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The counting process has abundant applications in reality, and Poisson process monitoring actually has received extensive attention and research. However, conventional methods experience poor performance when shifts appears early and only small number of historical observations in Phase I can be used for estimation. To overcome it, we creatively propose a new online monitoring algorithm under the transfer learning framework, which utilizes the information from observations of additional data sources so that the target process can be described better. By making the utmost of the somewhat correlated data from other domains, which is measured by a bivariate Gamma distributed statistic presented by us, the explicit properties (e.g., posterior probability mass function, posterior expectation, and posterior variance) are also strictly proved. Furthermore, based on the above theoretical results, we design two computationally efficient control schemes in Phase II, that is a control chart based on the cumulative distribution function for large shifts and an exponentially weighted moving average control chart for small shifts. For a better understanding of the more practical applications and transferability matter, we provide some optimal values for parameter setting. Extensive numerical simulations and a case of skin cancer incidence in America verify the superiorities of our approach. [ABSTRACT FROM AUTHOR]

Cell line generation of mammalian cells is a time‐consuming and labor‐intensive process, especially because of challenges in clone selection after transfection. Antibiotics are common selection agents for mammalian cells due to their simplicity of use. However, the optimal antibiotic concentration must be determined with a kill curve experiment before clone selection starts. The traditional kill curve experiments are resource‐intensive and time‐consuming due to necessary sampling and offline analysis effort. This study, thus, explores the potential of online monitoring the oxygen transfer rate (OTR), as a non‐invasive and efficient alternative for kill curve experiments. The OTR is monitored using the Transfer‐rate Online Measurement (TOM) system and the micro(μ)‐scale Transfer‐rate Online Measurement (μTOM) device, which was used for mammalian cells first. It could be shown that the OTR curves for both devices align perfectly, affirming consistent cultivation conditions. The μTOM device proves effective in performing kill curve experiments in 96‐deep‐well plates without the need for sampling and offline analysis. The streamlined approach reduces medium consumption by 95%, offering a cost‐effective and time‐efficient solution for kill curve experiments. The study validates the generalizability of the method by applying it to two different CHO cell lines (CHO‐K1 and sciCHO) with two antibiotics (puromycin and hygromycin B) each. In conclusion, the broad application of OTR online monitoring for CHO cell cultures in 96‐deep‐well plates is highlighted. The μTOM device proves as a valuable tool for high‐throughput experiments, paving the way for diverse applications, such as media and clone screening, cytotoxicity tests, and scale‐up experiments. [ABSTRACT FROM AUTHOR]

Plasma fluctuations, the uncertainty of laser ablation, and bremsstrahlung limit the identification of online element analysis during laser processing and cause difficulty in achieving concentration results with sufficient accuracy and repeatability. A laser‐induced breakdown spectroscopy (LIBS) online monitoring system with plasma spatial filtering and spectral screening is proposed to solve this problem. In this system, the high‐frequency ablation noise component of the plasma is eliminated using a specially designed optical Fourier filtering structure, and a spectral screening system based on plasma time waveform monitoring is used to suppress the influence of plasma fluctuations. Without noise filters or algorithm optimizations and based only on the basic internal standard method, the calibration curves of all nine elements in the alloy sample exhibits a Pearson's R2 value ranged from 0.91 to 0.99, with a mean of 0.94. The relative standard deviations are all in the range of 3.5%–8.4% with a mean of 5.4%. The accuracy and repeatability are comparable to those of typical LIBS systems. [ABSTRACT FROM AUTHOR]

In this study, we introduce an online monitoring procedure designed to sequentially detect change points in the conditional quantiles of location‐scale time series models. This statistical process control issue holds great significance in risk management, particularly in measuring the value‐at‐risk or expected shortfall of financial assets. Our approach employs suitable detectors, including cumulative sum statistics. We then define a stopping rule and determine control limits based on asymptotic theorems to signal an anomaly. To further evaluate the proposed methods, we conduct a comprehensive empirical study analyzing various aspects of our monitoring procedures when applied to location‐scale time series models. Additionally, we perform a real data analysis using the daily returns of the Korea Composite Stock Price Index (KOSPI) and EuroStoxx 50 indices to affirm the adequacy of the proposed monitoring procedures in real‐world applications. [ABSTRACT FROM AUTHOR]

The statistical anionic copolymerization of 4‐trimethylsilylstyrene (TMSS) with isoprene (I) in cyclohexane was investigated using in situ near‐infrared (NIR) spectroscopy in the presence of various amounts of the polar modifier tetrahydrofuran (THF). Polymers with narrow molecular weight distribution of 85–138 kg/mol and dispersities of 1.09–1.22 were obtained. By increasing modifier content, the reactivity ratios can be adjusted over a wide range from rTMSS < rI to rTMSS >> rI. Compared to the system styrene/isoprene (S/I) only a minute amount of modifier (0.5 eq THF relative to lithium) is sufficient to alter the reactivity ratios, resulting in an ideally random copolymerization, which validates the higher reactivity of TMSS compared to styrene. Using these reactivity ratios, molar and volume composition gradients were calculated. Additionally, the glass transition temperature and microstructure of the polyisoprene units were investigated via differential scanning calorimetry and proton nuclear magnetic resonance. The results are encouraging for the use of these materials in high‐end applications like membranes. [ABSTRACT FROM AUTHOR]

Costly complex media components such as yeast extract and peptone are still widely used in industrial bioprocesses, despite their ill‐defined composition. Side stream products such as corn steep liquor (CSL) present a compelling economical alternative that contains valuable nutrients required for microbial growth, that is, nitrogen and amino acids, but also vitamins, trace elements, and other minerals. However, as a side stream product, CSL may be subject to batch‐to‐batch variations and compositional heterogeneity. In this study, the Respiration Activity MOnitoring System designed for shake flasks (RAMOS) and 96‐well microtiter plates (μTOM) were applied to investigate the potential and constraints of CSL utilization for two model microorganisms: E. coli and B. subtilis. Considering the dry substance content of complex nutrients involved, CSL‐based media are more efficient in biomass production than the common lysogeny broth (LB) medium, containing 5 g/L yeast extract, 10 g/L peptone, and 5 g/L NaCl. At a glucose to CSL (glucose/CSL, g/g) ratio of 1/1 (g/g) and 2/1 (g/g), a secondary substrate limitation occurred in E. coli and B. subtilis cultivations, respectively. The study sheds light on differences in the metabolic activity of the two applied model organisms between varying CSL batches, which relate to CSL origin and production process, as well as the effect of targeted nutrient supplementation. Through a targeted nutrient supplementation, the most limiting component of the CSL‐glucose medium used for these applied model microorganisms was identified to be ammonium nitrogen. This study proves the suitability of CSL as an alternative nutrient source for E. coli and B. subtilis. The RAMOS and μTOM technique detected differences between CSL batches, allowing easy and early identification of varying batches. A consistent performance of the CSL batches in E. coli and B. subtilis cultivations was demonstrated. [ABSTRACT FROM AUTHOR]

