587 research outputs found
Shape recognition: convexities, concavities and things in between.
Visual objects are effortlessly recognized from their outlines, largely irrespective of viewpoint. Previous studies have drawn different conclusions regarding the importance to shape recognition of specific shape features such as convexities and concavities. However, most studies employed familiar objects, or shapes without curves, and did not measure shape recognition across changes in scale and position. We present a novel set of random shapes with well-defined convexities, concavities and inflections (intermediate points), segmented to isolate each feature type. Observers matched the segmented reference shapes to one of two subsequently presented whole-contour shapes (target or distractor) that were re-scaled and re-positioned. For very short segment lengths, performance was significantly higher for convexities than for concavities or intermediate points and for convexities remained constant with increasing segment length. For concavities and intermediate points, performance improved with increasing segment length, reaching convexity performance only for long segments. No significant differences between concavities and intermediates were found. These results show for the first time that closed curvilinear shapes are encoded using the positions of convexities, rather than concavities or intermediate regions. A shape-template model with no free parameters gave an excellent account of the data
A Look at Technology Use Across the Country: State Implementation of AT Practices for Infants and Toddlers
EI professionals from across the country recently participated in the Tots-n-Tech’s (TnT) Assistive Technology (AT) Program Self-Assessment. Part C Coordinators designated agency and program directors, regional coordinators, or other relevant people in their states to respond to the on-line self assessment of AT practices. The self-assessment is designed to provide a picture of how well recommended AT practices are implemented within state communities. Information from all respondents is combined to provide state-wide and regional views of how programs are doing in making AT available for infants and toddlers with disabilities or delayed development
Does life satisfaction reduce risk of incident hypertension and stroke? Evidence from the Whitehall II cohort
Background:
Previous studies showed life satisfaction is related to reduced risk of coronary heart disease and diabetes, but its association with other cardiometabolic endpoints including hypertension and stroke remains unexplored. This study examined life satisfaction's prospective association with incident hypertension and stroke in middle-aged adults.
Methods:
At baseline (1985–1988), 6225 healthy British civil servants aged 35–55 from the Whitehall II cohort completed the validated Satisfaction with Life Scale and provided information regarding sociodemographics, a range of health-related factors, and psychological distress. Incident hypertension was ascertained according to clinic-derived measures of systolic or diastolic blood pressure of ≥140/90 mmHg, respectively, or self-reports of either physician-diagnosed hypertension or hypertensive medication use. Incident stroke and transient ischemic attack (TIA) were ascertained by self-reported physician diagnosis. Follow-up assessments occurred every 2–5 years through 2017. Cox proportional hazards regression models estimated hazard ratios (HR) and 95% confidence intervals (CI) of hypertension and stroke/TIA risk separately.
Results:
Over a 31-year follow-up, 2703 cases of hypertension and 370 cases of stroke/TIA occurred. Life satisfaction was not related to risk of developing hypertension but was associated with 12% decreased risk of stroke/TIA after controlling for sociodemographics, health status, and health behaviors (HRper 1-SD = 0.88; 95%CI = 0.79–0.98). However, the association was attenuated after adjustment for psychological distress.
