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Discover the most talked about and latest scientific content & concepts.

Concept: Distinguish

242

Whether olfaction recognizes odorants by their shape, their molecular vibrations, or both remains an open and controversial question. A convenient way to address it is to test for odor character differences between deuterated and undeuterated odorant isotopomers, since these have identical ground-state conformations but different vibrational modes. In a previous paper (Franco et al. (2011) Proc Natl Acad Sci USA 108:9, 3797-802) we showed that fruit flies can recognize the presence of deuterium in odorants by a vibrational mechanism. Here we address the question of whether humans too can distinguish deuterated and undeuterated odorants. A previous report (Keller and Vosshall (2004) Nat Neurosci 7:4, 337-8) indicated that naive subjects are incapable of distinguishing acetophenone and d-8 acetophenone. Here we confirm and extend those results to trained subjects and gas-chromatography [GC]-pure odorants. However, we also show that subjects easily distinguish deuterated and undeuterated musk odorants purified to GC-pure standard. These results are consistent with a vibrational component in human olfaction.

Concepts: Spectroscopy, Olfaction, Perfume, Odor, Flavor, Aroma compound, Distinguish, Body odor

169

Distinguishing melanoma from dysplastic nevi can be challenging.

Concepts: Dysplastic nevus, Distinguish

31

Despite availability of advanced imaging, distinguishing radiation necrosis from recurrent brain tumors noninvasively is a big challenge in neuro-oncology. Our aim was to determine the feasibility of radiomic (computer-extracted texture) features in differentiating radiation necrosis from recurrent brain tumors on routine MR imaging (gadolinium T1WI, T2WI, FLAIR).

Concepts: Cancer, Brain, Oncology, Brain tumor, Magnetic resonance imaging, Distinguish

24

Sociometers are wearable sensors that continuously measure body movements, interactions, and speech. The purpose of this study is to test sociometers in a smart environment in a live clinical setting, to assess their reliability in capturing and quantifying data. The long-term goal of this work is to create an intelligent emergency department that captures real-time human interactions using sociometers to sense current system dynamics, predict future state, and continuously learn to enable the highest levels of emergency care delivery. Ten actors wore the devices during five simulated scenarios in the emergency care wards at a large non-profit medical institution. For each scenario, actors recited prewritten or structured dialogue while independent variables, e.g., distance, angle, obstructions, speech behavior, were independently controlled. Data streams from the sociometers were compared to gold standard video and audio data captured by two ward and hallway cameras. Sociometers distinguished body movement differences in mean angular velocity between individuals sitting, standing, walking intermittently, and walking continuously. Face-to-face (F2F) interactions were not detected when individuals were offset by 30°, 60°, and 180° angles. Under ideal F2F conditions, interactions were detected 50 % of the time (4/8 actor pairs). Proximity between individuals was detected for 13/15 actor pairs. Devices underestimated the mean duration of speech by 30-44 s, but were effective at distinguishing the dominant speaker. The results inform engineers to refine sociometers and provide health system researchers a tool for quantifying the dynamics and behaviors in complex and unpredictable healthcare environments such as emergency care.

Concepts: Psychology, Prediction, Urgent care, Angle, Emergency department, Montgomery Ward, Distinguish, Actor

23

To characterize the macular lesions in multifocal choroiditis using multimodal imaging (MMI) and to evaluate optical coherence tomography angiography (OCTA) in distinguishing neovascular from inflammatory lesions.

Concepts: Optics, Medical imaging, Ophthalmology, Tomography, Distinguish, Neovascularization

17

Distinguishing between the bones of sheep and goat is a notorious challenge in zooarchaeology. Several methodological contributions have been published at different times and by various people to facilitate this task, largely relying on a macro-morphological approach. This is now routinely adopted by zooarchaeologists but, although it certainly has its value, has also been shown to have limitations. Morphological discriminant criteria can vary in different populations and correct identification is highly dependent upon a researcher’s experience, availability of appropriate reference collections, and many other factors that are difficult to quantify. There is therefore a need to establish a more objective system, susceptible to scrutiny. In order to fulfil such a requirement, this paper offers a comprehensive morphometric method for the identification of sheep and goat postcranial bones, using a sample of more than 150 modern skeletons as a basis, and building on previous pioneering work. The proposed method is based on measurements-some newly created, others previously published-and its use is recommended in combination with the more traditional morphological approach. Measurement ratios, used to translate morphological traits into biometrical attributes, are demonstrated to have substantial diagnostic potential, with the vast majority of specimens correctly assigned to species. The efficacy of the new method is also tested with Discriminant Analysis, which provides a successful verification of the biometrical indices, a statistical means to select the most promising measurements, and an additional line of analysis to be used in conjunction with the others.

