Visible-Light-Responsive Photocatalytic Activity Significantly Enhanced by Active [VZn+VO+] Defects in Self-Assembled ZnO Nanoparticles.

Defect influences on the photoactivity of ZnO nanoparticles prepared by a powdered coconut water (ACP) assisted synthesis have been studied. The crystalline phase and morphology of ZnO nanoparticles were effectively controlled by adjusting the calcination temperature (400-700 °C). An induced transition of hybrid Zn5(CO3)2(OH)6/ZnO nanoparticles to single-phase ZnO nanoparticles was obtained at 480 °C. The morphological analysis revealed a formation of ZnO nanoparticles with semispherical (∼6.5 nm)- and rod-like (∼96 nm) shapes when the calcination temperatures were 400 and 700 °C, respectively. Photoluminescence characterizations revealed several defects types in the samples with VZn and VO+ being in the self-assembly of semispherical- and rod-like ZnO nanoparticles. The photocatalytic activity of the ZnO nanoparticles was examined by assessing the degradation of methylene blue in an aqueous solution under low-intensity visible-light irradiation (∼3 W m-2). The results point toward the self-assembly of semispherical- and rod-like ZnO nanoparticles that had significantly better photocatalytic activity (∼31%) in comparison to that of spherical-agglomerated- or near-spherical-like species within 120 min of irradiation. The possible photocatalytic mechanism is discussed in detail, and the morphology-driven intrinsic [VZn+VO+] defects are proposed to be among the active sites of the ZnO nanoparticles enhancing the photocatalytic activity.

A Cancelable Iris- and Steganography-Based User Authentication System for the Internet of Things.

Remote user authentication for Internet of Things (IoT) devices is critical to IoT security, as it helps prevent unauthorized access to IoT networks. Biometrics is an appealing authentication technique due to its advantages over traditional password-based authentication. However, the protection of biometric data itself is also important, as original biometric data cannot be replaced or reissued if compromised. In this paper, we propose a cancelable iris- and steganography-based user authentication system to provide user authentication and secure the original iris data. Most of the existing cancelable iris biometric systems need a user-specific key to guide feature transformation, e.g., permutation or random projection, which is also known as key-dependent transformation. One issue associated with key-dependent transformations is that if the user-specific key is compromised, some useful information can be leaked and exploited by adversaries to restore the original iris feature data. To mitigate this risk, the proposed scheme enhances system security by integrating an effective information-hiding technique-steganography. By concealing the user-specific key, the threat of key exposure-related attacks, e.g., attacks via record multiplicity, can be defused, thus heightening the overall system security and complementing the protection offered by cancelable biometric techniques.

Exploring the Interplay between Tribocorrosion and Surface Chemistry of the ASTM F139 Surgical Stainless Steel in Phosphate-Buffered Saline Solution.

Surgical ASTM F139 stainless steel is used for temporary fixtures in the biomedical field. Tribocorrosion is a major concern in this application. The aim of the present work was to study the interplay between tribocorrosion behavior and the surface chemistry of the ASTM F139 stainless steel in phosphate-buffered saline solution (PBS). Sliding wear tests were conducted against alumina balls at different electrochemical potentials: open circuit potential (OCP), cathodic potential (-100 mV versus the OCP), and anodic potentials (+200 mVAg/AgCl and +700 mVAg/AgCl). The normal load was 20 N. The wear volume was estimated based on micrographs obtained from the wear tracks using confocal laser scanning microscopy. Moreover, the wear tracks were also examined by scanning electron microscopy (SEM). The surface chemistry of the ASTM F139 specimens was analyzed by X-ray photoelectron spectroscopy (XPS). The wear volume was dependent on the electrochemical potential, being maximized at +700 mVAg/AgCl. Delamination areas and grooves were observed in the wear tracks. Detailed assessment of the surface chemistry inside the wear tracks allowed identification of the main chemical species and their relative quantities, thus enabling correlation of the passive film composition with the observed tribocorrosion behavior.

The influence of topical anesthetic and fluorescein on non-contact tonometry measurements using ultra-high-speed dynamic Scheimpflug.

