Ler no ecrã: contributo para uma reflexão sobre estratégias de ensino da leitura na aula de Português

Resumo: A Escola assume, hoje, um papel cada vez mais ativo na formação dos (ciber)leitores, sendo chamada a reconfigurar um conjunto pré-existente de práticas em literacia onde predomina o texto impresso para um universo digital complexo, no qual o ecrã tem primazia. Assim, neste artigo procuraremos: (1) reforçar o modo como novas práticas em literacia emergem em permanência na nossa sociedade, repercutindo-se no percurso dos leitores em formação; (2) apontar para o modo como a leitura no ecrã de textos diversificados influencia a compreensão leitora, daí retirando ilações no que concerne à construção do percurso do leitor; (3) caracterizar a forma como a leitura online requer o desenvolvimento de um conjunto amplo de estratégias por parte do leitor, para que possa usufruir plenamente do prazer de ler em contexto escolar e extra-escolar. Finalmente, reflectimos criticamente sobre os desafios colocados hoje à Escola, relativamente à implementação e consolidação de percursos de leitura que estejam na base do exercício hodierno da cidadania

Apical Periodontitis Healing Following Treatment is Impacted by Root Canal Sealer Composition: An in Vivo and in Vitro Investigation

Objective: To evaluate the periapical healing following root canal treatment in teeth with apical periodontitis (in vivo) and the cytotoxic potential of root canal sealers in vitro. Material and Methods: Apical periodontitis was induced in 60 dogs' teeth and root canals were filled with Sealapex (40 roots), EndoREZ (40 roots), intracanal dressing (20 roots), or left untreated (20 roots). After 30 and 90 days, histopathological analyses were made. In vitro, J774.1 macrophages were stimulated with root canal sealers extracts, cytotoxicity was assessed using lactate dehydrogenase assay, and qRT-PCR was used to analyze TNF-α gene expression. Results: In vivo, smaller apical periodontitis and lower inflammatory cell infiltrate were found in teeth treated with Sealapex compared to EndoREZ. In vitro, EndoREZ was cytotoxic and induced TNF-α gene expression by macrophages differently from Sealapex. Conclusion: Sealapex allowed improved tissue repair following root canal treatment in teeth with apical periodontitis compared to EndoREZ. Synthesis of TNF-α induced by LPS was enhanced by EndoREZ, whereas Sealapex prevented pro-inflammatory gene expression

Sodium Hypochlorite as Fluorotic Dentin Pretreatment of Two-Step Self-Etch Adhesive with Silver Nanoparticle: Atomic Force Microscope and Adhesive Microtensile Bond Strength Evaluation

The objective of this work was to evaluate the effect of pretreatment with commercial sodium hypochlorite, 5.25%, with a self-etch adhesive (Optibond Versa) in its original formula and with the incorporation of silver nanoparticles (NaAg) on fluorotic dentin. 240 human molars were classified according to fluorosis severity with Thylstrup-Fejerskov Index (TFI) and subdivided into three study subgroups according to the adhesive technique: (1) self-etch (SE) control subgroup; (2) NaOCl/SE subgroup; (3) NaOCl/SE + NaAg subgroup. The nanostructural characteristics were observed by AFM, μTBS was tested, and hybrid layer formation was observed by SEM. One-way analyses of variance (ANOVA) and Tukey-Kramer post hoc tests were used. No statistically significant differences were found in roughness values in any of the subgroups and subgroups studied. Remnants of smear layer were detected in areas devoid of resin tags in SEM images of samples bonded with subgroup 2, in contrast to subgroup 3. No statistically significant difference between any of the results was found in μTBS and a greater number of adhesive failures were observed. The results show that the pretreatment technique of 5.25% NaOCl and the incorporation of NaAg to the self-adhesive system do not produce a surface more adequate for a better adhesion

Margarita de Sossa, Sixteenth-Century Puebla de los Ángeles, New Spain (Mexico)

Margarita de Sossa’s freedom journey was defiant and entrepreneurial. In her early twenties, still enslaved in Portugal, she took possession of her body; after refusing to endure her owner’s sexual demands, he sold her, and she was transported to Mexico. There, she purchased her freedom with money earned as a healer and then conducted an enviable business as an innkeeper. Sossa’s biography provides striking insights into how she conceptualized freedom in terms that included – but was not limited to – legal manumission. Her transatlantic biography offers a rare insight into the life of a free black woman (and former slave) in late sixteenth-century Puebla, who sought to establish various degrees of freedom for herself. Whether she was refusing to acquiesce to an abusive owner, embracing entrepreneurship, marrying, purchasing her own slave property, or later using the courts to petition for divorce. Sossa continued to advocate on her own behalf. Her biography shows that obtaining legal manumission was not always equivalent to independence and autonomy, particularly if married to an abusive husband, or if financial successes inspired the envy of neighbors

Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF

M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Comparison of physicochemical properties of an ionomer-based and two silicon-based endodontic sealers.

