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Introduction: Terebinth (Pistacia terebinthus) belongs to the same botanical family as pistachio (Pistacia vera) and cashew (Anacardium occidentale). Although it is known that there is cross-sensitivity between pistachio and cashew, the cross-sensitivity of terebinth with pistachio or cashew has not been investigated. The objective of our study was to evaluate the sensitivity to terebinth in children with pistachio sensitivity. Methods: This study was conducted between September 2021 and June 2022 at Adıyaman University Faculty of Medicine Hospital. It analyzed the results of children who underwent skin prick testing (SPT) for food allergy. Of the 712 food skin prick tests reviewed, 27 children were identified with pistachio sensitivity. Prick tests with commercial extract for cashew and prick-to-prick tests for terebinth were applied to these children. Results: The median age was two, and 78% were male. Of the children with pistachio sensitivity, 96% demonstrated cross-sensitivity to terebinth and 100% to cashew. There was a strong correlation between the size of SPT responses in pistachio, cashew, and terebinth. Only four children had previously consumed terebinth, and two of these children had allergic reactions. Conclusion: Our study demonstrates a high cross-sensitivity between terebinth, pistachio, and cashew. We recommend that individuals with pistachio or cashew allergy/sensitivity avoid terebinth until tests confirm it is safe to consume. Further studies are needed to demonstrate the clinical significance of this cross-sensitivity and identify the major allergen involved. [ABSTRACT FROM AUTHOR]

Dissolved gas analysis (DGA) is considered to be the most convenient and effective approach for transformer fault diagnosis. Due to their excellent performance and development potential, chemiresistive gas sensors are anticipated to supersede the traditional gas chromatography analysis in the dissolved gas analysis of transformers. However, their high operating temperature and high power consumption restrict their deployment in battery-powered devices. This review examines the underlying principles of chemiresistive gas sensors. It comprehensively summarizes recent advances in low-power gas sensors for the detection of dissolved fault characteristic gases (H2, C2H2, CH4, C2H6, C2H4, CO, and CO2). Emphasis is placed on the synthesis methods of sensitive materials and their properties. The investigations have yielded substantial experimental data, indicating that adjusting the particle size and morphology structure of the sensitive materials and combining them with noble metal doping are the principal methods for enhancing the sensitivity performance and reducing the power consumption of chemiresistive gas sensors. Additionally, strategies to overcome the significant challenge of cross-sensitivity encountered in applications are provided. Finally, the future development direction of chemiresistive gas sensors for DGA is envisioned, offering guidance for developing and applying novel gas-sensitive sensors in transformer fault diagnosis. [ABSTRACT FROM AUTHOR]

Highlights: The types, working principles, advantages and limitations of pattern recognition methods based on chemiresistive gas sensor array are reviewed and discussed comprehensively. Outstanding and novel advancements in the application of machine learning methods for gas recognition in different important areas are compared, summarized and evaluated. The current challenges and future prospects of machine learning methods in artificial olfactory systems are discussed and justified. As information acquisition terminals for artificial olfaction, chemiresistive gas sensors are often troubled by their cross-sensitivity, and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing area. Pattern recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas sensors. It is crucial to choose an appropriate pattern recognition method for enhancing data analysis, reducing errors and improving system reliability, obtaining better classification or gas concentration prediction results. In this review, we analyze the sensing mechanism of cross-sensitivity for chemiresistive gas sensors. We further examine the types, working principles, characteristics, and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing arrays. Additionally, we report, summarize, and evaluate the outstanding and novel advancements in pattern recognition methods for gas identification. At the same time, this work showcases the recent advancements in utilizing these methods for gas identification, particularly within three crucial domains: ensuring food safety, monitoring the environment, and aiding in medical diagnosis. In conclusion, this study anticipates future research prospects by considering the existing landscape and challenges. It is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications. [ABSTRACT FROM AUTHOR]

Thermal conductivity sensors face an omnipresent cross-influence through varying humidity levels in real-life applications. We present the results of investigations on the influence of humidity on a hydrogen thermal conductivity sensor and approaches for predicting the behavior of thermal conductivity towards humidity. A literature search and comparison of different mixing equations for binary gas mixtures were carried out. The theoretical results were compared with experimental results from three different thermal conductivity sensors with mixtures of water vapor in nitrogen. The mixing equations show a large discrepancy between each other. Some of the models predict a continuously decreasing thermal conductivity and some predict an increasing thermal conductivity for increasing levels of humidity. Our measurements indicate an increase in thermal conductivity followed by a decrease after reaching a peak value. It is shown that the measured behavior is reproducible with different sensors. Depending on the sensor, this corresponds to an error up to 2 vol.% in the measured hydrogen value. The measured behavior is consistent with only one of the three models. Compared to this model, our own sensor shows a maximum deviation of 1.4%. Mixing equations for gas mixtures must be chosen carefully, taking into consideration whether mixing partners include polar or non-polar molecules. Some simplified mixing equations cannot be used to calculate the thermal conductivity of water vapor in air or nitrogen. [ABSTRACT FROM AUTHOR]

Highly sensitive and multimodal sensors have recently emerged for a wide range of applications, including epidermal electronics, robotics, health‐monitoring devices and human–machine interfaces. However, cross‐sensitivity prevents accurate measurements of the target input signals when a multiple of them are simultaneously present. Therefore, the selection of the multifunctional materials and the design of the sensor structures play a significant role in multimodal sensors with decoupled sensing mechanisms. Hence, this review article introduces varying methods to decouple different input signals for realizing truly multimodal sensors. Early efforts explore different outputs to distinguish the corresponding input signals applied to the sensor in sequence. Next, this study discusses the methods for the suppression of the interference, signal correction, and various decoupling strategies based on different outputs to simultaneously detect multiple inputs. The recent insights into the materials' properties, structure effects, and sensing mechanisms in recognition of different input signals are highlighted. The presence of the various decoupling methods also helps avoid the use of complicated signal processing steps and allows multimodal sensors with high accuracy for applications in bioelectronics, robotics, and human–machine interfaces. Finally, current challenges and potential opportunities are discussed in order to motivate future technological breakthroughs. [ABSTRACT FROM AUTHOR]

The degradation of sulfacetamide with the formation of sulfanilamide leads to a deterioration in the quality of pharmaceuticals. In this work, potentiometric sensors for the simultaneous determination of sulfanilamide, sulfacetamide and inorganic ions, and for assessing the degradation of pharmaceuticals were developed. A multisensory approach was used for this purpose. The sensor cross-sensitivity to related analytes was achieved using perfluorosulfonic acid membranes with poly(3,4-ethylenedioxythiophene) or polyaniline as dopants. The composite membranes were prepared by oxidative polymerization and characterized using FTIR and UV-Vis spectroscopy, and SEM. The influence of the preparation procedure and the dopant concentration on the membrane hydrophilicity, ion-exchange capacity, water uptake, and transport properties was investigated. The characteristics of the potentiometric sensors in aqueous solutions containing sulfanilamide, sulfacetamide and alkali metals ions in a wide pH range were established. The introduction of proton-acceptor groups and π-conjugated moieties into the perfluorosulfonic acid membranes increased the sensor sensitivity to organic analytes. The relative errors of sulfacetamide and sulfanilamide determination in the UV-degraded eye drops were 1.2 to 1.4 and 1.7 to 4%, respectively, at relative standard deviation of 6 to 9%. [ABSTRACT FROM AUTHOR]

