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1.
R. Paxton Thedford Peter A. Beaucage Ethan M. Susca Corson A. Chao Katja C. Nowack Robert B. Van Dover Sol M. Gruner Ulrich Wiesner 《Advanced functional materials》2021,31(23):2100469
Mesoscale order can lead to emergent properties including phononic bandgaps or topologically protected states. Block copolymers offer a route to mesoscale periodic architectures, but their use as structure directing agents for metallic materials has not been fully realized. A versatile approach to mesostructured metals via bulk block copolymer self-assembly derived ceramic templates, is demonstrated. Molten indium is infiltrated into mesoporous, double gyroidal silicon nitride templates under high pressure to yield bulk, 3D periodic nanocomposites as free-standing monoliths which exhibit emergent quantum-scale phenomena. Vortices are artificially introduced when double gyroidal indium metal behaves as a type II superconductor, with evidence of strong pinning centers arrayed on the order of the double gyroid lattice size. Sample behavior is reproducible over months, showing high stability. High pressure infiltration of bulk block copolymer self-assembly based ceramic templates is an enabling tool for studying high-quality metals with previously inaccessible architectures, and paves the way for the emerging field of block-copolymer derived quantum metamaterials. 相似文献
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3.
Thomas Frissen Erkan Toguslu Pieter Van Ostaeyen Leen dHaenens 《Telematics and Informatics》2018,35(2):491-503
The current study set out to investigate to what extent ISIS is bolstering its jihadist ideology on a ‘cut-and-paste’ or ‘cherry-picked’ version of Islam in their renowned online propaganda magazine Dabiq. The main objective was to examine in a systematic and quantitative way to what extent ISIS utilizes the Koran in an atomistic, truncated and tailored manner to bolster its religious legitimacy. A total of 15 issues of Dabiq and 700 Koranic references were scrutinized. By means of a quantitative analysis we developed an innovative taxonomy of Koranic chapters and verses (i.e. surahs and ayat, respectively) on the basis of their appearance in Dabiq. Our large-scale data analysis provide consistent empirical evidence for severe decontextualization practices of the Koran in three ways: (1) a thin, Medinan-dominated religious layer, (2) ayah mutilation, and (3) clustered versus exclusive mentions. Limitations and implications for future research, policy makers and CVE initiatives are discussed. 相似文献
4.
Beukes Pierre C. Gregorini Pablo Cameron Keith Attwood Graeme T. 《Nutrient Cycling in Agroecosystems》2020,117(1):1-12
Nutrient Cycling in Agroecosystems - The nitrogen (N) fertilizer application rate (kg ha?1 year?1) in pastoral dairy systems affects the flow of N through the soil,... 相似文献
5.
Harry G. Sherman Jacqueline M. Hicks Akhil Jain Jeremy J. Titman Prof. Cameron Alexander Snow Stolnik Frankie J. Rawson 《Chembiochem : a European journal of chemical biology》2019,20(8):1008-1013
A model cancer cell line was used to initiate polymerisation of pyrrole to form the conducting material polypyrrole. The polymerisation was shown to occur through the action of cytosolic exudates rather than that of the membrane redox sites that normally control the oxidation state of iron as ferricyanide or ferrocyanide. The data demonstrate for the first time that mammalian cells can be used to initiate synthesis of conducting polymers and suggest a possible route to detection of cell damage and/or transcellular processes through in situ and amplifiable signal generation. 相似文献
6.
ABSTRACTThis article explores how private owners can protect bodies of water through private property rights. It compares the use of conventional property rights in the Netherlands and New Zealand with a novel approach whereby a New Zealand river owns itself. 相似文献
7.
