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Best Chromebook Black Friday 2018 deals: Dell, Google, HP, and more

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Thanks to their low price and popularity with schools, Chromebooks remain one of the bright spots in a flagging PC market. No surprise, then, that retailers are offering many Chromebook deals for Black Friday. While some of the sales are for Chrome OS running laptops with smaller screens and minimal specs that cost as little as $99, Chromebooks have evolved to offer bigger displays, 2-in-1 capabilities, and more high-end features as found in Google’s PixelBook. We’ve rounded up those specials below to make it easy for you to find the right deal if you’re planning to buy a Chromebook on Black Friday.

Acer

Costco

Acer Chromebook R11 2-in-1 (Intel Celeron, 4GB RAM, 32GB SSD, 11.6-inch touchsceen): $199.99
Acer 2-in-1 Chromebook with a quad-core processor for $289.99 ($100 off)

Staples

Acer Chromebook CB3-431-C5FM (Intel Celeron, 4GB RAM, 32GB SSD, 14-inch full HD display): $199.99 ($100 off)
Acer Chromebook CB5-312T 2-in-1 (MediaTek processor, 4GB RAM, 32GB SSD, 13.3-inch full HD touchscreen): $309.99

Dell

Dell Online Store

Dell Inspiron Chromebook 11 for $199.99

Google

Best Buy

Google Pixelbook for $699 ($300 off )

Google Store

Pixelbooks are $300 off, starting at $699

HP

Costco

14-inch HP Chromebook with Intel Celeron processor for $199.99

HP Online Store

Chromebook 11-v010nr (Celeron N3060, 4GB RAM, 16GB SSD, 11.6-inch display): $179.99
Chromebook 14-ca060NR (Celeron N3350, 4GB, 32GB SSD, 14-inch display): $219.99
Chromebook x360 11-ae010nr 2-in-1 (Celeron N3350, 4GB, 16GB SSD, 11.6-inch touchscreen): $269.99
Chromebook x360 14-da0021nr 2-in-1 (Core i3, 8GB, 64GB SSD, 14-inch touchscreen): $449.99
Chromebook x2 12 2-in-1 (Core m3, 4GB, 32GB SSD, 12.3-inch touchscreen): $549.99

Office Depot/OfficeMax

HP 11.6-inch Chromebook for $129.99 ($90 off)

Target

11.6-inch HP Chromebook for $119.99 ($80 off)
HP Chromebook x360 (Celeron N3350, 4GB, 32GB SSD, 11.6-inch touchscreen): $199.99 ($100 off)

Lenovo

Best Buy

Chromebook MT8173c 2-in-1 (MediaTek processor, 4GB RAM, 32GB SSD, 11.6-inch touchscreen): $179.99

Samsung

Best Buy

11.6-inch Samsung Chromebook with Intel Celeron processor for $9911.6-inch Samsung Chromebook with twice the RAM and storage for $129

Samsung Online Store

Samsung Chromebook Plus V2 2-in-1 (Celeron, 4GB RAM, 32GB SSD, 12.2-inch full HD display): $349.99 ($150 off)
Samsung Chromebook Pro 2-in-1 (Core m3, 4GB RAM, 32GB SSD, 12.3-inch full HD touchscreen): $499.99 ($100 off)

Walmart

Samsung Chromebook 3 with Intel Celeron for $99 ($100 off)

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FDA advisors green-light Pfizer boosters for people 65+ and at-risk groups

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Enlarge / Vials with COVID-19 Vaccine labels showing logos of pharmaceutical company Pfizer and German biotechnology company BioNTech.

A committee of independent advisors for the Food and Drug Administration has voted unanimously (18 to 0) in favor of authorizing a booster dose of the Pfizer/BioNTech COVID-19 vaccine for people aged 65 and older, as well as people at high risk based on an underlying medical condition and/or occupational exposure (e.g., healthcare workers). The booster doses are recommended to be given at least six months after completion of the primary two doses.

If the FDA moves forward with the advisory committee’s recommendation—which it likely will—boosters will be offered to those two groups based on an Emergency Use Authorization.

Prior to voting in favor of authorization for the two groups, the committee rejected the idea of approving boosters for all people ages 16 and up with a resounding vote of 16 to 2 against.

Generally, the committee—Vaccines and Related Biological Products Advisory Committee (VRBPAC)—felt there was simply too little safety data to make an assessment, particularly for young males at highest risk of developing a rare COVID-19 vaccine side effect of inflammation of or around the heart (myocarditis and pericarditis). In addition, the committee felt there was not convincing data that overall vaccine protection from severe disease, hospitalization, and death has waned to the extent that a booster shot is necessary.

