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Single crystal diamond (SCD) is a promising material to satisfy emerging requirements of high-demand fields, such as microelectronics, beta batteries and wide-spectrum optical communication systems, due to its excellent optical characteristics, elevated breakdown voltage, high hardness and superior thermal conductivity. For such applications, it is essential to study the optically active defects in as-grown diamonds, namely three-dimensional defects (such as stacking faults and dislocations) and the inherent defects arising from the cultivation method. This paper reports the growth of SCD films on a commercial HPHT single-crystal diamond seed substrate using a 2.45 GHz microwave plasma-assisted chemical vapor deposition (MWPACVD) technique by varying the methane (CH4) gas concentration from 6 to 12%, keeping the other parameters constant. The influence of the CH4 concentration on the properties, such as structural quality, morphology and thickness, of the highly oriented SCD films in the crystalline plane (004) was investigated and compared with those on the diamond substrate surface. The SCD film thickness is dependent on the CH4 concentration, and a high growth rate of up to 27 µm/h can be reached. Raman spectroscopy, high-resolution X-ray diffractometry (HRXRD), scanning electron microscopy (SEM), surface profilometry and optical microscopic analyses showed that the produced homoepitaxial SCD films are of good quality with few macroscopic defects.

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The growing need for increasingly miniaturized devices has placed high importance and demands on nanofabrication technologies with high-quality, low temperatures, and low-cost techniques. In the past few years, the development and recent advances in atomic layer deposition (ALD) processes boosted interest in their use in advanced electronic and nano/microelectromechanical systems (NEMS/MEMS) device manufacturing. In this context, non-thermal plasma (NTP) technology has been highlighted because it allowed the ALD technique to expand its process window and the fabrication of several nanomaterials at reduced temperatures, allowing thermosensitive substrates to be covered with good formability and uniformity. In this review article, we comprehensively describe how the NTP changed the ALD universe and expanded it in device fabrication for different applications. We also present an overview of the efforts and developed strategies to gather the NTP and ALD technologies with the consecutive formation of plasma-assisted ALD (PA-ALD) technique, which has been successfully applied in nanofabrication and surface modification. The advantages and limitations currently faced by this technique are presented and discussed. We conclude this review by showing the atomic layer etching (ALE) technique, another development of NTP and ALD junction that has gained more and more attention by allowing significant advancements in plasma-assisted nanofabrication.

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The chemical, structural, morphological, and optical properties of Al-doped TiO2 thin films, called TiO2/Al2O3 nanolaminates, grown by plasma-enhanced atomic layer deposition (PEALD) on p-type Si <100> and commercial SLG glass were discussed. High-quality PEALD TiO2/Al2O3 nanolaminates were produced in the amorphous and crystalline phases. All crystalline nanolaminates have an overabundance of oxygen, while amorphous ones lack oxygen. The superabundance of oxygen on the crystalline film surface was illustrated by a schematic representation that described this phenomenon observed for PEALD TiO2/Al2O3 nanolaminates. The transition from crystalline to amorphous phase increased the surface hardness and the optical gap and decreased the refractive index. Therefore, the doping effect of TiO2 by the insertion of Al2O3 monolayers showed that it is possible to adjust different parameters of the thin-film material and to control, for example, the mobility of the hole-electron pair in the metal-insulator-devices semiconductors, corrosion protection, and optical properties, which are crucial for application in a wide range of technological areas, such as those used to manufacture fluorescence biosensors, photodetectors, and solar cells, among other devices.

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PURPOSE: To diagnose ankyloglossia in newborns and compare two lingual frenulum assessment instruments. METHODS: This cross-sectional study was carried out in Recife, Pernambuco, Brazil, in 2018, with 147 mothers/newborns aged up to 30 days. The Bristol Tongue Assessment Tool and the Lingual Frenulum Evaluation Protocol for Infants were the instruments used. Sociodemographic data were also recorded. The two ankyloglossia diagnostic methods were compared using the McNemar test, obtaining the kappa agreement value and the confidence interval. RESULTS: Ankyloglossia was present in 4.8% when diagnosed with the Bristol Tongue Assessment Tool, and in 17.0% with the Tongue-Tie Test. Regarding sex, 53.1% of the newborns were males and 46.9% were females; however, there was no association between ankyloglossia and the newborn's sex in either of the assessment methods. CONCLUSION: The ankyloglossia diagnosis in newborns varied depending on the assessment instrument used.

