Inaccurate Signals Research Articles

M3Sense

Modern smartwatches or wrist wearables having multiple physiological sensing modalities have emerged as a subtle way to detect different mental health conditions, such as anxiety, emotions, and stress. However, affect detection models depending on wrist sensors data often provide poor performance due to inconsistent or inaccurate signals and scarcity of labeled data representing a condition. Although learning representations based on the physiological similarities of the affective tasks offer a possibility to solve this problem, existing approaches fail to effectively generate representations that will work across these multiple tasks. Moreover, the problem becomes more challenging due to the large domain gap among these affective applications and the discrepancies among the multiple sensing modalities. We present M3Sense, a multi-task, multimodal representation learning framework that effectively learns the affect-agnostic physiological representations from limited labeled data and uses a novel domain alignment technique to utilize the unlabeled data from the other affective tasks to accurately detect these mental health conditions using wrist sensors only. We apply M3Sense to 3 mental health applications, and quantify the achieved performance boost compared to the state-of-the-art using extensive evaluations and ablation studies on publicly available and collected datasets. Moreover, we extensively investigate what combination of tasks and modalities aids in developing a robust Multitask Learning model for affect recognition. Our analysis shows that incorporating emotion detection in the learning models degrades the performance of anxiety and stress detection, whereas stress detection helps to boost the emotion detection performance. Our results also show that M3Sense provides consistent performance across all affective tasks and available modalities and also improves the performance of representation learning models on unseen affective tasks by 5% - 60%.

Detection of glutathione, cysteine, and homocysteine by online derivatization-based electrospray mass spectrometry.

Electrospray ionization mass spectrometry (ESI-MS) is one of the most popular techniques for obtaining structural information, which is commonly used in bioanalysis and clinical diagnostics. However, for the detection of complicated samples with high reactivities (such as reactive sulfur species, RSS), traditional ESI-MS usually suffers from overlapped and inaccurate signals. In this study, based on the multiphase flow of extractive electrospray ionization (MF-EESI), an ambient MS technique of online derivatization was proposed to detect thiols without any other sample pretreatment. RSS molecules and the derivatization reagent of 4-chloro-7-nitro-1,2,3-benzoxadiazole (NBD-Cl) were introduced into the internal and innermost capillary of the MF-EESI system, respectively. By a high-velocity nebulizing stream of N2 gas through an external capillary, both flows of innermost biothiols and internal NBD-Cl were electrosprayed and mixed for online reactions. Therefore, the fast derivatization of thiols was used to generate stable ionized derivatives for MS detection. By evaluating the changes in MS signals before and after the derivatization, the ions of RSS were identified simply and correctly. Without any sample pretreatment, the fast detection of cysteine, homocysteine, and glutathione has been achieved in the complicated samples. The present online derivatization-based MF-EESI was successfully used for fast, simple, and accurate detection of biothiols. This presented a potential pathway for the fast identification of thiols in complicated samples.

Recent Advances on Designs and Applications of Hydrogel Adhesives

AbstractIn virtue of extracellular features, hydrogels have been used in various areas such as tissue repair, artificial skins, and biological electronics, etc. Intact contact of tough hydrogels to targeted surfaces is usually required to avoid blood or body fluids leakage or inaccurate signals of sensors. The collaboration of high interactive energy between interfaces and high fracture toughness of the constituent hydrogels can effectively prevent relatively macroscopic motions of adhesives from substrates under deformation. Nevertheless, variations in surface microenvironment like moisture, roughness, and functional groups can lead to the scission of bonds between bulk hydrogel and surfaces. Accordingly, to prevent detachment of adhesives, specific tactics should be utilized to reach a targeted surface based on substrates’ physical and chemical properties. This review concentrates on various hydrogel adhesives in the near‐decade, from design strategies, including physical interactions, chemical bonds, and bio‐inspired ways, to eventual applications, like wound closure, sensors, soft robots, and tissue repair. Meanwhile, it is anticipated that these approaches could spur sparks for fabricating appropriate tough adhesives under different circumstances.

