8 research outputs found
USING NONINVASIVE CALIBRATED CUFF PLETHYSMOGRAPHY TO OBSERVE THE EFFECTS OF COLD-WATER IMMERSION ON ARTERIAL COMPLIANCE
As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological response to cold exposure and endothelial function encourage further study of the effects of ice plunging on cardiovascular health. Calibrated cuff plethysmography is a promising method of reflecting on endothelial function by measuring arterial compliance of select blood vessels. In this study, a calibrated cuff plethysmography device was built and tested for efficiency as it was used to measure compliance and cross-sectional area of the brachial artery of 14 participants 30 minutes before, immediately after, and 30 minutes after a 5-minute cold plunge in a temperature of 10°C - 15°C. Results found some significant differences between baseline measurements recorded immediately after the ice plunge and measurements recorded during reactive hyperemia conditions at normal body temperature but did not conclude that 5-minute cold-water immersion intervention had a significant impact on arterial compliance or area overall since this was a short term experiment with only acute intervention methods. The device used was concluded to effectively measure arterial compliance and area
Using Noninvasive Calibrated Cuff Plethysmography to Observe the Effects of Cold-Water Immersion on Arterial Compliance
As the prevalence of cardiovascular diseases continues to exponentially grow in populations across the globe, the necessity of determining underlying factors, effective methods of diagnoses, and universally available preventive measures also grows. Early detection of endothelial dysfunction, a proven precursor of cardiovascular diseases, can be extremely impactful in encouraging preventative measures and early intervention before medical conditions become chronic. In recent years, ice plunging, a form of cryotherapy involving full body immersion in cold water, has gained popularity within circles of fitness and health practitioners, gaining the interest of people of all backgrounds. Certain parallels observed between the human physiological response to cold exposure and endothelial function encourage further study of the effects of ice plunging on cardiovascular health. Calibrated cuff plethysmography is a promising method of reflecting on endothelial function by measuring arterial compliance of select blood vessels. In this study, a calibrated cuff plethysmography device was built and tested for efficiency as it was used to measure compliance and cross-sectional area of the brachial artery of 14 participants 30 minutes before, immediately after, and 30 minutes after a 5-minute cold plunge in a temperature of 10°C - 15°C. Results found some significant differences between baseline measurements recorded immediately after the ice plunge and measurements recorded during reactive hyperemia conditions at normal body temperature but did not conclude that 5-minute cold-water immersion intervention had a significant impact on arterial compliance or area overall since this was a short term experiment with only acute intervention methods. The device used was concluded to effectively measure arterial compliance and area
FeverDots
FeverDots are wearable temperature sensitive stickers that change color from black to pink at 99°F when placed on the temple or forehead. The objective of this project was to develop an efficient manufacturing method for FeverDots, and manufacture a device along with it. To create the FeverDots manufacturing device, the full design process was executed. The team went through a thorough ideation phase before ultimately defining and specifying the scope of the project.
The key customer requirements of this device include that it is lightweight, portable, durable, simple to assemble, easy to use, and able to generate uniform ink and force distribution. One additional requirement from the sponsors was feedback from human use of FeverDots. The key requirements were analyzed and translated into quantifiable engineering specifications. The lightweight and portable requirement is quantified by a 30 lb maximum weight measurement. Durability was also quantified by a maximum total length of cracking in the wood set at 10 inches. A maximum number of 10 steps to go through a full cycle of stamping was set to quantify simple assembly. Ease of use was quantified with a spec of 27 ± 4N required to start the motion of the device. Finally, the device’s ability to generate uniform ink and force distribution was quantified with a 0.015 ± 0.002 g/in2 measurement for dry weight of ink and a minimum of 85% of the sticker paper receiving a uniform application of force per cycle.
An initial conceptual model was developed to test out the initial mechanical ideas; as these ideas were further defined and developed, the final design was selected. The transition from conceptual to final design occurred with a central focus on obtaining equal force and ink distribution. Four total iterations of the prototype were created throughout the life of the project, including the initial and final prototypes. The various iterations were made to fine-tune the ink stamping mechanism and the interactions between assembly pieces.
