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Aggregates of many judgments tend to outperform each of the individual judgments that compose the aggregate, termed the Wisdom of Crowds effect. Metacognition has played an understudied role in the efficacy of these crowds and so in a series of experiments I explore how metacognition and self-direction can be used to improve crowd wisdom. I first demonstrate empirically that individuals can leverage their metacognitive abilities to improve the performance of crowds when they are allowed to opt-in to questions of their choosing. I develop a Bayesian framework wherein latent contextual knowledge describes how crowd members make opt-in decisions to elucidate the relationship between these cognitive and metacognitive processes. I then show that metacognitive ability can be estimated by asking questions with no correct response options and create metacognitively wise crowds which achieve more accurate responses despite incorporating fewer crowd members. I discuss my contributions to a geopolitical forecasting competition in which I developed models that combine human and algorithmic judgments to create highly accurate forecasts of the future. In this competition, I evaluated the effects of attenuating forecaster self-direction in an applied setting. These findings collectively demonstrate the importance of metacognition in forming accurate aggregate judgments and clarify the underlying metacognitive processes involved in self-direction.

In many ecologically situated cognitive tasks, participants en-gage in self-selection of the particular stimuli they choose toevaluate or test themselves on. This contrasts with a traditionalexperimental approach in which an experimenter has completecontrol over the participant’s experience. Considering thesetwo situations jointly provides an opportunity to understandwhy participants opt in to some stimuli or tasks but not toothers. We present here a Bayesian model of cognitive andmetacognitive processes that uses latent contextual knowledgeto model how learners use knowledge to make opt-in decisions.We leverage the model to describe how performance on self-selected stimuli relates to performance on true experimentaltasks that deny learners the opportunity for self-selection. Weillustrate the utility of the approach with an application to ageneral-knowledge answering task.

Patients with pulmonary hypertension associated with congenital heart disease survive longer with preserved right ventricular (RV) function compared with those with primary pulmonary hypertension. The purpose of this study was to test the hypothesis that superior RV performance can be demonstrated, at baseline and when challenged with increased RV afterload, in lambs with chronic left-to-right cardiac shunts compared with control lambs. A shunt was placed between the pulmonary artery and the aorta in fetal lambs (shunt). RV pressure-volume loops were obtained 4 wk after delivery in shunt and control lambs, before and after increased afterload was applied using pulmonary artery banding (PAB). Baseline stroke volume (8.7 ± 1.8 vs. 15.8 ± 2.7 ml, P = 0.04) and cardiac index (73.0 ± 4.0 vs. 159.2 ± 25.1 ml·min(-1)·kg(-1), P = 0.02) were greater in shunts. After PAB, there was no difference in the change in cardiac index (relative to baseline) between groups; however, heart rate (HR) was greater in controls (168 ± 7.3 vs. 138 ± 6.6 beats/min, P = 0.01), and end-systolic elastance (Ees) was greater in shunts (2.63 vs. 1.31 × baseline, P = 0.02). Control lambs showed decreased mechanical efficiency (71% baseline) compared with shunts. With acute afterload challenge, both controls and shunts maintained cardiac output; however, this was via maladaptive responses in controls, while shunts maintained mechanical efficiency and increased contractility via a proposed enhanced Anrep effect-the second, slow inotropic response in the biphasic ventricular response to increased afterload, a novel finding in the RV. The mechanisms related to these physiological differences may have important therapeutic implications.

