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Ionic liquids (ILs) are an extremely exciting class of electrolytes for energy storage applications. Upon dissolving alkali metal salts, such as Li or Na based salts, with the same anion as the IL, an intrinsically asymmetric electrolyte can be created for use in batteries, known as a salt-in-ionic liquid (SiIL). These SiILs have been well studied in the bulk, where negative transference numbers of the alkali metal cation have been observed from the formation of small, negatively charged clusters. The properties of these SiILs at electrified interfaces, however, have received little to no attention. Here, we develop a theory for the electrical double layer (EDL) of SiILs where we consistently account for the thermoreversible association of ions into Cayley tree aggregates. The theory predicts that the IL cations first populate the EDL at negative voltages, as they are not strongly bound to the anions. However, at large negative voltages, which are strong enough to break the alkali metal cation-anion associations, these IL cations are exchanged for the alkali metal cation because of their higher charge density. At positive voltages, we find that the SiIL actually becomes more aggregated while screening the electrode charge from the formation of large, negatively charged aggregates. Therefore, in contrast to conventional intuition of associations in the EDL, SiILs appear to become more associated in certain electric fields. We present these theoretical predictions to be verified by molecular dynamics simulations and experimental measurements.
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The fluid-fluid interface is a complex environment for a floating object where the statics and dynamics may be governed by capillarity, gravity, inertia, and other external body forces. Yet, the alignment of these forces in intricate ways may result in beautiful pattern formation and self-assembly of these objects, as in the case of crystalline order observed with bubble rafts or colloidal particles. While interfacial self-assembly has been explored widely, controlled manipulation of floating objects, e.g. drops, at the fluid-fluid interface still remains a challenge largely unexplored. In this work, we reveal the self-assembly and manipulation of water drops floating at an oil-air interface. We show that the assembly occurs due to electrostatic interactions between the drops and their environment. We highlight the role of the boundary surrounding the system by showing that even drops with a net zero electric charge can self-assemble under certain conditions. Using experiments and theory, we show that the depth of the oil bath plays an important role in setting the distance between the self-assembled drops. Furthermore, we demonstrate ways to manipulate the drops actively and passively at the interface.
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The Flory-Huggins theory describes the phase separation of solutions containing polymers. Although it finds widespread application from polymer physics to materials science to biology, the concentrations that coexist in separate phases at equilibrium have not been determined analytically, and numerical techniques are required that restrict the theory's ease of application. In this work, we derive an implicit analytical solution to the Flory-Huggins theory of one polymer in a solvent by applying a procedure that we call the implicit substitution method. While the solutions are implicit and in the form of composite variables, they can be mapped explicitly to a phase diagram in composition space. We apply the same formalism to multicomponent polymeric systems, where we find analytical solutions for polydisperse mixtures of polymers of one type. Finally, while complete analytical solutions are not possible for arbitrary mixtures, we propose computationally efficient strategies to map out coexistence curves for systems with many components of different polymer types.
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We evaluated the effects of fatty acid (FA) supplements with different ratios of palmitic acid (C16:0) and oleic acid (cis-9 C18:1) in low- and high-FA basal diets on production responses of lactating dairy cows. Thirty-six multiparous Holstein cows (50.2 ± 5.8 kg/d of milk; 160 ± 36 d in milk) were used in a split-plot Latin square design balanced for carryover effects. Cows were blocked by milk yield and allocated to a main plot receiving either a low-FA (LF; 1.93% FA content) basal diet (n = 18) containing cottonseed meal and cottonseed hulls or a high-FA (HF; 3.15% FA content) basal diet (n = 18) containing whole cottonseed. Within each plot, a 3 × 3 Latin square arrangement of treatments was used in 3 consecutive 21-d periods. Treatments were (1) control (CON; no FA supplementation), (2) FA supplement containing 80% C16:0 + 10% C18:1 (PA), and (3) FA supplement containing 60% C16:0 + 30% cis-9 C18:1 (PA+OA). The FA supplements were fed at 1.5% of dry matter and replaced soyhulls in CON. Preplanned contrasts were (1) overall effect of FA supplementation {CON vs. the average of the FA treatments [1/2 (PA + PA+OA)]}, and (2) the effect of the PA treatment versus the PA+OA treatment (PA vs. PA+OA). Treatment by basal diet interactions were observed for yields of milk and lactose, where FA treatments increased yields of milk and milk lactose in LF but not in HF. Basal diet had no effect on dry matter intake (DMI) or milk yield. Compared with LF, HF increased milk fat yield and 3.5% fat-corrected milk (FCM) and tended to increase milk fat content and energy-corrected milk (ECM) yield. The FA treatments decreased DMI but increased the yields of milk fat, 3.5% FCM, and ECM, compared with CON, due to increases in mixed and preformed milk FA yields. The PA+OA treatment decreased DMI and milk protein yield compared with PA. In conclusion, a high-fat basal diet increased milk fat production, and the addition of FA supplements to a low-fat basal diet increased milk lactose yield and tended to increase milk yield. Additionally, regardless of basal diet fat level, FA supplements increased production responses compared with the non-FA-supplemented control diet.
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Achatina fulica is a species native to East Africa, considered one of the 100 worst invasive alien species in the world. The present study investigated the population of the snail, A. fulica, in a peri-urban area adjacent to the Fiocruz Atlantic Forest Biological Station (EFMA), in Jacarepaguá, Rio de Janeiro state, Brazil, focusing on population dynamics and the nematodes associated with this species. To this end, specimens were collected during four climatic seasons of the years 2021 and 2022 in three fixed 20 m × 10 m plots. The abundance of A. fulica in these areas was evaluated in relation to a set of environmental variables (temperature, relative humidity air, and soil pH and calcium). The abundance of snails infected by nematodes was also evaluated in relation to the season and body size of the specimens. The molluscs were found by active search, and standardized (15 minutes/three collections). Nematode larvae were extracted from the specimens by artificial digestion and identified by their external morphology and the sequencing of molecular markers. A total of 280 specimens of A. fulica were collected, with the highest abundances being recorded in the autumn and summer, although no significant relationship was found between the number of specimens collected and the environmental variables. Overall, 192 snails were infected by nematodes: Angiostrongylus cantonensis, Cruzia tentaculata and free-living nematodes, including Caenorhabditis briggsae. These findings demonstrate the epidemiological importance of the study area and the need to implement educational measures in the community, with the aim of controlling the local A. fulica population, thereby minimizing the risk of parasitic infection in the local human population.
Assuntos
Angiostrongylus cantonensis , Caramujos , Infecções por Strongylida , Animais , Humanos , Brasil/epidemiologia , Espécies Introduzidas , Dinâmica PopulacionalRESUMO
There is no established treatment for patients with clozapine-resistant schizophrenia (CRS). Clozapine augmentation strategies with antipsychotics or others substances are effective in comparison with placebo while and Electroconvulsive therapy (ECT) showed to be effective in comparison with treatment as usual (TAU) but not with placebo (sham-ECT). In the present double- blind randomized controlled trial, we compared 40 outpatients who received 20 sessions of ECT (n = 21) or sham-ECT (n = 19) (age = 37.40 ± 9.62, males = 77.5 %, illness duration = 14.95 ± 8.32 years, mean total Positive and Negative Syndrome Scale (PANSS) = 101.10 ± 24.91) who fulfilled well-defined CRS criteria including baseline clozapine plasma levels ≥350 ng/mL. The primary outcome was the ≥50 % PANSS Total Score reduction; secondary outcomes were the scores of the PANSS subscales, PANSS five-factor dimensions, PANSS-6 and the Calgary Depression Rating Scale (CDRS). Treatment response was analyzed by percentage reduction, Linear Mixed Models and effect sizes. At baseline both groups showed no differences except for years of school education (included as a covariate). At endpoint, only 1/19 of the completers (5.26 %) in the ECT group and 0/17 in the sham-ECT group showed a ≥50 % total PANSS score reduction. Both groups showed no significant differences of the total PANSS score (F = 0.12; p = 0.73), Positive (F = 0.27, p = 0.61), Negative (F = 0.25, p = 0.62), and General Psychopathology scores (F = 0.01, p = 0.94) as well for all PANSS five factors, the PANSS-6 and CDRS. Thus, the present study found no evidence that ECT is better than Sham-ECT in patients with CRS. Future sham-ECT controlled studies with larger sample sizes are warranted to test the efficacy of ECT for patients with CRS.