Accurate and real-time detection of characteristics gases is crucial for Dissolved Gas Analysis (DGA) in electrical transformers. Conventional assessments of Metal-Oxide Semiconductor (MOS) sensor selectivity generally analyze the response to singular interfering gases at identical concentrations, failing to represent the realistic intricacies of multi-component gases environments in DGA. Cross-sensitivity complicates the assessment of selectivity. This study proposes a method for re-assessing the selectivity of MOS sensor by considering cross-sensitivity in multi-component gases. Utilizing the Kendall correlation coefficient to analyze the relationship between characteristic gas concentrations and dynamic sensor responses, we determined sensor selectivity, optimal operating temperatures, and sensor interchangeability. Furthermore, we use a new term of quasi-2D sensor characteristics, which facilitated the creation of a complementary sensor array that significantly enhances gas selectivity and effectively mitigates MOS sensor saturation challenges. The complementary array, assessed by Linear Discriminant Analysis (LDA) projections and kernel density estimation, demonstrated enhanced selectivity relative to previous sensor arrays in the detection of multi-component gases. This method not only improves sensor selectivity but also mitigates cross-sensitivity in multi-component gas environments. Future research could focus on assessing a substantial array of MOS sensors, considering particular cross-sensitivity backgrounds, to improve artificial intelligence algorithms for accurate and real-time DGA detection. [Display omitted] • Correlation coefficient quantified sensor selectivity in mixed gas. • Assessment results addressed the impact of operating temperature in mixed gas. • Assessment process quantified sensor interchangeability in mixed gases. • Resistance alteration exhibited directionality between highly selective and mixed gases. [ABSTRACT FROM AUTHOR]

For decades, Metal oxide (MOX) gas sensors have been commercially available and used in various applications such as the Smart City, gas monitoring, and safety due to advantages such as high sensitivity, a high detection range, fast reaction time, and cost-effectiveness. However, several factors affect the sensing ability of MOX gas sensors. This article presents the results of a study on the cross-sensitivity of MOX gas sensors toward ambient temperature and humidity. A gas sensor array consisting of temperature and humidity sensors and four different MOX gas sensors (MiCS-5524, GM-402B, GM-502B, and MiCS-6814) was developed. The sensors were subjected to various relative gas concentrations, temperatures (from 16 °C to 30 °C), and humidity levels (from 75% to 45%), representing a typical indoor environment. The results proved that the gas sensor responses were significantly affected by the temperature and humidity. The increased temperature and humidity levels led to a decreased response for all sensors, except for MiCS-6814, which showed the opposite response. Hence, this work proposed regression models for each sensor, which can correct the gas sensor response drift caused by the ambient temperature and humidity variations. The models were validated, and the standard deviations of the corrected sensor response were found to be 1.66 kΩ, 13.17 kΩ, 29.67 kΩ, and 0.12 kΩ, respectively. These values are much smaller compared to the raw sensor response (i.e., 18.22, 24.33 kΩ, 95.18 kΩ, and 2.99 kΩ), indicating that the model provided a more stable output and minimised the drift. Overall, the results also proved that the models can be used for MOX gas sensors employed in the training process, as well as for other sets of gas sensors. [ABSTRACT FROM AUTHOR]

Purpose: Amperometric gas sensors are commonly used in air quality monitoring in long-term measurements. Baseline shift of sensor responses and power failure may occur over time, which is an obstacle for reliable operation of the entire system. The purpose of this study is to check the possibility of using PCA method to detect defected samples, identify faulty sensor and correct the responses of the sensor identified as faulty. Design/methodology/approach: In this work, the authors present the results obtained with six amperometric sensors. An array of sensors was exposed to sulfur dioxide at the following concentrations: 0 ppm (synthetic air), 50 ppb, 100 ppb, 250 ppb, 500 ppb and 1000 ppb. The damage simulation consisted in adding to the sensor response a value of 0.05 and 0.1 µA and replacing the responses of one of sensors with a constant value of 0 and 0.15 µA. Sensor validity index was used to identify a damaged sensor in the matrix, and its responses were corrected via iteration method. Findings: The results show that the methods used in this work can be potentially applied to detect faulty sensor responses. In the case of simulation of damage by baseline shift, it was possible to achieve 100% accuracy in damage detection and identification of the damaged sensor. The method was not very successful in simulating faults by replacing the sensor response with a value of 0 µA, due to the fact that the sensors mostly gave responses close to 0 µA, as long as they did not detect SO2 concentrations below 250 ppb and the failure was treated as a correct response. Originality/value: This work was inspired by methods of simulating the most common failures that occurs in amperometric gas sensors. For this purpose, simulations of the baseline shift and faults related to a power failure or a decrease in sensitivity were performed. [ABSTRACT FROM AUTHOR]

The admittance-type-level sensor is used for continuous level measurement in both metallic and nonmetallic tanks. However, the use of this sensor is limited because of the significant nonlinearity and cross-sensitivity. In this work, the authors have proposed the concept of a double-electrode admittance-type-level sensor. The said level sensor measures the level and the temperature of a conductive liquid. The multifunctional measurement is possible by the detection of the extent of cross-sensitivity using fuzzy logic and decomposition of the measurement variables. The experimental prototype of the sensor and associated instrumentation have been developed, and from the experimental results, it is found that the error in the measurement is consistently distributed and within the range of 1.86% for the level and 2.73% for temperature, which demonstrates the appropriateness of the design. This measurement system and sensor design can be implemented in the boiler-drum-level measurement for better drum-level control. [ABSTRACT FROM AUTHOR]

A novel technology for the simultaneous and independent measurement of dual parameters is proposed and experimented. By using a single fiber Bragg grating half-pasted by 1C-LV epoxy under different curing conditions, the sensor structure is designed such that the reflective single-peak spectrum splits into a twin-peak spectrum, which makes the FBG spectrum form a natural spectral peak splitting bias. A measurement limitation exists in the FBG sensor packaging at room temperature, which can be solved by the high-temperature cured packaging method. To verify the validity of the theory and methodology, the experimental system is used. In the range from -1000 to +1000 με and from 35 to 75°C, the Bragg wavelength change is relative linear to the strain and temperature. The temperature and strain variations can be independently and simultaneously measured using the split peak, and the deviations of the FBG sensor are ±1°C and ±5 με, respectively. This single FBG sensor can realize dual-parameter measurement, which is valuable for narrow-space health monitoring. [ABSTRACT FROM AUTHOR]

