Electron Microscopy Data Research Articles

Synthesis of Carbon and Gold Nanoparticles in Ionic Liquid Crystals: Structural Properties and Electrical Behavior for Electro‐Optical Sensors

ABSTRACTThe structural and electrical properties of ionic metal‐alkanoate nanocomposites obtained based on a cadmium octanoate matrix with individual carbon and gold nanoparticles (NPs) as well as their combination are studied. Carbon and gold NPs were chemically synthesized within the smectic A phase of Cd+2(C7H15COO−)2, which served as a well‐ordered nanoreactor. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) data provide information on NPs location and allow the estimation of the sizes of the synthesized NPs inside the glassy liquid crystalline matrix. It is shown that the size and shape of the NPs were precisely controlled during synthesis, resulting in highly stable and organized nanocomposites. The electrical characteristics were studied in a wide temperature range corresponding to different phase states of the nanocomposites. We compared the electrical properties of both pure matrix and nanocomposites with carbon and gold NPs to identify the potential of the nanocomposite materials for designing new sensor structures. Notably, the nanocomposites exhibited anisotropic conductivity, highlighting the structural anisotropy of the material. In addition, using NPs allows fine‐tuning of the electrical properties of a metal‐alkanoate host matrix. The obtained nanocomposites open prospects for the development of electro‐optical sensors with high sensitivity and specificity that can be used to detect a variety of chemical and physical parameters including temperature, composition of substances, and environment.

Effect of growth dynamics on the structural, photophysical and pseudocapacitance properties of famatinite copper antimony sulphide colloidal nanostructures (including nanosheets).

Facile phase selective synthesis of copper antimony sulphide (CAS) nanostructures is important because of their tunable photoconductive and electrochemical properties. In this study, off-stoichiometric famatinite phase CAS (fCAS) quasi-spherical and quasi-hexagonal colloidal nanostructures (including nanosheets) of sizes, 2.4-18.0 nm were grown under variable conditions of temperature (60-200 °C), time and oleylamine capping ligand concentration using copper(II) acetylacetonate and antimony(III) diethyldithiocarbamate precursors. Data from powder X-ray diffraction, Raman spectroscopy and high-resolution scanning/transmission electron microscopy confirm the tetragonal structure of the famatinite phase. X-ray photoelectron spectroscopy, transmission electron microscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy data suggest a correlation of particle size, morphology and composition of the off-stoichiometric fCAS nanostructures with growth temperature and time, and oleylamine concentration. The off-stoichiometric Cu3-aSb1+bS4±c (a, b, c - mole fractions) nanostructures being severely copper-deficient and antimony-rich, exhibit shallow-lying acceptor copper vacancy states, deep-lying donor states of antimony interstitials, sulphur vacancies and antimony-copper antisites and shallow-lying acceptor surface trapping states. These electronic states are likely implicated in tunable UV-visible absorption and bandgaps between 2.3 and 2.8 eV, and broad visible-NIR photoluminescence with fast recombination of radiative lifetimes between 0.2 and 6.2 ns, confirmed from absorption, steady-state and time-resolved photoluminescence spectroscopies. Additionally, cyclic voltammetry and electrochemical impedance spectroscopy confirm that electrodes of the fCAS nanostructures display slightly variable pseudocapacitance of charge-storage primarily via possible sodium ion intercalation with a high specific capacitance of ∼84 F g-1 obtained at a scan rate of 5 mV s-1. Overall, these results show the influence of composition, in particular point defects, phase quality and morphology on the optical and pseudocapacitance properties of fCAS nanostructures, suitable as solar absorbers or electrodes for energy storage devices.

Physics-Based Synthetic Data Model for Automated Segmentation in Catalysis Microscopy.

In catalysis research, the amount of microscopy data acquired when imaging dynamic processes is often too much for nonautomated quantitative analysis. Developing machine learned segmentation models is challenged by the requirement of high-quality annotated training data. We thus substitute expert-annotated data with a physics-based sequential synthetic data model. We study environmental scanning electron microscopy (ESEM) data collected from isopropanol oxidation to acetone over cobalt oxide as an example. Upon applying a temperature program during the reaction a phase transition occurs, reducing the catalyst selectivity toward acetone. This is accompanied on the micrometer ESEM scale by the formation of cracks between the pores of the catalyst surface. We aim to generate synthetic data to train a neural network capable of semantic segmentation (pixel-wise labeling) of this ESEM data. This analysis will lead to insights into this phase transition. To generate synthetic data that approximates this transition, our algorithm composes the ESEM images of the room-temperature catalyst with dynamically evolving synthetic cracks satisfying physical construction principles, gathered from qualitative knowledge accessible in the ESEM data. We mimic the surface crack growth propagation along surface paths, avoiding close vicinity to nearby pores. This physics-based approach results in a lowered rate of false positives compared to a random approach.

