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Item A Comprehensive Systematic Review of Neural Networks and Their Impact on the Detection of Malicious Websites in Network Users(2023-01) Gamboa-Cruzado, Javier; Briceño-Ochoa, Juan; Huaysara-Ancco, Marco; Alva Arévalo, Alberto; Ríos Vargas, Caleb; Aranguena Yllanes, MagalyThe large branches of Machine Learning represent an immense support for the detection of malicious websites, they can predict whether a URL is malicious or benign, leaving aside the cyber attacks that can generate for network users who are unaware of them. The objective of the research was to know the state of the art about Neural Networks and their impact for the Detection of malicious Websites in network users. For this purpose, a systematic literature review (SLR) was conducted from 2017 to 2021. The search identified 561 963 papers from different sources such as Taylor & Francis Online, IEEE Xplore, ARDI, ScienceDirect, Wiley Online Library, ACM Digital Library and Microsoft Academic. Of the papers only 82 were considered based on exclusion criteria formulated by the author. As a result of the SLR, studies focused on machine learning (ML), where it recommends the use of algorithms to have a better and efficient prediction of malicious websites. For the researchers, this review presents a mapping of the findings on the most used machine learning techniques for malicious website detection, which are essential for a study because they increase the accuracy of an algorithm. It also shows the main machine learning methodologies that are used in the research papers.Item Altitude and Its Association with Low Birth Weight among Children of 151,873 Peruvian Women: A Pooled Analysis of a Nationally Representative Survey(2023-01) Hernández Vásquez, Akram; Bartra Reátegui, Alicia; Vargas Fernández, RodrigoThe aim of this study was to determine the relationship between the altitude of residence and the low birth weight (LBW) of the children of pregnant Peruvian women using a nationally representative database. An analysis of individual-level data from the last 13 years (from 2009 to 2021) of the Demographic and Family Health Survey was performed. The outcome variable was LBW, defined as birth weight less than 2500 g, while the independent variable was the altitude of residence in meters above sea level (masl). To estimate the association between the two variables, the crude and adjusted generalized linear model of the Poisson family with a log link was used along with crude and adjusted prevalence ratios, which were estimated with their respective 95% confidence interval. A total of 151,873 women aged 15–49 years were included between 2009 and 2021. The pooled proportion of LBW was 7.0%. As the main finding, the children of mothers residing at an altitude from 2500 to 3499 masl and ≥3500 masl had a higher probability of LBW. It was found that the children of mothers residing at an altitude above 2500 masl were more likely to have LBW. Our results will help to strengthen the cultural practice of maternal health care and increase its coverage in women residing in high-altitude regions.Item Análise dinâmico-mecânica: Aplicações em filmes comestíveis(2008-02) Mendieta Taboada, Oscar W.; De Carvalho, Rosemary A.; do A. Sobral, Paulo JoséEdible films are thin materials based on biopolymers and food additives. The aim of this work is a review on the application of dynamic mechanical analysis in edible film technology. After a brief review of the linear visco-elasticity theory, a description of some practical aspects related to dynamic mechanical analysis, such as sample fixation and sample dehydration during analysis and types and modes of tests are presented. Thus, the use of temperature scanning analysis for glass transition and for plasticizer-biopolymer compatibility studies and frequency scanning tests, less common in edible film technology, are critically reviewed.Item Avian malaria, haematocrit, and body condition in invasive wetland passerines settled in southwestern Spain(2023-01) Muriel, Jaime; Garcia-Longoria, Luz; Magallanes, Sergio; Ortiz, Juan Antonio; Marzal, AlfonsoAvian malaria and related haemosporidian parasites can negatively impact fitness in many songbirds. Research on the malaria infection and its physiological costs on their avian hosts is heavily skewed toward native passerines, with exotic species underrepresented. However, introduced species may carry on and spread new pathogens to native species, and play a role on parasite transmission cycle in invaded bird communities as pathogen reservoir. Here, we