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PURPOSE: This investigation aimed to explore attribute dynamics and symptomatic comorbidity of depression with internalizing, externalizing, and other personal-contextual problems in children and adolescents from a network analysis. METHODS: We tested an attribute network of regularized partial correlations, standard and alternative centrality measures, and comorbidity bridge symptoms according to centrality bridge measures. RESULTS: Regularized partial correlation network and a centrality measures graph shown the prominent position of social problems and anxiety-depression. Minimum spanning tree (MST) found a hierarchical dynamics between attributes where mixed anxiety-depression was identified as the core and the other attributes were hierarchically connected to it by being positioned in six branches that are differentiated according to their theoretical contents. The most central connections are established with the attributes of their own community or theoretical groups, and 37 bridge symptoms were identified in all networks. CONCLUSIONS: A significant role of mixed anxiety depression as an activator and intermediary of psychopathologies was supported as a central attribute of internalizing problems. Aggressive behavior as part of the broad externalizing dimension was one of the constructs that most intensively activate the network, and social problems were also distinguished as a relevant factor not only in terms of connections and central attributes but also in terms of bridge symptoms and comorbidity. This framework extends to the study of symptomatic "comorbidity."

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The combination of depression and anxiety is among the most prevalent comorbidities of disorders leading to substantial functional impairment in children and adolescents. The network perspective offers a new paradigm for understanding and measuring psychological constructs and their comorbidity. The present study aims to apply network analysis to explore the comorbidity between depression and anxiety symptoms. Specifically, the study examines bridge symptoms, comorbidity, and shortest pathway networks and estimates the impact of the symptoms in the network's connectivity and structure. The findings show that "feeling lonely" and "feeling unloved" are identified as the most central bridge symptoms. The shortest path network suggests that the role of a mixed anxiety-depressive symptomatology, and specific and non-specific symptoms of clinical criteria, such as "worries," "feels depressed," "fears school," and "talks about suicide" could serve as a warning for comorbidity.

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The detection of cracks is an important monitoring task in civil engineering infrastructure devoted to ensuring durability, structural safety, and integrity. It has been traditionally performed by visual inspection, and the measurement of crack width has been manually obtained with a crack-width comparator gauge (CWCG). Unfortunately, this technique is time-consuming, suffers from subjective judgement, and is error-prone due to the difficulty of ensuring a correct spatial measurement as the CWCG may not be correctly positioned in accordance with the crack orientation. Although algorithms for automatic crack detection have been developed, most of them have specifically focused on solving the segmentation problem through Deep Learning techniques failing to address the underlying problem: crack width evaluation, which is critical for the assessment of civil structures. This paper proposes a novel automated method for surface cracking width measurement based on digital image processing techniques. Our proposal consists of three stages: anisotropic smoothing, segmentation, and stabilized central points by k-means adjustment and allows the characterization of both crack width and curvature-related orientation. The method is validated by assessing the surface cracking of fiber-reinforced earthen construction materials. The preliminary results show that the proposal is robust, efficient, and highly accurate at estimating crack width in digital images. The method effectively discards false cracks and detects real ones as small as 0.15 mm width regardless of the lighting conditions.

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This paper reports on the progress of a wearable assistive technology (AT) device designed to enhance the independent, safe, and efficient mobility of blind and visually impaired pedestrians in outdoor environments. Such device exploits the smartphone's positioning and computing capabilities to locate and guide users along urban settings. The necessary navigation instructions to reach a destination are encoded as vibrating patterns which are conveyed to the user via a foot-placed tactile interface. To determine the performance of the proposed AT device, two user experiments were conducted. The first one requested a group of 20 voluntary normally sighted subjects to recognize the feedback provided by the tactile-foot interface. The results showed recognition rates over 93%. The second experiment involved two blind voluntary subjects which were assisted to find target destinations along public urban pathways. Results show that the subjects successfully accomplished the task and suggest that blind and visually impaired pedestrians might find the AT device and its concept approach useful, friendly, fast to master, and easy to use.

