Complex Arrays Research Articles

Near-Surface 2D Imaging via FWI of DAS Data: An Examination on the Impacts of FWI Starting Model

Full waveform inversion (FWI) and distributed acoustic sensing (DAS) are powerful tools with potential to improve how seismic site characterization is performed. FWI is able to provide true 2D or 3D images of the subsurface by inverting stress wave recordings collected over a wide variety of scales. DAS can be used to efficiently collect high-resolution stress wave recordings from long and complex fiber optic arrays and is well-suited for large-scale site characterization projects. Due to the relative novelty of combining FWI and DAS, there is presently little published literature regarding the application of FWI to DAS data for near-surface (depths < 30 m) site characterization. We perform 2D FWI on DAS data collected at a well-characterized site using four different, site-specific 1D and 2D starting models. We discuss the unique benefits and challenges associated with inverting DAS data compared to traditional geophone data. We examine the impacts of using the various starting models on the final 2D subsurface images. We demonstrate that while the inversions performed using all four starting models are able to fit the major features of the DAS waveforms with similar misfit values, the final subsurface images can be quite different from one another at depths greater than about 10 m. As such, the best representation(s) of the subsurface are evaluated based on: (1) their agreement with borehole lithology logs that were not used in the development of the starting models, and (2) consistency at shallow depths between the final inverted images derived from multiple starting models. Our results demonstrate that FWI applied to DAS data has significant potential as a tool for near-surface site characterization while also emphasizing the significant impact that starting model selection can have on FWI results.

Interaction of [Er(HL)(L)]·4CHCl3·H2O Single-Ion Magnet Complexes with Ferromagnetic Microparticles

A new method is developed to control the spin relaxation in single-molecular magnets (SMMs) in order to eliminate spin decoherence to the level acceptable for quantum computing at a relaxation frequency of about 102 Hz and a temperature of 2 K. A significant part of the SMMs has rapid magnetic relaxation proceeding through several parallel channels sensitive to the presence of an external magnetic field. Some of the relaxation channels in such materials (also called single-ion magnets (SIMs)) are suppressed using an electromagnet in macroscopic volumes of complexes. This is unacceptable when individual SIM complexes are used as qubits and forces us to look for ways to use a local magnetic field and other types of complex interactions in a specially selected environment, which provides the Zeeman interaction in the absence of an external field. We demonstrate that a composite material made of SIM complexes with Er3+ ions and ferromagnetic microparticles exhibits a remanent magnetization, which is sufficient to decrease the spin relaxation frequency in the volume. In magnitude, this effect competes with the well-known effect of hybridization of the orbitals of a complex during its interaction with a metallic surface. Therefore, the microstructuring of an array of complexes in a ferromagnetic matrix can be used to create local regions with a controlled magnetic relaxation frequency

Super-resolved heterochromatin structure during DNA damage response revealed by CRISPR imaging.

Heterochromatin plays an important role in gene expression regulation and accurate chromosome segregation. Heterochromatin undergoes a DNA damage repair process distinct from that of euchromatin, involving large-scale rearrangement coupled to nuclear membrane and motor proteins. Revealing the nanoscale structure and dynamics of heterochromatin during its repair is essential for understanding the detailed mechanism of the wholeness DNA repair process, and the role of the distinct compaction and reorganization of heterochromatin. Here, we observed the novel structure and dynamics of heterochromatin in super resolution using CRISPR labeling techniques. Dense labeling of a pericentromeric region with CRISPR prevented cell cycle progression and induced DNA damage response accompanied by domain expansion and fiber-like extension beyond its chromosome territory. This structural change correlates with the DNA damage repair proteins. Due to persistent binding of an array of CRISPR complexes, the cell failed to repair the perceived damage, resulting in senescence-like phenotype. Use of advanced CRISPR labeling techniques allowed super-resolution imaging of the chromatin domain under repair in live cells. Our work highlights the DNA damage response in heterochromatin induced by molecular blockades and the resulting structural changes, providing a platform to study DNA repair process with high spatiotemporal resolution.

