Sapientia
Repositório Científico da UAlg
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Exploring the use of data envelopment analysis for formative evaluation of senior high schools in ghana
Publication . Aikins, Emmanuel; Pereira dos Santos, Sérgio; Amado, Carla
This study explores the use of data envelopment analysis (DEA) for the formative evaluation of senior high schools (SHS) in Ghana and investigates how the DEA results can help improve their performance. By assessing the relative performance of 215 public SHS across five regions (Greater Accra Region, Ashanti Region, Central Region, Upper West Region, and Upper East Region), the study contributes to the broader discourse on knowledge-based economies by demonstrating how data-driven insights can optimize resource allocation and improve human capital development. The schools are classified into groups A, B, and C based on students’ entrance examination scores, and a hierarchical categorization DEA procedure is applied to assess them across three dimensions: resource efficiency, resource effectiveness, and effectiveness. This study highlights the crucial role of knowledge creation, diffusion, and application in education management by fostering deep engagement with decision-makers, ensuring the acceptance of DEA results, and promoting continuous improvement in institutional performance. The findings reveal significant disparities in school efficiency and effectiveness, underscoring the need for structured knowledge-sharing mechanisms. To support sustained performance improvement and better resource utilization, we propose the establishment of an educational performance observatory. This initiative would function as a platform for knowledge diffusion, enabling underperforming schools to benchmark against high-performing institutions, thus reinforcing the foundational role of knowledge exchange in strengthening educational systems and, by extension, the knowledge economy.
A demographic model to forecast Dinophysis acuminata harmful algal blooms
Publication . Vieira, Vasco Manuel Nobre de Carvalho da Silva; Leal Rosa, Teresa; Sobrinho-Gonçalves, Luís; Mateus, Marcos Duarte; Mota, Bernardo
Harmful algal blooms (HABs) in marine environments have significant adverse effects on public health, aquaculture and recreational activities. Surges of certain phytoplanktonic toxin-producing microalgae (mostly dinoflagellates or diatoms species) can induce Amnesic, Diarrhetic or Paralytic Shellfish Poisoning (ASP, DSP and PSP). Among HAB species, the genus Dinophysis leads to DSP in human consumers; this being the most recurrent problem in the Iberian Peninsula with the biggest economic impact on clam production and harvesting. While complete elimination of HABs is not feasible, timely implementation of appropriate measures can prevent their negative consequences. This is critical for aquaculture. Research on D. acuminata (dominant Dinophysis species in the North Atlantic) has been focused on ecophysiology and population dynamics, although with few modelling attempts. Weekly monitoring along the Portuguese coast since 2006 has revealed that D. acuminata thrives under spring/summer photosynthetically active radiation (PAR) coupled with water temperatures below 20°C, which typically coincide with the local upwelling regime. In order to advance this knowledge numerically, we developed a demographic model linking D. acuminata growth rate to PAR and sea surface temperature (SST). The 13-year (1-Jan-2006 to 31-Dec-2018) time-series of observations was closely fit by model forecasts. However, the model demonstrated limitations in issuing timely warnings of harmful proliferation of D. acuminata, failing to do so in 50% of cases, and issuing incorrect warnings in 5% of the cases. Furthermore, improving the odds of emitting timely warnings always worsened the odds of emitting false warnings, and vice-versa. To simultaneously improve both aspects, the modelling results clearly indicated the need of implementing both census/ projection intervals smaller than 7 days and a laboratory detection limit below 20 cell/L. The time resolution of the census and of the model proved to be the most limiting factor that must be addressed in order to improve numerical forecasting of HABs.
Les rondalles que l’arxiduc no va publicar
Publication . Correia, Paulo
É sobejamente conhecido, sobretudo entre os folcloristas (mas que também é sentido pela gente comum) que a milenar literatura de tradição oral entrou em decadência por ter perdido a sua função de entreter e educar os povos nas sociedades industriais ou pós-industriais. As primeiras recolhas de literatura oral aconteceram no século xix por ação do ideário do Romantismo, onde se considerava que quem representava o “espírito” das várias nações era o “povo” e suas tradições, sobretudo as de transmissão oral. Os dois primeiros países a interessar-se por essa tradição armazenada na memória de indivíduos pertencentes a uma população maioritariamente rural, foram a Alemanha e a Grã-Bretanha. Simultaneamente, foram também estes países que começaram mais cedo a sua Revolução Industrial, com consequências trágicas para as sociedades campesinas. Com plena consciência da rápida desintegração das condições que permitiram a este conhecimento memorial ser transmitido oralmente através das gerações, e verificando no terreno que a cada década que passasse era cada vez mais difícil encontrar testemunhos válidos do mesmo, lançaram o alarme: é preciso salvar o que ainda é possível salvar, antes do seu desaparecimento total, registrando essas tradições através da escrita em suportes duradouros, como os livros.
