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Although the coffee berry borer (CBB) is the most important coffee pest worldwide, controversies remain regarding basic aspects of its behavior, such as how this is influenced by abiotic factors of the coffee agroecosystem. In this study, we compared the level of infestation and total population per fruit under three different levels of shade (full sun, up to 40%, and >40%), for two varieties of coffee (Caturra and Catimor) and at two different altitudes (1200 to 1700 m above sea level) in Rodríguez de Mendoza, Peru. We found that the infestation percentage increases with the shade levels of the plot. The average percentages of infestation according to shade levels were 10.52% for coffee in full sun, 12.56% with up to 40% shade, and 17.99% for coffee growing in more than 40% shade; however, maximum infestation values of 68.421%, 84.127%, and 95.238% were obtained for coffee plantations in full sun, up to 40% shade, and more than 40% shade, respectively. The Catimor variety was found to be more susceptible to CBB infestation than Caturra. In addition, CBB infestation per fruit was found to decrease with increasing altitude.

El cultivo de anteras es una herramienta que permite la producción de plantas homocigotas doble haploides y es una alternativa viable y apropiada para el mejoramiento de cultivos. Sin embargo, el éxito de su aplicación depende de diversos factores que afectan su eficiencia. Por ello, el objetivo del estudio fue determinar los estadios de las microsporas asociadas con el desarrollo de los botones florales, así como evaluar los métodos de esterilización y el desarrollo de las anteras de Physalis peruviana en cuatro medios de cultivo. El estadio uninucleado tardío, adecuado para iniciar la androgénesis se encontró en botones florares de entre 7,85 y 9,37 mm de longitud polar. Los niveles más bajos de oxidación (10 %) y contaminación (20 %), y la mayor viabilidad de anteras (70 %) se registraron bajo el tratamiento de esterilización superficial con etanol (70 %) por 3 min y NaClO (2 %) durante 15 min. La formación de callos y la regeneración de la planta se obtuvieron en los medios de cultivo B5 y LS, lo que indica su utilidad en los programas de mejoramiento.

El cadmio es un metal que afectan los recursos naturales, plantas y seres humanos. Ante ello, se ha buscado diferentes métodos para mitigar el problema, uno de ellos es la fitorremediación que hace uso de especies que tienen el potencial de acumular el metal pesado en sus tejidos vegetales. Esta investigación tuvo por objetivo evaluar el efecto que causa la toxicidad de cadmio en la morfología de plantas de cadillo (Bindes pilosa L.). Las plantas fueron sembradas en dos tipos de sustrato con pH 6.27 y 5.53, agregando diferentes concentraciones de cloruro de cadmio (CdCl2) (0, 5 y 10 ppm) dentro de un invernadero; donde se tuvo 6 tratamientos con 5 repeticiones, teniendo así 30 unidades experimentales. Se evaluó parámetros morfológicos y concentraciones de Cd en la parte radicular y foliar. De los resultados obtenidos, el cadillo sembrado en el sustrato con pH 5.53 sin CdCl2 tuvo mayor altura con 27.18 cm, con el mismo sustrato más 10 ppm de CdCl2 se obtuvo mayores valores en las variables; número de brotes (16 brotes), peso fresco foliar (26.70 g), peso seco foliar (10.92 g), peso fresco radicular (5.77 g), peso seco radicular (1.04 g) y longitud de raíz (26.90 mm). Respecto a la acumulación de Cd en los tejidos vegetales se obtuvo mayor concentración en la parte foliar (7.27 ppm) y menos en la raíz (2.57 ppm). Se concluye, que esta especie podría tener utilidad en la fitorremediación de suelos contaminados con Cd.

Lilies are one of the most important, beautiful, and economically valuable flowers in the world. Lilium is regarded as a popular floral trade cut flower, so viable protocols are needed to provide seed production, multiplication, and preservation. In vitro protocols allow for rapid large-scale production and rejuvenation of planting material, but to be a commercially viable multiplication method, the procedure must allow for rapid production of viable, true-to-type plants quickly. The objective was to evaluate the in vitro production of microbulbs of five lily varieties (Lilium “Champion Diamond,” Lilium “Yellow Diamond,” Lilium “Batavus,” Lilium “Hyde Park,” and Lilium sp.) using different concentrations of 6-benzylaminopurine (0, 0.5, 1.0, 1.5, 1.5, and 2.0 mg L−1 BAP) and to determine the commercial quality (flowering) of the plants grown from the seed obtained. Results from the micropropagation phase show Lilium “Batavus” and Lilium “Hyde Park” varieties had better in vitro responses, especially when grown with 1.0 and 1.5 mg L−1 BAP, respectively. Plants (of all varieties) grown from microbulbs showed positive growth and generally resulted in commercially viable flower production. Finally, the results of this study support the use of bulb scales as an alternative for obtaining vegetative seeds with high potential for lily cultivation.

BACKGROUND: Blueberry production has generated great commercial expectations, therefore for its agricultural expansion it is necessary to overcome the challenges at the time of mass propagation. OBJECTIVE: Evaluate the effect of a set of factors influencing micropropagation, as well as the influence of substrates on the ex vitro morpho-physiological performance of blueberry seedlings. METHODS: A set of protocols were developed to optimize all stages of micropropagation (aseptic establishment, multiplication, rooting, and acclimatization) of blueberries. RESULTS: Explants immersed in 1.5% NaClO for 8 min and then in 0.1% HgCl2 for 2 min achieved 100% sterility and a viability rate of 86.67% for ‘Biloxi’ and 93.33% for ‘Bluecrop’. At the multiplication stage, the maximum number of shoots of ‘Biloxi’ (3.53) and ‘Bluecrop’ (2.27) were obtained on the medium supplemented with 0.2 and 10 mg L–1 silver nanoparticles (AgNPs), respectively. The percentage of in vitro rooting was significantly improved on media containing activated charcoal, with levels between 80% and 100%. In the acclimatization phase, plants grown in a substrate composed of peat and cocomix® (2:1 ratio) showed greater uniformity and better morpho-physiological behavior. CONCLUSIONS: The present results could be successfully used for large-scale commercial production of blueberries of the varieties ‘Biloxi’ and ‘Bluecrop’.

