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Although being an old concern, phosphate analysis is still a tremendous challenge. While many different experimental techniques are found in the literature, very few use powder X-ray diffraction (PXRD) patterns for quantitative phase analysis of different phosphate types. Our measurements performed in four commercial samples of diammonium hydrogen phosphate ((NH4)2HPO4) (DAP) show the existence of phosphate contamination mixtures, such as ammonium dihydrogen phosphate (NH4H2PO4) (ADP). The larger the amount of ADP, the larger the microstrain induced in the DAP phase, which impacts both the aggregation of the nanoparticles in solution and the final anticancer activity of the nanostructure. This study shows that PXRD is an excellent technique for quantitative phase analysis to determine the presence and amount of phosphate contamination in diammonium hydrogen phosphate samples.
Programmable active matter (PAM) combines information processing and energy transduction. The physical embodiment of information could be the direction of magnetic spins, a sequence of molecules, the concentrations of ions, or the shape of materials. Energy transduction involves the transformation of chemical, magnetic, or electrical energies into mechanical energy. A major class of PAM consists of material systems with many interacting units. These units could be molecules, colloids, microorganisms, droplets, or robots. Because the interaction among units determines the properties and functions of PAMs, the programmability of PAMs is largely due to the programmable interactions. Here, we review PAMs across scales, from supramolecular systems to macroscopic robotic swarms. We focus on the interactions at different scales and describe how these (often local) interactions give rise to global properties and functions. The research on PAMs will contribute to the pursuit of generalised crystallography and the study of complexity and emergence. Finally, we ponder on the opportunities and challenges in using PAM to build a soft-matter brain.
Pb–Zr–Ti–O (PZT) perovskites span a large solid-solution range and have found widespread use due to their piezoelectric and ferroelectric properties that also span a large range. Crystal structure analysis via Rietveld refinement facilitates materials analysis via the extraction of the structural parameters. These parameters, often obtained as a function of an additional dimension (e.g., pressure), can help to diagnose materials response within a use environment. Often referred to as “in-situ” studies, these experiments provide an abundance of data. Viewing structural changes due to applied pressure conditions can give much-needed insight into materials performance. However, challenges exist for viewing/presenting results when the details are inherently three-dimensional (3D) in nature. For PZT perovskites, the use of polyhedra (e.g., Zr/Ti–O6 octahedra) to view bonding/connectivity is beneficial; however, the visualization of the octahedra behavior with pressure dependence is less easily demonstrated due to the complexity of the added pressure dimension. We present a more intuitive visualization by projecting structural data into virtual reality (VR). We employ previously published structural data for Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 as an exemplar for VR visualization of the PZT R3c crystal structure between ambient and 0.62 GPa pressure. This is accomplished via our in-house CAD2VR™ software platform and the new CrystalVR plugin. The use of the VR environment enables a more intuitive viewing experience, while enabling on-the-fly evaluation of crystal data, to form a detailed and comprehensive understanding of in-situ datasets. Discussion of methodology and tools for viewing are given, along with how recording results in video form can enable the viewing experience.
A new ternary intermetallic compound Al3GaCu9 was synthesized experimentally. A high-quality powder diffraction pattern of the compound was collected by an X-ray diffractometer, and its crystal structure was determined using the Rietveld refinement method. Results show that the compound has a cubic cell with the Al4Cu9 structure type (space group $P\bar{4}3m$ and Pearson symbol cP52). The lattice parameter a = 8.7132(3) Å, unit-cell volume V = 661.52 Å3, calculated density Dcalc = 7.26 g/cm3, and Z = 4. The residual factors converge to Rp = 2.96%, Rwp = 4.06%, and Rexp = 2.57%. The experimentally obtained reference intensity ratio value is 7.04.
Herein, a new method to synthesise epoxide-based sequence-controlled polymers via anionic ring-opening monomer addition, a form of anionic ring-opening polymerisation, is presented. This technique allows in combination with post-polymerisation modification (PPM) reactions for the successful preparation of modified mPEG-b-oligo(allyl glycidyl ether) featuring the incorporation of one repeating unit on average at a time. Due to the possible introduction of a vast variety of molecules to the polymeric system via PPM reactions, a multitude of advanced functional polymeric materials can be generated. This, in combination with the chain extension reactions, allows for the synthesis of well-controlled and programmable architectures with particular properties. The structure of the sequence-controlled polymer was confirmed via 1H NMR spectroscopy, size exclusion chromatography, attenuated total reflection Fourier-transform infrared spectroscopy, and differential scanning calorimetry.
