1,532 research outputs found
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Place Attachment and Willingness to Pay: How Do Visitors Value State Parks?
Abstract
State parks provide benefits for members of the public who may not have access to natural environments. In this context, it is critical to understand how minority groups value and depend on state parks. To better understand these issues research was conducted during the summers of 2009 and 2010 at three state parks in north Georgia. Intercept surveys were administered to 929 state park visitors. Data pertaining to whether or not visitors perceived themselves as being dependent on state parks and were willing to pay for parks were collected. Results of an exploratory factor analysis suggested that place dependency varied by race/ethnicity, education and income. Results revealed a positive relationship between willingness to pay and place dependency. Results of this study may provide Georgia state park managers with a better understanding of how visitors, in particular minorities, value state parks
The "Artificial Mathematician" Objection: Exploring the (Im)possibility of Automating Mathematical Understanding
Reuben Hersh confided to us that, about forty years ago, the late Paul Cohen predicted to him that at some unspecified point in the future, mathematicians would be replaced by computers. Rather than focus on computers replacing mathematicians, however, our aim is to consider the (im)possibility of human mathematicians being joined by “artificial mathematicians” in the proving practice—not just as a method of inquiry but as a fellow inquirer
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Genetic variation in the HLA region is associated with susceptibility to herpes zoster.
Herpes zoster, commonly referred to as shingles, is caused by the varicella zoster virus (VZV). VZV initially manifests as chicken pox, most commonly in childhood, can remain asymptomatically latent in nerve tissues for many years and often re-emerges as shingles. Although reactivation may be related to immune suppression, aging and female sex, most inter-individual variability in re-emergence risk has not been explained to date. We performed a genome-wide association analyses in 22,981 participants (2280 shingles cases) from the electronic Medical Records and Genomics Network. Using Cox survival and logistic regression, we identified a genomic region in the combined and European ancestry groups that has an age of onset effect reaching genome-wide significance (P>1.0 × 10(-8)). This region tags the non-coding gene HCP5 (HLA Complex P5) in the major histocompatibility complex. This gene is an endogenous retrovirus and likely influences viral activity through regulatory functions. Variants in this genetic region are known to be associated with delay in development of AIDS in people infected by HIV. Our study provides further suggestion that this region may have a critical role in viral suppression and could potentially harbor a clinically actionable variant for the shingles vaccine
A viscoelastic deadly fluid in carnivorous pitcher plants
Background : The carnivorous plants of the genus Nepenthes, widely
distributed in the Asian tropics, rely mostly on nutrients derived from
arthropods trapped in their pitcher-shaped leaves and digested by their
enzymatic fluid. The genus exhibits a great diversity of prey and pitcher forms
and its mechanism of trapping has long intrigued scientists. The slippery inner
surfaces of the pitchers, which can be waxy or highly wettable, have so far
been considered as the key trapping devices. However, the occurrence of species
lacking such epidermal specializations but still effective at trapping insects
suggests the possible implication of other mechanisms. Methodology/Principal
Findings : Using a combination of insect bioassays, high-speed video and
rheological measurements, we show that the digestive fluid of Nepenthes
rafflesiana is highly viscoelastic and that this physical property is crucial
for the retention of insects in its traps. Trapping efficiency is shown to
remain strong even when the fluid is highly diluted by water, as long as the
elastic relaxation time of the fluid is higher than the typical time scale of
insect movements. Conclusions/Significance : This finding challenges the common
classification of Nepenthes pitchers as simple passive traps and is of great
adaptive significance for these tropical plants, which are often submitted to
high rainfalls and variations in fluid concentration. The viscoelastic trap
constitutes a cryptic but potentially widespread adaptation of Nepenthes
species and could be a homologous trait shared through common ancestry with the
sundew (Drosera) flypaper plants. Such large production of a highly
viscoelastic biopolymer fluid in permanent pools is nevertheless unique in the
plant kingdom and suggests novel applications for pest control
Correlation functions quantify super-resolution images and estimate apparent clustering due to over-counting
We present an analytical method to quantify clustering in super-resolution
localization images of static surfaces in two dimensions. The method also
describes how over-counting of labeled molecules contributes to apparent
self-clustering and how the effective lateral resolution of an image can be
determined. This treatment applies to clustering of proteins and lipids in
membranes, where there is significant interest in using super-resolution
localization techniques to probe membrane heterogeneity. When images are
quantified using pair correlation functions, the magnitude of apparent
clustering due to over-counting will vary inversely with the surface density of
labeled molecules and does not depend on the number of times an average
molecule is counted. Over-counting does not yield apparent co-clustering in
double label experiments when pair cross-correlation functions are measured. We
apply our analytical method to quantify the distribution of the IgE receptor
(Fc{\epsilon}RI) on the plasma membranes of chemically fixed RBL-2H3 mast cells
