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Data standardization combined with descriptive metadata facilitate data reuse, which is the ultimate goal of the Findable, Accessible, Interoperable, and Reusable (FAIR) principles. Community data or metadata standards are increasingly created through an approach that emphasizes collaboration between various stakeholders. Such an approach requires platforms for collaboration on the development process that centers on sharing information and receiving feedback. Our objective in this study was to conduct a systematic review to identify data standards and reporting formats that use version control for developing data standards and to summarize common practices, particularly in earth and environmental sciences. Out of 108 data standards and reporting formats identified in our review, 32 used GitHub as the version control platform, and no other platforms were used. We found no universally accepted methodology for developing and publishing data standards. Many GitHub repositories did not use key features that could help developers to gather user feedback, or to create and revise standards that build on previous work. We provide guidance for community-driven standard development and associated documentation on GitHub based on a systematic review of existing practices.

Field observations of the soil-to-atmosphere CO2 flux—soil respiration, RS—are a prime example of ‘long tail’ data that historically have had neither centralized databases nor an agreed-upon reporting format. This has hindered scientific transparency, analytical reproducibility, and syntheses with respect to this globally-important component of the carbon cycle. Here we propose a new data and metadata reporting format for RS data, based on engagement with a wide range of researchers in the earth and ecological sciences as well as expert advisory panels. Our goal was a reporting format that would be relevant and useful for synthesis activities, optimizing data discoverability and usability while not placing an undue burden on data contributors. We describe previous RS data collection efforts, lessons learned from related databases and data-oriented networks (e.g., FLUXNET) in earth and ecological sciences, and the process of community consultation. The proposed reporting format focuses on chamber-level data and metadata, specifying measurement conditions and, for a given measurement period defined by beginning and ending timestamps, a mean RS flux (or CO2 concentration) and associated ancillary measurements. With input from the research community, we have also developed research data and metadata templates to support data collection adhering to the reporting format. Fundamentally, this format aims to enable findable, accessible, interoperable, and reusable data, while providing ‘future-proofing’ capabilities to support reanalyses using as yet unknown algorithms or approaches. This proposed RS reporting format is openly available online and is intended to be a dynamic document, subject to further community feedback and/or change.

Leaf-level gas exchange data support the mechanistic understanding of plant fluxes of carbon and water. These fluxes inform our understanding of ecosystem function, are an important constraint on parameterization of terrestrial biosphere models, are necessary to understand the response of plants to global environmental change, and are integral to efforts to improve crop production. Collection of these data using gas analyzers can be both technically challenging and time consuming, and individual studies generally focus on a small range of species, restricted time periods, or limited geographic regions. The high value of these data is exemplified by the many publications that reuse and synthesize gas exchange data, however the lack of metadata and data reporting conventions make full and efficient use of these data difficult. Here we propose a reporting format for leaf-level gas exchange data and metadata to provide guidance to data contributors on how to store data in repositories to maximize their discoverability, facilitate their efficient reuse, and add value to individual datasets. For data users, the reporting format will better allow data repositories to optimize data search and extraction, and more readily integrate similar data into harmonized synthesis products. The reporting format specifies data table variable naming and unit conventions, as well as metadata characterizing experimental conditions and protocols. For common data types that were the focus of this initial version of the reporting format, i.e., survey measurements, dark respiration, carbon dioxide and light response curves, and parameters derived from those measurements, we took a further step of defining required additional data and metadata that would maximize the potential reuse of those data types. To aid data contributors and the development of data ingest tools by data repositories we provided a translation table comparing the outputs of common gas exchange instruments. Extensive consultation with data collectors, data users, instrument manufacturers, and data scientists was undertaken in order to ensure that the reporting format met community needs. The reporting format presented here is intended to form a foundation for future development that will incorporate additional data types and variables as gas exchange systems and measurement approaches advance in the future. The reporting format is published in the U.S. Department of Energy's ESS-DIVE data repository, with documentation and future development efforts being maintained in a version control system.

