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After injury, one species of comb jelly can fuse to become one

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After injury, one species of comb jelly can fuse to become one


After injury, one species of comb jelly can fuse to become one
Credit: Mariana Rodriguez-Santiago

Researchers reporting in the journal Current Biology on October 7 have made the surprising discovery that one species of comb jelly (Mnemiopsis leidyi) can fuse, such that two individuals readily turn into one following an injury. Afterwards, they rapidly synchronize their muscle contractions and merge digestive tracts to share food.

“Our findings suggest that ctenophores may lack a system for allorecognition, which is the ability to distinguish between self and others,” says Kei Jokura of the University of Exeter, UK, and National Institutes of Natural Sciences in Okazaki, Japan. “Additionally, the data imply that two separate individuals can rapidly merge their nervous systems and share action potentials.”

Jokura and colleagues made the observation after keeping a population of the comb jellies in a seawater tank in the lab. They noticed an unusually large individual that seemed to have two backends and two sensory structures known as apical organs instead of one. They wondered if this unusual individual arose from the fusion of two injured jellies.

To find out, they removed partial lobes from other individuals and placed them close together in pairs. It turned out that, nine out of 10 times, it worked. The injured individuals became one, surviving for at least three weeks.

Further study showed that after a single night, the two original individuals seamlessly became one with no apparent separation between them. When the researchers poked at one lobe, the whole fused body reacted with a prominent startle response, suggesting that their nervous systems were also fully fused.






Synchronization of muscle contraction. Credit: Mariana Rodriguez-Santiago

“We were astonished to observe that mechanical stimulation applied to one side of the fused ctenophore resulted in a synchronized muscle contraction on the other side,” Jokura said.

More detailed observations showed that the fused comb jellies had spontaneous movements for the first hour. After that, the timing of contractions on each lobe started to synch up more. After just two hours, 95% of the fused animal’s muscle contractions were completely synchronous, they report.

They also looked closely at the digestive tract to find that it also had fused. When one of the mouths ingested fluorescently labeled brine shrimp, the food particles worked their way through the fused canal. Eventually, the comb jelly expelled waste products from both anuses, although not at the same time.

The researchers say it remains unclear how the fusion of two individuals into one functions as a survival strategy. They suggest that future studies will help to fill the gaps in understanding, with potential implications for regenerative research.

“The allorecognition mechanisms are related to the immune system, and the fusion of nervous systems is closely linked to research on regeneration,” Jokura says. “Unraveling the molecular mechanisms underlying this fusion could advance these crucial research areas.”

More information:
Rapid Physiological Integration of Fused Ctenophores, Current Biology (2024). DOI: 10.1016/j.cub.2024.07.084. www.cell.com/current-biology/f … 0960-9822(24)01023-6

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After injury, one species of comb jelly can fuse to become one (2024, October 7)
retrieved 7 October 2024
from https://phys.org/news/2024-10-injury-species-jelly-fuse.html

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Study finds donations more effective than discounts for delayed delivery

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Study finds donations more effective than discounts for delayed delivery


shopping delivery
Credit: Pixabay/CC0 Public Domain

A new study finds consumers are more willing to accept slower delivery from retailers when ordering products online if the retailers agree to donate to a charitable cause. The finding suggests a path forward for companies that hope to ease stresses associated with providing the fastest possible delivery times. The paper, “Not-So-Speedy Delivery: Should Retailers Use Discounts or Donations to Incentivize Consumers to Choose Delayed Delivery?,” is published in the Journal of Retailing.

“Retailers feel pressure to provide quick delivery to consumers, but the logistics of delivering purchases quickly can be costly and complicated—and may be subject to disruptions outside of the retailer’s control,” says Stefanie Robinson, co-author of the study.

“To convince consumers to opt for slower delivery options, some retailers have adopted programs that offer consumers financial incentives. For example, you may get $1 off if you choose the three-day delivery option instead of the overnight delivery option.”

“We wanted to know if a better incentive exists for getting consumers to opt for slower deliveries,” says Robinson, who is an associate professor of marketing in North Carolina State University’s Poole College of Management. “Specifically, our focus was on comparing a discount incentive to something new—a donation incentive which involves the retailer making a $1 donation to a charity.”

To learn which incentives consumers found most appealing, the researchers conducted a series of six studies that cumulatively involved more than 2,000 study participants. The key finding was that consumers were more likely to opt for the slow delivery option if the company made a donation to a charity rather than a financial reward that benefited the consumer, such as a discount on their purchase. This was true across demographic groups, regardless of gender, income level and so on.

