Luminescent Supramolecular Metallogels: Drug Loading and Eu(III) as Structural Probe.

Supramolecular metallogels combine the rheological properties of gels with the color, magnetism, and other properties of metal ions. Lanthanide ions such as Eu(III) can be valuable components of metallogels due to their fascinating luminescence. In this work, we combine Eu(III) and iminodiacetic acid (IDA) into luminescent hydrogels. We investigate the tailoring of the rheological properties of these gels by changes in their metal:ligand ratio. Further, we use the highly sensitive Eu(III) luminescence to obtain information about the chemical structure of the materials. In special, we take advantage of computational calculations to employ an indirect method for structural elucidation, in which the simulated luminescent properties of candidate structures are matched to the experimental data. With this strategy, we can propose molecular structures for different EuIDA gels. We also explore the usage of these gels for the loading of bioactive molecules such as OXA, observing that its aldose reductase activity remains present in the gel. We envision that the findings from this work could inspire the development of luminescent hydrogels with tunable rheology for applications such as 3D printing and imaging-guided drug delivery platforms. Finally, Eu(III) emission-based structural elucidation could be a powerful tool in the characterization of advanced materials.

Antipsychotic agents in anxiety disorders: An umbrella review.

BACKGROUND: Although not approved for the treatment of anxiety disorders (except trifluoperazine) there is ongoing off-label, unapproved use of first-generation antipsychotics (FGAs) and second-generation antipsychotics (SGAs) for anxiety disorders. There have been systematic reviews and meta-analyses on the use of antipsychotics in anxiety disorders, most of which focused on SGAs. OBJECTIVE: The specific aims of this umbrella review are to: (1) Evaluate the evidence of efficacy of FGAs and SGAs in anxiety disorders as an adjunctive treatment to traditional antidepressant treatments and other nonantipsychotic medications; (2) Compare monotherapy with antipsychotics to first-line treatments for anxiety disorders in terms of effectiveness, risks, and side effects. The review protocol is registered on PROSPERO (CRD42021237436). METHODS: An initial search was undertaken to identify systematic reviews and meta-analyses from inception until 2020, with an updated search completed August 2021 and January 2023. The searches were conducted in PubMed, MEDLINE (Ovid), EMBASE (Ovid), APA PsycInfo (Ovid), CINAHL Complete (EBSCOhost), and the Cochrane Library through hand searches of references of included articles. Review quality was measured using the AMSTAR-2 (A MeaSurement Tool to Assess Systematic Reviews) scale. RESULTS: The original and updated searches yielded 1796 and 3744 articles respectively, of which 45 were eligible. After final review, 25 systematic reviews and meta-analyses were included in the analysis. Most of the systematic reviews and meta-analyses were deemed low-quality through AMSTAR-2 with only one review being deemed high-quality. In evaluating the monotherapies with antipsychotics compared with first-line treatments for anxiety disorder there was insufficient evidence due to flawed study designs (such as problems with randomization) and small sample sizes within studies. There was limited evidence suggesting efficacy of antipsychotic agents in anxiety disorders other than quetiapine in generalized anxiety disorder (GAD). CONCLUSIONS: This umbrella review indicates a lack of high-quality studies of antipsychotics in anxiety disorders outside of the use of quetiapine in GAD. Although potentially effective for anxiety disorders, FGAs and SGAs may have risks and side effects that outweigh their efficacy, although there were limited data. Further long-term and larger-scale studies of antipsychotics in anxiety disorders are needed.

Substrate suppression of oxidation process in pnictogen monolayers.

