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We combine theoretical and experimental X-ray absorption near-edge spectroscopy (XANES) to probe the local environment around cationic sites of bulk spinel cobalt tetraoxide (Co3O4). Specifically, we analyse the oxygen K-edge spectrum. We find an excellent agreement between our calculated spectra based on the density functional theory and the projector augmented wave method, previous calculations as well as with the experiment. The oxygen K-edge spectrum shows a strong pre-edge peak which can be ascribed to dipole transitions from O 1s to O 2p states hybridized with the unoccupied 3d states of cobalt atoms. Also, since Co3O4 contains two types of Co atoms, i.e., Co3+ and Co2+, we find that contribution of Co2+ ions to the pre-edge peak is solely due to single spin-polarized t2g orbitals (dxz, dyz, and dxy) while that of Co3+ ions is due to spin-up and spin-down polarized eg orbitals (dx2−y2 and dz2). Furthermore, we deduce the magnetic moments on the Co3+ and Co2+ to be zero and 3.00 μB respectively. This is consistent with an earlier experimental study which found that the magnetic structure of Co3O4 consists of antiferromagnetically ordered Co2+ spins, each of which is surrounded by four nearest neighbours of oppositely directed spins.

The water quality of lakes is highly dependent on external phosphorus (P) loading. The vast external loadings from sewage and other wastewater discharge that European lakes have historically received have been dramatically reduced today by improved wastewater treatment. Gaining knowledge of the catchment characteristics that influence external P-loading should enable predictions of the achievable water quality of lakes. In this study, we tested this proposition. Data from 90 new Danish lakes show no apparent relationship between the mean summer P-concentration and the size or land use of the catchments. The external P-loading and resulting annual P-concentration were further investigated on a representative subset of 12 of the new lakes, using six methods. Three of the methods used empirical estimates of P-transport from catchments, based on the national average P-transport, runoff-dependent P-transport, and crop-dependent P-transport, and the other three methods used different empirical models tested on the lakes. External P-loading was reliably predicted by several of the methods. The predictions of the annual P-concentration were highly dependent on the inclusion of annual runoff. However, the predicted P-concentrations were generally overestimated, most pronounced for the nutrient-poor and most recently established lakes. In these lakes, internal P-loading was found to be the most important factor in predicting achievable water quality.

Introdução: A obesidade está intimamente relacionada com a qualidade de vida, além disso fatores psicológicos e comportamentais podem explicar a relação entre obesidade e ansiedade/depressão, para incentivar a promoção de saúde, a aromaterapia é um recurso com resultados satisfatórios, pouco explorado na redução de ansiedade e peso em indivíduos obesos. Objetivo: Investigar a relação do uso do óleo essencial de Lavandula angustifolia na redução do escore de ansiedade e perda de peso em mulheres obesas. Matérias e Métodos: estudo de intervenção sem grupo controle, composto por mulheres obesas, os dados foram coletados de abril a outubro de 2019, foram analisadas medidas antropométricas (peso/altura), para mensurar a ansiedade foi utilizado o Inventario de Ansiedade de Beck (BAI). A intervenção foi massagem e inalação do óleo essencial de Lavandula angustifolia à 3%, diluída no óleo vegetal de amêndoas doces, totalizou 8 sessões de massagem, as quais tiveram duração de 35 minutos, além do contato com a lavanda durante a massagem, as participantes levaram para casa um frasco com o mesmo óleo do procedimento, para pingar 1(uma) gota no travesseiro antes de dormir, diariamente, pelos 30 dias que participariam da pesquisa. Resultados: Diminuição da ansiedade (p=0,002), assim como redução do peso (p=0,022), porém sem alterar o índice de massa corporal (p=0,110). Conclusão: A aromaterapia com o óleo essencial de Lavandula angustifolia pode ser usada como um tratamento alternativo para a redução de ansiedade e consequentemente perda de peso de pessoas com obesidade.

