Prehospital advanced airway management practices by advanced life support providers: A retrospective observational study of emergency medical service providers in South Africa

Introduction: The skill of endotracheal intubation to achieve a definitive airway for critically ill and injured patients in the prehospital setting is frequently performed by advanced life support providers. Several methods may be utilised, including intubation without the use of medication, the use of sedatives or a rapid sequence intubation. There is a paucity of data available that assesses prehospital advanced airway intubation practices in South Africa. The aim of this study is to describe the advanced airway management practices of advanced life support providers across South Africa. Methods: A retrospective, observational study method was used (chart review). Electronic patient care records were sourced from private and public emergency medical services companies and collated accordingly. Results: A total of 704 cases were included. Intubation during cardiac arrest was the most common approach to airway management (n=280, 40%) followed by rapid sequence intubation (n=202, 28%), medication-facilitated intubations (n=152, 22%) and a nomedication approach (n=70, 10%). Successful intubation using an endotracheal tube was reported in 197 (98%) of rapid sequence intubation cases, 134 (88%) of the medication facilitated cases, 61 (87%) of no-medication cases and 228 (81%) of cardiac arrest cases. A first-pass success rate was described in 260 (79%) cases, with the cardiac arrest group having a first-pass success of 85%, followed by the rapid sequence intubation group (83%), the nomedication group (71%) and the medication facilitated group (61%). Hypotension and cardiac arrest were the most common adverse events. A total of 496 (70%) patients were alive at hospital handover. The average scene time and transportation time was 42 minutes and 24 minutes respectively for the rapid sequence intubation group, 42min and 27min for the medication facilitated group, 44min and 25min for the no-medication group and 57min and 16min for the cardiac arrest group. Discussion: The study described the prehospital airway management practices by advanced life support providers in South Africa. Rapid sequence intubation had the highest endotracheal intubation success rate overall and the lowest prevalence of adverse events. There was no statistical difference in survival between the rapid sequence intubation, medication facilitated and no-medication group. Due to a lack in standardised treatment guidelines, differences in fluid administration, post-intubation care, confirmation of placement and ventilation were noted. No standard approach to record keeping was found, with the quality of patient care records being variable. A standardised advanced airway management report would be beneficial as it would improve the quality of data recorded and allow for better comparisons to be made

Coding strategies for static patterns suitable for UV deflectometry Codierungsstrategien für in der UV-Deflektometrie anwendbare Muster

Abstract We introduce a method based on the deflectometry principle for the inspection of transparent, rotation-symmetric objects with steep angles. Examples are intraocular or strongly curved, aspheric lenses. Usually, an additional reflection at the lens’ back side occurs and disturbs the signal. The solution is to use ultraviolet light which does not penetrate the material. As a consequence, static masks have to be used to generate the fringe pattern. A key feature of our approach is the specification of a spiral pattern, that meets the requirements for ultraviolet deflectometry with static masks. The spiral patterns are decoded by a multi-frequency phase shifting algorithm. We explain the principles of pattern design and present first evaluation results. Furthermore, we introduce a straight forward approach to obtain the absolute coordinates of the screen directly without any unwrapping. This facilitates the reconstruction of the three-dimensional shape of the lens in a subsequent step

Beyond Personalization: Research Directions in Multistakeholder Recommendation

Recommender systems are personalized information access applications; they are ubiquitous in today's online environment, and effective at finding items that meet user needs and tastes. As the reach of recommender systems has extended, it has become apparent that the single-minded focus on the user common to academic research has obscured other important aspects of recommendation outcomes. Properties such as fairness, balance, profitability, and reciprocity are not captured by typical metrics for recommender system evaluation. The concept of multistakeholder recommendation has emerged as a unifying framework for describing and understanding recommendation settings where the end user is not the sole focus. This article describes the origins of multistakeholder recommendation, and the landscape of system designs. It provides illustrative examples of current research, as well as outlining open questions and research directions for the field.Comment: 64 page

Applying numerical continuation to the parameter dependence of solutions of the Schr\"odinger equation

