Novel Sol-Gel Synthesis Route for Ce- and V-Doped Ba0.85Ca0.15Ti0.9Zr0.1O3 Piezoceramics.

To meet the current demand for lead-free piezoelectric ceramics, a novel sol-gel synthesis route is presented for the preparation of Ba0.85Ca0.15Ti0.9Zr0.1O3 doped with cerium (Ce = 0, 0.01, and 0.02 mol%) and vanadium (V = 0, 0.3, and 0.4 mol%). X-ray diffraction patterns reveal the formation of a perovskite phase (space group P4mm) for all samples after calcination at 800 °C and sintering at 1250, 1350, and 1450 °C, where it is proposed that both dopants occupy the B site. Sintering studies show that V doping allows the sintering temperature to be reduced to at least 1250 °C. Undoped BCZT samples sintered at the same temperature show reduced functional properties compared to V-doped samples, i.e., d33 values increase by an order of magnitude with doping. The dissipation factor tan δ decreases with increasing sintering temperature for all doping concentrations, while the Curie temperature TC increases for all V-doped samples, reaching 120 °C for high-concentration co-doped samples. All results indicate that vanadium doping can facilitate the processing of BCZT at lower sintering temperatures without compromising performance while promoting thermal property stability.

Investigation of the Chemical Composition, Microstructure, Density, Microhardness, and Elastic Modulus of the New ß Ti-50Nb-xMo Alloys for Biomedical Applications.

ß-type titanium alloys with a body-centered cubic structure are highly useful in orthopedics due to their low elastic modulus, lower than other commonly used alloys such as stainless steel and Co-Cr alloys. The formation of the ß phase in titanium alloys is achieved through ß-stabilizing elements such as Nb, Mo, and Ta. To produce new ß alloys with a low modulus of elasticity, this work aimed to produce our alloy system for biomedical applications (Ti-50Nb-Mo). The alloys were produced by arc-melting and have the following compositions Ti-50Nb-xMo (x = 0, 3, 5, 7, and 12 wt% Mo). The alloys were characterized by density, X-ray diffraction, scanning electron microscopy, microhardness, and elastic modulus. It is worth highlighting that this new set of alloys of the Ti-50Nb-Mo system produced in this study is unprecedented; due to this, there needs to be a report in the literature on the production and structural characterization, hardness, and elastic modulus analyses. The microstructure of the alloys has an exclusively ß phase (with bcc crystalline structure). The results show that adding molybdenum considerably increased the microhardness and decreased the elastic modulus, with values around 80 GPa, below the metallic materials used commercially for this type of application. From the produced alloys, Ti-50Nb-12Mo is highlighted due to its lower elastic modulus.

Insertion torque, flexural strength and surface alterations of stainless steel and titanium alloy orthodontic mini-implants: an in vitro study

ABSTRACT Objective: This study aimed to compare the insertion torque (IT), flexural strength (FS) and surface alterations between stainless steel (SS-MIs) and titanium alloy (Ti-MIs) orthodontic mini-implants. Methods: Twenty-four MIs (2 x 10 mm; SS-MIs, n = 12; Ti-MIs, n = 12) were inserted on artificial bone blocks of 20 lb/ft3 (20 PCF) and 40 lb/ft3 (40 PCF) density. The maximum IT was recorded using a digital torque meter. FS was evaluated at 2, 3 and 4 mm-deflection. Surface topography and chemical composition of MIs were assessed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). General linear and mixed models were used to assess the effect of the MI type, bone density and deflection on the evaluated outcomes. Results: The IT of Ti-MIs was 1.1 Ncm greater than that obtained for the SS-MIs (p= 0.018). The IT for MIs inserted in 40 PCF test blocks was 5.4 Ncm greater than that for those inserted in 20 PCF test blocks (p < 0.001). SS-MIs inserted in higher density bone (40 PCF) had significantly higher flexural strength than the other groups, at 2 mm (98.7 ± 5.1 Ncm), 3 mm (112.0 ± 3.9 Ncm) and 4 mm (120.0 ± 3.4 Ncm) of deflection (p< 0.001). SEM evidenced fractures in the Ti-MIs. EDS revealed incorporation of 18% of C and 2.06% of O in the loaded SS-MIs, and 3.91% of C in the loaded Ti-MIs. Conclusions: Based on the findings of this in vitro study, it seems that SS-MIs offer sufficient stability and exhibit greater mechanical strength, compared to Ti-MIs when inserted into higher density bone.

