Monitoring Of Dynamic Processes Research Articles

Unlocking Single Particle Anisotropy in Real‐Time for Photoelectrochemistry Processes at the Nanoscale

The key to rationally and rapidly designing high‐performance materials is the monitoring and comprehension of dynamic processes within individual particles in real‐time, particularly to gain insight into the anisotropy of nanoparticles. The intrinsic property of nanoparticles typically varies from one crystal facet to the next under realistic working conditions. Here, we introduce the operando collision electrochemistry to resolve the single silver nanoprisms (Ag NPs) anisotropy in photoelectrochemistry. We directly identify the effect of anisotropy on the plasmonic‐assisted electrochemistry at the single NP/electrolyte interface. The statistical collision frequency shows that heterogeneous diffusion coefficient among crystal facets facilitates Ag NPs to undergo direction‐dependent mass transfer toward the gold ultramicroelectrode. Subsequently, the current amplitudes of transient events indicate that anisotropy enables variations in dynamic interfacial electron transfer behaviors during photothermal processes. The results presented here demonstrate that the measurement precision of collision electrochemistry can be extended to the sub‐nanoparticle level, highlighting the potential for high‐throughput material screening with comprehensive kinetics information at the nanoscale.

Unlocking Single Particle Anisotropy in Real-Time for Photoelectrochemistry Processes at the Nanoscale.

The key to rationally and rapidly designing high-performance materials is the monitoring and comprehension of dynamic processes within individual particles in real-time, particularly to gain insight into the anisotropy of nanoparticles. The intrinsic property of nanoparticles typically varies from one crystal facet to the next under realistic working conditions. Here, we introduce the operando collision electrochemistry to resolve the single silver nanoprisms (Ag NPs) anisotropy in photoelectrochemistry. We directly identify the effect of anisotropy on the plasmonic-assisted electrochemistry at the single NP/electrolyte interface. The statistical collision frequency shows that heterogeneous diffusion coefficient among crystal facets facilitates Ag NPs to undergo direction-dependent mass transfer toward the gold ultramicroelectrode. Subsequently, the current amplitudes of transient events indicate that anisotropy enables variations in dynamic interfacial electron transfer behaviors during photothermal processes. The results presented here demonstrate that the measurement precision of collision electrochemistry can be extended to the sub-nanoparticle level, highlighting the potential for high-throughput material screening with comprehensive kinetics information at the nanoscale.

Dual‐Sensing Nanoreporter for Dynamic and High‐Throughput Monitoring of Immune Checkpoint Inhibitor Responses in Tumor‐Derived Organoids

AbstractHeterogenous immune responses to checkpoint blockade therapy remain a major challenge to early prediction of treatment efficacy. Current methods of evaluating treatment efficacy in tumors are ineffective in accurately monitoring the disease status after immunotherapy early on. This study reports an immune response monitoring strategy that longitudinally reports on two crucial protease activities involved in T cell‐mediated target cell death, granzyme B (GrzB) and downstream caspase 3 (Casp3), during and after immune checkpoint antibody treatment. Specifically, activatable nanoreporters are engineered to sensitively and selectively capture the activity of GrzB and Casp3 enzymes in tumor cells triggered by cytotoxic T cells in real‐time, providing a direct readout of the tumor response to immune checkpoint inhibitors (ICIs). Furthermore, incorporating 3D tumor‐derived organoids and ex vivo cultures on microfluidic devices with nanoreporters enables high‐throughput screening of various ICIs and their combinations in immunocompetent tumor models. These findings suggest that efficient monitoring of dynamic immunological processes in the tumor microenvironment could help uncover mechanisms associated with ICI response or resistance. It is further anticipated that combining the dual‐sensing nanoreporter with tumor‐derived organoid‐on‐chip technology could lead to an early prediction of treatment outcomes with high fidelity and accelerate the development of optimal treatment in immuno‐oncology.

Rapid online analysis of n-alkanes in gaseous streams via APCI mass spectrometry.