In molecular reactions at the microscopic level the appearance of resonances has an important influence on the reactivity. It is important to predict when a bound state transitions into a resonance and how these transitions depend on various system parameters such as internuclear distances. The dynamics of such systems are described by the time-independent Schr\"odinger equation and the resonances are modeled by poles of the S-matrix. Using numerical continuation methods and bifurcation theory, techniques which find their roots in the study of dynamical systems, we are able to develop efficient and robust methods to study the transitions of bound states into resonances. By applying Keller's Pseudo-Arclength continuation, we can minimize the numerical complexity of our algorithm. As continuation methods generally assume smooth and well-behaving functions and the S-matrix is neither, special care has been taken to ensure accurate results. We have successfully applied our approach in a number of model problems involving the radial Schr\"odinger equation

Rainfall is associated with social behaviour in Seychelles warblers

Species are facing environmental challenges caused by rapidly changing environments induced by climate change. In tropical regions, climate change causes increasing frequencies of extreme weather,like droughts or extreme rainfall. Natural selection is usually slow and adaptations through phenotypic plasticity are limited, thus species might need more mechanisms to cope with change, like cooperative breeding. Rainfall is an important cue for onset of breeding in many tropical bird species, so young are born when food abundance is highest. We explore the effect of rainfall on the social behaviour and life history of the insectivorous Seychelles warblers (Acrocephalus sechellensis), a facultative cooperative58breeder, using long-term data. We expect that with increasing amounts of rain food resources will increase, and thus reproductive output and survival will increase. If so, in dry periods, reproductive output of breeding pairs will be limited, but cooperative breeding may counteract this negative effect because helpers assist with feeding young. We expect that in dry periods breeding pairs produce more offspring of the helping sex, who stay in their natal territory and become helpers in the following year. Rainfall positively affected insect abundance. With increasing rainfall, survival of individuals during the breeding season and reproductive output, especially for cooperatively breeding groups, increased. With more rainfall, also more daughters (the helping sex) were produced, resulting in more group formation the year after. Thus, in contrast to our expectations, Seychelles warblers form social groups in favourable conditions, indicating that group living may be costly and thus not a solution to coping with changing environments. This study showed that the interaction between the environment and life histories,including social behaviour, is complex, and important to consider when studying the impact of changing environments on species surviva

Rainfall is associated with social behaviour in Seychelles warblers

Species are facing environmental challenges caused by rapidly changing environments induced by climate change. In tropical regions, climate change causes increasing frequencies of extreme weather,like droughts or extreme rainfall. Natural selection is usually slow and adaptations through phenotypic plasticity are limited, thus species might need more mechanisms to cope with change, like cooperative breeding. Rainfall is an important cue for onset of breeding in many tropical bird species, so young are born when food abundance is highest. We explore the effect of rainfall on the social behaviour and life history of the insectivorous Seychelles warblers (Acrocephalus sechellensis), a facultative cooperative58breeder, using long-term data. We expect that with increasing amounts of rain food resources will increase, and thus reproductive output and survival will increase. If so, in dry periods, reproductive output of breeding pairs will be limited, but cooperative breeding may counteract this negative effect because helpers assist with feeding young. We expect that in dry periods breeding pairs produce more offspring of the helping sex, who stay in their natal territory and become helpers in the following year. Rainfall positively affected insect abundance. With increasing rainfall, survival of individuals during the breeding season and reproductive output, especially for cooperatively breeding groups, increased. With more rainfall, also more daughters (the helping sex) were produced, resulting in more group formation the year after. Thus, in contrast to our expectations, Seychelles warblers form social groups in favourable conditions, indicating that group living may be costly and thus not a solution to coping with changing environments. This study showed that the interaction between the environment and life histories,including social behaviour, is complex, and important to consider when studying the impact of changing environments on species surviva

Time-dependent density functional theory: Past, present, and future

Time-dependent density functional theory (TDDFT) is presently enjoying enormous popularity in quantum chemistry, as a useful tool for extracting electronic excited state energies. This article discusses how TDDFT is much broader in scope, and yields predictions for many more properties. We discuss some of the challenges involved in making accurate predictions for these properties.Comment: 12 pages, 4 figure