Previous Exercises Research Articles

Cross-platform analysis of global microRNA expression technologies

BackgroundAlthough analysis of microRNAs (miRNAs) by DNA microarrays is gaining in popularity, these new technologies have not been adequately validated. We examined within and between platform reproducibility of four miRNA array technologies alongside TaqMan PCR arrays.ResultsTwo distinct pools of reference materials were selected in order to maximize differences in miRNA content. Filtering for miRNA that yielded signal above background revealed 54 miRNA probes (matched by sequence) across all platforms. Using this probeset as well as all probes that were present on an individual platform, within-platform analyses revealed Spearman correlations of >0.9 for most platforms. Comparing between platforms, rank analysis of the log ratios of the two reference pools also revealed high correlation (range 0.663-0.949). Spearman rank correlation and concordance correlation coefficients for miRNA arrays against TaqMan qRT-PCR arrays were similar for all of the technologies. Platform performances were similar to those of previous cross-platform exercises on mRNA and miRNA microarray technologies.ConclusionsThese data indicate that miRNA microarray platforms generated highly reproducible data and can be recommended for the study of changes in miRNA expression.

MANAGING EXCHANGE RATE VOLATILITY: A COMPARATIVE COUNTERFACTUAL ANALYSIS OF SINGAPORE, 1994–2003

This paper looks at how Singapore's exchange rate regime has coped with exchange rate volatility, by comparing the performance of Singapore's actual regime in minimizing the volatility of the nominal effective exchange rate (NEER) and the bilateral rate against the US dollar with some counterfactual regimes and the corresponding performance of eight other East Asian countries. In contrast to previous counterfactual exercises, we apply a more disaggregated methodology for the trade weights, a larger number of trade partners and ARCH/GARCH techniques to capture the time-varying characteristics of volatility. Our findings confirm that Singapore's managed floating exchange rate system has delivered relatively low currency volatility. Although there are gains in volatility reduction for all countries in the sample from the adoption of either a unilateral or a common basket peg, particularly post-Asian crisis, these gains are relatively low for Singapore, largely because of low actual volatility. There are additional gains for non-dollar peggers from stabilizing intra-east Asian exchange rates against the dollar if they were to adopt a basket peg, especially post-crisis, but the gains for Singapore are again relatively modest. Finally, the conclusion from previous counterfactual studies that there is little difference between a unilateral basket peg and a common basket peg in terms of stability reduction is confirmed.

Positive Serologic Test Results for Burkholderia pseudomallei in Asymptomatic Persons

1We caution against the use of a poorly validated serologic test to provide evidence of melioidosis in asymptomatic persons. The authors use the indirect fluorescent antibody (IFA) assay, which has not been used in disease-endemic countries for many years, and no validation of this assay is presented. Although we may assume that the test is broadly similar to the previous descriptions of the IFA assay, 2 the bacterial strains used (or if purified antigen was used, the nature of the antigen) are not defined. The authors cite earlier work by Ashdown and others who described a high specificity of the IFA assay, but in this report, only 11 of 89 patients had culture-confirmed melioidosis, with the remaining 78 diagnosed with subclinical melioidosis on the basis of serologic test results. 3 The clinical significance of asymptomatic persons with positive serologic results is unclear; whether such people have truly been infected and harbor latent infection is not known. Nevertheless, as the authors note, it is apparent that overt melioidosis does not develop in most of such patients. Furthermore, there may have been confounding by exposure to the antigenically similar but less virulent B. thailandensis that is present in Thailand but not in Australia. The higher prevalence of positive indirect hemagglutination (IHA) test results using B. pseudomallei antigen in Thai patients compared with those from northern Australia, with a broadly similar incidence of disease, may suggest that exposure to B. thailandensis may result in detectable antibodies against B. pseudomallei . 4,5 Studies of cross-reactivity between the IHA using B. thailandensis as the antigen in patients with cultureconfirmed melioidosis have not been consistent. 6,7 We suggest that the quantification of risk in groups exposed to mud and pooled surface water should be based on surveillance of culture-confirmed melioidosis in the population at risk. The authors do not offer any data on the incidence of melioidosis in occupationally exposed groups in the same area, such as during previous military exercises or in rice farmers. Approximately 20 cases of melioidosis per year are reported at the Chonburi Hospital approximately 80 km from the study site (with an unknown denominator), and a low rate of melioidosis has been documented in a hospital survey in the central region of Thailand compared with the northeast Issan region. 8,9 In summary, the clinical significance of seropositive asymptomatic persons in this study is doubtful, given the use of a poorly characterized serologic test, possible confounding by exposure to B. thailandensis , the lack of a non-exposed control group, and the lack of a clinical picture characteristic of melioidosis in all but one of these patients.

