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351.
Pianaro A Flach A Patricio EF Nogueira-Neto P Marsaioli AJ 《Journal of chemical ecology》2007,33(5):971-984
Wax constituents produced by worker bees and the chemistry of the nest batumen (mixture of wax, mud, and floral materials)
in a Melipona scutellaris colony changed when it was invaded by Melipona rufiventris workers. Gas chromatography/mass spectrometry analyses showed that after invasion, the M. scutellaris workers of the invaded colony produced waxes with higher relative abundance of triacontanyl acetate and decreased the amounts
of n-alkanes and n-9-alkenes. On the other hand, waxes from M. rufiventris workers displayed few changes. The change in the composition of the M. scutellaris waxes chemically differentiates that species from the M. rufiventris invader workers. Comparative analyses of batumens samples from pure and invaded colonies revealed greater amounts of terpenes
and phenolic derivatives in the batumen from the invaded colony. This is the first report on the chemical characterization
of batumens from stingless bees. 相似文献
352.
Energy balances are usually aggregated at the level of subsector and energy carrier. While heating and cooling accounts for half the energy demand of the European Union’s 28 member states plus Norway, Switzerland and Iceland (EU28 + 3), currently, there are no end-use balances that match Eurostat’s energy balance for the industrial sector. Here, we present a methodology to disaggregate Eurostat’s energy balance for the industrial sector. Doing so, we add the dimensions of temperature level and end-use. The results show that, although a similar distribution of energy use by temperature level can be observed, there are considerable differences among individual countries. These differences are mainly caused by the countries’ heterogeneous economic structures, highlighting that approaches on a process level yield more differentiated results than those based on subsectors only. We calculate the final heating demand of the EU28 + 3 for industrial processes in 2012 to be 1035, 706 and 228 TWh at the respective temperature levels > 500 °C (e.g. iron and steel production), 100–500 °C (e.g. steam use in chemical industry) and < 100 °C (e.g. food industry); 346 TWh is needed for space heating. In addition, 86 TWh is calculated for the industrial process cooling demand for electricity in EU28 + 3. We estimate additional 12 TWh of electricity demand for industrial space cooling. The results presented here have contributed to policy discussions in the EU (European Commision 2016), and we expect the additional level of detail to be relevant when designing policies regarding fuel dependency, fuel switching and specific technologies (e.g. low-temperature heat applications). 相似文献
353.
Statistical analysis of wheat under different seed treatments: development of a discriminative model based on physicochemical and rheological properties
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354.
Pinto Patricio X. Al-Abed Souhail R. Holder Christopher D. Warner Richard McKernan John Fulton Stephanie Somerville Eric 《Mine Water and the Environment》2018,37(1):31-41
Mine Water and the Environment - The exposure of readily soluble components of overburden materials from surface coal mining to air and water results in mineral oxidation and carbonate mineral... 相似文献
355.
Supplementation with Docosahexaenoic Acid and Extra Virgin Olive Oil Prevents Liver Steatosis Induced by a High‐Fat Diet in Mice through PPAR‐α and Nrf2 Upregulation with Concomitant SREBP‐1c and NF‐kB Downregulation
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356.
Xinyun Li Marc Toro Fei Lu Jung On Alla Bailey Thomas Debies 《Journal of Adhesion Science and Technology》2016,30(20):2212-2223
Polystyrene (PS) was treated with vacuum UV (VUV) (λ = 104.8 and 106.7 nm) photo-oxidation and X-ray photoelectron spectroscopy detected a controlled increase in the atomic percentage of oxygen up to a saturation level of ca. 20 at% O. Initially, C–O and carbonyl groups are observed due to the formation of alcohols, ethers, esters, and ketones. Water contact angle measurements showed ca. 25% increase in hydrophilicity of the surface with oxidation. Atomic Force Microscopy observed little changes in surface roughness with treatment time. The super water absorbent polymer poly(acrylic acid) was thinly grafted to the modified PS surface. 相似文献
357.
Luis Toro Alberto Cavazos Rafael Colás 《Journal of Materials Engineering and Performance》2009,18(9):1183-1192
A fuzzy logic inference system was designed to predict the grain size of Inconel 718 alloy after upset forging. The system
takes as input the original grain size, temperature, and reduction rate at forging and predicts the final grain size at room
temperature. It is assumed that the system takes into account the effects that the heterogeneity of deformation and grain
growth exerts in this particular material. Experimental trials were conducted in a factory that relies on upset forging to
produce preforms for ring rolling. The grain size was reported as ASTM number, as this value is used on site. A first attempt
was carried out using a series of 15 empirically based set of rules; the estimation error with these was above two ASTM numbers;
which is considered to be very high. The system was modified and expanded to take into account 28 rules; the estimation error
of this new system resulted to be close to one ASTM number, which is considered to be adequate for the prediction. 相似文献
358.
Miguel A. Patricio Jesús García Antonio Berlanga José M. Molina 《International journal of imaging systems and technology》2009,19(3):208-220
In this article, an efficient and novel approach for video data association is developed. This new method is formulated as a search across the hypotheses space defined by the possible association among tracks and detections, carried out for each frame of a video sequence. The full data association problem in visual tracking is formulated as a combinatorial hypotheses search with a heuristic evaluation function taking into account structural and specific information such as distance, shape, color, etc. To guarantee real‐time performance, a time limit is set for the search process explore alternative solutions. This time limit defines the upper bound of the number of evaluations depending on search algorithm efficiency. Estimation distribution algorithms are proposed as an efficient evolutionary computation technique to search in this hypothesis space. Finally, an exhaustive comparison of the performance of alternative algorithms is carried out considering complex representative situations in real video sets. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 208–220, 2009 相似文献
359.
Essential fatty acids in visual and brain development 总被引:22,自引:5,他引:17
Ricardo Uauy Dennis R. Hoffman Patricio Peirano David G. Birch Eileen E. Birch 《Lipids》2001,36(9):885-895
360.
María Jos de Castro Mireia del Toro Roberto Giugliani María Luz Couce 《International journal of molecular sciences》2021,22(17)
The need for long-lasting and transformative therapies for mucopolysaccharidoses (MPS) cannot be understated. Currently, many forms of MPS lack a specific treatment and in other cases available therapies, such as enzyme replacement therapy (ERT), do not reach important areas such as the central nervous system (CNS). The advent of newborn screening procedures represents a major step forward in early identification and treatment of individuals with MPS. However, the treatment of brain disease in neuronopathic MPS has been a major challenge to date, mainly because the blood brain barrier (BBB) prevents penetration of the brain by large molecules, including enzymes. Over the last years several novel experimental therapies for neuronopathic MPS have been investigated. Gene therapy and gene editing constitute potentially curative treatments. However, despite recent progress in the field, several considerations should be taken into account. This review focuses on the state of the art of in vivo and ex vivo gene therapy-based approaches targeting the CNS in neuronopathic MPS, discusses clinical trials conducted to date, and provides a vision for the future implications of these therapies for the medical community. Recent advances in the field, as well as limitations relating to efficacy, potential toxicity, and immunogenicity, are also discussed. 相似文献