This article is composed of three independent commentaries about the state of Integrated, Coordinated, Open, Networked (ICON) principles (Goldman, et al., 2021b, https://doi.org/10.1029/2021EO153180) in Earth and Space Science Informatics (ESSI) and includes discussion on the opportunities and challenges of adopting them. Each commentary focuses on a different topic: (Section 2) Global collaboration, cyberinfrastructure, and data sharing; (Section 3) Machine learning for multiscale modeling; (Section 4) Aerial and satellite remote sensing for advancing Earth system model development by integrating field and ancillary data. ESSI addresses data management practices, computation and analysis, and hardware and software infrastructure. Our role in ICON science therefore involves collaborative work to assess, design, implement, and promote practices and tools that enable effective data management, discovery, integration, and reuse for interdisciplinary work in Earth and space science disciplines. Networks of diverse people with expertise across Earth, space, and data science disciplines are essential for efficient and ethical exchanges of findable, accessible, interoperable, and reusable (FAIR) research products and practices. Our challenge is then to coordinate the development of standards, curation practices, and tools that enable integrating and reusing multiple data types, software, multi‐scale models, and machine learning approaches across disciplines in a way that is as open and/or FAIR as ethically possible. This is a major endeavor that could greatly increase the pace and potential of interdisciplinary scientific discovery. Plain Language Summary: We present commentaries on the state of "Integrated, Coordinated, Open, Networked (ICON) principles" in Earth and Space Science Informatics. ICON principles are meant to improve the research experience for all. Ultimately, data standardized according to community conventions and formats lead to more effective and efficient collaboration, data discovery, integration, and analyses. Data standards, tools, and machine learning developed using ICON principles enhance our understanding of Earth processes. Using ICON principles improves model results and efficacy, fosters interdisciplinary research, and provides a framework by which non‐experts can confidently contribute volunteered data and findings. Standardized data also provides reliable common resources to help train and benchmark machine learning algorithms. When networked communities work together to standardize and share data openly, the resulting web of research products is more readily findable, accessible, interoperable, and reusable. Ongoing support is crucial to develop and sustain the people, systems, and tools necessary to embrace ICON principles in Earth and Space Science Informatics now and in the future. Key Points: Networks across communities, with Coordinated data and information modeling practices, improve scientific outcomes for all involvedIntegrated, Coordinated, and Open data requires sustainable support to create and maintain infrastructure for interdisciplinary NetworksIntegrated and Coordinated use of data in machine learning calls for Open benchmark datasets shared across Networks for improved outcomes [ABSTRACT FROM AUTHOR]

The oxidation behaviour of Incoloy 909 superalloy subjected to diffusion boronizing treatments was studied at 750 and 850°C in atmospheres of dry air and a mixture of dry air + water vapour for times up to 10 h. The oxidation behaviour of the coated samples was described by the parabolic rate law with activation energies of 26 and 21 kJ mol−1 when oxidation was conducted in dry air or in the mixture dry air + water vapour respectively. Oxidation kinetics of the boronized coatings were sensitive to temperature and the oxidation environment promoting the development of a thick SiO2 layer on top of the coatings which also included minor additions of other oxides that acted as a barrier that reduced oxidation. However, in the conditions that included water vapour boron-rich oxides were also formed and a different oxidation behaviour was experienced. [ABSTRACT FROM AUTHOR]

An alternative solution to reduce environmental pollution using aluminum waste foundry sand (AWFS) and fly ash (FA) to produce sustainable construction materials was studied. New mortars were prepared by partially replacing ordinary Portland cement with fly ash at 5, 10 and 15 % mass. and a total replace of Ottawa sand (OS) with AWFS. The specimens were cured at 25°C with a 100% relative humidity. The mechanical behavior was evaluated by compression test at the ages of 7, 14 and 28 days. The microstructural characteristics were analyzed by scanning electron microscopy (SEM). The results indicate that the addition of milling fly ash in AWFS mortars increases the mechanical resistance, mostly at 5% mass reaching the maximum value of 10 MPa at 28 days of age. Microstructurally, it was found a porous cement matrix with some cracking caused by the reaction of portland cement with the metallic aluminum remaining in the waste sand, which is correlated to the low mechanical resistance obtained. The final mechanical characteristic makes this new product a serious candidate to be used as a sustainable building material working at low load. [ABSTRACT FROM AUTHOR]

