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In this paper, dry etched vertical nanowires (VNWs) are used in transmission line/transfer length analysis to study the contacts of gate-all-around devices for future technology nodes. VNW resistors with Mo and Pd based metal stack contacts to p-InGaAs show Schottky behavior, unlike the planar counterpart. The resistance for Mo contact is higher than Pd, however, Pd was found to form an alloy with InGaAs at temperatures as low as 190 °C, and the length of Pd diffusion into the InGaAs increased at smaller NW dimensions, hindering future scalability. The minimum extracted specific contact resistivity (ρC) values are 1.6 × 10−5 Ω cm2 (Mo) and 4.2 × 10−6 Ω cm2 (Pd) for a doping level of 1 × 1019 cm−3. An apparent dependence of ρC on the NW diameter was also observed. This has been attributed to the surface states under the un-gated region of NW devices and found to dominate at smaller diameters. An analytical model to account for such geometrical effects has also been developed and validated with technology computer-aided design simulations. The analysis presented in this paper effectively captures the 3D aspects of an NW contact at nanoscale dimensions and can be applied irrespective of the semiconductor and contact metal used. [ABSTRACT FROM AUTHOR]

Mycotoxins represent a significant hazard to human and animal health, prompting extensive research into mitigating their detrimental impacts. This study focuses on aflatoxin B1 (AFB1) and ochratoxin A (OTA), both tightly regulated in Europe due to their severe toxicological effects. The aim of this study was to investigate the potential benefits of carotenoids encapsulated in nanostructured lipid carriers (NLCs) on the bioaccessibility, bioavailability, and cellular damage induced by these two mycotoxins. For the experimental design, a lyophilized formulation of carotenoid-loaded NLCs was subjected to an in vitro digestion, combined with two different types of fungal-contaminated bread. Intestinal digests were analyzed via HPLC coupled with fluorescence detection. Regarding bioaccessibility assessments, results revealed no significant differences between digests from bread with and without NLCs for both AFB1 (1.36 ± 0.08 mg/L vs. 1.39 ± 0.04 mg/L) and OTA (1.33 ± 0.03 mg/L vs. 1.46 ± 0.01 mg/L). For bioavailability, Caco-2 intestinal cells differentiated for 21-days on transwells supports, were exposed to the different intestinal digests for 4 hours. AFB1 concentrations were 0.39 ± 0.12 mg/L without NLCs and 0.44 ± 0.04 mg/L with NLCs, while OTA concentrations were 0.44 ± 0.14 mg/L without NLCs and 0.41 ± 0.02 mg/L with NLCs; showing also for bioavailability no significant differences. Cell viability assays using MTT assay showed no improvement in AFB1-exposed cells with NLCs, while OTA-exposed cells exhibited increased viability from 11% to 22% at 48 hours and from 9% to 13% at 72 hours when NLCs were present in the intestinal digest. In summary, NLCs did not affect mycotoxin bioaccessibility or bioavailability but slightly enhanced cellular survival in OTA-exposed cells. These findings highlight the complex interplay between carotenoids and mycotoxin dynamics, suggesting potential strategies for mycotoxin toxicity mitigation. [ABSTRACT FROM AUTHOR]

Capacitance-voltage (C-V) and capacitance-frequency (C-f) measurements are performed on atomic layer deposited TiO2 thin films with top and bottom Au and Pt electrodes, respectively, over a large temperature and frequency range. A sharp capacitance peak/discontinuity (C-V anomalous) is observed in the C-V characteristics at various temperatures and voltages. It is demonstrated that this phenomenon is directly associated with oxygen vacancies. The C-V peak irreversibility and dissymmetry at the reversal dc voltage are attributed to difference between the Schottky contacts at the metal/TiO2 interfaces. Dielectric analyses reveal two relaxation processes with degeneration of the activation energy. The low trap level of 0.60-0.65 eV is associated with the first ionized oxygen vacancy at low temperature, while the deep trap level of 1.05 eV is associated to the second ionized oxygen vacancy at high temperature. The DC conductivity of the films exhibits a transition temperature at 200 °C, suggesting a transition from a conduction regime governed by ionized oxygen vacancies to one governed by interstitial Ti3+ ions. Both the C-V anomalous and relaxation processes in TiO2 arise from oxygen vacancies, while the conduction mechanism at high temperature is governed by interstitial titanium ions. [ABSTRACT FROM AUTHOR]

