Category: Science

People who don’t habitually turn off their automatic sprinklers are wasting water, say researchers.

In Florida, with a population of 22 million, a figure projected to hit 27.8 million by 2050, residents need to conserve the precious resource.

Preserving water boils down to good habits. It can be as simple as whether you intend to save water or not, say researchers, who would like to change the behavior of those who leave their sprinklers on when it’s raining.

“A lot of people do not think about how rain plays into the total amount of water a yard receives,” says Laura Warner, an associate professor of agricultural education and communication at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS).

“So, if someone wants to apply a half-inch of water to their lawn, they may set their irrigation system to do so regularly, and then if it rains, that is just ‘extra.’ It would be advantageous to shift people’s mindsets, so they consider rain first and irrigation supplemental.”

Warner and John Diaz, associate professor of agricultural education and communication, are coauthors of a new study that examines whether homeowners intend to turn off their irrigation when it rains—the so-called “intenders.”

The researchers conducted an online survey of 331 Florida residents who identified themselves as users of automated sprinkler systems.

They wanted to know whether homeowners intended to turn off their water, based on recent or current rain.

To find their answer, researchers asked questions such as, “How likely are you to use local weather data to turn off your irrigation when recent rainfall is adequate for your yard in the next month?” Respondents could select from “very unlikely” to “very likely” for all three questions.

Researchers labeled respondents with the highest score as “intenders.” In other words, the person plans to turn off the irrigation system when it’s raining. They also intend to turn off their water if it’s rained a lot recently and see no reason to water their lawn.

Warner and Diaz want to change the habits of “non-intenders.”

“Rather than just providing information on how to conserve water or why—which is not terribly effective—we want to connect with people and have them connect with water resources on a deeper psychological level,” Warner says. In other words, homeowners must feel a sense of obligation to conserve water.

To move toward wiser lawn-irrigation habits, UF/IFAS Extension agents, governments, homeowners’ associations, and neighbors can nudge residents to stop or reduce irrigating when it’s raining. One way to do that is by pointing out that other homeowners are turning off their sprinklers, Warner says.

Sometimes, reminders such as signs at the entrance to a subdivision help. They tell residents how much rain fell the week before and ask residents if they need to irrigate, she says.

“Considering irrigation water is potable—meaning it is the same limited source of drinking water we share—the stakes are pretty significant,” she says. “Not to mention the incredible quantity of water that can be saved and the related monetary savings on utility bills.”

The study appears in Urban Water Journal.

Source: University of Florida

Researchers have discovered for the first time how deadly hard-to-treat breast cancers persist after chemotherapy.

The findings reveal why patients with these cancers don’t respond well to immunotherapies designed to clear out remaining tumor cells by revving up the immune system.

Thanks to advances in cancer therapies, most forms of breast cancer are highly treatable, especially when caught early.

But the last frontier cases—those that can’t be treated with hormone or targeted therapies and don’t respond to chemotherapy—remain the deadliest and hardest to treat.

The process of surviving chemotherapy triggers a program of immune checkpoints that shield breast cancer cells from different lines of attack by the immune system. It creates a “whack-a-mole” problem for immunotherapy drugs called checkpoint inhibitors that may kill tumor cells expressing one checkpoint but not others that have multiple checkpoints, according to a new study published in the journal Nature Cancer.

“Breast cancers don’t respond well to immune checkpoint inhibitors, but it has never really been understood why,” says corresponding author James Jackson, associate professor of biochemistry and molecular biology at Tulane University School of Medicine.

“We found that they avoid immune clearance by expressing a complex, redundant program of checkpoint genes and immune modulatory genes. The tumor completely changes after chemotherapy treatment into this thing that is essentially built to block the immune system.”

Researchers studied the process in mouse and human breast tumors and identified 16 immune checkpoint genes that encode proteins designed to inactivate cancer-killing T-cells.

“We’re among the first to actually study the tumor that survives post-chemotherapy, which is called the residual disease, to see what kind of immunotherapy targets are expressed,” says first author Ashkan Shahbandi, an MD/PhD student in Jackson’s lab.