The increasing energy demand and the limitations of the existing technologies due to the scarcity, cost and toxicity of the materials urge the researchers to hunt for efficient thin film solar cells based on earth-abundant, inexpensive and less toxic materials. For a decade, binary and ternary antimony based sulfides have gained attention due to their possible applications in solar cells. This interest is the basis of this review. In this review article, we describe basic properties of copper antimony sulfide (CuSbS) thin films to investigate their photovoltaic applications. A detailed description of the preparation methods, studies on morphologies and optoelectronic properties based on published work, including our experience are presented. A systematic review is done to demonstrate emerging interest in the photovoltaic performance of this compound. This review gives an in depth discussion on the structure, morphology, optical and electrical properties of copper antimony sulfide thin films. [ABSTRACT FROM AUTHOR]

In this study, it was evaluated the chemical interaction between iron ore (Fe2O3) and a refractory concrete based on Al2O3- MgAl2O4 at 1650 °C for 4 h using an air atmosphere, in order to determine the chemical behavior and possible reactions between these materials. After testing, the refractory concrete was microstructurally characterized by optical microscopy and scanning electron microscopy (SEM-EDS), as well as X-ray diffraction and Raman spectroscopy. The results showed that magnesium aluminate phase incorporates in solid solution Fe+2 ions, resulting in the formation of (Fe, Mg) (Al2O4) spinels and after their saturation, the rest of Fe+2 ions tends to precipitate at the grain boundaries of alumina and magnesium aluminate phases. This fact promotes during the concrete cooling, the formation of wustite, hematite and magnetite phases (detected in the microstructure as a dendritic and widmanstätten morphologies). The presence of hematite phase was corroborated by X-ray diffraction; likewise the presence of modified spinel phase whose hkl reflections width is higher compared with the original spinel, due to the incorporation of Fe+2 in the initial MgAl2O4 phase. For Raman spectroscopy, it was confirmed the presence of corundum (alumina) phase at characteristic frequencies of 378, 416 and 644 cm-1, hematite phase at 226, 292, 411 and 612 cm-1, magnetite phase at 520 and 668 cm-1 and spinel MgAl2O4 and (Fe, Mg) (Al2O4) ) with its main frequencies at 406 and 666 major cm-1. [ABSTRACT FROM AUTHOR]

IrO2/Pt catalysts (at different concentrations) were synthesized by incipient wetness technique and characterized by XRD, XRF, and SEM. Water electrolysis/fuel cell performances were evaluated in a 5 cm2 single cell under Unitized Regenerative Fuel Cell (URFC) configuration. The IrO2/Pt composition of 14/86 showed the highest performance for water electrolysis and the lowest one as fuel cell. It is derived that for fuel cell operation an excess of Pt favours the oxygen reduction process whereas IrO2 promotes oxygen evolution. From the present results, it appears that the diffusion characteristics and the reaction rate in fuel cell mode are significantly lower than in the electrolyser mode. This requires the enhancement of the gas diffusion properties of the electrodes and the catalytic properties for cathode operation in fuel cells. [ABSTRACT FROM AUTHOR]

IrO2–RuO2, IrO2–Pt and IrO2–Ta2O5 electrocatalysts were synthesized and characterized for the oxygen evolution in a Solid Polymer Electrolyte (SPE) electrolyzer. These mixtures were characterized by XRD and SEM. The anode catalyst powders were sprayed onto Nafion 117 membrane (catalyst coated membrane, CCM), using Pt catalyst at the cathode. The CCM procedure was extended to different in-house prepared catalyst formulations to evaluate if such a method could be applied to electrolyzers containing durable titanium backings. The catalyst loading at the anode was about 6 mg cm−2, whereas 1 mg cm−2 Pt was used at the cathode. The electrochemical activity for water electrolysis was investigated in a single cell SPE electrolyzer at 80 °C. It was found that the terminal voltage obtained with Ir–Ta oxide was slightly lower than that obtained with IrO2–Pt and IrO2–RuO2 at low current density (lower than 0.15 A cm−2). At higher current density, the IrO2–Pt and IrO2–RuO2 catalysts performed better than Ir–Ta oxide. [ABSTRACT FROM AUTHOR]

