Comment

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 12:35pm

The case demonstrates how the science and justice systems can work together, and that it should prompt law reforms to create a more “science-sensitive legal system”. She and others are calling for the establishment of a criminal case review commission, similar to that in the United Kingdom, which can revisit cases when there are advances in the science and new evidence comes to light.

But despite praise for the process, researchers caution that science doesn’t necessarily make a case black and white. “When the science is really nuanced, and really new and evolving as this was, you still may not get consensus.

https://www.nature.com/articles/d41586-023-01871-8?utm_source=Natur...

Part 3

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Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 12:34pm

Vinuesa identified mutations in a gene called calmodulin 2 in Folbigg’s genome as well as in those of her two daughters, which could have explained the girls’ deaths. But that evidence was not enough to convince the commissioner of the first inquiry, who upheld Folbigg’s convictions. So in 2019, Vinuesa contacted the Australian Academy of Science, which gathered support to petition the governor of New South Wales to grant Folbigg a pardon, based on subsequent work by Overgaard and others that showed how the mutations impaired protein function.

At that stage, every other legal avenue had been exhausted. The governor ordered a new inquiry, and its commissioner, former state chief justice Thomas Bathurst, appointed the academy to act as a scientific adviser.

In that role, the academy recommended scientific expert witnesses and advised on the scope of expertise for each witness. The academy put forward some 30 researchers, around half of whom presented evidence at the inquiry. Other experts were also called by the prosecution and defence teams. The academy’s chief executive, Anna-Maria Arabia, says the inquiry heard “the most up-to-date science from the most qualified scientists, wherever they were in the world”. The expert witnesses were independent of both the prosecution and defence, says Arabia, and available for all parties to interrogate.

Peter Schwartz, a cardiologist at the Italian Auxological Institute in Milan, Italy, and a world leader in calmodulin mutations that cause sudden death, was one of the expert witnesses. He has advised on nearly 40 medico-legal cases, mostly in the United States, and says that having independent advice from the academy helped to ensure relevant experts presented world-leading evidence to the inquiry, instead of relying on one or two local experts. “I don’t recall ever having seen that in a trial of this kind,” he says, and “it goes to the credit of the Australian justice system.”

Overgaard says that he and other experts were given time to provide the necessary background so that lawyers thoroughly understood the science. On one occasion, he spent more than five hours explaining how mutations in the calmodulin protein could impair its function. The inquiry was also put on hold at one stage so that Overgaard and his team could update their evidence with results of further experiments they ran to address another expert’s questions, he says.

Part 2

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 12:34pm

Science was heard’: woman who was convicted of killing her children pardoned after inquiry

Kathleen Folbigg, who was jailed in Australia in 2003 over the sudden deaths of her four young children, has been pardoned and released in the wake of new scientific evidence.

Researchers and legal experts are applauding the role of an independent scientific adviser in an Australian judicial inquiry whose evidence led to the pardon and release of a woman sent to prison 20 years ago. Kathleen Folbigg, jailed in 2003 over the deaths of her four young children, walked free on 5 June after the inquiry concluded there was “reasonable doubt as to the guilt of Ms Folbigg for each of the offences for which she was originally tried”. Scientists involved in the inquiry are now calling for legal reform so that there is a formal process in Australia to present emerging scientific evidence.

“Science was heard in this case,” says Michael Toft Overgaard, a protein scientist at Aalborg University in Denmark who was an expert witness at the inquiry. “The whole case has been a bit surreal for us as scientists to be part of.”

Genetic evidence not available at the time of Folbigg’s conviction revealed that rare mutations in the protein calmodulin could have caused the deaths of her two daughters, and a neurogenetic disorder could have led to the death of one of her sons. Calmodulin controls calcium concentration in cells, and among other roles helps to regulate the heart’s contractions.