A key element in the safe operation of a modern gas distribution system is gas detection. The addition of hydrogen to natural gas will alter the characteristics of the fuel and, therefore, its impact on gas detection must be considered. It is important that gas detectors remain sufficiently sensitive to the presence of hydrogen and natural gas mixtures, and that they do not lead to false readings. This paper presents analyses of work performed as part of the Office for Gas and Energy Markets (OFGEM) funded HyDeploy project, on the response of various natural gas industry detectors to blended mixtures up to 20 vol percent (vol%) of hydrogen in natural gas. The scope of the detectors under test included survey instruments and personal monitors that are used in the gas industry. Four blend ratios were analysed (0, 10, 15 and 20 vol% hydrogen in natural gas). The laboratory testing undertaken investigated the following: • Flammable response to blends in the ppm range (0–0.2 vol%); • Flammable response to blends in the lower explosion limit range (0.2–5 vol%); • Flammable response to blends in the volume percent range (5–100 vol%); • Oxygen response to blends in the volume percent range (0–25 vol%); and. • Carbon monoxide response to blends in the ppm range (0–1000 ppm). Catalytic and thermal conductivity based flammable detectors in the volume percent range are, as expected, affected in the form of a relative increase in output. All of the carbon monoxide detectors tested were found to be cross-sensitive to hydrogen in the blended mixtures tested at levels which have the potential to cause false alarms at current permissible leakage rates. In summary, a number of measurement ranges across multiple detectors commonly used in the gas industry have been found to be cross-sensitive to hydrogen in natural gas blends to differing degrees. This required the HyDeploy project to select alternative instruments for the purpose of gas detection as part of the trial. This paper relates to the preparatory work to introduce hydrogen into the Keele closed network. • Current gas detector designs are not suitable for a H2/NG blended trial. • A maximum CO cross-sensitivity to H 2 of ≤1.5% is required for a trial detector. • There are no known hydrogen compensated domestic CO detectors on the market. • An IR instrument has been chosen with an LEL calibrated for worst-case blends. • The solutions proposed for Keele are designed to be safe and are conservative. [ABSTRACT FROM AUTHOR]

In recent years, smog and poor air quality have become a growing environmental problem. There is a need to continuously monitor the quality of the air. The lack of selectivity is one of the most important problems limiting the use of gas sensors for this purpose. In this study, the selectivity of six amperometric gas sensors is investigated. First, the sensors were calibrated in order to find a correlation between the concentration level and sensor output. Afterwards, the responses of each sensor to single or multicomponent gas mixtures with concentrations from 50 ppb to 1 ppm were measured. The sensors were studied under controlled conditions, a constant gas flow rate of 100 mL/min and 50 % relative humidity. Single Gas Sensor Response Interpretation, Multiple Linear Regression, and Artificial Neural Network algorithms were used to predict the concentrations of SO2 and NO2. The main goal was to study different interactions between sensors and gases in multicomponent gas mixtures and show that it is insufficient to calibrate sensors in only a single gas. [ABSTRACT FROM AUTHOR]

We propose a general methodology to calculate the individual sensitivity and the cross-sensitivities of potentiometric sensor devices (e.g., ion sensitive FETs (ISFETs), CHEMFETs) with an arbitrary number of non-interacting receptors binding to ionic species or analytes in the electrolyte. The surface charge generated at the (bare or functionalized) interface with the electrolyte is described by the Poisson equation coupled to a linear system of equations for each type of receptor, where the unknowns are the fractions of sites binding with a given ion/analyte. Our general model encompasses in a unique framework a few simple special cases so far separately reported in the literature and provides for them closed-form expressions of the average site occupation probability. Detailed procedural description of the usage and benefits of the model is shown for specific cases with concurring surface chemical reactions. [ABSTRACT FROM AUTHOR]

Cross-sensitivity among chemical gas sensors leads to inaccurate identification of mixed gas. Pattern recognition algorithms are usually applied to improve the recognition accuracy. However, the abilities of current methods to process sequence property of response data are not strong enough. Especially, they cannot deal with bidirectional cross-sensitive issue, leading to recognition errors. Bidirectional Recurrent Neural Network (BRNN) could well learn bidirectional association features between word sequences in natural language processing field, which is similar to the bidirectional interaction of cross-sensitivity. In this study, an improved deep BRNN model was constructed to solve the cross-sensitivity problem of chemical gas sensor array. A chemical gas sensor array with four units was fabricated and response data was thoroughly obtained. Data preprocessing methods, model structure hyperparameters and optimizers were studied. Finally, an improved deep BRNN model was developed with 3 layers and 100 hidden_size, training with Adamax optimizer. A recognition accuracy of 98.93% was achieved, attributing to the model's excellent learning ability to the bidirectional cross-sensitivity rules among gas sensors. This improved BRNN model provided a novel idea to eliminate cross-sensitivity, exhibiting good potential for recognizing mixed gas analyte accurately. • A 3-layer deep BRNN with 100 hidden_size eliminated cross-sensitivity of gas sensor array. • Embedding layer and decimal places of data reduced helped to provide effective input in time. • Bidirectional self-learning ability to process sequence data helped to achieve good recognition accuracy. [ABSTRACT FROM AUTHOR]

Highlights • A novel Photonic Crystal Fiber (PCF) structure with dual Surface Plasmon Resonance (SPR) was proposed. • Temperature and strain can be simultaneously measured. • The sensor has high sensitivity, simple and robust structure. Abstract A novel Photonic Crystal Fiber (PCF) structure with dual Surface Plasmon Resonance (SPR) was proposed to implement simultaneous measurement of temperature and strain and resolve the cross-sensitivity problem between temperature and strain. Two symmetrical holes of the PCF was coated with golden layer and one of which was infiltrated with temperature-sensitive liquid. Through theory and numerical analyses, the influences of temperature and strain on structural parameters of the PCF were discussed and calculated. Simulation results demonstrated that the temperature and strain could be simultaneously measured with sensitivities of −6.83 nm/°C and 1.30 × 10−3 nm/με, respectively, when diethylene glycol was chosen as the temperature sensitive liquid. In particular, the influence of strain variation on the temperature sensing characters was analyzed and compensated, which could further guarantee the measurement precision of temperature. [ABSTRACT FROM AUTHOR]

Highlights • A multifunctional sensor based on GFET is studied with a decoupling technique. • A decoupling technique is designed to precisely identify various environment signals. • The decoupling technique can identify two environment values from outputs of the single GFET. Abstract Graphene is one of good candidates for application to multifunctional sensors due to its unique material properties, extremely high surface-to-volume ratio and ability to be effectively co-integrated on various substrates. However, the electrical properties of graphene are sensitive to most typical environment signals such as temperature, light, humidity, and gas. Therefore, to develop graphene-based multifunctional sensors, it is essential to identify multiple environment information values from the output characteristics of a single graphene sensor. In this study, we developed a temperature–illuminance multifunctional graphene sensor that can identify both temperature and illuminance values. We also propose a decoupling technique to enable the precise identification of temperature and illuminance values from the output characteristics of a sensor that has cross-sensitivity to the both inputs. This decoupling technique is developed based on the different gate-voltage dependence of the temperature- and illumination-induced modulations of the graphene conductivity. The results show that graphene can be used as a material for multifunctional sensors when combined with an appropriate decoupling technique for identifying various types of environment signals. [ABSTRACT FROM AUTHOR]

Due to the nitrogen oxide (NOx) sensor's cross-sensitivity and inability to monitor ammonia coverage, it is critical to eliminate these flaws for a significant percentage of in-use diesel vehicles without NH 3 sensors. In this study, a platform for multi-model co-simulation was established. The results showed that the downstream NOx concentration of the selective catalytic reduction (SCR) could be more accurately calculated using the filtering model based on cubature Kalman filter (CKF). Under European Steady-State Cycle (ESC) and European Transient Cycle (ETC), the prediction errors of the filtering model based on CKF were 4.6% and 7.7%, respectively. Under ESC, compared with the old control strategy, the prediction accuracy of temperature model of the new control strategy was increased by 2.6%, the average Adblue injection rate was increased by 9.1%, and the average NOx conversion efficiency was increased by 4.3%. Under ETC, the prediction accuracy of the temperature model of the new control strategy was increased by 2.5%, leading to a high average NOx conversion efficiency of 87.9%. Regarding the old control strategy, although the average NOx conversion efficiency reached 92.1%, the average ammonia slip concentration exceeded the threshold (10 ppm) by more than five times. • The objective is to optimize the cross sensitivity of NOx sensor and reduce NOx emission. • The prediction errors of filtering model are within 4.6% and 7.7% respectively under ESC and ETC. • The average NOx conversion efficiency of the new control strategy increased by 4.3% under ESC. • The Adblue injection is increased by 9.1% under ESC and reduced by 13.2% under ETC. [ABSTRACT FROM AUTHOR]

