Existing data sources for clinical epidemiology: The North Denmark Bacteremia Research Database

Bacteremia is associated with high morbidity and mortality. Improving prevention and treatment requires better knowledge of the disease and its prognosis. However, in order to study the entire spectrum of bacteremia patients, we need valid sources of information, prospective data collection, and complete follow-up. In North Denmark Region, all patients diagnosed with bacteremia have been registered in a population-based database since 1981. The information has been recorded prospectively since 1992 and the main variables are: the patient’s unique civil registration number, date of sampling the first positive blood culture, date of admission, clinical department, date of notification of growth, place of acquisition, focus of infection, microbiological species, antibiogram, and empirical antimicrobial treatment. During the time from 1981 to 2008, information on 22,556 cases of bacteremia has been recorded. The civil registration number makes it possible to link the database to other medical databases and thereby build large cohorts with detailed longitudinal data that include hospital histories since 1977, comorbidity data, and complete follow-up of survival. The database is suited for epidemiological research and, presently, approximately 60 studies have been published. Other Danish departments of clinical microbiology have recently started to record the same information and a population base of 2.3 million will be available for future studies

Identifying Urban Sources as Cause of Elevated Grass Pollen Concentrations using GIS and Remote Sensing

We examine here the hypothesis that during flowering, the grass pollen concentrations at a specific site reflect the distribution of grass pollen sources within a few kilometres of this site.We perform this analysis on data from a measurement campaign in the city of Aarhus (Denmark) using three pollen traps and by comparing these observations with a novel inventory of grass pollen sources. The source inventory is based on a new methodology developed for urbanscale grass pollen sources. The new methodology is believed to be generally applicable for the European area, as it relies on commonly available remote sensing data combined with management information for local grass areas. The inventory has identified a number of grass pollen source areas present within the city domain. The comparison of the measured pollen concentrations with the inventory shows that the atmospheric concentrations of grass pollen in the urban zone reflect the source areas identified in the inventory, and that the pollen sources that are found to affect the pollen levels are located near or within the city domain. The results also show that during days with peak levels of pollen concentrations there is no correlation between the three urban traps and an operational trap located just 60 km away. This finding suggests that during intense flowering, the grass pollen concentration mirrors the local source distribution and is thus a local-scale phenomenon. Model simulations aimed at assessing population exposure to pollen levels are therefore recommended to take into account both local sources and local atmospheric transport, and not to rely only on describing regional to long-range transport of pollen. The derived pollen source inventory can be entered into local-scale atmospheric transport models in combination with other components that simulate pollen release in order to calculate urban-scale variations in the grass pollen load. The gridded inventory with a resolution of 14m is therefore made available as supplementary material to this paper, and the verifying grass pollen observations are additionally available in tabular form

Effect of Aging on the Electrochemical Performance of LSM-YSZ Cathodes

Investigations of degradation mechanisms of solid oxide fuel cells are crucial for achieving a widespread commercialization of the technology. In this work, electrochemical impedance spectroscopy (EIS) was applied for studying the aging effect on LSM-YSZ cathodes exposed to humidified air at 900°C for up to 3000 h. EIS spectra were fitted by a transmission line model for estimating relevant parameters associated with the LSM/YSZ charge transfer reaction and the oxide ion conduction through the YSZ network. For the reference non-aged sample, the ionic conductivity values are the expected ones for YSZ with 1 eV activation energy and no dependency on oxygen partial pressure (pO2), while the charge transfer resistance presents an activation energy of 1.6 eV and is proportional to (pO2)−0.31±0.08. These values agree with those reported in literature, validating the used model. The charge transfer resistance shows no clear tendency with aging time, while the ionic conductivity decreases up to ∼79%. Accordingly, the electrochemically active thickness contracts from 60–135 μm to 45–60 μm. The changes observed in the cathode transport and electrochemical properties are mostly explained by the evolution of the phases present in agreement with results previously reported in the literature.Fil: Baque, Laura Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentina. Technical University of Denmark. Department of Energy Conversion and Storage; DinamarcaFil: Jørgensen, Peter Stanley. Technical University of Denmark. Department of Energy Conversion and Storage; DinamarcaFil: Zhang, Wei. Technical University of Denmark. Department of Energy Conversion and Storage; DinamarcaFil: Hansen, Karin Vels . Technical University of Denmark. Department of Energy Conversion and Storage; DinamarcaFil: Søgaard, Martin. Technical University of Denmark. Department of Energy Conversion and Storage; Dinamarc

Nationwide trends in pneumonia hospitalization rates and mortality, Denmark 1997–2011

SummaryObjectiveTo provide up-to-date population-based data on nationwide trends in pneumonia hospitalization rates and associated 30-day mortality.MethodsUsing medical databases we identified all in-hospital episodes of pneumonia between 1997 and 2011. We computed age- and sex-standardized hospitalization rates of total and first-time pneumonia-related hospitalization and adjusted 30-day mortality rates by calendar year.ResultsAmong 552,528 pneumonia-related hospitalizations in Denmark between 1997 and 2011, 385,985 (69.9%) were first-time events. Total pneumonia hospitalizations increased by 63%, from 4.96 per 1000 population in 1997 to 8.09 in 2011. Rates of first-time pneumonia per 1000 population increased by 33%, from 3.99 in 1997 to 5.31 in 2011. Pneumonia rates stabilized in the mid-00s but primary pneumonia rates increased 16% from 2008 to 2011, most notably among children and young adults. In patients aged ≥80 years the rate of hospitalizations with secondary pneumonia more than doubled during the study period. Average 30-day mortality remained stable at 13%, but increased slightly over time in patients aged ≥80 years.ConclusionsIn an era of smoking cessation and vaccination efforts, pneumonia hospitalization rates are continuously increasing, largely driven by secondary diagnoses and recurrent pneumonia episodes in elderly patients. Thirty-day mortality remains persistently high

