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A new algorithm for the determination of equilibrium structures suitable for metal nanoclusters is proposed. The algorithm performs a stochastic search of the minima associated with the nuclear potential energy function restricted to a sphere (similar to the Thomson problem), in order to guess configurations of the nuclear positions. Subsequently, the guessed configurations are further optimized driven by the total energy function using the conventional gradient descent method. This methodology is equivalent to using the valence shell electron pair repulsion model in guessing initial configurations in the traditional molecular quantum chemistry. The framework is illustrated in several clusters of increasing complexity: Cu7, Cu9 and Cu11 as benchmark systems and Cu38 and Ni9 as novel systems. New equilibrium structures for Cu9, Cu11, Cu38 and Ni9 are reported. [ABSTRACT FROM AUTHOR]

A numerical simulation of the intake and compression stroke and fuel spray and combustion in a direct injection compression ignition engine was performed using the Converge CFD software. For this purpose, the Reynolds Average Navier-Stokes (RANS) k-e RNG model and an n-dodecane kinetic mechanism were used in order to obtain the flow fields in the cylinder and to perform the breakup time analysis of the Kelvin-Helmholtz model in the variables related to the spray and combustion. The turbulent flow inside the cylinder was analysed, obtaining consistent results with experimental pressure data and other research authors. The droplet breakup time is evaluated as a function of the breakup time constant (B1), the initial droplet radius (ro), the wavelength (ΛKH) and the maximum growth rate (ΩKH). The results indicate that the numerical method and the models used in this work are adequate to perform subsequent representative combustion analyses with values of B1=7. It was possible to show that the formation of the species OH is greater for low values of B1. Also, higher values of the breakup time, variables such as temperature, pressure, fuel evaporation, ignition delay, and species formation are affected. [ABSTRACT FROM AUTHOR]

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Se estableció la dependencia espacial de Frankliniellaoccidentalis (Pergande) en un cultivo de fresa bajo cubierta en la Sabana de Bogotá. Se monitorearon las poblaciones de trips por doce semanas, en un área de 8 x 13 cuadrantes (cada cuadrante tenia un área de 8 x 4 m), tomando tres flores por cuadrante. El análisis de datos fue hecho con los programas Surfer y GS+/386, usados en geoestadística, los cuales se basan en el análisis de semivariogramas y correlogramas. Analizamos O;45; 90 y 135 grados de direccionalidad. Se encontraron dependencias espacialesen tres de las doce semanas y éstas indicaron que la dependencia espacial de las poblaciones de trips demostraron limites de uno hasta seis cuadrantes y fueron más frecuentes en O y 45 grados de direccionalidad. No se observó dependencia a 90 grados. Inicialmente, las colonias de trips fueron agregadas, pero cambiaron su disposición espacial al azar a través del tiempo, debido a que los individuos se mueven invadiendo otros cuadrantes. Finalmente, discutimos las importancia de la dependencia espacial de las poblaciones como una herramienta para el manejo de plagas.Spatial dependence of Frankliniella occidentalis (Pergande) in a covered strawberry crop was established at Bogota plateau. Thrips populations were monitored for 12 weeks in an area of eight by 13 quadrants (each quadrant of 8 x 4 m), taking three flowers per quadrant. Data analysis was done with Surfer and GS+/386 programs. Geostatistics, based on semivariogram and correlogram analyses were used. There were analyzed O, 45, 90, and 135 degreed of directionality. Spatial dependence were found in three ofthe twelveweeks and they indicated that spatial dependence of thripspopulations showed boundaries from one to six quadrants and were more frequent in Oand 45 degrees of directionality. No dependence was observed at 90 degrees. InitialIy, the thrips colonies were aggregated but, in time, changed this aggregated pattern toward a random pattern due to thrips movement to neighboring quadrants. Finally, we discuss the importance of spatial dependence as a tool for thrips management.

