Oblique Pyramid Microstructure-Patterned Flexible Sensors for Pressure and Visual Temperature Sensing

Flexible tactile sensors have garnered considerable attention in diverse fields. Among them, the sensors integrated with multifunctional tactile sensing features can simultaneously detect various stimuli, such as pressure and temperature, and are thus suitable for practical applications. However, integrating multiple sensor modalities within a solitary pixel invariably encounters various limitations encompassing interplay among disparate sensors, intricate structural design demands, and the complexities and high costs associated with fabrication. Herein, we harness a visual sensing mechanism to synergize with electric sensors, thereby realizing a tactile sensor reliant on thermochromic microstructures for simultaneous pressure and temperature sensing. The thermal distribution could be easily displayed by the color change of the sensor, avoiding inference between the sensing units, which is beneficial for low-cost mass fabrication. A capacitor sensor with dual-scale oblique pyramid microstructures in its dielectric layer is used for the pressure sensing function, resulting in improved sensitivity and an extended measurement range. This innovative tactile sensor design offers insights into tactile sensing mechanisms, paving the way for cost-effective, high-performance, and multimodal sensor fabrication

Real-Time, Selective Detection of Copper(II) Using Ionophore-Grafted Carbon-Fiber Microelectrodes

Rapid, selective detection of metals in complex samples remains an elusive goal that could provide critical analytical information for biological and environmental sciences and industrial waste management. Fast-scan cyclic voltammetry (FSCV) using carbon-fiber microelectrodes (CFMs) is an emerging technique for metal analysis with broad potential applicability because of its rapid response to changes in analyte concentration and minimal disturbance to the analysis medium. In this communication, we report the first effective application of covalently modified CFMs to achieve highly selective, subsecond Cu­(II) measurements using FSCV. A two-part strategy is employed for maximum selectivity: Cu­(II) binding is augmented by a covalently grafted ionophore, while binding of other metals is prevented by chemical blocking of nonselective surface adsorption sites. The resulting electrodes selectively detect Cu­(II) in a complex medium comprising several interfering metals. Overall, this strategy represents a transformative innovation in real-time electrochemical detection of metal analytes

Fast-Scan Deposition-Stripping Voltammetry at Carbon-Fiber Microelectrodes: Real-Time, Subsecond, Mercury Free Measurements of Copper

Elevated concentrations of hazardous metals in aquatic systems are known to threaten human health. Mobility, bioavailability, and toxicity of metals are controlled by chemical speciation, a dynamic process. Understanding metal behavior is limited by the lack of analytical methods that can provide rapid, sensitive, in situ measurements. While electrochemistry shows promise, it is limited by its temporal resolution and the necessity for Hg modified electrodes. In this letter, we apply fast-scan deposition-stripping voltammetry at carbon-fiber microelectrodes for in situ measurements of Cu­(II). We present a novel, Hg-free technique that can measure Cu­(II) with ppb sensitivity at 100 ms temporal resolution

Governance Policy Evaluation in the United States during the Pandemic: Nonpharmaceutical Interventions or Else?

Scientific evidence suggests that nonpharmaceutical interventions (NPIs) effectively curb the spread of COVID-19 before a pharmaceutical solution. Implementing these interventions also significantly affects regular socioeconomic activities and practices of social, racial, and political justice. Local governments often face conflicting goals during policymaking. Striking a balance among competing goals during a global pandemic is a fine science of governance. How well state governments consume the scientific evidence and maintain such a balance remains less understood. This study employs a set of Bayesian hierarchical models to evaluate how state governments in the United States use scientific evidence to balance the fighting against the spread of COVID-19 disease and socioeconomic, racial, social justice, and other demands. We modeled the relationships between five NPI strategies and COVID-19 caseload information and used the modeled result to perform a balanced governance evaluation. The results suggest that governmental attitude and guidance effectively guide the public to fight back against a global pandemic. The more detailed spatiotemporally varying coefficient process model produces 612,000 spatiotemporally varying coefficients, suggesting all measures sometimes work somewhere. Summarized results indicate that states emphasizing NPIs fared well in curbing the spread of COVID-19. With over 1 million deaths due to COVID-19 in the United States, we feel the balance scale likely needs to tip toward preserving human lives. Our evaluation of governance policies is hence based on such an argument. This study aims to provide decision support for policymaking during a national emergency.</p

Real-Time Subsecond Voltammetric Analysis of Pb in Aqueous Environmental Samples

Lead (Pb) pollution is an important environmental and public health concern. Rapid Pb transport during stormwater runoff significantly impairs surface water quality. The ability to characterize and model Pb transport during these events is critical to mitigating its impact on the environment. However, Pb analysis is limited by the lack of analytical methods that can afford rapid, sensitive measurements <i>in situ</i>. While electrochemical methods have previously shown promise for rapid Pb analysis, they are currently limited in two ways. First, because of Pb’s limited solubility, test solutions that are representative of environmental systems are not typically employed in laboratory characterizations. Second, concerns about traditional Hg electrode toxicity, stability, and low temporal resolution have dampened opportunities for <i>in situ</i> analyses with traditional electrochemical methods. In this paper, we describe two novel methodological advances that bypass these limitations. Using geochemical models, we first create an environmentally relevant test solution that can be used for electrochemical method development and characterization. Second, we develop a fast-scan cyclic voltammetry (FSCV) method for Pb detection on Hg-free carbon fiber microelectrodes. We assess the method’s sensitivity and stability, taking into account Pb speciation, and utilize it to characterize rapid Pb fluctuations in real environmental samples. We thus present a novel real-time electrochemical tool for Pb analysis in both model and authentic environmental solutions

AMOVA of the 197 sweet potato accessions collected in this study.

<p>AMOVA of the 197 sweet potato accessions collected in this study.</p

Comparison between the model-based groups.

<p>Comparison between the model-based groups.</p

Regional distribution of the total collection and the core set in this study.

<p>Regional distribution of the total collection and the core set in this study.</p

AMOVA of the sweet potato core set.

<p>AMOVA of the sweet potato core set.</p

Comparison of the frequency of occurrence of alleles in the total collection <i>versus</i> the core set.

<p>The x-axis indicated ten allele types, (1) AA; (2) CC; (3) GG; (4) TT; (5) GT/TG; (6) AC/CA; (7) AG/GA; (8) CG/GC; (9) AT/TA; (10) CT/TC. The y-axis showed the allele frequencies.</p