M. Neupane J.L. Hutchison C.P. Van Tassell P.M. VanRaden 《Journal of dairy science》2021,104(8):8959-8965
Differences in breeds and sire lines suggest the presence of a genetic component for heifer livability (HLIV). Genomic evaluation for this trait can increase profitability and improve animal health and welfare. Evaluations for HLIV were examined from 3,362,499 calf data records from heifers of all breeds born from 2009 to 2016. Data were obtained from the national cooperator database maintained by the Council on Dairy Cattle Breeding (https://www.uscdcb.com/). The total number of deaths reported was 134,753 (4.01%), which included herds with death loss between 1.5 and 25.5%. Age at death was evaluated and ranged from >2 d of age until the heifer left the herd, with a maximum of 18 mo of age. Records were not included until 3 yr after the birthdate so that live status of contemporaries could be confirmed by a calving date for those animals. Deaths observed until 2 d after birth were considered to be a stillbirth rather than a failure of HLIV. The scale used for analysis of HLIV was 0 (died) or 100 (live), and the heritability estimate was 0.7% based on sire model with restricted maximum likelihood estimation. Genomic predicted transmitting abilities for Holstein ranged from ?1.6% to +1.6% with a standard deviation of 0.5%, and genomic predicted transmitting abilities for Jersey ranged from ?0.5% to +0.5% with a standard deviation of 0.2%. The mean overall death loss was about 4%. Reliabilities of genomic predictions for young animals averaged 46% for Holsteins and 30% for Jerseys, and corresponding traditional parent average reliabilities averaged 16% and 12%, respectively. Correlations of HLIV were 0.44 with productive life, 0.18 to 0.22 with yield traits, and 0.29 with early first calving on proven Holstein bulls. The HLIV trait had a favorable genetic trend in recent years, likely because of the indirect selection associated with the correlated traits. The trait HLIV should receive 1% of emphasis on the Lifetime Net Merit index, resulting in economic progress worth $50,000/yr. By encouraging more comprehensive recording on calf mortality, the reliabilities of genetic predictions could increase significantly. 相似文献
8.
Kaitlin A. Doucette Prangthong Chaiyasit Donn L. Calkins Kayli N. Martinez Cameron Van Cleave Callan A. Knebel Anan Tongraar Debbie C. Crans 《International journal of molecular sciences》2021,22(1)
The interactions of amino acids and peptides at model membrane interfaces have considerable implications for biological functions, with the ability to act as chemical messengers, hormones, neurotransmitters, and even as antibiotics and anticancer agents. In this study, glycine and the short glycine peptides diglycine, triglycine, and tetraglycine are studied with regards to their interactions at the model membrane interface of Aerosol-OT (AOT) reverse micelles via 1H NMR spectroscopy, dynamic light scattering (DLS), and Langmuir trough measurements. It was found that with the exception of monomeric glycine, the peptides prefer to associate between the interface and bulk water pool of the reverse micelle. Monomeric glycine, however, resides with the N-terminus in the ordered interstitial water (stern layer) and the C-terminus located in the bulk water pool of the reverse micelle. 相似文献
9.
Reece N. Oosterbeek Kalliope I. Margaronis Xiang C. Zhang Serena M. Best Ruth E. Cameron 《Journal of the European Ceramic Society》2021,41(1):901-911
Phosphate glasses for bioresorbable implants display dissolution rates that vary significantly with composition, however currently their mechanisms of dissolution are not well understood. Based on this systematic study we present new insights into these mechanisms. Two-stage dissolution was observed, with time dependence initially parabolic and later linear, and a two-stage model was developed to describe this behaviour. Dissolution was accelerated by lower Ca concentration in the glass, and lower pH in the dissolution medium. A new dissolution mechanism is proposed, involving an initial stage where diffusion-controlled formation of a conversion layer occurs. Once the conversion layer is stabilised, layer dissolution reactions become rate-limiting. Under this mechanism the transition time is sensitive to the nature of the conversion layer and solution conditions. These results reveal the dependence of P2O5–CaO–Na2O glass dissolution on solution pH, and provide new insight into the dissolution mechanisms, particularly regarding the transition between the two dissolution stages. 相似文献
10.
E. Willems M. Turon-Vinas B. Camargo dos Santos B. Van Hooreweder F. Zhang B. Van Meerbeek J. Vleugels 《Journal of the European Ceramic Society》2021,41(10):5292-5306
The possibility of additive manufacturing of ceramics has been reported widely in scientific literature. This study investigates the potential of direct inkjet printing or material jetting of 3Y-TZP ceramics by assessing the microstructure and mechanical properties of the sintered printed parts. The technique allows to print in layers of 10.5 μm, with an as-printed green density of 58 % and nearly fully sintered density of 6.03 ± 0.1 g/cm3 (99.7 % TD). The dimensions of the green and sintered parts were highly accurate but showed an anisotropic roughness in function of the building direction, mainly due to the support structures. The biaxial bending and 4-point bending strength of the sintered material was found to be substantially higher in the XY direction than in the building (Z) direction. SEM and X-Ray computed tomography revealed the presence of delamination cracks, agglomerates and spherical pores, which were identified as fracture origins on fractured surfaces. 相似文献