The goal of microphysiological systems (MPS) is to replicate the relevant functionality of human organ tissues in in vitro. MPS technology so far has been used to simulate the various human organs and with the help of sensor integration in the MPS systems the biological activities of the organ to be modeled have been translated into data to be analyzed for further considerations. Most standard characterization approaches are intrusive and detrimental, and not feasible for online monitoring of cell cultures. Microfluidic biosensors, for instant, provide non‐invasive on‐line detection of biomarkers and molecules under targeted indicators with a high detection extent, successfully overcoming the limits of existing approaches. Microfluidic biosensors are rapidly being incorporated into MPS and employed for real‐time target identification as a result. In this review the focus is on emerging ways for miniaturizing and embedding biosensing systems in MPS also known as "organ‐on‐chip". Cutting‐edge microfluidic biosensors are also covered with examples, showing their key benefits in monitoring MPS and highlighting current breakthroughs, before describing the remaining problems and anticipated future improvements in integrated microfluidic biosensors. [ABSTRACT FROM AUTHOR]

Online fluorescence monitoring has become a key technology in modern bioprocess development, as it provides in‐depth process knowledge at comparably low costs. In particular, the technology is widely established for high‐throughput microbioreactor cultivation systems, due to its noninvasive character. For microtiter plates, previously also multi‐wavelength 2D fluorescence monitoring was developed. To overcome an observed limitation of fluorescence sensitivity, this study presents a modified spectroscopic setup, including a tunable emission monochromator. The new optical component enables the separation of the scattered and fluorescent light measurements, which allows for the adjustment of integration times of the charge‐coupled device detector. The resulting increased fluorescence sensitivity positively affected the performance of principal component analysis for spectral data of Escherichia coli batch cultivation experiments with varying sorbitol concentration supplementation. In direct comparison with spectral data recorded at short integration times, more biologically consistent signal dynamics were calculated. Furthermore, during partial least square regression for E. coli cultivation experiments with varying glucose concentrations, improved modeling performance was observed. Especially, for the growth‐uncoupled acetate concentration, a considerable improvement of the root‐mean‐square error from 0.25 to 0.17 g/L was achieved. In conclusion, the modified setup represents another important step in advancing 2D fluorescence monitoring in microtiter plates. [ABSTRACT FROM AUTHOR]

In the field of bioprocess development miniaturization, parallelization and flexibility play a key role reducing costs and time. To precisely meet these requirements, additive manufacturing (3D‐printing) is an ideal technology. 3D‐printing enables rapid prototyping and cost‐effective fabrication of individually designed devices with complex geometries on demand. For successful bioprocess development, monitoring of process‐relevant parameters, such as pH, dissolved oxygen (DO), and biomass, is crucial. Online monitoring is preferred as offline sampling is time‐consuming and leads to loss of information. In this study, 3D‐printed cultivation vessels with optical prisms are evaluated for the use in upstream processes of different industrially relevant microorganisms and cell lines. It was shown, that the 3D‐printed optically modified well (OMW) is of benefit for a wide range of biotechnologically relevant microorganisms and even for mammalian suspension cells. Evaluation tests with Escherichia coli, Bacillus subtilis, Saccharomyces cerevisiae, and Chinese hamster ovary (CHO) cells were performed, providing highly reproducible results. Growth behavior of OMW cultures was comparable to behavior of shake flask (SF) cultivations and the signal to noise ratio in online biomass measurement was shown to be reduced up to 95.8% by using the OMW. Especially the cultivation phases with low turbidity respective optical densities below 1.0 rel.AU could be monitored accurately for the first time. Furthermore, it was demonstrated that the 3D‐printed optics are transferable to different well geometries and sizes, enabling efficient biomass monitoring for individual requirements with tailor‐made 3D‐printed cultivation vessels in small scale. [ABSTRACT FROM AUTHOR]

Hot metal desulfurization is the main process step for removing sulfur in blast furnace‐based steelmaking. A desulfurization reagent is pneumatically injected into the hot metal through a submerged lance causing it to vibrate. The aim of this study is to develop a mechanical vibration measurement‐based method that can detect changes in the gas‐forming properties of the reagent. The detection is performed using Elastic Net regression and eXtreme Gradient Boosting‐based classification models the classification performance of which is compared. The lance aging causes changes in its dynamic characteristics, and the disturbing effect of this is removed from the measured data of the lance vibration prior to classification by means of a developed cleaning algorithm. The best classification performance in detecting changes in the gas‐forming properties, with an area under the receiver operating characteristic curve of 0.916 and Matthews correlation coefficient of 0.699, is achieved using an Elastic Net regression‐based classification model. The results of this work serve as a basis for developing industrial applications in which the effective utilization of the excitation, such as vibrations generated by the gas formation can be utilized for process monitoring and as a soft sensor for predicting the reagent‐induced process variance. [ABSTRACT FROM AUTHOR]

Much effort has been done toward the development of new emulsifiers able to improve the latex stability. In this sense, ionic liquids based on imidazolium constitute a new category of stabilizer in study. Moreover, the near infrared (NIR) spectroscopy has been extensively investigated as a tool to follow the properties of polymerization reactions. In this study different ionic liquids are investigated as emulsifiers during the emulsion homopolymerization of the styrene and methyl methacrylate. A quantitative analysis method is developed to determine the properties of latex based on the joint use of the NIR spectra and partial least squares regression (PLS). Kinetic results indicate that the latex properties are greatly influenced by the type of ionic liquid. The current work shows that the NIR spectrophotometer can be successfully used for monitoring of the latex properties, enabling to track the polymerization dynamics even in the presence of ionic liquids. [ABSTRACT FROM AUTHOR]

In the manufacture of therapeutic monoclonal antibodies, the clarified cell culture fluid (CCF) is typically loaded onto an initial protein A affinity capture column. Imperfect mass transfer and loading to maximum capacity can risk antibody breakthrough and loss of valuable product, but conservative underloading wastes expensive protein A resin. In addition, the effects of column fouling and ligand degradation require the frequent optimization of immunoglobulin G (IgG) loading to avoid wastage. Continuous real‐time monitoring of IgG flowthrough is of great interest, therefore. We previously developed a fluorescence‐based monitoring technology that allows batch mix‐and‐read mAb detection in the CCF. Here, we report the use of reporters immobilized on cyanogenbromide‐activated Sepharose 4B resin for continuous detection of IgG in column breakthrough. The column effluent is continuously contacted with immobilized fluorescein‐labeled Fc‐binding ligands in a small monitoring column to produce an immediately‐detectable change in fluorescence intensity. The technology allows rapid and reliable monitoring of IgG in a flowing stream of clarified CCF emerging from a protein A column, without prior sample preparation. We observed a significant change in fluorescence intensity at 0.5 g/L human IgG, sufficient to detect a 5% breakthrough of a 10 g/L load, within 18 s at a flow rate of 0.5 ml/min. The current small‐scale technology is suitable for use in process development, but the chemistry should be readily adaptable to larger scale applications using fiber‐optic sensors, and continuous IgG monitoring could be applicable in a variety of upstream and downstream process settings. [ABSTRACT FROM AUTHOR]

