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Screen-printed electrodes (SPEs) are ubiquitous within the field of electrochemistry and are commonplace within the arsenal of electrochemists. Their popularity stems from their reproducibility, versatility, and extremely low-cost production, allowing their utilization as single-shot electrodes and thus removing the need for tedious electrode pretreatments. Many SPE studies have explored changing the working electrode composition and/or size to benefit the researcher's specific applications. In this paper, we explore a critical parameter of SPEs that is often overlooked; namely, we explore changing the length of the SPE connections. We provide evidence of resistance changes through altering the connection length to the working electrode through theoretical calculations, multimeter measurements, and electrochemical impedance spectroscopy (EIS). We demonstrate that changing the physical length of SPE connections gives rise to more accurate heterogeneous electrode kinetics, which cannot be overcome simply through IR compensation. Significant improvements are observed when utilized as the basis of electrochemical sensing platforms for sodium nitrite, β-nicotinamide adenine dinucleotide (NADH), and lead (II). This work has a significant impact upon the field of SPEs and highlights the need for researchers to characterize and define their specific electrode performance. Without such fundamental characterization as the length and resistance of the SPE used, direct comparisons between two different systems for similar applications are obsolete. We therefore suggest that, when using SPEs in the future, experimentalists report the length of the working electrode connection alongside the measured resistance (multimeter or EIS) to facilitate this standardization across the field.

Satellite-derived land surface temperatures (LSTs) are a critical parameter in various fields. Unfortunately, there are numerous gaps in LST products due to cloud contamination and orbital gaps. In previous studies, various gapfilling methods have been developed. However, most of those methods use only spatiotemporal information to fill gaps. In this study, a gapfilling method called the enhanced hybrid (EH) method that integrates spatiotemporal information and information from other similar LST products was proposed. The accuracy of the EH method was compared with the accuracies of three other gapfilling methods that only use spatiotemporal information: Remotely Sensed DAily land Surface Temperature reconstruction (RSDAST), interpolation of the mean anomalies (IMAs), and Gapfill. It was found that the correlations between the four LST products were strong, indicating that using information from other products may improve the accuracy of gapfilling. On average, the mean absolute errors (MAEs) of the data filled using the EH method were 23.7%-52.7% lower than those of RSDAST, 35.4%-38.7% lower than those of IMA, and 38.5%-46.9% lower than those of the Gapfill method. The usage of information from other similar LST products was the main reason for the high accuracy observed for the EH method. In addition, the LST images filled using the RSDAST and IMA methods had some outliers, while there were fewer obvious outliers in the LST images filled with the EH method. It was concluded that the EH method is a robust gapfilling method with a high accuracy.

Self-centering rocking shear wall (SCRSW) is an innovative structural system which is designed to achieve low damage after strong earthquake shaking. In this paper, an effective damage quantification method is developed to quantify the damages of SCRSWs. The procedure is applied in the performance evaluation and damage quantification for 24 SCRSWs. An equation of the critical parameter β in the damage model is proposed. The results show that increasing stirrup reinforcement ratio, self-centering parameter and concrete strength can reduce the damage developed in SCRSWs effectively, while higher prestress in post-tensioned (PT) tendons tends to increase the damage. An empirical equation between the critical parameter β and structural features is proposed. The critical parameter is then used to quantify the damage index (DI) of SCRSW. The result shows that the proposed β can be used to evaluate and quantify the damages developed in SCRSWs efficiently and accurately.

Design of connections in mass timber are critical. Mass plywood panels (MPP) are a relatively new mass timber product, therefore, only a few studies characterizing their mechanical and connection properties exist. Dowel bearing strength is a critical parameter required in connection design regardless of the complexity of the connection. This study investigated the dowel bearing strength of MPP under the effect of exposure to elevated temperature. Thirty-two exposure duration-temperature combination was tested along with control group. Two analytical models are developed to explain the thermal degradation, one assuming a mechanism based on first-order kinetics and the second using a statistical regression. The degradation in the dowel bearing strength with respect to the increase in time and temperature exposure was characterized. In general, the kinetics model seemed to explain the data better than MLR using one less parameter.

