438 research outputs found
Food neophobia and mealtime food consumption in 4-5 year old children.
Background: Previous research has documented a negative association between maternal report
of child food neophobia and reported frequency of consumption of fruit, vegetables, and meat. This
study aimed to establish whether neophobia is associated with lower intake of these food types in
naturalistic mealtime situations.
Methods: One hundred and nine parents of 4ā5 year olds completed questionnaires which
included a six-item version of the Child Food Neophobia Scale (CFNS). The children took part in
a series of 3 test lunch meals at weekly intervals at school at which they were presented with:
chicken, cheese, bread, cheese crackers, chocolate biscuits, grapes and tomatoes or carrot sticks.
Food items served to each child were weighed before and after the meal to assess total intake of
items in four categories: Fruit and vegetables, Protein foods, Starchy foods and Snack foods.
Pearson Product Moment Correlations and independent t tests were performed to examine
associations between scores on the CFNS and consumption during lunches.
Results: Neophobia was associated with lower consumption of fruit and vegetables, protein foods
and total calories, but there was no association with intake of starch or snack foods.
Conclusion: These results support previous research that has suggested that neophobia impacts
differentially on consumption of different food types. Specifically it appears that children who score
highly on the CFNS eat less fruit, vegetables and protein foods than their less neophobic peers.
Attempts to increase intake of fruit, vegetables and protein might usefully incorporate strategies
known to reduce the neophobic response
The Parallel Worm Tracker: A Platform for Measuring Average Speed and Drug-Induced Paralysis in Nematodes
Background
Caenorhabditis elegans locomotion is a simple behavior that has been widely used to dissect genetic components of behavior, synaptic transmission, and muscle function. Many of the paradigms that have been created to study C. elegans locomotion rely on qualitative experimenter observation. Here we report the implementation of an automated tracking system developed to quantify the locomotion of multiple individual worms in parallel.
Methodology/Principal Findings
Our tracking system generates a consistent measurement of locomotion that allows direct comparison of results across experiments and experimenters and provides a standard method to share data between laboratories. The tracker utilizes a video camera attached to a zoom lens and a software package implemented in MATLABĀ®. We demonstrate several proof-of-principle applications for the tracker including measuring speed in the absence and presence of food and in the presence of serotonin. We further use the tracker to automatically quantify the time course of paralysis of worms exposed to aldicarb and levamisole and show that tracker performance compares favorably to data generated using a hand-scored metric.
Conclusions/Signficance
Although this is not the first automated tracking system developed to measure C. elegans locomotion, our tracking software package is freely available and provides a simple interface that includes tools for rapid data collection and analysis. By contrast with other tools, it is not dependent on a specific set of hardware. We propose that the tracker may be used for a broad range of additional worm locomotion applications including genetic and chemical screening
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Development of a Clinical MALDI-ToF Mass Spectrometry Assay for SARS-CoV-2: Rational Design and Multi-Disciplinary Team Work.
The COVID-19 pandemic caused by the SARS-CoV-2 coronavirus has stretched national testing capacities to breaking points in almost all countries of the world. The need to rapidly screen vast numbers of a country's population in order to control the spread of the infection is paramount. However, the logistical requirement for reagent supply (and associated cost) of RT-PCR based testing (the current front-line test) have been hugely problematic. Mass spectrometry-based methods using swab and gargle samples have been reported with promise, but have not approached the task from a systematic analysis of the entire diagnostic process. Here, the pipeline from sample processing, the biological characteristics of the pathogen in human biofluid, the downstream bio- and physical-chemistry and the all-important data processing with clinical interpretation and reporting, are carefully compiled into a single high-throughput and reproducible rapid process. Utilizing MALDI-ToF mass spectrometric detection to viral envelope glycoproteins in a systems biology-multidisciplinary team approach, we have achieved a multifaceted clinical MALDI ToF MS screening test, primarily (but not limited to) SARS-CoV-2, with direct application to other future epidemics/pandemics that may arise. The clinical information generated not only includes SARS-CoV-2 coronavirus detection-(Spike protein fragments S1, S2b, S2a peaks), but other respiratory viral infections detected as well as an assessment of generalised oral upper respiratory immune response (elevated total Ig light chain peak) and a measure of the viral immune response (elevated intensity of IgA heavy chain peak). The advantages of the method include; (1) ease of sampling, (2) speed of analysis, and much reduced cost of testing. These features reveal the diagnostic utility of MALDI-ToF mass spectrometry as a powerful and economically attractive global solution
Method and system for aligning fibers during electrospinning
A method and system are provided for aligning fibers in an electrospinning process. A jet of a fiberizable material is directed towards an uncharged collector from a dispensing location that is spaced apart from the collector. While the fiberizable material is directed towards the collector, an elliptical electric field is generated via the electrically charged dispenser and an oppositely-charged control location. The field spans between the dispensing location and the control location that is within line-of-sight of the dispensing location, and impinges upon at least a portion of the collector. Various combinations of numbers and geometries of dispensers, collectors, and electrodes can be used
Identification of potential āRemediesā for Air Pollution (nitrogen) Impacts on Designated Sites (RAPIDS)
Atmospheric nitrogen (N) deposition is a significant threat to semi-natural habitats and species in the UK, resulting in on-going erosion of habitat quality and declines in many species of high conservation value. The project focused on impacts and remedies for designated conservation sites, especially Natura 2000 sites protected under the EU Habitats Directive. However, the approach and certainly the measures could be equally applied to other areas of high conservation value. Evidence was drawn together to develop a framework for identifying key N threats at individual sites as a basis to target mitigation options in the context of potential legislative, voluntary and financial instruments
Site nitrogen action plans (SNAPs) for native woodland sites in Wales
Report to Snowdonia National Park Authority. Air pollution by ammonia and other nitrogen (N) compounds causes damage to habitats and wildlife, especially to sensitive lower plant communities such as lichens and mosses. The SNAPs project investigated the sources of N pollution at five woodland sites in Wales, and assessed how pollution levels and their effects on the woodland could be mitigated. The main source of ammonia at the sites studied was low-intensity beef and sheep farming. While some ammonia disperses over large distances, large amounts of ammonia from a given source are deposited within a few hundred metres, so nearby sources are important. Action is needed to limit regional and international flows of air pollution, but considerable improvements could be made by reducing the emissions from nearby sources of ammonia. The most useful measures are covering slurry stores; hard standing at feeding stations; and injecting slurry into the soil rather than broadcasting onto the ground surface. Some conservation sites are very large, and if particularly sensitive areas can be identified within sites, this could help identify off-site mitigation measures, which can be applied to sources nearest the sensitive area. For woodlands, on-site measures have only limited potential for reducing the ecological impacts of nitrogen pollution. Nitrogen generally increases plant growth and litter production, causing more shading of the ground surface. These effects can be reduced in woodlands by increasing scrub clearance, or grazing. However, these measures may have other effects on the site, and remove very little nitrogen from the system, meaning that it continues to accumulate in the vegetation and soil. Ultimately, nitrogen-sensitive features within woodland sites can only be safeguarded if nitrogen emissions decrease both locally and regionally
Coordination of opposing sex-specific and core muscle groups regulates male tail posture during Caenorhabditis elegans male mating behavior
Background
To survive and reproduce, animals must be able to modify their motor behavior in response to changes in the environment. We studied a complex behavior of Caenorhabditis elegans, male mating behavior, which provided a model for understanding motor behaviors at the genetic, molecular as well as circuit level. C. elegans male mating behavior consists of a series of six sub-steps: response to contact, backing, turning, vulva location, spicule insertion, and sperm transfer. The male tail contains most of the sensory structures required for mating, in addition to the copulatory structures, and thus to carry out the steps of mating behavior, the male must keep his tail in contact with the hermaphrodite. However, because the hermaphrodite does not play an active role in mating and continues moving, the male must modify his tail posture to maintain contact. We provide a better understanding of the molecular and neuro-muscular pathways that regulate male tail posture during mating.
Results
Genetic and laser ablation analysis, in conjunction with behavioral assays were used to determine neurotransmitters, receptors, neurons and muscles required for the regulation of male tail posture. We showed that proper male tail posture is maintained by the coordinated activity of opposing muscle groups that curl the tail ventrally and dorsally. Specifically, acetylcholine regulates both ventral and dorsal curling of the male tail, partially through anthelmintic levamisole-sensitive, nicotinic receptor subunits. Male-specific muscles are required for acetylcholine-driven ventral curling of the male tail but dorsal curling requires the dorsal body wall muscles shared by males and hermaphrodites. Gamma-aminobutyric acid activity is required for both dorsal and ventral acetylcholine-induced curling of the male tail and an inhibitory gamma-aminobutyric acid receptor, UNC-49, prevents over-curling of the male tail during mating, suggesting that cross-inhibition of muscle groups helps maintain proper tail posture.
Conclusion
Our results demonstrated that coordination of opposing sex-specific and core muscle groups, through the activity of multiple neurotransmitters, is required for regulation of male tail posture during mating. We have provided a simple model for regulation of male tail posture that provides a foundation for studies of how genes, molecular pathways, and neural circuits contribute to sensory regulation of this motor behavior
What is the most ecologically-meaningful metric of nitrogen deposition?
Nitrogen (N) deposition poses a severe risk to global terrestrial ecosystems, and managing this threat is an important focus for air pollution science and policy. To understand and manage the impacts of N deposition, we need metrics which accurately reflect N deposition pressure on the environment, and are responsive to changes in both N deposition and its impacts over time. In the UK, the metric typically used is a measure of total N deposition over 1ā3 years, despite evidence that N accumulates in many ecosystems and impacts from low-level exposure can take considerable time to develop. Improvements in N deposition modelling now allow the development of metrics which incorporate the long-term history of pollution, as well as current exposure. Here we test the potential of alternative N deposition metrics to explain vegetation compositional variability in British semi-natural habitats. We assembled 36 individual datasets representing 48,332 occurrence records in 5479 quadrats from 1683 sites, and used redundancy analyses to test the explanatory power of 33 alternative N metrics based on national pollutant deposition models. We find convincing evidence for N deposition impacts across datasets and habitats, even when accounting for other large-scale drivers of vegetation change. Metrics that incorporate long-term N deposition trajectories consistently explain greater compositional variance than 1ā3āÆyearāÆN deposition. There is considerable variability in results across habitats and between similar metrics, but overall we propose that a thirty-year moving window of cumulative deposition is optimal to represent impacts on plant communities for application in science, policy and management
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