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1.
PLoS One ; 16(4): e0250183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914765

RESUMO

Globally, forest-savanna mosaic landscapes are of significant conservation importance but have been widely impacted by human land-use. We studied how restoration, through cessation of long-term cattle grazing impacts (i) forest regeneration; (ii) forest understory structure and composition; and (iii) populations and diversity of large mammals and nocturnal birds, within naturally patchy gallery forests in the Beni Savannas of Bolivia. Comparing grazed and restored sites, we assessed the abundance and composition of tree functional types at different life stages (seedlings, saplings and adults), with focus on the region's key palm species Attalea princeps (motacú). Additionally, we surveyed habitat structure and composition in the shrub and ground-layer, and monitored occurrence and encounter rates of large mammals and nocturnal birds along dusk and evening transects. We found evidence of lower recruitment of motacú palms on the grazed site and lower potential for natural motacú regeneration. Principal Components Analysis revealed forests on grazed sites had simpler, more open shrub-layers and altered ground-layer structure and composition including increased bare ground. Mammal species richness was greater on the restored site, and there were more declining, globally threatened and site-unique species. Species richness was similar for nocturnal birds within forests on both the grazed and restored site, but nearly all species tended to be encountered more frequently on the restored site. Our results suggest cattle negatively impact forest regeneration and alter the structure and composition of the shrub and ground layer with potential consequences for the diversity and abundance of wildlife. Our study represents one of only a handful completed in the Beni region of Bolivia to date. The Beni is currently under pressure from widespread, largely unregulated cattle ranching. Our results thus provide vital evidence to support development of restoration and conservation policy, and its integration with rangeland management in this threatened and critically understudied region.


Assuntos
Arecaceae/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Recuperação e Remediação Ambiental/métodos , Animais , Animais Selvagens , Arecaceae/metabolismo , Biodiversidade , Aves , Bolívia , Ecossistema , Florestas , Mamíferos , Árvores
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 3717-3720, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30441177

RESUMO

Bedside monitors in hospital intensive care units (ICUs) are known to produce excessive false alarms that could desensitize caregivers, resulting in delayed or even missed clinical interventions to life-threatening events. Our previous studies proposed a framework aggregating information in monitor alarm data by mining frequent alarm combinations (i.e., SuperAlarm) that are predictive to clinical endpoints, such as code blue events, in an effort to address this critical issue. In the present pilot study, we hypothesize that sequential deep learning models, specifically long-short term memory (LSTM), could capture time-depend features in continuous alarm sequences preceding code blue events and these features may be predictive of these endpoints. LSTM models are trained from continuous alarm sequences in various window lengths preceding code blue events, and the preliminary results showed the best performance reached an AUC of 0.8549. With the selection of optimal cutoff threshold, the 2-hour window model achieved 85.75% sensitivity and 72.61% specificity, respectively.


Assuntos
Reanimação Cardiopulmonar , Alarmes Clínicos , Aprendizado Profundo , Monitorização Fisiológica , Projetos Piloto
3.
Sci Rep ; 1: 176, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22355691

RESUMO

We investigated the properties of clonally-expanded mouse hair follicle stem cells (HF-SCs) in culture. The expansion method, suppression of asymmetric cell kinetics (SACK), is non-toxic and reversible, allowing evaluation of the cells' asymmetric production of differentiating progeny cells. A tight association was discovered between non-random sister chromatid segregation, a unique property of distributed stem cells (DSCs), like HF-SCs, and a recently described biomarker, Lgr5. We found that nuclear Lgr5 expression was limited to the HF-SC sister of asymmetric self-renewal divisions that retained non-randomly co-segregated chromosomes, which contain the oldest cellular DNA strands, called immortal DNA strands. This pattern-specific Lgr5 association poses a potential highly specific new biomarker for delineation of DSCs. The expanded HF-SCs also maintained the ability to make differentiated hair follicle cells spontaneously, as well as under conditions that induced cell differentiation. In future human cell studies, this capability would improve skin grafts and hair replacement therapies.


Assuntos
Núcleo Celular/metabolismo , Segregação de Cromossomos , Folículo Piloso/citologia , Receptores Acoplados a Proteínas G/metabolismo , Células-Tronco/citologia , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem da Célula , Cromátides/metabolismo , Citocalasina D/farmacologia , DNA/análise , Células Epidérmicas , Regulação da Expressão Gênica , Camundongos , Pele/patologia
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