Unsatisfactory sensing performance in terms of lack of selectivity and cross-sensitivity to humid environment remains a challenging issue for Ti 3 C 2 T x MXene-based sensors. In this direction, the present study investigates the WS 2 /MXene composite-based chemiresistive sensor, utilizing the synergistic benefits of active adsorption sites of WS 2 nanosheets with large surface and high conductive platform of multi-layered MXene sheets. The different weight proportions of WS 2 to MXene were synthesized and a sensor fabricated using 25 wt % WS 2 /MXene exhibited preeminent response of 3–29 % and 6.87–44 % within range of 0.1–5 ppm NH 3 and 1–100 ppb NO 2 , respectively. More importantly, the opposite transient response curves were observed for NH 3 (increase in resistance) and NO 2 (decrease in resistance), which served as a basis for their discrimination. Further, density functional theory simulations were performed to better comprehend the gas detecting capabilities of material, showing the high adsorption energies of WS 2 /MXene surface towards NH 3 and NO 2. Moreover, the humidity cross-sensitivity studies with NH 3 and NO 2 were also taken, and the sensor showed high resilience to humidity. Finally, an LED sensing module was employed to further distinguish the detection of NH 3 and NO 2 , which showed the possibility of practical application of dual sensing using single sensing material. [Display omitted] • WS 2 nanosheets decorated multi-layered MXene based chemiresistive sensor is fabricated for NH 3 and NO 2 detection. • The sensor exhibits response of 3–29 % and 6.87–44 % towards 0.1–5 ppm NH 3 and 1–100 ppb NO 2 , respectively. • The opposite transient response curves are observed for NH 3 (increase in resistance) and NO 2 (decrease in resistance). • An LED sensing module was employed to further distinguish the detection of NH 3 and NO 2. [ABSTRACT FROM AUTHOR]

Highlights • A compact reflective fiber laser refractometer is demonstrated. • The sensing system is power modulation. • The structure is suitable for precise localized measurement. • The temperature cross-sensitivity can be effectively compensated. Abstract A temperature-compensated fiber laser refractometer based on compact hybrid S fiber taper (SFT)/fiber Bragg grating (FBG) structure is proposed. The SFT is used as a sensing component as well as a band-pass filter (BPF) to tailor the FBG reflection, which has the micro size of 0.78 mm. Owing to the RI-dependence intra-cavity loss, the output power of the erbium-doped fiber ring laser (FRL) can be modulated by the surrounding refractive index (SRI). During the measurement range of 1.3330–1.4060, the refractometer provides a high sensitivity of 269.76 dB/RIU. By using the sensing matrix containing the SRI as well as temperature sensitivities for the output power and lasing wavelength, the temperature cross-sensitivity problem can be effectively resolved. [ABSTRACT FROM AUTHOR]

Nowadays there exists a large variety of Ion Selective Electrodes with chalcogenide glasses as sensitive membrane. This short review paper will discuss the development of these sensors for the last almost fifty years. The glass compositions, response modelling, construction methods, parameters evaluation and applications are reviewed. Research breakthroughs and remaining problems on chalcogenide glass Ion Selective Electrodes are discussed. [ABSTRACT FROM AUTHOR]

Hybrid materials based on perfluorosulfonic cation-exchange membranes and silica nanoparticles with surface modified by nitrogen-containing groups have been obtained. The influence of concentration, size and proton acceptor ability of modifying groups on the oxide surface onto the response stability and sensitivity of potentiomentric sensors in aspartic and glutamic acid solutions with pH 4–9 has been investigated. A correlation between sensor cross-sensitivity to cations and anions in test solutions and membrane diffusion permeability is revealed. Optimal membrane compositions for arrays of cross-sensitive sensors have been chosen. Proposed sensors allow to carry out a simultaneous determination of potassium cations and amino acid anions in test solutions with concentrations ranged from 1.0·10 −4 to 1.0·10 −2  M, with an error < 14%. [ABSTRACT FROM AUTHOR]

Background: Cross‐sensitivity of rash has been reported between various antiepileptic drugs (AEDs). However, few studies have determined the frequency and management of cross‐sensitivity in patients with super‐refractory status epilepticus (SRSE). Aims of the study: To examine the optimal AED for treating SRSE with cross‐sensitivity. Methods: We performed a retrospective review of adult patients with SRSE treated at Nagoya City University Hospital, in which we investigated the frequency of cross‐sensitivity among patients with SRSE and their clinical and medical profiles. Results: We identified 10 adult patients with SRSE, 5 of whom had cross‐sensitivity. Stiripentol (STP) was administered when previously used AEDs had demonstrated cross‐sensitivity and failed to control seizures. After initiation of STP, the dose of general anaesthetics was reduced, and status epilepticus (SE) eventually ceased with co‐administered AEDs without additional adverse effects. The mean time to SE cessation after initiation of STP was 30.8 days (range, 18‐46 days), mean duration of general anaesthesia was 101.2 days (range, 74‐128 days), and mean number of AEDs was 9.0 (range, 6‐11). Conclusions: This study suggests that cross‐sensitivity between AEDs is common in adults with SRSE and that STP may be useful for treating SRSE with cross‐sensitivity. [ABSTRACT FROM AUTHOR]

• A physics-based sensitivity model of 3-Axis-Gs is established. • Triaxial synchronous loading can cover the entire calibration range. • A new experimental method to realize triaxial synchronous calibration is proposed. • Cross-axis sensitives of a 3-Axis-G is tested by the triaxial synchronous method. • Installation orientation error of sensitive axes can be preliminarily predicted. Because the inter-axis coupling effect and nonlinearity of triaxial high-g accelerometers (3-Axis-Gs) are significant under high-g and high-frequency loads, calibrating the sensitivity characteristics using a triaxial synchronous method is necessary but experimentally difficult. This study focused on the physics-based sensitivity model of 3-Axis-Gs, as well as the principle and experimental method of triaxial synchronous calibration. First, a sensitivity model of 3-Axis-Gs was established based on the physical source of cross-sensitivity. Then, a new triaxial synchronous calibration method was proposed using the modified Hopkinson pressure bar, which can simultaneously apply excitation accelerations with amplitudes greater than 100,000 g and frequencies greater than 50 kHz along the three axes of 3-Axis-Gs. Finally, a 3-Axis-G was calibrated using both triaxial synchronous and uniaxial calibration methods. Compared with uniaxial calibration, triaxial synchronous calibration can cover the entire test range, whose results can reflect the actual cross-sensitivity characteristics of 3-Axis-Gs in a three-dimensional loading environment. [ABSTRACT FROM AUTHOR]