RESUMO Objetivo: O objetivo deste estudo foi comparar o torque de inserção (TI), a resistência flexural (RF) e as alterações de superfície em mini-implantes ortodônticos de aço inoxidável (MIs-Ai) e de liga de titânio (MIs-Ti). Métodos: Vinte e quatro MIs (2 x 10 mm; MIs-Ai, n = 12; MIs-Ti, n = 12) foram inseridos em blocos de osso artificial de densidades de 20 lb/ft3 (20 PCF) e 40 lb/ft3 (40 PCF). O torque máximo de inserção foi registrado por meio de um torquímetro digital. A resistência flexural foi avaliada nas deflexões de 2, 3 e 4 mm. Topografia de superfície e composição química dos MIs foram avaliadas por Microscopia Eletrônica de Varredura (MEV) e Espectroscopia de Energia Dispersiva de Raios X (EDS). Modelos lineares gerais e mistos foram utilizados para avaliar o efeito do tipo de MI, da densidade óssea e da deflexão nos desfechos avaliados. Resultados: O TI dos MIs-Ti foi 1,1 Ncm maior do que o obtido para os MIs-Ai (P = 0,018). O TI para MIs inseridos em blocos de teste de 40 PCF foi 5,4 Ncm maior do que para aqueles inseridos em blocos de teste 20 PCF (p < 0,001). MIs-Ai inseridos em osso de maior densidade (40 PCF) apresentaram resistência flexural significativamente maior do que outros grupos, em deflexões de 2 mm (98,7 ± 5,1 Ncm), 3 mm (112,0 ± 3,9 Ncm) e 4 mm (120,0 ± 3,4 Ncm) (p < 0,001). A MEV evidenciou fraturas nos MIs-Ti. A EDS revelou incorporação de 18% de C e 2,06% de O nos MIs-Ai e 3,91% de C nos MIs-Ti, ambos submetidos a testes mecânicos. Conclusões: Com base nos resultados desse estudo in vitro, os MIs-Ai aparentam oferecer adequada estabilidade e maior resistência mecânica, em comparação aos MIs-Ti, quando inseridos em osso de maior densidade.

Simulation of the Influence of the Radial Graded Porosity Distribution on Elastic Modulus of γ/ß Phase Ti-Based Alloy Foams for Bone Implant.

This research aims to examine how a radial graded porosity distribution affects the elastic modulus by conducting simulations on Ti-based alloy foams with face-centered cubic and body-centered cubic crystal structures. Four types of foams were analyzed; commercially pure-Ti, Ti-13Ta-6Mn (TTM), Ti-13Ta-(TT) and Ti-13Ta-6Sn (TTS), (all in at.%). Four radial graded porosity distribution configurations were modeled and simulated using the finite element analysis (FEA). The radial graded porosity distribution configurations were generated using a Material Designer (Ansys) with a pore range of 200 to 600 µm. These radial graded porosity distributions had average porosity values of 0, 20, 30 and 40%. The consolidated samples that were obtained through a powder metallurgy technique in two step samples were synthesized using a powder metallurgy technique, with the elastic moduli values of the aforementioned Ti based alloys being measured by ultrasound using ~110, ~69, ~61 and ~65 GPa, respectively. The results showed that the modulus decreased as a function of porosity level in all simulated materials. The TTM, TT and TTS foams, with average porosities of 20, 30 and 40%, exhibited an modulus smaller than 30 GPa, which is a requirement to be used as a biomaterial in human bones. The TT foams showed the lowest modulus when compared to the other foams. Finally, certain theoretical models were used to obtain the modulus, the best being; the Gibson-Ashby model (α = 1 and n = 2.5) for the cp-Ti foams and Knudsen-Spriggs model (b = 3.06) for the TTM, TT and TTS foams.

Violencia psicológica en el noviazgo: análisis de las redes semánticas de estudiantes universitarios argentinos / Psychological Violence during Courtship: Analysis of the Semantic Networks of Argentine University Students

