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Scientists use tiny ‘backpacks’ on turtle hatchlings to observe their movements

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Scientists use tiny ‘backpacks’ on turtle hatchlings to observe their movements


Scientists use tiny 'backpacks' on turtle hatchlings to observe their movements
Using lightweight accelerometers has enabled the team to study turtles when visibility of them is limited. Credit: Mr. Davey Dor.

New research suggests that green turtle hatchlings ‘swim’ to the surface of the sand, rather than ‘dig,’ in the period between hatching and emergence. The findings have important implications for conserving a declining turtle population globally.

In a study published in Proceedings of the Royal Society B: Biological Sciences, scientists from UNSW’s School of Biological, Earth and Environmental Sciences used a small device, known as an accelerometer, to uncover novel findings into the behaviors of hatchlings as they emerge from their nests.

Sea turtle eggs are buried in nests 30–80cm deep. Once hatched, the newborn turtles make their way to the surface of the sand over three to seven days. But because this all happens underground, we have very little understanding of the first few days of a hatchling‘s life.

The results provided through this novel method revealed that buried hatchlings maintained a head-up orientation and unexpectedly, moved vertically through the sand by rocking forwards and backwards rather than tipping side-to-side as expected with digging.

“When I visualize a hatchling that has just come out of its egg, it is completely in the dark in its surroundings. There’s no sign to point which way is up toward the surface—yet, they will orientate themselves and move upwards regardless,” says Mr. Davey Dor, who led the study as part of his Ph.D. “Our initial findings and ‘proof’ of this new methodology opens the door for so many new questions in sea turtle ecology.”

How can you study something underground?

The image of newly hatched baby turtles moving enthusiastically across the sand and into the ocean is somewhat familiar. But what happens before then?

Once they emerge from their eggs, hatchlings move through the sand column and eventually emerge on the surface.

“It was about 64 years ago that the period of turtles hatching from their eggs and coming up to the surface was first observed,” says Mr. Dor. “And since then, people have tried different techniques to observe this phase, such as using a glass viewing pane to watch the hatchlings, or using microphones to listen to their movement.”

Each of these previous techniques has come with limitations which means it has remained difficult to study the first few days of life for turtle hatchlings.

“You just don’t think about how much work it takes for these tiny hatchlings to swim through the sand in the dark, with almost no oxygen,” says Associate Professor Lisa Schwanz. “It happens right under everyone’s feet, but we haven’t had the technology to really understand what is happening during this time.”

So Mr. Dor, A/Prof. Lisa Schwanz and Dr. David Booth, from the University of Queensland, set out to explore new ways to observe and research this obscure, little-known process.

Miniature accelerometer backpacks

Accelerometers, which measure changes in speed or direction, have previously been used to study animal movement, behaviors and physiology.

“The simple principle of the type of accelerometer we used is that it measures acceleration from three different angles,” says Mr. Dor. “So it can measure a change in velocity in a forwards and backwards motion, an up and down motion and a side to side motion.”

But until now, an accelerometer hadn’t been used in this context.

This research took place on Heron Island, a long-term monitoring nesting site for green turtles in the southern Great Barrier Reef, where nesting season typically runs from December to March.

“After locating the nests, we waited for approximately 60 days for the eggs to develop,” says Mr. Dor. “Three days before they hatched, we put a device called a hatch detector next to 10 different nests. This unique instrument measures voltage at the nest site and lets us know when the hatchlings had hatched out of their eggs.”

As soon as the team became aware that the eggs had hatched, they carefully dug down into the nest, selected the hatchling closest to the surface and attached a light-weight, miniature accelerometer onto the baby turtle, before placing it back. “We then gently layered the sand back in the way it was found,” says Mr. Dor.

It was then a waiting game to see when the hatchlings emerged. “We checked the nest site every three hours and when they did finally emerge, we retrieved the accelerometer from the hatchling carrying it.”

The accelerometer provided new data on the direction, speed and time it took for the ten hatchlings to emerge. “We analyzed the data and found that hatchlings show amazingly consistent head-up orientation—despite being in the complete dark, surrounded by sand,” says Mr. Dor.