Pt and Pt-Fe catalysts supported on multiwalled carbon nanotubes (MWCNTs) were prepared by impregnation and reduction at intermediate temperature (400°C). The MWCNTs with diameters ranging from 20 to 100 nm were synthesized by a spray pyrolysis technique. Pt/MWCNTs and Pt-Fe/MWCNT catalysts were characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscope-energy dispersive X-ray analysis, and transmission electron microscopy techniques. The electro-catalytic behavior for the oxygen reduction reaction was investigated in rotating disk electrode configuration in an acidic medium, also in the presence of various methanol concentrations (0.01, 0.1, and 1 M). An anodic shift of the peak potential for methanol oxidation of ~150 mV was observed in the presence of 1 M methanol concentration for the Pt-Fe catalyst compared to the Pt catalyst. Both materials were used as cathodes in a direct methanol fuel cell at 30 and 60°C. A better performance was obtained for the cell based on Pt-Fe/MCWNTs as cathode catalyst. Although slight iron dissolution was observed after two weeks of discontinuous operation, the performance of the Pt-Fe catalyst was larger than the Pt catalyst. [ABSTRACT FROM AUTHOR]

A compact prototype system for H2 production based on a Polymer Electrolyte Membrane (PEM) stack was developed and investigated. A detailed study and an optimization of the Balance of Plant (BoP) was carried out. The system was developed in laboratory by using commercial devices tailored around in house-made membrane electrode assemblies (MEAs). The study regarded both the hydraulic circuit efficiency loss and its optimization by varying process parameters. Energy consumption for auxiliary devices was studied at different temperatures (40, 60 and 75 °C). Efficiency and control strategy management of the system were investigated. Despite an increase of stack performance observed at high temperature, maximum system efficiency (65% compared to HHV) was obtained at 40 °C because of moderate energy consumption by the electric heater. To evaluate the stack contribution to the overall efficiency, the present investigation was completed by a hydrodynamic study of the stack inside the system. Diffusional aspects related to the water mass distribution inside the stack were investigated through a computational fluid dynamic analysis (CFD). In particular, a 3D analysis of the whole stack composed by 120 channels and 10 cells was carried out. The model showed a quite uniform distribution of water over the individual channels and a homogeneous pressure inside the cells. Accordingly, the risk of having hot spots and gases accumulated inside the stack was minimal. [ABSTRACT FROM AUTHOR]

Abstract: World fossil fuel reserve is expected to be exhausted in coming few decades. Therefore, the decentralization of energy production requires the design and integration of different energy sources and conversion technologies to meet the power demand for single remote housing applications in a sustainable way under various weather conditions. This work focuses on the integration of photovoltaic (PV) system, micro-wind turbine (WT), Polymeric Exchange Membrane Fuel Cell (PEM-FC) stack and PEM water electrolyzer (PEM-WE), for a sustained power generation system (2.5 kW). The main contribution of this work is the hybridization of alternate energy sources with the hydrogen conversion systems using mid-term and short-term storage models based in artificial intelligence techniques built from experimental data (measurements obtained from the site of interest), this models allow to obtain better accuracy in performance prediction (PVMSE = 8.4%, PEM-FCMSE = 2.4%, PEM-WEMSE = 1.96%, GSRMSE = 7.9%, WTMSE = 14%) with a practical design and dynamic under intelligent control strategies to build an autonomous system. [Copyright &y& Elsevier]

Abstract: An IrO2 catalyst was prepared using a colloidal method followed by a thermal treatment. The catalyst was later mixed with Pt-Black and supported on the Sb-doped SnO2 (ATO), synthesized through the same colloidal method. ATO was investigated as a possible catalyst support in an electrode of a regenerative fuel cell (URFC), where Pt–IrO2 was used as the catalyst for the oxygen evolution and reduction reactions. The morphology and composition of the ATO support was investigated through transmission electron microscopy, X-ray diffraction (including Rietveld Refinement), BET analysis, and X-ray fluorescence. An ATO support was obtained with a highly homogeneous distribution and crystal sizes, measuring approximately 4–6 nm. The Pt–IrO2/ATO material was deposited on a Nafion 115 membrane with 0.5 mg cm−2 of catalyst loading. Pt/Vulcan XC-72 (30 wt. %, E-TEK) was used as the catalyst in the H2 compartment with a Pt loading of 0.4 mg cm−2. The electrochemical activity of the Pt–IrO2/ATO for oxygen evolution/reduction in the URFC system was investigated by AC-impedance spectroscopy, linear voltammetry, and chronoamperometry techniques. The maximum mass current activity was 1118 A g−1 at 1.8 V in proton-exchange membrane water electrolyser mode (PEMWE) and 565 A g−1 at 0.3 V in proton-exchange membrane fuel cell mode (PEMFC), both at 80 °C. The value of the round-trip energy efficiency was approximately 48% at 50 A g−1. [Copyright &y& Elsevier]