Los sistemas silvopastoriles (SSP) son una alternativa para la producción ganadera sostenible. Por este motivo, el presente estudio se desarrolló con el objetivo de evaluar parámetros productivos y nutricionales del componente forrajero (CF) en distintos arreglos silvopastoriles con Alnus acuminata y su comparación con sistemas a campo abierto. Se estableció un diseño de bloques completos al azar, para lo cual, fueron seleccionadas 16 parcelas con características de homogeneidad en edad y tipo de CF. Se evaluó la composición florística, clasificación funcional de las especies herbáceas, biomasa, materia seca y composición nutricional. Los resultados obtenidos registraron la presencia de 22 especies, predominando la familia Poaceae (8 especies), asimismo se encontró que los arreglos silvopastoriles presentan el mayor porcentaje de especies deseables, situación contraria a lo ocurrido en los sistemas a campo abierto. Por otro lado, los parámetros productivos y nutricionales, mostraron diferencias significativas (P

The evaluation of suitable landfill sites is a complex process and requires various legislative, technical, social, and environmental criteria. Therefore, this study provides a management tool for identifying suitable sites for landfills through the integrated use of the analytic hierarchy process (AHP), geographic information systems (GISs), and remote sensing (RS). Accordingly, fourteen subcriteria were identified and grouped into physical (7), environmental (3), and socioeconomic (4) criteria and were weighed using pairwise comparison matrices (PCMs). The weighted linear combination (WLC) approach of maps allowed us to generate models and submodels of land suitability. From the territory of the districts of Chachapoyas and Huancas, 0.9% (1.71 km2), 71.1% (141.89 km2), 21.0% (41.86 km2), 0.0%, and 7.7% (14.21 km2) have highly suitable, moderately suitable, marginally suitable, unsuitable, and restricted conditions, respectively, for a landfill site. Twelve highly suitable sites were identified, of which three were selected based on their shape and the minimum area required for the operation of the landfill until 2040. In fact, this study proposes a management tool for decision-makers (DMs) that improve the process of selecting landfill sites, supported by engineering and its applications for territorial sustainability.

El objetivo del presente estudio fue evaluar el establecimiento, crecimiento, rendimiento y valor nutritivo de cinco especies nativas con valor forrajero (Cenchrus clandestinus, Philoglossa mimuloides, Philoglossa sp., Trifolium dubium y Trifolium repens). El experimento se realizó en el distrito de Molinopampa (Perú), donde se instalaron parcelas de 30 m2. La altura de planta se midió mensualmente hasta los 90 días. El material se cortó a nivel del suelo, se pesó, se secó y se determinaron los rendimientos de forraje verde y materia seca. El valor nutricional de las muestras se realizó siguiendo el procesamiento de la AOAC. Los resultados muestran que el porcentaje de establecimiento más alto fue alcanzado por T. repens (89,51%). La altura de planta mostró que P. mimuloides y Philoglossa sp. registraron su mayor crecimiento entre los días 30 y 60 después del establecimiento; y además fueron las especies con mayores niveles forraje verde (7,46 y 8,04 kg/m2) y materia seca (8,58 y 8,90 t/ha). En términos de valor nutricional, T. dubium y C. clandestinus registraron los niveles más altos de proteína y fibra, respectivamente; mientras que las especies del género Philoglossa tienen mayor digestibilidad.

El aroma del cacao criollo (Theobroma cacao) fino de aroma se define por compuestos volátiles como las pirazinas, cetonas y los aldehídos, que se forman durante el tostado del grano, a partir de los precursores del aroma (azúcares reductores y aminoácidos libres) que se generan en el interior del grano a través de reacciones enzimáticas durante la fermentación; por esta razón la fermentación es el proceso más importante de la cadena de valor. Esta investigación analizó la producción de precursores del aroma y los compuestos aromáticos volátiles del cacao en muestras fermentadas secas y tostadas comparadas con muestras fermentadas, secas y sin tostar, utilizando la tecnología de cromatografía de gases acoplada a un detector de masas con micro extracción en fase sólida (GC-MS-SPME-HS), se identificaron 80 compuestos volátiles de las familias de aldehídos, cetonas, alcoholes, ésteres, ácidos y pirazinas. En conclusión, se logró identificar los compuestos volátiles del cacao criollo fino de aroma de la provincia de Utcubamba–Cajaruro; los cuales se generan con el proceso de fermentación y tostado del cacao que caracterizan a las muestras de la región por contener elevadas propiedades especiales, funcionales y sensoriales agradables.

Edaphic macrofauna is a biological soil indicator that is rarely applied in the identification of soil quality in coffee farms. The objective was to evaluate edaphic macrofauna and soil physico-chemical properties in four coffee farms at different altitudes. The farms were selected in four hamlets of small-scale coffee farmers. In one-hectare plantations, three monoliths of 25 × 25 cm wide by 30 cm depth were sampled. Soil samples were taken from each plot, then the organic matter (OM) content, hydrogen potential (pH), electrical conductivity (EC) and nitrogen (N) content were determined. There were no differences in macrofaunal diversity for the altitudes studied, but there were differences according to the time of year (rainfall and low water). The maximum Shannon index was 2.2 (rainy season) and 1.1 (dry season). Physico-chemical parameters such as soil pH ranged from 7.8 - 8.15 in the lower altitude farms and for the higher altitude farms it was 6.38 - 6.65. Soil pH was highly negatively correlated with altitude. Nitrogen was positively correlated with organic matter. Faunal diversity is negatively correlated with season and the presence of microorganisms is influenced by the physico-chemical characteristics of the soil.