Resumen En la actualidad, la violencia psicológica (VP) en las relaciones de noviazgo es un fenómeno prevalente. El objetivo de este estudio fue analizar y comprender las redes de significados acerca de la VP en el noviazgo según los estudiantes de la Facultad de Psicología de la Universidad del Aconcagua a través del software ATLAS.ti. Es una investigación cualitativa, estudio descriptivo, con un diseño fenomenológico en una muestra intencional de estudiantes universitarios argentinos. Participaron un total de 153 estudiantes de 1º y 4º año, de ambos sexos, con una edad promedio de 22 años (rango de 18 a 25) que hubieran mantenido alguna relación de noviazgo. La técnica utilizada fue el grupo focal y se usó el software ATLAS.ti para el análisis de los datos. Se obtuvieron cuatro líneas temáticas: Diferencias entre VP y violencia física, Emociones de la VP en el noviazgo, Conductas en la VP en el noviazgo y Consecuencias en futuras relaciones. Se concluye que la VP es considerada como más dañina, que pasa desapercibida y se naturaliza. Angustia, culpa y miedo son algunas de las emociones que provoca la VP, y la manipulación, el maltrato y el control algunas de las conductas que manifiestan VP en el noviazgo. Como consecuencias en futuras relaciones, destacan el miedo y el establecimiento de nuevas relaciones de pareja similares. Urge diseñar programas de prevención temprana para minimizar el impacto de sus consecuencias, fomentando el amor y el respeto en las relaciones entre jóvenes.

Abstract Introduction: Psychological violence (PSV) in dating relationships is currently prevalent. Objective: Analyze and understand the networks of meanings of PSV in the dating of students from the Faculty of Psychology of the University of Aconcagua by means of the ATLAS.ti software. Method: Qualitative research, descriptive study, with a phenomenological design in an intentional sample of university students from Argentina. A total of 153 students from 1st and 4th year, of both sexes, with an average age of 22 years (range of 18 to 25) who would have had some relationship. The instrument used was the focus group and the ATLAS.ti software was used to analyze the data. Results: Four thematic lines were obtained: Differences between PSV and physical violence, Emotions of PSV in courtship, PSV behaviors in in courtship and Consequences in future relationships. Conclusions: PSV was considered more harmful, unnoticed, and naturalized. Distress, guilt, and fear are some of the emotions that PSV provokes; and manipulation, abuse, and control are some of its behaviors. As consequences in future relationships the fear of the establishing new relationships with a similar partner stands out. There is an urgent need to design early prevention programs to minimize the impact of their consequences, fostering love and respect in relationships between young people.

Age-related variation in malignant cytology rates of thyroid nodules: insights from a retrospective observational study assessing the ACR TI-RADS.

OBJECTIVE: The influence of age on the malignant cytology rate of thyroid nodules remains uncertain. The American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) is currently used to guide subsequent investigations of thyroid nodules, regardless of clinical variables. This study aimed to investigate the impact of age on the malignant cytology rates of thyroid nodules and the diagnostic performance of ACR TI-RADS across different age groups. DESIGN: A retrospective, single-center, observational study. METHODS: Patients aged ≥ 20 years with thyroid nodules, who underwent fine-needle aspiration biopsy between 2012 and 2019 were evaluated. Ultrasound images were used to obtain the TI-RADS data. Malignancy was determined based on suspicious for malignancy (Bethesda V) and malignant (Bethesda VI) cytology results or malignancy in cell block analysis. RESULTS: A total of 1023 nodules from 921 patients (88.2% female) were analyzed. The median age was 58.5 (interquartile range [IQR], 41.1-66.6) years, and the median nodule size was 2.4 (IQR, 1.7-3.6) cm. Stratification by age revealed a decreasing prevalence of malignant cytology across subgroups of 20-39, 40-59, and ≥60 years (10.7%, 8.5%, and 3.7%, respectively; P = .002). After adjusting for sex, multinodularity, nodule size, and ACR TI-RADS category, we observed that each year of age reduced the OR for malignant cytology by 3.0% (95% CI: 0.7%-5.3%; P = .011). When comparing the subgroups of 20-39 and ≥60 years, the malignant cytology rate decreased by half in TI-RADS 4 (from 21.4% to 10.4%) and two-thirds in TI-RADS 5 (from 64.7% to 22.6%). CONCLUSIONS: Our study demonstrated that as patient age increased, the rate of malignant cytology in thyroid nodules decreased. Moreover, age significantly influences the malignancy rates of thyroid nodules classified according to the ACR TI-RADS.

A photochemical route in the synthesis and characterization of La2Ti2O7 and La2Ti2O7/AgO films and its evaluation in Congo red degradation and as antibacterial control to Staphylococcus aureus.

In this article, we propose a simple photochemical method to synthesize pure La2Ti2O7 films and La2Ti2O7 films doped with silver at 1.0, 3.0, and 5.0 mol%. After annealing the photo-deposited films at 900 °C, XRD, SEM, and XPS analyses showed the formation of a monoclinic La2Ti2O7 phase and the presence of Ag and AgO in doped samples. Photocatalytic tests for Congo red degradation demonstrated that pure La2Ti2O7 achieved 25.4% degradation, while doped samples reached a maximum of 92.7% degradation. Moreover, increasing silver doping on La2Ti2O7 films significantly reduced the growth of Staphylococcus aureus, indicating potential antibacterial properties. The enhanced photoactivity was attributed to the formation of a type I heterojunction between La2Ti2O7 and AgO, and a degradation mechanism was proposed based on Congo red degradation.