Abstract: A new generation of highly efficient and non-polluting energy conversion and storage systems is vital to meeting the challenges of global warming and the finite reality of fossil fuels. In this work, nanosized Pt/IrO2 electrocatalysts are synthesized and investigated for the oxygen evolution and reduction reactions in unitized regenerative fuel cells (URFCs). The catalysts are prepared by decorating Pt nanoparticles (2–10 nm) onto the surface of a nanophase IrO2 (7 nm) support using an ultrasonic polyol method. The synthesis procedure allows deposition of metallic Pt nanoparticles on Ir-oxide without causing any occurrence of metallic Ir. The latter is significantly less active for oxygen evolution than the corresponding oxide. This process represents an important progress with respect to the state of the art in this field being the oxygen electrocatalyst generally obtained by mechanical mixing of Pt and IrO2. The nanosized Pt/IrO2 (50:50 wt.%) is sprayed onto a Nafion 115 membrane and used as dual function oxygen electrode, whereas 30 wt.% Pt/C is used as dual function hydrogen electrode in the URFC. Electrochemical activity of the membrane-electrode assembly (MEA) is investigated in a single cell at room temperature and atmospheric pressure both under electrolysis and fuel cell mode to assess the perspectives of the URFC to operate as energy storage device in conjunction with renewable power sources. [Copyright &y& Elsevier]

Abstract: The electrochemical properties of a proton exchange membrane (PEM) stack electrolyzer (9 cells of 100 cm2 geometrical area) were investigated at different temperatures. An amount of H2 of ∼270 l h−1 was produced at 60 A (600 mA cm−2) and 70 °C under 876 W of applied electrical power. The corresponding specific energy consumed in the process was 3.24 Wh·l−1H2. The Faradic and electrical efficiencies were determined. Overall stack efficiencies of 73% and 85%, at 60 A and 70 °C, with respect to the low and high heating value of hydrogen, respectively, were obtained. These results confirmed the successful scale-up of a previous lab-scale device. [Copyright &y& Elsevier]

Abstract: The introduction of inorganic compounds into the Nafion polymeric matrix represents a possible solution to increase the operative temperature (T > 100 °C) without losing the conductivity, water transport properties and above all improving the mechanical characteristics. Two silica materials with different morphologies were synthesized via sol–gel method (SiO2 and SBA-16) by a tetraethyl orthosilicate (TEOS, 98%, Aldrich). Composite Nafion membranes were prepared using a 3%wt/wt of each powder and a standardized casting method. The influence of morphology on chemical–physical properties of membranes was investigated. It was highlighted that the silica introduction reduces the swelling parameters compared to bare Nafion membrane (NRecast) at room temperature. A similar behaviour was observed also in the proton conductivity measurements, in fact values of 0.144 S/cm, 0.114 S/cm and 0.078 S/cm were recorded at 80 °C for NRecast, NSBA-16 and NSiO2 respectively. Polarisation curves carried out at 100 °C have revealed a better performance for composite membranes (NSBA-16) than NRecast with a similar trend of proton conductivity. [Copyright &y& Elsevier]

Abstract: IrO2 electrocatalysts were prepared and electrochemically characterized for the oxygen evolution reaction in a Solid Polymer Electrolyte (SPE) electrolyzer. By using a sulfite complex-based preparation procedure, an amorphous iridium oxide precursor was obtained at 80 °C, which was, successively, calcined at different temperatures: 350 °C, 400 °C and 450 °C. A physico-chemical characterization was carried out by X Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and X-ray-photoelectron spectroscopy (XPS). The various IrO2 catalysts were sprayed onto a Nafion 115 membrane with a loading of 2.5 mg cm−2 to form the anode. A Pt/C catalyst (Pt loading 0.5 mg cm−2) was used as cathode. The best electrochemical performance was obtained for the cell based on the IrO2 calcined at 350 °C. The maximum current density at high potentials (1.8  V) was about 1.75 A cm−2. Accelerated time-tests at 2 A cm−2 demonstrated a suitable stability of the IrO2 calcined at 350 °C; however, the intrinsic stability appeared to increase with the calcination temperature. The sample calcined at 400 °C could represent a good compromise between performance and intrinsic stability. [Copyright &y& Elsevier]

