Zinc Oxide-Modified Mordenite as an Effective Catalyst for the Dehydrogenation of (bio)Ethanol to Acetaldehyde

The direct transformation of ethanol to acetaldehyde is an important step in the cascade conversion of bioethanol to higher value chemicals and for the development of sustainable fuels. Herein, zinc oxide supported on alkali cation-exchanged mordenite (ZnO/M–MOR) prepared by a simple wetness impregnation method, is shown to be a selective and stable catalyst for the direct dehydrogenation of ethanol to acetaldehyde at 400 °C under continuous flow conditions. Through variation of the ZnO loading and the zeolite counter-cation (Na, K, Rb, Cs), an optimum catalyst material was identified, ZnO/Rb–MOR loaded at 3.5 wt% Zn. Acetaldehyde productivity (normalised to Zn) could be increased by over 80% and ethylene selectivity reduced to 0.9 % through simple variation of the extra-framework alkali cation. Very low ethylene production leads to low levels of carbonaceous deposits and therefore minimal deactivation at short time on stream (< 5 h). Detailed analysis of the optimized system reveals excellent selectivity and stability beyond 120 h time on stream, resulting in an average acetaldehyde productivity of 16 mmol gcat−1 h−1 and overall acetaldehyde selectivity of 90% whilst operating at an ethanol conversion level of 40 %. Additionally, the use of a zeolite support is shown to greatly improving the usage efficiency of Zn atoms by virtue of an acetaldehyde productivity increase from 20 to 48 mmol mmolZn−1 h−1 for unsupported and supported ZnO, respectively. The new catalyst system shows that ZnO can be tuned to give very low ethylene selectivity and extended lifetimes in ethanol dehydrogenation to acetaldehyde which has not previously been reported

The Drosophila genome nexus: a population genomic resource of 623 Drosophila melanogaster genomes, including 197 from a single ancestral range population.

Hundreds of wild-derived Drosophila melanogaster genomes have been published, but rigorous comparisons across data sets are precluded by differences in alignment methodology. The most common approach to reference-based genome assembly is a single round of alignment followed by quality filtering and variant detection. We evaluated variations and extensions of this approach and settled on an assembly strategy that utilizes two alignment programs and incorporates both substitutions and short indels to construct an updated reference for a second round of mapping prior to final variant detection. Utilizing this approach, we reassembled published D. melanogaster population genomic data sets and added unpublished genomes from several sub-Saharan populations. Most notably, we present aligned data from phase 3 of the Drosophila Population Genomics Project (DPGP3), which provides 197 genomes from a single ancestral range population of D. melanogaster (from Zambia). The large sample size, high genetic diversity, and potentially simpler demographic history of the DPGP3 sample will make this a highly valuable resource for fundamental population genetic research. The complete set of assemblies described here, termed the Drosophila Genome Nexus, presently comprises 623 consistently aligned genomes and is publicly available in multiple formats with supporting documentation and bioinformatic tools. This resource will greatly facilitate population genomic analysis in this model species by reducing the methodological differences between data sets

Greene, crítico

Taylor, R.; Ced, J.; Nuño, A. (1999). Greene, crítico. La madriguera. (23):58-59. http://hdl.handle.net/10251/41816.Importación Masiva58592

An ecological analysis of factors associated with food insecurity in South Australia, 2002-7

In order to estimate the extent of food insecurity in South Australia and its relationship with a variety of socio-economic variables, Design Data collected routinely from 2002 to 2007 by SA Health were analysed. An ecological analysis of data collected by the South Australian Monitoring and Surveillance System (SAMSS) that collects data on key health indicators. Questions on food security are asked periodically from July 2002 to December 2007. Seven per cent (1342/19 037) of subjects reported running out of food during the previous year and not having enough money to buy food (food insecurity). Logistic regression analysis found food insecurity to be highest in households with low levels of education, limited capacity to save money, Aboriginal households, and households with three or more children. Conclusions The study confirms that food insecurity is strongly linked to economic disadvantage. Increasing cost of food is likely to exacerbate food insecurity. This is of concern given that food insecurity is associated with poor health, especially obesity and chronic disease. Comprehensive action at all levels is required to address root causes of food insecurity. Regular surveillance is required to continue to monitor levels of food security, but more in-depth understandings, via qualitative research, would be useful

'Health is the number one thing we go for': healthism, citizenship and food choice