“We found that their movement and resting periods are generally quite short, that they move as if they were swimming rather than digging, and that as they approach the surface of the sand, they restrict their movement to nighttime,” says Mr. Dor.

Conservation and nest intervention

Sea turtle populations are in decline in many parts of the world, with several species listed as endangered. The nesting phase is a major vulnerability for turtle populations and as a result, conservation management often focuses on nest intervention, including relocation, shading and watering.

Nest relocation has been used widely around the world for many years and the practice is expected to continue as the effects of climate change and rising sea levels are affecting turtle nesting. However, factors such as moisture and temperatures in the nest, which can vary when a nest is moved, can impact important performance traits of hatchlings, including their speed and movement.

“Altering nest characteristics, such as substrate moisture and depth, could have consequences for hatchlings that we currently don’t understand,” says Mr. Dor.

“This means knowledge of hatchling behavior in the sand column—and its links to offspring success—is key to future conservation practices.”

While we know that in the scramble across the sand to the water, hatchlings are at great risk from predators, “it’s also true that some hatchlings don’t even make it to that point,” says A/Prof. Schwanz. “We have so little knowledge of what makes one hatchling successfully emerge while another doesn’t, so it’s really important that we figure out what might contribute to this.”

Opening the door to further research

The latest publication confirms that using accelerometers to monitor hatchlings provides many benefits, including data of movement and behaviors, and crucially, the ability to study turtles when our visibility of them is limited.

These findings have also provided new insights and changed previous assumptions about hatchlings’ earliest days in the sand.

“There are lots of factors that we don’t really understand because we haven’t been able to observe this stage of their lives, but we hope this will change as a result of this new method, particularly in answering questions about best conservation practices,” says Mr. Dor.

The following summer, Mr. Dor returned to Heron Island to put accelerometers on multiple hatchlings in a single nest.

“So, using the next year’s data, we’ll get a sense of how coordinated the nests are, because there is a theory about whether the turtles coordinate their movements, or if they have a division of labor,” says A/Prof. Schwanz.

More information:
David Dor et al, Swimming through sand: using accelerometers to observe the cryptic, pre-emergence life-stage of sea turtle hatchlings, Proceedings of the Royal Society B: Biological Sciences (2024). DOI: 10.1098/rspb.2024.1702

Citation:
Scientists use tiny ‘backpacks’ on turtle hatchlings to observe their movements (2024, October 2)
retrieved 2 October 2024
from https://phys.org/news/2024-10-scientists-tiny-backpacks-turtle-hatchlings.html

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How do ‘double skeptics’ affect government policy on climate and vaccination?

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How do ‘double skeptics’ affect government policy on climate and vaccination?


skeptical
Credit: Pixabay/CC0 Public Domain

Governments and other policymakers around the world wrestle with how to deal with people who are skeptical of official positions and guidelines, such as climate skeptics and antivaxxers.

Earlier research has linked such skepticism to distrust of scientists among members of the public, while other studies have shown that it is difficult to erode skeptical attitudes that are psychologically motivated by factors such as bias against elite institutions or a conservative world view.

New research from the University of Cambridge, reported in the journal PLOS ONE, suggests a more tailored approach could help dispel some of this skepticism, which could have implications for the way governments deal with skepticism among their constituents.

“The research shows that there are other approaches than addressing these issues in a one-size-fits-all manner,” said study co-author Dr. Zeynep Clulow from Cambridge Judge Business School. “There are different types of skeptics, so this requires different strategies aimed at dispelling skepticism.”

“These findings can help policymakers develop more targeted strategies and focus more attention on groups that are persuadable, rather than being resigned to considering every skeptic to be some consistent conspiracist on every issue,” said co-author Professor David Reiner, also from Cambridge Judge Business School.

The research analyzed the drivers of skepticism toward climate change and COVID-19 vaccination, based on a survey taken in early 2021 by polling firm Ipsos Mori, when most countries had been through the first wave of the pandemic and begun rolling out vaccination programs. Nationally-representative samples of 2,000 people were polled in each of eight countries: Australia, Brazil, China, India, Japan, South Africa, the UK and the US.

The study found that while the vast majority of people support COVID-19 vaccinations and recognize the threats posed by climate change, there were small groups who are skeptical of either climate change or COVID-19 vaccination, and an even smaller group who were skeptical of both.