molecularly assess the prevalence and diversity of haemosporidian parasites in three introduced wetland passerines (the Red Avadavat Amandava amandava, the Yellow-crowned Bishop Euplectes afer, and the Common Waxbill Estrilda astrild) captured during the same season in southwestern Spain. We also explored the relation between parasite infection, body condition, haematocrit, and uropygial gland volume. We detected an overall parasite prevalence of 3.55%, where Common Waxbills showed higher prevalence (6.94%) than Red Avadavats (1.51%). None Yellow-crowned Bishops were infected with haemosporidians. Almost 60% of infections were caused by Leucocytozoon, and about 40% by Plasmodium. We identified four unique lineages of Plasmodium and three of Leucocytozoon. Moreover, 91% of the identified host–parasite interactions represented new host records for these haemosporidian parasites. Parasite infection was not related to body condition, haematocrit, and uropygial gland volume of the wetland passerines. Haematocrit values varied seasonally among bird species. Additionally, haematocrit was positively related to body condition in the Yellow-crowned Bishops, but not in the other species. Red Avadavats had higher haematocrit levels than Yellow-crowned Bishops, whereas Common Waxbills showed the lower haematocrit values. The uropygial gland volume was positively correlated with body condition in all bird species. Common Waxbills showed higher uropygial gland volumes related to their body size than birds from other two species. These outcomes highlight the importance of exotic invasive species in the transmission dynamics of haemosporidian parasites.Item Azadirachta indica y Jatropha curcas reducen el ataque de Hypsipyla grandella Zéller en Swietenia macrophylla King plantada en sistemas agroforestales(2022-04) Guerra-Arévalo, Héctor; Celis Espinoza, Diego Fernando; Diaz Visitación, Alfredo Iban; Vásquez-Vela, Ana Lucia Milagros; Arévalo-López, Luís Alberto; García-Soria, Diego Gonzalo; Revilla-Chávez, Jorge Manuel; Abanto-Rodriguez, Carlos; Arévalo-Gardini, Enrique; Del Castillo-Torres, Dennis; Guerra-Arévalo, Wilson FranciscoS. macrophylla es una importante especie forestal con valor económico, sin embargo, su principal problema es su vulnerabilidad ecológica al ataque de H. grandella. En ese sentido, el objetivo en este trabajo fue determinar el efecto de A. indica y J. curcas en la reducción del ataque de H. grandella en plantas de S. macrophylla plantada en sistemas agroforestales. Para ello, fue evaluado el diámetro basal (mm), altura de planta (cm), plantas atacadas (%), tallos atacados (%), ápices atacados (%), hojas atacadas (%), sobrevivencia y mortalidad de larvas (%). El menor porcentaje de ataque de H. grandella en plantas de S. macrophylla fue registrado en la asociación S. macrophylla con T. cacao y A. indica y también en S. macrophylla con T. cacao y J. curcas, plantadas a 1 m x 3 m, con 0,95 y 2,85%, respectivamente. Entre tanto, la mayor sobrevivencia y mortalidad de larvas de H. grandella fue registrado en la asociación S. macrophylla con T. cacao y en S. macrophylla con T. cacao y J. curcas con 90,20 y 88,89% respectivamente. De este modo, el uso de A. indica y J. curcas promueve significativamente la disminución del ataque de H. grandella en plantas de S. macrophylla plantada en sistemas agroforestales.Item Beta Diversity of Arbuscular Mycorrhizal Communities Increases in Time after Crop Establishment of Peruvian Sacha Inchi (Plukenetia volubilis)(2023-02) Ana Maria de la Sota Ricaldi; Sofía Rengifo del Águila; Raúl Blas Sevillano; Álvaro López-García; Mike Anderson Corazon-Guivin(1) Background: Beta diversity, i.e., the variance in species compositions across communities, has been pointed out as a main factor for explaining ecosystem functioning. However, few studies have directly tested the effect of crop establishment on beta diversity. We studied beta diversity patterns of arbuscular mycorrhizal (AM) fungal communities associated to sacha inchi (Plukenetia volubilis) after crop establishment. (2) Methods: We molecularly characterized the AM fungal communities associated to roots of sacha inchi in plots after different times of crop establishment, from less than one year to older than three. We analyzed the patterns of alpha, beta, and phylogenetic diversity, and the sources of variation of AM fungal community composition. (3) Results: Beta diversity increased in the older plots, but no temporal effect in alpha or phylogenetic diversity was found. The AM fungal community composition was driven by environmental factors (altitude and soil