“A third dose is likely beneficial,” Ofer Levy, a voting VRBPAC member and infectious disease expert at Harvard, said after voting against boosters for all. “That’s already true for the immunocompromised. It’s likely beneficial, in my opinion, for the elderly and may eventually be indicated for the general population. I just don’t think we’re there yet in terms of the data.”

The votes came after a tumultuous all-day meeting in which advisory committee members seemed to chafe at the expectation that they would green-light boosters for the general population. Last month, the Biden Administration announced ahead of the FDA’s review that it was prepared to roll out boosters for the vaccinated starting the week of September 20. The announcement reportedly prompted frustration and anger inside the regulatory agency, leading two high-ranking vaccine regulators to announce their resignations.

Vaccine effectiveness

One of those resignations was Marian Gruber, the now-outgoing director of the FDA’s Office of Vaccines Research and Review. At the opening of today’s proceedings, she thanked her staff, noting that it was likely her last VRBPAC meeting. In her opening remarks, she emphasized that the decision of whether to approve a booster dose hinges on determining if it’s “safe,” which “involves weighing whether its benefits outweigh its risks.” For younger males, that leaves the tricky question of whether the potentially increased risk of myocarditis/pericarditis would be outweighed by the potential benefits of a third dose, given that younger males are already at lower risk of severe disease than older groups and still appear to have high levels of protection from the two primary doses.

CDC epidemiologist Sara Oliver presented a synthesis of data suggesting that vaccine efficacy against infection has declined over time, but protection against hospitalizations has remained strong. Comparing pre-delta vaccine efficacy in adults aged 18+ to the latest post-delta data, the range of vaccine efficacy against infection fell from 72 to 92 percent pre-delta to a range of 39 to 84 percent post-delta in July. For hospitalization, vaccine efficacy prior to delta ranged from 84 to 97 percent, dropping to a range of 75 to 95 percent in July after delta.

Critically, when the agency’s analyses just looked at older populations rather than all adults together, vaccine effectiveness still appeared strong, with an efficacy of over 88 percent in people aged 75 and above. However, Dr. Oliver noted data from Qatar suggesting that protection from hospitalization declined in people aged 60 and over after 25 weeks from vaccination, though the confidence intervals were extremely wide.

Similarly, experts from Israel presented data suggesting that vaccine efficacy continues to wane over time, with elderly groups seeing less protection against severe disease. Israel is ahead of the US by about three months in getting a large chunk of its population vaccinated. Thus, the country is seen as a bellwether of vaccine effectiveness. In light of data suggesting widespread waning of protection, Israel rolled out a booster shot on July 30 to all those 16 and over, beginning with the elderly. In the time since, Israel data suggests the boosters stymied confirmed cases in people over 60 and provided a more than 10-fold reduction in relative risk of severe disease in that age group. Unfortunately, there hasn’t been enough time since boosters were rolled out to younger males to generate useful data on safety that could inform a decision in the US.

Data concerns

In another presentation at the meeting, statistician Jonathan Sterne of the University of Bristol warned against taking real-world vaccine efficacy estimates at face value due to a variety of confounding factors. Those include differing characteristics of people who get vaccinated compared with those that don’t, as well as past COVID infections providing some protection in the unvaccinated. Vaccine efficacy estimates can be influenced by the timing of people’s vaccinations, the risk factors each group may have, the waves of infection, and how waves are timed with vaccinations. Many of these factors could add up to make vaccine effectiveness appear lower than it actually is. For instance, people who were first in line to get a vaccine included those with compromised immune systems, thus increases in infection and severe disease could perhaps represent the problem of poor immune responses in those populations rather than a significant waning of protection overall.

In addition, it’s important to note that Israel defines severe disease differently than the US, counting people with high respiratory rates and blood-oxygen levels below 94 percent. In the US, studies often define severe disease as those requiring hospitalization or intensive care or those who die as a result of their infection.

Pfizer presented its own case for boosters, showing US data suggesting that protection against infection has waned but that protection against hospitalization has not. The company argued that Israel’s data foreshadows waning and suggests that boosters will prevent upticks in severe disease and death among vaccinated people.

As for safety, Pfizer and the FDA gave separate presentations that picked through Pfizer’s data on safety, which only involved 306 people between the ages of 18 and 55. The data suggests that a third dose boosted antibody levels to levels comparable if not greater than was seen following second doses. Likewise, side-effects from a third dose were similar to what was seen after a second dose, with the most common effects including pain at the injection site, fatigue, headache, chills, and muscle pain.

Overall, VRBPAC was swayed by the data from Israel suggesting that older people may soon become more vulnerable to severe disease, hospitalization, and death and that booster doses can safely increase protection. But with such little safety data on the younger groups and without a clear and growing risk of severe disease in those younger groups, the members were unconvinced that boosters should be offered to all people ages 16 and up at this time.

