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This study presents an application of an Artificial Neural Network (ANN) to detect fluids in an annular flow regime using Prompt-Gamma Neutron Activation Analysis (PGNAA). The ANN was trained using gamma-ray spectra resulting from neutron interactions with chemical elements found in fluids typical of multiphase flow in oil exploration. These spectra were generated through mathematical simulation using the MCNP6 Monte Carlo computer code to model nuclear particle transport. A241Am-Be polyenergetic neutron source was simulated for these calculations. Several combinations of fluid fractions were developed to create a dataset used for both training and evaluation of the ANN. The ANN demonstrated robust generalization capabilities by accurately predicting the volume fraction of the three investigated fluids (saltwater, oil, and gas), even for cases not included in the training phase. The combination of ANN and PGNAA proved effective for analyzing multiphase systems, with over 92% of all showing errors of less than 5%.

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The most recent progress in reconstructive therapy for the management of periodontitis and peri-implantitis bone defects has relied on the development of highly porous biodegradable bioaerogels for guided bone regeneration. The objective of this work was to evaluate in vitro the osteoinduction of periodontal-originating cells (human dental follicle mesenchymal cells, DFMSCs) promoted by a nano-hydroxyapatite/chitosan (nHAp/CS) bioaerogel, which was purified and sterilized by a sustainable technique (supercritical CO2). Moreover, the in vivo bone regeneration capacity of the nHAp/CS bioaerogel was preliminarily assessed as a proof-of-concept on a rat calvaria bone defect model. The quantification of DNA content of DFMSCs seeded upon nHAp/CS and CS scaffolds (control material) showed a significant increase from the 14th to the 21st day of culture. These results were corroborated through confocal laser scanning microscopy analysis (CLSM). Furthermore, the alkaline phosphatase (ALP) activity increased significantly on the 21st day, similarly for both materials. Moreover, the presence of nHAp promoted a significantly higher expression of osteogenic genes after 21 days when compared to CS scaffolds and control. CLSM images of 21 days of culture also showed an increased deposition of OPN over the nHAp/CS surface. The in vivo bone formation was assessed by microCT and histological analysis. The in vivo evaluation showed a significant increase in bone volume in the nHAp/CS test group when compared to CS and the empty control, as well as higher new bone formation and calcium deposition within the nHAp/CS structure. Overall, the present study showed that the nHAp/CS bioaerogel could offer a potential solution for periodontal and peri-implant bone regeneration treatments since the in vitro results demonstrated that it provided favorable conditions for DFMSC proliferation and osteogenic differentiation, while the in vivo outcomes confirmed that it promoted higher bone ingrowth.

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La bibliometría es la aplicación de métodos estadísticos para analizar libros, artículos y otras publicaciones, especialmente científicos. Muy relacionada con la cienciometría e informetría, al punto de superponerse y confundirse. La bibliometría se refiere al estudio de la dinámica de las disciplinas reflejado en la producción de su literatura. Incluye desde el registro de cambios en la producción de una disciplina académica a lo largo del tiempo y entre países, hasta el problema de la colección bibliotecaria. En este artículo se explicarán algunos conceptos históricos, definiciones y objetivos de la bibliometría; así como las Leyes de la bibliometría; los tipos de análisis e indicadores bibliométricos más utilizados; para terminar con algunos ejemplos de diferentes tipos de estudios bibliométricos publicados, para que el lector pueda formarse una idea general de lo que puede hacer en este campo, aplicando estas metodologías a disciplinas quirúrgicas y otras también. El objetivo de este manuscrito fue generar un documento de estudio respecto de la bibliometría como alternativa para desarrollar investigación en cirugía y disciplinas afines.

Bibliometrics is the application of statistical methods to analyze books, articles and other publications, especially scientific ones. Closely related to scientometrics and informetrics, to the point of overlapping and confusing. Bibliometrics refers to the study of the dynamics of the disciplines reflected in the production of their literature. It includes everything from the record of changes in the production of an academic discipline over time and between countries or regions, to the problem of the library collection. In this article some historical concepts, definitions and objectives of bibliometrics will be explained; as well as the Laws of bibliometrics; the types of analysis and bibliometric indicators most used; to finish with some examples of different types of published bibliometric studies, so that the reader can form a general idea of what he can do in this field, applying these methodologies to surgical disciplines and others as well. The aim of this manuscript was to generate a study document regarding bibliometrics as an alternative to develop research in surgery and related disciplines.

