148 research outputs found
Tipificación en Gutierrezia (Asteraceae, Astereae)
During the course of the revision of the South American species of Gutierrezia, we have detected names that require typification. After the analysis of the protologues and the herbarium specimens, we designated eight lectotypes and one neotype for nine names of the Gutierrezia genus and we assigned the category of holotype to one specimen. A detailed discussion is provided for each case.Durante el transcurso de la revisión de las especies sudamericanas de Gutierrezia, hemos podido hallar nombres que requieren tipificación. Luego del análisis de los protologos y especímenes de herbario, hemos designado ocho lectótipos y un neótipo para nueve nombres del género Gutierrezia. Además, se asignó la categoría de hólotipo a un especimen. Se provee una discusión detallada para cada nombre
The AquaGranda digital community memory: activating awareness about climate risk
This study aims to explore how vulnerable communities, scientists, and artists can collaborate to construct digital community memories to excavate opinion spaces related to socio-natural events, creating a shared and inclusive ground for mutual understanding and collective action. The proposed approach combines web archeology and digital artivism to construct community memories that can be used for social activation in relation to climate change. The research draws on participatory and community-based research techniques, citizen-science approaches, and digital methods to collect dispersed community-memory fragments and create an expressive space for the diverse perspectives and needs of the affected populations. It emphasises the importance of inclusivity and non-polarizing approaches for reconstructing and interpreting narrative streams that propagate in the physical and virtual world, and for representing, through digital art, extreme events and their societal impact. To illustrate the proposed approach, the AquaGranda project is here presented as a case study of community memory related to an extreme event: the high tides that occurred in Venice in November 2019
MicroEvol : Evolution et dynamiques des populations pyrénéennes : Vallée de Vicdessos
National audienceFinancé par l’Observatoire Hommes Milieux (OHM) du Haut-Vicdessos et conduit de 2010 à 2018 par des anthropologues biologistes dans une démarche interdisciplinaire incluant des collaborations avec historiens démographes et généticiens des populations, le programme intitulé « MicroEvolution : Evolution et dynamiques des populations humaines pyrénéennes » vise à étudier la dynamique biologique à moyen et long terme des populations de la Haute Vallée du Vicdessos. Concrètement, l’objectif est de voir comment les environnements socio-écologiques (ressources, contextes socio-économiques, maladies..) ont modulé la dynamique démographique (migrations, choix du conjoint, mortalité et naissances..) des populations de la Vallée. Deux approches complémentaires sont menées, une première s’appuyant sur les archives historiques (registres d’état civil, statistiques) des villages de la Haute Vallée pour une analyse essentiellement centrée sur le XIX° siècle et le début du XX° siècle. Une analyse de génétique des populations et des marqueurs uni-parentaux (ADN mitochondrial et du Chromosome Y) pour une analyse sur le long terme du peuplement de la Vallée prise dans son ensemble (basse et haute Vallée du Vicdessos). Le séminaire de l'OHM des 7 et 8 janvier 2020 a été l’occasion de présenter les principaux résultats de cette recherche, en particulier du second volet « long terme ». Il a mis en lumière la nécessité de confronter ces résultats à la lumière des proxi obtenus dans le cadre des autres projets de l’OHM Vicdessos, notamment des données paléo-environnementales
Avaliação da produtividade agrícola da cana-planta e cana-soca sob diferentes espaçamentos entre plantas para produção de açúcar e etanol.