2D materials present an interesting platform for device designs. However, oxidation can drastically change the system's properties, which need to be accounted for. Through ab initio calculations, we investigated freestanding and SiC-supported As, Sb, and Bi mono-elemental layers. The oxidation process occurs through an O2 spin-state transition, accounted for within the Landau-Zener transition. Additionally, we have investigated the oxidation barriers and the role of spin-orbit coupling. Our calculations pointed out that the presence of SiC substrate reduces the oxidation time scale compared to a freestanding monolayer. We have extracted the energy barrier transition, compatible with our spin-transition analysis. Besides, spin-orbit coupling is relevant to the oxidation mechanisms and alters time scales. The energy barriers decrease as the pnictogen changes from As to Sb to Bi for the freestanding systems, while for SiC-supported, they increase across the pnictogen family. Our computed energy barriers confirm the enhanced robustness against oxidation for the SiC-supported systems.

Dexmedetomidine in the Treatment of Depression: An Up-to-date Narrative Review.

Depressive disorders (DD) are common, and their prevalence is expected to rise over the next decade. Depressive disorders are linked to significant morbidity and mortality. The clinical conundrum of depressive disorders lies in the heterogeneity of their phenomenology and etiology. Further, the currently available antidepressants have several limitations, including a delayed onset of action, limited efficacy, and an unfavorable side effect profile. In this review, Dexmedetomidine (DEX), a highly selective and potent α2-adrenergic receptor (α2-AR) agonist, is proposed as a potentially novel antidepressant with multiple mechanisms of action targeting various depression pathophysiological processes. These mechanisms include modulation of the noradrenergic system, regulation of neuroinflammation and oxidative stress, influence on the Brain-Derived Neurotrophic Factor (BDNF) levels, and modulation of neurotransmitter systems, such as glutamate. The review begins with an introduction before moving on to a discussion of DEX's pharmacological features. The pathophysiological and phenomenological targets of DD are also explored, along with the review of the existing preclinical and clinical evidence for DEX's putative anti-depressant effects. Finally, the review ends by presenting the pertinent conclusions and future directions.

Donor-Acceptor Stenhouse Adduct-Polydimethylsiloxane-Conjugates for Enhanced Photoswitching in Bulk Polymers.

Donor-acceptor Stenhouse adducts (DASAs) are a rapidly emerging class of visible light-activated photochromes and DASA-functionalized polymers hold great promise as biocompatible photoresponsive materials. However, the photoswitching performance of DASAs in solid polymer matrices is often low, particularly in materials below their glass transition temperature. To overcome this limitation, DASAs are conjugated to polydimethylsiloxanes which have a glass transition temperature far below room temperature and which can create a mobile molecular environment around the DASAs for achieving more solution-like photoswitching kinetics in bulk polymers. The dispersion of DASAs conjugated to such flexible oligomers into solid polymer matrices allows for more effective and tunable DASA photoswitching in stiff polymers, such as poly(methyl methacrylate), without requiring modifications of the matrix. The photoswitching of conjugates with varying polymer molecular weight, linker type, and architecture is characterized via time-dependent UV-vis spectroscopy in organic solvents and blended into polymethacrylate films. In addition, DASA-functionalized polydimethylsiloxane networks, accessible via the same synthetic route, provide an alternative solution for achieving fast and efficient DASA photoswitching in the bulk owing to their intrinsic softness and flexibility. These findings may contribute to the development of DASA-functionalized materials with better tunable, more effective, and more reversible modulation of their optical properties.

Quantitative GC-TCD Measurements of Major Flatus Components: A Preliminary Analysis of the Diet Effect.

The impact of diet and digestive disorders in flatus composition remains largely unexplored. This is partially due to the lack of standardized sampling collection methods, and the easy atmospheric contamination. This paper describes a method to quantitatively determine the major gases in flatus and their application in a nutritional intervention. We describe how to direct sample flatus into Tedlar bags, and simultaneous analysis by gas chromatography-thermal conductivity detection (GC-TCD). Results are analyzed by univariate hypothesis testing and by multilevel principal component analysis. The reported methodology allows simultaneous determination of the five major gases with root mean measurement errors of 0.8% for oxygen (O2), 0.9% for nitrogen (N2), 0.14% for carbon dioxide (CO2), 0.11% for methane (CH4), and 0.26% for hydrogen (H2). The atmospheric contamination was limited to 0.86 (95% CI: [0.7-1.0])% for oxygen and 3.4 (95% CI: [1.4-5.3])% for nitrogen. As an illustration, the method has been successfully applied to measure the response to a nutritional intervention in a reduced crossover study in healthy subjects.