The tumors that respond the worst to chemotherapy enter a state of dormancy—called cellular senescence—instead of dying after treatment. Researchers found two major populations of senescent tumor cells, each expressing different immune checkpoints activated by specific signaling pathways. They showed the expression of immune evasion programs in tumor cells required both chemotherapy to induce a senescent state and signals from non-tumor cells.

They tested a combination of drugs aimed at these different immune checkpoints. While response could be improved, these strategies failed to fully eradicate the majority of tumors.

“Our findings reveal the challenge of eliminating residual disease populated by senescent cells that activate complex immune inhibitory programs,” Jackson says.

“Breast cancer patients will need rational, personalized strategies that target the specific checkpoints induced by the chemotherapy treatment.”

Source: Tulane University

WASHINGTON — As Satellogic prepares to launch its latest imaging satellites, the company has slashed revenue projections, resulting in layoffs and delays in construction of a new factory.

Four NewSat satellites, built by Satellogic, are among the 114 payloads to be launched on SpaceX’s Transporter-6 dedicated smallsat rideshare mission. That mission is scheduled to launch Jan. 3 at 9:56 a.m. Eastern on a Falcon 9 from Cape Canaveral Space Force Station in Florida. Satellogic signed a contract with SpaceX in May 2022 to launch 68 satellites on an unspecified number of launches.

The four satellites will join 26 currently in operation by Satellogic that provide high-resolution imagery. The company, in a business update Dec. 15, said it expected to launch 18 to 21 satellites in 2023, giving it enough satellites to map the Earth every two weeks.

That business update, which included the company’s financial results from the first half of 2022, showed revenue lagging earlier projections. The company recorded $2.4 million in revenue in the first half of the year, primarily from two unnamed customers, according to filings with the Securities and Exchange Commission.

Satellogic said in its business update it was projecting revenues of $6-8 million for all of 2022, and an adjusted earnings before interest, taxes, depreciation and amortization (EBITDA) loss of $55-60 million. By contrast, in an analyst day presentation in November 2021, part of going public through a SPAC merger, Satellogic projected revenue of $47 million for 2022 and an adjusted EBITDA loss of $2 million.

Emiliano Kargieman, chief executive of Satellogic, acknowledged he was “disappointed” with the revenue from the first half of the year, but remained optimistic about the company’s long-term trajectory, citing an increase in demand for its imagery seen in the second half of the year. “Our bookings and current pipeline support continued strong growth into 2023,” he said in a Dec. 15 earnings call.

The company, which in November 2021 projected revenues of $132 million in 2023, growing to $787 million in 2025, now projects $30-50 million in revenues in 2023, increasing to $140-200 million in 2025. Satellogic projects an adjusted EDBITA loss of $20-35 million in 2023, reaching breakeven in 2024 and growing to positive $35-90 million in 2025.

Kargieman said the company now has a better idea of the sales cycle for its imagery and other products. “After another year of talking to customers, we’re extremely confident in the numbers that we’re guiding for next year,” he said.

The diminished revenues have forced the company to cut costs. That included laying off 18% of its workforce in the third quarter, reducing its staff to about 380 people. Rick Dunn, Satellogic’s chief financial officer, said the number of employees would remain “more or less flat” in 2023.

The company has also scaled back the growth of its constellation. In that November 2021 presentation, Satellogic projected having 111 satellites in orbit in 2023. The company will instead end 2023 with no more than 47 satellites, although Kargieman said in the call that some of the 10 satellites it launched in October 2020 could be retired by the end of 2023 as they reach the end of their three-year design life.

With those reduced projections, Satellogic has delayed completion of a new high-throughput satellite manufacturing facility it planned to open in 2022 in the Netherlands. That factory, which Satellogic said in late 2021 would be fully operational by the start of 2023, was designed to produce 25 satellites a quarter.

Kargieman said the company’s existing factory in Uruguay can produce 24 satellites a year, sufficient for its near-term needs. “Going forward, we can continue to grow that capacity,” he said, increasing it potentially by a factor of two or three. The Dutch factory will go into service when the company is ready to scale up the constellation to the 300 satellites needed for daily remapping of the Earth. “The exact timing is yet to be defined.”