Despite the growing interest in addiction research, which demonstrates the potential predictive role of adverse childhood experiences (ACEs), little is known about their impact on the psychological symptoms of craving.
Methods
After reviewing the relevant diagnostic criteria for addiction and comorbid mental disorders along with routinely collected clinical and service-use data, 208 outpatients were assessed on the study protocol. Following the recruitment phase, nominal and ordinal data were analyzed using nonparametric methods.
Results
Most of the outpatients reported ACEs (89.1%) and experienced cravings (73.4–95.7%). A positive association between ACEs and either intention and preplanning (r = .14, p < .05) or lack of control (r = .15; p < .05) of the craving behavior was found.
Conclusion
Craving behavior in addiction remains a subject of debate. Although correlation analyses showed significant associations between reported ACEs and measures of craving, they were relatively small.
Parkinson’s disease (PD) is an irreversible neurodegenerative disorder clinically manifesting in uncontrolled motor symptoms. There are two primary hallmark features of Parkinson’s disease—an irreversible loss of dopaminergic neurons of the substantia nigra pars compacta and formation of intracellular insoluble aggregates called Lewy bodies mostly composed of alpha-synuclein. Using a clinical improvements-first approach, we identified several clinical trials involving consumption of a specific diet or nutritional supplementation that improved motor and nonmotor functions. Here, we aimed to investigate if and how pyrroloquinoline quinone (PQQ) compound disrupts preformed alpha-synuclein deposits using SH-SY5Y cells, widely used Parkinson’s disease cellular model. SH-SY5Y neuroblastoma cells, incubated in presence of potassium chloride (KCl) to induce alpha-synuclein protein aggregation, were treated with PQQ for up to 48 hr. Resulting aggregates were examined and quantified using confocal microscopy. Overall, nutritional compound PQQ reduced the average number and overall size of intracellular cytoplasmic alpha-synuclein aggregates in a PD cellular model.
This paper proposes a methodology for architecting microstructures with extremal stiffness, yield, and buckling strength using topology optimisation. The optimised microstructures reveal an interesting transition from simple lattice-like structures for yield-dominated situations to hierarchical lattice structures for buckling-dominated situations. The transition from simple to hierarchical is governed by the relative yield strength of the constituent base material as well as the volume fraction. The overall performances of the optimised microstructures indicate that maximum strength is determined by the buckling strength at low-volume fractions and yield strength at higher-volume fractions, regardless of the base material’s relative yield strength. The non-normalised properties of the optimised microstructures show that higher base material Young’s modulus leads to both higher Young’s modulus and strength of the architected microstructures. Furthermore, the polynomial order of the maximum strength lines with respect to mass density obtained from the optimised microstructures reduces as base material relative yield strength decreases, reducing from 2.3 for buckling-dominated thermoplastic polyurethane to 1 for yield-dominated steel microstructures.
Mechanical metamaterials have attracted extensive attention. This paper reports a metamaterial with tunable elastic wave bandgaps based on bistable buckling structure. First, we find that deformation of two symmetric buckling shells is intrinsically asymmetric, which blocks the realisation of robust tunability. Based on an analytical model, we clarify that the mechanisms for this intrinsic asymmetricity are the bifurcations on force–deformation curves. Then we propose a superposition method of buckling shells, which can realise the symmetric deformation for robust tunable stiffness. Using this variable-stiffness oscillator, we design a metamaterial sandwich beam, and numerically and experimentally demonstrate its tunable bandgap for vibration suppression. This paper presents the unusual deformation process of buckling elements widely used for constructing metamaterials, and provides a robust way to realise metamaterials with tunable vibration bandgaps.
Artificial intelligence (AI) has advanced considerably, AlphaFold2 protein models are as good as X-ray results, language models like ChatGPT can pass MBA and medical exams, and deep learning models Midjourney, and Stable Diffusion can emulate artistic styles. Given current progress, could text-based inputs be used for the generative design of artificial proteins, pathways, or even organisms, with traits designed purely by AI? Existing strategies for biotechnology design are founded in knowledge-based approaches, such as rational enzyme engineering or whole pathway design using synthetic biology, often borrowing “parts” from other organisms. Alternatively, desired traits are achieved via random mutagenesis with iterative selection procedures. Both are costly in terms of acquiring knowledge and undertaking experimentation. Recently, advances in protein language models have allowed AI to implicitly “learn” properties that allow sequences to be folded alongside other embedded learning techniques for function prediction from primary sequences. Thus, AI offers varied routes to predicting biological outcomes from DNA sequences. However, AI has not yet been extensively used to design novel functions, despite the wealth of functionally annotated protein products at our fingertips. Thus, generative protein language models for biodesign represent a promising future. We seek to explore current technological limits and challenges, investigate new avenues and methodologies to make this possible and broach discussion around wider issues arising from AI-designed life.