Acid catalysis plays an important role in biomass conversion processes for producing chemicals and fuels. We report a relatively simple procedure for synthesizing versatile, strong acid catalysts based on carbon and carbon-silica composites with sulfonic acid groups. The process involves chemical activation of a sulfonic acid organic precursor at low temperature. The synthesis conditions can be modified to tune the surface composition, texture, and the acid properties of the materials towards superior catalytic performances. Molecular level insights into the nature and strength of the acid sites were gained by combining high resolution XPS and 1H-decoupled 31P MAS NMR spectroscopy of adsorbed triethylphosphine oxide. These materials are effective acid catalysts for the conversion of different biomass-derived chemicals to useful bio products such as furanic ethers and levulinate esters. [ABSTRACT FROM AUTHOR]

Electrostatic force microscopy (EFM) allows measurement of tiny changes in tip-sample capacitance. When nanoobjects are studied by EFM, they only contribute a very small fraction of the total capacitance between the tip and the sample. We show that the analysis of 3D maps of the EFM signal allows extracting the contribution of the nanomaterial to the total capacitance. This opens the way to applications of EFM as a measure of the dielectric coefficient of electrically insulating nanomaterials or the quantum capacitance of conducting nanomaterials. We apply this method to study the charge response of magnetite, Fe3O4, nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: The preparation, characterization and sensing properties of CNT composites with a thin metal oxide (MOx) surface layer is presented. Atomic layer deposition (ALD) was applied for the coating of the inner and outer CNTs walls with thin films of ZnO and SnO2 of precisely controlled thicknesses. Differently treated CNTs with different degree of surface functionalization were used as support for the oxide films. The sensing properties of the obtained composite materials towards NO2 were investigated and related to the morphological and microstructural characteristics of both the coating and support. SnO2-based composites on CNTs treated at 700°C show enhanced performance as sensors, making them suitable for practical applications. [Copyright &y& Elsevier]

A study over Sb-promoted tin oxide nanopowders for sensing applications is reported. SnO2 nanopowders pure and promoted with 5wt% of antimony were prepared by wet chemical methods and widely characterized by TEM, XRD, and XPS techniques. Thick film resistive sensors were fabricated by depositing the synthesized nanopowders by drop-coating on interdigited alumina substrates. The sensing characteristics of the pure SnO2 and Sb-promoted sensors for the monitoring of trace level of NO2 were studied. The response of the sensors to water vapor was also investigated, revealing that Sb acts favorably eliminating the interference of humidity. [ABSTRACT FROM AUTHOR]

Titania and hafnia thin films were deposited by atomic layer deposition using metal alkoxides and carboxylic acids as oxygen source. The effect of annealing under nitrogen on the densification of the films and on the resulting electrical properties is presented. The as-deposited and annealed films demonstrate good dielectric permittivity and low leakage current densities due to their purity and amorphous character. [ABSTRACT FROM AUTHOR]

We present a tunnel spectroscopy study of the electronic spectrum of single magnetite Fe3O4 nanoparticles trapped between nanometer-spaced electrodes. The Verwey transition is clearly identified in the current-voltage characteristics where we find that the transition temperature is electric field dependent. The data show the presence of localized states at high energy, ε ~ 0.6 eV, which can be attributed to polaron states. At low energy, the density of states (DOS) is suppressed at the approach of the Verwey transition. Below the Verwey transition, a gap, Δ ~ 300 meV, is observed in the spectrum. In contrast, no gap is observed in the high temperature phase, implying that electronic transport in this phase is possibly due to polaron hopping with activated mobility. [ABSTRACT FROM AUTHOR]

