Correct Depth Research Articles

Binocular dynamic holographic three-dimensional display for optical see-through augmented reality using two spatial light modulators

In this paper, a binocular see-through holographic three-dimensional (3D) display system based on two spatial light modulators (SLMs) is proposed and implemented, where the SLMs are used to load the phase-only holograms of the left and right 3D perspective images of a volumetric scene for optical holographic reconstruction with correct depth cues, respectively. Moreover, two beam splitters are employed to achieve the functions of directional light-guide devices and optical combiners simultaneously for providing binocular augmented reality (AR) sensation. Optical experiments demonstrate that the proposed system can successfully present binocular holographic AR 3D images with both binocular parallax and accommodation effect, which enables observation free of the accommodation-vergence conflict and visual fatigue problem. Furthermore, the capability of dynamic display with the proposed system is also tested in the experiments by synchronously refreshing the SLMs with the sequential holograms, and the captured videos demonstrate that the proposed system shows a promising potential for the real-time binocular AR true 3D display products.

Verbal Motivation vs. Digital Real-Time Feedback during Cardiopulmonary Resuscitation: Comparing Bystander CPR Quality in a Randomized and Controlled Manikin Study of Simulated Cardiac Arrest

Objective The use of smartphone applications increases bystander CPR quality as well as the use of telephone CPR protocols. The present prospective, randomized, controlled manikin trial analyses the effects of a smartphone application (PocketCPR©) on CPR quality in a bystander CPR scenario compared to a dispatcher-assisted telephone CPR with the additional use of a metronome and verbal motivation. Methods: 150 laypersons were included to perform 8-minute CPR on a manikin. Volunteers were randomly assigned to one of three groups: (1) dispatcher-assisted telephone CPR (telephone-group), (2) dispatcher-assisted telephone CPR combined with the smartphone-application (telephone + app-group) and (3) dispatcher-assisted telephone CPR with additional verbal motivation (“push harder, release completely,” every 20 seconds, starting after 60 seconds) and a metronome with 100 min−1 (telephone + motivation-group). Results: Median compression depth did not differ significantly between the study groups (p = 0.051). However, in the post hoc analysis median compression depth in the telephone + motivation-group was significantly elevated compared to the telephone + app-group (59 mm [IQR 47–67 mm] vs. 51 mm [IQR 46–57 mm]; p = 0.025). The median number of superficial compressions was significantly reduced in the telephone + motivation-group compared to the telephone + app-group (70 [IQR 3–362] vs. 349 [IQR 88–538]; p = 0.004), but not compared to the telephone-group (91 [IQR 4–449]; p = 0.707). In contrast to the other study groups, median compression depth of the telephone + motivation-group increased over time. Chest compressions with correct depth were found significantly more often in the telephone + app-group compared to the other study groups (p = 0.011). Median compression rate in the telephone + app-group was significantly elevated (108 min−1 [IQR 96–119 min−1]) compared to the telephone-group (78 min−1 [IQR 56–106 min−1]; p < 0.001) and the telephone + motivation-group (99 min−1 [IQR 91–101 min−1]; p < 0.001). Conclusions: The use of a smartphone application as well as verbal motivation by a dispatcher during telephone CPR leads to higher CPR quality levels compared to standard telephone CPR. Thereby, the use of the smartphone application mainly shows an increase in compression rate, while increased compression rate with simultaneously increased compression depth was only apparent in the telephone + motivation-group.

The use of prefilled adrenaline syringes improves cardiopulmonary resuscitation quality-high-fidelity simulator-based study.

BackgroundIn some countries, adrenaline is available only in glass ampoules. However, simplification of cardiopulmonary resuscitation (CPR) by introducing prefilled syringes may ensure more efficient CPR. The aim of this study was to investigate the impact of different forms of adrenaline on the CPR quality.MethodsIn a randomized cross-examination simulation study, 100 two-person paramedical teams took part in two 10-minute scenarios of sudden cardiac arrest (SCA) in a pulseless electrical activity mechanism (PEA). In the first scenario the set of medicines contained glass ampoules (group ST) with adrenaline, in the second prefilled syringes (group AMPS). The parameters of the CPR quality [correct number and depth of chest compressions (CC), no flow time, chest recoil, time to apply supraglottic airways device (SAD)] were compared.ResultsIn group AMPS the first dose of adrenaline was administered after 114.2±28.3 seconds after the initiation of CPR whereas after 178.1±62.6 seconds in group ST (P<0.001). Chest compression fraction (CCF) was higher (81.8%±6.1%) in group AMPS than in group ST (71.2%±7.5%). Paramedics performed CC at better frequency, to a preferred depth and in an appropriate place in group AMPS. Faster decision to apply SAD (131.7±34.0 s in group AMPS and 220.3±81.5 s in group ST) ensured faster achievement of airway patency in this group (181.5±48.7 vs. 271.2±101.5 s).ConclusionsPrefilled syringes with crucial drugs during CPR may significantly improve the quality of CPR performed by two-person teams.