OBJETIVO: Diagnosticar a anquiloglossia em recém-nascidos, comparando dois instrumentos de avaliação do frênulo lingual. MÉTODO: Tratou-se de um estudo transversal, realizado em Recife, PE, Brasil no ano de 2018, com 147 mães/recém-nascidos com idade de até 30 dias de vida. Foram utilizados o Instrumento Bristol Tongue Assessment Tool (BTAT) e o Protocolo de Avaliação do Frênulo da Língua para Bebês ("Teste da Linguinha"). Dados sociodemográficos também foram anotados. Para a comparação entre os dois métodos de diagnóstico da anquiloglossia, foi utilizado o teste de McNemar e foram obtidos o valor da concordância de Kappa e o respectivo intervalo de confiança. RESULTADOS: A presença de anquiloglossia foi de 4,8%, quando diagnosticada por meio do BTAT, e de 17,0%, quando utilizado o "Teste da Linguinha". Com relação ao sexo, 53,1% dos recém-nascidos eram do sexo masculino e 46,9% do sexo feminino; contudo, não houve associação entre a anquiloglossia e o sexo do recém-nascido nos dois métodos de avaliação. CONCLUSÃO: O diagnóstico da anquiloglossia em recém-nascidos variou em função do instrumento de avaliação utilizado.

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This work proposes the use of a dielectric barrier discharge (DBD) reactor operating at atmospheric pressure (AP) using air and sub-atmospheric pressure (SAP) using air or argon to treat polyamide 6.6 (PA6.6) fabrics. Here, plasma dosages corresponding to 37.5 kW·min·m-2 for AP and 7.5 kW·min·m-2 for SAP in air or argon were used. The hydrophilicity aging effect property of untreated and DBD-treated PA6.6 samples was evaluated from the apparent contact angle. The surface changes in physical microstructure were studied by field emission scanning electron microscopy (FE-SEM). To prove the changes in chemical functional groups in the fibers, Fourier transform infrared spectroscopy (FTIR) was used, and the change in surface bonds was evaluated by energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). In addition, the whiteness effect was investigated by the color spectrophotometry (Datacolor) technique. The results showed that the increase in surface roughness by the SAP DBD treatment contributed to a decrease in and maintenance of the hydrophilicity of PA6.6 fabrics for longer. The SAP DBD in air treatment promoted an enhancement of the aging effect with a low plasma dosage (5-fold reduction compared with AP DBD treatment). Finally, the SAP DBD treatment using argon functionalizes the fabric surface more efficiently than DBD treatments in air.

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A search of the recent literature reveals that there is a continuous growth of scientific publications on the development of chemical vapor deposition (CVD) processes for silicon carbide (SiC) films and their promising applications in micro- and nanoelectromechanical systems (MEMS/NEMS) devices. In recent years, considerable effort has been devoted to deposit high-quality SiC films on large areas enabling the low-cost fabrication methods of MEMS/NEMS sensors. The relatively high temperatures involved in CVD SiC growth are a drawback and studies have been made to develop low-temperature CVD processes. In this respect, atomic layer deposition (ALD), a modified CVD process promising for nanotechnology fabrication techniques, has attracted attention due to the deposition of thin films at low temperatures and additional benefits, such as excellent uniformity, conformability, good reproducibility, large area, and batch capability. This review article focuses on the recent advances in the strategies for the CVD of SiC films, with a special emphasis on low-temperature processes, as well as ALD. In addition, we summarize the applications of CVD SiC films in MEMS/NEMS devices and prospects for advancement of the CVD SiC technology.