Streptomyces species are intensively studied for their ability to produce a variety of natural products. However, conditions influencing and leading to product formation are often not completely recognized. Therefore, in this study, high‐throughput online monitoring is presented as a powerful tool to gain in‐depth understanding of the cultivation of the model organism Streptomyces coelicolor A3(2). Through online measurements of oxygen transfer rate and autofluorescence, valuable information about availability of nutrients and product formation patterns of the pigments actinorhodin and undecylprodigiosin can be obtained and explained. Therefore, it is possible to determine the onset of pigmentation and to study in detail the influencing factors thereof. One factor identified in this study is the filling volume of the cultivation vessel. Slight variations led to varying pigmentation levels. By combining optical and metabolic online monitoring techniques, the correlation of the filling volume with pigmentation could be explained as a result of different growth trajectories caused by varying specific power inputs and their influence on the pellet formation of the filamentous system. Finally, experiments with the addition of supernatant from unpigmented and pigmented cultures could highlight the applicability of the presented approach to study quorum sensing and cell‐cell interaction. [ABSTRACT FROM AUTHOR]

Online monitoring by flow NMR spectroscopy is a powerful approach to study chemical reactions and processes, which can provide mechanistic understanding, and drive optimisations. However, some of the most useful methods for mixture analysis and reaction monitoring are not directly applicable in flow conditions. This is the case of classic diffusion‐ordered NMR spectroscopy (DOSY) methods, which can be used to separate the spectral information for mixture's components. We describe a fast and flow‐compatible diffusion NMR experiment that makes it possible to collect accurate diffusion data for samples flowing at up to 3 mL/min. We use it to monitor the synthesis of a Schiff base with a flow‐tube with a time resolution of approximately 2 minutes. The one‐shot flow‐compatible diffusion NMR described here open many avenues for reaction monitoring applications. [ABSTRACT FROM AUTHOR]

The red pigment prodigiosin is of high pharmaceutical interest, due to its potential applications as an antitumor drug and antibiotic agent. As previously demonstrated, Pseudomonas putida KT2440 is a suitable host for prodigiosin production, as it exhibits high tolerance toward the antimicrobial properties of prodigiosin. So far, prodigiosin concentrations of up to 94 mg/L have been achieved in shake flask cultivations. For the characterization and optimization of the prodigiosin production process, the scattered light of P. putida and fluorescence of prodigiosin was measured. The excitation and emission wavelengths for prodigiosin measurement were analyzed by recording 2D fluorescence spectra. The strongest prodigiosin fluorescence was obtained at a wavelength combination of 535/560 nm. By reducing the temperature to 18 °C and using 16 g/L glucose, the prodigiosin concentration was more than doubled compared with the initial cultivation conditions. The obtained results demonstrate the capabilities of parallelized microscale cultivations combined with noninvasive online monitoring of fluorescence for rapid bioprocess development, using prodigiosin as a molecule of current biotechnological interest. [ABSTRACT FROM AUTHOR]

Temperature is one of the most common indicators for the health of electrical equipment in the substation. By now, infrared thermography has been an important monitoring tool due to its real‐time temperature measurement and noncontact manner. However, at present, portable thermal imagers are usually used to collect and store the status image of single equipment at a certain time, which cannot continuously track the condition of the equipment and the efficiency is very low. In order to solve this problem, our team proposed a method for online condition of electrical equipment based on the visualization and processing of infrared image temperature data. We developed video inspection software, equipped with an infrared camera for automatic inspection to obtain infrared images. After that, the target equipment in a whole image are automatically extracted based on the reference image and the equipment type of each target is classified. Then, in order to visualize temperature data and extract temperature information for different types of equipment, the concepts of heating spot, heating section, and heating area are defined. Finally, diagnosis rules based on relevant related thermal fault diagnosis standards and past experience are proposed to evaluate the condition of each target equipment, using the temperature rise and heat generation percentage. The method has been applied in a real substation and proved its effectiveness. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

This study presents a new neural network approach to identify the presence and type of obstruction in pipes from measurements of passive acoustic emissions. Inserts were used in a fluid re‐circulation loop to simulate different types of blockage at various flow rates within the turbulent regime, generating patterns of acoustic emissions. The data were pre‐processed using Fourier analysis, and two candidate sets of statistical descriptors were extracted for each measurement. The first set used average and spread of the Fourier transform amplitudes, the second used data binning to obtain a concise representation of the spectrum of amplitudes. Experimental evidence showed the second set of descriptors was the most suitable to train the neural network to recognize with accuracy the presence and type of blockage. The obtained results compare favourably with the literature, indicating that the approach provides a tool to enhance process monitoring in water supply systems, in particular early detection of upstream blockages. [ABSTRACT FROM AUTHOR]