This article presents some interesting and polemical reflections about the Central Bank, the degree of credibility of its policies, the setting of goals in matters of monetary and exchange rate policy, the use of available instruments, and the trade-off between inflation and unemployment. For the author, autonomy is a necessary but not sufficient condition for achieving a lower rate of inflation. The struggle against inflation requires a large degree of social support, coordination between all the economic institutions of the State, and the responsibility of private institutions. The problem of dynamic inconsistency between credibility and results would be resolved when there is recogni tion of the superiori ty of an adjustable rule, in which credibility would be the result of a dynamic process of mutual teaching and learning between economic agents and the Central Bank, and in which economic policy instruments achieve a greater stability beca use a short term vision is transcended.En este artículo se presentan interesantes y polémicas reflexiones sobre la autonomía del Banco Central, el grado de credibilidad de sus políticas, la fijación de metas en materia de de política monetaria y cambiaria, el uso de instrumentos disponibles y el trade-off entre la inflación y el desempleo. Para el autor, la autonomía es una condición necesaria pero no suficiente para lograr una menor tasa de inflación. La lucha contra la inflación requiere de un gran respaldo social, de la coordinación entre todas las instituciones económicas del Estado y la responsabilidad de las entidades privadas. El problema de la inconsistencia dinámica entre credibilidad y resultados se resolvería cuando se reconozca la superioridad de una regla ajustable en donde la credibilidad sea el resultado de un proceso dinámico de aprendizaje y enseñanza mutua entre los agentes económicos y el Banco Central, y donde los instrumentos de política económica logren una mayor estabilidad debido a que se trasciende la visión cortoplacista.

Conferencia dictada en la Biblioteca Luis Ángel Arango con ocasión del homenaje a Lauchlin Currie, Organizada por la Facultad de Ciencias Económicas de la Universidad Nacional y la Fundación Fines.

Se estudió la estructura y la composición de arañas orbitelares (Araneae: Orbiculariae)en un bosque húmedo subtropical de la Sierra Nevada de Santa Marta. Los muestreosse realizaron en cuatro jornadas diurnas y nocturnas, que abarcaron las dos estacionessecas y las dos lluviosas, entre marzo y octubre de 2006. Se emplearon métodosde recolección manual, barrido con red entomológica y agitación de follaje. Serecolectaron 496 arañas orbitelares pertenecientes a seis familias y 35 morfoespecies.Araneidae fue la familia más rica en especies y la más abundante, Nephilidae yAnapidae fueron las menos ricas en especies y Nephilidae la menos abundante. Laaraneofauna orbitelar mostró preferencia por los microhábitats de vegetación arbustivay herbácea respectivamente. La araneofauna presentó mayor abundancia diurna conrelación a la abundancia nocturna. La composición y estructura de la comunidad dearañas orbitelares parecen estar relacionadas con el régimen climático. La distribuciónde abundancia de especies se ajustó al modelo de distribución log-normal lo quesugiere que la comunidad de arañas orbitelares es estable y se encuentran en relativoequilibrio.

no pretendemos movernos --o deslizarnos- sobre las curvas de oferta y demanda de trabajo en busca de un imaginario punto de equilibrio en el cual se establece una cierta relación entre utilidad y desutilidad del trabajo, o bien, se espera justamente que la tasa de salario, normal y eficiente, compense el esfuerzo marginal del último trabajador. y como consecuencia de lo anterior, no estimamos que lo más importante en el análisis sea la mecánica de demandas y ofertas en juego que responden elástica o inelásticamente a ciertas señales del mercado, -supuestas unas condiciones institucionales y dados unos parámetros de comportamiento. Pensamos que ese reino de las cosas oculta más de lo que pretende aclarar. Por el contrario, esas condiciones institucionales y estos parámetros de comportamiento son fundamentales para la interpretación de los hechos. Dicho de otra forma, además de tener en cuenta qué características adopta el "juego", hay que enfocar su misma naturaleza así como las reglas a que da Jugar. Para estos propósitos, resulta secundario el estudio micro económico de los ajustes en el margen.

