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Photocatalytic water-splitting represents a promising avenue for clean hydrogen production, necessitating an in-depth understanding of the photocatalytic reaction mechanism. The majority of the photocatalytic materials need cocatalysts to enhance the photo-oxidation or reduction reactions. However, the working mechanism, such as collecting charge carriers or reducing the reaction barrier, is not clear because they disperse inhomogeneously on a surface, and it is difficult to follow the local charge carrier behavior. This study employs the pattern-illumination time-resolved phase microscopy (PI-PM) method to unravel the spatial charge carrier behavior in photocatalytic systems, utilizing time-resolved microscopic image (refractive index change) sequences and their clustering analyses. This approach is robust for studying the change in local charge carrier behavior. We studied two major cocatalyst effects on photocatalysts: TiO2 with/without Pt and hematite with/without CoPi. The PI-PM method, supported by charge type clustering and the effects of scavengers, allowed for the analysis of local activity influenced by cocatalysts. This approach revealed that the introduction of cocatalysts alters the local distribution of charge carrier behavior and significantly impacts their decay rates. In TiO2 systems, the presence of Pt cocatalysts led to a local electron site on the micron scale, extending the lifetime to a few tens of microseconds from a few microseconds. Similarly, in hematite films with CoPi, we observed a notable accumulation of holes at cocatalyst sites, emphasizing the role of cocatalysts in enhancing photocatalytic efficiency. The study's findings highlight the complexity of charge carrier dynamics in photocatalytic processes and the significant influence of cocatalysts. [ABSTRACT FROM AUTHOR]

High tilt angle (45 °) ferroelectric liquid crystal (F L C) in surface stabilized geometry, having no chiral smectic A (S m A ∗) phase, has been studied for the reorientation of the smectic layers near the transition temperature (T c). The electro-optical studies have shown the stripe domain formation in which the liquid crystal molecules are aligned along the rubbing direction, but the smectic layers are tilted away from the rubbing direction at room temperature. In such high tilt angle F L C s , the molecular alignment and smectic layer formation start from bottom and top rubbed grooves at T c. The domain formation of the FLC takes place in the middle of the top and bottom surfaces due to the frustration of the dipolar interaction. The smectic layer switching is observed by optical microscopy and confirmed by the dielectric spectroscopy method near T c of S m C ∗ and chiral nematic phases. Domain switching has shown a larger switching angle than the molecular tilt angle within the smectic layer. These studies are expected to be significant for understanding the smectic layer structure and the domain switching process, which may pave the way for large optical switching devices. [ABSTRACT FROM AUTHOR]

Fast carrier dynamics in organic thin-film transistors (OTFTs) was investigated by time-resolved electrostatic force microscopy (tr-EFM). We found that the carrier diffusion in the OTFTs proceeded in two stages: fast diffusion and slow diffusion. By applying the instantaneous frequency method to EFM, the temporal evolution of the spatial distribution of fast carriers in the channel region of the OTFTs, which took place on the timescale of several hundreds of nanoseconds, was evaluated. The inhomogeneous distribution of the local decay time constant showed that the carrier diffusion of the OTFTs was limited by the grain boundaries between each crystalline region. The quantitative capability of the method was verified by comparing the values of the carrier mobility estimated by the tr-EFM measurement and a numerical simulation. The mobility estimated from the experiment and the simulation showed good agreement, showing the possibility of the tr-EFM to evaluate the time evolution of dynamic phenomena in semiconductor devices. [ABSTRACT FROM AUTHOR]

Colloidal probes are often used in force microscopy when the geometry of the tip–sample interaction should be well controlled. Their calibration requires an understanding of their mechanical response, which is very sensitive to the details of the force sensor consisting of a cantilever and the attached colloid. We present some analytical models to describe the dynamics of the cantilever and its load positioned anywhere along its length. The thermal noise calibration of such probes is then studied from a practical point of view, leading to correction coefficients that can be applied in standard force microscope calibration routines. Experimental measurements of resonance frequencies and thermal noise profiles of raw and loaded cantilevers demonstrate the validity of the approach. [ABSTRACT FROM AUTHOR]

Poly(ethylene oxide) (PEO) is a well-known biocompatible polymer and has widely been used for medical applications. Recently, we have investigated the dynamic behavior of hydration water in the vicinity of PEO chains at physiological temperature and shown the presence of slow water with diffusion coefficient one order of magnitude less than that of bulk water. This could be evidence for the intermediate water that is critical for biocompatibility; however, its detailed dynamical features were not established. In this article, we analyze the quasi-elastic neutron scattering from hydration water through mode distribution analysis and present a microscopic picture of hydration water as well as its relation to cold crystallization. [ABSTRACT FROM AUTHOR]

Monoolein-based liquid crystal phases are established media that are researched for various biological applications, including drug delivery. While water is the most common solvent for self-assembly, some ionic liquids (ILs) can support lipidic self-assembly. However, currently, there is limited knowledge of IL-lipid phase behavior in ILs. In this study, the lyotropic liquid crystal phase behavior of monoolein was investigated in six protic ILs known to support amphiphile self-assembly, namely ethylammonium nitrate, ethanolammonium nitrate, ethylammonium formate, ethanolammonium formate, ethylammonium acetate, and ethanolammonium acetate. These ILs were selected to identify specific ion effects on monoolein self-assembly, specifically increasing the alkyl chain length of the cation or anion, the presence of a hydroxyl group in the cation, and varying the anion. The lyotropic liquid crystal phases with 20–80 wt. % of monoolein were characterized over a temperature range from 25 to 65 °C using synchrotron small angle x-ray scattering and cross-polarized optical microscopy. These results were used to construct partial phase diagrams of monoolein in each of the six protic ILs, with inverse hexagonal, bicontinuous cubic, and lamellar phases observed. Protic ILs containing the ethylammonium cation led to monoolein forming lamellar and bicontinuous cubic phases, while those containing the ethanolammonium cation formed inverse hexagonal and bicontinuous cubic phases. Protic ILs containing formate and acetate anions favored bicontinuous cubic phases across a broader range of protic IL concentrations than those containing the nitrate anion. [ABSTRACT FROM AUTHOR]