Satellogic is now offering to sell satellites, rather than just imagery, to customers. Dunn projected that at least 25% of the company’s revenues in 2023 would come from this new “space systems” business line, although weighted towards the second half of the year.

The rest of the company’s revenues will continue to come from imagery sales as well as its “constellation as a service” or dedicated satellite constellation business line, where governments and other organizations pay to gain priority access to Satellogic’s constellation over a designated area. One example Kargieman cited was an agreement with the government of Albania announced in September to provide imagery over its territory. The three-year deal is worth $6 million and includes naming two NewSat satellites launching on Transporter-6 Albania-1 and -2.

Satellogic announced Dec. 13 a letter of intent with the Mexican space agency AEM for a similar constellation-as-a-service agreement, but the company did not disclose when the contract would be finalized or its anticipated value. However, the Indian space agency ISRO announced Dec. 30 that it met with AEM officials, who asked ISRO for assistance in building and launching a remote sensing satellite.

Satellogic, which raised $168 million when its SPAC merger closed in January 2022, projected having $78-82 million of cash on hand at the end of 2022. That is enough, Kargieman said, to get the company to breakeven in 2024. “We don’t require additional financing,” he said. “We’re really in control of how much we spend and how much we invest into our future business, so we don’t expect to be raising additional financing.”

WASHINGTON — A cubesat launched on Artemis 1 missed its original chance to go into orbit around the moon but could still carry out its primary mission if engineers fix its thrusters in the coming weeks.

The NASA-funded LunaH-Map spacecraft, a six-unit cubesat, was one of 10 cubesat secondary payloads flown on the Artemis 1 mission on the inaugural launch of the Space Launch System Nov. 16. Those payloads were deployed from the SLS upper stage several hours after liftoff.

In the months leading up to the liftoff there were concerns that the batteries on LunaH-Map might have drained during its long wait for launch. The cubesat could not be charged after it was secured on the rocket in the fall of 2021.

However, the batteries were in good condition when the spacecraft transmitted its first telemetry shortly after deployment. “Our batteries were at 70% state of charge,” said Craig Hardgrove, principal investigator for LunaH-Map at Arizona State University, during a presentation about the mission at the Fall Meeting of the American Geophysical Union Dec. 15. “That was in line with our very optimistic predictions.”

While the spacecraft had sufficient power, it ran into problems with its propulsion system. “We had a very brief window to fire our propulsion system and hit a lunar gravity assist to get back to the moon,” he said. However, the thrusters failed to operate as expected to enable that maneuver to go into lunar orbit.

LunaH-Map is equipped with a BIT-3 ion thruster from Busek that uses solid iodine fuel. Hardgrove said Doppler ranging data suggests that a valve is partially stuck, allowing some iodine through but not enough to generate the required thrust.

Spacecraft engineers are trying to correct the problem with heaters in the propulsion system to free up the valve. “The sticking is something that we knew about,” he said, suggesting it came from the long wait for the launch.

If the problem can be fixed by mid-January, he said the spacecraft could take an alternative trajectory to the moon, arriving in January 2024. After that, there are options for sending LunaH-Map to rendezvous with or fly by a near Earth asteroid.

Other spacecraft systems are working well, he said. The spacecraft’s primary instrument, a neutron spectrometer designed to look for water ice deposits at the lunar south pole, collected data as it flew by the moon five days after launch. “It shows that this instrument is capable of performing the science investigation that we had planned to do,” Hardgrove said.

LunaH-Map is not the only cubesat launched on Artemis 1 that suffered technical problems. A Japanese cubesat called OMOTENASHI that was designed to perform a “semi-hard” landing on the moon failed to generate enough power from its solar arrays to communicate with Earth and was declared a loss.

Controllers have struggled to contact the CubeSat to Study Solar Particles (CuSP), which also appeared to encounter a battery problem, and Near Earth Asteroid Scout, a cubesat with a solar sail to fly by an asteroid. Lockheed Martin’s LunIR cubesat encountered an “unexpected issue with our radio signal,” the company said Dec. 8, but still considered the mission a useful technology demonstration.

Hardgrove, in his conference talk, remained optimistic about LunaH-Map. “We’re not dead. We’re doing great,” he said. “I think we’re hopefully going to ignite our propulsion system soon.”