277 research outputs found
Age-Related Changes in two Muscle Enzymes of the Hawk Moth
Aging has been associated with significant declines in muscle strength and mass. The specific molecular mechanisms behind these changes, however, are not well known. One potential mechanism behind muscle aging could be enzymatic dysfunction. This research examines the enzyme changes that occur in the dorsolateral flight muscles of the hawk moth. The hawk moth, Manduca sexta, is an excellent model of muscle aging due to its short lifespan, ease of rearing, and endothermic flight muscles. We assayed citrate synthase (CS) and ÎČ-hydroxyacyl-CoA dehydrogenase (HADH) to determine the activity of the tricarboxylic acid cycle and fatty acid oxidation, respectively. A significant change in HADH activity was observed in male hawk moths between daytime and nighttime, but this change was not detected in females. Significant changes in CS activity occurred between middle aged and aged female hawk moths. Overall, CS activity increased with age for females, and aged females showed less distinction between daytime and nighttime CS activity. Increases in CS activity suggest age-related TCA cycle dysfunction in female hawk moths. This research identifies how beta oxidation and TCA activity change differently for male and female hawk moths via aging
Knowledge will Propel Machine Understanding of Content: Extrapolating from Current Examples
Machine Learning has been a big success story during the AI resurgence. One
particular stand out success relates to learning from a massive amount of data.
In spite of early assertions of the unreasonable effectiveness of data, there
is increasing recognition for utilizing knowledge whenever it is available or
can be created purposefully. In this paper, we discuss the indispensable role
of knowledge for deeper understanding of content where (i) large amounts of
training data are unavailable, (ii) the objects to be recognized are complex,
(e.g., implicit entities and highly subjective content), and (iii) applications
need to use complementary or related data in multiple modalities/media. What
brings us to the cusp of rapid progress is our ability to (a) create relevant
and reliable knowledge and (b) carefully exploit knowledge to enhance ML/NLP
techniques. Using diverse examples, we seek to foretell unprecedented progress
in our ability for deeper understanding and exploitation of multimodal data and
continued incorporation of knowledge in learning techniques.Comment: Pre-print of the paper accepted at 2017 IEEE/WIC/ACM International
Conference on Web Intelligence (WI). arXiv admin note: substantial text
overlap with arXiv:1610.0770
Creating a Resilient Watering System to Benefit Kids with Exceptional Needs at Farm and Nature-Based School
Research shows exposure to nature is critical for child development. Turn Back Time, Inc., (TBT) provides farm and nature-based programs for children, including those with exceptional needs, to learn and develop through play in nature. The farmâs gardens provide the context, materials, tools, and opportunities needed to run TBTâs programs. A drought in 2016 dried up the farmâs water source, killing the gardens. The purpose of this project was to engineer a resilient watering system to reduce the gardensâ vulnerability to drought while ensuring TBTâs programs, and their associated benefits, can continue
Accumulation of muscle ankyrin repeat protein transcript reveals local activation of primary myotube endcompartments during muscle morphogenesis
The characteristic shapes and positions of each individual body muscle are established during the process of muscle morphogenesis in response to patterning information from the surrounding mesenchyme. Throughout muscle morphogenesis, primary myotubes are arranged in small parallel bundles, each myotube spanning the forming muscles from end to end. This unique arrangement potentially assigns a crucial role to primary myotube end regions for muscle morphogenesis. We have cloned muscle ankyrin repeat protein (MARP) as a gene induced in adult rat skeletal muscle by denervation. MARP is the rodent homologue of human C-193 (Chu, W., D.K. Burns, R.A. Swerick, and D.H. Presky. 1995. J. Biol. Chem. 270:10236-10245) and is identical to rat cardiac ankyrin repeat protein. (Zou, Y., S. Evans, J. Chen, H.-C. Kuo, R.P. Harvey, and K.R. Chien. 1997. Development. 124:793-804). In denervated muscle fibers, MARP transcript accumulated in a unique perisynaptic pattern. MARP was also expressed in large blood vessels and in cardiac muscle, where it was further induced by cardiac hypertrophy. During embryonic development, MARP was expressed in forming skeletal muscle. In situ hybridization analysis in mouse embryos revealed that MARP transcript exclusively accumulates at the end regions of primary myotubes during muscle morphogenesis. This closely coincided with the expression of thrombospondin-4 in adjacent prospective tendon mesenchyme, suggesting that these two compartments may constitute a functional unit involved in muscle morphogenesis. Transfection experiments established that MARP protein accumulates in the nucleus and that the levels of both MARP mRNA and protein are controlled by rapid degradation mechanisms characteristic of regulatory early response genes. The results establish the existence of novel regulatory muscle fiber subcompartments associated with muscle morphogenesis and denervation and suggest that MARP may be a crucial nuclear cofactor in local signaling pathways from prospective tendon mesenchyme to forming muscle and from activated muscle interstitial cells to denervated muscle fibers
Design and Integration of a High-Powered Model Rocket â III
The paper describes a project to design, assemble, and test propulsion, stage separation, and recovery systems for a high-powered model rocket. A first-principles model was used to evaluate the pressurization produced by the CO2 separation system. A prototype system was fabricated and tested. Circuit and coil design for the electromagnetic booster separation system was used to minimize the capacitance, reducing vehicle mass. Results of this analysis are presented. Two models were used to evaluate rocket motor performance, one to estimate the thrust and specific impulse, and the other the heat transfer rates in the motor. Descriptions of these models are presented. Finally, an autorotation recovery system was designed based on turbine, helicopter blade, and blade element momentum theories
Control of Nematodirus spp. infection by sheep flock owners in Northern Ireland
Publication history: Accepted - 10 October 2017; Published online - 19 October 2017.Background
To address a lack of information on the control of ovine helminth parasites in Northern Ireland (NI), a number of research projects have been undertaken, dealing with gastrointestinal nematodes, tapeworms and liver fluke. This investigation concerns Nematodirus and concentrates on three aspects of disease: farm management strategies for its control, derived from the results of a Questionnaire; the efficacy of treatment used by farmers, as determined by a coprological survey; and the hatching requirements of Nematodirus eggs, that is, whether prolonged chilling is a pre-requisite for hatching.
