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The use of advanced modulation and control schemes for power converters, such as a Feedback Quantizer and Predictive Control, is widely studied in the literature. This work focuses on improving the closed-loop modulation scheme called Feedback Quantizer, which is applied to a three-phase voltage source inverter. This scheme has the natural behavior of mitigating harmonics at low frequencies, which are detrimental to electrical equipment such as transformers. This modulation scheme also provides good tracking for the voltage reference at the fundamental frequency. On the other hand, the disadvantage of this scheme is that it has a variable switching frequency, creating a harmonic spectrum in frequency dispersion, and it also needs a small sampling time to obtain good results. The proposed scheme to improve the modulation scheme is based on a Discrete Space Vector with virtual vectors to obtain a better approximation of the optimal vectors for use in the algorithm. The proposal improves the conventional scheme at a high sampling time (200 µs), obtaining a THD less than 2% in the load current, decreases the noise created by the conventional scheme, and provides a fixed switching frequency. Experimental tests demonstrate the correct operation of the proposed scheme.

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Natural products and their semi-synthetic derivatives undoubtedly constitute an important source of therapeutic agents. Their importance lies in their own origin and evolution, since they have great chemical diversity, biochemical specificity, and pharmacological properties. Currently, there is a renewed interest in the development of methodologies capable of efficiently modifying the chemical structure of these bioactive platforms. In this work, the photoderivatization of the diterpene solidagenone was performed using a complexity-to-diversity-oriented approach. By exploring [2+2]-photocycloaddition, photoinduced-hydrogen abstraction, and photoxygenation reactions, a set of solidagenone derivatives was obtained, showing different ring fusions, side chain rearrangements, and modifications of the original furan ring's substitution pattern. The derivatives obtained were characterised by NMR methodologies. To evaluate the structural diversity of the labdane-derived compounds, their physicochemical properties, structural similarity, and chemical space were analysed. These results suggest that photochemical reactions are a useful tool for performing ring distortion transformations, generating derivatives of natural compounds with wide diversity, structural complexity, and with potential biological properties.

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El objetivo de este estudio fue determinar la relación entre creencias irracionales y sintomatología depresiva en estudiantes universitarios de Psicología en Honduras. Se utilizó un enfoque cuantitativo, un alcance descriptivo-correlacional y un diseño no experimental transversal correlacional. La muestra fue de 257 estudiantes universitarios de Psicología de dos universidades hondureñas. Para la recolección de datos se aplicó el Test de Creencias Irracionales y el Inventario de Depresión de Beck-II. Las principales creencias irracionales manifiestas por los estudiantes son culpabilización, altas autoexpectativas, influencia del pasado y evitación de problemas, y alrededor de un tercio sufre sintomatología depresiva de moderada a severa. Los estudiantes varones, menores de 31 años, pertenecientes a una universidad privada y que se encuentran solteros son los que tienen más altas creencias irracionales y mayores niveles de depresión, pero solo hay diferencia estadísticamente significativa entre el grupo etario y la sintomatología depresiva. Además, existe relación significativa entre creencias irracionales y cuatro de sus dimensiones (necesidad de aprobación, altas autoexpectativas, culpabilización e influencia del pasado) con sintomatología depresiva. Es urgente que las autoridades universitarias elaboren programas y servicios institucionales que prevengan y promuevan la salud mental, para disminuir los procesos mentales patológicos que pueden desencadenar problemas como el suicidio.

The objective of this study was to determine the relationship between irrational beliefs and depressive symptoms in university students of Psychology in Honduras. A quantitative approach, a descriptive-correlational scope and a non-experimental correlational cross-sectional design was used. The sample was 257 university students of Psychology from two Honduran universities. For the collection of data, the Irrational Beliefs Test and the Beck-II Depression Inventory were applied. The main irrational beliefs manifested by the students are guilt, high self-expectations, influence of the past and avoidance of problems, and about a third of the students suffer from moderate to severe depressive symptoms. Male students, under 31 years, attending a private university and who are single are those who have the highest irrational beliefs and higher levels of depression, but there is only a statistically significant difference between the age group and depressive symptomatology. In addition, there is a statistically significant relationship between irrational beliefs and four of its dimensions (need for approval, high self-expectations, guilt and influence of the past) with depressive symptoms. It is urgent that university authorities develop programs and institutional services that prevent and promote mental health, to reduce pathological mental processes that can trigger problems such as suicide.