from images acquired using stochastic optical reconstruction microscopy (STORM)
and scanning electron microscopy (SEM). We find that apparent clustering of
labeled IgE bound to Fc{\epsilon}RI detected with both methods arises from
over-counting of individual complexes. Thus our results indicate that these
receptors are randomly distributed within the resolution and sensitivity limits
of these experiments.Comment: 22 pages, 5 figure
Advanced optical imaging in living embryos
Developmental biology investigations have evolved from static studies of embryo anatomy and into dynamic studies of the genetic and cellular mechanisms responsible for shaping the embryo anatomy. With the advancement of fluorescent protein fusions, the ability to visualize and comprehend how thousands to millions of cells interact with one another to form tissues and organs in three dimensions (xyz) over time (t) is just beginning to be realized and exploited. In this review, we explore recent advances utilizing confocal and multi-photon time-lapse microscopy to capture gene expression, cell behavior, and embryo development. From choosing the appropriate fluorophore, to labeling strategy, to experimental set-up, and data pipeline handling, this review covers the various aspects related to acquiring and analyzing multi-dimensional data sets. These innovative techniques in multi-dimensional imaging and analysis can be applied across a number of fields in time and space including protein dynamics to cell biology to morphogenesis
Reviewing the review:a qualitative assessment of the peer review process in surgical journals
Abstract Background Despite rapid growth of the scientific literature, no consensus guidelines have emerged to define the optimal criteria for editors to grade submitted manuscripts. The purpose of this project was to assess the peer reviewer metrics currently used in the surgical literature to evaluate original manuscript submissions. Methods Manuscript grading forms for 14 of the highest circulation general surgery-related journals were evaluated for content, including the type and number of quantitative and qualitative questions asked of peer reviewers. Reviewer grading forms for the seven surgical journals with the higher impact factors were compared to the seven surgical journals with lower impact factors using Fisher’s exact tests. Results Impact factors of the studied journals ranged from 1.73 to 8.57, with a median impact factor of 4.26 in the higher group and 2.81 in the lower group. The content of the grading forms was found to vary considerably. Relatively few journals asked reviewers to grade specific components of a manuscript. Higher impact factor journal manuscript grading forms more frequently addressed statistical analysis, ethical considerations, and conflict of interest. In contrast, lower impact factor journals more commonly requested reviewers to make qualitative assessments of novelty/originality, scientific validity, and scientific importance. Conclusion Substantial variation exists in the grading criteria used to evaluate original manuscripts submitted to the surgical literature for peer review, with differential emphasis placed on certain criteria correlated to journal impact factors
Star forming dwarf galaxies
Star forming dwarf galaxies (SFDGs) have a high gas content and low
metallicities, reminiscent of the basic entities in hierarchical galaxy
formation scenarios. In the young universe they probably also played a major
role in the cosmic reionization. Their abundant presence in the local volume
and their youthful character make them ideal objects for detailed studies of
the initial stellar mass function (IMF), fundamental star formation processes
and its feedback to the interstellar medium. Occasionally we witness SFDGs
involved in extreme starbursts, giving rise to strongly elevated production of
super star clusters and global superwinds, mechanisms yet to be explored in
more detail. SFDGs is the initial state of all dwarf galaxies and the relation
to the environment provides us with a key to how different types of dwarf
galaxies are emerging. In this review we will put the emphasis on the exotic
starburst phase, as it seems less important for present day galaxy evolution
but perhaps fundamental in the initial phase of galaxy formation.Comment: To appear in JENAM Symposium "Dwarf Galaxies: Keys to Galaxy
Formation and Evolution", P. Papaderos, G. Hensler, S. Recchi (eds.). Lisbon,
September 2010, Springer Verlag, in pres
How do you say ‘hello’? Personality impressions from brief novel voices
On hearing a novel voice, listeners readily form personality impressions of that speaker. Accurate or not, these impressions are known to affect subsequent interactions; yet the underlying psychological and acoustical bases remain poorly understood. Furthermore, hitherto studies have focussed on extended speech as opposed to analysing the instantaneous impressions we obtain from first experience. In this paper, through a mass online rating experiment, 320 participants rated 64 sub-second vocal utterances of the word ‘hello’ on one of 10 personality traits. We show that: (1) personality judgements of brief utterances from unfamiliar speakers are consistent across listeners; (2) a two-dimensional ‘social voice space’ with axes mapping Valence (Trust, Likeability) and Dominance, each driven by differing combinations of vocal acoustics, adequately summarises ratings in both male and female voices; and (3) a positive combination of Valence and Dominance results in increased perceived male vocal Attractiveness, whereas perceived female vocal Attractiveness is largely controlled by increasing Valence. Results are discussed in relation to the rapid evaluation of personality and, in turn, the intent of others, as being driven by survival mechanisms via approach or avoidance behaviours. These findings provide empirical bases for predicting personality impressions from acoustical analyses of short utterances and for generating desired personality impressions in artificial voices
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