Conclusions:
No robust associations were found between life satisfaction and incident hypertension and stroke/TIA, respectively, after accounting for well-established risk factors and psychological distress. More research is needed to understand why associations of life satisfaction with cardiometabolic health seem to vary across endpoints
Variations in the Peritrophic Matrix Composition of Heparan Sulphate from the Tsetse Fly, Glossina morsitans morsitans
Tsetse flies are the principal insect vectors of African trypanosomes—sleeping sickness in humans and Nagana in cattle. One of the tsetse fly species, Glossina morsitans morsitans, is host to the parasite, Trypanosoma brucei, a major cause of African trypanosomiasis. Precise details of the life cycle have yet to be established, but the parasite life cycle involves crossing the insect peritrophic matrix (PM). The PM consists of the polysaccharide chitin, several hundred proteins, and both glycosamino- and galactosaminoglycan (GAG) polysaccharides. Owing to the technical challenges of detecting small amounts of GAG polysaccharides, their conclusive identification and composition have not been possible until now. Following removal of PMs from the insects and the application of heparinases (bacterial lyase enzymes that are specific for heparan sulphate (HS) GAG polysaccharides), dot blots with a HS-specific antibody showed heparan sulphate proteoglycans (HSPGs) to be present, consistent with Glossina morsitans morsitans genome analysis, as well as the likely expression of the HSPGs syndecan and perlecan. Exhaustive HS digestion with heparinases, fluorescent labeling of the resulting disaccharides with BODIPY fluorophore, and separation by strong anion exchange chromatography then demonstrated the presence of HS for the first time and provided the disaccharide composition. There were no significant differences in the type of disaccharide species present between genders or between ages (24 vs. 48 h post emergence), although the HS from female flies was more heavily sulphated overall. Significant differences, which may relate to differences in infection between genders or ages, were evident, however, in overall levels of 2-O-sulphation between sexes and, for females, between 24 and 48 h post-emergence, implying a change in expression or activity for the 2-O-sulphotransferase enzyme. The presence of significant quantities of disaccharides containing the monosaccharide GlcNAc6S contrasts with previous findings in Drosophila melanogaster and suggests subtle differences in HS fine structure between species of the Diptera
The renaissance of Odum's outwelling hypothesis in 'Blue Carbon' science
The term ‘Blue Carbon’ was coined about a decade ago to highlight the important carbon sequestration capacity of coastal vegetated ecosystems. The term has paved the way for the development of programs and policies that preserve and restore these threatened coastal ecosystems for climate change mitigation. Blue carbon research has focused on quantifying carbon stocks and burial rates in sediments or accumulating as biomass. This focus on habitat-bound carbon led us to losing sight of the mobile blue carbon fraction. Oceans, the largest active reservoir of carbon, have become somewhat of a blind spot. Multiple recent investigations have revealed high outwelling (i.e., lateral fluxes or horizontal exports) of dissolved inorganic (DIC) and organic (DOC) carbon, as well as particulate organic carbon (POC) from blue carbon habitats. In this paper, we conceptualize outwelling in mangrove, saltmarsh, seagrass and macroalgae ecosystems, diagnose key challenges preventing robust quantification, and pave the way for future work integrating mobile carbon in the blue carbon framework. Outwelling in mangroves and saltmarshes is usually dominated by DIC (mostly as bicarbonate), while POC seems to be the major carbon species exported from seagrass meadows and macroalgae forests. Carbon outwelling science is still in its infancy, and estimates remain limited spatially and temporally. Nevertheless, the existing datasets imply that carbon outwelling followed by ocean storage is relevant and may exceed local sediment burial as a long-term (>centuries) blue carbon sequestration mechanism. If this proves correct as more data emerge, ignoring carbon outwelling may underestimate the perceived sequestration capacity of blue carbon ecosystems.publishedVersio
The renaissance of Odum\u27s outwelling hypothesis in \u27blue carbon\u27 science
