Until now, Serbia was the only European country refusing to support sanctions imposed on the Russian Federation due to its invasion of Ukraine. But classified documents revealed through an intelligence information leak tell a new story.

This information has been revealed when a large number of U.S. official documents have been posted online in a couple of last weeks. The leak is already classified as one of the most serious U.S. security breaches in recent history.

Serbia did not confirm these statements. The country’s Defense Minister Milos Vucevic said today that the intelligence information is not true.

“Serbia did not, nor will it be selling weapons to the Ukrainian nor the Russian side, nor to countries surrounding that conflict,” Milos Vucevic commented on the current situation.

The Pentagon document titled “Europe|Response to Ongoing Russia-Ukraine Conflict” presents the “assessed positions” of 38 European governments depicting their response to Ukraine’s requests for military assistance. Information is presented in a chart form.

The document dated March 2 says that Serbia committed to sending military assistance to Ukraine and is willing to continue providing weapons to Ukraine in the future. The country, however, did not agree to provide training to Ukrainian forces.

Serbia had repeatedly condemned the war and the Russian aggression, but this may be the first time this country decided to unequivocally support Ukraine.

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Researchers have completed the most advanced brain map to date, that of an insect, a landmark achievement in neuroscience that brings scientists closer to true understanding of the mechanism of thought.

The team, led by researchers at Johns Hopkins University and the University of Cambridge, produced a detailed diagram, or connectome, tracing every neural connection in the brain of a larval fruit fly, an archetypal scientific model with brains comparable to humans.

The U.S. National Science Foundation-supported work, likely to underpin future brain research and to inspire new machine learning architectures, appears in the journal Science.

Mapping fruit fly brain

“If we want to understand who we are and how we think, part of that is understanding the mechanism of thought,” said senior author Joshua Vogelstein of Johns Hopkins. “And the key to that is knowing how neurons connect with each other.”

The team’s connectome of a fruit fly, Drosophila melanogaster, is the most complete as well as the most expansive map of an entire insect brain ever completed. It includes 3,016 neurons and every connection between them: 548,000. Vogelstein said that “everything has been working up to this.”

Even with the best modern technology, mapping whole brains is difficult and extremely time-consuming. Getting a complete cellular-level picture of a brain requires slicing the brain into hundreds or thousands of individual tissue samples, all of which have to be imaged with electron microscopes before the painstaking process of reconstructing all those pieces, neuron by neuron, into a full, accurate portrait of a brain.

The researchers chose the fruit fly larva because, for an insect, the species shares much of its fundamental biology with humans, including a comparable genetic foundation. It also has rich learning and decision-making behaviors, making it a useful model organism in neuroscience. And for practical purposes, its relatively compact brain can be imaged and its circuits reconstructed in a reasonable timeframe.

The team charted every neuron and every connection, and categorized each neuron by the role it plays in the brain. They found that the brain’s busiest circuits were those that led to and away from neurons of the learning center.

The methods developed are applicable to any brain connectome project, and their code is available to whomever attempts to map an even larger animal brain, Vogelstein said, adding that despite the challenges, scientists are expected to take on the mouse, possibly within the next decade.

“Having connectomes, such as the fly brain connectome developed here, for diverse organisms will open the brain up to everyone — schoolchildren, citizen scientists, researchers and others curious about the inner workings of the brain,” said Edda Thiels, a program director in NSF’s Division of Biological Infrastructure.

Source: NSF

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Compared to those who live at sea level, the 2 million people worldwide who live above an elevation of 4,500 meters (14,764 feet) — about the height of Mount Rainier, Mount Whitney, and many Colorado and Alaska peaks — have lower rates of metabolic diseases, such as diabetes, coronary artery disease, hypercholesterolemia, and obesity.

The work of U.S. National Science Foundation-supported researchers at Gladstone Institutes has shed new light on this phenomenon. 

The scientists showed that exposure to chronically low oxygen levels, such as those experienced at high elevations, rewired how mice burn sugars and fats. The results, published in the journal Cell Metabolism, help explain the metabolic differences of people who live at high altitudes and could lead to new treatments for metabolic disease.

“When an organism is exposed to chronically low levels of oxygen, different organs reshuffle their fuel sources and their energy-producing pathways,” says Isha Jain, senior author of the new study. “We hope these findings will help us identify metabolic switches that might benefit metabolism even outside of low-oxygen environments.”

