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1
artículo
Publicado 2023
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The article analyzes deforestation and forest loss in the Condorcanqui Province, Amazonas, during the 2001 to 2020 time period. It is observed that year 2020 experienced the highest deforestation rate, indicating a significant increase compared to previous years. This large-scale deforestation can have serious environmental consequences, such as, biodiversity loss and increased greenhouse gas emissions. On the other hand, year 2009 shows the lowest deforestation rate, indicating a decrease in forest loss compared to the previous year. However, a negative rate does not necessarily imply a net increase in forest coverage, as it can reflect regeneration or compensation processes in previously affected areas. Illegal logging is identified as one of the main causes of deforestation, and the responsibility of state institutions to control and combat this activity, promoting sustainable forest ...
2
tesis de maestría
Publicado 2017
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The attenuation coefficient slope (ACS) has the potential to be used for tissue characterization and as a diagnostic ultrasound tool, hence complementing B-mode images. The ACS can be valuable for estimation of other ultrasound parameters such as the backscatter coefficient. There is a well-known tradeoff between the precision of the estimated ACS values and the data block size used in spectral-based techniques such as the spectral log difference (SLD). This trade-off limits the practical usefulness of spectral-based attenuation imaging techniques. In this thesis work, the regularized spectral log difference (RSLD) technique is presented in detail and evaluated with simulations and experiments with physical phantoms, ex vivo and in vivo. The ACS values obtained when using the RSLD technique were compared to the ones obtained when using the SLD technique, as well as the ground truth ACS v...
3
tesis de maestría
Publicado 2017
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The attenuation coefficient slope (ACS) has the potential to be used for tissue characterization and as a diagnostic ultrasound tool, hence complementing B-mode images. The ACS can be valuable for estimation of other ultrasound parameters such as the backscatter coefficient. There is a well-known tradeoff between the precision of the estimated ACS values and the data block size used in spectral-based techniques such as the spectral log difference (SLD). This trade-off limits the practical usefulness of spectral-based attenuation imaging techniques. In this thesis work, the regularized spectral log difference (RSLD) technique is presented in detail and evaluated with simulations and experiments with physical phantoms, ex vivo and in vivo. The ACS values obtained when using the RSLD technique were compared to the ones obtained when using the SLD technique, as well as the ground truth ACS v...
4
tesis de maestría
Publicado 2017
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The attenuation coefficient slope (ACS) has the potential to be used for tissue characterization and as a diagnostic ultrasound tool, hence complementing B-mode images. The ACS can be valuable for estimation of other ultrasound parameters such as the backscatter coefficient. There is a well-known tradeoff between the precision of the estimated ACS values and the data block size used in spectral-based techniques such as the spectral log difference (SLD). This trade-off limits the practical usefulness of spectral-based attenuation imaging techniques. In this thesis work, the regularized spectral log difference (RSLD) technique is presented in detail and evaluated with simulations and experiments with physical phantoms, ex vivo and in vivo. The ACS values obtained when using the RSLD technique were compared to the ones obtained when using the SLD technique, as well as the ground truth ACS v...
5
artículo
Publicado 2025
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Background. Because of illegal logging, habitat fragmentation, and high value timber Andean montane forest Cedrela species (such as Cedrela angustifolia), is endangered in Central and South America. Studying the effects of climate change and tree cover loss on the distribution of C. angustifolia will help us to understand the climatic and ecological sensitivity of this species and suggest conservation and restoration strategies. Methods. Using ecological niche modeling with two algorithms (maximum entropy (MaxEnt) and Random Forest) under the ecological niche conservatism approach, we generated 16,920 models with different combinations of variables and parameters. We identified suitable areas for C. angustifolia trees under present and future climate scenarios (2040, 2070, and 2100 with SSP 3-7.0 and SSP 5-8.5), tree cover loss, and variables linked to soil and topography. Results. Our r...
6
artículo
The objective of this article was to systematize the evidence of deforestation and determine the main factors of forest loss in the department of Madre de Dios, Peru. A search was carried out for scientific research related to "deforestation", "Peruvian Amazon deforestation", deforestation Madre de Dios". Scientific articles published in a database of indexed journals were analyzed. A descriptive, non-experimental study design was chosen. For data collection, the document analysis technique was applied. Based on the evidence, it is concluded that the areas of most significant deforestation are concentrated in the southern Amazon, mainly in Madre de Dios. In addition, the main factors of forest loss are illegal mining and mostly illegal agricultural activities; within these two activities, illegal mining is the cause of the highest percentage. Negative aspects such as the loss of bi...
