Geothermal systems in the Chalk of the south east of England: methods of predicting thermal transport in a fractured aquifer

There has recently been a steady increase in the number of licenses granted for the abstraction of water from the Chalk aquifer beneath London to supply "open loop" geothermal systems (Environment Agency, 2007). However, there has been little research conducted on how the water re-injected by these systems, which often differs in temperature by as much as 10°C, will interact with the fractured Chalk aquifer in both the short and long term. An analytical solution developed by Bodvarsson (1989) was used to show that, for most configurations of a geothermal system, thermal transport would be governed by fractures. It was then proved that the United States Geological Survey SUTRA code could be used to construct a more detailed model of the aquifer. A thermal test was devised to collect hydrogeological and thermal data. This test, along with conventional site investigation techniques, was used at a site in central London. A detailed numerical model of the geothermal system and the aquifer was then constructed in SUTRA. The results showed that the fracture zones found during testing would affect the system performance. Building on these results a procedure was developed for designers, to ensure such systems function in an appropriate way

Climatic versus biotic constraints on carbon and water fluxes in seasonally drought-affected ponderosa pine ecosystems

We investigated the relative importance of climatic versus biotic controls on gross primary production (GPP) and water vapor fluxes in seasonally drought-affected ponderosa pine forests. The study was conducted in young (YS), mature (MS), and old stands (OS) over 4 years at the AmeriFlux Metolius sites. Model simulations showed that interannual variation of GPP did not follow the same trends as precipitation, and effects of climatic variation were smallest at the OS (50%), and intermediate at the YS (<20%). In the young, developing stand, interannual variation in leaf area has larger effects on fluxes than climate, although leaf area is a function of climate in that climate can interact with age-related shifts in carbon allocation and affect whole-tree hydraulic conductance. Older forests, with well-established root systems, appear to be better buffered from effects of seasonal drought and interannual climatic variation. Interannual variation of net ecosystem exchange (NEE) was also lowest at the OS, where NEE is controlled more by interannual variation of ecosystem respiration, 70% of which is from soil, than by the variation of GPP, whereas variation in GPP is the primary reason for interannual changes in NEE at the YS and MS. Across spatially heterogeneous landscapes with high frequency of younger stands resulting from natural and anthropogenic disturbances, interannual climatic variation and change in leaf area are likely to result in large interannual variation in GPP and NEE

Tidal Disruption Event Host Galaxies in the Context of the Local Galaxy Population

We study the properties of tidal disruption event (TDE) host galaxies in the context of a catalog of ~500,000 galaxies from the Sloan Digital Sky Survey. We explore whether selection effects can account for the overrepresentation of TDEs in E+A/post-starburst galaxies by creating matched galaxy samples. Accounting for possible selection effects due to black hole (BH) mass, redshift completeness, strong AGN presence, bulge colors, and surface brightness can reduce the apparent overrepresentation of TDEs in E+A host galaxies by a factor of ~4 (from ~$\times$100-190 to ~$\times$25-48), but cannot fully explain the preference. We find that TDE host galaxies have atypical photometric properties compared to similar, "typical" galaxies. In particular, TDE host galaxies tend to live in or near the "green valley" between star-forming and passive galaxies, and have bluer bulge colors ($\Delta (g-r) \approx 0.3$ mag), lower half-light surface brightnesses (by ~1 mag/arcsec$^2$), higher Sersic indices ($\Delta n_{\rm g} \approx 3$), and higher bulge-to-total-light ratios ($\Delta B/T \approx 0.5$) than galaxies with matched BH masses. We find that TDE host galaxies appear more centrally concentrated and that all have high galaxy Sersic indices and $B/T$ fractions---on average in the top 10% of galaxies of the same BH mass---suggesting a higher nuclear stellar density. We identify a region in Sersic index and BH mass parameter space that contains ~2% of our reference catalog galaxies but $\ge\!60\%$ of TDE host galaxies. The unique photometric properties of TDE host galaxies may be useful for selecting candidate TDEs for spectroscopic follow-up observations in large transient surveys.Comment: 26 pages, 11 figures, 5 tables. Published in Ap

Young GI angle: Choosing a mentor/mentee

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/166219/1/ueg2bf01002.pd

L’intégration des évaluations de l’apprentissage autorégulé dans les activités d’évaluation dans les professions de la santé : un appel à l’action