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Este artículo describe los perfiles de personalidad de 95 adolescentes de la ciudad del Alto de La Paz. Los datos surgen del proceso empírico realizado en periodo de emergencia sanitaria por la pandemia por COVID -19. Los adolescentes en este contexto buscan nuevas e innovadoras maneras de afrontar esta realidad. Para eso se proyectan a partir de sus cualidades, habilidades, competencias y características que permiten la búsqueda de un proyecto de vida o la elección de una carrera universitaria. Se utilizó técnicas de investigación cuantitativa (Cuestionario Big Fives o Cinco Grandes) para reconocer los índices en cada dimensión, sub dimensión y escala de distorsión de la personalidad y se realizó un abordaje cualitativo en el reconocimiento de los perfiles de personalidad. Se observó que existe una tendencia mayor de adolescentes con predisposición a ser creativos e investigadores y no así realistas, sociales y dirigentes. La conclusión es que los datos permitirán a los adolescentes una perspectiva distinta en la elección de carreras universitarias convencionales.

This article describes the personality profiles of 165 adolescents from the City of Alto de La Paz. In times of health emergency it is a problem to set medium-term objectives. Teenagers must seek new and innovative ways to deal with this reality. For this, it is necessary to recognize the qualities, skills, competencies and characteristics of adolescents who are looking for a life project or the choice of a university career. Quantitative research techniques (Big Fives or Big Five Questionnaire) were used to recognize the levels in each dimension, sub-dimension and personality distortion scale and a qualitative approach was carried out in the recognition of personality profiles. It was observed that there is a greater tendency of adolescents with a predisposition to be creative and investigative and not so realistic, social and leaders. The conclusion is that the data will allow adolescents a different perspective in the choice of conventional university careers.

Este artigo descreve os perfis de personalidade de 165 adolescentes da cidade de Alto de La Paz. Em tempos de emergência sanitária é um problema estabelecer objetivos de médio prazo. Os adolescentes devem buscar formas novas e inovadoras de lidar com essa realidade. Para isso, é necessário reconhecer as qualidades, habilidades, competências e características dos adolescentes que buscam um projeto de vida ou a escolha de uma carreira universitária. Técnicas de pesquisa quantitativa (Big Fives ou Big Five Questionnaire) foram utilizadas para reconhecer os níveis em cada dimensão, subdimensão e escala de distorção de personalidade e uma abordagem qualitativa foi realizada no reconhecimento de perfis de personalidade. Observou-se que há uma maior tendência de adolescentes com predisposição a serem criativos e investigativos e não tão realistas, sociais e líderes. A conclusão é que os dados permitirão aos adolescentes uma perspectiva diferente na escolha das carreiras universitárias convencionais.

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It is commonly known-and previous studies have indicated-that time appears to last longer during unpleasant situations. This study examined whether a reciprocal statement can be made-that is, whether changes in the perception of time can influence our judgment (or rating) of a negative event. We used a temporal illusion method (Pomares et al. Pain 152, 230-234, 2011) to induce distortions in the perception of time. Two stimuli were presented for a constant time: a full clock, which stayed on the screen until its clock hand completed a full rotation (360°); and a short clock, in which the clock hand moved just three-quarters of the way (270°), thus suggesting a reduced interval duration. However, both stimuli were shown for the same amount of time. We specifically investigated (a) whether we could induce a temporal illusion with this simple visual manipulation, and (b) whether this illusion could change participants' ratings of a painful stimulus. In Experiment I (n = 22), to answer (a) above, participants were asked to reproduce the duration in which the different clocks were presented. In Experiment II (n = 30), a painful thermal stimulation was applied on participants' hands while the clocks were shown. Participants were asked to rate the perceived intensity of their pain, and to reproduce its duration. Results showed that, for both experiments, participants reproduced a longer interval after watching the full clock compared with the short clock, confirming that the clock manipulation was able to induce a temporal illusion. Furthermore, the second experiment showed that participants rated the thermal stimuli as less painful when delivered with the short clock than with the full clock. These findings suggest that temporal distortions can modulate the experience of pain.