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The CO2 and water vapor exchange between leaf and atmosphere are relevant for plant physiology. This process is done through the stomata. These structures are fundamental in the study of plants since their properties are linked to the evolutionary process of the plant, as well as its environmental and phytohormonal conditions. Stomatal detection is a complex task due to the noise and morphology of the microscopic images. Although in recent years segmentation algorithms have been developed that automate this process, they all use techniques that explore chromatic characteristics. This research explores a unique feature in plants, which corresponds to the stomatal spatial distribution within the leaf structure. Unlike segmentation techniques based on deep learning tools, we emphasize the search for an optimal threshold level, so that a high percentage of stomata can be detected, independent of the size and shape of the stomata. This last feature has not been reported in the literature, except for those results of geometric structure formation in the salt formation and other biological formations.

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BACKGROUND: Medical knowledge is accumulated in scientific research papers along time. In order to exploit this knowledge by automated systems, there is a growing interest in developing text mining methodologies to extract, structure, and analyze in the shortest time possible the knowledge encoded in the large volume of medical literature. In this paper, we use the Latent Dirichlet Allocation approach to analyze the correlation between funding efforts and actually published research results in order to provide the policy makers with a systematic and rigorous tool to assess the efficiency of funding programs in the medical area. RESULTS: We have tested our methodology in the Revista Médica de Chile, years 2012-2015. 50 relevant semantic topics were identified within 643 medical scientific research papers. Relationships between the identified semantic topics were uncovered using visualization methods. We have also been able to analyze the funding patterns of scientific research underlying these publications. We found that only 29% of the publications declare funding sources, and we identified five topic clusters that concentrate 86% of the declared funds. CONCLUSIONS: Our methodology allows analyzing and interpreting the current state of medical research at a national level. The funding source analysis may be useful at the policy making level in order to assess the impact of actual funding policies, and to design new policies.

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Stress is a widespread problem in today's societies, having important consequences on brain function. Among the plethora of mechanisms involved in the stress response at the molecular level, the role of microRNAs (miRNAs) is beginning to be recognized. The control of gene expression by these noncoding RNAs makes them essential regulators of neuronal and synaptic physiology, and alterations in their levels have been associated with pathological conditions and mental disorders. In particular, the excitatory (i.e., glutamate-mediated) neurotransmission is importantly affected by stress. Here, we found that loss of miR-26a-5p (miR-26a henceforth) function in primary hippocampal neurons increased the frequency and amplitude of miniature excitatory currents, as well as the expression levels of the excitatory postsynaptic scaffolding protein PSD95. Incubation of primary hippocampal neurons with corticosterone downregulated miR-26a, an effect that mirrored our in vivo results, as miR-26a was downregulated in the hippocampus as well as in blood serum-derived small extracellular vesicles (sEVs) of rats exposed to two different stress paradigms by movement restriction (i.e., stress by restraint in cages or by complete immobilization in bags). Overall, these results suggest that miR-26a may be involved in the generalized stress response and that a stress-induced downregulation of miR-26a could have long-term effects on glutamate neurotransmission.

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Horizontal displacements of a multiple-anchor pile wall in a 28.5 m deep excavation using the top-down construction method have been monitored using optical fiber (Brillouin optical time-domain reflectometry (BOTDR)), strain gauges, inclinometers, and a topographic survey. This work presents a comparison between these different techniques to measure horizontal displacements in the pile at several stages of the soil excavation process. It was observed that displacements can be separated into two components: Rigid body motion and pile flexural deformation. Measurements using optical fiber and inclinometers are considered the most adequate and easy to install. A numerical model allows us to evaluate the influence of earth pressure on the estimated horizontal displacements. It is shown that using soil pressure on the wall given by p = 0.65Kaγh, on a simplified modeled wall, provides a close deduction of horizontal displacements compared to observed values on the field.