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Las revistas depredadoras (RD), constituyen una gran amenaza para la publicación contemporánea, ya que ofrecen una publicación rápida de acceso abierto a cambio de tarifas sin procedimientos de revisión por pares para científicos jóvenes o inexpertos. Son compañías que priorizan el interés propio a expensas de la academia, caracterizándose por entregar información falsa o engañosa, distorsión de las mejores prácticas editoriales y de publicación, falta de transparencia y uso de tácticas de solicitud de manuscritos indiscriminadas y agresivas. El objetivo de este manuscrito fue generar un documento de estudio sobre las RD y secuestradas; así como de las conferencias depredadoras en cirugía.

Predatory journals (PD) are a major threat to contemporary publishing, as they offer rapid open access publication for fees without peer review procedures for young or inexperienced scientists. Are companies that prioritize self-interest at the expense of academia, characterized by providing false or misleading information, misrepresentation of publishing and editorial best practices, lack of transparency, and use of indiscriminate and aggressive manuscript solicitation tactics. The aim of this manuscript was to generate a study document regarding the PD, hijacked journals and predatory conferences in surgery.

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This study presents a methodology based on the dual-mode gamma densitometry technique in combination with artificial neural networks to simultaneously determine type and quantity of four different fluids (Gasoline, Glycerol, Kerosene and Fuel Oil) to assist operators of a fluid transport system in pipelines commonly found in the petrochemical industry, as it is necessary to continuously monitor information about the fluids being transferred. The detection system is composed of a 661.657 keV (137Cs) gamma-ray emitting source and two NaI(Tl) scintillation detectors to record transmitted and scattered photons. The information recorded in both detectors was directly applied as input data for the artificial neural networks. The proposed intelligent system consists of three artificial neural networks capable of predicting the fluid volume percentages (purity level) with 94.6% of all data with errors less than 5% and MRE of 1.12%, as well as identifying the pair of fluids moving in the pipeline with 95.9% accuracy.

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The eco-efficiency evaluation in wastewater treatment plants (WWTPs) is used to know and improve the environmental and economic efficiency of these processes, systems, products, and services. The eco-efficiency evaluations in WWTP contemplate the inputs to be minimized, the desirable results to be maximized, and the undesired results to be minimized. Data envelopment analysis (DEA) is a widely used method to evaluate the eco-efficiency of WWTPs; integrating several approaches in a single index, traditional DEA models do not take into account the uncertainty in the data. This study evaluates the eco-efficiency of a sample of Catalan WWTPs, considering the uncertainty of the data (DEA tolerance model), and it is for the first time that together with CO2, other greenhouse gas (GHG) such as CH4 and N2O are considered as part of the process outputs. GHG emissions were quantified using methods reported in the literature. Seven hundred twenty-nine eco-efficiency scores were estimated for each WWTP instead of a single score like conventional DEA models, analyzing optimistic and pessimistic scenarios. The WWTPs were classified according to the estimated eco-efficiency scores, accounting for the uncertainty in each of the scenarios, and demonstrating the changes in the performance of the WWTPs in the different scenarios. Only two WWTPs were eco-efficient in all the scenarios evaluated. This approach provides essential information to improve efficiency and innovation in the wastewater sector.

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SUMMARY: The aim of this study is to quantify muscular and connective tissue volumes of extraocular muscles (EOM) in humans with no ophthalmological disease using stereology. EOM from five cadaveric non-strabismic humans were obtained. The number of muscle fibers in 5,000 µm2 and volume density (Vv) of muscle and collagen were measured using stereology. Comparisons between antagonist EOM were conducted using Wilcoxon signed rank test for paired samples. A secondary analysis examining differences between pairs of EOM was also conducted. Bilateral tests were performed, and significance was set at 0.05. The horizontal rectus muscles (medial and lateral rectus) had the highest Vv of muscle and the lowest Vv of collagen. The inferior rectus muscle tended to have a fewer number of fibers per 5,000 µm2 than the rest of the EOM. However, these differences did not reach statistical significance. This is the first published study describing the normal histology of human EOM using stereology. Our investigation, through the quantification of the proportion of muscle and collagen tissue, as well as the number of muscle fibers in 5,000 µ2, establishes normal stereological parameters for EOM of humans without ophthalmological disease.