Results
A Questionnaire was sent to 252 sheep farmers in NI in March 2012 (covering the years 2009â2012) and replies were received from 228 farmers. Under-dosing, inaccurate calibration of equipment and inappropriate product choice were poor practices identified. Following this survey, the efficacy of treatment of Nematodirus spp. in sheep flocks was evaluated in April and May 2012. Sampling kits were sent to 51 flock owners, all of whom returned pre- and post-anthelmintic dosing faecal samples to the laboratory for analysis. At the time of treatment, 41 flocks were positive for Nematodirus (as diagnosed by the presence of eggs). Reduced benzimidazole efficacy was detected in 35.7% of flocks tested (n = 28). Although only involving a small number of flocks, reduced efficacy of levamisole treatment was detected in 50%, of avermectins in 33% and of moxidectin in 75% of flocks tested (n = 2, 6 and 4, respectively). In the egg hatch experiment, carried out under âchilledâ and ânon-chilledâ conditions, 43% of the eggs in the ânon-chilledâ group were able to hatch, compared to 100% in the âchilledâ group.
Conclusions
The identification of inefficient control strategies argues for continued education of stockholders, in order to improve their management programmes. This is particularly important where the practices might impact on the development of anthelmintic resistance, which has been shown to exist on NI farms. The appropriate choice of anthelmintic is a vital part of this plan. The ability of eggs to hatch under non-chilled conditions demonstrates a flexibility in hatching behaviour. This may represent an adaptation to climate change and account for the recent emergence of a second, autumnal peak of infection
Global dataset on seagrass meadow structure, biomass and production
Seagrass meadows provide valuable socio-ecological ecosystem services, including a key role in climate change mitigation and adaption. Understanding the natural history of seagrass meadows across environmental gradients is crucial to deciphering the role of seagrasses in the global ocean. In this data collation, spatial and temporal patterns in seagrass meadow structure, biomass and production data are presented as a function of biotic and abiotic habitat characteristics. The biological traits compiled include measures of meadow structure (e.g. percent cover and shoot density), biomass (e.g. above-ground biomass) and production (e.g. shoot production). Categorical factors include bioregion, geotype (coastal or estuarine), genera and year of sampling. This dataset contains data extracted from peer-reviewed publications published between 1975 and 2020 based on a Web of Science search and includes 11 data variables across 12 seagrass genera. The dataset excludes data from mesocosm and field experiments, contains 14271 data points extracted from 390 publications and is publicly available on the PANGAEAÂź data repository (10.1594/PANGAEA.929968; Strydom et al., 2021). The top five most studied genera are Zostera, Thalassia, Cymodocea, Halodule and Halophila (84 % of data), and the least studied genera are Phyllospadix, Amphibolis and Thalassodendron (2.3 % of data). The data hotspot bioregion is the Tropical Indo-Pacific (25 % of data) followed by the Tropical Atlantic (21 %), whereas data for the other four bioregions are evenly spread (ranging between 13 and 15 % of total data within each bioregion). From the data compiled, 57 % related to seagrass biomass and 33 % to seagrass structure, while the least number of data were related to seagrass production (11 % of data). This data collation can inform several research fields beyond seagrass ecology, such as the development of nature-based solutions for climate change mitigation, which include readership interested in blue carbon, engineering, fisheries, global change, conservation and policy
A study of the reactivity of cyclic aminomethylammonium mannich salts
A novel method for the preparation of aminoalkylaminomethyl products was developed utilising novel Mannich-type salts featuring a R 2NCH 2NR 3 + moiety. This methodology showed good nucleophile scope and was successfully employed in reactions under basic, acidic, and neutral conditions. A wide range of diamine products was successfully synthesised, including a neuropeptide Y antagonist
Maternal trait personality and breastfeeding duration: the importance of confidence and social support
AIM: To explore associations among breastfeeding duration, maternal personality and maternal attitudes and experiences of breastfeeding. BACKGROUND: Understanding influences on breastfeeding initiation and duration is critical to increasing breastfeeding rates and supporting new mothers. Maternal characteristics such as selfâefficacy, knowledge and confidence are known to enable women to breastfeed, but little is known about the influence of maternal trait personality on breastfeeding. DESIGN: An exploratory crossâsectional survey. METHOD: A total of 602 mothers with an infant aged 6â12Â months old completed a selfâreport questionnaire examining maternal trait personality, breastfeeding duration and attitudes and experiences of breastfeeding. Data were collected between MarchâJune 2009. RESULTS: Mothers who reported high levels of extraversion, emotional stability and conscientiousness were significantly more likely to initiate and continue breastfeeding for a longer duration. Attitudes and experiences significantly associated with these personality traits such as perceived difficulties and lack of support may explain these patterns. For example, characteristics associated with introversion and anxiety may prevent women from seeking support or challenging negative attitudes of others at this critical time. CONCLUSION: Understanding the influence of maternal personality may thus be a useful tool in antenatal support to recognize women who may need extra, directed support while facilitating discussion of potential barriers to breastfeeding
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