1,745 research outputs found
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Integrating the inputs that shape pancreatic islet hormone release.
The pancreatic islet is a complex mini organ composed of a variety of endocrine cells and their support cells, which together tightly control blood glucose homeostasis. Changes in glucose concentration are commonly regarded as the chief signal controlling insulin-secreting beta cells, glucagon-secreting alpha cells and somatostatin-secreting delta cells. However, each of these cell types is highly responsive to a multitude of endocrine, paracrine, nutritional and neural inputs, which collectively shape the final endocrine output of the islet. Here, we review the principal inputs for each islet-cell type and the physiological circumstances in which these signals arise, through the prism of the insights generated by the transcriptomes of each of the major endocrine-cell types. A comprehensive integration of the factors that influence blood glucose homeostasis is essential to successfully improve therapeutic strategies for better diabetes management
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How do healthcare professionals working in accountable care organisations understand patient activation and engagement? Qualitative interviews across two time points.
ObjectiveIf patient engagement is the new 'blockbuster drug' why are we not seeing spectacular effects? Studies have shown that activated patients have improved health outcomes, and patient engagement has become an integral component of value-based payment and delivery models, including accountable care organisations (ACO). Yet the extent to which clinicians and managers at ACOs understand and reliably execute patient engagement in clinical encounters remains unknown. We assessed the use and understanding of patient engagement approaches among frontline clinicians and managers at ACO-affiliated practices.DesignQualitative study; 103 in-depth, semi-structured interviews.ParticipantsSixty clinicians and eight managers were interviewed at two established ACOs.ApproachWe interviewed healthcare professionals about their awareness, attitudes, understanding and experiences of implementing three key approaches to patient engagement and activation: 1) goal-setting, 2) motivational interviewing and 3) shared decision making. Of the 60 clinicians, 33 were interviewed twice leading to 93 clinician interviews. Of the 8 managers, 2 were interviewed twice leading to 10 manager interviews. We used a thematic analysis approach to the data.Key resultsInterviewees recognised the term 'patient activation and engagement' and had favourable attitudes about the utility of the associated skills. However, in-depth probing revealed that although interviewees reported that they used these patient activation and engagement approaches, they have limited understanding of these approaches.ConclusionsWithout understanding the concept of patient activation and the associated approaches of shared decision making and motivational interviewing, effective implementation in routine care seems like a distant goal. Clinical teams in the ACO model would benefit from specificity defining key terms pertaining to the principles of patient activation and engagement. Measuring the degree of understanding with reward that are better-aligned for behaviour change will minimise the notion that these techniques are already being used and help fulfil the potential of patient-centred care
Comparing Segmentation by Time and by Motion in Visual Search: An fMRI Investigation
Abstract
Brain activity was recorded while participants engaged in a difficult visual search task for a target defined by the spatial configuration of its component elements. The search displays were segmented by time (a preview then a search display), by motion, or were unsegmented. A preparatory network showed activity to the preview display, in the time but not in the motion segmentation condition. A region of the precuneus showed (i) higher activation when displays were segmented by time or by motion, and (ii) correlated activity with larger segmentation benefits behaviorally, regardless of the cue. Additionally, the results revealed that success in temporal segmentation was correlated with reduced activation in early visual areas, including V1. The results depict partially overlapping brain networks for segmentation in search by time and motion, with both cue-independent and cue-specific mechanisms.</jats:p
Socioâeconomic impact classification of alien taxa (SEICAT)
1 Many alien taxa are known to cause socioâeconomic impacts by affecting the different constituents of human wellâbeing (security; material and nonâmaterial assets; health; social, spiritual and cultural relations; freedom of choice and action). Attempts to quantify socioâeconomic impacts in monetary terms are unlikely to provide a useful basis for evaluating and comparing impacts of alien taxa because they are notoriously difficult to measure and important aspects of human wellâbeing are ignored.
