852 research outputs found
Environmental Circadian Disruption Elevates the IL-6 Response to Lipopolysaccharide in Blood
The immune system is regulated by circadian clocks within the brain and immune cells. Environmental circadian disruption (ECD), consisting of a 6-h phase advance of the light:dark cycle once a week for 4 weeks, elevates the inflammatory response to lipopolysaccharide (LPS) both in vivo and in vitro. This indicates that circadian disruption adversely affects immune function; however, it remains unclear how the circadian system regulates this response under ECD conditions. Here, we develop an assay using ex vivo whole-blood LPS challenge to investigate the circadian regulation of immune responses in mice and to determine the effects of ECD on these rhythms. LPS-induced IL-6 release in whole blood was regulated in a circadian manner, peaking during subjective day under both entrained and free-running conditions. This LPS-induced IL-6 release rhythm was associated with daily variation in both white blood cell counts and immune cell responsiveness. ECD increased the overall level of LPS-induced IL-6 release by increasing immune cell responsiveness and not by affecting immune cell number or the circadian regulation of this rhythm. This indicates that ECD produces pathological immune responses by increasing the proinflammatory responses of immune cells. Also, this newly developed whole blood assay can provide a noninvasive longitudinal method to quantify potential health consequences of circadian disruption in humans
Mine boundary detection using partially ordered Markov models
Detection of objects in images in an automated fashion is necessary for many applications, including automated target recognition. In this paper, we present results of an automated boundary detection procedure using a new subclass of Markov random fields (MRFs), called partially ordered Markov models (POMMs). POMMs offer computational advantages over general MRFs. We show how a POMM can model the boundaries in an image. Our algorithm for boundary detection uses a Bayesian approach to build a posterior boundary model that locates edges of objects having a closed loop boundary. We apply our method to images of mines with very good results. 2004 Copyright SPIE - The International Society for Optical Engineering
The de Morton Mobility Index (DEMMI): An essential health index for an ageing world
BACKGROUND: Existing instruments for measuring mobility are inadequate for accurately assessing older people across the broad spectrum of abilities. Like other indices that monitor critical aspects of health such as blood pressure tests, a mobility test for all older acute medical patients provides essential health data. We have developed and validated an instrument that captures essential information about the mobility status of older acute medical patients. METHODS: Items suitable for a new mobility instrument were generated from existing scales, patient interviews and focus groups with experts. 51 items were pilot tested on older acute medical inpatients. An interval-level unidimensional mobility measure was constructed using Rasch analysis. The final item set required minimal equipment and was quick and simple to administer. The de Morton Mobility Index (DEMMI) was validated on an independent sample of older acute medical inpatients and its clinimetric properties confirmed. RESULTS: The DEMMI is a 15 item unidimensional measure of mobility. Reliability (MDC(90)), validity and the minimally clinically important difference (MCID) of the DEMMI were consistent across independent samples. The MDC(90) and MCID were 9 and 10 points respectively (on the 100 point Rasch converted interval DEMMI scale). CONCLUSION: The DEMMI provides clinicians and researchers with a valid interval-level method for accurately measuring and monitoring mobility levels of older acute medical patients. DEMMI validation studies are underway in other clinical settings and in the community. Given the ageing population and the importance of mobility for health and community participation, there has never been a greater need for this instrument
Cardiovascular complications of acute respiratory infections: current research and future directions.
Common Bacterial Infections and Risk of Dementia or Cognitive Decline: A Systematic Review.
