2,763 research outputs found
Temporal Dynamics of Hypothesis Generation: The Influences of Data Serial Order, Data Consistency, and Elicitation Timing
The pre-decisional process of hypothesis generation is a ubiquitous cognitive faculty that we continually employ in an effort to understand our environment and thereby support appropriate judgments and decisions. Although we are beginning to understand the fundamental processes underlying hypothesis generation, little is known about how various temporal dynamics, inherent in real world generation tasks, influence the retrieval of hypotheses from long-term memory. This paper presents two experiments investigating three data acquisition dynamics in a simulated medical diagnosis task. The results indicate that the mere serial order of data, data consistency (with previously generated hypotheses), and mode of responding influence the hypothesis generation process. An extension of the HyGene computational model endowed with dynamic data acquisition processes is forwarded and explored to provide an account of the present data
Toward an Understanding of the Economics of Charity: Evidence from a Field Experiment
This study develops theory and uses a door-to-door fundraising field experiment to explore the economics of charity. We approached nearly 5000 households, randomly divided into four experimental treatments, to shed light on key issues on the demand side of charitable fundraising. Empirical results are in line with our theory: in gross terms, our lottery treatments raised considerably more money than our voluntary contributions treatments. Interestingly, we find that a one standard deviation increase in female solicitor physical attractiveness is similar to that of the lottery incentive¡ªthe magnitude of the estimated difference in gifts is roughly equivalent to the treatment effect of moving from our theoretically most attractive approach (lotteries) to our least attractive approach (voluntary contributions).
Hypothesis Generation: Temporal Dynamics
In order to bring structure to many of the judgment and decision making problems people encounter, decision makers are often required to generate, from memory, hypotheses explaining their observations. This dissertation focuses on this predecisional process of hypothesis generation which underlies and supports much judgment and decision making behavior. Although we are beginning to understand a great deal about the mechanisms governing the generation and utilization of hypotheses (Thomas, R.P. et al. 2008) more work is needed to fully appreciate how these retrieval, judgment, and choice processes operate in real-world task environments.The present research addresses temporal dynamics underlying hypothesis generation processes. As temporal dynamics are an inevitable precondition for information acquisition and utilization, a full understanding of hypothesis generation processes will remain speculative without systematic examination of the influences of such dynamics. Four experiments examined various pertinent issues in an effort to provide fundamental insights upon which more complete theory can be developed. The influence of information order, information activation in working memory, information agreement, information use (grouped vs. isolated), and working memory allocation were examined. Furthermore, two novel methodologies are forwarded providing unique approaches for assessing the active contents of working memory through time. By exploiting biases in which visual attention is drawn towards items matching the contents of working memory these measures are able to index the current contents of working memory at any given point in time.Several critical findings emerged from this set of experiments. First, results indicate that people tend to weight later information more heavily than earlier information in some, but not all, circumstances. Second, the role of information activation in working memory was implicated as governing its contribution to the hypothesis generation processes wherein more active items contribute more. Third, it was found that the acquisition of information that is inconsistent with hypotheses under consideration causes people to discard these inconsistent hypotheses. This work provides important insights into how internal working memory dynamics interact with external dynamics in shaping the hypothesis generation process that can be used to support the development of a comprehensive computational theory
Upcycling by Crowdsourcing: Leveraging Pro-Environmental Behavior as Corporate Strategy
This report provides a critique of Company X's strategy of reliance on vol-
unteer organizations and makes recommendations to support and improve
its collection operations. We used focus-group interviews and a national
email survey of volunteer leaders to determine the motivating factors for
joining and participating in the program. Our results show that 68% of
collection sites are located in schools and that schools are the most pro-
ductive sites. Most non-school collection sites are primarily female. There
are two leading motivational factors for sites: nancial rewards and con-