Do parasites influence behavioural traits of wild and hatchery-reared Murray cod, Maccullochella peelii?

This study aimed to investigate the links between parasites and behavioural traits of juvenile Murray cod (Maccullochella peelii). The Murray cod is an endangered Australian freshwater fish for which restocking programs are in place and there is a growing human consumption market. However, little is known about the parasites of these fish and how these parasites influence their behaviour and survival. Fingerlings and yearling fish were sourced from a hatchery and the wild, and after acclimatisation in the laboratory, variation in behavioural traits was examined using emergence, exploration and predator inspection tests. The fish were then euthanised to determine their age and examined for infection with parasites. Wild fish had more camallanid nematodes and lernaeid copepods than hatchery fish. An information theoretic approach using Akaike's Information Criterion (AIC) indicated that infection with protozoan cysts was an important factor for predicting the latency to emerge and explore a new environment, which was interpreted as reduced "boldness". In contrast, the presence of lernaeid copepods was included in two of the four best models predicting predator inspection, indicating that infected fish were less likely to inspect a predator. Source of fish (wild or hatchery) was found to be a strong influence on behavioural responses in all our tests. All parasites found in the present study are known to result in clinical signs of diseases in their fish hosts, raising the possibility that responses in tests of behavioural traits reflect side effects of infection. Additionally, the effect of host adaptation to not show signs of parasite infection, or more simply that the effects on behaviour are subtle and difficult to reveal with small sample sizes, is discussed. Nonetheless, we propose that it is important that infection with parasites is considered in fish behavioural studies both to assess survival behaviour and to avoid misinterpretation of behavioural tests of animal personality.

Full Workflows for the Analysis of Gas Chromatography-Ion Mobility Spectrometry in Foodomics: Application to the Analysis of Iberian Ham Aroma.

Gas chromatography-ion mobility spectrometry (GC-IMS) allows the fast, reliable, and inexpensive chemical composition analysis of volatile mixtures. This sensing technology has been successfully employed in food science to determine food origin, freshness and preventing alimentary fraud. However, GC-IMS data is highly dimensional, complex, and suffers from strong non-linearities, baseline problems, misalignments, peak overlaps, long peak tails, etc., all of which must be corrected to properly extract the relevant features from samples. In this work, a pipeline for signal pre-processing, followed by four different approaches for feature extraction in GC-IMS data, is presented. More precisely, these approaches consist of extracting data features from: (1) the total area of the reactant ion peak chromatogram (RIC); (2) the full RIC response; (3) the unfolded sample matrix; and (4) the ion peak volumes. The resulting pipelines for data processing were applied to a dataset consisting of two different quality class Iberian ham samples, based on their feeding regime. The ability to infer chemical information from samples was tested by comparing the classification results obtained from partial least-squares discriminant analysis (PLS-DA) and the samples' variable importance for projection (VIP) scores. The choice of a feature extraction strategy is a trade-off between the amount of chemical information that is preserved, and the computational effort required to generate the data models.

Flavin-Containing Monooxygenase 1 Catalyzes the Production of Taurine from Hypotaurine.

