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When teaching STEM courses, it is important to introduce state-of-the-art techniques. Students need to learn how to conduct experiments, analyse data and choose the most effective approaches to address meaningful situations. Here we present the assessment of the implementation of a structured inquiry-based activity aimed at teaching students about protein mass and size. This activity emerges as an intervention in our educational module, designed to create a cognitive conflict that effectively drives a conceptual change. To evaluate the efficacy of this module, we collected data on students' perceived and actual knowledge through pre- and post-class surveys (n = 36 and 34, respectively, mean age 26 ± 2). Additionally, we evaluated lab reports using a detailed rubric. Results indicate that the practical innovation we propose is a challenging activity that promotes the accomplishment of our learning objectives. The activity led to improvements both in confidence and in actual mastery of theoretical concepts and techniques. After completing the activity, students were able to choose the most appropriate technique to solve specific problems. Furthermore, we found that the use of a structured questionnaire in lab reports helped students to accurately analyse and process experimental data. It also allows them to demonstrate understanding of technical limitations, while integrating the knowledge and skills acquired during the module. Overall, this activity provides notions that are conceivable and profitable, thus leading to successful conceptual changes.

Regenerative hydrogels from natural polymers have come forth as auspicious materials for use in regenerative medicine, with interest attributed to their intrinsic biodegradability, biocompatibility, and ability to reassemble the extracellular matrix. This review covers the latest advances in regenerative hydrogels used for wound healing, focusing on their chemical composition, cross-linking mechanisms, and functional properties. Key carbohydrate polymers, including alginate, chitosan, hyaluronic acid, and polysaccharide gums, including agarose, carrageenan, and xanthan gum, are discussed in terms of their sources, chemical structures and specific properties suitable for regenerative applications. The review further explores the categorization of hydrogels based on ionic charge, response to physiological stimuli (i.e., pH, temperature) and particularized roles in wound tissue self-healing. Various methods of cross-linking used to enhance the mechanical and biological performance of these hydrogels are also examined. By highlighting recent innovations and ongoing challenges, this article intends to give a detailed understanding of natural hydrogels and their potential to revolutionize regenerative medicine and improve patient healing outcomes.

In search of new materials that would help to prevent microbiologically influenced corrosion (MIC), we have designed and synthetized six different copper and copper–silver nanoparticle–enzyme hybrids using a mild-conditions method carried out in water and r.t. Characterization analyses exhibited the presence of small crystalline nanoparticles with diameters from 2 to 20 nm. X-ray diffraction determined that the Cu hybrids were composed of different copper species, depending on the synthetic protocol used, while the Cu–Ag hybrids were mainly composed of copper and silver phosphate metallic species. Then, the bacterial viability of three MIC-relevant enrichments, sulfate-reducing bacteria (SRB), slime-forming bacteria (SFB), and acid-producing bacteria (APB), was studied in the presence of the bionanohybrids. The results demonstrated a notable effect of all bionanohybrids against SRB, one of the most prominent bacteria associated with MIC. In particular, Cu-2 and Cu–Ag-2 showed a reduction in bacterial cells of 94% and 98% after 48 h, respectively, at a concentration of 100 ppm. They also exhibited high efficiencies against SFB, with Cu–Ag-1 and Cu–Ag-2 hybrids being the best, with bacterial reduction percentages of 98% after 45 h of exposition at a concentration of 100 ppm. However, in the case of APB, the effect of the hybrids was lost due to the low pH level generated during the experiment. Finally, the capacity of Cu-2 and Cu–Ag-2 to inhibit the adhesion of SRB to the surface of carbon steel coupons was evaluated. Fluorescence imaging of the surface of the coupons at 24 h demonstrated that the presence of the hybrids inhibited the growth of SRB, obtaining a maximum reduction of 98% with Cu-2. Overall, the results of this study demonstrate that these novel nanomaterials have a wide-range antibacterial effect and may have a promising future in the prevention and treatment of MIC.

Bimetallic nanomaterials have generated significant interest across diverse scientific disciplines, due to their unique and tunable properties arising from the synergistic combination of two distinct metallic elements. This study presents a novel approach for synthesizing branched gold–platinum nanoparticles by utilizing poly(allylamine hydrochloride) (PAH)-stabilized branched gold nanoparticles, with a localized surface plasmon resonance (LSPR) response of around 1000 nm, as a template for platinum deposition. This approach allows precise control over nanoparticle size, the LSPR band, and the branching degree at an ambient temperature, without the need for high temperatures or organic solvents. The resulting AuPt branched nanoparticles not only demonstrate optical activity but also enhanced catalytic properties. To evaluate their catalytic potential, we compared the enzymatic capabilities of gold and gold–platinum nanoparticles by examining their peroxidase-like activity in the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). Our findings revealed that the incorporation of platinum onto the gold surface substantially enhanced the catalytic efficiency, highlighting the potential of these bimetallic nanoparticles in catalytic applications.

This study explores the stability of biomechanical parameters of the running stride of male trained athletes during a half-marathon competition. Using a field-based descriptive design, eight male athletes from a local training group were monitored throughout an official half-marathon race under identical conditions, assessing biomechanical parameters including ground contact time (GCT), leg spring stiffness (LSS), vertical oscillation (VO), and stride length (SL) recorded via the Stryd Summit Power Meter. A repeated measures analysis of variance (RM ANOVA) was conducted to detect significant changes in biomechanical parameters as the race progressed. Results demonstrated minimal changes in all parameters, with no significant differences observed for GCT (F = 0.96, p = 0.38), VO (F = 0.23, p = 0.87), and SL (F = 1.07, p = 0.35), and a small (η2 = 0.004) yet statistically significant difference in LSS (F = 5.52, p = 0.03) between the first and second segments, indicating that athletes were able to maintain stable biomechanical parameters throughout the race. The conclusion highlights the need for personalized training programs tailored to the unique biomechanical adaptations and demands of endurance running.

