Posture and low back pain during pregnancy — 3D study

Objectives: Back pain is a common complaint of pregnant women. The posture, curvatures of the spine and the center of gravity changes are considered as the mechanisms leading to pain. The study aimed to assess spinal curvatures and static postural characteristics with three-dimensional surface topography and search for relationships with the occurrence of back pain complaints among pregnant women. Material and methods: The study was conducted from December 2012 to February 2014. Patients referred from University Clinic of Gynecology and Obstetrics were examined outpatient at the Posture Study Unit of Department of Orthopaedics and Traumatology. Sixty-five women at 4–39 weeks of pregnancy were assessed and surveyed with Oswestry Disability Index; posture was evaluated using surface topography. Results: The study confirmed that difficulties in sitting and standing are significant in the third trimester of the pregnancy. The overall tendency for significant lumbar curvature changes in pregnant women was not confirmed. Major changes in sagittal trunk inclination in relation to the plumb line were not observed in the study group. Conclusions: The issue regarding how the pregnancy causes changes in spinal curvature and posture remains open for further studies. Presented method of 3D surface topography can reveal postural changes, but that requires several exams of each subject and strict follow-up of the series of cases

Cardiac Surgery is Associated with Biomarker Evidence of Neuronal Damage

BACKGROUND: Anesthesia and surgery is commonly associated with central nervous system sequelae and cognitive symptoms, which may be caused by neuronal injury. Neuronal injury can be monitored by plasma concentrations of the neuronal biomarkers tau and neurofilament light protein (NFL). Currently, there are no studies examining whether neuronal injury varies between surgical procedures. OBJECTIVE: Our aim was to investigate if neuronal damage is more frequent after cardiac than after otolaryngeal surgery, as estimated by tau and NFL concentrations in plasma. METHODS: Blood samples were drawn before, during, and after surgery and concentrations of tau, NFL, Aβ40, and Aβ42 were measured in 25 patients undergoing cardiac surgery (9 off-pump and 16 on-pump) and 26 patients undergoing otolaryngeal surgery. RESULTS: Tau increased during surgery (1752%, p = 0.0001) and NFL rose seven days post-surgery (1090%, p < 0.0001) in patients undergoing cardiac surgery; even more in patients on-pump than off-pump. No changes were observed in patients undergoing otolaryngeal surgery and only minor fluctuations were observed for Aβ40 and Aβ42. CONCLUSION: Cardiac surgery is associated with neuronal injury, which is aggravated by extracorporeal circulation. Analyses of NFL and tau in blood may guide development of surgical procedures to minimize neuronal damage, and may also be used in longitudinal clinical studies to assess the relationship of surgery with future neurocognitive impairment or dementia

Experimental study of smog microphysical and optical vertical structure in the Silesian Beskids, Poland

This study presents the vertical profiles of aerosol optical and microphysical properties obtained from cable car and ground-based measurements in the Silesian Beskids, Poland. The data were collected during a measurement campaign between 25 February and March 11, 2018. An AE-51 micro-aethalometer and PMS7003 and OPC-N2 optical particle counters were mounted on the cable car and used to measure the profiles of equivalent of black carbon (eBC) concentration and aerosol size distribution. In situ measurements of the optical properties of the aerosols were obtained using an AE-31 aethalometer and photoacoustic devices. A prototype lidar was used to determine the planetary boundary layer (PBL) height and the aerosol layers. In the middle phase of the study (1–6 March 2018), significant night-time temperature inversions were observed. During the inversion period, the parameters describing the amount of aerosols in the air increased significantly. The concentration of eBC exceeded the level of 15 μg/m3 several times, with an average level of 5.39 ± 4.42 μg/m3. Conversely, the results obtained in the first and third phases of the experiment were at the level of the aerosol background, being 1.45 ± 0.88 μg/m3 and 0.90 ± 0.95 μg/m3, respectively. Significant differences were also observed in the vertical profiles of PM10 mass and eBC concentration. In the middle phase of the study, the profiles showed a significant reduction in the concentration of pollutants with height, while in the first and third phases, there were slight variations with height

Estimation of the Increase in Projectile Velocity in the Intermediate Ballistics Period

The idea of the application of internal ballistics models together with external ballistics models in fire control systems encounters a problem in relating the calculated muzzle velocity value to the initial velocity value used in external ballistics calculations. The difference between these two values is caused by the action on the projectile of the propellant gases exiting from the muzzle. In this paper an attempt has been made to estimate the increase in projectile velocity outside the muzzle by the use of CFD modelling. The commercial ANSYS FLUENT code has been used together with our own 1D model for the internal ballistics period. Calculations have been performed for various launching systems, from small arms to a 155 mm calibre gun. Conclusions have been drawn concerning the magnitude of the increase in projectile velocity outside the muzzle. The main conclusion is that the velocity increase is generally less than 1% and in most cases can be neglected

Simulations of the Gasodynamic Flow Induced by Air Discharge Ejectable from the Barrel by the Projectile

W artykule przedstawiono wyniki symulacji numerycznych wypływu powietrza wypychanego z lufy w wyniku ruchu pocisku podczas strzału na podstawie parametrów przepływu powietrza w lufie przed pociskiem. Stanowi to pierwszy etap symulacji przepływu w okresie balistyki przejściowej. Obliczenia numeryczne przeprowadzono w programie ANSYS Fluent 12.1 dla lufy kalibru 30 mm oraz poruszającego się w niej pocisku TP-T 30 x 173 mm naboju z prochem NC 1316. Porównano wyniki symulacji z publikowanymi w literaturze wynikami badań doświadczalnych i otrzymano jakościową zgodność wyników doświadczalnych z wynikami otrzymanymi na drodze symulacji.In the paper, the results of numerical simulations of air flow from the barrel of ejectable by the movement of the projectile during the shot on the parameters of air flow in the barrel before the bullet are presented. This represents the first phase flow simulation during the intermediate ballistics. Numerical calculations were performed in the ANSYS Fluent 12.1 to 30 mm caliber gun, and moving in the TP-T projectile 30 x 173 mm round with gunpowder NC 1316. Simulation results were compared with published findings in the literature and experienced qualitative agreement of results obtained with the experimental results obtained through simulation

An Approximate Model for the Theoretical Prediction of the Velocity Increase in the Intermediate Ballistics Period

This paper is a continuation of an earlier work [1] by the authors devoted to CFD modelling of the intermediate ballistics period. A semi-analytical model is proposed based on the analytical solution of the Prandtl-Meyer expansion for an approximate assessment of the magnitude of the velocity increase in the intermediate period. Two variants of the model provide upper and lower estimates of the velocity increase. A comparison of these estimates with the results of CFD modelling gives a similar magnitude for the velocity increase. A formula is proposed for a simple estimation of the velocity increase that can be used to calculate a correction to the muzzle velocity value obtained by internal ballistics models