This paper explores the centrality of pursuit of health to discourse around food purchasing and eating behaviours. Forty-seven participants from metropolitan and rural South Australia were interviewed about how they decided what to purchase and to eat. The majority (n=39) cite the desire to eat healthily as a consideration in food purchasing. Participants reflect upon a personal and moral responsibility to eat well and to feed their family healthily, a duty that is supported by models of governance which favour personal responsibility for health. While all participants reflect upon this responsibility, it is rejected by a group of males on limited incomes who choose food on the basis of cost, taste, convenience and lack of trust in the health care system. The existence of a moral discourse around food is viewed as an example of healthism in which health is central to all aspects of life and self discipline a means to achieving health

Comparative examination of trust during times of a food scandal in Europe and Australia

This study compared public confidence in truth-telling by food chain actors in selected EU countries where there have been a number of food safety problems, with consumers in Australia where there have been fewer food crises. A computer-assisted telephone interviewing survey was used to address aspects of truth-telling at times of a food scandal with a random sample of 1109 participants across all Australian states (response rate 41.2%). Results were compared with a survey in six EU countries which had asked similar questions. Australians' trust in truth-telling by food chain actors was low, with 14.2% of the sample expecting various institutions and individuals to tell the whole truth during times of a food scandal. When compared with EU countries, Australia occupied a middle position in trust distribution, and was more similar to Great Britain in giving farmers the most trust in truth-telling. This study has demonstrated that in Australia, as in many EU countries, trust in truth-telling at a time of food scandal is low. The credibility of the food system is highly vulnerable under times of food crisis and once trust in broken, it is difficult to restore

Demographic indicators of trust in federal, state and local government: implications for Australian policy makers

Age, household size, household income, IRSD and ARIA were found to be significant indicators for trust in federal, state and local government. Trust in state government is lower for older respondents and respondents living in inner and outer regional areas. Trust in local council is lower in respondents living in inner regional areas, respondents living in disadvantaged areas, and respondents in the income bracket of $60 001 to$100 000. Trust in federal government is lower for older respondents and respondents living in disadvantaged areas. Of note is diminished trust in government among older, regional and lower income ($30 001–$60 000) respondents

The importance of food issues in society: Results from a national survey in Australia

This item is under embargo for a period of 12 months from the date of publication, in accordance with the publisher's policy.Aim: It has been demonstrated previously that consumer attitudes about food issues influence and shape consumer behaviour. The aim of this paper was to identify demographic and socio-economic variables associated with a range of consumer opinions regarding the importance of four pre-selected food issues. Methods: A National survey conducted in Australia (random sample n=1109; response rate 41.2%) was undertaken in 2009 to investigate consumer opinions regarding food issues that may influence food choice and behaviour. Respondents were specifically asked whether the following were important food issues in society; additives, genetically modified (GM) foods, unhealthy eating, and food allergies. Results: Most respondents considered unhealthy eating (96.1%) and food allergies (92.1%) to be important issues in society. Fewer participants, but still the majority, regarded additives (78.5%) and GM foods (67.7%) as important. The study identified that specific food issues were of particular concern to women, older respondents, respondents with an income between $30,000 and$60,000 (AUD), and respondents living in a household of five or more people. Concerns about GM foods and additives were associated with the greatest number of demographic and socio-economic variables studied. Conclusion: This paper has confirmed that the food issues studied were important to the participants surveyed. Demographic and socioeconomic factors were predictive of consumer opinion on the importance of individual food issues and may be useful to inform strategies and campaigns to address consumer concerns and public worries about food

RETENTION OF LARVAL ROCKFISHES, SEBASTES, NEAR NATAL HABITAT IN THE SOUTHERN CALIFORNIA BIGHT, AS INDICATED BY MOLECULAR IDENTIFICATION METHODS

ABSTRACT Larval (&lt;16 mm SL) Sebastes spp. that could not be identified visually were identified with molecular genetic methods from plankton samples collected during a California Cooperative Oceanic Fisheries Investigations (CalCOFI) cruise in April 1999. Our goals were to characterize natal habitat and to determine the abundances of individual rockfish species in CalCOFI ichthyoplankton samples. This is the first time the entire complex of Sebastes larvae collected during a CalCOFI cruise has been identified to species. For three abundant species, we found a significant association between abundance and stations within the Southern California Eddy (SCE), and a significant relationship between the distribution of 1-d-old larvae and potential adult habitat for the most narrowly distributed of the three species. These results suggest that the interplay of natal spawning habitat overlaid by the persistent SCE contributes to larval retention in this region. We also found low abundance and number of occurrences for larvae of the nearshore subgenus Pteropodus, suggesting that CalCOFI stations are too far offshore to evaluate distributions of this group