The term ‘Blue Carbon’ was coined about a decade ago to highlight the important carbon sequestration capacity of coastal vegetated ecosystems. The term has paved the way for the development of programs and policies that preserve and restore these threatened coastal ecosystems for climate change mitigation. Blue carbon research has focused on quantifying carbon stocks and burial rates in sediments or accumulating as biomass. This focus on habitat-bound carbon led us to losing sight of the mobile blue carbon fraction. Oceans, the largest active reservoir of carbon, have become somewhat of a blind spot. Multiple recent investigations have revealed high outwelling (i.e., lateral fluxes or horizontal exports) of dissolved inorganic (DIC) and organic (DOC) carbon, as well as particulate organic carbon (POC) from blue carbon habitats. In this paper, we conceptualize outwelling in mangrove, saltmarsh, seagrass and macroalgae ecosystems, diagnose key challenges preventing robust quantification, and pave the way for future work integrating mobile carbon in the blue carbon framework. Outwelling in mangroves and saltmarshes is usually dominated by DIC (mostly as bicarbonate), while POC seems to be the major carbon species exported from seagrass meadows and macroalgae forests. Carbon outwelling science is still in its infancy, and estimates remain limited spatially and temporally. Nevertheless, the existing datasets imply that carbon outwelling followed by ocean storage is relevant and may exceed local sediment burial as a long-term ( \u3e centuries) blue carbon sequestration mechanism. If this proves correct as more data emerge, ignoring carbon outwelling may underestimate the perceived sequestration capacity of blue carbon ecosystems
Electronic sculpting of ligand-GPCR subtype selectivity:the case of angiotensin II
GPCR subtypes possess distinct functional
and pharmacological profiles,
and thus development of subtype-selective ligands has immense therapeutic
potential. This is especially the case for the angiotensin receptor
subtypes AT1R and AT2R, where a functional negative control has been
described and AT2R activation highlighted as an important cancer drug
target. We describe a strategy to fine-tune ligand selectivity for
the AT2R/AT1R subtypes through electronic control of ligand aromatic-prolyl
interactions. Through this strategy an AT2R high affinity (<i>K</i><sub>i</sub> = 3 nM) agonist analogue that exerted 18,000-fold
higher selectivity for AT2R versus AT1R was obtained. We show that
this compound is a negative regulator of AT1R signaling since it is
able to inhibit MCF-7 breast carcinoma cellular proliferation in the
low nanomolar range
Blueberry Research Progress Reports
The 1989 edition of the Blueberry Research Progress Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include:
1. Control of Secondary Blueberry Pests
2. Monitory Methods, Economic Injury Levels, and Action Thresholds of Secondary Blueberry Pests
3. Control of Blueberry Maggot
4. Phosphorus Dose/Response Curve
5. Nitrogen-Phosphorus Study
6. Multiple Cropping of Wild Stands
7. Changes in Sugars and Organic Acids of Blueberries During Development
8. Investigation of Preprocess Changes That Could Lead to the Development of a Simple and Inexpensive Method to Measure Preprocess Berry Spoilage
9. Development of Simple and Less Expensive Methods to Analyze Pesticides Used on Maine and Canadian Blueberries
10. Evaluation and Modification of Commercial Wipers
11. Effect of Rate and Formulation of Hexazinone on Bunchberry
12. Bracken Fern Control Alternatives
13. Evaluation of Hexazinone with Spot Treatments of Glyphosate Sethoxydim or Fluazifop-P for Bunchgrass Control
14. Directed Sprays of Glyphosate for Bunchberry Control
15. Evaluation of Norflurazon with or without Hexazinone for Bunchgrass Control
16. Selective Wiper and Mechanical Control of Dogbane
17. Evaluation of Sulfonyl Urea Herbicides for Bunchberry Control
18. Seedling Pruning Study
19. Evaluation of Sethoxydim in Lowbush Blueberry Fields
20. Blueberry Extension Program
21. Pollination of the Low-bush Blueberry by Native Bees
22. Postharvest Fungi of Lowbush Blueberries
23. Effects of Pruning Methods on Mummy Berry Incidenc
Asymmetric Image-Template Registration
Authors Manuscript received: 2010 May 4. 12th International Conference, London, UK, September 20-24, 2009, Proceedings, Part IA natural requirement in pairwise image registration is that the resulting deformation is independent of the order of the images. This constraint is typically achieved via a symmetric cost function and has been shown to reduce the effects of local optima. Consequently, symmetric registration has been successfully applied to pairwise image registration as well as the spatial alignment of individual images with a template. However, recent work has shown that the relationship between an image and a template is fundamentally asymmetric. In this paper, we develop a method that reconciles the practical advantages of symmetric registration with the asymmetric nature of image-template registration by adding a simple correction factor to the symmetric cost function. We instantiate our model within a log-domain diffeomorphic registration framework. Our experiments show exploiting the asymmetry in image-template registration improves alignment in the image coordinates.NAMIC (NIH NIBIB NAMIC U54-EB005149)NAC (NIH NCRR NAC P41- RR13218)mBIRN (NIH NCRR mBIRN U24-RR021382)NIH NINDS (R01-NS051826 Grant)National Science Foundation (U.S.) (CAREER Grant 0642971)NIBIB (R01 EB001550)NIBIB (R01EB006758)NCRR (R01 RR16594-01A1)NCRR (P41-RR14075)NINDS (R01 NS052585-01)Singapore. Agency for Science, Technology and Researc
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