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Visitors’ Climate Change Beliefs & Perceptions of Climate-Sensitive Resources at Great Sand Dunes National Park
Abstract
Ecological consequences associated with climate change are becoming increasingly noticeable in nature-based recreation areas. Research is therefore needed to better understand nature-based recreationists’ perceptions of, attitudes towards, and behavioral responses to climate change and resource impacts in parks. This study explored strategies for assessing and responding to visitor perceptions of climate change at Great Sand Dunes National Park (GRSA), Colorado. In the summer of 2011, researchers intercepted visitors at GRSD and invited them to complete an online questionnaire. Visitors reported strong beliefs that global climate change was currently happening, but less certainty regarding the belief that human activities are influencing climate. Studies such as this may provide information for interpreters and park staff regarding climate change, and increase visitors’ understanding of climate change. Future research could expand upon this exploratory study in an effort to inform resource management decisions and develop targeted climate change visitor education programs
Gallus GBrowse: a unified genomic database for the chicken
Gallus GBrowse (http://birdbase.net/cgi-bin/gbrowse/gallus/) provides online access to genomic and other information about the chicken, Gallus gallus. The information provided by this resource includes predicted genes and Gene Ontology (GO) terms, links to Gallus In Situ Hybridization Analysis (GEISHA), Unigene and Reactome, the genomic positions of chicken genetic markers, SNPs and microarray probes, and mappings from turkey, condor and zebra finch DNA and EST sequences to the chicken genome. We also provide a BLAT server (http://birdbase.net/cgi-bin/webBlat) for matching user-provided sequences to the chicken genome. These tools make the Gallus GBrowse server a valuable resource for researchers seeking genomic information regarding the chicken and other avian species
Dopamine Transporter Genetic Variants and Pesticides in Parkinson’s Disease
BackgroundResearch suggests that independent and joint effects of genetic variability in the dopamine transporter (DAT) locus and pesticides may influence Parkinson's disease (PD) risk.MaterialsMethodsIn 324 incident PD patients and 334 population controls from our rural California case-control study, we genotyped rs2652510, rs2550956 (for the DAT 5' clades), and the 3' variable number of tandem repeats (VNTR). Using geographic information system methods, we determined residential exposure to agricultural maneb and paraquat applications. We also collected occupational pesticide use data. Employing logistic regression, we calculated odds ratios (ORs) for clade diplotypes, VNTR genotype, and number of susceptibility (A clade and 9-repeat) alleles and assessed susceptibility allele-pesticide interactions.ResultsPD risk was increased separately in DAT A clade diplotype carriers [AA vs. BB: OR = 1.66; 95% confidence interval (CI), 1.08-2.57] and 3' VNTR 9/9 carriers (9/9 vs. 10/10: OR = 1.8; 95% CI, 0.96-3.57), and our data suggest a gene dosing effect. Importantly, high exposure to paraquat and maneb in carriers of one susceptibility allele increased PD risk 3-fold (OR = 2.99; 95% CI, 0.88-10.2), and in carriers of two or more alleles more than 4-fold (OR = 4.53; 95% CI, 1.70-12.1). We obtained similar results for occupational pesticide measures.DiscussionUsing two independent pesticide measures, we a) replicated previously reported gene-environment interactions between DAT genetic variants and occupational pesticide exposure in men and b) overcame previous limitations of nonspecific pesticide measures and potential recall bias by employing state records and computer models to estimate residential pesticide exposure.ConclusionOur results suggest that DAT genetic variability and pesticide exposure interact to increase PD risk
The ‘Facebook\u27 Effect: College Students\u27 Perceptions of Online Discussions in the Age of Social Networking
Despite the growing prominence of Facebook in the lives of college students, few studies have investigated the potential of these innovative web-based communication tools for engaging students in academic discussions. This study used a pre-test, post-test design in two introductory-level courses at a large public university to compare students’ (n = 107) perceptions of, attitudes toward, and perceived learning associated with two different online discussion tools: the Facebook group forum and a university-sponsored online tool. Although pre-course surveys indicated that few students enjoyed online discussions, postcourse analysis revealed significant changes in students’ opinions regarding the value and functionality of web-based discussion forums, with Facebook as their clear preference. Students who participated in Facebook discussions enjoyed the site’s familiarity, navigability, and aesthetically appealing interface. Facebook users also reported that they were able to become better acquainted with classmates, felt like valued participants in the course, and learned more course material. This study suggests that, if used appropriately, Facebook may help to increase college student engagement in certain learning contexts by cultivating classroom community and stimulating intellectual discourse
Binary-induced collapse of a compact, collisionless cluster
We improve and extend Shapiro's model of a relativistic, compact object which
is stable in isolation but is driven dynamically unstable by the tidal field of
a binary companion. Our compact object consists of a dense swarm of test
particles moving in randomly-oriented, initially circular, relativistic orbits
about a nonrotating black hole. The binary companion is a distant, slowly
inspiraling point mass. The tidal field of the companion is treated as a small
