3,222 research outputs found
Time taken to perform a rapid sequence intubation within a simulated prehospital environment
Abstract: Background. Rapid sequence intubation (RSI) involves inducing unconsciousness and paralysis in rapid succession in order to facilitate endotracheal tube placement. RSI has recently been introduced to the scope of practice of South African prehospital emergency care practitioners (ECPs). Despite this, there remains limited evidence supporting the efficacy and safety of RSI within this context. While in-hospital studies have shown that it can take 20 minutes or more to perform an RSI, little is known about the time taken to perform the procedure in the prehospital setting. Objective. To measure the time taken to perform an RSI in a simulated prehospital environment. Methods. A sample of final-year ECP students were video-recorded performing RSIs on a mannequin within a simulated prehospital environment. Data were gathered through an analysis of the recordings, allowing for the capturing of times taken to complete each of the phases of a RSI. Results. A mean time of 15 minutes 5 seconds was recorded to complete the procedure. This was shorter than times reported for in-hospital studies. Conclusion. RSI is a potentially harmful procedure if improperly performed and has the potential to create delays in transport that may not always be in the patient’s best interest. With a mean time of 15 minutes 5 seconds, the performance of RSI by ECP students in the simulated prehospital environment was faster than expected. Further research is recommended to explore the relationship between the performances observed in this mannequin-based study with those in authentic prehospital settings
Causal Reasoning for Algorithmic Fairness
In this work, we argue for the importance of causal reasoning in creating fair algorithms for decision making. We give a review of existing approaches to fairness, describe work in causality necessary for the understanding of causal approaches, argue why causality is necessary for any approach that wishes to be fair, and give a detailed analysis of the many recent approaches to causality-based fairness
Making Decisions that Reduce Discriminatory Impacts
As machine learning algorithms move into realworld settings, it is crucial to ensure they are
aligned with societal values. There has been
much work on one aspect of this, namely the
discriminatory prediction problem: How can
we reduce discrimination in the predictions themselves? While an important question, solutions to
this problem only apply in a restricted setting, as
we have full control over the predictions. Often
we care about the non-discrimination of quantities we do not have full control over. Thus, we
describe another key aspect of this challenge, the
discriminatory impact problem: How can we
reduce discrimination arising from the real-world
impact of decisions? To address this, we describe
causal methods that model the relevant parts of
the real-world system in which the decisions are
made. Unlike previous approaches, these models not only allow us to map the causal pathway
of a single decision, but also to model the effect
of interference–how the impact on an individual
depends on decisions made about other people.
Often, the goal of decision policies is to maximize a beneficial impact overall. To reduce the
discrimination of these benefits, we devise a constraint inspired by recent work in counterfactual
fairness (Kusner et al., 2017), and give an efficient
procedure to solve the constrained optimization
problem. We demonstrate our approach with an
example: how to increase students taking college
entrance exams in New York City public schools
Seasonal Fish Dispersal in Ephemeral Wetlands of the Florida Everglades
We hypothesized that fishes in short-hydroperiod wetlands display pulses in activity tied to seasonal flooding and drying, with relatively low activity during intervening periods. To evaluate this hypothesis, sampling devices that funnel fish into traps (drift fences) were used to investigate fish movement across the Everglades, U.S.A. Samples were collected at six sites in the Rocky Glades, a seasonally flooded karstic habitat located on the southeastern edge of the Everglades. Four species that display distinct recovery patterns following drought in long-hydroperiod wetlands were studied: eastern mosquitofish (Gambusia holbrooki) and flagfish (Jordanella floridae) (rapid recovery); and bluefin killifish (Lucania goodei) and least killifish (Heterandria formosa) (slow recovery). Consistent with our hypothesized conceptual model, fishes increased movement soon after flooding (immigration period) and just before drying (emigration period), but decreased activity in the intervening foraging period. We also found that eastern mosquitofish and flagfish arrived earlier and showed stronger responses to hydrological variation than either least killifish or bluefin killifish. We concluded that these fishes actively colonize and escape ephemeral wetlands in response to flooding and drying, and display species-specific differences related to flooding and drying that reflect differences in dispersal ability. These results have important implications for Everglades fish metacommunity dynamics