“Our findings suggest that consumers view donations to be more of a fair trade-off for delayed delivery than other financial incentives,” Robinson says.

The researchers found that two other factors can also come into play.

“First, we found that people’s willingness to accept the discount option—rather than the donation incentive—went up considerably if the retailer also explained why they wanted consumers to select a delayed delivery,” Robinson says. “For example, if a retailer said the delayed delivery option reduced the environmental effects, people were just as willing to accept the delay with the discount incentive as they were to accept the delay with the donation incentive.”

Second, the donation incentive did not improve people’s willingness to accept a delayed delivery if the items being delivered were utilitarian.

“For example, if someone needed batteries, the donation incentive did not outperform the discount incentive,” Robinson says. “In other words, if it’s something people actually need, it doesn’t matter which incentive the retailer offers.

“We think these findings offer practical, real-world guidance for retailers,” says Robinson. “There are times when retailers can’t offer speedy delivery, and this paper shows that offering a donation incentive can motivate consumers to opt for slower delivery options.”

The corresponding author of the study is Katie Kelting, an associate professor of marketing at Saint Louis University. The paper was co-authored by Stacy Wood, the Langdon Distinguished University Professor of Marketing in NC State’s Poole College of Management.

More information:
Katie Kelting et al, Not-so-speedy delivery: Should retailers use discounts or donations to incentivize consumers to choose delayed delivery?, Journal of Retailing (2024). DOI: 10.1016/j.jretai.2024.09.002

Citation:
Study finds donations more effective than discounts for delayed delivery (2024, October 7)
retrieved 7 October 2024
from https://phys.org/news/2024-10-donations-effective-discounts-delayed-delivery.html

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Scientists develop machine learning tool to accurately identify Arabic dialects in 22 Arabic-speaking countries

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Scientists develop machine learning tool to accurately identify Arabic dialects in 22 Arabic-speaking countries


Scientists develop machine learning tool to accurately identify Arabic dialects  in 22 Arabic-speaking countries
The project has the potential to enhance communication and accessibility for millions of Arabic speakers worldwide. Credit: Dr. Hala Georges, College of Fine Arts and Design, University of Sharjah.

Scientists from the University of Sharjah believe they have created an artificial intelligence system that can automatically identify which Arabic dialect someone is speaking. The work is published in IEEE Xplore.

They say their system unravels the rich and complex tapestry of Arabic dialects which hitherto conventional speech systems fall short of accurately interpreting and identifying.

“Arabic is a rich language with many regional dialects, and each one has its own unique vocabulary, expressions, and pronunciation. This diversity makes it challenging for technology to accurately understand and differentiate between them,” said Ashraf Elnagar, Professor of Computer Science and Intelligence Systems.

“To address this, we developed a system that can automatically identify which Arabic dialect someone is speaking.”

The official language in 22 countries spanning the Middle East, North Africa and the Arabian Peninsula, Arabic is one of the most spoken languages globally with more than 370 million people having it as their mother tongue. It is also one of the world’s most immersed languages in culture and those having it as a mother tongue or learning it as a second or foreign language find themselves learning about Islam and its culture as well.

Scientists develop machine learning tool to accurately identify Arabic dialects  in 22 Arabic-speaking countries
The official language in 22 countries spanning the Middle East, North Africa and the Arabian Peninsula, Arabic is one of the most spoken languages globally. Credit: Dr. Hala Georges, College of Fine Arts and Design, University of Sharjah.

With a totally different alphabet than English, the language has numerous sounds that are specific to its phonology. The charm of its sounds and characters bewilders countless foreign learners who aspire to speak it fluently. Though most learning of the Arabic language occurs in the standard formal variety, many foreign learners opt for colloquial or daily versions, particularly the spoken forms in currency in Egypt and Syria.

The authors say they didn’t face an easy task in their attempt when teaching computers to recognize different Arabic dialects just by listening to spoken words. They write, “The primary challenge is the development of a machine learning model capable of accurately identifying a wide range of Arabic dialects from audio recordings.

“This task is compounded by the inherent diversity and complexity of Arabic dialects, coupled with the technical challenges of audio processing and machine learning model optimization.”