Autoconfianza, conocimiento y habilidades de los practicantes de enfermería con respecto a la reanimación cardiopulmonar

Introducción: El paro cardiorrespiratorio es una condición de salud crítica, cuya tasa de supervivencia está asociada a la velocidad con la que se realiza la reanimación cardiopulmonar. Objetivo: Evaluar la autoconfianza, el conocimiento y las habilidades de reanimación cardiopulmonar de los practicantes de enfermería. Materiales y métodos: Se trata de un estudio descriptivo de enfoque cuantitativo que fue realizado de abril a julio de 2018 en una universidad pública del noreste de Brasil con 80 practicantes de enfermería. Se realizó un examen de conocimiento, escala de autoconfianza en situaciones de emergencia y evaluación práctica de las habilidades con el uso de un maniquí. Se utilizaron las pruebas de Kruskal-Wallis y Chi-cuadrado de Pearson. Resultados: Los practicantes mostraron tener poca confianza en sí mismos ante una emergencia. Las preguntas teóricas sobre la ubicación para verificar el pulso y la posición de la víctima fueron las que más acertaron los practicantes. Los principales vacíos de conocimiento estaban relacionados con el inicio de las compresiones (p = 0.245) y el número de compresiones/respiraciones (p = 0.034). En términos de habilidades, los vacíos estaban relacionados con la posición de las manos y brazos del rescatador (p = 0.058), el movimiento del tronco (p = 0.062) y la profundidad correcta de las compresiones (p = 0.086). Discusión: Es necesario impartir capacitación periódica y formación continua para una atención rápida, segura y efectiva de parte de los futuros enfermeros. Conclusión: Se evidenciaron insuficiencias en los conocimientos y aptitudes, lo que pone de relieve la importancia de las nuevas metodologías para intensificar y garantizar la efectividad del proceso de enseñanza-aprendizaje. Como citar este articulo: Brandão, Maria Girlane Sousa Albuquerque; Fontenele, Natália Ângela Oliveira; Ximenes, Maria Aline Moreira; Lima, Magda Milleyde de Sousa; Neto, Nelson Miguel Galindo; Araújo, Thiago Moura; Barros, Lívia Moreira. Autoconfiança, conhecimento e habilidade acerca da ressuscitação cardiopulmonar de internos de enfermagem. Revista Cuidarte. 2020; 11(2): e982. http://dx.doi.org/10.15649/cuidarte.982

Analysis of the quality of chest compressions during resuscitation in an understaffed team — randomised crossover manikin study

INTRODUCTION: According to the chain of survival, chest compressions (CCs) are crucial in every cardiac arrest patient. It is very challenging to provide high-quality resuscitation in a two-paramedic team. The task of an automatic chest compression device (ACCD) is to relieve the rescuer and improve the quality of CCs. Its influence on the quality of the whole resuscitation as well as the survival of patients is still subject to discussion worldwide. This study aimed to assess the quality of CCs during resuscitation in a two-paramedic team using ACCD. MATERIAL AND METHODS: This research was designed as a prospective, randomised, cross-over, high-fidelity simulation study. Fifty-two double paramedic teams took part in the research. The role of the participants was to conduct full advanced resuscitation in a human patient’s simulator. Each team provided resuscitation twice. Once with an ACCD and once using manual compressions. Chest compression quality parameters, as well as chest compression fraction (CCF), were measured. RESULTS : Statistically significant differences were found between manual and automated compressions in: mean depth (48 ± 4 mm vs. 56 ± 3 mm, p < 0.0001), mean rate (117 ± 9 mm vs. 103 ± 1 mm, p < 0.0001), percentage of CC with correct depth (46 ± 25 vs. 87 ± 13, p < 0.0001), rate (72 ± 22 vs. 96 ± 4, p < 0.0001), and recoil (55 ± 23 vs. 89 ± 13, p < 0.0001). CCF was also higher when the ACCD was used (74 ± 7% vs. 83 ± 2%, p < 0.0001). CONCLUSIONS: The use of an ACCD increases the quality of compressions by improving CCF, chest recoil, and the percentage of compressions performed with adherence to guidelines.