La preocupación por el contenido de cadmio en los suelos de áreas productoras de cultivos va en aumento en los últimos años. En la presente investigación, se evaluó la concentración de Cadmio en el sistema suelo, hoja y fruto en fincas cafetales bajo dos sistemas de producción, orgánica y convencional en el distrito de Omia, región Amazonas, Perú. Se muestrearon suelos, hojas y frutos y se midió la concentración de cadmio mediante la técnica de espectrofotometría, luego se realizó las comparaciones de mediante un análisis de varianza; además se caracterizaron los suelos según sus características de pH, materia orgánica y conductividad eléctrica para posteriormente realizar una correlación de Pearson. Como resultado se obtuvo que la concentración de cadmio en el sistema suelo, hoja y fruto, no superan los Límites Máximos Permisibles (LMP) estipulados por el Ministerio del Ambiente del Perú, obteniendo mayores valores en el suelo con 0,72 mg kg-1, mientras que menores valores se encontró en frutos con 0,1 mg kg-1. Comparado la concentración en dos sistemas de producción, se observa que tanto en suelo como en hojas la mayor concentración está en el sistema orgánico, mientras que en frutos la mayor concentración está en el sistema convencional. Además, se evidencia correlación significativa y positiva entre el contenido de cadmio de los suelos y características fisicoquímicas de estos como pH y porcentaje materia orgánica. En conclusión, los resultados obtenidos no sobrepasan los LPM, por lo que la concentración de cadmio en este cultivo no se considera como un problema.

espanolEl arbol de la quina (Cinchona officinalis), especie emblematica de Peru, durante muchos anos ha venido siendo amenazado de desaparecer. El objetivo de este estudio fue evaluar la influencia del tipo de mini-estaca (apical y basal) y el tiempo de absorcion de acido indolbutirico (0, 2, 6 y 10 minutos) sobre la multiplicacion clonal del arbol de la quina. Los brotes fueron colectados de arboles de poblaciones naturales presentes en el bosque montano Conila-Peru, a una altitud de 2800 m. Las mini-estacas, basales y apicales, se trataron con acido indolbutirico a 2000 mg·L -1 y se dejaron inmersas por distintos tiempos. Los datos se sometieron a un analisis de varianza y las medias se compararon con la prueba Tukey. Luego de 60 dias se encontro que las miniestacas basales presentaron un porcentaje de enraizamiento significativamente superior (54,77 %) respecto a las mini-estacas apicales (40,10 %), siendo superior tambien en sobrevivencia (62,75 %) y tamano de raices (17,38 mm). Los tiempos de 6 y 10 minutos de absorcion fueron los mas sobresalientes, mientras que el control (0 minutos) resulto ser el tratamiento mas bajo. En conclusion, el uso de mini-estacas basales y tiempos de absorcion de 6 y 10 minutos son las mejores condiciones para garantizar el enraizamiento de las mini-estacas del arbol de la quina. EnglishThe cinchona tree (Cinchona officinalis), an emblematic species of Peru, has for many years been threatened with extinction. The objective of this study was to evaluate the influence of the type of mini-stake (apical and basal) and the absorption time of indolebutyric acid (0, 2, 6, and 10 minutes) on the clonal multiplication of the cinchona tree. The shoots were collected from trees of natural populations present in the Conila-Peru montane forest, at an altitude of 2800 m. The mini-cuttings, basal and apical, were treated with indole butyric acid at 2000 mg·L -1 and were left to rest for different times. The data were subjected to an analysis of variance and the means were compared with the Tukey test. After 60 days, it was found that the basal mini-cuttings presented a significantly higher rooting percentage (54.77 %) compared to the apical mini-cuttings (40.10 %), being also higher in survival (62.75 %) and size of roots (17.38 mm). The absorption times of 6 and 10 minutes turned out to be the most outstanding, while the control (0 minutes) turned out to be the lowest treatment. In conclusion, the basal mini-cuttings and the absorption times of 6 and 10 minutes turn out to be the most appropriate to guarantee the rooting of mini-cuttings of the cinchona tree.

The phenotypic characterization of cacao (Theobroma cacao L.) plays an important role in the generation of information for the conservation of cacao germplasm. The objective of this study is to characterize phenotypically 146 ecotypes of fine-aroma native cacao (FFNC) from northeastern Peru that were collected from 280 to 1265 metres above sea level. Morphological descriptors of fruits and seeds, sensory characteristics, and productivity descriptors were used. The data obtained were analyzed using descriptive statistics with pie charts, distribution histograms, and multiple correspondence analysis. The results showed that 76.7% of the cocoa ecotypes had green immature fruits, 73% showed slight roughness on the surface of the fruit, 54% showed an intermediate thickness of the fruit wall, and 90% had the appearance of pairs of equidistant ridges. Regarding seed characteristics, 71% showed purplish cotyledons, with a high presence of floral and fruity notes and low levels of bitterness and astringency. Likewise, 52% of the fruits and 64% of the seeds were long. More importantly, cocoa beans needed to produce between 14 and 16 pods to obtain one kilogram of dry cocoa, which reflects a good level of productivity. Finally, there was a positive relationship between elevation levels and the presence of fine-flavoured native cocoa, i.e., the greatest diversity of native cocoa with floral and fruity notes was found above 501 metres above sea level. The authors thank the Fondo Nacional de Desarrollo Cientifico, Tecnologico y de Innovacion Tecnologica (FONDECYT) for funding this research through the contract No 026-2016 of the Circulo de Investigacion para la Innovacion y el fortalecimiento de la cadena de valor del cacao nativo fino de aroma en la zona nor oriental del Peru-CINCACAO project, executed by the Instituto de Investigacion para el Desarrollo Sustentable de Ceja de Selva (INDES-CES).

