You are here

News Feeds

DNA analysis rewrites the stories of people buried in Pompeii

New Scientist Feed - Thu, 11/07/2024 - 8:00am
Genetic analysis of five individuals preserved as plaster casts in the ruins of Pompeii contradicts established beliefs about the people and their relationships
Categories: Science

Readers’ wildlife photos

Why Evolution is True Feed - Thu, 11/07/2024 - 6:15am

If you have good wildlife photos, please send them in, as we always need more.  Today we have a word-and-picture post on butterflies contributed by Athayde Tonhasca Júnior. His words are indented, and you can enlarge the photos by clicking on them:

Fluttering souls

We may be unsympathetic to celebrities who moan about the encumbrances of being gorgeous, but not the Greek princess Psyche. Her striking beauty sent the goddess of love Aphrodite (Venus to the Romans) into a not so loving fit of jealousy. She devised a cunning plan; to dispatch her son Eros (Cupid) on a mission to make Psyche fall in love with the ugliest, wickedest man he could find. But Aphrodite should have taken a hint from her son’s name: Eros spoiled mum’s revenge by falling in love with Psyche. That didn’t work too well for the princess; she became separated from Eros and fell into the clutches of a resentful Aphrodite, who imposed upon her a series of terrible tasks. After many twists and turns worthy of a Mexican telenovela – you can read it all in Metamorphoses – the lovers were reunited. Zeus, Heaven’s Big Cheese, took pity on Psyche. He made her immortal and gave her in marriage to Eros. A happy ending.

Psyche’s tribulations and eventual redemption spoke of mortals’ aspirations, so in her newly acquired divine status, the princess became the goddess of the human soul. For the ancient Greeks, a dying person would breathe out his or her soul, which would fly to the underworld in the form of flickering shadows or spirits. In his History of Animals, Aristotle (384–322 BC) wrote that a butterfly’s cocoon was like a tomb, and the adult insect emerging from it was like the soul fluttering away from a human body after death. It’s no surprise then that the Greek word ψυχή (Psykhe) was used for ‘soul’ and ‘butterfly’. The representation of the soul as a butterfly was an appropriate symbol of the fragility and shortness of life, and that connection explains why goddess Psyche was often represented as a butterfly or as a maiden with butterfly wings.

Psyche, by Pietro Tenerani (1789-1869) © Paolobon140, Wikimedia Commons:

Butterflies have much more to do with humans than merely representing the wanderings of our soul. Their colours and wing patterns, their gentleness and fragility and amazing life cycles have long enthralled naturalists, artists and writers. More books have been written about butterflies than any other insect. Butterflies don’t share the PR problem facing wasps, spiders and other invertebrates that are commonly lumped together as creepy crawlies. Most people like butterflies. Sometimes the attraction is excessive: over-collecting by amateurs, naturalists, and biologists menaces many butterfly species.

The butterfly hunter, by Carl Spitzweg (1808–1885) © Museum Wiesbaden, Wikimedia Commons:

Butterflies are among our commonest and certainly most flamboyant garden visitors. We see them gracefully hopping from flower to flower, probing them with their conspicuous proboscis (tubular, flexible and elongated mouthparts specialised for sucking) for a sip of nectar. So, reasonably, we may assume these plant-insect associations are evidence for psychophily (pollination by butterflies). But that would be a too-hasty conclusion.

Psykhe brought us words such as psychology, psychedelic, psychopath, psycho, psychosomatic, psychomotor and psychophily – the latter illustrated by this pollen-carrying skipper butterfly © Raju Kasambe, Wikimedia Commons:

 

It has long been known that flower visitation does not necessarily result in pollination. That will happen only when pollen grains from the stamen (the male part of the plant) are transferred to the stigma (the female part). But many factors interfere with this process: the visitor may only collect nectar, bypassing the all-important pollen. If pollen is collected, it may be dropped before reaching a receptive stigma, eaten, or taken away to feed the visitors’ brood. Pollen grains passively attached to the visitors’ body may be too few, or located on the wrong part of the body so that it does not contact a stigma. For a variety of reasons, most flower visitations have no bearing of plant fertilisation.

