Analysis and evaluation of corrosion in naval steels

The corrosion of steel due to seawater is a problem faced by all ships. In this work it has been analyzed two of the variables that most infuence the degradation process of carbon steels in marine environments (pH and chloride concentration), as well as the galvanic couple, which arises when two metals of diferent potential make contact. The study was carried out with two types of steel (S275JR and S235JR) and 15 diferent environments were analyzed (Fig. 1). The progression of corrosion was evaluated in two ways: i) by measuring the mass variation due to the corrosion phenomenon, which was subsequently used to determine the kinetics of the reaction, and ii) visually, by using free software ImageJ. The combined efect of the three variables was analyzed using the Statistics software, performing a factorial analysis in order to obtain response surfaces and their corresponding predictive equations, which allow predicting the efect of corrosion. Finally, in order to observe the diferences between the model obtained and the degree of actual corrosion, both steel types were subjected to the efect of seawater from the dock of the Naval Academy. Results of the study showed a loss of 0,1 g a week, infuenced by the chloride concentration and the acid environment (Fig. 2). From the data obtained, predictive equations were formulated and compared with experiments in laboratory. After 3 weeks of corrosion induced in laboratory, a deviation of 6,74% between the real and predicted mass of probes was observed for steel S275JR and 1,35% for steel S235JR, which evidence the accuracy of the experiments carried out and gives a valuable tool in order to predict efects of corrosion. Corrosion kinetics showed a degradation of 0,3 mm/year and predictive equations showed a deviation lower than 7% in both steels when compared with experiments in laboratory.Peer Reviewe

Conducta asertiva en adolescentes de una institución educativa del Centro Poblado de Cambio Puente ? Chimbote, 2018

El presente trabajo de investigación tuvo como objetivo determinar los niveles de la conducta asertiva que presentan los adolescentes de una institución educativa del centro poblado de Cambio Puente. El estudio correspondió a una investigación descriptiva, básica, cuantitativa; con diseño no experimental y transversal. La población estuvo conformada por 248 adolescentes, varones y mujeres del nivel secundario, entre las edades de 12 a 17 años y matriculados en el periodo académico 2019. Los datos se recolectaron a través del auto-informe de la conducta asertiva ADCA- 1 de García y Mágaz (1992), adaptada al Perú por García (2017).Los resultados encontrados fueron que los adolescentes obtuvieron mayor puntaje en el nivel medio de auto-asertividad (50%) y heteroasertidivdad (48%), con respecto al estilo cognitivo más utilizado por los estudiantes fue el estilo cognitivo asertivo. Los resultados según sexo para autoasertividad corresponden para varones 25.4 % y mujeres 25 % ubicándose en el nivel medio; en hetero-asertividad varones 25.4 y mujeres 22.6% también en el nivel medio y finalmente el estilo cognitivo según sexo es para varones estilo cognitivo asertivo al igual que para las mujeres.Tesi

Microservices and Machine Learning Algorithms for Adaptive Green Buildings

In recent years, the use of services for Open Systems development has consolidated and strengthened. Advances in the Service Science and Engineering (SSE) community, promoted by the reinforcement of Web Services and Semantic Web technologies and the presence of new Cloud computing techniques, such as the proliferation of microservices solutions, have allowed software architects to experiment and develop new ways of building open and adaptable computer systems at runtime. Home automation, intelligent buildings, robotics, graphical user interfaces are some of the social atmosphere environments suitable in which to apply certain innovative trends. This paper presents a schema for the adaptation of Dynamic Computer Systems (DCS) using interdisciplinary techniques on model-driven engineering, service engineering and soft computing. The proposal manages an orchestrated microservices schema for adapting component-based software architectural systems at runtime. This schema has been developed as a three-layer adaptive transformation process that is supported on a rule-based decision-making service implemented by means of Machine Learning (ML) algorithms. The experimental development was implemented in the Solar Energy Research Center (CIESOL) applying the proposed microservices schema for adapting home architectural atmosphere systems on Green Buildings