Online monitoring of dynamic chemical processes involving a wide volatility range of hydrocarbon species is challenging due to long chromatographic measurement times. Mass spectrometry (MS) overcomes chromatographic delays. However, the analysis of n-alkane mixtures by MS is difficult because many fragment ions are formed, which leads to overlapping signals of the homologous series. Atmospheric pressure chemical ionization (APCI) is suitable for the analysis of saturated hydrocarbons and is the subject of current research. Still, although APCI is a "soft ionization" technique, fragmentation is typically inevitable. Moreover, it is usually applied for liquid samples, while an application for online gas-phase monitoring is widely unexplored. Here, we present an automated APCI-MS method for an online gas-phase analysis of volatile and semi-volatile n-alkanes. Mass spectra for n-heptane and n-decane reveal [M-H]+, [M-3H]+ and [M-3H+H2O]+ as abundant ions. While [M-H]+ and [M-3H]+ show an excessive fragmentation pattern to smaller CnH2n+1+ and CnH2n-1+ cations, [M-3H+H2O]+ is the only relevant signal within the CnH2n+1O+ ion group, i.e., no chain cleavage is observed. This makes [M-3H+H2O]+ an analyte-specific ion that is suitable for the quantification of n-alkane mixtures. A calibration confirms the linearity of C7 and C10 signals up to concentrations of ~1000-1500 ppm. Moreover, validated concentration profiles are measured for a binary C7/C10 mixture and a five-alkane C7/C10/C12/C14/C20 mixture. Compared to the 40-min sampling interval of the reference gas chromatograph, MS sampling is performed within 5 min and allows dynamic changesto be monitored.

Sounding out the dynamics: a concise review of high-speed photoacoustic microscopy.

Photoacoustic microscopy (PAM) offers advantages in high-resolution and high-contrast imaging of biomedical chromophores. The speed of imaging is critical for leveraging these benefits in both preclinical and clinical settings. Ongoing technological innovations have substantially boosted PAM's imaging speed, enabling real-time monitoring of dynamic biological processes. This concise review synthesizes historical context and current advancements in high-speed PAM, with an emphasis on developments enabled by ultrafast lasers, scanning mechanisms, and advanced imaging processing methods. We examine cutting-edge innovations across multiple facets of PAM, including light sources, scanning and detection systems, and computational techniques and explore their representative applications in biomedical research. This work delineates the challenges that persist in achieving optimal high-speed PAM performance and forecasts its prospective impact on biomedical imaging. Recognizing the current limitations, breaking through the drawbacks, and adopting the optimal combination of each technology will lead to the realization of ultimate high-speed PAM for both fundamental research and clinical translation.

Possibility of Monitoring the Dynamic Impact of the Rolling Stock on the Track Superstructure Using Strain Gauges and Vibrometry

One of the priority tasks in development of railway transport is to raise its efficiency by increasing the time between repairs for both the track superstructure and the rolling stock. Solving this problem is impossible without timely, complete, and reliable information about the dynamics of interaction of the rolling stock with the infrastructure. To organise monitoring of dynamic processes, completely different types of primary transducers are used: resistance strain gauges, fibre-optic sensors, dynamometers (force sensor pads), accelerometers, acoustic emission sensors. This implies relevance of the scientific and technical problem of comparative testing of sensors of different types to assess the information content of their signals and justify the criteria for choosing primary transducers when solving specific monitoring problems.The objective of the study is to comparatively test removable resistive strain sensors, optical polarisation strain sensors and accelerometers under a passing train and to evaluate their information content to control rail depression and detect defects on the running surface of wagon wheels.The study using finite element modelling and a physical model of a rail as of a beam on an elastic foundation, substantiates the relationship between longitudinal deformations and vertical accelerations of the rail foot. Comparative tests of removable strain-resistive and optical polarisation strain sensors and accelerometers were held on an experimental section of track under a passing train. A signal processing algorithm has been developed and the equivalence of strain gauges and vibrometers for determining the depression of a rail under a passing train has been proven. Acomparison has been made of the pulse components of the signals of deformation and vibration acceleration during movement of a wheel with a defect on the running surface, and the requirements for the frequency characteristics of the sensors and their mounting on the rail surface have been substantiated.