At sea level, where a third of the world’s population lives, oxygen makes up about 21% of our air. But people who live above 4,500 meters, where oxygen makes up just 11% of the air, can adapt to the shortage of oxygen — known as hypoxia — and thrive.

Researchers studying the impact of hypoxia have usually carried out their research in isolated cells or in cancerous tumors, which often lack oxygen. Jain’s group wanted a better look at how long-term hypoxia impacts organs throughout the body.

Jain and colleagues at Gladstone and the University of California, San Francisco, housed adult mice in pressure chambers containing 21%, 11% or 8% oxygen — all levels humans and mice can survive. Over three weeks, the researchers observed the animals’ behavior, monitored their temperature, carbon dioxide levels and blood glucose, and used positron emission tomography (PET) scans to study how different organs consumed nutrients and what is the level of their metabolism.

In the first days of hypoxia, the mice living in 11% or 8% oxygen moved around less, spending hours completely still. However, by the end of the third week, their movement patterns had returned to normal.

Similarly, carbon dioxide levels in their blood — which usually decrease when mice or humans breathe faster to try to get more oxygen — initially decreased but returned to normal levels by the end of the three weeks.

The animals’ metabolism, however, seemed more permanently altered by the hypoxia. For animals housed in the hypoxic cages, blood glucose levels and body weight both dropped, and neither returned to pre-hypoxic levels.

These metabolism changes mirror those in humans who live at high altitudes, and are associated with a lower risk of diseases, including cardiovascular disease. Understanding how hypoxia contributes could lead to new drugs that mimic these beneficial effects.

Source: NSF

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Simulating solar flares on a scale the size of a banana, researchers at Caltech have parsed out the process by which these massive explosions blast potentially harmful energetic particles and X-rays into the cosmos.

Corona loops are arches of plasma that protrude from the surface of the sun, aligned along magnetic field lines. The magnetic field lines act like highways for charged particles, guiding the motion of the electrons and ions that comprise plasma.

The loops, which may project 100,000 kilometers above the sun’s surface, can persist for minutes to hours. The loops usually grow and evolve slowly but sometimes can abruptly blast a tremendous amount of energy—billions of times stronger than the most powerful nuclear explosion on Earth—into space. This sudden blast of energy is called a solar flare.

Some of the energy in the flare takes the form of charged particles and “hard X-rays,” which are high-energy electromagnetic waves like those used to image bones in a doctor’s office.

The Earth’s own magnetic field and atmosphere act as a shield that protects life on the surface from getting cooked by these torrents of energy, but they have been known to disrupt communications and power grids. They also pose an ongoing threat to spacecraft and astronauts in space.

While the fact that solar flares generate energetic particles and X-ray bursts has long been known, scientists are only starting to piece together the mechanism by which they do so.

Structural similarities between an actual solar flare (top) and one simulated in the Bellan lab (below). Credit: Bellan Lab

Researchers have two options for deciphering how and why the loops form and change. The first is to observe the sun and hope to capture the phenomenon in sufficiently fine detail to yield relevant information. The second is to simulate the loops in a lab. Caltech’s Paul Bellan, professor of applied physics, chose the latter.

In a lab on the first floor of the Thomas J. Watson, Sr., Laboratories of Applied Physics on Caltech’s campus, Bellan built a vacuum chamber with twin electrodes inside. To simulate the phenomenon, he charged a capacitor with enough energy to run the City of Pasadena for a few microseconds, then discharged it through the electrodes to create a miniature solar corona loop.

Each loop lasts about 10 microseconds, and has a length of about 20 centimeters (cm) and a diameter of about 1 cm. But structurally, Bellan’s loops are identical to the real thing, offering he and his colleagues the opportunity to simulate and study them at will.

“Each experiment consumes about as much energy as it takes to run a 100-watt lightbulb for about a minute, and it takes just a couple minutes to charge the capacitor up,” says Bellan, the senior author of a new paper on solar flares that published in Nature Astronomy.

Bellan captures each loop with a camera capable of taking 10 million frames per second, and he then studies the resulting images.

Among the recent discoveries are that solar corona loops do not appear to be a single structure, but rather are composed of fractally braided strands akin to a large rope.