Final decisions

In their final deliberations, the members landed on those ages 65 and older as well as people at high risk. The cutoff and definitions are shaky. The committee did not have decisive data on what age group to draw the line at, with some committee members suggesting those above 50 or 60. In the end, the FDA reworded the final voting question, which included the cutoff of 65.

Additionally, the committee felt it was necessary to include people at high risk of severe disease from underlying conditions, given the possibility of further waning and the need to protect healthcare systems from being overwhelmed. Who might qualify under those terms is yet to be defined by an advisory committee for the Centers for Disease Control and Prevention—the Advisory Committee on Immunization Practices—which is set to meet September 22.

In a similar vein, the VRBPAC felt it was important to include those at high risk of infection due to occupational exposure, given that booster shots may reduce the risk of infection and transmission. With hospitals across the country strained and buckling under the weight of the delta coronavirus wave, the committee wanted to ensure that healthcare workers, frontline workers, and teachers could have maximum protection—again—to protect the overall healthcare systems.

Though the decision today may disappoint some hoping for a blanket green light for boosters, the committee was pleased that it followed the science and resisted any pressure from the Biden administration.

“I think this should demonstrate to the public that the members of this committee are independent of the FDA and that, in fact, we do bring our voices to the table,” Archana Chatterjee, a voting VRBPAC member and Dean of Chicago Medical School.

Moving forward, VRBPAC chair Arnold Monto noted that if the booster doses are authorized using an EUA, it will be easy to revisit data in the near future to determine if and when boosters for wider groups may be needed.

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Study: Hottest star in the Milky Way is likely remnant of ancient supernova

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Enlarge / Hubble Space Telescope mosaic image of the Crab Nebula, a six-light-year-wide expanding remnant of a star’s supernova explosion in 1054 CE

NASA/ESA/J. Hester & A. Loll (Arizona State University

In August 1181, astronomers in China and Japan witnessed a bright “guest star” in the night sky that we now know to have been a supernova—one of just a handful of recorded supernovae in our Milky Way that were visible to the naked eye. It shone brightly for a full six months before it disappeared. Astronomers haven’t been able to identify the remnant of the source for SN 1181 for centuries, and that detail is crucial to determine which class the supernova belongs to. Now, an international team of astronomers think they’ve pinpointed that source as one of the hottest stars in the galaxy within the Pa30 nebula, according to a new paper published in the Astrophysical Journal Letters.

As we’ve written previously, there are two types of known supernova, depending on the mass of the original star. An iron-core collapse supernova occurs with massive stars (greater than ten solar masses), which collapse so violently that it causes a huge, catastrophic explosion. The temperatures and pressures become so high that the carbon in the star’s core begins to fuse. This halts the core’s collapse, at least temporarily, and this process continues, over and over, with progressively heavier atomic nuclei. When the fuel finally runs out entirely, the (by then) iron core collapses into a black hole or a neutron star.

Then there is a thermonuclear supernova. Smaller stars (up to about eight solar masses) gradually cool to become dense cores of ash known as white dwarfs. If a white dwarf that has run out of nuclear fuel is part of a binary system, it can siphon off matter from its partner, adding to its mass until its core reaches high enough temperatures for carbon fusion to occur. 

There are also rarer types of supernovae. Among the earliest and most famous “guest stars” was recorded by Chinese astronomers around July 4, 1054. It was visible in broad daylight for 23 days. The remnants now form the Crab Nebula. Some have hypothesized that SN 1054 was a  so-called “electron-capture” supernova, first described some 40 years ago.

If that is indeed the case, SN 1054 has a 21st century cousin. Back in June, we reported that a team of astronomers had identified a second recent supernova—dubbed SN 2018zd—that meets all the criteria for an electron-capture supernova.  In this scenario, a star isn’t heavy enough to produce an iron core collapse supernova, and yet it’s not light enough to prevent its core from collapsing entirely. Instead, such stars stop the fusion process when their cores are composed of oxygen, neon, and magnesium. In this scenario, electrons get gobbled up by the neon and magnesium in the core, thereby causing the core to buckle under its own weight. The end result is a supernova.

According to this new analysis, SN 1181 appears to belong to another relatively rare category known as Type Iax. It’s related to the Type Ia category, in which the supernova is the result of a binary star system where one of the two stars is a white dwarf. Typically, the white dwarf siphons off hydrogen and helium from its companion star, eventually hitting a critical mass and exploding, destroying the white dwarf in the process. But there are cases, such as SN 2012Z, where the white dwarf only loses half its mass and leaves behind a zombie star as a remnant.

False-color images of Parker's star and the nebula Pa30, which scientists now believe are connected with reports of a supernova seen in 1181.
Enlarge / False-color images of Parker’s star and the nebula Pa30, which scientists now believe are connected with reports of a supernova seen in 1181.