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OBJECTIVES: This study aimed to evaluate the effect of different meditation practices on eating behavior, changes in body weight, and mental health. METHODS: A virtual questionnaire was used to evaluate meditation practices and current and prepandemic weights. The questionnaire comprised specific and validated instruments to evaluate body image (silhouette scale), eating behavior (21-item three-factor eating questionnaire), current sleep quality (Pittsburgh Sleep Quality Index), and anxiety (Beck Anxiety Inventory). Initially, data from all the respondents were assessed (n = 764). Mindfulness was the most common type of meditation practice in most Brazilian regions. RESULTS: Lower scores in uncontrolled eating (meditation practitioners = 32.19 ± 19.72 and non-meditation practitioners = 35.17 ± 20.50; P = 0.038) and higher weight loss (meditation practitioners = -0.77 ± 8.44 and non-meditation practitioners = 1.29 ± 6.39; P = 0.013) were observed among those who practiced some type of meditation. To verify the influence of weight, we analyzed the data of individuals who had body mass index ≥25 kg/m²; overweight individuals presented lower uncontrolled eating scores when they practiced meditation. However, no statistical difference was observed between meditation practitioners and non-practitioners when only adequate weight individuals were evaluated. The practice also influenced the perception of body image among men and resulted in lower uncontrolled eating scores on the 21-item three-factor eating questionnaire and greater weight loss during the pandemic among women. Those practicing meditation for >13 mo had a lower final score on the anxiety assessment instrument compared with those practicing for <12 mo (P = 0.002). CONCLUSIONS: The findings indicate that the inclusion of meditation practice as part of the management of overweight may reduce dysfunctional eating behaviors and negative emotions, thereby contributing to weight loss, especially in the long term.

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Abstract University students are particularly susceptible to suicidal ideation and behavior due to issues inherent to this vital lives' moment. The Rorschach test can help to understand these students' suffering. The objective was to evaluate perception, thinking, stress, and distress in the Rorschach test domains in university students attended at a public university mental health service, comparing students with suicidal ideation with those without it. A total of 36 students aged 18 or over were assessed. The instruments were: Rorschach Performance Assessment System (R-PAS), Columbia Suicide Severity Rating Scale (C-SSRS) and Self Report Questionnaire (SRQ-20). Two analyses were performed using Wilcoxon Mann-Whitney test, according to the presence of suicidal ideation in the last 30 days (SRQ-20) and in the last six months (C-SSRS). Statistically significant differences were found in the two analyses, indicative of greater perceptual distortion in students without suicidal ideation and of stress and distress in students with ideation.

Resumo Estudantes universitários são particularmente suscetíveis a ideação e comportamento suicidas decorrentes de problemas inerentes a este momento vital. O método de Rorschach pode contribuir na compreensão do sofrimento destes estudantes. O objetivo do estudo foi avaliar os domínios percepção, pensamento, estresse e angústia no Rorschach de estudantes universitários atendidos em serviço de saúde mental de universidade pública, comparando estudantes com ideação suicida com aqueles sem ideação. Foram avaliados 36 estudantes com 18 anos ou mais. Os instrumentos foram: Rorschach Performance Assessment System (R-PAS), Escala de Avaliação do Risco de Suicídio de Columbia (C-SSRS) e Self Report Questionnaire (SRQ-20). Foram realizadas duas análises com teste de Wilcoxon Mann-Whitney, segundo a presença de ideação nos últimos 30 dias (SRQ-20) e nos últimos 6 meses (C-SSRS). Foram observadas diferenças estatísticas significativas nas duas análises, indicativas de maior distorção perceptiva nos alunos sem ideação suicida e de angústia e estresse nos estudantes com ideação.

Resumen Estudiantes universitarios son particularmente susceptibles a ideación y comportamiento suicida debido a problemas inherentes a este momento vital. El Rorschach puede ayudar a comprender su sufrimiento. El objetivo fue evaluar los dominios percepción, pensamiento, estrés y angustia en el Rorschach de universitarios atendidos en un servicio de salud mental de universidad pública, comparando estudiantes con ideación suicida con aquellos sin esa ideación. Se evaluaron 36 estudiantes de pregrado y posgrado de 18 años o más. Los instrumentos fueron: Rorschach Performance Assessment System, Escala Columbia para Evaluar la Seriedad de la Ideación Suicida (C-SSRS) y Self Report Questionnaire (SRQ-20). Se realizaron dos análisis con Wilcoxon Mann-Whitney test, según la presencia de ideación en los últimos 30 días (SRQ-20) y en los últimos 6 meses (C-SSRS). Hubo diferencias estadísticamente significativas en los dos análisis, indicativas de mayor distorsión perceptiva en estudiantes sin ideación suicida y de angustia y estrés en estudiantes con ideación.