Motivation The acid dissociation constant (pKa) is a critical parameter to reflect the ionization ability of chemical compounds and is widely applied in a variety of industries. However, the experimental determination of pKa is intricate and time-consuming, especially for the exact determination of micro-pKa information at the atomic level. Hence, a fast and accurate prediction of pKa values of chemical compounds is of broad interest. Results Here, we compiled a large-scale pKa dataset containing 16 595 compounds with 17 489 pKa values. Based on this dataset, a novel pKa prediction model, named Graph-pKa, was established using graph neural networks. Graph-pKa performed well on the prediction of macro-pKa values, with a mean absolute error around 0.55 and a coefficient of determination around 0.92 on the test dataset. Furthermore, combining multi-instance learning, Graph-pKa was also able to automatically deconvolute the predicted macro-pKa into discrete micro-pKa values. Availability and implementation The Graph-pKa model is now freely accessible via a web-based interface (https://pka.simm.ac.cn/). Supplementary information Supplementary data are available at Bioinformatics online.

In the present study, an analytical model was proposed to predict the fatigue response of damaged beams strengthened with ground granulated blast-furnace slag (GGBS) based ultra-high performance concrete (UHPC) strips. The proposed analytical fatigue prediction model (FPM) incorporated with fatigue properties of constituent materials and cross-sectional stress analysis of composite reinforced concrete (RC) beams subjected to fatigue loading condition. The critical parameter controlling the fatigue behaviour of damaged beams strengthened with UHPC strips were a degree of damage in the reinforcing bars and thickness of GGBS based UHPC strips (5, 10 and 15 mm). The damage incorporated in the FPM was categorised as mild, severe and very severe based on the degree of damage level (0.2, 0.3 and 0.7, respectively). In the FPM, fatigue response of strengthened RC beams was captured at the end of each stage of fatigue cycle and updating the material properties iteratively until the threshold of constituent material was attained. From the FPM results, strengthening with a thin UHPC strip (5 mm) was effectively restored the fatigue performance of RC beams induced with a very severe degree of damage level. The analytical studies carried out in the present study were validated with the author’s previous experimental investigation. The maximum deviation in predicted results between the experiments and the FPM was 16, 28 and 12% for mild, severe and very severely damaged beams, respectively.

Ground vibrations induced during rock fragmentation by blasting remain a potential source of hazard for the stability of nearby structures. In this paper, to forecast the effect of blast-induced ground vibrations, dimensional analysis (DA) is proposed to predict peak particle velocity (PPV). In conventional predictor equations, the major and critical parameter for the estimation of PPV is square root scaled distance. The new formula based on DA was obtained considering various blast design parameters in order to improve the capability of PPV prediction. After obtaining the new DA equation for the prediction of PPV, 360 data sets were used to determine the unknown coefficients of the new equation as well as site constants of different conventional predictor equations. Then, ten additional randomly selected data sets were used to compare the capability of the new model with conventional predictor equations. The results were compared based on coefficient of determination (R2) and mean absolute error (MAE) between measured and predicted values of PPV. The proposed formula with the greatest R2 and the lowest MAE was the better option for predicting the PPV of induced vibrations for the measured field data.

Energy release from the decay of radionuclides in nuclear fuel after its discharge from reactor is a critical parameter for design, safety, and licensing analyses of used nuclear fuel storage, tran...

Knowing how small a violation of stochastic dominance rules would be accepted by most individuals is a prerequisite to applying almost stochastic dominance criteria. Unlike previous laboratory-experimental studies, this paper estimates an acceptable violation of stochastic dominance rules with 939,690 real world data observations on a choice of deductibles in automobile theft insurance. We find that, for all policyholders in the sample who optimally chose a low deductible, the upper bound estimate of the acceptable violation ratio is 0.0014, which is close to zero. On the other hand, considering that most decision makers, such as 99% (95%) of the policyholders in the sample, optimally chose the low deductible, the upper bound estimate of the acceptable violation ratio is 0.0405 (0.0732). Our results provide reference values for the acceptable violation ratio for applying almost stochastic dominance rules. This paper was accepted by Manel Baucells, decision analysis.