Design of Long‐Term Conditional Cash Transfer Program to Encourage Healthy Habits

Noncommunicable diseases (NCDs) are among the largest health emergencies nowadays. Although a large proportion of NCDs can be prevented effectively via good life habits, these remain ubiquitous and one main reason is people's self‐control problem caused by time‐inconsistent, present‐biased preferences. In this situation, we wonder whether a “long‐term” conditional cash transfer (CCT) program, which is known to be effective in shaping people's behaviors but expensive, can be a viable solution. We establish a model which can be fine‐tuned by many parameters, and show that our results are robust in a wide range of parameters. We identify the optimal CCT scheme which helps people achieve their long‐term plan while generating the lowest cash flow. Our results suggest interesting managerial insights like that the amount of necessary financial incentives can depend on people's age, and that the government's optimal CCT scheme does not depend on the level of people's naivete. Also, it is profitable for companies to hold such a program and sell enrollment to customers as self‐commitment devices. However, companies may exploit customers’ naivete to maximize their profit while hurting social welfare. We also examine situations that people's behaviors can only be monitored indirectly through inaccurate signals and that people are heterogeneous in how present‐biased they are.

Contrasting Monetary and Multidimensional Poverty Measures in a Low-Income Sub-Saharan African Country

Despite significant progress in poverty measurement, few studies have undertaken an in-depth comparison of monetary and multidimensional measures in the context of low-income countries and fewer still in Sub-Saharan Africa. Yet the differences can be particularly consequential in these settings. We address this gap by applying a distinct analytical strategy to the case of Rwanda. Using data from two waves of the Rwandan Integrated Household Living Conditions Survey, we combine comparing poverty rates cross-sectionally and over time, examining the overlaps and differences in the two measures, investigating poverty rates within population sub-groups, and estimating several statistical models to assess the differences between the two measures in identifying poverty risk factors. We find that using a monetary measure alone does not capture high incidence of multidimensional poverty in both waves, that it is possible to be multidimensional poor without being monetary poor, and that using a monetary measure alone overlooks significant change in multidimensional poverty over time. The two measures also differ in which poverty risk factors they put emphasis on. Relying only on monetary measures in low-income sub-Saharan Africa can send inaccurate signals to policymakers regarding the optimal design of social policies as well as monitoring their effectiveness.

Market diffusion of household PV systems: Insights using the Bass model and solar water heaters market data

This paper aims to present insights about distributed photovoltaic (PV) generation technology diffusion in the household market. A quantitative approach using the Bass model to project distributed PV systems adoption is chosen to base and conduct the analysis. Since distributed PV in Brazil still presents a very small market penetration, historical data is still insufficient to obtain robust estimates. Therefore, parameters from PV markets of other countries and parameters from the solar water heaters (SWH) market in Brazil are used in the analysis. The latter approach is carefully justified. A comparative analysis of distributed PV and SWH market features indicates that SWH diffusion parameters lead to a better representation of innovators behavior for residential PV adoption in Brazil than the parameters borrowed from other countries, which are used by the official projections performed by the Brazilian regulator of the electricity sector. Moreover, we propose a different approach for estimating the final potential market. We discuss the limitations of the official projections, since results indicate that official projections overestimated the diffusion of residential PV market in the early years. Finally, it is suggested that inaccurate signals could be given to stakeholders.

An online testing design choice typology towards cheating threat minimisation

Online testing is a popular practice for tertiary educators, largely owing to efficiency in automation, scalability, and capability to add depth and breadth to subject offerings. As with all assessments, designs need to consider whether student cheating may be inadvertently made easier and more difficult to detect. Cheating can jeopardise the validity of inference drawn from the measurements produced by online tests, leading to inaccurate signals and misperceptions about what students know and can do. This paper extends theoretical understanding about cheating behaviours to link online test design choices and their influence on a student’s capability and willingness to cheat. This research reviews the literature on cheating theories and a typology construction methodology to relate common online test design choices to their cheating threat consequence. In doing so, the typology offers educators designing online tests general normative guidance aimed at reducing threats to assessment inference validity, and academic integrity in general, brought about by student cheating. While we admit that cheating cannot be completely eliminated in online testing, the guidance provided by the typology can assist educators to structure online tests to minimise cheating.