conditions). A part of this variation could be attributed to differences between sampled locations (expressed as geographic coordinates). Crop age, in turn, affected the composition with no interactions with the environmental conditions or spatial location. (4) Conclusions: These results point out towards a certain recovery of the soil microbiota after sacha inchi establishment. This fact could be attributed to the low-impact management associated to this tropical crop.Item Caracterización del valor nutricional de los residuos agroindustriales para la alimentación de ganado vacuno en la región de San Martín, Perú(2020-04) Godoy Padilla, David José; Daza La Plata, Rossmery; Fernández Curi, Lisania Melisa; Layza Mendiola, Anita Elizabeth; Roque Alcarraz, Roberto Edgardo; Hidalgo Lozano, Víctor; Gamarra Carrillo, Segundo Gregorio; Gómez Bravo, Carlos AlfredoSe realizó una caracterización nutricional de 10 residuos agroindustriales disponibles en San Martín, Perú. Se colectaron 19 muestras de residuos provenientes de 11 plantas agroindustriales dedicadas a la producción de aceite de palma, arroz, cacao, café, coco y chontaduro. Se determinó la materia seca (MS), proteína cruda (PC), extracto etéreo (EE), fibra cruda (FC), extracto libre de nitrógeno (ELN), ceniza, digestibilidad aparente in vitro de la materia seca (DIVMS), fibra detergente neutro (FDN), fraccionamiento de proteína, proteína cruda utilizable (uCP), nutrientes digestibles totales (NDT) y energía neta de lactación (ENL). Se encontraron diferencias significativas entre subproductos con respecto a su potencial nutricional (p < 0,05), siendo el nielen, arrocillo y polvillo de arroz, insumos energéticos con valores altos de ENL (2,1 ± 0,02, 2,1 ± 0,02 y 1,7 ± 0,02 Mcal/kg en base seca, respectivamente) y alta DIVMS (99,3 ± 0,25 %, 90,5 ± 0,42 % y 99,0 ± 0,68 %, respectivamente). Insumos con mayor aporte proteico fueron torta de coco y cascarilla de cacao (21,9 % y 21,8 ± 1,34 % de pc, respectivamente). La fibra de palma y cascarilla de arroz fueron residuos fibrosos con menor potencial de uso por su baja DIVMS (27,8 ± 2,45 % y 27,7 ± 5,02 %, respectivamente) y alto contenido de FDN (69,8 ± 4,17 % y 72,6 ± 6,45 %, respectivamente). La cáscara de palmito tuvo regular DIVMS (57,2 %) y alto FDN (60,4 %). Los residuos agroindustriales de San Martín tienen un variado potencial energético y proteico de utilidad en la alimentación de ganado vacuno.Item Caracterización genética de bacterias endofíticas de arroz (Oryza sativa L.) con actividad antimicrobiana contra Burkholderia glumae(2020-10) Valdez Nuñez, Renzo Alfredo; Ríos Ruiz, Winston Franz; Ormeño-Orrillo, Ernesto; Torres-Chávez, Edson E.; Torres Delgado, JorgeEl objetivo del presente estudio fue aislar y seleccionar bacterias endofíticas de arroz capaces de inhibir al fitopatógeno Burkholderia glumae THT, así como caracterizarlas por su genética y bioquímica. También se buscó caracterizar la diversidad genética y los factores de virulencia presentes en cepas de B. glumae y de Burkholderia gladioli, otro patógeno de arroz, aisladas de campo. Se colectaron plantas de arroz en 4 departamentos del norte de Perú, y tras la desinfección de tejidos se aislaron bacterias endofíticas por cultivo en agar soya tripticasa (30 °C; 48 h) y en medio selectivo (pH 4,5; 41 °C; 72 h). Se evaluó la actividad antimicrobiana frente a B. glumae THT, la producción de sideróforos y la resistencia a la toxoflavina, toxina producida por este agente. La identificación molecular se realizó mediante BOX-PCR y secuenciación del gen 16S ARNr. Además, se determinó la producción de enzimas extracelulares y se efectuaron ensayos de motilidad y sensibilidad/resistencia a bactericidas. Se aislaron 189 bacterias endofíticas, de las cuales solo 9 presentaron actividad antimicrobiana contra B. glumae THT, sobresaliendo Burkholderia vietnamiensis TUR04-01, B. vietnamiensis TUR04-03 y Bacillus aryabhattai AMH12-02. Estas cepas produjeron sideróforos y al menos el 55,5% fueron resistentes a la toxoflavina. Por otro lado, 17 de las cepas de B. glumae y B. gladioli aisladas se agruparon en 9 perfiles BOX-PCR, 16 de ellas presentaron similitud con B. glumae LMG2196T (100%) y una con B. gladioli NBRC13700T (99,86%). Hubo elevada diversidad de acuerdo al origen geográfico y se encontraron factores de virulencia. En conclusión, se hallaron cepas del género Bacillus y Burkholderia que podrían ser agentes de biocontrol contra B. glumae.Item Cover crop species and mycorrhizal colonization on soil phosphorus dynamics(2021-09) Arruda, Bruna; Herrera, Wilfrand Ferney Bejarano; Rojas