This study aimed to investigate the effects of topical anesthetic and fluorescein drops on intraocular pressure (IOP), central corneal thickness (CCT) and biomechanical properties as measured by Corvis ST (CST-Oculus; Wezlar, Germany) in healthy eyes. A cross-sectional observational study was conducted on 46 healthy patients. The CST measurements were obtained before and immediately after the instillation of topical anesthetic and fluorescein drops. Pre-post instillation data were statistically analyzed. IOP measurements were compared to Goldmann's Applanation Tonometry (GAT), which was also performed after drops instillation. Biomechanical parameters analyzed included applanation 1 velocity, applanation 2 velocity, applanation 1 time, applanation 2 time, whole eye movement, deflection amplitude, and stiffness parameter at first applanation. A statistically significant difference in IOP, both for non-corrected IOP (IOPnct) and biomechanically corrected IOP (bIOP), was observed before and after the instillation of eyedrops. Despite this statistical significance, the observed difference lacked clinical relevance. The IOPnct demonstrated a significant difference pre and post-anesthetic and fluorescein instillation compared to GAT (14.99 ± 2.27 mmHg pre-instillation and 14.62 ± 2.50 mmHg post-instillation, versus 13.98 ± 2.04 mmHg, with p-values of 0.0014 and 0.0490, respectively). Comparable findings were noted when justaposing bIOP to GAT (14.53 ± 2.10 mmHg pre-instillation and 13.15 ± 2.25 mmHg post-instillation, against 13.98 ± 2.04 mmHg, with p-values of 0.0391 and 0.0022, respectively). Additionally, CCT measurements revealed a statistically significant elevation following the administration of topical anesthetic and fluorescein drops (from 544.64 ± 39.85 µm to 586.74 ± 41.71 µm, p < 0.01. None of the analyzed biomechanical parameters showed statistically significant differences after drops instillation. While the administration of topical anesthetic and fluorescein drops induced a statistically significant alteration in both IOPnct and bIOP readings, these changes were not clinically consequential. Furthermore, a notable statistical rise was observed in CCT measurements post-drops instillation, as determined by CST. Yet, corneal biomechanical parameters remained unaffected.

Insights into the Fe3+ Doping Effects on the Structure and Electron Distribution of Cr2O3 Nanoparticles.

Herein, we carefully investigated the Fe3+ doping effects on the structure and electron distribution of Cr2O3 nanoparticles using X-ray diffraction analysis (XRD), maximum entropy method (MEM), and density functional theory (DFT) calculations. We showed that increasing the Fe doping induces an enlargement in the axial ratio of c/a, which is associated with an anisotropic expansion of the unit cell. We found that as Fe3+ replaces Cr in the Cr2O3 lattice, it caused a higher interaction between the metal 3d states and the oxygen 2p states, which led to a slight increase in the Cr/Fe-O1 bond length followed by an opposite effect for the Cr/Fe-O2 bonds. Our results also suggest that the excitations characterize a well-localized bandgap region from occupied Cr d to unoccupied Fe d states. The Cr2O3 and Fe-doped Cr2O3 nanoparticles behave as Mott-Hubbard insulators due to their band gap being in the d-d gap, and Cr 3d orbitals dominate the conduction band. These findings suggest that the magnitude and the character of the electronic density near the O atom bonds in Cr2O3 nanoparticles are modulated by the Cr-Cr distances until its stabilization at the induced quasi-equilibrium of the Cr2O3 lattice when the Fe3+ doping values reaches the saturation level range.

Antiferromagnet-Ferromagnet Transition in Fe1-xCuxNbO4.