The authors utilized datasets comprising more than 3,000 hours of audio segments collected from YouTube. The data includes 19 different dialects spoken in Algeria, Egypt, Iraq, Jordan, Saudi Arabia, Kuwait, Lebanon, Libya, Mauritania, Tunisia, Morocco, Oman, Palestine, Qatar, Sudan, Syria, the United Arab Emirates (U.A.E.), Bahrain and Yemen.

The results were impressive, said Prof. Elnagar, underscoring the model’s high accuracy in Arabic dialect identification regionally and at country levels. “Our model correctly identified regional dialects 97.29% of the time and specific country dialects 94.92% of the time.

Scientists develop machine learning tool to accurately identify Arabic dialects  in 22 Arabic-speaking countries
Arabic is a rich language with many regional dialects, and each one has its own unique vocabulary, expressions, and pronunciation. Credit: Dr. Hala Georges, College of Fine Arts and Design, University of Sharjah.

“What is remarkable is that we achieved this using only 29% of the training data typically required by other researchers. We have made our models publicly available so that other researchers and developers can use them to create better speech-related technologies for Arabic speakers.”

The project has the potential to enhance communication and accessibility for millions of Arabic speakers worldwide. Prof. Elnagar said the model’s ability to correctly identify a dialect can “improve voice-activated technologies like virtual assistants, translation services, and automated customer support systems.

“This not only bridges communication gaps between different Arabic-speaking regions but also contributes to making technology more inclusive and user-friendly for Arabic speakers.”

Despite the astounding results, Prof. Elnagar noted, the project can still be improved. For this purpose, the authors have made their system publicly available “online on a platform called HuggingFace, so others can access and build upon our work to improve Arabic language technologies.”

The research is the outcome of collaboration between Prof. Elnagar and three of his undergraduate students as part of a project to build a deep learning model for Arabic dialect identification from speech. The initial research results were first presented at the 15th Annual Undergraduate Research Conference on Applied Computing (URC) in 2024.

Scientists develop machine learning tool to accurately identify Arabic dialects  in 22 Arabic-speaking countries
With a totally different alphabet than English, the language has numerous sounds that are specific to its phonology. The charm of its sounds and characters bewilders countless foreign learners who aspire to speak it fluently. Credit: Dr. Hala Georges, College of Fine Arts and Design, University of Sharjah

“Developed by our dedicated students, the technology behind our system integrates cutting-edge methodologies and deep learning techniques. Expanding its functionality from text to audio signals sets it apart, providing a multi-modal approach to understanding and processing the Arabic language,” Prof. Elnagar said.

For student researcher Amr Barakat, the project “bridges a critical gap in language technology, enabling more inclusive and accurate communication for Arabic speakers worldwide. By leveraging advanced machine learning, we have created a model that not only excels in performance but also paves the way for future innovations in speech recognition.”

Another student researcher, Abdulla Aldhaheri, reported wide interest from the industry in the project, as it “holds the potential for widespread adoption, offering numerous benefits and improvements to various AI-driven language applications and services.”

Besides its high accuracy, the tool the authors have developed, unlike currently available models, requires less data and computational resources, rendering it accessible for wider use. This feature, according to the authors, was behind the industry’s interest in their work. They cited tech corporations like Microsoft and governmental bodies in Sharjah in the U.A.E. as being particularly enthusiastic about their work.

More information:
Amr Barakat et al, Arabic Dialect Identification from Speech, 2024 15th Annual Undergraduate Research Conference on Applied Computing (URC) (2024). DOI: 10.1109/URC62276.2024.10604557

Citation:
Scientists develop machine learning tool to accurately identify Arabic dialects in 22 Arabic-speaking countries (2024, October 7)
retrieved 7 October 2024
from https://techxplore.com/news/2024-10-scientists-machine-tool-accurately-arabic.html

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Arctic ozone reaches record high in positive step for climate

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Arctic ozone reaches record high in positive step for climate


Arctic ozone reaches record high in positive step for climate
Modeled representation of the Arctic ozone hole recovery in 2024. Credit: Michala Garrison, NASA Earth Observatory.

Earth’s ozone layer holes over polar regions, where the stratospheric ozone level is significantly depleted, have been a prevalent feature of climate change news in recent decades. Anthropogenic-sourced chlorofluorocarbons (CFCs) are the primary cause, released from household items such as coolants in fridges, air conditioners and spray cans. Restricting their use has been and remains paramount to ozone hole recovery as they have multi-decadal lifetimes in the atmosphere.

