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The objective of this study was to analyze visual representations of redox reactions and related content in four Brazilian secondary school chemistry textbooks. The study aimed to identify which representations were used and to evaluate how these representations were linked to one another and to the main text. Data were analyzed regarding representational levels and the degree of relatedness between the different levels and the main text. Further analysis focused on the intended function of images and which curriculum orientation they indicated. The sample was comprised of 286 visual representations. The results showed that most of the visual representations merely served a decorative function and were not explicitly used to further understanding of the content in the main text. The findings indicated that the textbooks in this sample prioritized two separate levels of representation: The macroscopic and the symbolic. Only a few submicroscopic and multilevel representations could be found. The textbook illustrations indicated a strong "structure of the discipline" orientation of the curriculum, which was illustrated with orientations taken from everyday life, technology, and industry. It emphasizes the importance of using illustrations in textbooks, because of its influence on the construction of concepts, in particular the concept of redox reactions. Based on this research, it is possible for chemistry teachers to observe the limitation of these materials and carefully select the textbook used in their curricula. Moreover, the results can contribute to improving the quality of textbooks.

Students determine the iron mass in dietary supplements using four colorimetric assays. These colorimetric assays were selective for Fe[superscript 3+]. It was complexed by thiocyanide, salicylate, gallic acid, and Fe(CN)[subscript 6][superscript 4-], forming blood-red, red, violet, and blue complexes, respectively. The [lambda][subscript max] of these complexes were 447, 480, 570, and 700 nm, respectively. These assays were scaled-down, where 1 mL of chromogenic reagent was mixed with 0.1 mL of sample. Salicylic acid, gallic acid, and K[subscript 4][Fe(CN)[subscript 6]] were harmless and cheap chromogenic reagents that could be used instead of traditional chromogenic reagents such as KSCN and phenanthroline. Quantitative analysis was carried out using absorbance measured at [lambda][subscript max] of each assay (standard method) and 96-well-plate digital images obtained with a desktop scanner (proposed method). The matrix effect was investigated by comparing the standard addition curves with the external calibration curves, where no matrix effect was found. Results obtained using the four assays were compared using hypothesis tests such as one-way ANOVA, post-hoc tests, and plots. Investigation of interactions between samples and assays was carried out using two-way ANOVA. Statistical tests were carried out using open-source and graphical user interface programs (JASP and R Commander). The student learning goals of this experiment include comparing multiple assays using hypothesis tests. Learn about the principles of green chemistry, method scale-down, and matrix effect.

Students quantified the protein content in beer, milk, powdered milk, and whey protein using the Bradford assay. The assay was carried out using absorbance measured at 595 nm (standard method) and 96-well-plate images (proposed method). They built analytical curves using bovine serum albumin (BSA) and casein and determined that protein type affected the Bradford assay. They also determined figures of merit such as the limit of detection (LOD), the limit of quantification (LOQ), linear working range, sensitivity, precision (standard deviation, F-test), and accuracy (percent error, t test). In addition, an interference test was carried out using nitrogen-rich compounds, organic bases, and amino acids, and it was shown that the Bradford assay was not affected by these compounds. Student learning outcomes were assessed by a final test using Microsoft Forms. As a learning model, students can determine the protein content in various food samples using just sample dilution, without the need for intricate sample preparation procedures.

This work describes an alternative approach for introducing the concept of pH in high school. We develop an experimental protocol to demonstrate in classroom as pH affects the life of microorganisms. At the same time, we constructed low-cost equipment and a homemade culture media using ordinary products, which they are easily found by the teachers in any commercial store. It was observed that in pH lower than 3 and higher than 13 the growth of microorganisms is inhibited. We applied this interdisciplinary activity to students from six different schools. The results showed that teaching the concept of pH, contextualized with its effect on the growth of microorganism, was significant for the students. Our goal with this kind of activity is to allow students to understand the concept of pH through the application of knowledge allowing them to intervene in their daily lives.

Visualization can be a motivating way to teach students about molecules. Nowadays, the available experimental data and accurate computational results allow students to build realistic and accurate molecular models. These models include the representation of complex systems such as proteins, membranes, or nanotubes. However, the visualization of these three-dimensional (3D) structures can be challenging, complex, or even abstract for most people. To make the visualization easier and more motivating, BioSIM Augmented Reality (BioSIM[superscript AR]) was developed as a free online software program to provide a new way to visualize and interact with 3D molecular models in a virtual environment. Using augmented reality (AR) and quick response code technologies, BioSIM[superscript AR] provides tangible models of molecules to help illustrate chemical concepts. BioSIM[superscript AR] runs on any electronic device, including mobile phones, tablets, laptops, or desktop computers with a camera and an internet connection, without requiring the installation of additional software. This software program helps people visualize and understand concepts about atoms and molecules, and their characteristics. BioSIM[superscript AR] is freely available at https://ar.biosim.pt/.

This work describes a simple talking calorimeter for the visually impaired based on the Arduino Uno without any shield. An electronic interface was designed using a Wheatstone bridge, a thermistor, or an operational amplifier (opamp). The temperature values are communicated by a loudspeaker connected to pulse-width modulation (PWM) digital output pins 3 and 11 of the Arduino Uno. The system is based on the Talkie library for Arduino Uno. This library was developed using Linear Predictive Coding and includes about 1000 English words. Two new Talkie libraries were constructed, one for Portuguese and another for German. This device can be easily implemented in any teaching laboratory with extremely reduced costs.

