Partial structure factors derived from coarse-grained phase-separation dynamics on a disordered lattice with density fluctuations

The simplest and most time-efficient phase-separation dynamics simulations are carried out on a disordered lattice to calculate the partial structure factors of coarse-grained A-B binary mixtures. The typical coarse-grained phase-separation models use regular lattices and can describe the local concentrations but cannot describe both local density and concentration fluctuations. To introduce fluctuation for local density in the model, the particle positions from a hard sphere fluid model are determined as disordered lattice points for the model. Then we place the local order parameter as the difference of the concentrations of A and B components on each lattice point. The concentration at each lattice point is time-evolved by discrete equations derived from the Cahn-Hilliard equation. From both fluctuations, Bhatia and Thornton’s structure factor can be accurately calculated. The structure factor for concentration fluctuations at the large wavenumber region gives us the correct mean concentrations of the components. Using the mean concentrations, partial structure factors can be converted from three of Bhatia and Thornton’s structure factors. The present model and procedures can provide a means of analysing the structural properties of many materials that exhibit complex morphological changes.

Cyanogenesis in Aralia spinosa (Araliaceae)

A systematic survey of Aralia spinosa (Araliaceae), covering an entire growing season and including aboveground organs at various developmental stages, revealed that only about half of all samples collected showed cyanogenesis. Cyanogenesis was detected in inflorescences and leaves but is apparently restricted to certain harvest times or developmental stages. The structurally unusual triglochinin, characterized by a hex-2-enedioic acid partial structure, was the only cyanogenic glycoside detected. This is the first description of triglochinin in this species and in the family of Araliaceae. Triglochinin is biogenetically derived from tyrosine, which is in good agreement with the few cyanogenic glycosides previously detected in members of the Araliaceae family. Triglochinin was identified, characterized, and quantified by modern chromatographic methods, and the amount of enzymatically releasable hydrocyanic acid was determined qualitatively and quantitatively. Two isomers of triglochinin were detected chromatographically at minor levels. The isomeric pattern agreed well with literature data from other triglochinin-containing plants. This was confirmed in the two species, Triglochin maritima and Thalictrum aquilegiifolium, which were comparatively studied. In the case of A. spinosa, inflorescence buds harvested in July showed the highest content of triglochinin, just under 0.2% on a dry weight basis. The detection of triglochinin adds to the knowledge of toxicological properties and the dereplication of U(H)PLC/MS² data provides a comprehensive phytochemical profile of A. spinosa.

The Microstructure in an Al–Ti Alloy Melt: The Wulff Cluster Model from a Partial Structure Factor

In the present work, the Wulff cluster model—which has been proven to successfully describe pure metals, homogeneous alloys, and eutectic alloys—has been extended to complex binary Al80Ti20 alloys, containing intermetallic compounds. In our model, the most probable structure in metallic melts should have the shape determined by Wulff construction within the crystal structure inside, and the cluster’s size could be measured by pair distribution function. For Al80Ti20 binary alloy, three different types of clusters (Al cluster, Al3Ti cluster, and Ti cluster) were proposed. Their contributions in XRD results are investigated by a comparison with the partial XRD pattern. Ti–Ti and Al–Ti partial structural factors are completely contributed by a pure Ti cluster and an Al3Ti cluster, respectively. Al–Al partial structural factor is contributed not only by a pure Al cluster but is also related to part of the Al3Ti cluster. The simulated XRD curve shows a good agreement with the experimental partial I(θ), including the peak position, width, and relative intensity.

Synthesis and Structure-Activity Relationships of New 2-Phenoxybenzamides with Antiplasmodial Activity

The 2-phenoxybenzamide 1 from the Medicines for Malaria Venture Malaria Box Project has shown promising multi-stage activity against different strains of P. falciparum. It was successfully synthesized via a retrosynthetic approach. Subsequently, twenty-one new derivatives were prepared and tested for their in vitro activity against blood stages of the NF54 strain of P. falciparum. Several insights into structure-activity relationships were revealed. The antiplasmodial activity and cytotoxicity of compounds strongly depended on the substitution pattern of the anilino partial structure as well as on the size of substituents. The diaryl ether partial structure had further impacts on the activity. Additionally, several physicochemical and pharmacokinetic parameters were calculated (log P, log D7.4 and ligand efficiency) or determined experimentally (passive permeability and CYP3A4 inhibition). The tert-butyl-4-{4-[2-(4-fluorophenoxy)-3-(trifluoromethyl)benzamido]phenyl}piperazine-1-carboxylate possesses high antiplasmodial activity against P. falciparum NF54 (PfNF54 IC50 = 0.2690 µM) and very low cytotoxicity (L-6 cells IC50 = 124.0 µM) resulting in an excellent selectivity index of 460. Compared to the lead structure 1 the antiplasmodial activity was improved as well as the physicochemical and some pharmacokinetic parameters.