Abstract: The aim of this work is to incorporate inorganic compounds into the Nafion matrix (composite membranes) for high temperature of a polymer electrolyte fuel cell (T cell >100°C). Three silicon oxides having a different morphology were synthesized starting with a tetraethyl orthosilicate as a precursor via sol–gel method: SBA15, SBA15-SH and SiO2. Successively, composite Nafion membranes were prepared using a 3% (w/w) of each powder through a standardized casting method. The influence of SiO2 morphology on chemical–physical properties of the membranes was highlighted resulting in a reduction of the swelling parameters of the composite membranes if compared at T ≥80°C to a recast bare Nafion membrane, used as a reference. Good proton conductivity was also observed for all composite membranes with values of 0.144Scm−1, 0.136Scm−1, 0.090Scm−1and 0.078Scm−1 recorded at 80°C (100% RH) for Nrecast, NSBA15, NSBA15-SH and NSiO2, respectively. The polarisation curves carried out at 120°C (75% RH, 1.5abs.bar) have revealed a higher stability for NSBA15 membrane after a short time-test, probably because the silica morphology is able to retain water within the polymer matrix and, in accordance to the swelling data. [Copyright &y& Elsevier]

Abstract: An optimization study of components and assembling characteristics for a proton exchange membrane (PEM) short stack electrolyzer (3 cells of 100 cm2 geometrical area) was carried out. The electrochemical properties were investigated by polarization, impedance spectroscopy and chrono-potentiometric measurements. A decrease of the ohmic contact resistance between the bipolar plates and the electrode backing layer was obtained by using an appropriate thickness for the gas diffusion layers/current collectors as well as by an optimization of stack compression. The amount of H2 produced was ∼90 l h−1 at 60 A (600 mA cm−2) and 75 °C under 300 W of applied electrical power. No significant leakage or gas recombination was observed. The stack electrical efficiency was 75% and 88%, at 60 A and 75 °C, with respect to the low and high heating value of hydrogen, respectively. [Copyright &y& Elsevier]

Abstract: A nanosized IrO2 anode electrocatalyst was prepared by a sulfite-complex route for application in a proton exchange membrane (PEM) water electrolyzer. The physico-chemical properties of the IrO2 catalyst were studied by termogravimetry–differential scanning calorimetry (TG–DSC), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The electrochemical activity of this catalyst for oxygen evolution was investigated in a single cell PEM electrolyzer consisting of a Pt/C cathode and a Nafion® membrane. A current density of 1.26Acm−2 was obtained at 1.8V and a stable behavior during steady-state operation at 80°C was recorded. The Tafel plots for the overall electrochemical process indicated a slope of about 80mVdec−1 in a temperature range from 25°C to 80°C. The kinetic and ohmic activation energies for the electrochemical process were 70.46kJmol−1 and 13.45kJmol−1, respectively. A short stack (3 cells of 100cm2 geometrical area) PEM electrolyzer was investigated by linear voltammetry, impedance spectroscopy and chrono-amperometric measurements. The amount of H2 produced was 80lh−1 at 60A under 330W of applied electrical power. The stack electrical efficiency at 60A and 75°C was 70% and 81% with respect to the low and high heating value of hydrogen, respectively. [Copyright &y& Elsevier]

Abstract: An investigation of carbon-supported Pt/C and PtCo/C catalysts was carried out with the aim to evaluate their stability under high temperature polymer electrolyte membrane fuel cell (PEMFC) operation. Carbon-supported nanosized Pt and PtCo particles with a mean particle size between 1.5nm and 3nm were prepared by using a colloidal route. A suitable degree of alloying was obtained for the PtCo catalyst by using a carbothermal reduction. The catalyst stability was investigated to understand the influence of carbon black corrosion, platinum dissolution and sintering in gas-fed sulphuric acid electrolyte half-cell at 75°C and in PEMFC at 130°C. Electrochemical active surface area and catalyst performance were determined in PEMFC at 80°C and 130°C. A maximum power density of about 700mWcm−2 at 130°C and 3bar abs. O2 pressure with 0.3mgPtcm−2 loading was achieved. The PtCo alloy showed a better stability than Pt in sulphuric acid after cycling; yet, the PtCo/C catalyst showed a degradation after the carbon corrosion test. The PtCo/C catalyst showed smaller sintering effects than Pt/C after accelerated degradation tests in PEMFC at 130°C. [Copyright &y& Elsevier]