Morphological analysis of plasma electrolytic oxidation coatings formed on Ti6Al4V alloys manufactured by electron beam powder bed fusion.

This study investigates and compares plasma electrolytic oxidation (PEO) coatings produced on wrought Ti6Al4V alloy substrates with those resulting from electron beam powder bed fusion (PBF-EB). For a duration of 1000 s, a phosphate/silicate electrolyte with a current density of 50 A/cm2 was employed to fabricate the coatings. Surface and polished cross-sections of the coated specimens underwent SEM and X-ray diffraction (XRD) analyses. The obtained coatings exhibit differences of up to approximately 18% in thickness and formation, as well as in their anatase phase. The anatase phase is present at a level of 54.09% in the substrates processed by PBF-EB and 38.54% in wrought substrates. After 1000 s of PEO, the coatings formed on the wrought substrates exhibited higher porosity and larger pores (>1 µm) compared to those produced on the PBF-EB specimens. The PBF-EB coatings had lower porosity because they contained fewer pores larger than 1 µm. The findings imply that the unique microstructural arrangement of PBF-EB-produced additively made Ti6Al4V materials plays a significant impact in the development and morphological properties of PEO oxide coatings.

Assessing the electrochemical degradation of reactive orange 84 with Ti/IrO2-SnO2-Sb2O5 anode using electrochemical oxidation, electro-Fenton, and photoelectro-Fenton under UVA irradiation.

Today, water shortage problems around the world have forced the search for new treatment alternatives, in this context, electrochemical oxidation technology is a hopeful process for wastewater treatment, although it is still needed exploration of new efficient and economically viable electrode materials. In this way, mixed metal oxide anodes look like promising alternatives but their preparation is still a significant point to study, searching for finding low-cost materials to improve electrocatalytic efficiencies. In an exploration of this kind of highly efficient materials, this work presents the results obtained using an MMO Ti/IrO2-SnO2-Sb2O5 anode. All the prepared anodes exhibited excellent physical and electrochemical properties. The electrochemical oxidation of 100 mL and 200 mg L-1 Reactive Orange 84 (RO 84) diazo dye was studied using 3 cm2 of such synthesized anodes by applying current densities of 25, 50, and 100 mA cm-2. Faster and more efficient electrochemical oxidation occurred at 100 mA cm-2 with 50 mM of Na2SO4 + 10 mM NaCl as supporting electrolyte at pH 3.0. The degradation and mineralization processes of the above solution were enhanced with the electro-Fenton process with 0.05 mM Fe2+ and upgraded using photoelectron-Fenton with UVA light. This process yielded 91% COD decay with a low energy consumption of 0.1137 kWh (g COD)-1 at 60 min. The evolution of a final carboxylic acid like oxalic was followed by HPLC analysis. The Ti/IrO2-SnO2-Sb2O5 is then an efficient and low-cost anode for the photoelectro-Fenton treatment of RO 84 in a chloride and sulfate media.

Computational Study of the Influence of α/ß-Phase Ratio and Porosity on the Elastic Modulus of Ti-Based Alloy Foams.

This work aims to perform a computational analysis on the influence that microstructure and porosity have on the elastic modulus of Ti-6Al-4V foams used in biomedical applications with different α/ß-phase ratios. The work is divided into two analyses, first the influence that the α/ß-phase ratio has and second the effects that porosity and α/ß-phase ratio have on the elastic modulus. Two microstructures were analyzed: equiaxial α-phase grains + intergranular ß-phase (microstructure A) and equiaxial ß-phase grains + intergranular α-phase (microstructure B). The α/ß-phase ratio was variated from 10 to 90% and the porosity from 29 to 56%. The simulations of the elastic modulus were carried out using finite element analysis (FEA) using ANSYS software v19.3. The results were compared with experimental data reported by our group and those found in the literature. The ß-phase amount and porosity have a synergic effect on the elastic modulus, for example, when the foam has a porosity of 29 with 0% ß-phase, and it has an elastic modulus of ≈55 GPa, but when the ß-phase amount increases to 91%, the elastic modulus decreases as low as 38 GPa. The foams with 54% porosity have values smaller than 30 GPa for all the ß-phase amounts.