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Abstract Objective: Previous studies have shown that hearing function is also vulnerable to the effects of diabetes mellitus which can be shown by brainstem auditory evoked potential and distortion product otoacoustic emission recordings. This study aimed to investigate the changes of brainstem auditory evoked potential and distortion product otoacoustic emission in hyperglycemia and whether there is a relationship between reactive oxygen substances production and hearing deterioration in the rat model. Methods: 25 streptozotocin induced diabetic rats were divided into three groups: control, high blood glucose, and diabetes mellitus. Brainstem auditory evoked potential and distortion product otoacoustic emission were recorded, and thiobarbituric acid reactive substances levels were measured in the brainstem tissue. Results: At 8 kHz, the latencies of I, II, III, IV, and V brainstem auditory evoked potential waves in high blood glucose and diabetes mellitus groups were elongated, at 16 kHz, only these wave latencies of the diabetes mellitus group were prolonged compared with the control group. A significant decrease was also found in distortion product otoacoustic emission amplitudes at 4, 6, 8, and 10 kHz in the high blood glucose and diabetes mellitus groups compared to the control group. There was a significant increase in thiobarbituric acid reactive substances values due to the increase in blood glucose levels in the high blood glucose and diabetes mellitus groups compared to the control group. Conclusion: These results suggested that high blood glucose levels may cause hearing impairment not only in the diabetic state but also in the period of hyperglycemia before the onset of manifest diabetes mellitus and reactive oxygen substances may play an important role in the pathophysiology of diabetes mellitus. We suggest that regulating high glucose levels even before the onset of manifest diabetes mellitus may prevent hazardous effects on hearing function. Level of evidence: Level 3.

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Possible correlations between orthorexic self-reports, unhealthy nutritional beliefs, behavioral rigidity related to following rules, and distortion of body self-image were investigated. In total, 246 university students of both sexes, from different areas of knowledge, answered a sociodemographic form, the Ortho-15, the Body Shape Questionnaire, the Rigidity Scale, and a Nutritional Beliefs Form. Orthorexic self-reports were observed in 73 men and 106 women. A positive correlation was found between females and orthorexic self-reports (p = 0.036), and severe distortion of body self-image (p = 0.002) and between the latter, the behavioral rigidity scale (p2 = 0.189; p = 0.001), and female sex (p2 = 0.245; p < 0.000). In the logistic regression, women were 1.83 times more likely to present orthorexic behaviors than men. The creation of prevention and treatment strategies aimed at women is suggested and it recommended that studies investigating whether the presence of orthorexic self-reports is a risk factor for the development of eating disorders are carried out.

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Objective: To determine the circadian influence on sound sensitivity produced by temporal hearing deprivation in healthy normal human subjects. Design: Participants underwent bilateral earplugging before completion of anthropometry, the author's developed questionnaire, the Hamilton Anxiety and Depression Inventory, pure tone audiometry (PTA), stapedial reflex thresholds (SRT), distortion products otoacoustic emissions input/output (DPOAE-I/O), and uncomfortable loudness levels (ULLs). Afterward, the participants were randomly divided into group A, starting at 8:00 a.m. and finishing at 8:00 p.m., and group B, starting at 4:00 p.m. and ending at 4:00 a.m. Serum cortisol levels and audiological test results were obtained at the beginning and end of the session and 24-h free urinary cortisol levels were measured. Study sample: Thirty healthy volunteers. Results: PTA was 2.68 and 3.33 dB HL in groups A and B, respectively, with no statistical difference between them. ULLs were significantly lower in group A compared to group B, with an average of 8.1 dB SPL in group A and 3.3 dB SPL in group B (p < 0.0001). A SRT shift was observed in group A, with no difference in group B, and a night shift in DPOAE-I/O in group B. Conclusions: Reduced loudness tolerance is demonstrated during daytime hearing deprivation in contrast to nighttime; this may be due to increased central gain in the awake cortex.