Andreas Ritter et al., 2021

“SN 1181 was until now the only remaining historical supernova of the last millennium without a certain counterpart,” the authors wrote. For years, the most likely candidate remnant was a radio and x-ray pulsar known as 3C-58, which currently rotates about 15 times per second. That would mean the pulsar hasn’t lost much rotational energy over the last 900 years. SN 1054’s remnant, the Crab Nebula, in contrast, has lost roughly two-thirds of its rotational energy. And according to recent radio surveys of 3C-58, the pulsar is likely much older than SN 1181 and hence could not be the remnant.

Enter the disk-like nebula Pa30, first discovered by astronomers in 2013, which surrounds a rare, massive Wolf-Rayet star known as Parker’s Star. The authors determined that the dust and gas in Pa30 is expanding at more than 1100 km/sec, and the team used that velocity to derive its age: about 1000 years. This makes it an excellent candidate for the remnant of SN 1181.

“The historical reports place the guest star between two Chinese constellations, Chuanshe and Huagai. Parker’s Star fits the position well,” said co-author Albert Zijlstra of the University of Manchester. “That means both the age and location fit with the events of 1181.”

Astronomers had previously hypothesized that Pa30 and Parker’s Star resulted from the collision and ensuing merger of two white dwarf stars, producing a Type Iax supernova, and Zijllstra et al.‘s findings are in keeping with that hypothesis. “Only around 10 percent of supernovae are of this type and they are not well understood,” said Zijlstra. “The fact that SN1181 was faint but faded very slowly fits this type. It is the only such event where we can study both the remnant nebula and the merged star, and also have a description of the explosion itself. It is nice to be able to solve both a historical and an astronomical mystery.”

DOI: Astrophysical Journal Letters, 2021. 10.3847/2041-8213/ac2253  (About DOIs).

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The FAA releases initial report on Boca Chica launches, and it’s not terrible

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Enlarge / SpaceX’s Booster 4 is lifted on to its orbital launch mount in South Texas.

The Federal Aviation Administration released a draft environmental review of SpaceX’s plans for orbital launches from South Texas on Friday, kicking off a 30-day public comment period.

The long-awaited procedural step is the first of several regulatory hurdles that SpaceX must clear before obtaining final permission to launch its Super Heavy booster and Starship upper stage from a site near Boca Chica, Texas. Such a launch likely remains months away, but it now appears that the feds will ultimately greenlight South Texas for orbital launches. That seemed far from assured before today.

The document, formally called a Draft Programmatic Environmental Assessment, evaluates the potential environmental impacts of SpaceX’s Starship program, including launch and reentry. It also reviews debris recovery, the integration tower and other launch-related construction, and local road closures between Brownsville and Boca Chica beach.

For the large majority of these analyses, the FAA document finds “no significant impacts.” The impact of noise to surrounding communities, including South Padre Island located several miles away, was believed to be one of the biggest concerns. But an independent assessment found noise levels to be manageable.

One exception came under the “biological resources” category. “The FAA has determined the Proposed Action would adversely affect species listed under and critical habitat designated under the federal Endangered Species Act,” the report states. However, there may be a way to mitigate these impacts. Another potential area of concern is excessive road closures of Highway 4. This may be one reason why SpaceX is proposing an average of five Super Heavy launches a year during the operational phase of the program.

Following the release of this draft assessment, the FAA will hold virtual public hearings on Oct. 6 and 7 before the public comment period ends on Oct. 18, 2021. SpaceX founder Elon Musk asked for support on Twitter, shortly after the FAA released the draft document. “Please add your voice to the public comments,” Musk said. “Support is greatly appreciated! Humanity’s future on the moon, Mars & beyond depends upon it.”

After the public comment period closes, the FAA will finalize its environmental assessment. Following this, the FAA will issue one of three rulings: a Finding of No Significant Impact (FONSI), Mitigated FONSI, or issue a Notice of Intent to prepare an Environmental Impact Statement. A “FONSI” would allow the formal launch licensing process to proceed. If a full Environmental Impact Statement is needed, launches from South Texas would likely be delayed by months, if not years, as more paperwork is completed.

SpaceX has not revealed the full extent of its launch plans for Super Heavy and Starship, but the document suggests the company may eventually land its Super Heavy booster down range, on a platform in the Gulf of Mexico, and Starship may land in remote islands in the Pacific Ocean. SpaceX also will likely conduct launches from a platform in the Gulf of Mexico, as well as a pad at Kennedy Space Center.

The upside of Friday’s document release is that SpaceX can now move forward with some confidence that it ultimately will at least be able to conduct orbital test flights of Super Heavy and Starship from South Texas. This is critical as the site is just a couple of kilometers from the factory where the company assembles the giant rocket and spacecraft.

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