For this smaller group of “double skeptics,” their attitudes were motivated by an underlying skeptical mindset, which was distrustful of institutions in general, including scientists and mainstream media.

Single-issue skeptics, in contrast, were primarily distrustful of scientists. The research found that people who completely distrust scientists were approximately four times more likely to be antivaxxers and five times more likely to be climate skeptics than double skeptics.

According to the researchers, this distinction suggests that efforts to overcome isolated predictors of skepticism—such as building trust in scientists, economic support and information campaigns—are more likely to boost support for policies designed to create societal responses to global challenges.

The same is not true for double skeptics: such strategies are likely to be ineffective or even counter-productive for people whose skepticism is associated with a more generalized skeptical worldview.

Double skeptics tend to possess many of the typical skeptic characteristics, such as high distrust in social institutions and right-wing political orientation, which are collectively suggestive of an underlying skeptic mindset rather than a specific distrust of scientists.

Reasons why distrust in scientists might drive skepticism on climate change and COVID-19 vaccination include the complex nature of both issues that make it difficult for non-scientists to fully understand, and the financial and behavioral costs related to mitigation of these issues.

The surveys asked respondents to rate their trust in university scientists as part of a broader question that also probed trust in institutions and actors ranging from corporations to environmental NGOs to television news. They were also asked to rate trust in certain specific sources, including oil and gas companies, Greenpeace, Greta Thunberg, and social media.

While many respondents showed some degree of skepticism (35% did not consider climate change a major threat to their country, and 17% were unlikely to take a COVID-19 vaccine if offered one), only a very small minority (1.4%) chose the most skeptical response towards both issues.

Even in the United States, only 4% of respondents were skeptical towards both issues and that group was less than 2% of the sample in the other seven countries. Similarly, less than 5% of respondents in six countries completely dismissed the threat of climate change (Australia at 9% and the US at 14% were higher).

The research also found that skepticism is inversely related with education, science knowledge, and perceived responsibility for combating climate change. Skepticism was higher among men, people who distrust television, and those with right-wing political views.

The researchers also found that people who prioritized the economy over the mitigation of climate change or COVID-19, or both, were significantly more likely to distrust scientists.

The researchers note two important limitations of their study sample: respondents in emerging economies were recruited from urban centers, so the views of rural citizens may not be accurately reflected; and Chinese respondents were not asked about their political views.

The other caveat is that the survey was taken when almost no one had received the COVID-19 vaccine and when many countries were still under some form of lockdown.

“While acknowledging that this was a particularly unusual time, we expect the finding that double skeptics comprise a small fraction of total pool of skeptics to be robust and we would expect to see this finding extended to other topics,” said Clulow.

“Painting all skeptics as irredeemable conspiracists is both counterproductive and incorrect,” said Reiner.

“Most climate skeptics are not very concerned about taking a vaccine and vice versa. Most skeptics are single-issue skeptics and will need to be engaged on the specifics of the issue, which will, no doubt, be challenging, but they do not exhibit the more fundamental, all-encompassing skepticism we find among double-skeptics that extends to all societal institutions and media outlets.”

More information:
How to distinguish climate sceptics, antivaxxers, and persistent sceptics: Evidence from a multi-country survey of public attitudes, PLoS ONE (2024). www.jbs.cam.ac.uk/wp-content/u … 3/12/eprg-wp2205.pdf

Citation:
How do ‘double skeptics’ affect government policy on climate and vaccination? (2024, October 2)
retrieved 2 October 2024
from https://phys.org/news/2024-10-skeptics-affect-policy-climate-vaccination.html

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part may be reproduced without the written permission. The content is provided for information purposes only.





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Study traces wild cat eye color diversity to ancient ancestor

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Study traces wild cat eye color diversity to ancient ancestor


Blue, green, gold: Why eyes of wild cats vary in color
Credit: iScience (2024). DOI: 10.1016/j.isci.2024.110903

Fans of Clementine, the cat who recently captivated TikTok with her rare eye color, should take note. The piercing golden gaze of cheetahs, the striking blue stare of snow leopards, and the luminous green glare of leopards are all traits that can be traced to one ancestor, an ocelot-like feline progenitor that roamed Earth more than 30 million years ago.