A Fault-Signal-Based Generalizing Remaining Useful Life Prognostics Method for Wheel Hub Bearings

The goal of this work is to improve the generalization of remaining useful life (RUL) prognostics for wheel hub bearings. The traditional life prognostics methods assume that the data used in RUL prognostics is composed of one specific fatigue damage type, the data used in RUL prognostics is accurate, and the RUL prognostics are conducted in the short term. Due to which, a generalizing RUL prognostics method is designed based on fault signal data. Firstly, the fault signal model is designed with the signal in a complex and mutative environment. Then, the generalizing RUL prognostics method is designed based on the fault signal model. Lastly, the simplified solution of the generalizing RUL prognostics method is deduced. The experimental results show that the proposed method gained good accuracies for RUL prognostics for all the amplitude, energy, and kurtosis features with fatigue damage types. The proposed method can process inaccurate fault signals with different kinds of noise in the actual working environment, and it can be conducted in the long term. Therefore, the RUL prognostics method has a good generalization.

Multiple Fusion Based on the CCD and MEMS Accelerometer for the Low-Cost Multi-Loop Optoelectronic System Control.

In the charge-coupled device (CCD) and micro-electro-mechanical system (MEMS) accelerometer based low-cost multi-loop optoelectronic control system (OCS), due to accelerometers’ drift and noise in low frequency, the disturbance suppression (DS) is insufficient. Previously, based on the acceleration and position dual-loop control (ADLC), researchers combined a disturbance observer (DOB) with a virtual velocity loop to make some medium-frequency DS exchange for low-frequency performance. However, it is not optimal because the classic DOB based on accelerometers’ inaccurate signals cannot observe accurate disturbance in low frequency and the velocity based on a CCD and accelerometer time-domain fusion carried the CCD’s delay, resulting in the drop of medium-frequency DS. In this paper, considering the CCD’s advantage in low frequency and the accelerometer’s strength in high frequency, we propose to fuse their signals twice with a modified complementary filter method to respectively acquire an acceleration and velocity. The new acceleration with no drift and less noise but lower bandwidth creates a new acceleration model and is only used in fusion DOB (FDOB), while the velocity with little delay is to build an additional velocity loop. Compared with the traditional DOB enhanced by the time-domain fusion velocity loop, experiments verify that the proposed multiple fusion would apparently enhance the system’s DS, especially in low and medium frequency.

What Patients with Mild-to-Moderate Kidney Disease Know, Think, and Feel about Their Disease: An In-Depth Interview Study.

It is unknown what patients in primary care with mild-to-moderate chronic kidney disease (CKD) know, think, and feel about their diagnoses and how they value the information provided. The aim of the study was to explore their knowledge, thoughts, and experiences concerning their CKD and the information given to them. Qualitative interview study with patients with mild-to-moderate CKD who know their diagnoses and are treated mainly by family physicians. Four themes arose: CKD literacy, coping with anxiety, prerequisites for self-management, and reciprocity in information provision. The participants filled deficiencies in their CKD knowledge with misconceptions and half-truth about causes, symptoms, and treatment. The anxiety about CKD at the time of diagnosis versus the feeling of irrelevance later on was due to the absence of CKD symptoms and their physicians' minimization of the seriousness of CKD. Participants failed to connect lifestyle and cardiovascular disease with CKD. Not all participants were well informed about the consequences that CKD might have. CKD literacy and willingness to change were both necessary to accept lifestyle changes. Further, the participants felt that it would be helpful when information comes with empathy and is tailored to patients' personal needs. Patients have various perceptions about their CKD. Exploring these perceptions could help match their needs with better-tailored information. Doctors should be aware that they can deliver inaccurate signals about CKD severity, so that patients fail to realize the potential impact of CKD. This makes them less open to lifestyle changes and improving their self-management.

