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Recent studies of the Middle and Upper Paleolithic in the northwestern Caucasus are focused on the research of relations between natural (climate and environment) and social (behavior and adaptations) factors that govern...

El Carpinterito Ocráceo (Picumnus nebulosus) se considera cercano a la amenaza en el orden internacional y amenazado en Argentina. En Argentina cuenta con pocos registros en las riberas del río Uruguay, en el extremo n...

The new charge-transfer complexes (CT) of eleven Schiff1 bases molecules as n-electron donors with the acceptor 1,4-naphthoquinone were studied spectrophotometrically in chloroform solution. The physical constants (a,b,C...

ABSTRACT Amphibians are excellent bioindicators because they are sensitive to chemical pollution and can indicate ecosystem changes due to the presence of or exposure to chemical compounds. Here we report evidence of the...

Anthropogenic climate change is one of the main threats to global biodiversity, with amphibians being among the most vulnerable vertebrate groups. In this context, the IUCN currently lists 69 species of Neotropical glass...

Through phylogenetic reconstruction this work analyzes the diversification of lanceolate points of the South Central Andes which began in the early Holocene and spanned the entire mid- Holocene. Based on a regional-scale...

Plants constitute the foundation of life on Earth, providing oxygen, food, and ecosystem services essential for human well-being. At the same time, they are among the most threatened components of biodiversity, with curr...

apria himalayana Griff. f. albovinosa Banziger & Hansen (Rafflesiaceae) is rare and endemic to northeastern Thailand, Vietnam, and Manipur, with a short flowering season ranging from late October to late November, due to...

Not all species are likely to be equally affected by habitat fragmentation; thus, we evaluated theeffects of size of forest remnants on trophically linked communities of plants, leaf-mining insects, and theirparasitoids....

As the key element for optical systems, polarization controllers with versatile functionalities are highly desired. Here, a CMOS-compatible polarization switch is proposed and realized by using a Mach–Zehnder interfero...

We compiled and analysed 16 historical photographic records of the Jaguar Panthera onca in the state of Santa Catarina before 1985, most of which have not been published in scientific literature. These records obtained f...

The Beijing–Tianjin–Hebei region of China features a unique topographic structure. Influenced by synoptic-scale systems, the region’s atmospheric strata over the plains are distinct. This study utilizes ground aero...

Rapid climatic changes and increasing human influence at high elevations around the world will have profound impacts on mountain biodiversity. However, forecasts from statistical models (e.g. species distribution models)...

Latest Maastrichtian climate change caused by Deccan volcanism has been invoked as a cause of mass extinction at the Cretaceous-Paleogene (K-Pg) boundary (~66.0 Ma). Yet late Maastrichtian climate and ecological changes...

Living on the edge: regional distribution and retracting range of the jaguar (Panthera onca).— To preserve biodiversity we need to understand how species are distributed and which aspects of the environment determine t...

Sloths and ground sloths (Xenarthra: Tardigrada) are among the most conspicuous mammals in the Cenozoic faunas of South America. During the late Pleistocene and the early Holocene, all the megafaunal xenarthrans became e...

Two biogeographical units are generally recognized in the present shelf area of Argentina: the Magellanian andArgentinian Provinces. The two provinces differ in their fossil record. The evolution of these provinces has b...

The proposed method of synthesis of CQDs on the basis of nanoporous carbon obtained from plant raw materials. It is established that in the short-wave region a band is registered, which is due to the exciton mechanism of...

Effective management of natural populations depends heavily on the capacity for understanding and predicting their habitat requirements. For endemic and threatened species like the mara (Dolichotis patagonum), this infor...

This study is as a follow up on earlier research which argued that Nnamdi Azikiwe was being accorded the position of a mere footnote in contemporary literature on Pan-Africanist thinking despite being one of the precurso...

Localized surface plasmon polaritons can confine the optical field to a single-nanometer-scale area, strongly enhancing the interaction between photons and molecules. Theoretically, the ultimate enhancement might be achi...

Este artigo mostra a situação atual de uso da Língua Geral Amazônica, as causas de seu desaparecimento de grande parte do Norte do Brasil e as iniciativas atuais para sua revitalização.This paper focuses the presen...

Topological edge state (TES) has emerged as a significant research focus in photonics due to its unique property of unidirectional transmission. This feature provides immunity to certain structural disorders or perturbat...

Cerca de 30% das espécies do grupo de sapos, rãs e pererecas sofrem ameaça de extinção, já tendo sido extintas 35 dessas espécies. Por apresentarem pele fina e permeável e, na maioria dos casos, fase larval que v...