AI-designed RF pulses enable fast pulsing heteronuclear multiple quantum coherence NMR experiment at high and ultra-high magnetic fields.

We present a new AI-optimized 2D heteronuclear multiple quantum coherence (RAPID-HMQC) pulse sequence for NMR spectroscopy. RAPID-HMQC is a longitudinal 1H relaxation-optimized experiment with new AI-designed band-selective pulses to accelerate the analysis of organic compounds, metabolites, biopolymers, and real-time monitoring of dynamic processes at high- and ultra-high magnetic fields.

Diagnostics of Atmospheric Plasma Jets of Helium and Argon Barrier Discharge in a Cylindrical Microwave Cavity Resonator

Introduction. Technologies related to the use of low-temperature atmospheric plasmas are developing at a rapid pace. Creation of new low-temperature plasma sources for specific applications requires monitoring of dynamic processes in such discharges with a high time resolution. Electron concentration is one the most important plasma characteristics, which can be very low for a low-temperature atmospheric pressure plasma. However, the methods currently available for diagnostics of gas-discharge plasmas are either characterized by insufficient sensitivity or unable to monitor dynamic processes in non-stationary discharges. In this regard, the development of new diagnostic approaches to low-temperature atmospheric plasma seems to be a relevant research direction.Aim. To develop a diagnostic method for an atmospheric plasma with a low gas temperature and a low electron concentration in a cylindrical microwave resonator.Materials and methods. The proposed diagnostic method is based on the well-known principle of measuring the frequency shift and the Q-factor of the eigenmodes of the microwave resonator, inside which the plasma under study is located.Results. Measurements of the atmospheric barrier discharge plasma jets in a helium and argon stream in a cylindrical microwave resonator were performed. The proposed geometry made it possible to significantly increase the sensitivity of measurements. It became possible to exclude the effect of polarization degeneracy in a round cylindrical resonator. The developed system was also tested on test objects with a known value of permittivity.Conclusion. A method for microwave diagnostics of stationary and non-stationary cold atmospheric plasma jets in a cylindrical resonator, inside which transmitting and receiving antennas are installed, as well as an orthogonal thin conductor preventing the excitation of undesirable modes, was developed.

Real‐Time Monitoring of Dynamic Chemical Processes in Microbial Metabolism with Optical Sensors

AbstractMonitoring microbial metabolism is vital for revealing the mechanism of disease related to microbial metabolism and providing guidance for biomanufacturing processes optimization. However, it remains a grand challenge to offer real‐time insights into microbial metabolism owing to the complex and dynamic process. In this paper, the recent advances and prospects of optical biosensors including the organic, genetic coding and inorganic optical biosensors are briefly described for real‐time monitoring of dynamic microbial metabolism. This paper points out that challenges remain in microbial heterogeneity. We believe that this work will inspire the application of developing new methods for single cell real‐time analysis.

Global environmental systems – multivariate anthropoecological classification

ABSTRACT Changes to the Earth's environment, increasing anthropogenic pressure, and the global decline of biodiversity bring the need to establish spatial frameworks for the monitoring and assessment of such dynamic processes. Several environmental stratifications have been developed at the global level; however, most of them only include natural conditions in the classification process. Incorporating spatial patterns of biodiversity and the degree of anthropogenic pressure seems to be essential in an era of significant environmental transformation. We developed a new comprehensive classification of Global Environmental Systems based on general abiotic gradients, distribution of biodiversity, and spatial differentiation of human impact. This classification is based on 22 variables covering abiotic, biotic, and anthropogenic factors. We identified 10 abiotic, biotic, and anthropogenic classes using cluster analysis; their combination results in 169 unique Global Environmental Systems (GES) showing human-environment interactions. Each class shows an area with similar abiotic and biotic background and human pressure..