Policies to address ozone depletion, such as the 1987 international agreement of the Montreal Protocol, aim to stop the production and consumption of ozone-depleting substances in order to heal these ozone holes by 2045 and 2066 over the Arctic and Antarctic respectively. As such, since early 2000, levels of stratospheric ozone-depleting inorganic chlorine and bromine in the Arctic have declined, albeit rather slowly.

Amidst this bleak forecast, research published in Geophysical Research Letters has hinted at a brighter future to come. Dr. Paul Newman, Chief Scientist for Earth Scientists at NASA’s Goddard Space Flight Center, and colleagues identified March 2024 as a record high month for Arctic ozone since the 1970s, following a period of overall increase through winter 2023 to 2024.

Above-average ozone levels continued to persist through September 2024. This is significant as, previously, spring has been associated with ozone depletion when high CFC levels were coincident with large, cold, rotating low-pressure meteorological systems, known as polar vortices.

The research team highlight the significance of this research as preliminary evidence that CFC levels are now declining, in order to allow the ozone layer to begin its lengthy recovery. Dr. Newman said, “Ozone is the Earth’s natural sunscreen. Increased ozone is a positive story, since it’s good for the environment and encouraging news that the global Montreal Protocol agreement is producing positive results.”

To explore this change, Dr. Newman and colleagues investigated meteorological and satellite backscatter ultraviolet data to observe total column ozone (the total amount of ozone from Earth’s surface to the top of a particular column of the atmosphere) since 1979.

The March 2024 ozone average peaked at 477 Dobson units (DU), which is 6 DU higher than the previous record in March 1979 and 60 DU higher than the average for the study period (1979 to 2023). Daily record levels for the Arctic occurred for approximately half of the month, with March 20th seeing the maximum of 499 DU.

Arctic ozone reaches record high in positive step for climate
Stratospheric ozone levels across the winter of 2023 to 2024, compared to the climatological averages across the study interval of 1979 to 2024. Credit: Michala Garrison, NASA Earth Observatory.

They found that the lowermost portion of the stratosphere (10–20 km above Earth’s surface) experienced record high temperatures for 23 days of the month, coincident with these elevated ozone levels due to warmer weather systems moving up from the underlying troposphere into the stratosphere.

This contrasts with known extreme ozone depletion events in 1997, 2011 and 2020, which occurred during periods of prolonged polar vortices.

The causal mechanism for these anomalous temperature and ozone levels in March 2024 is attributed to enhanced winter eddy heat fluxes from atmospheric Rossby waves. These waves move into the stratosphere and cause a downward motion in the polar regions, leading to warmer polar temperatures.

The waves also slow the stratospheric polar night jet stream (polar vortex) around the Arctic, leading to air from the mid-latitudes converging on the pole, transporting more ozone into the region than normal.

“Arctic ozone is controlled by direct depletion of ozone by chlorine and bromine compounds and ozone transport,” Dr. Newman explains.

“For the former scenario, the temperatures were too warm for much depletion. For the latter case, waves that propagate into the stratosphere from the troposphere move ozone into the Arctic, warm the polar region, and decelerate the polar vortex. El Niño events and Siberian snow cover have been examined as controlling processes for ozone transport, but do not appear to have a major impact.

“The stronger than normal transport seems to be caused by a random weather year with significant propagation of Rossby waves into the stratosphere. It is likely that the declining levels of oxygen depleting substances and rising levels of carbon dioxide helped further elevate Arctic ozone to a record level.”

Given that carbon dioxide levels are still projected to increase in the years to come, Dr. Newman states that is “highly likely” that more of these record ozone events will continue to occur.

“Climate change is believed to be impacting the strength and stability of the stratospheric polar vortex. For example, changes in surface temperature and pressure that result from sea ice loss can increase generation of Rossby waves, resulting in a weaker and unstable polar vortex.

“In addition, global ozone is expected to slowly increase because of the Montreal Protocol. The combination of these two factors will create favorable conditions for higher polar ozone values.”

While the Artic and Antarctic overall respond similarly to the effect of Rossby waves, those in the Arctic are much stronger and therefore, ozone levels are higher than in the southern hemisphere, which experiences more pronounced ozone holes.

“The Arctic has a much stronger source of Rossby waves propagating upward into the stratosphere (quantified by the stronger eddy heat flux). Hence, the Arctic is warmer, has a weaker vortex, and much more ozone. Because the Antarctic has a very cold vortex that can contain the reactive chlorine, we have deep ozone holes each year,” Dr. Newman states.