Este estudo avaliou, in vitro, tempo de endurecimento (TE), alteração dimensional (AD), solubilidade (Sl) e radiopacidade (Rp) dos cimentos AH Plus, GuttaFlow, RoekoSeal, Activ GP, Endofill e um cimento experimental à base de MTA. Para estes testes o cimentos Activ GP foi manipulado na relação pó/líquido de 28 mg para 50 µL de líquido. Para determinar o TE, moldes (10 X 2 mm) foram preenchidos com cimento e, decorridos 150 s, os cimentos foram testados com agulha tipo Gillmore (100 g), a cada 60 s, até que não houvesse marcas na superfície. Para o teste de alteração dimensional, 5 corpos-de-prova cilíndricos (3,58 x 3,0 mm) foram obtidos. Após a mensuração de seus comprimentos por meio de parquímetro digital, foram imersos em 2,24 mL de água destilada e deionizada por 30 dias e mensurados novamente. Para o teste de Sl, foram obtidos 10 corpos-de-prova (1,5 X 7,75 mm). Após serem pesados, dois a dois, foram imersos em 7,5 mL de água destilada por 7 dias e pesados novamente, determinando-se a perda percentual da massa. Os líquidos de imersão foram submetidos à espectrometria para detecção dos íons Ca2+, K+, Ni2+, Pb2+, Zn2+, Ag+. Para a Rp, 5 placas de acrílico com 4 perfurações (5 X 1 mm) foram preenchidas com cimento e, ao lado de escada de alumínio padronizada, foram radiografadas com distância foco-objeto de 30 cm e exposição de 0,2 s. A densidade radiográfica foi determinada por meio do Digora for Windows 1.51. Os resultados mostraram que os cimentos GuttaFlow e RoekoSeal estavam de acordo com a Especificação n° 57 da ANSI/ADA para os testes de TE e Rp. Em relação a ED, somente o Guttaflow estava de acordo com esta Especificação. Em relação à Sl, somente o cimento Activ GP (11,80%) não atendeu os padrões exigidos pela ANSI/ADA. A espectrometria de absorção atômica mostrou que o cimento Activ GP apresentou liberação expressiva de ions Ca2+. A liberação de ions Zn2+ foi evidenciada no cimento Activ GPl. Concluiu-se que somente cimento Guttaflow atendeu às exigências da ANSI/ADA em relação à radiopacidade, estabilidade dimensional e solubilidade.This study evaluated, in vitro, the setting time (ST), dimensional alteration (DA), solubility (Sl) and radiopacity (Rp) of the sealers AH Plus, GuttaFlow, RoekoSeal, Activ GP, Endofill and a MTA-based experimental sealer. For these tests, the sealer Activ GP was prepared using a powder/liquid mixing ratio of 28 mg to 50 µL of liquid. In order to determine the ST, moulds (10 x 2 mm) were filled with sealer. After 150 s, the sealers were tested with a Gilmore needle (100 g) at 60-s intervals until no marks were visible on the material surface. For the DA test, 5 cylindrical specimens (3.58 x 3.0 mm) were obtained. After having their dimensions checked with a digital caliper, the specimens were stored in 2.24 mL distilled deionized water for 30 days and their dimensions were rechecked. For the Sl test, 10 specimens (1.5 x 7.75 mm) were obtained. After being weighed in pairs, the specimens were stored in 7.5 mL distilled water for 7 days and reweighed to determine the percent mass loss. The liquids in which the specimens were immersed were subjected to spectrometry for detection of ions Ca2+, K+, Na+, Ni2+, Pb2+, Zn2+and Ag+. For the Rp test, 5 acrylic plates with 4 perforations (5 x 1 mm) were filled with sealer and were radiographed near to a graduated aluminum stepwedge with 30-cm focus-object distance and 0.2-s exposure time. The radiographic density was determined using the Digora for Windows 1.51 software. The results showed that GuttaFlow and RoekoSeal were in compliance with the ANSI/ADAs specification no. 57 for the TE and Rp tests. Regarding DA, only GuttaFlow was in accordance with this specification. Regarding Sl, only Activ GP (11.80%) did not meet the ANSI/ADAs requirements. The atomic absorbance spectrometry showed that the sealer Activ GP presented significant release of Ca2+. Release of Zn2+ ions was observed for the sealer Activ GP. In conclusion, only the sealer Guttaflow met the ANSI/ADAs requirements for radiopacity, dimensional stability and solubility

Apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing on root canal disinfection in dog teeth

