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Objetivo: Determinar la frecuencia de cepillado y uso de pasta dental con flúor en niños de 4 a 6 años de edad, de la parroquia Ricaurte del cantón Cuenca. Materiales y Métodos: Se realizó un estudio descriptivo transversal de temporalidad actual, su universo fue de 1216 niños de 4 a 6 años de edad de la parroquia Ricaurte del cantón Cuenca. El tamaño de la muestra se calculó al cuantificar con un nivel de confianza del 95% y un margen de error del 5%, dando, una muestra de 233 niños, se aplicó la técnica de la encuesta para la toma de datos y estos se traspasaron a un software estadístico. Resultados: El 49.8% de los niños realizan el cepillado dental dos veces al día, el 42.9% utilizó una concentración de pasta dental de 1000 a 1100 ppm, el 67.8% aplicó la cantidad de pasta dental equivalente a un grano de alverja, el 61.8% de los padres tiene escolaridad secundaria y el 46.8% poseen un nivel de ingreso de $400 mensuales. Conclusión: La mayoría de los niños de 4 a 6 años de edad cepillan sus dientes dos veces al día, utilizando porcentajes de flúor de 1000 a 1100 ppm lo que corresponde a las concentraciones recomendadas por la asociación dental de odontología pediátrica.

Die ringöffnende Si‐Fluorierung einer Vielzahl von Azasilolderivaten Cyclo‐1‐(iPr2Si)−4‐X−C6H3−2‐CH2NR (4: R=2,6‐iPr2C6H3, X=H; 4 a: R=2,4,6‐Me3C6H2, X=H; 9: R=2,6‐iPr2C6H3, X=tBuMe2SiO; 10: R=2,6‐iPr2C6H3, X=OH; 13: R=2,6‐iPr2C6H3, X=HCCCH2O; 22: R=2,6‐iPr2C6H3, X=tBuMe2SiCH2O) mit verschiedenen 19F‐Fluoridquellen untersucht, optimiert und die gewonnenen Erfahrungen in einem translationalen Ansatz genutzt, um ein einfaches 18F‐Markierungsprotokoll für die Azasilolderivate [18F]6 und [18F]14 zu erstellen. Letzteres stellt eine potenziell klickbare CycloSiFA‐prothetische Gruppe dar, die bei der Entwicklung von PET‐Tracern unter Verwendung der Cu‐katalysierten Triazolbildung eingesetzt werden könnte. Auf der Grundlage unserer Ergebnisse hat CycloSiFA das Potenzial, ein neuer Einstieg in nicht‐kanonische Markierungsmethoden für die Entwicklung radioaktiver PET‐Tracer zu werden. [ABSTRACT FROM AUTHOR]

Copyright of Revista Pediatría de Atención Primaria is the property of LUA Ediciones 3.0 S.L. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study of aquifers of the Lece andesite complex (LAC) and its surroundings yielded a new procedural stepwise analysis that allowed the assessment of the origin of elements, particularly in areas affected by both anthropogenic and natural influences. The methodology uses the mineralogical composition of the rocks, including the elements available in rocks and groundwater. This study analyzes the element ratios B/Cl−, Na+/Ca2+, Ca2+/Mg2+, HCO3−/Cl−, and Na+/Na+ + Cl−; the correlations are coupled with a statistical analysis. In addition to reevaluating the already published water content, we provide an important new dataset. The results show that the main source of the water contamination with the elements B, F, U, As, Cu, Fe, Zn, Co, and Ni is the processes occurring at the contact between the groundwaters and non-altered/altered (propylitized) andesite rocks. This is also observed in the waters extracted from crystalline schists. The results may help develop an efficient use and assessment of the qualitative water potential of the LAC reservoirs. Similarly, the results highlight the applicability of the groundwaters, facilitating their regional research and use, further encouraging new initiatives for the preservation and protection of human and animal health. [ABSTRACT FROM AUTHOR]

This paper describes a practical method for obtaining the spectra of lights emitted by a fluor in a liquid scintillator (LS) using a digital camera. The emission wavelength results obtained using a digital image were compared with those obtained using a fluorescence spectrophotometer. For general users, conventional spectrophotometers are expensive and difficult to access. Moreover, their experimental measurement setup and processes are highly complicated, and they require considerable care in handling. To overcome these limitations, a feasibility study was performed to obtain the emission spectrum through image analysis. Specifically, the emission spectrum of a fluor dissolved in a liquid scintillator was obtained using digital image analysis. An image processing method was employed to convert the light irradiated during camera exposure into wavelengths. Hue (H) and wavelength (W) are closely related. Thus, we obtained an H-W response curve in the 400~450 nm wavelength region, using a light-emitting diode. Another relevant advantage of the method described in this study is its non-invasiveness in sealed LS samples. Our results showed that this method has the potential to accurately investigate the emission wavelengths of fluor within acceptable uncertainties. We envision the use of this method to perform experiments in chemistry and physics laboratories in the future. [ABSTRACT FROM AUTHOR]

Eine Reihe redox‐responsiver, Ferrocenyl‐substituierter Borane und Boronsäureester wurde dargestellt. Oxidation der Ferrocenyl‐Einheit zum entsprechenden Ferrocenium führte zu einer drastischen Erhöhung der Lewis‐Acidität, wobei sogar die des SbF5 übertroffen wird. Dies wurde sowohl experimentell als auch durch quantenchemische Rechnungen untersucht. Die resultierenden, stark Lewis‐aciden Borverbindungen wurden für katalytische C‐F‐ und S‐F‐Aktivierung verwendet. [ABSTRACT FROM AUTHOR]