New nucleolin-containing cytoplasmic bodies in an archamoebian protist Pelomyxa belevskii (Amoebozoa, Archamoebae, Pelobiontida).

The representatives of the archamoebian genus Pelomyxa are amoeboid anaerobic protists that inhabit fresh-water anoxic sediments, and most of them are usually multinucleate. The cytoplasm of these unicellular organisms is highly complicated and contains numerous vacuoles of different types, as well as a wide range of prokaryotic endocytobionts, agglomerations of glycogen, lipids, etc. Among the great variety of cytoplasmic structures in P.belevskii, we identified novel organelles termed Cytoplasmic Nucleolin-Rich Bodies (CNRBs) due to their enrichment in nucleolin, a nuclear/nucleolar protein. The P. belevskiiCNRBs differ significantly from known cytoplasmic nucleolin-related organelles encountered in some other eukaryotic cells, but their biological significance remains elusive. The work also provides the first description of the nuclear organization of P. belevskii. The nucleolar apparatus of P. belevskii contains little nucleolin, as determined by quantitative electron microscopic data, suggesting that it is inactive despite its morphological complexity. The presence of CNRBsin Pelomyxa is discussed in the context of the specific habitat conditions and biology of these unicellular eukaryotes.

Effects of Doping on Elastic Strain in Crystalline Ge-Sb-Te.

Phase-change random access memory (PcRAM) faces significant challenges due to the inherent instability of amorphous Ge2Sb2Te5 (GST). While doping has emerged as an effective method for amorphous stabilization, understanding the precise mechanisms of structural modification and their impact on material stability remains a critical challenge. This study provides a comprehensive investigation of elastic strain and stress in crystalline lattices induced by various dopants (C, N, and Al) through systematic measurements of film thickness changes during crystallization. Through detailed analysis of cross-sectional electron microscopy data and theoretical calculations, we reveal distinct behavior patterns between interstitial and substitutional dopants. Interstitial dopants (C and N) generate substantial elastic strain energy (~9 J/g) due to their smaller atomic radii (0.07-0.08 nm) and ability to occupy spaces between lattice sites. In contrast, substitutional dopants (Al) produce lower strain energy (~5 J/g) due to their similar atomic radius (0.14 nm) to host atoms. We demonstrate that N doping achieves higher elastic strain energy compared to C doping, attributed to its preferential formation of Ge-N bonds and resulting lattice distortions. The correlation between dopant properties, structural features, and induced strain energy provides quantitative insights for optimizing dopant selection. These findings establish a fundamental framework for understanding dopant-induced thermodynamic stabilization in GST materials, offering practical guidelines for enhancing the reliability and performance of next-generation PcRAM devices.

Nucleation and growth of zinc-templated mesoporous selenium nanoparticles and potential non-thermal effects during their microwave-assisted synthesis

The effects of 5.8-GHz microwave (MW) irradiation on the synthesis of mesoporous selenium nanoparticles (mSeNPs) in aqueous medium by reduction of selenite ions with ascorbic acid, using zinc nanoparticles as a hard template and cetyltrimethylammonium bromide (CTAB) as a micellar template, are examined for the first time with a particular emphasis on MW-particle interactions and the NPs morphology. This MW-assisted synthesis is compared to 2.45 GHz MW heating method and conventional hydrothermal method at around 100 °C to produce the nanoparticles of different morphology and particle size distributions. The NPs morphology is tailored by varying the temperature ramp characteristics and the MW irradiation time. Under mild synthesis conditions only spherical particles are formed. Enhancing temperature ramp rate in the presence of CTAB micelles increases the metal–semiconductor hybrid particles growth rate and promotes the formation of nanorods and branched shapes. The effect is MW frequency dependent and non-thermal to some extent. Multi-step mechanism of mSeNPs formation is proposed based on derivative UV–Vis spectrophotometry and scanning electron microscopy (SEM) data. Both the stability of the chemical composition at a single particle level and the high efficiency of zinc template removal are determined by single particle microwave plasma optical emission spectrometry (SP-MWP-OES). After Zn template removal mSeNPs can be loaded with antifungal carbamate agent, hence the application as a nanopesticide is suggested.

