National Institute for Research and Development in Microtechnologies

This study presents an innovative upcycling methodology for the production of rigid polyurethane (PUR) foams using a biopolyol (BioPol) synthesized from corn cob lignocellulose waste. The BioPol was obtained through microwave-assisted (MW) irradiation under acidic catalysis, followed by neutralization of the acidic medium. Rheological characterization of the lignocellulose-derived BioPol was conducted to evaluate its suitability for industrial applications. The PUR foam formulation was designed based on the hydroxyl number of the BioPol, as determined by ASTM D4274. BioPol was combined with a commercial trifunctional polyol derived from the oxypropylation of glycerol, enabling the entire polyol component of the formulation to be classified as bio-based. Increasing the BioPol content in the formulation enhanced the cross-linking density of the resulting foams, which also led to a reduction in the average pore diameter. Uniaxial compressive strength tests revealed superior mechanical properties, with maximum resistance recorded at 3.18 MPa compared with the blank sample. The resultant high-density rigid PUR foams exhibit excellent thermal stability, mechanical robustness, and ease of processability, establishing a promising pathway for developing durable and eco-friendly bio-based polyurethane products.

In the current study plaster − expanded perlite microsphere composites, were investigated regarding their thermal insulation properties. In this context commercially available plaster powder was mixed with expanded perlite microspheres, of various grain size distribution and bulk density, aiming the investigation of the effect of ultrafines in the aggregates on the mechanical properties of the composites. The mixing procedure resembles that of making plaster mortars, in building construction. Thermal conductivity of composites was found to be sizably lower than that of pure plaster, and was further decreased with increasing filler loading. Moreover, filler density seems to affect thermal insulation performance, at high loading concentrations. Slight increase of the mechanical properties was identified when aggregates include ultrafine particles. Thermal insulation performance experiments indicate that plaster − expanded perlite microsphere composites clearly exhibit better thermal insulation properties, in comparison to pure plaster. Overall, expanded plaster − expanded perlite microsphere composites seem to be efficient insulation materials for potential applications in buildings’ construction, toward reducing their energy footprint.

The suppression of wave-particle duality in multiple-slit experiments indicated the presence of type I diffracted photons with particle behavior. Overcoming the diffraction limit is possible with type I diffracted photons and will be applied in optical lithography. In this paper, we present results on a diffraction-free optical lithography, projection quantum optical lithography (projection QOL), with different NA projection lenses and ${\sim}{14}\;{\rm nm}$ resolution. A potential application for realizing complex 1 nm patterns is analyzed. Projection QOL could support the research and development efforts of the semiconductor chip industry.

Highlights What are the main findings? A novel chemiresistive sensor utilizing (carbon nano-onions) CNOs and (polyvinyl alcohol) PVA sensing layers demonstrates effective relative humidity (RH) detection. The sensitivity is highly reproducible across multiple sensors for the sensor made with CNOs–PVA (1:1, w/w) sensing layers. What is the implication of the main finding? The developed RH sensor architecture is both sustainable and metal-free, employing nanocarbon materials. It offers distinct sensitivity across two humidity domains, making it a promising solution for eco-friendly and precise humidity sensing applications. Abstract This paper reports several preliminary investigations concerning the relative humidity (RH) detection response of a chemiresistive sensor that uses a novel sensing layer based on pristine carbon nano-onions (CNOs) and polyvinyl alcohol (PVA) at a 1/1 and 2/1 w/w ratio. The sensing device, including a Si/SiO2 substrate and gold electrodes, is obtained by depositing the CNOs–PVA aqueous suspension on the sensing structure by drop casting. The composition and morphology of the sensing film are explored by means of scanning electron microscopy, Raman spectroscopy, atomic force microscopy, and X-ray diffraction. The manufactured sensor’s room temperature RH detection performance is examined by applying a continuous flow of the electric current between the interdigitated electrodes and measuring the voltage as the RH varies from 5% to 95%. For RH below 82% (sensing layer based on CNOs–PVA at 1/1 w/w ratio) or below 50.5% (sensing layer based on CNOs–PVA at 2/1 w/w ratio), the resistance varies linearly with RH, with a moderate slope. The newly developed sensor, using CNOs–PVA at a 1:1 ratio (w/w), responded as well as or better than the reference sensor. At the same time, the recorded recovery time was about 30 s, which is half the recovery time of the reference sensor. Additionally, the changes in resistance (ΔR/ΔRH) for different humidity levels showed that the CNOs–PVA layer at 1:1 was more sensitive at humidity levels above 80%. The main RH sensing mechanisms considered and discussed are the decrease in the hole concentration in the CNOs during the interaction with an electron donor molecule, such as water, and the swelling of the hydrophilic PVA. The experimental RH detection data are analyzed and compared with the RH sensing results reported in previously published work on RH detectors employing sensing layers based on oxidized carbon nanohorns–polyvinylpirrolidone (PVP), oxidized carbon nanohorns–PVA and CNOs–polyvinylpyrrolidone.