Rhodolith beds in the Eastern Tropical Pacific: Habitat structure and associated biodiversity
Publication . Diaz-Licona, Celeste A.; Schubert, Nadine; González-Gamboa, Vladimir; Tuya, Fernando; Azofeifa-Solano, Juan Carlos; Fernández-García, Cindy
Rhodolith beds (RBs) are globally distributed marine benthic habitats and recognized biodiversity hotspots of conservation interest. However, considerable regions of the world’s oceans remain unknown in terms of the presence, distribution, structure, and associated biodiversity of such habitats. In the Eastern Tropical Pacific (ETP), even basic information about these habitats is still extremely scarce. To fill this gap, we characterized the habitat structure and associated biodiversity of four shallow-water RBs at Cocos Island, Costa Rica. Specifically, information regarding rhodolith structural attributes (size, morphology, and CaCO3 content), as well as habitat characteristics (rhodolith nodule density, biomass and CaCO3 standing stocks) were collected. Moreover, the diversity and abundance of associated organisms, including macroalgae, invertebrates and fishes, were determined. Our study shows that Cocos Island harbors dense RBs (1,100 to >4500 nodules m-2) with substantial carbonate stocks (14-22 kg m-2), which provide habitats for a wide array of species (158 recorded species). This study adds 58 new records of RB-associated species to previously published records for the island, which increases the total number of species to 316, including 51 species endemic to the ETP and four species categorized as vulnerable by the IUCN. Our results also indicate that community composition and abundance of organisms vary among RBs, likely due to differences in rhodolith morphologies and sizes and/or local environmental conditions. Further research efforts are warranted to identify the drivers for these differences, as well as expanding studies towards other RBs at Cocos Island and in the ETP in general.
Análise Bioinformática da Via Hedgehog em Cancros Humanos: Expressão, Metilação e Impacto Prognóstico no KIRC e LGG
Publication . Aguiar, Diogo Gonçalo Ribeiro Paulo e Soares; Tavares, Álvaro
O cancro é um dos maiores desafios da saúde global, resultando de alterações genéticas, epigenéticas e da desregulação de vias de sinalização. Esta tese centrou-se na via Hedgehog (HH), conservada evolutivamente e crucial no desenvolvimento embrionário, frequentemente desregulada em vários tipos de neoplasias. O objetivo principal foi analisar a expressão diferencial dos genes da via HH e associados em diversos cancros, com foco no carcinoma renal de células claras (KIRC) e no glioma de baixo grau (LGG), avaliando também o seu impacto prognóstico e potenciais mecanismos regulatórios.
Utilizando abordagens bioinformáticas e bases de dados públicas (TCGA, GTEx, GEPIA2, cBioPortal, MethSurv, STRING, TIMER2.0, UCSC Xena Browser e UALCAN), foram analisados dados de expressão génica, metilação de DNA, mutações, infiltração imune e interações moleculares. Verificaram-se diferenças relevantes na expressão de CDON e LRP2 (KIRC) e de KIF7, BOC, CSNK1A1, CSNK1G3, PTCH1, GAS1, SMO e SUFU (LGG) entre tecidos tumorais e normais. A expressão elevada de LRP2 e CDON associou-se a melhor sobrevivência em KIRC, enquanto SUFU e PTCH1 mostraram efeito protetor em LGG. Por outro lado, SMO e GAS1 foram associados a pior prognóstico em LGG.
Foi ainda observada hipermetilação dos promotores de CDON e LRP2 em KIRC, sugerindo regulação epigenética, enquanto em LGG a desregulação parece ocorrer por mecanismos não mutacionais. As redes de coexpressão revelaram interações com vias como Wnt e PI3K/AKT.
Conclui-se que a via HH tem impacto distinto consoante o subtipo tumoral, e alguns genes, como LRP2 e CSNK1A1, podem constituir biomarcadores ou alvos terapêuticos promissores, reforçando a importância de análises multi-ómicas aplicadas à oncologia de precisão.