Chromophores from hexeneuronic acids: identification of HexA-derived chromophores

© 2017, The Author(s). Hexeneuronic acids (HexA) have long been known as triggers for discoloration processes in glucuronoxylan-containing cellulosic pulps. They are formed under the conditions of pulping from 4-O-methylglucuronic acid residues, and are removed in an “A stage” along the bleaching sequences, which mainly comprises acidic washing treatments. The chemical structures of HexA-derived chromophoric compounds 4–8, which make up 90% of the HexA-derived chromophores, are reported here for the first time. The compounds are ladder-type, mixed quinoid-aromatic oligomers of the bis(furano)-[1,4]benzoquinone and bis(benzofurano)-[1,4] benzoquinone type. The same chromophoric compounds are generated independently of the starting material, which can be either a) HexA in pulp, b) the HexA model compound methyl 1- 13 C-4-deoxy-β-L-threo-hex-4-enopyranosiduronic acid (1) or c) a mixture of the primary degradation intermediates of 1, namely 5-formyl-furancarboxylic acid (2) and 2-furancarboxylic acid (3). Isotopic labeling ( 13 C) in combination with NMR spectroscopy and mass spectrometry served for structure elucidation, and final confirmation was provided by X-ray structure analysis. 13 C-Isotopic labeling was also used to establish the formation mechanisms, showing all the compounds to be composed of condensed, but otherwise largely intact, 2-carbonylfuran and 2-carbonylfuran-5-carboxylic acid moieties. These results disprove the frequent assumption that HexA-derived or furfural-derived chromophores are linear furanoid polymers, and might have a direct bearing on structure elucidation studies of “humins”, which are formed as dark-colored byproducts in depolymerization of pentosans and hexosans in different biorefinery scenarios

Allen, McCright, and Dietz Data

This is survey data from a convenience sample across the US for testing a newly created instrument to measure identification with different social movements

Values in environmental research: Citizens’ views of scientists who acknowledge values

<div><p>Scientists who perform environmental research on policy-relevant topics face challenges when communicating about how values may have influenced their research. This study examines how citizens view scientists who publicly acknowledge values. Specifically, we investigate whether it matters: if citizens share or oppose a scientist’s values, if a scientist’s conclusions seem contrary to or consistent with the scientist’s values, and if a scientist is assessing the state of the science or making a policy recommendation. We conducted two 3x2 factorial design online experiments. Experiment 1 featured a hypothetical scientist assessing the state of the science on the public-health effects of exposure to Bisphenol A (BPA), and Experiment 2 featured a scientist making a policy recommendation on use of BPA. We manipulated whether or not the scientist expressed values and whether the scientist’s conclusion appeared contrary to or consistent with the scientist’s values, and we accounted for whether or not subjects’ values aligned with the scientist’s values. We analyzed our data with ordinary least squares (OLS) regression techniques. Our results provide at least preliminary evidence that acknowledging values may reduce the perceived credibility of scientists within the general public, but this effect differs depending on whether scientists and citizens share values, whether scientists draw conclusions that run contrary to their values, and whether scientists make policy recommendations.</p></div

Effects of scientists’ policy recommendations and expressed values on respondents’ trust in them.

<p>Effects are relative to a scientist not expressing a preference for particular values and are net of control variables; see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0186049#pone.0186049.t001" target="_blank">Table 1</a>. Green arrows are used when the scientist’s recommendation coincides with the scientist’s values; red arrows are used when the scientist’s recommendation conflicts with the scientist’s values.</p

Measures of the effect of scientists’ policy recommendations and expressed values on respondents’ trust (Experiment 2).

<p>Measures of the effect of scientists’ policy recommendations and expressed values on respondents’ trust (Experiment 2).</p

Measures of the effect of scientists’ conclusions and expressed values on respondents’ positive attitude toward them (Experiment 1).

<p>Measures of the effect of scientists’ conclusions and expressed values on respondents’ positive attitude toward them (Experiment 1).</p

Effects of scientists’ policy recommendations and expressed values on respondents’ positive affect toward them.

<p>Effects are relative to a scientist not expressing a preference for particular values and are net of control variables; see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0186049#pone.0186049.t001" target="_blank">Table 1</a>. Green arrows are used when the scientist’s recommendation coincides with the scientist’s values; red arrows are used when the scientist’s recommendation conflicts with the scientist’s values.</p

Measures of the effect of scientists’ policy recommendations and expressed values on respondents’ positive attitude toward them (Experiment 2).

<p>Measures of the effect of scientists’ policy recommendations and expressed values on respondents’ positive attitude toward them (Experiment 2).</p

Going Beyond the Millennium Ecosystem Assessment: An Index System of Human Dependence on Ecosystem Services

<div><p>The Millennium Ecosystem Assessment (MA) estimated that two thirds of ecosystem services on the earth have degraded or are in decline due to the unprecedented scale of human activities during recent decades. These changes will have tremendous consequences for human well-being, and offer both risks and opportunities for a wide range of stakeholders. Yet these risks and opportunities have not been well managed due in part to the lack of quantitative understanding of human dependence on ecosystem services. Here, we propose an index of dependence on ecosystem services (IDES) system to quantify human dependence on ecosystem services. We demonstrate the construction of the IDES system using household survey data. We show that the overall index and sub-indices can reflect the general pattern of households' dependences on ecosystem services, and their variations across time, space, and different forms of capital (i.e., natural, human, financial, manufactured, and social capitals). We support the proposition that the poor are more dependent on ecosystem services and further generalize this proposition by arguing that those disadvantaged groups who possess low levels of any form of capital except for natural capital are more dependent on ecosystem services than those with greater control of capital. The higher value of the overall IDES or sub-index represents the higher dependence on the corresponding ecosystem services, and thus the higher vulnerability to the degradation or decline of corresponding ecosystem services. The IDES system improves our understanding of human dependence on ecosystem services. It also provides insights into strategies for alleviating poverty, for targeting priority groups of conservation programs, and for managing risks and opportunities due to changes of ecosystem services at multiple scales.</p></div