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Segmentation is one of the most important stages in the 3D reconstruction of macromolecule structures in cryo-electron microscopy. Due to the variability of macromolecules and the low signal-to-noise ratio of the structures present, there is no generally satisfactory solution to this process. This work proposes a new unsupervised particle picking and segmentation algorithm based on the composition of two well-known image filters: Anisotropic (Perona-Malik) diffusion and non-negative matrix factorization. This study focused on keyhole limpet hemocyanin (KLH) macromolecules which offer both a top view and a side view. Our proposal was able to detect both types of views and separate them automatically. In our experiments, we used 30 images from the KLH dataset of 680 positive classified regions. The true positive rate was 95.1% for top views and 77.8% for side views. The false negative rate was 14.3%. Although the false positive rate was high at 21.8%, it can be lowered with a supervised classification technique.

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This study assessed the intra-individual reliability of oxygen saturation in intercostal muscles (SmO2-m.intercostales) during an incremental maximal treadmill exercise by using portable NIRS devices in a test-retest study. Fifteen marathon runners (age, 24.9 ± 2.0 years; body mass index, 21.6 ± 2.3 kg·m-2; V̇O2-peak, 63.7 ± 5.9 mL·kg-1·min-1) were tested on two separate days, with a 7-day interval between the two measurements. Oxygen consumption (V̇O2) was assessed using the breath-by-breath method during the V̇O2-test, while SmO2 was determined using a portable commercial device, based in the near-infrared spectroscopy (NIRS) principle. The minute ventilation (VE), respiratory rate (RR), and tidal volume (Vt) were also monitored during the cardiopulmonary exercise test. For the SmO2-m.intercostales, the intraclass correlation coefficient (ICC) at rest, first (VT1) and second ventilatory (VT2) thresholds, and maximal stages were 0.90, 0.84, 0.92, and 0.93, respectively; the confidence intervals ranged from -10.8% - +9.5% to -15.3% - +12.5%. The reliability was good at low intensity (rest and VT1) and excellent at high intensity (VT2 and max). The Spearman correlation test revealed (p ≤ 0.001) an inverse association of SmO2-m.intercostales with V̇O2 (ρ = -0.64), VE (ρ = -0.73), RR (ρ = -0.70), and Vt (ρ = -0.63). The relationship with the ventilatory variables showed that increased breathing effort during exercise could be registered adequately using a NIRS portable device.

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Advances in eye-tracking technology have led to better human-computer interaction, and involve controlling a computer without any kind of physical contact. This research describes the transformation of a commercial eye-tracker for use as an alternative peripheral device in human-computer interactions, implementing a pointer that only needs the eye movements of a user facing a computer screen, thus replacing the need to control the software by hand movements. The experiment was performed with 30 test individuals who used the prototype with a set of educational videogames. The results show that, although most of the test subjects would prefer a mouse to control the pointer, the prototype tested has an empirical precision similar to that of the mouse, either when trying to control its movements or when attempting to click on a point of the screen.

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La comorbilidad entre depresión y agresión infanto-adolescente ha sido contrastada básicamente a un nivel estadístico. Sin embargo, pocos estudios han comprobado de manera longitudinal otra de las premisas fundamentales que permite establecer la comorbilidad: la sinergia, es decir, la acción conjunta de dos o más trastornos que se traduce en una severidad y cronicidad superior a las generadas por la suma de los efectos individuales. Mediante un diseño longitudinal a lo largo de 3 años se examinó la severidad y cronicidad de un grupo de sujetos comórbidos depresivos - agresivos. Se analizaron los niveles de depresión y agresión, así como el papel del sexo en estas relaciones. La evaluación se realizó a través de autoinformes en una muestra de 525 sujetos de edades comprendidas entre los 11 y 13 años. La muestra fue aleatoriamente seleccionada de diferentes colegios de la Comunidad de Madrid (España). Los resultados muestran que la depresión y agresión se relacionan de manera estadísticamente significativa. Los sujetos comórbidos exhiben una cronicidad de mayor duración en las respuestas agresivas que en las depresivas. La severidad en los sujetos comórbidos es mayor en las respuestas agresivas de tipo total y verbal, así como en las depresivas. El sexo no ejerce ningún efecto significativo. Se concluye que los datos indican la importancia de explorar la comorbilidad con diferentes tipos de agresión, especialmente la verbal, y en diferentes grupos de edad. Se discute la necesidad de atender a los síntomas subyacentes al trastorno principal en afectados de larga duración, ya que a la expresión de uno de los trastornos puede subyacer la cronicidad asociada a la comorbilidad con importantes repercusiones para su diagnóstico y tratamiento.(AU)

