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Chicory is a food with high nutritional. The use of beneficial elements in plants, such as sodium (Na) and silicon (Si), may be important to mitigate nutritional disorders, such as potassium (K) deficiency, but research is lacking on this topic. The objective was to evaluate the effects of sodium and nano-silicon on the nutritional, physiological, growth, and quality parameters of chicory under K deficiency and sufficiency. We used a concentration for sufficient K (3.0 mmol L-1), K-deficiency (1.5 mmol L-1), combined with the lack or presence of Na (2.0 mmol L-1) and Si (2.0 mmol L-1). The experiment was carried out in a greenhouse with six treatments corresponding to K sufficiency, K-sufficiency with Na, K-sufficiency with Si, K deficiency, K-deficiency with Na, and K-deficiency with Si, with six replications. The following growth variables were evaluated: (i) plant height, (ii) stem diameter, (iii) number of leaves, (iv) leaf area, and (v) plant biomass. Potassium and Si contents in the above ground part and K utilization efficiency were assessed, and the accumulation of K, Na, and Si was calculated. The efficiency of the quantum yield of photosystem II (Fv/Fm) and the photosynthetic pigments was determined. Electrolyte leakage index and relative water content, as well as phenolic compounds, ascorbic acid, and leaf firmness index were also determined. We found that supplying nano-Si and Na to a K-deficient nutrient solution increased K accumulation by 60% and 50% and K use efficiency by 79% and 62% compared to plants without supply of those elements. Nano-Si reduced electrolyte leakage, being 41% less than Na in K-deficient chicory. However, when Na was added to a nutrient solution with sufficient potassium, the K use efficiency decreased by 48% compared to sufficient potassium without Na. Under the same condition of sufficient supply of potassium and Na, K accumulation decreased by 20% in chicory compared to sufficient potassium without Na, and the photosynthetic pigments-total chlorophyll and carotenoids-were reduced by 5% and 10%, respectively. Our findings contribute to improve cultivation systems with low supply of K as the supply of Na and nano-Si mitigates the damage caused to the metabolism of chicory under K deficiency.

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The discovery of ferroelectricity in two-dimensional van der Waals materials has sparked enormous interest from the scientific community, due to its possible applications in next-generation nanoelectronic devices, such as random-access memory devices, digital signal processors, and solar cells, among others. In the present study, we used vapor phase deposition to synthesize ultrathin germanium sulfide nano-flakes on a highly oriented pyrolytic graphite substrate. Nanostructures of variable thicknesses were characterized using scanning tunneling microscopy and spectroscopy. Tunneling currents under forward and backward biases were measured as a function of nano-flake thickness. Remarkably, we clearly observed a hysteresis pattern, which we attributed to surface ferroelectric behavior, consistent with the screening conditions of polarization charges. The effect increases as the number of layers is reduced. This experimental result may be directly applicable to miniaturized memory devices, given the two-dimensional nature of this effect.

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The prediction of semiconductor device performance is a persistent challenge in materials science, and the ability to anticipate useful specifications prior to construction is crucial for enhancing the overall efficiency. In this study, we investigate the constituents of a solar cell by employing scanning tunneling microscopy (STM) and spectroscopy (STS). Through our observations, we identify a spatial distribution of the dopant type in thin films of materials that were designed to present major p-doping for germanium sulfide (GeS) and dominant n-doping for tin disulfide (SnS2). By generating separate STS maps for each semiconductor film and conducting a statistical analysis of the gap and doping distribution, we determine intrinsic limitations for the solar cell efficiency that must be understood prior to processing. Subsequently, we fabricate a solar cell utilizing these materials (GeS and SnS2) via vapor phase deposition and carry out a characterization using standard J-V curves under both dark/illuminated irradiance conditions. Our devices corroborate the expected reduced efficiency due to doping fluctuation but exhibit stable photocurrent responses. As originally planned, quantum efficiency measurements reveal that the peak efficiency of our solar cell coincides with the range where the standard silicon solar cells sharply decline. Our STS method is suggested as a prequel to device development in novel material junctions or deposition processes where fluctuations of doping levels are retrieved due to intrinsic material characteristics such as the occurrence of defects, roughness, local chemical segregation, and faceting or step bunching.