Technological developments require the transfer to their location of application to make use of them. We describe the transfer of a real‐time monitoring system for lab‐scale preparative chromatography to two new sites where it will be used and developed further. Equivalent equipment was used. The capture of a biopharmaceutical model protein, human fibroblast growth factor 2 (FGF‐2) was used to evaluate the system transfer. Predictive models for five quality attributes based on partial least squares regression were transferred. Six out of seven online sensors (UV/VIS, pH, conductivity, IR, RI, and MALS) showed comparable signals between the sites while one sensor (fluorescence) showed different signal profiles. A direct transfer of the models for real‐time monitoring was not possible, mainly due to differences in sensor signals. Adaptation of the models was necessary. Then, among five prediction models, the prediction errors of the test run at the new sites were on average twice as high as at the training site (model‐wise 0.9–5.7 times). Additionally, new prediction models for different products were trained at each new site. These allowed monitoring the critical quality attributes of two new biopharmaceutical products during their purification processes with mean relative deviations between 1% and 33%. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ultrasonic pretreatment is a novel physical method that can be used in the extraction process of okra pectin. Real‐time online monitoring technologies were introduced in time and frequency domains when okra was pretreated. Preparation time of dried okra and yield of okra pectin were studied; and physicochemical properties of okra pectin were analyzed at the optimum ultrasonic parameter. RESULTS: Results showed that ultrasonic intensity of sweeping‐frequency ultrasonic (SFU) pretreatment was stronger than that of fixed‐frequency ultrasonic pretreatment (FFU). SFU pretreatment (60 ± 1 kHz) at 30 min had a strong ultrasonic voltage peak of 0.05387 V and signal power peak of −6.62 dBm. The preparation time of dried okra was 160 ± 14.14 min in the pretreated group, 44.83% lower than control without SFU pretreatment. The intercellular space was 56.03% higher than control. Water diffusion coefficient increased from 1.41 × 10−9 to 2.14 × 10−9 m2 s−1. Monobasic quadratic equations were developed for the monitored ultrasonic intensity and pectin yield. Compared to control, extraction yield (16.70%), pectin content (0.564 mg mg−1), solubility (0.8187 g g−1) and gel strength (30.91 g) were improved in the pretreated group. Viscosity decreased, and values of G′ and G″ crossing at 63 rad s−1 revealed the viscoelastic behavior and the beginning of viscous behavior with a sol state. CONCLUSION: Decrement of dried preparation time and increment of yield were achieved by ultrasonic pretreatment during the extraction process of okra pectin, and the relationship of ultrasonic intensity monitored by real‐time online technologies and yield was given. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The transition from fossil to renewable energy sources requires adequate storage technologies due to the intermittency of the supplied energy. With respect to this, organic redox‐flow batteries (ORFBs) represent a promising concept for the storage of electricity on a large scale at economically justifiable costs. However, these storage technologies can only be operated reliably if parameters representing the actual condition of the storage medium (i.e., the electrolyte) can be accurately assessed. These so‐called electrolyte state variables are represented by two key figures of merit: state of charge (SOC), a measure of the amount of charge that the electrolyte currently holds; and state of health (SOH), representing the amount of charge that the electrolyte is able to store given its current condition. The herein presented IR‐based approach is able to simultaneously provide reliable, fast, accurate, and precise estimates for both SOC and SOH parameters at any point in time and independent of the current battery status. The method is able to provide a time resolution in the range of minutes, is independent of the electrolyte temperature and can be applied to nearly all organic‐based redox‐active materials and solvents, while potentially being applicable to inorganic RFBs, such as vanadium‐based systems, as well. [ABSTRACT FROM AUTHOR]

Polymerization processes with high reproducibility, traceability, and nontoxic compounds are required for biomedical applications. Here an automated solvent‐free polymerization of hyperbranched polyglycerol has been established on a multiple‐hundred gram scale. Performed is an anionic ring‐opening multibranching (ROMB) polymerization with slow addition of glycidol. The solvent‐free approach avoids commonly used organic solvents during the polymerization and work‐up. Due to the automation of the polymerization process a high reproducibility and traceability is accomplished. The used reactor is equipped with an anchor stirrer and stirrer control, which measures the applied torque. A linear correlation of the increasing torque and the degree of polymerization is observed, which can be used to monitor the molecular weight in situ during the polymerization. [ABSTRACT FROM AUTHOR]

In recent years, many fungal genomes have become publicly available. In combination with novel gene editing tools, this allows for accelerated strain construction, making filamentous fungi even more interesting for the production of valuable products. However, besides their extraordinary production and secretion capacities, fungi most often exhibit challenging morphologies, which need to be screened for the best operational window. Thereby, combining genetic diversity with various environmental parameters results in a large parameter space, creating a strong demand for time‐efficient phenotyping technologies. Microbioreactor systems, which have been well established for bacterial organisms, enable an increased cultivation throughput via parallelization and miniaturization, as well as enhanced process insight via non‐invasive online monitoring. Nevertheless, only few reports about microtiter plate cultivation for filamentous fungi in general and even less with online monitoring exist in literature. Moreover, screening under batch conditions in microscale, when a fed‐batch process is performed in large‐scale might even lead to the wrong identification of optimized parameters. Therefore, in this study a novel workflow for Aspergillus niger was developed, allowing for up to 48 parallel microbioreactor cultivations in batch as well as fed‐batch mode. This workflow was validated against lab‐scale bioreactor cultivations to proof scalability. With the optimized cultivation protocol, three different micro‐scale fed‐batch strategies were tested to identify the best protein production conditions for intracellular model product GFP. Subsequently, the best feeding strategy was again validated in a lab‐scale bioreactor. [ABSTRACT FROM AUTHOR]

Online monitoring of microbial cultures is an effective approach for studying both aerobic and anaerobic microorganisms. Especially in small‐scale cultivations, several parallel online monitored experiments can generate a detailed understanding of the cultivation, compared to a situation where a few data points are generated from time course sampling and offline analysis. However, the availability of small‐scale online monitoring devices for acetogenic organisms is limited. In this study, the previously reported anaerobic Respiration Activity MOnitoring System (anaRAMOS) device was adapted for online monitoring of Clostridium ljungdahlii (C. ljungdahlii) cultures with fructose as the carbon source. The anaRAMOS was applied to identify conversion of different carbon sources present in commonly used YTF medium. An iron(II) deficiency was discovered in this medium for C. ljungdahlii. Addition of iron(II) to the YTF medium reduced the cultivation time and increased biomass yield of C. ljungdahlii cultures by 50% and 40%, respectively. The measurement of the carbon dioxide transfer rate was used to calculated the iron(II) contained in complex components. By demonstrating the application of the anaRAMOS device for medium optimization, it is proven that the described online monitoring device has potential for use in process development. [ABSTRACT FROM AUTHOR]

The campaign life of the blast furnace is governed by the erosion of the hearth lining. Therefore, it is essential to keep track of the residual lining thickness not only for the better planning of the relining but also for the operational safety to avoid dangerous hearth breakthrough incidences. Modern blast furnaces are equipped with many thermocouples in the hearth refractory to monitor the temperature level. Higher temperatures indicate a lower residual wall thickness. However, the measured temperatures are also influenced by many other effects such as thermocouple defects, brittle layers in the refractory, hearth cooling system, production rate, temperature, and flow state of hot metal. Existing models lack comprehensive checks of the data plausibility or of possible effects unrelated to wear. The new multiphysics approach provides a flexible platform to include these influences as well as other physical aspects that are important for operational hearth monitoring. For instance, thermal stresses and the deformation of the hearth lining and steel shell can be analyzed. This enables the integration of strain‐gauge measurements into the model which were recently suggested for the monitoring of liquid levels. The numerical computations and visualization are performed using COMSOL Server with MATLAB for the 3D hearth geometry. This enables the use of a standard web browser to visualize the results interactively on any device connected to the internal network without any local software installation. The developed multiphysics model is calibrated and validated by comparing the estimated wear profile with the measured residual wall thickness during the blast furnace relinings in 2016 at Eisenhüttenstadt and Dillingen. Two instances of the multiphysics model are online and in use for monitoring the hearth lining state at these plants. [ABSTRACT FROM AUTHOR]