Environmental forensics is the application of knowledge from geosciences and chemistry in a legal setting, e.g., to determine the origin and consequences of contamination events. Teaching environmental forensics requires reactivating prior knowledge from different fields of natural sciences, filling knowledge gaps, and connecting pieces of scientific evidence to form logical chains of arguments. Here, we present a cooperative teaching format that successfully covers the challenges of interdisciplinary teaching while further developing learners' soft skills. Through role-playing in a mock trial of a famous hexavalent chromium [Cr(VI)] contamination case in California, learners choose to team with the town of Hinkley, as the plaintiff team, or with Pacific Gas & Electric (PG&E), the company accused of the contamination, as the defense team. After introductory sessions, the teams summarize facts, and build and present arguments to support their claims regarding the formation of the Cr(VI) plume, the impact on the population's health, and remediation efforts taken by PG&E. These arguments are delivered in front of their peers and instructors, acting as judges, in a mock trial. Here, we summarize different modalities that have been tested over the past 10 years regarding role assignment and team building. This teaching format has been shown to be successful in engaging learners with the scientific aspects of the case-based trial while helping them become critical about information they are confronted with, delivering arguments in structured ways, defending their points of view, and improving communication skills on a peer- and layperson-level.

Abstract Two-dimensional materials present exceptional crystal elasticity and provide an ideal platform to tune electrical and optical properties through the application of strain. Here we extend recent research on strain engineering in monolayer molybdenum disulfide using an adamantane plasma polymer pinning layer to achieve unprecedented crystal strains of 2.8%. Using micro-reflectance spectroscopy, we report maximum strain gauge factors of −99.5 meV/% and −63.5 meV/% for the A and B exciton of monolayer MoS2, respectively, with a 50 nm adamantane capping layer. These results are corroborated with photoluminescence and Raman measurements on the same samples. Taken together, our results indicate that adamantane polymer is an exceptional capping layer to transfer substrate-induced strain to a 2D layer and achieve higher levels of crystal strain.

Condition-based maintenance of a machine tool spindle unit is known to reduce the total cost of operation in a manufacturing environment. However, standard vibration monitoring thresholds, which are based only on average vibration energy levels, do not account for the machine’s dynamics, such as dynamic stiffness and damping ratios, which, ultimately, control the final quality of a machined workpiece. In this study, a new mechanical device is proposed for the estimation of spindle dynamics characteristics through measurement of the frequency response function (FRF) of the spindle. The device is simple, robust in a manufacturing environment, small, and requires no power source. The new device is shown to be comparable in performance to conventional impact hammer testing, with the advantage of being fully automated and capable of dynamic assessment on a rotating spindle. Such a device allows a machine tool operator to routinely monitor the stiffness and damping ratios of the spindle unit and make informed maintenance decisions based on meaningful changes in operating conditions that impact production.

Background: We propose a three-dimensional path-planning method to generate optimized surgical trajectories for steering flexible needles along curved paths while avoiding critical tracts in the context of surgical glioma resection. Methods: Our approach is based on an application of the rapidly exploring random tree algorithm for multi-trajectory generation and optimization, with a cost function that evaluates different entry points and uses the information of MRI images as segmented binary maps to compute a safety trajectory. As a novelty, an avoidance module of the critical neuronal tracts defined by the neurosurgeon is included in the optimization process. The proposed strategy was simulated in real-case 3D environments to reach a glioma and bypass the tracts of the forceps minor from the corpus callosum. Results: A formalism is presented that allows for the evaluation of different entry points and trajectories and the avoidance of selected critical tracts for the definition of new neurosurgical approaches. This methodology can be used for different clinical cases, allowing the constraints to be extended to the trajectory generator. We present a clinical case of glioma at the base of the skull and access it from the upper area while avoiding the minor forceps tracts. Conclusions: This path-planning method offers alternative curved paths with which to reach targets using flexible tools. The method potentially leads to safer paths, as it permits the definition of groups of critical tracts to be avoided and the use of segmented binary maps from the MRI images to generate new surgical approaches.

The growing interest in “Traineras”, a traditional competitive rowing modality prevalent in Northern Spain, underscores the need for a comprehensive analysis of the injury incidence associated with this sporting practice. Despite rowing’s significance in the international sports arena and its inclusion since the beginnings of the modern Olympic Games, research into injuries in this sport, especially in traditional modalities such as Traineras, has been limited. This study aimed to identify and describe the predominant injuries among Traineras rowers, analyzing their epidemiology, characteristics, affected body regions, and diagnoses, further differentiated by competitive level and gender. A retrospective survey completed by 773 rowers (24% women, 76% men) participating in various leagues (ACT, ARC1, ARC2, LGT1, LGT2, ETE, and LGT-F) during the season revealed that 68.2% suffered from at least one injury, predominantly due to overuse (91.1% in men, 83.1% in women). The most affected regions were the lower back and shoulders, with the main diagnoses being muscle cramps and tendinitis, showing statistically significant differences between sexes. The findings of this study not only provide a deeper understanding of the etiology and origin of injuries in this sport but also lay the groundwork for developing specific injury prevention plans, thereby contributing to the safety and optimal performance of athletes.