Spinel-structured transition metal (TM) oxides have shown great potential as a sustainable alternative to platinum group metal-based electrocatalysts. Among them, high-entropy oxides (HEOs) with multiple TM-cation sites are suitable for engineering octahedral redox-active centers to enhance the catalyst reactivity. This paper reports on the preparation of electrospun (Cr 1/5 Mn 1/5 Fe 1/5 Co 1/5 Ni 1/5 ) 3 O 4 nanofibers (NFs) and their evaluation as electrocatalysts. Its main aim is to unveil the nanostructural features that play a key role in the alkaline oxygen evolution reaction. Differing calcination temperature (300-800 °C) and duration (2 or 4 h) leads to different morphology of the NFs, crystallinity of the oxide, density of defects, and cation distribution in the lattice, which reflect in different electrocatalytic behaviors. The best performance (overpotential and Tafel slope at 10 mA cm -2 : 325 mV and 40 mV dec -1 , respectively) pertains to the NFs calcined at 400 °C for 2 h. To gain a deeper understanding of their electrocatalytic properties, the pristine NFs are investigated by a combination of analytical techniques. In particular, broadband electric spectroscopy reveals that the mobility of oxygen vacancies in the best electrocatalyst is associated to very fast local dielectric relaxations of metal coordination octahedral geometries and experimentally demonstrates the key role of O-deficient octahedra., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus ochraceous and various Penicillium species, which are known for contaminating agricultural products and posing significant health risks, which include immunotoxicity. This study aims to evaluate the potential of nanostructured lipid carriers (NLCs) loaded with a carotenoid-enriched extract from pumpkin peel ( Cucurbita maxima L.) in mitigating the toxic effects of OTA. To address the poor bioavailability and instability of carotenoids, nanoencapsulation techniques were employed to enhance their delivery and efficacy. NLCs were formulated using hydrogenated sunflower oil, pumpkin oil, and soy lecithin using hot high-pressure homogenization. The in vitro study involved co-digesting OTA-contaminated bread with an NLC formulation and assessing the impact of the encapsulated carotenoid on OTA bioaccessibility, bioavailability, and cellular toxicity using Caco-2 and Jurkat T cells. Even though no significant influence was observed on the bioaccessibility and bioavailability of OTA, carotenoid-loaded NLCs exhibited cytoprotective effects by improving cell viability and mitigating OTA-induced toxicity in both Caco-2 and Jurkat T cells. Particularly, the flow cytometry analysis highlighted the ability of carotenoids to mitigate OTA-induced cellular damage by decreasing ROS production and limiting mitochondrial mass changes. The study suggests that the encapsulation of carotenoids in NLCs represents a promising strategy to enhance their protective effects against OTA toxicity, potentially offering a novel approach to food safety and public health protection. The study underscores the potential of nanotechnology in improving the bioavailability and efficacy of natural antioxidants to mitigate mycotoxin-induced damage.

Plants, including pumpkins ( Cucurbita spp.), are an interesting source of nutrients and bioactives with various health benefits. In this research, carotenoid extracts obtained from the pulp of eight pumpkin varieties, belonging to the C. moschata and C. maxima species, were tested for cytotoxicity on SH-SY5Y neuroblastoma cells. The results showed that pumpkin bioactives exert a cytotoxic action against the tested cells, in particular Butternut extract at a 100 μM (53.69 μg/mL) concentration after 24 h of treatment and Mantovana extract at 50 μM (26.84 μg/mL) after 48 h. Moreover, the carotenoid extracts also showed interesting in vitro antioxidant activity, evaluated by ABTS and ORAC assays. To fully characterize the qualitative and quantitative profile of carotenoids in the tested extracts, a high-performance chromatographic technique was performed, revealing that pumpkin pulp carotenoids were mainly represented by β-carotene, mono- and di-esterified hydroxy- and epoxy-carotenoids. Moreover, the carotenoid dataset was also useful for discriminating samples from two different species. In conclusion, the results of the present study highlight the potential anti-cancer activity of pumpkin carotenoid extracts and the possibility of using them as chemotherapeutic adjuvants.

