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The “Stop the Bleed” campaign advocates for non-medical personnel to be trained in basic hemorrhage control. However, it is not clear what type of education or the duration of instruction needed to meet that requirement. The objective of this study was to determine the impact of a brief hemorrhage control educational curriculum on the willingness of laypersons to respond during a traumatic emergency.
This “Stop the Bleed” education initiative was conducted by the University of Texas Health San Antonio Office of the Medical Director (San Antonio, Texas USA) between September 2016 and March 2017. Individuals with formal medical certification were excluded from this analysis. Trainers used a pre-event questionnaire to assess participants knowledge and attitudes about tourniquets and responding to traumatic emergencies. Each training course included an individual evaluation of tourniquet placement, 20 minutes of didactic instruction on hemorrhage control techniques, and hands-on instruction with tourniquet application on both adult and child mannequins. The primary outcome in this study was the willingness to use a tourniquet in response to a traumatic medical emergency.
Of 236 participants, 218 met the eligibility criteria. When initially asked if they would use a tourniquet in real life, 64.2% (140/218) responded “Yes.” Following training, 95.6% (194/203) of participants responded that they would use a tourniquet in real life. When participants were asked about their comfort level with using a tourniquet in real life, there was a statistically significant improvement between their initial response and their response post training (2.5 versus 4.0, based on 5-point Likert scale; P<.001).
In this hemorrhage control education study, it was found that a short educational intervention can improve laypersons’ self-efficacy and reported willingness to use a tourniquet in an emergency. Identified barriers to act should be addressed when designing future hemorrhage control public health education campaigns. Community education should continue to be a priority of the “Stop the Bleed” campaign.
RossEM, RedmanTT, MappJG, BrownDJ, TanakaK, CooleyCW, KharodCU, WamplerDA. Stop the Bleed: The Effect of Hemorrhage Control Education on Laypersons’ Willingness to Respond During a Traumatic Medical Emergency. Prehosp Disaster Med. 2018;33(2):127–132.
Many snow models have been developed for various applications such as hydrology, global atmospheric circulation models and avalanche forecasting. The degree of complexity of these models is highly variable, ranging from simple index methods to multi-layer models that simulate snow-cover stratigraphy and texture. In the framework of the Snow Model Intercomparison Project (SnowMIP), 23 models were compared using observed meteorological parameters from two mountainous alpine sites. The analysis here focuses on validation of snow energy-budget simulations. Albedo and snow surface temperature observations allow identification of the more realistic simulations and quantification of errors for two components of the energy budget: the net short- and longwave radiation. In particular, the different albedo parameterizations are evaluated for different snowpack states (in winter and spring). Analysis of results during the melting period allows an investigation of the different ways of partitioning the energy fluxes and reveals the complex feedbacks which occur when simulating the snow energy budget. Particular attention is paid to the impact of model complexity on the energy-budget components. The model complexity has a major role for the net longwave radiation calculation, whereas the albedo parameterization is the most significant factor explaining the accuracy of the net shortwave radiation simulation.
Historical and reconstructed snow-cover data show evidence of a gradual increase in snow cover over the continental interior of North America (NA) during much of the 20th century, primarily in response to increasing snowfall. A rapid decrease in Canadian-prairies snow cover after 1970 is not observed over the Great Plains. Analysis of snow-cover-climate relationships revealed systematic increases in the sensitivity of snow cover to Northern Hemisphere (NH) temperatures over the 1940-65 period. This change is mainly due to an increase in snowfall-temperature sensitivity during this period. Seasonal analysis revealed that the observed increase in snow-cover and snowfall temperature sensitivity is primarily a spring phenomenon. A marked increase in the importance of the spring period is observed around 1960, which coincides with a well-documented change in atmospheric circulation over NA. The post-1960 period is characterized by a significant inverse relationship between snow cover and hemispheric air temperature over the Canadian prairies and northern Great Plains regions.