Juvenile idiopathic arthritis (JIA) is a chronic disease. During its "high disease activity (HDA)" stage, JIA can cause severe pain, and thus could seriously affect patients' physical and psychological health. Early detection of the HDA stage of JIA can reduce the damage of the disease by treating it at an early stage and alleviating the painful experience of the patients. So far, no effective cure of JIA has been found, and one major goal of disease management is to improve patients' quality of life. To this end, patients' health‐related quality of life (HRQOL) scores are routinely collected over time from JIA patients. In this paper, we demonstrate that a new statistical methodology called dynamic screening system (DySS) is effective for early detection of the HDA stage of JIA. By this approach, a patient's HRQOL scores are monitored sequentially, and a signal is given by DySS once the longitudinal pattern of the scores is found to be significantly different from the pattern of patients with low disease activity. Dimension reduction of the observed HRQOL scores and the corresponding impact on the performance of DySS are also discussed. [ABSTRACT FROM AUTHOR]

The growth of microorganisms on surfaces and interfaces as a biofilm is very common and plays important role in various areas such as material science, biomedicine, or waste treatment among others. Due to their inhomogeneous structure and the variance in the microorganism consortium, the analysis of biofilms represents a significant challenge. An online fluorescence sensor was developed that is able to measure the most important biological fluorophores (proteins, nicotinamide adenine dinucleotide, and flavin) in a noninvasive manner in biofilms, e.g. in bioelectrochemical applications. The sensor gives the opportunity to continuously draw conclusions on the metabolic state of the biofilm. The developed sensor has a diameter of 1 mm at the sensor tip and can be moved on and into the biofilm surface. In the first experiment, the measuring range of the sensor and the long‐term stability could be determined and the system applicability was confirmed. In addition, measurements in biofilm‐like structures could be performed. The formation of a wastewater‐based biofilm was monitored using the developed sensor, demonstrating the functionality of the sensor in a proof‐of‐principle experiment. [ABSTRACT FROM AUTHOR]

Liquid steel is typically stirred in a vacuum tank using argon gas injection to achieve a homogeneous composition and high‐purity steel. The aim of this work is to study the effect of vessel vibration on the operational state monitoring of the gas stirring in a vacuum tank degasser. Following an extensive analysis of vibration features, the root mean square (RMS) of vertical velocity is found to be the best feature for the measurement of the stirring intensity caused by the volumetric gas injection rate into the ladle. Smoothing is conducted using a centered median filter with a window length of 21 s. In this work, the operational state monitoring of gas stirring is described using a ladle responsiveness value (LRV). This describes the ability of a ladle to generate the maximum amount of vibration with the minimum amount of argon gas. The LRV summarized for each ladle reveals significant differences between them. Correspondingly, a rolling ladle responsiveness value (rLRV) is used for online monitoring of possible gas leakages. The rLRV can also be used for the online monitoring of the stirring efficiency and as its comparison with the overall efficiency of a specific ladle or all ladles. [ABSTRACT FROM AUTHOR]

Secretion of heterologous proteins into the culture supernatant in laboratory strains of Escherichia coli is possible by utilizing a Type I secretion system (T1SS). One prominent example for a T1SS is based on the hemolysin A toxin. With this system, heterologous protein secretion has already been achieved. However, no cultivations in a defined mineral medium and in stirred tank bioreactors have been described in literature up to now, hampering the broad applicability of the system. In this study, a mineral medium was developed for cultivation under defined conditions. With this medium, the full potential and advantage of a secretion system in E. coli (low secretion of host proteins, no contamination with proteins from complex media compounds) can now be exploited. Additionally, quantification of the protein amount in the supernatant was demonstrated by application of the Bradford assay. In this work, host cell behavior was described in small scale by online monitoring of the oxygen transfer rate. Scalability was demonstrated by stirred tank fermentation yielding 540 mg/L HlyA1 in the supernatant. This work enhances the applicability of a protein secretion system in E. coli and paves the way for an industrial application. [ABSTRACT FROM AUTHOR]

Bioprocesses operated in batch mode can induce adverse effects like overflow metabolism, substrate inhibition, osmotic inhibition, oxygen limitation, and catabolite repression. To avoid these adverse effects, fed‐batch is the predominant operation mode in industrial production. Nevertheless, screening for optimal production strains is usually performed in microtiter plates and shake flasks operated in batch mode without any online monitoring. Recently, a polymer‐based controlled‐release fed‐batch microtiter plate with stable glucose release characteristics was described. In this study, a glucose‐containing polymer matrix was used to manufacture polymer rings that were placed at the bottom of a 48‐well microtiter plate. Thereby, the liquid content of the well became accessible for optical measurement by the BioLector device. Reflections caused by the polymer ring were minimized by adjusting the scattered‐light measurement position. Influences on the measurement of the dissolved oxygen tension and pH could be avoided by choosing appropriate polymer‐ring geometries. These adjustments enabled parallel online measurement of scattered light, fluorescence, dissolved oxygen tension, and pH of Escherichia coli BL21 (DE3) fed‐batch cultivations. The online monitoring and fed‐batch operation capabilities of the fed‐batch microtiter plate presented in this study finds optimal application in screenings and initial process development. [ABSTRACT FROM AUTHOR]

In recent years, ultra‐wideband (UWB) systems have been proposed for online monitoring of power transformers. This study aims at a new UWB‐based method to determine the axial displacement (AD) extent in the transformer high‐voltage (HV) winding. In the proposed design, two receiving antennas and one transmitting antenna are used. Two receiving antennas receive signals at two different positions due to axial displacement occurrence, and the displacement extent is determined using an analytical method known as hyperbolic method, which is based on signals time difference of arrival. The proposed method is initially studied by simulations using computer simulation technology software. Finally, the experimental results show the effectiveness of the proposed method to detect the AD extent in an actual transformer winding. [ABSTRACT FROM AUTHOR]

The GIS is widely used in the power system. However, the overheating of the device contacts may cause serious accidents. A method of online monitoring of contact temperature of GIS equipment is put forward based on infrared sensing technology in view of the structural characteristics of GIS device. The method realises continuous and automatic measurement of temperature. The selection and installation location of temperature sensor are analysed, and here, the characteristics of GIS contact temperature measurement are studied. The GIS temperature measurement system is set up on the basis of previous research. The system is used to carry out experiments, whether the shielding cover of the device contact is existing in the process of temperature measurement is studied, respectively. The artificial neural network algorithm is used to process the data. The experimental results verify the feasibility and stability of the GIS contact temperature-monitoring system. The potential economic benefit of this study is huge and its application prospect is very broad. [ABSTRACT FROM AUTHOR]