perturbation on the background Schwarzschild geometry near the hole; the
resulting metric is determined by solving the perturbation equations of Regge
and Wheeler and Zerilli in the quasi-static limit. The perturbed spacetime
supports Bekenstein's conjecture that the horizon area of a near-equilibrium
black hole is an adiabatic invariant. We follow the evolution of the system and
confirm that gravitational collapse can be induced in a compact collisionless
cluster by the tidal field of a binary companion.Comment: 9 Latex pages, 14 postscript figure
The Inheritance of Resistance Alleles in Multiple Sclerosis
Multiple sclerosis (MS) is a complex trait in which alleles at or near the class II loci HLA-DRB1 and HLA-DQB1 contribute significantly to genetic risk. HLA-DRB1*15 and HLA-DRB1*17-bearing haplotypes and interactions at the HLA-DRB1 locus increase risk of MS but it has taken large samples to identify resistance HLA-DRB1 alleles. In this investigation of 7,093 individuals from 1,432 MS families, we have assessed the validity, mode of inheritance, associated genotypes, and the interactions of HLA-DRB1 resistance alleles. HLA-DRB1*14-, HLA-DRB1*11-, HLA-DRB1*01-, and HLA-DRB1*10-bearing haplotypes are protective overall but they appear to operate by different mechanisms. The first type of resistance allele is characterised by HLA-DRB1*14 and HLA-DRB1*11. Each shows a multiplicative mode of inheritance indicating a broadly acting suppression of risk, but a different degree of protection. In contrast, a second type is exemplified by HLA-DRB1*10 and HLA-DRB1*01. These alleles are significantly protective when they interact specifically in trans with HLA-DRB1*15-bearing haplotypes. HLA-DRB1*01 and HLA-DRB1*10 do not interact with HLA-DRB1*17, implying that several mechanisms may be operative in major histocompatibility complex–associated MS susceptibility, perhaps analogous to the resistance alleles. There are major practical implications for risk and for the exploration of mechanisms in animal models. Restriction of antigen presentation by HLA-DRB1*15 seems an improbably simple mechanism of major histocompatibility complex–associated susceptibility
An Extremes of outcome strategy provides evidence that multiple sclerosis severity is determined by alleles at the <i>HLA-DRB1</i> locus
Multiple sclerosis (MS) is a common inflammatory disease of the
central nervous system unsurpassed for variability in disease outcome.
A cohort of sporadic MS cases (n=63), taken from opposite
extremes of the distribution of long-term outcome, was used to
determine the role of the HLA-DRB1 locus on MS disease severity.
Genotyping sets of benign and malignant MS patients showed that
HLA-DRB1*01 was significantly underrepresented in malignant
compared with benign cases. This allele appears to attenuate the
progressive disability that characterizes MS in the long term. The
observation was doubly replicated in (i) Sardinian benign and
malignant patients and (ii) a cohort of affected sibling pairs
discordant for HLA-DRB1*01. Among the latter, mean disability
progression indices were significantly lower in those carrying the
HLA-DRB1*01 allele compared with their disease-concordant siblings
who did not. The findings were additionally supported by
similar transmission distortion of HLA-DRB1*04 subtypes closely
related to HLA-DRB1*01. The protective effect of HLA-DRB1*01 in
sibling pairs may result from a specific epistatic interaction with the
susceptibility allele HLA-DRB1*1501. A high-density (>700) SNP
examination of the MHC region in the benign and malignant
patients could not identify variants differing significantly between
the two groups, suggesting that HLA-DRB1 may itself be the
disease-modifying locus. We conclude that HLA-DRB1*01, previously
implicated in disease resistance, acts as an independent
modifier of disease progression. These results closely link susceptibility
to long-term outcome in MS, suggesting that shared quantitative
MHC-based mechanisms are common to both, emphasizing
the central role of this region in pathogenesis
Mood instability and psychosis : analyses of British national survey data
Background: We used British national survey data to test specific hypotheses that mood instability (1) is associated with psychosis and individual psychotic phenomena, (2) predicts the later emergence of auditory hallucinations and paranoid ideation, and (3) mediates the link between child sexual abuse and psychosis. Methods: We analyzed data from the 2000 and 2007 UK national surveys of psychiatric morbidity (N = 8580 and 7403, respectively). The 2000 survey included an 18-month follow-up of a subsample (N = 2406). Mood instability was assessed from the Structured Clinical Interview for DSM-IV Axis II (SCID-II) questionnaire. Our dependent variables comprised auditory hallucinations, paranoid ideation, the presence of psychosis overall, and a 15-item paranoia scale. Results: Mood instability was strongly associated in cross-sectional analyses with psychosis (2000: OR: 7.5; 95% CI: I 4.1–13.8; 2007: OR: 21.4; CI: 9.7–41.2), paranoid ideation (2000: OR: 4.7; CI: 4.1–5.4; 2007: OR: 5.7; CI: 4.9–6.7), auditory hallucinations (2000: OR: 3.4; CI: 2.6–4.4; 2007: OR 3.5; CI: 2.7–4.7), and paranoia total score (2000: Coefficient: 3.6; CI: 3.3–3.9), remaining so after adjustment for current mood state. Baseline mood instability significantly predicted 18-month inceptions of paranoid ideation (OR: 2.3; CI: 1.6–3.3) and of auditory hallucinations (OR: 2.6; CI: 1.5–4.4). Finally, it mediated a third of the total association of child sexual abuse with psychosis and persecutory ideation and a quarter of that with auditory hallucinations. Conclusions: Mood instability is a prominent feature of psychotic experience and may have a role in its genesis. Targeting mood instability could lead to innovative treatments for psychosis
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