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Innovation (Cambridge (Mass.)) Jul 2024Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy... (Review)
Review
Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health. Despite global efforts to mitigate legacy pollutants, the continuous introduction of new substances remains a major threat to both people and the planet. In response, global initiatives are focusing on risk assessment and regulation of emerging contaminants, as demonstrated by the ongoing efforts to establish the UN's Intergovernmental Science-Policy Panel on Chemicals, Waste, and Pollution Prevention. This review identifies the sources and impacts of emerging contaminants on planetary health, emphasizing the importance of adopting a One Health approach. Strategies for monitoring and addressing these pollutants are discussed, underscoring the need for robust and socially equitable environmental policies at both regional and international levels. Urgent actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.
PubMed: 38756954
DOI: 10.1016/j.xinn.2024.100612 -
Physical Review. E Apr 2024We present a simple model to predict network activity at the edge level by extending a known approximation method to compute betweenness centrality with a repulsive...
We present a simple model to predict network activity at the edge level by extending a known approximation method to compute betweenness centrality with a repulsive mechanism to prevent unphysical densities. By taking into account the strong interaction effects often observed in real phenomena, we aim to obtain an improved measure of edge usage during rush hours as traffic congestion patterns emerge in urban networks. In this approach, the network is iteratively populated by agents following dynamically evolving fastest paths who are progressively attracted towards uncongested parts of the network as the global traffic volume increases. Following the transition of the network state from empty to saturated, we study the emergence of congestion and the progressive disruption of global connectivity due to a relatively small fraction of crowded edges. We assess the predictive power of our model by comparing the speed distribution against a large experimental data set for the London area with remarkable results, which also translate into a qualitative similarity of the congestion maps. Also, percolation analysis confirms the quantitative agreement of the model with the real data for London. We perform simulations for seven other topologically different cities to obtain the Fisher critical exponent τ that shows no common functional dependence on the traffic level. The critical exponent γ, studied to assess the power-law decay of spatial correlation, is found to be inversely proportional to the number of vehicles for both real and simulated traffic. This simulation approach seems particularly fit to describe qualitative and quantitative properties of the network loading process, culminating in peak-hour congestion, by using only topological and geographical network features.
PubMed: 38755873
DOI: 10.1103/PhysRevE.109.044302 -
Science (New York, N.Y.) May 2024Hexavalent iridium (Ir) oxide is predicted to be more active and stable than any other iridium oxide for the oxygen evolution reaction in acid; however, its experimental...
Hexavalent iridium (Ir) oxide is predicted to be more active and stable than any other iridium oxide for the oxygen evolution reaction in acid; however, its experimental realization remains challenging. In this work, we report the synthesis, characterization, and application of atomically dispersed Ir oxide (Ir-) for proton exchange membrane (PEM) water electrolysis. The Ir- was synthesized by oxidatively substituting the ligands of potassium hexachloroiridate(IV) (KIrCl) with manganese oxide (MnO). The mass-specific activity (1.7 × 10 amperes per gram of iridium) and turnover number (1.5 × 10) exceeded those of benchmark iridium oxides, and in situ x-ray analysis during PEM operations manifested the durability of Ir at current densities up to 2.3 amperes per square centimeter. The high activity and stability of Ir- showcase its promise as an anode material for PEM electrolysis.
PubMed: 38723092
DOI: 10.1126/science.adg5193 -
Journal of Colloid and Interface Science Sep 2024Producing hydrogen through electrocatalytic overall water splitting with ampere-level current density is still limited by the high cost and poor stability of...
Producing hydrogen through electrocatalytic overall water splitting with ampere-level current density is still limited by the high cost and poor stability of electrocatalysts. In this work, a new type NiP/MnP heterojunction composite material was designed and prepared as bifunctional electrocatalyst. Based on XPS spectra and theoretical calculation, the formation of NiP/MnP heterojunction successfully modulates the local electronic structure of NiP and enhances the ionization of H and Ni by increasing the electron transfer rate. Moreover, the special nanovilli structure and superhydropholic/superaerophobic surface of NiP/MnP heterojunction accelerates the transfer of electrolyte and gaseous products. Benefiting from these advantages, the as-prepared NiP/MnP/CF not only exhibits superior electrocatalytic performance, which can release 10 mA/cm current density with a low overpotential of 69 mV and 247 mV for HER and OER respectively, but also shows admirable stability of continuous overall water splitting to drive 1000 mA/cm for 180 h without notable activity degradation. We believe this material possesses outstanding potential for industrial applications, and our strategy may provide a new pathway to design relative materials.