A Fast Analysis Method for Blue-Green Laser Transmission through the Sea Surface.

The fast estimation of blue-green laser transmission characteristics through the fluctuating sea surface, such as refraction angles and transmittance, is very important to correct operating parameters, detection depth and anti-detection warning in airborne Light Detection and Ranging (LiDAR) applications. However, the geometry of the sea surface is changed by complex environment factors, such as wind and wave, which significantly affect the rapid acquisition of the blue-green laser transmission characteristics. To address this problem, a fast analysis method is provided to rapidly compute the blue-green laser transmittance and refraction angles through the fluctuating sea surface driven by different wind directions and speeds. In the method, a three-dimensional wave model driven by the wind was built to describe the wave spatial distribution varying with time. Using the wave model, the propagation path of the scanning laser footprint was analyzed using the proposed meshing method, thus the transmittance and refraction angles of the optical path can be fast obtained by using parallel computing. The simulation results imply that the proposed method can reduce the time consumption by 70% compared with the traditional analytical method with sequential computing. This paper provides some statistical laws of refraction angles and transmittance through the fluctuating sea surface under different wind conditions, which may serve as a basic for fast computation of airborne LiDAR transmission characteristics in complex environments.

Evaluation Of CPR Quality Via Smartphone With A Video Livestream – A Study In A Metropolitan Area

Background Telephone-assisted cardiopulmonary resuscitation (CPR) is an effective and proven tool to improve patient survival and outcome after cardiac arrest, and is therefore recommended in international resuscitation guidelines. A new technology that provides the emergency medical services (EMS) dispatcher with a video livestream from a smartphone during telephone-assisted CPR was investigated to assess whether a correct judgment of CPR quality is feasible. Material and Methods After Ethics Committee approval, we conducted this study from August to September 2018 in the University Hospital of Cologne and its metropolitan area. Our study team set up a full-scale resuscitation mannequin on 54 study sites. Video telephony between caller and EMS dispatcher was established, and CPR was initiated with randomized common quality issues concerning compression frequency, compression depth, and compression point. It was evaluated whether the dispatcher recognized correct and incorrect resuscitation performance. Results Forty-six video calls were established successfully. EMS dispatching staff identified correct compression frequency (100-120/min) in 87.5% of the cases, too low frequency (<80/min) was correctly identified in 92%, and too high frequency (>140/min) in 58.5%, respectively. Correct compression depth (5-6 cm) was identified in 70.6%, shallow compressions (<3cm) in 92.9% and a continuous decrease of depth in 100% of all cases. Correct compression point was identified in 87.5%, incorrect epigastric compression in 92.3%, incomplete release in 58.8%. Conclusion A video livestream from a smartphone can support an EMS dispatcher’s assistance in resuscitation. Typical resuscitation mistakes, like incorrect compression frequency or depth, and incorrect compression points could be recognized and corrected efficiently via video livestream.

Quantification of Passive Ventilation Produced by Manual Chest Compressions Using a New Cardiopulmonary Resuscitation Feedback Device

AbstractSeveral studies have shown that chest compressions (CC) alone may produce in addition to blood circulation, a short-term passive ventilation. However, it is not clear whether high CC quality may produce in even greater amount of ventilation volumes. The aim of this study was to evaluate whether CC, using a new feedback device, can produce a substantial and sustainable passive volumes compared to standard CC. Thirty inexperienced volunteers performed CC for 2 min on a developed thoracic lung model and using a new feedback device. Participants were randomized into two groups that performed either CC with feedback first, followed by a trial without feedback, or vice versa. Efficient compression rate (correct CC rate and depth simultaneously) was significantly higher in feedback session (43.6% versus 25.5%; P = 0.006). As well, CC rate and depth efficiency were improved with feedback. Moreover, average tidal volumes and minute volumes that occurred during CC alone were significantly improved in feedback session (79.8 ± 5 ml versus 72.9 ± 7 ml) and (8.8 l/min versus 7.9 l/min), respectively (P &amp;lt; 0.001). Yet, no significant difference was found between the first and the 90th second interval (9.04 l/min versus 8.68 l/min, P = 0.163) in the feedback session. Conversely, a significant difference was evident after the first 15th seconds interval without feedback (8.77 l/min initially versus 8.38 l/min; P = 0.041). This study revealed that the new CPR feedback device improved CC quality in inexperienced volunteers. As well, the passive ventilation volumes were significantly increased and sustained when the device was used.