Anatomy of and Lessons Learned from a Canadian National-Scale Radiological Exercise: ExIT-08

Exercise Initial Thunder (ExIT-08) was the fourth in a series of four emergency response exercises sponsored by the Chemical, Biological, Radiological, Nuclear and Explosives Research and Technology Initiative (CRTI). It was designed to test the Canadian Federal, Provincial and Municipal response to a terrorist attack using radioactive materials. The complexity of this exercise had been increased over previous exercises to now include provincial and municipal players. As a result about 350 persons participated as players in the 4-day exercise that was held in two locations in the western part of Canada. This paper summarizes the experiences and the lessons learned of the Health Canada (HC) team.

Tourism Studies and the Governance of Higher Education in the United Kingdom

A major academic debating point in recent times has been the impact of the Research Assessment Exercise (RAE) on the higher education sector in the UK. Ex-post analyses of the RAE's effects have appeared but this paper argues for a more forward-looking perspective. RAE 2008 is different to previous exercises, set as it is amid a period of significant reform and turbulence in the sector. Rather than exclusively dwelling on the past, it is necessary to explore how tourism studies and tourism geography will fare in the new era. While there has been transparency in the dissemination of change and much is known about what is to come, several important ‘unknowns’ remain, not least how several reforms will function together. An attempt is made to identify likely changes and to map their potential impacts on the future nature and practice of tourism scholarship.

Development and Implementation of a Functional Exercise to Assess Public Health Agency Response to Foodborne Bioterrorism

Agroterrorism and food terrorism have been identified as important homeland security issues by officials in the public health, government, and food industry sectors of the U.S. Intentional contamination of food has already occurred both abroad and in North America. Outbreak investigation and control measures in response to intentional contamination differ from those employed in cases of naturally occurring contamination. Operations-based exercise efforts specific to bioterrorism events are essential to train public health personnel and first responders to consider the possibility of deliberate contamination during an outbreak investigation. A recent search of the Rand Corporation's Public Health Preparedness database identified no operations-based (functional or full-scale) exercises involving foodborne contamination with a biological or chemical agent.This manuscript describes a functional exercise developed and conducted by the University of Illinois, College of Veterinary Medicine, Section of Community Health and Preventive Medicine. The functional exercise simulated a food-borne terrorism event and was designed to evaluate the efficacy of the Food Emergency Response Plan (FERP) of the Illinois Department of Public Health (IDPH), Division of Food, Drugs and Dairies (DFDD). The exercise was held on November 18th and 19th, 2008 at the College of Veterinary Medicine, University of Illinois, Urbana, IL.Based on this and previous exercises and training programs developed and conducted by CHPM, it is apparent that the more exercise designers, evaluators and public health and support agency participants move away from discussion based exercises and towards operations based exercises, the more strengths and deficiencies in preparation and response of participating agencies are revealed. Although public health agencies have begun training personnel and partner agencies to consider intentional contamination of food during an outbreak investigation, the relative lack of widespread operations-based exercises to assess preparedness in response to an intentional incident of food-borne contamination seems to be an important deficiency in homeland security. Additional funding to create opportunities for public health and first responder personnel to participate in operations-based bioterrorism response exercises is needed.

