In recent years, there has been an increased interest in understanding the enzymatic mechanism of glycosidases resorting mostly to DFT and DFT/MM calculations. However, the performance of density functionals (DFs) is well known to be system and property dependent. Trends drawn from general studies, despite important to evaluate the quality of the DFs and to pave the way for the development of new DFs, may be misleading when applied to a single specific system/property. To overcome this issue, we carried out a benchmarking study of 40 DFs applied to the geometry optimization and to the electronic barrier height (EBarrier) and electronic energy of reaction (ER) of prototypical glycosidase‐catalyzed reactions. Additionally, we report calculations with SCC‐DFTB and four semiempirical MO methods applied to the same problem. We have used a universal molecular model for retaining glycosidases, comprising only a 22‐atoms system that mimics the active site and substrate. High accuracy reference geometries and energies were calculated at the CCSD(T)/CBS//MP2/aug‐cc‐pVTZ level of theory. Most DFs reproduce the reference geometries extremely well, with mean unsigned errors (MUE) smaller than 0.05 Å for bond lengths and 3° for bond angles. Among the DFs, wB97X‐D, CAM‐B3LYP, B3P86, and PBE1PBE have the best performance in geometry optimizations (MUE = 0.02 Å). Conversely, semiempirical MO and SCC‐DFTB methods yielded less accurate geometries (MUE between 0.09 and 0.17 Å). The inclusion of D3 correction has a small, but still relevant, influence in the geometry predicted by some DFs. Regarding EBarrier, 11 DFs (MPW1B95, CAM‐B3LYP, M06 ‐ 2X, PBE1PBE, wB97X ‐ D, B1B95, BMK, MN12 – SX, M05, M06, and M11) presented errors below 1 kcal.mol−1, in relation to the reference energy. Most of these functionals belong to the family of hybrid functionals (H‐GGA, HH‐GGA, and HM‐GGA), which shows a positive influence of HF exchange in the determination of EBarrier. The inclusion of D3 correction has not affected significantly the EBarrier and ER. The use of geometries at the accurate but expensive MP2/aug‐cc‐pVTZ level of theory has a small, albeit not insignificant, influence in the EBarrier when compared with energies calculated with geometries determined with the DFs (usually a few tenths of kcal.mol−1, with exceptions). In general, semiempirical MO methods and DFTB are associated with larger errors in the determination of EBarrier, with unsigned errors from 6.9 to 24.7 kcal.mol−1.

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Graphene-based materials (GBMs) have been increasingly explored for biomedical applications. However, interaction between GBMs-integrating surfaces and bacteria, mammalian cells, and blood components, that is, the major biological systems in our body, is still poorly understood. In this study, we systematically explore the features of GBMs that most strongly impact the interactions of GBMs films with plasma proteins and biological systems. Films produced by vacuum filtration of GBMs with different oxidation degree and thickness depict different surface features: graphene oxide (GO) and fewlayer GO (FLGO) films are more oxidized, smoother, and hydrophilic, while reduced GO (rGO) and few-layer graphene (FLG) are less or nonoxidized, rougher, and more hydrophobic. All films promote glutathione oxidation, although in a lower extent by rGO, indicating their potential to induce oxidative stress in biological systems. Human plasma proteins, which mediate most of the biological interactions, adsorb less to oxidized films than to rGO and FLG. Similarly, clinically relevant bacteria, Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, adhere less to GO and FLGO films, while rGO and FLG favor bacterial adhesion and viability. Surface features caused by the oxidation degree and thickness of the GBMs powders within the films have less influence toward human foreskin fibroblasts; all materials allow cell adhesion, proliferation and viability up to 14 days, despite less on rGO surfaces. Blood cells adhere to all films, with higher numbers in less or nonoxidized surfaces, despite none having caused hemolysis (<5%). Unlike thickness, oxidation degree of GBMs platelets strongly impact surface morphology/ topography/chemistry of the films, consequently affecting protein adsorption and thus bacteria, fibroblasts and blood cells response. Overall, this study provides useful guidelines regarding the choice of the GBMs to use in the development of surfaces for an envisioned application. Oxidized materials appear as the most promising for biomedical applications that require low bacterial adhesion without being cytotoxic to mammalian cells.

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Thrombosis and infection are the leading causes of blood-contacting devices (BCD) failure, mainly due to existing biomaterials' poor performance. Poly(2-hydroxyethyl methacrylate) (pHEMA) has excellent hemocompatibility, but the weak mechanical properties...