In-silico and In-vitro Evaluation of Novel Carboxamide Analogue on the Metastasis of Triple Negative Breast Cancer Cells Utilizing Novel PCPTC-loaded PEGylated-PLGA Nanocarriers.

This study aimed to determine the effects of novel N-{3-[(pyridin-4-yl)carbamoyl] phenyl} thiophene-2-carboxamide or PCPTC chemical moiety loaded Poly(lactic-co-glycolic acid)-Poly (Ethylene glycol) or (PLGA-PEGylated) NP as an anti-metastatic Ran GTPase therapeutic agent on MDA-MB231 triple-negative human breast cancer cells. Molecular docking and MD simulation was done to determine the binding potential of novel carboxamide PCPTC with Ran GTPase. PLGA and PLGA-PEG based NP encapsulating PCPTC were fabricated using the Modified Double Emulsion Solvent Evaporation Technique and characterized for size, zeta potential, polydispersity and morphology. In vitro evaluation of loaded nanoparticles such as cellular localization study, cell proliferation, cell migration, cell invasion and Ran Pull Down assay were carried out on MDA-MB231 breast cancer cells. Ran downregulation was determined by pull down assay. PCPTC with Ran GTPase exhibited strong structural stability based on in silico analysis. The average sizes of PCPTC loaded NP ranged between 166.3nm to 257.5nm and were all negatively charged. Scanning electron microscopy data showed that loaded NP were smooth and spherical. Fluorescence microscopy data confirmed the intracellular localization of loaded nanoparticles inside the MDA-MB231 cells. Cell proliferation assay (MTT assay) confirmed the cytotoxic effect of the loaded-NP when compared to blank nanoparticles. PCPTC-loaded NP inhibited metastasis and invasion of MDA-MB231 cells. This anti-metastatic and the anti-invasive effect was due to the Ran GTPase cycle blockage, which was confirmed by performing Ran Pull down assay. we propose that PCPTC is a promising compound to inhibit Ran GTPase and may act as a potential therapeutic agent against breast cancer. PCPTC-loaded NP successfully stopped the metastasis of MDA-MB231 cells by disrupting the Ran cycle.

Remote Ischemic Post-Conditioning (RIC) Mediates Anti-Inflammatory Signaling via Myeloid AMPKα1 in Murine Traumatic Optic Neuropathy (TON).

Traumatic optic neuropathy (TON) has been regarded a vision-threatening condition caused by either ocular or blunt/penetrating head trauma, which is characterized by direct or indirect TON. Injury happens during sports, vehicle accidents and mainly in military war and combat exposure. Earlier, we have demonstrated that remote ischemic post-conditioning (RIC) therapy is protective in TON, and here we report that AMPKα1 activation is crucial. AMPKα1 is the catalytic subunit of the heterotrimeric enzyme AMPK, the master regulator of cellular energetics and metabolism. The α1 isoform predominates in immune cells including macrophages (Mφs). Myeloid-specific AMPKα1 KO mice were generated by crossing AMPKα1Flox/Flox and LysMcre to carry out the study. We induced TON in mice by using a controlled impact system. Mice (mixed sex) were randomized in six experimental groups for Sham (mock); Sham (RIC); AMPKα1F/F (TON); AMPKα1F/F (TON+RIC); AMPKα1F/F LysMCre (TON); AMPKα1F/F LysMCre (TON+RIC). RIC therapy was given every day (5-7 days following TON). Data were generated by using Western blotting (pAMPKα1, ICAM1, Brn3 and GAP43), immunofluorescence (pAMPKα1, cd11b, TMEM119 and ICAM1), flow cytometry (CD11b, F4/80, CD68, CD206, IL-10 and LY6G), ELISA (TNF-α and IL-10) and transmission electron microscopy (TEM, for demyelination and axonal degeneration), and retinal oxygenation was measured by a Unisense sensor system. First, we observed retinal morphology with funduscopic images and found TON has vascular inflammation. H&E staining data suggested that TON increased retinal inflammation and RIC attenuates retinal ganglion cell death. Immunofluorescence and Western blot data showed increased microglial activation and decreased retinal ganglion cell (RGCs) marker Brn3 and axonal regeneration marker GAP43 expression in the TON [AMPKα1F/F] vs. Sham group, but TON+RIC [AMPKα1F/F] attenuated the expression level of these markers. Interestingly, higher microglia activation was observed in the myeloid AMPKα1F/F KO group following TON, and RIC therapy did not attenuate microglial expression. Flow cytometry, ELISA and retinal tissue oxygen data revealed that RIC therapy significantly reduced the pro-inflammatory signaling markers, increased anti-inflammatory macrophage polarization and improved oxygen level in the TON+RIC [AMPKα1F/F] group; however, RIC therapy did not reduce inflammatory signaling activation in the myeloid AMPKα1 KO mice. The transmission electron microscopy (TEM) data of the optic nerve showed increased demyelination and axonal degeneration in the TON [AMPKα1F/F] group, and RIC improved the myelination process in TON [AMPKα1F/F], but RIC had no significant effect in the AMPKα1 KO mice. The myeloid AMPKα1c deletion attenuated RIC induced anti-inflammatory macrophage polarization, and that suggests a molecular link between RIC and immune activation. Overall, these data suggest that RIC therapy provided protection against inflammation and neurodegeneration via myeloid AMPKα1 activation, but the deletion of myeloid AMPKα1 is not protective in TON. Further investigation of RIC and AMPKα1 signaling is warranted in TON.