The comorbidity between depression and aggression in children and adolescents is an issue that has sparked controversy as its existence has important implications for the validity of the classification systems, for the establishment of explanatory models, the design of new treatments as well as in the final outcome which the comorbid person presents in these in comparison with conventional treatments. In addition, the prevalence rates in depressive-aggressive comorbidity are significant, oscillating between 7.97 and 10.91%. Therefore, the study of comorbidity becomes necessary and the lack of studies focusing on the subject comes as a surprise. Perhaps one of the main problems concerning the research of comorbidity lies in the fact that most of the studies do not validate the clinical criteria that focuses on the principle of synergy, as Clark and Watson had established in Tripartite model, since doing so would require longitudinal studies measuring the effects of a commorbid disorder in contrast to those where there is no comorbidity to be found. In addition to clinical judgment, the Tripartite model demands a further statistic indicating the existence of a significant correlation between those synergistic disorders, which is the one on which most studies have been focusing. This type of results, based solely on clinical judgment, mainly through cross-sectional studies, has not allowed to implement another type of results, as suggested by the Tripartite model, that would have helped to establish clinical and diagnostic criteria through dimensional self-assessment tools which are closer to a reality in child and adolescent assessment where comorbidity is rather the rule than the exception. Therefore, that kind of study, using a longitudinal design over a period of three years, will help expand those cross-sectional ones, which will allow for examining whether there is a significant association, as well as a synergy that attests to the existence of an aggressive-depressive comorbidity on both, statistical and clinical level. In order to do so this study examined the severity and chronicity of a group of comorbid depressive-aggressive persons. In addition, the levels of depression and aggression and the role of sex within these relationships were analyzed. The sample, randomly selected from different schools in the Community of Madrid (Spain), comprised 525 individuals ranging from 11 to 13 years old, 58.9% female, the family structure was mostly biparental (92%) and the vast majority belonged to a middle class environment (85%). Depression and aggression were assessed through specific types of self-report questionnaires for children and adolescents, both in their Spanish version. The results support the statistical basis, since depression and aggression exhibit a significant positive and moderate association ranging between .11 and .24, in which the fact that the found association was higher within verbal aggression than in the physical one among all ages with the exception of the group of subjects to testing aged 12 needs to be stressed. With regards to the clinical criteria, the results provide partial support, as comorbid subjects exhibit a longer duration in chronic aggressive symptoms than those other groups affected only by depression or aggression, while they are similar to those of merely depressive subjects in the symptoms indicating a depression. Regarding severity, comorbid subjects show a higher level within the field of totally and verbally aggressive symptoms, as well as in the depressive ones which makes their physical aggression comparable to the one found in the test group of total aggression, hence, the data partially support the clinical standard. The tested persons sex, however, is of no significant meaning for the outcome. In conclusion, the data indicates the importance of exploring the comorbidity of different types of aggression, particularly the verbal one, and within different age groups. The need for addressing the underlying primary disorder symptoms in long-term affected patients is discussed, since chronic comorbidity may underlie the expression of one of the disorders and entail important implications for diagnosis and treatment.(AU)