Flow-induced signal misallocation artifacts in two-point fat-water chemical shift MRI.

Two-point fat-water separation methods are increasingly being used for chest and abdominal MRI and have recently been introduced for use in MR angiography of the lower extremities. With these methods, flowing spins can accumulate unintended phase shifts between the echo times. The purpose of this study is to demonstrate that these phase shifts can lead to inaccurate signals in the water and fat images. In vitro experiments were conducted at 1.5T and 3.0T using a stenosis-mimicking phantom and a computer-controlled pump to image a range of physiologically relevant velocities. In the phantom images acquired using bipolar readout gradients, fat-water signal inaccuracies were visible in regions of flow, with increasing severity as the flow rate was increased. Additionally, similar effects were observed in regions of high flow in clinical chest and liver exams. In the phantom images, the effect was eliminated by using a dual-pass method without bipolar readout gradients. When using fat-water separation methods with bipolar readout gradients, phase shifts caused by the motion of spins can lead to signal inaccuracies in the fat and water images. These artifacts can be mitigated by using approaches that do not use bipolar readout gradients.

A Bridge Too Far? Challenges in Evaluating Principal Effectiveness

Purpose: The purpose of this article is to examine the assumptions underlying efforts to evaluate principal effectiveness in terms of student test scores, to review extant research on efforts to estimate principal effectiveness, and to discuss the appropriateness of including estimates of principal effectiveness in evaluations of principals. Method: We review 10 different strategies for estimating principal effectiveness based on student test scores, representing all of the strategies currently employed by states and districts. We base our reviews on the literature in three areas: use of test scores, evaluation, and statistical approaches to estimating the effects of individuals and schools on student test scores. Conclusions: We conclude there are currently no strategies to estimate principal effectiveness that accurately capture the independent effect of principals on student test scores; thus, these current strategies send inaccurate signals to both principals and those who make employment decisions about principals. Moreover, we also conclude a substantial proportion of principals could not be included in the most accurate strategies to assess principal effectiveness. Implications: This research has profound implications for states and districts implementing principal evaluation systems, particularly those making high-stakes decisions about principals based on statistical estimates of principal effectiveness. Indeed, such statistical estimates should be used not for making judgments or decisions about principals but rather as a screening tool to identify where states and districts should focus more in-depth and accurate strategies to evaluate principal effectiveness.

THE QUALITY OF INFORMATION AND INCENTIVES FOR EFFORT*

We study the relationship between the precision of information about the performance of an agent in a market, and the incentives this agent has for exerting effort to produce high quality. We show that this relationship can be nonmonotonic. There exists an efficient plausible equilibrium that induces a threshold beyond which any further improvement in the precision of information weakens the agent's incentive to produce high quality. Accordingly, both very accurate and very inaccurate signals about the agent's performance may destroy its incentive to exert effort. A few applications of this result are discussed.

Resource value and the context dependence of receiver behaviour

Many animals use signals of fighting ability to minimize the costs of competition. Theory predicts that signals must be costly to remain reliable indicators of their bearer's abilities, but many signals of fighting ability lack obvious developmental costs. Instead, receivers are thought to maintain signal accuracy by behaving aggressively towards individuals with inaccurate signals (i.e. social costs). Models predict that the evolutionary stability of social cost signals depends on receivers trusting signals in certain contexts and testing signal accuracy in other contexts. Here, I use the signals of agonistic ability in Polistes dominulus wasps to provide the first experimental evidence that receiver responses to social cost signals are context dependent. During contests over low-value resources, wasps trust signals; they avoid patches of food guarded by rivals with elaborate signals. As the value of the resource increases, wasps become more likely to test signal accuracy. In fact, receivers challenge guards regardless of their signal phenotype when the resource is sufficiently valuable. Context-dependent receiver responses are likely to be an important behavioural mechanism underlying the evolution of social costs, as context-dependent responses allow receivers to minimize the costs of conflict while also ensuring signal accuracy.