Comparing Real-Time Feedback Modalities to Support Optimal Cardiopulmonary Resuscitation for Undergraduate Nursing Students: A Quasi-Experimental Cross-Over Simulation Study

BackgroundOptimal cardiopulmonary resuscitation (CPR) is reliant on a chain of well performed interventions and skills. To investigate whether CPR feedback devices improve performance for nursing students, the effects of three feedback modalities—visual: Laerdal SimPad®; visual-embodied metaphoric: Innosonian Brayden Pro®; and visual-audio: Physio-Control TrueCPR®—was tested. MethodA quasi-experimental cross-over study compared performance metrics of participant exposure to three feedback modalities and standard adult basic life support (BLS) without feedback in a simulated environment. After baseline training, 64 participants performed adult single-rescuer BLS on a manikin for each modality and without feedback for two minutes. Effective chest compressions (correct depth, thoracic recoil, pressure point, rate, no-flow fraction) and ventilation parameters were compared using Friedman and Wilcoxon tests. ResultsSuperior technical accuracy in CPR skills performance was evident with all feedback modalities when compared with no feedback p = <.05); visual-audio feedback (TrueCPR®) was most effective (p = .005). Participants demonstrated higher technical accuracy in CPR performance (30:2 cycles; chest compression number/rate/depth; chest recoil; pressure point; correct number of ventilations) when compared with no feedback (p = .0001), despite achieving national certification three weeks before data collection. ConclusionThis appears to be the first study to explore the use of feedback modalities during CPR performance in nursing students. These feedback devices can play a major role in improving measurable parameters of BLS and psychomotor skill capability. Modalities varied in their ability to improve performance; visual-audio feedback significantly improved chest compressions, ventilation and cycle performance, whereas visual-graph–based feedback improved flow fraction and ventilations.

Point-of-Care Ultrasound in Sternal Notch Confirms Depth of Endotracheal Tube in Children.

To determine if a saline-filled cuff seen at the suprasternal notch on ultrasound corresponds to correct endotracheal tube depth on a chest radiograph (tip at/below clavicle AND ≥ 1 cm above carina). Prospective observational study. Tertiary Care Pediatric hospital. Patients between the ages of 0-18 years requiring nonemergent cardiac catheterizations and endotracheal intubation with a cuffed endotracheal tube were included in the study. Children with anticipated or known difficult airways were excluded. Ultrasound evaluation of the neck following saline inflation of the endotracheal tube cuff. Ultrasonography of the patient's neck was performed following intubation by a pediatric anesthesiologist. A linear probe was used in transverse axis to identify the saline-filled cuff starting at the suprasternal notch and moving cephalad. A cine-fluoroscopic image, similar to a chest radiograph, was obtained to ascertain the endotracheal tube depth after the cuff was identified sonographically. Endotracheal tube cuffs seen on ultrasound at the suprasternal notch were compared with the endotracheal tube depth on the cine-fluoroscopic image. A total of 75 children were enrolled in the study. The endotracheal tube was seen sonographically at the suprasternal notch in 70 patients of which 60 had complete data (an adequate chest radiograph available for review). Patient ages ranged from 2 months to 18 years with a median age of 4 years. The median endotracheal tube tip to carina distance was 2.4 cm (interquartile range, 1.75-3.3 cm.) The endotracheal tube tip to carina distance was greater than or equal to 1 cm in 57 out of the 60 patients. Endotracheal tube cuff at the suprasternal notch on ultrasound corresponded with correct endotracheal tube depth on chest radiograph with an accuracy of 95% (CI, 86-98%). Visualization of the cuff at the suprasternal notch by ultrasound demonstrates potential as a means of confirming correct depth of the endotracheal tube following endotracheal intubation.