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La comorbilidad entre depresión y agresión infanto-adolescente ha sido contrastada básicamente a un nivel estadístico. Sin embargo, pocos estudios han comprobado de manera longitudinal otra de las premisas fundamentales que permite establecer la comorbilidad: la sinergia, es decir, la acción conjunta de dos o más trastornos que se traduce en una severidad y cronicidad superior a las generadas por la suma de los efectos individuales. Mediante un diseño longitudinal a lo largo de 3 años se examinó la severidad y cronicidad de un grupo de sujetos comórbidos depresivos - agresivos. Se analizaron los niveles de depresión y agresión, así como el papel del sexo en estas relaciones. La evaluación se realizó a través de autoinformes en una muestra de 525 sujetos de edades comprendidas entre los 11 y 13 años. La muestra fue aleatoriamente seleccionada de diferentes colegios de la Comunidad de Madrid (España). Los resultados muestran que la depresión y agresión se relacionan de manera estadísticamente significativa. Los sujetos comórbidos exhiben una cronicidad de mayor duración en las respuestas agresivas que en las depresivas. La severidad en los sujetos comórbidos es mayor en las respuestas agresivas de tipo total y verbal, así como en las depresivas. El sexo no ejerce ningún efecto significativo. Se concluye que los datos indican la importancia de explorar la comorbilidad con diferentes tipos de agresión, especialmente la verbal, y en diferentes grupos de edad. Se discute la necesidad de atender a los síntomas subyacentes al trastorno principal en afectados de larga duración, ya que a la expresión de uno de los trastornos puede subyacer la cronicidad asociada a la comorbilidad con importantes repercusiones para su diagnóstico y tratamiento.

The comorbidity between depression and aggression in children and adolescents is an issue that has sparked controversy as its existence has important implications for the validity of the classification systems, for the establishment of explanatory models, the design of new treatments as well as in the final outcome which the comorbid person presents in these in comparison with conventional treatments. In addition, the prevalence rates in depressive-aggressive comorbidity are significant, oscillating between 7.97 and 10.91%. Therefore, the study of comorbidity becomes necessary and the lack of studies focusing on the subject comes as a surprise. Perhaps one of the main problems concerning the research of comorbidity lies in the fact that most of the studies do not validate the clinical criteria that focuses on the principle of synergy, as Clark and Watson had established in Tripartite model, since doing so would require longitudinal studies measuring the effects of a commorbid disorder in contrast to those where there is no comorbidity to be found. In addition to clinical judgment, the Tripartite model demands a further statistic indicating the existence of a significant correlation between those synergistic disorders, which is the one on which most studies have been focusing. This type of results, based solely on clinical judgment, mainly through cross-sectional studies, has not allowed to implement another type of results, as suggested by the Tripartite model, that would have helped to establish clinical and diagnostic criteria through dimensional self-assessment tools which are closer to a reality in child and adolescent assessment where comorbidity is rather the rule than the exception. Therefore, that kind of study, using a longitudinal design over a period of three years, will help expand those cross-sectional ones, which will allow for examining whether there is a significant association, as well as a synergy that attests to the existence of an aggressive-depressive comorbidity on both, statistical and clinical level. In order to do so this study examined the severity and chronicity of a group of comorbid depressive-aggressive persons. In addition, the levels of depression and aggression and the role of sex within these relationships were analyzed. The sample, randomly selected from different schools in the Community of Madrid (Spain), comprised 525 individuals ranging from 11 to 13 years old, 58.9% female, the family structure was mostly biparental (92%) and the vast majority belonged to a middle class environment (85%). Depression and aggression were assessed through specific types of self-report questionnaires for children and adolescents, both in their Spanish version. The results support the statistical basis, since depression and aggression exhibit a significant positive and moderate association ranging between .11 and .24, in which the fact that the found association was higher within verbal aggression than in the physical one among all ages with the exception of the group of subjects to testing aged 12 needs to be stressed. With regards to the clinical criteria, the results provide partial support, as comorbid subjects exhibit a longer duration in chronic aggressive symptoms than those other groups affected only by depression or aggression, while they are similar to those of merely depressive subjects in the symptoms indicating a depression. Regarding severity, comorbid subjects show a higher level within the field of totally and verbally aggressive symptoms, as well as in the depressive ones which makes their physical aggression comparable to the one found in the test group of total aggression, hence, the data partially support the clinical standard. The tested person's sex, however, is of no significant meaning for the outcome. In conclusion, the data indicates the importance of exploring the comorbidity of different types of aggression, particularly the verbal one, and within different age groups. The need for addressing the underlying primary disorder symptoms in long-term affected patients is discussed, since chronic comorbidity may underlie the expression of one of the disorders and entail important implications for diagnosis and treatment.

