3,302 research outputs found
Application of the biomization technique in the Eastern Colombian Andes
Two pollen records (Lake Fuquene and Pantano de Martos) are analyzed in order to test the usefulness of the Biomization technique to management on forest adaptation to climate change. This work focuses on Biomes and Plant Functional Types response to climate changes on specific dates (18, 14, 12.5, 8 and 6 Kyr) along the Late Quaternary, as deduced from the pollen composition. Results show different responses of vegetation to changes in past environmental conditions, which can be attributed to the different altitudes of the two study sites. While biomes in Lake Fuquene (2500 m a.s.l.) shift from Cool Grassland at 18 Kyr to Cool Mixed Forest and Cool evergreen Forest at 6 Kyr ago, no biome shift is detected in Pantano de Martos (3200 m a.s.l.) through the Late Quaternary. A look to the different Plant Functional Types taking part on the surroundings of the study sites at different ages, together with the analyses of Arboreal / Non Arboreal pollen percentages, give a detailed idea of the ecosystem response to past climate changes. This study shows the potential of the Biomization technique as a simple and powerful tool to analyze ecosystem responses at local and regional scales
Professional Educational Offer And Its Impact On The Labour Market
The fact that in México a large part of the population has access to higher education institutions, both public and private, does not indicate that the students are going to have the opportunity of developing the knowledge acquired in the university. Unemployment is often present; therefore their hopes to get a better life are diminished. Nowadays, students have a college degree, but they do not have any place to work. What is worse is that they cannot go back to their place of origin, because they are not accustomed to the former life or any other profession that they would have probably exercised if they had not lived in the city, causing underemployment. The higher education system in Puebla shows a high efficiency to cover the requirements of skilled labour of the economy, but it is not its duty to improve the performance of the economic and political institutions in order to reach an efficient and dynamic economy. It is worth mentioning that urgent actions are required to improve social conditions, as part of an integral strategy, which will allow the Mexican economy to increase the competitiveness of the companies, and thus achieve a greater job demand
Species distribution models and climatic niche comparisons provide clues on the geographic origin of a spider invasion in the Americas
Identifying the source population of alien species is important to assess the distribution and potential effects in the invaded area. The araneid spider Cyrtophora citricola is widely distributed in Europe, Asia, and Africa; however, in the last 26 years, it has been reported in several countries across the Americas. To date, the geographic origin of the populations established in the Americas remains unclear, but considering the successful colonization after its recent arrival, assessing climatic similarities between the invaded and native geographic ranges could be useful to address this question. In this study, we used a combination of Species Distribution Models and Ordination Methods to assess the climatic match between the invaded region (the Americas) and two potential origins (southern Africa and the Mediterranean) aiming to determine the more likely origin for the populations established in the Americas. We found that the American populations of C. citricola occupy sites with climatic conditions more similar to those occupied by southern African populations, than to those occupied by the Mediterranean populations. Therefore, our results suggest a southern African rather than a Mediterranean origin for the populations established in America. In addition, our results also show that populations in America are spreading into sites that differ in climate conditions from those occupied by native populations. Further studies assessing intrinsic (e.g., physiological tolerances, plasticity, behavior, reproduction) and extrinsic (physical barriers, predator release) factors could provide further information to disentangle the mechanisms behind the geographic and climatic niche expansion of this species
CHARACTERIZATION OF THE SMALL-SCALE MILK PRODUCTION SYSTEM IN THE SOUTHEASTERN ZONE OF ESTADO DE MÉXICO