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Background: Ankyloglossia is characterized by abnormal tongue movements that can possibly interfere with breastfeeding due to incorrect latching, pain, nipple fissure, and ineffective suction. Objective: To determine the prevalence of ankyloglossia in newborns and its association with exclusive breastfeeding and early breastfeeding difficulties. Materials and Methods: This is an analytical cross-sectional study conducted in seven public maternity hospitals in the city of Recife, PE, Brazil. The study sample consisted of 822 mothers/newborns of both genders. The diagnosis of ankyloglossia was confirmed by comparing two previously standardized and validated lingual frenulum assessment tools. Information on the mother's socioeconomic profile and breastfeeding difficulties were also collected. The data were analyzed using bivariate and multivariate logistic regression models. Results: The prevalence of ankyloglossia was 2.6% when using the Bristol Tool and 11.7% with the Assessment Tool for Lingual Frenulum Function (Neonatal Tongue Screening Test-NTST). The agreement between the two assessment tools was 2.2%, with a significant difference between them (p < 0.001). There was an association between the occurrence of ankyloglossia and breastfeeding difficulties (odds ratio = 1.99), but no association with exclusive breastfeeding practice was found. Conclusions: The diagnostic tools used herein revealed different prevalence rates of ankyloglossia in newborns. This condition was associated with breastfeeding difficulties, and the NTST was more effective in determining such an association.

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ABSTRACT Purpose: to investigate the scientific evidence, in the literature, of the relationship between ankyloglossia and breastfeeding difficulties. Methods: an integrative review of the literature. The MEDLINE and PubMed databases were searched, using the following descriptors in combination: "ankyloglossia", "newborn" and "breastfeeding". The searches included articles published between 2014 and 2019, in Portuguese, English and Spanish. Original articles demonstrating an association between ankyloglossia and breastfeeding issues were selected. Results: a total of 31 articles was fully read in the analysis, 22 of which were excluded and 9 included in the review. There was a diversity of instruments used for the diagnosis of ankyloglossia. In four studies, no standardized evaluation instrument was used for the diagnosis of ankyloglossia, which may limit the analysis of the results. However, most studies have evidenced a possible influence of ankyloglossia on breastfeeding. According to the studies, babies with altered lingual frenulum were more likely to experience difficulties in sucking, showing early weaning, which shows the importance of neonatal screening as a routine protocol in maternity hospitals for the cases of ankyloglossia. Conclusions: ankyloglossia may be related to impaired breastfeeding. The standardization of instruments for the diagnosis of ankyloglossia is necessary to improve the evidence in future research.

RESUMO Objetivo: investigar as evidências científicas na literatura sobre a relação entre a anquiloglossia e as dificuldades no aleitamento materno. Métodos: tratou-se de uma revisão integrativa. Foram realizadas buscas nas bases de dados Medline e Pubmed, utilizando os descritores em associação: "anquiloglossia", "recém-nascido" e "amamentação", entre 2014 e 2019, em português, inglês e espanhol. Foram selecionados artigos originais que relacionassem a anquiloglossia aos problemas de amamentação. Resultados: trinta e um artigos foram analisados pelo texto lido na íntegra, dentre os quais 22 foram excluídos e 09 selecionados para a revisão. Houve uma diversidade de instrumentos utilizados para o diagnóstico da anquiloglossia. Em quatro estudos não foi utilizado nenhum instrumento de avaliação padronizado para o diagnóstico da anquiloglossia, o que pode limitar a análise dos resultados. No entanto, a maioria dos estudos evidenciou a possível interferência da anquiloglossia na amamentação. De acordo com as publicações, bebês com frênulo lingual alterado apresentaram maiores chances de apresentar dificuldades na sucção e desmame precoce, o que demonstra a importância da triagem neonatal como rotina nas maternidades para os casos de anquiloglossia. Conclusões: a anquiloglossia pode estar relacionada com prejuízos na amamentação e a padronização dos instrumentos para diagnóstico da anquiloglossia é necessária para melhorar as evidências nas futuras pesquisas.