2 Here, we propose a novel standardised method for classifying alien taxa in terms of the magnitude of their impacts on human wellâbeing, based on the capability approach from welfare economics. The core characteristic of this approach is that it uses changes in peoples' activities as a common metric for evaluating impacts on wellâbeing.
2 Impacts are assigned to one of five levels, from Minimal Concern to Massive, according to semiâquantitative scenarios that describe the severity of the impacts. Taxa are then classified according to the highest level of deleterious impact that they have been recorded to cause on any constituent of human wellâbeing. The scheme also includes categories for taxa that are not evaluated, have no alien population, or are data deficient, and a method for assigning uncertainty to all the classifications. To demonstrate the utility of the system, we classified impacts of amphibians globally. These showed a variety of impacts on human wellâbeing, with the cane toad (Rhinella marina) scoring Major impacts. For most species, however, no studies reporting impacts on human wellâbeing were found, i.e. these species were data deficient.
2 The classification provides a consistent procedure for translating the broad range of measures and types of impact into ranked levels of socioâeconomic impact, assigns alien taxa on the basis of the best available evidence of their documented deleterious impacts, and is applicable across taxa and at a range of spatial scales. The system was designed to align closely with the Environmental Impact Classification for Alien Taxa (EICAT) and the Red List, both of which have been adopted by the International Union of Nature Conservation (IUCN), and could therefore be readily integrated into international practices and policies
Cenozoic evolution of the eastern Black Sea: a test of depth-dependent stretching models
Subsidence analysis of the eastern Black Sea basin suggests that the stratigraphy of this deep, extensional basin can be explained by a predominantly pure-shear stretching history. A strain-rate inversion method that assumes pure-shear extension obtains good fits between observed and predicted stratigraphy. A relatively pure-shear strain distribution is also obtained when a strain-rate inversion algorithm is applied that allows extension to vary with depth without assuming its existence or form. The timing of opening of the eastern Black Sea, which occupied a back-arc position during the closure of the Tethys Ocean, has also been a subject of intense debate; competing theories called for basin opening during the Jurassic, Cretaceous or Paleocene/Eocene. Our work suggests that extension likely continued into the early Cenozoic, in agreement with stratigraphic relationships onshore and with estimates for the timing of arc magmatism. Further basin deepening also appears to have occurred in the last 20 myr. This anomalous subsidence event is focused in the northern part of the basin and reaches its peak at 15â10 Ma. We suggest that this comparatively localized shortening is associated with the northward movement of the Arabian plate. We also explore the effects of paleowater depth and elastic thickness on the results. These parameters are controversial, particularly for deep-water basins and margins, but their estimation is a necessary step in any analysis of the tectonic subsidence record stored in stratigraphy. <br/
Assistive Autonomous Ground Vehicles in Smart Grid
AbstractAutonomous Ground Vehicles (AGVs) are nominated for a wide range of applications in smart cities. This paper studies and simulates the potential field algorithm used for path planning of such AGVs to extend there application for automation and control of smart grids. Different sensors are studied and implemented in the algorithm to help the AGV navigate from an initial position to a goal by avoiding any obstacles in its path. A solution is analyzed and simulated for the problem of AGVs getting trapped in local minima. A new application for the AGVs as assistance in smart grid is also discussed. A real implementation of the project has also been done at the KTH Smart Mobility Lab, Sweden using the Nexus robots and the algorithm was implemented successfully
Root hairs aid soil penetration by anchoring the root surface to pore walls