Rescue under ongoing CPR from an upper floor: evaluation of three different evacuation routes and mechanical and manual chest compressions: a manikin trial

BackgroundIf transport under ongoing cardiopulmonary resuscitation (CPR) from an upper floor is indicated, the ideal CPR-method and evacuation route is unknown hitherto. We aimed to elaborate a strategy for evacuation of patients under ongoing CPR from an upper floor, comparing three different evacuation routes and manual and mechanical chest compressions.MethodsA CPR-training manikin recording CPR-quality was placed on the fifth floor and was evacuated to an ambulance via lift, turntable ladder, or staircase. Chest compressions were performed manually or with a mechanical CPR-device. Efficiency endpoints were compression depth and frequency, sufficiency of chest release, compared with European Resuscitation Council (ERC) Guidelines, and duration of the evacuation. Adverse outcomes were disconnection/dislocation of devices and hazards/accidents to the personnel.ResultsFor all evacuation routes, compression depth and frequency were significantly more compliant with ERC-guidelines under mechanical CPR. Manual CPR was associated with considerable deviations from correct compression depth and frequency. Chest release only slightly differed between groups. Evacuation via lift under mechanical CPR was fastest and evacuation via turntable ladder under manual CPR was slowest. No device disconnections or accidents occurred, but hazard to personnel was perceived during evacuation via ladder under manual CPR.ConclusionsIn this study, a mechanical CPR-device proved to deliver better CPR-quality during evacuation from an upper floor. If a lift accessible with a stretcher is available, this route should be preferred, regardless of manual or mechanical CPR. Turntable ladders can only be meaningfully used with mechanical CPR, otherwise CPR-quality is poor and hazard to the personnel is increased. Not all evacuation routes may be useable in a specific real-life scenario.Trial registrationGerman Clinical Trials Registry, www.drks.de, registration number DRKS00012885, registration date 17.08.2017.

Investigation on spatial distribution of acoustic resonance in annular cavity: Frequency and intensity

This paper studies the acoustic behavior inside the deep annular and cylindrical cavity at low Mach number. The turbulent shear layer above the cavity acts as a broadband noise source and drives resonant standing waves inside the cavity for various modes. According to previous investigation, those resonant standing waves inside the cavity play an important role in the aeroacoustic resonance of cavity noise, which gives perfect prediction of tonal frequency from the solution of wave equation. From the perspective of engineering application, it is more important to predict the spatial distribution of tonal intensity. It is needed to point out that the solution of the linear wave equation also provides the relative spatial distribution tonal intensity and the absolute value of tonal intensity can be determined from the acoustic experiments that is measured only at some locations. Based on this idea, a scheme is setup and validated to predict the amplitude spatial distribution of tonal intensity of aeroacoustic resonance. For example, an analytical model is established to provide the relative mode shape of aeroacoustic resonance in a simple geometry of cavity, which is realized by solving the wave equation with boundary conditions in a semi-closed space. This model considers the freestream velocity scaling and the depth correction factor varying with the Helmholtz number. The experimental aeroacoustic result is acquired by measuring the pressure fluctuation at some locations of cavity internal wall with the use of surface microphones. The experimental results are used to supplement and validate this analytical model. The amplitude spatial distribution at any freestream velocity (low Mach number) can be acquired by measuring the pressure fluctuation once at the leading edge or trailing edge of cavity bottom at an arbitrary Mach number, as the amplitude of most modes reaches its maximum here.

Design of an end-effector for robot-assisted ultrasound-guided breast biopsies

PurposeThe biopsy procedure is an important phase in breast cancer diagnosis. Accurate breast imaging and precise needle placement are crucial in lesion targeting. This paper presents an end-effector (EE) for robotic 3D ultrasound (US) breast acquisitions and US-guided breast biopsies. The EE mechanically guides the needle to a specified target within the US plane. The needle is controlled in all degrees of freedom (DOFs) except for the direction of insertion, which is controlled by the radiologist. It determines the correct needle depth and stops the needle accordingly.MethodIn the envisioned procedure, a robotic arm performs localization of the breast, 3D US volume acquisition and reconstruction, target identification and needle guidance. Therefore, the EE is equipped with a stereo camera setup, a picobeamer, US probe holder, a three-DOF needle guide and a needle stop. The design was realized by prototyping techniques. Experiments were performed to determine needle placement accuracy in-air. The EE was placed on a seven-DOF robotic manipulator to determine the biopsy accuracy on a cuboid phantom.ResultsNeedle placement accuracy was 0.3 ± 1.5 mm in and 0.1 ± 0.36 mm out of the US plane. Needle depth was regulated with an accuracy of 100 µm (maximum error 0.89 mm). The maximum holding force of the stop was approximately 6 N. The system reached a Euclidean distance error of 3.21 mm between the needle tip and the target and a normal distance of 3.03 mm between the needle trajectory and the target.ConclusionAn all in one solution was presented which, attached to a robotic arm, assists the radiologist in breast cancer imaging and biopsy. It has a high needle placement accuracy, yet the radiologist is in control like in the conventional procedure.