García, José Carlos; Turner, Cyan; Pavinato, Paulo SergioPhosphorus (P) plays an important role in the physiological plant processes; however, in tropical soils, P is one of the most limiting nutrients for crop yield due to its low mobility, determined by the adsorption of this element to the soil. To enhance P-use and P-acquisition efficiency, this research aimed to evaluate the effect of cover crops and mycorrhizal colonization on changing soil P fractions, both organic and inorganic. A complete randomized block design was adopted in a field experiment, with four replications using four cover crops: i) pigeon pea (Cajanus cajan); ii) crotalaria (Crotalaria juncea); iii) millet (Pennisetum glaucum); iv) brachiaria (Brachiaria ruziziensis) and v) fallow, as control. The arbuscular mycorrhizal fungus colonization, the fungal spore density, soil P fractionation, and N, P, and K uptake were assessed. Our results show that cover crops affected the soil P cycling in deeper soil layers. Cover crops may increase arbuscular mycorrhizal inoculum potential for the succeeding crop in rotation or intercropping, when used as a green manure.Item COVID-19 in Latin America and the Caribbean: what is known about the status of school reopening?(2021-06) Fernandez-Guzman, Daniel; Sangster-Carrasco, Lucero; Pinedo Soria, AntonySince December 2019, the world has been facing a rapid increase in cases and deaths from the new coronavirus (COVID-19), forcing a response from countries all over the world to stop its transmission. Thus, at the beginning of April, 172 nations closed their schools, affecting >84.8% (~1484 million) of students enrolled worldwide, aiming to reduce the exposure to the virus, a social measure previously used to control the H1N1 influenza pandemic. It is difficult to assess the impact of schools closures on the incidence and mortality from COVID-19, given that it is not easy to carry out experimental studies, there is no scientific support confirms its effectiveness. However, during the influenza outbreaks, this strategy turned out to be a potentially useful intervention, despite not being able to determine the optimal moment to start and end this strategy, because of the concomitant use of other measures during the influenza outbreak; however, in mathematical models, where the school closure was considered as an isolated measure, a reduction between 2 and 4% of the total deaths was calculated during the virus outbreak.Item Density-Based Unsupervised Learning Algorithm to Categorize College Students into Dropout Risk Levels(2022-11) Valles Coral, Miguel Angel; Salazar Ramírez, Luis; Injante Ore, Richard Enrique; Hernandez Torres, Edwin Augusto; Juárez Díaz, Juan; Navarro Cabrera, Jorge Raul; Pinedo Tuanama, Lloy Pool; Vidaurre Rojas, PierreCompliance with the basic conditions of quality in higher education implies the design of strategies to reduce student dropout, and Information and Communication Technologies (ICT) in the educational field have allowed directing, reinforcing, and consolidating the process of professional academic training. We propose an academic and emotional tracking model that uses data mining and machine learning to group university students according to their level of dropout risk. We worked with 670 students from a Peruvian public university, applied 5 valid and reliable psychological assessment questionnaires to them using a chatbot-based system, and then classified them using 3 density-based unsupervised learning algorithms, DBSCAN, K-Means, and HDBSCAN. The results showed that HDBSCAN was the most robust option, obtaining better validity levels in two of the three internal indices evaluated, where the performance of the Silhouette index was 0.6823, the performance of the Davies–Bouldin index was 0.6563, and the performance of the Calinski–Harabasz index was 369.6459. The best number of clusters produced by the internal indices was five. For the validation of external indices, with answers from mental health professionals, we obtained a high level of precision in the F-measure: 90.9%, purity: 94.5%, V-measure: 86.9%, and ARI: 86.5%, and this indicates the robustness of the proposed model that allows us to categorize university students into five levels according to the risk of dropping out.Item Depression, anxiety, and stress in health professionals working during the covid-19 pandemic in Peru: An analytical cross-sectional study(2021-09) Quispe-Sancho, Alan; Chambi-Macedo, Katerin Lesly; Laurel-Vargas, Verónica; Huamani-Merma, Edson; Cuzcano-Gonzales, Katherine Vanesa; Huaita Rocha, Milagros