Concepts: Scientific method, Measurement, Value, Methodology, Distinguish, Correctness, Formal verification, Formal methods

9

Background: Physical activity is recommended to mitigate functional limitations associated with knee osteoarthritis (OA). However, it is unclear whether walking on its own protects against the development of functional limitation. Methods: Walking over 7 days was objectively measured as steps/day within a cohort of people with or at risk of knee OA from the Multicenter Osteoarthritis Study. Incident functional limitation over two years was defined by performance-based (gait speed ≤ 1.0 m/s) and self-report (WOMAC physical function ≥ 28/68) measures. We evaluated the association of steps/day at baseline with developing functional limitation two years later by calculating risk ratios adjusted for potential confounders. The number of steps/day that best distinguished risk for developing functional limitation was estimated from the maximum distance from chance on Receiver Operator Characteristic curves. Results: Among 1788 participants (mean age 67, mean BMI 31 kg/m(2) , female 60%), each additional 1000 steps/day was associated with a 16% and 18% reduction in incident functional limitation by performance-based and self-report measures, respectively. Walking < 6000 and < 5900 steps/day were the best thresholds to distinguish incident functional limitation by performance-based (67.3%/71.8% [sensitivity/specificity]) and self-report (58.7%/68.9%) measures, respectively. Conclusions: More walking was associated with less risk of functional limitation over two years. Walking ≥ 6000 steps/day provides a preliminary estimate of the level of walking activity to protect against developing functional limitation in people with or at risk of knee OA. © 2014 American College of Rheumatology.

Concepts: Statistics, Mathematics, Observational study, Osteoarthritis, Estimation, Gait, Distinguish, Limitations

6

Connected individuals (or nodes) in a network are more likely to be similar than two randomly selected nodes due to homophily and/or network influence. Distinguishing between these two influences is an important goal in network analysis, and generalized estimating equation (GEE) analyses of longitudinal dyadic network data are an attractive approach. It is not known to what extent such regressions can accurately extract underlying data generating processes. Therefore our primary objective is to determine to what extent, and under what conditions, does the GEE-approach recreate the actual dynamics in an agent-based model.

Concepts: Mathematical analysis, Model, Logic, Analysis, Social network, Distinguish, Social influence, Agent-based model

6

Juvenile idiopathic arthritis (JIA) is a heterogeneous group of conditions unified by the presence of chronic childhood arthritis without an identifiable cause. Systemic JIA (sJIA) is a rare form of JIA characterised by systemic inflammation. sJIA is distinguished from other forms of JIA by unique clinical features and treatment responses that are similar to autoinflammatory diseases. However, approximately half of children with sJIA develop destructive, long-standing arthritis that appears similar to other forms of JIA. Using genomic approaches, we sought to gain novel insights into the pathophysiology of sJIA and its relationship with other forms of JIA.

Concepts: Inflammation, Medicine, Rheumatoid arthritis, Rheumatology, Childhood, Arthritis, Juvenile idiopathic arthritis, Distinguish

5

While separate pieces of research found parents offer toddlers cues to express that they are (1) joking and (2) pretending, and that toddlers and preschoolers understand intentions to (1) joke and (2) pretend, it is not yet clear whether parents and toddlers consider joking and pretending to be distinct concepts. This is important as distinguishing these two forms of non-literal acts could open a gateway to understanding the complexities of the non-literal world, as well as the complexities of intentions in general. Two studies found parents offer explicit cues to help 16- to 24-month-olds distinguish pretending and joking. Across an action play study (n = 25) and a verbal play study (n = 40) parents showed more disbelief and less belief through their actions and language when joking versus pretending. Similarly, toddlers showed less belief through their actions, and older toddlers showed less belief through their language. Toddlers' disbelief could be accounted for by their response to parents' language and actions. Thus, these studies reveal a mechanism by which toddlers learn to distinguish joking and pretending. Parents offer explicit cues to distinguish these intentions, and toddlers use these cues to guide their own behaviors, which in turn allows toddlers to distinguish these intentional contexts.

Concepts: Understanding, Intention, Distinguish, Joke