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1
artículo
Peru’s Amazon rainforest is being destroyed because the timber industry only uses 3% of trees per hectare. Therefore, timber companies cannot be established in the forest, and 97% of trees are unused. These trees are eventually burned to clear land for formal and informal agriculture. This article proposes to use more trees given that records of the last 40 years show that all tree species can be used for some purpose if they are processed appropriately with simple sawmill and drying techniques. The analysis shows that if less than 7% of the available trees is used, it will be financially and economically feasible to establish primary industries in the forest itself. This creates permanent job positions and enables a sustainable use and renovation of the forest; thus ensuring the preservation of the Amazon rainforest, which does not allow growing any foreign tree species.
2
artículo
Peru’s Amazon rainforest is being destroyed because the timber industry only uses 3% of trees per hectare. Therefore, timber companies cannot be established in the forest, and 97% of trees are unused. These trees are eventually burned to clear land for formal and informal agriculture. This article proposes to use more trees given that records of the last 40 years show that all tree species can be used for some purpose if they are processed appropriately with simple sawmill and drying techniques. The analysis shows that if less than 7% of the available trees is used, it will be ?nancially and economically feasible to establish primary industries in the forest itself. This creates permanent job positions and enables a sustainable use and renovation of the forest; thus ensuring the preservation of the Amazon rainforest, which does not allow growing any foreign tree species.
3
artículo
Peru’s Amazon rainforest is being destroyed because the timber industry only uses 3% of trees per hectare. Therefore, timber companies cannot be established in the forest, and 97% of trees are unused. These trees are eventually burned to clear land for formal and informal agriculture. This article proposes to use more trees given that records of the last 40 years show that all tree species can be used for some purpose if they are processed appropriately with simple sawmill and drying techniques. The analysis shows that if less than 7% of the available trees is used, it will be financially and economically feasible to establish primary industries in the forest itself. This creates permanent job positions and enables a sustainable use and renovation of the forest; thus ensuring the preservation of the Amazon rainforest, which does not allow growing any foreign tree species.
4
tesis de grado
Publicado 2016
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The diabetic maculopathy is the pathophysiological consequence of VEGF action. The use of anti-VEGF (Bevacizumab) intravitreal has demonstrated efficacy and safety. Objectives: To determine the effect of treatment with anti-VEGF (Bevacizumab) intravitreal on visual acuity in patients with diabetic maculopathy. Method: A case-control study was conducted. The population are patients with diabetic maculopathy. Patients found improvement in visual acuity (logMAR delta greater than or equal to 0.3) and no improvement in visual acuity (delta less than 0.3 logMAR). Medical records were reviewed and cases (n = 50) who were treated with intravitreal injection of 1 or more doses of Bevacizumab and controls (n = 50), who they did not receive Bevacizumab (other treatments) were identified. Descriptive statistics, chi-square test of association and Z test for proportions was used. Results: 58 men and...
5
objeto de conferencia
Previous studies have demonstrated that attenuation coefficients can be useful towards characterizing thyroid tissues. In this work, ultrasonic attenuation coefficients were estimated from healthy human thyroids in vivo using a clinical scanner. The selected subjects were five young, healthy volunteers (age: 26 ± 6 years old, gender: three females, two males) with no reported history of thyroid diseases, no palpable thyroid nodules, no smoking habits, and body mass index less than 30 kg/m2. Echographic examinations were conducted by a trained sonographer using a SonixTouch system (Ultrasonix Medical Corporation, Richmond, BC) equipped with an L14-5 linear transducer array (nominal center frequency of 10 MHz, transducer footprint of 3.8 cm). Radiofrequency data corresponding to the collected echographic images in both transverse and longitudinal views were digitized at a sampling rate of...