Partial-Structure-Oriented Work-Energy Theorem Based Characteristic Mode Theory for Yagi-Uda Array Antennas

Partial-structure-oriented work-energy theorem (WET) governing the work-energy transformation process of Yagi-Uda array antennas is derived. Driving power as the source to sustain a steady work-energy transformation is introduced. Employing WET and driving power, the essential difference between the working mechanisms of scattering objects and Yagi-Uda array antennas is revealed. The difference exposes that the conventional characteristic mode theory (CMT) for scattering objects cannot be directly applied to Yagi-Uda array antennas. Under WET framework, this paper proposes a generalized CMT for Yagi-Uda antennas. By orthogonalizing driving power operator (DPO), the WET-based CMT can construct a set of energy-decoupled characteristic modes (CMs) for an objective Yagi-Uda antenna, and then can provide an effective modal analysis for the Yagi-Uda antenna. In addition, a uniform interpretation for the physical meaning of the characteristic values / modal significances (MSs) of metallic, material, and metal-material composite Yagi-Uda antennas is also obtained by employing the WET-based modal decomposition and the field-current interaction expression of driving power.

Partial-Structure-Oriented Work-Energy Theorem Based Characteristic Mode Theory for Yagi-Uda Array Antennas

Partial-structure-oriented work-energy theorem (WET) governing the work-energy transformation process of Yagi-Uda array antennas is derived. Driving power as the source to sustain a steady work-energy transformation is introduced. Employing WET and driving power, the essential difference between the working mechanisms of scattering objects and Yagi-Uda array antennas is revealed. The difference exposes that the conventional characteristic mode theory (CMT) for scattering objects cannot be directly applied to Yagi-Uda array antennas. Under WET framework, this paper proposes a generalized CMT for Yagi-Uda antennas. By orthogonalizing driving power operator (DPO), the WET-based CMT can construct a set of energy-decoupled characteristic modes (CMs) for an objective Yagi-Uda antenna, and then can provide an effective modal analysis for the Yagi-Uda antenna. In addition, a uniform interpretation for the physical meaning of the characteristic values / modal significances (MSs) of metallic, material, and metal-material composite Yagi-Uda antennas is also obtained by employing the WET-based modal decomposition and the field-current interaction expression of driving power.

The boson peak and the first sharp diffraction peak in (As2S3)x(GeS2)1–x glasses

The parameters of the boson peak (BP) and the first sharp diffraction peak (FSDP) in (As2S3)x(GeS2)1x glasses measured using high-resolution Raman spectroscopy and high-energy synchrotron X-ray diffraction measurements are examined as a function of x. It has been found that there is no correlation between the positions of BP and FSDP. The BP position shows a nonlinear composition behavior with a maximum at about x = 0.4, whereas the FSDP position changes virtually linearly with x. The intensities of both BP and FSDP show nonlinear composition dependences with the slope changes at x = 0.4, although there is no direct proportionality. Analysis of the partial structure factors for the glasses with x = 0.2, 0.4 and 0.6 obtained in another study has shown that the cation-cation atomic pairs of Ge–Ge, Ge–As and As–As make the largest contribution to FSDP, where the Ge–Ge and Ge–As pairs are dominant.

Low on trust, high on use datafied media, trust and everyday life

This article explores yet another paradox – aside from the privacy paradox – related to the datafication of media: citizens trust least the media they use most It investigates the role that daily life plays in shaping the trust that citizens place in datafied media. The study reveals five sets of heuristics guiding the trust assessments of citizens: (1) characteristics of media organisations, (2) old media standards, (3) context of use and purpose, (4) experiences of datafication and (5) understandings of datafication. The article discusses the use of these heuristics and the value that everyday life holds in assessing trust in datafied media. It concludes that, guided by a partial ‘structure of perception’ and enticed into trusting datafied media in the context of their daily lives, citizens may be highly concerned by the datafication of media but use them nevertheless.

Big Data: truth, quasi-truth or post-truth?

In this paper we investigate if sentences presented as the result of the application of statistical models and artificial intelligence to large volumes of data – the so-called ‘Big Data’ – can be characterized as semantically true, or as quasi-true, or even if such sentences can only be characterized as probably quasi-false and, in a certain way, post-true; that is, if, in the context of Big Data, the representation of a data domain can be configured as a total structure, or as a partial structure provided with a set of sentences assumed to be true, or if such representation cannot be configured as a partial structure provided with a set of sentences assumed to be true.