Para mi intervención he considerado apropiado referirme alesquema básico que ha orientado el diseño del Plan de Desarrollo del actual gobierno, denominado PLAN DE ECONOMIA SOCIAL. Mediante este esquema se ha pretendido dar un gran paso adelante en la formulación de un nuevo modelo de desarrollo. Por esta razón, el tema está íntimamente relacionado con los objetivos del seminario, más aún cuando se trata de un plan oficial que ya se ha puesto en marcha y que puede, por consiguiente, constituir una valiosa experiencia para los estudiosos de los problemas del desarrollo y para quienes buscan alternativas en este proceso.

El objetivo del presente ensayo es efectuar una discusión, ciertamente. en forma breve, sobre los principales paradigmas del desarrollo, contraponer sus tesis centrales y evaluar sus alcances frente a los hechos que pretenden explicar e interpretar. Originalmente este trabajo se presentó como ponencia en el II Congreso de Economistas de la Universidad Nacional, a finales de 1981. A partir de entonces ha recibido diversos comentarios y críticas (tanto positivos como negativos) a las versiones de difusión limitada que han circulado en distintas universidades. A pesar de ello, y tal vez debido a ello, el autor considera útil publicarlo en su forma original, a la espera de poder contrastar un número más amplio de opiniones.

Background: Motivation for the study. There are few clinical and survival studies in Peru on thyroid cancer., Background: Main findings. Between the years 2010 to 2020, differentiated thyroid cancer was more frequent in women with early-stage disease, but survival was lower at five years compared to reports from other countries., Background: Implications. Thyroid cancer has increased in recent decades worldwide. It is important to have specialized and decentralized centers for the initial management and follow-up of these patients to avoid long-term complications or fatal outcomes and to have updated epidemiological information., Background: This study aimed at studying the clinical and anatomopathological characteristics, treatment and survival of patients with differentiated thyroid cancer. A retrospective cohort study was conducted with data from 150 patients from a Peruvian hospital between the years 2010 to 2020. Characteristics and survival (Kaplan-Meier method) were described. The mean age was 48.3 years, 130 participants (86.7%) were women and the most frequent histologic type was papillary 94.6%. Of the participants, 74.2% had TNM stage I, 70.7% had total thyroidectomy and 68.7% received radioactive iodine. Overall survival at 5 years was 89.3%, being lower in those with TNM stage IV and higher in those who used radioactive iodine. In conclusion, in a hospital in Cusco, differentiated thyroid cancer was more frequent in women and survival was lower compared to reports from other countries.

Introduction: Anatomic distribution of adipose tissue has demonstrated variable associations with hypercoagulability. Utilizing a retrospective analysis of a previously enrolled prospective cohort, we assessed computed tomography (CT) scan-based anthropometric and volumetric measures of adiposity as predictors of postinjury hypercoagulability., Methods: Segmentation analysis of arrival CT scans in significantly injured patients at a single level-I trauma center enrolled from December 2017 to August 2021 were analyzed for anthropometric indices of waist circumference (WC) and sagittal abdominal diameter (SAD), and volumetric parameters of visceral adipose tissue, superficial/deep subcutaneous adipose tissue, psoas/paravertebral muscle volume, and abdominal wall muscle volume. Associations with thromboelastography (TEG) were explored., Results: Data from 91 patients showed strong correlations between body mass index and standard anthropometric measures of WC and SAD (P < 0.001); calculated volumes of subcutaneous adipose tissue and visceral adipose tissue (P < 0.001); and ratios of subcutaneous adipose:psoas muscle (SP ratio) and visceral adipose:psoas muscle ratio (both with P < 0.001, respectively). Correlation between TEG maximal amplitude (MA) and body mass index and SAD were not significant, with only weak correlation between TEG-MA and WC (r = 0.238, P = 0.041). Moderate but significant correlations existed between SP ratio and TEG-MA (r = 0.340, P = 0.005), but not visceral adipose:psoas muscle ratio (r = 0.159, P = 0.198). The relationship between TEG-MA and SP ratio remained significant when adjusted for injury severity score and lactate level (b = 0.302, P = 0.001)., Conclusions: SP ratio is more strongly correlated with TEG-MA than standard obesity measures, and independently predicts increasing clot strength/stability after injury. Coagulation-relevant measures of sarcopenic obesity can be measured on CT scan, and may be used to optimize thromboprophylaxis strategies for obese injured patients., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: There are no data on the association of type of pneumonia and long-term mortality by the type of pneumonia (COVID-19 or community-acquired pneumonia [CAP]) on long-term mortality after an adjustment for potential confounding variables. We aimed to assess the type of pneumonia and risk factors for long-term mortality in patients who were hospitalized in conventional ward and later discharged., Methods: Retrospective analysis of two prospective and multicentre cohorts of hospitalized patients with COVID-19 and CAP. The main outcome under study was 1-year mortality in hospitalized patients in conventional ward and later discharged. We adjusted a Bayesian logistic regression model to assess associations between the type of pneumonia and 1-year mortality controlling for confounders., Results: The study included a total of 1,693 and 2,374 discharged patients in the COVID-19 and CAP cohorts, respectively. Of these, 1,525 (90.1%) and 2,249 (95%) patients underwent analysis. Until 1-year follow-up, 69 (4.5%) and 148 (6.6%) patients from the COVID-19 and CAP cohorts, respectively, died ( p  = 0.008). However, the Bayesian model showed a low probability of effect (PE) of finding relevant differences in long-term mortality between CAP and COVID-19 (odds ratio 1.127, 95% credibility interval 0.862-1.591; PE = 0.774)., Conclusion: COVID-19 and CAP have similar long-term mortality after adjusting for potential confounders., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Méndez, González-Jiménez, Latorre, Mengot, Zalacain, Ruiz, Serrano, España, Uranga, Cillóniz, Hervás, Torres, Menéndez, NEUMONAC and RECOVID.)