Algorytmy konstrukcji obrazów w systemach tomografii procesowej

Tomography is one of the methods used to obtain cross-sectional images of the analysed object. This imaging technique has been used for many years in medicine, providing significantly higher efficiency of patient’s diagnosis. In recent years, the imaging method has also found application for visualization of industrial processes. The article describes the tomographic image construction methods used in the modules of monitoring of dynamic industrial processes. Introduction to methods of the inverse problems solutions in tomography systems, from a practical point of view, was presented, with particular emphasis on the electrical capacitance tomography. It was shown how based on the mathematical theorems and knowledge about physics rules, concerning the behaviour of measurement signal in tomography sensor, is possible to construct cross-sectional image of industrial process. In article the image construction steps were explained and discussion on the impact of various factors on the quality and speed of imaging was conducted.

A mid-infrared lab-on-a-chip for dynamic reaction monitoring

Mid-infrared spectroscopy is a sensitive and selective technique for probing molecules in the gas or liquid phase. Investigating chemical reactions in bio-medical applications such as drug production is recently gaining particular interest. However, monitoring dynamic processes in liquids is commonly limited to bulky systems and thus requires time-consuming offline analytics. In this work, we show a next-generation, fully-integrated and robust chip-scale sensor for online measurements of molecule dynamics in a liquid solution. Our fingertip-sized device utilizes quantum cascade technology, combining the emitter, sensing section and detector on a single chip. This enables real-time measurements probing only microliter amounts of analyte in an in situ configuration. We demonstrate time-resolved device operation by analyzing temperature-induced conformational changes of the model protein bovine serum albumin in heavy water. Quantitative measurements reveal excellent performance characteristics in terms of sensor linearity, wide coverage of concentrations, extending from 0.075 mg ml−1 to 92 mg ml−1 and a 55-times higher absorbance than state-of-the-art bulky and offline reference systems.

Using Graphene Field-Effect Transistors for Real-Time Monitoring of Dynamic Processes at Sensing Interfaces. Benchmarking Performance against Surface Plasmon Resonance

Using Graphene Field-Effect Transistors for Real-Time Monitoring of Dynamic Processes at Sensing Interfaces. Benchmarking Performance against Surface Plasmon Resonance

MOLISENS: MObile LIdar SENsor System to exploit the potential of small industrial lidar devices for geoscientific applications

Abstract. We propose a newly developed modular MObile LIdar SENsor System (MOLISENS) to enable new applications for small industrial lidar (light detection and ranging) sensors. The stand-alone modular setup supports both monitoring of dynamic processes and mobile mapping applications based on SLAM (Simultaneous Localization and Mapping) algorithms. The main objective of MOLISENS is to exploit newly emerging perception sensor technologies developed for the automotive industry for geoscientific applications. However, MOLISENS can also be used for other application areas, such as 3D mapping of buildings or vehicle-independent data collection for sensor performance assessment and sensor modeling. Compared to TLSs, small industrial lidar sensors provide advantages in terms of size (on the order of 10 cm), weight (on the order of 1 kg or less), price (typically between EUR 5000 and 10 000), robustness (typical protection class of IP68), frame rates (typically 10–20 Hz), and eye safety class (typically 1). For these reasons, small industrial lidar systems can provide a very useful complement to currently used TLS (terrestrial laser scanner) systems that have their strengths in range and accuracy performance. The MOLISENS hardware setup consists of a sensor unit, a data logger, and a battery pack to support stand-alone and mobile applications. The sensor unit includes the small industrial lidar Ouster OS1-64 Gen1, a ublox multi-band active GNSS (Global Navigation Satellite System) with the possibility for RTK (real-time kinematic), and a nine-axis Xsens IMU (inertial measurement unit). Special emphasis was put on the robustness of the individual components of MOLISENS to support operations in rough field and adverse weather conditions. The sensor unit has a standard tripod thread for easy mounting on various platforms. The current setup of MOLISENS has a horizontal field of view of 360∘, a vertical field of view with a 45∘ opening angle, a range of 120 m, a spatial resolution of a few centimeters, and a temporal resolution of 10–20 Hz. To evaluate the performance of MOLISENS, we present a comparison between the integrated small industrial lidar Ouster OS1-64 and the state-of-the-art high-accuracy and high-precision TLS Riegl VZ-6000 in a set of controlled experimental setups. We then apply the small industrial lidar Ouster OS1-64 in several real-world settings. The mobile mapping application of MOLISENS has been tested under various conditions, and results are shown from two surveys in the Lurgrotte cave system in Austria and a glacier cave in Longyearbreen on Svalbard.