Effect of normalisation on detection of differentially expressed genes in cDNA microarray data analysis

Four different normalisation techniques were applied for the corrections of fluorescence data generated by a cDNA microarray experiment. Correction for inaccurate signals and possible bias induced by fluorescence intensity, background intensity and dye effect were used in different combinations. Results of the present study highlight a pronounced role for the normalisation techniques in the absolute number of genes different expressed and a low concordance between different methods. Moreover, a significant effect of the dependent variable used, mean or median fluorescence intensity, was observed.

Detecting false expression signals in high-density oligonucleotide arrays by an in silico approach

High-density oligonucleotide arrays have become a popular assay for concurrent measurement of mRNA expression at the genome scale. Much effort has been devoted to the development of statistical analysis tools aimed at reducing experimental noise and normalizing experimental variation in gene expression analysis. However, these investigations do not detect or catalog systematic problems associated with specific oligonucleotide probes. Here, we present an investigation of problematic probes that yield consistent but inaccurate signals across multiple experiments. By evaluating data integrity among gene, probe sequence, and genomic structure we identified a total of 20,696 (10.5%) nonspecific probes that could cross-hybridize to multiple genes and a total of 18,363 (9.3%) probes that miss the target transcript sequences on the Affymetrix GeneChip U95A/Av2 array. The numbers of nonspecific and mistargeted probes on the U133A array are 29,405 (12.1%) and 19,717 (8.0%), respectively. The poor performance of the mistargeted probes was confirmed in two GeneChip experiments, in which these probes showed a 20–30% decrease in detecting present signals compared with normal probes. Comparison of qualitative expression signals obtained from SAGE and EST data with those from GeneChip arrays showed that the consistency of the two platforms is 30% lower in problematic probes than in normal probes. A Web application was developed to apply our results for improving the accuracy of expression analysis.

Tropic failure of Phyllactinia corylea contributes to the mildew resistance of mulberry genotypes.

Different mulberry genotypes show great variation in their resistance to the powdery mildew Phyllactinia corylea. Conidial germination and hyphal growth of P. corylea on the leaf surface of two susceptible mulberry genotypes, viz., Kanva 2 (K2) and Victory 1 (V1) varieties of Morus indica, and on two resistant species, viz,, M. laevigata and M. serrata were studied by scanning electron microscopy. Conidial germination and growth of germ tubes were normal on all the leaves. The hyphae of P. corylea identify stomata on host leaves by their topographical features to produce the stomatopodia precisely over them. The holes and/or the grooves of stomata appear to provide the signals for the initiation of stomatopodia and similar structures are erratically developed over many local depressions or grooves on leaf surface. The abaxial surface of K2 leaf is smooth without prominent undulations of epidermal cell surface, and the stomata are flush with the leaf surface. Although successful penetration is also achieved on V1 leaf, its slightly undulated surface occasionally provides inaccurate tropic signals to the hyphae, inducing the development of stomatopodia away from the stomata. The leaf surfaces of M. laevigata and M. serrata are very rough with highly sculptured cuticle and abundant epidermal outgrowths. Stomata mostly remain sunken or hidden amidst the cuticular ornamentations and the hyphae fail to recognise the precise signals from them. As the surface architecture of the leaves provides many immense sources of tropic signals, stomatopodia are often produced over local depressions or grooves. In these cases the fungus fails to penetrate the leaf, does not develop beyond 24 h and penetration is rarely achieved on the leaves of the resistant plants. The study indicates that the stimulatory effect of the leaf surface topography of resistant varieties misleads the pathogen from successful penetration, thus contributing to the plant's resistance.

Microarray optimizations: increasing spot accuracy and automated identification of true microarray signals.