Emergent non-Hermitian localization phenomena in the synthetic space of zero-dimensional bosonic systems

Phase transitions in non-Hermitian systems are at the focus of cutting edge theoretical and experimental research. On the one hand, parity-time- $(\mathcal{PT}\ensuremath{-})$ and $\mathrm{anti}\ensuremath{-}\mathcal{PT}\ensuremath{-}\mathrm{symmetric}$ physics have gained ever-growing interest, due to the existence of non-Hermitian spectral singularities called exceptional points (EPs). On the other hand, topological and localization transitions in non-Hermitian systems reveal new phenomena, e.g., the non-Hermitian skin effect and the absence of conventional bulk-boundary correspondence. The great majority of previous studies exclusively focus on non-Hermitian Hamiltonians, whose realization requires an a priori fine-tuned extended lattice to exhibit topological and localization transition phenomena. In this work, we show how the non-Hermitian localization phenomena can naturally emerge in the synthetic field moment space of zero-dimensional bosonic systems, e.g., in $\mathrm{anti}\ensuremath{-}\mathcal{PT}$- and $\mathcal{PT}\ensuremath{-}\mathrm{symmetric}$ quantum dimers. This offers an opportunity to simulate localization transitions in low-dimensional systems, without the need to construct complex arrays of, e.g., coupled cavities or waveguides. Indeed, the field moment equations of motion can describe an equivalent (quasi)particle moving in a one-dimensional (1D) synthetic lattice. This synthetic field moment space can exhibit nontrivial localization phenomena, such as non-Hermitian skin effect, induced by the presence of highly degenerate EPs. We demonstrate our findings on the example of an $\mathrm{anti}\ensuremath{-}\mathcal{PT}\ensuremath{-}\mathrm{symmetric}$ two-mode system, whose higher-order field moment eigenspace is emulated by a synthetic 1D non-Hermitian Hamiltonian having a Sylvester matrix shape. Our results can be directly verified in state-of-the-art optical setups, such as superconducting circuits and toroidal resonators, by measuring photon moments or correlation functions.

High-Quality Artery Monitoring and Pathology Imaging Achieved by High-Performance Synchronous Electrical and Optical Output of Near-Infrared Organic Photodetector.

Near-infrared organic photodetectors (NIR-OPDs) are significant technologies in emerging biomedicine applications for uniquely wearable, noninvasive, low-cost advantages. However, biosignals are weak and changing rapidly so practical biodetection and bioimaging are still challenging for NIR-OPDs. Herein, high-performance NIR-OPDs with synchronous optical output are realized by recombining anode-injected electrons with photogenerated holes on emitters. Owing to high detection performance of 4.5× 1012 Jones detectivity and 120 kHz -3 dB bandwidth, five arteries are monitored by transmission-type method and cardiac cycle is analyzed. Importantly, the synchronous optical output is direct emission demonstrating outstanding photon conversion efficiency approaching 20% and luminance signal-to-noise ratio over 8000. Consequently, pathology imaging is directly developed without complex readout circuits and arrays from which squamous metaplasia of cervix and carcinoma of large intestine are observed clearly. The NIR-OPD demonstrates strategies for high-performance synchronous electrical/optical output and directly imaging. Biomedicine applications implemented here are high level, representing important steps for NIR-OPDs toward providing clues for clinical diagnosis.

Synthesis, spectral characterization, electrochemical studies of pesticide and biological evaluation of transition metal complexes of azo dye derived from substituted phenyl pyrazole