Der vorliegende Aufsatz diskutiert die jüngsten Entwicklungen in der Forschung zu Grenzflächenphänomenen fluorierter Amphiphile und konzentriert sich auf Anwendungen, die die einzigartigen und vielfältigen Grenzflächeneigenschaften dieser Amphiphile ausnutzen. Vor allem bilden fluorierte Amphiphile stabile Aggregate mit oft deutlich anderer Morphologie als ihre nicht fluorierten Analoga. Folglich finden fluorierte Tenside vielfältigen Einsatz in Hochleistungsanwendungen wie dem Mikrofluidik‐unterstützten Screening. Darüber hinaus wird ihr fluorspezifisches Verhalten an der Fest/Flüssig‐Grenzfläche thematisiert, wie zum Beispiel die Bildung superhydrophober Beschichtungen nach der Abscheidung auf Oberflächen. Da fluorierte Tenside und perfluorierte Materialien im Allgemeinen potenzielle Umweltbedrohungen darstellen, werden auch die jüngsten Entwicklungen der Schadstoffsanierung durch ihre Adsorption an fluorierte Oberflächen bewertet. [ABSTRACT FROM AUTHOR]

Neutrinos are difficult to detect because they weakly interact with matter, making their properties least known. The response of the neutrino detector depends on the optical properties of the liquid scintillator (LS). Monitoring any characteristic changes in the LS helps to understand the temporal variation of detector response. In this study, a detector filled with LS was used to study the characteristics of the neutrinos detector. We investigated a method to distinguish the concentrations of PPO and bis-MSB, which are fluors added to LS, through a photomultiplier tube (PMT) acting as an optical sensor. Conventionally, it is very challenging to discriminate the flour concentration dissolved in LS. We employed the information of pulse shape and PMT coupled with the short-pass filter. To date, no literature report on a measurement using such an experimental setup has been published. As the concentration of PPO was increased, changes in the pulse shape were observed. In addition, as the concentration of bis-MSB was increased, a decrease in the light yield was observed in the PMT equipped with the short-pass filter. This result suggests the feasibility of real-time monitoring of LS properties, which are correlated with the fluor concentration, using a PMT without extracting the LS samples from the detector during the data acquisition process. [ABSTRACT FROM AUTHOR]

Redoxaktive N‐(Fluormethoxy)benzotriazole wurden aus Fluoressigsäure und Hydroxybenzotriazolen durch elektrocarboxylative Kopplung zugänglich gemacht. Nach Alkylierung werden diese zu wirksamen Monofluormethoxylierungsreagenzien, welche die photokatalytische C‐H‐Funktionalisierung von Aromaten ermöglichen. Dadurch kann durch Bestrahlung von 1‐(OCH2F)‐3‐Me‐6‐(CF3)benzotriazoliumtriflat mit blauem LED‐Licht in Gegenwart von [Ru(bpy)3(PF6)2] die Synthese von vielfältig funktionalisierten Arylmonofluormethylethern begünstigt werden. Diese Methode ermöglicht die späte Funktionalisierung biologisch relevanter Strukturen, ohne auf ökologisch problematische Halofluorkohlenwasserstoffe angewiesen zu sein. [ABSTRACT FROM AUTHOR]

Copyright of RGO: Revista Gaúcha de Odontologia is the property of RGO: Revista Gaucha de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Dental Science is the property of Brazilian Dental Science Journal-ICT-UNESP and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study of aquifers of the Lece andesite complex (LAC) and its surroundings yielded a new procedural stepwise analysis that allowed the assessment of the origin of elements, particularly in areas affected by both anthropogenic and natural influences. The methodology uses the mineralogical composition of the rocks, including the elements available in rocks and groundwater. This study analyzes the element ratios B/Cl−, Na+/Ca2+, Ca2+/Mg2+, HCO3−/Cl−, and Na+/Na+ + Cl−; the correlations are coupled with a statistical analysis. In addition to reevaluating the already published water content, we provide an important new dataset. The results show that the main source of the water contamination with the elements B, F, U, As, Cu, Fe, Zn, Co, and Ni is the processes occurring at the contact between the groundwaters and non-altered/altered (propylitized) andesite rocks. This is also observed in the waters extracted from crystalline schists. The results may help develop an efficient use and assessment of the qualitative water potential of the LAC reservoirs. Similarly, the results highlight the applicability of the groundwaters, facilitating their regional research and use, further encouraging new initiatives for the preservation and protection of human and animal health.

Resumo Introdução A fluoretação das águas de abastecimento tem sido apontada em estudos nacionais e internacionais como a mais eficiente e equânime forma de acesso a fluoretos na prevenção da cárie dentária. Objetivo Relatar os resultados do heterocontrole nas águas de abastecimento público do município de Colombo/PR, no período de dezembro de 2013 a novembro de 2014. Método Foram coletadas amostras mensais em 15 Unidades Básicas de Saúde, em dias da semana aleatórios, no período de 12/2013 a 11/2014. As amostras foram analisadas pelo método eletrométrico na Faculdade de Odontologia da Universidade Federal Fluminense. Resultados Foram analisadas 180 amostras, que variaram de

The aim of this study is to evaluate salivary remineralisation versus chemical remineralisation/infiltration of enamel, using different dentistry materials. The enamel changes were studied using confocal laser scanning microscopy (CLSM), and the depth of lesions and demineralisation/remineralisation/infiltration percentage were calculated. Additionally, the macro elemental composition of the teeth was performed using atomic absorption spectroscopy (AAS). Two studies were performed: (i) demineralisation of enamel in 3% citric acid and infiltration treatment with infiltration resin (Icon, DMG), remineralisation with Fluor Protector (Ivoclar Vivadent) and artificial saliva pH 8; and (ii) enamel demineralisation in saliva at pH 3 and remineralisation at salivary pH 8. The results showed that, firstly, for the remineralisation of demineralised enamel samples, Fluor Protector (Ivoclar Vivadent) was very effective for medium demineralised lesions followed by saliva remineralisation. In cases of deep demineralisation lesions where fluoride could not penetrate, low viscosity resin (Icon, DMG, Hamburg) effectively infiltrated to stop the demineralisation process. Secondly, remineralisation in salivary conditions needed supplementary study over a longer period, to analyse the habits, diet and nutrition of patients in detail. Finally, demineralisation/remineralisation processes were found to influence the macro elemental composition of enamel demineralisation, with natural saliva proving to be less aggressive in terms of decreasing Ca and Mg content. [ABSTRACT FROM AUTHOR]