Lakes are water bodies that play an essential role as water sources for humanity, as they provide a wide range of ecosystem services. Therefore, this study aimed to evaluate Lake Pomacochas, a high Andean lake in the north of Peru. A variety of parameters were studied, including physicochemical parameters such as temperature (T°C), dissolved oxygen (DO), potential hydrogen (pH), electrical conductivity (EC), turbidity, total dissolved solids (TDS), biochemical oxygen demand (BOD), alkalinity, and chlorides hardness; the concentrations of nitrates, nitrites, sulfates, and ammonium; elements such as aluminum (Al), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), and boron (B); as well as metals and metalloids such as zinc (Zn), cadmium (Cd), copper (Cu), lead (Pb), and arsenic (As). In addition, pH, Zn, and Cu were evaluated at the sediment level. It is important to note that all parameters evaluated in the water matrix showed significant differences in the seasonal period and depth levels. In comparison, the parameters evaluated at the sediment level had no significant differences between the seasonal period and sampling points. As for the seasonal period, the variables that were higher for the dry season were electrical conductivity, total dissolved solids, and lead while that for the wet season were biochemical oxygen demand, zinc, magnesium, turbidity, calcium, dissolved oxygen, temperature, and potential hydrogen. At the depth levels, parameters such as total dissolved solids, lead, and arsenic had similar behavior for the three depths evaluated. According to national standards, latent contamination by cadmium and lead was found in the lake water from the ecological risk assessment. However, by international standards, all sampling stations showed a high level of contamination by cadmium, lead, zinc, copper, and arsenic, which represents a potential risk for the development of socioeconomic activities in the lake. At the same time, the evaluation of sediments did not present any potential risk.

Cacao plant cadmium accumulation has become a major concern, especially for small Amazonian producers. A sustainable alternative to address its toxicity is the use of cadmium removal bacteria. In this regard, 138 rhizosphere isolates from cacao were examined. Supported by their phenotypic characterization and in vitro cadmium tolerance, three hypertolerant bacteria were selected and identified as members of the

Cacao (Theobroma cacao L.) is the basis of the lucrative confectionery industry with “fine or flavour” cocoa attracting higher prices due to desired sensory and quality profiles. The Amazonas Region (north Peru) has a designation of origin, Fine Aroma Cacao, based on sensory quality, productivity and morphological descriptors but its genetic structure and ancestry is underexplored. We genotyped 143 Fine Aroma Cacao trees from northern Peru (Bagua, Condorcanqui, Jaén, Mariscal Cáceres, and Utcubamba; mainly Amazonas Region), using 192 single nucleotide polymorphic markers. Identity, group, principal coordinate, phylogenetic and ancestry analyses were conducted. There were nine pairs of matched trees giving 134 unique samples. The only match within 1,838 reference cacao profiles was to a putative CCN 51 by a Condorcanqui sample. The “Peru Uniques” group was closest to Nacional and Amelonado-Nacional genetic clusters based on FST analysis. The provinces of Bagua and Utcubamba were genetically identical (Dest = 0.001; P = 0.285) but differed from Condorcanqui (Dest = 0.016–0.026; P = 0.001–0.006). Sixty-five (49%) and 39 (29%) of the Peru Uniques were mixed from three and four genetic clusters, respectively. There was a common and strong Nacional background with 104 individuals having at least 30% Nacional ancestry. The fine aroma of cacao from Northern Peru is likely due to the prevalent Nacional background with some contribution from Criollo. A core set of 53 trees was identified. These findings are used to support the continuance of the fine or flavour industry in Peru.

The hyperdiverse genus Trichoderma is one of most useful groups of microbes for a number of human activities, and their accurate identification is crucial. The structural simplicity and lack of distinctive phenotypic variation in this group enable the use of DNA-based species delimitation methods in combination with phylogenies (and morphology when feasible) to establish well-supported boundaries among species. Our study employed a multilocus phylogeny and four DNA-based methods (automated barcode gap discovery [ABGD], statistical parsimony [SPN], generalized mixed Yule coalescent [GMYC], and Bayesian phylogenetics and phylogeography [BPP]) for four molecular markers (acl1, act, rpb2, and tef1) to delimit species of two lineages of Trichoderma. Although incongruence among these methods was observed in our analyses, the genetic distance (ABGD) and coalescence (BPP) methods and the multilocus phylogeny strongly supported and confirmed recognition of 108 and 39 different species in the Harzianum and Longibrachiatum lineages, including three new species associated with cacao farms in northern Peru, namely, T.awajun, sp. nov., T. jaklitschii, sp. nov., and T. peruvianum, sp. nov. Morphological distinctions between the new species and their close relatives are primarily related to growth rates, colony appearance, and size of phialides and conidia. This study confirmed that an integrative approach (DNA-based methods, multilocus phylogeny, and phenotype) is more likely to reliably verify supported species boundaries in Trichoderma.