Highway bridges are crucial civil constructions for the transport infrastructure, which require proper attention from the corresponding institutions of each country and constant financing for their adequate maintenance; this is important because different types of damage can be generated within these structures, caused by natural disasters, among other sources, and the heavy loads they transport every day. Therefore, the development of simple, efficient, and low-cost methods is of vital importance, allowing us to identify damage in a timely manner and avoid bridges collapsing. As reported in a previous work, the wavelet energy accumulation method (WEAM) and its corresponding application in the Rio Papaloapan Bridge (RPB) represented an important advance within the field. Despite identifying damage in bridges with precision and at a low cost, there are several aspects to improve in that method. Therefore, in this work, that method was improved, eliminating several steps, and meaningfully reducing the computational burden by implementing an algorithm based on the Shannon entropy, thus giving way to the new entropy wavelet-based method (EWM). This new method was applied directly with regard to the real-life RPB, in both its healthy and damaged conditions. Also, its corresponding numerical model based on the finite element method in its healthy condition and different damage scenarios were carried out. The results indicate that the new EWM retains the advantages of WEAM, and it allows for damage identification to be completed more efficiently, increasing the precision by approximately 0.11%, and significantly reducing the computing time required to obtain results by 5.67 times.

Maintenance of the linear axis and its components such as the linear guide can be significantly costly due to the difficult nature of the repair procedure and the downtime the machine exhibits while being repaired. This is a decision that must be made carefully and with proper justification. Therefore, it is crucial that the condition-based monitoring (CBM) system in the machine can detect and localize faults in the linear axis. The presented paper proposes a novel vibration signal segmentation analysis technique that detects and localizes misalignment in the linear guide rail, which is considered a leading root-cause failure fault. The results demonstrated that the usability of time domain features such as RMS was doubled by applying segmentation analysis. Also, evaluating both stroke directions aided in the localization of the misalignment. Overall, the practical value of the proposed technique is to function as both a localization and repair verification tool when performing linear axis maintenance.

Summary: The combination of structural characterization at atomic resolution, chemical data, and theoretical insights has revealed the unique nanostructures which develop in ceria supported on yttria-stabilized zirconia (YSZ) after being submitted to high-temperature reducing treatments. The results show that just a small ceria loading is needed for creating a supported Zr-rich pyrochlore (111) nanostructure, resembling the structure of single cerium atom catalysts. The specific atomic arrangement of this nanostructure allows to explain the improvement of the reducibility at low temperature. The reduction mechanism can be extrapolated to ceria-zirconia mixed oxides with pyrochlore-like cationic ordering, exposing Zr-rich (111) surfaces. The results gathered here provide key information to understand the redox behavior of these types of systems, which may contribute to improving the design of new ceria-zirconia based materials, with lower content of the lanthanide element, nearly 100% cerium atom utilization, and applications in environmental catalysis.

Bioactives are functional molecules that pose several challenges, including poor solubility, low permeability, and low chemical, biochemical, or process stability, resulting in reduced functionality and bioavailability [...]

Cu-Al-Ni is a high-temperature shape memory alloy (HTSMA) with exceptional thermomechanical properties, making it an ideal active material for engineering new technologies able to operate at temperatures up to 200 °C. Recent studies revealed that these alloys exhibit a robust superelastic behavior at the nanometer scale, making them excellent candidates for developing a new generation of micro-/nano-electromechanical systems (MEMS/NEMS). The very large-scale integration (VLSI) technologies used in microelectronics are based on thin films. In the present work, 1 μm thickness thin films of 84.1Cu-12.4 Al-3.5Ni (wt.%) were obtained by solid-state diffusion from a multilayer system deposited on SiNx (200 nm)/Si substrates by e-beam evaporation. With the aim of evaluating the thermal stability of such HTSMA thin films, heating experiments were performed in situ inside the transmission electron microscope to identify the temperature at which the material was decomposed by precipitation. Their microstructure, compositional analysis, and phase identification were characterized by scanning and transmission electron microscopy equipped with energy dispersive X-ray spectrometers. The nucleation and growth of two stable phases, Cu-Al-rich alpha phase and Ni-Al-rich intermetallic, were identified during in situ heating TEM experiments between 280 and 450 °C. These findings show that the used production method produces an HTSMA with high thermal stability and paves the road for developing high-temperature MEMS/NEMS using shape memory and superelastic technologies.

The periodic table is an essential topic in the teaching and learning of science at all education levels, as it contains information about the main physical and chemical properties of the different elements constituting the matter. However, becoming familiar with the facts behind the periodic table such as the element names and/or symbols, their metallic character, their electronegativity, and so on, may seem a tedious and boring task, depending on the approach the teacher uses. One way to stimulate students is through so-called gamification, in which learning occurs as an "almost undetected" consequence of playing a game. Of course, the game must be designed and prepared in such a way that the game and learning come together. In this work, we present Chemical Battleship, a chemical version of the classic board game Battleship, to learn the main topics contained in the periodic table and identify the common glassware of the lab. Additionally, using this game facilitates presenting the chemistry from a fun approach to certain educational levels. The periodic table itself is used to deploy the "fleet", which is actually just labware. The "shots" must be "fired" by identifying the chemical element the player wants to fire at, and they must do so by using different properties of the element. Repeating this process, students get soon familiar with the periodic table and the information it contains, as well as with the lab glassware. Chemical Battleship was tested with elementary school students and third-year students in a Primary Education Teacher Degree program. Use of this game had a high acceptance from both groups, awakening students' interest and curiosity in the first group and improving knowledge in the latter group. Students enhanced not only their subjective perception of their knowledge but also what they really know about the periodic table, as reflected in the improvement of their marks.