Understanding the nature of the interaction between mercury(II) ions, Hg 2+ , and water molecules is crucial to describe the stability and chemical behavior of structures formed during solvation, as well as the conditions that favor the Hg 2+ coordination or inducing water hydrolysis. In our study, we explored exhaustively the potential energy surface of Hg 2+ with up to six water molecules. We analyzed electronic and Gibbs free energies, binding, and nuclear magnetic resonance parameters. We used the zeroth-order regular approximation Hamiltonian, including scalar and spin-orbit relativistic corrections for free energy calculations and geometry optimizations to explore the interplay between electron correlation and relativistic effects. We analyzed intermolecular interactions with energy decomposition analysis, quantum theory of atoms in molecules, and natural bond orbital. Additionally, we used the four-component Dirac Hamiltonian to compute solvent effect on the magnetic shielding and J -coupling constants. Our results revealed that the water hydrolysis by Hg 2+ requires a minimum of three water molecules. We found that the interaction between Hg 2+ and water molecules is an orbital interaction due to relativistic effects and the most stable structures are opened-shape clusters, reducing the number of oxygen-mercury contacts and maximizing the formation of hydrogen bonds among water molecules. In these types of clusters, Hg 2+ promotes the water hydrolysis over coordination with oxygen atoms. However, when we considered the change associated with the transfer of a cluster from the ideal gas to a solvated system, our solvation free energy analysis revealed that closed-shape clusters are more favorable, maximizing the number of oxygen-mercury contacts and reducing the formation of hydrogen bonds among water molecules. This finding suggests that, under room conditions, the coordination of Hg 2+ is more favorable than hydrolysis. Our results have significant implications for understanding Hg 2+ behavior in water, helping to develop targeted strategies for mercury remediation and management, and contributing to advancements in the broader field of environmental chemistry.