Synthesis and Characterization of Hydroxyapatite Assisted by Microwave-Ultrasound from Eggshells for Use as a Carrier of Forchlorfenuron and In Silico and In Vitro Evaluation

This study utilized eggshell biomass as a calcium precursor for synthesizing hydroxyapatite (Hap) through a co-precipitation method assisted by a combined microwave-ultrasound (Mu/Us) crystallization process. Different milling techniques (mortar, high-energy mill, and sieving) were employed to prepare the eggshell biomass and identify the most effective calcium precursor. The precursor derived from high-energy milling, followed by sieving and thermal treatment at 750 °C (designated as Sample Hap-H3 750), was selected due to its higher porosity, enhanced crystallinity, and smaller particle size than other synthesized materials. This sample was subsequently used as a carrier for the plant hormone forchlorfenuron (FCF), forming the composite Hap-FCF. Comprehensive characterization was conducted using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), specific surface area analysis (BET method), zeta potential (ZP), scanning electron microscopy (SEM), and bright-field transmission electron microscopy (BFTEM), ensuring reliable and robust data. The in silico evaluation of the phytohormone FCF with two receptors, gibberellin (GA3Ox2) and auxin (IAA7), produced notable results. Docking and molecular dynamics (MD) simulations demonstrated that the gibberellin receptor was preferentially stimulated, as shown by the higher binding affinity and the receptor’s sustained stability during the MD simulations. These findings underscore the potential applications of this research, emphasizing its significance in materials science and biochemistry. Moreover, the in vitro assessment of Hap-H3 750, Hap-FCF, FCF, and the control (distilled water) on the germination and growth of butterhead lettuce seeds (Lactuca sativa) over 30 days revealed that Hap-H3 750 and Hap-FCF promoted plant growth by 275–330% relative to the control. This effect was attributed to the preferential stimulation of the gibberellin receptors responsible for stem and root elongation. These results suggest that HAP nanoparticles could facilitate the controlled delivery of FCF in the agricultural sector, promising to be an effective nanofertilizer.

Integrative Molecular Dynamics Simulations Untangle Cross‐Linking Data to Unveil Mitochondrial Protein Distributions

Cross‐linking mass spectrometry (XL‐MS) enables the mapping of protein‐protein interactions on the cellular level. When applied to all compartments of mitochondria, the sheer number of cross‐links and connections can be overwhelming, rendering simple cluster analyses convoluted and uninformative. To address this limitation, we integrate the XL‐MS data, 3D electron microscopy data, and localization annotations with a supra coarse‐grained molecular dynamics simulation to sort all data, making clusters more accessible and interpretable. In the context of mitochondria, this method, through a total of 6.9 milliseconds of simulations, successfully identifies known, suggests unknown protein clusters, and reveals the distribution of inner mitochondrial membrane proteins allowing a more precise localization within compartments. Our integrative approach suggests, that two so‐far ambigiously placed proteins FAM162A and TMEM126A are localized in the cristae, which is validated through super resolution microscopy. Together, this demonstrates the strong potential of the presented approach.