cern for the environment, and site o cials would like to be able to share
best practices with each other. Anecdotally, collection site o cials are
frustrated by Company X's customer service and by the long waitlists for
the more popular waste items. We recommend that Company X focus in
the short-term on increasing its volunteer productivity through improved
customer service, by providing volunteer groups a platform with which
to communicate with one another, and by sharing speci c volunteer de-
mographics with CPG brand partners. In the medium-term, Company
X should focus on enhancing its environmental message and diversifying
volunteer demographics, and in the long-term, should consider how best
to modify its business model in moving forward to nd alternative ways
of financing Squads.Master of ScienceNatural Resources and EnvironmentUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/90949/4/TC_FINAL_7-May-2012.pd
A Parimutuel Market Microstructure for Contingent Claims Trading
A parimutuel market microstructure for contingent claims trading is
proposed and analyzed. A parimutuel microstructure is a call auction
where relative equilibrium prices of contingent claims are endogenously
determined using a specific mechanism. We propose a market
microstructure incorporating parimutuel principles which provides for
notional derivatives transactions, limit orders, and bundling of
contingent claims across states. This microstructure will be used by
Longitude Inc.'s clients to transact derivatives on economic statistics,
weather, insurance losses and other types of risks. JPMorgan Chase and
Deutsche Bank are some of the financial institutions that will be
holding parimutuel auctions in early 2002
Post-translational Protein Deimination in Cod (Gadus morhua L.) Ontogeny: Novel Roles in Tissue Remodelling and Mucosal Immune Defences?
Peptidylarginine deiminases (PADs) are calcium dependent enzymes with physiological and pathophysiological roles conserved throughout phylogeny. PADs promote post-translational deimination of protein arginine to citrulline, altering the structure and function of target proteins. Deiminated proteins were detected in the early developmental stages of cod from 11 days post fertilisation to 70 days post hatching. Deiminated proteins were present in mucosal surfaces and in liver, pancreas, spleen, gut, muscle, brain and eye during early cod larval development. Deiminated protein targets identified in skin mucosa included nuclear histones; cytoskeletal proteins such as tubulin and beta-actin; metabolic and immune related proteins such as galectin, mannan-binding lectin, toll-like receptor, kininogen, Beta2-microglobulin, aldehyde dehydrogenase, bloodthirsty and preproapolipoprotein A-I. Deiminated histone H3, a marker for anti-pathogenic neutrophil extracellular traps, was particularly elevated in mucosal tissues in immunostimulated cod larvae. PAD-mediated protein deimination may facilitate protein moonlighting, allowing the same protein to exhibit a range of biological functions, in tissue remodelling and mucosal immune defences in teleost ontogeny
Pentraxins CRP-I and CRP-II are post-translationally deiminated and differ in tissue specificity in cod (Gadus morhua L.) ontogeny
Pentraxins are fluid phase pattern recognition molecules that form an important part of the innate immune defence and are conserved between fish and human. In Atlantic cod (Gadus morhua L.), two pentraxin-like proteins have been described, CRP-I and CRP-II. Here we show for the first time that these two CRP forms are post-translationally deiminated (an irreversible conversion of arginine to citrulline) and differ with respect to tissue specific localisation in cod ontogeny from 3 to 84 days post hatching. While both forms are expressed in liver, albeit at temporally differing levels, CRP-I shows a strong association with nervous tissue while CRP-II is strongly associated to mucosal tissues of gut and skin. This indicates differing roles for the two pentraxin types in immune responses and tissue remodelling, also elucidating novel roles for CRP-I in the nervous system. The presence of deimination positive bands for cod CRPs varied somewhat between mucus and serum, possibly facilitating CRP protein moonlighting, allowing the same protein to exhibit a range of biological functions and thus meeting different functional requirements in different tissues. The presented findings may further current understanding of the diverse roles of pentraxins in teleost immune defences and tissue remodelling, as well as in various human pathologies, including autoimmune diseases, amyloidosis and cancer
Using MOST to reveal the secrets of the mischievous Wolf-Rayet binary CV Ser
The WR binary CV Serpentis (= WR113, WC8d + O8-9IV) has been a source of
mystery since it was shown that its atmospheric eclipses change with time over
decades, in addition to its sporadic dust production. The first high-precision
time-dependent photometric observations obtained with the MOST space telescope
in 2009 show two consecutive eclipses over the 29d orbit, with varying depths.
