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Scientists Reveal Secrets of Desert Star Dunes

A view of the Lala Lallia star dune of the Sahara Desert, in Erg Chebbi, Morocco, as seen in an undated handout image from 2008 and obtained by Reuters on March 1, 2024. Charlie Bristow/Handout via REUTERS
A view of the Lala Lallia star dune of the Sahara Desert, in Erg Chebbi, Morocco, as seen in an undated handout image from 2008 and obtained by Reuters on March 1, 2024. Charlie Bristow/Handout via REUTERS
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Scientists Reveal Secrets of Desert Star Dunes

A view of the Lala Lallia star dune of the Sahara Desert, in Erg Chebbi, Morocco, as seen in an undated handout image from 2008 and obtained by Reuters on March 1, 2024. Charlie Bristow/Handout via REUTERS
A view of the Lala Lallia star dune of the Sahara Desert, in Erg Chebbi, Morocco, as seen in an undated handout image from 2008 and obtained by Reuters on March 1, 2024. Charlie Bristow/Handout via REUTERS

They are among the wonders of our deserts: star dunes, the vaguely pyramid-shaped sand formations up to about 1,000 feet (300 meters) tall with arms stretching out from a central peak to give them a star-like appearance when viewed from above.
Scientists on Monday unveiled the first in-depth study of a star dune, revealing the internal structure of these geological features and showing how long it took for one of them to form - more quickly than expected but still a process unfolding over many centuries.
The study focused upon a star dune in eastern Morocco called Lala Lallia, meaning "highest sacred point" in the local Berber language, situated within the Sahara Desert in a small sand sea called Erg Chebbi about 3 miles (5 km) from the town of Merzouga, close to the border with Algeria.
Lala Lallia rises about 330 feet (100 meters) above the surrounding dunes and is approximately 2,300 feet (700 meters) wide, containing about 5-1/2 million metric tons of sand.
According to Reuters, he researchers used ground-penetrating radar to peer inside the dune and employed luminescence dating to determine how long Lala Lallia has taken to form, a method based on the amount of energy trapped inside the grains of sand. The answer: about 900 years, accumulating roughly 6,400 metric tons annually as wind relentlessly blows sand through the desert.
Star dunes make up just under 10% of the dunes in Earth's deserts and are the tallest ones, surpassing other types such as crescent-shaped barchan dunes and straight and lengthy linear dunes. They also have been spotted on Mars and on Saturn's large moon Titan.
"I first encountered star dunes in Namibia 20 years ago, and was instantly amazed at the size of them. I have a vivid memory of the long climb to the top, struggling up very loose sand in the heat of the day," said geographer Geoff Duller of Aberystwyth University in Wales, co-author of the study published in the journal Scientific Reports.
"I find desert dunes very beautiful," Duller added. "The sight of the sinuous curves, and the way that the light and shadow changes with the sun mean that they always look different, whether that is in the cool of the morning, the midday sun or near sunset. The different colors of sand in different deserts are also very striking, with yellow, white, red and even black dunes in different parts of the world."
The ground-penetrating radar revealed the layers within the Lala Lallia dune, showing how it was constructed over time through accumulating sand and how parts of its internal structure resembled other types of dunes.
"Star dunes are formed in areas with complex wind regimes, which means winds blowing from different directions, and net sand accumulation, points within the desert where big piles of sand can be blown around to form giant dunes," said Birkbeck University of London sedimentologist and study co-author Charlie Bristow.
The researchers also determined that Lala Lallia is moving westerly at a speed of about 1.6 feet (0.5 meters) annually.
While many star dunes are known today, only a single ancient one has been found preserved as sandstone in the geological record, dating to about 250 million years ago, in Scotland. By revealing their internal structure, the researchers said their findings provide a guide for geologists to identify more sandstone remnants of ancient star dunes.
Earth's largest star dunes are found in the Badain Jaran desert in western China. Star dunes also are found in places including the Namib Sand Sea in Namibia, large sand seas in Algeria such as the Grand Erg Oriental and Grand Erg Occidental, and Rub' al Khali in Saudi Arabia. In North America, Great Sand Dunes National Park in Colorado contains a series of them.
"They form extraordinary and awe-inspiring landscapes," Bristow said. "From the ground they can be intimidating, mobile mountains of sand."

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Japan Wants Hardworking Citizens to Try 4-day Workweek

FILE - Commuters walk in a passageway during a rush hour at Shinagawa Station, Feb. 14, 2024, in Tokyo. (AP Photo/Eugene Hoshiko, File)
FILE - Commuters walk in a passageway during a rush hour at Shinagawa Station, Feb. 14, 2024, in Tokyo. (AP Photo/Eugene Hoshiko, File)
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Japan Wants Hardworking Citizens to Try 4-day Workweek

FILE - Commuters walk in a passageway during a rush hour at Shinagawa Station, Feb. 14, 2024, in Tokyo. (AP Photo/Eugene Hoshiko, File)
FILE - Commuters walk in a passageway during a rush hour at Shinagawa Station, Feb. 14, 2024, in Tokyo. (AP Photo/Eugene Hoshiko, File)