In a non-emulative precast shear wall structures, joints are the key to influence the overall mechanical performance under seismic actions. While wet joints are widely used in the precast reinforced concrete shear wall structure, they present problems such as collision of steel bars, inconsistency of the post-casting area and importantly, they cannot achieve the best potential of precast concrete structures. Hence, this paper proposes a new dry joint, which is a bolted C-shaped steel plate for the horizontal joint of precast shear walls. Four identical sub-assembly precast shear wall panels bolted with four distinct configurations of steel plates (plain, X-stiffeners, horizontal slots and vertical slots) were tested under reversed cyclic loading. It was discovered that the bolted steel plate with horizontal slots could improve the ductility and energy dissipation of the joint. Numerical models were calibrated by benchmarking with the experimental results. Through a systematic parametric study on the number and spacing of slots, thickness of steel plates and number of bolts, the results indicated that the number of bolts is the critical parameter that will affect initial stiffness, peak strength capacity and ductility of the proposed joint.

Weight of a railway vehicle is a critical parameter which affects the operation of it. The conventional method to monitor the weight of a railway vehicle is based on placing several sensors to the substructure. This substructure based approach does not provide a continuous monitoring. In this study, a vehicle based method, which considers the use of velocity sensors mounted on a vehicle, is proposed for this purpose. It includes the use of a mathematical model of the vehicle and a joint unscented Kalman filter. Methodology has been tested based on the measurements obtained from a full scale wheel on roller type test rig which represents the structure of some trams produced in Czechia with independently rotating wheels. This indirect estimation method reveals that use of models along with a state and parameter filter improves the accuracy of the results. This approach allows continuous monitoring of the weight (or normal load) of a vehicle just with speed sensors. As well as continuous monitoring, this methodology does not require design and implementation of specially designed sensors that should be mounted to vehicle for same purpose.

Advanced GaN power devices are promising for many applications in high power electronics but performance limitations due to material quality in etched-and-regrown junctions prevent their widespread use. Carrier diffusion length is a critical parameter that not only determines device performance but is also a diagnostic of material quality. Here we present the use of electron-beam induced current to measure carrier diffusion lengths in continuously grown and etched-and-regrown GaN pin diodes as models for interfaces in more complex devices. Variations in the quality of the etched-and-regrown junctions are observed and shown to be due to the degradation of the n-type material. We observe an etched-and-regrown junction with properties comparable to a continuously grown junction.

In an attempt to reduce environmental impact, paper sludge ash (PS ash) has recently been studied for its complementary reuse with cement for soil stabilization. In order to establish the optimal mixture design for combining PS ash and cement in soils, a detailed investigation into the stabilizing mechanism is required. To assess the combined effects of PS ash and cement on the strength development of stabilized clay soil, referred to as PS ash–cement-treated clay, a new critical parameter, the unabsorbed and unretained clay-water/cement ratio W*/C, was proposed. To determine W*/C, a new testing method for evaluating the water absorption and retention performance of PS ash was developed. It was revealed that the water absorption and retention rate Wab of PS ash increased with curing time. Unconfined compression tests conducted on the PS ash–cement-treated clay with various water-cement–PS ash mixture proportions and different curing times affirmed that the strength development was fundamentally governed by the parameter W*/C. This suggests that the water absorption and retention rate Wab obtained by the developed method is an essential material parameter in the mixture design for the PS ash–cement-treated clay. It was also found that the effect of the hybrid treatment method, which uses both cement and PS ash, was better than that of the method which uses cement alone, particularly under high W*/C conditions. This indicates that the water absorption and retention performance of PS ash can be fully utilized when the mixture has sufficient unabsorbed and unretained water for cement hydration.

Isocitrate dehydrogenase 1 and 2 mutations are known to be early events in gliomagenesis and have a definite role in tumor progression.Isocitrate dehydrogenase1/2 mutation status is considered to be one of the most powerful independent positive predictor of outcome amongst all molecular markers described in association with gliomas. The inclusion of this parameter in the 2016 update of the World Health Organization Classification of Tumors of The Central Nervous System reinforced its importance in glioma classification and prognostication. As a result, now there is enough evidence to prove that Isocitrate dehydrogenase-mutant and Isocitrate dehydrogenase- wildtypegliomas are two biologically distinct categories of gliomas with likely different pathways of tumorigenesis, different clinical outcomes, and respond differently to similar treatment strategies. Increasing knowledge aboutthe role of IDH1/2 mutation in gliomagenesis has resulted in many novel targeting strategies being developed and evaluated forusefulness in the clinical setting. This literature review aims to highlight the diagnostic and prognostic importance of Isocitrate dehydrogenase1/2 gene mutations in adult gliomas.