In a new study published in iScience, Harvard researchers say this ancestral population likely featured felines with both brown and gray eyes, the latter paving the way for the rapid and wide diversification of iris color seen in cat species today.

“When I started this study I asked, ‘What do we know about eye color?’ And the truth is, very little, as there are basically almost no phylogenetic evolutionary studies on eye color,” said lead author Julius Tabin, a Griffin Graduate School of Arts and Sciences student in the Department of Organismic and Evolutionary Biology.

Most studies focus on the distribution of eye colors in a species, or on the genes involved in making eye color in humans and domesticated animals. Studies on eye color in animal populations are rare due to the challenges of preservation and lack of diversity—most animals have brown eyes.

While eye color in humans is likely a result of sexual selection, and in domesticated animals a result of artificial selection, Tabin wondered what spurred the wide diversity in wild Felidae. Without fossil preservation to rely on, Tabin took a novel approach by analyzing digital images from sources such as iNaturalist to identify and categorize the varied eye colors in 52 felid taxa.

Tabin and co-author Katherine Chiasson, a Ph.D. candidate at Johns Hopkins University, created an algorithm to map iris colors onto a phylogenetic tree of Felidae.

“We found a lot of variability of color between species,” said Tabin, “but shockingly, we also found a lot of intraspecific variability. Most species have a singular eye color with no variation. So, it’s really surprising that once you get into the cats—lions, tigers, panthers, etc.— we see all these different eye colors. There are actually very few Felidae species that have only a singular eye color in their population.”

Equipped with the colors mapped onto the phylogenetic tree, the researchers set out to reconstruct the ancestral state. They found that early, pre-felid lineages (the ancestor of felids and their closest relatives, the linsangs) had brown eyes only. However, after the linsang species branched off, gray-eyed felines appeared alongside brown-eyed ones.

“It’s likely this happened due to a genetic mutation that drastically decreased the pigment in the eye,” Tabin said. Melanin can be either eumelanin, which is brown, or pheomelanin, which is yellow.

To go from a brown eye to a gray eye would require a decrease of eumelanin. That decrease would lead to an eye that is not fully brown and not fully gray, but a brownish gray color, which is what the researchers found.

Those gray-eyed felines opened the door to a burst of greens, yellows, and blues, providing an anchor between brown eyes and the new colors.

“Blue eyes require carefully balanced low levels of pigment and are likely recessive in felids. A wild population would probably not be able to maintain blue eyes in a population with only one blue-eyed individual among a sea of brown eyes.

“It’s probable that you would need something lighter than brown, but not as light as blue, to be the mediator. And that’s what you see: In every single cat species with blue eyes, they also have gray eyes,” said Tabin.

Tabin and Chiasson also observed that brown eyes and yellow eyes rarely coexist in a species. They said they were surprised to find a positive correlation between yellow eyes and round pupils, and a negative correlation between brown eyes and round pupils.

The researchers found no significant correlations for activity mode, zoogeographical region, habitat, and uniformity of eye color, which leaves the adaptive benefit of having varied eye colors an open question to pursue.

The researchers not only reconstructed the general eye color types present at each evolutionary node, but they were also able to predict the exact color of each ancestor’s eye.

“Being able to reconstruct color quantitatively is one of the paper’s greatest strengths, because it means we are the first animals to see the color of these eyes since these felids were alive millions of years ago,” Tabin said.

For Chiasson the study was special in part because all the resources they used are freely available online. “The fact that rigorous studies like ours can be done by anyone with an internet connection and some curiosity is indicative of a field-wide revolution that is increasing the accessibility of science around the world.”

The study opens an opportunity for more investigation of the evolutionary importance of gray eyes, as well as eye-color evolution in natural populations, Tabin said. “I’m still riding high on the excitement of knowing that the felid ancestor had both brown and gray eyes, because that’s something I didn’t go in expecting or even thinking about.”

More information:
Julius A. Tabin et al, Evolutionary insights into Felidae iris color through ancestral state reconstruction, iScience (2024). DOI: 10.1016/j.isci.2024.110903

Provided by
Harvard University


This story is published courtesy of the Harvard Gazette, Harvard University’s official newspaper. For additional university news, visit Harvard.edu.