Japan, a nation so hardworking its language has a term for literally working oneself to death, is trying to address a worrisome labor shortage by coaxing more people and companies to adopt four-day workweeks, The Associated Press reported on Saturday.
The Japanese government first expressed support for a shorter working week in 2021, after lawmakers endorsed the idea. The concept has been slow to catch on, however; about 8% of companies in Japan allow employees to take three or more days off per week, while 7% give their workers the legally mandated one day off, according to the Ministry of Health, Labor and Welfare.
Hoping to produce more takers, especially among small and medium-sized businesses, the government launched a “work style reform” campaign that promotes shorter hours and other flexible arrangements along with overtime limits and paid annual leave. The labor ministry recently started offering free consulting, grants and a growing library of success stories as further motivation.
“By realizing a society in which workers can choose from a variety of working styles based on their circumstances, we aim to create a virtuous cycle of growth and distribution and enable each and every worker to have a better outlook for the future,” states a ministry website about the “hatarakikata kaikaku” campaign, which translates to “innovating how we work.”
The department overseeing the new support services for businesses says only three companies have come forward so far to request advice on making changes, relevant regulations and available subsidies, illustrating the challenges the initiative faces.
Perhaps more telling: of the 63,000 Panasonic Holdings Corp. employees who are eligible for four-day schedules at the electronics maker and its group companies in Japan, only 150 employees have opted to take them, according to Yohei Mori, who oversees the initiative at one Panasonic company.
The government's official backing of a better work-life balance represents a marked change in Japan, a country whose reputed culture of workaholic stoicism often got credited for the national recovery and stellar economic growth after World War II.
Conformist pressures to sacrifice for one's company are intense. Citizens typically take vacations at the same time of year as their colleagues — during the Bon holidays in the summer and around New Year’s — so co-workers can't accuse them of being neglectful or uncaring.
Long hours are the norm. Although 85% of employers report giving their workers two days off a week and there are legal restrictions on overtime hours, which are negotiated with labor unions and detailed in contracts. But some Japanese do “service overtime,” meaning it’s unreported and performed without compensation.
A recent government white paper on “karoshi,” the Japanese term that in English means "death from overwork, said Japan has at least 54 such fatalities a year, including from heart attacks.
Japan’s “serious, conscientious and hard-working” people tend to value their relationships with their colleagues and form a bond with their companies, and Japanese TV shows and manga comics often focus on the workplace, said Tim Craig, the author of a book called “Cool Japan: Case Studies from Japan’s Cultural and Creative Industries.”
“Work is a big deal here. It’s not just a way to make money, although it is that, too,” said Craig, who previously taught at Doshisha Business School and founded editing and translation firm BlueSky Academic Services.
Some officials consider changing that mindset as crucial to maintaining a viable workforce amid Japan's nosediving birth rate. At the current rate, which is partly attributed to the country's job-focused culture, the working age population is expected to decline 40% to 45 million people in 2065, from the current 74 million, according to government data.
Proponents of the three-days-off model say it encourages people raising children, those caring for older relatives, retirees living on pensions and others looking for flexibility or additional income to remain in the workforce for longer.
Akiko Yokohama, who works at Spelldata, a small Tokyo-based technology company that allows employees to work a four-day schedule, takes Wednesdays off along with Saturdays and Sundays. The extra day off allows her to get her hair done, attend other appointments or go shopping.
“It’s hard when you aren’t feeling well to keep going for five days in a row. The rest allows you to recover or go see the doctor. Emotionally, it’s less stressful,” Yokohama said.
Her husband, a real estate broker, also gets Wednesdays off but works weekends, which is common in his industry. Yokohama said that allows the couple to go on midweek family outings with their elementary-school age child.
Fast Retailing Co., the Japanese company that owns Uniqlo, Theory, J Brand and other clothing brands, pharmaceutical company Shionogi & Co., and electronics companies Ricoh Co. and Hitachi also began offering a four-day workweek in recent years.
The trend even has gained traction in the notoriously consuming finance industry. Brokerage SMBC Nikko Securities Inc. started letting workers put in four days a week in 2020. Banking giant Mizuho Financial Group offers a three-day schedule option.
Critics of the government's push say that in practice, people put on four-day schedules often end up working just as hard for less pay.
But there are signs of change.
A annual Gallup survey that measures employee engagement ranked Japan as having among the least engaged workers of all nationalities surveyed; in the most recent survey, only 6% of the Japanese respondents described themselves as engaged at work compared to the global average of 23%.
That means relatively few Japanese workers felt highly involved in their workplace and enthusiastic about their work, while most were putting in their hours without investing passion or energy.
Kanako Ogino, president of Tokyo-based NS Group, thinks offering flexible hours is a must for filling jobs in the service industry, where women comprise most of the work force. The company, which operates karaoke venues and hotels, offers 30 different scheduling patterns, including a four-day workweek, but also taking long periods off in between work.
To ensure none of the NS Group's workers feel penalized for choosing an alternative schedule, Ogino asks each of her 4,000 employees twice a year how they want to work. Asserting individual needs can be frowned upon in Japan, where you are expected to sacrifice for the common good.
“The view in Japan was: You are cool the more hours you work, putting in free overtime,” Ogino said with a laugh. “But there is no dream in such a life.”