Integrative Molecular Dynamics Simulations Untangle Cross-Linking Data to Unveil Mitochondrial Protein Distributions.

Cross-linking mass spectrometry (XL-MS) enables the mapping of protein-protein interactions on the cellular level. When applied to all compartments of mitochondria, the sheer number of cross-links and connections can be overwhelming, rendering simple cluster analyses convoluted and uninformative. To address this limitation, we integrate the XL-MS data, 3D electron microscopy data, and localization annotations with a supra coarse-grained molecular dynamics simulation to sort all data, making clusters more accessible and interpretable. In the context of mitochondria, this method, through a total of 6.9 milliseconds of simulations, successfully identifies known, suggests unknown protein clusters, and reveals the distribution of inner mitochondrial membrane proteins allowing a more precise localization within compartments. Our integrative approach suggests, that two so-far ambigiously placed proteins FAM162A and TMEM126A are localized in the cristae, which is validated through super resolution microscopy. Together, this demonstrates the strong potential of the presented approach.

High-Speed Imaging-Based Particle Attribute Analysis of Spray-Dried Amorphous Solid Dispersions Using a Convolution Neural Network.

Spray drying is a well-established method for preparing amorphous solid dispersion (ASD) formulations to improve the oral bioavailability of poorly soluble drugs. In addition to the characterization of the amorphous phase, particle attributes of spray-dried intermediates (SDIs), including particle size, morphology, and microstructure, need to be carefully studied and controlled for optimizing drug product performance. Although recent developments in microscopy technology have enabled the analysis of morphological attributes for individual SDI particles, a high-throughput method is highly desirable. In this work, a fingerprinting method exploiting high-speed dynamic imaging, laser diffraction (LD), and a convolutional neural network (CNN) was developed to characterize and quantify size and morphological distributions of particles in batches of spray-dried ASDs. This imaging technology enables the generation of hundreds of thousands of single-particle images in a few minutes that are analyzed by both unsupervised and supervised CNN models. The unsupervised data mining analysis demonstrated that a batch of SDI is a mixture of diverse particle subpopulations with varying sizes and morphological attributes. Motivated by this observation, we developed a CNN model that enabled rapid computation of the volumetric composition of the distinct particle subpopulations in a SDI batch, thus generating a morphological fingerprint. We implemented this high-speed imaging-based particle attribute analysis method to investigate SDIs containing hypromellose acetate succinate as a model system. The CNN fingerprint results enabled quantification of the changes in the morphological distribution of SDI batches prepared with variations in the spray drying process parameters, and the results were in line with the LD and electron microscopy data. Our experiments and analysis demonstrate the robustness and throughput of this fingerprinting approach for quantifying particle size and morphological distributions of individual SDI batches, which can help guide spray drying process development and thereby enable the development of a drug product with more robust process and optimized performance.

A connectome manipulation framework for the systematic and reproducible study of structure–function relationships through simulations

Abstract Synaptic connectivity at the neuronal level is characterized by highly non-random features. Hypotheses about their role can be developed by correlating structural metrics to functional features. But to prove causation, manipulations of connectivity would have to be studied. However, the fine-grained scale at which non-random trends are expressed makes this approach challenging to pursue experimentally. Simulations of neuronal networks provide an alternative route to study arbitrarily complex manipulations in morphologically and biophysically detailed models. Here, we present Connectome-Manipulator, a Python framework for rapid connectome manipulations of large-scale network models in SONATA format. In addition to creating or manipulating the connectome of a model, it provides tools to fit parameters of stochastic connectivity models against existing connectomes. This enables rapid replacement of any existing connectome with equivalent connectomes at different levels of complexity, or transplantation of connectivity features from one connectome to another, for systematic study. We employed the framework in a detailed model of rat somatosensory cortex in two exemplary use cases: transplanting interneuron connectivity trends from electron microscopy data and creating simplified connectomes of excitatory connectivity. We ran a series of network simulations and found diverse shifts in the activity of individual neuron populations causally linked to these manipulations.