We have previously shown decreased pulmonary lymph flow in our lamb model of chronically increased pulmonary blood flow, created by the in utero placement of an 8-mm aortopulmonary shunt. The purpose of this study was to test the hypothesis that abnormal lymphatic function in shunt lambs is due to impaired lymphatic endothelial nitric oxide (NO)-cGMP signaling resulting in increased lymphatic vascular constriction and/or impaired relaxation. Thoracic duct rings were isolated from 4-wk-old shunt (n = 7) and normal (n = 7) lambs to determine length-tension properties, vascular reactivity, and endothelial NO synthase protein. At baseline, shunt thoracic duct rings had 2.6-fold higher peak to peak tension and a 2-fold increase in the strength of contractions compared with normal rings (P < 0.05). In response to norepinephrine, shunt thoracic duct rings had a 2.4-fold increase in vascular tone compared with normal rings (P < 0.05) and impaired relaxation in response to the endothelium-dependent dilator acetylcholine (63% vs. 13%, P < 0.05). In vivo, inhaled NO (40 ppm) increased pulmonary lymph flow (normalized for resistance) ∼1.5-fold in both normal and shunt lambs (P < 0.05). Inhaled NO exposure increased bioavailable NO [nitrite/nitrate (NOx); ∼2.5-fold in normal lambs and ∼3.4-fold in shunt lambs] and cGMP (∼2.5-fold in both) in the pulmonary lymph effluent (P < 0.05). Chronic exposure to increased pulmonary blood flow is associated with pulmonary lymphatic endothelial injury that disrupts NO-cGMP signaling, leading to increased resting vasoconstriction, increased maximal strength of contraction, and impaired endothelium-dependent relaxation. Inhaled NO increases pulmonary lymph NOx and cGMP levels and pulmonary lymph flow in normal and shunt lambs. Therapies that augment NO-cGMP signaling within the lymphatic system may provide benefits, warranting further study.

Flea-borne typhus has emerged as an important vector-borne disease in Los Angeles and Orange Counties, California, with over 400 human cases having been reported since the mid-1980s. In Orange County alone, 127 human cases have been investigated by the Orange County Vector Control District since 2006. Results from a collaborative study with the Centers for Disease Control and Prevention from 2006-2008 identified the suburban cycle of flea-borne typhus transmission (backyard wildlife/pets – fleas – humans) in Los Angeles and Orange counties. Free-ranging feral and companion cats and the Virginia opossum were identified as the primary host animals of the cat flea, the insect vector responsible for maintenance and transmission of the etiologic agents, Rickettsia typhi and R. felis, for disease in humans. Although the causes of the increase in human flea-borne typhus cases are not well-defined, this rise has been accompanied by changes in how public and privately-sponsored animal control groups manage nuisance animal populations in the affected southern California counties. Instead of elimination through euthanasia of unwanted feral cats and non-native opossums, rehabilitation, relocation, and “no-trap” policies have become the preferred practice of local animal control agencies. The public health obligation for which governmental animal control agencies were created must be re-emphasized as one way of preventing further outbreaks of flea-borne typhus infections in Orange County and the surrounding California counties.

We study the two-dimensional space of supergravity solutions corresponding to non-supersymmetric deformations of the baryonic branch of Klebanov-Strassler. By combining analytical methods with a numerical survey of the parameter space, we find that this solution space includes as limits the softly-broken N=1 solutions of Gubser et al. and those of Dymarsky and Kuperstein. We also identify a one-dimensional family of solutions corresponding to a natural non-supersymmetric generalisation of Klebanov-Strassler, and one corresponding to the limit in which supersymmetry is completely absent, even in the far UV. For almost all of the parameter space we find indications that much of the structure of the supersymmetric baryonic branch survives., Comment: 29 pages plus appendices, 11 figures

IntroductionNecrotizing enterocolitis (NEC) is a devastating disease of premature infants. Probiotics decrease the risk of NEC in clinical and experimental studies. Antimicrobial peptides protect the gut against noxious microbes and shape the commensal microbiota, but their role in NEC remains unclear.MethodsTo investigate the expression of antimicrobial peptides in experimental NEC and the impact of probiotics on their expression, premature rats were divided into three groups: dam fed (DF), hand fed with formula (FF), or hand fed with formula containing Bifidobacterium bifidum (FF + BIF). All groups were exposed to asphyxia and cold stress.ResultsLike in human ontogeny, the rat pup has low expression of Paneth cell antimicrobials, which increases rapidly during normal development. The expression of lysozyme, secretory phospholipase A(2) (sPLA(2)), pancreatic-associated proteins 1 and 3 mRNA was elevated in the FF group with a high incidence of NEC, as compared with the DF and FF + BIF groups where the disease was attenuated.DiscussionWe conclude that induction of antimicrobial peptides occurs in experimental NEC similar to that reported in human disease and is attenuated when disease is averted by probiotic B. bifidum. The induction of antimicrobial peptides is likely an adaptive mucosal response that is often not sufficient to prevent disease in the premature gut.