Microfluidics can be used to handle relatively small volumes of samples and to conduct reactions in microliter-sized volumes. Electrospray ionization can couple microfluidics with mass spectrometry (MS) to monitor chemical reactions online. However, fabricating microfluidic chips is time-consuming. We herein propose the use of a micro-reactor that is sustained by two capillaries and an ultrasonicator. The inlets of the capillaries were individually immersed to two different sample vials that were subjected to the ultrasonicator. The tapered outlets of the two capillaries were placed cross with an angle of ~60° close to the inlet of the mass spectrometer to fuse the eluents. On the basis of capillary action and ultrasonication, the samples from the two capillaries can be continuously directed to the capillary outlets and fuse simultaneously to generate gas phase ions for MS analysis through ultrasonication-assisted spray ionization (UASI). Any electric contact applied on the capillaries is not required. Nevertheless, UASI spray derived from the eluents can readily occur in front of the mass spectrometer. That is, a micro-reactor was created from the fusing of the eluent containing different reactants from these two UASI capillaries, allowing reactions to be conducted in situ. The solvent in the fused droplets was evaporated quickly, and the product ions could be immediately observed by MS because of the extreme rise in the concentration of the reactants. For proof of concept, pyrazole synthesis reaction and cortisone derivatization by Girard T reagent were selected as the model reactions. The results demonstrated the feasibility of using UASI-based micro-reactor for online MS analysis to detect reaction intermediates and products. [ABSTRACT FROM AUTHOR]

SUMMARY: Background: Kt/Vurea reflects the efficacy of haemodialysis scaled to patient size (urea distribution volume). The guidelines recommend monthly Kt/V measurements based on blood samples. Modern haemodialysis machines are equipped with accessories monitoring the dose online at every session without extra costs, blood samples and computers. Objective: To describe the principles, devices, benefits and shortcomings of online monitoring of haemodialysis dose. Design: A critical literature overview and discussion. Results: UV absorbance methods measure Kt/V, ionic dialysance Kt (product of clearance and treatment time; cleared volume without scaling). Both are easy and useful methods, but comparison is difficult due to problems in scaling of the dialysis dose to the patient's size. Conclusions: The best dose estimation method is the one which predicts the quality of life and survival most accurately. There is some evidence on the predictive value of ionic dialysance Kt, but more documentation is required on the UV method. Online monitoring is a useful tool in everyday quality assurance, but blood samples are still required for more accurate kinetic modelling. Learning outcomes: After reading this article the reader should be able to: Understand the elements of the Kt/V equation for dialysis dose. Compare and contrast different methods of measurement of dialysis dose. Reflect on the importance of adequate dialysis dose for patient survival and life quality. [ABSTRACT FROM AUTHOR]

Abstract: Translating controlled/living radical polymerization (CLRP) from batch to the high throughput production of polymer libraries presents several challenges in terms of both polymer synthesis and characterization. Although recently there have been significant advances in the field of low volume, high throughput CLRP, techniques able to simultaneously monitor multiple polymerizations in an “online” manner have not yet been developed. Here, we report our discovery that 5,10,15,20‐tetraphenyl‐21H,23H‐porphine zinc (ZnTPP) is a self‐reporting photocatalyst that can mediate PET‐RAFT polymerization as well as report on monomer conversion via changes in its fluorescence properties. This enables the use of a microplate reader to conduct high throughput “online” monitoring of PET‐RAFT polymerizations performed directly in 384‐well, low volume microtiter plates. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Selected ion flow tube–mass spectrometry (SIFT‐MS) is a direct‐injection mass spectrometric technique that has been introduced recently into the field of food and flavor analysis. It also shows potential for use in the monitoring of food fermentations. Therefore, this study aimed at the online monitoring of different volatile compounds produced during starter culture‐initiated liquid sourdough fermentations by SIFT‐MS, for which a new workflow was developed. RESULTS: The online monitoring of the volatile sample compounds acetoin and ethyl acetate, diacetyl, and ethanol was made possible during the production of sourdoughs obtained through fermentation with several interesting strains belonging to the species Lactobacillus crustorum, Lactobacillus fermentum, Lactobacillus hilgardii, Lactobacillus nagelii, Lactobacillus sakei, and Gluconobacter oxydans. Acetoin and ethyl acetate could not be distinguished based solely on SIFT‐MS data. Diacetyl production was monitored in the case of Lb. crustorum LMG 23699 as a starter culture strain, thereby making the distinction between those volatiles produced in sourdough without extra ingredients added or after the addition of citrate or malate. CONCLUSION: Starter culture‐initiated liquid sourdough fermentations were monitored successfully. The volatile compound production of the different starter culture strains tested reflected differences in their metabolism and/or competitiveness in a sourdough matrix. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, the application of near-infrared (NIR) spectroscopy for online monitoring of the Moluodan extraction process was investigated. Paeoniflorin, the main active component of Moluodan, was chosen as the quality index. Samples were partitioned into calibration and validation sets by random select and set partitioning based on joint X-Y distances algorithm (SPXY), respectively. Wavelengths for modeling were selected by manual method and competitive adaptive reweighted sampling (Cars) algorithm. Particle swarm optimization-based least square support vector machines (PSO-LS-SVM) and partial least squares models were both established for quantitative analysis to determine the content of paeoniflorin online. At last, 8 models were obtained according to the combination of these algorithms and the SPXY-Cars-PSO-LS-SVM model had the best quantitative analysis performance compared with the other 7 models. Specifically, in the developed SPXY-Cars-PSO-LS-SVM model, the determination coefficients of the calibration R2c and validation R2v sets were 0.99 and 0.95, respectively, and the root mean square errors of the calibration and validation sets were 0.012 and 0.024 mg/mL, respectively, and the relative standard errors of the calibration and validation sets were 2.84% and 6.34%, respectively. These results suggested that the appropriate sample partition, wavelength selection, and regression analysis methods in this study, namely, the SPXY-Cars-PSO-LS-SVM algorithm combined with NIR spectroscopy, could be an effective and real-time approach for online monitoring of the extraction process of Moluodan. [ABSTRACT FROM AUTHOR]

