Evaluation of 86 Patients Whom Death While Being Followed up with Pre-Diagnosis of Covid-19

The Coronavirus-19 pandemic continues at full speed, and the number of patients who die from Covıd-19 is increasing. It was aimed to evaluate the demographic information and laboratory findings of 86 patients who died while being followed up in our hospital with a pre-diagnosis of Covıd-19. Identifying these characteristics of deceased patients will be essential to guide clinicians in identifying critically ill patients. Data on demographic information, comorbidities, time from hospitalization to death, molecular test results, thorax CT findings, biochemical findings, culture, antibiotic susceptibility, and the given treatments of the cases were collected from the electronic system Kastamonu Training and Research Hospital. While the RT-PCR test of 21 of the cases was positive, in 9 of the cases, control PCR tests were negative after a while. The CT results of 18 of the 21 initially RT-PCR positive cases were compatible with Covid-19, and the CT result of 3 could not be reached. When the blood test results of the cases were examined, neutrophil increase, white blood cell increase, lymphocyte reduction, and inflammatory markers increase were determined. A total of 43 bacterial growths were found in 21 cases. It has been observed that deaths in patients who were followed up with the pre-diagnosis of Covıd-19 generally occur in older people, males, and those with underlying diseases. It was thought that the cause of death could be underlying diseases, pathologies caused by inflammation, and secondary bacterial infections in addition to viral infection. Clinicians should be more careful about elderly patients, patients with secondary bacterial infections, or patients with neutrophilia, lymphopenia.

Sensitivity of the Spool Rate on the Dynamic Response of the System

In rotodynamic systems, the rotor is spooled up from zero speed to its operating speed during the engine start. One of the considerations in design of rotating systems is the placement of rotor critical speed. It is vital to ensure that the rotor critical speeds are not close to the engine operating speed. However, it is not always possible to isolate all the frequencies above the operating speed. So, during the engine start to full speed, rotor system does travel through the mode. Therefore, to avoid a large system response, the rotor is spooled up quickly through the critical speed. In addition to the rotor critical speeds, the natural frequencies of the static structures may also get excited during the rotor spool up and spool down. The static structure response is one of the important considerations in designing a system for dynamic loading condition. It has been observed that the rotor spool rate affects the static structure response. This paper focuses on effect on system’s response under various spool rate. It has also been shown that the natural frequency of the system and damping in the system are two of the major factors towards sensitivity of system response with spool rate. Additionally, it has been observed that the presence of non-linearities shifts the peak response away from the natural frequency depending on the spool rate and spool direction.

New requirements for training personnel for railway transport

The problem of vocational training of specialists is one of the most essential questions in vocational education.Industrial enterprises (and not only railway transport), are currently forced to spend much money and time on additional training of their new employees (specialists), who experience serious difficulties when working. The theoretical training of a young specialist even he (or she) is hardworking, discipline and pass in for his work sometimes doesn't correspond to the real facts at works. The change in the system of the vocational education is necessity now days. These changes are connected with the necessity to improve the training of the students.In the conditions when reform of the system of the vocational education is full speed and the teachers are in search of new educational models the problem of the trained skilled workers claimed in the labor market is in great need. It must be an energetic, curious, creative person capable to show his skill and to react quickly on the changes in the society especially in the professional and social sphere. The main task of the contemporary educational institution is training of such graduating students.Modernization as being an important reserve for the reorganization and renovation of the education system in accordance with the contemporary demands puts the task: to bring in accordance with the social and economical needs of the country to establish communication with the works.The improvement of the vocational education will be of great importance not only for the development of the railway transport but for the whole country, it will give a push to the positive changes in the others branches of industry.