Iron niobates, pure and substituted with copper (Fe1-xCuxNbO4 with x = 0-0.15), were prepared by the solid-state method and characterized by X-ray diffraction, Raman spectroscopy, and magnetic measurements. The results of the structural characterizations revealed the high solubility of Cu ions in the structure and better structural stability compared to the pure sample. The analysis of the magnetic properties showed that the antiferromagnetic-ferromagnetic transition was caused by the insertion of Cu2+ ions into the FeNbO4 structure. The pure FeNbO4 structure presented an antiferromagnetic ordering state, with a Néel temperature of approximately 36.81K. The increase in substitution promoted a change in the magnetic ordering, with the state passing to a weak ferromagnetic order with a transition temperature (Tc) higher than the ambient temperature. The origin of the ferromagnetic ordering could be attributed to the increase in super-exchange interactions between Fe/Cu ions in the Cu2+-O-Fe3+ chains and the formation of bound magnetic polarons in the oxygen vacancies.

Evaluation of the Photocatalytic Activity of Distinctive-Shaped ZnO Nanocrystals Synthesized Using Latex of Different Plants Native to the Amazon Rainforest.

ZnO nanocrystals with three different morphologies have been synthesized via a simple sol-gel-based method using Brosimum parinarioides (bitter Amapá) and Parahancornia amapa (sweet Amapá) latex as chelating agents. X-ray diffraction (XRD) and electron diffraction patterns (SAED) patterns showed the ZnO nanocrystals were a pure hexagonal wurtzite phase of ZnO. XRD-based spherical harmonics predictions and HRTEM images depicted that the nanocrystallites constitute pitanga-like (~15.8 nm), teetotum-like (~16.8 nm), and cambuci-like (~22.2 nm) shapes for the samples synthesized using bitter Amapá, sweet Amapá, and bitter/sweet Amapá chelating agent, respectively. The band gap luminescence was observed at ~2.67-2.79 eV along with several structural defect-related, blue emissions at 468-474 nm (VO, VZn, Zni), green emissions positioned at 513.89-515.89 (h-VO+), and orange emission at 600.78 nm (VO+-VO++). The best MB dye removal efficiency (85%) was mainly ascribed to the unique shape and oxygen vacancy defects found in the teetotum-like ZnO nanocrystals. Thus, the bitter Amapá and sweet Amapá latex are effective chelating agents for synthesizing distinctive-shaped ZnO nanocrystals with highly defective and remarkable photocatalytic activity.

Corneal biomechanics and glaucoma beyond the bidirectional impact of intraocular pressure and corneal deformation response / Biomecânica corneana e glaucoma além do impacto bididirecional da pressão intraocular e da resposta da deformação corneana

ABSTRACT The purpose of this study was to highlight the impact of biomechanical corneal response in available in vivo tonometry methods for glaucoma management. Systematic review of non-contact air-puff tonometers that analyzes the corneal deformation response, with special focus on the investigation of the correlation of derived parameters with intraocular pressure measurements. The two actual and commercially available in vivo corneal tonometers provide promising information about biomechanical characteristics of the cornea and its relation to glaucoma, allowing the development of new protocols to evaluate, diagnose, and manage this disease.

RESUMO O objetivo deste estudo é destacar o impacto da resposta biomecânica corneana em métodos de tonometria in vivo disponíveis para o manejo do glaucoma. Trata-se de revisão sistemática de tonômetros de ar que analisa a resposta à deformação corneana, com foco especial na investigação da correlação dos parâmetros derivados com as medições da pressão intraocular. Os dois tonômetros mais recentes e comercialmente disponíveis fornecem informações promissoras sobre as características biomecânicas da córnea e sua relação com o glaucoma, permitindo o desenvolvimento de novos protocolos para avaliar, diagnosticar e controlar a doença.

Permanent Data Storage in ZnO Thin Films by Filamentary Resistive Switching.

Resistive memories are considered the most promising candidates for the next generation of non-volatile memory; however, attention has so far been limited to rewritable memory features for applications in resistive random access memories (RRAM). In this article, we provide a new insight into the applicability of resistive memories. The characteristics of non-rewritable resistive memories (NRRM) were investigated. Devices with Pt/ZnO/ITO architecture were prepared using magnetron sputtering, upon which various bipolar and unipolar resistive switching tests were performed. The results showed excellent distinction between the high resistance state (HRS) and low resistance state (LRS), with RHRS/RLRS = 5.2 × 1011 for the Pt/ZnO/ITO device with deposition time of 1 h. All samples were stable for more than 104 s, indicating that the devices have excellent applicability in NRRMs.