The stability of 2D all nitrogen clusters containing from 6 to 96 nitrogen atoms, terminated with CF3 groups, has been explored using two computational models: dispersion corrected B3LYP functional and scaled opposite spin Møller-Plesset perturbation theory (SOS-MP2). Single point domain-based local pair natural orbital coupled-cluster theory calculations (DLPNO-CCSD(T)) was used for further energy refinement. All systems were found to be minima, and their stability increases with CF3/N ratio. Larger clusters and anion radicals were not dynamically stable, while some of the cation radicals were found to be minima on potential energy surface. The mechanism of cluster stabilization by CF3 groups is related with interaction of orbitals holding lone electron pairs and antibonding sigma orbitals. [ABSTRACT FROM AUTHOR]

Wir berichten über die einfache Herstellung eines neuen und lagerfähigen Magnesiumamids (iPr2N)2Mg (Magnesium‐bis‐diisopropylamid; MBDA), das sich als besonders geeignet für die nicht‐kryogene Magnesiierung von fluorsubstituierten Arenen und Heteroarenen erwiesen hat, um Arylmagnesiumamide (ArMgDA) oder Bis‐Heteroarylmagnesien (HetAr)2Mg in Kohlenwasserstoffen zu erhalten. Weitere Reaktionen mit Elektrophilen (Aldehyde, Ketone, Allylbromide, Arylhalogenide (Negishi‐Kreuzkupplung)) lieferten eine Reihe von polyfunktionellen fluorsubstituierten ungesättigten Bausteinen. Es wurden verschiedene Postfunktionalisierungen sowie NMR‐Untersuchungen beschrieben, die die dimere Struktur der Base bestätigten. [ABSTRACT FROM AUTHOR]

This paper describes a practical method for obtaining the spectra of lights emitted by a fluor in a liquid scintillator (LS) using a digital camera. The emission wavelength results obtained using a digital image were compared with those obtained using a fluorescence spectrophotometer. For general users, conventional spectrophotometers are expensive and difficult to access. Moreover, their experimental measurement setup and processes are highly complicated, and they require considerable care in handling. To overcome these limitations, a feasibility study was performed to obtain the emission spectrum through image analysis. Specifically, the emission spectrum of a fluor dissolved in a liquid scintillator was obtained using digital image analysis. An image processing method was employed to convert the light irradiated during camera exposure into wavelengths. Hue (H) and wavelength (W) are closely related. Thus, we obtained an H-W response curve in the 400~450 nm wavelength region, using a light-emitting diode. Another relevant advantage of the method described in this study is its non-invasiveness in sealed LS samples. Our results showed that this method has the potential to accurately investigate the emission wavelengths of fluor within acceptable uncertainties. We envision the use of this method to perform experiments in chemistry and physics laboratories in the future.

Neutrinos are difficult to detect because they weakly interact with matter, making their properties least known. The response of the neutrino detector depends on the optical properties of the liquid scintillator (LS). Monitoring any characteristic changes in the LS helps to understand the temporal variation of detector response. In this study, a detector filled with LS was used to study the characteristics of the neutrinos detector. We investigated a method to distinguish the concentrations of PPO and bis-MSB, which are fluors added to LS, through a photomultiplier tube (PMT) acting as an optical sensor. Conventionally, it is very challenging to discriminate the flour concentration dissolved in LS. We employed the information of pulse shape and PMT coupled with the short-pass filter. To date, no literature report on a measurement using such an experimental setup has been published. As the concentration of PPO was increased, changes in the pulse shape were observed. In addition, as the concentration of bis-MSB was increased, a decrease in the light yield was observed in the PMT equipped with the short-pass filter. This result suggests the feasibility of real-time monitoring of LS properties, which are correlated with the fluor concentration, using a PMT without extracting the LS samples from the detector during the data acquisition process.

Verbindungen von Hauptgruppenelementen in niedrigen Oxidationsstufen sind in der Lage, die Reaktivität von Übergangsmetallkomplexen nachzuahmen. Wie Letztere neigen niedervalente Hauptgruppenelementverbindungen zur Änderung ihrer Oxidationsstufe und Koordinationszahl um +2, wodurch sie die wesentlichen Voraussetzungen für oxidative Additionen erfüllen. Prominente Beispiele für Hauptgruppenelementverbindungen, die mit Organohalogeniden R−X (R=Alkyl, Aryl, X=F, Cl, Br, I) oxidative Additionen eingehen, sind Carbene und ihre höheren Analoga. Kürzlich wurde auch über Aluminyl‐Anionen berichtet, die wie Carbene und Silylene starke σ‐Bindungen von R−X‐Spezies oxidativ addieren können. Hier stellen wir nun mit dem Tris(pentafluorethyl)silanid‐Anion, [Si(C2F5)3]−, das erste Anion aus der 14. Gruppe vor, welches C−F‐Bindungen im Sinne einer oxidativen Addition zu spalten vermag. Dies ermöglichte die Isolierung von nicht‐chelatierten Tetraorganofluorosilicat‐Salzen, die unseres Wissens bisher nur als reaktive Zwischenstufen nachgewiesen wurden. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Die Photolyse von Diazoalkanen zur Durchführung von Singulett‐Carbentransferreaktionen gefärbter Diazoalkane hat in letzter Zeit großes Interesse in der organischen Synthese geweckt. Hier beschreiben wir einen photokatalytischen Ansatz, der den Zugang zu Triplettcarbenen über Energietransfer ermöglicht, um hocheffiziente gem‐Difluorolefinierungsreaktionen mit α‐Trifluormethylstyrolen durchzuführen. Die Verwendung eines tertiären Amins erwies sich als entscheidend, um diesen ungewöhnlichen Reaktionsweg zu erschließen und unerwünschte Cyclopropanierungsreaktionen zu verhindern. Das Amin erleichtert zudem die finale Abstraktion von Fluorid zum gem‐Difluorolefinen (43 Beispiele, bis zu 88 % Ausbeute), was durch experimentelle und theoretische mechanistische Studien gestützt wird. Wir haben diese Synthesemethode mit einem breiten Substratspektrum untersucht, das von einfachen Olefinen und heterocyclischen Olefinen bis hin zur Funktionalisierung pharmazeutisch relevanter Bausteine reicht. [ABSTRACT FROM AUTHOR]