The spinel Co3O4 has many beneficial properties for potential use in catalysis. In operando, water is always present and alters the properties of the catalyst. We have used ab initio molecular dynamics to understand the effect of water and solvation on the structure and reactivity of the Co3O4 (001) A-type and B-type surface terminations. Water adsorbs on both terminations via a partial dissociative mode, and the A-termination is seen to be more reactive. On this surface, a higher degree of dissociation is observed in the topmost layers of the crystal in contact with water. Water dissociates more frequently on the Co2+ sites (about 75%) than on the adjacent Co3+ sites, where the degree of dissociation is about 50%. Increasing water coverage does not change the degree of water dissociation significantly. OH− adsorption on the Co2+ sites leads to a reduction of the amount of reconstruction and relaxation of the surface relative to the clean surface at room temperature. Proton transfer within the water films and between water molecules and surface has localized character. The B-terminated interface is less dynamic, and water forms epitactic layers on top of the Co3+ sites, with a dissociation degree of about 25% in the contact layer.

Recent studies have suggested the neuroinvasive potential of severe acute respiratory coronavirus 2 (SARS-CoV-2). Notably, neuroinvasiveness might be involved in the pathophysiology of coronavirus disease 2019 (COVID-19). Some studies have demonstrated that synapse-connected routes may enable coronaviruses to access the central nervous system (CNS). However, evidence related to the presence of SARS-CoV-2 in the CNS, its direct impact on the CNS, and the contribution to symptoms suffered, remain sparse. Here, we review the current literature that indicates that SARS-CoV-2 can invade the nervous system. We also describe the neural circuits that are potentially affected by the virus and their possible role in the progress of COVID-19. In addition, we propose several strategies to understand, diagnose, and treat the neurological symptoms of COVID-19.

Glioblastoma is the most common adult primary brain tumor that occurs in the central nervous system and is characterized by rapid growth and diffuse invasiveness with respect to the adjacent brain parenchyma, which renders surgical resection inefficient. Although it is a highly infiltrative tumor, it is rarely disseminated beyond the central nervous system, wherein extracranial metastasis is a unique but rare manifestation of this kind of tumor. It is very common for acquired immunodeficiency syndrome (AIDS) patients to be infected with the human immunodeficiency virus (HIV), which suggests that a possible association between HIV infection and tumor development exists. In this paper, we present a new case of a young patient’s HIV-associated glioblastoma, with glioblastoma metastasis within the T9 vertebral body and lymph nodes in the anterior neck tissue. Initially, the patient was diagnosed with a grade III plastic astrocytoma. The patient lived a normal life for a year while being treated with temozolomide, radiotherapy, and highly active antiretroviral therapy. However, the tumor quickly evolved into a glioblastoma. We believe that the drastic progression of the tumor from a grade III anaplastic astrocytoma to a metastatic glioblastoma is due to the HIV infection that the patient had acquired, which contributed to a weakened immune system, thus accelerating progression of the cancer.

The emergence of a new era reaching beyond current state-of-the-art ultrashort and ultraintense laser technology has been enabled by the approval of around € 850 million worth of structural funds in 2011–2012 by the European Commission for the installation of Extreme Light Infrastructure (ELI). The ELI project consists of three pillars being built in the Czech Republic, Hungary, and Romania. This challenging proposal is based on recent technical progress allowing ultraintense laser fields in which intensities will soon be reaching as high as I0 ∼ 1023 W cm−2. This tremendous technological advance has been brought about by the invention of chirped pulse amplification by Mourou and Strickland. Romania is hosting the ELI for Nuclear Physics (ELI-NP) pillar in Măgurele near Bucharest. The new facility, currently under construction, is intended to serve the broad national, European, and international scientific community. Its mission covers scientific research at the frontier of knowledge involving two domains. The first is laser-driven experiments related to NP, strong-field quantum electrodynamics, and associated vacuum effects. The second research domain is based on the establishment of a Compton-backscattering-based, high-brilliance, and intense γ beam with Eγ ≲ 19.5 MeV, which represents a merger between laser and accelerator technology. This system will allow the investigation of the nuclear structure of selected isotopes and nuclear reactions of relevance, for example, to astrophysics with hitherto unprecedented resolution and accuracy. In addition to fundamental themes, a large number of applications with significant societal impact will be developed. The implementation of the project started in January 2013 and is spearheaded by the ELI-NP/Horia Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH). Experiments will begin in early 2020.

