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Tsunami damage detection with remote sensing: A review
No full textTsunamis are rare events compared with the other natural disasters, but once it happens, it can be extremely devastating to the coastal communities. Extensive inland penetration of tsunamis may cause the difficulties of understanding its impact in the aftermath of its generation. Therefore the social needs to technologies of detecting the wide impact of great tsunamis have been increased. Recent advances of remote sensing and technologies of image analysis meet the above needs and lead to more rapid and efficient understanding of tsunami affected areas. This paper provides a review of how remote sensing methods have developed to contribute to post-tsunami disaster response. The evaluations in the performances of the remote sensing methods are discussed according to the needs of tsunami disaster response with future perspective. ©2020 by the authors. Licensee MDPI, Basel, Switzerland.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
3D elasticity numerical solution for the static behavior of FGM shells
No full textSe presenta una solución numérica para el análisis estático tridimensional de láminas graduadas funcionalmente con curvatura constante. La solución se basa en tres ecuaciones de elasticidad escritas en coordenadas curvilíneas ortogonales que son válidas para paneles de cubierta esféricos, cilíndricos y placas rectangulares. Las ecuaciones en términos de las variables de la superficie media se resuelven mediante una suma de armónicos en términos del método de Navier, que es válido solo para estructuras simplemente apoyadas. Las ecuaciones en función de la dirección del espesor se resuelven numéricamente por el método de Cuadratura Diferencial (DQM) que permitió calcular fácilmente la derivada aproximada de una función utilizando una suma ponderada de las funciones evaluadas en una determinada grilla. Las capas de la estructura se discretizan por separado mediante la cuadrícula de Chebyshev-Gauss-Lobatto y los polinomios de interpolación de Lagrange se consideran como funciones base. La continuidad interlaminar del corte transversal se impone como parte de las condiciones de contorno del método presentado. Las condiciones de contorno de las tensiones fuera del plano en la parte superior e inferior debidas a las cargas aplicadas en la lámina también se consideran para el análisis, como resultado, este método puede predecir el comportamiento correcto de la distribución a través del espesor de las fuerzas transversales. hace hincapié Este método permitió discretizar fácilmente el material en términos de la dirección del espesor y se analizaron varios tipos de estructuras de sándwich y capas individuales graduadas funcionalmente con núcleo graduado funcionalmente. Se analizan varias láminas sometidas a carga distribuida bisinusoidal y uniforme. Los resultados se comparan con otras soluciones tridimensionales propuestas en la literatura y modelos bidimensionales precisos. © 2019Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Histopathology associated with infection by Procamallanus (Spirocamallanus) inopinatus (Nematoda) in farmed Brycon cephalus (Characiformes) from Peru: a potential fish health problem
No full textWe describe the histopathological damage caused by parasite infection in farmed specimens of matrinxã Brycon cephalus, an economic important fish for aquaculture in the Amazon region. The fish were collected from an extensive fish farm, nearby the city of Nauta, Department of Loreto, Peru. Parasitic nematodes were found infecting the small intestine in 73 of 80 specimens (91.25%) of B. cephalus. According to morphological features of the examined specimens using light and electronic microscopy, the nematode was identified as Procamallanus (Spirocamallanus) inopinatus. Histological sections of the small intestine showed important damages on the tissue, such as desquamation, abrasion, compression, hypertrophy, and villi loss as well as necrosis in muscle layer, submucosa, and mucosa. This is the first report of tissue damage occurrences in the concerned host from fish farm in Peruvian Amazon, and it confirms the high pathogenicity of the nematode species and further points out the need of improving the strategies of parasitic prevention and control in order to better prevent future disease outbreaks that compromise production.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
An emerging public health threat: Mayaro virus increases its distribution in Peru
No full textBackground: The infection caused by Mayaro virus (MAYV), which presents as an acute febrile illness, is considered a neglected tropical disease. The virus is an endemic and emerging pathogen in South America and the Caribbean, responsible for occasional and poorly characterized outbreaks. Currently there is limited information about its expansion and risk areas. Methods: A cross-sectional study was performed in 10 urban primary care health centers in the Cajamarca region of Peru from January to June 2017. A total of 359 patients with suspected febrile illness were assessed. RNA was extracted from serum samples, following which MAYV real-time reverse transcriptase PCR (RT-PCR) for the detection of the nsP1 gene was performed. Results: MAYV was detected in 11.1% (40/359) of samples after RT-PCR amplification and confirmatory DNA sequencing. Most infections were detected in the adult population aged 18–39 years (40%) and 40–59 years (32.5%). Headache was the most frequent symptom in patients with MAYV infection (77.5%), followed by fever (72.5%), myalgia (55.0%), and arthralgia (50.0%). During the study, most of the MAYV cases were seen in May (47.5%) and April (35.0%), corresponding to the dry season (months without rain). Conclusions: This study is novel in describing the presence of MAYV in Cajamarca, an Andean region of Peru. Symptoms are non-specific and can be confused with those of other arbovirus or bacterial infections. Molecular biology methods such as RT-PCR allow the timely and accurate detection of MAYV and could thus be considered as a tool for surveillance in endemic areas. © 2020 The Author(s)Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Corruption in health systems: The conversation has started, now time to continue it: Comment on “We need to talk about corruption in health systems”
