The Xiaomi Smart Band 9 seems, on first impressions, even better than its predecessor. It boasts up to 21 days of battery life, a brighter 1.62-inch AMOLED display and a more accurate heart rate sensor. Moreover, it features more in-depth sleep tracking features and a whopping 150 sports modes. The cherry on top? It costs only $63.

Xiaomi Smart Band 9 review

Xiaomi Smart Band 9: Design

• Ultra-light and discreet-looking
• Silicone straps may slip off the wrist during sleep
• Can be attached to a running clip (sold separately)

Design-wise, the Xiaomi Smart Band 9 does not stray far from its predecessors. Weighing just half an ounce (15.8 grams) and measuring only 0.85 inches (21.6 millimeters) in width, it is only slightly bigger than its younger siblings. We liked this exceptionally light and compact design. The Smart Band 9 never got in the way of our clothes or exercise equipment, and it felt like a much-needed change after all the bulky smartwatches we tested beforehand.

Following the tried and tested formula, this Xiaomi model also features straps that can be detached with a quick-release mechanism. This was a big plus point for us. The default silicone straps turned out to be somewhat unreliable in our tests: they felt flimsy and uncomfortable to wear for the most part, and on at least two separate occasions they slipped off our wrist during sleep. We were not fond of the band's dull pinkish color, either, and its silicone coating seemed to easily attract dirt.

Interestingly, the Xiaomi Smart Band 9 can also be inserted into a running clip. This little contraption allows you to attach the watch to your running shoe so you can track a range of performance metrics, from running cadence and stride length to ground contact time ratio — and it costs less than $12. For runners on a tight budget, this is a fabulous solution.

Xiaomi Smart Band 9: Display

• Bright, easy-to-read AMOLED display
• Relatively resilient to scuffs and scratches
• Plenty of watch faces to choose from

The Xiaomi Smart Band 9 has a relatively small 1.62-inch display, but we did not find it particularly difficult to navigate. Given our underwhelming experience with the display on the Smart Band 7, we were pleasantly surprised by how responsive and easy-to-read this one was, even when we tried to operate it with wet hands or under direct sunlight.

We also liked how it looked. The display in the Xiaomi Smart Band 9 is crisp and colorful and can be customized with over 200 different watch faces. And if that is not enough, you can even use photos from your gallery to put on your screen.

The display seemed surprisingly durable, too. The AMOLED glass did not scratch or scuff during our extensive testing, even though we must have accidentally bumped our watch at least a dozen times. It is refreshing to see such resilience in a fitness tracker costing less than $70.

Xiaomi Smart Band 9: Features

• Advanced health-tracking features
• Over 150 sports modes
• No built-in GPS tracking (it runs off the phone signal)

The Xiaomi Smart Band 9 impressed us with its robust health-tracking features. This humble-looking watch can track your steps, heart rate, oxygen saturation, sleep quality, stress levels, menstrual cycle and more, making it a surprisingly comprehensive tool for monitoring your energy levels and post-exercise recovery.

Speaking of exercise, the Xiaomi Smart Band 9 can track over 150 activities, from outdoor hiking and cycling to dance and weightlifting. We would not recommend it for competitive swimming or diving, though — it has only a 5ATM water resistance rating.

On the other hand, the Xiaomi Smart Band 9 does not have any major smartwatch features or built-in navigation tools like GPS. Sure, it can update you on the weather forecast or receive phone notifications, and it can use the phone's mobile signal to track your location, but that is pretty much it. The Smart Band 9 is nothing like the high-end Garmin models, but then its ultra-affordable price fully reflects that.

Xiaomi Smart Band 9: Performance

• Three weeks of battery life
• Patchy app connectivity
• Imprecise heart rate measurements during intense exercise

Performance is where the low price point of this watch shows. True, the Xiaomi Smart Band 9 easily lasts three weeks on a single charge — in fact, we managed to get nearly a month of battery life in our tests — but its app connectivity and tracking precision leave much to be desired.

The Xiaomi Smart Band 9 was slow to set up, and it took us several attempts to pair our watch with the Mi Fitness app. Once we managed to get everything up and running, we kept experiencing some minor yet annoying connectivity issues. On several occasions, the app did not record our workouts or sleep properly, and it often took considerable time to sync our devices.

We were also underwhelmed by the accuracy of the Smart Band 9’s heart rate sensor. During one workout, we wore our watch alongside a Polar H9 chest-strap heart rate monitor, and found significant discrepancies between the readings: during intense exercise, the heart rate values differed by as much as 20 beats per minute. In all fairness, these differences were far less pronounced at rest. Therefore we would not recommend the Xiaomi Smart band 9 for tracking lung-busting activities, but it could still do a relatively good job during sleep and low- to moderate-intensity workouts.

Xiaomi Smart Band 9: User reviews

Amazon's customer reviews gave the Xiaomi Smart Band 9 a 4.3 out of 5 stars rating, with nearly two-thirds of users giving it a full five stars. Positive reviews praised this fitness tracker for its long battery life, ease of use and good value for money. As one user said, "It's just as accurate (if not more so) than the Fitbit and colorful. The settings are easy to get to, and I'm pretty satisfied with the results and tracking for sleep."

Negative reviews often revolved around limited functionality and poor tracking accuracy. As one user commented, "Features for this product are very basic, minimal. There's no GPS use during your workouts, so you can't track where you have been and your pace. This product has a lot of potential if developed properly. Fitness enthusiasts may not like this product as much as Fitbit or Garmin."

Should you buy the Xiaomi Smart Band 9?

✅ Buy it if: You are a fitness beginner in search of an entry-level tracker, or a seasoned gym-goer on a tight budget. The Xiaomi Smart Band 9 offers an ultra-light and compact design, heaps of advanced health-tracking features and an impressively long battery life — all for less than $70.

❌ Don't buy it if: You want a fitness tracker that delivers precise heart rate measurements and GPS readings. Experienced exercisers and outdoor enthusiasts may be disappointed by the limited functionality of the Xiaomi Smart Band 9.

If Xiaomi Smart Band 9 is not for you

If you want good value for money, you can't go wrong with the Fitbit Inspire 3. For less than $100, this colorful fitness tracker offers excellent health tracking features, up to 10 days of battery life and a lightweight design. However, it does not feature GPS.

The Garmin Vivosmart 5 is another great alternative to the Xiaomi Smart Band 9. It is durable, jam-packed with tracking features and comfortable to wear. However, it costs nearly $150.

If you would rather invest in a smartwatch, check out the Amazfit Bip 3 Pro. This well-crafted fitness tracker allows you to control some of the features of your phone from your wrist, and comes with built-in Alexa voice control. At $69.99, it also price-matches the Xiaomi Smart Band 9.

Xiaomi Smart Band 9: How we tested

We spent over two months trying and testing the Xiaomi Smart Band 9, looking at its design, features, battery life, connectivity with third-party devices and ease of use. We wore it during the day, while sleeping and when doing a range of gym-based workouts, from high-intensity circuit classes to weightlifting. Finally, we assessed the accuracy of our Xiaomi Smart Band 9 by comparing its heart rate measurements with the data we obtained using a Polar H9 chest-strap heart rate monitor.

Following the inspection, the FDA sent Tom's of Maine a warning letter, which was posted publicly Tuesday (Nov. 19). The letter notes that inspectors observed "significant violations of Current Good Manufacturing Practice regulations" at the facility in Sanford, Maine.

One issue was that inspectors found a microbe called Pseudomonas aeruginosa in water samples used to rinse off equipment and to make toothpaste — specifically, Tom's Simply White Clean Mint Paste. The bacteria can cause a range of infections and is a particular problem in health care settings, in part because it can often be resistant to antibiotics.

Another microbe, called Ralstonia insidiosa, was also found in many water samples. This bacterial species can infect humans, but it does so infrequently.

Related: 39 sickened, 15 hospitalized in E. coli outbreak linked to organic carrots

In addition, Paracoccus yeei was found in a specific batch of Wicked Cool! Anticavity Toothpaste. This is another microbe that infects people "opportunistically." On the rare occasion it causes illness, it's most often seen in people with weakened immune systems.

In addition to these water-quality issues, an inspector found a black-mold-like substance in two damp areas in the facility. "The black substance was within one foot of stainless-steel pails and other product-contact equipment used for OTC [over-the-counter] drug production," the letter states.

In light of these and other findings, the FDA has requested an assessment of the company's manufacturing operations, along with a risk assessment of what could happen if any products were to be sold with "potentially objectionable contamination." The agency has requested that Tom's of Maine specify how the company will respond to that risk assessment and improve its water systems, facility management and cleaning procedures.

The FDA's inspection took place in May, and Tom's of Maine responded to its initial results in June. The FDA's latest letter declares that the company's June response was "inadequate," so the agency is calling for further action.

Tom's of Maine, which is owned by Colgate-Palmolive, has released the following statement to news outlets, including CNN:

"We're working with the FDA and are remedying the issues raised in their May inspection of the Tom's manufacturing plant in Sanford, Maine. We have always tested finished goods before they leave our control, and we remain fully confident in the safety and quality of the toothpaste we make."

"In addition," the statement continues, "we have engaged water specialists to evaluate our systems at Sanford, have implemented additional safeguards to ensure compliance with FDA standards, and our water testing shows no issues. We are also making capital investments as part of an ongoing, significant upgrade of the Sanford plant's water system. Tom's is committed to making safe and effective natural products for our consumers, and to maintaining the trust in our brand."

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Scientists with the Human Cell Atlas (HCA), an international research consortium, have profiled 100 million cells from more than 10,000 people around the world. Working in over 100 countries, the researchers aim to pinpoint similarities and differences in the cells of people from different demographics and genetic backgrounds.

By 2026, the team plans to unveil an atlas of the whole human body that details the location, identity and function of each cell at different stages of life. That atlas will just be a first draft; later iterations could include data from billions of human cells, the scientists project.

Now, HCA scientists have just dropped more than 40 papers that will aid in the construction of the groundbreaking first draft of their atlas. The research trove, published Wednesday (Nov. 20) in several Nature journals, charts cells in many organs and organ systems — including the lungs, brain and skin — and describes the advanced computational tools needed to crunch all those data.

Related: Most detailed human brain map ever contains 3,300 cell types

Aviv Regev, a founding co-chair of the HCA, compared the advance to leaps in traditional cartography. Imagine going from having only 15th-century maps of the world to having Google Maps, complete with detailed topographies, street views and dynamic traffic patterns.

"So that is the leap that we have done — moving from maps that look as crude as that to maps that are the resolution of the Google Map," Regev said at a news conference Tuesday (Nov. 19). "But we still have work to do."

The new research includes a detailed map of the digestive tract, running from the esophagus to the colon. The researchers mapped a healthy digestive tract based on 1.1 million cells sampled from nearly 190 people. They also compiled data from people with different gastrointestinal conditions, including ulcerative colitis and Crohn's disease. Through this work, they uncovered a type of cell that seems to contribute to the inflammation in these diseases, likely by summoning immune cells.

"Intestinal inflammation can cause cells to undergo metaplasia, a shift from one cell type to another," Itai Yanai, scientific director of the Applied Bioinformatics Laboratories at NYU Langone Health, wrote in a commentary. With data from both healthy and diseased guts, the researchers were able to pinpoint which stem cells gave rise to the "metaplastic" cells, Yanai said. After transforming, the metaplastic cells then spurred more inflammation, the research suggested.

In other papers, researchers opened a window into early human development, revealing how the placenta develops and the skeleton starts to form in the first trimester of pregnancy. The latter study revealed never-before-seen states that cells enter as they prepare to form the skull. The researchers also investigated genes that might be involved in craniosynostosis, a birth defect in which the soft spots of the skull fuse too soon.

Other papers focused on "organoids," miniature versions of human organs grown in the lab. One looked at brain organoids, which mimic developing brains. Different labs use various strategies to grow organoids, but that raises questions about which method produces the best model — which brain organoid best mimics an actual brain? The scientists compared maps of human brains to those of organoids, finding that, at least up to the second trimester, the organoids match fetal brains fairly closely. Open questions remain about the third trimester.

Related: Scientists launch amazing 'atlas' of embryos, showing how cells move and develop through time

Another lab ran a similar study looking at skin organoids, to see how closely they resembled real skin.

The atlas helps researchers come up with "better recipes" for organoids, Muzlifah Haniffa, a member of the HCA organizing committee, said at the news conference.

But "the information kind of flows both ways," Sarah Teichmann, an HCA co-chair, added, because the organoids also reveal subtle details of what's happening inside the body. Scientists can "poke the cells, perturb the cells" in ways that wouldn't be possible in human subjects, she said. Thus, making true-to-life organoids can help reveal how diseases arise and which drugs might effectively treat them.

Taken together, the more than three dozen HCA papers represent a major step forward. Meanwhile, data previously published by the consortium have already fueled new discoveries: Work published in 2020 helped reveal unexpected tissues that were vulnerable to COVID-19, and a map of the human lung revealed a new type of cell — the ionocyte — that may play a key role in cystic fibrosis.

"Collectively, the atlases have the potential to constitute a resource that others might be inspired to explore and compare with other biological contexts, such as different species and rare diseases," Yanai wrote. "Researchers might then discover aspects of the human body that cannot yet be imagined."

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But which air purifiers should you buy right now? We've been testing and reviewing air purifiers for years so we know a thing or two about them, like which models are the best air purifiers for allergies. We track prices daily, so if the price changes we know by how much and whether it's been better before. Rest assured, if there's an air purifier deal to be had you can find it here, let us do the legwork for you and save right now with the very best Black Friday air purifier deals.

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Best under $100

Best under $300

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Check out our other guides to the best air purifiers, air purifiers for allergies, the best telescopes, microscopes for students, binoculars, rowing machines, electric toothbrushes and more.

The symptoms: The man's skin turned yellow and he became lethargic and nauseated. He also developed diarrhea and started vomiting blood before being brought to the emergency room.

What happened next: Doctors found that several of the man's organs had begun to fail, and his blood tested positive for Psilocybe cubensis, a fungus containing the psychoactive compound psilocybin.

The diagnosis: Prior to developing symptoms, the man had boiled "magic mushrooms" into a tea, which he then filtered through cotton and ultimately injected into his body. The patient was diagnosed with a fungal infection of the blood, as well as a bacterial infection. These infections led to multisystem organ failure and acute respiratory syndrome, in which fluid builds up in the air sacs of the lungs.

The treatment: The patient received antibiotics and antifungal drugs. He was also placed on a ventilator, which helped him breathe while in the hospital. After being discharged, he continued taking antibiotics and antifungal drugs as part of a long-term therapy.

What makes the case unique: Typically, when used recreationally, magic mushrooms are made into a tea for drinking — not injecting — or the fungi are eaten in raw, dried or powdered forms. Sometimes, they're incorporated into candies. In medical settings, the compound psilocybin may be administered via a pill or an intravenous injection, but this type of medical-grade, purified psilocybin has no fungi in it.

In this case, the patient developed a dangerous infection after introducing fungi into his bloodstream, highlighting the dangers of this route of administration. The patient did this in an attempt to relieve symptoms of bipolar disorder and opioid dependence.

As scientists study the potential clinical uses of psilocybin and other psychedelics, it's important for the public to be informed about the "dangers attendant to the use of this, and other drugs, in ways other than they are prescribed," the man's doctors wrote in a report.

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The Dreo 713S has all the bells and whistles you might expect in a smart appliance these days, from a colorful touchscreen to a connected app and voice control. Other specs are no less promising. As an ultrasonic humidifier, it increases relative humidity by dispersing tiny water droplets into the air, and since the Dreo 713S releases both cool and warm mist, it can be used all year round. Moreover, this humidifier has a built-in moisture sensor and an auto mode that allows you to keep the indoor humidity exactly how you like it. It even has a dual-aroma pad tray that allows you to switch between two fragrances should you wish.

For $89.99, the Dreo 713S seems to offer good value for money. But does it have what it takes to earn a prime spot in our guide to the best humidifiers?

Dreo 713S Smart Humidifier review

Dreo 713S Smart Humidifier: Design

• Looks great, but its narrow shape requires space to accommodate it
• The water tank is easy to refill and move around
• Cleaning the unit can be complex and time-consuming

The first thing we noticed about the Dreo 713S was its somewhat odd shape. Most humidifiers are cylindrical or otherwise “pudgy”. This one, on the other hand, is unusually slim. The Dreo 713S measures nearly 14-inches (36 cm) in height and 12-inches (29 cm) in depth — but just 6 inches (15.6 cm) in width. This narrow shape has its pros and cons.

For example, it makes the humidifier easy to grab hold of and move around. At the same time, it requires quite a lot of space to accommodate it. According to the manual, the Dreo 713S can't be placed on the floor or carpet, and its nozzle needs to be at least 12 inches away from the wall. This means you have to put the humidifier vertically in relation to a wall. It may not fit on a narrow shelf or small bedside table, for example.

The Dreo 713S looks great nonetheless. Unlike most humidifiers, it does not have buttons and other protruding controls. Instead, it features a crisp and colorful touchscreen display. The Dreo 713S is sleek, modern and easy on the eye — and that is something we do not say often about humidifiers.

We liked its water tank, too. Thanks to its 1.58 gallon (6 L) capacity, we did not need to refill it a lot. Of course, this also means it inevitably gets heavy when full, but its built-in handrail made it relatively easy to detach the water tank from the base and refill it without causing spillages. The tank is also semi-transparent, which helps to keep an eye on the water levels.

However, there are two downsides. First, the unit itself can be a hassle to maintain. While the water tank is relatively quick and easy to clean, other parts of the Dreo 713S, such as the mist tube or noise silencer, require a more complex cleaning procedure. Given that weekly cleaning is recommended, some people may find this impractical.

Moreover, the Dreo 713S lacks some durability. This humidifier is made predominantly of plastic, making it light but somewhat feeble — we would not bet on it surviving a fall from height, for example. In all fairness, though, we had no issues with the Dreo 713S during testing.

Dreo 713S Smart Humidifier: Features

• Warm and cool mist at three output levels
• Humidistat and auto mode
• Plenty of smart features

The Dreo 713S disperses warm and cool mist, both of which can be manually adjusted across three output levels. Thanks to a built-in humidistat (a sensor that continuously measures relative humidity), it also has an auto mode in which the mist output is automatically adjusted to a chosen level. Target humidity can be set between 30% and 90% at 5% intervals.

The Dreo 713S also comes with a 12-hour timer button, brightness control button, low water indicator and a humidity indicator light — which turns yellow when the humidity level drops below 30%, green when it is between 31% and 60%, and blue when the humidity rises above 61%.

The Dreo app comes with more features, such as a cleaning reminder, setting schedules or enabling voice control assistants. The app will also store the humidity measurements from the past 30 days. This easy-to-understand graph can be particularly useful for identifying the potential causes of drops and spikes in relative humidity over time.

Dreo 713S Smart Humidifier: Performance

• Fast and efficient at increasing relative humidity
• Quiet when in use
• The humidistat may be slightly imprecise

The Dreo 713S impressed us with its efficient and long-lasting humidification — especially in auto mode. This smart humidifier did a good job at keeping the target humidity by adjusting the mist output accordingly and switching itself off once the target was achieved. This helped prevent damp build-up, and a full tank could last for days on end (or at least, it could in our mild climate).

The Dreo 713S was also near-silent. When we measured its noise levels with a Sound Meter decibel-counting app, we did not get a reading higher than 14 decibels — which is about as loud as a whisper or leaves rustling in the wind.

We tested its humidifying capabilities and the accuracy of its built-in humidistat using a Perfect Prime air particle counter, an industry-grade device that provides precise measurements of air pollution and relative humidity. We put the Dreo 713S in a closed, medium-sized room and ran it on the highest cold mist output for two hours, making note of changes to relative humidity. After an hour, the relative humidity increased from 59% to 72%, and after two hours it rose to a whopping 83%. However, we also noted that Dreo's built-in humidistat tended to underestimate the readings by roughly 2 to 4%. This is not a huge discrepancy — but significant enough for those who need precise humidity control.

Then, we repeated the test on the highest warm mist setting. We obtained similar results in relative humidity, but understandably, after two hours of testing the room felt much warmer than when we started. We also noted a much higher spike in our electricity usage. The warm mist in the Dreo 713S is quite a powerful feature, so if anything, we would suggest starting from a low output first and going up from there. At the same time, this means the humidifier can be handy during cold winter months.

Dreo 713S Smart Humidifier: User reviews

The Dreo 713S scores 4.4 out of 5 stars at Amazon. Users praised this humidifier for its sleek design, intuitive controls, easy-to-clean water tank and most importantly, the ability to quickly raise humidity levels without making hardly any noise.

One user said, "I had a Levoit humidifier but it made the carpet wet even from up on a table and went through a gallon of water in just a few hours. This one is SO much better! It brought my little room with my cello up to target humidity very quickly using a mere fraction of water. Plus it looks sleek and the indicator light is really helpful to gauge humidity at a glance just by color. Also, the top fill is so much easier than the bottom fill Levoit. Super quiet too and holds an ample 1.5 gallons. And the carpet is dry."

Negative remarks tended to revolve around defective units and overall value for money. Several users also complained about leakages from the unit's base. One review stated: "I was pretty happy, until I woke up to the sound of dripping water coming from the top of my dresser, twice within the same week. Unfortunately, I experienced the same issue as other reviewers. There is a design flaw that allows for the base to overfill, and flow out onto your furniture. What good is a $80 unit if it will ruin a $1,000 dresser?"

Should you buy the Dreo 713S Smart Humidifier?

✅ Buy it if: You are looking for a user-friendly smart humidifier that can be used all year round. The Dreo 713S releases both warm and cool mist, and its output can be customized across three levels of intensity. This smart humidifier can also automatically adjust its mist settings to maintain target humidity, and its wide range of features adds to its overall functionality.

❌ Don't buy it if: You need something small and easy to maintain. The Dreo 713S requires a lot of space to accommodate it, and quite some time and effort to clean it.

If Dreo 713S Smart Humidifier isn't for you

The Levoit LV600HH is a great alternative to the Dreo 713S. This humidifier also offers cool and warm mist, an auto mode and a built-in humidity sensor, and costs just 10 dollars more. However, we also think its humidistat is a tad too sensitive.

If smart features are your priority, check out the Dyson AM10 Humidifier. This appliance can be controlled remotely, and it comes with a built-in fan, UV light sanitizer and the ability to set target humidity. The caveat? It costs a whopping $599.

But if you want something unique, consider the Homedics TotalComfort Deluxe Ultrasonic Humidifier. It features a modern, quirky design, intuitive controls and programmable humidity levels — but at $119.99, it is slightly more expensive than the Dreo 713S.

Dreo 713S Smart Humidifier: How we tested

We tested the Dreo 713S Smart Humidifier for a week, looking at its design, features, performance, ease of use and maintenance. We also tested its humidifying capabilities and the accuracy of its built-in humidistat using an industry-grade Perfect Prime air particle counter. We placed the Dreo 713S in a closed, medium-sized room and ran it on the highest cold mist output for two hours, making note of changes to relative humidity. Then, we repeated the test on the highest warm mist setting. We also measured how loud this humidifier was with a Sound Meter decibel-counting app.

On Saturday (Nov. 16), the U.S. Food and Drug Administration (FDA) announced that Grimmway Farms, headquartered in Bakersfield, California, had recalled certain brands of its organic whole carrots and organic baby carrots. These carrots should no longer be available in grocery stores but may still be in consumers' fridges or freezers, the statement noted. The details of the brands and bag sizes that have been recalled can be found in the FDA's announcement.

These carrots have been tied to an outbreak of E. coli, or Escherichia coli, a bacterial infection that can be severe, or even fatal, for young children, older people and people with weakened immune systems. As of Nov. 17, 39 people in 18 states have been infected by the same strain of E. coli, the Centers for Disease Control and Prevention (CDC) reported.

Fifteen of those people have been hospitalized, and one in California died.

The total number of people affected by the outbreak is likely higher, the CDC said. That's because the infection takes several days to manifest, and it takes weeks for officials to confirm that a case is tied to a given outbreak. Additionally, milder cases of infection likely go unreported.

Related: 'Vampire' bacteria thirst for human blood — and cause deadly infections as they feed

The type of bacteria tied to the outbreak is known as E. coli O121:H19. These microbes release a toxin that can damage the lining of the intestines, causing bloody diarrhea. Other symptoms include stomach cramps, fever, nausea and vomiting. In really severe cases, the infection can lead to hemolytic uremic syndrome (HUS), in which blood cells and the kidneys are damaged, potentially leading to kidney failure and death.

No one in the ongoing outbreak has developed HUS, the CDC noted. But, as evidenced by the fatality in California, E. coli can be deadly even if a person doesn't develop HUS.

Health officials interviewed most of the people confirmed to have been sickened in the outbreak and found that a large percentage reported eating carrots before falling ill. They reported buying different brands of carrots from different stores, but investigators were able to identify Grimmway Farms as the common supplier across many of the cases.

"FDA is working with Grimmway Farms to determine the source of contamination, whether additional products are affected, and what retailers received the recalled carrots," the CDC noted.

In the meantime, health officials advise consumers to check their fridges and freezers for the recalled carrots and throw away any they find. Wash any items or surfaces that may have touched the recalled carrots, using hot, soapy water or a dishwasher.

Contact a health care provider if any severe symptoms of E. coli infection develop, such as high fever, vomiting or bloody diarrhea. Symptoms typically arise within three or four days of E. coli exposure, but they could emerge up to 10 days later.

The states where people have gotten sick so far include Arkansas, California, Colorado, Massachusetts, Michigan, Minnesota, Montana, North Carolina, New Jersey, New York, Ohio, Oregon, Pennsylvania, South Carolina, Texas, Vermont, Washington and Wyoming.

Ever wonder why some people build muscle more easily than others or why freckles come out in the sun? Send us your questions about how the human body works to community@livescience.com with the subject line "Health Desk Q," and you may see your question answered on the website!

The trial used a form of chimeric antigen receptor (CAR) T cell therapy, which has become a mainstay treatment for blood cancers, like leukemia.

Only a few patients were included in this initial trial, and the trial was short — so it's too early to say whether this treatment works over the long term. But markers of disease in the patients' blood suggest the autoimmune processes had been shut down, at least for now.

If this therapy proves effective in larger, longer follow-up trials, it could change the way autoimmune diseases are treated.

"I think it will change the standard of care in lupus," said study co-author Dr. Georg Schett, vice president of research and head of the Department of Internal Medicine at Friedrich-Alexander University Erlangen-Nürnberg in Germany.

Related: In a 1st, scientists use designer immune cells to send an autoimmune disease into remission

Schett presented the trial's findings Sunday (Nov. 17) at the American College of Rheumatology meeting in Washington, D.C. The findings have not yet been peer-reviewed or published in a scientific journal.

Typically, lupus patients must take immune-suppressing treatments for life; by comparison, the new therapy requires only a single infusion. "If you have a single infusion and you don't need anything anymore, you're free," Schett told Live Science.

The trial was a "basket study," so named because patients with different conditions are tossed into one basket and all given the same treatment. In this case, the team treated 15 patients — 11 with severe lupus, three with systemic sclerosis and one with idiopathic inflammatory myopathies.

These autoimmune diseases have different symptoms, such as muscle weakness, thickened skin and kidney failure. However, all of them are caused by a subset of the body's B cells, a type of immune cell, going rogue and cranking out antibodies that target a person's tissue for destruction.

Normally, B cells work alongside T cells, which help call the B cells into action and can also kill cells directly. The most common type of CAR T cell therapy works by genetically tweaking a patient's T cells so they can spot and kill cancerous B cells more effectively.

In the new trial, the team gave each of the 15 patients with severe autoimmune disease one infusion of these designer immune cells. The CAR T cells then hunted and eliminated all of the body's B cells — both healthy ones and those driving autoimmune disease.

Seven days after this treatment, the designer cells had eliminated all of the B cells circulating in the patients' blood streams. By two months out, no B cells remained in any tissue, Schett said.

However, by three months after the infusion, the body had completely replenished the B cell population — and the B cells seemed to be healthy.

"It's like a reset button on a computer," Schett said. "You just take everything away, you shut it down, and then it reboots in a normal way and it doesn't have these [autoimmune] B cells anymore."

The trial was designed to test the safety of the new treatment, not how well it treats autoimmune disease. But "surrogate" markers of disease, such as the levels of tissue-targeting antibodies and T cells in the blood, appeared to be normalized.

In addition, all of the patients have been off their traditional treatments since their infusions — the longest for 11 months now.

One of the biggest worries with CAR T therapy used in cancer is "cytokine release syndrome," in which the body erupts into severe inflammation after treatment. That reaction did not seem to be a big issue here, the researchers reported.

As a follow-up, the team will evaluate the drug's efficacy in larger trials. They will also continue to follow these initial patients for longer periods, Schett said.

To develop new antibiotics, researchers typically identify the genes that make bacteria resistant. Through laboratory experiments, they observe how bacteria respond to different antibiotics and look for mutations in the genetic makeup of resistant strains that allow them to survive.

While effective, this method can be time-consuming and may not always capture the full picture of how bacteria become resistant. For example, changes in how genes work that don’t involve mutations can still influence resistance. Bacteria can also exchange resistance genes between each other, which may not be detected if only focusing on mutations within a single strain.

My colleagues and I developed a new approach to identify E. coli resistance genes by computer modeling, allowing us to design new compounds that can block these genes and make existing treatments more effective.

Related: Scientists have found a secret 'switch' that lets bacteria resist antibiotics — and it's been evading lab tests for decades

Identifying resistance

To predict which genes contribute to resistance, we analyzed the genomes of various E. coli strains to identify genetic patterns and markers associated with resistance. We then used machine learning algorithms trained on existing data to highlight novel genes or mutations shared across resistant strains that might contribute to resistance.