Diazotization of p-nitro aniline followed by coupling with 3-methyl-1-phenyl pyrazole to procure biologically active azo-dye ligand 3-methyl-4-[(E)-(4-nitrophenyl) diazenyl]-1-phenyl-1H-pyrazol-5-ol (NDP) and also the array of transition metal complexes of aforementioned azo-dye ligand has been carried off along with the use of metal complex to detect pesticides electrochemically. Structural verification of synthesized compounds was carried out via 1H and 13C NMR along with the percentage of C,H,N, molecular weights, Infra-red, UV-Visible spectra and molar conductance of ligand and its complexes was observed. Also TGA, P-XRD and CV measurements were noted. An antimicrobial potency was evaluated by well diffusion method and antioxidant efficacy by DPPH technique. Molecular docking studies was used and MTT tests were conducted on MCF-7 and Hela cell lines to investigate anticancer potency. Upon utilizing physical and spectroscopic techniques to characterize the novel azo-dye ligand and its transition coordinated compounds justified the bi-dentate nature of ligand. Further CV measurements showed that the synthesized Co(II) complex exhibited excellent electrocatalysis properties for the electrochemical sensing of pesticide(Ammonium salt of glyphosate 71% SG) with wider linear range of 0.1 μM–0.8 μM and detection limit 0.033 μM. Mn(II) and Co(II) complex displayed good anti-microbial activity along with cytotoxic potency whereas Co(II) and Cu(II) compounds indicated good anti-oxidant activity. Thus, NDP and its complexes being structurally supported via spectral data and CV studies affirms that Co(II) is strongly useful in detecting pesticide. And lastly it was found that all metal complexes have admirable bioefficacy when compared to ligand.

Analytical Assessment of Time-Varying Reliability and Penetration Limit of PV-Integrated Systems

This article presents a discrete convolution-based method for reliability evaluation of a grid-connected photovoltaic (PV) system, where special consideration is given to the variable availability of PV array components. Along with the negative impacts of variable solar irradiance and ambient temperature on the PV power generation, they affect the reliability of PV system power electronic components. A variable availability model based on the power loss in the semiconductors of PV system components is needed to account for this effect in the reliability analysis. The article proposes a 3-D capacity outage model of a PV farm that accounts for the variable availability and the redundancies associated with the topologically complex multistring PV arrays. The outage model is used to construct a PV capacity outage probability and frequency table (COPAFT), which along with conventional generation COPAFT, is convolved with the distribution of load to determine system reliability. An integration limit assessment tool is also developed within the proposed framework, ensuring that the PV power integration does not violate the system frequency stability. Simulations on the modified IEEE RTS-79 system demonstrate the efficacy of the proposed method.

Semirigid Ligands Enhance Different Coordination Behavior of Nd and Dy Relevant to Their Separation and Recovery in a Non-aqueous Environment.

Rare-earth elements are widely used in high-end technologies, the production of permanent magnets (PMs) being one of the sectors with the greatest current demand and likely greater future demand. The combination of Nd and Dy in NdFeB PMs enhances their magnetic properties but makes their recycling more challenging. Due to the similar chemical properties of Nd and Dy, their separation is expensive and currently limited to the small scale. It is therefore crucially important to devise efficient and selective methods that can recover and then reuse those critical metals. To address these issues, a series of heptadentate Trensal-based ligands were used for the complexation of Dy3+ and Nd3+ ions, with the goal of indicating the role of coordination and solubility equilibria in the selective precipitation of Ln3+–metal complexes from multimetal non-water solutions. Specifically, for a 1:1 Nd/Dy mixture, a selective and fast precipitation of the Dy complex occurred in acetone with the Trensalp-OMe ligand at room temperature, with a concomitant enrichment of Nd in the solution phase. In acetone, complexes of Nd and Dy with Trensalp-OMe were characterized by very similar formation constants of 7.0(2) and 7.3(2), respectively. From the structural analysis of an array of Dy and Nd complexes with TrensalR ligands, we showed that Dy invariably provided complexes with coordination number (cn) of 7, whereas the larger Nd experienced an expansion of the coordination sphere by recruiting additional solvent molecules and giving a cn of >7. The significant structural differences have been identified as the main premises upon which a suitable separation strategy can be devised with these kind of ligands, as well as other preorganized polydentate ligands that can exploit the small differences in Ln3+ coordination requirements.

Reducing circuit complexity in optical quantum computation using 3D architectures.

