Revealing the reason behind jet formation at the tip of laser optical fiber — ScienceDaily

When an optical fiber is immersed in liquid, a high temperature, high speed jet is discharged. Researchers expect this to be applied to medical treatment in the future. Now, a research team from Russia and Japan has explored this phenomenon further and revealed the reasons behind the jet formation.

Lasers using a thin optical fiber and combined with an endoscope and catheter can be easily transported into deep areas of the body or inside blood vessels. Traditionally, affected areas or lesions are removed by generating heat inside the tissue through laser absorption — a process known as the photothermal effect.

Yet, hydrodynamical phenomena, such as microbubble formation or high-speed jet generation from the optical fiber, show immense medical promise.

The process of jet formation happens when the laser is irradiated to the water, causing the water to boil and a vapor bubble to form at the tip of the optical fiber. The vapor bubble grows until the laser energy absorbed in the liquid is consumed. Because of the surrounding cold liquid, condensation suddenly shrinks the vapor bubble.

Using a numerical simulation, Dr. Junosuke Okajima from Tohoku University’s Institute of Fluid Science, along with his colleagues in Russia, set out to clarify the jet formation mechanism. Their simulation investigated the relationship between the bubble deformation and the induced flow field.

When the bubble shrinks, the flow toward the tip of the optical fiber is formed. The flow deforms the bubble into the cylindrical shape. This deformation induces the collision of flow in a radial direction. This collision generates the jet forward. As a result of collision and jet formation, the vortex is formed at the tip of the deformed bubble and it grows larger.

“We found the jet velocity depends on the relationship between the size of the vapor bubble just

France’s Health Data Hub to move to European cloud infrastructure to avoid EU-US data transfers

France’s data regulator CNIL has issued some recommendations for French services that handle health data, as Mediapart first reported. Those services should avoid using American cloud hosting companies altogether, such as Microsoft Azure, Amazon Web Services and Google Cloud.

Those recommendations follow a landmark ruling by Europe’s top court in July. The ruling, dubbed Schrems II, struck down the EU-U.S. Data Privacy Shield. Under the Privacy Shield, companies could outsource data processing from the EU to the U.S. in bulk. Due to concerns over U.S. surveillance laws, that mechanism is no longer allowed.

The CNIL is going one step further by saying that services and companies that handle health data should also avoid doing business with American companies — it’s not just about processing European data in Europe. Once again, this is all about avoiding falling under U.S. regulation and rulings.

The regulator sent those recommendations to one of France’s top courts (Conseil d’État). SantéNathon, a group of organizations and unions, originally notified the CNIL over concerns about France’s Health Data Hub.

France is currently building a platform to store health data at the national level. The idea is to build a hub that makes it easier to study rare diseases and use artificial intelligence to improve diagnoses. It is supposed to aggregate data from different sources and make it possible to share some data with public and private institutions for those specific cases.

The technical choices have been controversial as the French government originally chose to partner with Microsoft and its cloud platform Microsoft Azure.

Microsoft, like many other companies, relies on Standard Contractual Clauses for EU-U.S. data transfers. But the Court of Justice of the EU has made it clear that EU regulators have to intervene if data is being transferred to an unsafe country when

Apple climbs as Wedbush says it will benefit from ‘once in a decade’ iPhone 12 launch that spurs strong demand

a hand holding a video game remote control: Reuters

© Reuters

  • Apple surged 4% on Monday ahead of its “Hi, Speed” event on Tuesday, where it’s expected to launch its next-generation iPhone 12.
  • Wedbush said Apple’s iPhone 12 would represent a “once in a decade” launch, kicking off its 5G supercycle.
  • Wedbush said that based on its channel checks, Apple and its suppliers are anticipating “stepped-up demand” for its 6.7-inch iPhone 12 Pro Max.
  • Morgan Stanley said in a note last week that strong demand for Apple’s higher-priced iPhone 12 models could help boost the iPhone’s average selling price, leading to more upside for the stock.
  • Visit Business Insider’s homepage for more stories.

Expectations are high for Apple’s “Hi, Speed” event on Tuesday.

Wedbush said in a note on Sunday that the event, where Apple is expected to launch the iPhone 12, represented a “once in a decade” opportunity for Apple to capitalize on its massive iPhone install base of nearly 950 million users.