Virtual View Synthesis Based on Asymmetric Bidirectional DIBR for 3D Video and Free Viewpoint Video

Depth image-based rendering (DIBR) plays an important role in 3D video and free viewpoint video synthesis. However, artifacts might occur in the synthesized view due to viewpoint changes and stereo depth estimation errors. Holes are usually out-of-field regions and disocclusions, and filling them appropriately becomes a challenge. In this paper, a virtual view synthesis approach based on asymmetric bidirectional DIBR is proposed. A depth image preprocessing method is applied to detect and correct unreliable depth values around the foreground edges. For the primary view, all pixels are warped to the virtual view by the modified DIBR method. For the auxiliary view, only the selected regions are warped, which contain the contents that are not visible in the primary view. This approach reduces the computational cost and prevents irrelevant foreground pixels from being warped to the holes. During the merging process, a color correction approach is introduced to make the result appear more natural. In addition, a depth-guided inpainting method is proposed to handle the remaining holes in the merged image. Experimental results show that, compared with bidirectional DIBR, the proposed rendering method can reduce about 37% rendering time and achieve 97% hole reduction. In terms of visual quality and objective evaluation, our approach performs better than the previous methods.

The HI/OH/Recombination line survey of the inner Milky Way (THOR): data release 2 and H I overview

Context.The Galactic plane has been observed extensively by a large number of Galactic plane surveys from infrared to radio wavelengths at an angular resolution below 40′′. However, a 21 cm line and continuum survey with comparable spatial resolution is lacking.Aims.The first half of THOR data (l= 14.0°−37.9°, andl= 47.1°−51.2°, |b|≤ 1.25°) has been published in our data release 1 paper. With this data release 2 paper, we publish all the remaining spectral line data and Stokes I continuum data with high angular resolution (10′′–40′′), including a new H Idataset for the whole THOR survey region (l= 14.0−67.4° and |b|≤ 1.25°). As we published the results of OH lines and continuum emission elsewhere, we concentrate on the H Ianalysis in this paper.Methods.With theKarl G. JanskyVery Large Array (VLA) in C-configuration, we observed a large portion of the first Galactic quadrant, achieving an angular resolution of ≤40′′. AtLBand, the WIDAR correlator at the VLA was set to cover the 21 cm H Iline, four OH transitions, a series of Hnαradio recombination lines (RRLs;n= 151 to 186), and eight 128 MHz-wide continuum spectral windows, simultaneously.Results.We publish all OH and RRL data from the C-configuration observations, and a new H Idataset combining VLA C+D+GBT (VLA D-configuration and GBT data are from the VLA Galactic Plane Survey) for the whole survey. The H Iemission shows clear filamentary substructures at negative velocities with low velocity crowding. The emission at positive velocities is more smeared-out, likely due to higher spatial and velocity crowding of structures at the positive velocities. Compared to the spiral arm model of the Milky Way, the atomic gas follows the Sagittarius and Perseus Arm well, but with significant material in the inter-arm regions. With the C-configuration-only H I+continuum data, we produce an H Ioptical depth map of the THOR areal coverage from 228 absorption spectra with the nearest-neighbor method. With thisτmap, we corrected the H Iemission for optical depth, and the derived column density is 38% higher than the column density with optically thin assumption. The total H Imass with optical depth correction in the survey region is 4.7 × 108 M⊙, 31% more than the mass derived assuming the emission is optically thin. If we applied this 31% correction to the whole Milky Way, the total atomic gas mass would be 9.4–10.5 × 109 M⊙. Comparing the H Iwith existing CO data, we find a significant increase in the atomic-to-molecular gas ratio from the spiral arms to the inter-arm regions.Conclusions.The high-sensitivity and resolution THOR H Idataset provides an important new window on the physical and kinematic properties of gas in the inner Galaxy. Although the optical depth we derive is a lower limit, our study shows that the optical depth correction issignificant for H Icolumn density and mass estimation. Together with the OH, RRL and continuum emission from the THOR survey, these new H Idata provide the basis for high-angular-resolution studies of the interstellar medium in different phases.