Dans le domaine bucco-dentaire, le conseil officinal est complémentaire du travail du chirurgien-dentiste. En raison de sa proximité et de son accessibilité, l'équipe officinale est impliquée dans la prévention et l'éducation. De bonnes connaissances anatomiques et physiopathologiques de la bouche sont nécessaires pour prodiguer un conseil de qualité et proposer des produits adaptés en fonction de la typologie de ses clients. In the oral health field, the pharmacist's advice is complementary to the work of the dental surgeon. Because of its proximity and accessibility, the pharmacy team is involved in prevention and education. Good knowledge of the anatomy and pathophysiology of the mouth is necessary to provide quality advice and to offer products adapted to the type of client. [ABSTRACT FROM AUTHOR]

Pour lutter contre l'apparition des pathologies bucco-dentaires ou diminuer leur incidence et leur gravité, la prévention est indispensable. L'équipe officinale joue un rôle majeur en relayant des recommandations adaptées. To fight against the appearance of oral pathologies or reduce their incidence and severity, prevention is essential. The pharmacy team plays a major role in relaying appropriate recommendations. [ABSTRACT FROM AUTHOR]

As lesões de mancha branca são a primeira expressão clínica da desmineralização que ocorre na superfície do esmalte do dente. Nesse sentido, este trabalho objetiva relatar um caso clínico sobre tratamento de lesões de mancha branca ativas em paciente de 19 anos, tratada ortodonticamente por 2 anos. Após remoção do aparelho, verificou-se presença de manchas brancas ativas nos elementos dentários permanentes (n=10), as quais foram avaliadas clinicamente em relação à atividade (textura e luminosidade) e a dimensão (maior diâmetro cérvico-incisal e mésio-distal) e os dados anotados no prontuário da paciente. Os dados foram analisados num enfoque quantitativo e qualitativo, sendo confrontados com a literatura pertinente ao tema. Após orientação de higiene e dieta, 8 sessões de fluorterapia com o verniz fluoretado Duoflorid XII® da FGM (6% de fluoreto de cálcio e 6% de fluoreto de sódio) com profilaxia prévia usando pasta profilática SHINE® da Maquira (2000 ppm de F), foram observados os elementos: redução das médias de diâmetros cervico-oclusal e médio-distal finais em 08 elementos e manutenção das médias em 02. Além disso, 02 manchas brancas permaneceram ativas, as demais inativas. Conclui-se que houve remineralização das manchas brancas com redução do diâmetro e/ou atividade, após 8 sessões de terapia com verniz fluoretado e orientação quanto a higiene e dieta da paciente.

Objetivo: O flúor acidulado é utilizado no controle da doença cárie, mas seus efeitos na superfície de resinas compostas são controversos. O objetivo do estudo é avaliar a rugosidade superficial de uma resina composta após a aplicação tópica de flúor in vitro. Métodos: Espécimes de resina Vittra (FGM) foram preparados (8mmx1mm) e polidos. Após avaliação do pH de produtos fluoretados, o de maior e menor pH foram selecionados para os experimentos. Foram testados três grupos experimentais (n=15): grupo 1 – flúor gel acidulado a 1,23% (Nova DFL) (menor pH:4,48±0,32), grupo 2 – flúor gel neutro a 2% (Nova DFL) (maior pH:7,03±0,40), grupo 3 – sem exposição ao flúor (controle negativo). O experimento simulou o protocolo padrão clínico de aplicação de flúor (uma aplicação por semana, durante um minuto, por quatro semanas). A rugosidade superficial foi mensurada antes e após o tratamento através de microscopia confocal e a característica superficial avaliada por imagens reconstruídas. Foi realizado teste ANOVA (post-hoc de Bonferroni) para comparar médias da rugosidade superficial entre grupos. Resultados: O grupo exposto ao flúor gel acidulado apresentou os maiores valores de rugosidade (Ra: 0,29±0,08), sendo maior que o grupo exposto ao gel neutro (Ra: 0,21±0,08) e controle (Ra: 0,23±0,05) (p

Introduction: dental fluorosis is the hypomineralization of enamel produced as a result of fluoride intake for a prolonged period during enamel formation. The aim of the present study was to identify the factors associated with dental fluorosis in children and teenagers from the city of Montería, Colombia. Methods: a quantitative, descriptive and retrospective study was conducted in a sample of 136 dental fluorosis cases in schoolchildren aged 6, 12, 15 and 18 years reported to the Surveillance and Control System from January to December 2016. Results: there was fluoride exposure in 81.6% of schoolchildren covered by the subsidized health system—the mechanism by which the poorest population, with not enough resources to pay, can access health services through a subsidy offered by the state in Colombia—. 89% were from the municipal center, defined by Colombia’s National Administrative Department of Statistics (Departamento Administrativo Nacional de Estadística, DANE) as the geographical area bounded by an urban perimeter, where the administrative headquarters of a municipality are located. 47% of patients had cavities. Tooth brushing in a frequency higher than three times a day was predominant with 48.5%, and the use of toothpaste on more than 3/4 of the brush with 52%. 71.3% of patients said they did not swallow toothpaste, and 93.4% did not swallow mouthwash. 82.4% of patients did not receive topical fluoride in the last year. Conclusions: several factors are more highly associated with dental fluorosis, such as the amount of toothpaste during brushing, the habit of brushing three or more times a day, consumption of diet salt, and unintentional intakeof toothpaste at an early age. Most schoolchildren had a moderate degree of dental fluorosis.