Approaching the Atomic Limit of Optically-and Electrically-Active Quasi-1D Van Der Waals Crystals Using Carbon and Boron Nitride Nanotube Encapsulation

The realization of stable monolayers from 2D van der Waals (vdW) solids has fueled the search for exfoliable crystals with even lower dimensionalities. To this end, 1D and quasi-1D (q-1D) liquid vdW crystals comprising weakly bound subnanometer-thick chains have been discovered and demonstrated to exhibit nascent physics in the bulk. Although established micromechanical and -phase exfoliation methods have been applied to access single isolated chains from bulk crystals, interchain vdW interactions with nonequivalent strengths have greatly hindered the ability to achieve uniform single isolated chains. In this talk, I will present how encapsulation of the model q-1D vdW pnictogen chalcogenide crystals (Sb2S3 and Sb2Se3) within single-walled carbon nanotubes (CNTs) and boron nitride nanotubes (BNNTs) circumvents the relatively stronger inter-chain vdW interactions between the chains. I will discuss in detail how this methodology allows for the isolation of few nanometer-thick chain bundles and sub-nanometer-thick single chains with structural integrity and crystalline order, as supported by a series of electron microscopy and optical spectroscopy data. Furthermore, I will describe how encapsulation of pnictogen chalcogenides within well-defined nanotubes lead to pronounced blue shift in the optical absorption edges from the near-infrared to the visible range due to quantum confinement effects. I will conclude the talk by briefly describing how the presence of nanoscale to sub-nanoscale defects or discontinuities along the guest-nanotube interface strongly influences the degree of crystalline order of encapsulated single chains and nanostructures. Altogether, the results that I will present serve to solidify the understanding of how q-1D vdW pnictogen chalcogenides crystallize within confined synthetic platforms, thereby opening opportunities in understanding dimension-dependent properties and potential optoelectronic device applications of a plethora of emergent 1D and q-1D vdW solids.

Investigation on the Interaction of Catalyst and Ionomer in AEM Electrolysis

In low temperature electrolysis, anion exchange membrane (AEM) systems combine the advantages of alkaline and proton exchange membrane (PEM) electrolysis in generating high purity hydrogen and reducing material costs from catalysts and component coatings [1]. Recent studies in AEM electrolysis have focused on improving cell performance, minimizing catalyst dissolution and mitigating ionomer/membrane degradation with different operating conditions. Ionomers play a critical role in the electrode because they provide ion conductivity, enhance mechanical support, and create preferred morphologies for electrolyte and produced gas to move [2, 3]. Optimizing catalyst-ionomer interactions by varying ionomer content, chemistries, and forms can accelerate the development of AEM electrolysis in terms of performance enhancement, cost and lifetime.In this work, different forms of ionomer (powdered and dispersed) with two polymer backbones were evaluated in AEM electrolysis cell testing. Ni- and Co-based oxides and IrO2 were applied as anode catalysts. In Figure 1, the anodes with powdered ionomer outperform the dispersed samples. With Co3O4 catalyst, the overpotential can be improved by 0.9 V at 1 A/cm2 (iR-free voltage of Co3O4 with powdered ionomer: 1.68 V at 1 A/cm2). By electrochemical diagnostic and modeling methods, the improved performance with powdered ionomer is attributed to better reaction kinetic from more active area between catalysts and ionomers, less ohmic overpotentials due to better contact between the electrode and the transport layer and preferred transport properties with higher porosity created by powdered ionomer. Scanning electron microscopy data verifies that the anodes with powdered ionomer provide more homogeneous distribution of catalysts and ionomer in the electrode, while dispersed samples have the issues of agglomerates and uneven coverage of catalysts, which could worsen the catalyst utilization and trigger mass transport issues.[1] Ayers, Katherine, et al. "Perspectives on low-temperature electrolysis and potential for renewable hydrogen at scale." Annual review of chemical and biomolecular engineering 10 (2019): 219-239.[2] Lee, Sol A., et al. "Anion exchange membrane water electrolysis for sustainable large‐scale hydrogen production." Carbon Neutralization 1.1 (2022): 26-48.[3] Favero, Silvia, Ifan EL Stephens, and Maria‐Magdalena Titirci. "Anion Exchange Ionomers: Design Considerations and Recent Advances‐An Electrochemical Perspective." Advanced Materials 36.8 (2024): 2308238. Figure 1

Mineral Liberation and Concentration Characteristics of Apatite Comminuted by High-Pressure GRU

Mineral liberation and concentration have always been the core issues in ore processing. The goal of multi-stage crushing and ball milling is liberation because mineral liberation is the foundation of beneficiation. High energy consumption and environmental pollution have always been unavoidable topics. We put forward the method of high-pressure gas rapid unloading (GRU). Particle size followed MR-R distribution. The scanning electron microscopy data showed that the liberation of apatite particles smaller than 4 mm was sufficient by high-pressure GRU methods, and high-grade apatite concentrated in the particle size range of 0.5 to 4 mm. The average grade of the preferred particle size interval was 3%–5% higher than the original ore. Liberation degrees of apatite less than 4 mm are above 88%, which was beneficial for mineral processing. Compared to the traditional crushing method, the GRU method had a higher liberation and concentration in the particle size range of 0.5 to 4 mm. The total energy consumption was about 1.76 kW·h/t, less than that of the traditional crushing method.