Gold nanoparticles (AuNPs) are essential metal nanoparticles, and they have much application in different areas such as bio-imaging, medical therapy, enzyme assays and the environment. Various physical and chemical methods have been used for the synthesis of AuNPs. However the disadvantage of most of them is to generate a large number of by-products that are dangerous, in this sense, green synthesis with plant extracts has become one of the preferred methods for the development of these materials because it produces particles with high bioavailability and reduces the use of toxic chemicals. In addition to presenting unique characteristics of biocompatibility, large surface area, and high dispersion, they have been used to treat different types of cancer, such as colon cancer. This review presents the various methods for synthesizing gold nanoparticles and their application in cancer therapy, focusing on the green synthesis of gold nanoparticles and their specific colon cancer application.

Present worldwide difficulties in healthcare and the environment have motivated the investigation and research of novel materials in an effort to find novel techniques to address the current challenges and requirements. In particular, the use of nanomaterials has demonstrated a significant promise in the fight against bacterial infections and the problem of antibiotic resistance. Metal nanoparticles and carbon-based nanomaterials in particular have been highlighted for their exceptional abilities to inhibit many types of bacteria and pathogens. In order for these materials to be as effective as possible, synthetic techniques are crucial. Therefore, in this review article, we highlight some recent developments in the design and synthesis of various nanomaterials, including metal nanoparticles (e.g., Ag, Zn, or Cu), metal hybrid nanomaterials, and the synthesis of multi-metallic hybrid nanostructured materials. Following that, examples of these materials’ applications in antimicrobial performance targeted at eradicating multi-drug resistant bacteria, material protection such as microbiologically influenced corrosion (MIC), or additives in construction materials have been described.

Chitosan-based hydrogels have gained significant attention for their potential applications in water treatment and purification due to their remarkable properties such as bioavailability, biocompatibility, biodegradability, environmental friendliness, high pollutants adsorption capacity, and water adsorption capacity. This article comprehensively reviews recent advances in chitosan-based hydrogel materials for water purification applications. The synthesis methods, structural properties, and water purification performance of chitosan-based hydrogels are critically analyzed. The incorporation of various nanomaterials into chitosan-based hydrogels, such as nanoparticles, graphene, and metal-organic frameworks, has been explored to enhance their performance. The mechanisms of water purification, including adsorption, filtration, and antimicrobial activity, are also discussed in detail. The potential of chitosan-based hydrogels for the removal of pollutants, such as heavy metals, organic contaminants, and microorganisms, from water sources is highlighted. Moreover, the challenges and future perspectives of chitosan-based hydrogels in water treatment and water purification applications are also illustrated. Overall, this article provides valuable insights into the current state of the art regarding chitosan-based hydrogels for water purification applications and highlights their potential for addressing global water pollution challenges.

The quantitative effect of seasonality on the prevalence of infectious diseases has been widely studied in epidemiological models. However, its influence in clinical prediction models has not been analyzed in great depth. In this work, we study the different approaches that can be employed to deal with seasonality when using white-box models related to infections, including two new proposals based on sliding windows and ensembles. We additionally consider the effects of class imbalance and high dimensionality, as they are common problems that must be confronted when building clinical prediction models. These approaches were tested with four datasets: two created synthetically and two extracted from the MIMIC-III database. Our proposed methods obtained the best results in the majority of the experiments, although traditional approaches attained good results in certain cases. On the whole, our results corroborate the theory that clinical prediction models for infections can be improved by considering the effect of seasonality, although the techniques employed to obtain the best results are highly dependent on both the dataset and the modeling technique considered.

The performance of male soccer players (MSPs) depends on multiple factors, such as body composition. It is understandable to think that, due to the physical demands and specific functions during play, body composition may vary depending on the playing position. The aim of this systematic review and meta-analysis was to describe the anthropometric, BC, and somatotype characteristics of professional MSPs and to compare the reported values according to playing position. We systematically searched Embase, PubMed, SPORTDiscus, and Web of Science following the PRISMA statement. Random-effects meta-analysis, a pooled summary of means, and 95% CI (method or equation) were calculated. Random models were used with the Restricted Maximum Likelihood (REML) method. Twenty-six articles were included in the systematic review and the meta-analysis. After comparing the groups according to the playing position (goalkeeper, defender, midfielder, and forward), significant differences were found in age, height, weight, the sum of skinfolds, kilograms of muscle mass, and kilograms of fat-free mass (p = 0.001; p < 0.0001). No significant differences were observed in fat mass, percentage of fat-free mass, percentage of muscle mass, bone mass, and somatotype. Despite the limitations, this study provides useful information to help medical–technical staff to properly assess the BC of professional MSPs, providing reference values for the different positions.

The aim of this study was to evaluate if the inertial measurement unit (IMU) Vmaxpro is a valid device to estimate vertical jump height (VJH) when compared to a motion capture system (MoCAP). Thirteen highly trained female volleyball players participated in this study which consisted of three sessions. After a familiarization session, two sessions comprised a warm-up followed by ten countermovement jumps, resting two min between each attempt. Jump height was measured simultaneously by Vmaxpro using take-off velocity and MoCAP using center-of-mass vertical excursion. Results show significant differences in jump height between devices (10.52 cm; p < 0.001; ES = 0.9), a very strong Spearman’s correlation (rs = 0.84: p < 0.001), and a weak concordance correlation coefficient (CCC = 0.22; ρ = 0.861; Cb = 0.26). Regression analysis reveals very high correlations, high systematic error (8.46 cm), and a nonproportional random error (SEE = 1.67 cm). Bland–Altman plots show systematic error (10.6 cm) with 97.3 % of the data being within the LoA. In conclusion, Vmaxpro can be considered a valid device for the estimation of VJH, being a cheaper, portable, and manageable alternative to MoCAP. However, the magnitude of systematic error discourages its use where indistinguishable data from Vmaxpro and MoCAP are used unless the corresponding specific fitting equation is applied.