Butterflies are largely nectar drinkers, tapping flowers’ abundant reserves of sugars and amino acids. Some species get their nutrition from ripe or rotten fruit, tree sap, wet soil, animal carcasses and even tears. But with the exception of pollen-munching Heliconius spp. (Young & Montgomery, 2020), butterflies stick to a liquid diet. They rely on their proboscis, an intricate feeding apparatus that works as a drinking straw ranging in length from around 6 mm to a record 52.7 mm for the immaculate ruby-eye skipper (Damas immaculata) (Bauder et al., 2014).

The coiled proboscis of a butterfly © Atudu, Wikimedia Commons:

Pollen is inconsequential to most butterflies. They don’t collect it willingly and their bodies are not adapted to unintentionally transport significant amounts of pollen grains like bees and flies. And that is a problem for plants: they invest a lot of energy producing nectar to attract pollinators. If a visitor goes away with a bellyful of nectar but no pollen, the plant has been a victim of nectar theft (when visitors take nectar without pollinating the flower). Butterflies as a group may have evolved to be nectar thieves, which from the plants’ point of view is nothing short of parasitism (Wiklund et al., 1979). This form of larceny is not restricted to butterflies: bees, flies, birds and most other visitors will steal nectar if given the opportunity (Irwin et al., 2010). But most of the 20,400 or so described species of butterflies don’t compensate their thievery by pollinating their victims.

Butterfly visitors are detrimental or indifferent for a wide range of flowering plants. But, as invariably is the case in biology, things are not simple or straightforward. Butterflies are abundant flower visitors and some species are long distance flyers, therefore with great potential for pollen dispersal. Some plants have not let these traits go to waste: they adopted psychophily as their main or sometimes only means of sexual reproduction. A few plants do that by producing reproductive structures that facilitate pollen transfer by butterfly wings. Others, like the Carthusian pink (Dianthus carthusianorum), hide their nectar at the bottom of narrow, tubular flowers that exclude most visitors, but not butterflies with long proboscises. While moths can take nectar while hovering over a flower, butterflies need to land to feed. The Carthusian pink obliges them with flowers shaped with a flat rim, which is a convenient landing platform for butterflies. This European plant is found in dry, grassy habitats of altitudes of up to 2,500 m, and it depends entirely on butterflies for pollination (Bloch et al., 2006).

Carthusian pink:

In some cases, butterflies intending to commit thievery have the table turned around on them, so that the would-be cheaters become the cheated.

Crucifix orchids (Epidendrum spp.) comprise over 1,400 species distributed from the southeastern United States to northern Argentina. This group of plants is highly diverse morphologically and ecologically, but most investigated species share one feature: a dry cuniculus. This structure is concealed in the column (the fused reproductive parts characteristic of orchids) and normally functions as a nectar reservoir. The majority of crucifix orchids have no nectar to bargain, but that doesn’t deter a range of butterflies. Probably attracted by the orchid’s scents, they probe the flower’s column and cuniculus in search of a non-existent reward. Ending up empty-handed is not the butterflies’ sole unpleasant surprise: the floral tube is narrow and bent, so that a visitor has to struggle to retract its proboscis. This temporary detainment – which could last for over one hour – increases the chances of a butterfly leaving the flower with pollinia (a blob of pollen) attached to its proboscis. This stratagem works very well for the orchids, so that butterflies and some day-flying moths are their only or main pollinators.

(A) Epidendrum densiflorum inflorescence; (B) Dissected flower and detail of column; (C) Flower in longitudinal section, showing the empty cuniculus © Silveira et al., 2023.

Butterflies do not belong to pollinators’ Premier League, but the Carthusian pink, crucifix orchids and several other plants demonstrate that psychophily is not that rare. Butterflies fly over large distances, are attracted to a variety of plants and make repeated visits to flowers. These features must compensate for some of their shortcomings, and we surely have much more to discover about their role in plant reproduction.

