1,848 research outputs found
Notiser ur sällskapets pro Fauna & Flora Fennica förhandlingar
Bihang till Acta Societatis scientiarum Fennicae
A precise determination of chlorinity of sea water using the Ag-AgCl indicator electrode
A knowledge of the relative currents of the oceans depends to a large extent upon a knowledge of the distribution of mass. Measurements of temperature and cblorinity are made to furnish the necessary data for the computations of the density
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ranacapa: An R package and Shiny web app to explore environmental DNA data with exploratory statistics and interactive visualizations.
Environmental DNA (eDNA) metabarcoding is becoming a core tool in ecology and conservation biology, and is being used in a growing number of education, biodiversity monitoring, and public outreach programs in which professional research scientists engage community partners in primary research. Results from eDNA analyses can engage and educate natural resource managers, students, community scientists, and naturalists, but without significant training in bioinformatics, it can be difficult for this diverse audience to interact with eDNA results. Here we present the R package ranacapa, at the core of which is a Shiny web app that helps perform exploratory biodiversity analyses and visualizations of eDNA results. The app requires a taxonomy-by-sample matrix and a simple metadata file with descriptive information about each sample. The app enables users to explore the data with interactive figures and presents results from simple community ecology analyses. We demonstrate the value of ranacapa to two groups of community partners engaging with eDNA metabarcoding results
On the bioeconomics of marine reserves when dispersal evolves
Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of John Wiley & Sons for personal use, not for redistribution. The definitive version was published in Natural Resource Modeling 28 (2015): 456-474, doi:10.1111/nrm.12075.Marine reserves are an increasingly used and potentially contentious tool in fisheries management. Depending upon the way that individuals move, no-take marine reserves can be necessary for maximizing equilibrium rent in some simple mathematical models. The implementation of no-take marine reserves often generates a redistribution of fishing effort in space. This redistribution of effort, in turn, produces sharp spatial gradients in mortality rates for the targeted stock. Using a two-patch model, we show that the existence of such gradients is a sufficient condition for the evolution of an evolutionarily stable conditional dispersal strategy. Thus, the dispersal strategy of the fish depends upon the harvesting strategy of the manager and vice versa. We find that an evolutionarily stable optimal harvesting strategy (ESOHS)—one which maximizes equilibrium rent given that fish disperse in an evolutionarily stable manner– - never includes a no-take marine reserve. This strategy is economically unstable in the short run because a manager can generate more rent by disregarding the possibility of dispersal evolution. Simulations of a stochastic evolutionary process suggest that such a short-run, myopic strategy performs poorly compared to the ESOHS over the long run, however, as it generates rent that is lower on average and higher in variability.This material is based upon work supported by funding from: The
Woods Hole Oceanographic Institution's Investment in Science Fund to MGN; The Recruitment
Program of Global Experts to YL; The University of Tennessee Center for Business and Economics
Research to SL; and the U.S. National Science Foundation (NSF) through grants OCE-1031256,
DEB-1257545, and DEB-1145017 to MGN, CNH-0707961 to GEH, DMS-1411476 to YL; and NSF
Graduate Research Fellowships under Grant No. 1122374 to EAM and ES
Tactile thresholds are preserved yet complex sensory function is impaired over the lumbar spine of chronic non-specific low back pain patients. A preliminary investigation
Objectives: To investigate impairments in sensory function in chronic non-specific low back pain patients and the relationship between any impairment and the clinical features of the condition. Design: A cross-sectional case-control study. Setting: Laboratory based study. Participants: Nineteen chronic non-specific low back pain patients and nineteen healthy controls. Main Outcome measures: Tactile threshold, two point discrimination distance and accuracy at a task involving recognizing letters drawn over the skin of the lower back (graphaesthesia) were assessed over the lumbar spine in both groups. Pain duration, pain intensity, physical function, anxiety and depression were assessed by questionnaire in the back pain group Results: We found no difference in tactile threshold between the two groups (median difference 0.00 95% CI -0.04 – 0.04). There was a significant difference between controls and back pain patients for two point discrimination (mean difference 17.85 95% CI 5.93 – 29.77) and graphaesthesia accuracy (mean difference 6.13 95% CI 1.27-10.99). Low back pain patients had a larger lumbar two point discrimination distance threshold and a greater letter recognition error rate. In the patient group, we found no relationship between clinical profile and sensory function and no relationship between the sensory tests. Conclusions: These data support existing findings of perceptual abnormalities in chronic non-specific low back pain patients and are suggestive of cortical rather than peripheral sensory dysfunction. Amelioration of these abnormalities may present a target for therapeutic intervention
Development of the Variable Dexterity Test: construction, reliability and validity
Background/Aims: This article introduces a dexterity test designed to assess individual types of
dexterity used to carry out activities of daily living (ADL). The Variable Dexterity Test (VDT) was
developed as part of a wider study, the broader aim being to fully understand dexterity and its effect
on human-product interaction during ADL. This was done with a view to improve occupational therapy
methods when assessing dexterity and general hand function.
Methods: The control group consisted of 24 healthy participants. Estimates of reliability and validity
were evaluated in this pilot study. Inter-rater and test-retest reliability were assessed using a one-way
ANOVA. The validity of the test was estimated by correlating participants’ VDT scores with their
proficiency to complete four ADL task actions and a standardised dexterity test (Purdue Pegboard Test).
Results: The test produced consistent results among the control group with both a single assessor
(test‑retest reliability) and multiple assessors (inter‑rater reliability). High correlations between
participants’ VDT scores and proficiency to perform ADL were found for most of the subtests. There
was also a high correlation between participants’ scores from the Purdue Pegboard Test and the VDT.
Conclusions: The VDT proved to be a flexible, reliable and valid tool that assesses dexterity based on
ability to carry out ADL. Validity and reliability estimates show encouraging values, which recognises
that the VDT can be used as an accurate method to assess more than one type of dexterity.</p
Memory-delineated subtypes of schizophrenia: Relationship to clinical, neuroanatomical, and neurophysiological measures.
Memory performance was examined in patients with schizophrenia to determine whether subgroups conforming to cortical and subcortical dementias could be identified and, if so, whether subgroups differed on clinical, neuroanatomical, and neurophysiological measures. A cluster analysis of California Verbal Learning Test performance classified patients into 3 subgroups. Two groups exhibited memory deficits consistent with the cortical–subcortical distinction, whereas 1 group was unimpaired. Cortical patients tended to be male, and they had earlier illness onset, reduced temporal lobe gray matter, and hypometabolism. Subcortical patients had ventricular enlargement and more negative symptoms. Unimpaired patients had fewer negative symptoms and dorsal medial prefrontal hypermetabolism. The authors con-clude that categorizing patients on the basis of memory deficits may yield neurobiologically meaningful disease subtypes. There is increasing consensus that Kraepelin’s conceptu-alization of schizophrenia as a disorder characterized by disturbed cognition rather than psychotic symptomatology was fundamentally correct (see Sharma & Harvey, 2000, fo
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