The way we communicate has been revolutionised by the widespread use of social networks. Any kind of online message can reach anyone in the world almost instantly. The speed with which information spreads is undoubtedly the strength of social networks, but at the same time, any user of these platforms can see how toxic messages spread in parallel with likes, comments and ratings about any person or entity. In such cases, the victim feels even more helpless and defenceless as a result of the rapid spread. For this reason, we have implemented an automatic detector of toxic messages on social media. This allows us to stop toxicity in its tracks and protect victims. In particular, the aim of the survey is to demonstrate how traditional Machine Learning methods of Natural Language Processing (NLP) work on equal terms with Deep Learning methods represented by a Transformer architecture and characterised by a higher computational cost. In particular, the paper describes the results obtained by testing different supervised Machine Learning classifiers (Logistic Regression, Random Forest and Support Vector Machine) combined with two topic-modelling techniques of NLP, (Latent Semantic Analysis and Latent Dirichlet Allocation). A pre-trained Transformer named BERTweet was also tested. All models performed well in this task, so much so that values close to or above 90% were achieved in terms of the F1 score evaluation metric. The best result achieved by Transformer BERTweet, 91.40%, was therefore not impressive in this context, as the performance gains are too small compared to the computational overhead.

In this research, bio-based electrospun multilayered films for food packaging applications with good barrier properties and close to superhydrophobic behavior were developed. For this purpose, two different biopolymers, a low-melting point and fully bio-based synthetic aliphatic copolyamide 1010/1014 (PA1010/1014) and the microbially synthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and food-contact-complying organomodified silica (SiO2) nanostructured microparticles, were processed by electrospinning. The production of the multilayer structure was finally obtained by means of a thermal post-treatment, with the aim to laminate all of the components by virtue of the so-called interfiber coalescence process. The so developed fully electrospun films were characterized according to their morphology, their permeance to water vapor and oxygen, the mechanical properties, and their water contact angle properties. Interestingly, the annealed electrospun copolyamide did not show the expected improved barrier behavior as a monolayer. However, when it was built into a multilayer form, the whole assembly exhibited a good barrier, an improved mechanical performance compared to pure PHBV, an apparent water contact angle of ca. 146°, and a sliding angle of 8°. Consequently, these new biopolymer-based multilayer films could be a bio-based alternative to be potentially considered in more environmentally friendly food packaging strategies.

An accurate knowledge of the optical properties of β-Ga2O3 is key to developing the full potential of this oxide for photonics applications. In particular, the dependence of these properties on temperature is still being studied. Optical micro- and nanocavities are promising for a wide range of applications. They can be created within microwires and nanowires via distributed Bragg reflectors (DBR), i.e., periodic patterns of the refractive index in dielectric materials, acting as tunable mirrors. In this work, the effect of temperature on the anisotropic refractive index of β-Ga2O3 n(λ,T) was analyzed with ellipsometry in a bulk crystal, and temperature-dependent dispersion relations were obtained, with them being fitted to Sellmeier formalism in the visible range. Micro-photoluminescence (μ-PL) spectroscopy of microcavities that developed within Cr-doped β-Ga2O3 nanowires shows the characteristic thermal shift of red–infrared Fabry–Perot optical resonances when excited with different laser powers. The origin of this shift is mainly related to the variation in the temperature of the refractive index. A comparison of these two experimental results was performed by finite-difference time-domain (FDTD) simulations, considering the exact morphology of the wires and the temperature-dependent, anisotropic refractive index. The shifts caused by temperature variations observed by μ-PL are similar, though slightly larger than those obtained with FDTD when implementing the n(λ,T) obtained with ellipsometry. The thermo-optic coefficient was calculated.

The way that the new generations approach cultural contents changed dramatically. The audiovisual language substituted traditional media. Museums face now an important challenge to survive as cultural referents in this new paradigm: the introduction of new audiovisual languages in their exhibitions and the provision of attractive online content. The work presents a case study of the use of augmented reality and virtual reality (AR/VR) in a technological heritage museum, with a double approach: on the one hand the development of AR to enhance the real visit to the museum; and on the other, the provision of VR to ease online visits to the museum for those that do not want to or cannot visit it. The results show that young visitors massively appreciate the use of these technologies. Using AR contents also contributes to the preservation of the original artifacts without damage. Furthermore, multimedia content provides some contextual information, improving the learning experience. Regarding the VR application, it is thought as a complement to the AR experience. It was developed as a virtual reproduction of the museum visit that can be experienced from any location, thus contributing to a higher diffusion of the museum contents.

Lignocellulosic biomass dissolution in an inorganic salt hydrate (ZnCl2·4H2O) and its subsequent precipitation with water for the separation of its main compounds were investigated. For this purpose, different dissolution times and temperatures were studied, where 24 h and 70 °C were found to be the optimal choice. Three solids were obtained, which were analyzed and identified by XRD, SEM, NMR, and FTIR spectroscopy. Solid I is the undissolved part of the starting material, and it consists of lignin, which does not react with the inorganic salt hydrate and the unreacted cellulose. Solid II is a cellulose-rich solid with a low portion of hemicellulose and lignin, and Solid III is mainly pure lignin as the characterization results showed. Hemicellulose is mainly dissolved and hydrolyzed in the dissolution treatment and the amount present in all solids was very small. The reactivity of Solid I and Solid II in a hydrolysis reaction was tested (0.2 M/L H2SO4, 5 h, and 140 °C), where a significant improvement in the conversion and the yield of sugars was obtained with respect to the untreated samples in both cases. Solid II yields a large amount of total reducing sugars, with a % selectivity of 78–88%, depending on the starting biomass.