Chromomeres, Topologically Associating Domains and Structural Organization of Chromatin Bodies in Somatic Nuclei (Macronuclei) of Ciliates.

In the twentieth century, the textbook idea of packaging genomic material in the cell nucleus and metaphase chromosomes was the presence of a hierarchy of structural levels of chromatin organization: nucleosomes - nucleosomal fibrils -30 nm fibrils - chromomeres - chromonemata - mitotic chromosomes. Chromomeres were observed in partially decondensed chromosomes and interphase chromatin as ~100 nm globular structures. They were thought to consist of loops of chromatin fibres attached at their bases to a central protein core. However, Hi-C and other related methods led to a new concept of chromatin organization in the nuclei of higher eukaryotes, according to which nucleosomal fibrils themselves determine the spatial configuration of chromatin in the form of topologically associating domains (TADs), which are formed by a loop extrusion process and are regions whose DNA sequences preferentially contact each other. Somatic macronuclei of ciliates are transcriptionally active, highly polyploid nuclei. A feature of macronuclei is that their genome is represented by a large number of "gene-sized" (~1-25 kb) or of "subchromosomal" (~50-1700 kb) size minichromosomes. The inactive macronuclear chromatin of "subchromosomal" ciliates usually looks like bodies 100-200 nm in size. The aim of this work was to find out which of the models (chromomeres or TADs) is more consistent with the confocal and electron microscopic data on structural organization of chromatin bodies. Macronuclear chromatin of four "subchromosomal" ciliate species (Bursaria truncatella, Paramecium multimicronucleatum, Didinium nasutum, Climacostomum virens) was examined using electron microscopy and confocal microscopy during regular growth, starvation and encystment. Chromatin bodies ~70-200 nm in size observed in the interphase macronuclei consisted of tightly packed nucleosomes. Some of them were interconnected by one or more chromatin fibrils. Under hypotonic conditions in vitro, chromatin bodies decompacted, forming rosette-shaped structures of chromatin fibrils around an electron-dense centre. When the activity of the macronucleus decreased during starvation or encystment, chromatin bodies assembled into chromonema-like fibrils 100-300 nm thick. This data allows us to consider chromatin bodies as analogues of chromomeres. On the other hand, most likely, the formation of DNA loops in chromatin bodies occurs by the loop extrusion as in TADs. The data obtained is well explained by the model, according to which the chromatin bodies of ciliate macronuclei combine features inherent in both chromomeres and TADs; that is, they can be considered as chromomeres with loops packed in the same way as the loops in TADs.

Electron microscopy method in assessing the quality of cell cryopreservation

During its existence, electron microscopy has become one of the reference methods for assessing the structural and functional state of cells, tissues and organs, and an extensive evidence base has been formed that allows its use in the creation and formation of a biobank. The selection of sources for the literature review was carried out using keywords based on publications over the past 20 years. The publications presented in the review were selected by searching the eLIBRARY.RU, PubMed and Scopus databases. Based on foreign and domestic experience in the work of biobanks, we can distinguish four areas that determine the effectiveness of the use of electron microscopy studies as a component of its work. Firstly, it is control of microbiological contamination of a biological sample. The effectiveness of electron microscopy in detecting contamination of a biological sample with bacteria, fungi and viruses is comparable to the effectiveness of classical microbiological techniques. Secondly, it is a diagnostic tool that allows you to identify or confirm the presence in a sample of a pathogenetic process that is of interest for biobanking: tumor growth, atherosclerotic vessel damage, etc. Thirdly, it is quality control for cryopreservation of samples. A wide range of morphological characteristics of the ultramicroscopic structure of cells and microanatomical formations makes it possible to characterize the quality of cryopreservation and quantify the degree of damage, which contributes to the unification and standardization of biobanking. Transmission electron microscopy is the most informative in this matter. Fourthly, this is the basis for digitalization of the results obtained and the formation of an interdisciplinary biobank repository, which allows the use of “big date” technologies for fundamental research. The compliance of the biobank profile with the economic, scientific and industrial characteristics of the infrastructure of the industry or region is of great importance. Electron microscopy data are successfully combined with the results of molecular studies, which allows the formation of interdisciplinary metadata databases suitable for interregional and interdisciplinary scientific integrations. The latter makes it possible to use electron microscopy data to solve a wide range of applied and interdisciplinary problems. The above allows us to consider scanning and transmission microscopy methods as one of the key methods in the development of biobanking in the region.