BACKGROUND: Bacterial infections may be associated with dementia, but the temporality of any relationship remains unclear. OBJECTIVES: To summarize existing literature on the association between common bacterial infections and the risk of dementia and cognitive decline in longitudinal studies. METHODS: We performed a comprehensive search of 10 databases of published and grey literature from inception to 18 March 2019 using search terms for common bacterial infections, dementia, cognitive decline, and longitudinal study designs. Two reviewers independently performed the study selection, data extraction, risk of bias and overall quality assessment. Data were summarized through a narrative synthesis as high heterogeneity precluded a meta-analysis. RESULTS: We identified 3,488 studies. 9 met the eligibility criteria; 6 were conducted in the United States and 3 in Taiwan. 7 studies reported on dementia and 2 investigated cognitive decline. Multiple infections were assessed in two studies. All studies found sepsis (n = 6), pneumonia (n = 3), urinary tract infection (n = 1), and cellulitis (n = 1) increased dementia risk (HR 1.10; 95% CI 1.02-1.19) to (OR 2.60; 95% CI 1.84-3.66). The range of effect estimates was similar when limited to three studies with no domains at high risk of bias. However, the overall quality of evidence was rated very low. Studies on cognitive decline found no association with infection but had low power. CONCLUSION: Our review suggests common bacterial infections may be associated with an increased risk of subsequent dementia, after adjustment for multiple confounders, but further high-quality, large-scale longitudinal studies, across different healthcare settings, are recommended to further explore this association
The Mycobacterium tuberculosis MmpL11 cell wall lipid transporter is important for biofilm formation, intracellular growth, and nonreplicating persistence
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The New England boarding school : an analysis of its historical development and contemporary uncertainty of purpose.
This file contains a tiff sequence for PER2::LUC imagign data from SCN slices collected from Mouse#337 (rostral SCN = Slice1, middle SCN = Slice2, caudal SCN = Slice3)
Increasing forest loss worldwide from invasive pests requires new trade regulations
Loss of forests due to non-native invasive pests (including insects, nematodes, and pathogens) is a global phenomenon with profound population, community, ecosystem, and economic impacts. We review the magnitude of pest-associated forest loss worldwide and discuss the major ecological and evolutionary causes and consequences of these invasions. After compiling and analyzing a dataset of pest invasions from 21 countries, we show that the number of forest pest invasions recorded for a given country has a significant positive relationship with trade (as indicated by gross domestic product) and is not associated with the amount of forested land within that country. We recommend revisions to existing international protocols for preventing pest entry and proliferation, including prohibiting shipments of non-essential plants and plant products unless quarantined. Because invasions often originate from taxa that are scientifically described only after their introduction, current phytosanitary regulations – which target specific, already named organisms – are ineffective
Untethered soft robotic matter with passive control of shape morphing and propulsion
There is growing interest in creating untethered soft robotic matter that can repeatedly shape-morph and self-propel in response to external stimuli. Toward this goal, we printed soft robotic matter composed of liquid crystal elastomer (LCE) bilayers with orthogonal director alignment and different nematic-to-isotropic transition temperatures (T_(NI)) to form active hinges that interconnect polymeric tiles. When heated above their respective actuation temperatures, the printed LCE hinges exhibit a large, reversible bending response. Their actuation response is programmed by varying their chemistry and printed architecture. Through an integrated design and additive manufacturing approach, we created passively controlled, untethered soft robotic matter that adopts task-specific configurations on demand, including a self-twisting origami polyhedron that exhibits three stable configurations and a “rollbot” that assembles into a pentagonal prism and self-rolls in programmed responses to thermal stimuli
Untethered soft robotic matter with passive control of shape morphing and propulsion
There is growing interest in creating untethered soft robotic matter that can repeatedly shape-morph and self-propel in response to external stimuli. Toward this goal, we printed soft robotic matter composed of liquid crystal elastomer (LCE) bilayers with orthogonal director alignment and different nematic-to-isotropic transition temperatures (T_(NI)) to form active hinges that interconnect polymeric tiles. When heated above their respective actuation temperatures, the printed LCE hinges exhibit a large, reversible bending response. Their actuation response is programmed by varying their chemistry and printed architecture. Through an integrated design and additive manufacturing approach, we created passively controlled, untethered soft robotic matter that adopts task-specific configurations on demand, including a self-twisting origami polyhedron that exhibits three stable configurations and a “rollbot” that assembles into a pentagonal prism and self-rolls in programmed responses to thermal stimuli
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