Wage shocks and consumption variability in Mexico during the 1990s

This paper presents evidence on the relationship between shocks to relative male wages, and changes in household consumption in Mexico during the 1990s decade, which is a period characterized by high volatility. Apart from performing analysis of this type for Mexico for the first time, the paper has mainly two contributions. The first is the use of alternative data sources to construct instrumental variables for wages. The second is to examine differences across four consumption categories: non-durable goods, durable goods, education and health. Our results for non-durable goods consumption reject the hypothesis that Mexican households are able to insure idiosyncratic risk. For the comparisons across consumption categories, the conclusion is that households in Mexico tend to react to temporary shocks by contracting the consumption of goods that represents longer run investment in human capital, which makes them more vulnerable in the future

Evaluation of a locally homogeneous flow model of spray combustion

A model of spray combustion which employs a second-order turbulence model was developed. The assumption of locally homogeneous flow is made, implying infinitely fast transport rates between the phase. Measurements to test the model were completed for a gaseous n-propane flame and an air atomized n-pentane spray flame, burning in stagnant air at atmospheric pressure. Profiles of mean velocity and temperature, as well as velocity fluctuations and Reynolds stress, were measured in the flames. The predictions for the gas flame were in excellent agreement with the measurements. The predictions for the spray were qualitatively correct, but effects of finite rate interphase transport were evident, resulting in a overstimation of the rate development of the flow. Predictions of spray penetration length at high pressures, including supercritical combustion conditions, were also completed for comparison with earlier measurements. Test conditions involved a pressure atomized n-pentane spray, burning in stagnant air at pressures of 3, 5, and 9 MPa. The comparison between predictions and measurements was fair. This is not a very sensitive test of the model, however, and further high pressure experimental and theoretical results are needed before a satisfactory assessment of the locally homogeneous flow approximation can be made

Using randomized experiments and structural models for 'scaling up': evidence from the PROGRESA evaluation

The evaluation of welfare programs and more generally government or international organisms interventions is often posed as a one off question, in that evaluators ask whether a specific intervention achieves a specific objective in a specific situation. However,recently, the more general question of whether results from a given studies can be used to predict the effect of different interventions in,possibly,different contexts has received a considerable amount of attention. The usefulness of such an exercise, if successful, is obvious. The ability to extrapolate success stories and avoid failures in different situations would obviously be highly desirable. Unfortunately, a rigorous and successful extrapolation is extremely difficult. Perhaps such difficulties should not be unexpected,given the problems that often one encounters in establishing the effects of social programs in non experimental settings. In this paper we discuss at length the issues involved with the evaluation of social interventions and with the attempts at 'scaling them up'. In particular, we discuss the relative merits of non- parametric evaluation strategies that rely on (possibly experimental) exogenous variation to estimate the impact effects and of more structural approaches. The difference between the two approaches is particularly relevant when one comes to the issue of 'extrapolation' and 'scaling up'. In principle one could consider two types of extrapolation and scaling up. First, one might want to predict the effects of a program that is different from the one that was evaluated or the effect of changing some aspects of the program evaluated. Second, one might want to predict the effect of exporting an existing program from a population where its effects were evaluated (evaluation population) to a different population (implementation population). In what follow we focus on the latter problem and discuss the former only marginally. After considering extensively the conceptual and technical issues involved with this type of exercises, we apply the ideas we discuss to the results from the evaluation of PROGRESA , a large welfare program in Mexico, for which a randomized evaluation sample is available and has been extensively studied. In particular, we divide the seven Mexican states in which the evaluation was carried out in two groups and check to what extent the results in one group can be extrapolated to the other. The advantage of such a strategy is that one can compare the extrapolation results (based on a structural model) with the actual 'ex-post' evaluation that can be carried out either by simple comparison of means or by structural methods

Using randomised experiments and structural models for 'scaling up': evidence from the PROGRESA evaluation

The evaluation of welfare programs and more generally government or international organisma interventions is often posed as a one off question, in that evaluators ask whether a specific intervention achieves a specific objective in a specific situation. However, recently, the more general questions of whether results from a given study can be used to predict the the effect of different interventions in, possibly, different contexts has received a considerable amount of attention. The usefulness of such an exercise, if successful, is obvious. The ability to extrapolate success stories and avoid failures in different situation would obviously be highly desirable. Unfortunately a rigorous and successful extrapolation is extremely difficult. In this paper we discuss the issues involved with the evaluation of social interventions and with the attempts at 'scaling them up'. In particular we discuss the realtive merits of non-parametric evaluation strategies that rely on (possibly experimental) exogenous variation to estimate the impact effects and of more structural approaches. The difference between the two appraoches is particularly relevant when one comes to the issue of 'extrapolation' and 'scaling up'. One could consider two types of extrapolation: (i) Predict the effects of a program that is different from the one that was evaluated; (ii) predict the effect of exporting an existing program from a context where is was evaluated to a different one. In this paper we focus on the latter problem. After discussing the conceptual and technical issues, we apply the ideas we discuss to the results from the evluation of PROGRESA, a large welfare program in Mexico, for which a randomized evaluation sample is available and has been extensively studied. In particular, we divide the seven Mexican states in which the evaluation was carried out into two groups and check to what extent the results in one group can be extrapolated to the others