“If you dissect a piece of rope, you see that it’s made up of braids of individual strands,” says Yang Zhang, graduate student and lead author of the Nature Astronomy paper.

“Pull those individual strands apart, and you’ll see that they’re braids of even smaller strands, and so on. Plasma loops appear to work the same way.”

That structure, it turns out, is important to the generation of energetic particles and X-ray bursts associated with solar flares. Plasma is a strong electrical conductor—think of neon signs, which are filled with plasma and light up when electricity passes through.

However, when too much current tries to pass through a solar corona loop, the structure is compromised. The loop develops a kink—a corkscrew-shaped instability—and individual strands start to break. Each new broken strand then dumps strain onto the remaining ones.

“Like an elastic band stretched too tight, the loop gets longer and skinnier until the strands just snap,” says Seth Pree, postdoctoral scholar research associate in applied physics and materials science, and co-author of the Nature Astronomy paper.

Studying the process microsecond by microsecond, the team noted a negative voltage spike associated with an X-ray burst at the exact instant a strand broke. This voltage spike is akin to the pressure drop that builds up at the point of constriction in a water pipe. The electric field from this voltage spike accelerates charged particles to extreme energy, then X-rays are emitted when the energetic particles decelerate.

In addition, Zhang combed through pictures of solar flares and was able to document a kink instability similar to the one created in the lab that was associated with a subsequent X-ray burst.

Next, the team plans to explore how separate plasma loops can merge and reorganize into different configurations. They are interested to learn if there are also energy burst events during this type of interaction.

Written by Robert Perkins

Results from a clinical trial conducted by researchers at the National Institutes of Health (NIH) show that people with low-grade lymphomatoid granulomatosis treated with interferon alfa-2b, a type of immunotherapy, can live for decades after diagnosis.

Lymphomatoid granulomatosis is a rare precancerous condition triggered by Epstein-Barr virus infection. Left untreated, the disease can progress to a high-grade form, which has a poorer prognosis and can quickly turn into an aggressive and fatal B-cell lymphoma.

In the phase 2 trial, led by researchers in the Center for Cancer Research at the National Cancer Institute (NCI), part of NIH, patients treated with interferon alfa-2b lived for a median of about 20 years.

By contrast, past studies reported a median survival of less than two years for people with lymphomatoid granulomatosis.

The findings suggest that immunotherapy can prevent the progression of low-grade disease to high-grade disease. The results were published in Lancet Haematology.

“We have shown in this rare disorder that using a novel immunotherapy-based approach for low-grade disease is effective and improves survival compared with historical treatments such as chemotherapy and corticosteroids,” said Christopher J. Melani, M.D., of NCI’s Center for Cancer Research, who co-led the study.

“I think the results of this study represent a significant contribution to determining the standard-of-care treatment for this rare disease.”

Lymphomatoid granulomatosis causes an overproduction of white blood cells known as B lymphocytes. Patients typically have lesions in the lungs, central nervous system, skin, liver, and kidneys.

Symptoms can include cough, shortness of breath, fever, weight loss, and fatigue. Chemotherapy is currently the standard treatment for people with high-grade disease, but there is no standard treatment for low-grade disease.

“Although lymphomatoid granulomatosis is uncommon, the effects of high-grade disease can be debilitating,” said Jeffrey Cohen, M.D., chief of the Laboratory of Infectious Diseases at the National Institute of Allergy and Infectious Diseases and a co-leader of the study.

“We need better ways to prevent the disease from progressing to this more severe state, such as interferon alfa-2b.”

NIH researchers have been studying lymphomatoid granulomatosis since the 1980s. In the early 1990s, Wyndham Wilson, M.D., Ph.D., also of NCI’s Center for Cancer Research, hypothesized that low-grade disease results from a defective immune response to the Epstein-Barr virus and could therefore be treated with immunotherapy, whereas high-grade disease requires chemotherapy to curb uncontrolled cell growth.

He and his colleagues treated four people with low-grade lymphomatoid granulomatosis with interferon alfa-2b over a 5-year period, and the treatment eradicated all signs of the disease in three of those patients, known as a complete remission.