Alexandra; Mendoza-Guillen, Lesly; Sanchez-Choquepata, Akemi Diana; Fuentes-Casani, Jheampiero; Bandeira, António; Tovani-Palone, Marcos Roberto; Mejia, Christian R.Objective: To determine the association between depression, anxiety, and stress according to sociodemographic and occupational factors in Peruvian health professionals during the coronavirus disease 2019 (COVID-19) pandemic. Methods: Cross-sectional analytical and multicentre study, based on a virtual survey sent to Peruvian health personnel (from the 25 Peruvian regions) working during the COVID-19 pandemic. The three dependent variables (depression, anxiety, and stress) were measured with the Depression, Anxiety, and Stress Scale-21 (DASS-21) (Cronbach’s Alpha: 0.93) and compared with sociodemographic and occupational variables. P-values were obtained through generalized linear models, adjusted for each location where the survey was sent. Results: Of the 550 participants, 2%, 13%, and 3% of them had severe or very severe depression, anxiety, and stress, respectively. In the multivariate analysis, we observed that professionals with a greater number of children had a lower frequency of severe depression (adjusted prevalence ratio (aPR): 0.37; 95% confidence interval (CI): 0.17-0.79; p = 0.010). In addition, physicians had a lower frequency of severe anxiety (aPR: 0.37; 95% CI: 0.18-0.75; p = 0.036), and professionals who lived in the Central region (aPR: 0.50; 95% CI: 0.25-0.97; p = 0.042) and in the South of the country (aPR: 0.37; 95% CI: 0.19-0.71; p = 0.003) had lower anxiety levels compared to those in the Northern region. With regard to severe stress, those who lived in the Central (aPR: 0.15; 95% CI: 0.03-0.75; p = 0.021) and South regions (aPR: 0.19; 95% CI: 0.04-0.79; p = 0.011) had lower stress levels. Conclusion: There were significant percentages of deteriorating mental health in Peruvian health professionals during the pandemic, which may have negative repercussions in the short-, medium-, and long-term. In this sense, additional governmental actions should be necessary to provide specific psychological and psychiatric support programs to these workers.Item Detection of bluetongue virus in sheep by real-time RT-PCR in different production systems in San Martin, Peru(2022-07) Alicia María López Flores; Roni David Cruz Vasquez; Víctor Humberto Puicón Niño de Guzmán; Alicia Bartra Reátegui; Orlando Ríos Ramírez; Fredy Fabián DomínguezThe present study aimed to determine the prevalence of Bluetongue Virus (BTV) in sheep, by the real-time Reverse Transcription-polymerase chain reaction (RT-PCR) technique. Three hundred sixty-six sheep from the ten provinces of the Peru region were evaluated. The methodology used was the collection of blood samples from the jugular vein of the sheep, then the process of extraction and purification of RNA was carried out with the QIAmp® kit, then the reverse transcription to obtain the cDNA, and finally perform the real-time RT-PCR, for which the SuperScript III platinium One-step qRT-PCR kit was used, with the primers and probes being directed to segment 10 of the NS3 gene of BTV. The results of the real-time RT-PCR test revealed two positive sheep with a value of cycle threshold (Ct) of 35.21 and 35.57, with a prevalence of 0.54 % of BTV-positive sheep in the extensive production system, with environmental conditions that favor the development of the Culicoides vector. It is concluded that, by means of the real-time RT-PCR technique, the presence of BTV in this region of Peru is confirmed, which makes future studies necessary to determine the detection of other potential serotypes of BTV in the Peruvian Amazon in order to improve the control strategies of the disease.Item Determinación de Periodos Fisiológicos en la Maduración y Calidad del Aceite de Piñón Blanco Jatropha curcas L.(2012-02) Garay, Richer; Hidalgo, Edison; Alegría Saavedra, Jhonny Alejandro; Mendieta Taboada, Oscar W.El objetivo de este trabajo fue determinar el momento óptimo de cosecha de los frutos y los parámetros de calidad del aceite de piñón blanco (Jatropha curcas L), adecuados para la producción de biodiesel. El trabajo fue desarrollado en la Parcela Experimental El Porvenir del Instituto Nacional de Innovación Agraria del Perú. Se evaluó las características físicas de los frutos y de las semillas y las características químicas del aceite. Los frutos de piñón utilizados fueron seleccionados al inicio del fructificación. El estado de maduración R2 tuvo una duración de 29 ±1.8 horas, el estado R3 de 12 ± 1.6 horas, el estado R4 27 ± 1.7 horas y finalmente R5 de 24 ± 1.0 horas. El análisis químico