RESUMEN: El objetivo de este estudio es cuantificar el volumen de tejido muscular y conectivo de los músculos extraoculares en humanos sin enfermedad oftalmológica conocida utilizando estereología. Los músculos extraoculares fueron obtenidos de cinco cadáveres humanos sin estrabismo. El número de fibras musculares en 5.000 µm2 y la densidad de volumen (Vv) de músculo y colágeno fueron medidas usando estereología. Las comparaciones entre músculos extraoculares antagonistas se realizaron a través de la prueba de los rangos con signo de Wilcoxon para muestras pareadas. Un análisis secundario examinando diferencias entre pares de músculos extraoculares también fue llevado a cabo. Se realizaron pruebas bilaterales y la significancia fue fijada en 0,05. Los músculos rectos horizontales (recto medial y lateral) tuvieron el mayor Vv de músculo y el menor Vv de colágeno. El músculo recto inferior tuvo la tendencia a poseer menos número de fibras por 5.000 µm2 que el resto de los músculos extraoculares. No obstante, estas diferencias no llegaron a ser estadísticamente significativas. Este es el primer estudio publicado describiendo la histología normal de los músculos extraoculares usando estereología. Nuestra investigación, a través de la cuantificación de la proporción de tejido de músculo y colágeno, así como el número de fibras musculares en µm2, establece parámetros estereológicos normales para músculos extraoculares en humanos sin enfermedad oftalmológica.

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This study presents a method based on gamma-ray densitometry using only one multilayer perceptron artificial neural network (ANN) to identify flow regime and predict volume fraction of gas, water, and oil in multiphase flow, simultaneously, making the prediction independent of the flow regime. Two NaI(Tl) detectors to record the transmission and scattering beams and a source with two gamma-ray energies comprise the detection geometry. The spectra of gamma-ray recorded by both detectors were chosen as ANN input data. Stratified, homogeneous, and annular flow regimes with (5 to 95%) various volume fractions were simulated by the MCNP6 code, in order to obtain an adequate data set for training and assessing the generalization capacity of ANN. All three regimes were correctly distinguished for 98% of the investigated patterns and the volume fraction in multiphase systems was predicted with a relative error of less than 5% for the gas and water phases.

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The explicit breaking of the axial symmetry by quantum fluctuations gives rise to the so-called axial anomaly. This phenomenon is solely responsible for the decay of the neutral pion π0 into two photons (γγ), leading to its unusually short lifetime. We precisely measured the decay width Γ of the [Formula: see text] process. The differential cross sections for π0 photoproduction at forward angles were measured on two targets, carbon-12 and silicon-28, yielding [Formula: see text], where stat. denotes the statistical uncertainty and syst. the systematic uncertainty. We combined the results of this and an earlier experiment to generate a weighted average of [Formula: see text] Our final result has a total uncertainty of 1.50% and confirms the prediction based on the chiral anomaly in quantum chromodynamics.

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This research presents a methodology for volume fraction predictions in water-gas-oil multiphase systems based on gamma-ray densitometry and artificial neural networks. The simulated geometry uses a dual-energy gamma-ray source and dual-modality (transmitted and scattered beams). The Am-241 and Cs-137 sources and two NaI(Tl) detectors have been used in this methodology. Different data from the pulse height distribution were used to train the artificial neural network to evaluate the volume fraction prediction. The MCNPX code has been used to develop the theoretical model for stratified regime and to provide data for the artificial neural network. 5-layers feed-forward multilayer perceptron using backpropagation training algorithm and General Regression Neural Networks has been used with different designs. The artificial neural network design that presented the best results of volume fraction prediction has a mean relative error below 2.0%.