That study laid the foundation for the phase 2 trial of interferon alfa-2b in lymphomatoid granulomatosis, which has taken 30 years to complete because of the rarity of the disease and the challenges of recruiting enough patients for the study.

“This really illustrates the unique ability of NIH to do a study like this that nobody else could do and no one else ever has done for this particular disease,” said Dr. Wilson, who co-led the study.

The trial included 67 people with lymphomatoid granulomatosis, 37 with low-grade disease and 30 with high-grade disease. In all cases, the participants had not yet been treated for the disease or their disease had not responded to or had returned after other treatments.

During their initial treatment, most of the patients with low-grade disease received subcutaneous injections of interferon alfa-2b three times a week in increasing doses for about one year. Most of the patients with high-grade disease were given six cycles of intravenous chemotherapy every three weeks.

Both groups improved, with the disease disappearing in 27 of 44 patients (61%) treated with interferon alfa-2b, and 8 of 17 patients (47%) treated with chemotherapy.

After their initial treatment, some patients subsequently received the other therapy, called crossover treatment.

Patients with low-grade disease that worsened after immunotherapy were given chemotherapy, whereas patients with high-grade disease that came back after chemotherapy were given interferon alfa-2b. Previous work showed that after high-grade disease is eliminated with chemotherapy, low-grade disease can re-emerge.

The crossover treatments were also effective, with the disease disappearing in 4 of 8 patients (50%) treated with interferon alfa-2b after chemotherapy and 7 of 15 patients (47%) treated with chemotherapy after interferon alfa-2b.  

Median overall survival was 20.6 years for patients treated initially with interferon alfa-2b and 19.8 years for patients who crossed over to receive interferon alfa-2b. Median overall survival was 12.1 years for patients treated initially with chemotherapy and not reached for those who crossed over to receive chemotherapy. 

The most common side effect of interferon alfa-2b treatment was low white blood cell count, and the most common side effects with chemotherapy were low white blood cell count and infection. Serious side effects occurred in only a quarter of the patients treated with interferon alfa-2b, compared with nearly two-thirds of patients treated with chemotherapy.  

Many newer immunotherapies, such as nivolumab, could potentially be used to treat low-grade lymphomatoid granulomatosis and other Epstein-Barr virus–associated disorders and may have fewer side effects.

“The trial of interferon alfa-2b established that immunotherapy improves survival in patients with low-grade lymphomatoid granulomatosis,” Dr. Melani said. “Now we can look into more novel immunotherapies that are easier to tolerate to see if they can improve on the efficacy of our current treatment.” 

Source: NIH

To understand how to get artificial intelligence right, we need to know how it can go wrong, says researcher.

Artificial intelligence is touted as a panacea for almost every computational problem these days, from medical diagnostics to driverless cars to fraud prevention.

But when AI fails, it does so “quite spectacularly,” says Vern Glaser of the Alberta School of Business. In his recent study, “When Algorithms Rule, Values Can Wither,” Glaser explains how AI’s efficiency imperative often subsumes human values, and why the costs can be high.

“If you don’t actively try to think through the value implications, it’s going to end up creating bad outcomes,” he says.

When bots go bad

Glaser cites Microsoft’s Tay as one example of bad outcomes. When the chatbot was introduced on Twitter in 2016, it was revoked within 24 hours after trolls taught it to spew racist language.

Then there was the “robodebt” scandal of 2015, when the Australian government used AI to identify overpayments of unemployment and disability benefits. But the algorithm presumed every discrepancy reflected an overpayment and automatically sent notification letters demanding repayment. The case was forwarded to a debt collector if someone didn’t respond.

By 2019, the program identified over 734,000 overpayments worth two billion Australian dollars (C$1.8 billion).

“The idea was that by eliminating human judgment, which is shaped by biases and personal values, the automated program would make better, fairer and more rational decisions at much lower cost,” says Glaser.

But the human consequences were dire, he says. Parliamentary reviews found “a fundamental lack of procedural fairness” and called the program “incredibly disempowering to those people who had been affected, causing significant emotional trauma, stress and shame,” including at least two suicides.

While AI promises to bring enormous benefits to society, we are now also beginning to see its dark underbelly, says Glaser. In a recent Globe and Mail column, Lawrence Martin points out AI’s dystopian possibilities, including autonomous weapons that can fire without human supervision, cyberattacks, deepfakes and disinformation campaigns. Former Google CEO Eric Schmidt has warned that AI could quite easily be used to construct killer biological weapons.