6
artículo
Publicado 2022
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Objective. The purpose of this study is to determine the prognostic value of the absolute decrease in the N-terminal portion of pro-B-type natriuretic peptide (NT-proBNP) to prevent fewer clinical events, in the population of CLUSTER-HF (efficacy of ultrasound lung to guide therapy and prevent readmissions in heart failure). Materials and methods. This study was conducted in a subgroup of ninety-four patients with available NT-proBNP information at hospital discharge and prior to randomization in the CLUSTER-HF study. The primary objective of the study was to determine the prognostic value of absolute NT-proBNP decline below which fewer events of all-cause death, emergency room visits, and rehospitalization for heart failure at 180 days. Results. The absolute decrease in NT-proBNP below 3,350 pg/mL has a moderate discriminative capacity with AUC= 0.602, with a prognostic value in the com...
7
artículo
Publicado 2022
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Objective. The purpose of this study is to determine the prognostic value of the absolute decrease in the N-terminal portion of pro-B-type natriuretic peptide (NT-proBNP) to prevent fewer clinical events, in the population of CLUSTER-HF (efficacy of ultrasound lung to guide therapy and prevent readmissions in heart failure). Materials and methods. This study was conducted in a subgroup of ninety-four patients with available NT-proBNP information at hospital discharge and prior to randomization in the CLUSTER-HF study. The primary objective of the study was to determine the prognostic value of absolute NT-proBNP decline below which fewer events of all-cause death, emergency room visits, and rehospitalization for heart failure at 180 days. Results. The absolute decrease in NT-proBNP below 3,350 pg/mL has a moderate discriminative capacity with AUC= 0.602, with a prognostic value in the com...
8
artículo
Publicado 2025
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Introduction: Access to contraceptive methods in Venezuelan immigrant women residing in Peru presents limitations due to multiple factors that directly impact their ability to obtain and use them. Objective: To describe the prevalence and explore the factors associated with the use of contraceptive methods among Venezuelan immigrant women in Peru during 2022. Methods: Cross-sectional analytical study of secondary data from the second Survey of the Venezuelan Population Residing in Peru (ENPOVE). The generalized linear Poisson model with log-link function was used and crude prevalence ratios (PRc) and adjusted prevalence ratios (PRa) were calculated with their respective 95% confidence intervals (95% CI). Results: The prevalence of access to contraceptive methods was 50%. Access to contraceptive methods was higher in those Venezuelan immigrant women who were young (PRa: 3.12; 95 % CI: 1.7...
9
informe técnico
Publicado 2021
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The liquid product obtained from tire pyrolysis process, called tire pyrolysis oil (TPO), has a great attraction as an alternative fuel, as it has a viscosity of 5.43 cSt (Sharma et al., 2016), density of 921 kg/m³ (Gamboa et al., 2020), surface tension of 0.028 N/m (Chumpitaz et al., 2019), and higher heating value of 46.32 MJ/kg (Das et al., 2017), which are similar to diesel oil. These physical and chemical properties have motivated research into its application in furnaces, boilers and compression ignition engines. Generally, TPO is blended with diesel or biodiesel in order to decrease the percentage of sulfur and improve the cetane number of the fuel blend (Sharma et al., 2016). However, the evaluation of the quality and applicability of TPO has been focused mainly on combustion emissions and the performance of thermal equipment fueled with this fuel (and diesel/biodiesel blends), ...
10
informe técnico
Publicado 2021
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The liquid product obtained from tire pyrolysis process, called tire pyrolysis oil (TPO), has a great attraction as an alternative fuel, as it has a viscosity of 5.43 cSt (Sharma et al., 2016), density of 921 kg/m³ (Gamboa et al., 2020), surface tension of 0.028 N/m (Chumpitaz et al., 2019), and higher heating value of 46.32 MJ/kg (Das et al., 2017), which are similar to diesel oil. These physical and chemical properties have motivated research into its application in furnaces, boilers and compression ignition engines. Generally, TPO is blended with diesel or biodiesel in order to decrease the percentage of sulfur and improve the cetane number of the fuel blend (Sharma et al., 2016). However, the evaluation of the quality and applicability of TPO has been focused mainly on combustion emissions and the performance of thermal equipment fueled with this fuel (and diesel/biodiesel blends), ...