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PURPOSE: Patients with brain metastases are often referred for brain radiotherapy (BrRT) when exclusive palliative management would be more appropriate. To assess the indication of BrRT during end-of-life (EOL) care and evaluate the characteristics of the patients who underwent the treatment. METHODS: This retrospective study comprised patients from four independent oncology centers who had undergone BrRT for metastases. The variables included were Karnofsky performance status (KPS), primary tumor site, metastatic status, neurologic symptomatic status, the number and size of metastases, posterior fossa or meningeal involvement, type of BrRT, having undergone brain metastasectomy, and the availability of systemic therapies after BrRT. Patients were allocated into three subgroups with ≤30, 31-60, and 61-90 days of survival, and a control group of patients who survived >90 days. RESULTS: A total of 546 patients were included in the study. A KPS of <70 (P = .021), the number of brain metastases (P = .001), the lack of brain metastasectomy (P = .006), and the lack of systemic therapies after BrRT (P = .047) were significantly associated with the EOL subgroups. Multivariate analysis showed that a KPS of <70 (P < .001), the lack of brain metastasectomy (P = .015), and the lack of systemic therapies after BrRT (P = .027) were significantly associated with worse survival. In all, 241 (44.1%) patients died within 90 days-120 (22.0%) within 30 days, 75 (13.7%) within 31-60 days, and 46 (8.4%) within 61-90 days of BrRT. Patients with colorectal cancer were significantly more likely to die within 90 days of BrRT than >90 days. CONCLUSION: Considering patients' performance status and whether they are candidates for brain metastasectomy or systemic therapies after BrRT is critical to improving BrRT benefits in scenarios of EOL.

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MAIN CONCLUSION: Drought alone and drought plus warming will change the nutrient requirements and biomass distributions of Stylosanthes capitata, while warming will be advantageous only under well-watered condition for the next decades. Climate change effects on natural and managed ecosystems are difficult to predict due to its multi-factor nature. However, most studies that investigate the impacts of climate change factors on plants, such as warming or drought, were conducted under one single stress and controlled environments. In this study, we evaluated the effects of elevated temperature (+ 2 °C) (T) under different conditions of soil water availability (W) to understand the interactive effects of both factors on leaf, stem, and inflorescence macro and micronutrients concentration and biomass allocation of a tropical forage species, Stylosanthes capitata Vogel under field conditions. Temperature control was performed by a temperature free-air controlled enhancement (T-FACE) system. We observed that warming changed nutrient concentrations and plant growth depending on soil moisture levels, but the responses were specific for each plant organ. In general, we found that warming under well-watered conditions greatly improved nutrient concentration and biomass production, whilst the opposite effect was observed under non-irrigated and non-warmed conditions. However, under warmed and non-irrigated conditions, leaf biomass and leaf nutrient concentration were greatly reduced when compared to non-warmed and irrigated plants. Our findings suggest that warming (2 °C above ambient temperature) and drought, as well as both combined stresses, will change the nutrient requirements and biomass distributions between plant aerial organs of S. capitata in tropical ecosystems, which may impact animal feeding in the future.

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- Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense (Foc), is one of the most destructive diseases affecting banana crops worldwide. Therefore, the development of resistant cultivars is a promising alternative to mitigate the effects of the disease on banana plantations. The objectives of this study were to induce somaclonal variation in banana cultivars of the Silk and Cavendish types and to select somaclones resistant to subtropical race 4, thereby enabling the production of fruit in areas where this race is present. Shoot clump apexes of the Grand Naine and Maçã (Silk) cultivars were grown in MS medium. The cultures were subcultured four times. They were then challenged with fusaric acid (FA) in an experiment consisting of four treatments with different concentrations (0.1, 0.2, 0.3, and 0.4 mM) and five repetitions, each consisting of a Petri dish containing seven multiple shoot clumps in MS culture medium supplemented with 2.5 mg/L benzylamine purine. Multiple shoot clumps without the addition of FA were also used in the experiment, and were subcultured three times and maintained in a dark room. The multiple shoot clumps that survived the treatment with FA were transferred to MS medium and maintained in the growth chamber in the presence of light. The regenerated plants were later planted in tanks containing soil infested with an isolate classified as Foc subtropical race 4 (Foc STR4), and were evaluated for resistance to the pathogen at 90 days after inoculation (d.a.i.). Pathogen structures were confirmed by root clarification and root staining technique. All somaclones of the Maçã (Silk) cultivar were susceptible to Fusarium wilt and two somaclones of the Grand Naine cultivar were selected as resistant. The addition of FA as a selective agent was effective in the selection of somaclones among plants of the Grand Naine cultivar, as shown by the selection of two somaclones resistant to Foc STR4. The next step will consist of the agronomic and market potential validation of the selected somaclones, aiming to confirm their potential use by producers.