[Biventricular endomyocardiofibrosis associated with renal amyloidosis]. / Endomiocardiofibrose biventricular associada à amiloidose renal.

Endomyocardiofibrosis is a restrictive cardiomyopathy characterized by fibrotic involvement of the endocardium and adjacent myocardium, and by diastolic dysfunction caused by changes in distensibility making ventricular filling inadequate while preserving the systolic function. Clinically, it appears as heart failure, but etiological symptomatic discernment, suspicion and a clinical examination would be necessary in order to make a correct etiological diagnosis. The case of a patient with biventricular endomyocardial fibrosis associated with renal amyloidosis is presented.

Corrupção governamental e difusão do acesso à Internet: evidências globais / Corrupción gubernamental y difusión del acceso a Internet: evidencias globales / Government corruption and Internet access diffusion: global evidence

Resumo Este artigo investiga as relações entre difusão da internet, voz e accountability, dimensão cultural, corrupção e eficácia governamental, por meio de análise entre países realizada com 117 nações no período de 2000 a 2014. Adotando a técnica de Análise Robusta de Caminho para a análise de dados, conclui-se que, independentemente dos efeitos das variáveis de controle, a difusão da internet promove menores níveis de corrupção governamental, uma relação que ocorre direta e indiretamente via mediação de voz e accountability, que, por sua vez, apresenta forte correlação com a corrupção governamental. A título de contribuição teórica, reforça-se a compreensão de que a internet constitui uma importante ferramenta de combate à corrupção, além de evidenciar o papel moderador da dimensão cultural na relação entre voz e accountability e corrupção governamental e, sobretudo, de incorporar a eficácia governamental ao modelo teórico.

Resumen Este artículo investiga las relaciones entre difusión de Internet, voz, rendición de cuentas, dimensión cultural, corrupción y efectividad gubernamental mediante el análisis de 117 países, de 2000 a 2014. Usando el Robust Path Analysis como técnica de análisis de datos, se concluye que, independientemente de los efectos de las variables de control, la difusión de Internet promueve niveles más bajos de corrupción gubernamental, relación que ocurren directa e indirectamente a través de la mediación vocal y la rendición de cuentas, lo que a su vez presenta una fuerte correlación con la corrupción gubernamental. Como aportación teórica, se refuerza la idea de que Internet es una herramienta importante en la lucha contra la corrupción, además de evidenciar el papel moderador de la dimensión cultural en la relación entre la voz, la rendición de cuentas y la corrupción gubernamental y, sobre todo, incorporar la eficacia gubernamental al modelo teórico.

Abstract The relationship between Internet diffusion, voice and accountability, cultural dimension, corruption, and government effectiveness was investigated through a cross-country analysis of 117 countries from 2000 to 2014. Using Robust Path Analysis as a data analysis technique, it is concluded that, regardless of the effects of control variables, the diffusion of the Internet promotes lower levels of government corruption, occurring directly and indirectly through voice mediation and accountability, which, in turn, presents a strong direct relationship with government corruption. The focus on theoretical contribution reinforces the idea that the Internet is an important tool in the fight against corruption, as well as highlighting the role of cultural dimension, the relationship between voice and responsibility and government corruption, and, above all, incorporating government action into the theoretical model.

The ruler of inclusion in the process of people learning with visual disability.

The aim of this project is the development of a pedagogical tool that could address the needs related to the learning process of the blind and could also be used in the pedagogical process of people who are visually impaired. This project also has the objective of showing how the forms of the Ruler of Inclusion were planned in order to facilitate learning while addressing issues related to its safety, practicality and multifunctionality, aspects that are broached in a future work using descriptive, exploratory and phenomenological analyses to verify the understanding of the learning concepts applied to the ruler.

Divergent social functioning in behavioral variant frontotemporal dementia and Alzheimer disease: reciprocal networks and neuronal evolution.

