221 research outputs found
Health-Related Philanthropy: Toward Understanding the Relationship Between the Donation of the Body (and Its Parts) and Traditional Forms of Philanthropic Giving
The academic study of philanthropy has focused on the public good from private action
and includes the study of the public good of improving health and studies of the various
determinants of giving. Yet one very obvious act of giving in the health field has been
largely neglected in philanthropic studies: the donation of the body, such as blood and
tissue donation, organ donation, and the donation of oneâs body for medical research or
education. In August 2003, a research team at the Indiana University Center for
Bioethics conducted a study of these two aspects of philanthropy as part of a project
titled Health Related Philanthropy: The Donation of the Body (and Parts Thereof). This
article describes the project and summarizes the results of a national survey conducted
as part of that project
El Nino Influence on Holocene Reef Accretion in Hawai'i
New observations of reef accretion from several locations show that
in Hawai'i accretion during early to middle Holocene time occurred in areas
where today it is precluded by the wave regime, suggesting an increase in wave
energy. Accretion of coral and coralline algae reefs in the Hawaiian Islands today
is largely controlled by wave energy. Many coastal areas in the main Hawaiian
Islands are periodically exposed to large waves, in particular from North
Pacific swell and hurricanes. These are of sufficient intensity to prevent modern
net accretion as evidenced by the antecedent nature of the seafloor. Only in
areas sheltered from intense wave energy is active accretion observed. Analysis
of reef cores reveals patterns of rapid early Holocene accretion in several locations
that terminated by middle Holocene time, ca. 5000 yr ago. Previous analyses
have suggested that changes in Holocene accretion were a result of reef
growth "catching up" to sea level. New data and interpretations indicate that
the end of reef accretion in the middle Holocene may be influenced by factors in
addition to sea level. Reef accretion histories from the islands of Kaua'i, O'ahu,
and Moloka'i may be interpreted to suggest that a change in wave energy contributed
to the reduction or termination of Holocene accretion by 5000 yr ago
in some areas. In these cases, the decrease in reef accretion occurred before the
best estimates of the decrease in relative sea-level rise during the mid-Holocene
high stand of sea level in the main Hawaiian Islands. However, reef accretion
should decrease following the termination of relative sea-level rise (ca. 3000 yr
ago) if reef growth were "catching up" to sea level. Evidence indicates that rapid
accretion occurred at these sites in early Holocene time and that no permanent
accretion is occurring at these sites today. This pattern persists despite the
availability of hard substrate suitable for colonization at a wide range of depths
between -30 m and the intertidal zone. We infer that forcing other than relative
sea-level rise has altered the natural ability to support reef accretion on
Hawaiian insular shelves. The limiting factor in these areas today is wave
energy. Numbers of both large North Pacific swell events and hurricanes in
Hawai'i are greater during El Nino years. We infer that if these major reef-limiting
forces were suppressed, net accretion would occur in some areas in
Hawai'i that are now wave-limited. Studies have shown that El Nino/Southern
Oscillation (ENSO) was significantly weakened during early-mid Holocene
time, only attaining an intensity similar to the current one ca. 5000 yr ago. We
speculate that this shift in ENSO may assist in explaining patterns of Holocene
Hawaiian reef accretion that are different from those of the present and apparently
not related to relative sea-level rise
Preliminary Evaluation of a Laparoscopic Common Bile Duct Simulator for Pediatric Surgical Education
Purpose: Laparoscopic common bile duct exploration (LCBDE) decreases overall costs and length of stay in patients with choledocolithiasis. However, utilization of LCBDE remains low. We sought to evaluate a previously developed general surgery LCBDE simulator among a cohort of pediatric surgical trainees. The study purpose was to evaluate the content validity of an LCBDE simulator to support or refute its use in pediatric surgery education. Materials and Methods: After IRB exempt determination, 30 participants performed a transcystic LCBDE using a previously developed simulator and evaluated the simulator using a self-reported 28-item instrument. The instrument consisted of two primary domains (Quality and Ability to Perform) that were rated using twenty-five 4-point rating scales and one 4-point global rating scale. Validity evidence relevant to test content was evaluated using a many-facet Rasch model. Interitem consistency was estimated using Cronbach's alpha. P?Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140153/1/lap.2016.0248.pd
The CATFISH study protocol: an evaluation of a water fluoridation scheme
Abstract
Background
Tooth decay is the commonest disease of childhood. We have known for over 90Â years that fluoride can prevent tooth decay; it is present in nearly all toothpastes and can be provided in mouthwashes, gels and varnishes. The oldest method of applying fluoride is via the water supply at a concentration of 1 part per million. The two most important reviews of water fluoridation in the United Kingdom (the York Review and MRC Report on water fluoridation and health) concluded that whilst there was evidence to suggest water fluoridation provided a benefit in caries reduction, there was a need to improve the evidence base in several areas.