The team conducted 7 different tests to analyze if it met the specified metrics outlined above. These tests were for: weight and portability, durability, simple assembly, dry weight specification for ink, ink distribution, force uniformity, and minimum force. The purpose of the Weight and Portability test was to identify if the device was not excessively heavy. Next, the Durability test was designed to assess if the parts would be able to remain assembled during stamping, and the Simple Assembly test analyzed if the device requires too many operational steps for use. Also, the Dry Weight Specification of Ink Test allowed the team to observe if the device could apply the correct amount of ink onto the substrate, while the Ink Distribution Test evaluated how well the ink spread across the substrate. Similarly, the Force Uniformity Test noted how force was applied throughout the lid of the device. Lastly, the Minimum Force Test determined if the force threshold to move the device was feasible. To gain data on the human use of FeverDots, a human use study was conducted; survey results were analyzed and presented to our sponsors.
The device achieved uniform force as it met the specification of 85% during the force uniformity test. Additionally, it met the specifications for simple assembly and easy to use as the number of operational steps include only 9 and that it showed to only require a range of 23 N to 31 N to be able to move the lid, respectively. It also passed the portability test as its weight was only 12.2 lbs.
However, it failed the customer requirement of generating uniform ink application. This was revealed as it was unable to meet the specifications of 0.015 g/in² for the dry weight of the ink and 85% of the sticker paper area covered with ink. Lastly, it also failed the durability test as the total crack length summed to over 10 inches
A Multi-surgeon Robotic-guided Thoracolumbar Fusion Experience: Accuracy, Radiation, Complications, Readmissions, and Revisions of 3,874 Screws across Three Robotic Generations
Objective Robotic guidance provides indirect visualization of key anatomic landmarks to facilitate minimally invasive surgery (MIS) and is emerging as a reliable and accurate technique for posterior spine instrumentation. We sought to describe eight years of experience with robotic guidance at a high-volume, multi-surgeon center. We hypothesize that robotic guidance will lead to (1) low rates of complication, readmissions, and revision surgery, (2) reduced fluoroscopic radiation exposure, (3) and accurate thoracolumbar instrumentation. Methods A retrospective review of complications, revision surgery, and readmission rates in patients undergoing thoracolumbar fusion surgery utilizing three robotic generations. Secondary analysis was conducted comparing the three robotic generations for complications, revision surgery, accuracy, and readmission rates along with intraoperative fluoroscopic duration. Results A total of 628 patients (3,874 robotic-guided screws) ages 12–81 years-old (43.9% male) were included in the study. At one year, the cumulative complication incidence was 15.5% with a 10.3% incidence of surgical complications (3.7% wound, 1.2% robot-related, and 5.4% non-robot-related complications). At one year, the revision surgery incidence was 9.4%. There was no statistical difference between complications, readmission, or revision surgery after initial admission among the three robotic generations. The average intraoperative fluoroscopic duration was 53.8 seconds (11.9 seconds per screw and 17.6 seconds per instrumented level). Conclusion Robotic guidance in thoracolumbar instrumented fusions was associated with low complication, revision surgery, and readmission rates. Our results suggest robotic guidance can provide accurate guidance with minimal adverse events in thoracolumbar instrumentation
Presentazione del documento
The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations in the early 2020s. We describe the scientific goals of the experiment, motivate the design, and forecast its performance. SO will measure the temperature and polarization anisotropy of the cosmic microwave background in six frequency bands centered at: 27, 39, 93, 145, 225 and 280 GHz. The initial configuration of SO will have three small-aperture 0.5-m telescopes and one large-aperture 6-m telescope, with a total of 60,000 cryogenic bolometers. Our key science goals are to characterize the primordial perturbations, measure the number of relativistic species and the mass of neutrinos, test for deviations from a cosmological constant, improve our understanding of galaxy evolution, and constrain the duration of reionization. The small aperture telescopes will target the largest angular scales observable from Chile, mapping ≈ 10% of the sky to a white noise level