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The present work proposes to locate harmonic frequencies that distort the fundamental voltage and current waves in electrical systems using the compressed sensing (CS) technique. With the compressed sensing algorithm, data compression is revolutionized, a few samples are taken randomly, a measurement matrix is formed, and according to a linear transformation, the signal is taken from the time domain to the frequency domain in a compressed form. Then, the inverse linear transformation is used to reconstruct the signal with a few sensed samples of an electrical signal. Therefore, to demonstrate the benefits of CS in the detection of harmonics in the electrical network of this work, power quality analyzer equipment (commercial) is used. It measures the current of a nonlinear load and issues its results of harmonic current distortion (THD-I) on its screen and the number of harmonics detected in the network; this equipment acquires the data based on the Shannon-Nyquist theorem taken as a standard of measurement. At the same time, an electronic prototype senses the current signal of the nonlinear load. The prototype takes data from the current signal of the nonlinear load randomly and incoherently, so it takes fewer samples than the power quality analyzer equipment used as a measurement standard. The data taken by the prototype are entered into the Matlab software via USB, and the CS algorithm run and delivers, as a result, the harmonic distortions of the current signal THD-I and the number of harmonics. The results obtained with the compressed sensing algorithm versus the standard measurement equipment are analyzed, the error is calculated, and the number of samples taken by the standard equipment and the prototype, the machine time, and the maximum sampling frequency are analyzed.

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[3+2] cycloadditions of nitroolefins have emerged as a selective and catalyst-free alternative for the synthesis of 1,2,3-triazoles from azides. We describe mechanistic studies into the cycloaddition/rearomatization reaction sequence. DFT calculations revealed a rate-limiting cycloaddition step proceeding via an asynchronous TS with high kinetic selectivity for the 1,5-triazole. Kinetic studies reveal a second-order rate law, and 13 C kinetic isotopic effects at natural abundance were measured with a significant normal effect at the conjugated olefinic centers of 1.0158 and 1.0216 at the α and ß-carbons of ß-nitrostyrene. Distortion/interaction-activation strain and energy decomposition analyses revealed that the major regioisomeric pathway benefits from an earlier and less-distorted TS, while intermolecular interaction terms dominate the preference for 1,5- over 1,4-cycloadducts. In addition, the major regioisomer also has more favorable electrostatic and dispersion terms. Additionally, while static DFT calculations suggest a concerted but highly asynchronous Ei-type HNO2 elimination mechanism, quasiclassical direct-dynamics calculations reveal the existence of a dynamic intermediate.

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The use of controlled power converters has been extended for high power applications, stacking off-the-shelve semiconductors, and allowing the implementation of, among others, AC drives for medium voltages of 2.3 kV to 13.8 kV. For AC drives based on power cells assembled with three-phase diode rectifiers and cascaded H-bridge inverters, a sophisticated input multipulse transformer is required to reduce the grid voltage, provide isolation among the power cells, and compensate for low-frequency current harmonics generated by the diode-based rectifiers. However, this input multipulse transformer is bulky, heavy, and expensive and must be designed according to the number of power cells, not allowing total modularity of the AC drives based on cascade H-bridges. This study proposes and evaluates a control strategy based on a finite control set-model predictive control that emulates the harmonic cancellation performed by an input multipulse transformer in a cascade H-bridge topology. Hence, the proposed method requires conventional input transformers and replaces the three-phase diode rectifiers. As a result, greater modularity than the conventional multicell converter and improved AC overall input current with a THD as low as 2% with a unitary displacement power factor are achieved. In this case, each power cell manages its own DC voltage using a nonlinear control strategy, ensuring stable system operation for passive and regenerative loads. The experimental tests demonstrated the correct performance of the proposed scheme.

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OBJECTIVE: Previous studies have shown that hearing function is also vulnerable to the effects of diabetes mellitus which can be shown by brainstem auditory evoked potential and distortion product otoacoustic emission recordings. This study aimed to investigate the changes of brainstem auditory evoked potential and distortion product otoacoustic emission in hyperglycemia and whether there is a relationship between reactive oxygen substances production and hearing deterioration in the rat model. METHODS: 25 streptozotocin induced diabetic rats were divided into three groups: control, high blood glucose, and diabetes mellitus. Brainstem auditory evoked potential and distortion product otoacoustic emission were recorded, and thiobarbituric acid reactive substances levels were measured in the brainstem tissue. RESULTS: At 8 kHz, the latencies of I, II, III, IV, and V brainstem auditory evoked potential waves in high blood glucose and diabetes mellitus groups were elongated, at 16 kHz, only these wave latencies of the diabetes mellitus group were prolonged compared with the control group. A significant decrease was also found in distortion product otoacoustic emission amplitudes at 4, 6, 8, and 10 kHz in the high blood glucose and diabetes mellitus groups compared to the control group. There was a significant increase in thiobarbituric acid reactive substances values due to the increase in blood glucose levels in the high blood glucose and diabetes mellitus groups compared to the control group. CONCLUSION: These results suggested that high blood glucose levels may cause hearing impairment not only in the diabetic state but also in the period of hyperglycemia before the onset of manifest diabetes mellitus and reactive oxygen substances may play an important role in the pathophysiology of diabetes mellitus. We suggest that regulating high glucose levels even before the onset of manifest diabetes mellitus may prevent hazardous effects on hearing function. LEVEL OF EVIDENCE: Level 3.