Methods/Design
This study will use a natural experiment to assess the incidence of caries in two geographical areas, one in which the water supply is returned to being fluoridated following a discontinuation of fluoridation and one that continues to have a non-fluoridated water supply. The oral health of two discrete study populations will be evaluated - those born 9Â months after the water fluoridation was introduced, and those who were in their 1st year of school after the introduction of fluoridated water. Both populations will be followed prospectively for 5Â years using a census approach in the exposed group along with matched numbers recruitment in a non-exposed control. Parents of the younger cohort will complete questionnaires every 6Â months with child clinical examination at ages 3 and 5, whilst the older cohort will have clinical examinations only, at approximately 5, 7 and 11Â years old.
Discussion
This project provides a unique opportunity to conduct a high quality evaluation of the reintroduction of a water fluoridation scheme, which satisfies the inclusion criteria stipulated by the York systematic review and can address the design issues identified in the MRC report. The research will make a major contribution to the understanding of the costs and effects of water fluoridation in the UK in the 21st Century. Its findings will help inform UK policy on this important public health intervention and may have a significant impact on public health policy in other developed countries. There is currently true equipoise in relation to the effectiveness of water fluoridation in contemporary populations and while the biological plausibility is well established, there is a need to examine impact on the changing epidemiological status of dental decay
Organisation and Governance of Urban Energy Systems:District Heating and Cooling in the UK
International audienc
Upper mantle temperature and the onset of extension and break-up in Afar, Africa
It is debated to what extent mantle plumes play a role in continental rifting and eventual break-up. Afar lies at the northern end of the largest and most active present-day continental rift, where the East African Rift forms a triple junction with the Red Sea and Gulf of Aden rifts. It has a history of plume activity yet recent studies have reached conflicting conclusions on whether a plume still contributes to current Afar tectonics. A geochemical study concluded that Afar is a mature hot rift with 80 km thick lithosphere, while seismic data have been interpreted to reflect the structure of a young, oceanic rift basin above mantle of normal temperature. We develop a self-consistent forward model of mantle flow that incorporates melt generation and retention to test whether predictions of melt chemistry, melt volume and lithosphereâasthenosphere seismic structure can be reconciled with observations. The rare- earth element composition of mafic samples at the Erta Ale, Dabbahu and Asal magmatic segments can be used as both a thermometer and chronometer of the rifting process. Low seismic velocities require a lithosphere thinned to 50 km or less. A strong positive impedance contrast at 50 to 70 km below the rift seems linked to the melt zone, but is not reproduced by isotropic seismic velocity alone. Combined, the simplest interpretation is that mantle temperature below Afar is still elevated at 1450âŠC, rifting started around 22â23 Ma, and the lithosphere has thinned from 100 to 50 km to allow significant decompressional melting
Unmanned Aerial Vehicles for High-Throughput Phenotyping and Agronomic Research
Advances in automation and data science have led agriculturists to seek real-time, high-quality, high-volume crop data to accelerate crop improvement through breeding and to optimize agronomic practices. Breeders have recently gained massive data-collection capability in genome sequencing of plants. Faster phenotypic trait data collection and analysis relative to genetic data leads to faster and better selections in crop improvement. Furthermore, faster and higher-resolution crop data collection leads to greater capability for scientists and growers to improve precision-agriculture practices on increasingly larger farms; e.g., site-specific application of water and nutrients. Unmanned aerial vehicles (UAVs) have recently gained traction as agricultural data collection systems. Using UAVs for agricultural remote sensing is an innovative technology that differs from traditional remote sensing in more ways than strictly higher-resolution images; it provides many new and unique possibilities, as well as new and unique challenges. Herein we report on processes and lessons learned from year 1-the summer 2015 and winter 2016 growing seasons-of a large multidisciplinary project evaluating UAV images across a range of breeding and agronomic research trials on a large research farm. Included are team and project planning, UAV and sensor selection and integration, and data collection and analysis workflow. The study involved many crops and both breeding plots and agronomic fields. The project's goal was to develop methods for UAVs to collect high-quality, high-volume crop data with fast turnaround time to field scientists. The project included five teams: Administration, Flight Operations, Sensors, Data Management, and Field Research. Four case studies involving multiple crops in breeding and agronomic applications add practical descriptive detail. Lessons learned include critical information on sensors, air vehicles, and configuration parameters for both. As the first and most comprehensive project of its kind to date, these lessons are particularly salient to researchers embarking on agricultural research with UAVs