Laser-Modified Ti Surface Improves Paracrine Osteogenesis by Modulating the Expression of DKK1 in Osteoblasts.

Titanium surface modifications are widely used to modulate cellular behavior by recognition of topographical cues. However, how those modifications affect the expression of mediators that will influence neighboring cells is still elusive. This study aimed to evaluate the effects of conditioned media from osteoblasts cultured on laser-modified titanium surfaces on the differentiation of bone marrow cells in a paracrine manner and to analyze the expression of Wnt pathway inhibitors. Mice calvarial osteoblasts were seeded on polished (P) and Yb:YAG laser-irradiated (L) Ti surfaces. Osteoblast culture media were collected and filtered on alternate days to stimulate mice BMCs. Resazurin assay was performed every other day for 20 days to check BMC viability and proliferation. After 7 and 14 days of BMCs maintained with osteoblasts P and L-conditioned media, alkaline phosphatase activity, Alizarin Red staining, and RT-qPCR were performed. ELISA of conditioned media was conducted to investigate the expression of Wnt inhibitors Dickkopf-1 (DKK1) and Sclerostin (SOST). BMCs showed increased mineralized nodule formation and alkaline phosphatase activity. The L-conditioned media enhanced the BMC mRNA expression of bone-related markers Bglap, Alpl, and Sp7. L-conditioned media decreased the expression of DKK1 compared with P-conditioned media. The contact of osteoblasts with Yb:YAG laser-modified Ti surfaces induces the regulation of the expression of mediators that affect the osteoblastic differentiation of neighboring cells. DKK1 is among these regulated mediators.

Titanium-doped PET nanoplastics of environmental origin as a true-to-life model of nanoplastic.

The increased presence of secondary micro/nanoplastics (MNPLs) in the environment requires urgent studies on their potentially hazardous effects on exposed organisms, including humans. In this context, it is essential to obtain representative MNPL samples for such purposes. In our study, we have obtained true-to-life NPLs resulting from the degradation, via sanding, of opaque PET bottles. Since these bottles contain titanium (TiO2NPs), the resulting MNPLs also contain embedded metal. The obtained PET(Ti)NPLs were extensively characterized from a physicochemical point of view, confirming their nanosized range and their hybrid composition. This is the first time these types of NPLs are obtained and characterized. The preliminary hazard studies show their easy internalization in different cell lines, without apparent general toxicity. The demonstration by confocal microscopy that the obtained NPLs contain Ti samples offers this material multiple advantages. Thus, they can be used in in vivo approaches to determine the fate of NPLs after exposure, escaping from the existing difficulties to follow up MNPLs in biological samples.

Exploring the functionalization of Ti-6Al-4V alloy with the novel antimicrobial peptide JIChis-2 via plasma polymerization.

This study aimed to characterize the immobilization of the novel JIChis-2 peptide on the Ti-6Al-4V alloy, widely used in the biomedical sector. The antimicrobial activity of JIChis-2 was evaluated in the Gram-negative bacterium E. coli. Its immobilization occurred by inducing the formation of covalent bonds between the N-terminus of the peptides and the surface previously submitted to acrylic acid polymerization via the PECVD technique. Coated and uncoated surfaces were characterized by FTIR, AFM, SEM and EDX. Studies of global and localized corrosion were carried out, seeking to explore the effects triggered by surface treatment in an aggressive environment. Additionally, the ability of the functionalized material to prevent E. coli biofilm formation evidenced that the strategy to immobilize JIChis-2 in the Ti-6Al-4V alloy via PECVD of acrylic acid resulted in the development of a functional material with antibiofilm properties.

Mechanical Properties, Corrosion Behavior, and In Vitro Cell Studies of the New Ti-25Ta-25Nb-5Sn Alloy.

This study aims to characterize a new Ti-25Ta-25Nb-5Sn alloy for biomedical application. Microstructure, phase formation, mechanical and corrosion properties, along with the cell culture study of the Ti-25Ta-25Nb alloy with Sn content 5 mass% are presented in this article. The experimental alloy was processed in an arc melting furnace, cold worked, and heat treated. For characterization, optical microscopy, X-ray diffraction, microhardness, and Young's modulus measurements were employed. Corrosion behavior was also evaluated using open-circuit potential (OCP) and potentiodynamic polarization. In vitro studies with human ADSCs were performed to investigate cell viability, adhesion, proliferation, and differentiation. Comparison among the mechanical properties observed in other metal alloy systems, including CP Ti, Ti-25Ta-25Nb, and Ti-25Ta-25-Nb-3Sn showed an increase in microhardness and a decrease in the Young's modulus when compared to CP Ti. The potentiodynamic polarization tests indicated that the corrosion resistance of the Ti-25Ta-25Nb-5Sn alloy was similar to CP Ti and the experiments in vitro demonstrated great interactions between the alloy surface and cells in terms of adhesion, proliferation, and differentiation. Therefore, this alloy presents potential for biomedical applications with properties required for good performance.

