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991.
Comparative Effects of Cholesterol and β‐Sitosterol on the Liposome Membrane Characteristics 下载免费PDF全文
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The local authorities demonstrate their willingness to implement sound local sustainable energy policies, especially through their participation in the Covenant of Mayors (CoM). However, in rural environments, namely areas outside of large cities and towns, fulfilling their CoM commitments, especially as regards the local energy planning at the medium- to long-term scale, can come with very different and sometimes challenging constraints. In this context, the main objective of this paper is the assessment of the local communities’ needs and priorities, so as to identify the key parameters that should be taken into consideration during the development of their Sustainable Energy Action Plan. The adopted approach was implemented in rural communities from four countries (Austria, Croatia, Greece and Portugal). From the results obtained, the need for a methodology, appropriately customised to the rural communities’ characteristics, was determined, addressing especially interested stakeholders who are not ‘experts’ in the field. 相似文献
994.
McDougall Alexandra Abedi Zahra Ivey Douglas G. 《Journal of Applied Electrochemistry》2022,52(3):437-459
Journal of Applied Electrochemistry - Electrochemical catalysts for the air electrode of Zn-air rechargeable batteries were fabricated from nitrogen-doped carbon nanotubes (N-CNTs), combined with... 相似文献
995.
Banu Alexandra Preda Loredana Marcu Maria Dinca Luciana Laura Maxim Monica Elisabeta Dobri Gabriel 《Metallurgical and Materials Transactions A》2022,53(6):2060-2070
Metallurgical and Materials Transactions A - The corrosion behavior of selective laser melted Ti–6Al–4V alloy (SLM Ti–6Al–4V) was assessed in 0.1 M lactic acid + 0.1 M NaCl... 相似文献
996.
Inês Serrenho Miguel Rosado Alexandra Dinis Carla M. Cardoso Mrio Gros Bruno Manadas Graa Baltazar 《International journal of molecular sciences》2021,22(6)
Neonatal hypoxic-ischemic encephalopathy (HIE) is an important cause of mortality and morbidity in the perinatal period. This condition results from a period of ischemia and hypoxia to the brain of neonates, leading to several disorders that profoundly affect the daily life of patients and their families. Currently, therapeutic hypothermia (TH) is the standard of care in developing countries; however, TH is not always effective, especially in severe cases of HIE. Addressing this concern, several preclinical studies assessed the potential of stem cell therapy (SCT) for HIE. With this systematic review, we gathered information included in 58 preclinical studies from the last decade, focusing on the ones using stem cells isolated from the umbilical cord blood, umbilical cord tissue, placenta, and bone marrow. Outstandingly, about 80% of these studies reported a significant improvement of cognitive and/or sensorimotor function, as well as decreased brain damage. These results show the potential of SCT for HIE and the possibility of this therapy, in combination with TH, becoming the next therapeutic approach for HIE. Nonetheless, few preclinical studies assessed the combination of TH and SCT for HIE, and the existent studies show some contradictory results, revealing the need to further explore this line of research. 相似文献
997.
Ruben-Simon Kühnel Shahmahmood Obeidi Mechthild Lübke Alexandra Lex-Balducci Andrea Balducci 《Journal of Applied Electrochemistry》2013,43(7):697-704
The wetting time of porous electrodes with electrolytes based on organic solvents and ionic liquids, respectively, was investigated with two different techniques: with a tensiometer and by impedance spectroscopy. The results of this study showed that the wetting time of a porous electrode with ionic liquid-based electrolytes is up to 20 times longer than that with electrolytes comprising organic solvents. A significant reduction in the wetting time with ionic liquid-based electrolytes could be achieved by adding organic solvents. This effect can be explained by the interplay of reduced viscosity, increased surface tension and change in contact angle caused by the addition of the organic solvent, with the lower viscosity being the main driver of improved wetting kinetics. 相似文献
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999.
Richard Noss Alexandra Poulovassilis Eirini Geraniou Sergio Gutierrez-Santos Celia Hoyles Ken Kahn George D. Magoulas Manolis Mavrikis 《Computers & Education》2012
This paper charts the design and application of a system to support 11–14 year old students’ learning of algebraic generalisation, presenting students with the means to develop their understanding of the meaning of generality, see its power for mathematics and develop algebraic ways of thinking. We focus squarely on design, while taking account of both technical and pedagogical issues and challenges, and provide an account of how we have designed and built a system with a very close fit to our knowledge of students’ difficulties with the subject matter. We report the challenges involved in building a system that is both intelligent and exploratory, a learning environment in which both student and teacher are supported without explicit tutoring. 相似文献
1000.
Alice de Boyer des Roches Marion Faure Alexandra Lussert Vincent Herry Pascal Rainard Denys Durand Gilles Foucras 《Journal of dairy science》2017,100(10):8385-8397
Bovine mastitis is one of the most common diseases in the dairy industry and it is a major welfare problem. Pain during mastitis is generally assessed through behavior but a combination of indicators would increase the chances of detecting pain and assessing its intensity. The aim of this study was to assess behavioral and patho-physiological responses as possible signs of pain experienced by cows after experimental intramammary challenge (mastitis) with Escherichia coli. Six Holstein-Friesian cows received an inoculation of E. coli P4 in one healthy quarter. Evolution of the disease was assessed using bacteriological growth and somatic cell counts (SCC). Cows' response to the challenge was monitored by direct behavioral and clinical observations, data loggers, rumen temperature sensors, and indicators of inflammation, stress, and oxidative status. From all data recorded, the variables that contributed most to the discrimination of mastitis phases were obtained by factorial discriminant analysis. Baseline levels of all indicators corresponded to values before challenge. Specifically, we weighted data relating to lying behavior by the observations at the same hour of the day before challenge to eliminate the circadian rhythm effect. We identified 3 phases that were discriminated by factorial discriminant analysis with good performance. Nine indicators varied according to the phase of the disease: cows' attitude toward their surroundings, tail position, clinical signs, ear position, variation of postural changes, concentrations of haptoglobin and serum amyloid A (SAA), cortisol blood levels, and rumen temperature (as a surrogate for body temperature). In phase 1 (4 to 8 h postinoculation), E. coli proliferated exponentially in milk but inflammation indicators remained at baseline levels. Cows were less attentive toward their surroundings (median score, 0.63), and postural changes (lying/standing) were less frequent (0.75 times from baseline). In phase 2 (12 to 24 h postinoculation), bacterial concentrations peaked around 12 h and then began to decrease concomitantly with a sharp SCC increase. Cows were less attentive toward their surroundings (score, 0.54), had high plasma cortisol (31.3 ng/mL) and SAA (100.3 µg/mL) concentrations, and rumen temperature was increased (40.3°C). In phase 3 (32 to 80 h postinoculation), bacterial concentrations decreased concomitantly with high SCC levels. Cows had high levels of haptoglobin (0.57 mg/mL) and SAA (269 µg/mL) but showed no behavioral changes. Dairy cows displayed changes of behavioral, inflammatory, and stress parameters after E. coli mammary inoculation. Our results suggest that cows may have experienced discomfort in the preclinical phase (phase 1) and pain in the acute phase (phase 2) but neither discomfort nor pain in the remission phase (phase 3). Although larger controlled studies are needed to confirm our findings, this knowledge could be useful for early detection of E. coli mastitis and for decision-making regarding the initiation of pain-relief treatment during mastitis in dairy cows. This would improve animal welfare and potentially faster disease remission. 相似文献