Time-resolved pump–probe and two-dimensional spectroscopy are widely used to study ultrafast chemical and biological processes in solutions. However, the corresponding signals at long times can be contaminated by molecular photothermal effects, which are caused by the nonradiative heat dissipation of photoexcited molecules to the surroundings. Additionally, molecular diffusion affects the transient spectroscopic signals because photoexcited molecules can diffuse away from the pump and probe beam focuses. Recently, a theoretical description of molecular photothermal effects on time-resolved IR spectroscopy was reported. In this work, I consider the molecular photothermal process, molecular diffusion, and sample flow to develop a generalized theoretical description of time-resolved spectroscopy. The present work can be used to interpret time-resolved spectroscopic signals of electronic or vibrational chromophores and understand the rate and mechanisms of the conversion of high-frequency molecular electronic and vibrational energy to solvent kinetic energy in condensed phases. [ABSTRACT FROM AUTHOR]

In material processing and handling processes, premixed interlayer often replace the ideal Ni/Al interface, which would become a new origin of alloying reaction. This work investigates shock-induced reaction mechanism and kinetics of premixed Ni/Al nanolaminates with molecular dynamics simulations and theoretical analysis. The reaction is found to be driven by the crystallization evolution in premixed interlayer and the diffusion of premixed atoms. Among them, multi-stage reaction patterns are strongly manifested by the crystallization evolution characteristics. Specifically, "crystallization-dissolution-secondary growth" and "crystallization-dissolution" of B2 phase respectively correspond to the solid-state and solid-liquid reaction cases, where crystallizations are fitted well by Johnson–Mehl–Avrami kinetics model. Interestingly, the different growth mechanisms of B2 grain are revealed, namely nuclei coalescence and atomic diffusion. Moreover, the analysis of microscopic diffusion theory indicates a certain non-random diffusion nature for solid-state reaction initiation, but near-purely random diffusion for solid-liquid reaction initiation. The diffused Al atoms possess a limited diffusion coefficient and enhanced diffusion correlation, resulting in extremely slow mixing rate in Ni layer. In addition, the influence law of Ni concentration in premixed interlayer on reactivity parameters can be quantitatively described by a quadratic function. [ABSTRACT FROM AUTHOR]

Photoinduced force microscopy (PiFM) is a technique for nanoscale characterization of optically active materials. For correct data analysis, it is important to understand and recognize potential artifacts. In this study, we provide a Fourier-based framework for the different origins of the photoinduced force, including the photothermal motion of the atomic force microscopy (AFM) tip in PiFM measurements. We use individual gold nanoparticles as a model system to explore such tip-related phenomena and to demonstrate the benefits of three-dimensional analysis of the photoinduced force. Comparison of the in-phase heterodyne PiFM signal and the derivative of the tip–sample interaction, ∂ ⟨ k ts ⟩ / ∂ z c , directly reveals a photothermal origin for the PiFM signal in our experiments. Furthermore, we observe a lateral photothermal vibration of the tip apex induced by tip asymmetry. This lateral vibration emphasizes the importance of considering the motion of the AFM tip during data analysis. The improved lateral resolution conferred by ∂ ⟨ k ts ⟩ / ∂ z c can lead to misinterpretation. Our findings highlight that meticulous data analysis is required to ensure the correct interpretation of PiFM data. [ABSTRACT FROM AUTHOR]

Arterial wall active mechanics are driven by resident smooth muscle cells, which respond to biological, chemical, and mechanical stimuli and activate their cytoskeletal machinery to generate contractile stresses. The cellular mechanoresponse is sensitive to environmental perturbations, often leading to maladaptation and disease progression. When investigated at the single cell scale, however, these perturbations do not consistently result in phenotypes observed at the tissue scale. Here, a multiscale model is introduced that translates microscale contractility signaling into a macroscale, tissue-level response. The microscale framework incorporates a biochemical signaling network along with characterization of fiber networks that govern the anisotropic mechanics of vascular tissue. By incorporating both biochemical and mechanical components, the model is more flexible and more broadly applicable to physiological and pathological conditions. The model can be applied to both cell and tissue scale systems, allowing for the analysis of in vitro, traction force microscopy and ex vivo, isometric contraction experiments in parallel. When applied to aortic explant rings and isolated smooth muscle cells, the model predicts that active contractility is not a function of stretch at intermediate strain. The model also successfully predicts cell-scale and tissue-scale contractility and matches experimentally observed behaviors, including the hypercontractile phenotype caused by chronic hyperglycemia. The connection of the microscale framework to the macroscale through the multiscale model presents a framework that can translate the wealth of information already collected at the cell scale to tissue scale phenotypes, potentially easing the development of smooth muscle cell-targeting therapeutics. [ABSTRACT FROM AUTHOR]

Electric force microscopy probes the statistics of electric field fluctuations from a sample surface, both through measurement of the noncontact friction exerted on the oscillating charged probe and by determination of the power spectrum of stochastic probe frequency fluctuations, referred to as "jitter." Here we calculate the frequency jitter power spectrum determined over a conducting sample of finite thickness, whose response is characterized by a dielectric function that is wavevector-dependent. These calculations complement previous predictions of the coefficient of noncontact friction in an electric force microscopy measurement for the same model, and also previous predictions of the jitter power spectrum for a dielectric continuum. The inclusion both of a finite sample thickness and a wavevector-dependent dielectric response can significantly enhance the magnitude of the predicted jitter spectrum for a conductor, relative to a simpler model of an infinitely thick dielectric continuum. These calculations provide a baseline prediction of the jitter power spectrum generated by the dynamics of conduction electrons in a metal sample. [ABSTRACT FROM AUTHOR]

The elastic behavior of nematics is commonly described in terms of the three so-called bulk deformation modes, i.e., splay, twist, and bend. However, the elastic free energy contains also other terms, often denoted as saddle–splay and splay–bend, which contribute, for instance, in confined systems. The role of such terms is controversial, partly because of the difficulty of their experimental determination. The saddle–splay (K24) and splay–bend (K13) elastic constants remain elusive also for theories; indeed, even the possibility of obtaining unambiguous microscopic expressions for these quantities has been questioned. Here, within the framework of Onsager theory with Parsons–Lee correction, we obtain microscopic estimates of the deformation free energy density of hard rod nematics in the presence of different director deformations. In the limit of a slowly changing director, these are directly compared with the macroscopic elastic free energy density. Within the same framework, we derive also closed microscopic expressions for all elastic coefficients of rodlike nematics. We find that the saddle–splay constant K24 is larger than both K11 and K22 over a wide range of particle lengths and densities. Moreover, the K13 contribution comes out to be crucial for the consistency of the results obtained from the analysis of the microscopic deformation free energy density calculated for variants of the splay deformation. [ABSTRACT FROM AUTHOR]