Regarding her pardon, “I’m so happy for her,” says geneticist Carola Vinuesa at the Francis Crick Institute in London. Vinuesa was approached by Folbigg’s lawyers in 2018 to sequence Folbigg’s genome and the genomes of her deceased children to see whether there was a genetic explanation for their sudden deaths, which occurred between 1989 and 1999.

Part 1

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 12:18pm

'AI doctor' better at predicting patient outcomes, including death

Artificial intelligence has proven itself useful in reading medical imaging and even shown it can pass doctors' licensing exams.

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Food safety: Cleaning with plasma instead of chemicals

A new method for cleaning conveyor belts in food production can replace the widely used disinfection chemicals. Plasma-treated water is effective against microbial contamination at a shorter exposure time and degrades without environmentally hazardous traces. These results were recently published in the journal Innovative Food Science and Emerging Technologies.

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 11:47am

How an earthquake becomes a tsunami

The movement between continental and oceanic plates at the bottom of the sea, so-called megathrust earthquakes, generates the strongest tremors and the most dangerous tsunamis. How and when they occur, however, has been poorly understood so far, since the ocean floor is difficult to access for measurements.

Thanks to new technologies, an international research team was able to take measurements to the nearest centimeter for the first time in an underwater-earthquake zone off Alaska. The researchers reported on their findings in the specialist journal Science Advances.

The Chignik earthquake on July 28, 2021, occurred 32 km below the seafloor off the coast of Alaska and, with a magnitude of 8.2, was the seventh strongest earthquake in US history. It occurred because the oceanic Pacific Plate is sliding past the continental North American Plate, thereby causing an enormous thrust.

In the sparsely populated region, the damage caused by the quake was limited. In general, however, such megathrust earthquakes have enormous destructive potential in the so-called subduction zone, i.e. the zone where oceanic and continental tectonic plates meet. In particular, tsunami waves can be generated. These are not very high at their place of origin, but hours later and many 100 or 1000 kilometers away, they can hit the coasts as a catastrophic tsunami and endanger many lives.

Researchers examined the seafloor off Alaska shortly before and about 2.5 months after the Chignik quake, using a global navigation satellite system (GNSS), an acoustic positioning system, and a robotic ship.

In the project, a key role was played by autonomous vessels , called wave gliders, that operate on the water surface.

The modern technology allowed measurements of the movements in the subduction zones to the nearest centimeter and thus a precise picture of the complicated slip processes and faults. Particular attention was paid to the shallow portions of the slip zones, as these are critical to whether or not a tsunami will occur. The measurements were taken at a water depth of 1,000 to 2,000 meters.

Benjamin A. Brooks et al, Rapid shallow megathrust afterslip from the 2021 M8.2 Chignik, Alaska earthquake revealed by seafloor geodesy, Science Advances (2023). DOI: 10.1126/sciadv.adf9299

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Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 11:15am

Remains of an extinct world of organisms discovered

Newly discovered biomarker signatures point to a whole range of previously unknown organisms that dominated complex life on Earth about a billion years ago. They differed from complex eukaryotic life as we know it, such as animals, plants and algae in their cell structure and likely metabolism, which was adapted to a world that had far less oxygen in the atmosphere than today.

An international team of  researchers now reports on this breakthrough for the field of evolutionary geobiology in the journal Nature.

The previously unknown "protosteroids" were shown to be surprisingly abundant throughout Earth's Middle Ages. The primordial molecules were produced at an earlier stage of eukaryotic complexity—extending the current record of fossil steroids beyond 800 and up to 1,600 million years ago. Eukaryotes is the term for a kingdom of life including all animals, plants and algae and set apart from bacteria by having a complex cell structure that includes a nucleus, as well as a more complex molecular machinery.

This "stem" represents the common ancestral lineage that was a precursor to all still living branches of eukaryotes. Its representatives are long extinct, yet details of their nature may shed more light on the conditions surrounding the evolution of complex life.

Although more research is needed to evaluate what percentage of protosteroids may have had a rare bacterial source, the discovery of these new molecules not only reconciles the geological record of traditional fossils with that of fossil lipid molecules, but yields a rare and unprecedented glimpse of a lost world of ancient life.

