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We compared the mental health of higher education students with that of nonstudents. Moreover, we examined whether the mental health of students predicts their probability of obtaining a higher education degree, and whether the extent to which mental health affects educational attainment varies by gender. Drawing on a risk and resilience framework, we considered five facets of mental health that may be implicated in distinct ways in the educational attainment process: positive attitude towards life, self-esteem, self-efficacy, negative affectivity, and perceived stress. We used data from a nationally representative panel study from Switzerland (Nstudents= 2070, 42.8% male; Nnonstudents= 3755, 45.9% male). The findings suggest that overall, the mental health of higher education students was relatively similar to that of nonstudents, although students exhibited slightly higher self-esteem, slightly weaker self-efficacy, greater negative affectivity, and higher levels of perceived stress. The effects of different facets of mental health on higher education degree attainment were mostly statistically and/or practically insignificant. However, positive attitudes towards life had a substantial positive effect on the probability of being awarded a higher education degree. Mental health was equally important for male and female students’ educational attainment.

An in vivo study was performed in order to evaluate the depletion time of stanozolol and its main metabolites using naturally incurred urine sample collected after the administration of intramuscular injections in 12 steers. A stability study was also carried out to investigate the influence of the storage period and the freeze–thaw cycles. A fast parent drug metabolization was observed, because within 6 h after drug administration, the signal of the metabolite 16β-hydroxystanozolol was predominant. After the second drug administration, a detection window of 17 days was obtained. The stability was studied using ANOVA, in which a storage condition of −20 °C proved stable during 240 days, which was also confirmed after 5 freeze–thaw cycles.

In this work, 37 growth promoters were quantitatively determined in bovine urine using a QuEChERS approach with acetonitrile, NaCl, and MgSO4:PSA for sample extraction. The analytes were separated and detected by liquid chromatography coupled to hybrid high-resolution mass spectrometry. The method was validated in accordance with the Decision 657/2002/EC guidelines, in which recoveries fell within the range 84–113%, relative standard varied between 2 and 32%, and detection limit between 0.1 and 2.5 μg L–1. An adequate performance was evidenced during a proficiency test evaluation, and the developed method has been applied to routine analysis of growth promoters in Brazil. A highlight is the easiness of sample extraction combined with a quantitative determination of forbidden drugs using high-resolution mass spectrometry, which enables retrospective analysis in a surveillance perspective.

This work involved a systematic comparison between serum and urine for the monitoring of anabolic androgenic steroids in livestock. Incurred samples were collected over 120 days from crossbred steers treated with intramuscular injections containing boldenone undecylenate. Independent high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) methods were used for the assessment of the respective detection windows, which were larger for serum samples. Both matrices presented adequate performance in terms of long-term stability, assessed using an isochronous approach during 196 days at −20 °C and for five freeze–thaw cycles. The effectiveness of the enzymatic hydrolysis reaction using Helix pomatiajuice was also compared. The calculated concentrations in serum samples were not statistically influenced by the deconjugation reaction. On the other hand, urine hydrolysis conditions were studied using a 33Box–Behnken Design, in which a central point condition led to a satisfactory deconjugation performance. It could be observed that serum exhibited equivalent or better performance than urine for most of the evaluated criteria; thus, its inclusion in the regulatory analysis of boldenone in cattle is supported.

Conventional in vitro propagation may affect normal morphophysiological characteristics and survival during the acclimatization of commercial plants, such as Etlingera Elatior(Jack) R.M. Smith. CO2enrichment, gas-permeable membranes, and reduced carbohydrate concentration in culture media can be used to mitigate these effects. Here, we aimed to determine the impact of photomixotrophic and photoautotrophic growth on morphophysiological responses of E. elatiorand its survival during ex vitro acclimatization. In vitro-established plants were placed in flasks containing semisolid MS medium with 0.54 µM α-naphthalene acetic acid and sucrose (0 or 15 g L−1). The flasks were sealed with lids with or without orifices covered by gas-permeable membranes and kept for 45 days under forced-air ventilation (360 or 1000 µmol−1CO2). Growth variables, anatomical and physiological characteristics, and survival rate were evaluated. Overall, 1000 µmol mol−1CO2, gas-permeable membranes, and 15 g L−1sucrose resulted in plants with higher fresh and dry mass, higher level of photosynthetic pigments, as well as more developed secondary ribs in the leaves, prominent midribs, highly organized and differentiated chlorenchyma cells (palisade and spongy parenchyma), more developed vascular bundles, and intercellular gaps were reduced, compared to conventionally in vitro-propagated plants. Moreover, these conditions promote morphophysiological responses and favored survival of E. elatiorplants (75%) when transferred to ex vitro conditions.

Serum analysis has received much attention in regulatory analysis of food-producing animals, especially for anabolic steroids. The possibility of confirming the parent drugs with minimum metabolization enables the detection of intact steroid esters, whose identification represents unequivocal proof of drug administration. This work involved the development and validation of a quantitative LC-MS/MS method to determine 30 steroids and steroid esters in bovine serum. Sensitivity was improved using microwave-assisted chemical derivatization with methoxyamine hydrochloride. The validation was successfully conducted in accordance with the Decision 657/2002/EC guidelines. An in vivo experiment was performed on 12 crossbred steers in which two commercial formulations containing boldenone undecylenate and testosterone propionate were administrated via intramuscular injections. The samples were collected over a period of 120 days, in which both intact esters were identified within 11 days postadministration. 17β-Boldenone was observed after 92 days for 2 steers and 56 days for the other animals. The applicability of a cut-off level to the ratio between 17β-testosterone and epitestosterone was evaluated in an attempt to differentiate testosterone abuse from endogenous production. It could be observed that a calculated ratio above this level is strong evidence of drug administration, although a high false-negative rate was obtained.

Herein, we report a complete additively manufactured (AM) electrochemical sensing platform. In this approach, a fully AM/3D-printed electrochemical system, using a conventional low-cost 3D printer (fused deposition modeling) fabricating both the conductive electrodes and the nonconductive/chemically inert electrochemical cell is reported. The electrodes (working, counter, and pseudo-reference) are AM using a conductive fused-filament comprised of a mixture of carbon black nanoparticles and polylactic acid (CB/PLA). AM components partially coated with silver ink presented a similar behavior to a conventional Ag/AgCl reference electrode. The performance of the AM working electrode was evaluated after a simple and fast polishing procedure on sandpaper and electrochemical activation in a NaOH solution (0.5 mol L–1). Following the electrochemical activation step, a considerable improvement in the electrochemical behavior (current intensity and voltammetric profile) was obtained for model analytes, such as dopamine, hexaammineruthenium(III) chloride, ferricyanide/ferrocyanide, uric acid, and ascorbic acid. Excellent repeatability (RSD = 0.4%, N= 10) and limit of detection (0.1 μmol L–1) were obtained with the all complete AM electrochemical system for dopamine analysis. The electrochemical performance of the developed system (after simple electrochemical activation of the working electrode) was similar or better than those obtained using commercial glassy carbon and screen-printed carbon electrodes. The results shown here represents a significant advance in AM (3D printing) technology for analytical chemistry.

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. In the northern region of Brazil, this disease is caused by Cryptococcus neoformansgenotype VNI and Cryptococcus gattiigenotype VGII. However, few environmental studies have been conducted in this large tropical area. This study was performed to isolate, genotype, and determine the frequency of cryptococcal agents in environmental samples near Manaus, Amazonas, Brazil. A total of 970 environmental samples (290 from soil, 290 from decaying plants, 5 from insects, 280 from the Negro river, and 105 from small streams within the city of Manaus) were collected and plated on Niger seed agar. In addition, 20 sub-cultures obtained from each positive sample were analyzed by PCR-RFLP (URA5) and PCR for genotyping and determination of mating type. Six samples were positive for isolates from the C. gattiispecies complex. Of those, three samples were from Adolpho Ducke Forest Reserve and three were from the Negro river. All isolates were C. gattiigenotype VGII (mating type MATα). Genotype VGII proved to be the most important genotype found in the environmental samples. The genotype VGII has been described as one of the most virulent and less susceptible to antifungals and responsible for important outbreaks. This is the first study to demonstrate isolation of C. gattii(VGII) from the Negro river.

In this work, a GC-MS/MS method was developed for the determination of anabolic-agent residues in bovine urine. The optimized sample preparation was as follows: enzymatic hydrolysis by β-glucuronidase–sulfatase enzyme from Helix pomatiafor 16 h at 37.5 °C, liquid–liquid extraction with diethyl ether, solid-phase extraction with HLB and aminopropylsilane cartridges, and microwave-assisted derivatization using 25 μL of MSTFA/NH4I/ethanethiol and full microwave power for 2 min. The method was validated according to Decision 657/2002/EC, Codex Alimentarius, and Manual da Garantia da Qualidade Analítica guidelines. The acceptability criteria for quantitative analysis were met for α-ethinylestradiol, α-nandrolone, β-estradiol, β-zearalanol, β-zearalenol, drostanolone, ethisterone, dienestrol, diethylstilbestrol, hexestrol, megestrol, methyltestosterone, and zearalenone. The analytes α-zearalenol, α-zearalanol, and norethandrolone were validated for qualitative analysis.

Forensic chemistry is the application of analytical chemistry to forensic analysis and is today one of the hot topics in the scientific literature as it can provide valuable information regarding crimes that have been committed and assist in their resolution. The literature in the field of forensic chemistry has been exponentially growing and covers several different subjects. This review discusses works published between 2013 and 2017 regarding portable or potentially portable devices (such as electrochemical sensors), field tests and intelligent devices that can be used in different areas of forensic chemistry and covers the following subjects: explosives, gunshot residues (GSR), liquid fuels, illicit drugs, beverages, alternative biological fluids and agrochemicals.

A reliable method using a QuEChERS approach and liquid chromatography coupled to Q-Orbitrap mass spectrometry was optimized and validated for the quantification of 20 growth promoters in bovine serum. The recoveries ranged from 91.4–114.1%, relative standard deviations varied between 0.3–4.0%, and CCα values were between 0.023–0.350 μg L–1. The developed method was applied in an in vivostudy using steers, which were intramuscularly treated with commercial injections containing stanozolol. A rapid metabolization was observed, with a detection window ranging from 3 to 10 days. The stability of incurred stanozolol was confirmed after 240 days at −20 °C and also after 5 freeze–thaw cycles. To the best of our knowledge, this is the first work in which an in vivostudy was performed to support the monitoring of stanozolol in bovine serum. In addition, the use of Q-Orbitrap high-resolution mass spectrometry allows for retrospective analysis from a surveillance perspective.

The 3D printing (or additive manufacturing, AM) technology is capable to provide a quick and easy production of objects with freedom of design, reducing waste generation. Among the AM techniques, fused deposition modeling (FDM) has been highlighted due to its affordability, scalability, and possibility of processing an extensive range of materials (thermoplastics, composites, biobased materials, etc.). The possibility of obtaining electrochemical cells, arrays, pieces, and more recently, electrodes, exactly according to the demand, in varied shapes and sizes, and employing the desired materials has made from 3D printing technology an indispensable tool in electroanalysis. In this regard, the obtention of an FDM 3D printer has great advantages for electroanalytical laboratories, and its use is relatively simple. Some care has to be taken to aid the user to take advantage of the great potential of this technology, avoiding problems such as solution leakages, very common in 3D printed cells, providing well-sealed objects, with high quality. In this sense, herein, we present a complete protocol regarding the use of FDM 3D printers for the fabrication of complete electrochemical systems, including (bio)sensors, and how to improve the quality of the obtained systems. A guide from the initial printing stages, regarding the design and structure obtention, to the final application, including the improvement of obtained 3D printed electrodes for different purposes, is provided here. Thus, this protocol can provide great perspectives and alternatives for 3D printing in electroanalysis and aid the user to understand and solve several problems with the use of this technology in this field.

Abstract: Hyperinsulinemia in obesity has been attributed to insulin oversecretion by pancreatic beta-cells. Beta-cells are equipped with cholinergic and adrenergic receptors; whereas overall acetylcholine action is to potentiate, catecholamines' effect is to inhibit glucoseinduced insulin release (GIIR) via α2-adrenoreceptor. However, it has been shown that \-adrenergic agonists potentiate glucose response. GIIR was studied in pancreatic islets from hyperinsulinemic adult obese rats, obtained by l-glutamate monosodium (MSG) neonatal treatment. Islets from MSG-rats were more glucose responsive than control ones. Isoproterenol, a \-adrenergic agonist, inhibited the GIIR in islets from MSG-obese rats. Results indicate that MSG treatment causes alteration on function of beta-cell adrenoceptors.