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About 50 years ago, Sarachick and Schappert [Phys. Rev. D. 1, 2738-2752 (1970)] showed that relativistic Thomson scattering leads to wavelength shifts that are proportional to the laser intensity. About 28 years later, Chen et al. [Nature 396, 653-655 (1998)] used these shifts to estimate their laser intensity near 1018 W/cm 2. More recently, there have been several theoretical studies aimed at exploiting nonlinear Thomson scattering as a tool for direct measurement of intensities well into the relativistic regime. We present the first quantitative study of this approach for intensities between 1018 and 1019 W/cm 2. We show that the spectral shifts are in reasonable agreement with estimates of the peak intensity extracted from images of the focal area obtained at reduced power. Finally, we discuss the viability of the approach, its range of usefulness and how it might be extended to gauge intensities well in excess of 1019 W/cm 2.

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Gender affirmation surgeries in male-to-female patient transitioning include breast augmentation, genital construction, and facial feminization surgery (FFS). FFS improves mental health and quality of life in transgender patients. The nose and forehead are critical in facial attractiveness and gender identity; thus, frontal brow reduction and rhinoplasty are a mainstay of FFS. The open approach to reduction of the frontal brow is very successful in the feminization of the face; however, risks include alopecia and scarring. Endoscopic brow reduction, in properly selected patients, is minimally invasive with excellent outcomes avoiding these risks. Since both reduction rhinoplasty and frontal brow reduction are routinely performed in FFS, a combined approach provides superior control over the nasal radix and profile when performing surgery on the frontal bone region first followed by nose reduction. We present a case series of four transwomen undergoing frontal bone reduction in combination with a reduction rhinoplasty. All had excellent results with one DVT that resolved with treatment. Transgender patients frequently require multiple operations during their transition increasing their hospital stay and costs. This combined approach offers superior control over the nasofrontal angle and is not only safe but reduces hospitalizations and costs and is a novel indication to reduce gender dysphoria.

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Hybrid scaffolds composed of hydroxyapatite (HAp), in particular in its nanometric form (n-HAp), and chitosan (CS) are promising materials for non-load-bearing bone graft applications. The main constraints of their production concern the successful implementation of the final purification/neutralization and sterilization steps. Often, the used purification strategies can compromise scaffold structural features, and conventional sterilization techniques can result in material's thermal degradation and/or contamination with toxic residues. In this context, this work presents a process to produce n-HAp/CS scaffolds mimicking bone composition and structure, where an innovative single step based on supercritical CO2 extraction was used for both purification and sterilization. A removal of 80% of the residual acetic acid was obtained (T = 75°C, p = 8.0 MPa, 2 extraction cycles of 2 h) giving rise to scaffolds exhibiting adequate interconnected porous structure, fast swelling and storage modulus compatible with non-load-bearing applications. Moreover, the obtained scaffolds showed cytocompatibility and osteoconductivity without further need of disinfection/sterilization procedures. Among the main advantages, the proposed process comprises only three steps (n-HAp/CS dispersion preparation; freeze-drying; and supercritical CO2 extraction), and the supercritical CO2 extraction show clear advantages over currently used procedures based on neutralization steps. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 965-975, 2018.

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OBJECTIVE: There is a lack of available information on the trajectories of attention-deficit/hyperactivity disorder (ADHD) dimensions during adulthood. This study investigates the course and the predictors of change for each ADHD domain in a clinical sample of adults with ADHD. METHOD: Adults with ADHD (n = 344) were followed up for 7 years, with a final retention rate of 66.0%. Trajectories of inattention, hyperactivity, and impulsivity and their potential predictors were examined. RESULTS: On average, symptoms declined in all ADHD domains during follow-up. Despite this, rises in inattentive, hyperactive, and impulsive symptoms were observed in approximately 13%, 25%, and 17% of patients respectively. Different predictors influenced the trajectory of each ADHD dimension. Oppositional defiant disorder and social phobia were associated with the maintenance of symptoms, while alcohol use disorder was associated with both maintenance and rise of symptoms. CONCLUSION: Unexpectedly, a rise in the symptoms after 7 years was not uncommon in adults with ADHD. Prevalent comorbidities have the potential to influence the neurodevelopment and the trajectory of ADHD. Therefore, such predictors should be investigated in population cohorts to better characterize the course of ADHD. Additionally, these findings may be relevant in prevention studies and in strategies for ADHD treatment.

