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971.
Inês P. Rosinha Grundtvig Søren Heintz Ulrich Krühne Krist V. Gernaey Patrick Adlercreutz John D. Hayler Andy S. Wells John M. Woodley 《Biotechnology advances》2018,36(7):1801-1814
The application of conventional organic solvents has been essential in several steps of bioprocesses in order to achieve sufficient economic efficiency. The use of organic solvents is frequently used either to partly or fully replace water in the reaction medium or as a process aid for downstream separation.Nowadays, manufacturers are increasingly requested to avoid and substitute solvents with hazardous potential. Therefore, the solvent selection must account for potential environmental hazards, health and safety problems, in addition to fulfilling the ideal characteristics for application in a process.For the first time, criteria including Environment, Health and Safety (EHS), as well as the technical requirements for reaction and separation have been reviewed, collected and integrated in a single organic solvent screening strategy to be used as a guideline for narrowing down the list of solvents to test experimentally. Additionally, we have also included a solvent selection guide based on the methodology developed in the Innovative Medicines Initiative CHEM21 (IMI CHEM21) project and applied specifically to water-immiscible solvents commonly used in bioprocesses. 相似文献
972.
Inês B. Gomes Ana Meireles Ana L. Gonçalves Darla M. Goeres Jelmer Sjollema Lúcia C. Simões 《Critical reviews in biotechnology》2018,38(5):657-670
Biofilms can cause severe problems to human health due to the high tolerance to antimicrobials; consequently, biofilm science and technology constitutes an important research field. Growing a relevant biofilm in the laboratory provides insights into the basic understanding of the biofilm life cycle including responses to antibiotic therapies. Therefore, the selection of an appropriate biofilm reactor is a critical decision, necessary to obtain reproducible and reliable in vitro results. A reactor should be chosen based upon the study goals and a balance between the pros and cons associated with its use and operational conditions that are as similar as possible to the clinical setting. However, standardization in biofilm studies is rare. This review will focus on the four reactors (Calgary biofilm device, Center for Disease Control biofilm reactor, drip flow biofilm reactor, and rotating disk reactor) approved by a standard setting organization (ASTM International) for biofilm experiments and how researchers have modified these standardized reactors and associated protocols to improve the study and understanding of medical biofilms. 相似文献
973.
974.
Karine Monceau Mariangela Arca Lisa Leprêtre Olivier Bonnard Gérard Arnold Denis Thiéry 《Journal of Insect Behavior》2018,31(1):1-11
Invasive species are now recognized as a major cause of native biodiversity loss worldwide. In the current deleterious context for pollinators, the invasive yellow-legged hornet, Vespa velutina, represents an additional threat to the domestic honeybee, Apis mellifera, in Europe. Therefore, understanding the impact of this predator on honeybee colonies is of major importance. In the present study, we tried to assess the impact of V. velutina on the honeybee foraging and defence behaviour based on the video monitoring of two hives. Balling behaviour is reported here for the first time under natural conditions in A. mellifera against V. velutina in Europe. Although these results are preliminary and should be carefully considered, we found that the number of hornets impacted honeybee foraging and defence behaviours. More defensive behaviours were notified in the hive, which survives slightly longer. This may suggest that selecting for more defensive colonies may provide an interesting perspective. 相似文献
975.
Audrey Robillard Gilles Gauthier Jean‐François Therrien Joël Bêty 《Journal of avian biology》2018,49(5)
Migratory species can exploit many habitats over vast geographic areas and adopt various patterns of space and habitat use throughout their annual cycle. In nomadic species, determinants of habitat use during the non‐breeding season are poorly known due to the unpredictability of their movement patterns. Here, we analysed variability in wintering space and habitat use by a highly nomadic species, the snowy owl, in eastern North America. Using 21 females tracked by satellite telemetry between 2007 and 2016, we 1) assessed how space use patterns in winter varied according to the type of environment (marine vs terrestrial), latitudinal zone (Arctic vs temperate), local snow conditions and lemming densities and 2) investigated winter habitat and site fidelity. Our results confirmed a high inter‐individual variation in patterns of habitat use by wintering snowy owls. Highly‐used areas were concentrated in the Arctic and in the marine and coastal environments. Owls wintering in the marine environment travelled over longer distances during the winter, had larger home ranges and these were divided in more smaller zones than individuals in terrestrial environments. Wintering home range sizes decreased with high winter lemming densities, use of the marine environment increased following high summer lemming densities, and a thick snow cover in autumn led to later settlement on the wintering ground. Contrary to expectations, snowy owls tended to make greater use of the marine environment when snow cover was thin. Snowy owls were highly consistent in their use of a given wintering environment and a specific latitudinal zone between years, but demonstrated flexibility in their space use and a modest site fidelity. The snowy owls’ consistency in wintering habitat use may provide them with advantages in terms of experience but their mobility and flexibility may help them to cope with changing environmental conditions at fine spatial scale. 相似文献
976.
977.