How well have healthcare professionals and trainees been prepared for the inevitable demands for new learning that will arise in their future? Given the rapidity with which ‘core healthcare knowledge’ changes, medical educators have a responsibility to audit whether trainees have developed the capacity to effectively self-regulate their learning. Trainees who engage in effective self-regulated learning (SRL) skilfully monitor and control their cognition, motivation, behaviour, and environment to adaptively meet demands for new learning. However, medical curricula rarely assess trainees’ capacity to engage in this strategic process. In this position paper, we argue for a paradigm shift toward assessing SRL more deliberately in undergraduate and postgraduate programs, as well as in associated licensing activities. Specifically, we explore evidence supporting an innovative blend of principles from the science on SRL, and on preparation for future learning (PFL) assessments. We propose recommendations for how program designers, curriculum developers, and assessment leads in undergraduate and postgraduate training programs, and in licensing bodies can work together to develop integrated assessments that measure how and how well trainees engage in SRL. Claims about lifelong learning in health professions education have gone unmatched by responsive curricular changes for far too long. Further neglecting these important competencies represents a disservice to medical trainees and a potential risk to the future patients they will care for.Dans quelle mesure les professionnels de la santé et les étudiants ont-ils été préparés aux exigences inévitables de nouveaux apprentissages qui se présenteront à eux à l’avenir? Étant donné la rapidité avec laquelle les « connaissances de base en matière de soins de santé » évoluent, les enseignants en médecine ont la responsabilité de vérifier si les étudiants ont développé la capacité d’autoréguler adéquatement leurs apprentissages. Ceux qui pratiquent efficacement l’apprentissage autorégulé (AAR) surveillent et contrôlent habilement leur cognition, leur motivation, leur comportement et leur environnement pour s’adapter à la nécessité de nouveaux apprentissages. Cependant, les programmes d’études médicales évaluent rarement la capacité des étudiants à s’engager dans ce processus stratégique. Dans cet exposé de position, nous plaidons en faveur d’un changement de paradigme vers une évaluation plus ciblée de l’AAR dans les formations doctorale et postdoctorale, ainsi que pour les activités d’évaluation. Plus précisément, nous explorons les résultats convaincants de l’emploi d’un mélange innovant de principes issus de la recherche en matière d’AAR et d’évaluations de la préparation à l’apprentissage futur. Nous proposons des recommandations pour une collaboration entre les responsables de la conception de programmes d’études, ceux de l’élaboration du cursus, ceux chargés de l’évaluation dans les programmes d’études prédoctorales et postdoctorales et les organismes responsables de l’octroi d’un titre de compétence en vue de créer des évaluations intégrées qui mesurent la méthode et la qualité de l’AAR chez les étudiants. Les programmes d’études tardent encore à traduire dans la pratique la reconnaissance de l’importance de l’apprentissage tout au long de la vie dans l’éducation médicale. Continuer à négliger ces compétences importantes ne ferait que nuire aux étudiants en médecine et potentiellement à leurs futurs patients

Consumer-Centric Protection for Online Social Networks

Online Social Networks (OSNs) are a unique construct that is shaped by the advancement and availability of Internet technologies. A large portion of internet users make use of OSN services to share and celebrate their personal lives with friends and family. A substantial proportion of these shared experiences revolve around privacy-sensitive information. The OSN services handling privacy-sensitive information deploy state-of-the-art security and privacy preserving mechanisms. However, these protections are, to a great extent, not consumer-centric: this is the main focus of this study. In this paper, we define the notion of Consumer-Centric Protection (CCP) for OSNs. In this proposal, the individual user controls how her data can be accessed by her contacts (e.g. friends and family members) and others, thus giving control of user data back to the rightful owner — the user. This work is still in progress and in this paper we present our preliminary result

Waste heat recovery from industrial baking ovens

Under this work, a system level energy model of an industrial-scale baking oven with an integrated waste heat recovery unit is developed using experimentally determined inputs to estimate the potential benefits of a gas-to-gas heat recovery system. This work has demonstrated that at least 4% savings in the oven fuel consumption can be achieved, reducing the annual running costs by £4,207. An environmental assessment indicates reduction of circa 43 tonnes in CO2 emissions per annum. The study also provides a systematic methodology to test low temperature gas-to-gas heat recovery technology for food manufacturing process

A Bayesian analysis of classical shadows

The method of classical shadows heralds unprecedented opportunities for quantum estimation with limited measurements [H.-Y. Huang, R. Kueng, and J. Preskill, Nat. Phys. 16, 1050 (2020)]. Yet its relationship to established quantum tomographic approaches, particularly those based on likelihood models, remains unclear. In this article, we investigate classical shadows through the lens of Bayesian mean estimation (BME). In direct tests on numerical data, BME is found to attain significantly lower error on average, but classical shadows prove remarkably more accurate in specific situations -- such as high-fidelity ground truth states -- which are improbable in a fully uniform Hilbert space. We then introduce an observable-oriented pseudo-likelihood that successfully emulates the dimension-independence and state-specific optimality of classical shadows, but within a Bayesian framework that ensures only physical states. Our research reveals how classical shadows effect important departures from conventional thinking in quantum state estimation, as well as the utility of Bayesian methods for uncovering and formalizing statistical assumptions.Comment: 8 pages, 5 figure

Estimation and uncertainty quantification for the output from quantum simulators

The problem of estimating certain distributions over $\{0,1\}^d$ is considered here. The distribution represents a quantum system of $d$ qubits, where there are non-trivial dependencies between the qubits. A maximum entropy approach is adopted to reconstruct the distribution from exact moments or observed empirical moments. The Robbins Monro algorithm is used to solve the intractable maximum entropy problem, by constructing an unbiased estimator of the un-normalized target with a sequential Monte Carlo sampler at each iteration. In the case of empirical moments, this coincides with a maximum likelihood estimator. A Bayesian formulation is also considered in order to quantify posterior uncertainty. Several approaches are proposed in order to tackle this challenging problem, based on recently developed methodologies. In particular, unbiased estimators of the gradient of the log posterior are constructed and used within a provably convergent Langevin-based Markov chain Monte Carlo method. The methods are illustrated on classically simulated output from quantum simulators

A Visual Rhetorical Analysis of Selected Nexium Prescription Drug Advertisements According to the Methodology of Sonja Foss

Direct‐to‐consumer advertising has gathered much negative attention. It’s purpose is filled with questions of ethics and legitimacy. This analytical study takes a deeper look into the advertisements that promote prescription drugs. The advertisements can be seen at the flip of a magazine, click of a button, or a walk down the road. The methodology for analyzing visual images according to Sonja Foss provided a framework to provide results. This preliminary study found evident problems in the drug advertising industry. Further research was beckoned due to the findings of this exploratory project