Minimum Query Set for Decision Tree Construction.

A new two-stage method for the construction of a decision tree is developed. The first stage is based on the definition of a minimum query set, which is the smallest set of attribute-value pairs for which any two objects can be distinguished. To obtain this set, an appropriate linear programming model is proposed. The queries from this set are building blocks of the second stage in which we try to find an optimal decision tree using a genetic algorithm. In a series of experiments, we show that for some databases, our approach should be considered as an alternative method to classical ones (CART, C4.5) and other heuristic approaches in terms of classification quality.

A randomized crossover comparison of the bébé VieScope and direct laryngoscope for pediatric airway management by nurses in medical simulation settings.

BACKGROUND: Airway management in life-threatening emergencies is essential for children, and endotracheal intubation is the gold standard. It protects against regurgitation and enables mechanical ventilation. New types of airway management equipment are being developed and implemented to meet the needs of medical personnel. RESEARCH DESIGN AND METHODS: This prospective, randomized, cross-over simulation trial evaluated the success of endotracheal intubation in three scenarios: normal airway (scenario-A), tongue edema (scenario-B), and continuous chest compression (scenario-C), using the bébé Vie Scope™ laryngoscope (VieScope) and the Macintosh blade laryngoscope (MAC) as a comparative tool performed by nurses with limited tracheal intubation experience. RESULTS: The results of the study showed that in scenario-A, there were no significant differences in the first attempt success rate or endotracheal intubation time between VieScope and MAC. However, VieScope was associated with better visualization of the glottis. In scenarios B and C, VieScope was significantly more effective than MAC in terms of first-pass success rate, time to intubate, Cormack-Lehane grade, POGO score, and ease of endotracheal intubation. CONCLUSIONS: Bébé VieScope may be useful for endotracheal intubation in pediatric patients, particularly in cases of tongue edema and ongoing chest compression, providing a higher first-pass success rate than conventional laryngoscopes.

ETView SL versus Macintosh Direct Laryngoscope for Endotracheal Intubation Amid Simulated COVID-19 Cardiac Arrest: A Randomized Crossover Study.

Airway management procedures, such as endotracheal intubation (ETI), pose a significant risk of aerosol generation, requiring robust personal protective equipment (PPE) against aerosol-generating procedures (AGP). This study aimed to assess the impact of PPE-AGP on intubation success rates, time to intubation, and glottic visualization using ETView and a standard Macintosh laryngoscope (MAC). A total of 52 physicians participated in this prospective, observational, randomized crossover study conducted in a medical simulation setting. Participants included COVID-19 patients with cardiac arrest scenarios with and without PPE-AGP who were intubated with ETView and MAC. During intubation without PPE-AGP, ETView showed a similar first-pass success rate (FPS) but had a shorter intubation time and better glottal hydration compared to MAC. In scenario B (with PPE-AGP), ETView outperformed MAC in FPS, initiation time, and glottic visualization. The use of PPE-AGP had little impact on ETView's performance. However, it negatively affected the Macintosh laryngoscope, reducing FPS and glottic visibility. Participants found intubation with ETView easier in both scenarios. In conclusion, as compared to the Macintosh laryngoscope, ETView demonstrated higher performance under the circumstances of the simulation, especially when PPE-AGP was used.

Impact of VieScope® on first-attempt success during simulated COVID-19 patients intubation: A randomized cross-over simulation trial.

BACKGROUND: The purpose of our study was to determine the efficacy of intubation with VieScope® and Macintosh laryngoscope in different scenarios of simulated COVID-19 patients by paramedics wearing personal protective equipment (PPE) for aerosol gener-ating procedures (AGPs). METHODS: Study was designed as a prospective, observational, randomized, crossover simulation trial. 37 paramedics took part in the study. They performed endotracheal intubation (ETI) of a person suspected of COVID-19. Intubation was performed using VieS-cope® and Macintosh laryngoscopes in two research scenarios: Scenario A - normal airway and Scenario B - difficult airway. Both the order of participants and the methods of intubation were random. RESULTS: In Scenario A, time to intubation using VieScope® and Macintosh laryngoscope amounted to 35.3 (IQR; 32-40) seconds and 35.8 (IQR: 30-40)s, respectively. Nearly all participants performed ETI successfully both with VieScope® and Macintosh laryngo-scope (100% vs. 94.6%). In scenario B, intubation with the VieScope®, compared to the Macintosh laryngoscope, was associated with a shorter intubation time (p<0.001), a higher success rate of the first intubation attempt (p<0.001), a better visualization degree glottis (p=0.012) and ease of intubation (p<0.001). CONCLUSION: Our analysis suggests that the use of a VieScope® compared to Macintosh laryngoscope in difficult airway intuba-tion performed by paramedics wearing PPE-AGP is associated with shorter intubation times, greater intubation efficiency as well as better visualization of the glottis. Additional clinical trials are necessary to confirm the obtained results.

