155 research outputs found
TRICHOTOMOUS CHOICE: A POSSIBLE SOLUTION TO DUAL RESPONSE OBJECTIVES IN DICHOTOMOUS CHOICE CONTINGENT VALUATION QUESTIONS
We investigate the possibility that some respondents to a dichotomous choice question vote YES, even though they would not pay the posted dollar amount in order to register support for the project or policy. A trichotomous choice question format is proposed to determine if allowing respondents the opportunity to vote in favor of a project at an amount less than their bid affects estimated willingness to pay. Using univariate and multivariate tests, we find the trichotomous choice question format reduces the number of YES responses and produces a statistically significant decrease in willingness to pay for an open-space program.Research Methods/ Statistical Methods,
Legendrian Torus and Cable Links
We give a classification of Legendrian torus links. Along the way, we give
the first classification of infinite families of Legendrian links where some
smooth symmetries of the link cannot be realized by Legendrian isotopies. We
also give the first family of links that are non-destabilizable but do not have
maximal Thurston-Bennequin invariant and observe a curious distribution of
Legendrian torus knots that can be realized as the components of a Legendrian
torus link. This classification of Legendrian torus links leads to a
classification of transversal torus links.
We also give a classification of Legendrian and transversal cable links of
knot types that are uniformly thick and Legendrian simple. Here we see some
similarities with the classification of Legendrian torus links but also some
differences. In particular, we show that there are Legendrian representatives
of cable links of any uniformly thick knot type for which no symmetries of the
components can be realized by a Legendrian isotopy, others where only cyclic
permutations of the components can be realized, and yet others where all smooth
symmetries are realizable.Comment: 67 pages, 19 figure
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March 1964
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Better turf through research and Educatio
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Turf Management Club by John Traynor (page 1) Who Is Superintendent Here by H.E. Frenette (1) Good Turf Can Result from good Sodding (3) Golf Course Superintendent by Edwart Wiacek (4) Picture - Outstanding Senior Prof. Troll Picture - recognition for Blazers St. Andrew\u27s, Scotland by William Hynd (5) Analogy of a Turf Manager by James B. Cole (6) Fish Trouble by Peter A. Langelier and Dennis P. Leger (8) Square Rings by Robert P. McGuire (9) A Different Type of Course by Robert Hall (10) Literature by Pierre Coste (11) Weeds in Golf Course Turf and Their Control by John F. Cornman (A-1) The USe of Liquid Fertilizer by Anthony B. Longo (A-3) Fertilizing a Golf Course Through an Irrigation System by Herbert E. Berg (A-6) The Extent of Winter Injury on Golf Courses by James L. Holmes (A-11) The Problem of Winter Injury by James B. Beard (A-13) Establishing, Maintaining, and Selling Sod for Turf Areas in New England by George F. Stewart (A-20) Problems of Maintaining Turf Around Industrial Grounds by George Moore (A-22) Landscaping Industrial sites by A.W. Boicourt (A-25) Introduction to the panel Discussion on Grasses for Tees and Their Management by Alexander M. Radko (A-28) Building a Golf Tee by Phil Cassidy (A-29) Grasses for Tees and Their Management by Wm. Dest (A-31) Golf Course Tee maintenance by Jim Fulwider (A-32) Tees by F. Thompson (A-33) How to Draw up a Contract by Lawrence D. Rhoades (A-34) My Contract by Lucien E. Duval (A-37) The Golf Car Problem by Geoffrey S. Cornish (A-41) Golf Cars and Turfgrass by Lee Record (A-42) Course Design and Golf Cars by William F. Mitchell (A-42) Golf Cars and the Established Course by Sherwood Moore (A-45) Course Design and Golf Cars by Phil Wogan (a-52) Introduction of Cars to the New Course by M. Ovian (A-56
The Intriguing Effects of Substituents in the N-Phenethyl Moiety of Norhydromorphone: A Bifunctional Opioid from a Set of âTail Wags Dogâ Experiments
