternative to periplasmic expression, expression directly in the cytoplasm of a mutant strain with a more oxidising cytoplasmic environment (Origami 2™ (DE3)) was investigated and found to be inferior to periplasmic expression in BL21 (DE3) cells. The effect on yield and binding activity of fusing scFvs to the N terminus of maltose binding protein (a solubility enhancing partner), bacterial alkaline phosphatase (a naturally dimeric enzymatic reporter molecule), or the addition of a free C-terminal cysteine was determined. Fusion of scFvs to the N-terminus of maltose binding protein increased scFv yield but binding activity of the scFv was compromised. In contrast, fusion to the N-terminus of bacterial alkaline phosphatase led to an improved performance. Alkaline phosphatase provides a convenient tag allowing direct enzymatic detection of scFv fusions within crude extracts without the need for secondary reagents. Alkaline phosphatase also drives dimerisation of the scFv leading to an improvement in performance compared to monovalent constructs. This is illustrated by ELISA, western blot and immunohistochemistry. CONCLUSION: Nine scFv expression vectors have been generated and tested. Three vectors showed utility for expression of functional scFv fragments. One vector, pSANG14-3F, produces scFv-alkaline phosphatase fusion molecules which offers a simple, convenient and sensitive way of determining the reactivity of recombinant antibody fragments in a variety of common assay systems
Thinking beyond the hybrid:“actually-existing” cities “after neoliberalism” in Boyle <i>et al.</i>
In their article, ‘The spatialities of actually existing neoliberalism in Glasgow, 1977 to present’, Mark Boyle, Christopher McWilliams and Gareth Rice (2008) usefully problematise our current understanding of neoliberal urbanism. Our response is aimed at developing a sympathetic but critical approach to Boyle et al's understanding of neoliberal urbanism as illustrated by the Glasgow example. In particular, the counterposing by Boyle et al of a 'hybrid, mutant' model to a 'pure' model of neoliberalism for us misrepresents existing models of neoliberalism as a perfectly finished object rather than a roughly mottled process. That they do not identify any ‘pure’ model leads them to create a straw construct against which they can claim a more sophisticated, refined approach to the messiness of neoliberal urbanism. In contrast, we view neoliberalism as a contested and unstable response to accumulation crises at various scales of analysis
Managing healthcare budgets in times of austerity: the role of program budgeting and marginal analysis
Given limited resources, priority setting or choice making will remain a reality at all levels of publicly funded healthcare across countries for many years to come. The pressures may well be even more acute as the impact of the economic crisis of 2008 continues to play out but, even as economies begin to turn around, resources within healthcare will be limited, thus some form of rationing will be required. Over the last few decades, research on healthcare priority setting has focused on methods of implementation as well as on the development of approaches related to fairness and legitimacy and on more technical aspects of decision making including the use of multi-criteria decision analysis. Recently, research has led to better understanding of evaluating priority setting activity including defining ‘success’ and articulating key elements for high performance. This body of research, however, often goes untapped by those charged with making challenging decisions and as such, in line with prevailing public sector incentives, decisions are often reliant on historical allocation patterns and/or political negotiation. These archaic and ineffective approaches not only lead to poor decisions in terms of value for money but further do not reflect basic ethical conditions that can lead to fairness in the decision-making process. The purpose of this paper is to outline a comprehensive approach to priority setting and resource allocation that has been used in different contexts across countries. This will provide decision makers with a single point of access for a basic understanding of relevant tools when faced with having to make difficult decisions about what healthcare services to fund and what not to fund. The paper also addresses several key issues related to priority setting including how health technology assessments can be used, how performance can be improved at a practical level, and what ongoing resource management practice should look like. In terms of future research, one of the most important areas of priority setting that needs further attention is how best to engage public members
Expression of a barley cystatin gene in maize enhances resistance against phytophagous mites by altering their cysteine-proteases
Phytocystatins are inhibitors of cysteine-proteases from plants putatively involved in plant defence based on their capability of inhibit heterologous enzymes. We have previously characterised the whole cystatin gene family members from barley (HvCPI-1 to HvCPI-13). The aim of this study was to assess the effects of barley cystatins on two phytophagous spider mites, Tetranychus urticae and Brevipalpus chilensis. The determination of proteolytic activity profile in both mite species showed the presence of the cysteine-proteases, putative targets of cystatins, among other enzymatic activities. All barley cystatins, except HvCPI-1 and HvCPI-7, inhibited in vitro mite cathepsin L- and/or cathepsin B-like activities, HvCPI-6 being the strongest inhibitor for both mite species. Transgenic maize plants expressing HvCPI-6 protein were generated and the functional integrity of the cystatin transgene was confirmed by in vitro inhibitory effect observed against T. urticae and B. chilensis protein extracts. Feeding experiments impaired on transgenic lines performed with T. urticae impaired mite development and reproductive performance. Besides, a significant reduction of cathepsin L-like and/or cathepsin B-like activities was observed when the spider mite fed on maize plants expressing HvCPI-6 cystatin. These findings reveal the potential of barley cystatins as acaricide proteins to protect plants against two important mite pests
Emperor penguin body surfaces cool below air temperature
Emperor penguins Aptenodytes forsteri are able to survive the harsh Antarctic climate because of specialized anatomical, physiological and behavioural adaptations for minimizing heat loss. Heat transfer theory predicts that metabolic heat loss in this species will mostly depend on radiative and convective cooling. To examine this, thermal imaging of emperor penguins was undertaken at the breeding colony of Pointe Géologie in Terre Adélie (668400 S 1408 010 E), Antarctica in June 2008. During clear sky conditions, most outer surfaces of the body were colder than surrounding sub-zero air owing to radiative cooling. In these conditions, the feather surface will paradoxically gain heat by convection from surrounding air. However, owing to the low thermal conductivity of plumage any heat transfer to the skin surface will be negligible. Future thermal imaging studies are likely to yield further insights into the adaptations of this species to the Antarctic climate
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