7,339 research outputs found
Chemiluminescence of asbestos-activated macrophages
Chemiluminescence, a measure of reactive oxygen release by phagocytes, was compared in peritoneal exudate macrophages elicited with chrysotile asbestos, Corynebacterium parvum and saline. Chrysotile asbestos- and C. parvum-activated macrophages produced significantly more chemiluminescence than saline-elicited macrophages. In a second series of experiments the ability of opsonized chrysotile asbestos to act as a trigger for the release of chemiluminescence was tested. Opsonized chrysotile asbestos produced a dose-related release of chemiluminescence from activated macrophages except at the highest dose where chemiluminescence was reduced due, possibly, to a toxic effect of chrysotile during the assay. Opsonized latex also triggered a dose-related chemiluminescent response from activated macrophages. The potential role of toxic reactive oxygen species, released from macrophages, in the development of asbestos-related pulmonary inflammation and fibrosis are discussed
Contextual perception under active inference
Human social interactions depend on the ability to resolve uncertainty about the mental states of others. The context in which social interactions take place is crucial for mental state attribution as sensory inputs may be perceived differently depending on the context. In this paper, we introduce a mental state attribution task where a target-face with either an ambiguous or an unambiguous emotion is embedded in different social contexts. The social context is determined by the emotions conveyed by other faces in the scene. This task involves mental state attribution to a target-face (either happy or sad) depending on the social context. Using active inference models, we provide a proof of concept that an agentâs perception of sensory stimuli may be altered by social context. We show with simulations that context congruency and facial expression coherency improve behavioural performance in terms of decision times. Furthermore, we show through simulations that the abnormal viewing strategies employed by patients with schizophrenia may be due to (i) an imbalance between the precisions of local and global features in the scene and (ii) a failure to modulate the sensory precision to contextualise emotions
Antitumour responses induced by short-term pretreatment with tumour cells.
The injection (s.c. or i.p.) of 10(6) live or lethally irradiated methylcholanthrene-induced fibrosarcoma cells into CBA/Ca mice one or 2 days before i.v. challenge with the same tumour inhibited the formation of artificial lung tumour metastases. In addition, it also frequently enhanced the cytostatic effect of peritoneal exudate cells on monolayers of the same tumour. The effects on lung tumour metastasis were not noted if X-irradiated tumour was injected i.v., or if s.c. administration was delayed until one day after i.v. challenge. Similar effects on tumour growth were also observed in C3Hf/Bu mice and (CBA/Ca x A/HeJ) F1 hybrids which were pretreated (s.c.) with tumour shortly before i.v. challenge with the same tumour. Further studies in CBA/Ca mice suggested that the protective effect was tumour-specific, for the growth of i.v. injected tumour was not significantly inhibited by pretreatement with a number of other MC-induced or spontaneous tumours from the same and different strains
Modelling the resilience of forage crop production to future climate change in the dairy regions of southeastern Australia using APSIM
A warmer and potentially drier future climate is likely to influence the production of forage crops on dairy farms in The southeast dairy regions of Australia. Biophysical modelling was undertaken to explore the resilience of forage production of individual forage crops to scalar increases in temperature, atmospheric carbon dioxide (CO2) concentration and changes in daily rainfall. The model APSIM was adapted to reflect species specific responses to growth under elevated atmospheric CO2 concentrations. It was then used to simulate 40 years of production of forage wheat, oats, annual ryegrass, maize grown for silage, forage sorghum, forage rape and alfalfa grown at three locations in southeast Australia with increased temperature scenarios (1, 2, 3 and 4 °C of warming) and atmospheric CO2 concentration (435, 535, 640 and 750 ppm) and decreasing rainfall scenarios (10, 20 or 30% less rainfall). At all locations positive increases in DM yield compared with the baseline climate scenario were predicted for lucerne (2·6â93·2% increase), wheat (8·9-37·4% increase), oats (6·1â35·9% increase) and annual ryegrass (9·7â66·7% increase) under all future climate scenarios. The response of forage rape and forage sorghum varied between location and climate change scenario. At all locations, maize was predicted to have a minimal change in yield under all future climates (between a 2·6% increase and a 6·8% decrease). The future climate scenarios altered the seasonal pattern of forage supply for wheat, oats and lucerne with an increase in forage produced during winter. The resilience of forage crops to climate change indicates that they will continue to be an important component of dairy forage production in southeastern Australia
Anti-Tumour Effect In Vitro of Lymphocytes and Macrophages from Mice Treated with Corynebacterium Parvum
Cells from the spleen, lymph node, peripheral blood and peritoneal exudate of mice treated with C. parvum were tested for their ability to inhibit tumour growth in vitro. The peritoneal exudate cells from C. parvum treated mice were extremely effective in inhibiting tumour growth whereas the spleen and peripheral blood cells were only moderately so. In contrast, the lymph node cells caused only a modest inhibition of tumour growth at a very high effector to target cell ratio. Spleen cells from normal mice also exerted a moderate anti-tumour effect