As a major approach for controlling electromagnetic (EM) waves, metamaterials have experienced an abundant and rapid development in the 21st century. They have provided flexible and powerful techniques for controlling EM waves and brought many unique applications that are difficult to realise with natural materials. With increasing demands on dynamic controls of the EM waves, many innovations have been conducted in both three-dimensional metamaterials and two-dimensional metasurfaces, in which the meta-atom has been gradually evolved from passive to active. In 2014, coding and digital mechanisms were initially introduced to the metamaterials, further advancing the appearance of digitally programmable metamaterials. The programmable metamaterials have shown great potentials in not only real-time manipulations of the EM waves, but also direct information processing on the EM wave level. In this article, we present an in-depth review of the programmable EM metamaterials and metasurfaces, focusing on the programmable features including theoretical concepts, implementing methods and applications in EM controls. We first give a short retrospect of traditional metamaterials and metasurfaces, followed by the concepts and detailed discussions of digital coding and field-programmable metamaterials. Then, we introduce space-domain, time-domain and space–time-domain programmable metamaterials and metasurfaces, mainly focusing on their theories, functionalities, experimental implementations, and system-level applications. Finally, we conclude the current advances of the programmable metamaterials and metasurfaces, and give a prospect for the future developments.
X-ray powder diffraction data, including unit cell parameters and space group assignment, for the ESP15228 species of C19H34O5 formula, are here reported [a = 6.0434(6), b = 12.2543(6), c = 14.0285(8) Å, α = 86.584(3), β = 85.707(10), γ = 78.801(5)°, V = 1015.2(1) Å3, Z = 2, ρcalc = 1.152 g cm−3, and space group P-1]. All measured lines were indexed and no detectable impurities were observed.
The crystal structure of butenafine hydrochloride has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. Butenafine hydrochloride crystallizes in space group P21 (#4) with a = 13.94807(5), b = 9.10722(2), c = 16.46676(6) Å, β = 93.9663(5)°, V = 2086.733(8) Å3, and Z = 4. Butenafine hydrochloride occurs as a racemic co-crystal of R and S enantiomers of the cation. The crystal structure is characterized by parallel stacks of aromatic rings along the b-axis. Each cation forms a strong discrete N–H⋯Cl hydrogen bond. The chloride anions also act as acceptors in several C–H⋯Cl hydrogen bonds from methylene, methyl, and aromatic groups. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®).
In deception research, little consideration is given to how the framing of the question might impact the decision-making process used to reach a veracity judgment. People use terms such as “sure” to describe their uncertainty about an event (i.e., aleatory) and terms such as “chance” to describe their uncertainty about the world (i.e., epistemic). Presently, the effect of such uncertainty framing on veracity judgments was considered. By manipulating the veracity question wording the effect of uncertainty framing on deception detection was measured. The data show no difference in veracity judgments between the two uncertainty framing conditions, suggesting that these may operate on a robust and invariant cognitive process.
A theoretical and experimental framework for novel metamaterial with programmable damping properties is presented. This material system is able to switch between elastic-dominated and damping-dominated regimes with different overall stiffness under dynamic loading depending on the external stimulus. The unit cell combines an auxetic and a bellow-like layer separated by an interface through which the amount of media flow can be tuned depending on the lateral strain. A simplified analytical model is derived to analyse the programmable damping effect. The model is further extended with a fluid-dynamics approach to link the effective damping properties with geometrical parameters to aid with the practical design of the metamaterial. Afterward, experiments are conducted on a macroscopic level using laser-sintered unit cells to validate the functionality of the concept both with air and water as media within the unit cells. To conclude the work, initial results on microscopic-level unit cells fabricated by two-photon lithography are introduced to showcase the scalability of the concept. This work provides an experimentally validated theoretical framework for future investigations to design unit cells with programmable damping on different length scales for applications requiring tailored dynamic energy dissipation.
Shape memory polymers (SMPs) are atype of programmable materials capable of transforming their shapes in a pre-programmed way upon the application of an external stimulus. These materials have been tested for various potential applications particularly in the biomedical field for polymers with general and specific requirements. This review focuses on the recent advances in biomedical applications, including self-tightening sutures, pressure bandages, self-expansion stents, tissue engineering scaffolds, artificial muscles, drug delivery, and orthodontic archwires, after a brief description of the concepts, classifications, programming procedures, and material requirements of SMPs.