46 research outputs found
EMG Analysis of Latissimus Dorsi, Erector Spinae and Middle Trapezius Muscle Activity during Spinal Rotation: A Pilot Study
Purpose/Hypothesis: Rotation of the spine, a complex movement that has yet to be fully understood, occurs regularly in activities of daily living (ADLs) and sport performance. Rotation (twisting) of the spine is a contributing factor in low back pain pathology and, by reports, has been associated with up to 60% of all back injuries. One of the largest muscles of the back, the latissimus dorsi (LD), is the only muscle to attach to the spine, pelvis, ribs, scapula, and humerus, and has the potential to impact the spine during many different activities. To date, there is limited research on the activity of the LD during spinal rotation or the effects of the muscle in rehabilitation programs for patients with low back pain (LBP). The purpose of this pilot study was to determine the LD muscle activity throughout spinal rotation during open and closed kinetic chain activities. Three hypotheses were established.
Malerials/Methods: Muscle activity of the LD was recorded by surface electrodes while the subjects performed rotation to the left and right in standing and in quadruped positions. Spinal rotation motion was initiated in the four test positions (standing rotation right/left, quadruped rotation right/left) by movement of the pelvis. Muscle activity was normalized to the maximal voluntary contraction (MVC) of the muscle. Significance was set at α=.05 level.
Results: The ipsilateral LD muscle produced significantly more muscle activity during spinal rotation while in fixed (quadruped) than the contralateral LD muscle (p
Discussion/Conclusion: The results of this study found the LD to be more active during the fixed positional movements. In the right fixed position, the left LD had significantly higher EMG activity than the MT and ES. However, this was not found to be true in the left fixed position. The data showed a significant difference between the activation of the right and left LD, which could be examined further in the future. Although the LD are active without the arms fixed, they demonstrate a significantly greater muscle activity when placed in a quadruped position. When in standing without the upper extremities fixed, other muscles have a greater function in rotation of the spine.
Clinical Relevance: This pilot study highlights the contributions of the LD muscle with spinal rotation and is the beginning of ongoing research efforts to address LD as part of the rotational movement strategy in individuals both with and without LBP. Many everyday movements require spinal rotation with the UEs fixed. Frequently, rehabilitation for LBP includes positions such as the quadruped position. LD is a muscle that should be considered when looking at spinal rotational movement systems
Exploring User Interface Improvements for Software Developers who are Blind
Software developers who are blind and interact with the computer non-visually face unique challenges with information retrieval. We explore the use of speech and Braille combined with software to provide an improved interface to aid with challenges associated with information retrieval. We motivate our design on common tasks performed by students in a software development course using a Microprocessor without Interlocked Pipeline Stages (MIPS) architecture simulation tool. We test our interface via a single-subject longitudinal study, and we measure and show improvement in both the user’s performance and the user experience
Novel plant-based meat alternatives: future opportunities and health considerations.
Current food systems threaten population and environmental health. Evidence suggests reduced meat and increased plant-based food consumption would align with climate change and health promotion priorities. Accelerating this transition requires greater understanding of determinants of plant-based food choice. A thriving plant-based food industry has emerged to meet consumer demand and support dietary shift towards plant-based eating. ‗Traditional' plant-based diets are low energy density, nutrient dense, low in saturated fat and purportedly associated with health benefits. However, fast-paced contemporary lifestyles continue to fuel growing demand for meat-mimicking plant-based convenience foods which are typically ultra-processed. Processing can improve product safety and palatability and enable fortification and enrichment. However, deleterious health consequences have been associated with ultra-processing, though there is a paucity of equivocal evidence regarding the health value of novel plant-based meat alternatives and their capacity to replicate the nutritional profile of meat-equivalents. Thus, despite the health halo often associated with plant-based eating, there is a strong rationale to improve consumer literacy of plant-based meat alternatives. Understanding the impact of extensive processing on health effects may help to justify the use of innovative methods designed to maintain health benefits associated with particular foods and ingredients. Furthering knowledge regarding the nutritional value of novel plant-based meat alternatives will increase consumer awareness thus support informed choice. Finally, knowledge of factors influencing engagement of target consumer subgroups with such products may facilitate production of desirable healthier plant-based meat alternatives. Such evidence-based food manufacturing practice has the potential to positively influence future individual and planetary health
Metabolic state alters economic decision making under risk in humans
Background: Animals' attitudes to risk are profoundly influenced by metabolic state (hunger and baseline energy stores). Specifically, animals often express a preference for risky (more variable) food sources when below a metabolic reference point (hungry), and safe (less variable) food sources when sated. Circulating hormones report the status of energy reserves and acute nutrient intake to widespread targets in the central nervous system that regulate feeding behaviour, including brain regions strongly implicated in risk and reward based decision-making in humans. Despite this, physiological influences per se have not been considered previously to influence economic decisions in humans. We hypothesised that baseline metabolic reserves and alterations in metabolic state would systematically modulate decision-making and financial risk-taking in humans.