Behavioral variant frontotemporal dementia (bvFTD) disrupts our most human social and emotional functions. Early in the disease, patients show focal anterior cingulate cortex (ACC) and orbital frontoinsula (FI) degeneration, accentuated in the right hemisphere. The ACC and FI, though sometimes considered ancient in phylogeny, feature a large bipolar projection neuron, the von Economo neuron (VEN), which is found only in humans, apes, and selected whales-all large-brained mammals with complex social structures. In contrast to bvFTD, Alzheimer disease (AD) often spares social functioning, and the ACC and FI, until late in its course, damaging instead a posterior hippocampal-cingulo-temporal-parietal network involved in episodic memory retrieval. These divergent patterns of functional and regional impairment remain mysterious despite extensive molecular-level characterization of bvFTD and AD. In this report, we further develop the hypothesis that VENs drive the regional vulnerability pattern seen in bvFTD, citing recent evidence from functional imaging in healthy humans, and also structural imaging and quantitative neuropathology data from bvFTD and AD. Our most recent findings suggest that bvFTD and AD target distinct, anticorrelated intrinsic connectivity networks and that bvFTD-related VEN injury occurs throughout the ACC-FI network. We suggest that the regional and neuronal vulnerability patterns seen in bvFTD and AD underlie the divergent impact of these disorders on recently evolved social-emotional functions.

Early frontotemporal dementia targets neurons unique to apes and humans.

OBJECTIVE: Frontotemporal dementia (FTD) is a neurodegenerative disease that erodes uniquely human aspects of social behavior and emotion. The illness features a characteristic pattern of early injury to anterior cingulate and frontoinsular cortex. These regions, though often considered ancient in phylogeny, are the exclusive homes to the von Economo neuron (VEN), a large bipolar projection neuron found only in great apes and humans. Despite progress toward understanding the genetic and molecular bases of FTD, no class of selectively vulnerable neurons has been identified. METHODS: Using unbiased stereology, we quantified anterior cingulate VENs and neighboring Layer 5 neurons in FTD (n = 7), Alzheimer's disease (n = 5), and age-matched nonneurological control subjects (n = 7). Neuronal morphology and immunohistochemical staining patterns provided further information about VEN susceptibility. RESULTS: FTD was associated with early, severe, and selective VEN losses, including a 74% reduction in VENs per section compared with control subjects. VEN dropout was not attributable to general neuronal loss and was seen across FTD pathological subtypes. Surviving VENs were often dysmorphic, with pathological tau protein accumulation in Pick's disease. In contrast, patients with Alzheimer's disease showed normal VEN counts and morphology despite extensive local neurofibrillary pathology. INTERPRETATION: VEN loss links FTD to its signature regional pattern. The findings suggest a new framework for understanding how evolution may have rendered the human brain vulnerable to specific forms of degenerative illness.

Análise do desenvolvimento de Arranjos Produtivos Locais (APLs): um estudo de caso do município de Paraty (RJ) / Development analysis of local productive arrangements (LPA): a study case of Paraty (RJ)

Este trabalho aborda o desenvolvimento local no município de Paraty, através da formação de APLs, especificamente neste caso voltados para a atividade turística. Através de informações obtidas por análise documental e entrevistas, pode-se analisar as potencialidades da região e apontar caminhos para incremento de sua competitividade, principalmente no que tange à integração e à formação de parcerias entre empresas, comunidade e poder público. Além disso, foram feitas sugestões para superar obstáculos, vencer desafios e aproveitar oportunidades, baseadas na vocação turística, para que a região se torne competitiva no mercado de destinos turísticos, fidelizando e ampliando a base de turistas, através do melhor aproveitamento de seus encantos naturais, históricos e culturais. Os principais resultados mostram que Paraty carece de melhorias de infraestrutura para desenvolver o turismo local, que vão desde o saneamento básico até o melhor treinamento e capacitação de mão de obra. Além disso, toda a estrutura existente ainda não pode ser considerada efetivamente um APL, apesar de já se observar uma organização da rede de pequenas e médias empresas voltada para o desenvolvimento turístico sustentável do município. O que se encontra, em termos de organização em rede, é um APL ainda informal, onde praticamente inexiste a liderança e a confiança interna.