A subsequent MOST run in 2010 showed a seemingly asymmetric eclipse profile. In
order to help make sense of these observations, parallel optical spectroscopy
was obtained from the Mont Megantic Observatory (2009, 2010) and from the
Dominion Astrophysical Observatory (2009). Assuming these depth variations are
entirely due to electron scattering in a beta-law wind, an unprecedented 62%
increase in mass-loss rate is observed over one orbital period. Alternatively,
no change in mass-loss rate would be required if a relatively small fraction of
the carbon ions in the wind globally recombined and coaggulated to form carbon
dust grains. However, it remains a mystery as to how this could occur. There
also seems to be evidence for the presence of corotating interaction regions
(CIR) in the WR wind: a CIR-like signature is found in the light curves,
implying a potential rotation period for the WR star of 1.6 d. Finally, a new
circular orbit is derived, along with constraints for the wind collision.Comment: 11 pages, 11 figures, 5 table
Peptidylarginine Deiminases Post-Translationally Deiminate Prohibitin and Modulate Extracellular Vesicle Release and MicroRNAs in Glioblastoma Multiforme.
Glioblastoma multiforme (GBM) is the most aggressive form of adult primary malignant brain tumour with poor prognosis. Extracellular vesicles (EVs) are a key-mediator through which GBM cells promote a pro-oncogenic microenvironment. Peptidylarginine deiminases (PADs), which catalyze the post-translational protein deimination of target proteins, are implicated in cancer, including via EV modulation. Pan-PAD inhibitor Cl-amidine affected EV release from GBM cells, and EV related microRNA cargo, with reduced pro-oncogenic microRNA21 and increased anti-oncogenic microRNA126, also in combinatory treatment with the chemotherapeutic agent temozolomide (TMZ). The GBM cell lines under study, LN18 and LN229, differed in PAD2, PAD3 and PAD4 isozyme expression. Various cytoskeletal, nuclear and mitochondrial proteins were identified to be deiminated in GBM, including prohibitin (PHB), a key protein in mitochondrial integrity and also involved in chemo-resistance. Post-translational deimination of PHB, and PHB protein levels, were reduced after 1 h treatment with pan-PAD inhibitor Cl-amidine in GBM cells. Histone H3 deimination was also reduced following Cl-amidine treatment. Multifaceted roles for PADs on EV-mediated pathways, as well as deimination of mitochondrial, nuclear and invadopodia related proteins, highlight PADs as novel targets for modulating GBM tumour communication
Peptidylarginine deiminase and deiminated proteins are detected throughout early halibut ontogeny - Complement components C3 and C4 are post-translationally deiminated in halibut (Hippoglossus hippoglossus L.)
Post-translational protein deimination is mediated by peptidylarginine deiminases (PADs), which are calcium dependent enzymes conserved throughout phylogeny with physiological and pathophysiological roles. Protein deimination occurs via the conversion of protein arginine into citrulline, leading to structural and functional changes in target proteins. In a continuous series of early halibut development from 37 to 1050° d, PAD, total deiminated proteins and deiminated histone H3 showed variation in temporal and spatial detection in various organs including yolksac, muscle, skin, liver, brain, eye, spinal cord, chondrocytes, heart, intestines, kidney and pancreas throughout early ontogeny. For the first time in any species, deimination of complement components C3 and C4 is shown in halibut serum, indicating a novel mechanism of complement regulation in immune responses and homeostasis. Proteomic analysis of deiminated target proteins in halibut serum further identified complement components C5, C7, C8 C9 and C1 inhibitor, as well as various other immunogenic, metabolic, cytoskeletal and nuclear proteins. Post-translational deimination may facilitate protein moonlighting, an evolutionary conserved phenomenon, allowing one polypeptide chain to carry out various functions to meet functional requirements for diverse roles in immune defences and tissue remodelling
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