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A two-year old mare was referred to the veterinary hospital because of an increase in the volume of the head on the frontal and left side as well as dyspnoea. Radiographic examination showed an osseous radiopaque spherical mass, with a granular aspect, affecting the left frontal, maxillary, and nasal bones. A frontal sinusotomy was performed, and the frontal sinus was found to be totally obliterated by a granular, yellowish, and hard mass containing multiple spicules. Histologically, it was a multilobulated osseous neoplasia diagnosed as a multilobular osseous tumour. Because of poor prognosis, the animal was euthanized. Necropsy showed that the left nasal cavity was totally effaced as were the nasal sinuses and that the nasal turbinate disappeared because of the hard, yellowish, and granular mass measuring 20 × 14 × 14 cm that surrounded the molar teeth and extended to the cribriform plate. This tumour, which was described only once in horses, is more frequently observed in older dogs' skulls, and must be considered as a differential diagnosis in horses with sinonasal diseases.

Uma égua de dois anos de idade foi encaminhada ao Hospital Veterinário devido a um aumento de volume nas regiões frontal e lateral esquerdas da cabeça, associado à dispneia. Exame radiográfico demonstrou a existência de uma massa esférica radiopaca de aspecto granular afetando os ossos frontal, maxilar e nasal esquerdos. Sinusotomia frontal foi realizada e o seio frontal era totalmente obliterado por uma massa amarelada, granular e dura, com múltiplas espículas. Histologicamente, era uma neoplasia óssea multilobulada, diagnosticada como tumor ósseo multilobular. Devido ao prognóstico ruim, a égua foi eutanasiada. Durante a necropsia, observou-se desaparecimento dos turbinados nasais assim como obliteração total da cavidade nasal esquerda e dos seios nasais por uma massa dura, amarelada e granular, de 20x14x14cm, que circundava os dentes molares e estendia-se à placa cribriforme. Esse tumor, que foi descrito apenas uma vez em equinos, é mais frequente no crânio de cães idosos e deve ser considerado como diagnóstico diferencial em equinos com doenças sinonasais.

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Cisplatin is an antineoplastic agent widely used, and no effective treatments capable of preventing cisplatin-induced ototoxicity and neurotoxicity in humans have yet been identified. This study evaluated the effect of the anti-inflammatory annexin A1 (AnxA1)-derived peptide Ac2-26 in a cisplatin-induced ototoxicity model. Wistar rats received intraperitoneal injections of cisplatin (10 mg/kg/day) for 3 days to induce hearing loss, and Ac2-26 (1 mg/kg) was administered 15 min before cisplatin administration. Control animals received an equal volume of saline. Hearing thresholds were measured by distortion product otoacoustic emissions (DPOAE) before and after treatments. Pharmacological treatment with Ac2-26 protected against cisplatin-induced hearing loss, as evidenced by DPOAE results showing similar signal-noise ratios between the control and Ac2-26-treated groups. These otoprotective effects of Ac2-26 were associated with an increased number of ganglion neurons compared with the untreated cisplatin group. Additionally, Ac2-26 treatment produced reduced immunoreactivity on cleaved caspase 3 and phosphorylated ERK levels in the ganglion neurons, compared to the untreated group, supporting the neuroprotective effects of the Ac2-26. Our results suggest that Ac2-26 has a substantial otoprotective effect in this cisplatin-induced ototoxicity model mediated by neuroprotection and the regulation of the ERK pathway.

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The automobile lateral-view mirrors are the most important visual support for driver safety; therefore, it is important they have robust quality control. Typically, the distortion of a lateral-view mirror is measured using the JIS-D-5705 standard; however, this methodology requires an expert person to perform the measurements and calculations manually, which can induce measurement errors. In this work, a semi-automatic distortion calculation method based on image processing is presented. Distortion calculations of five commercial mirrors from different manufacturers were performed, and a comparative study was carried out between the JIS-D-5705 standard and the proposed method. Experimental results performed according to the JIS-D-5705 standard showed that all mirrors have a distortion lower than 5%, indicating that all meet the standard. On the other hand, the proposed method was able to detect that one of the mirrors presented an important distortion, which was not detected by the methodology proposed in the standard; therefore, that mirror should not meet the standard. Then, it was possible to conclude that the proposed distortion calculation method, based on image processing, has higher robustness and precision than the standard. In addition, an appropriate and effective behavior against changes in scale, resolution, and, unlike the standard, against changes in image rotation was also shown.