Polarization plays a crucial role in understanding the interaction of fluorescent molecules in a light field. We report the study on the effect of a field–dipole interaction under polarization light-sheet fluorescence microscopy using the vectorial theory of light. The molecule is suitably modeled as a radiating electric dipole in a polarized electric field (both linear and random), and the system point spread function (PSF) is determined for different orientations of the dipole (both fixed and random). PSF analysis and contour plots suggest distinct nature of a field distribution in each case, indicating the importance of a field–dipole interaction for high-quality fluorescence imaging. The analysis suggests that the field spreads gradually along the polarization axis at a high numerical aperture (NA) of the objective lens, whereas it is more isotropic and homogeneous at low NA. Moreover, fast changes are not observed at low NA (i.e., far from the central lobe in the field contour plots), suggesting the absence of high-frequency components. However, sidelobes are prominent for linear polarized (along x) light. On the other hand, rapid variations are evident for randomly polarized light, depicting the presence of high spatial frequencies in the system optical transfer function. The other significant observation is the distinct frequency spectrum (both k x and k y) for random and fixed dipoles, indicating the significance of dipole orientation in a light-sheet field. Compared to the point-illumination-based fluorescence microscopy, sheet based polarization technique provides a high signal-to-noise ratio, a uniform field, an order large field of view, and critical information (related to the micro-environment of a dipole and its short-range interactions). The study is expected to facilitate polarization-sensitive investigation of large biological specimens (both fixed and live). [ABSTRACT FROM AUTHOR]

Quantum diamond magnetometers using lock-in detection have successfully detected weak bio-magnetic fields from neurons, a live mammalian muscle, and a live mouse heart. This opens up the possibility of quantum diamond magnetometers visualizing microscopic distributions of the bio-magnetic fields. Here, we demonstrate a lock-in-based widefield quantum diamond microscopy, achieving a mean volume-normalized per-pixel sensitivity of 43.9 nT μ m 1.5 / H z 0.5 . We optimize the sensitivity by implementing a double resonance with hyperfine driving and magnetic field alignment along the ⟨ 001 ⟩ orientation of the diamond. Additionally, we show that sub-ms temporal resolution (∼ 0.4 ms) can be achieved while keeping the per-pixel sensitivity at a few tens of nanotesla per second using quantum diamond microscopy. This lock-in-based diamond quantum microscopy could be a step forward in mapping functional activity in neuronal networks in micrometer spatial resolution. [ABSTRACT FROM AUTHOR]

Localized lattice distortions in GaN substrates can serve as nucleation sites for epitaxial macro-steps and macro-terraces. These detrimental macro-scale features give rise to optically hazy homoepitaxial GaN surfaces. After nucleating, these macro-features grow laterally along the surface and coalesce, leading to significant coverage of the wafer surface. Dot-core GaN substrates consisting of a periodic array of cores were used as a defect-engineered system, where dislocations are intentionally concentrated at the cores. The high density of threading dislocations at the cores induced localized lattice distortions. These distortions are associated predominantly with lattice tilt on the order of hundreds of arcsec across ∼0.5 mm laterally along the wafer surface. The resulting macro-features that nucleated at these localized distorted sites were made up of macro-terraces with lengths ranging ∼30–∼150 μm and macro-step heights ranging ∼200–∼400 nm. Another source of localized distortion was threading screw dislocations or GaN nanopipes that resulted in spiral growth and hillock formation. Based on x-ray topography and optical microscopy measurements, we speculate that the coalescence of hillocks evolves into macro-terraces and macro-steps. While previous studies focused on the substrate miscut as a means to control macro-feature formation, we show that localized lattice tilt from defects is another important contributor to macro-feature formation. [ABSTRACT FROM AUTHOR]

The aim of this paper was to investigate intumescent coatings based on polyfurfuryl alcohol (PFA) resin as a binder benefiting from high char yield and low smoke emission. To this end, the coatings composition in terms of PFA binder resin, long oil alkyd plasticizing resin, TiO2 pigment, and flame-retardant additives (FR) was changed as input parameters according to a mixture design-of-experiments. The corresponding changes in the backside temperature of mild steel substrate (Tb), residual char expansion ratio, limiting oxygen index, and char residue (wt% @1000 °C) were studied as the response variables describing fire performance characteristics of the coatings. The results showed that the backside temperature of the plate increased and the expansion ratio decreased with increasing in the alkyd resin concentration. Also, the flame-retardant efficiency of coatings strongly depends on the content of FR additives. When the content of PFA and alkyd resin was increased at a high level (35 and 4 wt%, respectively), the Tb of the coated plates reached 415 °C rapidly, due to the cracking of the coating and the lower concentration of FR additives. However, the formula with higher FR content, i.e., 68 wt%, showed the lowest Tb value ca. 128 °C. Flame-retardant characteristics directly depended on the expansion ratio of the coatings and the morphology of the char layer remaining on the substrate after the flame test; therefore, coatings with a higher expansion ratio showed lower backside temperature. The findings were supported by examining of the remaining char morphology after a flame test by optical microscopy and validated by comparing the predicted and actual responses for optimization. The value of absolute relative deviation was obtained in the range of 1.6–7.9, which indicates a good agreement between the proposed and experimental results. [ABSTRACT FROM AUTHOR]

Monodispersed spherical particles of γ- and α-alumina were synthesized by urea-based homogeneous precipitation, using potassium sulfate and aluminum nitrate as the precursor and urea as a precipitating agent. The influence of various synthesis parameters like concentration of reactants, temperature, and reaction time, on the morphological features of alumina were investigated. Results showed that all the experimental parameters had a considerable effect on the morphology of the synthesized alumina, and control of these parameters resulted in monodispersed spherical particles with good dispensability and filtering performance. Extensive optimization of the experimental parameters led to produced alumina precursors with spherical morphology and an average particle size of 610 nm. The precipitated solids were characterized by various techniques and it was noted that the as-prepared particles were amorphous. Relatively well-dispersed and crystalline γ- and α-Al2O3 with higher sintering activity were obtained by calcining the as-synthesized precursors at 1000 and 1200 °C, respectively. The crystallographic results showed that crystallite size increased with an increase in annealing temperature. It was observed that the crystallite size of γ-Al2O3 was much smaller (5.71 nm ± 7.21%) than α-Al2O3 (35.40 nm) ± 4.58%. The Scanning electron microscopic analysis of the calcined alumina showed that the particle morphology was retained to a greater extent after calcination. The synthesized alumina particles can be used as a reinforcement filler in the Ni/Al2O3 composite coatings to enhance the tribological and mechanical properties of Ni-composite coating on a steel surface. The incorporated alumina particles in the composite may improve the properties of the coatings. [ABSTRACT FROM AUTHOR]