Gas sensors play an essential bridge in connecting humans and health by helping people monitor the gas quality in their living spaces. In this work, PtNi 3 -WO 3 gas sensors were fabricated and demonstrated superior selectivity, sensitivity, and stability to formic acid, which was sufficient for indoor air gas monitoring. The response to 100 ppm formic acid was as high as 591, with a response time of only 3 s, and detection range down to the ppb level. The bimetal PtNi 3 decorated sensors showed a 30 times improvement in formic acid response compared to pure WO 3 sensors. The cross-sensitivity was investigated, and we observed that the response initially decreased and then increased in a mixed gas with a constant concentration of carboxylic acid and increasing gradually concentration of formaldehyde. The adsorption and desorption mechanisms were studied, which implied that the decomposition and adsorption behavior of the gas could change and produce different intermediate products under different mixing environments. The results of the energy surface testing and density functional theory supported the proposed sensing mechanism. A machine-learning framework was developed for gas identification and concentration prediction, which achieved ultra-high identification accuracy. In addition, Bluetooth-based portable gas sensors were demonstrated, showing promising practical applications. [Display omitted] • The bimetal decorated PtNi x -WO 3 sensors presented superior sensitivity, selectivity, and stability in detecting formic acid. • The mixed gas adsorption was strongly related to the dispersive and polar sites on the sensing material surfaces. • The machine learning model had 100% accuracy in identifying formic acid and 90.8% accuracy in predicting its concentration. • The Bluetooth-based portable gas sensor demonstrated stable performance for 2 months without significant variation. [ABSTRACT FROM AUTHOR]

Background: Penicillin (PNC) allergy is a major healthcare concern that necessitates antibiotic substitution which is associated with increased costs, worse clinical outcomes, and increased risks of antimicrobial resistance. Many patients are labeled as PNC allergic; however, this has been rarely confirmed. In this audit, we aimed to determine the characteristics of PNC allergy labeling. Methods: A list of all the patients labeled with PNC allergy who presented to the Hamad General Hospital (HGH) for any medical reason from January to December 2021 was generated from pharmacy system. Of those, 30% were randomly selected for audit review. Electronic health records of the selected patients were retrospectively reviewed to identify the allergy labeling characteristics and whether the patients had recently received an antibiotic within the PNC class without developing any allergic reaction. Results: Of the 464 patients identified with labelled PNC allergy, 139 patients were randomly selected and reviewed. Of the reviewed patients, 82 (59%) were women with an average (± SD) age of 46 (± 16.5) years. Forty-six patients were categorized to have a mild PNC allergy, and only 18 were categorized as severe with the remaining patients categorized as having a moderate PNC allergy. Despite documentation of severity, an accurate description of the allergic reaction event was significantly lacking with only 30/139 (21.5%) patients having clear documentation of the event description. Twenty (14.4%) patients labeled as PNC allergic received at least one antibiotic within the PNC class (e.g., piperacillin-tazobactam, ampicillin-sulbactam, or amoxicillin-clavulanic acid) safely without any documented reactions. Interestingly, of those 20 patients, 4 were categorized as being severely allergic to PNC. However, as more than 80 patients presented to the hospital for reasons not requiring antibiotics; experiences with PNC could not be assessed effectively. Conclusion: Poor documentation of the details of allergic reactions may falsely affect future antibiotic decisions. The results of this audit highlight the need for standardizing the documentation process of medication allergy. In addition, reviewing the patient's experience with other drugs within the PNC class can guide healthcare providers during the PNC allergy evaluation. [ABSTRACT FROM AUTHOR]

Three sweet corn genotypes, two inbred lines (IBER001 and IBER002) and their hybrid (ER00X), differ in their phenotypic responses to several P450-metabolized herbicides, used in sweet corn, namely, foramsulfuron, iodosulfuron, rimsulfuron and tembotrione. Foramsulfuron is a sulfonylurea herbicide commonly formulated with the safener isoxadifen that is used for selective post-emergence weed control in corn. Our goal was to elucidate the mechanism of these genotypes' responses to foramsulfuron and safener isoxadifen and examine the heritability of those responses. IBER001 was sensitive to foramsulfuron + isoxadifen, with an ED 50 of 3.6 g ai ha − 1 , while IBER002 and ER00X were tolerant with ED 50 values of 808 and 700 g ai ha − 1 , respectively. ALS enzyme extracted from each of the different genotypes was equally sensitive to foramsulfuron. Pre-treatment with malathion, a known cytochrome P450 inhibitor, increased foramsulfuron injury in IBER002 and ER00X, but had no effect on those lines when isoxadifen was applied with the herbicide. Foramsulfuron-treated IBER001 was severely injured regardless of the presence of malathion and/or isoxadifen. Pre-treatment with malathion similarly increased the phytotoxicity of iodosulfuron + safener (mefenpyr) and rimsulfuron to the tolerant genotypes, but did not increase the level of injury caused by the tembotrione + isoxadifen treatment. Segregation of F2 and backcross progenies according to their responses to foramsulfuron + isoxadifen revealed a pattern of inheritance typical of a trait controlled by a single gene inheritance, with a recessive allele conferring sensitivity. Our results support the hypothesis that foramsulfuron selectivity is associated with P450 metabolism and that isoxadifen positively affects P450 activity. The sensitive genotype that does not respond to isoxadifen is presumably homozygous for a deficient or non-functioning P450 gene. [ABSTRACT FROM AUTHOR]

3D Hall sensors generally suffer from cross-sensitivity among measurement axes, which limits their accuracy compared to 1D Hall sensors, and complicates their calibration. To overcome these issues, a time-effective and intuitive calibration and field reconstruction method is proposed which is well-suited, but not limited, to a new type of 3D Hall sensor (“Hallcube”) consisting of six orthogonally arranged 1D Hall sensors that form a sub-millimeter active volume, and pairwise compensate for the planar Hall effect. Generally, the method is applicable to 3D Hall sensors that are composed of separate 1D Hall sensors, and show negligible planar Hall voltage (inherently or after compensation). The method is based on a two-step calibration scheme: (1) determination of the relative placement of the six constituent Hall sensors, and (2) calibration of each of the six sensors analogously to a standard 1D Hall sensor calibration. From the normal vectors and the voltage-to-magnetic-field characteristic of each sensor, the full magnetic field vector can be reconstructed. The proposed method was applied to the first prototype Hallcube sensor which achieved an accuracy of 800 ppm at the 1 T level for any direction of the field vector. The accuracy-limiting factor was the underperformance of the 1D Hall sensors, whose Hall voltages display a long-term instability of >600 ppm. [ABSTRACT FROM AUTHOR]

Sensor systems designed to determine external measurands often show parasitic sensitivities to other influences, so-called disturbances. Calibration of such a system aims for the extraction of disturbance-compensated measurand values from the system output signals. Often this goal is achieved by exposing the system to a sufficient number of load conditions involving well-controlled values not only of the measurands but also of the disturbances. In this work we show that the calibration effort focused exclusively on the extraction of disturbance-compensated measurand values can be considerably reduced in the case of systems with linear response. The conclusions therefore apply to Hall, piezoresistive stress, and temperature sensors, among others. During the calibration procedure, well-controlled measurand values need indeed to be applied to the system; however, while all disturbance parameters need to be varied during calibration, accurate knowledge of their values is not needed. By making use exclusively of the calibration measurand values and the concurrently extracted sensor signals, it is possible to determine a reduced calibration matrix which ensure the successful extraction of disturbance-compensated measurand values from sensor signals. The effectiveness of the method is demonstrated using a six-degree-of freedom linear force-moment microtransducer with redundant sensors. The method may save cost by simpler calibration setups and the time-saving procedure it proposes. [ABSTRACT FROM AUTHOR]

