Applied environmental stresses to enhance the levels of polyphenolics in leaves of hawthorn plants

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72331/1/j.1399-3054.2004.00332.x.pd

Hydrogels Based on Chitosan and Chitosan Derivatives for Biomedical Applications

Chitosan (CS) is a polymer obtained from chitin, being this, after the cellulose, the most abundant polysaccharide. The fact of (i) CS being obtained from renewable sources; (ii) CS to possess capability for doing interactions with different moieties being such capability dependent of pH; (iii) plenty of possibilities for chemical modification of CS; and (iv) tuning the final properties of CS derivatives makes this polymer very interesting in academic and technological points of view. In this way, hydrogels based on CS and on CS derivatives have been widely used for biomedical applications. Other important technological applications can be also cited, such as adsorbent of metals and dyes in wastewater from industrial effluents. In pharmaceutical field, hydrogels based on CS are often used as drugs’ and proteins’ carrier formulations due to the inherent characteristics such as the biocompatibility, nontoxicity, hydrophilicity, etc. This chapter is an attempt for updating and joining the plenty of available information regarding the preparation, characterization, and biomedical application of hydrogels based on chitosan and chitosan derivatives. More than 260 references are provided, being the majority of them published in the last 10 years

Impact of the spatial resolution of satellite remote sensing sensors in the quantification of total suspended sediment concentration: A case study in turbid waters of Northern Western Australia

The impact of anthropogenic activities on coastal waters is a cause of concern because such activities add to the total suspended sediment (TSS) budget of the coastal waters, which have negative impacts on the coastal ecosystem. Satellite remote sensing provides a powerful tool in monitoring TSS concentration at high spatiotemporal resolution, but coastal managers should be mindful that the satellite-derived TSS concentrations are dependent on the satellite sensor's radiometric properties, atmospheric correction approaches, the spatial resolution and the limitations of specific TSS algorithms. In this study, we investigated the impact of different spatial resolutions of satellite sensor on the quantification of TSS concentration in coastal waters of northern Western Australia. We quantified the TSS product derived from MODerate resolution Imaging Spectroradiometer (MODIS)-Aqua, Landsat-8 Operational Land Image (OLI), and WorldView-2 (WV2) at native spatial resolutions of 250 m, 30 m and 2 m respectively and coarser spatial resolution (resampled up to 5 km) to quantify the impact of spatial resolution on the derived TSS product in different turbidity conditions. The results from the study show that in the waters of high turbidity and high spatial variability, the high spatial resolution WV2 sensor reported TSS concentration as high as 160 mg L-1 while the low spatial resolution MODIS-Aqua reported a maximum TSS concentration of 23.6 mg L-1. Degrading the spatial resolution of each satellite sensor for highly spatially variable turbid waters led to variability in the TSS concentrations of 114.46%, 304.68% and 38.2% for WV2, Landsat-8 OLI and MODIS-Aqua respectively. The implications of this work are particularly relevant in the situation of compliance monitoring where operations may be required to restrict TSS concentrations to a pre-defined limit

The MicrOmega Investigation Onboard Hayabusa2

International audienc

Middle-status conformity revisited: The interplay between achieved and ascribed status

Decisions about conforming to or deviating from conventional practices in a field is an important concern of organization and management theory. The position that actors occupy in the status hierarchy has been shown to be an important determinant of these decisions. The dominant hypothesis, known as middle-status-conformity, posits that middle-status actors are more likely to conform to conventional practices than high- and low-status actors do. We challenge this hypothesis by revisiting its fundamental assumptions and developing a theory where actors’ propensity to conform based on their achieved status further depends on their ascribed status that actors inherit from their social group. Specifically, we propose that middle-status conformity applies only to actors who have a sense of security, based on their high ascribed status. For actors with low ascribed status, we propose that high-and low-status actors show greater conformity than middle-status actors. We test our hypotheses using data from the U.S. symphony orchestras from 1918 to 1969

Methane bursts as a trigger for intermittent lake-forming climates on post-Noachian Mars

Lakes existed on Mars later than 3.6 billion years ago, according to sedimentary evidence for deltaic deposition. The observed fluviolacustrine deposits suggest that individual lake-forming climates persisted for at least several thousand years (assuming dilute flow). But the lake watersheds’ little-weathered soils indicate a largely dry climate history, with intermittent runoff events. Here we show that these observational constraints, although inconsistent with many previously proposed triggers for lake-forming climates, are consistent with a methane burst scenario. In this scenario, chaotic transitions in mean obliquity drive latitudinal shifts in temperature and ice loading that destabilize methane clathrate. Using numerical simulations, we find that outgassed methane can build up to atmospheric levels sufficient for lake-forming climates, if methane clathrate initially occupies more than 4% of the total volume in which it is thermodynamically stable. Such occupancy fractions are consistent with methane production by water–rock reactions due to hydrothermal circulation on early Mars. We further estimate that photochemical destruction of atmospheric methane curtails the duration of individual lake-forming climates to less than a million years, consistent with observations. We conclude that methane bursts represent a potential pathway for intermittent excursions to a warm, wet climate state on early Mars

Etude ultrastructurale du Neuropore d\u27Amphioxus adulte (Branchiostoma lanceolatum Pallas)

Volume: 92Start Page: 845End Page: 84