Wedbush isn’t alone in thinking that the event will be a big deal for Apple. Morgan Stanley said in a note last week that it expected it to be “the most significant iPhone event in years.”

Shares of Apple jumped 4%, to $121.71, on Monday, leading the market higher and helping technology stocks surge.

Read more: GOLDMAN SACHS: Buy these 15 stocks set to deliver the strongest possible profit growth and subsequent returns through year-end

Wedbush said it expected four new iPhones, including a 5.4-inch iPhone 12 mini and a 6.7-inch iPhone 12 Pro Max, which would be the largest iPhone display ever.

Video: Investors on what a new iPhone could do for Apple’s stock price (CNBC)

Investors on what a new iPhone could do for Apple’s stock price



Morgan Stanley said the 6.7-inch iPhone 12 could cost as

Northwestern Mutual hosting first Women in Tech Conference

a view of a city with tall buildings: The new Northwestern Mutual Tower and Commons, 805 E. Mason St., is the state's second-tallest building at 550 feet and 32 stories. From 10 a.m. to 5 p.m. Saturday and Sunday, visitors will be able to tour sections of the building including the top of the tower.

© Mike De Sisti / Milwaukee Journal Sentinel
The new Northwestern Mutual Tower and Commons, 805 E. Mason St., is the state’s second-tallest building at 550 feet and 32 stories. From 10 a.m. to 5 p.m. Saturday and Sunday, visitors will be able to tour sections of the building including the top of the tower.

Northwestern Mutual will bring together around 2,000 women in technology and their supporters this winter for its first Women in Tech Conference. 

The free virtual conference will take place Dec. 3, Northwestern Mutual announced in a news release Monday. 

The one-day event will focus on professional development, empowerment and collaboration. Northwestern Mutual said the goal of the Women in Tech Conference is to foster a more diverse and inclusive tech industry.


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Former professional boxer Laila Ali will start the conference with a keynote presentation. Breakout sessions will address a range of technology topics and networking opportunities. Executives from companies like Zoom, Hilton and Major League Baseball will participate. 

“Gender equity is important for our teams, businesses and society to thrive, and with technology at the center of everything we do, it’s critical that we close the gender gap in tech careers,” said Sangeetha Rai, vice president, technology customer success at Northwestern Mutual, in a news release. “We’re thrilled to host our first Women in Tech Conference to provide real opportunities to connect, educate and inspire women in technology and continue to advance diversity and inclusion within our company, communities and the industry.”

Sarah Hauer can be reached at [email protected] or on Instagram @HauerSarah and Twitter @SarahHauer. Subscribe to her weekly newsletter Be MKE at 

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Astronomers capture a black hole shredding star into spaghetti strands

  • Astronomers at the European Southern Observatory observed a black hole sucking in a faraway star, shredding it into thin strands of stellar material.
  • This process, known as “spaghettification,” happens because of black holes’ powerful gravitational force.
  • At 215 million light-years away, this spaghettification process is the closest ever observed by astronomers. 
  • Visit Business Insider’s homepage for more stories.

Astronomers have captured a rarely-seen event: a flare of light caused by a black hole devouring a nearby star like spaghetti.

Observed in the Eridanus constellation, about 215 million light-years away from Earth, the star’s destruction is the closest such event astronomers have ever observed. 

“When an unlucky star wanders too close to a supermassive black hole in the center of a galaxy, the extreme gravitational pull of the black hole shreds the star into thin streams of material,” study author Thomas Wevers, a fellow at the European Southern Observatory in Santiago, Chile, said in a press release about the discovery.

This process is called a tidal disruption event – or, more colloquially, “spaghettification,” a nod to the long, thin strands a star becomes as the black hole’s gravity stretches it thinner and thinner. 

When these strands get sucked into the black hole, they release a powerful flare of energy that astronomers can detect, even from hundreds of millions of light-years away. 


A screenshot taken from a video zooming in on the AT2019qiz tidal disruption event, 215 million light-years away. This phenomenon, a blast of light from a star being ripped apart by a supermassive black hole, has been studied by ESO telescopes.

N. Risinger/ESO/Digitized Sky Survey 2

The researchers studied the dying star over a six-month period, using tools including ESO’s Very Large Telescope and its New Technology Telescope, and published their findings in Monthly Notices of the Royal Astronomical Society.