The effect of chest compression frequency on the quality of resuscitation by lifeguards. A prospective randomized crossover multicenter simulation trial.

The ability to perform high-quality cardiopulmonary resuscitation is one of the basic skills for lifeguards. The aim of the study was to assess the influence of chest compression frequency on the quality of the parameters of chest compressions performed by lifeguards. This prospective observational, randomized, crossover simulation study was performed with 40 lifeguards working in Warsaw, Wroclaw, and Poznan, Poland. The subjects then participated in a target study, in which they were asked to perform 2-min cycles of metronome-guided chest compressions at different rates: 80, 90, 100, 110, 120, 130, 140, and 150 compressions per minute (CPM). The study involved 40 lifeguards. Optimal chest compression score calculated by manikin software was achieved for 110-120 CPM. Chest compression depth achieved 53 (interquartile range [IQR] 52-54) mm, 56 (IQR 54-57) mm, 52.5 (IQR 50-54) mm, 53 (IQR 52-53) mm, 50 (IQR 49-51) mm, 47 (IQR 44-51) mm, 41 (IQR 40-42) mm, 38 (IQR 38-43) mm for 80, 90, 100, 110, 120, 130, 140 and 150 CPM, respectively. The percentage of chest compressions with the correct depth was lower for rates exceeding 120 CPM. The rate of 100-120 CPM, as recommended by international guidelines, is the optimal chest compression rate for cardiopulmonary resuscitation performed by lifeguards. A rate above 120 CPM was associated with a dramatic decrease in chest compression depth and overall chest compression quality. The role of full chest recoil should be emphasized in basic life support training.

Combining Low-Cost Sonar and High-Precision Global Navigation Satellite System for Shallow Water Bathymetry

Periodic bathymetry surveys are essential to provide data to keep navigation charts updated, obtain insights into water body bottom dynamics and processes, and for hydrodynamic modelling. Frequent bathymetry monitoring has become particularly important in a time of climate variability, which may affect hydrodynamics in yet unknown ways. Bathymetric data are, however, often scarce, because surveys are generally time consuming, expensive and complicated. A methodology combining a low-cost single beam sonar with a dual-frequency differential high-precision GNSS (Global Navigation Satellite System) is presented. Sonar depth measurements and GNSS positions were integrated optimizing sonar and GNSS track overlay. As a result, no physical, electronic link between both devices is needed, and precise positions and depths can be obtained without the need to apply the approach based on tide correction, which always introduces some uncertainty. The methodology was successfully tested and validated, with data collected inside an estuary and offshore the estuarine inlet. Vertical accuracies, assessed at track crossings and on locations of known depths, showed mean squared errors of about 20 cm, suggesting that the method is reliable in providing bathymetric data that satisfy the highest standards of the IHO for hydrographic surveys. Validation results suggest that the effects of boat pitch, roll and yaw on depth measurements were negligible in our survey, which covered depths between 0.4 and 24.5 m below MSL and were carried out in quite calm waters, though larger errors occurred in the off-shore zone. The use of an inertial measurement unit (IMU), which can easily be coupled with the GNSS to extract ship motion data and correct depths accordingly, is advised for less optimal survey conditions and deeper waters. The proposed method is accurate, simple and affordable, allowing for more frequent surveys and a better coverage of dynamic shallow water systems such as rivers and estuaries.

Evaluation of Public Awareness, Knowledge and Attitudes about Cardiopulmonary Resuscitation: Report of İzmir.