PubMed: 38718588
DOI: 10.1016/j.jcis.2024.05.002 -
The Review of Scientific Instruments Apr 2024In recent years, linearization technology for nonlinear devices has become a hot topic in many fields. In this study, a linear voltage divider based on metal oxide...
In recent years, linearization technology for nonlinear devices has become a hot topic in many fields. In this study, a linear voltage divider based on metal oxide arresters was designed by combining linearization technology and electrical measurement technology to solve the objective problems of online voltage monitoring. These problems include high difficulty in equipment installation, low measurement accuracy, and poor economic benefits. Based on a summary of linearization theory, the sufficient and necessary conditions for the linearization of the voltage divider were deduced in detail. The relevant circuit simulations were conducted, along with voltage divider experiments under power frequency AC voltage, operating overvoltage, and lightning overvoltage. The results revealed that the voltage divider was able to realize linearized measurements and meet the relevant standards of online voltage monitoring. The measurement errors were concentrated in the transition region between the pre-breakdown region (small current region) and the breakdown region (nonlinear region) in the volt-ampere characteristic curve. The main influencing factor of errors was the consistency of the nonlinear characteristics of the high- and low-voltage arms of the voltage divider. The voltage divider designed in this study can be applied in many scenarios, such as power plants, substations, high-voltage electrical equipment manufacturing plants, and high-voltage laboratories.
PubMed: 38683056
DOI: 10.1063/5.0203065 -
Bioengineering (Basel, Switzerland) Apr 2024Accurate measurements of limb volumes are important for clinical reasons. We aimed to assess the reliability and validity of two centimetric and two optoelectronic...
BACKGROUND
Accurate measurements of limb volumes are important for clinical reasons. We aimed to assess the reliability and validity of two centimetric and two optoelectronic techniques for limb volume measurements against water volumetry, defined as the gold standard.
METHODS
Five different measurement methods were executed on the same day for each participant, namely water displacement, fixed-height (circumferences measured every 5 (10) cm for the upper (lower limb) centimetric technique, segmental centimetric technique (circumferences measured according to proportional height), optoelectronic plethysmography (OEP, based on a motion analysis system), and IGOODI Gate body scanner technology (which creates an accurate 3D avatar).
RESULTS
A population of 22 (15 lower limbs, 11 upper limbs, 8 unilateral upper limb lymphoedema, and 6 unilateral lower limb lymphoedema) participants was selected. Compared to water displacement, the fixed-height centimetric method, the segmental centimetric method, the OEP, and the IGOODI technique resulted in mean errors of 1.2, 0.86, -16.0, and 0.71%, respectively. The corresponding slopes (and regression coefficients) of the linear regression lines were 1.0002 (0.98), 1.0047 (0.99), 0.874 (0.94) and 0.9966 (0.99).
CONCLUSION
The centimetric methods and the IGOODI system are accurate in measuring limb volume with an error of <2%. It is important to evaluate new objective and reliable techniques to improve diagnostic and follow-up possibilities.
PubMed: 38671803
DOI: 10.3390/bioengineering11040382 -
Analytical Sciences : the International... Apr 2024Designing portable electrochemical sensors combined with highly efficient glucose oxidation electrodes offers a significant opportunity for convenient glucose detection....
Designing portable electrochemical sensors combined with highly efficient glucose oxidation electrodes offers a significant opportunity for convenient glucose detection. In this report, we present the design and preparation of platinum deposited Ni/NiFeO/Carbon composite (Pt/Ni/NiFeO/C) derived from Ni/Fe metal-organic frameworks (MOFs) followed by Pt deposition. Energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electron microscopy (EM) were utilized to analyze the crystal structure, morphology, and chemical composition of the resulting materials. The glucose sensing capabilities of the optimal Pt/Ni/NiFeO/C-3 were assessed using amperometry methods on a smartphone-based portable device. Acting as a nonenzymatic glucose sensor, the Pt/Ni/NiFeO/C-3 electrode demonstrated notable sensitivity and a low limit of detection for glucose. The portable sensor exhibits high sensitivities of 131.88 μM mM cm at low glucose concentration (3-500 μM) and 29.52 μA mM cm at high glucose concentration (700-4000 μM), achieving a low detection limit of 1.1 μM (S/N = 3). The sensor also demonstrates enhanced selectivity and stability for detecting glucose. Furthermore, the portable sensor exhibits a clear step-ampere response in the detection of serum samples with satisfactory recovery ranging from 99.30 to 101.32%. This suggests the significant potential of portable glucose sensing applications.