Citation:
Study traces wild cat eye color diversity to ancient ancestor (2024, October 2)
retrieved 2 October 2024
from https://phys.org/news/2024-10-wild-cat-eye-diversity-ancient.html

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Scientists unlock secret of ‘Girl With Pearl Earring’

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Scientists unlock secret of ‘Girl With Pearl Earring’


Girl With The Pearl Earring
Credit: Pixabay/CC0 Public Domain

Johannes Vermeer’s “Girl With The Pearl Earring” is one of the world’s most popular paintings—and now scientists believe they know why, by measuring how the brain reacts when the work is viewed.

The Mauritshuis museum in The Hague, which houses the 17th century masterpiece, commissioned neuroscientists to measure brain output when viewing the portrait and other well-known works.

They discovered that the viewer is held captive by a special neurological phenomenon they called “Sustained Attentional Loop”, which they believe is unique to the “Girl With The Pearl Earring”.

The viewer’s eye is automatically drawn first to the girl’s own eye, then down to her mouth, then across to the pearl, then back to the eye—and so it continues.

This makes you look at the painting longer than others, explained Martin de Munnik, from research company Neurensics that carried out the study.

“You have to pay attention whether you want to or not. You have to love her whether you want to or not,” he said.

By measuring brainwaves, the scientists also discovered the precuneus, the part of the brain governing consciousness and personal identity, was the most stimulated.

“It was predictable that the Girl was special. But the ‘why’ was also a surprise to us,” said De Munnik.

He said it was the first known study to use EEG and MRI brain scanning machines to measure the neurological response to artwork.

“The longer you look at somebody, the more beautiful or more attractive somebody becomes,” he noted, which also explains the popularity of the Dutch master’s subject.

“Why are you familiar with this painting and not with the other paintings? Because of this special thing she has.”

‘The brain doesn’t lie’

The scientists also compared the neurological response when looking at the genuine painting in the museum versus being confronted with a reproduction.

They found the emotional reaction experienced by the viewer was ten times stronger for an original than a poster.

To carry out the tests, scientists attached an eye tracker and cap to track brainwaves on 10 subjects that were shown the real paintings but also reproductions.

It shows the importance of seeing original art, said Mauritshuis Director Martine Gosselink.

“It’s so important to engage with art, whether it’s photography, or dance, or old masters from the 17th century,” the director, 55, told AFP in an interview.

“It is important, and it really helps to develop your brain… The brain doesn’t lie,” she added.

Vermeer often drew the focus onto one spot in his works, with the surrounding details more blurred, she explained.

However, the “Girl With The Pearl Earring” has three such focal points—the eye, mouth, and pearl—and Gosselink said this set the work apart from other Vermeer paintings.

“Here we see somebody really looking at you, whereas all other paintings by Vermeer, you see someone writing or doing some needlework, or a person busy doing something,” she said.

“But that’s the big difference with this girl. She’s watching you.”

De Munnik, 65, said it would be interesting to carry out similar studies on other famous paintings, such as Da Vinci’s Mona Lisa for example.

Mauritshaus director Gosselink alluded to a friendly rivalry between the two great works.

“People sometimes call (The Girl With The Pearl Earring) the Mona Lisa of the North, but I think times are changing, so maybe the Mona Lisa is the Girl of the South,” she joked.

© 2024 AFP

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Scientists unlock secret of ‘Girl With Pearl Earring’ (2024, October 2)
retrieved 2 October 2024
from https://phys.org/news/2024-10-scientists-secret-girl-pearl-earring.html

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Study highlights managers’ role in telework success

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Study highlights managers’ role in telework success


telework
Credit: Pixabay/CC0 Public Domain

Amazon has announced that it will end remote work for its office staff starting in January 2025. A decision that seems to go against the current, as the increasing pace of digitalization since the recent pandemic has marked a turning point for teleworking. Prior to the 2020 health crisis, this form of working was practically unimaginable for many companies but, since then, its presence has continued to grow in importance.