The aim of this study is to evaluate salivary remineralisation versus chemical remineralisation/infiltration of enamel, using different dentistry materials. The enamel changes were studied using confocal laser scanning microscopy (CLSM), and the depth of lesions and demineralisation/remineralisation/infiltration percentage were calculated. Additionally, the macro elemental composition of the teeth was performed using atomic absorption spectroscopy (AAS). Two studies were performed: (i) demineralisation of enamel in 3% citric acid and infiltration treatment with infiltration resin (Icon, DMG), remineralisation with Fluor Protector (Ivoclar Vivadent) and artificial saliva pH 8; and (ii) enamel demineralisation in saliva at pH 3 and remineralisation at salivary pH 8. The results showed that, firstly, for the remineralisation of demineralised enamel samples, Fluor Protector (Ivoclar Vivadent) was very effective for medium demineralised lesions followed by saliva remineralisation. In cases of deep demineralisation lesions where fluoride could not penetrate, low viscosity resin (Icon, DMG, Hamburg) effectively infiltrated to stop the demineralisation process. Secondly, remineralisation in salivary conditions needed supplementary study over a longer period, to analyse the habits, diet and nutrition of patients in detail. Finally, demineralisation/remineralisation processes were found to influence the macro elemental composition of enamel demineralisation, with natural saliva proving to be less aggressive in terms of decreasing Ca and Mg content.

The north east of Tunisia ore deposits (Hammam Zriba) contain a large amount of fluorides constituting a risk of environmental pollution as well as risks to human and animal health. The aim of our work was to assess the levels of fluorides in the water and blood of sheep in the east of Tunisia region. This analysis study included 78 water samples and 60 blood samples taken during 3 days in the year 2019, from a sheep herd at Hammam Zriba delegation. The determination of fluorine concentration in the samples was carried out by potentiometry with a selective electrode type ISE combined Fluoride perfectION™. High Fluoride concentrations were found at a mean of 1.62 ± 1.18, 1.45 ± 0.98, and 2.65 ± 1.61 mg/l, respectively, in running, deep, and stagnant waters. In addition, 83.3% of the animals reared within 400 m of the study area had elevated fluoride levels in the blood exceeding the usual values (fluoremia> 0.15 mg/l). The concentration of fluoride in the blood of the animals decreases with increasing distance from the mine.

Hiermit berichten wir über die Herstellung von Silber(I)‐pentafluorooxosulfat aus kommerziell erhältlichem AgF und OSF4. Die Verbindung ist überraschend stabil in MeCN‐Lösungen. Darüber hinaus lässt sie sich durch Zugabe von 2,2′‐Bipyridin‐Liganden stabilisieren. Ausgehend von Lösungen des Silber(I)‐Salzes wurden OSF5‐Komplexe mit NiII‐, CuI‐ und CuII‐Zentren erhalten. Weiterhin konnte gezeigt werden, dass AgOSF5 grundsätzlich in der Lage ist, den Transfer von OSF5‐Gruppen an Arine zu vermitteln und somit eine neue und sichere Methode zur Herstellung OSF5‐substituierter Aromaten zu eröffnen. Die Röntgenstrukturanalyse ausgewählter Übergangsmetall‐OSF5‐Verbindungen offenbarte verzerrt oktaedrische [OSF5]−‐Anionen, die durch eine Vielzahl an Wasserstoffbrücken stabilisiert sind. [ABSTRACT FROM AUTHOR]

Eine durch Iod (I/III) Katalyse ermöglichte Strategie zur Konstruktion eines enantioangereicherten fluorierten Isoster der Isopropylgruppe wird beschrieben. Die in situ Generierung einer chiralen ArIF2‐Spezies ermöglicht die Difluorierung von leicht zugänglichen α‐CF3‐Styrolen, um ein Stereozentrum mit den Substituenten F, CH2F und CF3 aufzubauen (bis zu 95 %, >20:1 vicinale:geminale Difluorierung). Der Austausch des metabolisch labilen benzylischen Protons führt zu einem stark präorganisierten Gerüst, welches durch Röntgenstrukturanalyse nachgewiesen werden konnte (π→σ* und stereoelektronische gauche σ→σ* Wechselwirkungen). Um die Basis für die vorläufige Validierung der Enantioselektivität zu bilden, wurde eine Katalysatoroptimierung durchgeführt. [ABSTRACT FROM AUTHOR]