Hydrogen physisorption on the (BeO)n, B2H4(Be,Ti), and B6Ti3 metal clusters: a computational study of energies and atomic charges.

The equilibrium structures of BeO clusters and Be,Ti-decorated boranes were computed with the ωB97X-D method and the 6-31G + (2d,2p) and aug-cc-pVTZ basis sets to study their intermolecular interactions with hydrogen molecules. Thermochemical and molecular properties such as the harmonic vibrational frequency, dipole and quadrupole moments, and atomic charges are employed to understand the attractive interactions that control the adsorption process. Comparison of molecular properties and atomic charges of the studied compounds before and after H2 molecule adsorption shows that most of the interactions among the BeO clusters and boranes with H2 molecules constitute a combination of dispersion, electrostatic, and weak charge transfer interactions. Calculated values of Hirschfeld atomic charges and ΔEe (in parenthesis) (BeO)4.8H2 (0.028 e and -2.0 kcal.mol-1), (BeO)2.12H2 (0.030 e and -2.8 kcal.mol-1), B6Ti3.10H2 (0.045 e and -15.4 kcal.mol-1), and B6Ti3+.10H2 (0.058 e and -15.3 kcal.mol-1) show qualitative correlation between hydrogen atomic charges and electronic energy of hydrogen interaction. The ωB97X-D/6-31 + G(2d,2p) values of Gibbs free energy at 298.15 K for (BeO)4.8H2 B2H4Ti.4H2 and B6Ti3.10H2 clusters are equal to -5.0, -4.9, and -5.1 kcal.mol-1, respectively, which are within the range of energy parameters of materials that could be employed in hydrogen storage tanks for light vehicles.

Black TiO2 Photoanodes for Direct Methanol Photo Fuel Cells.

Photocatalytic fuel cells (PFCs) are considered the next generation of energy converter devices, since they can harvest solar energy through relatively low-cost semiconductor material to convert the chemical energy of renewable fuels and oxidants directly into electricity. Here, we report black TiO2 nanoparticle (NP) photoanodes for simple single-compartment PFCs and microfluidic photo fuel cells (µPFCs) fed by methanol. We show that Ti3+ and oxygen vacancy (OV) defects at the TiO2 NPs are easily controlled by annealing in a NaBH4-containing atmosphere. This optimized noble-metal-free black TiO2 photoanode shows superior PFC performance for methanol oxidation and O2 reduction with a maximum power density (Pmax) ∼2000% higher compared to the undoped TiO2. At flow conditions, the black TiO2 photoanode showed a Pmax ∼90 times higher than the µFC equipped with regular TiO2 in the dark. The PFC and µPFC operate spontaneously with little activation polarization, and black TiO2 photoanodes are stable under light irradiation. The improved photoactivity of the black TiO2 photoanode is a consequence of the self-doping with Ti3+/OV defects, which significantly red-shifted the bandgap energy, induced intragap electronic states, and widened both the valence band and conduction band, enhancing the overall absorption of visible light and decreasing the interfacial charge transfer resistance.

Precisión de la PAAF en el reporte histopatológico de cirugía de tiroides

Objetivo: evaluar la precisión de los distintos puntos de corte del score Bethesda de la BAAF, en comparación con el estudio histopatológico para el diagnóstico de patología tiroidea. Métodos: estudio cuantitativo, observacional, de tipo transversal, analítico para la evaluación de pruebas diagnósticas. Incluyó 293 pacientes con patología tiroidea sugestiva de cáncer, que acudieron a Servicio de Cirugía General del Hospital Obrero N° 2 de la Caja Nacional de Salud, durante el periodo de 2019-2022. Se realizó un muestreo no aleatorizado por conveniencia que incluía a todos los pacientes disponibles. Resultados: se afirma la correlación entre las dos variables estudiadas, es decir, entre el puntaje del score Bethesda y el reporte del estudio histopatológico, con un intervalo de confianza (IC) del 95%. Conclusiones: se demuestra que la BAAF tiene alta especificidad en el diagnóstico de cancer de tiroides con reporte Bethesda V y VI, por el contrario, reportes Bethesda menores II, III y IV, descartan el diagnóstico.

