Latest news with #PLoSOne
Scientific American
a day ago
- Health
- Scientific American
Pessimistic Dogs Are Better at Smelling Cancer—And Other Keys to Disease-Sniffing Success
Billy, a floppy-eared little beagle, darts around a platform sniffing a series of holes. Each hole contains a used surgical-type mask bearing a different human's distinct mix of scents. But her sharp nose is hunting for just one such combination: the one that signals cancer. Cancer can change a person's 'volatilome,' the unique set of volatile organic compounds found in breath, sweat, blood and urine. Billy and her cohort have learned to sniff out these subtle scent cues in masks worn by people with cancer diagnoses. Researchers are also studying how dogs can detect diseases such as COVID and malaria, as well as psychological conditions, including post-traumatic stress disorder. Scientists discovered dogs' powerful disease-smelling skills in 1989, when a dog detected cancer in its handler. But clinicians still do not routinely use dogs for diagnosis. Besides the obvious logistical challenges, dogs vary greatly in their olfactory accuracy. Researchers are increasingly finding that disease-sniffing prowess may come down to individual dogs' personality—and how well their handlers know them. New research efforts are focused on figuring out which dogs would be best for the job and on interpreting dogs' behaviors during a smell test. On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. Sharyn Bistre Dabbah, a veterinary scientist now at the University of Bristol in England, set out with colleagues at the U.K. charity Medical Detection Dogs to learn how the animals' personalities—especially their level of optimism or pessimism—affect disease-detection skills. Their results appeared recently in PLoS One. The researchers first showed the dogs what lay behind two screens at one end of a room: a 'positive' location with a tasty treat and a 'negative' one with an empty bowl. On subsequent visits to the room, the dogs typically bounded happily toward the former but trotted very slowly when they went to check out the latter—or simply didn't go there at all. The scientists then placed bowls behind two new screens between the positive and negative spots, and they classified the dogs as 'optimistic' or 'pessimistic' based on how quickly they investigated these new locations. Next, the team evaluated how accurately each dog could pick out a disease scent it was trained to detect among other smells. On average, the pessimistic dogs turned out to be more discerning. Pessimistic dogs are more cautious, and 'a more cautious dog might be better at not making mistakes,' Dabbah says. Other personality traits also play a role, says Clara Wilson, who researches disease- and stress-sniffing dogs at the University of Pennsylvania. Dogs that enjoy the thrill of a hunt—and thrive while searching for missing people or hidden bombs—might find sniffing through disease samples again and again rather repetitive. 'We want a dog that doesn't get frustrated. They [should] find it rewarding, even though it may be less exciting,' Wilson explains. Handlers' interpretations of dog behavior can also skew detection outcomes, says Akash Kulgod, co-founder of Dognosis, the Bengaluru-based start-up that trained Billy. Instead of teaching dogs to perform a specific behavior such as sitting or barking when they pick up an assigned scent—a process that takes extra time and can lead to dogs 'lying' for treats—Kulgod and his team directly analyze each dog's natural body language. Based on how confidently the dogs move, as analyzed with computer vision–based machine-learning tools, the team can spot successful detections. 'One of our dogs sniffs and then very confidently somersaults to go to the feeder,' Kulgod says. 'They each have their own unique quirks—but all of it can be quantified because it's all related to this reward expectation that you have from the past sessions.' In a pilot study with 200 test samples involving 10 cancer types, presented at this year's American Society of Clinical Oncology conference, Dognosis dogs detected 96 percent of cancers. Next, the Dognosis team will scale up its study with 1,500 test samples. Doctors currently diagnose many kinds of cancers by using a combination of blood tests and biopsies. Researchers are always on the lookout for less invasive methods—including options directly involving our canine companions, as well as electronic noses inspired by them. Dogs can currently outperform electronic sniffers. But this primacy may not last, according to Andreas Mershin, chief science officer at the Boston-based start-up He and his colleagues are developing electronic noses to sniff urine samples for prostate cancer and other diseases. If machine olfaction eventually surpasses dogs' abilities, it could help tackle the scalability problem—and give the animals a break. Mershin's team put mammalian smell receptors on an electronic chip and used machine-learning algorithms to interpret the output. The technique focuses on broader patterns among detected molecules rather than categorizing them individually. Dogs don't tick off a list of molecules in their heads, either; they just 'know' what cancer smells like. This helps them to sense it accurately no matter which organ it is from or what the patient ate before giving their breath sample. 