Assuntos
Antipsicóticos , Clozapina , Eletroconvulsoterapia , Esquizofrenia Resistente ao Tratamento , Humanos , Masculino , Feminino , Eletroconvulsoterapia/efeitos adversos , Adulto , Clozapina/uso terapêutico , Clozapina/efeitos adversos , Método Duplo-Cego , Antipsicóticos/uso terapêutico , Pessoa de Meia-Idade , Esquizofrenia Resistente ao Tratamento/terapia , Esquizofrenia Resistente ao Tratamento/tratamento farmacológico , Escalas de Graduação Psiquiátrica , Resultado do Tratamento , Esquizofrenia/terapia , Esquizofrenia/tratamento farmacológico , Avaliação de Resultados em Cuidados de SaúdeRESUMO
Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas no responses were recorded in the 1.0, 2.0, and 6.0 mg/kg groups. T group individuals were fed young specimens of Astyanax sp previously injected with MeHg corresponding to 0.75 (N = 1 retina), 0.075 (N = 8 retinas) or 0.0075 (N = 4 retinas) mg/kg fish body weight. After 14 doses, one every 5 days, the amplitude of the horizontal cell response was higher than control in individuals exposed to 0.075 and 0.0075 mg/kg, and lower in individuals exposed to 0.75 mg/kg. We conclude that intoxication with MeHg affects the electrophysiological response of the horizontal cells in the retina, either reducing or increasing its amplitude compared to control, and that these effects are related to the dose and/or to the mode of administration.
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Animais , Peixes , Compostos de Metilmercúrio/toxicidade , Células Horizontais da Retina/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletrofisiologia , Compostos de Metilmercúrio/administração & dosagem , Células Horizontais da Retina/fisiologiaRESUMO
La Terapia de Reemplazo Hormonal (TRH) tiene una evolución histórica definitiva a lo largo de los últimos 50 años, habiendo pasado por fases evolutivas específicas, determinadas por estudios epidemiológicos, que nos van enseñando en cada publicación la mejor manera de abordar el tratamiento de la mujer en la postmenopausia. Las dosis hormonales más elevadas han perdido espacio, en los últimos años, respecto a las bajas dosis, principalmente por dos motivos específicos: efectos colaterales y miedo de cáncer. Los autores hacen una revisión de los estudios recientemente publicados acerca del tema y concluyen que las bajas dosis son una de las mejores opciones terapéuticas, pues es eficaz en la resolución de los mayores problemas climatéricos (oleadas de calor, sequedad vaginal y pérdida ósea), genera menos efectos adversos, además de exponer menos al paciente al riesgo de cáncer de mama y endometrio
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Terapia de Reposição Hormonal , Posologia HomeopáticaRESUMO
A análise de dois fármacos diferentes, mas estruturalmente semelhantes, foi realizada, empregando espectros de reflexão difusa no infravermelho médio com transformada de Fourier (DRIFTS), em associação com a técnica de análise por agrupamentos hierárquicos (AAH). Amostras de 3 diferentes farmácias de manipulação, contendo diclofenaco de sódio 50mg, diclofenaco de potássio 50mg e seus respectivos excipientes, foram analisadas em duplicata por dois analistas. Para a análise multivariada foi empregado o aplicativo Pirouette R 2.7 da Infometrix, selecionando-se o conjunto de regiões dos espectros com maior número de informações. Os dendogramas foram construídos com os dados auto-escalados e correção do espalhamento de luz (MSC), utilizando três tipos de construções: simples, flexível e incremental. Com a aplicação da AAH, constatou-se a formação de diferentes grupos obedecendo à discriminação de cada princípio ativo, indicando seus fornecedores e, em separado, outro grupo. Estes resultados demonstram que a técnica DRIFTS, em conjunto com ferramentas quimioterápicas, constitui uma excelente opção para a caracterização de fármacos, gerando uma inovadora metodologia para auxiliar no controle da qualidade de processos industriais de produção de medicamentos
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Anti-Inflamatórios não Esteroides , Diclofenaco/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Avaliação de Medicamentos , Controle de QualidadeRESUMO
Se presenta un analisis retrospectivo de 210 pacientes, ingresados por estenosis hipertrofica del piloro (EHP) y tratados quirurgicamente, entre 1975 y 1994. El estudio revelo un predominio de varones primogonitos, eutroficos, con un peso de nacimiento superior a los 3.000 g.Los sintomas mas importantes fueron los vomitos, que se presentaron en el 98,75 por ciento de los casos. La constipacion tuvo baja incidencia (22,85 por ciento). La oliva piloricase palpo en el 70,47 por ciento. La seriada esofagogastroduodenal confirmo el diagnostico en todos los pacientes. Hubo perforacion accidental de la mucosa en 6 casos (2,8 por ciento). La mortalidad fue del 1,9 por ciento (4 casos)