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Essentials In vivo function of platelets stored at various conditions was studied in normo- and hypotension. Refrigerated platelets stored up to 5 days performed as well as those stored at room temperature. Platelet adhesion and thrombus formation were higher in ruptured vessels of hemorrhaged animals. In vivo data suggest that refrigerated platelets are hemostatically effective during hypotension. SUMMARY: Background There is renewed interest in the therapeutic use of cold-stored platelets for bleeding patients. However, critical information is absent or partially available in vitro. Therefore, thrombus formation and platelet adhesion were studied in vivo, in situ, using bleeding and thrombosis models in instrumented rats, and confocal intravital videomicroscopy. Objectives We tested the hypothesis that refrigerated (4 °C) platelets (stored for 24 h or 5 days) participated in thrombus formation as well as platelets stored at room temperature (RT, 22 °C). This hypothesis was tested in normovolemia and hemorrhagic hypotension. Methods & Results After fluorescently-labeled platelet infusion, endothelial injury and vessel rupture were laser-induced in cremaster microvessels and platelet adhesion in > 230 developing thrombi was evaluated. Blood samples were collected for biochemistry and coagulation assays while multiple systemic physiologic parameters were recorded. Hemorrhagic hypotension study animals were subjected to 40% hemorrhage, leading to hypotension and hemodilution, during in vivo platelet adhesion assessments. The fluorescence intensity associated with labeled platelet adherence provided a quantitative index of adhesion. Cold-stored platelets performed as well as those stored at RT in normovolemic animals. During hypotension, cold-stored platelets still performed as well as RT-stored platelets, whereas platelet adhesion and thrombus formation were increased relative to normovolemic animals, in bleeding model experiments. Conclusions We found the methodology suitable for evaluating platelet function in vivo after different storage conditions in fully monitored animals. Refrigerated platelets (stored up to 5 days) participated as well as RT-stored platelets in thrombi formed after hemorrhage, suggesting that refrigerated platelets are effective during hypotensive situations.

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OBJECTIVES: To determine efficacy and safety of withholding antimicrobials in children with cancer, fever and neutropenia (FN) with a demonstrated respiratory viral infection. METHODS: Prospective, multicentre, randomized study in children presenting with FN at five hospitals in Santiago, Chile, evaluated at admission for diagnosis of bacterial and viral pathogens including PCR-microarray for 17 respiratory viruses. Children positive for a respiratory virus, negative for a bacterial pathogen and with a favourable evolution after 48 h of antimicrobial therapy were randomized to either maintain or withhold antimicrobials. Primary endpoint was percentage of episodes with uneventful resolution. Secondary endpoints were days of fever/hospitalization, bacterial infection, sepsis, admission to paediatric intensive care unit (PICU) and death. RESULTS: A total of 319 of 951 children with FN episodes recruited between July 2012 and December 2015 had a respiratory virus as a unique identified microorganism, of which 176 were randomized, 92 to maintain antimicrobials and 84 to withdraw. Median duration of antimicrobial use was 7 days (range 7-9 days) versus 3 days (range 3-4 days), with similar frequency of uneventful resolution (89/92 (97%) and 80/84 (95%), respectively, not significant; OR 1.48; 95% CI 0.32-6.83, p 0.61), and similar number of days of fever (2 versus 1), days of hospitalization (6 versus 6) and bacterial infections throughout the episode (2%-1%), with one case of sepsis requiring admission to PICU in the group that maintained antimicrobials, without any deaths. CONCLUSIONS: The reduction of antimicrobials in children with FN and respiratory viral infections, based on clinical and microbiological/molecular diagnostic criteria, should favour the adoption of evidence-based management strategies in this population.

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This work presents a new methodology for density prediction of petroleum and derivatives for products' monitoring application. The approach is based on pulse height distribution pattern recognition by means of an artificial neural network (ANN). The detection system uses appropriate broad beam geometry, comprised of a (137)Cs gamma-ray source and a NaI(Tl) detector diametrically positioned on the other side of the pipe in order measure the transmitted beam. Theoretical models for different materials have been developed using MCNP-X code, which was also used to provide training, test and validation data for the ANN. 88 simulations have been carried out, with density ranging from 0.55 to 1.26gcm(-3) in order to cover the most practical situations. Validation tests have included different patterns from those used in the ANN training phase. The results show that the proposed approach may be successfully applied for prediction of density for these types of materials. The density can be automatically predicted without a prior knowledge of the actual material composition.