A Comparison of Forecast Performance Between Federal Reserve Staff Forecasts, Simple Reduced-Form Models, and a DSGE Model

This paper considers the 'real-time' forecast performance of the Federal Reserve staff, time-series models, and an estimated dynamic stochastic general equilibrium (DSGE) model--the Federal Reserve Board's new Estimated, Dynamic, Optimization-based (Edo) model. We evaluate forecast performance using out-of-sample predictions from 1996 through 2005, thereby examining over 70 forecasts presented to the Federal Open Market Committee (FOMC). Our analysis builds on previous real-time forecasting exercises along two dimensions. First, we consider time-series models, a structural DSGE model that has been employed to answer policy questions quite different from forecasting, and the forecasts produced by the staff at the Federal Reserve Board. In addition, we examine forecasting performance of our DSGE model at a relatively detailed level by separately considering the forecasts for various components of consumer expenditures and private investment. The results provide significant support to the notion that richly specified DSGE models belong in the forecasting toolbox of a central bank.

Monetary Policy and Potential Output Uncertainty: A Quantitative Assessment

I estimate a dynamic stochastic general equilibrium model where the policymaker and the private sector have imperfect knowledge about potential output. The estimation of the structural parameters and of the monetary authorities’objectives is key to assess the quantitative relevance of the imperfect information problem and to evaluate the robustness of previous exercises based on calibration. The estimated model also allows me to revisit the Orphanides (2001, 2003) findings that the central bank can makes large and persistent mistakes to estimate potential output in response to productivity and cost shocks. I find that when real unit labor cost is used as a monetary policy indicator, the potential output uncertainty has quantitatively negligible consequences on policy behaviour and inflation dynamics. JEL Classification: E4, E5

A guided swat model application on sediment yield modeling in Pangani river basin: lessons learnt

The overall objective of this paper is to report on the lessons learnt from applying Soil and Water Assessment Tool (SWAT) in a well guided sediment yield modelling study. The study area is the upstream of Pangani River Basin (PRB), the Nyumba Ya Mungu (NYM) reservoir catchment, located in the North Eastern part of Tanzania. It should be noted that, previous modeling exercises in the region applied SWAT with pre- assumption that inter-rill or sheet erosion was the dominant erosion type. In contrast, in this study SWAT model application was guided by results of analysis of high temporal resolution of sediment flow data and hydro-meteorological data. The runoff component of the SWAT model was calibrated from six-years (i.e. 1977-1982) of historical daily streamflow data. The sediment component of the model was calibrated using one-year (1977-1988) daily sediment loads estimated from one hydrological year sampling programme (between March and November, 2005) rating curve. A long-term period over 37 years (i.e. 1969-2005) simulation results of the SWAT model was validated to downstream NYM reservoir sediment accumulation information. The SWAT model captured 56 percent of the variance (CE) and underestimated the observed daily sediment loads by 0.9 percent according to Total Mass Control (TMC) performance indices during a normal wet hydrological year, i.e., between November 1, 1977 and October 31, 1978, as the calibration period. SWAT model predicted satisfactorily the long-term sediment catchment yield with a relative error of 2.6 percent. Also, the model has identified erosion sources spatially and has replicated some erosion processes as determined in other studies and field observations in the PRB. This result suggests that for catchments where sheet erosion is dominant SWAT model may substitute the sediment-rating curve. However, the SWAT model could not capture the dynamics of sediment load delivery in some seasons to the catchment outlet.

Evaluation of an interlaboratory proficiency-testing exercise for total mercury in environmental samples of soils, sediments and fish tissue

A proficiency-testing scheme concerning total mercury determination in soils and sediments (with different levels of contamination) and fish tissue involved 25 European laboratories as participants, who used their regular in-house analytical methods, and reference values were determined from the results obtained. The most precise results were obtained for the fish matrix. The majority of participants obtained satisfactory Z-scores, and laboratories that need to revise their procedures were singled out. When compared with performances in other previous interlaboratory exercises for total mercury, the overall performance of participants may be considered satisfactory, and the ability to produce results of acceptable quality for mercury appears to be improving.