Integrated photonic architectures based on optical waveguides are one of the leading candidates for the future realisation of large-scale quantum computation. One of the central challenges in realising this goal is simultaneously minimising loss whilst maximising interferometric visibility within waveguide circuits. One approach is to reduce circuit complexity and depth. A major constraint in most planar waveguide systems is that beamsplitter transformations between distant optical modes require numerous intermediate SWAP operations to couple them into nearest neighbour proximity, each of which introduces loss and scattering. Here, we propose a 3D architecture which can significantly mitigate this problem by geometrically bypassing trivial intermediate operations. We demonstrate the viability of this concept by considering a worst-case 2D scenario, where we interfere the two most distant optical modes in a planar structure. Using femtosecond laser direct-writing technology we experimentally construct a 2D architecture to implement Hong-Ou-Mandel interference between its most distant modes, and a 3D one with corresponding physical dimensions, demonstrating significant improvement in both fidelity and efficiency in the latter case. In addition to improving fidelity and efficiency of individual non-adjacent beamsplitter operations, this approach provides an avenue for reducing the optical depth of circuits comprising complex arrays of beamsplitter operations.

Active genetics comes alive: Exploring the broad applications of CRISPR-based selfish genetic elements (or gene-drives): Exploring the broad applications of CRISPR-based selfish genetic elements (or gene-drives).

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based "active genetic" elements developed in 2015 bypassed the fundamental rules of traditional genetics. Inherited in a super-Mendelian fashion, such selfish genetic entities offered a variety of potential applications including: gene-drives to disseminate gene cassettes carrying desired traits throughout insect populations to control disease vectors or pest species, allelic drives biasing inheritance of preferred allelic variants, neutralizing genetic elements to delete and replace or to halt the spread of gene-drives, split-drives with the core constituent Cas9 endonuclease and guide RNA (gRNA) components inserted at separate genomic locations to accelerate assembly of complex arrays of genetic traits or to gain genetic entry into novel organisms (vertebrates, plants, bacteria), and interhomolog based copying systems in somatic cells to develop tools for treating inherited or infectious diseases. Here, we summarize the substantial advances that have been made on all of these fronts and look forward to the next phase of this rapidly expanding and impactful field.

Rigid α-diimine palladium complexes as direct C-H arylation precatalysts for thiophenes and heteroaryl bromides

• An array of rigid α-diimine palladium complexes were reported. • These palladium complexes efficiently promoted the direct C-H arylation under mild reaction conditions. • Cross-coupling of a variety of thiophene with heteroaryl bromides afforded excellent yields and high reigioselectivity. The direct C-H heteroarylation of thiophenes, promoted by rigid α-diimine palladium complexes is described. This approach exhibits broad substrate scopes with functional group tolerant, and proceeds with the formation of regioselective products.

EEG Responses to auditory figure-ground perception

Speech-in-noise difficulty is commonly reported among hearing-impaired individuals. Recent work has established generic behavioural measures of sound segregation and grouping that are related to speech-in-noise processing but do not require language. In this study, we assessed potential clinical electroencephalographic (EEG) measures of central auditory grouping (stochastic figure-ground test) and speech-in-noise perception (speech-in-babble test) with and without relevant tasks. Auditory targets were presented within background noise (16 talker-babble or randomly generated pure-tones) in 50% of the trials and composed either a figure (pure-tone frequency chords repeating over time) or speech (English names), while the rest of the trials only had background noise. EEG was recorded while participants were presented with the target stimuli (figure or speech) under different attentional states (relevant task or visual-distractor task). EEG time-domain analysis demonstrated enhanced negative responses during detection of both types of auditory targets within the time window 150-350 ms but only figure detection produced significantly enhanced responses under the distracted condition. Further single-channel analysis showed that simple vertex-to-mastoid acquisition defines a very similar response to more complex arrays based on multiple channels. Evoked-potentials to the generic figure-ground task therefore represent a potential clinical measure of grouping relevant to real-world listening that can be assessed irrespective of language knowledge and expertise even without a relevant task.