This paper presents study of design, modelling, and analysis of a modified octagonal ring based cutting force measuring transducer. The shape of an octagonal ring was modified by altering the geometry of the circle into an ellipse. The main objective is to increase the strain to the displacement ratio under a given load so that the sensitivity is maximized. Analytical and three-dimensional (3D) finite element (FE) methods were deployed to estimate mechanical responses such as strain, displacement, and stress of the transducer. Results showed that compared to the octagonal ring with circle, the modified octagonal ring with ellipse had maximized the sensitivity by 15% and 25% in axial and tangential loading, respectively. In order to assess the performance of the designed transducer, calibration tests were performed on an Instron machine under axial and tangential loading and cross-sensitivity of force measurements was analysed. Following the ISO 376:2011 standard, an extensive uncertainty evaluation was performed to validate the measurement process used in the calibration. Calibration results showed that the force transducer with the proposed octagonal–ellipse ring was able to measure the force with average error less than 2%. The maximum average error in cross-sensitivity is found to be less than 5% while the overall uncertainty in measurements was up to 1.78%. Based on simulation and calibration test results, the position and the orientation of the strain gauges on the transducer were determined, and a new and compact layout of the 3D cutting force measurement system for milling was then designed and modelled. A frequency analysis was performed to assess the vibrational response of the system. It is expected that the transducer integrated with octagonal–ellipse rings would potentially be a sustainable and cheaper option for small-to-medium sized workshops to accurately measure the milling forces. [ABSTRACT FROM AUTHOR]

The influence of modification of MF-4SC membranes with silica (or surface-hydrophobized silica) nanoparticles on their ionic conductivity and diffusion permeability as well as the response stability and sensitivity of the membrane-based DP-sensors for cations of amino acids containing hydrophobic fragment has been studied. The membranes modified with surface-hydrophobized silica exhibited the 2-5 times reduced relative error of determination of the hydrophobic amino acids as compared to the initial membranes. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO 2) sensor has a wide range of applications in many industrial fields. However, most existing CO 2 sensors exhibit obvious cross-sensitivity to environmental relative humidity (RH). Therefore, it becomes critical for CO 2 sensors to eliminate the interference of humidity. In this study, based on the advantages of conveniently constructing sensing network and multiplexing capability of FBGs, the combination of polyimide-coated fiber Bragg gratings (FBGs) and etched FBGs sensors with different sensitivities was proposed to detect the concentration of CO 2 and humidity levels simultaneously. Two sets of sensors were fabricated by changing the coating thickness and etching the grating region, respectively. The experimental results indicate that all the sensors have a good linear response to CO 2 and humidity, as well as excellent response reversibility and repeatability. The highest sensitivity of the sensors towards CO 2 was 0.585 με/vol% CO 2 , while 4.191 με/% RH towards humidity. The CO 2 +RH mixture exposure experiments were carried out to demonstrate the feasibility of simultaneous detection of CO 2 and humidity levels, which showed small deviations between the detected and set values of CO 2 concentrations and humidity levels. Moreover, the fabricated sensors can operate over a wide range of temperatures. • Simultaneous detection of CO 2 concentrations and humidity levels. • Good selectivity, reversibility and repeatability. • Quantified detection of a wide range of CO 2 concentrations and humidity levels. • Sensors can operate over a wide range of temperature. [ABSTRACT FROM AUTHOR]

Realization of highly selective and sensitive sensors for various emission gases at higher temperatures is a demanding task of combustion related applications. One of the challenges in meeting these requirements is to develop nano-structured and smart functional materials to detect and monitor emission gases selectively. This work describes the functionalization of TiO 2 -nanotubular layers for NO 2 -sensing through homogeneously distribution of Cr 3+ -doping. Fully incorporation of Cr into the TiO 2 lattice has been demonstrated by TEM, XPS and XRD analysis. No other oxide phase separation occurred even after annealing at temperatures up to 700 °C. By Cr-incorporation into the lattice, TiO 2 -NTs display p-type semiconducting sensing behaviour. As small as 2.5% Cr-doping of TiO 2 -NTs results in improvement of the high-temperature NO 2 -sensing capability in the temperature range of 300–500 °C and in concentrations between 25 and 100 ppm. Furthermore, the cross-sensitivity to CO has been reduced by doping as demonstrated during the mixed gas detection of NO 2 . [ABSTRACT FROM AUTHOR]

The resistance of several models of catalytic, workfunction-based metal-oxide-semiconductor and electrochemical hydrogen sensors to chemical contaminants such as SO 2, H 2 S, NO 2 and hexamethyldisiloxane (HMDS) has been investigated. These sensor platforms are among the most commonly used for the detection of hydrogen. The evaluation protocols were based on the methods recommended in the ISO 26142:2010 standard. Permanent alteration of the sensor response to the target analyte (H 2 ) following exposure to potential poisons at the concentrations specified in ISO 26142 was rarely observed. Although a shift in the baseline response was often observed during exposure to the potential poisons, only in a few cases did this shift persist after removal of the contaminants. Overall, the resistance of the sensors to poisoning was good. However, a change in sensitivity to hydrogen was observed in the electrochemical platform after exposure to NO 2 and for a catalytic sensor during exposure to SO 2 . The siloxane resistance test prescribed in ISO 26142, based on exposure to 10 ppm HMDS, may possibly not properly reflect sensor robustness to siloxanes. Further evaluation of the resistance of sensors to other Si-based contaminants and other exposure profiles (e.g., concentration, exposure times) is needed. [ABSTRACT FROM AUTHOR]

Objective The extent to which adverse cognitive effects (ACEs) to a specific antiepileptic drug (AED) affect the chance of developing ACEs to other AEDs (i.e., cross-sensitivity) is unknown. We investigated the rates of cross-sensitivity of ACEs among AEDs and examined the association between clinical characteristics and occurrence of having ACEs to multiple AEDs in adults with epilepsy. Methods The rates of cross-sensitivity of intolerable ACEs (IACEs; i.e., ACEs leading to dosage reduction or discontinuation) and the non-AED predictors of IACEs were investigated in 2269 patients who had taken at least two AEDs at a single center. We accounted for AED load and looked for specific cross-sensitivities between AEDs as well as cross-sensitivity based on the AED mechanism of action. Results Among the 2269 patients, the highest rates of IACEs were seen with TPM (26.3%), ZNS (9.8%), PHT (8.8%), and VPA (8.5%). Intolerable ACEs to two or more AEDs occurred in 100 patients (4.4%). History of psychiatric condition(s) and absence seizure type were independent predictors of IACEs to two or more AEDs. High rates of cross-sensitivity of IACEs were seen between phenytoin (PHT) and lamotrigine (LTG), valproate (VPA) and phenytoin, and valproate and zonisamide (ZNS). For example, of patients who had IACEs to VPA and were also prescribed ZNS, 46.2% had IACEs to ZNS (abbreviated as VPA → ZNS: 46.2%); of patients who had IACEs to ZNS and were also prescribed VPA, 37.5% had IACEs to VPA (abbreviated as ZNS → VPA: 37.5%). Other results are as follows: LTG → PHT: 28.6%, PHT → LTG: 20.0%, PHT → VPA: 42.9%, and VPA → PHT: 27.3%. No specific cross-sensitivities were found among AEDs sharing a similar mechanism of action. Significance The probability of ACE intolerability to an AED can increase if a patient developed ACE intolerability to another AED. The cross-sensitivity rates for ACE intolerability between LTG and PHT, PHT and VPA, and VPA and ZNS were found to be particularly high. The cross-sensitivity rates provided here may be clinically useful for predicting ACE intolerability in patients taking certain AEDs and for AED selection in individual patients. [ABSTRACT FROM AUTHOR]