In 2013, with a 30% state budget cut after the Great Recession, many of the 450,000 California State University (CSU) students across the 23-campus system were unable to enroll in courses they needed to move closer to graduation; there was a lack of available course sections. In addition to a reduced number of seats available for students, 30% to 40% of students, particularly in science, technology, engineering, and math (STEM) courses, were failing and needed to repeat those courses. This left a reduced number of seats available for firsttime students, causing "bottlenecks" and low graduation rates. To address this issue, CSU's Office of the Chancellor received funding from then Governor Jerry Brown. The focus of the funding was to innovate in teaching and learning so that more students succeeded in passing the course the FIRST time. They would then not be repeating courses and keeping other students from enrolling who needed to take the course. Since the 2013-14 academic year, all 23 CSU campuses have been given the opportunity and support to develop and implement innovative strategies to eliminate course bottlenecks as impediments to graduation. After 5 years of engaging faculty cohorts to redesign bottleneck courses across the 23 campus system, CSU now publicly showcases over 700 teaching ePortfolios, containing a substantial body of course redesign summaries. These ePortfolios include course demographics, faculty redesign methods, resulting implementations, reflections, student feedback, and course outcomes.

Fungal infections are a significant threat to human health and the environment. The emergence of multidrug-resistant strains of fungi and the growing prevalence of azole resistance in invasive fungal infections exacerbate the problem, with efflux pumps being a major cause of antifungal resistance and a prime target for several counteractive strategies. In Candida albicans, the ATP-binding cassette superfamily transporter CaCdr1p is the predominant efflux pump involved in azole resistance. Marine organisms have unique phenotypic characteristics to survive in challenging environments, resulting in biologically active compounds. The cyclodepsipeptides unnarmicin A and C have shown promising results as inhibitors of rhodamine 6G efflux in cells expressing CaCdr1p. Herein, a series of unnarmicin analogues were designed and docked against a CaCdr1p efflux pump based on the cryogenic electron microscopy structure available to select the most promising compounds. Analogue 33 was predicted to be the best considering its high affinity for the efflux pump and pharmacokinetic profile. These results pave the way for further synthesis and in vitro biological studies of novel unnarmicins seeking a synergistic effect with fluconazole.

The rise of antibiotic-resistant bacterial strains has become a critical health concern. According to the World Health Organization, the market introduction of new antibiotics is alarmingly sparse, underscoring the need for novel therapeutic targets. The LytR-CpsA-Psr (LCP) family of proteins, which facilitate the insertion of cell wall glycopolymers (CWGPs) like teichoic acids into peptidoglycan, has emerged as a promising target for antibiotic development. LCP proteins are crucial in bacterial adhesion and biofilm formation, making them attractive for disrupting these processes. This study investigated the structural and functional characteristics of the LCP domain of LytR from Streptococcus dysgalactiae subsp. dysgalactiae. The protein structure was solved by X-ray Crystallography at 2.80 Å resolution. Small-angle X-ray scattering (SAXS) data were collected to examine potential conformational differences between the free and ligand-bound forms of the LytR LCP domain. Additionally, docking and molecular dynamics (MD) simulations were used to predict the interactions and conversion of ATP to ADP and AMP. Experimental validation of these predictions was performed using malachite green activity assays. The determined structure of the LCP domain revealed a fold highly similar to those of homologous proteins while SAXS data indicated potential conformational differences between the ligand-free and ligand-bound forms, suggesting a more compact conformation during catalysis, upon ligand binding. Docking and MD simulations predicted that the LytR LCP domain could interact with ADP and ATP and catalyze their conversion to AMP. These predictions were experimentally validated by malachite green activity assays, confirming the protein’s functional versatility. The study provides significant insights into the structural features and functional capabilities of the LCP domain of LytR from S. dysgalactiae subsp. dysgalactiae. These findings pave the way for designing targeted therapies against antibiotic-resistant bacteria and offer strategies to disrupt bacterial biofilm formation.

Abstract A key strategy for minimizing our reliance on precious metals is to increase the fraction of surface atoms and improve the metal-support interface. In this work, we employ a solvent/ligand/counterion-free method to deposit copper in the atomic form directly onto a nanotextured surface of graphitized carbon nanofibers (GNFs). Our results demonstrate that under these conditions, copper atoms coalesce into nanoparticles securely anchored to the graphitic step edges, limiting their growth to 2–5 nm. The resultant hybrid Cu/GNF material displays high selectivity in the CO2 reduction reaction (CO2RR) for formate production with a faradaic efficiency of ~94% at -0.38 V vs RHE and a high turnover frequency of 2.78 × 106 h-1. The Cu nanoparticles adhered to the graphitic step edges significantly enhance electron transfer to CO2. Long-term CO2RR tests coupled with atomic-scale elucidation of changes in Cu/GNF reveal nanoparticles coarsening, and a simultaneous increase in the fraction of single Cu atoms. These changes in the catalyst structure make the onset of the CO2 reduction potential more negative, leading to less formate production at -0.38 V vs RHE, correlating with a less efficient competition of CO2 with H2O for adsorption on single Cu atoms on the graphitic surfaces, revealed by density functional theory calculations.

Environmental Education (EE) is an essential theme that must be addressed broadly and effectively in High School. Brazilian High School students are aware of environmental issues that devastate the country they live in. Thus, the Base Nacional Comum Curricular (BNCC) is a mandatory document whose norms guide and define common learning results of curricula in all public and private schools in Brazil. Therefore, this study aimed at analyzing how EE was inserted into the latest version of the High School BNCC. It is an exploratory study which analyzed documents and bibliographic sources. Regarding its methodology, key words connected to EE and to promotion of sustainability in High School were used for the search in the document. After data issued by the BNCC were analyzed, we perceived that EE is briefly inserted in the document; as a result, it is neither taught nor practiced as it should be. Since EE is generically treated and poorly addressed, it does not contribute to a broad, transversal and integrative approach. Teaching EE and sustainability in High School is an important step to achieve legally established goals, go beyond theories and, mainly, put into practice speeches given by the Brazilian public management.

Exploring the triacylglycerols composition in milk samples from different ruminant species is crucial for dairy product development. Identifying the fatty acid (FA) composition in human milk is essential and is usually performed using gas chromatography (GC). Heat maps are useful for visualizing these results, aiding in pattern identification and relationships between samples and variables. Additionally, nuclear magnetic resonance (NMR) spectroscopy provides important qualitative and quantitative information about fatty acids (FA). In the present study, we compare the fatty acid composition in samples of HM, cow milk, and goat milk, as well as to demonstrate their positional distribution in triacylglycerols (TAGs). Human milk contains 49.21% saturated fatty acids (SFAs), 34.32% monounsaturated fatty acids (MUFA), and 16.47% polyunsaturated fatty acids (PUFA), including 2.14% docosahexaenoic acid (DHA) and 13.02% linoleic acid (LA). On the other hand, cow and goat milk have higher proportions of SFAs (56.2 and 58.02%, respectively) and MUFAs (40.56 and 40.95%, respectively), but lower amounts of PUFAs (3.24 and 1.03%, respectively), with significantly lower quantities of DHA (0.03 and 0.43%, respectively) and LA (1.46 and 2.76%, respectively). Additionally, fatty acids in ruminant milk mainly consist of long-chain fatty acids (LCFAs), with oleic acid being the most abundant.

Mixed oxides of pyrochlore structure of the type La2Zr2O7 and La2M0.3Zr1.7O7 (M = Fe or Ni) were synthesized through the modified proteic method and calcined at 900 °C for 2 h, this is a synthesis route not yet explored for materials with this structure and were characterized by X-ray diffraction, scanning electron microscopy images, point of zero charge (PZC) and specific surface area. Its abilities to remove pollutants from aqueous media by adsorption process were investigated using a model compound. Data analysis revealed that the synthesized materials correspond to the pyrochlore phase (La2Zr2O7). They present particulate morphology with grains of different sizes and pores in their structure. The results of the adsorption studies show that the materials are efficient adsorbents for the removal of model compound in aqueous media, with efficiency above 90%. The adsorption kinetics of the compound in the adsorbents was studied. The materials were applied in reuse studies five times and maintained high efficiencies, highlighting the better performance presented by the material without doping. The obtained adsorbents were also submitted to removal of contaminants of industrial effluent tests and compared with the silica gel and activated carbon materials and also proved to be promising materials.

IntroductionOverusing and misusing pesticides, including paraquat (PQ), have led to numerous environmental contamination complications. PQ is an emerging bio-accumulative contaminant that is present in environmental aqueous matrices. Adsorption techniques are part of a set of technologies applied in ecological remediation, known for their high effectiveness in removing aqueous PQ. A study of the PQ adsorption capacity of three cyclodextrin–silica nanocomposites (α-CDSi, β-CDSi, and γ-CDSi) from contaminated waters is presented in this paper.MethodsThe cyclodextrin–silica nanocomposites were synthesized via an esterification reaction between the inorganic matrix and cyclodextrins (CDs) (α, β, and γ) and were characterized physicochemically by spectroscopic, thermal, and surface methods. Their PQ removal performance from contaminated aqueous media was studied under different experimental conditions.Results and DiscussionThe results showed a fast adsorptive response in removal treatment studies over time. Adsorption capacities of 87.22, 57.17, and 77.27 mg.g−1 were found for α-CDSi, β-CDSi, and γ-CDSi, respectively, at only 30 min of treatment. Thermodynamic studies indicated spontaneous and exothermic adsorption processes. The removal assays responded mainly to physisorption mechanisms with contributions from chemisorption mechanisms. Spectroscopic assays showed a strong interaction of PQ with the adsorbents used. Innovative CDSi nanocomposites have proven to be highly efficient in applying aqueous PQ remediation, thus proving to be sustainable adsorbents of contaminants of emerging importance worldwide.

Species from Pavonia genus (Malvaceae) are traditionally used as antioxidant, n anti inflammatory and antimicrobial remedies. Previous studies have revealed their diversity of specialized metabolites widely used in the development of new medicines. This is the first study on Pavonia glazioviana Gurke, a Brazilian species known as “Malva da Chapada”. The research led to identify fifteen compounds: 132 (S) hydroxy pheophytin a; and 132(S) hydroxy 173 ethoxyphaeophorbide, n decanol, cycloart 23Z ene 3β,25 diol, cycloart 24S 25 ene 3β,24 diol, sitosterol 3 O β D glucopyranoside, stigmasterol 3 O β D glucopyranoside, quercetin, acacetin, kaempferol, tiliroside, 5 hydroxy 3,7,8,4’ tetramethoxyflavone, 5,7 dihydroxy 3,8,4’ trimethoxyflavone, 5,7 dihydroxy 4’ methoxyflavone, 5,7,4’ trihydroxy 3,8 dimethoxyflavone and 5,7,4’ trihydroxy 3 methoxyflavone. The major flavonoids were tested for their antimicrobial activity, and the compound 5,7 dihydroxy 3,8,4’ trimethoxyflavone showed strong activity against Escherichia coli (MIC = 512 μg mL1), Pseudomonas aeruginosa (MIC = 512 μg mL1), Candida albicans (MIC = 512 μg mL1), Candida tropicalis (MIC = 512 μg mL1), Candida parapsilosis (MIC = 512 μg mL1), Aspergillus flavus (MIC = 512 μg mL1) and A. fumigantus (MIC = 512 μg mL1). The total phenolic content, flavonoid content, and radical scavenging potential were determined showing its great production of phenolics and flavonoids, along with interesting radical scavenging potential (DPPH EC50 = 6.36 ± 0.029 mg mL 1). Our findings contributed to characterize P. glazioviana as a source of methoxylated flavonoids with antimicrobial potential.

We report on a computational chemistry course for undergraduate students that successfully incorporated a research project on the design of new contrast agents for magnetic resonance imaging and shift reagents for in vivo NMR. Course outcomes were positive: students were quite motivated during the whole year--they learned what was required of them, including the difficult theory determining the behavior of molecules represented by onscreen images from the computer modeling software. We discuss the students' results as well as the advantages and disadvantages of teaching this sort of course from both the students' and teachers' points of view.

Zilucoplan is a synthetic macrocyclic peptide approved by the Food and Drug Administration (FDA), in October 2023, for the treatment of generalized myasthenia gravis. It is considered as an orphan drug that causes the inhibition of terminal complement cascade activation with a dual mechanism of action preventing the formation of the membrane attack complex (MAC) and the destruction of the neuromuscular junction. This drug has been demonstrated to be able to treat the generalized myasthenia gravis without significant adverse effects, with good efficacy, safety, and tolerability profile. Zilucoplan is not only innovative and promising in the therapeutics of generalized myasthenia gravis, but it could also be beneficial for the treatment of other diseases as well as a model for synthesis of analogues to improve pharmacological profile.

Abstract Cell-penetrating peptides (CPPs) are short chains of amino acids that have shown remarkable potential to cross the cell membrane and deliver coupled therapeutic cargoes into cells. Designing and testing different CPPs to target specific cells or tissues is crucial to ensure high delivery efficiency and reduced toxicity. However, in vivo/in vitro testing of various CPPs can be both time-consuming and costly, which has led to interest in computational methodologies, such as Machine Learning (ML) approaches, as faster and cheaper methods for CPP design and uptake prediction. However, most ML models developed to date focus on classification rather than regression techniques, because of the lack of informative quantitative uptake values. To address these challenges, we developed POSEIDON, an open-access and up-to-date curated database that provides experimental quantitative uptake values for over 2,300 entries and physicochemical properties of 1,315 peptides. POSEIDON also offers physicochemical properties, such as cell line, cargo, and sequence, among others. By leveraging this database along with cell line genomic features, we processed a dataset of over 1,200 entries to develop an ML regression CPP uptake predictor. Our results demonstrated that POSEIDON accurately predicted peptide cell line uptake, achieving a Pearson correlation of 0.87, Spearman correlation of 0.88, and r2 score of 0.76, on an independent test set. With its comprehensive and novel dataset, along with its potent predictive capabilities, the POSEIDON database and its associated ML predictor signify a significant leap forward in CPP research and development. The POSEIDON database and ML Predictor are available for free and with a user-friendly interface at https://moreiralab.com/resources/poseidon/ , making them valuable resources for advancing research on CPP-related topics. Scientific Contribution Statement: Our research addresses the critical need for more efficient and cost-effective methodologies in Cell-Penetrating Peptide (CPP) research. We introduced POSEIDON, a comprehensive and freely accessible database that delivers quantitative uptake values for over 2,300 entries, along with detailed physicochemical profiles for 1,315 peptides. Recognizing the limitations of current Machine Learning (ML) models for CPP design, our work leveraged the rich dataset provided by POSEIDON to develop a highly accurate ML regression model for predicting CPP uptake. Graphical Abstract

An extensive description of the Modeling Chemical and Biological Systems study organized in different practical projects is presented. The course has a highly favorable effect on students, who make perfect presentations, and it also encourages more students to join the course.

Summary: The search and development of new quorum-sensing (QS) inhibitors are ongoing processes for biofilm control. Here, we present a protocol for in silico characterization of natural-based molecules as QS inhibitors. We describe steps for preparing models of protein receptors for virtual screening. We then detail procedures for construction and virtual screening of phytochemical libraries and hit picking to be experimentally validated by in vitro assays. This protocol allows exploration of a broad range of potential inhibitors for a specific target.For complete details on the use and execution of this protocol, please refer to Fernandes et al.1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Interfacial solar steam generation is considered as economical and more effective implementation of Solar steam generation (SSG) where solar energy is concentrated at the liquid surface via the utilization of heat localization materials (HLM). Herein we report the fabrication of an HLM constituted of a nanocomposite absorber of graphitic carbon nitride (g-C3N4) and covellite copper sulfide (CuS) supported on a mixed cellulose ester membrane, with a substrate of air laid paper-wrapped polystyrene foam. This structure allowed for strong broad-spectrum absorbance, increased hydrophilic character and minimal thermal losses. The HLM system absorbed 98% of the material and had an evaporation rate of 2.58 kgs per square meter per hour. This is twice the evaporation rate of water tested under the same conditions. Moreover, as fabricated HLM was also incorporated in a solar still in order to assess its practical performance in solar distillation. Initial studies proved that HLM modified solar still was more effective than conventional solar stills.

The increase in the fleet of motor vehicles circulating in urban centers is one of the main generators of gaseous pollutants harmful to human health and the environment. Pollutants can be economically and effectively monitored through passive sampling. This study aims to estimate NO2 levels on roads of Fortaleza city /CE using the passive sampling method. 12 campaigns covered the rainy (March-June) and the dry (July-November) seasons in 2019. The seasonal averages of NO2 in the rainy season were higher than the dry one, and Almirante Rubim Street showed the greatest difference in the averages: 26.6 µg m-3 in the rainy and 19.3 µg m-3 in the dry season. The principal component analysis applied to the averages of NO2 concentration in the rainy and dry seasons, vehicle traffic and Height of the road/width ratio indicated that components 1, 2 and 3 explain 94.4% of the studied cases. Passive sampling proved to be efficient, contributing to the production of unpublished data about NO2 levels in streets of Fortaleza/Ceará/Brazil from mobile sources.

As hotspots of the global carbon cycle, lakes can regulate climate change while being regulated by it via a feedback loop. As ecosystem metabolism is considered to be a sentinel to these changes, we used high-frequency measurements and the inverse modeling approach to study the temporal dynamic of gross primary production (GPP), respiration (R), and net ecosystem production (NEP) at surface waters of a tropical lake, which lost about 60% of its volume in almost 10 years. This water loss and the return of the average rainfall led to an increased concentration of nitrogen, phosphorus, and dissolved organic carbon and decreased water transparency and light availability. During the post-drought period, epilimnetic GPP increased by 40% compared with the pre-drought period, and R surpassed GPP during the mixing period of the lake. We discuss that this modification results from higher carbon and nutrient concentrations, lower light availability, and a change in the lake stratification pattern. Surface water metabolism changed due to meteorological and hydrological drought, and it may continue to change under the ongoing variation in rainfall patterns, temperature, and human disturbances.

The use of extracts rich in bioactive compounds is becoming increasingly common in the food, cosmetics, and pharmaceutical industries for the production of functional products. Araticum is a potential fruit to be analyzed due to its content of phenolic compounds, carotenoids and vitamins, with antioxidant properties. Therefore, this study aimed to investigate the effect of ultrasound on total phenolic compounds, total carotenoids, ascorbic acid, color, turbidity and rheology in araticum juice. Response surface methodology based on a central composite design was applied. Araticum juice was subjected to sonication at amplitude levels ranging from 20 to 100 % of the total power (400 W) at a constant frequency of 20 kHz for different durations (2 to 10 min). Morphological analysis was conducted to observe microscopic particles, and viscosity and suitability to rheological models (Newtonian, Power Law, and Herschel-Bulkley) were assessed. The ultrasonic probe extraction method was compared to the control juice. According to the responses, using the desirability function, the optimal conditions for extraction were determined to be low power (low amplitude) applied in a short period of time or low power applied in a prolonged time. These conditions allowed an ultrasonic probe to act on releasing bioactive compounds without degrading them. All three rheological models were suitable, with the Power Law model being the most appropriate, exhibiting non-Newtonian pseudoplastic behavior.

In order to extract meaningful interpretation from the large data and provide their value to the application areas, chemical data analysis has become a serious challenge in the development and applications of new protocols, technique and methodologies for the mathematical modelling communities and other data science societies. Therefore, in the present work a rapid and robust box-and-whisker plot and multivariate principal component statistical techniques (PCA) are being proposed for the evaluations of the thermodynamic molecular properties data of the benign fuel structures. We observed that, the box-and-whisker plot technique successfully explored all of the thermochemical molecular properties precisely, and described symmetrical distribution of the data along the median values with respect to the rise in temperature. Moreover, applying the PCA technique, the score-plots of PCs diagnosed the peculiar molecular properties variations after a certain peak of temperature with descendant variation in the statistical parameters. Furthermore, PCA parameters not only segregated the thermodynamic properties of propanol and butanol but also, their variations with the temperature. Thus, we concluded that, Box-whisker and PCA statistical techniques are robust and rapid method for the assessment and evaluation of the large molecular thermodynamic quantities data.

This work provides insight into carbamazepine polymorphs (Forms I, II, III, IV, and V), with reports on the cytoprotective, exploratory, motor, CNS-depressant, and anticonvulsant properties of carbamazepine (CBZ), carbamazepine formulation (CBZ-F), topiramate (TOP), oxcarbazepine (OXC), and diazepam (DZP) in mice. Structural analysis highlighted the significant difference in molecular conformations, which directly influence the physicochemical properties; and density functional theory description provided indications about CBZ reactivity and stability. In addition to neuron viability assessment in vitro, animals were treated orally with vehicle 10 mL/kg, as well as CBZ, CBZ-F, TOP, OXC, and DZP at the dose of 5 mg/kg and exposed to open-field, rotarod, barbiturate sleep induction and pentylenetetrazol (PTZ 70 mg/kg)-induced seizure. The involvement of GABAergic mechanisms in the activity of these drugs was evaluated with the intraperitoneal pretreatment of flumazenil (2 mg/kg). The CBZ, CBZ-F, and TOP mildly preserved neuronal viability. The CBZ-F and the reference AEDs potentiated barbiturate sleep, altered motor activities, and attenuated PTZ-induced convulsion. However, flumazenil pretreatment blocked these effects. Additional preclinical assessments could further establish the promising utility of CBZ-F in clinical settings while expanding the scope of AED formulations and designs.

Polyploid Giant Cancer Cells (PGCCs) have been recognized as tumor cells that are resistant to anticancer therapies. However, it remains unclear whether their presence in the bloodstream can be consistently detected and utilized as a clinical marker to guide therapeutic anticancer regimens. To address these questions, we conducted a retrospective study involving 228 patients diagnosed with six different types of carcinomas (colon, gastric, NSCLC, breast, anal canal, kidney), with the majority of them (70%) being non-metastatic. Employing a highly sensitive liquid biopsy approach, ISET®, and cytopathological readout, we isolated and detected circulating PGCCs in the patients’ blood samples. PGCCs were identified in 46 (20.18%) out of 228 patients, including in 14.47% of 152 non-metastatic and 29.85% of 67 metastatic cases. Patients were subsequently monitored for a mean follow up period of 44.74 months (95%CI: 33.39–55.79 months). Remarkably, the presence of circulating PGCCs emerged as a statistically significant indicator of poor overall survival. Our findings suggest that circulating PGCCs hold promise as a reliable prognostic indicator. They underscore the importance of further extensive investigations into the role of circulating PGCCs as a prognostic marker and the development of anti-PGCC therapeutic strategies to improve cancer management and patient survival.

The rapid resistance developed by pathogenic microorganisms against the current antimicrobial pool represents a serious global public health problem, leading to the search for new antibiotic agents. The scorpion Tityus stigmurus, an abundant species in Northeastern Brazil, presents a rich arsenal of bioactive molecules in its venom, with high potential for biotechnological applications. However, venom cytotoxicity constitutes a barrier to the therapeutic application of its different components. The objective of this study was to produce T. stigmurus-venom-loaded cross-linked chitosan nanoparticles (Tsv/CN) at concentrations of 0.5% and 1.0% to improve their biological antimicrobial activity. Polymeric nanoparticles were formed with a homogeneous particle size and spherical shape. Experimental formulation parameters were verified in relation to mean size (78%). Tsv/CN 1.0% demonstrated an ability to increase the antimicrobial venom effect against Staphylococcus aureus bacteria, exhibiting an MIC value of 44.6 μg/mL. It also inhibited different yeast species of the Candida genus, and Tsv/CN 0.5% and 1.0% led to a greater inhibitory effect of C. tropicalis and C. parapsilosis strains, presenting MIC values between 22.2 and 5.5 µg/mL, respectively. These data demonstrate the biotechnological potential of these nanosystems to obtain a new therapeutic agent with potential antimicrobial activity.

Identification of the individuals having impaired kidney function is essential in preventing the complications of this disease. We measured 1009 metabolites at the baseline study in 10,159 Finnish men of the METSIM cohort and associated the metabolites with an estimated glomerular filtration rate (eGFR). A total of 7090 men participated in the 12-year follow-up study. Non-targeted metabolomics profiling was performed at Metabolon, Inc. (Morrisville, NC, USA) on EDTA plasma samples obtained after overnight fasting. We applied liquid chromatography mass spectrometry (LC-MS/MS) to identify the metabolites (the Metabolon DiscoveryHD4 platform). We performed association analyses between the eGFR and metabolites using linear regression adjusted for confounding factors. We found 108 metabolites significantly associated with a decrease in eGFR, and 28 of them were novel, including 12 amino acids, 8 xenobiotics, 5 lipids, 1 nucleotide, 1 peptide, and 1 partially characterized molecule. The most significant associations were with five amino acids, N-acetylmethionine, N-acetylvaline, gamma-carboxyglutamate, 3-methylglutaryl-carnitine, and pro-line. We identified 28 novel metabolites associated with decreased eGFR in the 12-year follow-up study of the METSIM cohort. These findings provide novel insights into the role of metabolites and metabolic pathways involved in the decline of kidney function.

This study investigated the synergistic effects of three protein concentrates from legumes (pea, lentil, and lima bean) as emulsifiers and stabilizers of oil-in-water (O/W) emulsions using a simplex-centroid mixture design. The aim was to check whether proteins combined in different proportions have better emulsifying properties than isolated proteins. During this study, each protein concentrate was characterized by different evaluated parameters: emulsifying activity, emulsion stability, accelerated stability test, thermal coagulation time, stability to coalescence, and others. After statistical analysis mixture optimization, it was found that the best formulation for stabilizing O/W emulsion under the tested conditions (2% total protein; 3% sunflower oil) was the protein blend containing 21.21% pea, 32.78% lentil, and 46.01% fava bean. This blend exhibited better emulsification properties compared to the individual proteins.

Existing literature presents multiple perspectives on quality within organizational contexts. Although these perspectives may differ, they universally emphasize the importance of meeting customer expectations regarding products/services. Consequently, organizations are dedicated to addressing customer requirements to foster elevated satisfaction levels. This study aims to assess customer satisfaction in water laboratories and develop a predictive model using artificial neural networks to improve service quality. A methodology was devised, integrating principles from thermodynamics with logic programming for knowledge representation and reasoning. Data were collected from 412 participants of both genders, aged 22 to 79 years old, using a questionnaire covering six specific areas, i.e., customer service, quality of service provided, support documentation, technical support, billing and payment, and online services and tools. While customer opinions were largely positive, the study identified areas for improvement, including clarity and effectiveness in responses to inquiries, reliability of results, clarity of analysis reports, usefulness of test interpretation guidelines, inclusion of legal information, billing options, and online services. Differences in satisfaction were noted based on socio-demographic factors such as age and academic qualifications. The findings offer a framework (an ANN-based model) for future evaluations and improvements in services, highlighting the importance of addressing specific customer needs to enhance satisfaction.

This study aimed to evaluate the genomic profile of the Antarctic marine Curtobacterium sp. CBMAI 2942, as well as to optimize the conditions for chitinase production and antifungal potential for biological control. Assembly and annotation of the genome confirmed the genomic potential for chitinase synthesis, revealing two ChBDs of chitin binding (Chi C). The optimization enzyme production using an experimental design resulted in a 3.7-fold increase in chitinase production. The chitinase enzyme was identified by SDS-PAGE and confirmed through mass spectrometry analysis. The enzymatic extract obtained using acetone showed antifungal activity against the phytopathogenic fungus Aspergillus sp. series Nigri CBMAI 1846. The genetic capability of Curtobacterium sp. CBMAI 2942 for chitin degradation was confirmed through genomic analysis. The basal culture medium was adjusted, and the chitinase produced by this isolate from Antarctica showed significant inhibition against Aspergillus sp. Nigri series CBMAI 1846, which is a tomato phytopathogenic fungus. This suggests that this marine bacterium could potentially be used as a biological control of agricultural pests.

A cross-sectional study was conducted to biomechanically characterize Isabel’s workout (30 snatch repetitions with 61 kg fixed weight), focusing on eventual changes in knee, hip and shoulder angles. A three-dimensional markerless motion capture system was used to collect data from 11 highly trained male crossfitters along the Isabel workout performed at maximal effort. The routine was analyzed globally and in initial, middle and final phases (10, 20 and 30 repetitions, respectively). Lift total time increased (1.51 ± 0.18 vs. 1.97 ± 0.20 s) and maximal lift velocity (2.64 ± 0.12 vs. 2.32 ± 0.13 m/s) and maximal lift power (15.58 ± 2.34 vs. 13.80 ± 2.49 W/kg) decreased from the initial to final phases, while the time from lift until the bar crossed the hip and shoulder (34.20 ± 4.00 vs. 27.50 ± 5.10 and 39.70 ± 16.80 vs. 30.90 ± 13.90%) decreased along the Isabel workout. In addition, a decrease in hip flexion was observed during the last two phases when the bar crosses the knee (62.62 ± 24.80 vs. 53.60 ± 19.99°). Data evidence a decrease in the power profile and a change in hip flexion throughout the Isabel workout, without compromising the other joints.

The efficient use of depleted gas reservoirs for hydrogen storage is a promising solution for transitioning to carbon-neutral energy sources. This study proposes an analytical framework for estimating hydrogen storage capacity using a comprehensive material balance approach in depleted gas reservoirs. The methodology integrates basic reservoir engineering principles with thermodynamic considerations to accurately estimate hydrogen storage capacity in both volumetric drive and water drive gas reservoirs through an iterative approach based on mass conservation and the real gas law. This framework is implemented in a Python program, using the CoolProp library for phase behavior modeling with the Soave–Redlich–Kwong (SRK) equation of state. The methodology is validated with numerical simulations of a tank model representing the two reservoir drive mechanisms discussed. Also, a case study of a synthetic complex reservoir demonstrates the applicability of the proposed approach to real-world scenarios. The findings suggest that precise modeling of fluid behavior is crucial for reliable capacity estimations. The proposed analytical framework achieves an impressive accuracy, with deviations of less than 1% compared to estimates obtained through numerical simulations. Insights derived from this study can significantly contribute to the assessment of strategic decisions for utilizing depleted gas reservoirs for hydrogen storage.

Despite the great interest in thermochemical processes for converting plastic waste into chemical feedstocks or fuels, their kinetics are still a less studied topic, especially under reductive conditions. In the present work, non-isothermal thermogravimetric analysis is used to study the thermal and catalytic conversion of HDPE promoted by parent and metal-based H-USY (15) and H-ZSM-5 (11.5) zeolites under a reducing hydrogen atmosphere. Additionally, the respective kinetic parameters (apparent activation energy, Ea, and frequency factor, A) were determined by applying two distinct model-free methods: Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS). The results showed that Ea of the thermal degradation of HDPE has an average value of 227 kJ/mol for both methods. In the presence of H-USY (15) and H-ZSM-5 (11.5) zeolites, Ea is strongly reduced and is highly dependent on conversion. In the case of H-USY (15), Ea varies from 78 to 157 kJ/mol for the KAS method and from 83 to 172 kJ/mol for the FWO method. Slightly lower values are reported for H-ZSM-5, with Ea values in the range of 53–122 kJ/mol for KAS and 61–107 kJ/mol for FWO. The presence and type of the metal source (Ni, Pt, or Pd) also affect the kinetic parameters of the reaction. The mean Ea values follow the order: Ni > Pt ≈ Pd for H-USY (15) or H-ZSM-5 zeolites. Accordingly, both parent and metal-based H-USY (15) and H-ZSM-5 zeolites can significantly reduce energy consumption in HDPE hydrocracking, thus promoting a more sustainable conversion of plastic waste.

Self-assembled peptide-based hydrogels have attracted considerable interest from the research community. Particularly, low molecular weight gelators (LMWGs) consisting of amino acids and short peptides are highly suitable for biological applications owing to their facile synthesis and scalability, as well as their biocompatibility, biodegradability, and stability in physiological conditions. However, challenges in understanding the structure–property relationship and lack of design rules hinder the development of new gelators with the required properties for several applications. Hereby, in the plethora of peptide-based gelators, this review discusses the mechanical properties of single amino acid and dipeptide-based hydrogels. A mutual analysis of these systems allows us to highlight the relationship between the gel mechanical properties and amino acid sequence, preparation methods, or N capping groups. Additionally, recent advancements in the tuning of the gels’ rheological properties are reviewed. In this way, the present review aims to help bridge the knowledge gap between structure and mechanical properties, easing the selection or design of peptides with the required properties for biological applications.

The global burden of liver cancer is increasing. Timely diagnosis is important for optimising the limited available treatment options. Understanding the metabolic consequences of hepatocellular carcinoma (HCC) may lead to more effective treatment options. We aimed to document metabolite differences between HCC and matched surrounding tissues of varying aetiology, obtained at the time of liver resection, and to interpret metabolite changes with clinical findings. High-resolution magic angle spinning nuclear magnetic resonance (HRMAS-NMR) spectroscopy analyses of N = 10 paired HCC and surrounding non-tumour liver tissue samples were undertaken. There were marked HRMAS-NMR differences in lipid levels in HCC tissue compared to matched surrounding tissue and more subtle changes in low-molecular-weight metabolites, particularly when adjusting for patient-specific variability. Differences in lipid-CH3, lipid-CH2, formate, and acetate levels were of particular interest. The obvious differences in lipid content highlight the intricate interplay between metabolic adaptations and cancer cell survival in the complex microenvironment of liver cancer. Differences in formate and acetate might relate to bacterial metabolites. Therefore, documentation of metabolites in HCC tissue according to histology findings in patients is of interest for personalised medicine approaches and for tailoring targeted treatment strategies.

3,4-Methylenedioxypyrovalerone (MDPV) is an emerging, chiral, new psychoactive substance belonging to the synthetic cathinones group that has been frequently detected in wastewater effluents and aquatic environments. However, the knowledge of its enantioselective occurrence and toxicity toward aquatic organisms is scarce. The aim of this work was to develop an enantioselective liquid chromatography (LC) method to monitor the enantiomers of MDPV in environmental and ecotoxicological assays. For that, different chiral columns and mobile phases in both normal and reversed elution modes were attempted. The optimized conditions were achieved using a Daicel® 3 μm—CHIRALPAK® IF-3 column with 5 mM of ammonium bicarbonate (NH4HCO3, pH 8.8) in ultra-pure water (UPW) and acetonitrile (ACN) (10:90, v/v) as a mobile phase, at a flow rate of 0.3 mL min−1. This condition was applied to monitor the racemate and the single enantiomers of MDPV in culture medium collected from ecotoxicity experiments. Racemization was observed for MDPV enantiomers (in individual exposure). The enantiomeric ratio (e.r.) of (S)-MDPV changed from an initial e.r. of 96.4/3.6 to 78.0/22.0 and for the (R)-enantiomer, the e.r changed from 15.6/84.4 to 28.3/71.7). These data highlight the importance of enantioselective monitoring of culture media in toxicity assays that involve chiral substances, since racemization can occur and lead to inaccuracy in the toxicity evaluation. Nevertheless, it is also important to stress that racemization may occur during storage conditions or sample procedures. Therefore, the enantioselective methodology is of utmost importance to warrant the quality of the results in enantioselective ecotoxicological studies.

Despite its limitations, 2D kinematical analysis remains a simple and valid alternative for swimming analysis. This analysis is limited by the length of the field of view, and the reconstruction errors are proportional to the calibrated area. A possible solution for these problems is the usage of moving cameras that allow for tracking an object across a larger area without the concerns of the calibration area. The purpose of this study was to verify the viability of the utilization of moving cameras for underwater 2D kinematical analysis. Two calibration processes were evaluated: (i) obtaining the extrinsic parameters for every frame based on pool markers (M1) and; (ii) constraining the degrees of freedom of the camera’s movements and tracking translation based on the principal point (M2). M1 obtained better accuracy in reconstructing the coordinates of static markers (mean error: 12.1 against 14.2 mm from a static camera) and in the estimation of the rod length (−2.6 vs. 12.6 mm). M2 obtained better accuracy when evaluating the distance between the points (−0.3 mm) than that for position estimation (58.6 mm). The results indicate that moving cameras are a viable alternative for 2D underwater kinematic analysis, but M2 had limitations about real position extraction.

This study aimed to determine the total contents of copper, iron, and zinc in camapu and protein fractions by inductively coupled plasma emission spectrometry. Firstly, lipid removal was performed using chloroform and methanol (2:1). Protein fractions were obtained after sequential extraction using four extractors (water, 0.5 mol L-1 sodium chloride, 50% acetic acid v v-1 and 0.05 mol L-1 sodium hydroxide). The camapu sample and protein fractions were digested in a cavity-microwave oven with diluted nitric acid and hydrogen peroxide. The accuracy of the procedure was evaluated using the addition and recovery method in the digests and protein extracts. All the elements were determined in the protein fractions. Levels of Cu, Fe, and Zn ranged from 0.07 to 0.5 mg kg-1 were found in the lipid fraction. The residue presented higher iron content compared to other elements. Higher Cu and Zn contents were found associated with albumin. All elements studied were found in the protein fractions, and the total protein concentration determined in each protein fraction was 5.74 mg kg-1 (albumins), 0.28 mg kg-1 (globulins), 4.46 mg kg-1 (glutelins 1) and 0.46 mg kg-1 (glutelins 2).

The present study investigated the sources of variability in the water quality of surface springs that supply the Metropolitan Region of Belém (Pará, Brazil), as well as the treated water produced by the main water treatment station in the region. Data provided by Companhia de Saneamento do Pará were used, referring to physical-chemical and bacteriological analyzes carried out in the period from 2010 to 2020. In addition, precipitation data were considered in this study, in units of mm of rain, obtained by consulting the database of the National Institute of Meteorology. The application of principal component analysis, as an exploratory data analysis tool, allowed the grouping of the most relevant parameters of the results and proved to be efficient in reducing the data set, explaining more than 65% of the total variance, in all objects of study. Thus, it was possible to observe a general profile of the quality of surface water investigated, and, in this way, demonstrate the impact of urban pressure on the environment, as well as the need for maintenance and conservation of surface water resources.