34 research outputs found
Social media use and impact during the holiday travel planning process
Through an empirical study among holiday travellers, residing in the Former Soviet Union Republics, this paper presents a comprehensive view of role and impact of social media on the whole holiday travel planning process: Before, during and after the trip, providing insights on usage levels, scope of use, level of influence and trust. Findings suggest that social media are predominantly used after holidays for experience sharing. It is also shown that there is a strong correlation between perceived level of influence from social media and changes made in holiday plans prior to final decisions. Moreover, it is revealed that user-generated content is perceived as more trustworthy when compared to official tourism websites, travel agents and mass media advertising
Designing biomass lignins for the biorefinery
4 páginas.- 3 figuras. 17 referencias.- Comunicación oral presentada en el 16th European Workshop on Lignocellulosics and Pulp (EWLP) Gothenburg, Sweden, June 28 – July 1, 2022As ever more component monomers are discovered, lignin can no longer be regarded as deriving from just the three canonical monolignols. Pathway intermediates and additional products of truncated biosynthesis are now established lignin monomers. The array of acylated monolignols continues to expand. Game-changing findings have demonstrated that phenolics from alternative pathways, including flavonoids and hydroxystilbenes, are also involved in lignification, expanding the traditional concept. Beyond the basic science intrigue, these findings propound exciting new avenues for valorizing lignins, or for producing more readily extractable or depolymerizable lignins, in crop and bioenergy plants.We further acknowledge lots of colleagues and collaborators, and funding from the Swiss National Science Foundation (Synergia) grant # CRS115_180258, and the DOE Great Lakes Bioenergy Research Center (DOE BER Office of Science DE-SC0018409).N
Symphysiotony for mild cephalopelvic disproportion
SymphysiotomyThe operation of symphysiotomy was first performed by Claude-De La Corvee in 1655 on a recently dead patient (Munro Kerr and Chassar Moir 1956). Signault (quoted by Greig 1964) performed the first modern operation in 1777 on a patient who had a true conjugate of 6.5cms., and who had had 4 previous stillbirths. He obtained a live healthy baby but the mother unfortunately
suffered from a urinary fistula for the rest of her life. For the next hundred and fifty years the operation enjoyed several brief periods of popularity in Europe, but because it was performed on patients with gross pelvic contraction the inevitable urinary complications of damage to the bladder, urethra and vestibule followed.The incidence of haemorrhage and sepsis was also very
high, and the operation never gained general acceptance. In 1931 Zarate (1955) revived the operation with his technique of subcutaneous, partial or intracapsular symphysiotomy. Subsequently, Spain (1949) and Barry (1950, 1952) further popularized the operation in Ireland with their open technique. Barry (1950) declared that symphysiotomy offers a cure for disproportion, not a treatment.. Crichton and Seedat (1963) exhaustively evaluated the operation as a method of managing cases of mild cephalo-pelvic disproportion and reported on 1,200 cases with excellent results.Office of Global AIDS/US Department of Stat
Designer lignins: inspirations from Nature
Lignin remains one of the most significant barriers to the efficient utilization of lignocellulosic substrates, in processes ranging from ruminant digestibility to indus-trial pulping, and in the current focus on biofuels production. Inspired largely by the recalcitrance of lignin to biomass processing, plant engineering efforts have routinely sought to alter lignin quantity, composition, and structure by exploiting the inherent plasticity of lignin biosynthesis. More recently, researchers are attempting to strategically designplants for increased degradability by incorporating monomers that lead to a lower degree of polymerisation, reduced hydrophobicity, fewer bonds to other cell wall constituents, or novel chemically labile linkages in the polymer backbone.[1]In addition, the incorporation of value-added structures could help valorise lignin. Designer lignins may satisfy the biological requirement for lignification in plants while improving the overall efficiency of biomass utilisation.Researchers are now already beginning todesignlignins, by introducing novel phenolic precursors into the plant lignification process, to improve the ease with which the resulting lignins can be removed from the cell wall. Although possibilities abound, maintaining plant health is paramount and, ultimately, the plants themselves will dictate which of these approaches can be tolerated. Onesuch method, via the so-called ‘zip-lignin’ approach, is showing particular promise.[2-4]Poplar trees have been engineered to incorporate monolignol ferulate conjugates into the lignification process, resulting inthe introduction of readily cleavable ester linkages into the backbone of the polymer, and resulting in significantly improved processing. Various applications for which these altered trees seem well suited will be discussed. We’ll describe recent advances, including getting the monolignol ferulate conjugates into grasses, in which we were concerned that the natural p-coumaroylation of mono-lignols might compete. In addition, now that we have sensitive methods for determin-ing if/when/whether plants are making monolignol ferulate conjugates and using them for lignification (methods that have not previously been available), it appears that Nature herself may have already been exploring this avenue. We’ll provide insight into the plants that seem to be doingthis and try to elucidate how. [The question of why is likely to require a lot more time, research, and insight]. Finally, we’ll note other avenues, inspired by Nature, for lignin modification that have potential value for various processes.For example,the ramifications of finding that grasses are using aphenolic, tricin, a flavonoid from beyond the monolignol biosynthetic pathway to start lignin chainsare interesting indeed.[5,6]
[1] Y. Mottiar, R. Vanholme, W. Boerjan, J. Ralph, S. D. Mansfield, Curr. Opin. Biotechnol. 2016, 37, 190-200.
[2] J. H. Grabber, R. D. Hatfield, F. Lu, J. Ralph, Biomacromolecules 2008, 9, 2510-2516.
[3] J. Ralph, Phytochem. Rev. 2010, 9, 65-83.[4] C. G. Wilkerson, S. D. Mansfield, F. Lu, ...,D. Padmakshan, F. Unda, J. Rencoret, J. Ralph, Science 2014, 344, 90-93.
[5] J. C. del Río, J. Rencoret, P. Prinsen, Á. T. Martínez, J. Ralph, A. Gutiérrez, J. Agric. Food Chem. 2012, 60, 5922-5935.
[6] W. Lan,F. Lu, M. Regner, Y. Zhu, J. Rencoret, S. A. Ralph, U. I. Zakai, K. Morreel, W. Boerjan, J. Ralph, Plant Physiol. 2015, 167, 1284-1295Peer Reviewe