To better assess the contribution of wind power plants (WPPs) during disturbances, Hydro‐Québec TransÉnergie (HQT), the main transmission system operator in the Quebec Interconnection, uses on‐line monitoring to record data at the point of common coupling of each WPP. This data is used to analyse their performance during voltage and frequency disturbances. Until recently, very few WPPs were able to provide an inertial response (IR) for under‐frequency events. On 28 December 2015, a generation loss of 1700 MW caused a frequency nadir of 59.08 Hz on the system, to which most WPPs required to provide IR contributed significantly. The analysis of the event showed that the behaviour of the WPPs had a significant effect on the recovery of the system frequency. This study presents the performance analysis of WPPs during this under‐frequency event. The analysis is based on data collected from 25 large‐scale WPPs in operation and equipped with the IR feature as required by HQT. Field measurements and simulation results are used to emphasise the effect of the active power reduction during the recovery phase. Impacts of the IR from the WPPs as used on the Hydro‐Quebec system are discussed. [ABSTRACT FROM AUTHOR]

Escherichia coli is commonly used for recombinant protein production with many available host strains. Screening experiments are often performed in batch mode using shake flasks and evaluating only the final product concentration. This conventional approach carries the risk of missing the best strain due to limited monitoring capabilities. Thus, this study focuses on investigating the general suitability of online respiration measurement for selecting expression hosts for heterologous protein production. The oxygen transfer rate (OTR) for different T7‐RNA polymerase‐dependent Escherichia coli expression strains was compared under inducing and noninducing conditions. As model enzymes, a lipase A from Bacillus subtilis (BSLA) and a 3‐hydroxybutyryl‐CoA dehydrogenase from Thermus thermophilus (HBD) were chosen. Four strains were compared during expression of both enzymes in autoinduction medium. Additionally, four strains were compared during expression of the BSLA with IPTG induction. It was found that the metabolic burden during recombinant protein production induces a phase of constant OTR, while undisturbed cell growth with no or little product formation is indicated by an exponential increase. This pattern is independent of the host strain, expressed enzyme, and induction method. Furthermore, the OTR gives information about carbon source consumption, biomass formation, and the transition from production to noninduced second growth phase, thereby ensuring a fair comparison of different strains. In conclusion, online monitoring of the respiration activity is suited to qualitatively identify, if a recombinant protein is produced by a strain or not. Furthermore, laborious offline sampling is avoided. Thus, the technique is easier and faster compared to conventional approaches. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:315–327, 2018 [ABSTRACT FROM AUTHOR]

The high-temperature trithiocarbonate-mediated reversible addition-fragmentation chain transfer (RAFT) polymerization of n-butyl acrylate is studied using a high-resolution mass spectrometric on-line monitoring method. Therefore, an Orbitrap mass spectrometer, ideally suited for polymer analysis, is coupled to a continuous flow microreactor. Via adjustment of flow rates in the reactor, time sweep experiments can be carried out to allow monitoring a whole polymerization in a single experiment. The n-butyl acrylate polymerization is monitored in a temperature interval between 100 and 190 °C for reaction times between 1 and 10 minutes. In all cases, full monomer conversions are reached and even at the highest temperatures still relatively good molecular weight control and reasonably low dispersities are obtained. End group analysis from mass spectrometry reveals, however, that the desired RAFT product is already at the lower temperatures less abundant than some side products. The herein described on-line monitoring technique gives access to quasi-continuous data acquisition, and is found to be very robust, and low in scattering when compared to classical batch sampling techniques. [ABSTRACT FROM AUTHOR]

The chemoselective, continuous, multistep reduction of iodo-nitroaromatics in a fixed-bed hydrogenation reactor has been investigated. This transformation poses challenges upon both the catalyst and process conditions if high yields are to be achieved. First, the stability and selectivity of four flow-compatible Pt catalysts, Pt(X)/C (X = Fe, V), were investigated by using 1-iodo-4-nitrobenzene as the model substrate. Granular Pt(Fe) on carbon was identified as the most promising candidate. With this catalyst, iodo-nitroaromatic API (active pharmaceutical ingredient) intermediate DIM-NA [(2,3-difluoro-5-methoxy-6-nitrophenyl)(2-fluoro-4-iodophenyl)amine] could be converted into the corresponding aniline with high selectivity on a preparative scale. UV/Vis spectroscopy was successfully applied for online conversion control, proving to be highly useful for detecting the effects of catalyst deactivation. [ABSTRACT FROM AUTHOR]

Measles virus (MV) has a natural affinity for cancer cells and oncolytic MV preparations have therefore been investigated in several clinical trials as a potential treatment for cancer. The main bottleneck in the administration of oncolytic MV to cancer patients is the production process, because very large doses of virus particles are required for each treatment. Here, we investigated the productivity of different host cells and found that a high infection efficiency did not necessarily result in high virus yields because virus release is also dependent on the host cell. As well as producing large numbers of active MV particles, host cells must perform well in dynamic cultivation systems. In screening experiments, the highest productivity was achieved by Vero and BJAB cells, but only the Vero cells maintained their high virus productivity when transferred to a stirred tank reactor. We used dielectric spectroscopy as an online monitoring system to control the infection and harvest times, which are known to be critical process parameters. The precise control of these parameters allowed us to achieve higher virus titers with Vero cells in a stirred tank reactor than in a static cultivation system based on T-flasks, with maximum titers of up to 1011 TCID50 ml−1. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:989-997, 2017 [ABSTRACT FROM AUTHOR]

A new approach to the analysis of the transient energy interaction in power systems is presented in this work on the basis of an analogous elastic network. A power system is first rigorously mapped to an elastic network consisting of elastic branches with different elasticity coefficients. On the basis of elasticity mechanics and the analogous elastic network, the transient energy of the different parts, such as the synchronous generators, branches, and loads, is defined and has been proved to agree with the law of energy conservation. Subsequently, based on the law of energy conservation and energy feature analysis, the concept of the power system energy structure (PSES) is built to exhibit the distribution and interaction of transient energy in the power system. Wide area and local area transient energy interaction can be analysed using the measurement‐based energy structure, which shows obvious potential in on‐line monitoring and analysis of power system oscillation. Finally, the simulations of Western Systems Coordinating Council (WSCC) three‐generator test system and a practical power system are performed and analysed to verify the rationality of the analogous elastic network and the validity of the proposed PSES. [ABSTRACT FROM AUTHOR]

This study presents the Hydro‐Québec TransÉnergie experience regarding the grid code compliance tests that have been performed for the integration of wind power plants using type‐III and type‐IV technologies. Tests discussed in this study were conducted in two phases: validation of the performance requirements for each project and type tests on a single wind turbine generator for each technology involved. The study presents examples of results for each test module and measurements from online monitoring. Technical challenges are discussed and performance issues that were raised through the process are explained. [ABSTRACT FROM AUTHOR]