The competitive demise of stem group eukaryotes, marked by the first appearance of modern fossil steroids some 800 Million years ago, may reflect one of the most incisive events in the evolution of increasingly complex life.

Jochen Brocks, Lost world of complex life and the late rise of the eukaryotic crown, Nature (2023). DOI: 10.1038/s41586-023-06170-w. www.nature.com/articles/s41586-023-06170-w

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 10:27am

A documented case of a crocodile virgin birth

A team of entomologists and reptile specialists from Virginia Polytechnic Institute and State University, the Chiricahua Desert Museum, the Illinois Natural History Survey, Reptilandia Reptile Lagoon and Parque Reptilandia has documented a case of a virgin crocodile laying viable eggs. In their paper published in the journal Biology Letters, the group describes their surprise at the discovery of a clutch of eggs laid by an American crocodile who had been kept alone in an enclosure at Parque Reptilandia park in Costa Rica for 16 years prior to laying the eggs.

Prior research has found instances of "virgin birth"—a type of asexual reproduction in a species that normally reproduces sexually—in snakes, lizards, sharks and birds, but never in Crocodilia, an order that includes gharials, caimans, alligators and crocodiles. So the handlers at Parque Reptilandia were surprised to see a clutch of eggs in an enclosure hosting a single American crocodile.

Alligators are well known in North America, but crocodiles live there, too, in parts of Florida. They also live in Central and South America. They normally mate to reproduce, like most other reptiles, and lay eggs that later hatch. But now, it appears that they can reproduce asexually if need be.

The clutch of 14 eggs was discovered back in 2016. After handlers noted their arrival, they notified local specialists. The eggs were collected and taken to a lab for study, where researchers found that half of them were viable. The viable eggs were placed in an incubator with the hope of producing hatchlings.

None of the eggs produced any, unfortunately, leading the researchers to crack them open after three months to see what was going on. All of the eggs had progressed toward hatching, but only one actually resembled a fetus. A genetic study of the most advanced specimen revealed that it was nearly identical to its mother.

The research team notes that it was not surprising that none of the eggs were hatchable; eggs laid in such fashion rarely are. Now that virgin births have been documented in both birds and Crocodilia, it raises the question of whether pterosaurs and/or dinosaurs were able to do so, as well.

 Warren Booth et al, Discovery of facultative parthenogenesis in a new world crocodile, Biology Letters (2023). DOI: 10.1098/rsbl.2023.0129

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 10:06am

Synthetic species created without biochemistry operate according to Darwinian evolutionary principles

Imagine the possibility of life forms on other planets that don't resemble any on Earth. What might they look like, and why would they be so different?

This may be possible and the answer may be that they developed from a different type of chemistry.

Some researchers have studied how to produce synthetic living systems—without relying on biochemistry, or the chemistry that has enabled life on Earth. They have been have been trying to build a non-biochemical system, which unaided is capable of executing the essential properties common to all natural living systems. 

  One latest study, published last month in Cell Reports Physical Science, even finds such a system engaged in what Charles Darwin called "the struggle for life.

Researchers   created two synthetic models (or "species") and observed the ensuing competition between them. They figured out how to create non-biochemical but carbon-chemistry-based systems called protocells. These are made up of self-assembling polymer vesicles that emerge from a homogenous blend of smaller synthetic chemicals with no relation to living organisms. "These systems act like biochemical cells. They are born, metabolize what they need, grow, move, reproduce, and perhaps even evolve.

Now the researchers wanted to see whether these systems would operate according to the evolutionary principle of competitive exclusion. As we know from Darwin's work, this involves the struggle for survival—with the species with the greatest competitive advantage edging out the other when vying for resources.

They created two new species of protocells for this particular study—one with the advantage of light sensitivity, the other without. When the researchers watched how these systems behaved as they shared food in an illuminated environment, they saw that the light-sensitive "species" endured while the other did not. "It's the struggle for existence where the best-suited structure survived in its environment.