Summary: Tumor-associated p53 mutations endow cells with malignant phenotypes, including chemoresistance. Amyloid-like oligomers of mutant p53 transform this tumor suppressor into an oncogene. However, the composition and distribution of mutant p53 oligomers are unknown and the mechanism involved in the conversion is sparse. Here, we report accumulation of a p53 mutant within amyloid-like p53 oligomers in glioblastoma-derived cells presenting a chemoresistant gain-of-function phenotype. Statistical analysis from fluorescence fluctuation spectroscopy, pressure-induced measurements, and thioflavin T kinetics demonstrates the distribution of oligomers larger than the active tetrameric form of p53 in the nuclei of living cells and the destabilization of native-drifted p53 species that become amyloid. Collectively, these results provide insights into the role of amyloid-like mutant p53 oligomers in the chemoresistance phenotype of malignant and invasive brain tumors and shed light on therapeutic options to avert cancer. : Structural Biology; Protein Structure Aspects; Biophysics; Cancer Subject Areas: Structural Biology, Protein Structure Aspects, Biophysics, Cancer

Alguns alunos ao ingressarem no ensino superior apresentam dificuldades na aprendizagem de matemática ou alguma defasagem oriunda do ensino anterior, e para superar estas dificuldades, instituições como a Universidade Federal de Santa Maria desenvolvem o curso de Extensão Pré-Cálculo na Transição: Ensino Médio/Ensino Superior. O objetivo do presente trabalho é relatar a dinâmica do desenvolvimento deste projeto, ministrado por alunos dos cursos de Licenciatura e Bacharelado em Matemática. Para tanto, foi realizada uma observação participante para compreender as ações desenvolvidas, e as implicações destas para os acadêmicos envolvidos. Ao longo dos cinco encontros que compõe a primeira etapa do projeto, os monitores, a professora coordenadora e o professor colaborador utilizaram exemplos, exercícios, vídeo, representações e explicações, sempre buscando propiciar a interação. Considera-se que projetos como este trazem significativos benefícios, aos monitores pela experiência e vivência docente e aos novos acadêmicos, por retomarem os conteúdos, aprender e adquirir o domínio de conceitos que serão necessários para a efetiva aprendizagem de Cálculo em diferentes cursos de graduação.

This work analyzes an index of thermal comfort adaptable to the summer period in the city of Pelotas - RS. Daily data for 9h, 15h, and 21h (local time) of meteorological variables (air temperature and relative humidity) were used, from 1985 to 2015, obtained byAgroclimatological Station of Embrapa (Brazilian Company of Agricultural Research). In order to represent daily thermal comfort, twobiometeorological indexes were analyzed: Heat Index (HI) and Humidex Index (HU), during the mornings, afternoons and evenings. The results showed that the Humidex Index presented, on most days, heat stress, mainly in January, considering all periods of the day(mornings, afternoons and nights), while the Heat Index presented, the condition of thermal stress only in the afternoon.