Monitoring of the Sound Velocity Variation In Rat Muscle and a Novel Approach to Quantify Muscle Injury

Detection of the degree of skeletal muscle injury is of utmost importance in medical treatment and rehabilitation. Ultrasound and magnetic resonance imaging are now been using to assess muscle injuries. Presented is the custom-built ultrasonic detection scheme that has been implemented to detect the degrees of muscle injuries. The changes in the velocity of ultrasound in muscle due to artificially administered injuries have been detected and compared. The purpose of this study is to present a novel high-resolution ultrasonic detection scheme in the field of skeletal muscle injury detection and research. To detect variations of the velocity of sound, the expansion of the muscle is suppressed by mechanical clamping. Under this condition, any variation in the time-of-flight of the ultrasonic signals can only be introduced by a variation of the velocity of sound along the path of the ultrasound transit signal. Opposite to the general behavior of healthy muscle, the injured muscle shows comparatively an increase in the time-of-flight, relating to a decrease in the sound velocity, with the levels of injuries. Since injured muscle increases the travel time of ultrasonic signal, the influence of artificial injury on the monitored muscle can be detected and quantified with the comparison measurements between healthy and injured muscle. The diminishing velocity value with the level of injuries is detected and quantified in this study. The observed rate of change in sound velocity and force for contraction and relaxation phases, for different activation frequencies, are found to be deteriorated with the degrees of injuries. The achieved resolution of the velocity of (longitudinally polarized) ultrasound in rat muscle is about 0.01% relating to the measurement on relaxed muscle by comparison to the well-known velocity of water. A resolution in time resolved measurements of about 0.01% is reached for each individual measurement, performed at a repetition rate of 50 M measurements per second, during monitoring of dynamic processes for the actual velocity of ultrasound traveling in the observed rat’s GM muscle.

Dynamic Disease Screening by Joint Modelling of Survival and Longitudinal Data

AbstractSequential monitoring of dynamic processes is an active research area because of its broad applications in different industries and scientific research projects, including disease screening in medical research. In the literature, it has been shown that dynamic screening system (DySS) is a powerful tool for sequential monitoring of dynamic processes. To detect a disease (e.g. stroke) for a patient, existing DySS methods first estimate the regular longitudinal pattern of certain disease predictors (e.g. blood pressure, cholesterol level) from an in-control (IC) dataset that contains observations of a group of non-diseased people, and then compare the longitudinal pattern of the observed disease predictors of the given patient with the estimated regular longitudinal pattern. A signal of disease occurrence is triggered if their cumulative difference exceeds a certain level, facilitated by a built-in control chart. In practice, a dataset containing longitudinal observations of the disease predictors of both non-diseased and diseased people is often available in advance, from which it is possible to explore the relationship between the disease occurrence and the longitudinal pattern of the disease predictors. This relationship should be helpful for disease screening. In this paper, a new DySS method is suggested based on this idea. Numerical studies confirm that it can improve the existing DySS methods for disease screening.

Monitoring Catalytic 2-Propanol Oxidation over Co3O4 Nanowires via In Situ Photoluminescence Spectroscopy.