Integration by design: driving mineral system knowledge using multi-modal, collocated, scale-consistent characterisation

Abstract. Recent decades have seen an exponential rise in the application of machine learning in geoscience. However, fundamental differences distinguish geoscience data from most other data types. Geoscience datasets are typically multi-dimensional, and contain 1D (drill holes), 2D (maps or cross-sections), and 3D volumetric and point data (models/voxels). Geoscience data quality is a product of the data's resolution and the precision of the methods used to acquire them. The dimensionality, resolution, and precision of each layer within a geoscience dataset translate into limitations to the spatiality, scale, and uncertainty of resulting interpretations. Historically, geoscience datasets were overlaid cartographically to incorporate subjective, experience-driven knowledge and variances in scale and resolution. These nuances and limitations that underpin the reliability of automated interpretation are well understood by geoscientists but are rarely appropriately transferred to data science. For true integration of geoscience data, such issues cannot be overlooked without consequence. To apply data analytics to complex geoscience data (e.g. hydrothermal mineral systems) effectively, methodologies that characterise the system quantitatively at a common scale, using collocated analyses, should be sought. This paper provides research and exploration insights from an innovative district-wide, scale-integrated geoscience data project, which analysed 1590 samples from 23 mineral deposits and prospects across the Cloncurry district, Queensland, Australia. Nine different analytical techniques were used, including density, magnetic susceptibility, remanent magnetisation, anisotropy of magnetic susceptibility, radiometrics, conductivity, automated mineralogy based on scanning electron microscopy (SEM), geochemistry, and short-wave infrared (SWIR) hyperspectral data with 561 columns of scale-integrated data (+2151 columns of SWIR data). All data were collected on 2.2 cm × 2.5 cm sample cylinders, a scale at which the confidence in the coupling of data from techniques can be high. These data are integrated by design to eliminate the need to downscale coarser measurements via assumptions, inferences, inversions, and interpolations. This scale-consistent approach is critical to the quantitative characterisation of mineral systems and has numerous applications in mineral exploration, such as linking alteration paragenesis with structural controls and petrophysical zonation. The Cloncurry METAL dataset is made freely available via the AuScope Data Repository: https://doi.org/10.60623/82trleue (Austin et al., 2024).

RETRACTION: High-Resolution Imaging of Human Cancer Proteins Using Microprocessor Materials.

M. J. Solares, G. M. Jonaid, W. Y. Luqiu, S. Berry, J. Khadela, Y. Liang, M. C. Evans, K. J. Pridham, W. J. Dearnaley, Z. Sheng and D. F. Kelly, "High-Resolution Imaging of Human Cancer Proteins Using Microprocessor Materials," ChemBioChem, 23, no. 17 (2022), e202200310, https://doi.org/10.1002/cbic.202200310. The above article, published online on 5 July 2022 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Ruben Ragg; and Wiley-VCH GmbH. The retraction has been agreed following a thorough peer review process conducted by the author's institution, Penn State. The editors' own independent investigation confirmed that density map for the p53 dimer does not align well with the model for Figures 2B and S3 A. Furthermore, it was found that the coordinate and map files associated with the article available in the Protein Data Bank [PDB accession codes 8F2I (p53 monomer), 8F2H (p53 dimer)] and Electron Microscopy Data Bank [EMDB accession codes EMD28817 (p53 monomer), EMD28816 (p53 dimer)] exhibit poor alignment throughout. In addition, the authors did not provide original research data, maps and models in question, to justify the findings. The editors' own independent investigation confirmed that the conclusions of this manuscript are not sufficiently supported. Author D. F. Kelly responded to our notice of retraction, but did not state their agreement nor disagreement. Author G. M. Jonaid agrees with the retraction. All other authors did not respond to our notice regarding the retraction.