5,149 research outputs found

    Establishing death in stranded Odontocetes (toothed whales) using other mammals : a pilot study : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Zoology at Massey University

    Get PDF
    The aim of this study was to investigate and evaluate a new method for determining death in stranded odontocetes (toothed whales). The new method was using the pulsations seen in the retinal blood vessels in the place of the heart rate. The retinal blood vessels can visualized, using an ophthalmoscope, in the fundus of the eye. Initially the procedure was to be testing using animals at a mass stranding, but there were no suitable strandings that took place during the time of the study. Therefore other mammal species were used to test the procedure. These mammals were cattle, sheep, and dogs, with additional observational testing carried out on seals, sea lions and dolphins. The mammals were chosen because of their availability and supply. The results showed that there was a strong relationship between the heart rate and the pulsations measured in the retinal blood vessels. This was expected as the cardiovascular system is connected and pulsations of blood vessels must have originated from the heart. The results using dogs, also indicated that there is a relationship between the cessation of the pulsations in the retinal blood vessels and the cessation of the heart beat. Dogs were used as a benchmark by which all other mammals could be compared. Therefore this study indicates that it is possible to identify the cessation of the heart using the cessation of the pulsations in the retinal blood vessels

    Evaluation of Toxicity Analysis for Foundry Sand Specifications

    Get PDF
    Byproducts from many industries have the potential to be used as construction materials, but some means is required to determine if the material is environmentally benign. Foundry sands are produced in many states and can be useful as in transportation projects. However, INDOT currently requires the use of the MICROTOX test to assess the potential toxicity of the sands, and this requirement is viewed as an unnecessary impediment by the producers of foundry sands and is a requirement not encountered in other states. Therefore, the goal of this project was to review current requirements for testing of recycled materials, determine the availability of MICROTOX testing, and to make recommendations concerning the continued use of MICROTOX as an assessment tool. Strictly from viewpoint of environmental protection, the inclusion of Microtox makes sense. The test has the sensitivity to detect potentially toxic agents in recycled sand that might escape chemical analysis. The test, therefore, provides a layer of assurance that otherwise would be absent. From the perspective of the foundry industry, the Microtox test is an unneeded hurdle that could potentially block the beneficial use of spent foundry sand. Cost is one consideration, but the lack of local analytical facilities for the Microtox is particularly troublesome. Our recommendation is that the Microtox test be retained by INDOT, but we suggest the following: a) Minimize the number of samples of foundry sand that must be tested possibly by reducing the frequency of sampling and testing. b) A consistent, readily available laboratory needs to be established to ensure rapid turn around of analyses and reduced costs. Currently, the demand is low and some dedicated equipment is needed to perform the test. One of the potential outcomes of this project discussed during the negotiations for this project was a possible follow-up project in which we would investigate the modifications to the bioassay. This might include exploring alternatives to Microtox or simplifications of the Microtox test. We remain open to this possibility, but from the scientific point of view, such a follow-up may not be necessary. Of all the bioassays we reviewed, Microtox seemed to be the most widely used (though not for foundry sands), and we found no evidence that other bioassays were being offered routinely at commercial labs

    Autonomous analysis to identify bijels from two-dimensional images

    Get PDF
    Bicontinuous interfacially jammed emulsion gels (bijels) are novel composite materials that can be challenging to manufacture. As a step towards automating production, we have developed a machine learning tool to classify fabrication attempts. We use training and testing data in the form of confocal images from both successful and unsuccessful attempts at bijel fabrication. We then apply machine learning techniques to this data in order to classify whether an image is a bijel or a non-bijel. Our principal approach is to process the images to find their autocorrelation function and structure factor, and from these functions we identify variables that can be used for training a supervised machine learning model to identify a bijel image. We are able to categorise images with reasonable accuracies of 85.4% and 87.5% for two different approaches. We find that using both the liquid and particle channels helps to achieve optimal performance and that successful classification relies on the bijel samples sharing a characteristic length scale. Our second approach is to classify the shapes of the liquid domains directly; the shape descriptors are then used to classify fabrication attempts via a decision tree. We have used an adaptive design approach to find an image pre-processing step that yields the optimal classification results. Again, we find that the characteristic length scale of the images is crucial in performing the classification

    Methanogenic \u3cem\u3eArchaea\u3c/em\u3e and human periodontal disease

    Get PDF
    Archaea have been isolated from the human colon, vagina, and oral cavity, but have not been established as causes of human disease. In this study, we reveal a relationship between the severity of periodontal disease and the relative abundance of archaeal small subunit ribosomal RNA genes (SSU rDNA) in the subgingival crevice by using quantitative PCR. Furthermore, the relative abundance of archaeal small subunit rDNA decreased at treated sites in association with clinical improvement. Archaea were harbored by 36% of periodontitis patients and were restricted to subgingival sites with periodontal disease. The presence of archaeal cells at these sites was confirmed by fluorescent in situ hybridization. The archaeal community at diseased sites was dominated by a Methanobrevibacter oralis-like phylotype and a distinct Methanobrevibacter subpopulation related to archaea that inhabit the gut of numerous animals. We hypothesize that methanogens participate in syntrophic relationships in the subgingival crevice that promote colonization by secondary fermenters during periodontitis. Because they are potential alternative syntrophic partners, our finding of larger Treponema populations sites without archaea provides further support for this hypothesis