Taurine is one of the most abundant amino acids in mammalian tissues. It is obtained from the diet and by de novo synthesis from cysteic acid or hypotaurine. Despite the discovery in 1954 that the oxygenation of hypotaurine produces taurine, the identification of an enzyme catalyzing this reaction has remained elusive. In large part, this is due to the incorrect assignment, in 1962, of the enzyme as an NAD-dependent hypotaurine dehydrogenase. For more than 55 years, the literature has continued to refer to this enzyme as such. Here we show, both in vivo and in vitro, that the enzyme that oxygenates hypotaurine to produce taurine is flavin-containing monooxygenase (FMO) 1. Metabolite analysis of the urine of Fmo1-null mice by 1H NMR spectroscopy revealed a buildup of hypotaurine and a deficit of taurine in comparison with the concentrations of these compounds in the urine of wild-type mice. In vitro assays confirmed that human FMO1 catalyzes the conversion of hypotaurine to taurine, utilizing either NADPH or NADH as cofactor. FMO1 has a wide substrate range and is best known as a xenobiotic- or drug-metabolizing enzyme. The identification that the endogenous molecule hypotaurine is a substrate for the FMO1-catalyzed production of taurine resolves a long-standing mystery. This finding should help establish the role FMO1 plays in a range of biologic processes in which taurine or its deficiency is implicated, including conjugation of bile acids, neurotransmitter, antioxidant and anti-inflammatory functions, and the pathogenesis of obesity and skeletal muscle disorders. SIGNIFICANCE STATEMENT: The identity of the enzyme that catalyzes the biosynthesis of taurine from hypotaurine has remained elusive. Here we show, both in vivo and in vitro, that flavin-containing monooxygenase 1 catalyzes the oxygenation of hypotaurine to produce taurine.

Neurostimulation in Anxiety Disorders, Post-traumatic Stress Disorder, and Obsessive-Compulsive Disorder.

Many pharmacological treatments were proved effective in the treatment of panic disorder (PD), generalized anxiety disorder (GAD), social anxiety disorder (SAD), post-traumatic stress disorder (PTSD), and obsessive-compulsive disorder (OCD); still many patients do not achieve remission with these treatments. Neurostimulation techniques have been studied as promising alternatives or augmentation treatments to pharmacological and psychological therapies. The most studied neurostimulation method for anxiety disorders, PTSD, and OCD was repetitive transcranial magnetic stimulation (rTMS). This neurostimulation technique had the highest level of evidence for GAD. There were also randomized sham-controlled trials indicating that rTMS may be effective in the treatment of PTSD and OCD, but there were conflicting findings regarding these two disorders. There is indication that rTMS may be effective in the treatment of panic disorder, but the level of evidence is low. Deep brain stimulation (DBS) was most studied for treatment of OCD, but the randomized sham-controlled trials had mixed findings. Preliminary findings indicate that DBS could be affective for PTSD. There is weak evidence indicating that electroconvulsive therapy, transcranial direct current stimulation, vagus nerve stimulation, and trigeminal nerve stimulation could be effective in the treatment of anxiety disorders, PTSD, and OCD. Regarding these disorders, there is no support in the current literature for the use of neurostimulation in clinical practice. Large high-quality studies are warranted.

A Brazilian Case of Treatment-Resistant Generalized Anxiety Disorder Successfully Treated with Monoamine Oxidase Inhibitor (MAOI).

In this brief report we present the case of a 53 year old man with a very debilitating Generalized Anxiety Disorder successfully treated with tranylcypromine. After several failed treatment attempts following international guidelines recommendations over the course of one year and a half, tranylcypromine was prescribed which led to effective and sustained remission of anxiety symptoms for this patient. We also briefly explore treatment options for resistant cases of generalized anxiety disorder, given the major negative impacts of untreated GAD in a person's daily functioning and quality of life.

Identification of antiplasmodial triterpenes from Keetia species using NMR-based metabolic profiling.

INTRODUCTION: The increase in multidrug resistance and lack of efficacy in malaria therapy has propelled the urgent discovery of new antiplasmodial drugs, reviving the screening of secondary metabolites from traditional medicine. In plant metabolomics, NMR-based strategies are considered a golden method providing both a holistic view of the chemical profiles and a correlation between the metabolome and bioactivity, becoming a corner stone of drug development from natural products. OBJECTIVE: Create a multivariate model to identify antiplasmodial metabolites from 1H NMR data of two African medicinal plants, Keetia leucantha and K. venosa. METHODS: The extracts of twigs and leaves of Keetia species were measured by 1H NMR and the spectra were submitted to orthogonal partial least squares (OPLS) for antiplasmodial correlation. RESULTS: Unsupervised 1H NMR analysis showed that the effect of tissues was higher than species and that triterpenoids signals were more associated to Keetia twigs than leaves. OPLS-DA based on Keetia species correlated triterpene signals to K. leucantha, exhibiting a higher concentration of triterpenoids and phenylpropanoid-conjugated triterpenes than K. venosa. In vitro antiplasmodial correlation by OPLS, validated for all Keetia samples, revealed that phenylpropanoid-conjugated triterpenes were highly correlated to the bioactivity, while the acyclic squalene was found as the major metabolite in low bioactivity samples. CONCLUSION: NMR-based metabolomics combined with supervised multivariate data analysis is a powerful strategy for the identification of bioactive metabolites in plant extracts. Moreover, combination of statistical total correlation spectroscopy with 2D NMR allowed a detailed analysis of different triterpenes, overcoming the challenge posed by their structure similarity and coalescence in the aliphatic region.

Negative Affect Mediates Impulsivity in Generalized Anxiety Disorder.

INTRODUCTION: Although anxiety and impulsivity are intuitively thought to be inversely correlated, increased impulsivity has been associated both with generalized anxiety disorder (GAD) diagnosis and GAD symptoms in non-clinical samples. The emotional dysregulation model of GAD posits that patients experience more frequent and intense negative emotions while having poor regulatory control over emotional states and greater negative reactivity to their emotions. We hypothesized that poor regulatory control in the presence of negative emotions might explain the increased impulsivity found in GAD patients. In this study, we examined if negative affect mediates the relationship between GAD and impulsivity. METHODS: Thirty-four GAD patients and 35 healthy controls were included, and evaluated with measurements of impulsivity, negative and positive emotions, the severity of worrying and GAD symptoms, depression, and 5-factor personality traits. RESULTS: Global impulsivity scores and the attentional facet of impulsivity were higher in the patient group when compared to the controls. Negative affect was correlated with global impulsivity in the patient group only and explained impulsivity in our regression model while worrying and depressive symptoms did not. An indirect relationship was found between diagnosis and impulsivity through negative affect. CONCLUSION: Our study showed that the cardinal symptom of GAD - worrying - was not independently related to impulsivity in our sample. Increased impulsivity in GAD seems to be mediated by the increased presence of negative emotions, as it is common in mood and impulse-control disorders, indicating an unspecific shared vulnerability factor to psychopathology.

Improvement of bioactive metabolite production in microbial cultures-A systems approach by OSMAC and deconvolution-based 1 HNMR quantification.

Traditionally, the screening of metabolites in microbial matrices is performed by monocultures. Nonetheless, the absence of biotic and abiotic interactions generally observed in nature still limit the chemical diversity and leads to "poorer" chemical profiles. Nowadays, several methods have been developed to determine the conditions under which cryptic genes are activated, in an attempt to induce these silenced biosynthetic pathways. Among those, the one strain, many compounds (OSMAC) strategy has been applied to enhance metabolic production by a systematic variation of growth parameters. The complexity of the chemical profiles from OSMAC experiments has required increasingly robust and accurate techniques. In this sense, deconvolution-based 1 HNMR quantification have emerged as a promising methodology to decrease complexity and provide a comprehensive perspective for metabolomics studies. Our present work shows an integrated strategy for the increased production and rapid quantification of compounds from microbial sources. Specifically, an OSMAC design of experiments (DoE) was used to optimize the microbial production of bioactive fusaric acid, cytochalasin D and 3-nitropropionic acid, and Global Spectral Deconvolution (GSD)-based 1 HNMR quantification was carried out for their measurement. The results showed that OSMAC increased the production of the metabolites by up to 33% and that GSD was able to extract accurate NMR integrals even in heavily coalescence spectral regions. Moreover, GSD-1 HNMR quantification was reproducible for all species and exhibited validated results that were more selective and accurate than comparative methods. Overall, this strategy up-regulated important metabolites using a reduced number of experiments and provided fast analyte monitor directly in raw extracts.

Panic Disorder and Chronic Caffeine Use: A Case-control Study.

BACKGROUND: Acute administration of caffeine produces panic attacks in most Panic Disorder (PD) patients, but little is known about chronic caffeine use in these patients. OBJECTIVE: To assess caffeine use in patients with PD and to ascertain if caffeine consumption is associated with sociodemographic or clinical features. METHODS: 65 adults with PD and 66 healthy controls were included in the current study. Their caffeine intake within the previous week was quantified with a questionnaire and compared. Harmful caffeine use was defined as consumption above 400 mg/day of caffeine. We tested for correlations between caffeine intake, demographic and clinical features. RESULTS: Patients consumed significantly more caffeine than controls (P < 0.001). 14% (N = 9) of the PD patients made harmful use of caffeine. The use of caffeine-containing medications was observed in 40% (N = 26) of the PD patients and 6% (N = 4) of controls. Consumption of energy drinks was observed in 11% (N = 7) of PD patients and in none of the healthy subjects. Patients reported sleeping significantly less than controls (P < 0.001). In PD patients, caffeine consumption was not correlated with the presence of panic attacks or comorbidity with depression. The use of benzodiazepines or sedative medications was not correlated with caffeine intake. CONCLUSION: High caffeine consumption in PD patients could be explained by the development of tolerance with regular use of this substance. Subtypes of sensitive and non-sensitive PD patients could also explain why some of these patients are able to tolerate high doses of caffeine.

Australian and New Zealand Veterinary Students' Opinions on Animal Welfare and Ethical Issues Concerning Animal Use within Sport, Recreation, and Display.

Animals used for sport, recreation and display are highly visible and can divide community attitudes. The study of animal welfare and ethics (AWE) as part of veterinary education is important because it is the responsibility of veterinarians to use their scientific knowledge and skills to promote animal welfare in the context of community expectations. To explore the attitudes of veterinary students in Australia and New Zealand to AWE, a survey of the current cohort was undertaken. The survey aimed to reveal how veterinary students in Australia and New Zealand rate the importance of five selected AWE topics for Day One Competences in animals used in sport, recreation and display and to establish how veterinary students' priorities were associated with gender and stage of study. The response rate (n = 851) across the seven schools was just over 25%. Results indicated little variation on ratings for topics. The topics were ranked in the following order (most to least important): Pushing of animals to their physiologic/behavioral limits; ownership/responsibility; euthanasia; educating the public; and behavior, selection, and training for sport and recreation displays. In contrast to related studies, ratings were not associated with stage of study and there were few differences associated with gender. More females rated the pushing of animals to physiologic/behavioral limits as extremely important than did males ( p < .001). The role of veterinarians in advocating for and educating the public about the welfare of animals used in sport, recreation and display merits further discussion.

VETERINARY STUDENTS' OPINIONS ON THEIR REQUIRED COMPETENCE IN DEALING WITH WELFARE AND ETHICS ISSUES PERTAINING TO WILDLIFE.

The aim of this research was to determine what veterinary students in Australia and New Zealand consider important for animal welfare and ethics (AWE) competence when dealing with wildlife, and to determine how these priorities correlate with gender and stage of study. These students were asked to state their gender and stage of veterinary education and to rank the importance of six AWE topics: (1) "disaster preparedness," (2) "veterinarians' duties to wild animals," (3) "methods and justification for wild animal use" (e.g., harvesting/ hunting, wildlife parks), (4) "tensions between animal-welfare concerns and environmental concerns," (5) "the nature and status of semiowned animals," and (6) "euthanasia," pertaining to wildlife for competence on the first day after their graduation. Data were then analyzed. Of 3,320 students invited to participate, 556 responded to questions about animals in the wild. The AWE topic ranked as the most important was "veterinarians' duties to wild animals," followed by "euthanasia." Senior students ranked "euthanasia" as the most important topic. The rankings of "methods and justification for wild animal use" and "tension between animal welfare and environmental concerns" were significantly less important for students in the later years of study than for those in early years. Male respondents ranked "euthanasia" as more important than female respondents did, especially in later years of study. Senior veterinary students ranked "euthanasia" as the most important AWE topic for day one competency.

Tranylcypromine Plus Amitriptyline for Electroconvulsive Therapy-Resistant Depression: A Long-Term Study.

BACKGROUND: Few therapeutic options are available for patients with electroconvulsive therapy-resistant major depressive disorder (ECT-r MDD), leaving a substantial proportion of this population beyond treatment possibilities. The combination of monoamine oxidase inhibitors and tricyclic antidepressants could be a potential strategy for managing ECT-r MDD, and the specific association of amitriptyline and tranylcypromine may offer additional tolerability advantages. Although promising, in our knowledge, no studies have examined until now the effectiveness of this combination in ECT-r MDD. METHODS: We report a retrospective cohort of 31 patients with ECT-r MDD treated in an open-label fashion with the combination of amitriptyline and tranylcypromine. RESULTS: Overall, 80.6% of the sample met response criteria at the end of the first 12 weeks of treatment. Seventy-six percent (19 of 25) of the responders were followed for a mean of 9.37 ± 3.86 years. During this follow-up period, none of the patients had a recurring depressive episode. The combination was well tolerated, whereas minor adverse effects were common, and no severe or life-threatening events were reported throughout the study. CONCLUSIONS: These findings indicate that the combination tranylcypromine and amitriptyline is a potentially safe and effective candidate for future investigation in the treatment and long-term maintenance of ECT-r MDD.

Chitosan-magnetite nanocomposite as a sensing platform to bendiocarb determination.

A novel platform for carbamate-based pesticide quantification using a chitosan/magnetic iron oxide (Chit-Fe3O4) nanocomposite as a glassy carbon electrode (GCE) modifier is shown for an analytical methodology for determination of bendiocarb (BND). The BND oxidation signal using GCE/Chit-Fe3O4 compared with bare GCE was catalyzed, showing a 37.5% of current increase with the peak potential towards less positive values, showing method's increased sensitivity and selectivity. Using square-wave voltammetry (SWV), calibration curves for BND determination were obtained (n = 3), and calculated detection and quantification limits values were 2.09 × 10-6 mol L-1 (466.99 ppb) and 6.97 × 10-6 mol L-1 (1555.91 ppb), respectively. The proposed electroanalytical methodology was successfully applied for BND quantification in natural raw waters without any sample pretreatment, proving that the GCE/Chit-Fe3O4 modified electrode showed great potential for BND determination in complex samples. ᅟ Graphical abstract.

Exploring the use of alternatives to animals in undergraduate education in Australia.

The replacement, reduction and refinement of animal use in education is part of the regulatory legislation in Australia, and requires the use of alternatives to animals where appropriate. The aims of this study were: a) to explore the extent of the replacement of animals when teaching life sciences to Australian undergraduate students; b) to understand which alternative models were being used, and the learning objectives covered; and c) to gain some insight into the circumstances facilitating the use of alternatives to animals in education. An anonymous online survey, consisting of open and closed questions, was conducted among faculty members that used either animal or alternative models in their teaching. A total of 27 faculty members participated, from eight universities. Human anatomy and physiology had the highest number of survey participants who had replaced animals entirely with alternative models. These subjects also had the highest number of participants that were using animal models. According to the participants, most learning objectives were met effectively by both types of model. Participants who only used alternatives were influenced by ethical considerations significantly more than those who used animal models and alternatives. We concluded that, while some participants have replaced animals successfully, others in the same field are still employing them, and that there appears to be a range of barriers to the wider adoption of alternatives to animal use.