This study aimed to determine the criterion validity of the ADR jumping photocell when compared to a motion capture system and to examine the within-session test–retest reliability of the instrument. Thirteen highly trained female volleyball players performed ten countermovement jumps (CMJ) with two minutes rest in-between trials. Jumps were recorded simultaneously by both devices to compare the outcomes. The main results showed significant mean differences between devices (10.6 cm, p < 0.001; ES = 0.9), high Spearman’s correlations (ρ = 0.95), weak CCC (0.25), and SEE = 0.92 cm. Bland–Altman’s plot indicated high systematic errors (10.5 cm), heteroscedasticity of error (slope = 0.026), and all values included among the limits of agreement. The within-session reliability (internal consistency) was very high (ICC = 0.96; CCC = 0.94; SEM = 1.18 cm; CV = 4.21%). In addition, the sensitivity of the instrument showed values of SWC = 0.33 cm. In conclusion, ADR jumping is a valid instrument for the estimation of CMJ in highly trained female volleyball players. Furthermore, the instrument is shown to be a consistent tool in the measurement of CMJ.

Food quality is mainly affected by oxygen through oxidative reactions and the proliferation of microorganisms, generating changes in its taste, odor, and color. The work presented here describes the generation and further characterization of films with active oxygen scavenging properties made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) loaded with cerium oxide nanoparticles (CeO2NPs) obtained by electrospinning coupled to a subsequent annealing process, which could be used as coating or interlayer in a multilayer concept for food packaging applications. The aim of this work is to explore the capacities of these novel biopolymeric composites in terms of O2 scavenging capacity, as well as antioxidant, antimicrobial, barrier, thermal, and mechanical properties. To obtain such biopapers, different ratios of CeO2NPs were incorporated into a PHBV solution with hexadecyltrimethylammonium bromide (CTAB) as a surfactant. The produced films were analyzed in terms of antioxidant, thermal, antioxidant, antimicrobial, optical, morphological and barrier properties, and oxygen scavenging activity. According to the results, the nanofiller showed some reduction of the thermal stability of the biopolyester but exhibited antimicrobial and antioxidant properties. In terms of passive barrier properties, the CeO2NPs decreased the permeability to water vapor but increased the limonene and oxygen permeability of the biopolymer matrix slightly. Nevertheless, the oxygen scavenging activity of the nanocomposites showed significant results and improved further by incorporating the surfactant CTAB. The PHBV nanocomposite biopapers developed in this study appear as very interesting constituents for the potential design of new active organic recyclable packaging materials.

The aim of the present study was to determine the level of association of the spatio-temporal gait parameters in subjects with and without plantar fasciopathy. The second objective was to analyze whether differences in spatio-temporal parameters between both groups exist. Seventy-four subjects divided in two groups participated in the study, one presenting subjects with plantar fasciopathy for more than three months (n = 31), and the other group comprising subjects without plantar fasciopathy (n = 43). The spatio-temporal parameters were measured using Optogait. Decreased step length (p < 0.001), increased contact phase (p < 0.001), increased double support (p < 0.001), increased load response (p < 0.001), increased pre-swing (p < 0.001), increased gait cycle (p = 0.002), decreased stride (p < 0.001), decreased speed (p < 0.001), decreased cadence (p < 0.001), decreased phase flatfoot (p = 0.001), and increased propulsion (p < 0.001) in subjects with PF showed statistically significant differences when compared with the control group.. Furthermore, the level of association between the spatio-temporal parameters was different when comparing the groups. These findings may help when assessing potential plantar fascia injuries, and they may serve as a tool that helps with clinical decision-making, or as a clinical measurement in a treatment and follow-up program.

In this work, Cu2O nanoparticles (NPs) were created in situ on graphene functionalized with Thermomyces lanuginosus lipase (G@TLL) where site-oriented supported TLL acted as template and binder in the presence of copper salt by tailorable synthesis under mild conditions, producing a heterogeneous catalyst. Cu2O NPs were confirmed by XRD and XPS. The TEM microscopy showed that the nanoparticles were homogeneously distributed over the G@TLL surface with sizes of 53 nm and 165 nm. This G@TLL-Cu2O hybrid was successfully used in the degradation of toxic organic compounds such as trichloroethylene (TCE) and Rhodamine B (RhB). In the case of TCE, the hybrid presented a high catalytic capacity, degrading 60 ppm of product in 60 min in aqueous solution and room temperature without the formation of other toxic subproducts. In addition, a TOF value of 7.5 times higher than the unsupported counterpart (TLL-Cu2O) was obtained, demonstrating the improved catalytic efficiency of the system in the solid phase. The hybrid also presented an excellent catalytic performance for the degradation of Rhodamine B (RhB) obtaining a complete degradation (48 ppm) in 50 min in aqueous solution and room temperature and with the presence of a green oxidant as H2O2.