7
artículo
Publicado 2020
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Introduction: Hearing loss is a frequent occupational disease and causes deterioration in the quality of life of workers. Objetive: The objective was to identify the prevalence and factors associated with noise-induced hearing loss in workers of a metalworking company. Material and Methods: Analytical cross-sectional study. Data from occupational medical records were used to determine the frequency of hearing loss due to noise and its potential associated factors (age, sex, personal history). Simple and multiple regression models were constructed, estimating prevalence ratios (RP) using generalized linear models, Poisson family and log link function. Results: Of 1543 workers, the average age was 36.7 years and the majority were male (93.6%). Only 8.2% reported illness and / or occupational accident prior to the occupational evaluation. 10.7% had hearing loss due to noise. The frequency o...
8
artículo
Publicado 2014
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One of main factors identified as explaining forest loss and degradation in the Selva (the Peruvian Amazon) is the migration of people from the Sierra (Andes highlands), where agricultural conditions are severe, to forest areas in the Selva in search of new land. This paper aims at clarifying the characteristics and process of migration based on interviews with local people near Pucallpa, Ucayali Department, where forest loss and degradation has advanced in recent decades. In the study area, forest loss and degradation progressed by commercial logging after construction of a road connecting between Lima and Pucallpa in 1943. After logging, stock-farming companies and immigrants entered the area, and land uses other than high forest have been expanding. Today, the study area is occupied by people who have immigrated since the 1960s. Many of them earned income by logging until the 1980s, w...
9
tesis de grado
Publicado 2023
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El presente documento trata sobre la implementación de un nuevo sistema de auditoría asíncrona en Minotech, una empresa latinoamericana líder en proveer sistemas de puntos de venta para el comercio minorista. Los dispositivos de la empresa se comunican de forma directa con su centro de datos a través de servicios web. Se identificó un problema en estos servicios: el sistema de auditoría anterior, responsable de registrar las solicitudes de las APIs de la empresa, sufría pérdidas significativas de datos cuando había fallas o interrupciones en el proceso de almacenamiento en la base de datos. Esta situación generaba problemas graves al requerir el uso de la información auditada, ya que los datos a menudo no eran fiables. Para abordar este problema, se desarrolló e implementó un nuevo sistema de auditoría centrado en asegurar la integridad de los datos durante su procesamient...
10
tesis de grado
Publicado 2023
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Universidad Nacional Agraria La Molina. Facultad de Ciencias Forestales. Departamento Académico de Industrias Forestales
11
tesis de grado
Estudio de las propiedades físicas y mecánicas de la madera copaiba en el departamento de San Martín
Publicado 1999
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Wood was probably the first material used for structural purposes by man. Currently a growing interest in this material, which is largely due to their living nature, indeed wood is the only renewable natural resource endowed with good structural properties is observed. The growing demands of housing programs due to population growth make it increasingly demand and use of wood, for this reason it is important to know their mechanical physical properties and thus carry out a good design with this material under study to be determined in the laboratory. Regarding the constructive aspect it should be noted that wood is a relatively easy material work with simple tools, making it possible to achieve a wide variety of shapes and sections. Its lightness means of transport and assembly costs low which is significant when it comes to building a system based on pre-production. For all these mentio...
12
artículo
Publicado 2020
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The threatened Peruvian Plantcutter Phytotoma raimondii is a restricted-range species, endemic to the north coast of Peru. As a specialist herbivore, it is only found at sites with an adequate diversity of xerophytic flora. Although it is recognized that the species is under threat from habitat degradation and loss, little or no attempt has been made to measure these changes. This study catalogues the floral diversity and degradation of sites near Lobitos town, north of Talara, to determine the loss of this species´ habitat. Fieldwork was conducted between November 2019 and January 2020. All larger plants (with a diameter ≥ 5 cm near ground level) and all deforested Prosopis pallida (Algarrobo) stumps were georeferenced over a 10 ha plot at the main site of Cerro Blanco, c. 2 km south of Lobitos. The height, width and general health of each bush were noted, and the diameter of P. pall...
13
artículo
Publicado 2020
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The threatened Peruvian Plantcutter Phytotoma raimondii is a restricted-range species, endemic to the north coast of Peru. As a specialist herbivore, it is only found at sites with an adequate diversity of xerophytic flora. Although it is recognized that the species is under threat from habitat degradation and loss, little or no attempt has been made to measure these changes. This study catalogues the floral diversity and degradation of sites near Lobitos town, north of Talara, to determine the loss of this species´ habitat. Fieldwork was conducted between November 2019 and January 2020. All larger plants (with a diameter ≥ 5 cm near ground level) and all deforested Prosopis pallida (Algarrobo) stumps were georeferenced over a 10 ha plot at the main site of Cerro Blanco, c. 2 km south of Lobitos. The height, width and general health of each bush were noted, and the diameter of P. pall...