Creating "Kantri" in Central New Guinea: Relational Ontology and the Categorical Logic of Statecraft

Creating "Kantri" in Central New Guinea: Relational Ontology and the Categorical Logic of Statecraft

Geochemistry and mineralogy of arsenic in (natural) anaerobic groundwaters

Here new data from field bioremediation experiments and geochemical modeling are reported to illustrate the principal geochemical behavior of As in anaerobic groundwaters. In the field bioremediation experiments, groundwater in Holocene alluvial aquifers in Bangladesh was amended with labile water-soluble organic C (molasses) and MgSO 4 to stimulate metabolism of indigenous SO 4 -reducing bacteria (SRB). In the USA, the groundwater was contaminated by Zn, Cd and SO 4 , and contained <10 μg/L As under oxidized conditions, and a mixture of sucrose and methanol were injected to stimulate SRB metabolism. In Bangladesh, groundwater was under moderately reducing conditions and contained ∼10 mg/L Fe and ∼100 μg/L As. In the USA experiment, groundwater rapidly became anaerobic, and dissolved Fe and As increased dramatically (As > 1000 μg/L) under geochemical conditions consistent with bacterial Fe-reducing conditions. With time, groundwater became more reducing and biogenic SO 4 reduction began, and Cd and Zn were virtually completely removed due to precipitation of sphalerite (ZnS) and other metal sulfide mineral(s). Following precipitation of chalcophile elements Zn and Cd, the concentrations of Fe and As both began to decrease in groundwater, presumably due to formation of As-bearing FeS/FeS 2 . By the end of the six-month experiment, dissolved As had returned to below background levels. In the initial Bangladesh experiment, As decreased to virtually zero once biogenic SO 4 reduction commenced but increased to pre-experiment level once SO 4 reduction ended. In the ongoing experiment, both SO 4 and Fe(II) were amended to groundwater to evaluate if FeS/FeS 2 formation causes longer-lived As removal. Because As-bearing pyrite is the common product of SRB metabolism in Holocene alluvial aquifers in both the USA and Southeast Asia, it was endeavored to derive thermodynamic data for arsenian pyrite to better predict geochemical processes in naturally reducing groundwaters. Including the new data for arsenian pyrite into Geochemist’s Workbench, its stability field completely dominates in reducing Eh–pH space and “displaces” other As-sulfides (orpiment, realgar) that have been implied to be important in previous modeling exercises and reported in rare field conditions. In summary, when anaerobic bacterial metabolism is optimized by providing both electron donors and acceptors, As is mobile under Fe-reducing conditions, immobile under SO 4 -reducing conditions, and arsenian pyrite is the likely stable mineral phase formed under SO 4 -reducing conditions, instead of pure As–S phases such as realgar or orpiment.