Methodology/Principal Findings: We used a controlled feeding manipulation and assayed decision-making preferences across different metabolic states following a meal. To elicit risk-preference, we presented a sequence of 200 paired lotteries, subjects' task being to select their preferred option from each pair. We also measured prandial suppression of circulating acyl-ghrelin (a centrally-acting orexigenic hormone signalling acute nutrient intake), and circulating leptin levels (providing an assay of energy reserves). We show both immediate and delayed effects on risky decision-making following a meal, and that these changes correlate with an individual's baseline leptin and changes in acyl-ghrelin levels respectively.
Conclusions/Significance:
We show that human risk preferences are exquisitely sensitive to current metabolic state, in a direction consistent with ecological models of feeding behaviour but not predicted by normative economic theory. These substantive effects of state changes on economic decisions perhaps reflect shared evolutionarily conserved neurobiological mechanisms. We suggest that this sensitivity in human risk-preference to current metabolic state has significant implications for both real-world economic transactions and for aberrant decision-making in eating disorders and obesity
2017 Scientific Consensus Statement: land use impacts on the Great Barrier Reef water quality and ecosystem condition. Chapter 4: management options and their effectiveness
This chapter seeks to answer the following questions:
1. What are the values of the Great Barrier Reef?
2. How effective are better agricultural practices in improving water quality?
3. How can we improve the uptake of better agricultural practices?
4. What water quality improvement can non-agricultural land uses contribute?
5. How can Great Barrier Reef water quality improvement programs be improved?
Each section summarises the currently available peer reviewed literature and comments on implications for management and research gaps.
This chapter has a wider scope than previous Scientific Consensus Statements, including, for the first time, the social and governance dimensions of management and the management of non-agricultural land uses. These new sections are constrained by a lack of Great Barrier Reef–specific data and information. The relevance of information from other locations must be carefully considered. In comparison, the agricultural practice change and economics sections provide an update on material compiled as part of the 2013 Scientific Consensus Statement.
This report has been confined to peer reviewed literature, which is generally published in books and journals or major reports. There is additional evidence in grey literature, such as project and program reports, that has not been included here. Each section of this chapter has been compiled by a writing team and then revised following a series of review processes
Identifying Signatures of Natural Selection in Tibetan and Andean Populations Using Dense Genome Scan Data
High-altitude hypoxia (reduced inspired oxygen tension due to decreased barometric pressure) exerts severe physiological stress on the human body. Two high-altitude regions where humans have lived for millennia are the Andean Altiplano and the Tibetan Plateau. Populations living in these regions exhibit unique circulatory, respiratory, and hematological adaptations to life at high altitude. Although these responses have been well characterized physiologically, their underlying genetic basis remains unknown. We performed a genome scan to identify genes showing evidence of adaptation to hypoxia. We looked across each chromosome to identify genomic regions with previously unknown function with respect to altitude phenotypes. In addition, groups of genes functioning in oxygen metabolism and sensing were examined to test the hypothesis that particular pathways have been involved in genetic adaptation to altitude. Applying four population genetic statistics commonly used for detecting signatures of natural selection, we identified selection-nominated candidate genes and gene regions in these two populations (Andeans and Tibetans) separately. The Tibetan and Andean patterns of genetic adaptation are largely distinct from one another, with both populations showing evidence of positive natural selection in different genes or gene regions. Interestingly, one gene previously known to be important in cellular oxygen sensing, EGLN1 (also known as PHD2), shows evidence of positive selection in both Tibetans and Andeans. However, the pattern of variation for this gene differs between the two populations. Our results indicate that several key HIF-regulatory and targeted genes are responsible for adaptation to high altitude in Andeans and Tibetans, and several different chromosomal regions are implicated in the putative response to selection. These data suggest a genetic role in high-altitude adaption and provide a basis for future genotype/phenotype association studies necessary to confirm the role of selection-nominated candidate genes and gene regions in adaptation to altitude
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Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.
Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
The Trichoptera barcode initiative: a strategy for generating a species-level Tree of Life
DNA barcoding was intended as a means to provide species-level identifications through associating DNA sequences from unknown specimens to those from curated reference specimens. Although barcodes were not designed for phylogenetics, they can be beneficial to the completion of the Tree of Life. The barcode database for Trichoptera is relatively comprehensive, with data from every family, approximately two-thirds of the genera, and one-third of the described species. Most Trichoptera, as with most of life’s species, have never been subjected to any formal phylogenetic analysis. Here, we present a phylogeny with over 16 000 unique haplotypes as a working hypothesis that can be updated as our estimates improve. We suggest a strategy of implementing constrained tree searches, which allow larger datasets to
dictate the backbone phylogeny, while the barcode data fill out the tips of the tree. We also discuss how this phylogeny could be used to focus taxonomic attention on ambiguous species boundaries and hidden biodiversity. We suggest that systematists continue to differentiate
between ‘Barcode Index Numbers’ (BINs) and ‘species’ that have been formally described. Each has utility, but they are not synonyms. We highlight examples of integrative taxonomy, using both barcodes and morphology for species description. This article is part of the themed issue ‘From DNA barcodes to biomes’