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551.
Danielle A. Jones Andrew J. Hansen Kevin Doherty Justin I. Paugh Scott J. Story 《Remote sensing of environment》2009,113(7):1346-1356
Many of the habitats and resources which influence ecological functioning within National Parks, and protected areas in general, are located outside of their borders in unprotected areas. Hence, land use and land cover changes in surrounding areas may substantially influence the natural resources within parks. The US National Park Service has recognized these threats and incorporated land use and land cover monitoring into its Inventory and Monitoring Program. The purpose of this paper is to provide a framework based on a conceptual approach for planning and implementing monitoring within this Program. We present a conceptual model, based on ecological theory, which illustrates how land use and land cover change impact park resources, and helps to identify monitoring indicators that will measure relevant attributes of land use and land cover change. We also discuss potential sources of data for quantifying indicators of land use and land cover change over time, including remote sensing data and ancillary spatial datasets. Finally, we describe steps for analyzing monitoring data so that the intensity and direction of changes in land use and land cover over time are quantified, as well as trends in the status of important park resources impacted by these changes. Integration of land use and land cover monitoring data and park resource data will allow for analysis of change from past to present, and can be used to project trends into the future to provide knowledge about potential land use and land cover change scenarios and ecological impacts. We illustrate our monitoring approach with an example from the Inventory and Monitoring Program's Greater Yellowstone Network. 相似文献
552.
Stokes Patricia D.; Lai Betty; Holtz Danielle; Rigsbee Elizabeth; Cherrick Danielle 《Canadian Metallurgical Quarterly》2008,34(3):640
Five experiments examined how practice early in skill acquisition affected variability and accuracy during skill retention (Experiments 1-5) and skill transfer (Experiments 3, 4, 5). Lag constraints required that each path from apex to base of a computer-generated pyramid display differ from some number (the lag) of immediately prior paths. Location constraints specified end points at which paths must exit the pyramid. In all experiments, an early optimal period for acquiring a variability level was identified. Both low and high levels of variability were sustained during retention; high levels facilitated transfer. The results suggest that (a) early practice that requires high variability sensitizes learners to changes in condition and (b) such perception-performance links facilitate transfer by activating appropriate alternative strategies/schema or initiating their construction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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554.
Alessandra Casagrande Ribeiro Edimar Aparecida Filomeno Fontes Camilo José Ramirez López Wassali Valadares Sousa Isabela Souza Gomes Edvaldo Barros Jane Sélia dos Reis Coimbra Sylvia do Carmo Castro Franceschini Danielle Aparecida Silva Maria Cristina Baracat-Pereira 《Molecular nutrition & food research》2023,67(12):2200308
555.
556.
Danielle Carpiné João Luiz Andreotti DagostinVitor Renan da Silva Luciana Igarashi-MafraMarcos Rogério Mafra 《Journal of food engineering》2013
This paper reports a study on the adsorption of the aroma component 2-phenylethanol from an aqueous solution onto granular activated carbon, derived from coconut husks, using batch and continuous (packed-bed column) systems. In the batch mode, the contact time required to attain the adsorption equilibrium was 90 min. The adsorption isotherms were evaluated at 20.0 °C, 30.0 °C and 40.0 °C. In the continuous mode, the effects of flow rate and bed length were studied. Experimental data showed that the breakthrough and exhaustion times decreased with higher flow rates and increased with higher packed beds. The adsorption in the fixed-bed column was more efficient under the following conditions: flow rate of 3.5 mL min−1 and bed length of 11 cm. Based on the data acquired, adsorption appears to represent a promising method for the recovery of 2-phenylethanol lost during the instant coffee production process. 相似文献
557.
Xinyu R. Ma Yugendar R. Alugubelli Yuying Ma Erol C. Vatansever Danielle A. Scott Yuchen Qiao Ge Yu Shiqing Xu Wenshe Ray Liu 《ChemMedChem》2022,17(1):e202100456
A number of inhibitors have been developed for the SARS-CoV-2 main protease (MPro) as potential COVID-19 medications but little is known about their selectivity. Using enzymatic assays, we characterized inhibition of TMPRSS2, furin, and cathepsins B/K/L by more than a dozen of previously developed MPro inhibitors including MPI1-9, GC376, 11a, 10–1, 10–2, and 10–3. MPI1-9, GC376 and 11a all contain an aldehyde for the formation of a reversible covalent hemiacetal adduct with the MPro active site cysteine and 10–1, 10–2 and 10–3 contain a labile ester to exchange with the MPro active site cysteine for the formation of a thioester. Our data revealed that all these inhibitors are inert toward TMPRSS2 and furin. Diaryl esters also showed low inhibition of cathepsins. However, all aldehyde inhibitors displayed high potency in inhibiting three cathepsins. Their determined IC50 values vary from 4.1 to 380 nM for cathepsin B, 0.079 to 2.3 nM for cathepsin L, and 0.35 to 180 nM for cathepsin K. All aldehyde inhibitors showed similar inhibition levels toward cathepsin L. A cellular analysis indicated high potency of MPI5 and MPI8 in inhibiting lysosomal activity, which is probably attributed to their inhibition of cathepsins. Among all aldehyde inhibitors, MPI8 shows the best selectivity toward cathepsin L. With respect to cathepsins B and K, the selective indices are 192 and 150, respectively. MPI8 is the most potent compound among all aldehyde inhibitors in cellular MPro inhibition potency and anti-SARS-CoV-2 activity in Vero E6 cells. Cathepsin L has been demonstrated to play a critical role in the SARS-CoV-2 cell entry. By selectively inhibiting both SARS-CoV-2 MPro and the host cathepsin L, MPI8 potentiates dual inhibition effects to synergize its overall antiviral potency and efficacy. Due to its high selectivity toward cathepsin L that reduces potential toxicity toward host cells and high cellular and antiviral potency, we urge serious consideration of MPI8 for preclinical and clinical investigations for treating COVID-19. 相似文献
558.
Bacteria coat themselves with a dense array of cell envelope glycans that enhance bacterial fitness and promote survival. Despite the importance of bacterial glycans, their systematic study and perturbation remains challenging. Chemical tools have made important inroads toward understanding and altering bacterial glycans. This review describes how pioneering discoveries from Prof. Carolyn Bertozzi's laboratory inspired our laboratory to develop sugar probes to facilitate the study of bacterial glycans. As described below, we used metabolic glycan labelling to install bioorthogonal reporters into bacterial glycans, ultimately permitting the discovery of a protein glycosylation system, the identification of glycosylation genes, and the development of metabolic glycan inhibitors. Our results have provided an approach to screen bacterial glycans and gain insight into their function, even in the absence of detailed structural information. 相似文献
559.
Ulf Betke Danielle Chazaro Mendoza Michael Scheffler 《International Journal of Applied Ceramic Technology》2023,20(1):204-212
Open-celled aluminum nitride ceramic foams were prepared by the polymer sponge replication technique involving aqueous dispersions of passivated AlN. The amount of the Y2O3 and Dy2O3 as sintering aid was varied, and the effects on the densification, microstructure formation, phase composition, and finally, the thermal conductivity were investigated. A typical thermal conductivity of 1.1 W m−1 K−1 was determined for foams at a porosity level of 94.3 vol.%, on average. This measured foam thermal conductivity was subsequently modeled using different porosity ↔ thermal conductivity relations considering the different hierarchical levels of porosity in these foams. From these models, the thermal conductivity of the bulk AlN strut material was determined, correlated with the strut microstructure and the phase composition, and compared to literature data. 相似文献