Does Energy Consumption Respond to Price Shocks? Evidence from a Regression-Discontinuity Design

This paper exploits unique features of a recently introduced tariff schedule for natural gas in Buenos Aires to estimate the short-run impact of price shocks on residential energy utilization. The schedule induces a non-linear and nonmonotonic relationship between households accumulated consumption and unit prices, thus generating an exogenous source of variation in perceived prices, which is exploited in a regression-discontinuity design. The estimates reveal that a price increase in the utility bill received by consumers causes a substantial and prompt decline in gas consumption. Hence they suggest that policy interventions via the price mechanism, such as price caps and subsidies, are powerful instruments to influence residential energy utilization patterns, even within a short time span

Outbreak of New Delhi metallo-β-lactamase carbapenemase-producing Pseudomonas aeruginosa infections in a Southern California hospital

BackgroundCarbapenemase-producing carbapenem-resistant Pseudomonas aeruginosa (CP-CRPA) is a major public health threat due to limited treatment options and high transmissibility. Though widespread globally, few instances of locally transmitted New Delhi metallo-β-lactamase (NDM)-producing CP-CRPA have been documented in the United States. Here, a cluster of locally transmitted NDM-1 CP-CRPA infections in Southern California is reported.MethodsEpidemiologic investigations involving both patient screening and environmental surveillance by microbiological culture, carbapenemase testing, and bacterial whole-genome sequencing were conducted.ResultsThrough extensive epidemiologic investigations, a sink environmental reservoir was identified. A genetically unique strain of NDM-CRPA was identified to be transmitted among seven patients in a single hospital over the course of 1.5 years. Changes in antimicrobial resistance genes harbored by a mobile genetic element were identified between the index and later cases, and the gene encoding NDM-1 resided within a mobile genetic element on the chromosome displaying evidence of widespread transmission between different species. Several interventions were implemented, including sink P-trap replacement and disinfectant against Pseudomonas biofilms. No additional cases were identified after the interventions.ConclusionsImplementation of real-time pathogen surveillance enabled effective response to an ongoing outbreak that involved environmental sampling, microbiological testing, whole-genome sequencing, facility management, and updated infection prevention policies

Measuring Residential Energy Efficiency Improvements with DEA

This paper measures energy efficiency improvements of US single-family homes between 1997 and 2001 using a two-stage procedure. In the first stage, an indicator of energy efficiency is derived by means of Data Envelopment Analysis (DEA), and the analogy between the DEA estimator and traditional measures of energy efficiency is demonstrated. The second stage employs a bootstrapped truncated regression technique to decompose the variation in the obtained efficiency estimates into a climatic component and factors attributed to efficiency improvements. Results indicate a small but significant improvement of energy efficiency over the studied time interval, mainly accounted for by fuel oil and natural gas users

Control of Mycobacterium fortuitum and Mycobacterium intracellulare infections with respect to distinct granuloma formations in livers of BALB/c mice

Mycobacterium fortuitum is a rapidly growing nontuberculous Mycobacterium that can cause a range of diseases in humans. Complications from M. fortuitum infection have been associated with numerous surgical procedures. A protective immune response against pathogenic mycobacterial infections is dependent on the granuloma formation. Within the granuloma, the macrophage effector response can inhibit bacterial replication and mediate the intracellular killing of bacteria. The granulomatous responses of BALB/c mice to rapidly and slowly growing mycobacteria were assessed in vivo and the bacterial loads in spleens and livers from M. fortuitum and Mycobacterium intracellulare-infected mice, as well as the number and size of granulomas in liver sections, were quantified. Bacterial loads were found to be approximately two times lower in M. fortuitum-infected mice than in M. intracellulare-infected mice and M. fortuitum-infected mice presented fewer granulomas compared to M. intracellulare-infected mice. These granulomas were characterized by the presence of Mac-1+ and CD4+ cells. Additionally, IFN-γmRNA expression was higher in the livers of M. fortuitum-infected mice than in those of M. intracellulare-infected mice. These data clearly show that mice are more capable of controlling an infection with M. fortuitum than M. intracellulare. This capacity is likely related to distinct granuloma formations in mice infected with M. fortuitum but not with M. intracellulare

Process model for BIM-based MEP design

Abstract Planning quality is a key aspect for the development of sustainable buildings. This particularly applies to mechanical, electrical and plumbing (MEP) systems, which have a high impact on the building performance. The design of these systems considerably affects construction and operational costs. Moreover, it has a substantial impact on the consumption of resources such as energy or water and also on the building quality in terms of user satisfaction. Building information modeling (BIM) is a method capable of substantially improving the quality of MEP design. This requires adequate component models as well as processes describing the proper use of these models in a BIM project. This paper presents a Business Process Model and Notation (BPMN) model which describes the required interactions between project stakeholders during the design phase of a geothermal heat pump system. It describes the roles, tasks and responsibilities of the involved stakeholders and outlines which kind of information is required from whom at which point of time. The specific activities of the stakeholders are linked by information flows. In addition to the process model, a set of parameters describing a heat pump is presented. The parameters can be used as attributes in a BIM model. Each parameter is assigned to the design phase in which it is needed for the first time. This establishes a link between the attributes in the BIM model and the process model. Both, the process model and the parameter set were evaluated by MEP experts.</jats:p

Evaluation of a Bulk Drying Model for Peanuts1

Abstract Results of a peanut bulk drying model, PEADRY8, have been compared with experimental test results for Virginia-type peanuts. The model describes the peanut pod as two separate components with moisture movement in both liquid and vapor form. The Henderson equation was used to describe the equilibrium moisture contents of the kernel and the hull. The following conclusions were drawn: (1) predicted drying times averaged 11% longer than the observed values; (2) predicted kernel moisture contents at the top of the wagons averaged 5% less than the measured values; (3) predicted hull moisture contents at the top of the wagons averaged 17% higher than the observed values; (4) predicted hull final moisture contents at the top of the wagons average 21% higher than measured values and (5) predicted exhaust air temperatures averaged 1% higher than measured values. An attempt was made to improve the fit of the observed and simulated results by changing the equation to describe the equilibrium moisture contents. The Chung-Pfost equation, compared to the Henderson equation, was more accurate in describing the hull moisture content and less accurate in describing the kernel moisture content history. Changing the reference air flow rate of the thin-layer drying relationship did not give a better fit between the observed and predicted data. Several drying simulations were found to be very sensitive to small changes in either wet-bulb or dry-bulb temperature. Small errors in wet-bulb temperature measurement could account for the predicted drying times for six experiments which were excessively long relative to observed values.</jats:p