League Tables, Love Them or Hate Them

Medicine does not entirely ignore qualitative research but is, understandably, happier with objective measurements and with numbers to which well-established techniques of summary statistics and more sophisticated analysis can be applied. Lately, several countries, including the UK, have been trying to devise numerical performance indicators for services such as health and education, the idea being to find the equivalent of the balance sheet in the commercial sector so that hospitals and schools can be run more like businesses. The results are published, often as league tables. Forum for the Future, a UK-based charity, has recently carried out a similar ranking exercise for British cities.1 All over the urban world there is competition to be (or be perceived to be) “green,” however that is defined, and the UK is no exception. One city aims to be the greenest in Britain by 2010, another wishes to be seen as “the green capital,” while yet another has the bold ambition to be “the most sustainable city in the world.” Forum for the Future is seeking to provide some objectivity to back up aspirations like these and so “create healthy competition between cities to encourage sustainable urbanization” in a country where 90% of the population now lives in a town or city. The ranking will be an annual one so cities will move up and down just as schools and hospitals do in their yearly league tables. The urban exercise has its weaknesses, the most obvious perhaps being that there appears to be no adjustment for socioeconomic class structure. Brighton and Hove, which comes out on top in the overall ranking (and for two of the three data subsets), is a coastal city in the south–east and can fairly, if not uniformly, be described as affluent. Liverpool, in the north–west and with a port and industrial heritage, was bottom and pockets of affluence are harder to find. Indeed, the report itself concedes that “affluence helps.” The top score was 166.9 points and the bottom 76.7. The report uses 13 criteria in 3 packages called environmental impact, quality of life, and future proofing, and the criteria selected are ones where assessments are available from sources such as the UK's Environment Agency. Six examples of the criteria, two from each package, are: air quality (which can affect quality of life) and waste collected per head of population, healthy life expectancy at age 65 and attained educational level, and local authority commitment to action on climate change and the number of “green” businesses in its area. Local people, local authority staff, elected councilors, and research scientists could give different weightings to the criteria and may be tempted to play around with the figures to get different outcomes. Also, some criteria are fairly reliable measurements whereas others are a bit woollier. Forum for the Future says that there is a “long way to go” and it is critical of previous exercises in urban renaissance, labeling them “iconic trophy-collecting.” In other words, winning an architectural prize for some inner-city shopping mall and recreational development does not make a more sustainable city. So, Liverpool can take some consolation from its winning of the Forum's wooden spoon. In 2008, this city is the European City of Culture.

THE CHOICE OF EXCHANGE RATE REGIME AND THE VOLATILITY OF EXCHANGE RATES BEFORE AND AFTER THE ASIAN CRISIS: A COUNTERFACTUAL ANALYSIS

This paper carries out a counterfactual analysis of the impact of alternative exchange rate regimes on the volatility of the nominal effective exchange rate (NEER) and the bilateral rate against the US dollar for nine East Asian countries, both before and after the Asian financial crisis. Our hypothetical regimes include a unilateral basket peg (UBP), a common basket peg (CBP) and a hard peg against the $US, but in contrast to previous counterfactual exercises which compute the weights for effective exchange rates on the basis of simple bloc aggregates, we apply a more disaggregated methodology using a larger number of trade partners and utilise ARCH/GARCH techniques to better capture the time-varying characteristics of volatility. Our results suggest that a UBP would minimise effective exchange rate volatility for all countries both before and after the crisis and provides the highest regime gains compared to actual. Although the gains for a CBP are always less than those for a UBP the absolute differences between the two regimes appear to be small. In terms of bilateral exchange rates against the dollar the gains from a UBP or CBP could also be quite significant for the non-dollar peggers, especially post-crisis, since a fall in effective instability would be accompanied by a fall in bilateral instability.

Participative backcasting: A tool for involving stakeholders in local sustainability planning

This paper reports on the use of a backcasting approach with local stakeholders in five European cities where several Images of the Future were formulated for household consumption in sustainable cities. The aim was to find methods for inspiring local stakeholders to participate in discussions about sustainability with a long-term perspective. Previous exercises of similar kinds have mainly involved experts. A method based on workshops and back-office work was developed and is described and analysed here, together with the results obtained. The outcomes in terms of ideas, votes and dimensions are also discussed. The findings suggest that the method worked reasonably well, with the process quality receiving the highest ratings. The quality of outcomes was perceived as less reliable. Adaptations should include more efforts to recruit participants with varied backgrounds and more innovative approaches for liberating subjects’ minds during the time travel stage of the process. The outcomes obtained show that there appears to be a common set of popular ideas for more sustainable everyday city life in the EU, including more local and organic food, a greener environment, better public transport and opportunities for non-motorised transport and reorientation of values.

Exercise Maritime Response (EXMR): Lessons Learned for Population Monitoring and Communications

Exercise Maritime Response was the third in a series of four emergency response exercises sponsored by the Chemical, Biological, Radiological and Nuclear Research and Technology Initiative. It was designed to test the Canadian Federal, Provincial and Municipal response to a terrorist attack using radioactive materials. The complexity of this exercise had been increased over previous exercises to now include simulated contaminated members of the public. This paper summarizes the experiences, and the lessons learned, of the Health Canada (HC) team. The largest issues identified by the HC team were: crowd control, insufficiency of staff to deal with surge capacity, and communications. The exercise did prove that the population monitoring equipment worked well and that small amounts of radioactivity were easily identified and quantified to within 20% of their true value.