Objective: Surgery is the cornerstone of craniosynostosis treatment. In this study, two widely accepted techniques are described: endoscope-assisted surgery (EAS) and open surgery (OS). The authors compared the perioperative and reconstructive outcomes of EAS and OS in children ≤ 6 months of age treated at the Napoleón Franco Pareja Children's Hospital (Cartagena, Colombia)., Methods: According to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement, patients with defined criteria who underwent surgery to correct craniosynostosis between June 1996 and June 2022 were retrospectively enrolled. Demographic data, perioperative outcomes, and follow-up were obtained from their medical records. Student t-tests were used for significance. Cronbach's α was used to assess agreement between estimated blood loss (EBL). Spearman's correlation coefficient and the coefficient of determination were used to establish associations between the results of interest, and the odds ratio was used to calculate the risk ratio of blood product transfusion., Results: A total of 74 patients met the inclusion criteria; 24 (32.4%) belonged to the OS group and 50 (67.6%) to the EAS group. There was a high interobserver agreement quantifying the EBL. The EBL, transfusion of blood products, surgical time, and hospital stay were shorter in the EAS group. Surgical time was positively correlated with EBL. There were no differences between the two groups in the percentage of cranial index correction at 12 months of follow-up., Conclusions: Surgical correction of craniosynostosis in children aged ≤ 6 months by EAS was associated with a significant decrease in EBL, transfusion requirements, surgical time, and hospital stay compared with OS. The results of cranial deformity correction in patients with scaphocephaly and acrocephaly were equivalent in both study groups.

As early as 1975, Pitzer suggested that copernicium, flerovium, and oganesson are volatile substances behaving like noble gas because of their closed-shell configurations and accompanying relativistic effects. It is, however, precarious to predict the chemical bonding and physical behavior of a solid by knowledge of its atomic or molecular properties only. Copernicium and oganesson have been analyzed very recently by our group. Both are predicted to be semiconductors and volatile substances with rather low melting and boiling points, which may justify a comparison with the noble gas elements. Here, we study closed-shell flerovium in detail to predict its solid-state properties, including the melting point, by decomposing the total energy into many-body forces derived from relativistic coupled-cluster theory and from density functional theory. The convergence of such a decomposition for flerovium is critically analyzed, and the problem of using density functional theory is highlighted. We predict that flerovium in many ways does not behave like a typical noble gas element despite its closed-shell 7p 1/2 2 configuration and resulting weak interactions. Unlike the case of noble gases, the many-body expansion in terms of the interaction energy does not converge smoothly. This makes the accurate prediction of phase transitions very difficult. Nevertheless, a first prediction by Monte Carlo simulation estimates the melting point at 284 ± 50 K. Furthermore, calculations for the electronic bandgap suggests that flerovium is a semiconductor similar to copernicium.

Background: Difficult airway is a clinical situation in which a trained anesthesiologist experiences trouble with facemask ventilation and/or laryngoscopy and/or intubation. Poor identification of at-risk patients has been identified as one of the causes of difficult airway management., Objectives: We aimed to review the literature regarding the use of wristbands to identify adult patients with known or predicted difficult airway in hospitals., Methods: We searched Web of Science (WoS), Scopus, MEDLINE and OVID following the stages described by the PRISMA Extension for Scoping Reviews (PRISMA-ScR). We used a combination of MeSH terms and non-controlled vocabulary regarding the use of difficult airway wristbands in adults. Three researchers independently reviewed the full texts and selected the papers to be included based on the inclusion criteria., Results: Our search generated 334 articles after removing duplicates. After reviewing full text articles, only seven studies were included. Here we found that most were from the United States, in which the authors report the use of in-patients' wristbands in adults. According to the authors, the use of wristbands is being implemented as a measure of improved quality and safety of in-patients with difficult airway either known or suspected., Conclusions: The identification with wristbands of a difficult airway at an appropriate time is an identification strategy can have a low cost but a high impact on morbidity. It is pertinent to develop a methodology such as the use of wristbands, that allows a good classification and identification of patients with difficult airway in hospitals from Latin America., (Copyright © 2021 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.)