GoSam: A program for automated one-loop Calculations
The program package GoSam is presented which aims at the automated
calculation of one-loop amplitudes for multi-particle processes. The amplitudes
are generated in terms of Feynman diagrams and can be reduced using either
D-dimensional integrand-level decomposition or tensor reduction, or a
combination of both. GoSam can be used to calculate one-loop corrections to
both QCD and electroweak theory, and model files for theories Beyond the
Standard Model can be linked as well. A standard interface to programs
calculating real radiation is also included. The flexibility of the program is
demonstrated by various examples.Comment: 10 pages, Talk given at the International Workshop on Advanced
Computing and Analysis Techniques in Physics Research (ACAT), Uxbridge,
London, September 201
âIt Relates to My Everyday Life.â Critical Pedagogy and Student Explanations of Interest in Sociology Course Topics
We applied critical pedagogy in the college classroom by asking students what topics they would want covered in their Introduction to Sociology courses if they were given the power to decide. Students were also asked to explain why they were interested, and uninterested, in learning about the topics they chose from our questionnaire. Survey data was collected from 191 students at a southeastern community college; the majority were not sociology majors. Overall, students were the most interested in learning about culture, deviance, race, and gender issues. Students were the least interested in learning about topics concerning urbanization and the economy. We found that students are typically interested in topics that are related to general curiosities or are applicable to the studentsâ personal lives or future careers. However, students were vaguer in their responses regarding why they were uninterested in learning about particular sociological topics; most students claimed that they were simply âjust uninterested.â These results support the claim that a studentâs desire to learn material is guided by how personally invested he or she is in the topic. By implementing a critical pedagogical teaching approach in the classroom, professors could increase student interest, thus fostering more successful and satisfied students
Use of the short-term inflammatory response in the mouse peritoneal cavity to assess the biological activity of leached vitreous fibers.
We used a special-purpose glass microfiber sample, Johns-Manville Code 100/475, to study the effects of various acid and alkali treatments on biological activity as assessed by inflammation in the mouse peritoneal cavity, the leaching of Si, and the phase contrast optical microscopy (PCOM) fiber number. We used mild and medium treatments with oxalic acid and Tris buffer and harsh treatment with concentrated HCl and NaOH. Mild oxalic acid and Tris treatment for 2 weeks had no effect on any of the end-points, but prolonging the mild oxalic acid treatment time to 2 months reduced the biological activity and the fiber number. Medium oxalic acid treatment reduced the biological activity and the fiber number and caused a loss of Si. Medium Tris alkali treatment reduced the PCOM-countable fibers and the biological activity but did not cause a substantial loss of Si. Harsh treatment with strong HCl did not affect the fiber number or cause leaching but the biological activity was reduced; strong NaOH reduced the fiber number and biological activity, and caused marked leaching of Si. The medium oxalic acid conditions (pH 1.4) were more acid than those found in lung cells but produced the same effects (reduction in fiber number and biological activity) as the more physiological mild treatment (pH 4.0), when prolonged. This study suggests that medium oxalic acid treatment can be used as a short-term assay to compare loss of Si, reduction in fiber number, and change in biological activity of vitreous fibers.(ABSTRACT TRUNCATED AT 250 WORDS
The development of a new accountability measurement framework and tool for global health initiatives
The Global Strategy for Women's Children's and Adolescents' Health emphasizes accountability as essential to ensure that decision-makers have the information required to meet the health needs of their populations and stresses the importance of tracking resources, results, and rights to see 'what works, what needs improvement and what requires increased attention'. However, results from accountability initiatives are mixed and there is a lack of broadly applicable, validated tools for planning, monitoring and evaluating accountability interventions. This article documents an effort to transform accountability markers-including political will, leadership and the monitor-review-act cycle-into a measurement tool that can be used prospectively or retrospectively to plan, monitor and evaluate accountability initiatives. It describes the development process behind the tool including the literature review, framework development and subsequent building of the measurement tool itself. It also examines feedback on the tool from a panel of global experts and the results of a pilot test conducted in Bauchi and Gombe states in Nigeria. The results demonstrate that the tool is an effective aid for accountability initiatives to reflect on their own progress and provides a useful structure for future planning, monitoring and evaluation. The tool can be applied and adapted to other accountability mechanisms working in global health
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