'The dogs can generalize. They don't care about the font in which you write the scent; they just interpret it correctly,' Mershin says. In a study published in PLoS One, Mershin and his team used machine-learning models to spot and analyze patterns of different odorants in urine samples from confirmed prostate cancer patients. Their findings, which built on work with diagnosis data from Medical Detection Dogs, suggest that focusing on this type of 'scent character' might work as a scalable alternative to dogs, even if it's currently much slower. Meanwhile, back on the test platform, floppy-eared Billy quickly detects the subtle scent of cancer in one of the masks she has been sniffing—and confidently bounds back to get her reward. Such tests show strong potential, says postdoctoral researcher Amritha Mallikarjun of the University of Pennsylvania: 'The dogs, because of their amazing sense of smell and detection capabilities, are demonstrating to us what technology could look like 10 to 15 years from now.'
Irish Independent
27-06-2025
- Science
- Irish Independent
Archaeologists in Poland discover what could be world's oldest boomerang
©UK Independent Today at 00:30 A mammoth tusk artefact discovered in a Polish cave could be Europe's earliest example of a boomerang and even the oldest tool of its kind in the world, archaeologists have said. The tusk was found along with what seemed like a human little finger or toe bone fossil at the Oblazowa cave in Poland, and it could be nearly 40,000 years old, according to a study published in the journal PLoS One.
The Independent
26-06-2025
- Science
- The Independent
World's oldest boomerang may have been found - but not in Australia
A mammoth tusk artefact discovered in Poland 's Obłazowa cave could be Europe 's earliest boomerang and potentially the world's oldest tool of its kind. The ivory artefact, estimated to be nearly 40,000 years old, was found alongside what appears to be a human little finger or toe bone fossil, according to a study published in the journal PLoS One. Unlike most ancient boomerangs, typically found in Australia, are made of wood, this discovery highlights the resourcefulness of early Homo sapiens ancestors using ivory. Experiments suggest the artefact could function as a non-returning boomerang, similar to Australian types, and markings provide cultural context for early Homo sapiens in Europe. Archaeologists speculate the human digit fossil found with the boomerang may indicate a shamanistic ritual, offering insights into early human technological innovation and symbolic behaviours.
The Hindu
16-06-2025
- Science
- The Hindu
A whale tooth's journey from the sea to a Copper Age pit
When archaeologists were digging a new library site at Valencina de la Concepción in southwest Spain in 2018, they uncovered an unusual item: half of a large sperm-whale tooth lying in a 4,000-year-old pit. Because nothing like it had ever been reported from Copper-Age Iberia, the team ran a bevy of tests to learn where it could have come from and how it ended up in the pit. Thus, based on evidence of marine boring and beach-root damage, the team unravelled the tooth's long journey from a sperm whale's mouth and to a settlement deep inland, offering en route a timeline of coastal processes four millennia ago. Their findings were recently published in PLoS One. The team shot overlapping photos with a camera and processed them to build a detailed 3D model that could be rotated on a screen, allowing tiny marks to be examined without handling the fragile specimen. Then team members used a digital microscope to reveal surface scratches, drill holes, and biological bores smaller than a millimetre wide. The team also unraveled four kinds of small tunnels and grooves: made by sponges, marine worms, grazing snails, and burrowing barnacles. They also mapped bite marks left behind by sharks. The shape of the root — thick with a single point and light enamel — matched contemporary sperm whales. The original tooth was estimated to have been 20-25 cm long, meaning the whale was an adult. Radiocarbon dating of the other animal bones and pottery in the pit revealed it was dug in about 2500-2400 BC. In this way, the