Fluorierte Organophosphor(V)‐Spezies sind eine vielseitige Klasse von Verbindungen. Ihre aktuell zur Verfügung stehenden Synthesemethoden haben jedoch die Nachteile der gelegentlichen Handhabung von toxischen oder pyrophoren PIII‐Ausgangsmaterialien und der Abhängigkeit von gefährlichen Fluorierungsreagenzien wie XeF2. Wir präsentieren hier eine alternative Methode zur Lösung dieser Probleme mittels Desoxyfluorierung (DOF) von einfach zu gebrauchenden Phosphanoxiden als Ausgangsmaterialien und vermeiden gleichzeitig aggressive Fluorierungsreagenzien durch eine Kombination von Oxalylchlorid und Kaliumfluorid. Die Reaktion hat sich als allgemein anwendbar erwiesen, da R3PF2‐, R2PF3‐ und RPF4‐Verbindungen (sowie verschiedene davon abgeleitete Kationen und Anionen) in guten Ausbeuten und im Multi‐Gramm‐Maßstab zugänglich sind. DFT‐Berechnungen wurden verwendet, um unsere Beobachtungen zu untermauern. Insbesondere führte die Entdeckung dieser neuen Methode zu einer bequemen Synthese von 1) neuen Difluorphosphoniumionen, 2) Hexafluorphosphatsalzen und 3) fluorierten Antimon‐ und Arsenverbindungen. [ABSTRACT FROM AUTHOR]

In arid and semiarid regions, groundwater becomes the main source to meet the drinking water needs of large cities, food production, and industrial activities. For this reason, necessary studies must be carried out to estimate its quantity and quality, always seeking sustainable management, thus avoiding social conflicts or a decrease in the productive activities of humanity. This research explains the behavior of groundwater quality concerning arsenic speciation and its relationship with fluoride. The average total arsenic concentration of 19.95 µg/L and 20.29 µg/L is reported for the study period from 2015 to 2020, respectively, according to the Mexican standard. If the population drinks water directly, it is exposed to possible damage to health. The predominant arsenic species is As (V), with 95% and As (III) with 5%, this finding will allow us to define in greater detail the type of remediation that is required to reduce the content of this element in the water. Regarding the relationship between arsenic and fluorine, very small Pearson correlation coefficients of the order of 0.3241 and 0.3186 were found. The estimation of the space–time variation made it possible to identify the areas with the highest concentration of arsenic and fluorine, allowing the definition of the operating policies of these wells, thereby protecting the health of the inhabitants who consume this water.

Copyright of Journal of Ege University School of Dentistry / Ege Üniversitesi Dis Hekimligi Fakültesi Dergisi is the property of Ege University Faculty of Dentistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Das Chromangerüst findet sich in einer Vielzahl von kleinen, bioaktiven Molekülen, in denen die 3‐Position häufig oxidiert wird. Motiviert durch die Wichtigkeit dieser Position für die Wirksamkeit sowie die Bedeutung der Bioisosterie in der Wirkstoffforschung wurde eine Iod(I)/Iod(III)‐Katalysestrategie für den Zugang zu enantiomerenangereicherten 3‐Fluorchromanen entwickelt (bis zu 7:93 e.r.). Die In‐situ‐Erzeugung von ArIF2 ermöglicht die direkte Fluorzyklisierung von Allylphenylethern, um neue Molekülgerüste zu erzeugen, die den stereoelektronischen gauche‐Effekt zeigen. Mechanistische Untersuchungen unter Verwendung von deuterierten Substraten bestätigen einen stereospezifischen Prozess, der mit einem Reaktionsverlauf des Typs IIinv übereinstimmt. [ABSTRACT FROM AUTHOR]

The two enantiomers of trifluoromethyl‐benzo[c][1,5]oxazonines, (R)‐4 and (S)‐4, can be selectively accessed with high enantiopurity by the Pd‐catalyzed ring‐expansion reaction of trifluoromethyl‐benzo[d][1,3]oxazinones (1) with vinyl ethylene carbonates (3) using one antipode of a chiral ligand. Initially, the reaction proceeds by a double decarboxylative ring‐expansion with kinetic resolution of 1 in the presence of a Pd‐catalyst/chiral ligand to provide (R)‐4 with high enantiopurity. At the same time, the nonreactive antipode of 1, (S)‐1, which was recovered with an impeccable s factor of up to 713 and an ideal chemical yield, was transferred into the antipode of the products, (S)‐4, with high enantiopurity by a second run of the Pd‐catalyzed double decarboxylation reaction, but this time without any chiral auxiliary. Thus, both antipodes of the chiral trifluoromethyl heterocycles 4 can be obtained in excellent enantiopurity using only a single antipode of the chiral catalyst. [ABSTRACT FROM AUTHOR]

In diesem Artikel berichten wir über die palladiumkatalysierte Reaktion von Indolen mit fluorierten Diazoalkanen. Dieser Ansatz bietet nun erstmalig eine einfache Methode für die effiziente Synthese von gem‐Difluorolefinen unter milden Reaktionsbedingungen mit fluorierten Diazoalkane. Diese reagieren mit N‐alkylierten Indolen in einer C‐H‐Funktionalisierung gefolgt von einer β‐Fluorideliminierungsreaktion. Die entsprechenden Cyclopropanierungsprodukte werden erhalten, wenn in dieser Reaktion N‐arylierte Indole eingesetzt werden. In mechanistischen Studien können wir zeigen, dass eine β‐Fluorideliminierung einen zentralen Reaktionsschritt darstellt. Diese Methode ist damit ein neuartiges Konzept, das den einfachen und direkten Transfer einer 1‐Aryl‐(2,2‐difluorvinyl)‐Gruppe für die Synthese von gem‐Difluorolefinen ermöglicht. [ABSTRACT FROM AUTHOR]

