Acoustic Signature: a therapeutic ultrasound guidance technique with submillimeter accuracy

SummaryVitamin K status was evaluated using coagulation studies and/ or vitamin IQ assays in a total of 53 normal fetuses and 47 neonates. Second trimester fetal blood samples were obtained for prenatal diagnosis under ultrasound guidance. Endogenous vitamin K1 concentrations (determined by high performance liquid chromatography) were substantially lower than maternal levels. The mean maternal-fetal gradient was 14-fold at mid trimester and 18-fold at birth. Despite low vitamin K levels, descarboxy prothrombin, detected by a staphylocoagulase assay, was elevated in only a single fetus and a single neonate.After maternal oral supplementation with vitamin K1, cord vitamin K1 levels were boosted 30-fold at mid trimester and 60 fold at term, demonstrating placental transfer. However, these levels were substantially lower than corresponding supplemented maternal levels. Despite elevated vitamin K1 concentrations, supplemented fetuses and neonates showed no increase in total or coagulant prothrombin activity. These results suggest that the low prothrombin levels found during intrauterine life are not due to vitamin K deficiency.

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АКУСТИЧНА ПОМІТНІСТЬ БЕЗПІЛОТНИХ ЛІТАЛЬНИХ АПАРАТІВ З СИЛОВИМИ УСТАНОВКАМИ НА БАЗІ ПОРШНЕВИХ ДВИГУНІВ

Open Information and Computer Integrated Technologies ◽

10.32620/oikit.2020.88.05 ◽

2020 ◽

pp. 62-80

Author(s):

В. В. Руденко ◽

И. В. Калужинов ◽

Н. А. Андрущенко

Keyword(s):

Control System ◽

Internal Combustion Engine ◽

Power Plants ◽

Combustion Engine ◽

Spectral Characteristics ◽

Experimental Studies ◽

Internal Combustion ◽

Detection Range ◽

Acoustic Signature ◽

Static Conditions

The presence in operation of many prototypes of UAVs with propeller propellers, the use of such devices at relatively low altitudes and flight speeds makes the problem of noise reduction from UAVs urgent both from the point of view of acoustic imperceptibility and ecology.The aim of the work is to determine a set of methods that help to reduce the visibility of UAVs in the acoustic range. It is shown that the main source of noise from the UAV on the ground is the power plant, which includes the engine and the propeller. The parameters of the power plants influencing the processes that determine the acoustic signature of the UAV were investigated. A comprehensive analysis of the factors affecting visibility was carried out. The power plants include two-stroke and four-stroke engines, internal combustion and two-blade propellers. The use of silencers on the exhaust of the internal combustion engine was considered. The spectral characteristics of the acoustic fields of the propeller-driven power plants for the operating sample of the UAV "Eco" were obtained. The measurements were carried out in one-third octave and 1/48 octave frequency bands under static conditions. The venue is the KhAI airfield. Note that the propellers that were part of the power plants operated at Reynolds numbers (Re0,75<2*105), which can significantly affect its aerodynamic and acoustic characteristics. It is shown that when choosing a UAV control system, one should take into account the fact that two-stroke piston engines are the dominant source in the noise of propeller-driven control systems in the absence of a hood and mufflers in the intake and exhaust tracts. The use of a four-stroke internal combustion engine significantly reduces the noise of the control system. In the general case, the position of the boundaries of the zone of acoustic visibility of a UAV at the location of the observer is determined by the ratio between the intensity of acoustic radiation perceived by the observer from the UAV and the intensity of sound corresponding to the natural acoustic background and depends on the degree of manifestation of acoustic effects accompanying the propagation of sound in a turbulent atmosphere - the refraction of sound waves. Absorption and dissipation of acoustic energy. The calculation and comparison of the UAV detection range was carried out taking into account the existing natural maskers.The results of experimental studies are presented that allow assessing the degree of acoustic signature of the UAV. A set of measures aimed at reducing the intensity of the acoustic signature of the UAV in various regions of the radiation spectrum has been determined.

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Effect of therapeutic ultrasound on calcific supraspinatus tendinitis

Mymensingh Medical Journal ◽

10.3329/mmj.v16i1.245 ◽

2007 ◽

Vol 16 (1) ◽

Cited By ~ 2

Author(s):

MH Rahman ◽

SZ Khan ◽

MS Ramiz

Keyword(s):

Therapeutic Ultrasound ◽

Supraspinatus Tendinitis

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AORTA Registry 7F vs 11-12 F access

Journal of Endovascular Resuscitation and Trauma Management ◽

10.26676/jevtm.v3i1.79 ◽

2019 ◽

Vol 3 (1) ◽

Cited By ~ 1

Author(s):

Reviewer Joseph DuBose ◽

Jonathan Morrison ◽

Megan Brenner ◽

Laura Moore ◽

John B Holcomb ◽

...

Keyword(s):

Ultrasound Guidance ◽

Balloon Occlusion ◽

Aortic Occlusion ◽

Severely Injured ◽

Distal Extremity ◽

Low Profile ◽

Transfusion Requirements ◽

Thrombotic Complications ◽

Device Use ◽

Endovascular Balloon Occlusion

ABSTRACT Introduction: The introduction of low profile devices designed for Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) after trauma has the potential to change practice, outcomes and complication profiles related to this procedure. Methods: The AAST Aortic Occlusion for Resuscitation in Trauma and Acute Care Surgery (AORTA) registry was utilized to identify REBOA patients from 16 centers -comparing presentation, intervention and outcome variables for those REBOA via traditional 11-12 access platforms and trauma-specific devices requiring only 7 F access. Results:From Nov 2013-Dec 2017, 242 patients with completed data were identified, constituting 124 7F and 118 11-12F uses. Demographics of presentation were not different between the two groups, except that the 7F patients had a higher mean ISS (39.2 34.1, p = 0.028). 7F device use was associated with a lower cut-down requirement for access (22.6% vs. 37.3%, p = 0.049) and increased ultrasound guidance utilization (29.0% 23.7%, p = 0.049). 7F device afforded earlier aortic occlusion in the course of resuscitation (median 25.0 mins vs. 30 mins, p = 0.010), and had lower median PRBC (10.0 vs. 15.5 units, p = 0.006) and FFP requirements (7.5 vs. 14.0 units, p = 0.005). 7F patients were more likely to survive 24 hrs (58.1% vs. 42.4%, p = 0.015) and less likely to suffer in-hospital mortality (57.3% vs. 75.4%, p = 0.003). Finally, 7F device use was associated with a 4X lower rate of distal extremity embolism (20.0% vs. 5.6%, p = 0.014;OR 95% CI 4.25 [1.25-14.45]) compared to 11-12F counterparts. Conclusion: The introduction of trauma specific 7F REBOA devices appears to have influenced REBOA practices, with earlier utilization in severely injured hypotensive patients via less invasive means that are associated with lower transfusion requirements fewer thrombotic complications and improved survival. Additional study is required to determine optimal REBOA utilization.

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