of 2 μK-arcmin in combined 93 and 145 GHz bands, to measure the primordial tensor-to-scalar ratio, r, at a target level of σ(r)=0.003. The large aperture telescope will map ≈ 40% of the sky at arcminute angular resolution to an expected white noise level of 6 μK-arcmin in combined 93 and 145 GHz bands, overlapping with the majority of the Large Synoptic Survey Telescope sky region and partially with the Dark Energy Spectroscopic Instrument. With up to an order of magnitude lower polarization noise than maps from the Planck satellite, the high-resolution sky maps will constrain cosmological parameters derived from the damping tail, gravitational lensing of the microwave background, the primordial bispectrum, and the thermal and kinematic Sunyaev-Zel'dovich effects, and will aid in delensing the large-angle polarization signal to measure the tensor-to-scalar ratio. The survey will also provide a legacy catalog of 16,000 galaxy clusters and more than 20,000 extragalactic sources
The Simons Observatory: Astro2020 Decadal Project Whitepaper
International audienceThe Simons Observatory (SO) is a ground-based cosmic microwave background (CMB) experiment sited on Cerro Toco in the Atacama Desert in Chile that promises to provide breakthrough discoveries in fundamental physics, cosmology, and astrophysics. Supported by the Simons Foundation, the Heising-Simons Foundation, and with contributions from collaborating institutions, SO will see first light in 2021 and start a five year survey in 2022. SO has 287 collaborators from 12 countries and 53 institutions, including 85 students and 90 postdocs. The SO experiment in its currently funded form ('SO-Nominal') consists of three 0.4 m Small Aperture Telescopes (SATs) and one 6 m Large Aperture Telescope (LAT). Optimized for minimizing systematic errors in polarization measurements at large angular scales, the SATs will perform a deep, degree-scale survey of 10% of the sky to search for the signature of primordial gravitational waves. The LAT will survey 40% of the sky with arc-minute resolution. These observations will measure (or limit) the sum of neutrino masses, search for light relics, measure the early behavior of Dark Energy, and refine our understanding of the intergalactic medium, clusters and the role of feedback in galaxy formation. With up to ten times the sensitivity and five times the angular resolution of the Planck satellite, and roughly an order of magnitude increase in mapping speed over currently operating ("Stage 3") experiments, SO will measure the CMB temperature and polarization fluctuations to exquisite precision in six frequency bands from 27 to 280 GHz. SO will rapidly advance CMB science while informing the design of future observatories such as CMB-S4
The Simons Observatory: Astro2020 Decadal Project Whitepaper
International audienceThe Simons Observatory (SO) is a ground-based cosmic microwave background (CMB) experiment sited on Cerro Toco in the Atacama Desert in Chile that promises to provide breakthrough discoveries in fundamental physics, cosmology, and astrophysics. Supported by the Simons Foundation, the Heising-Simons Foundation, and with contributions from collaborating institutions, SO will see first light in 2021 and start a five year survey in 2022. SO has 287 collaborators from 12 countries and 53 institutions, including 85 students and 90 postdocs. The SO experiment in its currently funded form ('SO-Nominal') consists of three 0.4 m Small Aperture Telescopes (SATs) and one 6 m Large Aperture Telescope (LAT). Optimized for minimizing systematic errors in polarization measurements at large angular scales, the SATs will perform a deep, degree-scale survey of 10% of the sky to search for the signature of primordial gravitational waves. The LAT will survey 40% of the sky with arc-minute resolution. These observations will measure (or limit) the sum of neutrino masses, search for light relics, measure the early behavior of Dark Energy, and refine our understanding of the intergalactic medium, clusters and the role of feedback in galaxy formation. With up to ten times the sensitivity and five times the angular resolution of the Planck satellite, and roughly an order of magnitude increase in mapping speed over currently operating ("Stage 3") experiments, SO will measure the CMB temperature and polarization fluctuations to exquisite precision in six frequency bands from 27 to 280 GHz. SO will rapidly advance CMB science while informing the design of future observatories such as CMB-S4
Analysis of Outcomes in Ischemic vs Nonischemic Cardiomyopathy in Patients With Atrial Fibrillation A Report From the GARFIELD-AF Registry
IMPORTANCE Congestive heart failure (CHF) is commonly associated with nonvalvular atrial fibrillation (AF), and their combination may affect treatment strategies and outcomes