In der organischen Synthese wird Hexafluorisopropanol üblicherweise als nicht reaktives Lösungsmittel und nicht als Reagens angesehen. In diesem Artikel berichten wir über die photochemische Reaktion von Aryldiazoacetaten mit Hexafluorisopropanol, die unter stöchiometrischen Bedingungen die milde und effiziente Synthese von fluorierten Ethern in hervorragender Ausbeute ermöglicht. In mechanistischen Studien konnten wir feststellen, dass eine Präorganisation von Hexafluorisopropanol und dem Diazoalkan unter Ausbildung eines unreaktiven Wasserstoffbrückenbindungskomplexes stattfindet. Dieser Komplex geht erst nach photochemischer Anregung eine Protonierungs‐Substitutionsreaktion zum Reaktionsprodukt ein. Abschließend führten wir Untersuchungen zur Anwendbarkeit dieser photochemischen Umwandlung durch und konnten zeigen, dass eine große Vielfalt acider Alkohole in dieser Reaktion eingesetzt werden können und damit die Machbarkeit dieses Konzepts in O‐H‐Funktionalisierungsreaktionen demonstrieren (54 Beispiele, bis zu 98 % Ausbeute). [ABSTRACT FROM AUTHOR]

The objective of this in vitro study was to evaluate the influence of remineralizing agents on the surface roughness of eroded tooth enamel. Forty incisive bovines were selected and sectioned to obtain specimens of 4mm X 4mm, resulting in a surface area of 16,00mm², with a thickness of 2.50mm. The specimens were immersed in lemon juice, twice a day, over 5 days, and randomly divided into the following 4 groups: G1 = No treatment; G2 = 1.23% APF; G3 = Fluoride Varnish 5% and G4 = Regenerated. The surface roughness of the specimens was analyzed by means of confocal laser scanning microscopy. The obtained data were submitted to ANOVA after attend the homogeneity (Levene´s) and normality tests (Kolmogorov-Smirnov). All tests were statistically significant at 5% (α=0.05). The results showed that there was no statistically significant difference on the enamel roughness surface area between groups in the experimental region and the founded values were higher at the experimental when compared to the control region, however, without differences between the groups in each region. It was concluded that the remineralizing agents were not able to reduce the surface roughness of the studied groups. [ABSTRACT FROM AUTHOR]

In various nickel(II) salicylaldiminato ethylene polymerization catalysts, which are a versatile mechanistic probe for substituent effects, longer perfluoroalkyl groups exert a strong effect on catalytic activities and polymer microstructures compared to the trifluoromethyl group. This effect is accounted for by a reduced electron density on the active sites, and is also supported by electrochemical studies. Thus, β‐hydride elimination, the key step of chain transfer and branching pathways, is disfavored while chain‐growth rates are enhanced. This enhancement occurs to an extent that enables living polymerizations in aqueous systems to afford ultra‐high‐molecular‐weight polyethylene for various chelating salicylaldimine motifs. These findings are mechanistically instructive as well as practically useful for illustrating the potential of perfluoroalkyl groups in catalyst design. [ABSTRACT FROM AUTHOR]

An asymmetric palladium and copper co‐catalyzed Heck/Sonogashira reaction between o‐iodoacrylanilides and terminal alkynes to synthesize chiral oxindoles was developed. In particular, a wide range of CF3‐substituted o‐iodoacrylanilides reacted with terminal alkynes, affording the corresponding chiral oxindoles containing trifluoromethylated quaternary stereogenic centers in high yields with excellent enantioselectivities (94–98 % ee). This asymmetric Heck/Sonogashira reaction provides a general approach to access oxindole derivatives containing quaternary stereogenic centers including CF3‐substituted ones. [ABSTRACT FROM AUTHOR]

The preparation of acyclic β‐fluoro amines bearing tetrasubstituted fluorine stereocenters is described via a direct Zn/ProPhenol‐catalyzed Mannich reaction. The reaction utilizes branched vinyl or alkynyl α‐fluoro ketones that can be coupled with a range of aryl, heteroaryl, vinyl, or cyclopropyl aldimines in high yield and with excellent diastereo‐ (up to >20:1) and enantioselectivity (up to 99 %). The use of readily cleaved tert‐butoxycarbonyl (Boc) or carboxybenzyl (Cbz) imine protecting groups adds utility to the reaction by allowing for easy access to the free amine products under mild and chemoselective reaction conditions. [ABSTRACT FROM AUTHOR]

Stereogenic trifluoromethyl‐substituted carbon centers are highly sought‐after moieties in pharmaceutical and agrochemical discovery. Here, we show that lithiation–borylation reactions of 2‐trifluoromethyl oxirane give densely functionalized and highly versatile trifluoromethyl‐substituted α‐tertiary boronic esters. The intermediate boronate complexes undergo the desired 1,2‐rearrangement of the carbon‐based group with complete retentive stereospecificity, a process that was only observed in non‐polar solvents in the presence of TESOTf. Although the trifluoromethyl group adversely affects subsequent transformations of the α‐boryl group, Zweifel olefinations provide trifluoromethyl‐bearing quaternary stereocenters substituted with alkenes, alkynes and ketones. [ABSTRACT FROM AUTHOR]

Ultra‐high‐molecular‐weight (UHMW) polymers display outstanding properties and hold potential for wide applications. However, their precise synthesis remains challenging. Herein, we developed a novel reversible‐deactivation radical polymerization based on the strong and selective fluorine–fluorine interaction, allowing chain‐transfer agents to spontaneously differentiate into two groups that take charge of the chain growth and reversible deactivation of the growing chains, respectively. This method enables dramatically improved livingness of propagation, providing UHMW polymers with a surprisingly narrow molecular weight distribution (Đ≈1.1) from a variety of fluorinated (meth)acrylates and acrylamide at quantitative conversions under visible‐light irradiation. In situ chain‐end extensions from UHMW polymers facilitated the synthesis of well‐defined block copolymers, revealing the excellent chain‐end fidelity achieved by this method. [ABSTRACT FROM AUTHOR]