La deficiencia hídrica es una de las principales limitaciones para la producción de frijol común en el mundo. En ese sentido, el objetivo de este estudio fue determinar la respuesta fisiológica y morfológica de cinco genotipos de frijol (INDES-01, INDES-02, INDES-03, INDES-04, INDES-05) sometidos a diferentes frecuencias de déficit hídrico (intervalos de riego de 0, 5, 10 y 15 días). Para ello, se utilizó un diseño completamente al azar con arreglo factorial, con plantas cultivadas en recipientes individuales por un periodo de 90 días. Los resultados mostraron que las condiciones de déficit hídrico afectaron el índice de clorofila, área foliar, longitud de raíz y materia seca. Asimismo, se observó que el efecto del estrés hídrico, en cuanto a magnitud, depende de los genotipos y su nivel de tolerancia al estrés hídrico.

In this work, we have developed a new kind of nanocolumnar birefringent Bragg microcavity (BBM) that, tailored by oblique angle deposition, behaves as a selective transducer of volatile organic compounds (VOCs). Unlike the atomic lattice origin of birefringence in anisotropic single crystals, in the BBM, it stems from an anisotropic self-organization at the nanoscale of the voids and structural elements of the layers. The optical adsorption isotherms recorded upon exposure of these nanostructured systems to water vapor and VOCs have revealed a rich yet unexplored phenomenology linked to their optical activity that provides both capacity for vapor identification and partial pressure determination. This photonic response has been reproduced with a theoretical model accounting for the evolution of the form birefringence of the individual layers upon vapor condensation in nanopores and internanocolumnar voids. BBMs that repel water vapor but are accessible to VOCs have been also developed through grafting of their internal surfaces with perfluorooctyltriethoxysilane molecules. These nanostructured photonic systems are proposed for the development of transducers that, operating under environmental conditions, may respond specifically to VOCs without any influence by the degree of humidity of the medium.

The presence of toxic metals such as aluminum is described as a factor that could lead to a significant decrease in crop productivity, particularly for the cultivation of acidophilic plants. In the present study, in vitro cultivation of pineapple was used as a model to evaluate the role of silver nanoparticles (0.005, 0.01, 0.025, 0.05, and 0.1 g L−1 Ag NPs) against the negative effects of aluminum (0, 100, 300, and 500 μM AlCl3). The results showed that the presence of 0.025 g L−1 Ag NPs stimulated a higher concentration of photosynthetic pigments “a”, “b”, “a + b” and carotenoids in treatments with high levels of AlCl3. The application of Ag NPs allowed better shoot formation, improved chlorophyll a/b, and total/carotenoid ratios, as well as better levels of proline biosynthesis in response to stress. The synergistic interaction of Ag NPs and AlCl3 increased the availability and assimilation of mineral elements (K, Ca, Mg, Fe, Cu, Mn, and Zn) while decreasing Al translocation. In conclusion, the implementation and validation of Ag NPs in agricultural fields would be revolutionary because they represent a novel alternative for overcoming the limitations imposed by the presence of Al.

Solid-state dewetting (SSD) on patterned substrates is a straightforward method for fabricating ordered arrays of metallic nanoparticles on surfaces. However, a drawback of this procedure is that the patterning of substrates usually requires time-consuming and expensive two-dimensional (2D) fabrication methods. Nanostructured thin films deposited by oblique angle deposition (OAD) present at the surface a form of stochastically arranged periodic bundles of nanocolumns that might act as a patterned template for fabricating arrays of nanoparticles by SSD. In this work, we explore this concept and investigate the effect of three different types of OAD SiO2 thin films on the SSD of Au deposited on their surface. We demonstrate that the size and spatial distribution of the particles can be tailored through the surface morphology of these OAD film substrates. It has been found that the SSD of the evaporated Au layer gives rise to a bimodal size distribution of particles. A majority of them appeared as mesoparticles with sizes ≳100 nm and the rest as nanoparticles with ∼10 nm, respectively, located either on top of the nanocolumns following their lateral distribution (i.e., resulting from a patterning effect) or incorporated inside the open mesopores existing among them. Moreover, on the SiO2-OAD thin films where interconnected nanocolumnar bundles arrange in the form of discrete motifs, the patterning effect gave rise to the formation of approximately one Au mesoparticle per motif, which is one of the assets of patterned SSD. The morphological, optical (i.e., plasmon resonance), and crystalline structural characteristics of Au mesoparticles suggest that the interplay between a discontinuous nanocolumnar surface acting as a template and the poor adhesion of Au onto SiO2 are key factors for the observed template effect controlling the SSD on the surface of OAD thin films.

espanolEl presente estudio fue realizado en la provincia de Rodriguez de Mendoza en Amazonas (Peru), con el objetivo de caracterizar las unidades agropecuarias cafetaleras (UAC) instaladas en esta region. La poblacion estuvo constituida por 7061 productores, y se calculo un tamano de muestra de 104 productores, a los cuales se les aplico una encuesta debidamente validada y conformada por items vinculados a aspectos tecnicos y socioeconomicos relacionados con la UAC. La informacion recopilada y tabulada fue sometida a la tecnica multivariada de analisis de conglomerados para detectar las variables de mayor incidencia en la diferenciacion de grupos con caracteristicas similares, para esto se utilizo un dendograma como elemento grafico para precisar las variables asociadas a la diferenciacion. Los resultados evidencian la existencia de cinco grupos significativamente diferenciados, que indican a la variedad catimor como la mas cultivada y la presencia de broca y roya del cafe como los problemas fitosanitarios mas importantes. Tambien se observo que la mayoria de las UAC fueron menores a dos hectareas, realizan cultivos bajo sombra y estuvieron vinculadas a la produccion organica, ademas, alcanzaron rendimientos ligeramente superiores al promedio nacional aunque aun se muestra deficiencia en las practicas del cultivo y la comercializacion. EnglishThis study was carried out in the province of Rodriguez de Mendoza in the Amazonas region (Peru), with the objective of characterizing the coffee producing agricultural units (CAU) installed in this region. The population was made up of 7061 producers and a sample size of 104 producers was calculated, to which a duly validated survey was applied, comprised of items linked to technical and socioeconomic aspects related to the CAU. The information gathered and tabulated was subjected to the cluster multivariate analysis technique to detect the variables of greatest incidence in the differentiation of groups with similar characteristics, and a dendrogram was used for this purpose as graphic element to specify the variables associated with the differentiation. The results evidence the existence of five significantly differentiated groups, which indicate the Catimor variety as the most frequently grown and the presence of coffee borer beetle and leaf rust as the most important phytosanitary problems. It was also observed that most of the CAUs were smaller than 2 hectares, they sow crops under shade and were linked to organic production; they also reached slightly higher yields than the national average, although there are still deficiencies in cultivation and commercialization practices.