Various applications in science and engineering depend upon computing real solutions to systems of analytic equations which depend upon real parameters. Locally in the parameter space, the qualitative behavior of the solutions remains the same except at critical parameter values. This article develops a singular value homotopy that aims to compute critical parameter values. Several examples are presented including computing critical parameter values for nonlinear boundary value problems, turning points for a steady-state system connected to learning and memory, and computing the maximum Gaussian curvature of a surface.

Quantitative blood pressure measurement is a critical parameter for assessing cardiovascular health, monitoring physiologic status under anesthesia, and making clinical decisions. The placement of an arterial catheter is the most accurate way to measure blood pressure, but is invasive and perhaps uncomfortable for the patient, requires sedation or anesthesia, and is technically challenging for staff. Noninvasive devices and methods, including oscillometry, high-definition oscillometry, and Doppler flow can be used to measure blood pressure. However, the American College of Veterinary Internal Medicine guidelines state that blood pressure should be measured using devices that have been validated in the species of interest and under the circumstances in which the measurement is being made. The alternatives listed above have not been validated in this manner. The objective of this study was to compare indirect ultrasonic Doppler flow detection and oscillometric blood pressure measures with direct arterial measurement in 8 healthy, anesthetized African green monkeys using the methods of Bland-Altman to assess agreement. Our results indicated that neither Doppler flow nor oscillometry consistently estimates direct blood pressure measurements in anesthetized African green monkeys. In 6 female monkeys, which weighed less than the 2 male subjects, the indirect Doppler measurement more closely predicted direct mean arterial pressure, indicating Dop- pler flow may be useful for monitoring mean arterial pressure in small patients.

Water/cement (w/c) ratio is a critical parameter for the wet deep mixing method. In Singapore, a relatively high w/c ratio of 1.0–1.2 is typically used , which may reduce the performance of the cem...

The multi-level microstructure of conjugated polymers is the most critical parameter determining the charge transport property in field-effect transistors (FETs). However, controlling the hierarchical microstructures and the structural evolution remains a significant challenge. In this perspective, we discuss the key aspects of multi-level microstructures of conjugated polymers towards high-performance FETs. We highlight the recent progress in the molecular structures, solution-state aggregation, and polymer crystal structures, representing the multi-level microstructures of conjugated polymers. By tuning polymer hierarchical microstructures, we attempt to provide several guidelines for developing high-performance polymer FETs and polymer electronics., The multi-level microstructures of conjugated polymers, including solution-state aggregation and crystal structures, are reviewed due to their influence on charge transport in polymer field-effect transistors.

Excavations in shallow depth and the presence of weak overlying rock may disturb the strata conditions due to which caving start and creates a cavity in the subsurface and finally sinkhole. In central India, the sinkhole phenomenon is common in some of the coal mines and its urgent need to understand the influence of critical parameters that directly or indirectly aggravates the sinkholes. Seeing the potential damages against its occurrence, the field investigation were planned and implemented in some of the coal mines at Central India. Based on the field investigations, the detailed parametric analysis was done with respect to sinkhole depth against each critical parameter. A sinkhole model has been developed by using statistical approach to understand the collective influence of all critical parameters.

pH is a critical parameter that has found unique application in magnetic resonance imaging (MRI) mapping acidity in tissues. This study reports a series of Dy-based MR probes that show innovative T2ex features, governed by proton catalyzed events. With an increase of pH from 5.5 to 8.0, the r2ex relaxivity increased dramatically, while the r1 relaxivity remained unchanged. The resulting r2ex/r1 allowed for concentration-independent and direct mapping of physiologically relevant pH ranges.

Metagenomics is a powerful tool to identify novel or unexpected pathogens, since it is generic and relatively unbiased. The limit of detection (LOD) is a critical parameter for the routine application of methods in the clinical diagnostic context. Although attempts for the determination of LODs for metagenomics next-generation sequencing (mNGS) have been made previously, these were only applicable for specific target species in defined samples matrices. Therefore, we developed and validated a generalized probability-based model to assess the sample-specific LOD of mNGS experiments (LODmNGS). Initial rarefaction analyses with datasets of Borna disease virus 1 human encephalitis cases revealed a stochastic behavior of virus read detection. Based on this, we transformed the Bernoulli formula to predict the minimal necessary dataset size to detect one virus read with a probability of 99%. We validated the formula with 30 datasets from diseased individuals, resulting in an accuracy of 99.1% and an average of 4.5 ± 0.4 viral reads found in the calculated minimal dataset size. We demonstrated by modeling the virus genome size, virus-, and total RNA-concentration that the main determinant of mNGS sensitivity is the virus-sample background ratio. The predicted LODmNGS for the respective pathogenic virus in the datasets were congruent with the virus-concentration determined by RT-qPCR. Theoretical assumptions were further confirmed by correlation analysis of mNGS and RT-qPCR data from the samples of the analyzed datasets. This approach should guide standardization of mNGS application, due to the generalized concept of LODmNGS.