We study a non-supersymmetric deformation of the field theory dual to the baryonic branch of Klebanov-Strassler. Using a combination of analytical (series expansions) and numerical methods we construct non-supersymmetric backgrounds that smoothly interpolate between the desired UV and IR behaviors. We calculate various observables of the field theory and propose a picture of soft breaking by gaugino masses that is consistent with the various calculations on the string side., Comment: 32 pages plus many appendixes. One figure

We calculate quark-antiquark potentials using the relationship between the expectation value of the Wilson loop and the action of a probe string in the string dual. We review and categorize the possible forms of the dependence of the energy on the separation between the quarks. In particular, we examine the possibility of there being a minimum separation for probe strings which do not penetrate close to the origin of the bulk space, and derive a condition which determines whether this is the case. We then apply these considerations to the flavoured resolved deformed conifold background of Gaillard et al. We suggest that the unusual behaviour we observe in this solution is likely to be related to the IR singularity which is not present in the unflavoured case.

Full Text, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), Department of Marketing, Griffith Business School, The social and economic contribution of franchising to many Western economies is widely reported (Alon, 2004). Franchising is a business model in which a franchisee is granted the right to engage in offering, selling, or distributing goods or services under a marketing system that has been designed by the franchisor (Justis and Judd, 2004). The franchisor permits the franchisee to use the franchisor’s trade name and advertising (Mendelsohn, 2004). The Australian franchising sector has achieved consistent growth since the 1980s, with franchising activity currently contributing approximately (12 percent) of the country’s gross domestic product (Frazer et al., 2008). However, research has revealed that franchising systems may be unable to expand at the rate they desire owing to difficulties in obtaining franchisee finance and a shortage of suitable franchisee applicants (Price Waterhouse Coopers, 2009; Frazer et al., 2008). There are currently 56,200 business format franchised units operating in Australia (Frazer et al., 2008), accounting for approximately (5 percent) of all small business in Australia (ABS, 2009). Though this appears to suggest that franchising has the potential to expand, prior research has shown that the lack of available suitable franchisee candidates may constrain system growth and sector expansion (Frazer et al., 2008). Previous research shows that this is not a recent phenomenon (Knight, 1986; McGuire, 1971) and may be reliant upon how franchisors classify attributes that are desirable in potential incumbent franchisees (Frazer and McCosker, 1999; Hedricks and Kiefer, 2005; Michael, 2003). However, there appears to be a gap in our current understanding of how these impediments to franchise growth may be overcome. In addition to acquiring valuable insights into current recruitment practice, the primary purpose of this research is to sustain informed decision-making in the future through a study of the fundamental and under-researched question of

The social and economic contribution of franchising to many Western economies is widely reported (Alon, 2004). Franchising is a business model in which a franchisee is granted the right to engage in offering, selling, or distributing goods or services under a marketing system that has been designed by the franchisor (Justis and Judd, 2004). The franchisor permits the franchisee to use the franchisor’s trade name and advertising (Mendelsohn, 2004). The Australian franchising sector has achieved consistent growth since the 1980s, with franchising activity currently contributing approximately (12 percent) of the country’s gross domestic product (Frazer et al., 2008). However, research has revealed that franchising systems may be unable to expand at the rate they desire owing to difficulties in obtaining franchisee finance and a shortage of suitable franchisee applicants (Price Waterhouse Coopers, 2009; Frazer et al., 2008). There are currently 56,200 business format franchised units operating in Australia (Frazer et al., 2008), accounting for approximately (5 percent) of all small business in Australia (ABS, 2009). Though this appears to suggest that franchising has the potential to expand, prior research has shown that the lack of available suitable franchisee candidates may constrain system growth and sector expansion (Frazer et al., 2008). Previous research shows that this is not a recent phenomenon (Knight, 1986; McGuire, 1971) and may be reliant upon how franchisors classify attributes that are desirable in potential incumbent franchisees (Frazer and McCosker, 1999; Hedricks and Kiefer, 2005; Michael, 2003). However, there appears to be a gap in our current understanding of how these impediments to franchise growth may be overcome. In addition to acquiring valuable insights into current recruitment practice, the primary purpose of this research is to sustain informed decision-making in the future through a study of the fundamental and under-researched question of, Thesis (PhD Doctorate), Doctor of Philosophy (PhD), Department of Marketing, Griffith Business School, Full Text