In recent years, field-effect transistors (FETs) based on graphene have attracted significant interest due to their unique electrical properties and their potential for biosensing and molecular detection applications. This study uses FETs with a nanocrystalline graphite (NCG) channel to detect DNA nucleobases. The exceptional electronic properties of NCG, and its high surface area, enable strong π–π stacking interactions with DNA nucleobases, promoting efficient adsorption and stabilization of the biomolecules. The direct attachment of nucleobases to the NCG channel leads to substantial changes in the device’s electrical characteristics, which can be measured in real time to assess DNA binding and sequence recognition. This method enables highly sensitive, label-free DNA detection, opening up new possibilities for rapid genetic analysis and diagnostics. Understanding the interactions between DNA nucleobases and graphene-based materials is crucial for advancing genetic research and biotechnology, paving the way for more accurate and efficient diagnostic tools.

Thyroid Cancer (TC) is one of the most prevalent endocrine malignancies, with early detection being critical for patient management. The motivation for integrating Machine Learning (ML) in thyroid cancer research stems from the limitations of conventional diagnostic and monitoring approaches, as ML offers transformative potential for reducing human errors and improving prediction outcomes for diagnostic accuracy, risk stratification, treatment options, recurrence prognosis, and patient quality of life. This scoping review maps existing literature on ML applications in TC, particularly those leveraging clinical data, Electronic Medical Records (EMRs), and synthesized findings. This study analyzed 1231 papers, evaluated 203 full-text articles, selected 21 articles, and detailed three themes: (1) malignancy prediction and nodule classification; (2) other metastases derived from TC prediction; and (3) recurrence and survival prediction. This work examined the case studies’ characteristics and objectives and identified key trends and challenges in ML-driven TC research. Finally, this scoping review addressed the limitations of related and highlighted directions to enhance the clinical potential of ML in this domain while emphasizing its capability to transform TC patient care into advanced precision medicine.

Dimethylsulfoxide (DMSO) is widely used as a solvent or as a carrier when screening for biologic activity of various chemicals, but results need to be interpreted carefully due to its intrinsic toxicity. DMSO has been previously observed to impair the growth of yeast cells defective in calcium movement across cellular membranes and in phosphoinositol pyrophosphate synthases. Here, we set out to investigate the Ca²⁺‐mediated response to DMSO in Saccharomyces cerevisiae. The cell exposure to DMSO was signaled by a two‐phase cytosolic Ca²⁺ wave that was dependent on Mid1, a subunit of the Cch1/Mid1 Ca²⁺ channel located at the plasma membrane. While the vacuolar Ca²⁺ channel Trpy1 also contributed by releasing Ca²⁺ from the vacuole, the immediate cell response to DMSO exposure depended on the external Ca²⁺ imported into the cell through Cch1/Mid1. A chemogenomic screen previously performed on a collection of yeast knockout mutants identified the two phosphoinositol pyrophosphate synthases Kcs1 and Vip1 as determinants for yeast tolerance to DMSO. Deletion of KCS1 or VIP1 genes suppressed the DMSO‐induced Ca²⁺ response, suggesting that both Ca²⁺ and phosphoinositol pyrophosphate signaling contribute to cell adaptation under DMSO stress.