11
tesis de grado
Publicado 2015
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En este estudio se identifican los episodios de variaciones extremas en las salidas y entradas de flujos de capital (inflows y outflows) que ha experimentado el Perú durante el período l990:T1-2014:T4. Estimando regresiones log-log complementarias se identifican también los factores asociados a la probabilidad de experimentar algunos de esos episodios. Los resultados muestran que las variaciones extremas de los inflows Perú coinciden con períodos de gran estrés financiero como México 1994, Rusia 1998 y EE.UU 2008. Los factores determinantes de estos episodios serian el riesgo global, el nivel de actividad económica mundial, el ciclo de precios de nuestras exportaciones, la tasa de crecimiento doméstica y el déficit de cuenta corriente. Por otro lado, las variaciones extremas de los outflows se muestran menos relacionadas a períodos de gran estrés financiero y responderían fu...
12
tesis de grado
Publicado 2024
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Demostrar si el tamaño tumoral mayor de 5 cm es un factor pronóstico para la disminución de sobrevida actuarial de los pacientes con sarcoma primario de mama. Materiales y métodos: Estudio de casos y controles anidado a cohorte, donde se incluyó 20 historias clínicas de pacientes adultas con diagnóstico de sarcoma primario de mama entre los años 2010 al 2020, de los cuales se dividió en 2 grupos: 13 con tamaño tumoral mayor igual a 5 cm y 7 con tamaño tumoral menor a 5 centímetros. Las pruebas estadísticas fueron Regresión de Cox, test de Log rank, prueba de t Student y la prueba de Fisher. Resultados: Los pacientes con sarcoma primario de cáncer de mama con un tamaño tumoral menor a 5 cm tuvieron una sobrevida de 51.7 semanas, mientras que la sobrevida de los pacientes con sarcoma primario de cáncer de mama con un tamaño tumoral mayor a 5 cm fue de 95.6 semanas, estad...
13
tesis de grado
Publicado 2025
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Este estudio presenta como objetivo identificar a la hiperglicemia como un marcador pronóstico de mortalidad en pacientes hospitalizados con COVID–19, sin antecedentes de diabetes mellitus, en el Hospital Santa Rosa de Piura. Materiales y métodos: se utilizó un diseño observacional, analítico de cohorte retrospectivo, en un muestreo no probabilístico para estudio de cohorte, el tamaño de muestra es de 198 pacientes, de los cuales 66 son del grupo de los expuesto, y 132 pacientes de los no expuestos. Se emplearon pruebas como Wilcoxon, Log–Rank-Test para la curva de supervivencia de Kaplan–Meier, y por último se utilizó un modelo multivariado con Risk Ratio (RR) con una significancia ≤0.05 con un IC de 95%. Resultados: El estudio presenta un total de 198 pacientes, de los cuales 66 son expuestos, en donde el 82.19% de pacientes fallecieron, mientras el 95.20% de los pacie...
14
tesis de maestría
Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Recursos Hídricos
15
artículo
Publicado 2006
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Objective. The aim of this study was to evaluate the association between the eruption stage of the lower first permanent molar and dental plaque acidogenicity. Socio-economic status (SES), gender, and oral hygiene condition were also variables considered. Material and methods. 230 children between 6 and 8 years of age were recruited from one public and one private primary school with different SES in Lima, Peru. Clinical examinations were performed to assess lower first permanent molar eruption stage, plaque acidogenicity, and oral hygiene condition. Bivariate associations were analyzed through chi-square tests and the variable interactions were analyzed through a hierarchical log-linear analysis with backward elimination. Results. 21.8% of the population had highly acidogenic plaque, 34.3% acidogenic plaque, and 43.9% non-acidogenic plaque. Of the lower first permanent molars, 46.1% w...