Using this insight, coupled chemistry and climate models project a 10–30 DU increase in Arctic ozone from 2000 to 2025, resulting from reduced ozone depleting substances in the atmosphere and elevated greenhouse gas levels.

Furthermore, calculating an ultraviolet (UV) index for a clear sky at noon based upon this data, the 2024 Arctic ozone levels screen more UV, leading to a 5% reduction in the UV index compared to the average across the 1979 to 2023 study interval.

Ultimately, ozone recovery is paramount to protecting life on Earth, otherwise the increased incoming UV radiation from space can have a plethora of consequences, from reducing plant growth (affecting the ‘lungs of the Earth’ and agricultural food supply) and disrupting marine food chains by impacting growth or primary producers, to enhanced incidence of skin cancer and immune deficiency disorders in humans.

There is now hope that one day these ozone holes will heal.

More information:
Paul A. Newman et al, Record High March 2024 Arctic Total Column Ozone, Geophysical Research Letters (2024). DOI: 10.1029/2024GL110924

© 2024 Science X Network

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Arctic ozone reaches record high in positive step for climate (2024, October 7)
retrieved 7 October 2024
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Enzymes in spider venom have bioeconomic potential

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Enzymes in spider venom have bioeconomic potential


Enzymes in spider venom have bioeconomic potential
The venom cocktail of spiders—here the wolf spider Lycosa praegrandis—contains enzymes that could be of interest for bioeconomic applications. Credit: Louis Roth

As venomous animals, spiders use their chemical arsenal for prey capture or defense. Small neurotoxins target the central nervous system of their victims. While the toxins are intensively investigated, scientists at the LOEWE Center for Translational Biodiversity Genomics (TBG) in Hesse, Germany, have turned their attention to the enzymes also contained in the complex venom cocktail.

They discovered a large, previously overlooked diversity of these proteins that facilitate biochemical reactions. According to the researchers, these could be of great value for bioeconomic applications.

With about 52,000 species worldwide, spiders are particularly diverse and produce the most complex of all animal venoms: The venom of only a single species can contain more than 3,000 molecules. These belong mainly to the group of small neurotoxins and are used to overpower insects.

A team of researchers from the LOEWE Center TBG at the Fraunhofer Institute for Molecular Biology and Applied Ecology, branch of Bioresources (IME-BR) in Giessen, Germany, has now investigated the previously neglected components of spider venom and discovered something surprising.

In their study, they show that in addition to neurotoxins, the heavily investigated spider venom also contains a wide variety of enzymes. Their results have been published in the journal npj Biodiversity.

“In the past, a few pioneering studies suggested the presence of enzymes in spider venoms, but a targeted search for them has never been carried out. We took on this task and systematically screened the raw data of all so far venom-wise analyzed spiders for enzymes. We were able to show that there are in fact more than 140 different enzyme families in their venom,” explains study leader Dr. Tim Lüddecke, head of the Animal Venomics working group at the IME-BR in Giessen.

“This means, among others, that we have dramatically underestimated the chemical diversity of spider venoms so far, as all calculations of complexity are based on the neurotoxins alone.”

According to the authors, the results of the work not only enable new research approaches to better understand the evolution and function of spider venoms, but also open new perspectives for their use.

“Enzymes are key building blocks of the bioeconomy. They accelerate chemical reactions and are characterized by very low by-product formation, low energy consumption and biodegradability. They can therefore be used to create value in a highly sustainable way. Industry is therefore constantly looking for new sources of enzymes,” explains Josephine Dresler, Ph.D. student in the working group and first author of the study.

“Some of the enzymes we have identified could be used in detergents or waste management, for example, because of their fat-splitting or protein-degrading properties. They could make a significant contribution to a sustainable transformation there,” says Dresler.

The work of the Giessen scientists highlights the translational potential hidden in animal venoms, especially those of spiders. “So far, the spider venom community has focused exclusively on medical or agricultural applications. Our discovery opens up the possibility of establishing a completely new field of applied research,” explains Lüddecke.

“But we are only at the beginning, as less than 1% of all spider species have been studied for their venoms. I am confident that we will make more exciting discoveries in the remaining 99% of the world’s spider fauna.”

More information:
Josephine Dresler et al, Enlightening the toxinological dark matter of spider venom enzymes, npj Biodiversity (2024). DOI: 10.1038/s44185-024-00058-2

Provided by
Senckenberg Gesellschaft für Naturforschung

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Enzymes in spider venom have bioeconomic potential (2024, October 7)
retrieved 7 October 2024
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