Objective: to evaluate the precision of the different cut-off points of the BAAF Bethesda score in comparison with the histopathological study for the diagnosis of thyroid pathology. Methods: quantitative, observational, cross-sectional, analytical study for the evaluation of diagnostic tests. It included 293 patients with thyroid disease suggestive of cancer, who attended the General Surgery Service of Hospital Obrero No. 2 of the National Health Fund, during the period 2019-2022. Non-randomized convenience sampling was performed that included all available patients. Results: the correlation between the two variables studied was confirmed, that is, between the Bethesda score and the histopathological study report, with a confidence interval (CI) of 95%. Conclusions: it is demonstrated that the BAAF has high specificity in the diagnosis of thyroid cancer with Bethesda reports V and VI, on the contrary, minor Bethesda reports II, III, and IV, rule out the diagnosis.

Correlación ultrasonográfica entre volumen tiroideo y ti-rads. Estudio prospectivo / Ultrasonographic correlation between thyroid volume and ti-rads. Prospective study

La comunidad científica se ha preocupado por cuantificar el volumen tiroideo según variables como sexo, edad y deficiencias de yodo asociadas, sin embargo, pese al uso globalizado de TI-RADS para estimación de riesgo de malignidad en la patología tiroidea, no existe suficiente información en relación a si el tamaño de la glándula guarda o no relación con esta escala. Objetivo: comparar el Volumen Tiroideo con TI-RADS en pacientes atendidos en la unidad de ecografía diagnóstica del Centro Clínico Naguanagua en el período enero 2022 - enero 2023. Métodos: estudio observacional-descriptivo de nivel comparativo, con diseño transversal y prospectivo. Muestra no probabilística censal, abarcando la totalidad de los pacientes a los cuales se les efectuó ecografía tiroidea en el período establecido. Se efectuó un registro en cuanto a la cuantificación del volumen de: lóbulo tiroideo derecho, lóbulo tiroideo izquierdo y total de tiroides, TI-RADS, edad y sexo del paciente. Se utilizó el estadístico ANOVA y se empleó el programa Statistical® de licencia libre. Resultados: muestra de 126 pacientes, con edad promedio de 51,71 años ± 1,44, mediana de 53 años. Cuando se comparó el Volumen Total de Tiroides con TI-RADS, se constató que el mayor promedio lo registraron aquellos pacientes clasificados como 4B (p <0,05). Conclusión: aun cuando se registran mayores promedios de volumen total glandular en pacientes con hallazgos nodulares, llama la atención que entre los datos registrados existan pacientes con valores muy similares a lo reportado en la literatura como volúmenes normales en presencia de patología nodular tiroidea(AU)

The scientific community has been concerned with quantifying thyroid volume according to variables such as sex, age, and associated iodine deficiencies; however, despite the global use of TI-RADS to estimate the risk of malignancy in thyroid pathologies, there is not enough information in regarding whether or not the size of the gland is related to this scale. Objective: to compare the Thyroid Volume with TI-RADS in patients treated in the diagnostic ultrasound unit of the Naguanagua Clinical Center in the period January 2022 - January 2023. Methods: observational-descriptive study of a comparative level, with a crosssectional and prospective design. Non-probabilistic census sample, covering all the patients who underwent thyroid ultrasound in the established period. A record was made regarding the quantification of the volume of: right thyroid lobe, left thyroid lobe and total thyroid, TI-RADS, age and sex of the patient. The ANOVA statistic was used and the free license Statistical® program was used. Results: sample of 126 patients, mean age 51.71 ± 1.44 years, median 53 years. When the Total Thyroid Volume was compared with TI-RADS, it was found that the highest mean was registered by those patients classified as 4B (p <0.05). Conclusion: even when higher total glandular volume averages are recorded in patients with nodular findings, it is noteworthy that among the recorded data there are patients with values very similar to those reported in the literature as normal volumes in the presence of thyroid nodular pathology(AU)

The role of IT capabilities, IT reconfiguration capability and innovativeness on organizational performance: evidence from the Brazilian public sector / Papel de las capacidades de TI, capacidad de reconfiguración de TI e innovación en el desempeño organizacional: evidencia del sector público brasileño / O papel das capacidades de TI, capacidade de reconfiguração de TI e inovatividade no desempenho organizacional: evidências do setor público brasileiro