Glaser roots his analysis in French philosopher Jacques Ellul’s notion of “technique,” offered in his 1954 book The Technological Society, by which the imperatives of efficiency and productivity determine every field of human activity.

“Ellul was very prescient,” says Glaser. “His argument is that when you’re going through this process of technique, you are inherently stripping away values and creating this mechanistic world where your values essentially get reduced to efficiency. 

“It doesn’t matter whether it’s AI or not. AI in many ways is perhaps only the ultimate example of it.”

A principled approach to AI

Glaser suggests adherence to three principles to guard against the “tyranny of technique” in AI. First, recognize that because algorithms are mathematical, they rely on “proxies,” or digital representations of real phenomena.

One way Facebook gauges friendship, for example, is by how many friends a user has, or by the number of likes received on posts from friends.

“Is that really a measure of friendship? It’s a measure of something, but whether it’s actually friendship is another matter,” says Glaser, adding that the intensity, nature, nuance and complexity of human relationships can easily be overlooked.

“When you’re digitizing phenomena, you’re essentially representing something as a number. And when you get this kind of operationalization, it’s easy to forget it’s a stripped-down version of whatever the broader concept is.”

For AI designers, Glaser recommends strategically inserting human interventions into algorithmic decision-making, and creating evaluative systems that account for multiple values.

“There’s a tendency when people implement algorithmic decision-making to do it once and then let it go,” he says, but AI that embodies human values requires vigilant and continuous oversight to prevent its ugly potential from emerging.

In other words, AI simply reflects who we are — at our best and worst. The latter could take over without a good, hard look in the mirror.

“We want to make sure we understand what’s going on, so the AI doesn’t manage us,” he says. “It’s important to keep the dark side in mind. If we can do that, it can be a force for social good.”

Source: University of Alberta

Of the many kinds of stars, asymptotic giant branch (AGB) stars, usually slightly larger and older than our own sun, are known to produce interstellar dust. Dusty AGBs are particularly prominent dust producers, and the light they shine varies widely.

For the first time, a long-period survey has found the variable intensity of dusty AGBs coincides with variations in the amount of dust these stars produce. As this dust can lead to the creation of planets, its study can shed light on our own origins.

You’ve probably heard of the James Webb Space Telescope (JWST) which has been in the news lately. It’s famous for being the largest and most sensitive space telescope designed to observe infrared (IR) light.

But long before the JWST took to the skies, two other IR space telescopes, AKARI and WISE, have been surveying the cosmos, both of which have ended their initial missions, but produced so much valuable data that astronomers are still finding new discoveries with it.

The latest finding from that data by doctoral student Kengo Tachibana from the University of Tokyo’s Institute of Astronomy and his team, could have implications for the study of the origins of life itself.

“We study stars, and IR light from them is a key source of information that helps us unlock their secrets,” said Tachibana.

“Until recently, most IR data was from very short-period surveys due to the lack of advanced dedicated platforms. But missions like AKARI and WISE have allowed us to take longer-period surveys of things. This means we can see how things might change over greater time periods, and what these changes might imply. Lately, we turned our attention to a certain class of star known as asymptotic giant branch stars, which are interesting because they are the main producers of interstellar dust.”

This interstellar dust is not the same stuff that accumulates on your floor when you forget to vacuum for a few days; it’s a name given to heavy elements that disperse from stars and lead to the formation of solid objects including planets.

Although it’s long been known that AGBs, especially dusty AGBs, are the main producers of dust, it’s unknown what the main drivers of dust production are and where we should be looking to find this out.

“Our latest study has pointed us in the right direction,” said Tachibana.

“Thanks to long-period IR observations, we have found that the light from dusty AGBs varies with periods longer than several hundred days. We also found that the spherical shells of dust produced by and then ejected by these stars have concentrations of dust that vary in step with the stars’ changes in luminosity. Of the 169 dusty AGBs surveyed, no matter their variability period, the concentrations of dust around them would coincide. So, we’re certain these are connected.”

Finding a connection between the concentration of dust and the variability of stars’ brightness is just the first step in this investigation, however.

