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251.
252.
Vishnu Vijayakumar Yuhan Zhong Viktoriia Untilova Mounib Bahri Laurent Herrmann Laure Biniek Nicolas Leclerc Martin Brinkmann 《Liver Transplantation》2019,9(24)
Here, an effective design strategy of polymer thermoelectric materials based on structural control in doped polymer semiconductors is presented. The strategy is illustrated for two archetypical polythiophenes, e.g., poly(2,5‐bis(3‐dodecyl‐2‐thienyl)thieno[3,2‐b]thiophene) (C12‐PBTTT) and regioregular poly(3‐hexylthiophene) (P3HT). FeCl3 doping of aligned films results in charge conductivities up to 2 × 105 S cm?1 and metallic‐like thermopowers similar to iodine‐doped polyacetylene. The films are almost optically transparent and show strongly polarized near‐infrared polaronic bands (dichroic ratio >10). The comparative study of structure–property correlations in P3HT and C12‐PBTTT identifies three conditions to obtain conductivities beyond 105 S cm?1: i) achieve high in‐plane orientation of conjugated polymers with high persistence length; ii) ensure uniform chain oxidation of the polymer backbones by regular intercalation of dopant molecules in the polymer structure without disrupting alignment of π‐stacked layers; and iii) maintain a percolating nanomorphology along the chain direction. The highly anisotropic conducting polymer films are ideal model systems to investigate the correlations between thermopower S and charge conductivity σ. A scaling law S ∝ σ?1/4 prevails along the chain direction, but a different S ∝ ?ln(σ) relation is observed perpendicular to the chains, suggesting different charge transport mechanisms. The simultaneous increase of charge conductivity and thermopower along the chain direction results in a substantial improvement of thermoelectric power factors up to 2 mW m?1 K?2 in C12‐PBTTT. 相似文献
253.
254.
Steven A. Li Melissa M. Cadelis Kenneth Sue Marine Blanchet Nicolas Vidal Jean Michel Brunel Marie-Lise Bourguet-Kondracki Brent R. Copp 《Bioorganic & medicinal chemistry》2019,27(10):2090-2099
The combination of increased incidence of drug-resistant strains of bacteria and a lack of novel drugs in development creates an urgency for the search for new antimicrobials. Initial screening of compounds from an in-house library identified two 6-bromoindolglyoxylamide polyamine derivatives (3 and 4) that exhibited intrinsic antimicrobial activity towards Gram-positive bacteria, Staphylococcus aureus and S. intermedius with polyamine 3 also displaying in vitro antibiotic enhancing properties against the resistant Gram-negative bacterium Pseudomonas aeruginosa. A series of 6-bromo derivatives (5–15) were prepared and biologically evaluated, identifying analogues with enhanced antibacterial activity towards Escherichia coli and with moderate to excellent antifungal properties. Polyamine 3, which includes a spermine chain, was the most potent of the series – its mechanism of action was attributed to rapid membrane permeabilization and depolarization in both Gram-positive and Gram-negative bacteria. 相似文献
255.
Vilizzi Lorenzo Copp Gordon H. Adamovich Boris Almeida David Chan Joleen Davison Phil I. Dembski Samuel Ekmekçi F. Güler Ferincz Árpád Forneck Sandra C. Hill Jeffrey E. Kim Jeong-Eun Koutsikos Nicholas Leuven Rob S. E. W. Luna Sergio A. Magalhães Filomena Marr Sean M. Mendoza Roberto Mourão Carlos F. Neal J. Wesley Onikura Norio Perdikaris Costas Piria Marina Poulet Nicolas Puntila Riikka Range Inês L. Simonović Predrag Ribeiro Filipe Tarkan Ali Serhan Troca Débora F. A. Vardakas Leonidas Verreycken Hugo Vintsek Lizaveta Weyl Olaf L. F. Yeo Darren C. J. Zeng Yiwen 《Reviews in Fish Biology and Fisheries》2019,29(3):529-568
Reviews in Fish Biology and Fisheries - The freshwater Fish Invasiveness Screening Kit (FISK) has been applied in 35 risk assessment areas in 45 countries across the six inhabited continents (11... 相似文献
256.