No full textHolistic and multi-disciplinary responses should be prioritized given the depth and breadth through which corruption in the healthcare sector can cover. Here, taking the Peruvian context as an example, we will reflect on the issue of corruption in health systems, including corruption with roots within and outside the health sector, and ongoing efforts to combat it. Our reflection of why corruption in health systems in settings with individual and systemic corruption should be an issue that is taken more seriously in Peru and beyond aligns with broader global health goals of improving health worldwide. Addressing corruption also serves as a pragmatic approach to health system strengthening and weakens a barrier to achieving universal health coverage and Sustainable Development Goals related to health and justice. Moreover, we will argue that by pushing towards a practice of normalizing the conversation about corruption in health has additional benefits, including expanding the problematization to a wider audience and therefore engaging with communities. For young researchers and global health professionals with interests in improving health systems in the early career stages, corruption in health systems is an issue that could move to the forefront of the list of global health challenges. This is a challenge that is uniquely multi-disciplinary, spanning the health, economy, and legal sectors, with wider societal implications. © 2020 The Author(s).Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Best non-polynomial shear deformation theories for cross-ply single skin and sandwich shells
No full textThis paper presents Best Theory Diagrams (BTDs) constructed from non-polynomial terms to identify best shell theories for bending analysis of cross-ply single skin and sandwich shell panels. This structure presents a constant radii of curvature. The shell theories are constructed using Axiomatic/Asymptotic Method (AAM). The different shell theories are described using the Carrera's Unified Formulation. The governing equations are derived from the Principle of Virtual Displacement (PVD). Navier-Type closed form solution is used for solving the bending problem of simply supported doubly curved shell panels subjected to bi-sinusoidal transverse pressure. The BTDs built from non-polynomial functions are compared with Maclaurin expansions. Spherical shell panels with different layer-configurations are investigated. The results demonstrated that the shell models obtained from the BTD using non-polynomial terms can improve the accuracy obtained from Maclaurin expansion for a given number of unknown variables of a displacement field. © 2019Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Influence of Stipa ichu on the thermal and mechanical properties of adobe as a biocomposite material
No full textA millenary building material that has been used in many cultures is "adobe". In the Peruvian Andean regions during the winter, the temperature decreases drastically (+5 to -15°C), affecting the health of people of vulnerable age, agriculture and bovine livestock. Bioclimatic techniques must be considered to provide a comfortable thermal environment in the interior of housing. Furthermore, knowing the thermal conductivity of the elements that compose the houses allows us to perform thermal exchange simulations before construction is developed. Specifically, in this investigation, the thermal conductivity of adobe with and without Stipa ichu was measured as 0.371 W/m K and 0.349 W/m K, respectively, considering the norm ASTM C177 for that purpose. The mechanical behavior is as important as the thermal properties, and a value of 2.41 N/mm2 was obtained for unit compression. Additionally, scanning electron microscopy (SEM) mages of adobe samples were evaluated to investigate the internal composition, and X-ray diffraction (XRD) was used to determine the type of clay present. According to these results, our adobe has favorable thermal and mechanical performance. © Published under licence by IOP Publishing Ltd.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Validation of high-frequency ultrasound crawling waves sonoelastography
No full textSkin diseases cause changes in the elasticity of the skin. Recently, a new ultrasound method which combines crawling waves elastography with a high-frequency ultrasound (HF-US) system was reported for the estimation of skin elasticity. This study applies crawling waves method with an HF-US system in homogeneous and heterogeneous phantoms with similar shear wave speeds found in the literature to validate this technique. In addition, estimation performance was compared between the Phase Derivative (PD) estimator and the Regularized Wave-length Average Velocity Estimator (R-WAVE). Results corroborate the feasibility of this method. Additionally, it suggests that R-WAVE estimator can provide better measurements than PD with a lower coefficient of variation and fewer artifacts. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Agrosilvopastoril v 19.1: Modeling cattle production and environment contribution of silvopastoral systems in the peruvian tropics
Get PDFSimulation tools can be helpful for supporting implementation of livestock production systems and exploring ways of improvements. The aim of this paper is to present a support tool for implementation and evaluation of silvopastoral systems in the Peruvian Amazon Region. This approach is based on the design of a decision support model called Agrosilvopastoril v 19.1. It calculates livestock production using integrated information on climate, soil, crops, forestry, pastures and cattle herds collected from secondary sources and on-field work conducted at the Peruvian Northern Amazon Region. The model was tested to estimate carbon sequestration and enteric methane emissions in 10 has of silvopastures with different proportions of forest and pasture, showing an increase in carbon sequestration with a small reduction in the number of animals and similar methane emissions.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
A unified splitting algorithm for composite monotone inclusions
No full textOperator splitting methods have been recently concerned with inclusions problems based on composite operators made of the sum of two monotone operators, one of them associated with a linear transformation. We analyze here a general and new splitting method which indeed splits both operator proximal steps, and avoiding costly numerical algebra on the linear operator. The family of algorithms induced by our generalized setting includes known methods like Chambolle-Pock primal-dual algorithm and Shefi-Teboulle Proximal Alternate Direction Method of Multipliers. The study of the ergodic and non ergodic convergence rates show similar rates with the classical Douglas-Rachford splitting scheme. We end with an application to a multi-block convex optimization model which leads to a generalized Separable Augmented Lagrangian Algorithm.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy