ALBERT

Description: Intensification of agriculture worldwide has led to a growing awareness on their environmental impacts, namely on soil quality and long term impact on crop productivity. As a consequence, there is an increasing concern regarding best agricultural management practices and their impact on physical, chemical and biological soil properties. In the Centre region of Portugal, maize is one of the most important arable crops and represents more than 32% of the cultivated area. Maize fields have been intensively managed under conventional practices, but increasing land degradation is leading farmers to adopt improved management practices, such as the application of composted sludge from urban wastewater treatment plants. This study aims to assess the long term impact of composted sludge application as soil amendment in maize cropping fields. The study was performed in Baixo Mondego, in central region of Portugal, largely devoted to agriculture and where maize is one of the most relevant crops. The study was performed in two study sites with similar soil and weather characteristics - one managed under conventional practices, with intensive application of fertilizers, and another field where a significant part of mineral fertilizers is replaced by composted sludge. Both sites use these agricultural management practices for more than 5 years. In 2018, two soil sampling campaigns were performed to assess the physical (texture and bulk density) and chemical soil properties (organic matter content, total nitrogen, total and extractable phosphorus, exchangeable cation (K+, Ca2+, Na+, Mg2+) and heavy metals (Cd, Cr, Pb, Zn and Ni)). Results show that composted sludge improves soil organic matter content (1.2% vs. 2.2%), total (2747 mg kg-1 vs. 1134 mg kg-1) and available phosphorous (821.85 mg kg-1 vs. 98.44 mg kg-1) comparing with conventional management practices. Higher contents of heavy metals, specifically Cu, Zn, Cd and Cr, were found in the field with sludge application than in the conventional one, which may represent a long term risk for soil contamination. Information regarding the long term impacts of best management practices on soil quality is relevant and should guide farmers and policy makers to attain agricultural sustainability.

Description: The Millennium Ecosystem Assessment (MA) initiated in 2001 aims to assess the impacts of human pressure on ecosystem services (ES) and human well-being. Since then, the ES have been a worldwide concern, namely regarding to biodiversity loss and land use management (MA, 2005). The EU 2010 Biodiversity Baseline Report stated that 65% of habitats of EU importance were in an unfavorable conservation status, mainly due to anthropic activities over time (EEA, 2010). As a consequence, in 2011, the EU adopted the Biodiversity Strategy to 2020, requiring all Member States to actively work towards stopping the loss of biodiversity and ecosystem services by 2020, and to restore ecosystems. ES are particularly relevant in urban areas, where most population is concentrated and expected to reach almost 70% of the total population by 2050 (UN-DESA, 2018). Strategically planned urban Green and Blue Infrastructures (GBI) can be designed and implemented in cities to effectively provide a wide range of ES, relevant to address urban sustainability and resilience to climate change, and thus effectively contribute to stop and revert ES deterioration and loss. However, the integration of ES and GBI concepts into national, regional and local policies and plans, and their effectiveness to implement the EU Biodiversity Strategy, is still a major challenge. This paper aims to analyze the horizontal and vertical integration of the ES and GBI concepts in the Portuguese policies and land use planning, at national, regional and local levels, focusing on the municipality of Coimbra. Among the 19 documents analyzed, most of them are defined at national level (12) and 6 of them are defined at local level. At the regional level, only one single plan is available, although it is still not officially approved and published, despite started being prepared in 1991. This regional situation mirrors the current status of the Portuguese administrative levels, which was triggered by the negative result of the 1998 referendum on the regionalization process. This referendum prevented necessary changes in the administrative divisions, so that current regional divisions do not reflect the economic, demographic and cultural realities of the country, having been emptied of administrative powers. The analysis shows a strong integration of the ES and GBI concepts at the national level, but the vertical coordination shows that plenty of work needs to be done to fully embrace the ES and GBI concepts. This research was performed in the UrbanGaia project, funded through the ERA-net BiodivERsA 3 2015 call under grants BRAIN-be BR/175/A1/URBANGAIA-BE (Belgium); 01LC1616A (Germany); S-BIODIVERSA-17-17-1 (Lithuania), and BIODIVERSA/0008/2015 (Portugal).

Description: Chitin was extracted from Polybius henslowii, a swimming crab, captured in large quantities throughout the Portuguese coast by purse seine vessels as bycatch. After standard chitin extraction procedures, water-soluble chitosan products were obtained via two different methods: (1) N-acetylation with the addition of acetic anhydride and (2) a reaction with hydrogen peroxide. The chemical structure and molecular weight of chitosan derivatives, water-soluble chitosan (WSC) and chitooligosaccharides (COS), were confirmed by Fourier Transform Infrared Spectroscopy (FT-IR) and gel permeation chromatography (GPC). Antioxidant and metal chelation activities were evaluated, and the growth inhibition capacity was tested on four phytopatogens. The chitooligosaccharides from pereopods (pCOS) and shell body parts (sCOS) inhibited all fungal species tested, particularly Cryphonectria parasitica with 84.7% and 85.5%, respectively. Both radical scavenging and antifungal activities proved to be dose-dependent. Chitooligosaccharides with a low molecular weight (2.7, 7.4, and 10.4 Kg·mol−1) showed the highest activity among all properties tested. These results suggested that chitosan derivatives from P. henslowii raw material could potentially be used against phytopathogens or as ingredient in cosmetics and other products related to oxidative stress.

Description: This paper studies the evolution of overconfidence over a cohort’s working life. To do this, the paper incorporates subjective assessments into a continuous time human capital accumulation model with a finite horizon. The main finding is that the processes of human capital accumulation, skill depreciation, and subjective assessments imply that overconfidence first increases and then decreases over the cohort’s working life. In the absence of skill depreciation, overconfidence monotonically increases over the cohort’s working life. The model generates four additional testable predictions. First, everything else equal, overconfidence peaks earlier in activities where skill depreciation is higher. Second, overconfidence is lower in activities where the distribution of income is more dispersed. Third, for a minority of individuals, overconfidence decreases over their working life. Fourth, overconfidence is lower with a higher market discount rate. The paper provides two applications of the model. It shows the model can help make sense of field data on overconfidence, experience, and trading activity in financial markets. The model can also explain experimental data on the evolution of overconfidence among poker and chess players.

Description: In the last years, the extracellular matrix (ECM) has been reported as playing a relevant role in esophageal cancer (EC) development, with this compartment being related to several aspects of EC genesis and progression. This sounds very interesting due to the complexity of this highly incident and lethal tumor, which takes the sixth position in mortality among all tumor types worldwide. The well-established increase in ECM stiffness, which is able to trigger mechanotransduction signaling, is capable of regulating several malignant behaviors by converting alteration in ECM mechanics into cytoplasmatic biochemical signals. In this sense, it has been shown that some molecules play a key role in these events, particularly the different collagen isoforms, as well as enzymes related to its turnover, such as lysyl oxidase (LOX) and matrix metalloproteinases (MMPs). In fact, MMPs are not only involved in ECM stiffness, but also in other events related to ECM homeostasis, which includes ECM remodeling. Therefore, the crucial role of distinct MMPs isoform has already been reported, especially MMP-2, -3, -7, and -9, along EC development, thus strongly associating these proteins with the control of important cellular events during tumor progression, particularly in the process of invasion during metastasis establishment. In addition, by distinct mechanisms, a vast diversity of glycoproteins and proteoglycans, such as laminin, fibronectin, tenascin C, galectin, dermatan sulfate, and hyaluronic acid exert remarkable effects in esophageal malignant cells due to the activation of oncogenic signaling pathways mainly involved in cytoskeleton alterations during adhesion and migration processes. Finally, the wide spectrum of interactions potentially mediated by ECM may represent a singular intervention scenario in esophageal carcinogenesis natural history and, due to the scarce knowledge on the cellular and molecular mechanisms involved in EC development, the growing body of evidence on ECM’s role along esophageal carcinogenesis might provide a solid base to improve its management in the future.

Description: Hypoxia is an inherent condition of tumors and contributes to cancer development and progression. Hypoxia-inducible factors (HIFs) are the major transcription factors involved in response to low O2 levels, orchestrating the expression of hundreds of genes involved in cancer hallmarks’ acquisition and modulation of epigenetic mechanisms. Epigenetics refers to inheritable mechanisms responsible for regulating gene expression, including genes involved in the hypoxia response, without altering the sequence of DNA bases. The main epigenetic mechanisms are DNA methylation, non-coding RNAs, and histone modifications. These mechanisms are highly influenced by cell microenvironment, such as O2 levels. The balance and interaction between these pathways is essential for homeostasis and is directly linked to cellular metabolism. Some of the major players in the regulation of HIFs, such as prolyl hydroxylases, DNA methylation regulators, and histone modifiers require oxygen as a substrate, or have metabolic intermediates as cofactors, whose levels are altered during hypoxia. Furthermore, during pathological hypoxia, HIFs’ targets as well as alterations in epigenetic patterns impact several pathways linked to tumorigenesis, such as proliferation and apoptosis, among other hallmarks. Therefore, this review aims to elucidate the intricate relationship between hypoxia and epigenetic mechanisms, and its crucial impact on the acquisition of cancer hallmarks.

Description: Unmanned Aerial Vehicles (UAVs) can be a powerful tool for live (interactive) remote inspection of large-scale structures or areas of interest. Instead of manual, local, and labor-intensive inspections, we envision human operators working together with networks of semi-autonomous UAVs. The current state-of-the-art for low-delay high-throughput inter-vehicle networking relies on Time-Division Multiple Access (TDMA) techniques that require accurate synchronization among all network nodes. In this paper, we propose a delay-tolerant synchronization approach that converges to the correct order of the TDMA slots implemented over COTS WiFi in a fully-distributed way and without resorting to a global clock. This highly flexible solution allows building an ad-hoc aerial network based on a backbone of relaying UAVs. We show several alternatives to achieve this synchronization in a concrete aerial network and compare them in terms of slots’ overlap, throughput, and packet delivery. The results show that these alternatives lead to trade-offs in the referenced metrics. The results also provide insight into the delays caused by buffering in the protocol stack and especially in the WiFi interface.

Description: Endometrioid endometrial carcinomas (EEC) are the most common malignant gynecologic tumors. Despite the increase in EEC molecular knowledge, the identification of new biomarkers involved in disease’s development and/or progression would represent an improvement in its course. High-mobility group A protein (HMGA) family members are frequently overexpressed in a wide range of malignancies, correlating with a poor prognosis. Thus, the aim of this study was to analyze HMGA1 and HMGA2 expression pattern and their potential role as EEC biomarkers. HMGA1 and HMGA2 expression was initially evaluated in a series of 46 EEC tumors (stages IA to IV), and the findings were then validated in The Cancer Genome Atlas (TCGA) EEC cohort, comprising 381 EEC tumors (stages IA to IV). Our results reveal that HMGA1 and HMGA2 mRNA and protein are overexpressed in ECC, but only HMGA1 expression is associated with increased histological grade and tumor size. Moreover, HMGA1 but not HMGA2 overexpression was identified as a negative prognostic factor to EEC patients. Finally, a positive correlation between expression of HMGA1 pseudogenes—HMGA1-P6 and HMGA1-P7—and HMGA1 itself was detected, suggesting HMGA1 pseudogenes may play a role in HMGA1 expression regulation in EEC. Thus, these results indicate that HMGA1 overexpression possesses a potential role as a prognostic biomarker for EEC.