The gopher tortoise (Gopherus polyphemus) occurs in the southeastern Coastal Plain and has experienced widespread decline due to habitat loss and other human impacts. The largest remaining populations occur on private lands and military installations. Proper management at these sites will be critical to the success of the species. The goal of this study was to determine the response of gopher tortoises to forestry management practices commonly implemented in the management of the redcockaded woodpecker. We monitored habitat use of individual tortoises at four study sites with different ownership and management scenarios: Fort Gordon (military installation, winter burning), Savannah River Site (federal defense facility, winter burning, translocated population), Tillman Sand Ridge (state wildlife preserve, summer burning), and a private hunting preserve (no management). Habitat data were collected to characterize typical canopy and herbaceous vegetation of each site. Data were collected at active burrows; the anecdotal belief that tortoises select the most open habitat available was confirmed. The preferred habitat density appears to be in the range of 40 percent canopy cover, a value compatible with current woodpecker management guidelines. Results will be used to develop recommendations for the concurrent management of gopher tortoises and red-cockaded woodpeckers., Prepared in collaboration with University of Georgia's Savannah River Ecology Laboratory, Aiken, SC. The original document contains color images.

An assessment has been made of the association of 239+240Pu, 241Am and 210Po (in secular equilibrium with 210Pb) with iron minerals using a magnetic extraction technique. Grab samples of beach sand from the Cumbrian (UK) coastline were subjected to successive extractions with a ˜0.1 T ferrite magnet and a ˜0.3 T rare-earth magnet procedure to separate magnetic iron oxide minerals. Radionuclide concentrations in the magnetic extracts were enhanced (by ˜4–6-fold) relative to the residue. Those in the ˜0.1 T magnet extracts were broadly similar to those in the antiferromagnetic material extracted by the ˜0.3 T magnet, despite the very large differences in magnetic property values between the two fractions (one to two orders of magnitude). The percentage of magnetic material in terms of mass was small and therefore, the majority of these radionuclides (on average 88%) were associated with the residue. Removal of stable Fe was incomplete. Given that the radionuclides may also bind to paramagnetic (nonmagnetic) Fe minerals, the data were extrapolated by normalising the results to quantitative Fe removal. This yielded average values of 37%, 45% and 46% for 239+240Pu, 241Am and 210Po(210Pb), respectively, as upper limits for the fraction associated with magnetic+nonmagnetic Fe minerals. There are significant uncertainties inherent in quantifying data from this extraction technique. Nevertheless, it seems reasonable to conclude that radionuclide association with Fe minerals is unlikely to have a significant impact upon the physical dispersion of sediment contaminated by Sellafield discharges in the Irish Sea. However, it may be an important factor in governing Pu redox and redissolution behaviour.

The status and preliminary performance of a high capacity, three- stage, high pressure sampling system--Nuclide HT-12-90 mass spectrometer detector and data acquisition system (including time-of-flight velocity analysis of beam neutrals) is presented. A troublesome feature of the present ion source is that some modulation of background peaks occur in the presence of modulated beams. A series of attempts to heat graphite in vacuum to temperatures greater than 3000K are described. Best results are obtained with slotted pyrolytic graphite cells but arcing still limits heating to 3000 to 3100K. Carbon species through C7 have been observed from a pyrolytic graphite Knudsen cell. The C1 to C5 data agree well with literature values, at the two temperatures of 2800K and 2630K. A correlation of dimer formation versus expansion conditions for a number of gases, studied to date, indicates that nucleation cannot be ruled out in high-pressure Knudsen cells or laser heatings.

With the 2004 European Parliament elections approaching, it is useful to consider what affects voting in these elections. This paper addresses the puzzle of declining turnout in European Parliament elections. After reviewing the influential “second order elections” explanation emphasizing domestic influences on turnout, especially Mark Franklin’s recent study stressing the importance of electoral salience factors, we develop a revised model to incorporate EU as well as domestic variables. Our model indicates that EU influences, at least on the aggregate level, may have more influence on EP elections than previously reported. Tests of our model for the first five EP elections, 1979 through 1999, find that it provides an alternative explanation of turnout similar in power to Franklin’s model. Because of changes in membership of the EU, our alternative model may be preferable for explaining future turnout variation in EU elections.