Effect of the presence of NaCl, Na2SO4, MgCl2 and CaCl2 as smart water with different salinity was investigated in the formation and stability of the emulsion. Three methods were used to evaluate the emulsion stability. The first method, the amount of water separated from each sample, after 14 days of emulsion preparation, was recorded and examined. Bottle test was the second method to evaluate the stability during which the emulsion samples were monitored for up to 14 days. In the third method, a microscopic image was taken from each sample, and the mean droplet area for each sample was recorded. By adding Na2SO4 to a concentration of 8000 ppm in distilled water, the most stable emulsion was obtained, which was completely stable for up to 48 h, and after two weeks of preparation of the emulsion, almost only 10% of the aqueous phase was separated from the emulsion. And the microscopic image showed that in this case, the mean droplet area is 17 μm2, which, compared to other salts in different concentrations, had the lowest amount. On the other hand, salt NaCl with a concentration of 40,000 ppm formed the most unstable emulsion, which after 14 days, almost the entire aqueous phase was separated from the emulsion. By microscopic image analysis, the average droplets area was 58 μm2 for NaCl with 40000 ppm concentration, which is the highest value compared to other samples. While seawater was used to make the emulsion, ten times diluted seawater formed the most stable emulsion. [ABSTRACT FROM AUTHOR]

An effective, GFP‐inspired fluorescent Zn2+ sensor is developed for two–photon microscopy and related biological application that features an 8‐methoxyquinoline moiety. Excellent photophysical characteristics including a 37‐fold fluorescence enhancement with excitation and emission maxima at 440 nm and 505 nm, respectively, as well as a high two–photon cross–section of 73 GM at 880 nm are reported. Based on the experimental data, the relationship between the structure and properties was elucidated and explained backed up by DFT calculations, particularly the observed PeT phenomenon for the turn–on process. Biological validation and detailed experimental and theoretical characterization of the free and the zinc–bound compounds are presented. [ABSTRACT FROM AUTHOR]

The use of synthetic and natural resins in the fixation of organomineral matter for further studies is common, e.g. in the micromorphological study of soils, since the procedure of making thin sections includes the impregnation of the sample with the filling materials (resins). At the same time, their effect on the soil structure remains poorly known. In this article, an experiment to study the impact of synthetic and natural resins on the nano- and microstructure of soil during impregnation is considered. First data on the characteristics of resins frequently used in laboratories, as well as on their effects on the structure of soil samples have been obtained with small-angle X-ray scattering and computed tomography techniques. The X-ray transparency of fixing materials was detected. Subsequent impregnation of the AU horizon fraction from Haplic Chernozems of Kursk oblast by fixing materials allowed establishing their influence on the change in size of soil nanostructural heterogeneities. The experiment with different horizons of Protosalic Solonetz attests to a decrease in the size of nanoheterogeneities with depth in the impregnated soil as compared with that in the native soil. At the microlevel, a decrease in microporosity within the first percent after polymerization of the fixing material has been proved. As a result of studies of nanoheterogeneities in the soil, scanning parameters have been experimentally selected at the BioSAS station of the Kurchatov's synchrotron radiation source. The nanostructure of soil core samples and separate fractions has been studied for the first time at this station. The above results can be used in sample preparation and further analysis of organomineral objects (soils, rocks) for a number of studies that require fixation of the substance structure at different dimensional levels. [ABSTRACT FROM AUTHOR]

This study undertakes vacuum pressureless brazing of SiC ceramics with TiSi 2 powder, achieving MAX bonding. Microscopic characterization elucidates the microstructural evolution of the joined seam across various brazing temperatures and durations. The formation process of Ti 3 SiC 2 is detailed through thermodynamic and kinetic analyses. At 1550 ℃ for 30 min or 1600 ℃ for 15 min, the filler undergoes in-situ reaction with SiC, yielding a dense, continuous Ti 3 SiC 2 (MAX) phase, with no other phases observed. This suggests that increased temperature reduces MAX synthesis time. However, prolonged brazing causes voids in the center of the joined seam. Si volatilization was key for Ti 3 SiC 2 in-situ formation, and this reaction equation was proposed. Maximum average shear strength at room temperature is 127.15 MPa at 1550 ℃ for 30 min and 118.15 MPa at 1600 ℃ for 15 min. • In-situ formation of Ti 3 SiC 2 for pressureless joining of SiC ceramics. • Explain the growth principles of Ti 3 SiC 2 layer through the Ti-Si-C ternary phase diagram and kinetic principles. • Joint shear strength: 127.15 MPa. Explain strength variations using microscopic analysis. [ABSTRACT FROM AUTHOR]

Introduction: This study aims to evaluate the effectiveness and reliability of the utilization for clinical reporting of the evaluation of digital images of bone marrow aspirates by morphologists and their comparability with the classic microscopic morphological evaluation. Methods: We scanned 180 consecutive bone marrow needle aspirates smears using the "Metafer4 VSlide" whole slide imaging (WSI) digital scanning system. We evaluated the statistical comparability and the risk of bias of the microscopic readings with those performed on the screen on the digitized medullary images. Results: The evaluation of cellularity on the screen was equivalent, with a higher frequency of "normal" than the analysis of digital preparations. The means and medians of the percentage values obtained on the different cell populations with the microscopic and digital reading were comparable as the main categories are concerned, with an average difference equal to 0 for the neutrophilic and eosinophilic granulocytic series, at −0.2% for the total myeloid cells, at 1.2% for the erythroid series, at −0.4% for the lymphocytes and at −0.4% for the blasts. Dysplastic features were consistently identified in 69/71 cell lineages. Conclusion: Our study demonstrated that screen evaluation of digitized bone marrow needle aspirates provides quantitative and qualitative results comparable to traditional microscopic analysis of the corresponding slide smears. Digital images offer significant benefits in reducing the workload of experienced operators, reproducibility and sharing of observations, and image preservation. Even in routine diagnostic activities, their use does not alter the quality of the results obtained in evaluating bone marrow needle aspirates. [ABSTRACT FROM AUTHOR]