Continuous flow synthesis techniques have in recent years conquered laboratory scale synthesis, yet within the field of precision polymer synthesis its use is still not fully established despite the large advantages that can be gained from switching from classical batch-wise chemistry to flow chemistry, often already by using relatively simple chip-based or cheap tubular micro- and mesoscaled reactors. Translating a polymerization from batch to continuous flow marks not only a mere change in reactor engineering, but also leads to numerous advantages in the polymerization with respect to kinetics of processes and especially product quality. In flow, polymerizations are not only speed up, they also provide materials with better dispersities and higher chain end fidelities when conditions are chosen accordingly. The underpinning effects causing these improvements are demonstrated and discussed. Further, also information on required laboratory equipment and recent developments in online reaction monitoring are highlighted to give newcomers to the field an idea about the potential of continuous flow polymerization. [ABSTRACT FROM AUTHOR]

ABSTRACT Microalgae offer great potential for the industrial production of numerous compounds, but most of the currently available processes fail on economic aspects. Due to the lack of appropriate microcultivation systems, especially screening and early stage laboratory process characterization limit throughput in process development. Consequently, a demand for high throughput photobioreactors has recently been identified upon which some prototype systems emerged. However, compared to microbial microbioreactors, the systems so far introduced suffer from at least one of several drawbacks, that is, inhomogeneous conditions, poor mixing or excessive evaporation. In this context, a microtiter plate based micro-photobioreactor was developed enabling 48-fold parallelized cultivation. Strict control of the process conditions enabled a high comparability between the distinct wells of one plate (±5% fluctuation in biomass formation). The small scale, resulting in a beneficial surface to volume ratio, as well as the fast mixing due to rigorous orbital shaking, ensured an excellent light supply of the cultures. Moreover, non-invasive online biomass quantification was implemented via a scattered light analyzer that is capable of biomass measurements during continuous illumination of the cultures. The system was shown to be especially qualified for parallelized laboratory screening applications like for instance media optimization. Easy automation via integration into a liquid handling platform is given by design. Thereby, the presented micro-photobioreactor system significantly contributes to improving the time efficiency during the development of phototrophic bioprocesses. Biotechnol. Bioeng. 2017;114: 122-131. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

On-line modeling of multivariate nonlinear system based on multivariate statistical methods has been studied extensively due to its industrial requirements. In order to further improve the modeling efficiency, a fast Block Adaptive Kernel Principal Component Analysis algorithm is proposed. Comparing with the existing work, the proposed algorithm (1) does not rely on iterative computation in the calculating process, (2) combines the up- and downdating operations to become a single one (3) and describes the adaptation of the Gram matrix as a series of rank-1 modification. In addition, (4) the updation of the eigenvalues and eigenvectors is of [ABSTRACT FROM AUTHOR]

The high-voltage distribution device is an important part of the power supply system which shoulders the dual tasks of control and protection. The function of the high-voltage distribution device is closely related to the safe operation of the power supply system. The condition monitoring of high-voltage distribution device can detect the specific parts of the fault in a timely and effective way which can improve the stability of the system. The mechanical vibration signal of circuit breaker body in mine high-voltage distribution device is a rich information carrier which contains a large number of device operating status information. Using modern information processing technology, the special parameters of mechanical faults are extracted from vibration signals, which have very important practical significance. Based on the analysis of the common mechanical faults in the high-voltage power distribution unit, a set of online vibration signal processing system with perfect function and reliable operation has been developed, which provides the technical guarantee for the reliable operation of the high-voltage power distribution unit. [ABSTRACT FROM AUTHOR]

Purpose: Accurate positioning of the target volume during treatment is paramount for stereotactic body radiation therapy (SBRT). In this work, the authors present the development of an in-house software tool to verify target position with an Elekta-Synergy linear accelerator using kV planar images acquired during treatment delivery. Methods: In-house software, SeedTracker, was developed in MATLAB to perform the following three functions: 1. predict intended seed positions in a planar view perpendicular to any gantry angle, simulating a portal imaging device, from the 3D seed co-ordinates derived from the treatment planning system; 2. autosegment seed positions in kV planar images; and 3. report the position shift based on the seed positions in the projection images. The performance of SeedTracker was verified using a CIRS humanoid phantom (CIRS, VA, USA) implanted with three Civco gold seed markers (Civco, IA, USA) in the prostate. The true positive rate of autosegmentation (TPRseg) and the accuracy of the software in alerting the user when the isocenter position was outside the tolerance (TPRtrig) were studied. Two-dimensional and 3D static position offsets introduced to the humanoid phantom and 3D dynamic offsets introduced to a gel phantom containing gold seeds were used for evaluation of the system. Results: SeedTracker showed a TPRseg of 100% in the humanoid phantom for projection images acquired at all angles except in the ranges of 80°-100° and 260°-280° where seeds are obscured by anatomy. This resulted in a TPRtrig of 88% over the entire treatment range for considered 3D static offsets introduced to the phantom. For 2D static offsets where the position offsets were only introduced in the anterior-posterior and lateral directions, the TPRtrig of SeedTracker was limited by both seed detectability and positional offset. SeedTracker showed a false positive trigger in the projection angle range between 130°-170° and 310°-350° (a maximum of 24% of treatment time) due to limited information that can be derived from monoscopic images. The system accurately determined the dynamic trajectory of the isocenter position in the superior and inferior direction for the studied dynamic offset scenarios based on the seed position in monoscopic images. Conclusions: The developed software has been shown to accurately autosegment the seed positions in kV planar images except for two 20° arcs where seeds are obscured by anatomical structures. The isocenter trajectories determined by the system, based on the monoscopic images, provide useful information for monitoring the prostate position. The developed system has potential application for monitoring prostate position during treatment delivery in linear accelerator based SBRT. [ABSTRACT FROM AUTHOR]

We examined how a friend's presence affects a performer's prefrontal activation in daily-life activities using two wireless portable near-infrared spectroscopy (NIRS) devices. Participants played a driving video game either solely in the single group or with a friend in the paired group. The two groups (single and paired) were subdivided according to their game proficiency (low and high). The NIRS data demonstrated a significant interaction of group by proficiency. Low-proficiency players in the paired group showed lower activation than those in the single group, but highproficiency players did not. In the paired group, high-proficiency players showed higher activation than low-proficiency players, but not in the single group. These results suggest that NIRS detects social presence effects in everyday situations: decreasing prefrontal activation in low-proficiency performers due to tension reduction and increasing prefrontal activation in high-proficiency performers due to increased arousal. [ABSTRACT FROM AUTHOR]

We present a fluorescence-lifetime based method for monitoring cell and tissue activity in situ, during cell culturing and in the presence of a strong autofluorescence background. The miniature fiber-optic probes are easily incorporated in the tight space of a cell culture chamber or in an endoscope. As a first application we monitored the cytosolic calcium levels in porcine tracheal explant cultures using the Calcium Green-5N (CG5N) indicator. Despite the simplicity of the optical setup we are able to detect changes of calcium concentration as small as 2.5 nM, with a monitoring time resolution of less than 1 s. (© 2013 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]