El objetivo fue caracterizar el sistema de producción de leche en pequeña escala (SPLPE) de la región Suroriente del Estado de México. Se aplicó una encuesta semiestructurada a la población (153 productores) correspondientes a los municipios de Amecameca y Ayapango; considerando dimensiones productivas (escala), técnicas (sistema productivo) y sociales (fuerza de trabajo). Para caracterizar se utilizó un Análisis Factorial por componentes principales y posteriormente un Análisis Clúster. A partir del análisis factorial se obtuvieron cinco factores que explican el 66 % de la variación total, el primer factor los agrupa por escala, el segundo por nivel educativo, el tercero por diversidad agropecuaria, cuarto por prácticas de manejo sanitario y el último por la capacidad de permanecer a lo largo del tiempo. El Análisis Clúster permitió identificar tres grupos de productores, el primero con mayor escala y con menor producción, el segundo con menor escala pero mayor cantidad de leche por vaca, mientras que el tercero se encuentra entre los anteriores. Se concluye que la producción en pequeña escala es heterogénea, el nivel productivo es bajo, no se emplean tecnologías productivas y el sistema se considera de subsistencia, aunque existe un grupo de con potencial para incrementar la producción de leche
Primary elections and electoral outcomes: evidence from the Spanish Socialist Party
Using a regression discontinuity design and primary elections to select Spanish Socialist Party (PSOE) mayoral candidates as a case study, this paper investigates the causal link between primary elections and electoral outcomes. The results suggest that selecting the PSOE’s mayoral candidate through primary elections has no effect on the percentage of votes and total votes received by the PSOE’s candidate in local elections, the probability of gaining the mayorship and the local government’s stability. On the other hand, the results suggest that PSOE’s primary elections result in increased votes for competing political parties to the right of the PSOE and in reduced votes for competing parties to the left of the PSO
Conservación del elemento boreo-alpino del sistema central: Microrreserva de los circos de Cerezuelo y Buitrera
El entorno del Pico del Lobo es uno de los enclaves del Sistema Central con una mayor diversidad de taxones eurosiberianos y boreo-alpinos, presentando además diversos hábitats de carácter atlántico y orófilo bien conservados. La presencia en la zona de dos especies del Catálogo de Flora Protegida regional,Swertia perennis L. y Huperzia selago (L.) Bernh. ex Schrank & Mart .subsp. selago y en el marco del Decreto 63/2007 de la Junta de Castilla y León, se propone la creación de la presente Microrreserva de Flora
Additional information delivery to image content via improved unseen–visible watermarking
In a practical watermark scenario, watermarks are used to provide auxiliary information; in this way, an analogous digital approach called unseen–visible watermark has been introduced to deliver auxiliary information. In this algorithm, the embedding stage takes advantage of the visible and invisible watermarking to embed an owner logotype or barcodes as watermarks; in the exhibition stage, the equipped functions of the display devices are used to reveal the watermark to the naked eyes, eliminating any watermark exhibition algorithm. In this paper, a watermark complement strategy for unseen–visible watermarking is proposed to improve the embedding stage, reducing the histogram distortion and the visual degradation of the watermarked image. The presented algorithm exhibits the following contributions: first, the algorithm can be applied to any class of images with large smooth regions of low or high intensity; second, a watermark complement strategy is introduced to reduce the visual degradation and histogram distortion of the watermarked image; and third, an embedding error measurement is proposed. Evaluation results show that the proposed strategy has high performance in comparison with other algorithms, providing a high visual quality of the exhibited watermark and preserving its robustness in terms of readability and imperceptibility against geometric and processing attacks
Modulating climacteric intensity in melon through QTL stacking
Fruit ripening is one of the main processes affecting fruit quality and shelf life. In melon there are both climacteric and non-climacteric genotypes, making it a suitable species to study fruit ripening. In the current study, in order to fine tune ripening, we have pyramided three climacteric QTLs in the non-climacteric genotype “Piel de Sapo”: ETHQB3.5, ETHQV6.3 and ETHQV8.1. The results showed that
the three QTLs interact epistatically, affecting ethylene production and ripening-related traits such as aroma profile. Each individual QTL has a specific role in the ethylene production profile. ETHQB3.5 accelerates the ethylene peak, ETHQV6.3 advances the ethylene production and ETHQV8.1 enhances the effect of the other two QTLs. Regarding aroma, the three QTLs independently activated the
production of esters changing the aroma profile of the fruits, with no significant effects in fruit firmness, soluble solid content and fruit size. Understanding the interaction and the effect of different ripening QTLs offers a powerful knowledge for candidate gene identification as well as for melon breeding programs, where fruit ripening is one of the main objectives.info:eu-repo/semantics/publishedVersio
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