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Mining environmental liabilities generate environmental pollution. The objective of the present study was to determine the yield of white clover (Trifolium repens) and orchard grass (Dactylis glomerata) cultivated in mining environmental passives adding black earth and compost as a substrate in the Buenaventura Julcani Huancavelica Company. The treatments were the combinations: 4: 3.1: 3.1: 3:1.1 kg of RP: RP, TN: RP, C: RP, TN, C respectively. They were distributed in four treatments with twelve experimental units for each species of leguminous and gramineous grass, we worked according to the completely randomized design (DCA) with a 2 x 4 factorial arrangement, the experimental unit being a treatment with twelve repetitions. The variables evaluated were: germination percentage (TG) and stem survival percentage (TST). For the statistical analysis, the SPSS software was used.

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We investigate an agent-based model for the emergence of corruption in public contracts. There are two types of agents: business people and public servants. Both business people and public servants can adopt two strategies: corrupt or honest behavior. Interactions between business people and public servants take place through defined payoff rules. Either type of agent can switch between corrupt or honest strategies by comparing their payoffs after interacting. We measure the level of corruption in the system by the fractions of corrupt and honest agents for asymptotic times. We study the effects of the group size of the interacting agents, the dispersion with respect to the average salary of the public servants, and a parameter representing the institutional control of corruption. We characterize the fractions of honest and corrupt agents as functions of these variables. We construct phase diagrams for the level of corruption in the system in terms of these variables, where three collective states can be distinguished: i) a phase where corruption dominates; ii) a phase where corruption remains in less than 50% of the agents; and iii) a phase where corruption disappears. Our results indicate that a combination of large group sizes of interacting servants and business people and small dispersion of the salaries of public servants, contributes to the decrease of systemic corruption in public contracts.

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Despite being one of the main components of anxiety and playing a pivotal role in how an individual perceives and copes with anxiogenic situations or responds to a given treatment, trait anxiety is paradoxically omitted in most animal models of anxiety. This is problematic and particularly more concerning in models that are used to screen drugs and other treatments for specific anxiety disorders and to investigate their neurobiological mechanisms. Our group has been engaged in the search for specific anxiety-related traits in animal models of anxiety. We developed two new lines of rats with strong phenotypic divergence for high (Carioca High-conditioned Freezing [CHF]) and low (Carioca Low-conditioned Freezing [CLF]) trait anxiety as expressed in the contextual fear conditioning paradigm. Here, we summarize key behavioral, pharmacological, physiological, and neurobiological differences in one these lines, the CHF rat line, relative to randomized-cross controls and discuss how far they represent a valid and reliable animal model of generalized anxiety disorder and so high trait anxiety.

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Fetal Alcohol Spectrum Disorder (FASD) is a collective name for lifelong physical and neurodevelopmental problems caused by the gestational consumption of alcohol affecting fetal development. In Brazil, the lack of awareness among healthcare professionals, and the scarcity of suitable diagnostic tools and trained clinicians, can contribute to the underestimation of FASD prevalence and severity. The present review aims to map and analyze studies conducted in Brazil on children and adolescents with FASD or a history of prenatal alcohol exposure (PAE). Additionally, it intends to report the psychometric properties of the neurodevelopmental assessment tools applied in the selected articles. Searches were carried out in the databases Scielo, LILACS, PePSIC, EMBASE, PsycINFO, Web of Science, selecting original clinical studies that have investigated the neurodevelopment of this population. From a total of 175 studies, ten articles fit the inclusion criteria in which 18 instruments were identified. The most reported deficits were related to language, general intelligence quotient (IQ), adaptive behavior, attention, and visual perception. Our results point to the need for more clinical research on FASD in Brazil, as well as for the standardization and validation of neurodevelopmental assessment tools for the accurate diagnosis of FASD in Brazil.

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The participation of the hippocampal formation in consolidation and reconsolidation of contextual fear memories has been widely recognized and known to be dependent on the activation of the cAMP response element (CRE) binding protein (CREB) pathway. Recent findings have challenged the prevailing view that over time contextual fear memories migrate to neocortical circuits and no longer require the hippocampus for retrieval of remote fearful memories. It has also recently been found that this brain structure is important for the maintenance and recall of remote fear memories associated with aversive events, a common trait in stress-related disorders such as generalized anxiety disorder (GAD), major depression, and post-traumatic stress disorder. In view of these findings, here we examined the putative role of CREB in the hippocampus of an animal model of GAD during the retrieval of remote contextual fear memories. Specifically, we evaluated CREB phosphorylation in the hippocampus of male Carioca High- and Low-conditioned Freezing rats (CHF and CLF, respectively) upon re-exposure of animals to contextual cues associated to footshocks weeks after fear conditioning. Age-matched male rats from a randomized crossbreeding population served as controls (CTL). Adrenal catecholamine levels were also measured as a biological marker of stress response. Seven weeks after contextual fear conditioning, half of the sample of CHF (n = 9), CLF (n = 10) and CTL (n = 10) rats were randomly assigned to return to the same context chamber where footshocks were previously administrated (Context condition), while the remaining animals were individually placed in standard housing cages (Control condition). Western blot results indicated that pCREB levels were significantly increased in the hippocampus of CHF rats for both Context and Control conditions when compared to the other experimental groups. CHF rats in the Context condition also exhibited significant more freezing than that observed for both CLF and CTL rats. Lastly, CHF animals in the Context condition displayed significantly higher adrenal catecholamine levels than those in the Control condition, whereas no differences in catecholamine levels were observed between Context and Control conditions for CLF and CTL rats. These findings are discussed from a perspective in which the hippocampus plays a role in the maintenance and recall of remote contextual fear memories via the CREB pathway.

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Pancreatic islets are mini-organs composed of hundreds or thousands of ɑ, ß and δ-cells, which, respectively, secrete glucagon, insulin and somatostatin, key hormones for the regulation of blood glucose. In pancreatic islets, hormone secretion is tightly regulated by both internal and external mechanisms, including electrical communication and paracrine signaling between islet cells. Given its complexity, the experimental study of pancreatic islets has been complemented with computational modeling as a tool to gain a better understanding about how all the mechanisms involved at different levels of organization interact. In this review, we describe how multicellular models of pancreatic cells have evolved from the early models of electrically coupled ß-cells to models in which experimentally derived architectures and both electrical and paracrine signals have been considered.

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Studies have shown high comorbidity of anxiety disorder and chronic pain; generalized anxiety disorder (GAD) and neuropathic pain are among these pathologies. Cannabidiol (CBD) has been considered a promising treatment for these conditions. This study investigated whether chronic systemic treatment with CBD alters pain in high- (CHF) and low-freezing (CLF) Carioca rats (GAD model) and control rats (CTL) submitted to chronic neuropathic pain. The rats were evaluated in the sensory aspects (von Frey, acetone, and hot plate tests) before the chronic constriction injury of the ischiatic nerve (CCI) or not (SHAM) and on days 13 and 23 after surgery. Chronic treatment with CBD (5 mg/kg daily) was used for ten days, starting the 14th day after surgery. The open field test on the 22nd also evaluated locomotion and anxiety-like behavior. CBD treatment had an anti-allodynic effect on the mechanical and thermal threshold in all lineages; however, these effects were lower in the CHF and CLF lineages. Considering emotional evaluation, we observed an anxiolytic effect in CTL+CCI and CHF+CCI after CBD treatment and increased mobility in CLF+SHAM rats. These results suggest that the CBD mechanical anti-allodynic and emotional effects can depend on anxiety level.

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Background: COVID-19 may be a new risk factor for stroke. Stroke in COVID-19 varies from 1.1 to 8.1%. Various pathophysiological pathways predispose SARS-CoV-2 infected patients to stroke. Aim: To describe COVID-19 patients with acute stroke in one Colombian Center. Methods: From March 6 2020 and March 6 2021 records of patients with acute stroke and in-hospital positive PCR (Polymerase Chain Reaction) test for Sars-CoV-2 infection were reviewed. Demographic, stroke and COVID-19 characteristics were extracted. Continuous variables were reported in means and ranges. Categorical variables were presented in frequencies and percentage. A descriptive narrative was performed. Results: Of 328 acute stroke patients 14 (4.2%) tested positive for PCR SARS-CoV-2. Mean age 56.4 years with 57% males. Five were (35.7%) without vascular risk factors but 9 (64.3%) overweight. Brain infarct diagnosed in 11 (78.5%), 53% with anterior circulation syndromes. Mean NIHSS score 11.8 and 7 (63%) received intravenous thrombolysis. Acute inflammatory blood biomarkers (D-dimer, ferritin, LDH elevated) were positive in all. 11 (78.5%) had symptomatic COVID-19 before stroke with a mean latency of 7 days. 12 (85.7%) had severe COVID-19 and 6 (42.8%) required mechanical ventilation. Outcome was unfavorable in 9 (64.3%) (The Modified Rankin Scale (mRS) > 2), mean hospital stay was 21.8 days and in-hospital case fatality rate was 14.2%. Conclusion: In susceptible individuals COVID-19 predisposes to stroke. Hypercoagulation and immune thrombosis may be at the culprit for this state. In Colombia, COVID-19 patients with stroke have similar characteristics to the described worldwide.

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Clinical psychologists often use the Beck Depression Inventory, 2nd edition (BDI-II), and Beck Anxiety Inventory (BAI) to aid in the diagnosis of mental health issues and verify the effectiveness of treatments. Despite this common practice, studies that implement a cross-cultural design to check psychometric properties and the invariance of these scales are still scarce in the literature, which can lead to biased results that prevent comparisons among different groups. The present study investigated the internal structure of both tools and their level of invariance. From a representative sample of undergraduate students from Spain (n = 1216), Portugal (n = 426), and Brazil (n = 315), Confirmatory Factor Analysis and Multigroup Confirmatory Factor Analysis were performed. The results revealed suitable fit indices for the two-factor structure of the BDI-II and BAI, assessed by Confirmatory Factor Analysis procedures. Additionally, the two-factor model of the BDI-II reached invariant properties at three levels, whereas the structural model of the BAI did not. Altogether, these results suggest using the BDI-II in this group in these three countries and imply that BAI scores should be interpreted cautiously.

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Alzheimer's disease is a neurodegenerative disorder that is characterized by progressive cognitive decline, particularly in declarative memory, and the presence of ß-amyloid plaques, neurofibrillary tangles, and cortical atrophy (especially in the temporal lobe). Unlike the relationship between the temporal cortex and declarative memory, nondeclarative memories (e.g., motor, fear, and other emotion-based memories) involve distinct neural structures. The present review investigates nondeclarative associative learning ability in Alzheimer's disease. We discuss eyeblink conditioning, fear conditioning, and other emotion-based learning and present the functions and brain areas that are involved in each type of learning. Evidence suggests that nondeclarative learning is also affected by Alzheimer's disease, although some forms of learning may be relatively preserved. Details about each nondeclarative associative learning process and the implications of these findings are presented.

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