Abstract The growing investments in information technology (IT) each year pushes public sector organizations to develop the ability to gather, integrate, and implement these resources to improve organizational processes. Public sector organizations have to be agile and flexible to meet society's dynamic demands. In this sense, IT management and creating an organizational environment facilitating innovation are crucial measures. These organizations must learn to cultivate IT capabilities and innovativeness to improve their performance and create public value. Thus, this study aims to identify the existing relationships between innovativeness, IT capabilities, IT reconfiguration capability, and organizational performance in the public sector. The research analyzed data from 254 Brazilian public organizations of the most diverse sizes and sectors using structural equation modeling (SEM). The results indicated that the ability to reconfigure IT must be listed among the organizations' IT capabilities. Also, the findings suggest that IT capabilities foster organizations' innovativeness, and IT capabilities and innovativeness positively impact the organizations' performance. The study contributes to knowledge of innovation and IT capabilities by testing theoretical propositions identified in the context of the private sector but insufficiently assessed in the public sector. Finally, the study points out ways for public managers to better prepare their institutions to face constantly changing environments.

Resumen En vista del creciente volumen de recursos invertidos anualmente en tecnología de la información, las organizaciones del sector público deben tener cada vez más la capacidad de reunir, integrar e implementar recursos de TI para satisfacer las necesidades de los procesos organizacionales. Además, a las organizaciones públicas se les exige cada vez más ser más ágiles y flexibles para poder atender las demandas dinámicas de las sociedades. En este sentido, las organizaciones públicas deben ser capaces de gestionar y aplicar adecuadamente los recursos informáticos de los que disponen, así como crear entornos organizativos que permitan y favorezcan el florecimiento de la innovación. Es decir, deben aprender a cultivar las capacidades de TI y la innovación, con el objetivo de cumplir mejor su misión y crear valor público. Así, el objetivo de este estudio es identificar las relaciones existentes entre la innovación, las capacidades de TI, la capacidad de reconfiguración de TI y el desempeño organizacional, en el contexto del sector público. Para ello, se analizaron datos de 254 organizaciones públicas brasileñas de los más diversos tamaños y sectores, utilizando un enfoque de ecuaciones estructurales (SEM). Los resultados indicaron que la capacidad de reconfigurar la TI debe figurar entre las capacidades de TI de las organizaciones públicas, así como que las capacidades de TI desempeñan un papel en el fomento de la innovación de las organizaciones y que ambas (capacidades de TI e innovación) tienen un impacto positivo en el desempeño de las organizaciones. Al contrastar proposiciones teóricas identificadas en el contexto del sector privado, pero insuficientemente evaluadas en el sector público, el estudio agrega un bloque en la construcción de conocimiento sobre la capacidad de innovación y las capacidades de TI, además de señalar caminos para los gestores públicos sobre cómo pueden hacer que sus instituciones estén mejor preparadas para enfrentar entornos en constante cambio.

Resumo Tendo em vista o crescente volume de recursos investidos em tecnologia da informação a cada ano, as organizações do setor público devem cada vez mais ter a capacidade de reunir, integrar e implementar recursos de TI, a fim de atender às necessidades dos processos organizacionais. Além disso, as organizações públicas são cada vez mais exigidas a serem mais ágeis e flexíveis para atender às demandas dinâmicas das sociedades. Nesse sentido, as organizações públicas devem ser capazes de administrar e aplicar adequadamente os recursos de TI de que dispõem, bem como criar ambientes organizacionais que permitam e estimulem o florescimento da inovação. Ou seja, devem aprender a cultivar as capacidades de TI e a inovação, com o objetivo de melhor cumprir sua missão e criar valor público. Assim, o objetivo deste estudo é identificar as relações existentes entre inovatividade, capacidades de TI, capacidade de reconfiguração de TI e desempenho organizacional, no contexto do setor público. Para tanto, dados de 254 organizações públicas brasileiras, dos mais diversos portes e setores, foram analisados por meio de uma abordagem de equações estruturais (SEM). Os resultados indicaram que a capacidade de reconfigurar TI deve ser listada entre as capacidades de TI das organizações públicas, bem como que as capacidades de TI desempenham um papel no fomento da inovação das organizações e que ambas (as capacidades de TI e a inovatividade) têm um impacto positivo no desempenho das organizações. Ao testar proposições teóricas identificadas no contexto do setor privado, mas insuficientemente avaliadas no setor público, o estudo acrescenta um bloqueio na construção do conhecimento sobre capacidade de inovação e capacidades de TI, além de apontar caminhos para gestores públicos sobre como eles podem tornar suas instituições mais bem preparadas para enfrentar ambientes em constante mudança.