This work is licensed under a Creative Commons Attribution 4.0 International License.(â)-N-Phenethyl analogs of optically pure N-norhydromorphone were synthesized and pharmacologically evaluated in several in vitro assays (opioid receptor binding, stimulation of [35S]GTPÎłS binding, forskolin-induced cAMP accumulation assay, and MOR-mediated ÎČ-arrestin recruitment assays). âBodyâ and âtailâ interactions with opioid receptors (a subset of Portogheseâs message-address theory) were used for molecular modeling and simulations, where the âaddressâ can be considered the âbodyâ of the hydromorphone molecule and the âmessageâ delivered by the substituent (tail) on the aromatic ring of the N-phenethyl moiety. One compound, N-p-chloro-phenethynorhydromorphone ((7aR,12bS)-3-(4-chlorophenethyl)-9-hydroxy-2,3,4,4a,5,6-hexahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinolin-7(7aH)-one, 2i), was found to have nanomolar binding affinity at MOR and DOR. It was a potent partial agonist at MOR and a full potent agonist at DOR with a ÎŽ/ÎŒ potency ratio of 1.2 in the ([35S]GTPÎłS) assay. Bifunctional opioids that interact with MOR and DOR, the latter as agonists or antagonists, have been reported to have fewer side-effects than MOR agonists. The p-chlorophenethyl compound 2i was evaluated for its effect on respiration in both mice and squirrel monkeys. Compound 2i did not depress respiration (using normal air) in mice or squirrel monkeys. However, under conditions of hypercapnia (using air mixed with 5% CO2), respiration was depressed in squirrel monkeys.NIDA grant P30 DA13429NIDA grant DA039997NIDA grant DA018151NIDA grant DA035857NIDA grant DA047574NIH Intramural Research Programs of the National Institute on Drug AbuseNational Institute of Alcohol Abuse and AlcoholismNIH Intramural Research Programs of the National Institute on Drug AbuseNIH Intramural Research Program through the Center for Information TechnologyNIH Intramural Research Programs of the National Institute on Drug Abus
First observation of Bs -> D_{s2}^{*+} X mu nu decays
Using data collected with the LHCb detector in proton-proton collisions at a
centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and
Bs -> D0 K+ X mu nu are detected. Two structures are observed in the D0 K+ mass
spectrum at masses consistent with the known D^+_{s1}(2536) and
$D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to the
total Bs semileptonic rate are B(Bs -> D_{s2}^{*+} X mu nu)/B(Bs -> X mu nu)=
(3.3\pm 1.0\pm 0.4)%, and B(Bs -> D_{s1}^+ X munu)/B(Bs -> X mu nu)= (5.4\pm
1.2\pm 0.5)%, where the first uncertainty is statistical and the second is
systematic. This is the first observation of the D_{s2}^{*+} state in Bs
decays; we also measure its mass and width.Comment: 8 pages 2 figures. Published in Physics Letters
Integration of GWAS SNPs and tissue specific expression profiling reveal discrete eQTLs for human traits in blood and brain
Our knowledge of the transcriptome has become much more complex since the days of
the central dogma of molecular biology. We now know that splicing takes place to
create potentially thousands of isoforms from a single gene, and we know that RNA
does not always faithfully recapitulate DNA if RNA editing occurs. Collectively, these
observations show that the transcriptome is amazingly rich with intricate regulatory
mechanisms for overall gene expression, splicing, and RNA editing.
Genetic variability can play a role in controlling gene expression, which can be
identified by examining expression quantitative trait loci (eQTLs). eQTLs are genomic
regions where genetic variants, including single nucleotide polymorphisms (SNPs)
show a statistical association with expression of mRNA transcripts. In humans, many
SNPs are also associated with disease, and have been identified using genome wide
association studies (GWAS) but the biological effects of those SNPs are usually not
known. If SNPs found in GWAS are also found in eQTLs, then one could hypothesize
that expression levels may contribute to disease risk. Performing eQTL analysis with
GWAS SNPs in both blood and brain, specifically the frontal cortex and the
cerebellum, we found both shared and tissue unique eQTLS. The identification of
tissue-unique eQTLs supports the argument that choice of tissue type is important in
eQTL studies (Paper I).