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BACKGROUND: According to the European Reference Organization for Quality Assurance Breast Screening and European Diagnostic Services, the spatial accuracy of reconstructed images and reconstruction artifacts must be evaluated in digital breast tomosynthesis (DBT) quality control procedures. PURPOSE: To propose a computational algorithm to evaluate the geometric distortion and artifact spreading (GDAS) in DBT images. MATERIAL AND METHODS: The proposed algorithm analyzed tomosynthesis images of a phantom that contains aluminum spheres (1 mm in diameter) arranged in a rectangular matrix spaced 5 cm apart that was inserted in 5-mm-thick polymethylmethacrylate (PMMA). RESULTS: The obtained results were compared with the values provided by the algorithm developed by the National Coordinating Center for the Physics of Mammography (NCCPM). In the comparison, the results depended on the dimensions of the region of interest (ROI). This dependence proves the benefit of the proposed algorithm because it allows the user to select the ROI. CONCLUSION: The computational algorithm proved to be useful for the evaluation of GDAS in DBT images, in the same way as the reference algorithm (NCCPM), as well as allowing the selection of the ROI dimensions that best suit the spreading of the artifact in the analyzed images.

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Heuristic rules that allow identifying the preferred mixed-valence isomers and Jahn-Teller axis arrangements in the water oxidation catalyst [(Mn4 O4 )(V4 O13 )(OAc)3 ]n- and its activated form [(Mn4 O4 )(V4 O13 )(OAc)2 (H2 O)(OH)]n- are derived. These rules are based on computing all combinatorially possible mixed-valence isomers and Jahn-Teller axis arrangements of the MnIII atoms, and associate energetic costs with some structural features, like crossings of multiple Jahn-Teller axes, the location of these axes, or the involved ligands. It is found that the different oxidation states localize on different Mn centers, giving rise to clear Jahn-Teller distortions, unlike in previous crystallographic findings where an apparent valence delocalization was found. The low barriers that connect different Jahn-Teller axis arrangements suggest that the system quickly interconverts between them, leading to the observation of averaged bond lengths in the crystal structure. We conclude that the combination of cubane-vanadate bonds that are chemically inert, cubane-acetate/water bonds that can be activated through a Jahn-Teller axis, and low activation barriers for intramolecular rearrangement of the Jahn-Teller axes plays an essential role in the reactivity of this and probably related compounds.

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BACKGROUND: Ballet dancers are a risk group for body image (BI) distortion, dissatisfaction and eating disorders (ED), but few studies have investigated these aspects in amateur adult practitioners. This study aimed to evaluate if amateur female adult classical ballet dancers presented different BI and behaviors for ED than gym users and sedentary women. METHODS: This is a cross-sectional study where classical ballet dancers (n = 19) were compared to gym users (n = 19) and sedentary women (n = 19). Body mass index (BMI) was assessed, and a figure rating scale was applied to assess BI distortion/dissatisfaction. The body shape questionnaire (BSQ) was used to measure BI concern. The eating attitudes test (EAT-26) and the bulimic investigatory test, Edinburgh (BITE) were used for behaviors toward anorexia and bulimia. RESULTS: BMI was significantly lower in ballet dancers than gym users and sedentary women (F, p = .04). BI distortion did not differ among the studied groups. BI dissatisfaction was lower (X2, p = .041) in ballet dancers (75.0%) and gym users (70.6%) compared to sedentary women (100%). Correspondence analysis showed ballet dancers were mostly not concerned with BI, which was not observed among the other groups. The EAT-26 did not differ between the studied groups. The BITE score was lower (Tukey's post hoc test, p = .005) in the ballet dancers [mean 5.3 (5.6)] compared to the sedentary women [mean 10.9 (4.8)]. CONCLUSIONS: Data suggest that amateur classical ballet practicing is associated to better BI and fewer behaviors for ED in the studied population. The lower BMI in ballet dancers might explain these findings, and further studies should explore these associations.