Cross-sensitive DP-sensors based on perfluorinated sulfonated cation-exchange membranes containing hydrated ZrO nanoparticles are used for the simultaneous determination of NovH, LidH, and K ions in aqueous solutions. A significant increase in the sensitivity of DP-sensors to NovH and LidH in solutions of NovHCl + LidHCl, NovHCl + KCl, and LidHCl + KCl compared to sensitivity to HO ions interfering with the determination of corresponding organic cations is achieved by varying the concentration of ZrO in the membranes. [ABSTRACT FROM AUTHOR]

The concatenated strong fiber Bragg grating and a weak long period grating are presented for simultaneous temperature and solution concentration measurement in the methods of both detailed coupled-mode theory and experimental analysis, and find two ways which include dual wavelength method and dual parameter method to solve the cross sensitivity problem to ensure higher accuracy and sensitivity. Two peaks appear in reflection spectrum of CLBG device, and the higher peak is determined by FBG while the other peak is influenced by FBG and LPG. Temperature and solution concentration are adopted to test the performance of multi-parameter sensing simultaneously. By comparing two schemes, using wavelength shifts of the two peaks may solve the cross-sensitivity problem, but its resolution is still very low. Here, another scheme based on light intensity changes and wavelength shifts of the two peaks in reflection spectrum is designed to improve the resolution further. Experiment result proves that the resolution of the proposed method is higher than that of the improved way, and the CLBG device keeps higher sensitivity with our proposed method. [ABSTRACT FROM AUTHOR]

Material surface - analyte interactions play important roles in numerous surface mediated processes including gas sensing. However, effects of topological polar surface area (TPSA) of target analytes on surface interactions during gas sensing have been so far largely disregarded. In this work, based on experimental observations on cross-sensitivity in cadmium sulfide (CdS) nanoparticle based room temperature gas sensor, we found that for reactions with similar Energy Rate of Surface Interaction (ERSI), unexpected quadratic correlation exists between sensing response of CdS and TPSA of analytes. From general understanding and as reported earlier in case of drug absorption through surface of membranes, it is expected that surface interactions would decrease with increasing TPSA of analytes. Our results imply that for certain TPSA range, sensor surface-analyte interactions actually increase with increasing TPSA before it finally starts decreasing. Further experiments on four other diverse material systems like AlN, SnO 2 , TiO 2 (Anatase) and Vanadium-doped SnO 2 showed similar trend, revealing generalized picture of TPSA dependence of sensor surface-analyte interactions. A physical explanation behind the parabolic relation has been provided based on electrostatic energy minimization of interacting polar fields. Above finding is anticipated to pave way to achieve improved surface interactions and highly selective sensing performances consecutively. [Display omitted] • Cross-sensitivity studies on metal oxide, nitride and sulfide based chemiresistors. • Topological Polar Surface Area (TPSA) of analytes affects sensor selectivity and sensitivity. • Parabolic correlation between sensing response and TPSA has been identified. • Parabolic correlation to tailor highly active and selective functional surfaces. • Extension of the parabolic correlation to other surface mediated phenomena. [ABSTRACT FROM AUTHOR]

The development of reliable hydrogen sensors is crucial for the safe use of hydrogen. One of the main concerns of end users is sensor reliability in the presence of species other than the target gas, which can lead to false alarms or undetected harmful situations. To assess the selectivity of commercial-off-the-shelf hydrogen sensors, a number of sensors of different technology types were exposed to various interferent gas species. Cross-sensitivity tests were performed in accordance with the recommendations of ISO 26142:2010, using the hydrogen sensor testing facilities of the National Renewable Energy Laboratory and the Joint Research Centre – Institute for Energy and Transport. Most of the sensor platform tested are unaffected by the exposure to the interferents. The metal-oxide and the thermal conductivity platform show a remarkable sensitivity to CH 4 . None of the platforms tested were permanently affected by the exposure to the cross-sensitive species. [ABSTRACT FROM AUTHOR]

Highlights: [•] Highly sensitive, low temperature butane sensing characteristics of lanthanum ferrite nano-crystals are explained to be due to their catalytic activity toward butane oxidation. [•] The catalytic activity is hypothesized to be due to the presence of surface adsorbed oxygen species and hydroxyl ions on sensor surface. [•] The selectivity coefficients for lanthanum ferrite butane sensors were estimated to be 1.67 and 4.67 for 50ppm hydrogen and carbon monoxide sensing respectively. [•] Principal component analysis is demonstrated to be fruitful to address the cross-sensitivity of these sensors. [Copyright &y& Elsevier]

Highlights: [•] The impact of using a NO x sensor-cross sensitive to NH3 for SCR control purposes is explained in this paper. [•] A control model obtained by singular perturbation is proposed. [•] A control strategy is presented and the closed loop equilibria is studied in details. [•] The performances of the strategy are given under real driving conditions. [Copyright &y& Elsevier]

Non-dispersive infrared CO2/H2O gas analysers produce erroneous CO2 outputs when CO2 is measured in humid air, unless a correction for water vapour cross-sensitivity is applied. Spectroscopic cross-sensitivities arising from direct absorption interference and from the pressure broadening effect are significant in CO2 flux measurements by the eddy covariance technique using open-path gas analysers over the ocean, as opposed to land-surface measurements, where CO2 fluxes are orders of magnitude larger. In this study, a widely used analyser with manufacturer-determined correction coefficients for both cross-sensitivities was tested by laboratory experiments. Our results showed that the correction coefficient for direct absorption interference was not optimised to calculate CO2 flux accurately, and that the correction coefficient for the pressure broadening caused overestimation of the CO2 mixing ratio flux in the same direction as the water vapour flux. Overestimations of open-path eddy covariance measurements of upward CO2 fluxes in previous ocean observations probably resulted from inaccuracies in both of these correction coefficients. We also found that slight changes in spectroscopic cross-sensitivities due to contamination of the analyser's optical windows by sea salt caused a low bias in CO2 outputs with increasing H2O; however, this contamination effect was not always observed in repeated tests under different contamination conditions. We suggest that previously proposed methods for correcting the effect of optical window contamination is of limited value and that measurement of small CO2 fluxes by the open-path eddy covariance technique over the ocean should be performed after confirming the spectroscopic cross-sensitivity and ensuring that the optical windows are as clean as possible. [ABSTRACT FROM AUTHOR]

Based on the analysis of a typical configuration of piezoresistive sensors, the intensity and uniformity of stresses produced by measurand force in the piezoresistive elements are identified as the parameters that affect the sensitivity of a sensor, and stresses produced by perturbation forces in the piezoresistive elements are identified as the parameters that affect the cross-sensitivity of a sensor. To maximize sensitivity and minimize cross-sensitivity, a shape and topology optimization problem is formulated to tailor the stresses in a local region where the piezoresistive elements are placed. In the optimization, the measurand force and perturbation forces are considered separately as two load cases. The optimization problem is solved via the level set based method. Numerical examples in two dimensions are investigated. [ABSTRACT FROM AUTHOR]