Background: The MC‐80 (Mindray, Shenzhen, China), a newly available artificial intelligence (AI)‐based digital morphology analyzer, is the focus of this study. We aim to compare the leukocyte differential performance of the Mindray MC‐80 with that of the Sysmex DI‐60 and the gold standard, manual microscopy. Methods: A total of 100 abnormal peripheral blood (PB) smears were compared across the MC‐80, DI‐60, and manual microscopy. Sensitivity, specificity, predictive value, and efficiency were calculated according to the Clinical and Laboratory Standards Institute (CLSI) EP12‐A2 guidelines. Comparisons were made using Bland–Altman analysis and Passing‐Bablok regression analysis. Additionally, within‐run imprecision was evaluated using five samples, each with varying percentages of mature leukocytes and blasts, in accordance with CLSI EP05‐A3 guidelines. Results: The within‐run coefficient of variation (%CV) of the MC‐80 for most cell classes in the five samples was lower than that of the DI‐60. Sensitivities for the MC‐80 ranged from 98.2% for nucleated red blood cells (NRBC) to 28.6% for reactive lymphocytes. The DI‐60's sensitivities varied between 100% for basophils and reactive lymphocytes, and 11.1% for metamyelocytes. Both analyzers demonstrated high specificity, negative predictive value, and efficiency, with over 90% for most cell classes. However, the DI‐60 showed relatively lower specificity for lymphocytes (73.2%) and lower efficiency for blasts and lymphocytes (80.1% and 78.6%, respectively) compared with the MC‐80. Bland–Altman analysis indicated that the absolute mean differences (%) ranged from 0.01 to 4.57 in MC‐80 versus manual differential and 0.01 to 3.39 in DI‐60 versus manual differential. After verification by technicians, both analyzers exhibited a very high correlation (r = 0.90–1.00) with the manual differential results in neutrophils, lymphocytes, and blasts. Conclusions: The Mindray MC‐80 demonstrated good performance for leukocyte differential in PB smears, notably exhibiting higher sensitivity for blasts identification than the DI‐60. [ABSTRACT FROM AUTHOR]

In the Aumühle quarry of the Ries impact structure, moderately shocked clasts from the Variscan basement occur sandwiched between overlying suevite and components derived from the Mesozoic sedimentary cover of the underlying Bunte Breccia without distinct shock effects. We analyzed the clasts by optical microscopy, scanning electron microscopy (SEM/EDS/EBSD), and Raman spectroscopy to unravel their emplacement relation to the overlying suevite and the sediment-rock clasts of the Bunte Breccia. Clasts sizes range up to few decimeters and are embedded in a fine-grained lithic matrix; no impact-melt fragments are observed. Amphibolite clasts contain maskelynite with few lamellar remnants of feldspar, indicating shock pressures of 28–34 GPa. Amphiboles have cleavage fractures and ( 1 ¯ 01) mechanical twins suggesting differential stresses > 400 MPa. Felsic gneiss components have optically isotropic SiO2 indicative of shock pressures ≈35 GPa. Metagranite cataclasite clasts contain shocked calcite aggregates and quartz with a high density of fine rhombohedral planar deformation features indicating shock pressures ≈20 GPa. The moderately shocked basement clasts originate from deeper levels of the transient cavity and lower radial distance to the center of the structure compared to the sediment-rock clasts. Both were ballistically ejected during crater excavation. In accordance with palaeo- and rock magnetic data, they were mixed during turbulent deposition at the top of the Bunte Breccia before the emplacement of suevite. The high amount of basement clasts below suevite and on top of the underlying Bunte Breccia is consistent with the commonly reported inverse stratigraphy in the Ries impact structure. [ABSTRACT FROM AUTHOR]

Light microscopy facilities vary in the number of imaging systems and the scope of technologies they support. Each facility must craft an identity through the selection of equipment and development of staff in order to serve the needs of its local research environment. The process of crafting a light microscopy facility can be compared to curation of an art exhibition: great care should be given to the selection and placement of each object in order to make a coherent statement. Lay Description: Light microscopy facilities vary in the number of imaging systems and the scope of technologies they support. Each facility must develop an identity through the selection of equipment and development of staff in order to serve the needs of its local research environment. The process of crafting a light microscopy facility can be compared to curation of an art exhibition: great care should be given to the selection and placement of each object in order to make a coherent statement. [ABSTRACT FROM AUTHOR]

Equipment demonstrations (demos) play an important role in the evaluation of new systems. As well as the excitement of exploring emerging technologies, a well‐organised demo can help guide procurement decisions and support funding applications. However, it is easy to underestimate the substantial effort required both before and following the demo to maximise its potential impact. Here, we discuss how our approach to demos at the Crick Advanced Light Microscopy Science and Technology Platform (CALM‐STP) has evolved over the last few years, emphasising the importance of a documented approach that combines quantitative with qualitative comparisons and engages with your user base in order to build up support for any potential system purchase. [ABSTRACT FROM AUTHOR]

The successful operation of a light microscopy core facility depends also on the initial setup of its infrastructure. This article covers the aspects of location selection and room planning and what environmental factors need to be considered. These include light, temperature, vibrations as well as the basic installations needed for microscope operation. LAY DESCRIPTION: Sensitive instruments like the light microscopes used in biomedical research require placement in a suitable surrounding to operate properly. The factors affecting the microscopes' performance include room light, temperature, humidity and even vibrations coming from other areas of the building and its surroundings. When setting up a centralised core facility for light microscopy, these factors should be considered in the planning. The article provides an overview of these influencing factors and covers mitigating approaches and strategies how to account for them. [ABSTRACT FROM AUTHOR]

The accelerating pace of technological advancements necessitates specialised expertise and cutting‐edge instruments to maintain competitive research in life sciences. Core facilities – collaborative laboratories equipped with state‐of‐the‐art tools and staffed by expert personnel – are vital resources that support diverse scientific endeavours. However, their adoption in lower‐income communities has been comparatively stagnant due to both financial and cultural challenges. This paper explores the perils of not supporting core facilities on national research enterprises, underscoring the need for balanced investments in discovery science and crucial infrastructure support. We explore the implications from the perspectives of funders, university leaders and lab heads. We advocate for a paradigm shift to recognise these facilities as essential components of national research efforts. Core facilities are positioned not as optional but as strategic investments that can catalyse breakthroughs, particularly in environments with limited resources. [ABSTRACT FROM AUTHOR]

Microscopy core facilities are increasingly utilised research resources, but they are generally only available to users within the host institution. Such localised access misses an opportunity to facilitate research across a broader user base. Here, we present the model of an open‐access microscopy facility, using the Advanced Imaging Center (AIC) at Howard Hughes Medical Institute Janelia Research Campus as an example. The AIC has pioneered a model whereby advanced microscopy technologies and expertise are made accessible to researchers on a global scale. We detail our experiences in addressing the considerable challenges associated with this model for those who may be interested in launching an open‐access imaging facility. Importantly, we focus on how this model can empower researchers, particularly those from resource‐constrained settings. [ABSTRACT FROM AUTHOR]