In 40Ar/39Ar dating, 39ArK generated is dependent on irradiation conditions, and the accumulation fast neutron fluence is a critical parameter for 40Ar/39Ar dating. With technological advancement, especially in the ultra-low background and multicollector technology, the boundary conditions to choose irradiation conditions have been greatly improved. Based on the detected and processed signal, the maximum boundary condition of 40Ar*/39Ar can be up to 5750, meaning that very low 39Ar signals can yield considerable analytical accuracy. In this study, one biotite sample (ZBH-25) was irradiated for 4 hours to assess the modified irradiation conditions, and the high 40Ar*/39Ar ratio up to 4100 could yield ∼1% analytical uncertainty. This reveals that the new boundary condition is useful to choose fast neutron fluence, especially for very old or low K/Ca ratio samples.

The Friction Stir Welding (FSW) is a solid-state joining method. FSW can be used for comprehensive joining of sensitive materials such as aluminum (Al), copper and magnesium etc. Fusion welding is hard to connect to the alloys and their composites. The geometry of tools and equipment are the main parameters of FSW. This method relies primarily on tool elements such as the diameter of the shoulders, the angle of the shoulder surface, the tool structure with its shape and dimensions and the potential for surfaces of the equipment. Some researchers have defined cross and rotational speeds as the key process parameters for perfect welding performance. Tool geometry is a critical parameter affecting the weld quality and joint properties. The paper examines the progression of different pin profiles and their effects on the weld joint microstructure.

Sustainable hunting, the extraction of game without reducing its density, is a desirable approach to the use of wildlife. Assessment of sustainable extraction in many parts of the world is difficult; it has recently been done by a method proposed by Robinson and Redford (1991): a maximum number of animals that can be extracted per unit area is calculated based on life-history parameters and density estimates. If extraction is higher than that maximum number, it is deemed unsustainable. We extended the method by adding spatial and stochastic components through an individual-based model of a population of female tapirs ( Tapirus sp.) and conducted a sensitivity analysis to evaluate the importance of spatial and life-history parameters. Our analysis suggests that spatial factors, such as the shape of the hunted area and the size of the surrounding population, may be important in determining the sustainability of extraction. For long-lived, slow-reproducing mammals such as tapirs, survival to age of last reproduction is the most critical parameter, but the shape of the hunting zone and population density can be critical, especially in unsustainable hunting scenarios. We advocate long-term studies of tapirs to collect information on spatial movements and survival rates that could then be used for development of proper management plans. Resumen: La caceria sustentable, extraccion de animales de caza sin reduccion de su densidad, es un enfoque deseable para el uso de vida silvestre. La evaluacion de la extraccion sustentable es dificil en muchas partes del mundo y se ha hecho utilizando un metodo propuesto por Robinson y Redford (1991): el numero maximo de animales que se puede extraer por unidad de area se calcula con base en parametros de la historia de vida y estimaciones de la densidad. Si la extraccion es mayor que ese numero maximo, se considera no sustentable. Extendimos el metodo agregando componentes espaciales y estocasticos por medio del modelo basado en individuos de una poblacion de tapires ( Tapirus sp.) hembras y realizamos un analisis de sensibilidad para evaluar la importancia de los parametros espaciales y de la historia de vida. Nuestro analisis sugiere que factores espaciales, tal como la forma del area de caceria y el tamano de la poblacion circundante, pueden ser importantes en la determinacion de la sustentabilidad de la extraccion. Para especies longevas de reproduccion lenta como el tapir, la supervivencia hasta la ultima edad reproductiva es el parametro mas critico; pero la forma del area de caceria y la densidad pueden ser criticas, especialmente en poblaciones bajo caza no sustentable. Recomendamos estudios de largo plazo de tapires para obtener informacion de movimientos espaciales y tasas de supervivencia que pueda utilizarse para el desarrollo de planes de manejo adecuados.