Scientists

The relative risk of being born with a major heart defect is 36% in babies conceived using assisted reproductive techniques, such as in vitro fertilisation, compared to newborns not using these techniques, according to a study published in the European Heart Journal. The absolute risk was 1.84% versus 1.15%. The research, which included more than seven million babies born in Denmark, Finland, Norway and Sweden, also shows that the increased risk is especially associated with multiple births, which are more common in assisted reproduction.
 

Burying woody biomass in wooden vaults would allow carbon to be extracted and stored from the atmosphere, according to a study published in Science. The authors were inspired by an eastern red cedar log preserved underground for more than 3,700 years in Canada. The team proposes burying wood from sustainable sources in a domed wooden structure designed to extend the duration of carbon storage. The authors estimate that up to 10 gigatonnes of CO₂ could be sequestered annually using this technique.

Lithium, a material widely used for battery production, is typically extracted from rocks and concentrated brines, but these reserves are expected to run out by 2080. The alternative is to evaporate more diluted brines (such as seawater), but the traditional process is inefficient, polluting, and consumes large amounts of water. Two new studies published in Science propose two more viable and environmentally friendly alternative methods: the first uses a membrane that filters lithium through a transpiration system similar to that of plants, requiring only solar energy. The second combines electrodes to mimic a battery and move lithium from the brine (cathode) to fresh water (anode).

Prostate cancer screening tests using PSA (Prostate Specific Antigen) are associated with overdiagnosis, which calls into question their use. A clinical trial in men aged 50-60 years published in the journal NEJM has studied the possibility of adding an MRI test in those with an elevated PSA level and dispensing with biopsy if imaging finds no suspicious lesions. The results indicate that the procedure avoids more than half of clinically irrelevant cancer diagnoses that would not need treatment and only slightly increases the risk of failing to identify those that may become incurable. The authors recommend, on the basis of the study, to review the recommendations for such screening.

Rituximab and ocrelizumab are two antibodies with a similar mechanism of action that are used in the treatment of multiple sclerosis. Although the former had not shown benefits in primary progressive multiple sclerosis — which affects between 10% and 15% of patients — the latter is approved for this form of the disease. Now, a study conducted in France with more than 1,000 patients has found no benefits with either treatment, as they did not slow the progression of disability in these individuals. The results are published in the journal Neurology.

Newborns with Down syndrome, as they grow, face a higher risk of developing leukemia compared to those without the syndrome. An international team has sequenced the genes of more than 1.1 million cells from fetuses with and without Down syndrome, and it has discovered that the extra chromosome 21 they have alters the way DNA is packaged inside cells. According to the authors, whose research is published in Nature, this difference affects the regulation of certain genes and may contribute to the development of leukemia.

Large language models - Artificial Intelligence (AI) systems based on deep learning, such as the generative AI that is ChatGPT - are not as reliable as users expect. This is one of the conclusions of international research published in Nature involving researchers from the Polytechnic University of Valencia. According to the authors, in comparison with the first models and taking into account certain aspects, reliability has worsened in the most recent models, such as GPT-4 with respect to GPT-3.

More frequent and severe wildfires increase the temperature of the exposed land surface one year after the fire, according to an analysis of forest satellite data collected from 2003 to 2016. In recent decades, large wildfires have doubled or tripled their average size in eastern Spain, Canada, and western United States, as noted in the research published in Nature. The authors call for consideration of these effects on surface temperature when managing forests.

Canadian research analysing more than 863,000 births over almost a decade, including 806 surrogacy deliveries, concluded that the risk of severe maternal morbidity was 7.8% in gestational carriers, more than three times the risk of conception without assisted reproductive techniques and almost twice the risk in IVF pregnancies. The three most frequent complications were severe postpartum haemorrhage, severe pre-eclampsia and puerperal sepsis. The study is published in the Annals of Internal Medicine.

The Anthropocene began around 1952, according to a study based on geological records from 137 sites around the world, published in PNAS. The term ‘Anthropocene’ describes the period in Earth's history when human activities have drastically altered the planet; in March, an international scientific body dismissed it as an official geological epoch.