Aging is a complex process with the mechanisms underlying aging still being poorly
defined. There is evidence that the transcriptome changes with age, and hence we used
the brain dataset from our first paper as a discovery set, with an additional replication
dataset, to investigate any aging-gene expression associations. We found evidence that
many genes were associated with aging. We further found that there were more
statically significant expression changes in the frontal cortex versus the cerebellum,
indicating that brain regions may age at different rates. As the brain is a heterogeneous
tissue including both neurons and non-neuronal cells, we used LCM to capture Purkinje
cells as a representative neuronal type and repeated the age analysis. Looking at the
discovery, replication and Purkinje cell datasets we found five genes with strong,
replicated evidence of age-expression associations (Paper II).
Being able to capture and quantify the depth of the transcriptome has been a lengthy
process starting with methods that could only measure a single gene to genome-wide
techniques such as microarray. A recently developed technology, RNA-Seq, shows
promise in its ability to capture expression, splicing, and editing and with its broad
dynamic range quantification is accurate and reliable. RNA-Seq is, however, data
intensive and a great deal of computational expertise is required to fully utilize the
strengths of this method. We aimed to create a small, well-controlled, experiment in
order to test the performance of this relatively new technology in the brain. We chose
embryonic versus adult cerebral cortex, as mice are genetically homogenous and there
are many known differences in gene expression related to brain development that we
could use as benchmarks for analysis testing. We found a large number of differences
in total gene expression between embryonic and adult brain. Rigorous technical and
biological validation illustrated the accuracy and dynamic range of RNA-Seq. We were also able to interrogate differences in exon usage in the same dataset. Finally we
were able to identify and quantify both well-known and novel A-to-I edit sites. Overall
this project helped us develop the tools needed to build usable pipelines for RNA-Seq
data processing (Paper III).
Our studies in the developing brain (Paper III) illustrated that RNA-Seq was a useful
unbiased method for investigating RNA editing. To extend this further, we utilized a
genetically modified mouse model to study the transcriptomic role of the RNA editing
enzyme ADAR2. We found that ADAR2 was important for editing of the coding
region of mRNA as a large proportion of RNA editing sites in coding regions had a
statistically significant decrease in editing percentages in Adar2
-/-Gria2
R/R
mice versus
controls. However, despite indications in the literature that ADAR2 may also be
involved in splicing and expression regulatory machinery we found no changes in gene
expression or exon utilization in Adar2
-/-Gria2
R/R
mice as compared to their littermate
controls (Paper IV).
In our final study, based on the methods developed in Papers III and IV, we revisited
the idea of age related gene expression associations from Paper II. We used a subset of
human frontal cortices for RNA sequencing. Interestingly we found more gene
expression changes with aging compared to the previous data using microarrays in
Paper II. When the significant gene lists were analysed for gene ontology enrichment,
we found that there was a large number of downregulated genes involved in synaptic
function while those that were upregulated had enrichment in immune function. This
dataset illustrates that the aging brain may be predisposed to the processes found in
neurodegenerative diseases (Paper V)
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Prion-like domain mutations in hnRNPs cause multisystem proteinopathy and ALS
Summary Algorithms designed to identify canonical yeast prions predict that ~250 human proteins, including several RNA-binding proteins associated with neurodegenerative disease, harbor a distinctive prion-like domain (PrLD) enriched in uncharged polar amino acids and glycine. PrLDs in RNA-binding proteins are essential for the assembly of ribonucleoprotein granules. However, the interplay between human PrLD function and disease is not understood. Here, we define pathogenic mutations in PrLDs of hnRNPA2/B1 and hnRNPA1 in families with inherited degeneration affecting muscle, brain, motor neuron and bone, and a case of familial ALS. Wild-type hnRNPA2 and hnRNPA1 display an intrinsic tendency to assemble into self-seeding fibrils, which is exacerbated by the disease mutations. Indeed, the pathogenic mutations strengthen a âsteric zipperâ motif in the PrLD, which accelerates formation of self-seeding fibrils that cross-seed polymerization of wild-type hnRNP. Importantly, the disease mutations promote excess incorporation of hnRNPA2 and hnRNPA1 into stress granules and drive the formation of cytoplasmic inclusions in animal models that recapitulate the human pathology. Thus, dysregulated polymerization caused by a potent mutant âsteric zipperâ motif in a PrLD can initiate degenerative disease. Related proteins with PrLDs must be considered candidates for initiating and perhaps propagating proteinopathies of muscle, brain, motor neuron and bone
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