Centrifugal isolation of SARS-CoV-2: numerical simulation for purification of hospitals' air.

Coronavirus and its spread all over the world have been the most challenging crisis in 2020. Hospitals are categorized among the most vulnerable centers due to their presumably highest traffic of this virus. In this study, centrifugal isolation of coronavirus is successfully deployed for purifying hospitals' air using air conditioners and ducts, suggesting an efficient setup. Numerical simulations have been used to testify the proposed setup due to the complexities of using experimental investigation such as high cost and clinical hazards of the airborne SARS-CoV-2 in the air. Results show that a 20-cm pipe with an inlet velocity of 4 m/s constitutes the best choice for the separation and purification of air from the virus. The proposed scalable method also efficiently separates larger particles, but it can separate smaller particles too. Numerical results also suggest installing the air purifying system on the floor of the hospitals' room for maximum efficiency.

Effect of Transcutaneous Electrical Nerve Stimulation on the Pain Intensity During Insertion of Needle in Patients Undergoing Spinal Anesthesia: A Randomized Controlled Study.

BACKGROUND AND OBJECTIVES: Needle insertion pain during spinal anesthesia is an unpleasant experience for patients. This study aimed to investigate the effects of Transcutaneous Electrical Nerve Stimulation (TENS) on the pain intensity during the insertion of spinal needles in patients undergoing spinal anesthesia. MATERIALS AND METHODS: In a double-blind clinical trial, 60 candidates for elective Trans Ureteral Lithotripsy surgery under spinal anesthesia were randomly divided into intervention and control groups. The electrodes of the TENS device were placed in the space between L3-L4 and L5-S1 vertebrae. The intensity of pain during insertion of the spinal needle by Visual Analog Scale and the frequency of attempts were recorded. RESULTS: The mean age of the study samples was 34.26 ± 5.07 and 32.8 ± 5.28 in the control and intervention group, respectively. The pain intensity during insertion of spinal needles was less significant in the intervention group compared to the control group (p = 0.001). The number of attempts to insert the spinal needle between the two groups was not statistically significant (p = 0.51). The duration of spinal anesthesia implementation procedure by physician in the intervention group was significantly shorter than that of the control group (p = 0.001). CONCLUSION: The use of TENS effectively reduced the pain of spinal needle insertion. Considering these beneficial effects, it is suggested that this procedure be used to relive pain in patients with spinal anesthesia.

Measuring Left Ventricular Volumes in Two-Dimensional Echocardiography Image Sequence Using Level-set Method for Automatic Detection of End-Diastole and End-systole Frames.

BACKGROUND: Identifying End-Diastole (ED) and End-Systole (ES) frames is highly important in the process of evaluating cardiac function and measuring global parameters accurately, such as Ejection Fraction (EF), Cardiac Output (CO) and Stroke Volume. OBJECTIVES: The current study aimed to develop a new method based on measuring volume changes in Left Ventricle (LV) during cardiac cycle. MATERIAL AND METHODS: For this purpose, the Level Set method was used both in detecting endocardium border and quantifying cardiac function of all frames. RESULTS: Demonstrating LV volumes displays ED and ES frames and the volumes used in calculating the required parameters. CONCLUSIONS: Since ES and ED frames exist in iso-volumic phases of the cardiac cycle with minimum and maximum values of LV volume signals, such peaks can be utilized in finding related frames.