In this paper, fluorescent microarray images and various analysis techniques are described to improve the microarray data acquisition processes. Signal intensities produced by rarely expressed genes are initially correctly detected, but they are often lost in corrections for background, log or ratio. Our analyses indicate that a simple correlation between the mean and median signal intensities may be the best way to eliminate inaccurate microarray signals. Unlike traditional quality control methods, the low intensity signals are retained and inaccurate signals are eliminated in this mean and median correlation. With larger amounts of microarray data being generated, it becomes increasingly more difficult to analyze data on a visual basis. Our method allows for the automatic quantitative determination of accurate and reliable signals, which can then be used for normalization. We found that a mean to median correlation of 85% or higher not only retains more data than current methods, but the retained data is more accurate than traditional thresholds or common spot flagging algorithms. We have also found that by using pin microtapping and microvibrations, we can control spot quality independent from initial PCR volume.

Conservation rates in the real world

Conservation‐oriented rates that reflect the true price of water can change consumers' water use and pay off in reduced operating and development costs.Old and familiar ways of setting water rates can fail to recover the cost of providing water service, can send inaccurate signals as to the worth of this scarce resource, and are becoming more and more difficult to defend. At the same time, revenues from rates and charges are essential if water agencies are to accomplish their mission of providing dependable, potable water on demand. What can water utilities do to price water more sensibly, ensure financial viability, and achieve a publicly accepted and successful rate‐making process? The California Urban Water Conservation Council has developed a technical handbook on alternative pricing approaches and their associated effects. “Designing, Evaluating, and Implementing Conservation Rate Structures”1 demonstrates how quantitative tools can be used to measure rate effects, develop strategies for managing the results of rate changes, and provide insights about the process of successful rate‐making. By linking technical knowledge with practical implementation tools, rate‐making that incorporates conservation objectives can be accomplished.

Saccades to somatosensory targets. II. motor convergence in primate superior colliculus.

1. We examined cells with saccade-related activity in the superior colliculus (SC) of monkeys performing saccades to both somatosensory and visual targets. Our goals were 1) to determine whether signals from these separate sensory systems have converged onto a common motor pathway by the level of the SC; 2) to determine the frame of reference of somatosensory saccade signals in the SC; and 3) to relate collicular motor activity to the behavioral characteristics of somatosensory saccades. 2. Somatosensory targets consisted of vibrotactile stimuli delivered to the hands, which were held in fixed spatial positions. Saccades of different directions and amplitudes were elicited from different initial eye positions. Of 86 cells with motor-related activity, 85 (99%) discharged for saccades to both visual and somatosensory targets. The remaining cell was active only for visual saccades. 3. Cells with saccade-related activity had movement fields representing the direction and amplitude of saccades to both visual and somatosensory targets. We found no cells that discharged for saccades to a particular somatosensory target regardless of the vector of the saccade. 4. Small modality-dependent differences in the spatial tuning of the movement fields were observed, but these variations formed no clear pattern. Given the large population of cells active in conjunction with each saccade, these small tuning differences may have no net effect. Because the visual and somatosensory movement fields of individual cells were similar to each other, the inaccuracy of somatosensory saccades is likely to be the result of inaccurate signals reaching the SC, rather than an error signal added downstream. 5. The peak discharge frequency of collicular motor cells was lower for somatosensory saccades than for visual saccades, although the number of spikes in the discharge was about the same. 6. The latency of the onset of the prelude of motor activity following the cue to initiate a saccade was about the same for somatosensory and visual trials, even though somatosensory saccades have longer reaction times than visual saccades. However, the peak of the motor activity was delayed on somatosensory trials such that the timing of the peak was the same with respect to the movement on somatosensory and visual trials. 7. We conclude that the same population of saccade-related neurons in the SC that represents saccades to visual targets also represents saccades to somatosensory targets. Somatosensory saccades are encoded by these cells as the change in eye position necessary to bring the target onto the fovea, rather than the location of the stimulus on the body surface. Modality-dependent differences in the frequency and timing of collicular motor activity may contribute to velocity and reaction time differences.