This paper discusses the development in the municipality of Paraty, through the formation of LPAs, specifically in this case focused on tourism. By the information obtained through interviews and document analysis, we can analyze the region's potential and show ways to improve their competitiveness, especially regarding the integration and formation of partnerships between business, community and government. In addition, suggestions were made to overcome obstacles, overcome challenges and seize opportunities, based on tourist so that the region becomes competitive in the market of tourist destinations, customizing and expanding the base of tourists through the best use of their natural charms, history and culture. The main results show that Paraty lacks infrastructure improvements to develop local tourism, ranging from the basic sanitation to the best training and qualification of workforce. Moreover, the entire existing structure still can not be effectively considered an LPA, in spite of a network organization of small and medium enterprises focused on sustainable tourism development in the municipality. What becomes clear in terms of networking, is an informal LPA, where nonexistent leadership and inner confidence.

Ocupações de terra, acampamentos e demandas ao Estado: uma análise em perspectiva comparada / Occupations de terres, campements et demandes adressées à l'État: analyse de perspective comparée / Land occupations, landless camps, and demands on the State: an evaluation from a comparative perspective

Based on the observation that land occupations with camps currently place an unavoidable demand on the Brazilian state for land expropriation and redistribution, the article analyzes the sociogenesis of this discourse. The authors seek to: examine how the first landless camps emerged; understand how men and women mobilized to occupy land; and identify relations between the original landless camps in Brazil and the current ones. The article takes a comparative approach, focusing on the individuals involved in the first land occupations in the South, Southeast, and Northeast of the country. In the conclusion, the authors show how such discourse draws on individual initiatives and the intersection between historical processes, the constitution of movements, and the response by the Brazilian state.

À partir du constat que les occupations de terres suivies de campements constituent actuellement au Brésil un langage incontournable employé pour demander à l'État l'expropriation et la redistribution des terres, dans cet article on analyse la sociogenèse de ce langage. On cherche à examiner comment ont été mis en place les premiers campements, comment hommes et femmes se sont disposés à occuper des terres, et identifier les relations entre ces campements et ceux de nos jours. On se sert d'une approche comparative dont le fil conducteur est le groupe d’individus engagé dans les premières occupations au sud, sud-est et nord-est du Brésil. On voit que le langage est tributaire d'initiatives individuelles, du croisement de processus historiques, de la constitution de mouvements et de la façon d'écouter de l'État brésilien.

Endomiocardiofibrose biventricular associada à amiloidose renal / Biventricular endomyocardiofibrosis associated with renal amyloidosis

A endomiocardiofibrose (EMF) é uma cardiomiopatia restritiva, caracterizada por envolvimento fibrótico do endocárdio e miocárdio adjacente, e disfunção diastólica, causada por alteração da distensibilidade, dificultando o enchimento ventricular adequado, estando a função sistólica preservada. Clinicamente, apresenta-se como insuficiência cardíaca, mas, para o diagnóstico etiológico correto, são necessárias perspicácia semiológica, suspeita e investigação clínica. Relatamos o caso de uma paciente portadora de endomiocardiofibrose biventricular associada à amiloidose renal.

Chest pain due to right atrial compression caused by a thymolipoma

Timolipomas são tumores raros do mediastino constituídos de tecido gorduroso e tímico, que podem atingir grandes proporções e se manifestar clinicamente através de compressão a estruturas adjacentes. Seu comportamento é benigno e o tratamento é a excisão cirúrgica. Relatamos o caso de um jovem hígido que apresentava precordialgia e dispnéia como principais sintomas de um timolipoma de aproximadamente 12cm comprimindo o átrio direito.

Reflexões sobre a Federação brasileira / Reflections about the Brazilian Federation

Aborda a questão do pacto federativo e seus respectivos desdobramentos. Destaca as discussões relativas às desigualdades sócio-econômicas inter-regionais e a atual estrutura de distribuição de recursos entre as esferas de governo e seus impactos sobre os entes federados