With these results, these researchers are  willing to go as far as to suggest that biochemicals are not essential to the struggle for life. This shows that non-biochemical carbon chemistry can lead to the extinction of the less 'fit' protocell species. 

Could there be chemistries beyond Earth capable of implementing the fundamental properties of life?

It's possible there are materials, which once on a planetary surface somewhere with appropriate conditions, could react chemically, self-organize, and perhaps do the things that this experiment shows.

Under the right circumstances, these materials may evolve from very simple chemistry into more complicated structures.

So these scientists think we should be very open about other forms of life elsewhere in the universe, and that they may not resemble life as we recognize it now.

Sai Krishna Katla et al, Competitive exclusion principle among synthetic non-biochemical protocells, Cell Reports Physical Science (2023). DOI: 10.1016/j.xcrp.2023.101359

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 11:49am

Data show no evidence that chronic disease treatment efficacies depend on number of comorbidities

Treatment efficacy for a broad range of chronic diseases does not differ depending on patients' comorbidities, according to a new study publishing June 6 in the open access journal PLOS Medicine.

There is often uncertainty about how treatments for single conditions should be applied to people who have multiple chronic conditions (multimorbidity). This confusion stems, in part, from the fact that people with multimorbidity are under-represented in randomized controlled trials, and trials rarely report whether the efficacy of treatment differs by the number of comorbidities or the presence of specific comorbidities.

In the new study, the researchers used existing data from 120 industry-sponsored randomized controlled phase 3 and 4 clinical trials carried out between 1990 and 2017. The dataset included a total of 128,331 participants and spanned 23 common long-term conditions, including asthma, diabetes, hypertension, osteoporosis, and migraine. For each trial as well as each treatment type spanning multiple trials, the team modeled whether there were any interactions between treatment efficacy and comorbidities.

Across trials, the percentage of participants with three or more comorbidities ranged from 2.3% (in allergic rhinitis trials) to 57% (in trials for systemic lupus erythematosus). Overall, the new study found no evidence of comorbidities modifying treatment efficacy across any of the 23 conditions studied. However, the authors noted that the trials were not designed to assess variation in treatment efficacy by comorbidity.

These findings suggest that for modest levels of comorbidities, this assumption is reasonable.

Hanlon P, Butterly EW, Shah AS, Hannigan LJ, Lewsey J, Mair FS, et al. Treatment effect modification due to comorbidity: Individual participant data meta-analyses of 120 randomised controlled trials, PLoS Medicine (2023). DOI: 10.1371/journal.pmed.1004176

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 9:12am

Ants inflict pain with neurotoxins

Researchers have shown for the first time that some of the world's most painful ant stings target nerves, like snake and scorpion venom. This research is published in Nature Communications.

Investigators discovered the ant neurotoxins while studying the Australian green ant and South American bullet ant which have stings that cause long-lasting pain.

These ant venoms target our nerve cells that send pain signals. Normally, the sodium channels in these sensory neurons open only briefly in response to a stimulus. However,  the ant toxins bind to the sodium channels and cause them to open more easily and stay open and active, which translates to a long-lasting pain signal.

Bullet ant stings can be painful for up to 12 hours and it's a deep drilling pain you feel in your bones with sweating and goosebumps, quite unlike the 10-minute impact of a typical bee sting.

The bullet ant was rated as having the most painful insect sting in the world by the late Dr. Justin Schmidt, an American entomologist who created a pain index of stinging insects.

These neurotoxins which target sodium channels are unique to ants. Ants developed their defensive neurotoxins to fend off predators during the time of the dinosaurs and have since become one of the most successful animal groups on Earth..

Samuel D. Robinson et al, Ant venoms contain vertebrate-selective pain-causing sodium channel toxins, Nature Communications (2023). DOI: 10.1038/s41467-023-38839-1

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