The side reactions and dendrite growth at the interface of Zn anodes greatly limit their practical applications in Zn metal batteries. Herein, we propose a hybrid molecular sieve-based interfacial layer (denoted as Z 7 M 3 ) with a hierarchical porous structure for Zn metal anodes, which contains 70 vol % microporous ZSM-5 molecular sieves and 30 vol % mesoporous MCM-41 molecular sieves. Through comprehensive molecular dynamics simulations, we demonstrate that the mesopores (∼2.5 nm) of MCM-41 can limit the disordered diffusion of free water molecules and increase the wettability of the interfacial layer toward aqueous electrolytes. In addition, the micropores (∼0.56 nm) of ZSM-5 can optimize the Zn 2+ solvation structures by reducing the bonded water molecules, which simultaneously decrease the constraint force of solvated water molecules to Zn 2+ ions, thus promoting the penetrability and diffusion kinetics of Zn 2+ ions in Z 7 M 3 . The synergetic effects from the hybrid molecular sieves maintain a constant Zn 2+ concentration on the surface of the Zn electrode during Zn deposition, contributing to dendrite-free Zn anodes. Consequently, Z 7 M 3 -coated Zn electrodes achieved excellent cycling stability in both half and full cells.

Lithium-ion batteries, essential for electronics and electric vehicles, predominantly use cathodes made from critical materials like cobalt. Sulfur-based cathodes, offering a high theoretical capacity of 1675 mAh g -1 and environmental advantages due to sulfur's abundance and lower toxicity, present a more sustainable alternative. However, state-of-the-art sulfur-based electrodes do not reach the theoretical capacities, mainly because conventional electrode production relies on mixing of components into weakly coordinated slurries. Consequently, sulfur's mobility leads to battery degradation-an effect known as the "sulfur-shuttle". This study introduces a solution by developing a microporous, covalently-bonded, imine-based polymer network grown in situ around sulfur particles on the current collector. The polymer network (i) enables selective transport of electrolyte and Li-ions through pores of defined size, and (ii) acts as a robust host to retain the active component of the electrode (sulfur species). The resulting cathode has superior rate performance from 0.1 C (1360 mAh g -1 ) to 3 C (807 mAh g -1 ). Demonstrating a high-performance, sustainable sulfur cathode produced via a simple one-pot process, our research underlines the potential of microporous polymers in addressing sulfur diffusion issues, paving the way for sulfur electrodes as viable alternatives to traditional metal-based cathodes., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Ultrasound-assisted extraction of (poly)phenols from pumpkin pulp was optimized using response surface methodology. Time, solvent-to-sample ratio and percentage of water in ethanol were considered and a full factorial design was applied. The optimized conditions (10 min; 30 mL/g; 50% water in ethanol) were used to isolate (poly)phenols from five pumpkin varieties (Hokkaido, Lunga di Napoli, Mantovana, Moscata di Provenza, Violina rugosa), collected for two successive years. Phenolic acids were the most abundant phenolic class (gallic acid up to 413.50 μg/g), even if differences were observed among varieties and harvesting years. Generally, Violina rugosa harvested in 2021 showed the highest total phenol content (7.59 mg gallic acid equivalents/g) and antioxidant properties (16.93 mg Trolox equivalents/g). All pumpkin variety exhibited antimicrobial activity within a concentration range of 1.95 to 250 μg/mL. In conclusion, the pumpkin pulp can be considered a promising natural source of (poly)phenols for the development of health-promoting products., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The Stöber method is a widely-used sol-gel route for synthesizing amorphous SiO 2 colloids and conformal coatings. However, the material systems compatible with this method are still limited. Herein, we have extended the approach to metal-organic frameworks (MOFs) and coordination polymers (CPs) by mimicking the Stöber method. We introduce a general synthesis route to amorphous MOFs or CPs by making use of a base-vapor diffusion method, which allows to precisely control the growth kinetics. Twenty-four different amorphous CPs colloids were successfully synthesized by selecting 12 metal ions and 17 organic ligands. Moreover, by introducing functional nanoparticles (NPs), a conformal amorphous MOFs coating with controllable thickness can be grown on NPs to form core-shell colloids. The versatility of this amorphous coating technology was demonstrated by synthesizing over 100 core-shell composites from 20 amorphous CPs shells and over 30 different NPs. Besides, various multifunctional nanostructures, such as conformal yolk-amorphous MOF shell, core@metal oxides, and core@carbon, can be obtained through one-step transformation of the core@amorphous MOFs. This work significantly enriches the Stöber method and introduces a platform, enabling the systematic design of colloids exhibiting different level of functionality and complexity., (© 2024. The Author(s).)