The low reproducibility of scientific data published in articles has recently become a cause of concern in many scientific fields. Data involving light microscopy is no exception. The low awareness of researchers of the technologies they use in their research has been identified as one of the main causes of the problem. Potential solutions have hinted at the need to improve technological and methodological education within research. Despite the pivotal role of microscopy core facilities in the education of researchers being well documented, facility staff (FS) often learn their trade on the job, without receiving themselves any structured education about the technology they teach others to use. Additionally, despite endorsing an important role at the highest level of education, most FS never receive any training in pedagogy, the field of research on teaching and learning methods. In this article, we argue that the low level of awareness that researchers have of microscopy stems from a knowledge gap formed between them and microscopy FS during training routines. On the one hand, FS consider that their teaching task is to explain what is needed to produce reliable data. On the other, despite understanding what is being taught, researchers fail to learn the most challenging aspects of microscopy, those involving their judgement and reasoning. We suggest that the misunderstanding between FS and researchers is due to FS not being educated in pedagogy and thus often confusing understanding and learning. To bridge this knowledge gap and improve the quality of the microscopy education available to researchers, we propose a paradigm shift where training staff at technological core facilities be acknowledged as full‐fledged teachers and offered structured education not only in the technology they teach but also in pedagogy. We then suggest that training routines at facilities be upgraded to follow the principles of the Constructive Alignment pedagogical method. We give an example of how this can be applied to existing microscopy training routines. We also describe a model to define where the responsibility of FS in training researchers begins and ends. This involves a major structural change where university staff involved in teaching research technologies themselves receive appropriate education. For this to be achieved, we advocate that funding agencies, universities, microscopy and core facility organisations mobilise resources of time and funding. Such changes may involve funding the creation and development of 'Train‐the‐trainer' type of courses and giving incentives for FS to upgrade their technological and pedagogical knowledge, for example by including them in career paths. We believe that this paradigm shift is necessary to improve the level of microscopy education and ultimately the reproducibility of published data. [ABSTRACT FROM AUTHOR]

Core facilities are research laboratories staffed by professional scientists who can provide access, training, support, and maintenance for the utilisation of highly specialised instrumentation. Microscopy core facilities support researchers working in many areas with wide ranging imaging needs. The companies that manufacture, sell, and service advanced microscopy instrumentation often develop strong and mutually beneficial relationships with their customers, which sometimes lead to contractual agreements with academic research institutions, resulting in so‐called 'branded' core facilities. These academic‐industrial partnerships can have significant benefits for both parties and ultimately can serve to improve the scientific resources available to the core facility user base. The article will describe these types of arrangements and specifically highlight aspects of these agreements that can benefit each partner in addition to some specific challenges that can arise with 'branded' core facilities. [ABSTRACT FROM AUTHOR]

• The elastic instability phenomenon in hyperelastic layered materials with the phases exhibiting stiffening behavior is studied • A closed-form expression for the critical stretch of macroscopic instability is derived • An analytical prediction based on Bloch-Floquet analysis for the microscopic instability is exhibited • The critical parameters and transition of instability modes are found to be highly tunable with phase stiffening This paper investigates the elastic instability behavior in soft periodic laminates subjected to finite strains, with a focus on both macroscopic and microscopic instabilities. Considering the deformation-induced phase stiffening, the Gent model with a high bulk-to-shear modulus ratio describes the behavior of incompressible phases. This non-Gaussian statistics-based model captures the non-linear constitutive results from the limited extensibility of polymeric molecular chains. This paper derives an analytical prediction for the onset of macroscopic (or longwave) instability and microscopic instability as functions of material parameters. Moreover, a numerical Bloch-Floquet analysis is imposed on identifying the instability behavior under compression. We consider a wide range of phase combinations and find that the relatively rapid stiffening of the matrix compared to the stiff layer increases the stability of laminates by decreasing the critical stretch ratio. Essentially, properly manipulating the stiffening parameters can produce an absolutely stable region without observed instability. This paper also systematically illustrates the changes in instability and the transition between macro and micro instability in fully Gent laminates, which show higher stability than fully neo-Hookean laminates with larger critical stretch ratios. The critical characteristics of instabilities, such as critical stretch ratios and critical wavenumbers, can be controlled by the choice of stiffening parameters and other material properties, enlarging the tuning of soft laminates for desired buckling patterns in practical applications. [ABSTRACT FROM AUTHOR]

Aims: Evidence is accumulating of the therapeutic benefits of mesenchymal stromal cells (MSCs) in diabetes‐related conditions. We have identified a novel population of stromal cells within islets of Langerhans – islet stellate cells (ISCs) – which have a similar morphology to MSCs. In this study we characterize mouse ISCs and compare their morphology and function to MSCs to determine whether ISCs may also have therapeutic potential in diabetes. Methods: ISCs isolated from mouse islets were compared to mouse bone marrow MSCs by analysis of cell morphology; expression of cell‐surface markers and extracellular matrix (ECM) components; proliferation; apoptosis; paracrine activity; and differentiation into adipocytes, chondrocytes and osteocytes. We also assessed the effects of co‐culture with ISCs or MSCs on the insulin secretory capacity of islet beta cells. Results: Although morphological similar, ISCs were functionally distinct from MSCs. Thus, ISCs were less proliferative and more apoptotic; they had different expression levels of important paracrine factors; and they were less efficient at differentiation down multiple lineages. Co‐culture of mouse islets with ISCs enhanced glucose induced insulin secretion more effectively than co‐culture with MSCs. Conclusions: ISCs are a specific sub‐type of islet‐derived stromal cells that possess biological behaviors distinct from MSCs. The enhanced beneficial effects of ISCs on islet beta cell function suggests that they may offer a therapeutic target for enhancing beta cell functional survival in diabetes. [ABSTRACT FROM AUTHOR]