Spectroscopic methods enabling real-time monitoring of dynamic surface processes are a prerequisite for identifying how a catalyst triggers a chemical reaction. We present an in situ photoluminescence spectroscopy approach for probing the thermocatalytic 2-propanol oxidation over mesostructured Co3O4 nanowires. Under oxidative conditions, a distinct blue emission at ∼420 nm is detected that increases with temperature up to 280 °C, with an intermediate maximum at 150 °C. Catalytic data gained under comparable conditions show that this course of photoluminescence intensity precisely follows the conversion of 2-propanol and the production of acetone. The blue emission is assigned to the radiative recombination of unbound acetone molecules, the n ↔ π* transition of which is selectively excited by a wavelength of 270 nm. These findings open a pathway for studying thermocatalytic processes via in situ photoluminescence spectroscopy, thereby gaining information about the performance of the catalyst and the formation of intermediate products.

Shining Light on Protein Kinase Biomarkers with Fluorescent Peptide Biosensors.

Protein kinases (PKs) are established gameplayers in biological signalling pathways, and a large body of evidence points to their dysregulation in diseases, in particular cancer, where rewiring of PK networks occurs frequently. Fluorescent biosensors constitute attractive tools for probing biomolecules and monitoring dynamic processes in complex samples. A wide variety of genetically encoded and synthetic biosensors have been tailored to report on PK activities over the last decade, enabling interrogation of their function and insight into their behaviour in physiopathological settings. These optical tools can further be used to highlight enzymatic alterations associated with the disease, thereby providing precious functional information which cannot be obtained through conventional genetic, transcriptomic or proteomic approaches. This review focuses on fluorescent peptide biosensors, recent developments and strategies that make them attractive tools to profile PK activities for biomedical and diagnostic purposes, as well as insights into the challenges and opportunities brought by this unique toolbox of chemical probes.

Hardware-In-The-Loop Assessment of Fuzzy and Neural Network Fault Diagnosis Schemes for a Wind Turbine Model

The fault diagnosis of wind turbines includes extremely challenging aspects that motivate the research issues considered in this paper. In particular, this work studies fault diagnosis solutions that are considered in a viable way and used as advanced techniques for condition monitoring of dynamic processes. To this end, the work proposes the design of fault diagnosis techniques that exploits the estimation of the fault by means of data-driven approaches. These fuzzy and neural network structures are integrated with auto-regressive with exogenous input regressors, thus making them able to approximate unknown nonlinear dynamic functions with arbitrary degree of accuracy. The capabilities of fault diagnosis schemes are validated by using a real-time simulator of a wind turbine system. Moreover, at this stage the benchmark is also useful to analyse the robustness and the reliability characteristics of the developed tools in the presence of model-reality mismatch and modelling error effects featured by the wind turbine simulator. This realistic simulator relies on a hardware-in-the-loop tool that is finally implemented for verifying and validating the performance of the developed fault diagnosis strategies in an actual environment.

Simultaneous Infrared Spectroscopy, Raman Spectroscopy, and Luminescence Sensing: A Multispectroscopic Analytical Platform.

Scientific questions in fields such as catalysis, monitoring of biological processes, or environmental chemistry demand analytical technologies combining orthogonal spectroscopies. Combined spectroscopic concepts facilitate in situ online monitoring of dynamic processes providing a better understanding of the involved reaction pathways. In the present study, a low-liquid-volume multispectroscopic platform was developed based on infrared attenuated total reflection (IR-ATR) spectroscopy combined with Raman spectroscopy and luminescence sensing. To demonstrate the measurement capabilities, exemplary analyte systems including water/heavy water and aqueous solutions of ammonium sulfate were analyzed as proof-of-principle studies. It was successfully demonstrated that three optical techniques may be integrated into a single analytical platform without interference providing synchronized and complementary data sets by probing the same minute sample volume. In addition, the developed assembly provides a gastight lid sealing the headspace above the probed liquid for monitoring the concentration of molecular oxygen also in the gas phase via luminescence quenching. Hence, the entire assembly may be operated at inert conditions, as required, for example, during the analysis of photocatalytic processes.