Caroline Vianna Velasco Castilho Jaime Fidalgo Ferra Neto Suzana Guimarães Leitão Carolina Santos Barreto Shaft Corrêa Pinto Nina Claudia Barboza da Silva 《Plant Cell, Tissue and Organ Culture》2018,133(3):311-323
Anemia tomentosa var. anthriscifolia is an aromatic fern with a pleasant woody aroma and antimycobacterial activity. In this paper, we describe for the first time its spore-derived gametophyte development and the effect of indole-3-acetic acid and jasmonic acid on in vitro gametophyte/sporophyte development, as well as volatile compound production. Volatiles were obtained by simultaneous distillation and extraction (SDE) and analyzed by high resolution gas chromatography coupled with mass spectrometry. Spore-derived gametophytes were able to develop into sporophytes independently of the media culture composition, even when no plant growth regulator was added. Fifty different substances were detected in all in vitro A. tomentosa SDE extracts, while 20 were detected in the wild SDE plant extract. Monoterpenes were more prevalent (69.8–89.8%) than sesquiterpenes (9.4–28.7%) in in vitro plants, while sesquiterpenes represent 97.5% of the volatiles produced by the wild-grown plants. The major monoterpene components in in vitro plants were α-pinene (9.3–24.3%), trans-pinocarveol (20.6–27.9%), pinocarvone (15.4–25.1%) and myrtenyl acetate (6.4–12.3%). The triquinane sesquiterpenes silphiperfol-6-ene (0.6–2.9%), α-guaiene (0.5–2.5%), β-barbatene (1.1–3.9%) and 9-epi-presilphiperfolan-1-ol (2.5–5.6%) represent the most abundant sesquiterpenes. The changes in the monoterpene/sesquiterpene rates between micropropagated and wild plants are not related to the presence of JA or IAA in the media culture. Further studies are still needed to obtain a complete understanding of the factors leading to these results, which could be related to differences in the irradiance levels of in vitro plants versus those from a wild environment, as well as the developmental stage of the plants. This is the first report of the use of plant growth regulators on Anemia tomentosa in vitro culture development and their effects on volatile profiles. 相似文献
978.
Karim C. Piacentini L. O. Rocha G. D. Savi L. Carnielli-Queiroz F. G. Almeida E. Minella B. Corrêa 《Mycotoxin Research》2018,34(3):173-178
Barley (Hordeum vulgare L.) is an important cereal crop for food and represents one of the main ingredients in beer production. Considering the importance of barley and its derived products, the knowledge about the mycotoxin contamination in the barley production is essential in order to assess its safety. In this study, the levels of deoxynivalenol (DON) and zearalenone (ZEN) in brewing barley were determined using a LC-MS/MS method. A survey was conducted in 2015 to estimate the mycotoxin levels in these products (n?=?76) from four crop regions in Brazil. The results showed high levels of DON and ZEN in the analyzed samples, with contamination levels of 94 and 73.6%, respectively. The mean levels of DON and ZEN ranged from 1700 to 7500 μg/kg and from 300 to 630 μg/kg, respectively. Barley samples from regions 1 and 2 presented higher levels of ZEN and DON, respectively, and those from region 4 presented lower levels of both. Co-occurrence of DON and ZEN was seen in the majority of the barley grain samples, and the mycotoxin content was above the maximum levels established by the Brazilian and European regulations. 相似文献
979.
Lennart F. Johansson Hendrik A. de Weerd Eddy N. de Boer Freerk van Dijk Gerard J. te Meerman Rolf H. Sijmons Birgit Sikkema-Raddatz Morris A. Swertz 《BMC bioinformatics》2018,19(1):531
Background
Various algorithms have been developed to predict fetal trisomies using cell-free DNA in non-invasive prenatal testing (NIPT). As basis for prediction, a control group of non-trisomy samples is needed. Prediction accuracy is dependent on the characteristics of this group and can be improved by reducing variability between samples and by ensuring the control group is representative for the sample analyzed.Results
NIPTeR is an open-source R Package that enables fast NIPT analysis and simple but flexible workflow creation, including variation reduction, trisomy prediction algorithms and quality control. This broad range of functions allows users to account for variability in NIPT data, calculate control group statistics and predict the presence of trisomies.Conclusion
NIPTeR supports laboratories processing next-generation sequencing data for NIPT in assessing data quality and determining whether a fetal trisomy is present. NIPTeR is available under the GNU LGPL v3 license and can be freely downloaded from https://github.com/molgenis/NIPTeR or CRAN.980.
Ricardo Cyrne Inês C. Rosa Filipa Faleiro Gisela Dionísio Miguel Baptista Ana Couto Marta Pola Rui Rosa 《Helgoland Marine Research》2018,72(1):14
The sudden appearance and disappearance of nudibranchs in intertidal areas have puzzled researchers all over the world, giving rise to a great diversity of theories to explain it. Here we conducted a five-year survey to evaluate seasonal changes in the abundance of Dendrodoris herytra and D. grandiflora in the Sado estuary (Portugal) and to explore a possible relationship with environmental factors such as temperature, salinity, turbidity and dissolved oxygen. Moreover, we report, for the first time, the capacity of Dendrodoris nudibranchs to tolerate emersion (unhidden and completely exposed to sun exposure) during low tides. Our results showed that both species consistently started to appear emerged in March, reaching a peak abundance between April and May, and completely disappearing in July. In both species, this temporal trend was significantly associated with water temperature, turbidity, and dissolved oxygen, but not with salinity. We argue that the sudden appearance and disappearance of these nudibranchs in intertidal areas may result from a seasonal horizontal movement of adult nudibranchs from subtidal areas to mate in intertidal areas during spring, when phytoplankton production is enhanced and planktotrophic larvae may benefit from greater food availability. 相似文献