16
tesis de grado
Publicado 2025
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Objetivo: Determinar que en pacientes con diagnóstico de cáncer gástrico avanzado la presencia de ganglios metastásicos mayor e igual a 7 poseen un pronóstico ominoso en sobrevida global en comparación con los que tienen menos de 7 adenopatías después de cirugía radical y quimioterapia adyuvante. Materiales y Métodos: El presente estudio de casos y controles analizó 100 pacientes con diagnóstico de cáncer gástrico avanzado tratados con gastrectomía radical más quimioterapia adyuvante. La supervivencia se analizó mediante la prueba estadística de Kaplan-Meier y se compararon curvas de sobrevida con la prueba log-rank. Se utilizó Chi-cuadrado para variables categóricas y regresión logística para análisis multivariado. Se consideró que existía una diferencia significativa si el valor de p era menor de 0.05 (p < 0.05). Resultados: En el análisis bivariado la supervi...
17
artículo
Publicado 2021
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Objective: To study the good prognostic factors, overall survival (OS) and progression-free survival (PFS) in a group of patients who underwent an intramedullary ependymoma surgery. Such factors are related to the patient, tumor, type of surgical resection and adjunctive treatment. Materials and methods: A retrospective, analytical and descriptive study conducted in 40 patients who underwent an intramedullary ependymoma surgery between 1985 and 2017 at the Instituto Nacional de Enfermedades Neoplásicas (INEN). The research used IBM SPSS Statistics for Windows 2017. The survival rate was estimated using the Kaplan-Meier product-limit model. The comparison of survival curves was determined by the log-rank test. A probability (p value) less than 0.05 was considered as statistically significant. Results: Out of the 40 patients, 33 were adults and seven were children. The male to female rati...
18
artículo
Publicado 2022
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Objetivo. Determinar el valor pronóstico del descenso absoluto de la porción N-terminal del propéptido natriurético tipo B (NT–proBNP) para prevenir menos eventos clínicos en la población del estudio CLUSTER-HF (eficacia del ultrasonido pulmonar para guiar la terapia y prevenir las rehospitalizaciones en insuficiencia cardiaca). Materiales y métodos. El presente estudio fue realizado en un subgrupo de 94 pacientes con información disponible de NT-proBNP al alta hospitalaria y previo a la aleatorización del estudio CLUSTER-HF. El objetivo primario del estudio fue determinar el valor pronóstico de descenso absoluto de NT - pro-BNP por debajo del cual se prediga menos eventos de muerte por todas las causas, visitas a urgencias y rehospitalización por insuficiencia cardiaca a 180 días. Resultados. El descenso absoluto de NT-proBNP por debajo de 3 350 pg/mL tiene una capacidad d...
19
artículo
Publicado 2024
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Objective: To assess the association between ethnicity and self-reported refractive errors (REs) among Peruvian children aged 7–11 years. Materials and methods: We conducted a cross-sectional study incorporating a secondary data analysis of 2017–2021 data from the Peruvian Demographic and Health Survey (DHS). REs and ethnicity were obtained from focal child's mother's report. Four outcomes were assessed: hyperopia, myopia, astigmatism and any RE. We included potential confounders, such as age, sex, wealth index, area of residence, region of origin, frequency of watching TV and watching screens at less than 30 cm distance. Generalised linear models with the Poisson family and log link function were used to calculate crude prevalence ratio and adjusted prevalence ratio (aPR) with 95% confidence intervals (95% CI). Results: Data from a total of 52,753 children were included. The prevale...
20
tesis de grado
Publicado 2019
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El presente trabajo de investigación de ingeniería “Estudio Hidrológico e Hidráulico para el dimensionamiento Optimizado del Puente Vehicular sobre el rio Cumbaza en la localidad Juan Guerra-Distrito Juan Guerra-Provincia de San Martin- San Martin 2018”, que presenta una altitud media de 201 m.s.n.m. con un clima cálido típica de Juan Guerra, ubicándose el tramo de interés en el rio Cumbaza. Se realizará para contribuir técnicamente con el aporte del estudio hidrológico e hidráulico, ya que para el diseño del puente en referencia se hace necesario disponer de estudios básicos de ingeniería, el cual aportara con el valor de los parámetros necesarios para realizar el dimensionamiento hidráulico optimizado de dicha estructura. Para tal fin se calculó los parámetros de la cuenca del rio Cumbaza en la sección de interés donde se emplazara el puente vehicular, con la f...