Temperature and E-Poling Evolution of Structural, Vibrational, Dielectric, and Ferroelectric Properties of Ba1-xSrxTiO3 Ceramics (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.45).

Lead-free Ba1-xSrxTiO3 (BST) (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.45) ceramics were successfully prepared via the solid-state reaction route. A pure perovskite crystalline structure was identified for all compositions by X-ray diffraction analysis. The basic phase transition temperatures in these ceramics were studied over a wide temperature range. A change in symmetry from a tetragonal to cubic phase was detected, which was further proven by phonon anomalies in composition/temperature-dependent Raman spectra. The incorporation of Sr2+ into BaTiO3 (BT) lead to a shift in the phase transitions to lower temperatures, suppressing the ferroelectric properties and inducing relaxor-like behavior. Therefore, it was reasonable to suppose that the materials progressively lack long-range ordering. The initial second-harmonic generation (SHG) measurements demonstrated that the cubic phase of BST ceramics is not purely centrosymmetric over a wide temperature interval. We discussed the possible origin of the observed effects, and showed that electric field poling seems to reconstruct the structural ordering destroyed by the introduction of Sr2+ to BT. In the first approximation, substitution of Sr for larger Ba simply reduced the space for the off-central shift in Ti in the lattice and hence the domain polarization. A-site cation ordering in BST and its influence on the density of electronic states were also explored. The effect of doping with strontium ions in the BST compound on the density of electronic states was investigated using ab initio methods. As the calculations showed, doping BT with Sr2+ atoms led to an increase in the bandgap. The proposed calculations will also be used in the subsequent search for materials optimal for applications in photovoltaics.

Ceramic Matrix Composites Obtained by the Reactive Sintering of Boron Carbide with Intermetallic Compounds from the Ti-Si System.

In this study, we investigated the effect of adding two different intermetallics, Ti5Si3 and TiSi2, for the preparation of TiB2-SiC-B4C composites. As part of the research, stoichiometric composites consisting only of two phases TiB2 and SiC were obtained. The TiB2-SiC-B4C composites were prepared via pressureless sintering. The presence of the phases in the sintered composites was confirmed using X-ray diffraction and scanning electron microscopy. The SEM-EDS examination revealed that the TiB2 and SiC phases were formed during the composite process synthesis and were distributed homogeneously in the B4C matrix. The obtained results allowed us to usually exceed 2000 °C and the use of specialized equipment for firing, that is, vacuum or protective atmosphere furnaces as well as control and measurement equipment. Such an approach generates high costs that are decisive for the economics of the technological processes. In the case of our compositions, it is possible to lower the temperature to 1650 °C. The TiB2-SiC-B4C composites were classified as UHTCs.

Efficacy of Targeted Temperature Management after Pediatric Cardiac Arrest: A Meta-Analysis of 2002 Patients.

Cardiac arrest (CA) is associated with high mortality and poor life quality. Targeted temperature management (TTM) or therapeutic hypothermia is a therapy increasing the survival of adult patients after CA. The study aim was to assess the feasibility of therapeutic hypothermia after pediatric CA. We performed a systematic review and meta-analysis of randomized controlled trials and observational studies evaluating the use of TTM after pediatric CA. The primary outcome was survival to hospital discharge or 30-day survival. Secondary outcomes included a one-year survival rate, survival with a Vineland adaptive behavior scale (VABS-II) score ≥ 70, and occurrence of adverse events. Ten articles (n = 2002 patients) were included, comparing TTM patients (n = 638) with controls (n = 1364). In a fixed-effects meta-analysis, survival to hospital discharge in the TTM group was 49.7%, which was higher than in the non-TTM group (43.5%; odds ratio, OR = 1.22; 95% confidence interval, CI: 1.00, 1.50; p = 0.06). There were no differences in the one-year survival rate or the occurrence of adverse events between the TTM and non-TTM groups. Altogether, the use of TTM was associated with a higher survival to hospital discharge; however, it did not significantly increase the annual survival. Additional high-quality prospective studies are necessary to confer additional TTM benefits.