Early initiation of cardiopulmonary resuscitation (CPR) by witnesses increases survival after cardiac arrest. In Turkey, our country, it is rare that basic life support (BLS) is initiated by a layperson. In our study, we aimed to use a survey to research awareness, level of knowledge and attitudes of the public to CPR and BLS. A 21-question survey was administered to individuals aged ≥18 years on a busy street in a city of a western region of Turkey. Topics such as knowledge about cardiac arrest findings, previous experience of CPR, knowledge of BLS and concerns related to CPR were questioned. The fully completed forms of 533 people were evaluated. There were 40.7% who stated that they had received training in CPR. For signs of cardiac arrest, 40.7% answered loss of consciousness, 49.3% answered cessation of breathing and 60.7% answered cessation of circulation. It was found that 35.5% could perform only chest compressions, 27.6% could perform mouth-to-mouth ventilation and 28.7% able to perform both. While 52.0% knew the location for performing chest compressions, 34.3% knew the correct depth and 15.6% knew the correct compression-ventilation rate. Bystander CPR was performed by 3.6%. In conclusion, 40.7% of people living in a highly educated region in the western part of Turkey had received CPR training and 3.6% performed bystander CPR. A majority of participants stated that they were willing to correct and develop their knowledge and skills related to CPR. Effective public CPR training programmes may increase the knowledge and awareness of CPR in the adult population.

Depth corrections to surface-wave magnitudes for intermediate and deep earthquakes in the regions of North Eurasia

This paper reports a study of surface wave MS,MOS magnitudes from the seismological catalog derived from teleseismic stations of the Geophysical Survey of the Russian Academy of Sciences (GS RAS) with aim of determination of depth corrections to MS and subsequent standardization of the catalogs with regard to MS. Unlike the MS reported by major international centers, such as National Earthquake Information Center of United States Geological Survey (NEIC USGS) and the International Seismological Centre (ISC), for earthquakes occurring at shallow and crustal depths up to 50–60 km, MS,MOS is also determined for intermediate-depth and deep earthquakes. The analysis of depth corrections to MS was based on MS,MOS from the GS RAS Seismological Catalog and MW from the ISC-GEM (Global Earthquake Model) Catalogue for 736 earthquakes of North Eurasia with MW ≥ 5.5 for the period 1988 through 2014. It was found that the decrease in MS,MOS with increasing depth becomes noticeable for h > 40 km. For the earthquakes of h > 40 km, we found two increasing log linear relations for the correction of MS,MOS as function of depth: ΔMS,MOS(h) = 1.71·log(h) − 2.726 for h = 40–90 km and ΔMS,MOS(h) = 0.556·lg(h)− 0.508 for h > 90 km. We applied these corrections to MS,MOS and found a substantially better correlation and lower standard errors in the MS,MOS vs MW relation. Applying the corrections to MS,MOS of the Okhotsk Sea earthquake on May 24, 2013, h = 617 km showed a good agreement between the corrected MS,MOS = 8.4 and MW = 8.3.

Оценка инвестиционной привлекательности региональных облигаций Оренбургской области в условиях смягчения денежно-кредитной политики и глобальной неопределенности

The relevance of the research is that regional bonds are not only a source of covering the region’s public debt, but also a tool for investment. Currently, the investment attractiveness of such instruments is low, since they are not liquid enough and are low-yielding. In the context of global uncertainty and monetary policy easing, regional bonds can be considered as an alternative investment tool, since they have a fairly high reliability and low investment risk. The purpose of the research is to assess the investment attractiveness of regional bonds of the Orenburg region. The main results are as follows. The comparative characteristics of the Moscow exchange indices on the terms and depth of correction in the securities market in the first half of 2020 are carried out. The dynamics of the exchange rate value of bonds of the Orenburg region (issue # 35003) and the index of municipal bonds are analyzed. It is shown that the bonds of the Orenburg region included in the index of municipal bonds are more stable and conservative financial instruments in comparison with other units of the considered population. The correlation between the yield, price and duration of bonds from the municipal bond index is identified and described based on correlation and regression analysis. To do this, the relationships between the yield and price of bonds were initially estimated using pair regression, and then the yield and duration of the bonds were estimated. As a result, a multi-factor model of multiple regression was built, which allows forecasting the yield of regional bonds. Other factors that are not included in the model and may have an impact on bond yields are indicated. It is shown that in comparison with budget loans, bond loans have a number of advantages: a longer-term nature of attracting funds, availability for a large number of investors, market pricing, the ability to improve the image and investment attractiveness of the Issuer with the help of a credit rating of the region, confirmed by leading rating agencies. The reliability of regional bonds of the Orenburg region was confirmed by the rating Agency Fitch Ratings on June 12, 2020 at the level of «BB+», the forecast is «Stable». It is shown that an additional incentive to purchase sub-Federal bonds by individuals can be a significant tax savings in the framework of opening and active use of an individual investment account.