Objective. The aim of this study was to compare in vivo the efficacy of 2 root canal disinfection techniques (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dog teeth with apical periodontitis. Study design. Two groups of root canals with pulp necrosis and apical periodontitis were evaluated according to the disinfection technique: group 1: apical negative pressure irrigation (EndoVac system); and group 2: apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. The first sample (S1) was collected after lesions were radiographically visible, and the second sample (S2) was collected after apical negative pressure irrigation (group 1) or conventional irrigation/triantibiotic dressing (group 2). All samples were seeded in a culture medium for anaerobic bacteria. Colony-forming unit counts were analyzed statistically by the Mann-Whitney test (alpha = .05). Results. Microorganisms were present in 100% of canals of both groups in S1. In S2, microorganisms were absent in 88.6% of group 1`s canals and 78.28% of group 2`s canals. There was no significant difference between the groups in either S1 (P = .0963) or S2 (P = .0566). There was significant (P < .05) bacterial reduction from S1 to S2 in both groups. Conclusion. In immature teeth with apical periodontitis, use of the EndoVac system can be considered to be a promising disinfection protocol, because it provided similar bacterial reduction to that of apical positive pressure irrigation (conventional irrigation) plus intracanal dressing with the triantibiotic paste, and the use of intracanal antibiotics might not be necessary. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e42-e46

Efectividad de tres localizadores apicales electrónicos para determinar la longitud radicular de trabajo.

The aim of this study was to evaluate in vivo the accuracy of three electronic apex locators (EALs) in determining working length (WL) using hand files and a wear technique. Thirty two premolars that were completely formed apically and that were scheduled for extraction for orthodontic reasons from patients between ages of 15 and 20 years old were included. Electronic measurement of WL was performed using the EAL according to the manufacturer’s instructions. The following three EAL were used: A. Root ZX II; B. Raypex 5, and C. Propex II. There were significant difference (p = 0,0002) when comparing median differences among the three EAL. Statistical analysis revealed significant differences between Root ZX II vs. Raypex 5 and Root ZX II vs. Propex II (p = 0,0044; p = 0,0002), while between Raypex 5 and Propex II, there were no statistically significant differences with respect to the accuracy of the EAL in determining WL (p = 0,1087). The present findings suggest that Root ZX II presented the highest agreement rate for determining the final WL.El objetivo del presente estudio fue evaluar in vivo la exactitud de tres localizadores apicales electrónicos (LAEs) para determinar la longitud de trabajo (LT) usando instrumentos manuales y una técnica de desgaste. Treinta y dos premolares con formación apical completa e indicados para extracción por razones ortodóncicas de pacientes de edad entre 15 y 20 años fueron incluidos en el estudio. Se usaron tres LAE; A. Root ZX II; B. Raypex 5, y C. Propex II. Se encontraron diferencias significativas (p = 0,0002) cuando se compararon las medianas entre los tres LAE. El análisis mostró diferencias entre Root ZX II vs. Raypex 5 y Root ZX II vs. Propex II (p = 0,0044; p = 0,0002), mientras que entre Raypex 5 y Propex II, no se encontraron diferencias estadísticamente significativas en la determinación de la LT (p = 0,1087). Los presentes hallazgos sugieren que Root ZX II mostró la mayor exactitud para determinar la LT final

Effectiveness of three electronic apex locators to determine root canal working length

The aim of this study was to evaluate in vivo the accuracy of three electronic apex locators (EALs) in determining working length (WL) using hand files and a wear technique. Thirty two premolars that were completely formed apically and that were scheduled for extraction for orthodontic reasons from patients between ages of 15 and 20 years old were included. Electronic measurement of WL was performed using the EAL according to the manufacturer’s instructions. The following three EAL were used: A. Root ZX II; B. Raypex 5, and C. Propex II. There were significant difference (p = 0,0002) when comparing median differences among the three EAL. Statistical analysis revealed significant differences between Root ZX II vs. Raypex 5 and Root ZX II vs. Propex II (p = 0,0044; p = 0,0002), while between Raypex 5 and Propex II, there were no statistically significant differences with respect to the accuracy of the EAL in determining WL (p = 0,1087). The present findings suggest that Root ZX II presented the highest agreement rate for determining the final WL.El objetivo del presente estudio fue evaluar in vivo la exactitud de tres localizadores apicales electrónicos (LAEs) para determinar la longitud de trabajo (LT) usando instrumentos manuales y una técnica de desgaste. Treinta y dos premolares con formación apical completa e indicados para extracción por razones ortodóncicas de pacientes de edad entre 15 y 20 años fueron incluidos en el estudio. Se usaron tres LAE; A. Root ZX II; B. Raypex 5, y C. Propex II. Se encontraron diferencias significativas (p = 0,0002) cuando se compararon las medianas entre los tres LAE. El análisis mostró diferencias entre Root ZX II vs. Raypex 5 y Root ZX II vs. Propex II (p = 0,0044; p = 0,0002), mientras que entre Raypex 5 y Propex II, no se encontraron diferencias estadísticamente significativas en la determinación de la LT (p = 0,1087). Los presentes hallazgos sugieren que Root ZX II mostró la mayor exactitud para determinar la LT final