Observation of Colloidal Gold Labelled Platelet Surface Receptors and the Underlying Cytoskeleton Using High Voltage Electron Microscopy and Scanning Electron Microscopy
Fibrinogen conjugated to colloidal gold or colloidal gold-monoclonal anti-glycoprotein IIb/IIIa (fibrinogen receptor) was used to label the receptor on platelets. Whole mount preparations were examined by stereo pair high voltage electron microscopy and then by scanning electron microscopy to determine the feasibility of this approach in detecting the number of receptors and their location relative to the cytoskeletal and surface structure. Both the ligand-gold and antibody-gold labels were effective. The relative numbers of receptors could be seen and their relationship to cytoskeletal structure could be determined. Marked differences in receptor number and distribution were observed when platelets in different stages of activation were compared. In co-cultured macrophages and platelets, receptors were found exclusively on platelets or on pieces of platelet membrane adherent to macrophages
Efficient magneto-optical trapping of Yb atoms with a violet laser diode
We report the first efficient trapping of rare-earth Yb atoms with a
high-power violet laser diode (LD). An injection-locked violet LD with a 25 mW
frequency-stabilized output was used for the magneto-optical trapping (MOT) of
fermionic as well as bosonic Yb isotopes. A typical number of
atoms for Yb with a trap density of cm was
obtained. A 10 mW violet external-cavity LD (ECLD) was used for the
one-dimensional (1D) slowing of an effusive Yb atomic beam without a Zeeman
slower resulting in a 35-fold increase in the number of trapped atoms. The
overall characteristics of our compact violet MOT, e.g., the loss time of 1 s,
the loading time of 400 ms, and the cloud temperature of 0.7 mK, are comparable
to those in previously reported violet Yb MOTs, yet with a greatly reduced cost
and complexity of the experiment.Comment: 5 pages, 3 figures, 1 table, Phys. Rev. A (to be published
Measurement of Linear Stark Interference in 199Hg
We present measurements of Stark interference in the 6
6 transition in Hg, a process whereby a static electric field
mixes magnetic dipole and electric quadrupole couplings into an electric
dipole transition, leading to -linear energy shifts similar to those
produced by a permanent atomic electric dipole moment (EDM). The measured
interference amplitude, = = (5.8 1.5) (kV/cm), agrees with relativistic, many-body predictions and
confirms that earlier central-field estimates are a factor of 10 too large.
More importantly, this study validates the capability of the Hg EDM
search apparatus to resolve non-trivial, controlled, and sub-nHz Larmor
frequency shifts with EDM-like characteristics.Comment: 4 pages, 4 figures, 1 table; revised in response to reviewer comment
Determination of Trichinella Spiralis Specific IgM and IgG Antibody Titers and Total IgE Concentration in 2,3,7,8-Tetrachlorodibenzo-P-Dioxin Exposed Rats
Immunotoxic chemicals are a concern because of the role the immune system plays in maintaining health. The immunotoxicity of TCDD has been well documented as the immune system is highly sensitive to TCDD exposure (Smialowicz et al., 1994). In host resistance studies, functional immune system changes following TCDD exposure have been demonstrated to lead to an increase in susceptibility to bacterial, viral and parasitic diseases. In order to investigate whether TCDD treatment decreased parasite antigen-specific antibody responses, sera from adult male F344 rats dosed with 30 μg/kg TCDD or corn oil and infected with T. spiralis were analyzed at days 7, 9, 11, 14, and 28 post infection by ELISA for T. spiralis specific IgM and IgG antibody titers and total IgE concentration. An enhancement in the treated group of the IgM antibody response at days 7 and 14 (p<0.05) was observed. A slight suppression of the day 9 IgM antibody response was also noted in the treated group (p<0.05). Additionally, the IgG day 9 titer reflected a suppressed antibody response in the treated group (p<0.05). No other treatment related effects were observed in the adult rats. Aged rats were also investigated under the same parameters at days 11 and 28 post infection. No observable changes in antibody levels were recorded for the aged rats. These data were generated to further evaluate the link between decreased parasite antigen specific antibody responses and treatment with TCDD in rats.Master of Science in Public Healt
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