mostró que las semillas de piñón contienen en el estado fisiológico R4 un 51.5% de grasa, mientras que el índice de acidez más elevado se encontró en el R6 con 3.01 mgKOH/g aceite. Los frutos de piñón se pueden cosechar en los estados fisiológicos R3, R4 y R5 por contar con elevado contenido de aceite y bajo índice de acidez.Item DNA Barcoding of Stingless Bees (Hymenoptera: Meliponini) in Northern Peruvian Forests: A Plea for Integrative Taxonomy(2022-08) Marilena Marconi; Alessandro Modesti; Leydi Paz Alvarez; Paolo Villegas Ogoña; Agustín Cerna Mendoza; Carlos Daniel Vecco Giove; Javier Ormeño Luna; Andrea Di Giulio; Emiliano ManciniStingless bees (Hymenoptera: Meliponini) are among the most important pollinators of tropical forests. Peru is considered a hotspot of biodiversity of Meliponini, but many areas of this country (e.g., Peruvian Amazon) remain unexplored. We aimed to produce a first inventory of stingless bee species dwelling in humid and seasonally dry forests of northern Peru by combining traditional (morphologically-based) taxonomy and DNA barcoding. Specimens were collected in 2020 at five sites located in San Martin and Piura regions. We identified 12 genera of Meliponini. Among those, Trigona and Plebeia were the most abundant (45.9% and 12.8% respectively), whereas Nannotrigona and Scaura were the least represented ones (2.3%). We assigned a reliable species identification to about 30% of specimens (Trigona amazonensis, T. muzoensis, T. williana, Partamona testacea, Scaura tenuis, Tetragona goettei, and Tetragonisca angustula). Yet, more than a half of the specimens received a provisional identification (e.g., Geotrigona cf. fulvohirta, T. cf. amalthea, T. cf. fuscipennis, T. cf. hypogea, Melipona cf. cramptoni, Partamona cf. epiphytophila, Ptilotrigona cf. perenae, Scaura cf. latitarsis, Tetragona cf. clavipes, Trigonisca cf. atomaria). We also highlighted an extensive polyphyly that affected a number of currently recognized species (e.g., T. fulviventris, T. guianae, Plebeia franki, P. frontalis, M. eburnea, M. illota), whose members were split into various clades. Finally, 16% of individuals failed to be identified at the species level (Trigona sp. 1, T. sp. 2, Nannotrigona sp., Partamona sp., Scaptotrigona sp. 1, S. sp. 2, Trigonisca sp. 1, and Trigonisca sp. 2). We discuss our findings according to the current faunistic and biogeographic knowledge of Meliponini in Peru and the Neotropical region. We also remark on the importance of conducting a taxonomic revision of stingless bees and improving both their morphology-based identification keys and BOLD repository. Finally, we claim that integrative taxonomy shall be strongly implemented to truly assess the biodiversity of Neotropical stingless bees, allowing conserving these important pollinators and the associated traditional meliponiculture in an effective manner.Item Efectividad de las vitaminas C y E como tratamiento adyuvante a la terapia triple estándar para Helicobacter pylori en una cohorte de la Amazonía peruana(2019-10) Cubas Llalle, Wildor Samir; Reyes Cahuila, Rómulo; Arévalo Ramírez, Heriberto; Quispe, Antonio M.Introducción y objetivos: la terapia con vitaminas C y E ha sido propuesta como adyuvante a la terapia triple estándar (TTE) con el fin de incrementar la tasa de erradicación del Helicobacter pylori (H. pylori). En este estudio probamos esta hipótesis en una cohorte de pacientes de la Amazonía peruana. Materiales y métodos: retrospectivamente, evaluamos una cohorte de 50 pacientes infectados con H. pylori del Hospital de Tarapoto en el período comprendido entre julio-diciembre de 2016; de estos, 25 fueron tratados con TTE (amoxicilina 1 g, claritromicina 500 mg y omeprazol 20 mg, dos veces al día por 14 días) en adyuvancia con las vitaminas C y E, y 25 fueron tomados al azar (1:1), quienes solo recibieron TTE. Se estimó y comparó la efectividad de ambos tratamientos utilizando un modelo regresión general lineal con familia Poisson y link log, teniendo como desenlace de interés la erradicación del H. pylori confirmada por histopatología. Resultados: al comparar la cohorte de expuestos y con los no expuestos, no se encontraron diferencias significativas en sus características basales, incluyendo edad (38 ± 11 frente a 36 ± 10 años), género masculino (65% frente a 63%), síntomas y diagnóstico histopatológico. Al comparar la efectividad de ambos tratamientos, se encontró un incrementó no significativo en las tasas de erradicación del 9,5% (91% frente a 82%, razón de tasas de incidencia = 1,11; intervalo de confianza [IC] 95%: 0,92 a 1,36). Conclusiones: la terapia adyuvante con vitaminas C y E podría ayudar a incrementar la efectividad de la TTE para H. pylori en pacientes de la Amazonía peruana, aunque se requiere confirmar esta hipótesis en un ensayo clínico.Item Efecto de la suplementación de bloques multinutricionales con residuos agroindustriales en la producción y calidad de leche de vacas criollas al pastoreo en San Martín, Perú(2020-11) Godoy Padilla, David; Puemape Dávila, Fredy Rolan; Roque Alcarraz, Roberto Edgardo; Fernández Curi, Melisa; Vargas Morán, Jorge; Gamarra Carrillo, Segundo; Hidalgo Lozano, Víctor; Gómez Bravo, CarlosSe evaluó el efecto de bloques multinutricionales (BMN) a base de residuos agroindustriales sobre la producción y composición de la leche de vacunos en una región tropical del Perú. Para la elaboración de los BMN, se usaron residuos agroindustriales del procesamiento del arroz (arrocillo y polvillo) y del coco (torta). Se utilizaron 12 vacas criollas al pastoreo en potreros con Brachiaria brizantha distribuidas en 2 grupos (A y B) de seis animales durante dos periodos de 21 días cada uno. Se establecieron dos tratamientos: T0 (pastoreo sin suplementación) y T1 (pastoreo más suplementación con BMN). Durante el primer periodo, el grupo A recibió el T1 y el grupo B, el T0, mientras que en el segundo periodo se hizo a la inversa. Se midió la producción lechera diaria (kg/día), la composición de la leche (proteína, grasa, lactosa, sólidos totales, %) y el nivel de urea en leche (mg/100 ml). Se utilizó el diseño experimental de cambio simple para analizar los resultados (α=0.05). No hubo diferencias significativas en la producción de leche entre tratamientos (T0: 4.0 kg/día; T1: 4.1 kg/día). En la composición de la leche, el nivel de proteína y lactosa fueron significativamente superiores en T1 que en T0 (p<0.05), pero similares con respecto a urea en leche y sólidos totales. El bajo consumo de BMN (346 g/día/vaca) puede explicar la falta de respuesta a la suplementación.Item Effect of teaching leadership styles on the prevention of adolescence pregnancy: a case study conducted at Universidad César Vallejo, Peru [version 1; peer review: awaiting peer review](2021-03) Delgado Bardales, José Manuel; Rubio Luna Victoria, Edward Freddy; Valera Vega, Orfelina; Contreras Julián, Rosa Mabel; Palomino Alvarado, Gabriela del Pilar; Sánchez Dávila, Keller; Rodriguez Espejo, Yoni Meni; Lowy, Daniel A.Background: In this study we aimed to determine the effect of university teaching and leadership styles at Universidad César Vallejo on the prevention of adolescence pregnancy. Methods: We performed a non-experimental, quantitative, crosssectional study, with a correlational descriptive design using a survey. Participants were students in classes enrolled in the starting two semesters at Universidad César Vallejo, Peru. The questionnaire comprised three sections: (I) General demographic data, (II) Teacher leadership styles, and (III) Pregnancy prevention teachings. Results: According to the students (n=793), teaching leadership styles are of three types: Laissez faire, transactional, and transformational. Types of pregnancy prevention from the students’ standpoint are the following: "high" level of "primary prevention" (44.4%), "medium" level of "tertiary prevention" (36.6%), and "high" level of "secondary prevention" (36.2%). Chi-Square test revealed that the three styles of leadership significantly affect the prevention of pregnancy: transformational (X2 = 136.390), transactional (X2 = 95.539), and Laissez Faire (X2 = 80.557) (p <0.05). Overall, there is a significant impact of university teaching leadership on pregnancy prevention among higher education students (X2 = 110,634, p = 0.0000), with a significance level of 5%. Conclusions: It can be concluded that for college students, teaching leadership style significantly affects the prevention of adolescent pregnancy.Item Environmental, geographical and time-related impacts on avian malaria infections in native and introduced populations of house sparrows (Passer domesticus), a globally invasive species(2023-03) Ferraguti, Martina; Ferraguti, Martina; Jiménez-Peñuela, Jéssica; Martínez-de la Puente, Josué; Garcia-Longoria, Luz; Figuerola, Jordi; Muriel, Jaime; Albayrak, Tamer; Bensch, Staffan; Bonneaud, Camille; Clarke, Rohan H.; Czirják, Gábor Á.; Dimitrov, Dimitar; Espinoza, Kathya; Ewen, John G.; Ishtiaq, Farah; Flores-Saavedra, Wendy; Garamszegi, László Zsolt; Hellgren, Olof; Horakova, Dita; Huyvaert, Kathryn P.; Jensen, Henrik; Križanauskienė, Asta; Lima, Marcos R.; Lujan-Vega, Charlene; Magnussen, Eyðfinn; Martin, Lynn