Para avaliar a influência da variação do espaçamento entre linhas na produtividade e na qualidade da cana-de-açúcar para produção de etanol e açúcar foi instalado um experimento em gleba sob reforma na área agrícola da Usina Renuka - Unidade Madhu. Tal unidade sucroalcooleira, localizada na Bacia do Médio Rio Tietê, com área agrícola no Município de Guaiçara, SP, é uma das cinco maiores do mundo, com capacidade de moagem de 6,5 milhões de toneladas de cana-de-açúcar por ano.bitstream/item/146625/1/BolPesq40-Silva.pd
High-content screen in human pluripotent cells identifies miRNA-regulated pathways controlling pluripotency and differentiation
Background: By post-transcriptionally regulating multiple target transcripts, microRNAs (miRNAs or miR) play important biological functions. H1 embryonic stem cells (hESCs) and NTera-2 embryonal carcinoma cells (ECCs) are two of the most widely used human pluripotent model cell lines, sharing several characteristics, including the expression of miRNAs associated to the pluripotent state or with differentiation. However, how each of these miRNAs functionally impacts the biological properties of these cells has not been systematically evaluated. Methods: We investigated the effects of 31 miRNAs on NTera-2 and H1 hESCs, by transfecting miRNA mimics. Following 3-4 days of culture, cells were stained for the pluripotency marker OCT4 and the G2 cell-cycle marker Cyclin B1, and nuclei and cytoplasm were co-stained with Hoechst and Cell Mask Blue, respectively. By using automated quantitative fluorescence microscopy (i.e., high-content screening (HCS)), we obtained several morphological and marker intensity measurements, in both cell compartments, allowing the generation of a multiparametric miR-induced phenotypic profile describing changes related to proliferation, cell cycle, pluripotency, and differentiation. Results: Despite the overall similarities between both cell types, some miRNAs elicited cell-specific effects, while some related miRNAs induced contrasting effects in the same cell. By identifying transcripts predicted to be commonly targeted by miRNAs inducing similar effects (profiles grouped by hierarchical clustering), we were able to uncover potentially modulated signaling pathways and biological processes, likely mediating the effects of the microRNAs on the distinct groups identified. Specifically, we show that miR-363 contributes to pluripotency maintenance, at least in part, by targeting NOTCH1 and PSEN1 and inhibiting Notch-induced differentiation, a mechanism that could be implicated in na\uefve and primed pluripotent states. Conclusions: We present the first multiparametric high-content microRNA functional screening in human pluripotent cells. Integration of this type of data with similar data obtained from siRNA screenings (using the same HCS assay) could provide a large-scale functional approach to identify and validate microRNA-mediated regulatory mechanisms controlling pluripotency and differentiation
Fazenda Nata da Serra, Serra Negra, SP: descrição de caso de sucesso na produção orgânica de leite.
Em 2007, a primeira visita da equipe da Embrapa Pecuária Sudeste a Fazenda Sula (Nata da Serra), em Serra Negra (SP), revelou três fatos marcantes que acabaram por definir toda a trajetória tecnológica descrita em detalhes neste livro. Primeiro, foi uma surpresa muito positiva visitar um engenheiro agrônomo, produtor de hortaliças e frutas orgânicas, tecnificado, com desempenho, produtividade e qualidade superior aos produtos convencionais. Os tomates e morangos eram maravilhosos e honestamente não era isso que estava em nosso imaginário como modelo de produtor orgânico, certamente por pura ignorância nossa
Performance and automation of ancient DNA capture with RNA hyRAD probes
DNA hybridization-capture techniques allow researchers to focus their sequencing efforts on preselected genomic regions. This feature is especially useful when analys- ing ancient DNA (aDNA) extracts, which are often dominated by exogenous environ- mental sources. Here, we assessed, for the first time, the performance of hyRAD as an inexpensive and design-free alternative to commercial capture protocols to obtain authentic aDNA data from osseous remains. HyRAD relies on double enzymatic re- striction of fresh DNA extracts to produce RNA probes that cover only a fraction ofthe genome and can serve as baits for capturing homologous fragments from aDNA li- braries. We found that this approach could retrieve sequence data from horse remains coming from a range of preservation environments, including beyond radiocarbon range, yielding up to 146.5-fold on-target enrichment for aDNA extracts showing ex- tremely low endogenous content (20%¿30%), while the fraction of endogenous reads mapping on- and off-target was relatively insensi- tive to the original endogenous DNA content. Procedures based on two instead of a single round of capture increased on-target coverage up to 3.6-fold. Additionally, we used methylation-sensitive restriction enzymes to produce probes targeting hypo- methylated regions, which improved data