El desarrollo de la identidad cultural para valorar el patrimonio arqueológico es una temática de gran importancia para los docentes de Historia del Perú. En relación, el objetivo de este estudio fue diseñar estrategias innovadoras para el proceso de Enseñanza – Aprendizaje de la Historia del Perú, utilizando el patrimonio arqueológico de la cultura local Ñañanique, como mediador didáctico que permita el desarrollo de la identidad cultural en estudiantes de Segundo Grado de Educación Media. El enfoque es cuantitativo, el tipo de investigación proyectiva con un diseño de campo transversal. Como resultados más relevantes se consiguió que las estudiantes tienen baja identidad cultural con desconocimiento del patrimonio arqueológico de la cultura Ñañanique, los docentes no utilizan estrategias didácticas para logra un aprendizaje significativo de la Historia. La propuesta quedo estructurada con estrategias didácticas significativas como: trabajo de campo, juego de roles, proyecto de investigación, sociodrama, discusión controversial.

El presente trabajo tuvo por objetivo evaluar la influencia de sustratos en el crecimiento y desarrollo de tomate (Lycopersicum esculentum Mill) cultivado bajo un sistema hidropónico en invernadero. Se instaló bajo un diseño completo al azar (DCA), con cuatro tratamientos: T1 (75% cascarilla de arroz + 25% arena, T2 (75% cascarilla de arroz carbonizada + 25% arena, T3 (75 % Aserrín + 25% arena, T4 (40% cascarilla de arroz carbonizada + 35% aserrín + 25% arena); 8 repeticiones y 32 plantas. Se encontró que el T2, favoreció el incremento de altura (139.13 cm), diámetro de tallo (10.95 mm), número de tomates de primera calidad (15.25) y rendimiento (3.03 kg/planta); no obstante, el T3 y T1 mostraron baja influencia en dichas variables. Se concluye que, el tomate obtiene mayores características morfológicas y fisiológicas en sustrato (cascarilla carbonizada + arena); el aserrín como sustrato no es ideal para su crecimiento y desarrollo.

El estudio tuvo como objetivo analizar la investigación científica y el aprendizaje de los estudiantes de la Escuela de Turismo, Hotelería y Gastronomía en la Universidad Alas Peruanas – Filial Piura. El método se fundamentó en un paradigma positivista bajo un enfoque cuantitativo con un diseño de tipo correlacional, empleando como técnica la encuesta y como instrumento el cuestionario. En general existió una relación directa con una correlación fuerte entre la investigación científica y el aprendizaje en los estudiantes. La experiencia científica constituye un factor importante en el logro de aprendizajes de calidad. Los docentes universitarios deberían desarrollar habilidades investigativas en sus estudiantes. Así se podría ampliar la investigación científica y mejorar la calidad educativa en la educación superior.

Nanostructuration and 2D patterning of thin films are common strategies to fabricate biomimetic surfaces and components for microfluidic, microelectronic or photonic applications. This work presents the fundamentals of a surface nanotechnology procedure for laterally tailoring the nanostructure and crystalline structure of thin films that are plasma deposited onto acoustically excited piezoelectric substrates. Using magnetron sputtering as plasma technique and TiO2 as case example, it is demonstrated that the deposited films depict a sub-millimetre 2D pattern that, characterized by large lateral differences in nanostructure, density (up to 50%), thickness, and physical properties between porous and dense zones, reproduces the wave features distribution of the generated acoustic waves (AW). Simulation modelling of the AW propagation and deposition experiments carried out without plasma and under alternative experimental conditions reveal that patterning is not driven by the collision of ad-species with mechanically excited lattice atoms of the substrate, but emerges from their interaction with plasma sheath ions locally accelerated by the AW-induced electrical polarization field developed at the substrate surface and growing film. The possibilities of the AW activation as a general approach for the tailored control of nanostructure, pattern size, and properties of thin films are demonstrated through the systematic variation of deposition conditions and the adjustment of AW operating parameters. Ministerio de Ciencia e Innovación PID2019-110430GB-C21 Junta de Andalucía P18-RT-3480 European Union 899352

The northeastern region of Peru is one of the centers of origin of cocoa due to the great diversity of this cultivar. The objective of this study is, therefore, to search for different genetic groups of 146 ecotypes of fine-aroma native cacao from the northeastern region of Peru, based on the morphological descriptors of pods, seeds, sensory, yield, and sampling altitude. The data were analyzed using multivariate statistics; a cluster analysis was performed with the numerical and categorical variables, followed by a principal component analysis (PCA) and the DGC (Di Rienzo, Guzmán y Casanoves) mean comparison test for the numerical data. Contingency tables and the multiple correspondence analysis (MCA) were performed for the categorical data. We differentiated 5 genetic groups; helpfully, sensory characteristics of the flowers and pod, size and weight of the seeds, and pod index were in fact crucial in separating the groups. The ecotypes of the groups labeled as “Indes” and “Bagüinos” reported the best sensory characteristics with high floral and fruity notes and with a good yield expressed in pod index (13.88 and 11.88, respectively). Furthermore, these ecotypes are found at medium and high altitudes, above 500 m a.s.l., a factor that enables them to express their sensory and yield attributes. On the contrary, the ecotypes known as “Toribianos” and “Cajas” report the highest pod indices (20.77 and 16.78, respectively), resulting in low productivity. In the future, the variability of the ecotypes found will help establish genetic improvement programs that contribute to the development of cocoa farming in general.