Improving brain B0 shimming using an easy and accessible multi-coil shim array at ultra-high field

ObjectImprove shimming capabilities of ultra-high field systems, with addition of an accessible low-complexity B0 shim array for head MRI at 7 T.Materials and methodsAn eight channel B0 shim coil array was designed as a tradeoff between shimming improvement and construction complexity, to provide an easy to use shim array that can be employed with the standard 7 T head coil. The array was interfaced using an open-source eight-channel shim amplifier rack. Improvements in field homogeneity for whole-brain and slice-based shimming were compared to standard second-order shimming, and to more complex higher order dynamic shimming and shim arrays with 32 and 48 channels.ResultsThe eight-channel shim array provided 12% improvement in whole brain static shimming and provided 33% improvement when using slice-based shimming. With this, the eight-channel array performed similar to third-order dynamic shimming (without the need for higher order eddy current compensation). More complex shim arrays with 32 and 48 channels performed better, but require a dedicated RF coil.DiscussionThe designed eight-channel shim array provides a low-complexity and low-cost approach for improving B0 field shimming on an ultra-high field system. In both static and dynamic shimming, it provides improved B0 homogeneity over standard shimming.

Detection and discrimination of antibiotics in food samples using a microfluidic paper-based optical tongue.

Antibiotics are used largely in agriculture and animal farming. As a result, antibiotic residues are found in food products as well as pharmaceutical industries and farming wastes. Since consumption of food products contaminated with antibiotic in excessive residuals causes severe environmental risks, our study here aims to detect the residues level of selected antibiotics in milk and egg. For monitoring of the antibiotic residues in various food diaries, low-cost, simple and rapid methods are required. This paper reports fabricating a disposable microfluidic paper-based analytical device for detection and discrimination of 8 antibiotics. This small but efficient device works based on combination of paper microfluidics, sensor array concept (an array of metallochromic complexes, which provides an optical tongue, and chemometrics data analysis. The discrimination is based on differential interaction of the antibiotics with 5 metal-indicator complexes and displacing the chromogenic indicators. This resulted in specific color changes for each antibiotic. The discriminant models obtained by employing linear discriminant analysis could discriminate antibiotics in real samples of milk and egg white and yolk at concentrations of as low as 5.0mgL-1 with 100% accuracy. Also, semi-quantitative analysis was provided to detect trace amounts of the antibiotics (1.0mgL-1).

Co-phase state detection for segmented mirrors by dual-wavelength optical vortex phase-shifting interferometry.

The application of large-aperture telescopes requires the support of co-phase measurement techniques for segmented mirrors. This paper proposes a novel method to detect the co-phase state of segmented mirrors by applying a dual-wavelength phase-shifting interferometer based on optical vortex. Theory and experiments indicate that the wrapped phase map edges obtained by phase-shifting interference of the vortex beam are distributed in the form of a Fermat spiral. The piston error of the segmented mirrors corresponds to the rotation of the standard Fermat spiral center. In contrast, the tip/tilt error corresponds to the alteration of the center position of the deformed Fermat spiral. The rotation angle and the center position of the spiral are obtained by curve fitting, and the co-phase errors can be inversely solved. The experiments achieved an accuracy of approximately 4.04 nm in the piston and 0.16″ in the tip/tilt. The method avoids using complex lens arrays and devices, has an extended measurement range, high accuracy, and allows the co-phase errors between all sub-mirrors to be obtained in real-time. This study provides a novel and general method for detecting co-phase errors in a segmented primary mirror.

Predictive Biophysical Cue Mapping for Direct Cell Reprogramming Using Combinatorial Nanoarrays.

Biophysical cues, such as nanotopographies of extracellular matrix (ECM), are key cell regulators for direct cell reprogramming. Therefore, high-throughput methods capable of systematically screening a wide range of biophysical cue-regulated cell reprogramming are increasingly needed for tissue engineering and regenerative medicine. Here, we report the development of a dynamic laser interference lithography (DIL) to generate large-scale combinatorial biophysical cue (CBC) arrays with diverse micro/nanostructures at higher complexities than most current arrays. Using CBC arrays, a high-throughput cell mapping method is further demonstrated for the systematic investigation of biophysical cue-mediated direct cell reprogramming. This CBC array-based high-throughput cell screening approach facilitates the rapid identification of unconventional hierarchical nanopatterns that induce the direct reprogramming of human fibroblasts into neurons through epigenetic modulation mechanisms. In this way, we successfully demonstrate DIL for generating highly complex CBC arrays and establish CBC array-based cell screening as a valuable strategy for systematically investigating the role of biophysical cues in cell reprogramming.