A high-throughput method to obtain several pyrimido[4,5-e][1,4]diazepines is described by a two-step acylation/cyclization sequence from key intermediates 6-amino-5-(amino)methylpyrimidines, which were prepared from the precursor 6-aminopyrimidin-5-carbaldehydes. The acylation is accomplished with haloacyl halides to render ((4-aminopyrimidin-5-yl)-methyl)-2-haloamide intermediates. The cyclization step worked successfully, but depending on the substituents, competitive reactions versus the cyclization to pyrimido[4,5-e][1,4]diazepines were found to afford indolinones or acrylamides which were formed via alternative cyclization or elimination respectively. The pyrimido[4,5-e][1,4]diazepines were derivatized by alkylation at N(9), and a two-step one-pot procedure, cyclization/alkylation, from the ((pyrimidin-5-yl)-methyl)-2-haloamide intermediates was optimized to the formation of these N(9)-substituted derivatives. Keywords: 4(6)-Aminopyrimidines, Diazepines, Fused heterocycles, Acylation, Cyclization

Among the various food items, meat products constitute a significant share in the diets of modern humans [...]

In this paper, the effect of protein purity in three different whey protein grades on the characteristics of algae oil encapsulates obtained via room-temperature electrospraying assisted by pressurized gas (EAPG) encapsulation process was studied. Three different commercial grades of whey protein purity were evaluated, namely 35, 80, and 90 wt.%. Oil nanodroplets with an average size of 600 nm were homogeneously entrapped into whey protein microparticles 3 µm in size. However, the sphericity and the surface smoothness of the microparticles increased by increasing the protein purity in the grades of whey protein studied. The porosity of the microparticles was also dependent on protein purity as determined by nitrogen adsorption–desorption isotherms, being smaller for larger contents of protein. Interestingly, the lowest extractable oil was obtained with WP35, probably due to the high content of lactose. The peroxide values confirmed the superior protective effect of the protein, obtaining the smallest peroxide value for WP90, a result that is consistent with its reduced porosity and with its lower permeability to oxygen, as confirmed by the fluorescence decay–oxygen consumption method. The accelerated stability assay against oxidation confirmed the higher protection of the WP80 and WP90. In addition, the increased content in protein implied a higher thermal stability according to the thermogravimetric analysis. These results further confirm the importance of the adequate selection of the composition of wall materials together with the encapsulation method.

Rolling stock manufacturers face the challenge of manufacturing lightweight high-speed trains without deteriorating comfort. One of the difficulties is to mantain or increase structural stiffness and damping as the car bodies become lighter. Leaving aside active solutions, which are expensive and generally complex to implement, increasing structural damping by means of viscoelastic patches (via Constrained Layer Damping) seems to be a viable solution which is in fact already used for acoustic insulation in automotive, aerospace and even railway applications. Although there are works in the literature that try to optimise viscoelastic panels, this work presents an experimental study with two essential contributions: (i) to analyse the influence of a broad set of design parameters such as type of the constraining layer (uniform or honeycomb), thickness of the viscoelastic layer, location, covered area and continuity between patches; and (ii) to consider absolute and specific (per unit mass) damping depending on the design scenario. To locally increase the structural damping of an existing lightweight structure without compromising its weight, partial application of thin viscoelastic and constraining layers turned out to be the best solution. To enhance structural damping from the design stages, disregarding constraining layer mass by incorporating its stiffness into the overall stiffness of the structure, full coverage with thick viscoelastic layer and a honeycomb constraining layer with a high cross-section moment of inertia turned out to be the best option, reaching modal damping ratios up to 22 times higher than structures without viscoelastic materials.

Single photon sources (SPS) based on semiconductor quantum dot (QD) platforms are restricted to low temperature (T) operation due to the presence of strong dephasing processes. Although the integration of QD in optical cavities provides an enhancement of its emission properties, the technical requirements for maintaining high indistinguishability (I) at high T are still beyond the state of the art. Recently, new theoretical approaches have shown promising results by implementing two-dipole-coupled-emitter systems. Here, we propose a platform based on an optimized five-dipole-coupled-emitter system coupled to a cavity which enables perfect I at high T. Within our scheme the realization of perfect I single photon emission with dissipative QDs is possible using well established photonic platforms. For the optimization procedure we have developed a novel machine-learning approach which provides a significant computational-time reduction for high demanding optimization algorithms. Our strategy opens up interesting possibilities for the optimization of different photonic structures for quantum information applications, such as the reduction of quantum decoherence in clusters of coupled two-level quantum systems.

The success of arrhythmia classification tasks with Machine Learning (ML) algorithms is based on the handcrafting extraction of features from Electrocardiography (ECG) signals. However, feature extraction is a time-consuming trial-and-error approach. Deep Neural Network (DNN) algorithms bypass the process of handcrafting feature extraction since the algorithm extracts the features automatically in their hidden layers. However, it is important to have access to a balanced dataset for algorithm training. In this exploratory research study, we will compare the evaluation metrics among Convolutional Neural Networks (1D-CNN) and Support Vector Machines (SVM) using a dataset based on the merged public ECG signals database TNMG and CINC17 databases. Results: Both algorithms showed good performance using the new, merged ECG database. For evaluation metrics, the 1D-CNN algorithm has a precision of 93.04%, an accuracy of 93.07%, a recall of 93.20%, and an F1-score of 93.05%. The SVM classifier (λ = 10, C = 10 × 109) achieved the best classification metrics with two combined, handcrafted feature extraction methods: Wavelet transforms and R-peak Interval features, which achieved an overall precision of 89.04%, accuracy of 92.00%, recall of 94.20%, and F1-score of 91.54%. As an unique input feature and SVM (λ=10,C=100), wavelet transforms achieved precision, accuracy, recall, and F1-score metrics of 86.15%, 85.33%, 81.16%, and 83.58%. Conclusion: Researchers face a challenge in finding a broad dataset to evaluate ML models. One way to solve this problem, especially for deep learning models, is to combine several public datasets to increase the amount of data. The SVM and 1D-CNN algorithms showed positive results with the merge of databases, showing similar F1-score, precision, and recall during arrhythmia classification. Despite the favorable results for both of them, it should be considered that in the SVM, feature selection is a time-consuming trial-and-error process; meanwhile, CNN algorithms can reduce the workload significantly. The disadvantage of CNN algorithms is that it has a higher computational processing cost; moreover, in the absence of access to powerful computational processing, the SVM can be a reliable solution.

Electrolyzed water is a novel disinfectant and cleaner that has been widely utilized in the food sector for several years to ensure that surfaces are sterilized, and that food is safe. It is produced by the electrolysis of a dilute salt solution, and the reaction products include sodium hydroxide (NaOH) and hypochlorous acid. In comparison to conventional cleaning agents, electrolyzed water is economical and eco-friendly, easy to use, and strongly effective. Electrolyzed water is also used in its acidic form, but it is non-corrosive to the human epithelium and other organic matter. The electrolyzed water can be utilized in a diverse range of foods; thus, it is an appropriate choice for synergistic microbial control in the food industry to ensure food safety and quality without damaging the organoleptic parameters of the food. The present review article highlights the latest information on the factors responsible for food spoilage and the antimicrobial potential of electrolyzed water in fresh or processed plant and animal products.

Antidot lattices made of magnetic thin films are good candidates to be employed in future magnetic recording media. In this manuscript we present a study on the effect of shape and field-induced magnetic anisotropies on the magnetization reversal of 10 nm and 50 nm thick permalloy antidot lattices. Rounded antidot square lattices were fabricated using a combination of electron beam evaporation and laser interference lithography, covering surfaces of a few cm2. We demonstrate that a magnetic anisotropy induced in the samples, as a consequence of an applied magnetic field during growth, competes with the shape anisotropy that dominates the response of the patterned thin films, and that the effect of the field-induced magnetic anisotropy scales with the thickness of the antidot thin films. Finally, we have quantified the anisotropy constant attributable to the uniaxial field-induced magnetic anisotropy in our antidot lattices. These findings are supported by micromagnetic simulations performed using MuMax3.

Consumer demand for specific dietary and nutritional characteristics in their foods has risen in recent years. This trend in consumer preference has resulted in a strong emphasis in the meat industry and scientific research on activities aimed at improving the nutritional value of fermented meat products. These types of meat products are valued by modern consumers due to their nutritional value resulting, among others, from the method of production. One of the major focuses of the current innovations includes the incorporation of bioactive compounds from plant-based food, in relation to the replacement of additives that may raise concerns among consumers (mainly nitrate and nitrite) as well as the modification of processing conditions in order to increase the content of bioactive compounds. Many efforts have been focused on reducing or eliminating the presence of additives, such as curing agents (nitrite or nitrate) in accordance with the idea of “clean label”. The enrichment of fermented meat products in compounds from the plant kingdom can also be framed in the overall strategies of functional meat products design, so that the meat products may be used as the vehicle to deliver bioactive compounds that may exert benefits to the consumer.

Adsorption systems are characterized by challenging behavior to simulate any numerical method. A novel field of study emerged within the numerical method in the last two years: the physics-informed neural network (PINNs), the application of artificial intelligence to solve partial differential equations. This is a complete new standpoint for solving engineering first-principle models, which up to that date was not explored in the field of adsorption systems. Therefore, this work proposed the evaluation of PINN to address the numerical solutions of a fixed-bed column where a monoclonal antibody is purified. The PINNs solution is compared with a traditional numerical method. The results show the accuracy of the proposed PINNs when compared with the numerical method. This points towards the potential of this technique to address complex numerical problems found in chemical engineering.

The chemical composition of any food material can be analyzed well by employing various analytical techniques. The physical properties of food are no less important than chemical composition as results obtained from authentic measurement data are able to provide detailed information about the food. Several techniques have been used for years for this purpose but most of them are destructive in nature. The aim of this present study is to identify the emerging techniques that have been used by different researchers for the analysis of the physical characteristics of food. It is highly recommended to practice novel methods as these are non-destructive, extremely sophisticated, and provide results closer to true quantitative values. The physical properties are classified into different groups based on their characteristics. The concise view of conventional techniques mostly used to analyze food material are documented in this work.

Since the very first landmark report by Geim and Novoselov in 2004 on graphene [...]

The electrospinnability of FucoPol, a bacterial exopolysaccharide, is presented for the first time, evaluated alone and in combination with other polymers, such as polyethylene oxide (PEO) and pullulan. The obtained fibers were characterized in terms of their morphological, structural and thermal properties. Pure FucoPol fibers could not be obtained due to FucoPol’s low water solubility and a lack of molecular entanglements. Nanofibers were obtained via blending with PEO and pullulan. FucoPol:PEO (1:3 w/w) showed fibers with well-defined cylindrical structure, since the higher molecular weight of PEO helps the continuity of the erupted jet towards the collector, forming stable fibers. WAXS, DSC and TGA showed that FucoPol is an amorphous biopolymer, stable until 220 °C, whereas FucoPol-PEO fibers were stable until 140 °C, and FucoPol:pullulan fibers were stable until 130 °C. Interestingly, blended components influenced one another in intermolecular order, since new peaks associated to intermolecular hierarchical assemblies were seen by WAXS. These results make FucoPol-based systems viable candidates for production of nanofibers for packaging, agriculture, biomedicine, pharmacy and cosmetic applications.