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RESUMO A falta de água é um problema que afeta muitas regiões do nosso planeta, especialmente ilhas e locais de clima muito seco. Especialistas dizem que essa situação irá se agravar e que, em 2025, cerca de 1,8 bilhão de pessoas sofrerão com essa escassez. Embora métodos tradicionais de dessalinização sejam alternativas bem conhecidas e implantadas para obtenção de água potável, eles não são sustentáveis ambientalmente, porque são geralmente supridos por combustíveis não renováveis, cuja queima intensifica o efeito estufa, trazendo desequilíbrios ao meio ambiente. Outra opção que vem sendo desenvolvida ao longo dos anos é a dessalinização por energia solar. Como se trata de uma forma de energia limpa, abundante e renovável, esse método já é muito indicado em regiões isoladas, de baixa e média demanda. Algumas técnicas são apresentadas neste trabalho, que foca o método de dessalinização por umidificação e desumidificação (DSUD). Essa técnica tem se mostrado a mais eficiente, devido ao seu reaproveitamento de energia. Há ainda muito o que melhorar para viabilizar a sua implantação em grande escala, principalmente em termos de produção de água, energia específica requerida e custo específico de produção de água. Entretanto, a DSUD já se mostrou uma técnica sustentável, promissora, de custo razoável e funcionamento simples. Dessa forma, os autores incentivam maiores investimentos em pesquisas no Brasil na área de dessalinização solar e aproveitamento dos rejeitos do processo, visando à produção de água purificada nas regiões brasileiras que têm deficiência em água potável.

ABSTRACT The lack of water is a problem that affects many regions in our planet, specially in very dry places and isles. Experts say that this situation will worsen, and that by 2025 about 1.8 billion people will suffer with water scarcity. Although traditional desalination methods are well-known and implemented alternatives to obtain fresh drinking water, they are not environmentally sustainable, because they are generally supplied by non-renewable fuels, whose combustion intensifies the greenhouse effect, causing disequilibrium to the environment. Another option that has been developed along the years is the desalination by solar energy. Since it is a clean, abundant and renewable type of energy, it is already a good option to isolated regions, whose demand is low or medium. Some technics are shown in this work, which focuses on the humidification-dehumidification desalination method. This technique has shown to be the most efficient one, due to its energy reuse. There is still a long way to go in order to make it viable in large scale, especially in terms of water production, specific energy requirement and specific cost of water production. However, solar desalination by humidification-dehumidification has proven to be a sustainable, promising technic which is reasonably costly and simple to operate. Therefore, the authors encourage more investments in researches in Brazil in the area of solar desalination and use of its rejects, aiming at the production of fresh water in Brazilian regions lacking it.

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Many strategies have been developed for the synthesis of silicon carbide (SiC) thin films on silicon (Si) substrates by plasma-based deposition techniques, especially plasma enhanced chemical vapor deposition (PECVD) and magnetron sputtering, due to the importance of these materials for microelectronics and related fields. A drawback is the large lattice mismatch between SiC and Si. The insertion of an aluminum nitride (AlN) intermediate layer between them has been shown useful to overcome this problem. Herein, the high-power impulse magnetron sputtering (HiPIMS) technique was used to grow SiC thin films on AlN/Si substrates. Furthermore, SiC films were also grown on Si substrates. A comparison of the structural and chemical properties of SiC thin films grown on the two types of substrate allowed us to evaluate the influence of the AlN layer on such properties. The chemical composition and stoichiometry of the samples were investigated by Rutherford backscattering spectrometry (RBS) and Raman spectroscopy, while the crystallinity was characterized by grazing incidence X-ray diffraction (GIXRD). Our set of results evidenced the versatility of the HiPIMS technique to produce polycrystalline SiC thin films at near-room temperature by only varying the discharge power. In addition, this study opens up a feasible route for the deposition of crystalline SiC films with good structural quality using an AlN intermediate layer.