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PURPOSE: To determine the incidence and morphologic characteristics of knee chondral lesions found at arthroscopy and their correlation with magnetic resonance imaging (MRI). METHODS: This is a prospective study on 190 consecutive knee arthroscopic procedures performed between March 2003 and February 2004 by the same surgical team. The study group's age average was 34.8 years (14 to 77 years). The indication for surgery included anterior cruciate ligament tears, meniscal tears, and anterior knee pain. Patients without a preoperative MRI study were excluded. MRI reports were performed by qualified radiologists in all the cases. Chondral lesions were classified according to the International Cartilage Repair Society (ICRS) classification and were included in a database along with the MRI reports. The results were analyzed statistically with analysis of variance, Pearson, kappa, and chi-square tests. RESULTS: One hundred fifteen chondral lesions in 82 patients were found during the arthroscopic procedure. Most of them were single lesions (72%) located on the medial femoral condyle (32.2%) or medial patellae (22.6%); 62.6% of the lesions were classified as ICRS type 2 or 3-A, with an average surface of 1.99 cm2. We found a significant direct correlation between the patient's age and the size of the lesion (P = .001). MRI sensitivity was 45% with a specificity of 100%. The sensitivity increased with deeper lesions (direct relation with the ICRS classification). Our results showed a statistical power of 100%. CONCLUSIONS: Although unenhanced MRI using a 1.5-Tesla magnet with conventional sequences (proton density-weighted, T1-weighted, and T2-weighted) is most accurate at revealing deeper lesions and defects at the patellae, our study shows that a considerable number of lesions will remain undetected until arthroscopy, which remains the gold standard. LEVEL OF EVIDENCE: Level III, diagnostic study of nonconsecutive patients.

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The aim of this study was to determine the prevalence of hepatitis C virus antibodies in high rosk patients coming from Valdivia, Osorno and Puerto Montt. Fiftysix patients in hemodialysis, 51 renal grafts recipients, 42 cirrhotic and 14 patients with acute non A non B hepatitis were studied. Antibodies were detected with a second generation ELISA technique and positive cases were confirmed with RIBA. All hemodialysis patients and renal grafts recipients were negative for hepatitis C virus antibodies. In one non alcoholic patient with cirrhosis, a positive ALISA was confirmed with RIBA. Six patients with acute hepatitis had a positive ALISA tests but none was confirmed with RIBA. It is concluded that the prevalence of hepatitis C virus antibodies in this region of Chile is very low

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En el presente trabajo se realizo un analisis de los elementos sometidos a flexion. Para efectos de torsion y corte no se vio necesario un analisis particular para el Hormigon Parcialmente Pretensado, pudiendose usar los mismos conceptos y formulas desarrolladas para el Hormigon Totalmente Pretensado. El trabajo se divide en dos partes a) Analisis teorico a la flexion para vigas I, que puede ser aplicado en secciones cajon. En el analisis teorico se estudiaron el estado limite ultimo, y el estado bajo cargas de servicio, en este se incluye un analisis de la fisuracion y las de flexiones. Se propone un metodo para diseno de Hormigon Parcialmente Pretensado. b) Programas en computadora que realizan un calculo automatico y permiten optimizar la estructura. Los programas incluyen: un programa para el analisis de cargas en puentes continuos (Envolvente de momentos), un programa para el diseno de vigas en general y un programa que verifica las condiciones de servicio.

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