Simon Chivi

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Simon Chivi

Simon Chivi

@SimonChivi

Interventional Radiologist at St Luke’s University Health Network in the Lehigh Valley PA, former Fellow at Icahn School of Medicine at Mount Sinai ⛷️⛵️📰

New York, USA Katılım Şubat 2021
672 Takip Edilen153 Takipçiler
Simon Chivi
Simon Chivi@SimonChivi·
@Object_Zero_ Use it daily in interventional radiology. It’s a phenomenal alloy. Thanks DoD!
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Object Zero
Object Zero@Object_Zero_·
Nitinol (NiTi) Never heard of it? Ninitol the name of a Nickel-Titanium alloy in approx 50-50 composition. The world hardly uses any nitinol at all, because it’s kinda expensive, and it’s because of process chemistry, but it’s a super interesting engineering material with incredible properties. Here’s why we should use it more… It has a combination of steel’s strength but has super elasticity up to 8% elongation in its stress/strain curve, this means it can bend, stretch and twist a lot and then still return to its original shape. It has shape memory. This makes it super compliant in assemblies, reducing demands of precision. Often… A single Ninitol spacer can soak up all your tolerance stack ups, and save you $$$ of precision machining cost (see the curve below). Few mechanical designers have any experience with super elastics metals, but think of gaskets and seals, springs, cages, clutches, torque limiters, the list is long. Shape memory is the ability of nitinol to undergo deformation, stay in its deformed shape when the external force is removed, and then recover its original undeformed shape when you heat it above its transformation temperature. Superelasticity is the ability for the metal to undergo large deformations and immediately return to its undeformed shape upon removal of the external load. Nitinol can undergo elastic deformations 10 to 30 times larger than alternative metals. Ninitol has both of these unusual behaviours. Whether nitinol behaves with shape memory effect or superelasticity depends on whether it is above its transformation temperature during the action. You can tailor the transformation temperature from -20°C to 110°C (-4°F to 230°F). It’s highly biocompatible, and you can put the transformation temperature in human bodyheat range. There are lots of clever design uses of these two behaviours and almost zero real world examples. Ninitol is vastly unexploited, the global economy use 5,000 tonnes / year. We should be using 200x that amount. Self regulating thermal control, heat harvesting, mechanical compliance, there are huge problems that are ignorant of existing material solutions. I find it puzzling that robotics companies aren’t building ninitol actuators. It’s practically a sort of metallic muscle tissue if you cut a mesh and twist it round a mandrel. It should be a foundational smart material that we should be exploiting by now. 5kT/yr is pitiful.
Object Zero tweet mediaObject Zero tweet media
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Roger Seheult, MD
Roger Seheult, MD@RogerSeheult·
Patients in my hospital were put on ventilators when they couldn't breathe anymore, when their respiratory rates were in their 50s, saturations were in the 70-80s, they became unconscious and couldn't protect their anyway or had just coded and were being resuscitated. We hated intubating because it could briefly make them more unstable and spread the virus around. Dead patients don't get Ventilator-associated complications.
Elon Musk@elonmusk

Yes x.com/i/grok/share/R…

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Paul Peterson
Paul Peterson@PaulPetersonMD·
One possible solution to the prior authorization dilemma is to mandate insurance companies must publish their criteria for medical necessity and these MUST be integrated into the electronic medical record order entry platforms such that when an order is placed one may pick appropriate indication(s) on the order based upon the insurance the patient has. This directly is available to the insurance company and they process the order based upon their review of it meets criteria. If they have a concern they have to use integrated chat within EMR on what the order failed review. In over 20 years the only times a prior authorization failed for me was when the patient did not divulge they already had the neuroimaging I requested in the recent past and the insurance knew that. A lot of time could be saved for everyone if the process was more efficient.
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Ali Haider MD
Ali Haider MD@yourheartdoc1·
Trying to get a prior authorization approved for a patient of mine who needs a cardiac procedure. Initially not approved , submitted more info, a week later still not approved and requested a peer to peer (phone call w insurance doctor) my staff called three times... (1/2)
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Simon Chivi
Simon Chivi@SimonChivi·
For those who missed it here's the link: Transradial Genicular Artery Embolization (GAE) for Knee Osteoarthritis (OA) (youtube.com)
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Simon Chivi
Simon Chivi@SimonChivi·
Tune in to Chicago’s Amputation Prevention Symposium as @RSP516 @roblookstein and myself perform a CLTI SFA revascularization at 8 am EST 8/14! Live from New York @MountSinaiIR !
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Simon Chivi
Simon Chivi@SimonChivi·
@olsonplanner If they’re going to axe SAVE then they have to restart/let us go back to PAYE at least right?
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Tyler Olson, EA
Tyler Olson, EA@olsonplanner·
Everyone on SAVE has PSLF payments halted temporarily. Interest accrual is also paused. Changing to IBR, if you’re eligible, may or may not be wise. It depends on how long this drags out. And no one can possibly say.
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Simon Chivi
Simon Chivi@SimonChivi·
Reopened a thrombosed TIPS, crossed with 5Fr MPA. Plastied and relined with 7 cm viatorr. Gradient 11 mmHg. HEP gtt and Asa 81 mg for now. Now off to pack for #SIR24SLC
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Dr. Longissimus
Dr. Longissimus@DrLongissimus·
Throwback to med school when one of my friends brought his stethoscope to his radiology rotation and one of the radiologists asked him to go auscultate the MRI machine and tell him "what kind of lub dub it makes" that's when I knew I wanted to become a radiologist
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Endovascular Today
Endovascular Today@EVToday·
Vivian L. Bishay, MD (@vivianbishay), introduces our embolization series, which features the work of those who are not only studying today’s cutting-edge applications but also proving their utility & integrating their application into real-world practice. evtoday.com/articles/2024-…
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