Dark matter is an elusive type of matter that does not emit, absorb or reflect light, interacting very weakly with ordinary matter. These characteristics make it impossible to detect using conventi... Read more Dark matter is an elusive type of matter that does not emit, absorb or reflect light, interacting very weakly with ordinary matter. These characteristics make it impossible to detect using conventional technologies used by physicists to study matter particles. Show less

Aux Émirats arabes unis, les travaux pour construire Khazna Solar PV, la plus grande centrale solaire au monde, ont débuté cette année. Doté de capacités de production et de stockage hors norme, ce... Read more Aux Émirats arabes unis, les travaux pour construire Khazna Solar PV, la plus grande centrale solaire au monde, ont débuté cette année. Doté de capacités de production et de stockage hors norme, ce projet représente une avancée majeure pour la transition énergétique. Show less

A stunning new image from the ISS reveals a galaxy next door exploding with stellar activity.

L’enquête a permis de démontrer que le conducteur avait bien fait usage de protoxyde d’azote et qu’il conduisait manifestement à vitesse excessive, selon le parquet. L’accident a tué une femme et b... Read more L’enquête a permis de démontrer que le conducteur avait bien fait usage de protoxyde d’azote et qu’il conduisait manifestement à vitesse excessive, selon le parquet. L’accident a tué une femme et blessé les trois autres occupants du véhicule. Show less

![CDATA[The bookmakers have had their say on who could succeed the Portuguese at Old Trafford.]]

Over the holiday period, the Guardian leader column is looking ahead at the themes of 2026. Today we examine how the White House’s war on vaccines has left the future of a key technology uncertain ... Read more Over the holiday period, the Guardian leader column is looking ahead at the themes of 2026. Today we examine how the White House’s war on vaccines has left the future of a key technology uncertain and up for grabsThe late scientist and thinker Donald Braben argued that 20th-century breakthroughs arose from scientists being free to pursue bold ideas without pressure for quick results or rigid peer review. The rapid development of Covid-19 vaccines seemed to validate his claim: emergency conditions sped up trials, relaxed regulatory sequencing and encouraged scientists to share findings before peer review. Out of that sprang one of the great scientific success stories of our age: mRNA vaccines. These use synthetic genetic code to train the immune system to defend itself against viruses. Katalin Karikó and Drew Weissman, whose work enabled the mRNA Covid vaccine, went on to win the Nobel prize. Their breakthrough suggests that loosening traditional constraints could accelerate major scientific advances.The extensive scientific and logistic infrastructure built during that period is now occupied with turning the technology towards other diseases: flu, HIV and even cancer. Until very recently, the US, which put more than $10bn into mRNA development, appeared primed to reap the scientific and commercial rewards. Despite the deregulatory zeal that birthed mRNA, the second Trump administration has rejected it. Instead, it has been remarkably steady in its commitment to the radical anti-science and anti-vaccine agenda of the US health secretary, Robert F Kennedy Jr. He has spent the past year undermining and outright sabotaging the US’s own success. Over the summer, the US Department of Health and Human Services announced a “coordinated wind-down” of federal funding for mRNA research, cancelling an additional $500m in funding for 22 projects.Do you have an opinion on the issues raised in this article? If you would like to submit a response of up to 300 words by email to be considered for publication in our letters section, please click here. Continue reading... Show less

Hypervelocity stars have, since the 1920s, been an important tool that allows astronomers to study the properties of the Milky Way galaxy, such as its gravitational potential and the distribution o... Read more Hypervelocity stars have, since the 1920s, been an important tool that allows astronomers to study the properties of the Milky Way galaxy, such as its gravitational potential and the distribution of matter. Now astronomers from China have made a large-volume search for hypervelocity stars by utilizing a special class of stars known for their distinct, regular, predictable pulsation behavior that makes them useful as distance indicators. Show less

Graptopetalum sinaloensis R. Vega,  in Vega Aviña, Vargas et Pío León, 2020.  DOI: 10.21829/abm127.2020.1550   Researchgate.net/publicati... Read more Graptopetalum sinaloensis R. Vega,  in Vega Aviña, Vargas et Pío León, 2020.  DOI: 10.21829/abm127.2020.1550   Researchgate.net/publication/345773954ABSTRACT Background and Aims: The genus Graptopetalum includes about 20 species of branched or acaulescent rosette herbs that grew in little accessible semiarid environments (mountains or ravines) of Mexico and Arizona. The authors have developed continuous work to document the flora of Sinaloa and the present article reports a taxonomic novelty in the genus Graptopetalum.Methods: In the municipality of Culiacán, Sinaloa, Mexico, a small population of plants of the genus Graptopetalum with dry inflorescences was found in June 2013, and some plants were collected and cultivated, they flowered in March. Plants with flowers were collected from the same location in February 2014. Morphological data of wild and cultivated material were compared with that of herbarium specimens, literature, and cultivated Graptopetalum species; and it was determined that collected material is a new species for science.Key results: The new taxon Graptopetalum sinaloensis, section Graptopetalum, is described. Its differences and similarities with the closest species are discussed. Moreover, a new and updated dichotomous key is provided for the eight species of this section.Conclusions: Graptopetalum sinaloensis is endemic to south-central Sinaloa, Mexico. It grows in very localized areas, on rocky walls of streams and at the foot of hills, forming small populations in reduced areas of 5 to 10 m2. Graptopetalum sinaloensis differs from other Graptopetalum species from Sinaloa by its 5-merous flowers vs. G. rusbyi with 6-7-merous ones, and by its paniculate inflorescence, vs. G. occidentale with cymose ones. Additionally, the geographical distribution of the three species does not overlap.Key words: Byrnesia, flora of Sinaloa, Graptopetalum rusbyi, Graptopetalum occidentale, Sedum, tropical deciduous forest.Graptopetalum sinaloensis R. Vega. A. plantas colectadas en campo (28.II.2014); B. y C. inflorescencias y planta en floración en medio silvestre (3.III.2019); D. planta sin floración registrada (7.XI.2018). Fotos de Rito Vega-Aviña (A) y Juan Fernando Pío-León (B-D).Graptopetalum sinaloensis R. Vega, sp. nov.Rito Vega Aviña, Francisco Delgado Vargas and Juan Fernando Pío León. 2020. Graptopetalum sinaloensis (Crassulaceae), una nueva especie de Sinaloa, México [Graptopetalum sinaloensis (Crassulaceae), A New Species from Sinaloa, Mexico]. Acta Botanica Mexicana. 127; e1550. DOI: 10.21829/abm127.2020.1550  Researchgate.net/publication/345773954_Graptopetalum_sinaloensis_una_nueva_especie_de_Sinaloa_Mexico facebook.com/ActaBotanicaMexicana/posts/3190615780955458 Show less