Observed and reconstructed snow-cover duration data from stations covering
southern Canada, the Great Plains, the former Soviet Union and China were
used to reconstruct spring snow-covered area over North America (NA) and
Eurasia from 1915 to 1985. A combination of nine regions from NA and five
from Eurasia were able to explain 81% and 67%, respectively, of the variance
in satellite-derived sprint; snow-covered area (SCA) for each continent. The
results suggested sprint; SCA had decreased significantly in Eurasia this
century, but there was no evidence of a similar long-term decrease in NA
spring SCA. Considerable caution should be used when interpreting these
results because of the short period of calibration, and because of the
less-than-optimal distribution of station data. Nonetheless, the
reconstructed results are consistent with observed spring-temperature
trends, which show a significant increase over Eurasia, but none Over
We consider the coupon collection problem, where each coupon is one of the types 1,…,s with probabilities given by a vector 𝒑. For specified numbers r1,…,rs, we are interested in finding 𝒑 that minimizes the expected time to obtain at least ri type-i coupons for all i=1,…,s. For example, for s=2, r1=1, and r2=r, we show that p1=(logr−log(logr))∕r is close to optimal.
To analyze antipsychotic prescribing patterns in a UK high security hospital (HSH) that treats seriously violent men with either schizophrenia or personality disorder and examine how different groups consented to treatment and prescribing for metabolic conditions. We hypothesized that there would be high prevalence of antipsychotic polypharmacy, and high-dose antipsychotic and clozapine prescribing.
HSHs treat seriously violent, mentally disordered offenders, and the extant literature on prescribing patterns in forensic settings is sparse.
Prescribing and clinical data on all 189 patients in a UK HSH were collected from the hospital’s databases. Data were analyzed using SPSS.
The population was split into the following groups: schizophrenia spectrum disorder (SSD-only), personality disorder (PD-only), and comorbid schizophrenia spectrum disorder and PD. The majority (93.7%) of all patients were prescribed at least one antipsychotic, and (27.5%) were on clozapine. Polypharmacy was prevalent in 22.2% and high-dose antipsychotic in 27.5%. Patients on clozapine were more likely to be prescribed antidiabetic, statins, or antihypertensive medication. Patients in the PD-only group were more likely to be deemed to have the capacity to consent to treatment and be prescribed clozapine in contrast to the SSD-only group.
Rates of clozapine and high-dose antipsychotic prescribing were higher than in other psychiatric settings, while polypharmacy prescribing rates were lower. Higher clozapine prescribing rates may be a function of a treatment-resistant and aggressive population. A higher proportion of PD-only patients consented to treatment and received clozapine compared with in-house SSD-only as well as other psychiatric settings. Implications of the findings are discussed.
A number of studies have demonstrated the anti-aggressive properties of clozapine in schizophrenia and its positive effect in borderline personality disorder. There is no published literature on the treatment of antisocial personality disorder (ASPD) with clozapine. We present a case series of 7 patients with primary ASPD and high psychopathic traits treated with clozapine, having a significant history of serious violence and currently detained in a UK based high-security hospital.
A retrospective review of case notes was carried out to formulate Clinical Global Impression (CGI) scores and record incidents of violence and aggression. Effect on specific symptom domains (cognitive-perceptual, impulsive-behavioural dyscontrol, affective dysregulation) was also noted. Metabolic parameters and serum clozapine levels were also sampled.
All 7 patients showed significant improvement on clozapine. It was shown to benefit all symptom domains, especially impulsive behavioral dyscontrol and anger. The number of violent incidents committed by 6 of the 7 patients reduced significantly, and all patients’ risk of violence reduced. Clozapine serum levels for 6 of the 7 patients were in the range 150–350 ng/mL.
Clozapine is of benefit in reducing the clinical severity of ASPD. It improved all symptom domains, especially impulsive-behavioral dyscontrol and anger, and reduced levels of aggression and violence, especially at lower doses (serum levels <350 ng/m). To our knowledge, this is the first account of clozapine treatment in patients with ASPD and high psychopathy.
A fundamental understanding of the processes that occur during early stages of corrosion is traditionally limited by the dearth of techniques that probe the liquid-solid interface with both high spatial resolution and microstructural detail such as grain size and orientation. Here, we demonstrate that with a microfluidic liquid flow cell holder, we can track the progress of corrosion in situ in Al thin films with transmission electron microscopy (TEM). To mitigate the loss of resolution caused by imaging through liquid, we developed a method in which the liquid is temporarily de-wetted from the entire windowed area by switching the liquid stream from pure water to a mixture of ethanol and water. In the de-wetted region, we then collected images of the film microstructure with high spatial resolution over regular intervals while maintaining a low electron flux over the imaged area to minimize beam-induced effects. For as-deposited films, we find that the corrosion progresses in a fractal manner, consistent with reported behavior for films studied in water with low iron and chloride concentrations. For films that were subjected to rapid thermal annealing, we observe a higher density of pitting events, which we attribute to defects created by thermal stress in the oxide film. Furthermore, we observe that the pits can form at multiple locations in a single grain and are not confined to grain boundaries.