B.; Matson, Kevin D.; Møller, Anders Pape; Munclinger, Pavel; Palinauskas, Vaidas; Pap, Péter L.; Pérez-Tris, Javier; Renner, Swen C.; Ricklefs, Robert; Scebba, Sergio; Sehgal, Ravinder N. M.; Soler, Manuel; Szöllősi, Eszter; Valkiūnas, Gediminas; Westerdahl, Helena; Zehtindjiev, Pavel; Marzal, AlfonsoAim: The increasing spread of vector-borne diseases has resulted in severe health concerns for humans, domestic animals and wildlife, with changes in land use and the introduction of invasive species being among the main possible causes for this increase. We explored several ecological drivers potentially affecting the local prevalence and richness of avian malaria parasite lineages in native and introduced house sparrows (Passer domesticus) populations. Location: Global. Time period: 2002–2019. Major taxa studied: Avian Plasmodium parasites in house sparrows. Methods: We analysed data from 2,220 samples from 69 localities across all continents, except Antarctica. The influence of environment (urbanization index and human density), geography (altitude, latitude, hemisphere) and time (bird breeding season and years since introduction) were analysed using generalized additive mixed models (GAMMs) and random forests. Results: Overall, 670 sparrows (30.2%) were infected with 22 Plasmodium lineages. In native populations, parasite prevalence was positively related to urbanization index, with the highest prevalence values in areas with intermediate urbanization levels. Likewise, in introduced populations, prevalence was positively associated with urbanization index; however, higher infection occurred in areas with either extreme high or low levels of urbanization. In introduced populations, the number of parasite lineages increased with altitude and with the years elapsed since the establishment of sparrows in a new locality. Here, after a decline in the number of parasite lineages in the first 30 years, an increase from 40 years onwards was detected. Main conclusions: Urbanization was related to parasite prevalence in both native and introduced bird populations. In invaded areas, altitude and time since bird introduction were related to the number of Plasmodium lineages found to be infecting sparrows.Item Estrategias didácticas de educación física para mejorar el rendimiento académico de estudiantes universitarios con base en gimnasia cerebral de Paul Dennison(2021-10) Ramirez Ramirez, Wildoro; Palacios Paredes, Wendy LillyEste trabajo estudia la influencia de las estrategias de enseñanza de la educación física basadas en los ejercicios de gimnasia cerebral de Paul Dennison en el rendimiento académico de los estudiantes universitarios del primer ciclo de la Facultad de Ciencias Económicas de la Universidad Nacional Mayor de San Martín del Perú. La muestra estuvo conformada por 120 estudiantes, y se escogió probabilísticamente en una muestra estratificada y se conformaron dos grupos, un grupo Control con 68 estudiantes y un grupo Experimental con 52 estudiantes. Originalmente se estudió la homogeneidad de las notas de los alumnos de 4º y 5º de secundaria en Matemáticas y Comunicación mediante análisis de normalidad y prueba U de Mann-Whitney. Luego, el grupo Experimental fue intervenido mediante ejercicios de educación física basados en gimnasia cerebral durante todo el ciclo académico, quedando el Grupo Control sin intervención. Al final del ciclo se recogieron los puntajes de Matemáticas y Comunicación de ambos grupos y se analizaron estadísticamente mediante el Utest de Mann-Whitney para establecer las diferencias entre los grupos y la influencia de la intervención, con significación á = 0,05. Se demostró que hubo diferencia estadísticamente significativa entre los puntajes de los dos grupos de estudio (p-valor < 0,05) con un nivel de confianza del 95%, con puntajes más altos en el grupo experimental, atribuidos a la intervención realizada. © Federación Española de Asociaciones de Docentes de Educación Física (FEADEF) Se demostró que hubo diferencia estadísticamente significativa entre los puntajes de los dos grupos de estudio (p-valor < 0,05) con un nivel de confianza del 95%, con puntajes más altos en el grupo experimental, atribuidos a la intervención realizada. © Federación Española de Asociaciones de Docentes de Educación Física (FEADEF) Se demostró que hubo diferencia estadísticamente significativa entre los puntajes de los dos grupos de estudio (p-valor < 0,05) con un nivel de confianza del 95%, con puntajes más altos en el grupo experimental, atribuidos a la intervención realizada.
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