Peru is the ninth exporter of coffee (

Peru is the second largest producer of organic cocoa and one of the most important suppliers of fine aroma cocoa beans in the world (Sánchez et al. 2019). The fine aroma cocoa produced by smallholder farmers in the Bagua and Utcubamba Provinces, Amazonas Department, under the name of "Cacao Amazonas Peru", is protected by the Peruvian appellation rules (Díaz-Valderrama et al. 2020). Despite this importance, native diseases of the crop (

El presente estudio analiza el uso de la rúbrica para desarrollar competencias investigativas en el estudiante de Derecho, la misma que es factible ser aplicada en las asignaturas de metodología de la investigación o tesis. El tema descrito es importante porque permite identificar las competencias investigativas que inciden en el proceso de formación de investigadores universitarios y proyectar la relevancia en el ejercicio profesional que otorgaría competitividad laboral. Se elaboró mediante el paradigma positivista, enfoque cuantitativo, diseño no experimental, tipo descriptivo y método analítico. A través del juicio de expertos y método Delphi se reconoce que la rúbrica holística promovería el pensamiento crítico, cultura científica, consolidación de semilleros de investigación con tendencia multidisciplinaria e interiorización del proceso de formación de investigadores desde las aulas universitarias, al ser una herramienta de autoevaluación. Revisión por pares de doble ciego Campus Piura

La actividad universitaria desarrollada en los entornos virtuales de aprendizaje requiere la aplicación de estrategias destinadas a potencializar la relación docente – estudiante, para lo cual se planteó como objetivo determinar la aceptación del método de casos para promover el pensamiento crítico, desde la perspectiva del docente universitario. La metodología se sustentó en el paradigma positivista, enfoque cuantitativo, diseño no experimental, tipo descriptivo y método analítico. Se aplicó un cuestionario a 43 docentes universitarios encargados de una asignatura adscrita a la carrera profesional de Derecho y con vínculo laboral con universidades de la Región Piura–Perú. Se obtuvo como resultado que el 84% de los participantes consideraron que el pensamiento crítico se promueve a partir de la aplicación del método de casos y que el aprendizaje es más efectivo si los estudiantes construyen o descubren el conocimiento a partir interacción docente-estudiante. Se concluyó que el método de casos es reconocido y aceptado por los docentes en las facultades de Derecho porque incentiva el análisis y reflexión del estudiante, quienes al analizar los hechos deberán plantear una alternativa de solución. Palabras clave: pensamiento crítico, docente virtual, método de casos, competencias. Referencias [1]C. De la Fe Rodríguez, I. Vidaurreta Porrero , Á. Gómez Martín y J. C. Corrales Romero, «El método de estudio de casos: Una herramienta docente válida para la adquisición de competencias,» Revista Electrónica Interuniversitaria de Formación del Profesorado, vol. 18, nº 3, pp. 127-137, 2015. [2]A. Estrada Cuzcano y K. L. Alfaro Mendives, «El método de casos como alternativa pedagógica para la enseñanza de la bibliotecología y las ciencias de la información,» Revista Investigación Bibliotecológica, vol. 29, nº 65, pp. 195-211, 2015. [3]M. A. Montiel Galindo, D. G. Charles Estrada y S. L. Olivares Olivares, «Método de casos como estrategia didáctica para desarrollar el pensamiento crítico en estudiantes de turismo,» Revista Ciencia, Docencia y Tecnología , vol. 29, nº 57, pp. 88-110, 2018. [4]M. Vernier, L. Cárcamo y E. Scheihing, «Pensamiento crítico de los jóvenes ciudadanos frente a las noticias en Chile,» Revista Comunicar, vol. XXVI, nº 54, pp. 101-110, 2018. [5]E. J. Steffens, D. d. C. Ojeda , J. . L. Martínez , H. G. Hernández y Y. H. Moronta, «Presencia del pensamiento crítico en estudiantes de educación superior de la Costa Caribe Colombiana,» Revista Espacios, vol. 39, nº 30, pp. 1-14, 2018. [6]Y. E. Loaiza Zuluaga y L. D. Osorio, «El desarrollo de pensamiento crítico en ciencias naturales con estudiantes de básica secundaria en una Institución Educativa de Pereira – Risaralda,» Revista Diálogos sobre Educación, vol. 9, nº 16, pp. 1-24, 2018. [7]P. Morales Bueno, «Aprendizaje basado en problemas (ABP) y habilidades de pensamiento crítico ¿una relación vinculante?,» Revista Electrónica Interuniversitaria de Formación del Profesorado, vol. 21, nº 2, pp. 91-108, 2018. [8]J. L. Valencia Castro, S. Tapia Vallejo y S. L. Olivares Olivares, «La simulación clínica como estrategia para el desarrollo del pensamiento crítico en estudiantes de medicina,» Revista Investigación en Educación Médica, vol. 8, nº 29, pp. 13-22, 2019. [9]M. E. Godoy Zúñiga y K. M. Calero Cedeño, «Pensamiento crítico y tecnología en la educación universitaria. Una aproximación teórica,» Revista Espacios, vol. 39, nº 25, pp. 1-6, 2018. [10]E. García Carpintero Blas, J. Siles González, E. Martínez Roche, E. Martínez de Miguel y C. Manso Perea, «Percepciones de los estudiantes sobre el desarrollo del pensamiento crítico-reflexivo a través del portafolio de prácticas,» Revista Investigación en Enfermería: Imagen y Desarrollo, vol. 20, nº 1, pp. 1-12, 2018.

Background Positional manoeuvres are an important part of the neurological examination, particularly in patients with vertigo where the presence and characteristics of provoked nystagmus can help differentiate central from peripheral neurological disorders. Methods Case series of functional positional eye and eyelid movements. Results We report four patients with functional eye and eyelid movements provoked during positional manoeuvres. The range of abnormalities observed included positional convergence spasm, brief functional saccadic oscillations, and excessive positional blinking mimicking upbeat nystagmus. The functional movements described were present on a background of pre-existing peripheral or central nystagmus, or positional vertigo. Conclusion Functional positional eye and eyelid movements may co-exist with organic nystagmus that renders an accurate interpretation of the manoeuvre more challenging. A thorough understanding of the clinical features that differentiate these two categories of eye/eyelid movements makes the analysis easier, thus preventing misdiagnosis and avoiding unnecessary investigations.

espanolLa labor docente en las universidades se caracteriza por las competencias investigativas basicas, complementarias y avanzadas, las cuales consolidan la relacion con el estudiante en su proceso de formacion academica. En la presente investigacion se planteo como objetivo “identificar las competencias investigativas del docente universitario a partir de su autopercepcion”. Para ello se desarrollo el enfoque cuantitativo, de tipo descriptivo, con diseno no experimental, metodo analitico, tecnica de la encuesta e instrumento – cuestionario cerrado, el cual se realizo a 36 profesionales, en su labor como docentes en las universidades de la Region Piura – Peru. Como principal resultado se obtuvo que la participacion activa del docente universitario involucra la difusion o divulgacion de la investigacion en revistas cientificas, concluyendose que si existe autopercepcion de la labor docente en su rol como investigador en la universidad. EnglishThe teaching work in universities is characterized by basic, complementary and advanced research skills, which consolidate the relationship with the student in their academic training process. In the present investigation, the objective was “to identify the research competencies of the university teacher based on their self-perception”, for this purpose the quantitative approach was developed, of a descriptive type, with a non-experimental design, analytical method, survey technique and instrument - closed questionnaire, which was conducted to 36 professionals, in their work as teachers in the universities of the Piura Region - Peru. As a main result, it was obtained that the active participation of the university teacher involves the dissemination or dissemination of research in scientific journals, concluding that there is self-perception of the teaching work in its role as a researcher in the university.

The IUCN has listed the long-whiskered owlet (

Cocoa cultivation is of considerable economic and social importance to the Amazonas region and is commonly associated with forest species in the region. However, the diversification level and composition of cacao agroforestry systems in Peru are poorly understood. The objective of this study is, therefore, to describe the diversity of tree species in cocoa AFS by plantation age. Accordingly, the number of species of 15 plots covering a total of 1.5 hectares was recorded. Moderately low levels of tree species diversity were reported (H´ ranged 0.89–1.45). In total 17 species were reported throughout the study area. The most abundant botanical family was represented by a single Musa sp. species. The dissimilarity indices show a moderate similarity between the age ranges evaluated (over 62%). Additionally, the IVI indicates that the most important species are used for food and timber apart from providing shade, additionally major of this species are introduced intentionally for the farmers. Based on the observations, it may be concluded that the farmer’s interest in obtaining further benefits from the plot, mostly economic benefits affect the diversification of cocoa agroforestry systems.

Icing has become a hot topic both in academia and in the industry given its implications in transport, wind turbines, photovoltaics, and telecommunications. Recently proposed de-icing solutions involving the propagation of acoustic waves (AWs) at suitable substrates may open the path for a sustainable alternative to standard de-icing or anti-icing procedures. Herein, the fundamental interactions are unraveled that contribute to the de-icing and/or hinder the icing on AW-activated substrates. The response toward icing of a reliable model system consisting of a piezoelectric plate activated by extended electrodes is characterized at a laboratory scale and in an icing wind tunnel under realistic conditions. Experiments show that surface modification with anti-icing functionalities provides a synergistic response when activated with AWs. A thoughtful analysis of the resonance frequency dependence on experimental variables such as temperature, ice formation, or wind velocity demonstrates the application of AW devices for real-time monitoring of icing processes., ERDF (FEDER) A way of making Europe PID2019-110430GB-C21 PID2019-109603RA-I00 PID2020-112620GB-I00 MCIN/AEI/10.13039/501100011033, European Commission EU H2020 program 899352

En este capítulo se presenta un CIMA para un curso de física general de pri- mero del grado de matemáticas, en concreto sobre el tema concerniente al movi- miento relativo. Los principios docentes que se han priorizado en este CIMA han sido crear un entorno para el aprendizaje crítico natural, guiar a los estudiantes al razonamiento disciplinar y crear experiencias de aprendizaje diversas. El mo- delo metodológico seguido ha consistido en sesiones cortas de teoría en las que se incluían casos cotidianos relacionados seguidos de sesiones cortas de proble- mas para afianzar los conceptos. Tras cada bloque de contenido se realizaba una sesión de problemas mayor que abarcaba y relacionaba las distintas secciones. Este modelo se complementó con vídeos que mostraban situaciones físicas insó- litas y con un ejemplo complejo sacado de la vida cotidiana. Palabras clave: Física I, grado en matemáticas, docencia universitaria, desa- rrollo profesional.