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81.
Here, it is investigated whether an energetic cascade between mixed and pure regions assists in suppressing recombination losses in non‐fullerene acceptor (NFA)‐based organic solar cells. The impact of polymer‐NFA blend composition upon morphology, energetics, charge carrier recombination kinetics, and photocurrent properties are studied. By changing film composition, morphological structures are varied from consisting of highly intermixed polymer‐NFA phases to consisting of both intermixed and pure phase. Cyclic voltammetry is employed to investigate the impact of blend morphology upon NFA lowest unoccupied molecular orbital (LUMO) level energetics. Transient absorption spectroscopy reveals the importance of an energetic cascade between mixed and pure phases in the electron–hole dynamics in order to well separate spatially localized electron–hole pairs. Raman spectroscopy is used to investigate the origin of energetic shift of NFA LUMO levels. It appears that the increase in NFA electron affinity in pure phases relative to mixed phases is correlated with a transition from a relatively planar backbone structure of NFA in pure, aggregated phases, to a more twisted structure in molecularly mixed phases. The studies focus on addressing whether aggregation‐dependent acceptor LUMO level energetics are a general design requirement for both fullerene and NFAs, and quantifying the magnitude, origin, and impact of such energetic shifts upon device performance.  相似文献   
82.
The purpose of this study was to examine the effects of amino acid supplementation on muscular strength, power, and high-intensity endurance during short-term resistance training overreaching. Seventeen resistance-trained men were randomly assigned to either an amino acid (AA) or placebo (P) group and underwent 4 weeks of total-body resistance training consisting of two 2-week phases of overreaching (phase 1: 3 x 8-12 repetitions maximum [RM], 8 exercises; phase 2: 5 x 3-5 RM, 5 exercises). Muscle strength, power, and high-intensity endurance were determined before (T1) and at the end of each training week (T2-T5). One repetition maximum squat and bench press decreased at T2 in P (5.2 and 3.4 kg, respectively) but not in AA, and significant increases in 1 RM squat and bench press were observed at T3-T5 in both groups. A decrease in the ballistic bench press peak power was observed at T3 in P but not AA. The fatigue index during the 20-repetition jump squat assessment did not change in the P group at T3 and T5 (fatigue index = 18.6 and 18.3%, respectively) whereas a trend for reduction was observed in the AA group (p = 0.06) at T3 (12.8%) but not T5 (15.2%; p = 0.12). These results indicate that the initial impact of high-volume resistance training overreaching reduces muscle strength and power, and it appears that these reductions are attenuated with amino acid supplementation. In addition, an initial high-volume, moderate-intensity phase of overreaching followed by a higher intensity, moderate-volume phase appears to be very effective for enhancing muscle strength in resistance-trained men.  相似文献   
83.
Recent social science scholarship has employed the term “pharmaceuticalization” in analyses of the production, circulation and use of drugs. In this paper, we seek to open up further discussion of the scope, limits and potential of this as an analytical device through consideration of the role of law and legal processes in directing pharmaceutical flows. To do so, we synthesize a range of empirical and conceptual work concerned with the relationships between access to medicines and intellectual property law. This paper suggests that alongside documenting the expansion or reduction in demand for particular drugs, analysts of pharmaceuticalization attend to the ways in which socio-legal developments change (or not) the identities of drugs, and the means through which they circulate and come to be used by states and citizens. Such scholarship has the potential to more precisely locate the biopolitical processes that shape international agendas and targets, form markets, and produce health.  相似文献   
84.
Corydalis mucronata Franch., illustrated here, is among several Corydalis collected by Père Armand David in Moupine (now Baoxing ) in western Sichuan. It can be a conspicuous plant, forming large populations on shady, wet slopes. Though introduced to England over 20 years ago, it is still rare in gardens. Suggestions for its successful cultivation are given.  相似文献   
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Summary.  Fritillaria karelinii Fisch. ex D.Don ( Liliaceae ) is illustrated. Its relationships with other species and the position of subgenus Rhinopetalum are discussed. Instructions for its cultivation are given.  相似文献   
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Specific interactions between lipids and membrane proteins have been observed in recent high-resolution crystal structures of membrane proteins. A number of cytochrome oxidase structures were analyzed, along with many amino acid sequences of membrane-spanning regions aligned according to their location in the membrane. The results reveal conservation of lipid-binding sites and of the residues that form them. These studies imply that bound lipids have important roles that are crucial to the assembly, structure, or activity of the protein. Evidence for some of these roles in subunit interactions, membrane insertion, and protein-protein complex formation is reviewed.  相似文献   
90.
Paeonia parnassica is illustrated, its habitat is shown and suggestions for its successful cultivation are given.  相似文献   
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