Now the team wishes to explore the possible physical mechanisms behind dust production. For this, they intend to continuously monitor various AGB stars for many years. The University of Tokyo is nearing completion of a large ground-based telescope project, the University of Tokyo Atacama Observatory, in Chile, dedicated to making infrared observations.

Source: University of Tokyo

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A new way of using 3D printing to create infection-fighting materials for use as medical implants has been revealed in a new research paper.

Engineers at the University of Bath, working with colleagues at the University of Ulster, have for the first time successfully created a new kind of ferroelectric composite material with antimicrobial properties using a novel multi-material 3D printing process.

They say the use of electrically responsive ferroelectric materials gives the implants infection-fighting properties, making them ideal for biomedical applications, such as heart valves, stents, and bone implants reducing the risk of infection for patients.

While commonplace, all biomedical implants pose some level of risk as materials can carry surface bio-contaminants that can lead to infection. Reducing this risk could be beneficial both to patients in the form of improved outcomes, and to healthcare providers thanks to reduced costs incurred by ongoing treatment.

The team has previously used this 3D printing technique for the fabrication of three-dimensional scaffolds for bone tissue engineering.

Dr Hamideh Khanbareh, a lecturer in materials and structures in Bath’s Department of Mechanical Engineering, is lead author of the research. She says that the development has the scope for wide-ranging applications.

She said: “Biomedical implants that can fight infection or dangerous bacteria such as E. coli could present significant benefits to patients and to healthcare providers.

“Our research indicates that the ferroelectric composite materials we have created have a great potential as antimicrobial materials and surfaces. This is a potentially game-changing development that we would be keen to develop further through collaboration with medical researchers or healthcare providers.”

The innovation comes thanks to ferroelectricity, a characteristic of certain polar materials that generate electrical surface charge in response to a change in mechanical energy or temperature. In ferroelectric films and implants, this electrical charge leads to the formation of free radicals known as reactive oxygen species (ROS), which selectively eradicate bacteria.

This comes about through the micro-electrolysis of water molecules on a surface of polarised ferroelectric composite material.

The composite material used to harness this phenomenon is made by embedding ferroelectric barium calcium zirconate titanate (BCZT) micro-particles in polycaprolactone (PCL) a biodegradable polymer widely used in biomedical applications. The mixture of the ferroelectric particles and polymer is then fed into a 3D bioprinter to create a specific porous ‘scaffold’ shape designed to have a high surface area to promote ROS formation.

Testing showed that even when contaminated with high concentrations of aggressive E. coli bacteria, the composite can completely eradicate the bacteria cells without external intervention, killing 70% within just 15 minutes.

Source: University of Bath

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The official date is set: the Russian aircraft carrier “Admiral Kuznetsov” should be fully repaired by 2024. But even if technical works follow the schedule, assembling and training a new crew for this ship will certainly not happen quickly.

“Admiral Kuznetsov” was designed to have 1,900 technical personnel onboard. The new crew should consist of 1,500 people, and such a reduction is explained by the fact that many of the internal systems will be automated and therefore will require less maintenance.

Still, a 1,500-large crew is not a simple thing to prepare, because most of these servicemen will need to undergo very specialized and long training before the vessel will be ready to perform at least basic tasks. Also, due to the ongoing Russian invasion of Ukraine, finding the necessary crew members will not be a simple task.

The repair and overhaul of “Admiral Kuznetsov” have been underway for 6 years. After the ship was stationed at the repair facility, the former crew was disbanded.

Of course, some operations onboard an aircraft carrier are closely similar to those in other types of military ships. Nevertheless, every aircraft carrier has its own specifics, including the fact that the crew must be 100% capable of maintaining aircraft and aviation equipment.

“Even if there are 1500 suitable sailors, their training and familiarization [with the aircraft carrier] will take months, since the Kuznetsov is the largest surface ship in Russia. Even the old team would find it difficult to learn how to properly operate with newly installed equipment. An improperly trained team can lead to major accidents,” commented Russian Navy expert Matus Smutny.

In a similar way, pilots of naval fighter jets Su-33 and MiG-29KR will need to complete additional training after 7 years spent without regular practice at sea.

Previously, Ukrainian military intelligence reported that the ship suffered from significant hull corrosion which is extremely difficult to repair.

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