Clima institucional y satisfacción laboral en los docentes de dos instituciones educativas del distrito de Villa María del Triunfo UGEL 01 - 2014

El propósito general de la investigación fue: Determinar la relación existente entre el clima institucional y satisfacción laboral en docentes de dos instituciones educativas de Villa María del Triunfo, UGEL 01, 2014. Este estudio fue de tipo correlacional por cuanto determinó el grado de relación existente entre las dos variables: clima institucional y satisfacción laboral. El diseño fue no experimental, de corte transversal porque la recolección de datos se realizó en un solo momento. Los datos estadísticos que sostienen esta investigación se han obtenido de los cuestionarios de Clima Institucional y Satisfacción laboral aplicados a docentes. De la prueba estadística de correlación se aprecia que el valor p=0.104 mayor que 0.05, con lo cual se acepta la hipótesis nula y se rechaza la hipótesis alterna, es decir, indica que la relación entre el Clima institucional y la Satisfacción laboral es prácticamente nula, pues no se relacionan significativamente

Cognitive impairment in patients with multiple sclerosis

La esclerosis múltiple es una enfermedad inflamatoria, autoinmune y neurodegenerativa del sistema nervioso central caracterizada por pérdida de la función motora y sensitiva; es considerada una de las principales causas de discapacidad en el adulto joven. Recientemente, se le ha dado gran importancia al deterioro cognitivo, por ser un síntoma frecuente y discapacitante. Este deterioro está presente en un 40 a 65% de los pacientes y afecta la velocidad de procesamiento de información, atención compleja, memoria de trabajo, memoria visual y verbal, fluencia verbal y funciones ejecutivas. Se puede presentar en el síndrome radiológico aislado, en el síndrome clínico aislado y en las diferentes fases de la enfermedad; además, es el responsable de la dependencia de algunos pacientes y de las dificultades para mantener o conseguir empleo. Este déficit cognitivo se asocia a atrofia del tálamo y se ha observado una correlación con las medidas de atrofia y con el volumen lesional cerebral. Existen diferentes herramientas para su evaluación; hay pruebas de cribado breves de 5 minutos de duración, hasta baterías extensas de 90 minutos. Respecto al tratamiento de las alteraciones cognitivas, no existe un tratamiento farmacológico específico; sin embargo, se considera que los fármacos modificadores de la enfermedad podrían tener una influencia favorable en la función cognitiva por sus efectos en la reducción de la actividad inflamatoria y la atrofia cerebral. En cuanto a la estimulación cognitiva, no existen datos concluyentes por las diferentes técnicas empleadas y las distintas medidas utilizadas para evaluar los resultados de las intervenciones.Multiple sclerosis is an inflammatory, autoimmune and neurodegenerative central nervous system disease characterized by motor and sensitive function loss; it is considered to be one of the principal causes of disability in young adults. Recently, cognitive impairment has gain considerable attention because it is a frequent symptom that causes disability. Cognitive impairment it is present in 40 to 65% of patients and affects speed of information processing, complex attention, working memory, visual and verbal memory, verbal fluency and executive functions. It may be present in radiologically isolated syndrome, clinically isolated syndrome and in the different stages of the disease; it is responsible for patient’s dependence and for the difficulties to maintain or get an employment. Cognitive impairment is associated to thalamic atrophy and a correlation with brain atrophy and cerebral lesional volume has been observed. Different evaluation tools are available, there are 5 minutes short screening tests and comprehensive 90 minutes batteries. Regarding cognitive impairment treatment, there is not a specific pharmacological treatment, nevertheless, disease modifying therapies could have a favorable influence on cognitive function because of their effects in the reduction of inflammatory activity and brain atrophy. There are no conclusive data about the efficacy of cognitive stimulation because of the diverse techniques employed and the different measures used to evaluate the results of the interventions