Background: Ertapenem has proven to be effective for extended-spectrum beta-lactamases-producing Enterobacteriaceae but lacks activity against non-fermenters; de-escalation to this antibiotic may reduce the selection of resistance to Pseudomonas aeruginosa and improve clinical outcomes., Aim: To evaluate the clinical impact of de-escalation from broad-spectrum anti-pseudomonal agents to ertapenem, a non-pseudomonal antibiotics for Enterobacteriaceae infections in critically-ill patients., Methods: We conducted a prospective cohort study in adult patients admitted to intensive care units (ICUs) who had Enterobacteriaceae infections and were de-escalated from empiric anti-pseudomonal coverage to non-pseudomonal antibiotics. Cox proportional hazards models were performed comparing all-cause mortality and length of hospital stay between patients who remained on anti-pseudomonal coverage versus those who were de-escalated to ertapenem., Results: 105 patients in the anti-pseudomonal group were compared to 148 patients in the ertapenem de-escalation group. De-escalation was associated with lower all-cause mortality compared to patients who remained on anti-pseudomonal coverage (adjusted Hazard Ratio 0.24; 95% CI: 0.12-0.46). The length of ICU stay was similar between the groups., Discussion: ICU patients with Enterobacteriaceae infections de-escalated to ertapenem therapy had better outcomes compared to patients who remained on broad-spectrum, anti-pseudomonal therapy, suggesting that de-escalation is a safe approach amongst ICU patients.

Aim: Development of MRI sequences and processing methods for the production of images appropriate for direct use in stereotactic radiosurgery (SRS) treatment planning., Background: MRI is useful in SRS treatment planning, especially for patients with brain lesions or anatomical targets that are poorly distinguished by CT, but its use requires further refinement. This methodology seeks to optimize MRI sequences to generate distortion-free and clinically relevant MR images for MRI-only SRS treatment planning., Materials and Methods: We used commercially available SRS MRI-guided radiotherapy phantoms and eight patients to optimize sequences for patient imaging. Workflow involved the choice of correct MRI sequence(s), optimization of the sequence parameters, evaluation of image quality (artifact free and clinically relevant), measurement of geometrical distortion, and evaluation of the accuracy of our offline correction algorithm., Results: CT images showed a maximum deviation of 1.3 mm and minimum deviation of 0.4 mm from true fiducial position for SRS coordinate definition. Interestingly, uncorrected MR images showed maximum deviation of 1.2 mm and minimum of 0.4 mm, comparable to CT images used for SRS coordinate definition. After geometrical correction, we observed a maximum deviation of 1.1 mm and minimum deviation of only 0.3 mm., Conclusion: Our optimized MRI pulse sequences and image correction technique show promising results; MR images produced under these conditions are appropriate for direct use in SRS treatment planning.

Purpose: To evaluate precision of a software-based liver surface nodularity (LSN) score derived from CT images., Methods: An anthropomorphic CT phantom was constructed with simulated liver containing smooth and nodular segments at the surface and simulated visceral and subcutaneous fat components. The phantom was scanned multiple times on a single CT scanner with adjustment of image acquisition and reconstruction parameters (N = 34) and on 22 different CT scanners from 4 manufacturers at 12 imaging centers. LSN scores were obtained using a software-based method. Repeatability and reproducibility were evaluated by intraclass correlation (ICC) and coefficient of variation. Using abdominal CT images from 68 patients with various stages of chronic liver disease, inter-observer agreement and test-retest repeatability among 12 readers assessing LSN by software- vs. visual-based scoring methods were evaluated by ICC., Results: There was excellent repeatability of LSN scores (ICC:0.79-0.99) using the CT phantom and routine image acquisition and reconstruction parameters (kVp 100-140, mA 200-400, and auto-mA, section thickness 1.25-5.0 mm, field of view 35-50 cm, and smooth or standard kernels). There was excellent reproducibility (smooth ICC: 0.97; 95% CI 0.95, 0.99; CV: 7%; nodular ICC: 0.94; 95% CI 0.89, 0.97; CV: 8%) for LSN scores derived from CT images from 22 different scanners. Inter-observer agreement for the software-based LSN scoring method was excellent (ICC: 0.84; 95% CI 0.79, 0.88; CV: 28%) vs. good for the visual-based method (ICC: 0.61; 95% CI 0.51, 0.69; CV: 43%). Test-retest repeatability for the software-based LSN scoring method was excellent (ICC: 0.82; 95% CI 0.79, 0.84; CV: 12%)., Conclusion: The software-based LSN score is a quantitative CT imaging biomarker with excellent repeatability, reproducibility, inter-observer agreement, and test-retest repeatability.

Purpose The definition of radiotherapy target volume is a critical step in treatment planning for all tumor sites. Conventional magnetic resonance imaging (MRI) pulse sequences are used for the definition of the gross target volume (GTV) and the contouring of glioblastoma multiforme (GBM) and meningioma. We propose the use of multiparametric MRI combined with radiomic features to improve the texture-based differentiation of tumor from edema for GTV definition and to differentiate vasogenic from tumor cell infiltration edema. Methods Twenty-five patients with brain tumor and peritumoral edema (PTE) were assessed. Of the enrolled patients, 17 (63 ± 10 years old, six female and 11 male patients) were diagnosed with GBM and eight (64 ± 14 years old, five female and three male patients) with meningioma. A 3 Tesla (3T) MRI scanner was used to scan patients using a 3D multi-echo Gradient Echo (GRE) sequence. After the acquisition process, two experienced neuroradiologists independently used an in-house semiautomatic algorithm to conduct a segmentation of two regions of interest (ROI; edema and tumor) in all patients using functional MRI sequences, apparent diffusion coefficient (ADC), and dynamic contrast-enhanced MRI (DCE-MRI), as well as anatomical MRI sequences-T1-weighted, T2-weighted and fluid-attenuated inversion recovery (FLAIR). Radiomic (computer-extracted texture) features were extracted from all ROIs through different approaches, including first-, second-, and higher-order statistics, both with and without normalization, leading to the calculation of around 300 different texture parameters for each ROI. Based on the extracted parameters, a least absolute shrinkage and selection operator (LASSO) analysis was used to isolate the parameters that best differentiated edema from tumors while irrelevant parameters were discarded. Results and conclusions The parameters chosen by LASSO were used to perform statistical analyses which allowed identification of the variables with the best discriminant ability in all scenarios. Receiver operating characteristic results showcase both the best single discriminator and the discriminant capacity of the model using all variables selected by LASSO. Excellent results were obtained for patients with GBM with all MRI sequences, with and without normalization; a T1-weighted sequence postcontrast (T1W+C) with normalization offered the best tumor classification (area under the curve, AUC > 0.97). For patients with meningioma, a good model of tumor classification was obtained through the T1-weighted sequence (T1W) without normalization (AUC > 0.71). However, there was no agreement between the results of both radiologists for some MRI sequences analyzed for patients with GBM and meningioma. In conclusion, a small subset of radiomic features showed an excellent ability to distinguish edema from tumor tissue through its most discriminating features., Competing Interests: The authors have declared that no competing interests exist.

Transarterial radioembolization using yttrium-90 microspheres is an established and effective treatment for liver malignancies. Determining response to this treatment is difficult due to the radical changes that occur in tissue as a response to radiation. Though accurate assessment of treatment response is paramount for proper patient disposition, there is currently no standardized assessment protocol. Current methods of assessment often consider changes in size, necrosis, vascularity, fluorodeoxyglucose-positron emission tomography FDG-PET metabolic activity, and diffusion using diffusion-weighted magnetic resonance imaging (DWI). Current methods of assessment require a lag time of one to two months post-treatment to determine treatment effectiveness. This delay is a hindrance to obtaining better patient outcomes, giving rise to a need to identify markers for faster determination of treatment efficacy., Competing Interests: The authors have declared that no competing interests exist.

A staggering structural diversity for the microsolvation of F- with up to six water molecules is uncovered in this work. Given the structural variety and the proximity in energy among several local minima, we show here that in order to match available experimental data, statistical averages over contributing structures are needed, rather than assigning experimental values to isolated structures. Our results suggest that the formal charge in F- is strong enough as to induce partial and total dissociation of water molecules and to alter the nature of the surrounding network of water to water hydrogen bonds. We provide an extensive analysis of bonding interactions under the NBO and QTAIM formalisms, our main results suggest a complex interplay between ionic and covalent characters for the FH interactions as a function of the separation between the atoms.