Themisto amberwing (Methona themisto), an orchid pollinator © Evaldo Resende, Wikimedia Commons:

Categories: Science

#Oatzempic – The viral oat-based alternative to Ozempic?

Science-based Medicine Feed - Thu, 11/07/2024 - 5:00am

Can the Oatzempic diet deliver Ozempic-like weight loss?

The post #Oatzempic – The viral oat-based alternative to Ozempic? first appeared on Science-Based Medicine.
Categories: Science

Power grids supplied largely by renewable sources experience lower intensity blackouts

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 2:18pm
New research into the vulnerability of power grids served by weather-dependent renewable energy sources (WD-RESs) such as solar and wind paints a hopeful picture as various countries around the globe attempt to meet their climate emissions targets -- with the research showing grids with high penetration of WD-RESs tend to have reduced blackout intensities in the US.
Categories: Science

Scientists calculate predictions for meson measurements

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 2:18pm
Calculations of charge distribution in mesons provide benchmark for experimental measurements and validate widely used 'factorization' method for imaging the building blocks of matter.
Categories: Science

Ancient Egyptians shaped sheep's horns – and we don't know why

New Scientist Feed - Wed, 11/06/2024 - 2:05pm
The earliest evidence of livestock with modified horns has been discovered in ancient Egypt – sheep skulls with horns that point in unnatural directions suggest humans forced them to grow that way
Categories: Science

Knots made in a weird quantum fluid can last forever

New Scientist Feed - Wed, 11/06/2024 - 12:15pm
Shapes created by vortices in water often fall apart, but an odd quantum fluid made from ultracold atoms could support vortex knots that never lose their knottiness
Categories: Science

A new approach to modeling complex biological systems

Computers and Math from Science Daily Feed - Wed, 11/06/2024 - 11:27am
Biological engineers developed a computational approach to extracting useful information from large biological datasets. They showed they could unravel interactions that determine how the immune system responds to tuberculosis vaccination and infection.
Categories: Science

Pathogens which cling to microplastics may survive wastewater treatment

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 11:26am
Wastewater treatment fails to kill several human pathogens when they hide out on microplastics in the water, according to a new study.
Categories: Science

'Shallow' sports and 'deep' social hierarchies: Not all pecking orders are created equal

Computers and Math from Science Daily Feed - Wed, 11/06/2024 - 11:26am
Researchers have added a new dimension to the mathematics used to predict the outcomes of all manner of competitions, including sports, games and social hierarchies in both humans and animals.
Categories: Science

New PFAS testing method created

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 11:26am
Researchers have discovered a new way to detect per- and polyfluoroalkyl substances (PFAS) in water. This marks an important step forward in creating testing devices that are simpler, more cost-effective, faster and generally more accessible than existing methods.
Categories: Science

A Space Walking Robot Could Build a Giant Telescope in Space

Universe Today Feed - Wed, 11/06/2024 - 10:28am

The Hubble Space Telescope was carried to space inside the space shuttle Discovery and then released into low-Earth orbit. The James Webb Space Telescope was squeezed inside the nose cone of an Ariane 5 rocket and then launched. It deployed its mirror and shade on its way to its home at the Sun-Earth L2 Lagrange point.

However, the ISS was assembled in space with components launched at different times. Could it be a model for building future space telescopes and other space facilities?

The Universe has a lot of dark corners that need to be peered into. That’s why we’re driven to build more powerful telescopes, which means larger mirrors. However, it becomes increasingly difficult to launch them into space inside rocket nose cones. Since we don’t have space shuttles anymore, this leads us to a natural conclusion: assemble our space telescopes in space using powerful robots.

New research in the journal Acta Astronautica examines the viability of using walking robots to build space telescopes.

The research is “The new era of walking manipulators in space: Feasibility and operational assessment of assembling a 25 m Large Aperture Space Telescope in orbit.” The lead author is Manu Nair from the Lincoln Centre for Autonomous Systems in the UK.