After identifying resistance genes, we designed inhibitors that specifically target and block the proteins these genes produce. By analyzing the structure of the proteins these genes code for, we were able to optimize our inhibitors to strongly bind to these specific proteins.

To reduce the likelihood that bacteria would evolve resistance to these inhibitors, we targeted regions of their genome that code for proteins critical to their survival. By interfering with how bacteria carry out important functions, it makes it more difficult for them to develop mechanisms to compensate. We also prioritized compounds that work differently from existing antibiotics to minimize cross-resistance.

Finally, we tested how effectively our inhibitors could overcome antibiotic resistance in E. coli. We used computer simulations to assess how strongly a number of inhibitors bind to target proteins over time. One inhibitor called hesperidin was able to strongly bind to the three genes in E. coli involved in resistance that we identified, suggesting it may be able to help combat antibiotic-resistant strains.

A global threat

The World Health Organization ranks antimicrobial resistance as one of the top 10 threats to global health. In 2019, bacterial antibiotic resistance killed an estimated 4.95 million people worldwide.

By targeting the specific genes responsible for resistance to existing drugs, our approach could lead to treatments for challenging bacterial infections that are not only more effective but also less likely to contribute to further resistance. It can also help researchers keep up with bacterial threats as they evolve.

Our predictive approach could be adapted to other bacterial strains, allowing for more personalized treatment strategies. In the future, doctors could potentially tailor antibiotic treatments based on the specific genetic makeup of the bacteria causing the infection, potentially leading to better outcomes.

As antibiotic resistance continues to rise globally, our findings may provide a crucial tool in the fight against this threat. Further development is needed before our methods can be used in the clinic. But by staying ahead of bacterial evolution, targeted inhibitors could help preserve the efficacy of existing antibiotics and reduce the spread of resistant strains.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

All of AirDoctor’s air purifiers are equipped with an UltraHEPA filter. This means that they can capture at least 99.99% of airborne particles as small as 0.003 microns in size — 100 times smaller than a regular HEPA filter. AirDoctor air purifiers also have a pre-filter that catches large particles like dust and hair and a dual-action carbon/VOC filter that traps odors and volatile organic compounds. On top of that, their jet fans are deemed to be 30% quieter than the fans used in traditional air purifiers.

Intrigued by these impressive specs, we tested the AirDoctor AD3500, the most popular model in the brand's line-up. Given that this model can cover up to a whopping 1,260 square feet (117 square meters), it has the potential to be our top pick for large rooms and commercial premises.

AirDoctor AD3500 air purifier review

AirDoctor AD3500: Design

• Ultra-light and portable for the unit's size
• Basic, uninspiring design
• Intuitive control panel with dimmable indicator lights

The AirDoctor AD 3500 did not impress us with its appearance. With its rectangular shape and white, glossy surface, we thought it looked more like a mini fridge than an air purifier. However, this ultra-basic design has some advantages. If you do not want your air purifier to draw much attention, the AirDoctor AD 3500 will be right up your street. Its indicator lights can be switched off when needed, and its control panel is very intuitive to use, too.

We also liked its light and portable frame. The AirDoctor's AD3500 weighs 18 pounds (8.16 kg), which is surprisingly little for an air purifier that can cover up to 1,260 square feet (117 square meters). When we first picked it up (which can be easily done thanks to two deep ridges conveniently located on the sides), we even questioned whether we may have received a faulty unit. But no, the AD3500 really is that light. It is a great option if you lack strength or need to move the unit around frequently.

In addition, the AirDoctor air purifier is easy to clean and maintain. It has no deep crevices or awkward protruding elements, and the filters can be replaced in mere seconds thanks to a magnetically attached lid at the front of the unit.

Speaking of replacement filters, they are not cheap. AirDoctor charges a whopping $152.99 for a one-year supply — almost twice as much as most of its direct competitors. This is quite a big downside.

AirDoctor AD3500: Features

• Pre-filter, UltraHEPA filter and carbon/VOC filter
• Optional smart features
• Air particle sensor and auto mode

This air purifier is available in two options: with and without smart features. We tested the basic AirDoctor AD3500 model which has no Wi-Fi connectivity and costs $629.99. The smart-enabled option, the AirDoctor AD3500i, costs $50 more and offers features such as remote control, air quality readings and filter change alerts.

We liked this approach. Some people love high-tech frills, while others do not need or care about them, and it is rare to see a brand that caters to both of these groups simultaneously. Nevertheless, we still think both models are on the expensive side.

The AirDoctor AD3500 is equipped with three filters: a pre-filter to capture large particles like dust and pet hair, a carbon/VOC filter that removes odors and volatile organic compounds (VOCs), and an UltraHEPA filter designed to trap 99.99% of ultra-fine particles down to 0.003 microns in diameter. This air purifier also comes with an ionizer, built-in air particle monitor, auto mode and a timer. It is not the most feature-packed appliance we’ve ever tested, but it has everything you need — except smart features, that is.