Nodular gill disease (NGD) is an emerging condition associated with amoeba trophozoites in freshwater salmonid farms. However, unambiguous identification of the pathogens still must be achieved. This study aimed to identify the amoeba species involved in periodic NGD outbreaks in two rainbow trout (Oncorhynchus mykiss) farms in Northeastern Italy. During four episodes (February–April 2023), 88 fish were euthanized, and their gills were evaluated by macroscopic, microscopic and histopathological examination. The macroscopic and microscopic severity of the lesions and the degree of amoebae infestation were scored and statistically evaluated. One gill arch from each animal was put on non‐nutrient agar (NNA) Petri dishes for amoeba isolation, cultivation and subsequent identification with SSU rDNA sequencing. Histopathology confirmed moderate to severe lesions consistent with NGD and mild to moderate amoeba infestation. The presence of amoebae was significantly correlated with lesion severity. Light microscopy of cultured amoebae strains and SSU rDNA analysis revealed the presence of a previously characterized amoeba Naegleria sp. strain GERK and several new strains: two strains from Hartmannelidae, three vannelid amoebae from the genus Ripella and cercozoan amoeba Rosculus. Despite the uncertainty in NGD etiopathogenesis and amoebae pathogenic role, identifying known and new amoebae leans towards a possible multi‐aetiological origin. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effect of four different strategies for bonding a CAD/CAM resin nanoceramic restoration (Lava Ultimate, 3M) to the dentin surface using a universal adhesive (Scotch Bond Universal, 3M) and adhesive resin cement (RelyX Ultimate, 3M) on the shear bond strength (SBS) and failure mode. The strategies comprised: (i) immediate sealing, immediate bonding; (ii) immediate sealing, bonding after 2 weeks with provisional restoration; (iii) immediate sealing with flowable resin composite reinforcement and bonding after 2 weeks with provisional restoration; and (iv) no immediate sealing, and bonding after 2 weeks with provisional restoration. After bonding, all the specimens were thermocycled, shear tests were performed using a universal testing machine, and failure modes were determined using stereomicroscope and scanning electron microscopy. The highest mean SBS was recorded with immediate sealing, immediate bonding strategy. Most adhesive failures with exposed dentinal tubules were noted in specimens exposed to bonding after 2 weeks with no immediate sealing, which was associated with the lowest SBS. Mixed failures predominated in all immediate dentin sealing groups. Immediate sealing with universal adhesives improves SBS, particularly in the single‐visit approach, which has shown significantly better performance, whereas the provisional phase has a negative effect. [ABSTRACT FROM AUTHOR]

Mitochondria are complex organelles with an outer membrane enveloping a second inner membrane that creates a vast matrix space partitioned by pockets or cristae that join the peripheral inner membrane with several thin junctions. Several micrometres long, mitochondria are generally close to 300 nm in diameter, with membrane layers separated by a few tens of nanometres. Ultrastructural data from electron microscopy revealed the structure of these mitochondria, while conventional optical microscopy revealed their extraordinary dynamics through fusion, fission, and migration processes but its limited resolution power restricted the possibility to go further. By overcoming the limits of light diffraction, Super-Resolution Microscopy (SRM) now offers the potential to establish the links between the ultrastructure and remodelling of mitochondrial membranes, leading to major advances in our understanding of mitochondria's structure-function. Here we review the contributions of SRM imaging to our understanding of the relationship between mitochondrial structure and function. What are the hopes for these new imaging approaches which are particularly important for mitochondrial pathologies? [ABSTRACT FROM AUTHOR]

Background: In polycrystal mechanics, determination of stress is associated with diffraction methods that measure (the inherently-related) elastic strain. Microscopic digital image correlation (DIC), while commanding much higher intragranular resolution, measures total strain, and its local accuracy is typically insufficient to evaluate elastic strain magnitudes. Objective: In situ DIC measurements over a partial unload of the polycrystal, where strains are virtually elastic, are explored for grain-averaged elastic strains and then, through a posed formalism, the stresses at the point of unload. Grain averaging is functionally employed to improve the DIC accuracy. The large objective is to emulate in situ complementary diffraction. Methods: Nickel with high elastic anisotropy is chosen. The utilized highly-automated instrument offers maximal resolution for DIC with optical microscopy over a gross grain field. Orientations are predetermined for the same grain layer via electron backscatter diffraction. High-accuracy grain masks are produced to isolate the strain fields of individual grains. Results: Very promising results are shown over a number of grains with sensible apparent compliance and stress values as well as linear unload behavior. Grains with sane results are largely predicted by a posed objectivity test that relies on DIC repeated with multiple reference loads. Conclusion: Though it will require extremely careful implementations of microscopic DIC with high intragranular resolution, the premise of measuring intergranular stress fields via partial unloads seems to be viable and worthy of further exploration and verification. This capability that is superposed over strain measurement offers a more stringent validation of high-fidelity crystal plasticity models. [ABSTRACT FROM AUTHOR]

This paper investigates the fatigue behaviour of laser powder bed fusion (LPBF) processed Ti6Al4V samples under three build orientations. The post-heat treatment (PHT-1050 °C) was carried out. The microstructural characterization was performed using optical microscopy, X-ray diffraction SEM and EDS techniques. The tensile test and high cycle fatigue tests were performed. The PHT performed at 1050 °C exhibited Widmanstatten microstructure consisting of a higher volume fraction of elongated β and a small amount of α. PHT samples' ductility was ~ 67%, 40% and 177% higher than the as-printed samples under horizontal, inclined and vertical orientations. Interestingly, the fatigue lives of PHT samples at higher stress levels were higher and nearly isotropic in all three build orientations than the as-printed samples due to enhanced ductility and fewer critical pores. Further strong correlation between PHT samples and ductility was established. Moreover, there was a marginal improvement in fatigue limit due to PHT at 1050 °C compared to as-printed samples. [ABSTRACT FROM AUTHOR]

To analyze the features of the epithelia coating neovaginas after vaginoplasty in women affected by Mayer-Rokitansky-Küster-Hauser syndrome We conducted a retrospective analysis of prospectively collected data. Women affected by Rokitansky syndrome who underwent neovaginal biopsy after vaginoplasty (McIndoe surgery, intestinal vaginoplasty, Vecchietti surgery, and Davydov surgery) were included. Macroscopic mucosal features were assessed through clinical examination and the Schilling test. Each biopsy specimen was prepared for examination by light microscopy and in some cases by scanning electron microscopy (SEM). Thirty-six patients (4 McIndoe, 2 intestinal vaginoplasty, 14 Vecchietti, and 16 Davydov) were included. All biopsies were performed without complications. In McIndoe's neovaginas, the mucosal microscopic features were similar to normal skin, with large areas of preserved epithelium, heterogeneous presence of dermal papillae, and superficial keratinization. The characteristics of the intestinal neovagina's surface were similar to those of a sigmoid colon, with well-shaped glands, cylindrical cells, and a secreting mucosa. In Vecchietti neovaginas, the surface the epithelium was flat and multilayered, highly similar to that of a normal vagina, with the presence of glycogen and superficial desquamation. On medium SEM magnification evaluation, the epithelium presented flattened polygonal cells. Finally, in Davydov neovaginas, none of the specimens had persistent mesothelial elements. The squamous neo-epithelium had regular aspects of differentiation with the presence of glycogen. At greater SEM magnification, microridges were evident, with a regular distribution. Each different technique of vaginoplasty leads to unique histological and structural features of the neovagina's mucosa. Knowledge of these elements must be the basis for the choice of the most appropriate intervention. [ABSTRACT FROM AUTHOR]