“This research is timely given the constant clamour for high-resolution astronomy and Earth observation within the space community and serves as a baseline for future missions with telescopes of much larger aperture, missions requiring assembly of space stations, and solar-power generation satellites, to list a few,” the authors write.

While the Canadarm and the European Robotic Arm on the ISS have proven capable and effective, they have limitations. They’re remotely operated by astronauts and have only limited walking abilities.

Recognizing the need for more capable space telescopes, space stations, and other infrastructure, Nair and his co-authors are developing a concept for an improved walking robot. “To address the limitations of conventional walking manipulators, this paper presents a novel seven-degrees-of-freedom dexterous End-Over-End Walking Robot (E-Walker) for future In-Space Assembly and Manufacturing (ISAM) missions,” they write.

An illustration of the E-walker. The robot has seven degrees of freedom, meaning it has seven independent motions. Image Credit: Mini Rai, University of Lincoln.

Robotics, Automation, and Autonomous Systems (RAAS) will play a big role in the future of space telescopes and other infrastructure. These systems require dexterity, a high degree of autonomy, redundancy, and modularity. A lot of work remains to create RAAS that can operate in the harsh environment of space. The E-Walker is a concept that aims to fulfill some of these requirements.

The authors point out how robots are being used in unique industrial settings here on Earth. The Joint European Torus is being decommissioned, and a Boston Dynamics Spot quadruped robot is being used to test its effectiveness. It moved around the JET autonomously during a 35-day trial, mapping the facility and taking sensor readings, all while avoiding obstacles and personnel.

The Boston Dynamics Spot robot spent 35 days working autonomously on the Joint European Torus. Here, Spot is inspecting wires and pipes at the facility at Culham, near Oxford (Image Credit: UKAEA)

Using Spot during an industrial shutdown shows the potential of autonomous robots. However, robots still have a long way to go before they can build a space telescope. The authors’ case study could be an important initial step.

Their case study is the hypothetical LAST, a Large Aperture Space Telescope with a wide-field, 25-meter primary mirror that operates in visible light. LAST is the backdrop for the researchers’ feasibility study.

LAST’s primary mirror would be modular, and its piece would have connector ports and interfaces for construction and for data, power, and thermal transfer. This type of modularity would make it easier for autonomous systems to assemble the telescope.

LAST would build its mirror using Primary Mirror Units (PMUs). Nineteen PMUs make up a Primary Mirror Segment (PMS), and 18 PMSs would constitute LAST’s 25-meter primary mirror. A total of 342 PMUs would be needed to complete the telescope.

This figure shows how LAST would be constructed. 342 Primary Mirror Units make up the 18 Primary Mirror Segments, adding up to a 25-meter primary mirror. (b) shows how the center of each PMU is found, and (c) shows a PMU and its connectors. Image Credit: Nair et al. 2024.

The E-Walker concept would also have two spacecraft: a Base Spacecraft (BSC) and a Storage Spacecraft (SSC). The BSC would act as a kind of mothership, sending required commands to the E-Walker, monitoring its operational state, and ensuring that things go smoothly. The SSC would hold all of the PMUs in a stacked arrangement, and the E-Walker would retrieve one at a time.

The researchers developed eleven different Concept of Operations (ConOps) for the LAST mission. Some of the ConOps included multiple E-walkers working cooperatively. The goals are to optimize task-sharing, prioritize ground-lifting mass, and simplify control and motion planning. “The above-mentioned eleven mission scenarios are studied further to choose the most feasible ConOps for the assembly of the 25m LAST,” they explain.

This figure summarizes the 11 mission ConOps developed for LAST. (a) shows assembly with a single E-walker, (b) shows partially shared responsibilities among the E-walkers, (c) shows equally shared responsibilities between E-walkers, and (d) shows assembly carried out in two separate units, which is the safer assembly option. Image Credit: Nair et al. 2024.