Metal Organic Frameworks (MOFs) are organic-inorganic hybrid materials with exceptionally customizable composition and properties. MOFs intrinsically possess open metal sites, tunable pore size/shape and an ultra-large specific surface area, and have obtained significant attention over the past 30 years. Furthermore, through the integration of functional moieties such as, molecules, functional groups, noble metal clusters and nanocrystals or nanoparticles into MOFs, the resulting composites have greatly enriched the physical and chemical properties of pure MOFs, enabling their application in a wider range of fields. Triethylamine (TEA) as an organic base has consistently played a fundamental role in the development of MOFs. In this Concept, the versatility of triethylamine when involved in the synthesis of MOFs is discussed. Four sections are used to elaborate on the role of TEA including: (1) Single crystal synthesis; (2) Size and morphology control; (3) Counterion of MOFs; (4) MOFs composites synthesis. In the last part, we highlight the potential of TEA for further developments., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

This study shows that the simple approach of keeping anodic TiO 2 nanotubes at 70 °C in ethanol for 1 h results in improved photoelectrochemical water splitting activity due to initiation of crystallization in the material amplified by the light-induced formation of a Ti 3+ -V o states under UV 365 nm illumination. For the first time, the light-induced Ti 3+ -V o states are generated when oxygen is present in the reaction solution and are stable when in contact with air (oxygen) for a long time (two months). We confirmed here that the amorphous or nearly amorphous structure of titania supports the survival of Ti 3+ species in contact with oxygen. It is also shown that the ethanol treatment substantially improves the morphology of the titania nanotube arrays, specifically, less surface cracking and surface purification from C- and F-based contamination from the electrolyte used for anodizing., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The realization of large-scale industrial application of alkaline water electrolysis for hydrogen generation is severely hampered by the cost of electricity. Therefore, it is currently necessary to synthesize highly efficient electrocatalysts with excellent stability and low overpotential under an industrial-level current density. Herein, Ir-incorporated in partially oxidized Ru aerogel has been designed and synthesized via a simple in situ reduction strategy and subsequent oxidation process. The electrochemical measurements demonstrate that the optimized Ru 98 Ir 2 -350 electrocatalyst exhibits outstanding hydrogen evolution reaction (HER) performance in an alkaline environment (1 M KOH). Especially, at the large current density of 1000 mA cm -2 , the overpotential is as low as 121 mV, far exceeding the benchmark Pt/C catalyst. Moreover, the Ru 98 Ir 2 -350 catalyst also displays excellent stability over 1500 h at 1000 mA cm -2 , denoting its industrial applicability. This work provides an efficient route for developing highly active and ultra-stable electrocatalysts for hydrogen generation under industrial-level current density., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Dural arteriovenous fistulas (DAVFs) are intracranial vascular abnormalities in which one or more meningeal arteries shunt into a venous structure, either a cortical vein or a venous sinus, causing cerebral venous hypertension and risk of haemorrhage. Imaging diagnosis and characterisation are of paramount importance to grade the haemorrhagic risk and direct management. Non-invasive vascular neuroimaging might pose a diagnostic suspicion, but invasive catheter digital subtraction angiography (DSA) is usually required. We present the case of a patient with an atypical acute cerebral haemorrhage in which admission imaging with CT angiography (CTA) and MR angiography (MRA) was unremarkable, while advanced morphological MR with susceptibility-weighted imaging (SWI) revealed specific findings suggesting unilateral chronic venous hypertension. Successively, DSA detected a small DAVF that was treated with endovascular embolization. This case report raises awareness on subtle but important conventional imaging findings that suggest the presence of an AV shunt, to avoid misdiagnosis and delayed treatment., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

