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991.
The Scottish Executive has set ambitious targets of achieving 100% of electricity from renewable sources by 2020. As Scotland has the best offshore wind resources in Europe, the development of this energy source is crucial for reaching these targets. However, the development of offshore wind raises a number of issues related to economic viability, grid connection and public acceptability. This paper investigates these areas in greater depth, using a case study of the Firth of Forth offshore wind farm, in order to determine if these barriers can be overcome in time to make a valuable contribution to 2020 targets. Through interviews with relevant stakeholders, it emerged that there are various obstacles which are impeding progress in offshore wind development in Scotland. It became evident that stakeholder opposition, an inadequate renewable energy support mechanism, and the insufficient grid infrastructure off the Scottish coast are posing barriers, and hindering development. It became apparent that in order to overcome these barriers, a number of changes need to take place. A more inclusive approach to stakeholder engagement is required, which facilitates the sharing of knowledge. In order to improve the economic viability of offshore wind in Scotland, adopting a new mechanism which reduces risk and provides developers and investors with more certainty, would be more effective in encouraging offshore wind development. Finally, in order to overcome the most significant barrier, the grid, a more integrated and collaborative approach is required, which will share the burden of responsibility between the developer, Ofgem, and the National Grid. 相似文献
992.
Claire Liu Jin-Tae Kim Da Som Yang Donghwi Cho Seonggwang Yoo Surabhi R. Madhvapathy Hyoyoung Jeong Tianyu Yang Haiwen Luan Raudel Avila Jihun Park Yunyun Wu Kennedy Bryant Min Cho JiYong Lee Jay Young Kwak WonHyoung Ryu Yonggang Huang Ralph G. Nuzzo John A. Rogers 《Advanced functional materials》2023,33(34):2302256
Many recently developed classes of wireless, skin-interfaced bioelectronic devices rely on conventional thermoset silicone elastomer materials, such as poly(dimethylsiloxane) (PDMS), as soft encapsulating structures around collections of electronic components, radio frequency antennas and, commonly, rechargeable batteries. In optimized layouts and device designs, these materials provide attractive features, most prominently in their gentle, noninvasive interfaces to the skin even at regions of high curvature and large natural deformations. Past studies, however, overlook opportunities for developing variants of these materials for multimodal means to enhance the safety of the devices against failure modes that range from mechanical damage to thermal runaway. This study presents a self-healing PDMS dynamic covalent matrix embedded with chemistries that provide thermochromism, mechanochromism, strain-adaptive stiffening, and thermal insulation, as a collection of attributes relevant to safety. Demonstrations of this materials system and associated encapsulation strategy involve a wireless, skin-interfaced device that captures mechanoacoustic signatures of health status. The concepts introduced here can apply immediately to many other related bioelectronic devices. 相似文献
993.
Claire Husser Stéphane Vuilleumier Michael Ryckelynck 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(13):2205232
Nucleic acids are not only essential actors of cell life but also extremely appealing molecular objects in the development of synthetic molecules for biotechnological application, such as biosensors to report on the presence and concentration of a target ligand by emission of a measurable signal. In this work, FluorMango, a fluorogenic ribonucleic acid (RNA)-based biosensor specific for fluoride is introduced. The molecule consists of two RNA aptamer modules, a fluoride-specific sensor derived from the crcB riboswitch which changes its structure upon interaction with the target ion, and the light-up RNA Mango-III that emits fluorescence when complexed with a fluorogen. The two modules are connected by an optimized communication module identified by ultrahigh-throughput screening, which results in extremely high fluorescence of FluorMango in the presence of fluoride, and background fluorescence in its absence. The value and efficiency of this biosensor by direct monitoring of defluorinase activity in living bacterial cells is illustrated, and the use of this new tool in future screening campaigns aiming at discovering new defluorinase activities is discussed. 相似文献
994.