According to the Adecco Employment Opportunities and Satisfaction Monitor, produced by The Adecco Group Institute, telework in Spain increased by 19% in 2023, with more than 3 million people working remotely. This is more than double the number of employees doing so in 2019, i.e., before the COVID health crisis.

Working remotely is a concept that, no matter how much it grew with the pandemic and stabilized at a higher level afterwards, has not always generated a consensus. Sometimes companies have resisted implementing teleworking, which involves a number of challenges, such as the types of jobs for which it should be used, the use of technological resources, and communication between the different members of teams.

One hurdle is the management teams, whose job it is to establish whether teleworking is a good fit with the company’s operations; this strategic decision depends largely on them. A study by the Universitat Oberta de Catalunya (UOC) surveyed 186 people (most over the age of 45 and almost 45% of them women) from different European countries to establish the determining factors for managers in the implementation of teleworking in their companies.

The research, published in the journal Human Resources Management and Services, found that managers’ opinions of teleworking can make all the difference in its implementation in organizations. The study was carried out by Josep Lladós, Prof. Antoni Meseguer, Eva Rimbau and Mar Sabadell, members of teaching and research staff at the UOC’s Faculty of Economics and Business and of the Digital Business Research Group (DigiBiz). It indicates not only the key skills managers need in order to create a suitable context for teleworking, but also the aspects to be borne in mind to drive change.

The most important aspects for convincing managers

This research arose from the hypothesis that managers are the key to establishing and promoting teleworking in organizations. More specifically, it is essential that their perceptions of teleworking are positive and that they believe they have the necessary skills to lead teleworking teams.

According to the study, for managers, an inclination to adopt teleworking stems mainly from the perception that it will be useful for the organization and, at the same time, easy to implement. The first factor that affects their perception of the usefulness of teleworking is the impact they expect it to have on work performance.

“Managers can gauge the improvement in work performance with indicators such as the number of tasks carried out, the meeting of targets, the quality of the work delivered, absenteeism, etc. Although it’s difficult to objectively measure the impact of teleworking on efficiency and productivity, managers’ positive perception around how it affects their tasks impacts their perception of its usefulness,” said Eva Rimbau.

The skills needed to successfully lead remote work

As the study indicates, the implementation of teleworking in companies depends not only on managers’ views of their workers and the implications of usefulness or work performance, but also on their perception of themselves—that is, their own ability to take this type of work on board—and their relationship with employees.

“It’s essential that managers trust workers and manage their teams on the basis of outcomes or goals, not attendance or the number of hours worked,” explained Rimbau. The result is a “virtuous circle”: greater trust, greater potential for achieving positive outcomes and, in the case of workers, proactively taking on more duties to meet workloads.

The lack of face-to-face contact and coordination-related difficulties are some of the challenges faced by managers when implementing teleworking. This is why, as the research shows, managers’ confidence in their abilities to manage and supervise a group remotely is extremely important.

In addition, as Rimbau pointed out, to achieve this self-perception “managers must develop skills to build, motivate, recognize and hold teams accountable in a teleworking environment, using digital tools to communicate and interact effectively. They must avoid professional isolation, foster collaboration and trust, and adapt leadership and supervision to the digital context.” Workers need not just “bosses,” but leaders capable of fostering teamwork in any type of work situation.

The need for an appropriate context

Managers’ predisposition to implement teleworking is also affected by the surrounding influences, “such as pressure from peers and superiors and compatibility with the organizational culture,” Rimbau acknowledged. If a company’s senior management, or larger benchmark corporations in the industry, support teleworking, people in management roles will be more predisposed to adopt it.

Another key factor in adopting teleworking is the ability of managers to lead change, but, as the researcher pointed out, “the more digital and knowledge-based a company’s activities are, the easier it will be to adopt teleworking broadly and successfully.”

Technological barriers can have an impact on implementation, so it is essential that both workers and company possess the appropriate resources and that they digitize their processes and ways of working.

More information:
Josep Lladós-Masllorens et al, Telework and new work practices: The role of managers, Human Resources Management and Services (2024). DOI: 10.18282/hrms.v6i2.3454

Citation:
Study highlights managers’ role in telework success (2024, October 2)
retrieved 2 October 2024
from https://phys.org/news/2024-10-highlights-role-telework-success.html

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