Incorporation of Conjugated Diynes in Perovskites and their Post-Synthetic Modification.

Two-dimensional (2D) organic-inorganic hybrid perovskites have rapidly become an attractive alternative to three-dimensional (3D) perovskites as solar cell absorbers, owing to their improved stability, versatility, and ease of processing. Despite their advantages, the insulating nature of the organic cations makes these materials have lower absorbing and conducting properties, resulting in lower device efficiencies. A way to circumvent these issues is the integration of functional molecules that help mitigate these limitations. In this study, six new perovskites composed of three distinct diynes are synthesized, all of which can be thermally polymerized to form conjugated polymers within the perovskite layers. The incorporation of conjugated polymers results in drastic changes in these materials' optoelectronic properties and their overall stability. Furthermore, depending on the nature of the diyne and the inorganic layers, the materials show varying polymerization yields, optical bandgaps, and charge carrier densities. These results afford significant insight into the chemical nature of the polymerized species and thus highlight the versatility of this approach to post-synthetically generate conducting polymers within the layers of 2D perovskites, paving the way toward their use in optoelectronic devices.

Prevalence and factors associated with urinary incontinence in women farmers / Prevalência e fatores associados à incontinência urinária em agricultoras

Abstract Introduction: Urinary incontinence (UI) is any involun-tary loss of urine, exhibiting a relationship with pelvic floor muscle weakness and overload. The physical exertion required of the woman farmer may predispose her to higher frequency of UI. Objective: To evaluate the prevalence of UI and associated factors in women farmers. Methods: Cross-sectional study, with appli-cation of an evaluation form and the International Consultation on Incontinence Questionnaire - Short Form (ICIQ-SF) in women aged between 25 and 50 years old. Women with urinary loss responded to the King's Health Questionnaire (KHQ). Data were collected by individual interview. The data were analyzed by absolute and relative frequency, using the Mann-Whitney test for intergroups and Spearman's Correlation Coefficient to relate the variables, considering p < 0.05. Results: Two hundred farmers were interviewed, where 52 (26%) reported involuntary urine loss. The incontinent group had a higher number of annual urinary infection (3.23 ± 1.40). Most incontinent women reported escape 1x/week or less (73.08%), in small amounts (82.69%), during stress (57.69%). Quality of life was classified as very good by 59.62%. The intensity of the work was considered strong by 25% of the incontinent women. Only 30.5% of the volunteers were able to define UI and 97.7% considered it not normal. Conclusion: The prevalence of UI was equivalent to the average of the female population in general, with urinary infection as an associated factor. The loss occurs mainly to stress, and lack of knowledge can reflect in the identification treatment.

Resumo Introdução: Incontinência urinária (IU) é qualquer perda involuntária de urina, apresentando relação com sobrecarga e fraqueza da musculatura do assoalho pélvico. O esforço físico exigido da mulher agricultora pode predispor à maior frequência de IU. Objetivo: Avaliar a prevalência e fatores associados à IU em mulheres agricultoras. Métodos: Estudo de corte transversal, com aplicação de ficha de avaliação e do International Consultation on Incontinence Questionnaire - Short Form (ICIQ-SF) em mulheres com idade entre 25 e 50 anos. As mulheres com perda urinária responderam ao King's Health Questionnaire (KHQ). A coleta de dados foi por entrevista individual. Os dados foram analisados por frequência absoluta e relativa, sendo empregado o teste de Mann-Whitney para intergrupos e o coeficiente de correlação de Spearman para relacionar as variáveis, considerando p < 0,05. Resultados: Duzentas mulheres agricultoras foram entrevistadas, das quais 52 (26%) referiram perda involuntária de urina. O grupo incontinente apresentou maior número de infecção urinária anual (3,23 ± 1,40). A maior parte das mulheres incontinentes referiram escape 1x/semana ou menos (73,08%), em pequena quantidade (82,69%) e durante o esforço (57,69%). A qualidade de vida foi classificada como muito boa por 59,62%. A intensidade do trabalho foi considerada forte por 25% das mulheres incontinentes. Apenas 30,5% das voluntárias souberam definir IU a e 97,7% consideram não ser normal. Conclusão: A prevalência de IU foi equivalente à média da população feminina em geral, tendo a infecção urinária como fator associado. A perda ocorre principalmente por conta de esforços e a falta de conhecimento pode dificultar a identificação e procura por tratamento.

Thousand-fold Conductivity Increase in 2D Perovskites by Polydiacetylene Incorporation and Doping.

Two-dimensional (2D) organic-inorganic perovskites have rapidly become an attractive alternative to traditional three-dimensional (3D) perovskite solar-cell absorbers owing to their improved stability and processability. Despite their advantages, the insulating nature of the organic cations and diminished light absorption limit their overall performance. Herein, it is demonstrated that the incorporation of conjugated diynes in hybrid 2D perovskites, and subsequent thermal treatment results in the formation of 2D perovskites that incorporate polydiacetylenes in their structure. Furthermore, it is shown that oxygen or iodine doping results in the formation of stable radicals within the material alongside a drastic shift of the band gap from 3.0 to 1.4 eV and in-plane conductivity improvements of up to three orders of magnitude, which lead to record conductivities for 2D halide perovskites (n=1).

Effects of ozone and chlorine disinfection on VBNC Helicobacter pylori by molecular techniques and FESEM images.

Helicobacter pylori is a pathogen bacteria associated with chronic gastritis, peptic ulceration, and gastric carcinoma. H. pylori has a spiral morphology, which under certain conditions of stress becomes a coccoid form. This type of morphology has been linked to a viable but non-culturable (VBNC) state, which is thought to allow its persistence in the environment. Membrane damage in VBNC H. pylori in water as a mechanism for inactivation using ozone (O3) and chlorine disinfection has not been reported in the literature. In this paper, disinfection assays with ozone and chlorine were conducted to evaluate their effects on VBNC H. pylori cells. The use of fluorescent dyes such as propidium monoazide (PMA) coupled with quantitative real-time polymerase chain reactions produced results necessary to assess the viability of the microorganism and demonstrate the effect of each disinfectant on the bacterial count. Applying ozone showed a 5-log bacterial reduction using a disinfectant concentration and exposure time (CT) of 4 mg min/L. Chlorine disinfection for the same 5-log reduction required a higher CT value. Field emission scanning electron microscope images of ozone-treated VBNC H. pylori also showed severe cell damage. The use of PMA revealed that chlorine produced physical damage in the membrane in addition to the known inhibiting effect on cell enzymatic processes. These findings are important for the detection and control of VBNC H. pylori cells in drinking water systems.