Nicolas Somers Florian Jean Marie Lasgorceix Giovanni Urruth Sandra Balvay Claire Gaillard Laurent Gremillard Anne Leriche 《Journal of the American Ceramic Society》2023,106(7):4061-4075
β-tricalcium phosphate (β-TCP, β-Ca3(PO4)2) is an attractive biomaterial for bone repair applications. However, its sintering and mechanical properties are limited by a problematic phase transition to α-TCP. Cationic doping of β-TCP is able to postpone the formation of α-TCP allowing higher sintering temperatures and better mechanical properties. The co-doping of β-TCP with Mg2+ and Sr2+ has already been studied in detail, but the addition of antibacterial cations (Ag+ and Cu2+) on the Mg–Sr β-TCP co-doped composition remains unexplored. Thus, two co-doped β-TCP compositions were realized by aqueous precipitation technique without any secondary phase and compared with undoped β-TCP: Mg–Sr (2.0–2.0 mol%) and Mg–Sr–Ag–Cu (2.0–2.0–0.1–0.1 mol%). Differential thermal analysis and dilatometry analyses showed a slight decrease of the β-TCP → α-TCP phase transition temperature for the Mg–Sr–Ag–Cu (2.0–2.0–0.1–0.1% mol) composition as compared to the Mg–Sr (2.0–2.0 mol%). However, both exhibited much higher transition temperatures than undoped β-TCP. The addition of Ag+ and Cu2+ slightly reduces the grain size after sintering compared to the Mg–Sr (2.0–2.0 mol%) and the undoped compositions. The co-doped compositions also exhibited improved mechanical properties, specifically a higher Vickers hardness and elastic modulus. Finally, cell proliferation assays showed that the presence of dopants, even Ag+ and Cu2+, does not affect the survival and proliferation of cells. Thus, the use of Mg2+, Sr2+, Ag+, and Cu2+ co-doped β-TCP could be very promising for biomedical applications due to the improvements of these dopants on the thermal stability and mechanical and biological properties. 相似文献
995.
996.
Measurements are reported on the cure and physical properties of an epoxy resin created using a functionalised nanosilica filler. The filled bisphenol A epoxy (Nanopox A410) contained 40 wt% silica nanoparticles and was blended with two bisphenol A resins of molecular weights of 355 and 1075 g mol?1, respectively. Cure was achieved using 3,3‐diaminodiphenylsulfone. The functionality of the mixture containing the epoxy nanoparticles was determined using NMR analysis. Cure times showed a progressive decrease with increasing silica level. Dynamic mechanical thermal analysis showed a decrease in the value of the glass transition temperature (Tg) with increasing silica level. Tg was further studied using differential scanning calorimetry. The ability of the nanosilica to create a stable network structure was demonstrated by the variation of the high‐temperature modulus with silica composition. Thermomechanical analysis carried out below and above Tg showed a progressive decrease in the expansion coefficients with increasing silica level, indicating the effectiveness of the functionalised silica nanoparticles in forming a network. The network formed during cure in the nano‐modified epoxy is unable to undergo the densification possible in the pure resin material and explains the observed lowering of Tg with increasing nanosilica content. Copyright © 2009 Society of Chemical Industry 相似文献
997.
The formulation of optimal mixtures with generalized disjunctive programming: A solvent design case study 下载免费PDF全文
Suela Jonuzaj Paul T. Akula Polyxeni‐Margarita Kleniati Claire S. Adjiman 《American Institute of Chemical Engineers》2016,62(5):1616-1633
Systematic approaches for the design of mixtures, based on a computer‐aided mixture/blend design (CAMbD) framework, have the potential to deliver better products and processes. In most existing methodologies the number of mixture ingredients is fixed (usually a binary mixture) and the identity of at least one compound is chosen from a given set of candidate molecules. A novel CAMbD methodology is presented for formulating the general mixture design problem where the number, identity and composition of mixture constituents are optimized simultaneously. To this end, generalized disjunctive programming is integrated into the CAMbD framework to formulate the discrete choices. This generic methodology is applied to a case study to find an optimal solvent mixture that maximizes the solubility of ibuprofen. The best performance in this case study is obtained with a solvent mixture, showing the benefit of using mixtures instead of pure solvents to attain enhanced behavior. © 2016 The Authors AIChE Journal published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers AIChE J, 62: 1616–1633, 2016 相似文献
998.