    Radicalisation of Young Adults in the Balkan States: Counter-Measures, Healthcare Provision, and Community Involvement

    Get PDF
    Decreasing the rise of extremism remains a priority for governments worldwide.  Motives behind joining an extremist organisation are complex and often unique to the individual, making prevention strategies difficult to design and implement.  This article explores several facets of this complex problem, particularly in relation to young adults, including links between extremism, criminality and incarceration, mental health, socioeconomic status and the rise of radicalisation ‘hotspots’ in Muslim majority states in the Western Balkans, where lack of government leadership allows extremist organisations to flourish.  Potential counter radicalisation measures are also discussed in various contexts, including healthcare systems, the community, internationally and within the Balkan region

    Time and location differentiated NOX control in competitive electricity markets using cap-and-trade mechanisms

    Get PDF
    Due to variations in weather and atmospheric chemistry, the timing and location of nitrogen oxide (NOX) reductions determine their effectiveness in reducing ground-level ozone, which adversely impacts human health. Electric generating plants are the primary stationary sources of NOX in most regions of the United States. In the Eastern U.S. they are subject to a summertime NOX cap and trade program that is not well matched to the time and locational impacts of NOX on ozone formation. We hypothesize that the integration of weather and atmospheric chemistry forecasting, a cap and trade system in which the "exchange rates" for permits can be varied by time and location based on these forecasts, and its application to a competitive wholesale electricity market, can achieve ozone standards more efficiently. To demonstrate the potential for reductions in NOX emissions in the short run, we simulate the magnitude of NOX reductions that can be achieved at various locations and times as a consequence of redispatch of generating units in the "classic" PJM region taking supply-demand balance constraints and network congestion into account. We report simulations using both a zonal model and an optimal power flow model.(cont.) We also estimate the relationship between the level NOX emission prices, competitive market responses to different levels of NOX prices, and the associated reductions in NOx emissions. The estimated maximum potential reductions, which occur at NOX prices of about $125,000/ton, are about 8 tons (20%) hourly in peak electricity demand hours and about 10 tons (50%) in average demand hours. We find that network constraints have little effect on the magnitude of the reductions in NOX emissions.Funding provided jointly by the U.S. Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA); as well as the CEEP

    Rethinking the Baseline in Diversity Research: Should We Be Explaining the Effects of Homogeneity?

    Get PDF
    It is often surprisingly difficult to make definitive scientific statements about the functional value of group diversity. We suggest that one clear pattern in the group diversity literature is the prevailing convention of interpreting outcomes as the effect of diversity alone. Although work in this arena typically compares diverse groups with homogeneous ones, we most often conceive of homogeneous groups as a baseline—a reference point from which we can understand how diversity has changed behavior or what type of response is “normal.” In this article, we offer a new perspective through a focus on two propositions. The first proposition is that homogeneity has independent effects of its own—effects that, in some cases, are robust in comparison with the effects of diversity. The second proposition is that even though subjective responses in homogeneous groups are often treated as a neutral indicator of how people would ideally respond in a group setting, evidence suggests that these responses are often less objective or accurate than responses in diverse groups. Overall, we believe that diversity research may unwittingly reveal important insights regarding the effects of homogeneity.National Science Foundation (U.S.) (NSF Grant 0921728

    Skin temperature reveals the intensity of acute stress

    Get PDF
    Acute stress triggers peripheral vasoconstriction, causing a rapid, short-term drop in skin temperature in homeotherms. We tested, for the first time, whether this response has the potential to quantify stress, by exhibiting proportionality with stressor intensity. We used established behavioural and hormonal markers: activity level and corticosterone level, to validate a mild and more severe form of an acute restraint stressor in hens (Gallus gallus domesticus). We then used infrared thermography (IRT) to non-invasively collect continuous temperature measurements following exposure to these two intensities of acute handling stress. In the comb and wattle, two skin regions with a known thermoregulatory role, stressor intensity predicted the extent of initial skin cooling, and also the occurrence of a more delayed skin warming, providing two opportunities to quantify stress. With the present, cost-effective availability of IRT technology, this non-invasive and continuous method of stress assessment in unrestrained animals has the potential to become common practice in pure and applied research

    Particle-stabilized water droplets that sprout millimeter-scale tubes

    Get PDF
    A layer of colloidal particles will become irreversibly trapped at a fluid–fluid interface if they exhibit partial wettability with both fluid phases. This effect has been exploited to create Pickering emulsions, armored bubbles, and new materials of various kinds. When the interfaces are densely coated with particles, they behave like rigid elastic sheets with moduli that are proportional to the underlying interfacial tension. The interfaces are permeable, a characteristic that can, for example, lead to compositional ripening of Pickering emulsions Here we show that when particle-stabilized water droplets are created in a bath of toluene with ethanol, millimeter-scale tubes are observed to sprout from the top of the droplets. Growth is driven by the ethanol partitioning from the toluene into the water which leads to an internal overpressure. Vertical growth occurs over many minutes; finally the tube buckles when it can no longer support its own weight (Figure 1). There are several different growth modes controlled by the concentration of ethanol and of silica particles.[1] An alternative way to manipulate the system is by using a different alcohol, leading to insight on the role of the underlying three-fluid phase diagram. Our work paves the way for future studies of droplet growth because the liquid droplets and the interfacial properties can be independently studied. Please click Additional Files below to see the full abstract
    corecore