We present here a comprehensive review of various classes of electric-field-induced reversible Mott metal-insulator materials, which have many applications in ultrafast switches, reconfigurable high-frequency devices up to THz, and photonics. Various types of Mott transistors are analyzed, and their applications are discussed. This paper introduces new materials that demonstrate the Mott transition at very low DC voltage levels, induced by an external electric field. The final section of the paper examines ferroelectric Mott transistors and these innovative ferroelectric Mott materials.

This paper proposes a detailed design study of resonating high-frequency notch filters driven by RF MEMS switches and their optimization for dual-band operation in the X-Band. Microstrip configurations will be considered for single and dual-band applications. An SPDT (single-pole-double-thru) switch composed of double-clamped ohmic microswitches has been introduced to connect triangular resonators with Sierpinski geometry, symmetrically placed with respect to a microstrip line to obtain a dual notch response. Close frequencies or spans as wide as 2 GHz can be obtained depending on the internal complexity and the edge side. The internal complexity has been modified to introduce the possibility of using the same edge size for the frequency tuning of an elementary cell, maintaining a fixed footprint, and allowing coupled structures to implement high-frequency filters of the same size and variable operational frequencies. Preliminary experimental results have been obtained as a confirmation of the predicted device functionality.

Background/Objectives: Malnutrition is a key determinant of quality of life (QoL) in patients with head and neck cancers (HNCs), influencing treatment outcomes and the occurrence of adverse events (AEs). Despite there being numerous studies on nutritional status and QoL, there is no standardized risk or prognostic model integrating clinical and demographic factors. Methods: A literature search was conducted in September 2024 in Scopus, PubMed, and Web of Science, covering studies published between 2013 and 2024. Articles were selected based on their relevance to AEs, nutritional interventions, and QoL assessments in HNC patients. Results: The key factors influencing QoL in HNC patients include age, sex, weight, BMI, educational level, and tumor features. Mucositis was identified as the most significant food intake-impairing AE, contributing to malnutrition and reduced QoL. Current QoL assessments rely on descriptive questionnaires, which lack personalization and predictive capabilities. Digital tools, including machine learning models and digital twins, offer potential solutions for risk prediction and personalized nutritional interventions. Conclusions: Despite significant research efforts, QoL assessment in HNC patients remains non-uniform, and risk models integrating nutritional status are lacking. A comprehensive, personalized approach is needed, leveraging digital tools to improve nutritional intervention strategies.

Background/Objectives: Cancer remains one of the leading causes of mortality worldwide. Despite significant advancements in treatment strategies and drug development, survival rates remain low and the adverse effects of conventional therapies severely impact patients’ quality of life. This study evaluates the therapeutic potential of plant-derived extracts in hepatocellular carcinoma treatment, with a focus on minimizing side effects while enhancing efficacy. Methods: This research investigates the in vitro synergistic effect of silver bio-nanoparticles synthesized from Clematis vitalba, Melissa officinalis, and Taraxacum officinale extracts (Clematis vitalbae extractum—CVE, Melissae extractum—ME, Taraxaci extractum—TE) in combination with liver cancer drugs, sunitinib (SNTB) and imatinib (IMTB), on HepG2 (human hepatocellular carcinoma) and HUVEC (human umbilical vein endothelial) cell lines. The silver nanoparticles (AgNPs) were characterized using UV-Vis spectroscopy, dynamic light scattering (DLS), zeta potential analysis, and scanning electron microscopy (SEM). The antitumor effects were evaluated through cell viability assays after 24 and 48 h of exposure, with additional cytotoxicity tests on HUVEC cells. Results: Results indicated that Melissa officinalis-derived silver nanoparticles (ME AgNPs) and Clematis vitalba extract with silver nanoparticles (CVE AgNPs) significantly reduced HepG2 cell viability. Their efficacy improved when combined with conventional therapies (SNTB + ME AgNPs 1:1 vs. SNTB: 20.01% vs. 25.73%, p = 0.002; IMTB + ME AgNPs 1:1 vs. IMTB: 17.80% vs. 18.08%, p = 0.036; SNTB + CVE AgNPs 1:1 vs. SNTB: 18.73% vs. 25.73%, p = 0.000; SNTB + CVE AgNPs 1:2 vs. SNTB: 26.62% vs. 41.00%, p = 0.018; IMTB + CVE AgNPs 1:1 vs. IMTB: 12.99% vs. 18.08%, p = 0.001). Taraxacum extract exhibited similar cytotoxicity to its nanoparticle formulation but did not exceed the efficacy of the extract alone at 24 h. Selectivity index assessments confirmed that AgNPs-based formulations significantly improve cytotoxicity and selectivity to HepG2 cells. Among the tested extracts, CVE demonstrated the strongest antitumor effect, enhancing the efficacy of synthetic drugs (CI < 1). SNTB + TE AgNPs (5% EtOH) also demonstrated consistent synergy at high doses, while SNTB + CVE AgNPs provided broad-range synergy, making it suitable for dose-escalation strategies. Conclusions: These findings underscore the potential of nanoparticle-based formulations in combination therapies with targeted kinase inhibitors such as sunitinib and imatinib. Future research should focus on in vivo validation and clinical trials to confirm these findings.

A single field-effect transistor (FET) based on nitrogen doped-nickel oxide (NiON) semiconductor ferroelectric shows an ultralow voltage switch at a gate voltage value of just 1 μV and a subthreshold swing (SS) of 55 mV/decade. The same FET acts as a ferroelectric capacitive non-volatile memory between the drain and the ground. All these features are retrieved in a FET based on NiON grown on a thin layer of aluminum oxide (Al2O3), which was deposited on a doped silicon (Si) wafer. After 1 year, we retrieved the same values in our devices without any thermal annealing or other procedures to wake up the ferroelectricity.

The study presents the ethanol vapor sensing performance of a resistive sensor that utilizes a quaternary nanohybrid sensing layer composed of holey carbon nanohorns (CNHox), graphene oxide (GO), SnO2, and polyvinylpyrrolidone (PVP) in an equal mass ratio of 1:1:1:1 (w/w/w/w). The sensing device includes a flexible polyimide substrate and interdigital transducer (IDT)-like electrodes. The sensing film is deposited by drop-casting on the sensing structure. The morphology and composition of the sensitive film are analyzed using scanning electron microscopy (SEM), Energy Dispersive X-ray (EDX) Spectroscopy, and Raman spectroscopy. The manufactured resistive device presents good sensitivity to concentrations of alcohol vapors varying in the range of 0.008–0.16 mg/cm³. The resistance of the proposed sensing structure increases over the entire range of measured ethanol concentration. Different types of sensing mechanisms are recognized. The decrease in the hole concentration in CNHox, GO, and CNHox due to the interaction with ethanol vapors, which act as electron donors, and the swelling of the PVP are plausible and seem to be the prevalent sensing pathway. The hard–soft acid-base (HSAB) principle strengthens our analysis.

The present work regards a unique yet study of 3D structured surface evolution of nano-balls and walls-like features with thickness variation, for tungsten oxide (WO3) thin films made by spray deposition. Since in most optoelectronic applications the surface morphology and structure play a crucial role and WO3 is one of the most studied and used metal oxide semiconductors in a significant variety of optoelectronic applications, a detailed study of recently observed and reported unique 3D complex architecture of WO3 coatings fabricated by spray pyrolysis (starting from different precursors) is of great importance for further development of thin film coatings and devices. In this scope, two different series of WO3 of 11 samples with different thicknesses each, starting from two tungsten peroxide precursor concentrations (0.05 M and 0.1 M) were fabricated by spray pyrolysis and thoroughly characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction and Raman spectroscopy. Results suggest that, for the mentioned concentrations, the main structural differences affect mostly the surface morphology and slightly the surface texturing. These observations prove the reliability of fabrication of coatings with such surface morphology by spray pyrolysis method and open new perspectives for better sensors, electrochromic or photochromic devices, and more.

This paper presents the simulation and experimental results for high-frequency surface acoustic wave (SAW) sensors for humidity detection. The SAW structures with a wavelength of 680 nm are fabricated on GaN/SiC and presented two resonance frequencies: ~6.66 GHz for the Rayleigh propagation mode and ~8 GHz for the Sezawa mode. A SiO2 thin layer (~50 nm thick) was employed for the functionalization of the SAW. Relative humidity characterization was performed in the range of 20–90%. The SAW sensors achieved high values of humidity sensitivity for both adsorption and desorption. The Sezawa mode showed about 2.5 times higher humidity sensitivity than the Rayleigh mode: 17.2 KHz/%RH versus 6.17 KHz/%RH for adsorption and 8.88 KHz/%RH versus 3.79 KHz/%RH for desorption.