Cultural validity of cognitive markers for Alzheimer's disease (AD) : evidence for global strategies

Background: Availability of culture-free cognitive tests with marker properties for AD has proved a barrier to global harmonization strategies. The European Neurodegenerative Diseases Working Group suggested that the Short-Term Memory Binding Test (STMBT) and the Free and Cued Selective Reminding Test (FCSRT) are useful tests for the early detection of AD (Costa et al., 2017). Yassuda et al. (2019) showed that STMB is insensitive to age and education among healthy Brazilian adults. Parra et al. (2019) suggested that these tests should enter global strategies to aid the early detection of AD. Evidence is still needed to ascertain that such a validity translates to the assessment of affected individuals from underrepresented populations. The current study aimed to shed new light on such an outstanding question. Methods: We recruited 64 healthy controls (HC), 60 patients with Mild Cognitive Impairment (MCI), and 63 patients with mild AD from [Lima at the regional area health clinics of the “Dirección Regional de Salud (DIRESA)” of the “Gobierno Regional del Callao” between June 2018 and May 2019]. They were all illiterate. We considered Illiterate individuals who (1) attended no school or were enrolled for less than one year and (2) could not read or write (a booklet was given which showed a simple sentence). We assessed them with the STMBT, the visual FCSRT, and a brief clinical-neuropsychological protocol. Results: The assessment confirmed the healthy (CDR=0.0, pFAQ=2.2, BDI=5.9), MCI (CDR=0.5, pFAQ=3.7, BDI=6.2), and dementia (CDR=1.3, pFAQ=16.5, BDI=7.2) status of our groups. Significant between-group differences were found with both the STMBT (F(2,184)=590.1, p>>MCI>>>AD. ROC analysis with STMB revealed AUC=0.98 for HC vs. MCI, AUC=1.00 for HC vs. AD, and AUC=0.97 for MCI vs. AD. For the visual FCSRT, an AUC=1.00 was found for HC vs (MCI & AD), and AUC=0.99 for MCI vs AD. Conclusion: The two cognitive markers recently recommended for harmonisation of neuropsychological assessment in neurodegenerative dementias in Europe seem suitable to support such practices in illiterate populations. Parra et al. (2019) recently suggested that only global strategies will help meet global challenges. Here we provide evidence of cognitive markers for AD that can reliably enter such strategies

Evolución histórica del concepto y criterios actuales para el diagnóstico de demencia.

A mediados del siglo XIX se empezó a enfocar el concepto de Demencia, como una entidad irreversible asociada a la edad, Esquirol fue uno de los primeros en plantear una aproximación descriptiva del cuadro clínico, y Bayle el primero en proponer Demencia como una enfermedad atribuible a lesiones en el sistema nervioso central. Fue alrededor del año 1900, que Alois Alzheimer precisó las lesiones patológicas de dos entidades clínicas distintas, la primera descrita por él mismo, y la segunda por Arnold Pick (conocidas hoy como enfermedad de Alzheimer y demencia frontotemporal respectivamente). Conforme progresaron las técnicas de imágenes cerebrales y estudios de líquido cefalo-raquídeo fueron mejorando los criterios de diagnóstico para los diversos tipos de demencia, con un enfoque clínico-biológico. Las recomendaciones más recientes, sin embargo proponen un enfoque exclusivamente biológico de la enfermedad de Alzheimer

Phylogenetic analysis of secondary metabolites in a plant community provides evidence for trade-offs between biotic and abiotic stress tolerance