Advanced tools like robotics and AI will be mainstays in the future of space exploration. It’s almost impossible to imagine a future where they aren’t critical, especially as our goals become more complex. “The capability to assemble complex systems in orbit using one or more robots will be an absolute requirement for supporting a resilient future orbital ecosystem,” the authors write. “In the forthcoming decades, newer infrastructures in the Earth’s orbits, which are much more advanced than the International Space Station, are needed for in-orbit servicing, manufacturing, recycling, orbital warehouse, Space-based Solar Power (SBSP), and astronomical and Earth-observational stations.”

The authors point out that their work is based on some assumptions and theoretical models. The E-walker concept still needs a lot of work, but a prototype is being developed.

It’s likely that the E-walker or some similar system will eventually be used to build telescopes, space stations, and other infrastructure.

The post A Space Walking Robot Could Build a Giant Telescope in Space appeared first on Universe Today.

Categories: Science

Hydrogels harness sunlight: A step closer to artificial photosynthesis

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 10:26am
Researchers designed bioinspired hydrogels capable of using sunlight to produce hydrogen and oxygen from water. Hydrogels contain polymer networks that facilitate energy conversion, offering a breakthrough approach to generating renewable hydrogen energy. This research shows how polymer-based systems could revolutionize sustainable energy production.
Categories: Science

A smart 'insect screen' for sun protection and cool comfort

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 10:26am
A research team unveils a next-generation transparent cooling film using the principles of radiative cooling.
Categories: Science

Use of 'genetic scissors' carries risks

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 10:26am
The CRISPR tool is capable of repairing the genetic defect responsible for the immune disease chronic granulomatous disease. However, researchers have now shown that there is a risk of inadvertently introducing other defects.
Categories: Science

Investigating performance limitations in cost-effective materials for perovskite solar cells

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 10:26am
Researchers investigated the internal properties of low-cost materials used in perovskite solar cells, which are attracting attention for their high efficiency, using electron spin resonance (ESR) to analyze these materials at a microscopic level. The results clarify the underlying causes for reduced device performance, despite high local charge mobility, offering critical insights for designing improved solar cells.
Categories: Science

Earthquake prediction techniques lend quick insight into strength, reliability of materials

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 10:25am
Materials scientists can now use insight from a very common mineral and well-established earthquake and avalanche statistics to quantify how hostile environmental interactions may impact the degradation and failure of materials used for advanced solar panels, geological carbon sequestration and infrastructure such as buildings, roads and bridges.
Categories: Science

Scientists unveil strategies to make self-driven vehicles passenger-friendly

Computers and Math from Science Daily Feed - Wed, 11/06/2024 - 10:24am
Automated vehicles promise to improve urban mobility, but passenger trust remains a challenge. Providing timely, passenger-specific explanations for automated vehicle decisions can bridge this trust gap. To address this, researchers introduced TimelyTale, a dataset designed to capture real-world driving scenarios and passenger explanation needs. It would be nice to see this multimodal dataset approach for in-vehicle explanation generation improving passengers' trust and confidence in automated vehicles.
Categories: Science

Interstellar methane as progenitor of amino acids?

Space and time from Science Daily Feed - Wed, 11/06/2024 - 10:24am
Gamma radiation can convert methane into a wide variety of products at room temperature, including hydrocarbons, oxygen-containing molecules, and amino acids, reports a research team. This type of reaction probably plays an important role in the formation of complex organic molecules in the universe -- and possibly in the origin of life. They also open up new strategies for the industrial conversion of methane into high value-added products under mild conditions.
Categories: Science

Detecting evidence of lung cancer in exhaled breath

Matter and energy from Science Daily Feed - Wed, 11/06/2024 - 10:24am
Exhaled breath contains chemical clues to what's going on inside the body, including diseases like lung cancer. And devising ways to sense these compounds could help doctors provide early diagnoses -- and improve patients' prospects. Researchers report developing ultrasensitive, nanoscale sensors that in small-scale tests distinguished a key change in the chemistry of the breath of people with lung cancer.
Categories: Science

Pages

Subscribe to The Jefferson Center  aggregator