Classification of positive blood cultures:computer algorithms versus physicians' assessment - development of tools for surveillance of bloodstream infection prognosis using population-based laboratory databases

BACKGROUND: Information from blood cultures is utilized for infection control, public health surveillance, and clinical outcome research. This information can be enriched by physicians’ assessments of positive blood cultures, which are, however, often available from selected patient groups or pathogens only. The aim of this work was to determine whether patients with positive blood cultures can be classified effectively for outcome research in epidemiological studies by the use of administrative data and computer algorithms, taking physicians’ assessments as reference. METHODS: Physicians’ assessments of positive blood cultures were routinely recorded at two Danish hospitals from 2006 through 2008. The physicians’ assessments classified positive blood cultures as: a) contamination or bloodstream infection; b) bloodstream infection as mono- or polymicrobial; c) bloodstream infection as community- or hospital-onset; d) community-onset bloodstream infection as healthcare-associated or not. We applied the computer algorithms to data from laboratory databases and the Danish National Patient Registry to classify the same groups and compared these with the physicians’ assessments as reference episodes. For each classification, we tabulated episodes derived by the physicians’ assessment and the computer algorithm and compared 30-day mortality between concordant and discrepant groups with adjustment for age, gender, and comorbidity. RESULTS: Physicians derived 9,482 reference episodes from 21,705 positive blood cultures. The agreement between computer algorithms and physicians’ assessments was high for contamination vs. bloodstream infection (8,966/9,482 reference episodes [96.6%], Kappa = 0.83) and mono- vs. polymicrobial bloodstream infection (6,932/7,288 reference episodes [95.2%], Kappa = 0.76), but lower for community- vs. hospital-onset bloodstream infection (6,056/7,288 reference episodes [83.1%], Kappa = 0.57) and healthcare-association (3,032/4,740 reference episodes [64.0%], Kappa = 0.15). The 30-day mortality in the discrepant groups differed from the concordant groups as regards community- vs. hospital-onset, whereas there were no material differences within the other comparison groups. CONCLUSIONS: Using data from health administrative registries, we found high agreement between the computer algorithms and the physicians’ assessments as regards contamination vs. bloodstream infection and monomicrobial vs. polymicrobial bloodstream infection, whereas there was only moderate agreement between the computer algorithms and the physicians’ assessments concerning the place of onset. These results provide new information on the utility of computer algorithms derived from health administrative registries

HortiBot: A System Design of a Robotic Tool Carrier for High-tech Plant Nursing

Danish organic outdoor gardeners today use 50-300 hours per hectare for manual weeding. Through automatic controlling of an existing commercial machine this often heavy and costconsuming weeding will be eliminated. At the same time, a fully-automatic registration of field activities will contribute to the efficient implementation of EU directive 178/2002 concerning traceability in the primary production and thereby enhance the food-safety in the production chain. A radio controlled slope mower is equipped with a new robotic accessory kit. This transforms it into a tool carrier (HortiBot) for high-tech plant nursing for e.g. organic grown vegetables. The HortiBot is capable of passing over several parcels with visible rows autonomously based on a new commercial row detection system from Eco-Dan a/s, Denmark. This paper presents the solutions chosen for the HortiBot with regard to hardware, mechanicalelectrical interfaces and software. Further, the principles from a Quality Function Deployment (QFD) analysis was used to carry out the solicitation, evaluation and selection of most qualified design parameters and specifications attained to a horticultural robotic tool carrier. The QFD analysis provided a specific measure to evaluate each selected parameter in terms of satisfying user requirements and operational performance aspects. Based on a combination of importance rating and competitive priority ratings important user requirements include easy adaptation to field conditions in terms of row distance and parcel size, profitability, minimum crop damage during operation, and reliability. Lesser importance was attributed to affection value, attractive look, the possibility of out of season usage, and the use of renewable energy

Characterization of Intact Proviruses in Blood and Lymph Node from HIV-Infected Individuals Undergoing Analytical Treatment Interruption.

The role of lymphoid tissue as a potential source of HIV-1 rebound following interruption of antiretroviral therapy (ART) is uncertain. To address this issue, we compared the latent viruses obtained from CD4+ T cells in peripheral blood and lymph nodes to viruses emerging during treatment interruption. Latent viruses were characterized by sequencing near-full-length (NFL) proviral DNA and env from viral outgrowth assays (VOAs). Five HIV-1-infected individuals on ART were studied, four of whom participated in a clinical trial of a TLR9 agonist that included an analytical treatment interruption. We found that 98% of intact or replication-competent clonal sequences overlapped between blood and lymph node. In contrast, there was no overlap between 205 latent reservoir and 125 rebound sequences in the four individuals who underwent treatment interruption. However, rebound viruses could be accounted for by recombination. The data suggest that CD4+ T cells carrying latent viruses circulate between blood and lymphoid tissues in individuals on ART and support the idea that recombination may play a role in the emergence of rebound viremia.IMPORTANCE HIV-1 persists as a latent infection in CD4+ T cells that can be found in lymphoid tissues in infected individuals during ART. However, the importance of this tissue reservoir and its contribution to viral rebound upon ART interruption are not clear. In this study, we sought to compare latent HIV-1 from blood and lymph node CD4+ T cells from five HIV-1-infected individuals. Further, we analyzed the contribution of lymph node viruses to viral rebound. We observed that the frequencies of intact proviruses were the same in blood and lymph node. Moreover, expanded clones of T cells bearing identical proviruses were found in blood and lymph node. These latent reservoir sequences did not appear to be the direct origin of rebound virus. Instead, latent proviruses were found to contribute to the rebound compartment by recombination