Sensorless Predictive Current Control of a Permanent Magnet Synchronous Motor Powered by a Three-Level Inverter

Permanent magnet synchronous motors and their relevant control techniques have become more and more prevalent in electric vehicle driving applications because of their outstanding performance. This paper studies a simple and effective sensorless scheme based on a current observer for a permanent magnet synchronous motor powered by a three-level inverter, which avoids the injection of a high-frequency signal and the observation of back-electromotive force. In this way, a current observer is constructed to observe d–q-axes currents by relying on an extended-current model. Thereafter, the position and speed of the machine can be extracted from two PI controllers associated with the d–q-axes current-tracking errors. Meanwhile, it takes into account the model predictive current control with neutral-point voltage balance to maintain the stability of the three-level inverter system. In general, this scheme realizes sensorless operation in a full-speed domain and is no longer limited by the types of inverter and method used.

Diagnostic capabilities of magnetic susceptibility-weighted images in traumatic brain injury in children

Introduction. In MRI, the difference in sensitivity between tissues is used to obtain images weighted by the inhomogeneity of the magnetic field termed susceptibility-weighted imaging (SWI) and a high-resolution 3D radiofrequency gradient echo scan with full speed compensation is applied. The aim was to determine the features of lesions caused by traumatic brain injury in children using the SWI sequence. Materials and methods. 535 TBI children aged two months up to 18 years old (average age 9.58 ± 1.5) were studied. There were 325 boys (60.7%), 210 girls (39.3%). MRI was performed without and with intravenous contrast on a Phillips Achieva 3 T scanner with T1- and T2WI, 2D and 3D images, FLAIR, magnetic resonance angiography (TOF MRA), SWI, and DW/DTI, MRS and fMRI, SWI were used for visualization of DAI. Results. Patients included children with severe TBI - 178 (33.3%), moderate TBI - 172 (32.1%) and mild TBI - 185 (34.6%). Of the 535 injured children, 129 (24.1%) had MRI performed within the first 24 hours from the moment of injury, up to 48 hours - at 91 (17.0%), up to 72 hours - in 78 (14.6%) and up to 13 days - in 237 (44.3%). DAI foci at all degrees of TBI were detected in 422 (78.9%) children out of 535 children. Conclusion. SWI is a sensitive method for diagnosing brain lesions in TBI and significantly contributes to predicting outcomes in the early stages after trauma. The amount of brain lesions diagnosed by SWI correlates with the degree of injury according to the Glasgo Coma Scale. The study of the brain functional connections can inform about possible relationships between the localization of the SWI lesion and cognitive deficits, potentially providing an opportunity to use SWI in the hyperacute phase.

Drill splatter in orthopaedic procedures and its importance during the COVID-19 pandemic

Aims During the COVID-19 pandemic, drilling has been classified as an aerosol-generating procedure. However, there is limited evidence on the effects of bone drilling on splatter generation. Our aim was to quantify the effect of drilling on splatter generation within the orthopaedic operative setting. Methods This study was performed using a Stryker System 7 dual rotating drill at full speed. Two fluid mediums (Videne (Solution 1) and Fluorescein (Solution 2)) were used to simulate drill splatter conditions. Drilling occurred at saw bone level (0 cm) and at different heights (20 cm, 50 cm, and 100 cm) above the target to simulate the surgeon ‘working arm length’, with and without using a drill guide. The furthest droplets were marked and the droplet displacement was measured in cm. A surgical microscope was used to detect microscopic droplets. Results Bone drilling produced 5 cm and 7 cm droplet displacement using Solutions 1 and 2, respectively. Drilling at 100 cm above the target produced the greatest splatter generation with a 95 cm macroscopic droplet displacement using Solution 2. Microscopic droplet generation was noticed at further distances than what can be macroscopically seen using Solution 1 (98 cm). Using the drill guide, there was negligible drill splatter generation. Conclusion Our study has shown lower than anticipated drill splatter generation. The use of a drill guide acted as a protective measure and significantly reduced drill splatter. We therefore recommend using a drill guide at all times to reduce the risk of viral transmission in the operative setting. Cite this article: Bone Jt Open 2021;2(9):752–756.