The atmospheric pressure plasma source HelixJet has been used to generate tungsten nanocrystals with narrow size distributions, well defined size control and with a considerably good particle yield. Tungsten particles are produced as the result of an evaporation process of a tungsten wire inserted on the middle axis of the jet after the wire is heated by interaction with the plasma. Temperature measurements using a thermocouple and by optical emission spectroscopy showed that, while the overall temperature of the wire is very high, it is not in the range of the melting temperature of tungsten; however, it can reach values needed for sublimation. Additionally, the wire is heated selectively while the temperature of the jet components reaches only a few hundred degrees Celsius. The particles cluster into agglomerates and their formation has been analyzed in relation to the reliability of a commercial scanning mobility particle sizer spectrometer. The dependence of the particle morphology and crystal structure on the plasma parameters such as power and gas flow was studied via transmission electron microscopy and the average size of the tungsten nanocrystals could be tuned between 12 and 25 nm. [ABSTRACT FROM AUTHOR]

Background: The restoration of cerebrovascular regulation and improvement of cerebral blood flow in ischaemic regions are crucial for improving the clinical prognosis after stroke. An-Gong-Niu-Huang-Wan (AGNHW) is a famous traditional compound Chinese medicine that has been used for over 220 years to treat acute ischaemic stroke; however, its role in the regulation of cerebral blood flow is still unclear. The aim of the present study was to investigate the regulatory effect of AGNHW on cerebral blood flow and microcirculation after ischaemic stroke and to elucidate the underlying mechanisms involved. Methods: Male C57BL/6 mice were subjected to distal middle cerebral artery occlusion (dMCAO) and randomly assigned to the sham, MCAO, or AGNHW groups. AGNHW was administered intragastrically 1 h after dMCAO. The rotarod test was utilized to evaluate behavioural function; TTC was used to determine the infarct volume; and ischaemic injury was assessed by detecting brain levels of SOD, MDA and NO. Then, cortical perfusion and acetazolamide-induced cerebrovascular reactivity were assessed using laser speckle contrast imaging, and the velocity and flux of red blood cells in cortical capillaries were detected using two-photon laser scanning microscopy. In addition, we employed RNA-Seq to identify variations in gene expression profiles and assessed endothelium-dependent changes in microcirculatory dysfunction by measuring vasoactive mediator levels. Results: AGNHW significantly increased cerebral blood flow, reduced the infarct volume, and promoted functional recovery after cerebral ischaemia. AGNHW increased the velocity and flux of red blood cells in capillaries and improved cerebrovascular reactivity in the ischaemic cortex. Furthermore, AGNHW regulated endothelium-dependent microcirculation, as evidenced by decreases in the expression of endothelins (Edn1, Edn3 and Ednrb) and the ratios of brain and serum TXB2/6-keto-PGF1α and ET-1/CGRP. Conclusions: AGNHW improved cerebral hypoperfusion, regulated cerebrovascular reactivity and attenuated microcirculatory dysfunction within the ischaemic cortex after stroke. This outstanding effect was achieved by modulating the expression of genes related to vascular endothelial cell function and regulating endothelium-dependent vasoactive mediators. [ABSTRACT FROM AUTHOR]

Cell plate formation during cytokinesis entails multiple stages occurring concurrently and requiring orchestrated vesicle delivery, membrane remodelling, and timely deposition of polysaccharides, such as callose. Understanding such a dynamic process requires dissection in time and space; this has been a major hurdle in studying cytokinesis. Using lattice light sheet microscopy (LLSM), we studied cell plate development in four dimensions, through the behavior of yellow fluorescent protein (YFP)-tagged cytokinesis-specific GTPase RABA2a vesicles. We monitored the entire duration of cell plate development, from its first emergence, with the aid of YFP–RABA2a, in both the presence and absence of cytokinetic callose. By developing a robust cytokinetic vesicle volume analysis pipeline, we identified distinct behavioral patterns, allowing the identification of three easily trackable cell plate developmental phases. Notably, the phase transition between phase I and phase II is striking, indicating a switch from membrane accumulation to the recycling of excess membrane material. We interrogated the role of callose using pharmacological inhibition with LLSM and electron microscopy. Loss of callose inhibited the phase transitions, establishing the critical role and timing of the polysaccharide deposition in cell plate expansion and maturation. This study exemplifies the power of combining LLSM with quantitative analysis to decode and untangle such a complex process. [ABSTRACT FROM AUTHOR]

We present Svetlana (SuperVised sEgmenTation cLAssifier for NapAri), an open-source Napari plugin dedicated to the manual or automatic classification of segmentation results. A few recent software tools have made it possible to automatically segment complex 2D and 3D objects such as cells in biology with unrivaled performance. However, the subsequent analysis of the results is oftentimes inaccessible to non-specialists. The Svetlana plugin aims at going one step further, by allowing end-users to label the segmented objects and to pick, train and run arbitrary neural network classifiers. The resulting network can then be used for the quantitative analysis of biophysical phenoma. We showcase its performance through challenging problems in 2D and 3D and provide a comprehensive discussion on its strengths and limits. [ABSTRACT FROM AUTHOR]

We employed polarization-sensitive nonlinear optical microscopy to assess crystallinity of diamond microneedles. In the experiment, we mapped the coherent anti-Stokes Raman spectroscopy (CARS) signal in the vicinity of 1332 cm−1 diamond Raman peak over the needle length and demonstrated that the third-order nonlinear optical susceptibility remains the same at both micrometer-sized base and the nanoscale thin apex of the needle. This indicated the single-crystal nature of the diamond needle and allowed us to describe the results of the polarization CARS measurements in terms of the third-order nonlinear susceptibility of diamond. High crystallinity of the needle was also confirmed by measuring the linewidth of the zero-phonon line of the silicon-vacancy centers in diamond. [ABSTRACT FROM AUTHOR]