The air-sea $$\text{ CO }_{2}$$ flux was measured from a research vessel in the North Yellow Sea in October 2007 using an open-path eddy-covariance technique. In 11 out of 64 samples, the normalized spectra of scalars ( $$\text{ CO }_{2}$$, water vapour, and temperature) showed similarities. However, in the remaining samples, the normalized $$\text{ CO }_{2}$$ spectra were observed to be greater than those of water vapour and temperature at low frequencies. In this paper, the noise due to cross-sensitivity was identified through a combination of intercomparisons among the normalized spectra of three scalars and additional analyses. Upon examination, the cross-sensitivity noise appeared to be mainly present at frequencies $${<}0.8\,\text{ Hz }$$. Our analysis also suggested that the high-frequency fluctuations of $$\text{ CO }_{2}$$ concentration (frequency $${>}0.8\,\text{ Hz }$$) was probably less affected by the cross-sensitivity. To circumvent the cross-sensitivity issue, the cospectrum in the high-frequency range 0.8-1.5 Hz, instead of the whole range, was used to estimate the $$\text{ CO }_{2}$$ flux by taking the contribution of the high frequency to the $$\text{ CO }_{2}$$ flux to be the same as the contribution to the water vapour flux. The estimated air-sea $$\text{ CO }_{2}$$ flux in the North Yellow Sea was $$-0.039\,\pm \,0.048\,\text{ mg } \text{ m }^{-2}\,\text{ s }^{-1},$$ a value comparable to the estimates using the inertial dissipation method and Edson's method (Edson et al., J Geophys Res 116:C00F10, ). [ABSTRACT FROM AUTHOR]

Due to advantages such as light weight, flexibility, and low cost, polyvinylidene fluoride (PVDF) films have been widely used in engineering applications as sensors for detecting strain, pressure, or micro-force. However, it is known that PVDF strain sensors have strain cross-sensitivity in mutually orthogonal directions. Furthermore, the size of the PVDF film sensor would also affect the dynamic strain sensing performance. In this paper, to investigate the cross-sensitivity and size effects experimentally, we employ PVDF film sensors to perform dynamic measurements on a cantilever beam. Since the vibrations of the cantilever beam are excited by impacts of a steel ball, the induced highly repeatable transient responses contain a wide range of resonant frequencies and thus can be used to investigate both the size and cross-sensitivity effects of the PVDF film sensors in a dynamic sensing environment. Based on the experimental results of the identified resonant frequencies compared with results obtained from a strain gauge, finite element calculations, and theoretical predictions, suggestions for the use of the PVDF strain sensor in modal testing are given in this paper. [ABSTRACT FROM AUTHOR]

Abstract: High-dimensional data are always a great challenge for post-processing. This paper proposed a new computational model for dimensionality reduction toward the huge data sampled from the multi-sensor array in voltammetric electronic tongue. It employs a linear superposition model of noise for a set of basis functions to describe the serial current responses of cross-sensitive multi-sensor array. And the coefficients of the basis function set, with a much lower dimensionality, are used as the reduced feature data for a sample. More importantly, the values of those coefficients show high consistency with the responses of electrodes, namely, larger currents measured may result in greater coefficient values, and vice versa. According to the theoretical analysis and practical results of the experiments, besides the value-consistency which is never supported by existing approaches, the proposed model also performs very well in the three key factors for evaluating an approach to dimensionality reduction (i.e. reduction rate, reconstruction error, and complexity): (1) strong ability in dimensionality reduction and feature preservation—the reduction rate reaches as high as circa 280–420, and the average reconstruction error is circa 1–5%; (2) linear time complexity—it is applicable to most huge datasets. [Copyright &y& Elsevier]

Background & Aims: Multiple instances of DILI in the same patient with drugs of similar structure or function as well as completely unrelated drugs are not well understood and poorly documented. We have sought evidence of the frequency and characteristics of patients who have experienced two DILI episodes due to different drugs. Methods: All cases of DILI systematically collected in the Spanish DILI Registry between 1994 and 2009 were retrieved. Data on demographics, clinical, laboratory and pathological findings, and outcome were analyzed. Results: Nine patients (mean age 67years, four women) out of 742, 1.21%, had evidence of two DILI episodes caused by different drugs. In four cases DILI was associated with structurally related drugs and in an additional two cases the drugs had a common target. In another case, unrelated antibiotics were implicated. In only two cases, the two drugs/herbals were not related in structure or function. All but one patient exhibited hepatocellular damage. The type of damage was consistent in both DILI episodes. Four cases presented as autoimmune hepatitis (AIH) in the second episode. Conclusions: Multiple episodes of DILI in association with different drugs occur infrequently. In each individual, the type of injury was similar during the two DILI episodes, regardless of the causative drug. Second episodes of DILI are more likely to be associated with features of AIH. It remains uncertain if this is drug-induced unmasking of true AIH or DILI with autoimmune features. These cases illustrate the dilemma faced by clinicians in distinguishing these possibilities. [Copyright &y& Elsevier]

Abstract: This paper describes an optical sensor for the monitoring of ammonia gas. An open path optical technique is used to analyze the absorption lines of ammonia within the ultra-violet region. The optical sensor shows absorption lines comparable to the theoretical ammonia spectra. Cross-sensitivity with carbon dioxide and oxygen gas has been tested and clearly shows that these two gases have no effect on ammonia measurement in the ultra-violet region, between 200nm and 230nm. The optical sensor is able to detect ammonia down to 9ppm with an average error less than 2%. The optical sensor system also shows a fast response time which is less than 4s. [Copyright &y& Elsevier]

Abstract: ZnO coated one-port surface acoustic wave (SAW) resonators are used as ammonia sensor in the present study. The cross-sensitivity of the sensor with commonly available volatile organic compounds (VOCs)/gases has been analyzed. An interesting feature through which the presence of ammonia can be differentiated from rest of the vapors/gases has been observed. The differential frequency shift (Δf) of the sensor is positive for liquor ammonia and negative for the rest. Further Δf for ammonia in the presence of water vapors is found to be positive. The sensor has good sensitivity, selectivity, reversibility and repeatability. The results are analyzed by considering possible sensing mechanisms such as electrical loading, elastic loading and mass loading. The results suggest the possibility of utilizing the ZnO coated sensor for the efficient selective detection of ammonia. [Copyright &y& Elsevier]

Abstract: The cross-sensitivity of chemical sensors for several metal ions resembles in a way the overlapping sensitivity of some biological sensors, like the optical colour receptors of human retinal cone cells. While it is difficult to assign crisp classification values to measurands based on complex overlapping sensory signals, fuzzy logic offers a possibility to mathematically model such systems. Current work goes into the direction of mixed heavy metal solutions and the combination of fuzzy logic with heavy metal-sensitive, silicon-based chemical sensors for training scenarios of arbitrary sensor/probe combinations in terms of an electronic tongue. Heavy metals play an important role in environmental analysis. As trace elements as well as water impurities released from industrial processes they occur in the environment. In this work, the development of a new fuzzy logic method based on potentiometric measurements performed with three different miniaturised chalcogenide glass sensors in different heavy metal solutions will be presented. The critical validation of the developed fuzzy logic program will be demonstrated by means of measurements in unknown single- and multi-component heavy metal solutions. Limitations of this program and a comparison between calculated and expected values in terms of analyte composition and heavy metal ion concentration will be shown and discussed. [Copyright &y& Elsevier]