quality by reducing post-mortem DNA dam- age and mapping within multicopy regions. Finally, we developed a fully automated hyRAD protocol utilizing inexpensive robotic platforms to facilitate capture process- ing. Overall, our work establishes hyRAD as a cost-effective strategy to recover a set of shared orthologous variants across multiple ancient samples.This project received funding from: the University Paul Sabatier IDEX Chaire d’Excellence (OURASI); the CNRS Programme de Recherche Conjoint (PRC); the CNRS International Research Project (IRP AMADEUS); the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 797449; the Russian Foundation for Basic Research, project No. 19-59-15001 “Horses and their importance in the life of the ancient population of Altai and adjacent territories: interdisciplinary research and reconstruction”; and the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement 681605)
Widespread horse-based mobility arose around 2200 bce in Eurasia
Horses revolutionized human history with fast mobility1. However, the timeline between their domestication and their widespread integration as a means of transport remains contentious2–4. Here we assemble a collection of 475 ancient horse genomes to assess the period when these animals were first reshaped by human agency in Eurasia. We find that reproductive control of the modern domestic lineage emerged around 2200 bce, through close-kin mating and shortened generation times. Reproductive control emerged following a severe domestication bottleneck starting no earlier than approximately 2700 bce, and coincided with a sudden expansion across Eurasia that ultimately resulted in the replacement of nearly every local horse lineage. This expansion marked the rise of widespread horse-based mobility in human history, which refutes the commonly held narrative of large horse herds accompanying the massive migration of steppe peoples across Europe around 3000 bce and earlier3, 5. Finally, we detect significantly shortened generation times at Botai around 3500 bce, a settlement from central Asia associated with corrals and a subsistence economy centred on horses6, 7. This supports local horse husbandry before the rise of modern domestic bloodlines
Glycosaminoglycan and Proteoglycan Biotherapeutics in Articular Cartilage Protection and Repair Strategies: Novel Approaches to Visco?supplementation in Orthobiologics
The aim of this study is to review developments in glycosaminoglycan and proteoglycan research relevant to cartilage repair biology and in particular the treatment of osteoarthritis (OA). Glycosaminoglycans decorate a diverse range of extracellular matrix and cell associated proteoglycans conveying structural organization and physico‐chemical properties to tissues. They play key roles mediating cellular interactions with bioactive growth factors, cytokines, and morphogenetic proteins, and structural fibrillar collagens, cell interactive and extracellular matrix proteoglycans, and glycoproteins which define tissue function. Proteoglycan degradation detrimentally affects tissue functional properties. Therapeutic strategies have been developed to counter these degenerative changes. Neo‐proteoglycans prepared from chondroitin sulfate or hyaluronan and hyaluronan or collagen‐binding peptides emulate the interactive, water imbibing, weight bearing, and surface lubricative properties of native proteoglycans. Many neo‐proteoglycans outperform native proteoglycans in terms of water imbibition, matrix stabilization, and resistance to proteolytic degradation. The biospecificity of recombinant proteoglycans however, provides precise attachment to native target molecules. Visco‐supplements augmented with growth factors/therapeutic cells, hyaluronan, and lubricin (orthobiologicals) have the capacity to lubricate and protect cartilage, control inflammation, and promote cartilage repair and regeneration of early cartilage lesions and may represent a more effective therapeutic approach to the treatment of mild to moderate OA and deserve further study
Shedding Light on The Role of Keratinocyte-Derived Extracellular Vesicles on Skin-Homing Cells
Extracellular vesicles (EVs) are secretory lipid membranes with the ability to regulate cellular functions by exchanging biological components between different cells. Resident skin cells such as keratinocytes, fibroblasts, melanocytes, and inflammatory cells can secrete different types of EVs depending on their biological state. These vesicles can influence the physiological properties and pathological processes of skin, such as pigmentation, cutaneous immunity, and wound healing. Since keratinocytes constitute the majority of skin cells, secreted EVs from these cells may alter the pathophysiological behavior of other skin cells. This paper reviews the contents of keratinocyte-derived EVs and their impact on fibroblasts, melanocytes, and immune cells to provide an insight for better understanding of the pathophysiological mechanisms of skin disorders and their use in related therapeutic approaches
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