The integration of metal oxide nanomaterials with mesoporous silica is a promising approach to exploiting the advantages of both types of materials. Traditional synthesis methods typically require multiple steps. This work instead presents a fast, one-step, template-free method for the synthesis of metal oxides homogeneously dispersed within mesoporous silica, including oxides of W, Ti, Nb, Ta, Sn, and Mo. These composites have tunable metal oxide contents, large surface areas, and wide mesopores. The combination of Nb 2 O 5 nanoparticles (NPs) with SiO 2 results in an increased surface area and a larger number of acid sites compared to pure Nb 2 O 5 NPs. The surface texture and acidity of the silica-niobia composites can be tuned by adjusting the Nb/Si molar ratio. Moreover, the silica provides protection to the niobia NPs, preventing sintering during thermal treatment at 400 °C. The silica-niobia materials exhibit superior performance as catalysts in the aldol condensation of furfural (Fur) with acetone compared to pure niobia, leading to an up to 62% in product yield. Additionally, these catalysts show remarkable stability, retaining their performance over multiple runs. This work demonstrates the potential of the proposed synthesis approach for preparing more sustainable, high-performance, durable, and stable nanoscale metal oxide-based catalysts with a tunable composition, surface area, and active site density.

Pumpkin ( Cucurbita sp.) represents an unquestionable source of valuable nutrients and bioactive compounds having a broad spectrum of health-promoting effects. The goal of this work was to characterize the byproducts (peels and filaments) of different pumpkin varieties belonging to C. moschata (Butternut, Lunga di Napoli, Moscata di Provenza, and Violina rugosa) and C. maxima (Delica, Delica vanity, Hokkaido, and Mantovana) species in terms of total carotenoid content, antioxidant activity, and carotenoid profiling. The research revealed that peels and filaments were a good source of β-carotene and other non-esterified carotenoids, as well as esterified carotenoids. Considering the growing market demand for safe and healthy food products, pumpkin byproducts, having also an interesting antioxidant bioactivity, could be useful in the development of novel functional products.

High-entropy oxides (HEOs) have emerged as promising anode materials for next-generation lithium-ion batteries (LIBs). Among them, spinel HEOs with vacant lattice sites allowing for lithium insertion and diffusion seem particularly attractive. In this work, electrospun oxygen-deficient (Mn,Fe,Co,Ni,Zn) HEO nanofibers are produced under environmentally friendly calcination conditions and evaluated as anode active material in LIBs. A thorough investigation of the material properties and Li + storage mechanism is carried out by several analytical techniques, including ex situ synchrotron X-ray absorption spectroscopy. The lithiation process is elucidated in terms of lithium insertion, cation migration, and metal-forming conversion reaction. The process is not fully reversible and the reduction of cations to the metallic form is not complete. In particular, iron, cobalt, and nickel, initially present mainly as Fe 3+ , Co 3+ /Co 2+ , and Ni 2+ , undergo reduction to Fe 0 , Co 0 , and Ni 0 to different extent (Fe < Co < Ni). Manganese undergoes partial reduction to Mn 3+ /Mn 2+ and, upon re-oxidation, does not revert to the pristine oxidation state (+4). Zn 2+ cations do not electrochemically participate in the conversion reaction, but migrating from tetrahedral to octahedral positions, they facilitate Li-ion transport within lattice channels opened by their migration. Partially reversible crystal phase transitions are observed., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)

Herein, we report the study of atomically precise Au x Ag 25- x nanoclusters (NCs) toward photocatalytic hydrogen evolution. The incorporation of Au atoms into Ag 25 NCs not only narrowed the HOMO-LUMO gaps but also created an interstitial Au-Ag microenvironment, which promoted the photogenerated charge carrier utilization and optimized the reaction dynamics.