257.
Peter W. Glynn Brian Coffman Karim Primov D. Abigail Renegar Julie Gross Patricia Blackwelder Nicolas Martinez Joshua Dominguez Jeongran Vanderwoude Bernhard M. Riegl 《Invertebrate Biology》2019,138(3)
Reproductive structures, modes, and seasonal patterns of size–class abundances are examined in two benthic platyctene (Family Coeloplanidae) ctenophore species present in dissimilar shallow marine environments in subtropical southeast Florida. Coeloplana waltoni, a minute (1–3 mm body length) epizoic associate of octocorals, occurs in exposed environments often under turbulent conditions, and Vallicula multiformis (2–10 mm) commonly occurs epiphytically on macroalgae in protected, calm‐water environments. Reproductive activity in C. waltoni is most active during the warm‐water summer season (June–October); gonadal development in V. multiformis occurs year‐round, and is most pronounced during sea‐warming periods in late spring (May) and late summer to early autumn (August–October), with release of cydippid larvae. Both species are hermaphroditic brooders, exhibiting paedogenesis (early gonadal development) at body lengths approximately one‐third (Coeloplana) to one‐sixth (Vallicula) of maximum adult size. Juvenile individuals (<0.6 mm) increased in abundance in C. waltoni during the summer reproductive period, and large (≥1 mm) pink‐colored individuals comprised 50% or more of samples from July through September. Seasonal abundance of gravid individuals and the timing of cydippid larval release in V. multiformis did not correspond closely with juvenile or adult population densities. Asexual fragmentation occurred in both ctenophore species, but was observed more frequently in individuals of V. multiformis. This asexual mode of reproduction probably accounted in part for the discordance between ctenophore abundances and larval recruitment events by sexual means. Morphological structures and behaviors associated with reproduction are described in this study. Uncommon images of reproductive products (gametes, embryos, larvae), spawning events, brooding, and asexual fragmentation are included, some for the first time in the published literature. 相似文献
258.
Kuznetsova A. A. Kladova O. A. Barthes Nicolas P. F. Michel Benoit Y. Burger Alain Fedorova O. S. Kuznetsov N. A. 《Russian Journal of Bioorganic Chemistry》2019,45(6):591-598
Russian Journal of Bioorganic Chemistry - DNA-substrates containing fluorescent DNA base analogs are widely used to study protein–nucleic acid interactions. In the case of DNA-recognizing... 相似文献
259.
Pacheco Nicolas Orellana-Saez Matias Pepczynska Marzena Enrione Javier Bassas-Galia Monica Borrero-de Acuña Jose M. Zacconi Flavia C. Marcoleta Andrés E. Poblete-Castro Ignacio 《Journal of industrial microbiology & biotechnology》2019,46(8):1139-1153
Journal of Industrial Microbiology & Biotechnology - Extreme environments are a unique source of microorganisms encoding metabolic capacities that remain largely unexplored. In this work, we... 相似文献
260.
Laurent Montagano Shawn J. Leroux Marie‐Andre Giroux Nicolas Lecomte 《Ecology letters》2019,22(2):265-274
Material and energy flows among ecosystems can directly and indirectly drive ecosystem functions. Yet, how populations of consumers respond to allochthonous inputs at a macroecological scale is still unclear. Using a meta‐analysis spanning several biomes, we show that the abundance of recipient populations is 36–57% larger with increased allochthonous inputs. The strength of direct effects on the recipients of these inputs as well as the indirect effects on the consumers of these recipients (i.e. ascending indirect effects) are constant across a latitudinal gradient spanning subtropical, arid, temperate, boreal and arctic ecosystems. However, indirect effect on the in situ resources of the input recipient (i.e. descending indirect effects) decreases with latitude. Our results suggest that the influence of allochthonous inputs can vary across large‐scale gradients of ecosystem productivity and may be driven by the types of trophic interactions within recipient food webs. 相似文献