The Fowler–Nordheim plot behaviour from virtual field emitters arrays of zinc oxide nanorods mixed with carbon nanotubes

ABSTRACT The Fowler–Nordheim plot behaviour is investigated for large area field emitters arrays composed of mixtures of ZnO nanorods and single-wall carbon nanotubes (CNTs). The field emission current–voltage characteristics are calculated using the Murphy-Good equation based on the Fowler–Nordheim model. The influencing factors taken into consideration are the radii of the ZnO rods, the heights of the CNTs, the variation of the onset voltage of the saturation of the ZnO conduction band (CB) emission current and the degradation of the CNTs at high applied voltages. The results show that the FN plots of the mixed arrays exhibit nonlinear behaviour near the high-field region which could be related to the FN plot behaviour of the constituting emitters arrays. The distribution of the emitters geometrical parameters and the onset of saturation of the ZnO CB current are found to affect the FN plot behaviour of the pure ZnO, CNTs arrays as well as mixed arrays. The comparisons between the FN plots from the present work and those measured experimentally are found useful to shed light on the field emission mechanism. This may in turn aid the development of complex field emission arrays for future technological applications. The work also shows the possibility to apply the standard FN model to complex large area field emitters arrays.

Microtubules as Regulators of Neural Network Shape and Function: Focus on Excitability, Plasticity and Memory.

Neuronal microtubules (MTs) are complex cytoskeletal protein arrays that undergo activity-dependent changes in their structure and function as a response to physiological demands throughout the lifespan of neurons. Many factors shape the allostatic dynamics of MTs and tubulin dimers in the cytosolic microenvironment, such as protein–protein interactions and activity-dependent shifts in these interactions that are responsible for their plastic capabilities. Recently, several findings have reinforced the role of MTs in behavioral and cognitive processes in normal and pathological conditions. In this review, we summarize the bidirectional relationships between MTs dynamics, neuronal processes, and brain and behavioral states. The outcomes of manipulating the dynamicity of MTs by genetic or pharmacological approaches on neuronal morphology, intrinsic and synaptic excitability, the state of the network, and behaviors are heterogeneous. We discuss the critical position of MTs as responders and adaptative elements of basic neuronal function whose impact on brain function is not fully understood, and we highlight the dilemma of artificially modulating MT dynamics for therapeutic purposes.

Effect of fermented fish tonic on the growth and yield of Glycine max. (L)

Fermented fish tonic (FFT) help to provide complex arrays of macro and micro nutrients and minerals. The present study was conducted to find out the effect of Fermented fish tonic on the growth and yield of Glycine max. (L) .The experimental design was Completely Randomized Design (CRD). Five treatments were defined with five replications viz. T1: Distilled water (Control), T2: 10, T3: 20, T4: 50 and T5: 100%. FFT. All the other management practices were followed uniformly. Growth and yield parameters were measured and analysed statistically using ANOVA test and means were compared with DMRT. Results proved that, application of 20% FFT significantly increased the plant height (9.6%), chlorophyll content (23.02%), number of leaves (43.66%), leaf area (65%), number of nodules (74.35%), and the total yield (75.28%) compared to the control plants. Therefore, this experiment concluds that application of 20% FFT increases the growth and yield on Glycine max. (L)

The Chosen Few: Parallel Library Reaction Methodologies for Drug Discovery.

Parallel library synthesis is an important tool for drug discovery because it enables the synthesis of closely related analogues in parallel via robust and general synthetic transformations. In this perspective, we analyzed the synthetic methodologies used in >5000 parallel libraries representing 15 prevalent synthetic transformations. The library data set contains complex substrates and diverse arrays of building blocks used over the last 14 years at AbbVie. The library synthetic methodologies that have demonstrated robustness and generality with proven success are described along with their substrate scopes. The evolution of the synthetic methodologies for library synthesis over the past decade is discussed. We also highlight that the combination of parallel library synthesis with high-throughput experimentation will continue to facilitate the discovery of library-amenable synthetic methodologies in drug discovery.