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The availability of information about population minorities, in this case, the LGBTQIA+ population (Lesbians, Gays, Bisexual, Transvestite/Transsexual, Queer, Intersex, and Asexual), and the possible intersections with other variables on population bases is essential for understanding the similarities and specificities of the reality experienced by these groups, and the establishment of focused public policies. In this sense, this paper aims to reflect on the problems related to research about the sex and gender orientations/performances and, consequently, the lack of information on this topic available in population databases. From the inclusion of the question about sexual orientation in the 2019 National Health Survey database, despite the limitations, this paper presents possible opportunities for investigations on the topic from different perspectives.

A disponibilidade de informações a respeito das minorias populacionais, nesse caso, da população LGBTQIA+ (Lésbicas, Gays, Bissexuais, Travestis e Transexuais, Queers, Intersexuais e Assexuais) e a possibilidade de cruzamentos com demais variáveis em bases populacionais é imprescindível para a compreensão das similaridades e especificidades da realidade vivenciada por estes grupos, bem como para a criação de políticas públicas focalizadas. Nesse sentido, buscamos refletir nesse artigo sobre os problemas relativos à investigação sobre as orientações/performances de sexo e gênero e, por consequência, a falta de informação sobre tal temática disponível nas bases de dados populacionais. A partir da inclusão da pergunta sobre orientação sexual na base de dados da Pesquisa Nacional de Saúde (PNS), de 2019, apesar das limitações, apresentamos algumas das possíveis oportunidades de investigações sobre o tema a partir de diferentes óticas.

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Resumo A disponibilidade de informações a respeito das minorias populacionais, nesse caso, da população LGBTQIA+ (Lésbicas, Gays, Bissexuais, Travestis e Transexuais, Queers, Intersexuais e Assexuais) e a possibilidade de cruzamentos com demais variáveis em bases populacionais é imprescindível para a compreensão das similaridades e especificidades da realidade vivenciada por estes grupos, bem como para a criação de políticas públicas focalizadas. Nesse sentido, buscamos refletir nesse artigo sobre os problemas relativos à investigação sobre as orientações/performances de sexo e gênero e, por consequência, a falta de informação sobre tal temática disponível nas bases de dados populacionais. A partir da inclusão da pergunta sobre orientação sexual na base de dados da Pesquisa Nacional de Saúde (PNS), de 2019, apesar das limitações, apresentamos algumas das possíveis oportunidades de investigações sobre o tema a partir de diferentes óticas.

Abstract The availability of information about population minorities, in this case, the LGBTQIA+ population (Lesbians, Gays, Bisexual, Transvestite/Transsexual, Queer, Intersex, and Asexual), and the possible intersections with other variables on population bases is essential for understanding the similarities and specificities of the reality experienced by these groups, and the establishment of focused public policies. In this sense, this paper aims to reflect on the problems related to research about the sex and gender orientations/performances and, consequently, the lack of information on this topic available in population databases. From the inclusion of the question about sexual orientation in the 2019 National Health Survey database, despite the limitations, this paper presents possible opportunities for investigations on the topic from different perspectives.

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The participation of plant cryptochromes in water deficit response mechanisms has been highlighted in several reports. However, the role of tomato (Solanum lycopersicum L.) cryptochrome 1a (cry1a) in the blue light fluence-dependent modulation of the water deficit response remains largely elusive. The tomato cry1a mutant and its wild-type counterpart were grown in water (no stress) or PEG6000 (osmotic stress) treatments under white light (60 µmol m-2 s-1) or from low to high blue light fluence (1, 5, 10, 15 and 25 µmol m-2 s-1). We first demonstrate that under nonstress conditions cry1a regulates seedling growth by mechanisms that involve pigmentation, lipid peroxidation and osmoprotectant accumulation in a blue light-dependent manner. In addition, we further highlighted under osmotic stress conditions that cry1a increased tomato growth by reduced malondialdehyde (MDA) and proline accumulation. Although blue light is an environmental signal that influences osmotic stress responses mediated by tomato cry1a, specific blue light fluence rates are required during these responses. Here, we show that CRY1a manipulation may be a potential biotechnological target to develop a drought-tolerant tomato variety. Nevertheless, the complete understanding of this phenomenon requires further investigation.

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