CuO-based nanostructures have been widely investigated in catalysis, sensing, and energy conversion and storage in recent years. The unique properties of these nanostructures are largely related to the morphology and crystallinity of CuO. The controlled deposition of conformal CuO thin films by atomic layer deposition (ALD) has remained challenging until now owing to the limited understanding of the nucleation behavior and growth process. Here, a novel ALD process for copper oxide was developed using copper(II) trifluoroacetylacetonate [Cu(tfacac) 2 ] as the metal precursor. The nucleation and initial growth of a CuO film are strongly dependent on the surface OH concentration. A continuous particulate-like CuO film was grown on OH-abundant pristine SiO 2 particles, whereas the surface of the annealed SiO 2 particles (presenting mostly isolated OH groups) remained uncoated under the same growth conditions. Moreover, a uniform and conformal CuO film was grown on covalently functionalized CNTs under identical conditions as pristine SiO 2 particles. This study provides a strategy for tailoring the structure and the properties of thin films via ALD, which is promising for designing well-tailored nanostructures for various applications.

Metal oxide semiconductor (MOS) thin films are of critical importance to both fundamental research and practical applications of gas sensors. Herein, a high-performance H 2 sensor based on palladium (Pd) and rhodium (Rh) co-functionalized Fe 2 O 3 films with an ultrathin thickness of 8.9 nm deposited by using atomic layer deposition is reported. The sensor delivers an exceptional response of 105.9 toward 10 ppm H 2 at 230 °C, as well as high selectivity, immunity to humidity, and low detection limit (43 ppb), which are superior to the reported MOS sensors. Importantly, the Fe 2 O 3 film sensor under dynamic H 2 detection is for the first time observed by operando transmission electron microscopy, which provides deterministic evidence for structure evolution of MOS during sensing reactions. To further reveal the sensing mechanism, density functional theory calculations are performed to elucidate the sensitization effect of PdRh catalysts. Mechanistic studies suggest that Pd promotes the adsorption and dissociation of H 2 to generate PdH x , while Rh promotes the dissociation of oxygen adsorbed on the surface, thereby jointly promoting the redox reactions on the films. A wireless H 2 detection system is also successfully demonstrated using the thin film sensors, certifying a great potential of the strategy to practical sensors., (© 2023 Wiley-VCH GmbH.)

Levonorgestel intrauterine devices are safe contraceptive methods, with even medical indications. However, they may present rare, but severe complications such as perforation and abdominal dislocation. Ultrasound assessment may be limited if a medicate intrauterine device is lost, due to its particular echogenicity. We report cases complicated by loss of intrauterine devices. Based on this experience we believe that ultrasound should always be associated to an X-ray examination to prevent misdiagnosis, especially in case of loss of a levonorgestrel device. Although our conclusions are not innovative and the cases are limited, we believe they can be a reminder in clinical practice to avoid not so infrequent complications and clinical errors. We would also like to recall the limitations of ultrasound in locating levonorgestrel intra uterine devices and stress that one should never take for granted the expulsion of the device in case of lost its threads., (© 2023. Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB).)

Chiral inorganic superstructures have received considerable interest due to the chiral communication between inorganic compounds and chiral organic additives. However, the demanding fabrication and complex multilevel structure seriously hinder the understanding of chiral transfer and self-assembly mechanisms. Herein, we use chiral CuO superstructures as a model system to study the formation process of hierarchical chiral structures. Based on a simple and mild synthesis route, the time-resolved morphology and the in situ chirality evolution could be easily followed. The morphology evolution of the chiral superstructure involves hierarchical assembly, including primary nanoparticles, intermediate bundles, and superstructure at different growth stages. Successive redshifts and enhancements of the CD signal support chiral transfer from the surface penicillamine to the inorganic superstructure. Full-field electro-dynamical simulations reproduced the structural chirality and allowed us to predict its modulation. This work opens the door to a large family of chiral inorganic materials where chiral molecule-guided self-assembly can be specifically designed to follow a bottom-up chiral transfer pathway., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)