Abstract: A nanocomposite re-cast Nafion hybrid membrane containing titanium oxide calcined at T =400°C as an inorganic filler was developed in order to work at medium temperature in polymer electrolyte fuel cells (PEFCs) maintaining a suitable membrane hydration under fuel cell operative critical conditions. Nanometre TiO2 powder was synthesized via a sol–gel procedure by a rapid hydrolysis of Ti(OiPr)4. The membrane was prepared by mixing a Nafion–dimethylacetammide (DMAc) dispersion with a 3wt% of TiO2 powder and casting the mixture by Doctor Blade technique. The resulting film was characterised in terms of water uptake and ion exchange capacity (IEC). The membrane was tested in a single cell from 80 to 130°C in humidified H2/air. The obtained results were compared with the commercial Nafion115 and a home-made recast Nafion membrane. Power density values of 0.514 and 0.256Wcm−2 at 0.56V were obtained at 110 and 130°C, respectively, for the composite Nafion–Titania membrane. Preliminary tests carried out using steam reforming (SR) synthetic fuel at about 110°C have highlighted the benefit of the inorganic filler introduction when PEFC operates at medium temperature and with processed hydrogen. [Copyright &y& Elsevier]

Here we present a study that explores the feasibility, user engagement, and usability of an interactive system that involves the use of tangible objects with various shapes and properties to interact with virtual tasks designed for upper limb rehabilitation following a stroke. We evaluated five different types of interaction modalities, including three grasps modalities (power grasp, lateral grasp and tripod grasp) and two strength modalities. These were tested using five basic game-like tasks with a total of 20 stroke patients. High levels of enjoyment were reported, and the system overall was considered feasible. The usability mean score (63.3) was acceptable for a system still in development. Enabling the use of tangibles during serious games in rehabilitation settings can enhance the transfer of learning to real-world situations., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Fabio Pereira reports financial support was provided by Foundation for Science and Technology. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Background: Cecal perforation from barotrauma is a rare complication of colonoscopy, even with the use of CO₂ insufflation, which is generally preferred over room air due to its rapid absorption and reduced patient discomfort., Case Report: A 64-year-old woman with hypertension and dyslipidemia underwent a routine colonoscopy with CO₂ insufflation. Multiple diverticula were noted, and upon reaching the cecum, several parallel linear lesions with spontaneous bleeding, consistent with "cat scratch" colon, were observed. Hemostasis was achieved with 10 endoscopic clips. A subsequent CT scan revealed pneumoperitoneum and the clips in the cecum. The patient was managed conservatively with bowel rest and intravenous antibiotics, showing a favorable clinical course and was discharged on the fifth day., Discussion: This case highlights the potential for cecal perforation due to barotrauma even with CO₂ insufflation during colonoscopy, emphasizing the need for awareness and prompt management of such complications.

Background: Lung and colon cancers are among the most prevalent and lethal malignancies worldwide, underscoring the urgent need for advanced diagnostic methodologies. This study aims to develop a hybrid deep learning and machine learning framework for the classification of Colon Adenocarcinoma, Colon Benign Tissue, Lung Adenocarcinoma, Lung Benign Tissue, and Lung Squamous Cell Carcinoma from histopathological images., Methods: Current approaches primarily rely on the LC25000 dataset, which, due to image augmentation, lacks the generalizability required for real-time clinical applications. To address this, Contrast Limited Adaptive Histogram Equalization (CLAHE) was applied to enhance image quality, and 1000 new images from the National Cancer Institute GDC Data Portal were introduced into the Colon Adenocarcinoma, Lung Adenocarcinoma, and Lung Squamous Cell Carcinoma classes, replacing augmented images to increase dataset diversity. A hybrid feature extraction model combining MobileNetV2 and EfficientNetB3 was optimized using the Grey Wolf Optimizer (GWO), resulting in the Lung and Colon histopathological classification technique (MEGWO-LCCHC). Cross-validation and hyperparameter tuning with Optuna were performed on various machine learning models, including XGBoost, LightGBM, and CatBoost., Results: The MEGWO-LCCHC technique achieved high classification accuracy, with the lightweight DNN model reaching 94.8%, LightGBM at 93.9%, XGBoost at 93.5%, and CatBoost at 93.3% on the test set., Conclusions: The findings suggest that our approach enhances classification performance and offers improved generalizability for real-world clinical applications. The proposed MEGWO-LCCHC framework shows promise as a robust tool in cancer diagnostics, advancing the application of AI in oncology.

Diabetes mellitus, a chronic condition affecting millions worldwide, necessitates continuous monitoring of blood glucose level (BGL). The increasing prevalence of diabetes has driven the development of non-invasive methods, such as electronic noses (e-noses), for analyzing exhaled breath and detecting biomarkers in volatile organic compounds (VOCs). Effective machine learning models require extensive patient data to ensure accurate BGL predictions, but previous studies have been limited by small sample sizes. This study addresses this limitation by employing conditional generative adversarial networks (CTGAN) to generate synthetic data from real-world tests involving 29 healthy and 29 diabetic participants, resulting in over 14,000 new synthetic samples. These data were used to validate machine learning models for diabetes detection and BGL prediction, integrated into a Tiny Machine Learning (TinyML) e-nose system for real-time analysis. The proposed models achieved an 86% accuracy in BGL identification using LightGBM (Light Gradient Boosting Machine) and a 94.14% accuracy in diabetes detection using Random Forest. These results demonstrate the efficacy of enhancing machine learning models with both real and synthetic data, particularly in non-invasive systems integrating e-noses with TinyML. This study signifies a major advancement in non-invasive diabetes monitoring, underscoring the transformative potential of TinyML-powered e-nose systems in healthcare applications.

The partial replacement effect of Portland cement by geothermal nano-SiO 2 waste (GNSW) for sustainable Portland-cement-based concrete was investigated to improve the properties of concrete exposed at high critical temperatures. Portland cement was partially replaced by 20 and 30 wt.% of GNSW. The partial replacement effect on Portland-cement-based concrete subjected to 350, 550, and 750 °C was evaluated by measuring the weight changes, ultrasonic pulse velocity, thermogravimetric and differential thermal analysis, X-ray diffraction, surface inspection, and scanning electron microscopy under residual conditions. The ultrasonic pulse velocity results showed that the GNSW specimens maintained suitable stability after being heated to 350 °C. The SEM analysis revealed a denser microstructure for the 20 wt.% of partial replacement of Portland cement by GNSW specimen compared to the reference concrete when exposed to temperatures up to 400 °C, maintaining stability in its microstructure. The weight losses were higher for the specimens with partial replacements of GNSW than the reference concrete at 550 °C, which can be attributed to the pozzolanic activity presented by the GNSW, which increases the amounts of CSH gel, leading to a much denser cementitious matrix, causing a higher weight loss compared to the reference concrete. GNSW is a viable supplementary cementitious material, enhancing thermal properties up to 400 °C due to its high pozzolanic activity and filler effect while offering environmental benefits by reducing industrial waste.

Volatile organic compounds (VOCs) in exhaled human breath serve as pivotal biomarkers for disease identification and medical diagnostics. In the context of diabetes mellitus, the noninvasive detection of acetone, a primary biomarker using electronic noses (e-noses), has gained significant attention. However, employing e-noses requires pre-trained algorithms for precise diabetes detection, often requiring a computer with a programming environment to classify newly acquired data. This study focuses on the development of an embedded system integrating Tiny Machine Learning (TinyML) and an e-nose equipped with Metal Oxide Semiconductor (MOS) sensors for real-time diabetes detection. The study encompassed 44 individuals, comprising 22 healthy individuals and 22 diagnosed with various types of diabetes mellitus. Test results highlight the XGBoost Machine Learning algorithm's achievement of 95% detection accuracy. Additionally, the integration of deep learning algorithms, particularly deep neural networks (DNNs) and one-dimensional convolutional neural network (1D-CNN), yielded a detection efficacy of 94.44%. These outcomes underscore the potency of combining e-noses with TinyML in embedded systems, offering a noninvasive approach for diabetes mellitus detection.