AirDoctor AD3500 air purifier: Performance

• Great air-cleaning performance in ambient air tests
• Does an excellent job at removing smoke particles
• Relatively quiet, but its airflow can be disruptive

We were impressed by the performance of the AirDoctor AD3500. This air purifier appeared to do a good job at removing odors and airborne pollutants, making the air in our home tangibly easier to breathe. It was also relatively quiet. When we measured it with a decibel-counting Sound Meter app, we did not get a reading higher than 57 dB — equivalent to the sound levels generated by a refrigerator or a vacuum cleaner.

There is one caveat, though: The airflow in the AD3500 is very powerful. When this air purifier kicks into high gear, it almost resembles a tower fan. If you intend to keep it in your bedroom, you may want to place it at a considerable distance from your bed so it does not disturb your sleep. On the other hand, this strong airflow likely contributed to the excellent results we obtained in our tests using an industry-grade Perfect Prime air particle monitor.

We started with an ambient air test. We put the AirDoctor AD3500 in an enclosed, medium-sized room, took baseline air quality readings, then ran this air purifier on its auto settings for 15 and 30 minutes. The results were impressive. After 15 minutes, the AD3500 removed 85.4% of particles measuring 0.3 microns and 99.99% of pollutants measuring 2.5 microns (no 10-micron particles were detected). After half an hour, these values rose even further — to 91.5% and 100%, respectively. We obtained similar results when we repeated the test in a different room.

We got even better results during our smoke tests. First, we burned 10 matches, then we ran the AD3500 for 15 and 30 minutes on its auto setting. After 15 minutes, our AirDoctor had hoovered up a staggering 98.9% of 0.3-micron particles, 99.95% of particles measuring 2.5 microns, and all the pollutants larger than 10 microns. 15 minutes later, the air quality was comparable to the baseline measurements. When we did the match test on the highest setting, nearly all particles were gone after 15 minutes.

Next, we burned five incense sticks and repeated the procedure. The AirDoctor AD3500 trapped nearly all particles after 15 minutes, and just like in the match test, the air quality after 30 minutes returned to the baseline levels.

All in all, it is rare to see such a well-performing air purifier for under $700. The cherry on top? It is Energy Star-certified.

AirDoctor AD3500 air purifier: User reviews

Amazon's customer reviews gave the AirDoctor AD3500 a 4.7 out of 5 stars rating, with 84% of users giving it a full five stars. Positive reviews often praised this air purifier for its powerful air-cleaning performance, unobtrusive design and quiet jet fans. As one user said, "This one is the best bet for the cost, can clean a fairly large space, and can capture particles even finer than most other purifiers available. Yes, there are better units available, but they're going to cost at least twice as much. This unit outperforms everything else in its price point."

Negative reviews tended to revolve around acrid smells coming from the unit and poor customer service from the company. As one user commented, "I wanted to love this machine. The power to move the air was great but as soon as I opened the front to remove the plastic cover over the charcoal filter a strong chemical odor overtook me. It gave me instant sinus pain."

Should you buy the AirDoctor AD3500 air purifier?

✅ Buy it if: You are looking for a top-quality air purifier for large spaces and commercial premises. The AirDoctor AD3500 is ultra-light, portable and immensely powerful, but won’t put too much strain on the energy bill or make excessive noises. It comes with optional smart features, too.

❌ Don't buy it if: You want an air purifier suitable for small spaces, or are on a tight budget.

If AirDoctor AD3500 is not for you

The stylish Molekule Air Pro is an excellent alternative to the AirDoctor AD3500. Packed to the brim with high-tech features, this thoughtfully designed air purifier covers up to 1,000 square feet (92.9 square meters). However, the Molekule Air Pro is also very noisy, and at nearly $1,000, almost twice as expensive as the AD3500.

If you are looking for something cheaper, check out the Levoit Core 600S. This air purifier takes the top spot in our guide to the best air purifiers thanks to its ease of use, smart features and outstanding air-cleaning performance — and it costs just $299.99. However, it only covers rooms of up to 635 square feet (59 square meters).

Want something better looking? Then the RabbitAir A3 should be on your radar. This beautifully designed air purifier delivers excellent air-cleaning performance at a whisper-quiet level, and it covers up to 1,070 square feet (99 square meters). It does, however, carry a $749.95 price tag.

AirDoctor AD3500 air purifier: How we tested

We spent over two months testing the AirDoctor AD3500, looking at its design, features, day-to-day performance, ease of use and value for money. We also measured how loud this air purifier was on different fan speeds using a Sound Meter decibel-counting app.

Then, we conducted a series of performance tests using a Perfect Prime air particle monitor, a professional-grade device capable of detecting airborne pollutants as small as 0.3 microns. We started with an ambient air quality test: we put the AirDoctor AD3500 in an enclosed, medium-sized room and ran it on auto mode for 30 minutes, taking air quality readings every 15 minutes.

Next, we performed several smoke tests. We burned matches and incense sticks to create different types of heavy pollution, then recorded the changes in air quality readings before and after running the AirDoctor AD3500 for 30 minutes. The smoke tests were conducted on the maximum fan speed and auto settings.