team reported that after the whale died, the tooth stayed on the seabed long enough for sponges, worms, snails and barnacles to bore into it and for sharks to scavenge the carcass. Later, water currents rolled it around and partially buried it in sand. Someday, a storm or very high tide finally tossed the tooth onto a nearby shore. While buried in beach sand, plant roots etched new channels and a limestone crust formed on its surface. Humans of the Copper Age then picked it up, probably because it looked exotic and valuable, and pressed several chisels or awls into the break edge to split pieces off pieces, probably to use in ornaments. Eventually, the people placed the trimmed tooth in a pit about a metre wide and deep along with broken dishes, stone tools, and animal bones. The archaeologists didn't find any human bones inside and thus concluded the pit to be a 'structured deposition', meant to remove precious items from everyday use. This is the only sperm-whale tooth found in Copper-Age Spain and only the second in the Western Mediterranean of similar date. Its discovery thus widened the list of rare and prized materials — including elephant ivory, ostrich eggshells, and rock crystals — circulating at Valencina at this time. The burial also showed that coastal objects, even from gigantic sea creatures never seen alive inland, held symbolic power for communities engaged predominantly in farming.
The Australian
12-06-2025
- Business
- The Australian
Study backs Rhythm's colorectal risk model
Rhythm publishes peer-reviewed study validating its next-generation colorectal cancer risk assessment model Proprietary geneType assessment enhanced and cross-validated using data from nearly 400,000 individuals in UK Biobank Next generation geneType design continues focus on usability and simplicity, while providing superior performance Special Report: Rhythm Biosciences has published a peer-reviewed study in PLoS One validating its next-generation colorectal cancer risk assessment model, marking a major step forward in predictive cancer diagnostics. Rhythm Biosciences (ASX:RHY) said the study detailed updates and improvements to its proprietary geneType colorectal cancer risk assessment, which was enhanced and cross-validated using data from nearly 400,000 individuals in the UK Biobank. Rhythm said the article titled 'Colorectal cancer risk prediction using a simple multivariable model' described creation and validation of a new risk model that incorporated sex-specific factors and outperformed current models. The company said as colorectal cancer was a disease associated with many environmental and lifestyle risk factors, the study focused on expanding its geneType model beyond the two primary risk factors – family history and polygenic risk. Watch: Inside ColoSTAT's road to market Key findings of study Rhythm said the study delivered several key findings, most notably development of the enhanced risk model that incorporated three additional risk factors. These factors were selected for their strong associations with colorectal cancer and ease of use in a clinical setting, improving the model's predictive performance over standard family history assessments. The company said the most impactful risk factors were identified and integrated into an updated geneType risk model, which was then tested using data from the UK Biobank. Rhythm said other key findings included: Commitment to improvement – The study highlighted the importance of including clinical and lifestyle factors in multifactorial diseases like colorectal cancer. Commercial application – The new model was designed with commercial clinical applications in mind, minimising the number of risk factors while maximising predictive accuracy. Sex-specific factors – Incorporating sex-specific risk factors enhances model performance across diverse populations. Superior performance – A multivariable risk assessment is shown to be superior to standard of care of family history assessment in its ability to predict risk of developing colorectal cancer. 'Significantly improve stratified screening' Rhythm director of scientific affairs Dr Erika Spaeth said publishing the findings in PLoS One underscored its commitment to advancing cancer risk prediction. 'Our new multifactorial model outperforms previous methods based solely on polygenic risk and family history,' she said. 'By integrating clinical and lifestyle factors, we enhance our prediction accuracy for colorectal cancer. 'We're excited about these results and confident that this model will significantly improve stratified screening in the population." This article was developed in collaboration with Rhythm Biosciences, a Stockhead advertiser at the time of publishing. This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.