Photometry of SN 2002bo with template image subtraction

VRI photometry of the type Ia supernova 2002bo is presented. This SN exploded in a dusty region of the host galaxy NGC 3190, thus, subtraction of a template frame was necessary to obtain reliable photometry. We used a template frame of NGC 3190 taken during the course of our galaxy imaging project, fortunately, just a few days before SN 2002bo was discovered. The aim of this project is to collect template frames of nearby galaxies that are potential hosts of bright SNe. Subtraction of pre-SN images helped us to exclude the background light contamination of the host galaxy. The maximum occurred at JD 2452346, with maximal V brightness of 13.58. MLCS analysis led to T0(B)=JD 2452346.1 pm 0.8 (fiducial B-maximum), E(B-V)=0.24 pm 0.02, mu0=32.46 pm 0.06, Delta=-0.14 pm 0.04. E(B-V)=0.24(2) indicates a significant extinction in the host galaxy as the galactic reddening is negligible toward NGC 3190. The accepted value of Delta indicates that SN 2002bo was a slightly overluminous SN by about 0.14 relative to fiducial SN Type Ia. The distance turned out to be 31.0 pm 3 Mpc. In addition, the heavily obscured SN 2002cv was also detected on the I frame taken on JD 2452434 (June 8, 2002), and a variable star is found in the field, very close to the host galaxy.Comment: accepted by Astronomy and Astrophysic

Contactless Thermal Characterization Method of PCB-s Using an IR Sensor Array

In this paper the feasibility study of an IR sensor card is presented. The methodology and the results of a quasi real-time thermal characterization tool and method for the temperature mapping of circuits and boards based on sensing the infrared radiation is introduced. With the proposed method the IR radiation-distribution of boards from the close proximity of the sensor card is monitored in quasi real-time. The proposed method is enabling in situ IR measurement among operating cards of a system e.g. in a rack.Comment: Submitted on behalf of TIMA Editions (http://irevues.inist.fr/tima-editions

Integrating spatial data and shorebird nesting locations to predict the potential future impact of global warming on coastal habitats: A case study on Farasan Islands, Saudi Arabia

AbstractOne of the expected effects of the global warming is changing coastal habitats by accelerating the rate of sea level rise. Coastal habitats support large number of marine and wetland species including shorebirds (plovers, sandpipers and allies). In this study, we investigate how coastal habitats may be impacted by sea level rise in the Farasan Islands, Kingdom of Saudi Arabia. We use Kentish plover Charadrius alexandrinus – a common coastal breeding shorebird – as an ecological model species to predict the influence of sea level rise. We found that any rise of sea level is likely to inundate 11% of Kentish plover nests. In addition, 5% of the coastal areas of Farasan Islands, which support 26% of Kentish plover nests, will be flooded, if sea level rises by one metre. Our results are constrained by the availability of data on both elevation and bird populations. Therefore, we recommend follow-up studies to model the impacts of sea level rise using different elevation scenarios, and the establishment of a monitoring programme for breeding shorebirds and seabirds in Farasan Islands to assess the impact of climate change on their populations

Crisis management during anaesthesia: water intoxication

© 2005 BMJ Publishing Group Ltd.Background: Irrigation of closed body spaces may lead to substantial perioperative fluid and electrolyte shifts. A syndrome occurring during transurethral resection of prostate (TURP), and a similar syndrome described in women undergoing transcervical endometrial ablation (TCEA) are both characterised by a spectrum of symptoms which may range from asymptomatic hyponatraemia to convulsions, coma, and death. Such potentially serious consequences require prompt recognition and appropriate management of this "water intoxication" syndrome. Objectives: To examine the role of a previously described core algorithm "COVER ABCD–A SWIFT CHECK", supplemented by a specific sub-algorithm for water intoxication, in the management of this syndrome occurring in association with anaesthesia. Methods: The potential performance of this structured approach for each of the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS) was compared with the actual management as reported by the anaesthetists involved. Results: From the first 4000 incidents reported to AIMS, 10 reports of water intoxication were identified, two from endometrial ablations under general anaesthesia and eight from male urological procedures under spinal anaesthesia. The "core" crisis management algorithm detected a problem in seven cases; however, it was deficient in dealing with neurological presentations. Diagnosis of the cause of the incident would have required a specific water intoxication sub-algorithm in eight cases and a hypotension algorithm in a further two cases. Corrective strategies also required a specific sub-algorithm in eight cases, while the hypotension and cardiac arrest sub-algorithms were required in conjunction with the water intoxication sub-algorithm in the remaining two.M T Kluger, S M Szekely, R J Singleton, S C Help

Parental cooperation in an extreme hot environment: natural behaviour and experimental evidence

One of the most apparent examples of cooperation between unrelated individuals is biparental care whereby the male and the female parent share the rearing of the offspring. Theoretical models of care predict that selection should favour biparental care if it substantially improves the survival of the offspring. Although various ecological factors have been proposed to necessitate biparental care, experimental evidence is scant given the challenges of manipulating ecological factors in the natural habitat of animals. We carried out one such experiment in a small shorebird, the Kentish plover, Charadrius alexandrinus, that breeds in an extreme desert environment. Nest cover and thus exposure to solar radiation vary between nests, and we show that parents at exposed nests spent more time incubating than those at nests shaded by a bush (covered nests). Experimental removal and supplementation of nest cover gave results consistent with the observational data; at experimentally exposed nests both males and females increased incubation effort and relieved each other more frequently whereas at experimentally covered nests we observed the opposite. We conclude that exposure to extreme solar radiation influences biparental care and this necessitates parental cooperation in the Kentish plover. Furthermore, since parental care often coevolves with mating strategies, we conjecture that where the environment puts less pressure on the parents and provides the opportunity for reduced care, both mating systems and parental care can diversify over evolutionary time. (C) 2011 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved