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The management of prosthetic joint infections is a complex and multilayered process that is additionally complicated by the formation of bacterial biofilm. Foreign material provides the ideal grounds for the development of an intricate matrix that hinders treatment and creates a difficult environment for antibiotics to act. Surgical intervention is often warranted but requires appropriate adjunctive therapy. Despite available guidelines, several aspects of antibiotic therapy with antibiofilm activity lack clear definition. Given the escalating challenges posed by antimicrobial resistance, extended treatment durations, and tolerance issues, it is essential to ensure that antimicrobials with antibiofilm activity are both potent and diverse. Evidence of biofilm-active drugs is highlighted, and alternatives to classical regimens are further discussed.

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Exercise increases peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α) expression, which in turn causes the fibronectin type III domain containing 5 (FNDC5) protein to be produced. This protein is then cleaved, primarily in skeletal muscle fibers, to produce irisin. When the mature FNDC5 is cleaved by proteases, Irisin - which is the fibronectin III domain without the signal sequence - is released. Resistance, aerobic, and high-intensity interval training (HIIT) are recognized as forms of physical exercise that raise irisin levels, and insulin receptor phosphorylation in tyrosine residues, favoring an increase in the activity of the insulin-dependent pathway (PI3K pathway) and assisting in the fight against insulin resistance, inflammation, and cognitive decline. Irisin may represent a promising option for the therapeutic targeting in several brain-related pathological conditions, like Alzheimer's disease (AD), Parkinson's disease (PD), epilepsy, type 2 diabetes, and obesity. Exercise protocols are healthy and inexpensive interventions that can help find cellular and molecular changes in several brain-related pathological conditions. Here, it was reviewed what is known about exercise-produced irisin studies involving AD, PD, epilepsy, type 2 diabetes, and obesity.

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Traumatic brain injury is a significant problem worldwide. In the United States of America, around 1.7 million cases are documented annually, displaying the need for a deeper understanding of the effects on the human brain. The tests required for this assessment are very complex. Tests on cadavers may raise serious ethical questions, and in vivo crash tests are not viable. In this context, there is a great need to developing finite element head models (FEHM) to study the biomechanics of the tissues when submitted to a certain impact or acceleration/deceleration scenario. An excellent compromise between accuracy and CPU efficiency is always desirable for a FEHM, For this reason, this work focuses on the improvement of an existing head model, including the study of the behavior of the brain using distinct finite element types. The finite element type and formulation is of utmost importance for the general accuracy and efficiency of the models. Several validations were performed, comparing the simulation results against experimental data. The simulations with hexahedral elements, under specific conditions, obtained more accurate results with a lower computational cost. Using hexahedrals, a comparison was also performed using two material characterizations with more than 10 years apart, using the latest finite element head model validation experiment. Overall, the newer material model displays a less stiff response, although its implementation must always depend on the overall purpose of the model it is being applied to.

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The aim of this study was to evaluate the effects of swimming in the brain and behavior of young and aged mice. Forty-eight male C57BL/6 J mice were randomly distributed into 4 groups (n = 12 per group, 3 and 18 months old). The subdivision of the groups was: 3 months-SED, 18 months-SED, 3 months-EXE, and 18 months-EXE. SED mice did not swim, while EXE mice performed the physical exercise protocol. Training was initiated 48 h after the adaptation week. Swimming sessions consisted of 30 min, with no overload, 5 days per week, for 4 weeks. After the exercise protocol, it was revealed working and spatial memory were impaired in the 18 months-SED group. Pre- and post-synaptic proteins were enhanced in the groups that swam when compared to the 3- and 8 months-SED groups. Lipid peroxidation was greater in the aged mice that did not perform the physical exercise protocol and might have contributed to the cognitive impairment in this group. In conclusion, an aerobic physical exercise protocol, performed through regular swimming sessions, inhibited cognitive impairment, memory loss and lipid peroxidation in the aged mice, while pre- and post-synaptic proteins were enhanced in the hippocampus of young and aged mice.

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This study aimed to compare the effects of High-Intensity Interval Training (HIIT) performed in a single session(1xHIIT) versus three daily sessions (3xHIIT) on fitness level and behavior of aged rats. Eighteen-month-old Wistar rats were assigned to Untrained (UN), 1xHIIT, or 3xHIIT (n = 12/group). Both groups, 1xHIIT and 3xHIIT, performed 15 min of a treadmill running HIIT protocol during 8 weeks. 1xHIIT protocol consisted of a single daily session of 15 min, while the 3xHIIT performed three daily sessions of 5 min with a 4 h interval between the sessions. Morris Water Maze (MWM) task was used to evaluate spatial learning and memory. Splash test, Forced Swim test, and Elevated Plus Maze task (EPM) were used to evaluate anhedonic, depressive-like, and anxious behaviors, respectively. Rats were euthanized, and the hippocampus was harvested for western blot analyses (CaMKII and BDNF). Both HIIT protocols improved VO2max and spatial memory. Notably, only the 3xHIIT protocol attenuated anxious and depressive-like behaviors. Western blot analyses of the hippocampus revealed that both HIIT protocols increased BDNF levels. BDNF levels were higher in the 3xHIIT when compared with 1xHIIT group, and we observed increasement of the CamKII levels just in the 3x HIIT group. Therefore, this study provides evidence indicating that accumulated HIIT sessions is more effective than traditional daily HIIT sessions in improving fitness level, cognitive function, memory, inhibiting the development of mood disorders, and enhancing BDNF and CaMKII levels in the hippocampus of aged rats.

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Escherichia coli is one of the key bacteria responsible for a variety of diseases in humans and livestock-associated infections around the globe. It is the leading cause of mortality in neonatal and weaned piglets in pig husbandry, causing diarrhea and significant harm to the industry. Furthermore, the frequent and intensive use of antimicrobials for the prevention of diseases, particularly gastrointestinal diseases, may promote the selection of multidrug-resistant (MDR) strains. These resistant genotypes can be transmitted through the excrement of animals, including swine. It is common practice to use porcine manure processed by biodigesters as fertilizer. This study aimed to examine the antimicrobial susceptibility, the presence of virulence genes frequently associated with pathotypes of intestinal pathogenic E. coli (InPEC), and antimicrobial resistance genes (ARGs) of 28 E. coli isolates collected from swine manure fertilizers. In addition, the enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) technique was used to investigate the genetic relationship among the strains. Using disk diffusion, the antimicrobial susceptibility profiles of the strains were determined. Using polymerase chain reaction (PCR), 14 distinct virulence genes associated with the most prevalent diarrhea and intestinal pathogenic E. coli (DEC/InPEC) and five ARGs were analyzed. All isolates tested positive for multidrug resistance. There was no detection of any of the 14 virulence genes associated with InPECs, indicating the presence of an avirulent commensal microbiota. Molecular classification by ERIC-PCR revealed that the majority of isolates (27 isolates) coalesced into a larger cluster with a genetic similarity of 47.7%; only one strain did not cluster in this cluster, indicating a high level of genetic diversity among the analyzed isolates. Thus, it is of the utmost importance to conduct epidemiological surveillance of animal breeding facilities in order to determine their microbiota and formulate plans to reduce the use of antimicrobials and improve animal welfare.

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Cork composites are byproducts from wine stopper production, resulting from the agglomeration of cork granules with a thermoset resin. The resulting compound is a versatile and durable material with numerous industrial applications. Due to its unique properties, such as low-density, high-strength, excellent energy absorption, and good thermal and acoustic insulators, cork composites find room for application in demanding industries such as automotive, construction, and aerospace. However, agglomerated cork typically has a polyurethane matrix derived from petrochemical sources. This study focuses on developing eco-friendly porous polyurethane biocomposites manufactured with the used cooking oil polyol modified with cork. Since cork and polyurethane foam are typically used for impact shock absorption, the manufactured samples were subjected to impact loading. The assessment of crashworthiness is performed through 100 J impact tests. A finite element numerical model was developed to simulate the compression of these new composites under impact, and the model validation was performed. The highest specific absorbed energy was obtained for petrochemical polyol composites with the 3% addition of natural or modified cork. The research conducted in this study showcased the feasibility of substituting certain petrochemical components used for the synthesis of the polyurethane matrix with ecological waste vegetable oil components.

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Magnetic skyrmions are topological spin textures which are envisioned as nanometer scale information carriers in magnetic memory and logic devices. The recent demonstrations of room temperature skyrmions and their current induced manipulation in ultrathin films were first steps toward the realization of such devices. However, important challenges remain regarding the electrical detection and the low-power nucleation of skyrmions, which are required for the read and write operations. Here, we demonstrate, using operando magnetic microscopy experiments, the electrical detection of a single magnetic skyrmion in a magnetic tunnel junction (MTJ) and its nucleation and annihilation by gate voltage via voltage control of magnetic anisotropy. The nucleated skyrmion can be manipulated by both gate voltages and external magnetic fields, leading to tunable intermediate resistance states. Our results unambiguously demonstrate the readout and voltage controlled write operations in a single MTJ device, which is a major milestone for low power skyrmion based technologies.

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This review analyzes the occurrence and co-exposure of aflatoxins and fumonisins in conventional and organic corn, and compares the vulnerability to contamination of both. The risks of fungal contamination in corn are real, mainly by the genera Aspergillus and Fusarium, producers of aflatoxins and fumonisins, respectively. Aflatoxins, especially AFB1, are related to a high incidence of liver cancer, and the International Agency Research of Cancer (IARC) classified them in group 1A 'carcinogenic to humans'. The occurrence in conventional corn is reported in many countries, including at higher levels than those established by legislation. IARC classified fumonisins in group 2B 'possibly carcinogenic to humans' due to their link with incidence of esophageal cancer. However, comparing corn and organic and conventional by-products from different regions, different results are observed. The co-occurrence of both mycotoxins is a worldwide problem; nevertheless, there is little data on the comparison of the co-exposure of these mycotoxins in corn and derivatives between both systems. It was found that the agricultural system is not a decisive factor in the final contamination, indicating the necessity of effective strategies to reduce contamination and co-exposure at levels that do not pose health risks.

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This study aimed to compare AFM1 occurrence in different cheese types produced by organic and conventional systems; and to evaluate the risk of food exposure to AFM1. A total of 176 commercial cheeses of 17 types were analyzed, 84 of organic and 92 of conventional production. Determination of AFM1 was performed by high- performance liquid chromatography (HPLC), being detected in 30.5% of samples, with 4.8% of organic cheese samples presenting quantifiable AFM1 values between 0.88 and 1.50 µg/kg. On the other hand, 4.3% of conventional cheese samples with values between 0.79 and 6.70 µg/kg. Two conventional cheese samples were above the limit of AFM1 allowed for cheeses by the Brazilian legislation. No statistical difference were found between organic and conventional cheeses regarding the occurrence (p = 0.1780) and concentration of AFM1 (p = 0.1810), according to the Chi-square and the T test, respectively. Estimated daily intake (EDI) and hazard index (HI) of dietary exposure to AFM1 were 0.26 ng/kg/day and 1.28 ng/kg/day, respectively, for conventional cheese samples, and 0.09 ng/kg/day and 0.47 ng/kg/day for organic samples, with no statistical difference for EDI (p = 0.1729) and HI (p = 0.1802) between the two production systems. Comparison between several cheese types from conventional and organic systems indicated that AFM1 is an obstacle to dairy production. Control and prevention of AFM1 contamination, as well as detoxification methods in the final products, are necessary. In the case of organic products, additional research is needed in order to determine which control and detoxification methods should be allowed in this production system.

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Arterial hypertension is a multifactorial clinical condition characterized by higher blood pressure levels. The main treatment for controlling high blood pressure consists of drug therapy, but the scientific literature has been pointing to the efficiency of aerobic and resistance exercises acting in a therapeutic and/or preventive way to reduce and control the blood pressure levels. Resistance training is characterized by sets and repetitions on a given muscle segment that uses overload, such as machine weights, bars, and dumbbells. As it successfully affects a number of variables associated to practitioners' functional and physiological features as well as emotional and social variables, resistance training has been a crucial part of physical exercise programs. Several reports highlight the various adaptive responses it provides, with a focus on the improvement in strength, balance, and muscular endurance that enables a more active and healthy lifestyle. Resistance training programs that are acute, sub-chronic, or chronic can help people with varying ages, conditions, and pathologies reduce their arterial hypertension. However, molecular mechanisms associated with resistance training to reduce blood pressure still need to be better understood. Thus, we aimed to understand the main effects of resistance training on blood pressure as well as the associated molecular mechanisms.

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OBJECTIVE: The aim of this study was to identify suitable polynomial regression for modeling the average growth trajectory and to estimate the relative development of the rib eye area, scrotal circumference, and morphometric measurements of Guzerat young bulls. METHODS: A total of 45 recently weaned males, aged 325.8±28.0 days and weighing 219.9±38.05 kg, were evaluated. The animals were kept on Brachiaria brizantha pastures, received multiple supplementations, and were managed under uniform conditions for 294 days, with evaluations conducted every 56 days. The average growth trajectory was adjusted using ordinary polynomials, Legendre polynomials, and quadratic B-splines. The coefficient of determination, mean absolute deviation, mean square error, the value of the restricted likelihood function, Akaike information criteria, and consistent Akaike information criteria were applied to assess the quality of the fits. For the study of allometric growth, the power model was applied. RESULTS: Ordinary polynomial and Legendre polynomial models of the fifth order provided the best fits. B-splines yielded the best fits in comparing models with the same number of parameters. Based on the restricted likelihood function, Akaike's information criterion, and consistent Akaike's information criterion, the B-splines model with six intervals described the growth trajectory of evaluated animals more smoothly and consistently. In the study of allometric growth, the evaluated traits exhibited negative heterogeneity (b<1) relative to the animals' weight (p<0.01), indicating the precocity of Guzerat cattle for weight gain on pasture. CONCLUSION: Complementary studies of growth trajectory and allometry can help identify when an animal's weight changes and thus assist in decision-making regarding management practices, nutritional requirements, and genetic selection strategies to optimize growth and animal performance.

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Cardiovascular and metabolic diseases such as hypertension, type 2 diabetes, and obesity develop long-term fibrotic processes in the heart, promoting pathological cardiac remodeling, including after myocardial infarction, reparative fibrotic processes also occur. These processes are regulated by many intracellular signaling pathways that have not yet been completely elucidated, including those associated with microRNA (miRNA) expression. miRNAs are small RNA transcripts (18-25 nucleotides in length) that act as posttranscriptionally regulators of gene expression, inhibiting or degrading one or more target messenger RNAs (mRNAs), and proven to be involved in many biological processes such as cell cycle, differentiation, proliferation, migration, and apoptosis, directly affecting the pathophysiology of several diseases, including cardiac fibrosis. Exercise training can modulate the expression of miRNAs and it is known to be beneficial in various cardiovascular diseases, attenuating cardiac fibrosis processes. However, the signaling pathways modulated by the exercise associated with miRNAs in cardiac fibrosis were not fully understood. Thus, this review aims to analyze the expression of miRNAs that modulate signaling pathways in cardiac fibrosis processes that can be regulated by exercise training.

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This study aimed to assess the impact of two commercial Saccharomyces cerevisiae strains (CHY1 and CHY2) on the intestinal health and performance of weaned piglets challenged with enterotoxigenic Escherichia coli during the nursery phase. One hundred ninety-two piglets with an average weight of 6.70 ± 0.92 kilograms were allocated in a randomized block design to one of four treatments: a negative control (C) without E. coli challenge and no yeast supplementation; a positive control (CH) with E. coli challenge and no yeast supplementation; and two treatment groups receiving an E. colichallenge with a CHY1 and CHY2 yeast strain supplementation. The challenge involved inoculating piglets with two dosages of E. coli F4 (106 CFU/ml and 109 CFU/ml) and a saline solution for the C group. Samples of intestinal tissue, blood, and cecal content were collected on the trial's 11th, 28th, and 42nd days. All variables were subjected to analysis of variance, and upon detecting significant differences via the F-test (p < 0.05), Tukey's test was applied to compare treatment means. For the analysis of diarrhea occurrence, the Kruskal-Wallis test was applied. When variables were rejected at a 5% probability level, a Dunn's test was conducted as a post-hoc analysis for paired multiple comparisons (p < 0.05), with statistical significance set at this level. Weaned piglets supplemented with CHY1 exhibited superior performance metrics, including higher average daily gain (15.3% increase), body weight (3.4% increase), feed-to-gain ratio (9.5% increase), and average daily feed intake (12.3% increase) at 28 days compared to the CH group across two different nutritional phases. No discernible effects were observed on measuring blood parameters, intestinal morphology, or cecal short-chain fatty acids. Both yeast-treated groups displayed improved performance during the most challenging periods. However, the CHY1 yeast strain contributed to enhanced piglet performance in the initial 28 days without inducing changes in intestinal morphology.(AU)

O presente estudo teve como objetivo avaliar duas cepas comerciais de Saccharomyces cerevisiae (designadas como CHY1 e CHY2) sob a saúde intestinal e desempenho de leitões desmamados desafiados com Escherichia coli enterotoxigênica durante a fase de creche. Um total de 192 leitões com peso médio 6,70 ± 0.92 quilogramas foram distribuídos em um delineamento em blocos casualizados com quatro tratamentos: um controle negativo (C) sem desafio de E. coli e sem suplementação da levedura; um controle positivo (CH) com desafio de E. coli e sem a suplementação da levedura; e dois grupos com a suplementação das dietas com as cepas comerciais das leveduras intituladas CHY1 e CHY2, juntamente ao desafio de E. coli. O desafio envolveu a inoculação de duas doses de E. coli F4 (106 UFC/ml e 109 UFC/ml) nos leitões e uma inoculação de solução salina para o grupo C. Amostras de tecido intestinal, sangue e conteúdo cecal foram coletadas nos 11º, 28º e 42º dias do experimento. Todas as variáveis foram submetidas a análise de variância e quando detectada diferença significativa pelo teste de F (p<0,05), o teste de Tukey foi aplicado para comparar as médias. Para a avalição da ocorrência de diarreia, o teste de Kruskal-Wallis foi aplicado e quando as variáveis foram rejeitadas ao nível de 5% de probabilidade, o teste de Dunn foi conduzido como uma análise post-hoc para comparações múltiplas (p<0,05) com significância estatística nesse nível. Leitões desmamados suplementados com CHY1 apresentaram métricas de desempenho superiores, incluindo maior ganho de peso diário (aumento de 15.3%), peso vivo (aumento de 3.4%), consumo de ração diário (aumento de 9.5%) e melhor eficiência alimentar (aumento de 12.3%) até os 28 dias de experimento em comparação com o grupo CH. Não foram observados efeitos dos tratamentos sobre os parâmetros sanguíneos mensurados, morfologia intestinal ou ácidos graxos de cadeia curta presentes no conteúdo cecal. Ambos os grupos tratados com leveduras apresentaram melhor desempenho durante os períodos mais desafiadores. No entanto, a cepa de levedura CHY1, especificamente, contribuiu para um melhor desempenho dos leitões nos primeiros 28 dias, sem induzir alterações na morfologia intestinal.(AU)

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Since it was described, wide-awake local anaesthesia no tourniquet (WALANT) has gained popularity. Our department has started using WALANT for hand surgery with increasing complexity. We present our results with WALANT rhizarthrosis surgery, including prosthetic replacement, trapeziectomy with suture button suspensionplasty and revision surgery. A retrospective review of all rhizarthrosis procedures under WALANT was performed from April 2021 to July 2022. We included patients who fulfilled inclusion criteria and had adequate imaging and clinical follow-up. A satisfaction survey was performed by telephone. Surgical time, complications, conversion to conventional anesthesia, pain, anxiety and global satisfaction were recorded. Tumescent anesthesia is performed 20-25 minutes before surgery, and is performed in four or five strategic locations that allow adequate anesthesia and vasoconstriction for the procedure to be comfortably carried out. We observed a series of 16 sequential surgeries involving 14 patients. All were female with a mean age of 65 years. Fourteen cases were performed due to primary rhizarthrosis, eight trapeziectomies with suture button suspensionplasty, six prosthetic replacements, and two revision surgeries. One patient needed to be converted to conventional anaesthesia due to anxiety during the procedure. Mean procedure time was 73 minutes. There were no WALANT-related complications. Mean patient-reported satisfaction with the anesthetic technique was a 9 (on a scale from 1 to 10) and 100% of patients would choose to undergo surgery with WALANT anesthesia for a future procedure. We find it useful to actively engage the patients during surgery to keep them comfortable and also help the surgeons assess stability and functional results. After wound closure, the hand is shown to the patient and he performs various tasks. There is somewhat of a learning curve for rhizarthrosis surgery under WALANT; patient comfort can be achieved through an adequate anesthetic technique and reassurance before and during surgery. We recommend that the first few cases be done in the presence of an anesthesiologist and a fasting patient in case there is a need to convert to conventional anesthesia. Wide awake rhizarthrosis surgery, even revision surgery, is safe and pain-free. Patient-reported satisfaction is also high. The authors find that including patient participation in their own surgery might be promising for post-op rehabilitation. There are limitations in this study such as the absence of a control conventional anesthesia group, the satisfaction questionnaire was not done immediately post-operatively, as such, a memory bias cannot be excluded, and it is not yet validated for the Portuguese population.

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We previously demonstrated that a 50% caloric restriction (CR) from birth improves several cardiometabolic risk factors in young rats. In this study, we investigated in middle-aged rats the consequences of a 50% CR from birth on cardiometabolic risk factors, heart function/morphology, ventricular arrhythmia, and fibrillation incidence, and cardiac intracellular proteins involved with redox status and cell survival. From birth to the age of 18 months, rats were divided into an Ad Libitum (AL18) group, which had free access to food, and a CR18 group, which had food limited to 50% of that consumed by the AL18. Resting metabolic rate, blood pressure, and heart rate were recorded, and oral glucose and intraperitoneal insulin tolerance tests were performed. Blood was collected for biochemical analyses, and visceral fat and liver were harvested and weighed. Hearts were harvested for cardiac function, histological, redox status, and western blot analyses. The 50% CR from birth potentially reduced several cardiometabolic risk factors in 18-month-old rats. Moreover, compared with AL18, the CR18 group showed a ∼50% increase in cardiac contractility and relaxation, nearly three to five times less incidence of ventricular arrhythmia and fibrillation, ∼18% lower cardiomyocyte diameter, and ∼60% lower cardiac fibrosis. CR18 hearts also improved biomarkers of antioxidant defense and cell survival. Collectively, these results reveal several metabolic and cardiac antiaging effects of a 50% CR from birth in middle-aged rats.

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Introduction: The sex difference in alcohol use disorder (AUD) is ingrained in distinctive neurobiological responses between men and women, which necessitates further investigation for a more tailored management. Methods: Minding the findings of iron dysregulation in AUD and the sex difference in iron homeostasis in multiple physiological and pathological settings, we examined the sex difference in the association between serum ferritin and blood alcohol concentration (BAC) in intoxicated males (n = 125) and females (n = 59). We included patients with both serum ferritin tested of any value and a BAC above the level of detection during the same hospital admission period. We investigated sex difference in the relationship between BAC, serum ferritin and liver enzymes in intoxicated critically ill and noncritically ill patients. Results: We found a negative association between serum ferritin and BAC in critically ill, intoxicated females [R2 = 0.44, F(1,14) = 11.02, p = 0.005], with much attenuated serum ferritin in females compared to their male counterparts (194.5 ± 280.4 vs. 806.3 ± 3405.7 ng/L, p = 0.002). We found a positive association between serum ferritin and liver enzymes [alanine transaminase (ALT) and aspartate transferase (AST)] in critically ill intoxicated females [ALT: R2 = 0.48, F(1,10) = 9.1, p = 0.013; AST: R2 = 0.68, F(1,10) = 21.2, p = 0.001] and in noncritically ill intoxicated males [ALT: R2 = 0.1, F(1,83) = 9.4, p = 0.003; AST: R2 = 0.1, F(1,78) = 10.5, p = 0.002]. The effect of BAC on serum ferritin was not mediated by ALT [indirect effect: (B = 0.13, p = 0.1)]. We also found a significant effect of sex, anemia, intensive care unit (ICU) admission and mortality on serum ferritin. Discussion: Our results suggest that high BAC in intoxicated female patients is associated with attenuated serum ferritin levels, questioning the role of low serum ferritin in female vulnerability to alcohol.

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Spintronic devices have recently attracted a lot of attention in the field of unconventional computing due to their non-volatility for short- and long-term memory, nonlinear fast response, and relatively small footprint. Here we demonstrate experimentally how voltage driven magnetization dynamics of dual free layer perpendicular magnetic tunnel junctions can emulate spiking neurons in hardware. The output spiking rate was controlled by varying the dc bias voltage across the device. The field-free operation of this two-terminal device and its robustness against an externally applied magnetic field make it a suitable candidate to mimic the neuron response in a dense neural network. The small energy consumption of the device (4-16 pJ/spike) and its scalability are important benefits for embedded applications. This compact perpendicular magnetic tunnel junction structure could finally bring spiking neural networks to sub-100 nm size elements.

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Coronavirus disease-19 (COVID-19), caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), is associated with the persistence of pre-existing or the emergence of new neurological and psychiatric manifestations as a part of a multi-system affection known collectively as "post-COVID syndrome." Cognitive decline is the most prominent feature among these manifestations. The underlying neurobiological mechanisms remain under intense investigation. Ferroptosis is a form of cell death that results from the excessive accumulation of intracellular reactive iron, which mediates lipid peroxidation. The accumulation of lipid-based reactive oxygen species (ROS) and the impairment of glutathione peroxidase 4 (GPX4) activity trigger ferroptosis. The COVID-19-associated cytokine storm enhances the levels of circulating pro-inflammatory cytokines and causes immune-cell hyper-activation that is tightly linked to iron dysregulation. Severe COVID-19 presents with iron overload as one of the main features of its pathogenesis. Iron overload promotes a state of inflammation and immune dysfunction. This is well demonstrated by the strong association between COVID-19 severity and high levels of ferritin, which is a well-known inflammatory and iron overload biomarker. The dysregulation of iron, the high levels of lipid peroxidation biomarkers, and the inactivation of GPX4 in COVID-19 patients make a strong case for ferroptosis as a potential mechanism behind post-COVID neuropsychiatric deficits. Therefore, here we review the characteristics of iron and the attenuation of ferroptosis as a potential therapeutic target for neuropsychiatric post-COVID syndrome.