PubMed: 38671292
DOI: 10.1007/s44211-024-00578-8 -
Entropy (Basel, Switzerland) Apr 2024Multimodal datasets are ubiquitous in modern applications, and multimodal Variational Autoencoders are a popular family of models that aim to learn a joint...
Multimodal datasets are ubiquitous in modern applications, and multimodal Variational Autoencoders are a popular family of models that aim to learn a joint representation of different modalities. However, existing approaches suffer from a coherence-quality tradeoff in which models with good generation quality lack generative coherence across modalities and vice versa. In this paper, we discuss the limitations underlying the unsatisfactory performance of existing methods in order to motivate the need for a different approach. We propose a novel method that uses a set of independently trained and unimodal deterministic autoencoders. Individual latent variables are concatenated into a common latent space, which is then fed to a masked diffusion model to enable generative modeling. We introduce a new multi-time training method to learn the conditional score network for multimodal diffusion. Our methodology substantially outperforms competitors in both generation quality and coherence, as shown through an extensive experimental campaign.
PubMed: 38667874
DOI: 10.3390/e26040320 -
Angewandte Chemie (International Ed. in... Jul 2024Electrocatalytic reduction of nitrate to ammonia provides a green alternate to the Haber-Bosch method, yet it suffers from sluggish kinetics and a low yield rate. The...
Electrocatalytic reduction of nitrate to ammonia provides a green alternate to the Haber-Bosch method, yet it suffers from sluggish kinetics and a low yield rate. The nitrate reduction follows a tandem reaction of nitrate reduction to nitrite and subsequent nitrite hydrogenation to generate ammonia, and the ammonia Faraday efficiency (FE) is limited by the competitive hydrogen evolution reaction. Herein, we design a heterostructure catalyst to remedy the above issues, which consists of Ni nanosphere core and Ni(OH) nanosheet shell (Ni/Ni(OH)). In situ Raman spectroscopy reveals Ni and Ni(OH) are interconvertible according to the applied potential, facilitating the cascade nitrate reduction synergistically. Consequently, it attains superior electrocatalytic nitrate reduction performance with an ammonia FE of 98.50 % and a current density of 0.934 A cm at -0.476 V versus reversible hydrogen electrode, and exhibits an average ammonia yield rate of 84.74 mg h cm during the 102-hour stability test, which is highly superior to the reported catalysts tested under similar conditions. Density functional theory calculations corroborate the synergistic effect of Ni and Ni(OH) in the tandem reaction of nitrate reduction. Moreover, the Ni/Ni(OH) catalyst also possesses good capability for methanol oxidation and thus is used to establish a system coupling with nitrate reduction.
PubMed: 38651747
DOI: 10.1002/anie.202406750 -
Sensors (Basel, Switzerland) Mar 2024Currently, cutting-edge, high-frequency current sources are limited by switching devices and wire materials, and the output current cannot take into account the demands...
Currently, cutting-edge, high-frequency current sources are limited by switching devices and wire materials, and the output current cannot take into account the demands of a high peak and low rise time at the same time. Based on the output demand of a current source, a non-inductive coil for providing high-frequency, high current sources with low rise times is designed. The coil is appropriately designed according to the principle of the ampere-turn method, where several turns of wire are utilized to linearly synthesize the current to obtain high-frequency currents with amplitudes up to 30 kA. However, the inductance formed after winding the coil could possess a hindering effect on the high-frequency current. In the present investigation, based on the law of energy conservation and utilizing the principle of transformer coupling, the inductor's hindering effect on high-frequency currents is appropriately eliminated by consuming the stored energy of the inductor innovatively. Theoretical calculations and practical tests show that the inductance of a two-layer 28-turn coil is 42 times smaller than that of a two-layer, 28-turn perfect circular spiral PCB coil. The measured inductance is only 6.69 μH, the output current amplitude is calculated to be up to 33 kA with a rise time of 20 ns, and the output waveform corresponding to a 1 MHz square wave is not remarkably distorted. This effective design idea could be very helpful in solving the problem of high peak values and low rise times in high-frequency, high-current source output design.
PubMed: 38610240
DOI: 10.3390/s24072027