 100 RESUMO Introdução: O conceito de mulher solo traveller, apesar de recente, tornou-se um segmento turístico relevante. Estas turistas procuram mais do que uma viagem de um lugar para outro. Escolhem ir sozinhas na busca de aventura, independência, sentimento de realização pessoal, individualidade e fuga. Não viajam sozinhas porque não têm escolha ou porque são solitárias. São levadas por motivações específicas e conscientes. Objetivos: Neste trabalho conceptual, são categorizadas motivações de mulheres solo travellers com base na revisão da literatura, a fim de identificar por que as mulheres escolhem viajar sozinhas. O foco deste artigo é explorar a relação entre essas motivações e as suas experiências de viagem fornecendo um modelo conceptual. Métodos Através de uma ampla revisão de literatura centrada no conceito de motivações e experiências turísticas, permitiu-nos organizar determinadas motivações que levam as mulheres a viajar sozinhas e as suas correspondentes experiências como solo travellers. As escalas multidimensionais consideram oito dimensões de motivações: (1) escape, (2) auto-identidade e desenvolvimento, (3) desafio, (4) conexão com outros, (5) aprendizagem, (6) aventura, (7) novo perspetivas de vida, e (8) autonomia; e cinco dimensões de experiência: (1) sensação, (2) sentir, (3) pensar, (4) agir e (5) relacionar-se baseado no modelo Schmitt da experiencia turística (Schmitt,1999). Resultados: Apesar de uma extensa revisão da literatura, há poucos estudos baseados em experiências e motivações de mulheres solo travellers. Conclusões: Ainda que se trate de um mercado pouco explorado e estudado, ganhou inúmeros apoiantes em todo o mundo, traduzindo-se em um impacto expressivo não só em termos sociológicos, mas também na experiência turística. Palavras-chaves:Turismo; Motivações; Women Solo Travel; Experiência. ABSTRACT Introduction:The concept of female solo traveler, despite recent, has become a relevant tourist segment. As tourists, these women are looking for journeys that bring more than a trip from one place to another. They choose to go alone in the pursuit of adventure, independence, feeling of personal fulfillment, individuality and escape. They do not travel alone because they have no choice or because they are loners. They are driven by specific and consciousness motivations. Objective: In this conceptual work, a set of solo travel motivations are categorize based on literature review, to identify why women, choose to travel alone. The focus of this article is to explore the relationship between these motivations with women solo travel experiences providing a conceptual model. Methods: An extensive literature review focusing on the concept of tourism motivations and experiences provide a framework that allows assesses the specific motivations that driven women into travel alone and the corresponding solo traveler experience dimensions. The multi-dimension scales considers eight motivations dimensions: (1) escape, (2) self-identity and development, (3) challenge, (4) connectedness wit...

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Introduction: Arterial hypertension is a complex, multifactorial disease, controlled by genetic and environmental factors.Objective: Evaluate the genetic susceptibility for developing arterial hypertension and its association with the traditional risk factors in the outbreak of this pathology.Material and Methods: Case-control study with 1712 individuals, mean age of 51.0 ± 7.9 years (860 hypertensive patients and 852 controls). Biochemical and traditional risk factors, and genetic variants were evaluated: ACE I/D rs4340, ACE A2350G rs4343, AGT T174M rs4762, AGT M235T rs699 AGTR1 A1166C rs5186, CYP11B2 -344 C/T rs1799998, ADRB1 R389G rs1801253, ADRB2 R16G rs1042713, ADD1 G460W rs4961, SCNN1G G173A rs5718, GNB3 C825T rs5443, ATP2B1 A/G rs2681472, CYP17A1 T/C rs11191548, SLC4A2 C/T rs2303934. The risk of each gene for hypertension was estimated by the dominant, recessive, co-dominant and multiplicative models. By logistic regression, variables associated with hypertension were evaluated. ROC curves were first performed with traditional risk factors and then adding the genetic variants associated with hypertension. Data were analyzed by SPSS for Windows 19.0 and MedCalc v. 13.3.3.0.Results: The genetic variants ADD1 G460W, GNB3 C825T, ACE I/D, ACE A2350G were associated with hypertension. ROC curve with traditional risk factors and these variants showed an increase in the predictive capacity of hypertension (p = 0.018).Discussion: According to the results of our study, the genetic variants found to be associated with hypertension were: ACE I/D rs4340, ACE A2350G rs4343, ADD1 G460W rs4961 and GNB3 C825T rs5443. The first two variants are associated with hypertension by interfering with the renin-angiotensin-aldosterone system, which plays an important role in regulating blood pressure. It should be noted that genes encoding the components of renin-angiotensin-aldosterone system are natural candidates for the development and progression of hypertension. In our population alpha-aducin polymorphism (ADD1 G460W rs4961) was also associated with hypertension. In a Portuguese population, known to have high salt intake, it makes sense that this polymorphism which is relevant in salt and water management may consequently be relevant in the onset of hypertension. The genetic variant GNB3 C825T rs5443 that affects intracellular signalling was also found to be a strong risk candidate for hypertension. Initially, with the elaboration of the ROC curve and calculation of the AUC using only with traditional risk factors and later by adding the variants ADD1 G460W, GNB3 C825T, ACE I/D and ACE A2350G to the traditional risk factors, we verified that genetic polymorphisms increased the predictive risk of hypertension, when compared to the risk given only by traditional risk factors, with statistical significance (p = 0.018). This suggests that hypertension is a multifactorial disease that results from the interaction of environmental, genetic and lifestyle factors that interact with each other and lead to the advent of this important pathology.Conclusion: In our study, the hypertension-associated polymorphisms are linked to the renin-angiotensin-aldosterone axis (ACE I/D, ACE A2350G), as well as to salt and water management (ADD1 G460W, GNB3 C825T). Through a multivariate analysis, it was concluded that these two last genetic variants together with four of the traditional risk factors (smoking, alcohol consumption, obesity and diabetes) are associated in a significant and independent way with essential hypertension. In a predictive model of hypertension, the introduction of genetic variants slightly increases the predictive value of the model.