Comparison of box-air-mass-factors and radiances for Multiple-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) geometries calculated from different UV/visible radiative transfer models

Abstract. The results of a comparison exercise of radiative transfer models (RTM) of various international research groups for Multiple AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) viewing geometry are presented. Besides the assessment of the agreement between the different models, a second focus of the comparison was the systematic investigation of the sensitivity of the MAX-DOAS technique under various viewing geometries and aerosol conditions. In contrast to previous comparison exercises, box-air-mass-factors (box-AMFs) for different atmospheric height layers were modelled, which describe the sensitivity of the measurements as a function of altitude. In addition, radiances were calculated allowing the identification of potential errors, which might be overlooked if only AMFs are compared. Accurate modelling of radiances is also a prerequisite for the correct interpretation of satellite observations, for which the received radiance can strongly vary across the large ground pixels, and might be also important for the retrieval of aerosol properties as a future application of MAX-DOAS. The comparison exercises included different wavelengths and atmospheric scenarios (with and without aerosols). The strong and systematic influence of aerosol scattering indicates that from MAX-DOAS observations also information on atmospheric aerosols can be retrieved. During the various iterations of the exercises, the results from all models showed a substantial convergence, and the final data sets agreed for most cases within about 5%. Larger deviations were found for cases with low atmospheric optical depth, for which the photon path lengths along the line of sight of the instrument can become very large. The differences occurred between models including full spherical geometry and those using only plane parallel approximation indicating that the correct treatment of the Earth's sphericity becomes indispensable. The modelled box-AMFs constitute an universal data base for the calculation of arbitrary (total) AMFs by simple convolution with a given trace gas concentration profile. Together with the modelled radiances and the specified settings for the various exercises, they can serve as test cases for future RTM developments.

Monetary Policy and Potential Output Uncertainty: A Quantitative Assessment

This paper contributes to the recent literature that studies the quantitative implications of the imperfect information about potential output for the conduct of monetary policy. By means of Bayesian techniques, a small New Keynesian model is estimated taking explicitly account of the imperfect information problem. The estimation of the structural parameters and of the monetary authorities' objectives is key in assessing the quantitative relevance of the imperfect information problem and in evaluating the robustness of previous exercises based on calibration. Finally, the model allows us to analyse the usefulness of unit labor costs as monetary policy indicator.

Mass Medication Modeling in Response to Public Health Emergencies

This article presents the outcomes of a full-scale training exercise utilizing a drive-thru clinic model for dispensing of Strategic National Stockpile medication. The Hawaii Department of Health developed a clinic design for vehicles based on previous exercises and research on sample throughput rates. The streamlined model selected includes a triage area near the entrance and consecutive stations for the public to register, have an evaluation for drug contradictions, and receive the medication. During the 2-hour exercise held in April 2005, a total of 622 patients were processed in their vehicles for an overall rate of 5.2 persons per minute. Although patient services were reduced in comparison to current walk-in clinic models, the public was able to receive prophylactic medication in a timely manner with a high rate of accuracy and minimal human-to-human contact. These results demonstrate that local health departments, particularly in rural areas, can provide essential medications, vaccinations, or rations through a drive-thru clinic, thus limiting morbidity and mortality during a public health emergency.

Optimal Exercise Patterns and Valuation of Employee Stock Options: An Approximate Dynamic Programming Approach

This paper develops a procedure for modeling the optimal exercise patterns and for determining the value of employee stock options. I develop an approximate dynamic programming (ADP) procedure and show how ADP can be used instead of traditional backward dynamic programming to solve the single stock option problem. I show how ADP can be extended to solve a high dimensional problem numerically that allows for a portfolio of heterogeneous options while using a CRRA utility function. I then demonstrate that the exercise of an option depends importantly on the payouts of the previous exercises.