The search for durable dyes led several past civilizations to develop artificial pigments. Maya Blue (MB), manufactured in pre-Columbian Mesoamerica, is one of the best known examples of an organic-inorganic hybrid material. Its durability is due to the unique association of indigo molecule and palygorskite, a particular fibrous clay occurring in Yucatan. Despite 50 years of sustained interest, the microscopic structure of MB and its relation to the durability remain open questions. Combining new thermogravimetric and synchrotron X-ray diffraction analyses, we show that indigo molecules can diffuse into the channel of the palygorskite during the heating process, replacing zeolitic water and stabilizing the room temperature phases of the clay.
Near-edge and extended x-ray absorption fine structure measurements from a wide variety of H-passivated porous Si samples and oxidized Si nanocrystals, combined with electron microscopy, ir-absorption, α-recoil, and luminescence emission data, provide a consistent structural picture of the species responsible for the luminescence observed in these systems. For luminescent porous Si samples peaking in the visible region, i. e., ≤700nm, their mass-weighted-average structures are determined here to be particles–not wires, whose short-range character is crystalline – not amorphous, and whose dimensions – typically <15 Å – are significantly smaller than previously reported or proposed. These results depend only on sample luminescence behavior, not on sample preparation details, and thus have general implications in describing the mechanism responsible for visible luminescence in porous silicon. New results are also presented which demonstrate that the observed luminescence is unrelated to either the photo-oxidized Si species in porous Si or the interfacial suboxide species in the Si nanocrystals.
The electromigration failure mode and failure rate during accelerated electromigration testing is expected to be strongly affected by the mechanical stress state of Al lines, since tensile stress and compressive stress states favor void growth and hillock formations (extrusions), respectively. During electromigration testing, the mechanical stress state or evolution of mechanical stress of an interconnect is a function of current density and temperature, the two principal variables in electromigration testing. In our experiments, we have observed two different electromigration failure modes by varying the current density and temperatures where (i) the passivated Al lines tested at high current density and high temperatures failed by extrusion or hillock type failure and (ii) the interconnect lines tested at low current density and moderate temperature failed by voiding. A mechanical stress model which incorporates both the thermally generated stress and electromigration induced mechanical stress is invoked to explain the electromigration failure mode selection observed in our experiments.
Interconnect metallizations used in advanced integrated circuits typically use an Al-alloy sputterdeposited onto a Ti barrier layer. The Ti and Al react above ∼ 400°C to form TiAl3, which affects the stress evolution of the metal stack during thermal cycling. This paper describes results of thin film experiments performed on Ti/Al-alloy bilayer films. Two Al alloys were studied: Al-I%Cu and Al-0.5%Cu-1%Si. The rate of TiAl3 formation at 430°C was determined for both alloys and used to relate TiAl3 formation to the stress evolution of the film stacks during thermal cycling. The dominant effect of the TiAl3 intermetallic formation on stress arises from a change in the stress-temperature behavior of the film stack, due to a change in the yield behavior, effective modulus, and thermal expansion coefficient of the stack. The presence of Si in the Al-alloy markedly reduces both the rate of TiAl3 formation and the resulting change in composite stress.
We have measured the stress in Mo/Si multilayer films deposited by magnetron sputtering, using the wafer-curvature technique, and find a strong dependence on background pressure. For multilayers containing 40 bilayers of ˜4.3 nm Si layers and ˜2.6 nm Mo layers, the stress increases from approximately −280 MPa (compressive) to −450 MPa as the background pressure in the deposition chamber (i.e., measured just prior to deposition) decreases from 1.0 } 10−5 to 6.0 } 10−8 torr. For multilayers of the same period but with thicker Mo layers, the dependence on background pressure is even stronger. X-ray (λ = 0.154 nm) diffraction measurements reveal a slight increase in interfacial roughness for films deposited at high background pressure. Atomic concentrations of incorporated oxygen and carbon, measured with Auger electron spectroscopy, were found to be less than ˜0.5 at.% for all samples. However, the average hydrogen concentration, as determined from forward-recoil-scattering measurements, was found to vary from ˜0.3 at.% to ˜1.6 at.%, increasing with both background pressure and Mo layer thickness. We discuss possible mechanisms for the observed dependence of film stress on background pressure, including gas incorporation and the affect of residual gas atoms on adatom mobility.