14
tesis de grado
Publicado 2018
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El presente estudio se realiza para identificar el problema general y problemas específicos de gestión en la empresa “JUNIOS ETIQUETAS Y ADHESIVOS S.A.C.” Como problema general podemos decir que existe carencia de sistema de información por lo cual ocasiona desorden y pérdida de información interna con respecto a los clientes y proveedores, lo cual se refleja en las fechas de entrega extemporáneamente. Esto conlleva a que los colaboradores del área de logística y sus almacenes realicen un trabajo ineficiente, se limitan en la asignación de recursos económicos lo cual ocasionando un déficit en las ventas. En lo consecutivo de acuerdo a nuestra investigación observamos otros problemas secundarios que podemos observar dentro de la casuística a lo largo de la investigación; queremos lograr incrementar las ventas y analizar los problemas internos que suceden en esta empresa ...
15
tesis de grado
Publicado 2014
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This research work is justified, since the expert evaluation, carried out to date by competent bodies, for cases of crimes against forests or forest formations, intends to make an administrative technical procedures manual, allowing you to standardize the conduct of the surveys for cases of crimes against forests or wooded formations~ which facilitates effectively to protecting forests, preventing and repairing damage caused by deforestation, of which having as objectives review, analyze and contrast legal technical reports, issued by the experts in environmental, for cases of crimes against forests or forest formations, conducting field inspections: in the districts of Chazuta (Sector Aguano Muyuna and land two brothers)~ La Banda de Shilcayo district (Sector Metozapa, community of Polish and Sector San Juan, village Sinamipampa)~ Barranquita district (High Ushpayacu and Italy new Secto...
16
tesis de grado
Publicado 2019
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Esta investigación se realizó en la Universidad privada de Trujillo, tuvo como objetivo de determinar el diseño estructural - hidráulico que se debe considerar para realizar la defensa ribereña del Rio Chicama, Tramo Puente San Polo – Baños Chimú, 2018. La investigación es cuantitativa, de tipo no experimental. Tomándose como muestra 2.00 Km del cauce del rio Chicama; se utilizó como técnica la observación y se desarrolló un cuadro de clasificación de variables para el análisis de los resultados. En el trabajo realizado, se determinó que el Diseño estructural - hidráulico de una defensa ribereña, debe ser de revestimiento con enrocado, por el alto riesgo de inundaciones que existe en la zona y las pérdidas que se producen, las cuales son económicas, pues impactan de manera negativa en la economía de los pobladores, (agricultura y ganadería); de transporte, pues p...
17
artículo
Publicado 2025
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Background: Stingless bees (Apidae: Meliponini) are critical pollinators in the Peruvian Amazon, sustaining biodiversity, crop productivity, and indigenous livelihoods. Despite their ecological and economic importance, the effects of deforestation and illegal logging on their populations remain poorly understood. Nesting tree loss, habitat fragmentation, and changes in elevation influence stingless bee distribution, yet conservation efforts remain insufficient due to a lack of spatial data on their vulnerability. Results: This study examines the spatial distribution, elevation trends, and deforestation threats affecting Melipona eburnea and Tetragonisca angustula, with a focus on tree nesting preferences in the Biosphere Reserve Avireri-Vraem. Using literature reviews, field observations, and GPS surveys, we assessed species distribution patterns, deforestation risks, and nesting tree as...
18
artículo
Publicado 2024
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Vector-borne diseases (VBDs) are major threats to human health. They are estimated to cause more than 700,000 deaths each year. This presents serious health problems for CBD. In recent years, the incidence of VBDs has increased globally, affecting one billion people approximately and accounting for 17% of all infectious diseases. Globally, disease rates have risen at an alarming rate, with more than 3.9 billion people at risk of infection. Therefore, it is essential to find approaches to detect these diseases; this is where machine learning (ML) models come into play. The purpose of this study was to predict VBDs using tabular epidemiological data. For this purpose, a set of ML models was used, such as support vector classifier (SVC), extreme gradient boosting (XGBoost), LightGBM, CatBoost, random forest (RF), and balanced random forest (BRF). A dataset consisting of 65 features and 1262...
19
objeto de conferencia
Publicado 1998
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Trabajo presentado en el Workshop on Carbon Pools and Dynamics of Tropical Ecosystems, Belem, Brazil. Del 1 al 5 de diciembre, 1997.
20
artículo
La pancreatina, sustancia conformada por la mezcla de enzimas digestivas, con aplicaciones en el campo médico-farmaceútico, por su origen y método de producción requiere ser sometida a un proceso de descontaminación. Así, muestras de pancreatina en polvo fueron empacadas en bolsas de polietileno de baja densidad y tratadas con radiación gamma a las dosis de 2, 3, 5, 6, 7, 8, 13 y 25 kGy. Se realizaron las pruebas microbiológicas y físico-químicas, indicadas en la US Pharmacopea, a las muestras irradiadas y control, para determinar la dosis óptima de descontaminación que permitiría el uso comercial del producto. Se determinó que las dosis mínima de 5 kGy era adecuada para descontaminar el producto ya que se lograba disminuir 3 ciclos logarítmicos de la carga inicial de microorganismos aerobios mesófilos en la muestra control, que incluía bacilos esporulados. De igual mod...