O presente estudo teve como objetivo avaliar o potencial de uso de imagens de alta resolução espacial para a extração da área de copa de árvores em floresta nativa utilizando classificação supervisionada. Uma imagem do sensor multiespectral a bordo do satélite Worldview-2 foi adquirida, na qual foram testados três algoritmos de classificação digital de imagens. Com os resultados das classificações, foram delimitadas 51 copas de árvores, que foram localizadas em campo para a coleta de informações como diâmetro na altura do peito (DAP), altura estimada, diâmetro de base, identificação, e medição de 8 raios de copa para formar a área de copa (AC). O algoritmo SVM apresentou o melhor resultado dentre os métodos de classificação testados. Foi encontrado um R² de 0,57 entre AC em campo e o DAP. A relação AC/DAP indica que houve um aumento da área de copa à medida que aumentou o DAP. O R² entre a AC obtida por satélite e o DAP foi de 0,55. A obtenção do parâmetro AC via classificação supervisionada pode servir de base para delimitação de copas, porém, deve-se ter cuidado com este processo para não superestimar as áreas, devido à complexidade do dossel de uma floresta nativa.

Lymphoedema is a worldwide pandemic causing swelling of tissues due to dysfunctional transport of lymph fluid. Present management concepts are based in conservative palliation of symptoms through manual lymphatic drainage, use of compression garments, manual lymph drainage, exercise, and skin care. Nevertheless, some curative options as autologous lymph node transplantation were shown to reduce lymphoedema in selected cases. Lately, some concern has arisen due to reports of donor site morbidity. A possible solution could be the development of artificial lymph node scaffolds as niches of lymphatic regeneration. Engineering these scaffolds has included cryopreservation of lymph node stroma. However, the effects of cryopreservation on the regeneration capacities of these organs were unknown.

Abstract Hedgehog (Hh) signaling pathway plays an essential role during vertebrate embryonic development and tumorigenesis. It is already known that Sonic hedgehog (Shh) pathway is important for the evolution of radio and chemo-resistance of several types of tumors. Most of the brain tumors are resistant to chemotherapeutic drugs, consequently, they have a poor prognosis. So, a better knowledge of the Shh pathway opens an opportunity for targeted therapies against brain tumors considering a multi-factorial molecular overview. Therefore, emerging studies are being conducted in order to find new inhibitors for Shh signaling pathway, which could be safely used in clinical trials. Shh can signal through a canonical and non-canonical way, and it also has important points of interaction with other pathways during brain tumorigenesis. So, a better knowledge of Shh signaling pathway opens an avenue of possibilities for the treatment of not only for brain tumors but also for other types of cancers. In this review, we will also highlight some clinical trials that use the Shh pathway as a target for treating brain cancer.

In this study we present the proposal of a Potentially Significant Teaching Unit (UEPS) for the teaching of electromagnetism from an electric circuit capable of transforming the sound energy emitted by the loudspeaker into electric energy to recharge the battery. This circuit was considered significant to present the relations between the concepts worked, for example, electric current and electromagnetic induction with the operation of speakers and microphones. For this purpose, academics of the Graduation Course in Natural Sciences (UNIPAMPA - Uruguaiana / RS) proposed to elaborate, implement and evaluate a UEPS to teach concepts of electromagnetism for secundary-schooll students, based on the use of the electric circuit that has shown to be an instrument that provokes the motivation of the learner, one of the necessary conditions for the meaningful learning to occur. At the end of the UEPS, the motivation on the part of the academics responsible for teaching with theoretical foundations based on the constructivist theory of Ausubel, as well as on the part of the students of high school through the predisposition to learn, evidenced throughout the meetings was notorious. The results obtained in the present study compare the advances, setbacks and stagnations of the participating students in relation to the evidences of meaningful learning indicated through the answers given by the students to the beginning and the end of the meetings. The data indicate that the conceptual evolution is due to the planning and application of the UEPS, which sought to constantly observe the sequential organization of the contents to be developed, in a manner consistent with the dependency relations that naturally exist between them. In addition to the organization of the contents foreseen in the planning of the UEPS, each meeting was considered prior knowledge of the student, as well as the presence of subsumes in their cognitive structure to enable the anchoring of new knowledge. It is reiterated that the fruits results obtained are in accordance with the principles of Ausubel's psychological theory, that in order to facilitate meaningful learning one must take into account: the student's previous knowledge, the predisposition to learn and that the material presented must be potentially significant.