Plants' responses to conflicting stresses may result in physiological trade-offs due to the inter-dependent and costly nature of physiological investments. Physiological tradeoffs have been proved within species, but to what extent these trade-offs are the result of phylogenetic constraints remains poorly known. Environmental stresses can vary widely in different biomes, and therefore assessing physiological tradeoffs across species must account for this variation. One way of doing so is to assess it within a community, where the co-occurring species have faced a shared combination of filters to establish. Considering a representative sample of species in a single community, we use a macroevolutionary approach to test the hypothesis that plant physiological trade-offs are evolutionarily conserved within this community (i.e., closely-related species tend to solve the trade-offs similarly). We analyze the content of five metabolites in thirty co-occurring plant species, capturing their range of contrasting exposures to abiotic and biotic stresses (growing solitary and in vegetation patches). Our results support that species investment in response to abiotic stress (i.e., proline and abscisic acid content) is traded off against their investment to face biotic stress (i.e., jasmonic acid and salicylic acid), shown by the contrasting loadings of these two groups of metabolites in the first axes of a principal component analysis (PCA). In addition, the metabolic strategies observed in this community are evolutionarily conserved, as closely related species tend to have similar scores in this PCA, and thus resemble each other in their balance. This is shown by a significant phylogenetic signal in the species’ scores along the first axes of the PCA. Incorporating the evolutionary history of plant species into physiological studies can help to understand the response of plants to multiple stresses currently acting in ecological communities

Extensive brain calcification and chorea in probable post surgical hypoparathyroidism

Introducción: Las calcificaciones cerebrales pueden ser unilaterales o bilaterales; las unilaterales presentan como etiología las infecciones, infartos o traumatismos; las bilaterales pueden ser fisiológicas, metabólicas o idiopáticas. Caso clínico: Paciente mujer, de 48 años de edad, tiroidectomizada hace 27 años, tomaba levotiroxina; acudió por movimientos involuntarios coreicos y balísticos progresivos y dificultad para caminar. Se encontró hipotonía de hemicuerpo derecho y movimientos serpenteantes de miembro superior derecho, hipocalcemia, hiperfosfatemia y concentración baja de parathormona; la tomografia y resonancia magnética cerebrales evidenciaban calcificaciones bilaterales en ganglios basales y cerebelo. Recibió tratamiento con citrato de calcio, calcitriol y risperidona, con recuperación completa. Discusión: Los pacientes con calcificaciones de ganglios basales presentan síntomas extrapiramidales (20 a 30%), como parkinsonismo o coreoatetosis, convulsiones y trastornos neuropsiquiátricos. Las calcificaciones intracerebrales bilaterales se producen generalmente por depósito de calcio y otros minerales. El hipoparatiroidismo es una complicación frecuente en la tiroidectomía radical, con hipocalcemia, hiperfosfatemia y concentración baja de parathormona como el caso descrito. Algunos pacientes no desarrollan los síntomas de inmediato. El tratamiento mejora los síntomas sin alterar las calcificaciones, como en la paciente, en quien la mejoría sería por la normalización del calcio más que por la risperidona.Introduction: Cerebral calcifications may be unilateral or bilateral; unilateral etiology may include infections, trauma or stroke and bilateral may be physiologic, metabolic or idiopathic. Case report: Female 48 year-old patient who had thyroidectomy 27 years before, received levothyroxine, and who was attended for chorea, ballistic involuntary movements and progressive difficulty in walking. She presented right sided hypotonia, right upper limb winding movements, hypocalcemia, hyperphosphatemia and low parathormone levels; tomography and magnetic resonance showed bilateral calcifications in brain basal ganglia and cerebellum. She was treated with calcium citrate, calcitriol and risperidone with complete recovery. Discussion: Patients with basal ganglia calcifications have extrapyramidal symptoms (20-30%) such as parkinsonism or coreoatetosis, seizures, and neuropsychiatric disorders. Brain bilateral calcifications usually consist in calcium and other minerals deposit. Hypoparathyroidism is frequent complication of radical thyroidectomy accompanied with hypocalcemia, hyperphosphatemia and parathormone low concentration as the case described. Some patients do not develop symptoms immediately. Treatment improves symptoms but not calcifications; in our patient improvement would be due to calcium normalization more than risperidone treatment