A predictive model relating daily fluctuations in summer temperatures and mortality rates
<p>Abstract</p> <p>Background</p> <p>In the context of climate change, an efficient alert system to prevent the risk associated with summer heat is necessary. The authors' objective was to describe the temperature-mortality relationship in France over a 29-year period and to define and validate a combination of temperature factors enabling optimum prediction of the daily fluctuations in summer mortality.</p> <p>Methods</p> <p>The study addressed the daily mortality rates of subjects aged over 55 years, in France as a whole, from 1975 to 2003. The daily minimum and maximum temperatures consisted in the average values recorded by 97 meteorological stations. For each day, a cumulative variable for the maximum temperature over the preceding 10 days was defined.</p> <p>The mortality rate was modelled using a Poisson regression with over-dispersion and a first-order autoregressive structure and with control for long-term and within-summer seasonal trends. The lag effects of temperature were accounted for by including the preceding 5 days. A "backward" method was used to select the most significant climatic variables. The predictive performance of the model was assessed by comparing the observed and predicted daily mortality rates on a validation period (summer 2003), which was distinct from the calibration period (1975â2002) used to estimate the model.</p> <p>Results</p> <p>The temperature indicators explained 76% of the total over-dispersion. The greater part of the daily fluctuations in mortality was explained by the interaction between minimum and maximum temperatures, for a day <it>t </it>and the day preceding it. The prediction of mortality during extreme events was greatly improved by including the cumulative variables for maximum temperature, in interaction with the maximum temperatures. The correlation between the observed and estimated mortality ratios was 0.88 in the final model.</p> <p>Conclusion</p> <p>Although France is a large country with geographic heterogeneity in both mortality and temperatures, a strong correlation between the daily fluctuations in mortality and the temperatures in summer on a national scale was observed. The model provided a satisfactory quantitative prediction of the daily mortality both for the days with usual temperatures and for the days during intense heat episodes. The results may contribute to enhancing the alert system for intense heat waves.</p
Reliability of dynamic contrast-enhanced magnetic resonance imaging data in primary brain tumours: a comparison of Tofts and shutter speed models
Purpose To investigate the robustness of pharmacokinetic modelling of DCE-MRI brain tumour data and to ascertain reliable perfusion parameters through a model selection process and a stability test. Methods DCE-MRI data of 14 patients with primary brain tumours were analysed using the Tofts model (TM), the extended Tofts model (ETM), the shutter speed model (SSM) and the extended shutter speed model (ESSM). A no-effect model (NEM) was implemented to assess overfitting of data by the other models. For each lesion, the Akaike Information Criteria (AIC) was used to build a 3D model selection map. The variability of each pharmacokinetic parameter extracted from this map was assessed with a noise propagation procedure, resulting in voxel-wise distributions of the coefficient of variation (CV). Results The model selection map over all patients showed NEM had the best fit in 35.5% of voxels, followed by ETM (32%), TM (28.2%), SSM (4.3%) and ESSM (<0.1%). In analysing the reliability of Ktrans, when considering regions with a CV<20%, â25% of voxels were found to be stable across all patients. The remaining 75% of voxels were considered unreliable. Conclusions The majority of studies quantifying DCE-MRI data in brain tumours only consider a single model and whole-tumour statistics for the output parameters. Appropriate model selection, considering tissue biology and its effects on blood brain barrier permeability and exchange conditions, together with an analysis on the reliability and stability of the calculated parameters, is critical in processing robust brain tumour DCE-MRI data
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