The physical role of root hairs in anchoring the root tip during soil penetration was examined. Experiments using a hairless maize mutant (Zea mays: rth3â3) and its wild-type counterpart measured the anchorage force between the primary root of maize and the soil to determine whether root hairs enabled seedling roots in artificial biopores to penetrate sandy loam soil (dry bulk density 1.0â1.5g cm(â3)). Time-lapse imaging was used to analyse root and seedling displacements in soil adjacent to a transparent Perspex interface. Peak anchorage forces were up to five times greater (2.5N cf. 0.5N) for wild-type roots than for hairless mutants in 1.2g cm(â3) soil. Root hair anchorage enabled better soil penetration for 1.0 or 1.2g cm(â3) soil, but there was no significant advantage of root hairs in the densest soil (1.5g cm(â3)). The anchorage force was insufficient to allow root penetration of the denser soil, probably because of less root hair penetration into pore walls and, consequently, poorer adhesion between the root hairs and the pore walls. Hairless seedlings took 33h to anchor themselves compared with 16h for wild-type roots in 1.2g cm(â3) soil. Caryopses were often pushed several millimetres out of the soil before the roots became anchored and hairless roots often never became anchored securely.The physical role of root hairs in anchoring the root tip may be important in loose seed beds above more compact soil layers and may also assist root tips to emerge from biopores and penetrate the bulk soil
A New Approach toward Transition State Spectroscopy
Chirped-Pulse millimetre-Wave (CPmmW) rotational spectroscopy provides a new
class of information about photolysis transition state(s). Measured intensities
in rotational spectra determine species-isomer-vibrational populations,
provided that rotational populations can be thermalized. The formation and
detection of S0 vinylidene is discussed in the limits of low and high initial
rotational excitation. CPmmW spectra of 193 nm photolysis of Vinyl Cyanide
(Acrylonitrile) contain J=0-1 transitions in more than 20 vibrational levels of
HCN, HNC, but no transitions in vinylidene or highly excited local-bender
vibrational levels of acetylene. Reasons for the non-observation of the
vinylidene co-product of HCN are discussed.Comment: Accepted by Faraday Discussion
Physiological Indicators of Task Demand, Fatigue, and Cognition in Future Digital Manufacturing Environments
As Digital Manufacturing transforms traditionally physical work into more system-monitoring tasks, new methods are required for understanding people's mental workload and prolonged capacity for focused attention. Many physiological measures have shown promise for detecting changes in cognitive state, and recent advances in sensor technology offer minimally-invasive ways to monitor our cognitive activity. Previous research in functional near-infrared spectroscopy, for example, has observed changes in cerebral hemodynamic response during periods of high demand within tasks. This work investigated the relationships among task demand, fatigue, and attention degradation in a sustained attention task, and their effect on heart rate, breathing rate, nose temperature and hemodynamic response in the prefrontal cortex and middle temporal gyrus. Analysis revealed a small but significant effect of fatigue on heart rate relative to baseline, breathing rate and hemodynamic response. Task demand had a small but significant effect on breathing rate and nose temperature, both relative to baseline, but no difference between levels of demand was observed in heart rate or hemodynamic response. Our results provide insight into what physiological data can tell us about cognitive state, ability to focus, and the impact of fatigue over time
Mechanisms underlying selecting objects for action
We assessed the factors which affect the selection of objects for action, focusing on the role of action knowledge and its modulation by distracters. 14 neuropsychological patients and 10 healthy aged-matched controls selected pairs of objects commonly used together among distracters in two contexts: with real objects and with pictures of the same objects presented sequentially on a computer screen. Across both tasks, semantically related distracters led to slower responses and more errors than unrelated distracters and the object actively used for action was selected prior to the object that would be passively held during the action. We identified a sub-group of patients (N=6) whose accuracy was 2SD below the controls performances in the real object task. Interestingly, these impaired patients were more affected by the presence of unrelated distracters during both tasks than intact patients and healthy controls. Note the impaired had lesions to left parietal, right anterior temporal and bilateral pre-motor regions. We conclude that: (1) motor procedures guide object selection for action, (2) semantic knowledge affects action-based selection, (3) impaired action decision is associated with the inability to ignore distracting information and (4) lesions to either the dorsal or ventral visual stream can lead to deficits in making action decisions. Overall, the data indicate that impairments in everyday tasks can be evaluated using a simulated computer task. The implications for rehabilitation are discussed
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