Graphene/CNT layers were deposited onto platinum electrodes of an interdigitated sensor using radio-frequency magnetron sputtering. The graphene/CNTs were synthesized in an Argon atmosphere at a pressure of (2 × 10⁻²–5 × 10⁻³) mbar, with the substrate maintained at 300 °C either through continuous heating with an electronically controlled heater or by applying a −200 V bias using a direct current power supply throughout the deposition process. The study compares the surface morphology, carbon atom arrangement within the layer volumes, and electrical properties of the films as influenced by the different methods of substrate heating. X-ray diffraction and Raman spectroscopy confirmed the formation of CNTs within the graphene matrix. Additionally, scanning electron microscopy revealed that the carbon nanotubes are aligned and organized into cluster-like structure. The graphene/CNT layers produced at higher pressures present exponential I–V characteristics that ascertain the semiconducting character of the layers and their suitability for applications in gas sensing.

Hydrogels are a viable option for biomedical applications due to their biocompatibility, biodegradability, and ability to incorporate various healing agents while maintaining their biological efficacy. This study focused on the preparation and characterization of novel hybrid hydrogels enriched with the natural algae compound Ulvan for potential use in wound dressings. The characterization of the hydrogel membranes involved multiple methods to assess their structural, mechanical, and chemical properties, such as pH measurements, swelling, moisture content and uptake, gel fraction, hydrolytic degradation, protein adsorption and denaturation tests, rheological measurements, SEM, biocompatibility testing, and scratch wound assay. The hydrogel obtained with a higher concentration of Ulvan (1 mg/mL) exhibited superior mechanical properties, a swelling index of 264%, a water content of 55%, and a lower degradation percentage. In terms of rheological properties, the inclusion of ULV in the hydrogel composition enhanced gel strength, and the Alginate + PVA + 1.0ULV sample demonstrated the greatest resistance to deformation. All hydrogels exhibited good biocompatibility, with cell viability above 70% and no obvious morphological modifications. The addition of Ulvan potentiates the regenerative effect of hydrogel membranes. Subsequent studies will focus on encapsulating bioactive compounds, investigating their release behavior, and evaluating their active biological effects.

Introduction: Repeated COVID-19 booster vaccination was recommended in healthcare workers (HCWs) to maintain protection. We measured the relative vaccine effectiveness (rVE) of the second booster dose of COVID-19 vaccine compared to the first booster, against laboratory-confirmed SARS-CoV-2 infection in HCWs. Methods: In a prospective cohort study among HCWs from 12 European hospitals, we collected nasopharyngeal or saliva samples at enrolment and during weekly/fortnightly follow-up between October 2022 and May 2023. We estimated rVE of the second versus first COVID-19 vaccine booster dose against SARS-CoV-2 infection, overall, by time since second booster and restricted to the bivalent vaccines only. Using Cox regression, we calculated the rVE as (1-hazard ratio)*100, adjusting for hospital, age, sex, prior SARS-CoV-2 infection and at least one underlying condition. Results: Among the 979 included HCWs eligible for a second booster vaccination, 392 (40 %) received it and 192 (20 %) presented an infection during the study period. The rVE of the second versus first booster dose was −5 % (95 %CI: −46; 25) overall, 3 % (−46; 36) in the 7–89 days after receiving the second booster dose. The rVE was 11 % (−43; 45) when restricted to the use of bivalent vaccines only. Conclusion: The bivalent COVID-19 could have reduced the risk of SARS-CoV-2 infection among HCWs by 11 %. However, we note the limitation of imprecise rVE estimates due to the proportion of monovalent vaccine used in the study, the small sample size and the study being conducted during the predominant circulation of XBB.1.5 sub-lineage. COVID-19 vaccine effectiveness studies in HCWs can provide important evidence to inform the optimal timing and the use of updated COVID-19 vaccines.