Pamela McCall Claire E. Adams Jennifer M. Willder Lindsay Bennett Tahir Qayyum Clare Orange Mark A. Underwood Joanne Edwards 《International journal of molecular sciences》2013,14(8):16656-16671
We previously reported that AR phosphorylation at serine 213 was associated with poor outcome and may contribute to prostate cancer development and progression. This study investigates if specific AR phosphorylation sites have differing roles in the progression of hormone naïve prostate cancer (HNPC) to castrate resistant disease (CRPC). A panel of phosphospecific antibodies were employed to study AR phosphorylation in 84 matched HNPC and CRPC tumours. Immunohistochemistry measured Androgen receptor expression phosphorylated at serine residues 94 (pAR94), 308 (pAR308), 650(pAR650) and 791 (pAR791). No correlations with clinical parameters were observed for pAR94 or pAR650 in HNPC or CRPC tumours. In contrast to our previous observation with serine 213, high pAR308 is significantly associated with a longer time to disease specific death (p = 0.011) and high pAR791 expression significantly associated with a longer time to disease recurrence (p = 0.018) in HNPC tumours and longer time to death from disease recurrence (p = 0.040) in CRPC tumours. This observation in CRPC tumours was attenuated in high apoptotic tumours (p = 0.022) and low proliferating tumours (p = 0.004). These results demonstrate that understanding the differing roles of AR phosphorylation is necessary before this can be exploited as a target for castrate resistant prostate cancer. 相似文献
999.
Sylvie Tordjman Imen Najjar Eric Bellissant George M. Anderson Marianne Barburoth David Cohen Nemat Jaafari Olivier Schischmanoff Rémi Fagard Enas Lagdas Solenn Kermarrec Sophie Ribardiere Michel Botbol Claire Fougerou Guillaume Bronsard Julie Vernay-Leconte 《International journal of molecular sciences》2013,14(10):20508-20542
Abnormalities in melatonin physiology may be involved or closely linked to the pathophysiology and behavioral expression of autistic disorder, given its role in neurodevelopment and reports of sleep-wake rhythm disturbances, decreased nocturnal melatonin production, and beneficial therapeutic effects of melatonin in individuals with autism. In addition, melatonin, as a pineal gland hormone produced from serotonin, is of special interest in autistic disorder given reported alterations in central and peripheral serotonin neurobiology. More specifically, the role of melatonin in the ontogenetic establishment of circadian rhythms and the synchronization of peripheral oscillators opens interesting perspectives to ascertain better the mechanisms underlying the significant relationship found between lower nocturnal melatonin excretion and increased severity of autistic social communication impairments, especially for verbal communication and social imitative play. In this article, first we review the studies on melatonin levels and the treatment studies of melatonin in autistic disorder. Then, we discuss the relationships between melatonin and autistic behavioral impairments with regard to social communication (verbal and non-verbal communication, social interaction), and repetitive behaviors or interests with difficulties adapting to change. In conclusion, we emphasize that randomized clinical trials in autism spectrum disorders are warranted to establish potential therapeutic efficacy of melatonin for social communication impairments and stereotyped behaviors or interests. 相似文献
1000.
Syam Nair Henrik Hagberg Rajanikant Krishnamurthy Claire Thornton Carina Mallard 《International journal of molecular sciences》2013,14(7):13858-13872
Perinatal brain damage underlies an important share of motor and neurodevelopmental disabilities, such as cerebral palsy, cognitive impairment, visual dysfunction and epilepsy. Clinical, epidemiological, and experimental studies have revealed that factors such as inflammation, excitotoxicity and oxidative stress contribute considerably to both white and grey matter injury in the immature brain. A member of the death associated protein kinase (DAPk) family, DAPk1, has been implicated in cerebral ischemic damage, whereby DAPk1 potentiates NMDA receptor-mediated excitotoxicity through interaction with the NR2BR subunit. DAPk1 also mediate a range of activities from autophagy, membrane blebbing and DNA fragmentation ultimately leading to cell death. DAPk mRNA levels are particularly highly expressed in the developing brain and thus, we hypothesize that DAPk1 may play a role in perinatal brain injury. In addition to reviewing current knowledge, we present new aspects of the molecular structure of DAPk domains, and relate these findings to interacting partners of DAPk1, DAPk-regulation in NMDA-induced cerebral injury and novel approaches to blocking the injurious effects of DAPk1. 相似文献