Spectroscopic and biophysical methods for structural determination at atomic resolution are fundamental in studies of biological function. Here we introduce an approach to measure molecular distances in bio‐macromolecules using 19F nuclear spins and nitroxide radicals in combination with high‐frequency (94 GHz/3.4 T) electron–nuclear double resonance (ENDOR). The small size and large gyromagnetic ratio of the 19F label enables to access distances up to about 1.5 nm with an accuracy of 0.1–1 Å. The experiment is not limited by the size of the bio‐macromolecule. Performance is illustrated on synthesized fluorinated model compounds as well as spin‐labelled RNA duplexes. The results demonstrate that our simple but strategic spin‐labelling procedure combined with state‐of‐the‐art spectroscopy accesses a distance range crucial to elucidate active sites of nucleic acids or proteins in the solution state. [ABSTRACT FROM AUTHOR]

Copyright of RGO: Revista Gaúcha de Odontologia is the property of RGO: Revista Gaucha de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fluoride toothpastes have long been recommended as part of the measures to prevent dental caries. Controversial findings suggest that an inappropriate use of this type of dentifrices can significantly contribute to the total intake of fluoride by children younger than 3 years, being one of the reasons why they have been linked to the development of dental fluorosis. The cost-benefit relationship of using fluoride dentifrices in children has been controversial and has allowed the evolution of concepts that reinforce the recommendations to use them. This topic review discusses some aspects that determine the preventive potential of fluoride toothpastes, the academic recommendations to use them, the various policies in Latin American countries on the issue, and a brief description of the availability of products in the Colombian market. This article seeks to contribute to a better understanding of this issue and therefore to a better orientation of patients.

The objectives of this study were to characterize and evaluate the physicochemical properties of 10 cassava breeding genotypes developed by cassava crop improvement of (Institut Pertanian Bogor) IPB research group. The physicochemical characterization was performed by measuring water content, ash, protein, fat, carbohydrate, pasta (pasting properties), starch total, amylose content, and whiteness. The results showed that each genotype has different chemical content and gelatinization properties. The highest water content (11.48 ± 0.12 %) was found in genotype V4D0 (variant genotype Malang 4), ash (1.83 ± 0.02 %) in V5D2 (1) (A variant of genotype Malang 4-1), fat (1.62 ± 0.93 %) and protein (4.73 ± 0.19 %) in V3D1 (1) (variant UJ 5-1). Genotype V1D1-1(1) (A variant of genotype Ratim-1) has the highest amylose (23.33 ± 0.04 %) and the lowest ones (13.13 ± 0.48 %) was found in genotype V2D1-1(3). Genotype V2D0 has the highest total starch (88.67 %) and the lowest (74.3%) was obtained in V5D2 (1). The highest whiteness value was measured in genotype V1D0 i.e. 93.13 %. For pasting properties testing, it was measured that genotype V2D1-1 (3) had the lowest peak viscosity i.e 4,006 cP and the high of end of viscosity occurred 2,592 cP in genotype V4D2-1 (2) (A variant of genotype Adira 4-1), were correlated with high amylose content owned flour is 22.03 ± 0.25%. ABSTRAK Penelitian ini bertujuan untuk mengkarakterisasi dan mengevaluasi sifat fisikokimia 10 genotipe ubi kayu hasil pemuliaan team crop improvement ubi kayu Institut Pertanian Bogor (IPB). Karakterisasi fisikokimia dilakukan dengan cara melakukan analisis kadar air, abu, protein, lemak, karbohidrat, pasta (pasting properties), total pati, kadar amilosa, dan derajat putih. Dari hasil karakterisasi diperoleh bahwa setiap genotipe ubi kayu memiliki kandungan kimia dan sifat gelatinisasi yang berbeda-beda. Kadar air tertinggi dimiliki genotipe V4D0 (Genotipe Malang 4) 11,48 ± 0,12 % , kadar abu dan lemak tertinggi adalah genotipe (V5D2 (1) (Varian dari genotipe Malang 4-1) yaitu 1,83 % ± 0,02 dan 1,62 ± 0,93 % serta kadar protein tertinggi adalah V3D1 (1) (Varian UJ 5-1) 4,73 ± 0,19 %. Genotipe V1D1-1 (1) (Varian dari genotipe Jame-1) memiliki kadar amilosa tertinggi yaitu 23,33 ± 0,04 % sedangkan yang terendah dihasilkan oleh genotipe V2D1-1 (3) (Varian dari genotipe Ratim-1) yaitu 13,13 ± 0,48 %. Genotipe V2D1-1 (3) (Varian genotipe Ratim-1) memiliki viskositas puncak terendah yaitu 4.006 cP berkorelasi positif dengan kandungan amilosa paling rendah yang dimilikinya. Viskositas akhir yang tinggi terjadi pada genotipe V4D2-1(2) (Varian genotipe Adira 4-1) yaitu 2.592 cP yang berkorelasi dengan tingginya kandungan amilosa yang dimiliki tepung tersebut yaitu 22,03 ± 0,25 %.

Resumo Introdução O flúor possui eficácia no combate e na prevenção à cárie dentária, o que justifica sua adição na água de abastecimento público, no sal, em géis, soluções para bochechos, vernizes, dentifrícios e materiais restauradores. O objetivo do presente estudo foi avaliar a fluoretação da água potável para consumo humano no abastecimento público, em um município do Rio Grande do Sul, por meio de análise das amostras de água. Métodos O estudo tem um delineamento descritivo de 121 amostras de água fluoretada, coletadas mensalmente no ano de 2013, em diferentes bairros da zona urbana do município. Resultados Os níveis estavam aceitáveis em 39,7% das amostras, pois 60,3% apresentaram-se abaixo do ideal, e somente 21,4% das amostras ofereceram a melhor combinação risco-benefício para a população (0,65-0,94mg/L de F). Conclusão Concluiu-se que os níveis de concentração de flúor observados nas amostras de água não se mantiveram constantes no período, estando em desacordo com a legislação vigente. Esses dados podem estar correlacionados com a alta prevalência de cárie dentária encontrada na população em estudos municipais.