Assessing the effects of the Prestige oil spill on the European shag (Phalacrocorax aristotelis): trace elements and stable isotopes

The Prestige oil spill resulted in the mortality of several seabird species on the Atlantic NW coast of Spain. Shag casualties were particularly relevant, since populations are resident in the area the whole year round and because of several features which make them highly vulnerable to environmental hazards. Ecological catastrophes give us the opportunity of collecting samples which, otherwise, would be difficult to obtain. We examine the potential of shag corpses as bioindicators of inorganic pollution and the possible factors of variability, such as biological traits (sex, age) or nutrition status. We determined trace elements (Hg, Se, Cr, Pb, Zn and Cu) and isotopic signatures (¹⁵N, ¹³C) in soft tissues (muscle, liver) and in primary feathers formed at different times (before and after the Prestige) in individuals of known sex and age, collected at the time of the Prestige disaster. These were compared with data from another group of shags trapped accidentally in fishing gear in 2005.Our results did not seem to be affected by sex or age on any of the analysed variables. The higher nitrogen isotopic signatures in the soft tissues of the Prestige shags may be related to the nutrition stress caused by a poorer body condition, which is also reflected in increasing levels of some metals in the liver. This isotopic enrichment was also observed in newly forming feathers when compared to the old ones. On the other hand, the lower δ¹⁵N and Hg values in shag feathers from 2005 point to a shift in feeding resources to prey of lower trophic levels. We found that feather features (being an inert tissue and having a conservative composition), if combined with careful dating and chemical analysis, offer a very useful tool to evaluate temporal and spatial changes in seabird ecology in relation to pollution events.     

Polymer-clay nanocomposites as precursors of nanostructured carbon materials for electrochemical devices: templating effect of clays

The present work introduces a comparative study on the use of polymer nanocomposites containing clay minerals of different structure, such as montmorillonite and sepiolite as host solids for the templating synthesis of carbon-like materials from different organic precursors. Carbon-clay nanocomposites were obtained by polymerization of either acrylonitrile or sucrose previously inserted in the pores of the clay minerals, followed by their further thermal transformation in carbon-like compounds. Acid treatment of the resulting carbon-clay nanocomposites removes the inorganic templates giving carbon-like materials with different textural features. Polymer-clay, carbon-clay and carbon-like materials have been characterized by applying spectroscopic techniques as FTIR and in situ EIS (electrochemical impedance spectroscopy) and other structural, textural and analytical tools (chemical analysis, XRD, SEM-EDX, TEM-EDX, N2 adsorption isotherms,...). Electrochemical properties of these carbon-clay nanocomposites, as well as their templated carbonaceous materials and their use as electrode materials of different electrochemical devices such as rechargeable Li-batteries, supercapacitors and electrochemical sensors, are also discussed.     

Hyperuricemia is Associated with Increased Apo AI Fractional Catabolic Rates and Dysfunctional HDL in New Zealand Rabbits

The potential cause–effect relationship between uric acid plasma concentrations and HDL functionality remains elusive. Therefore, this study aimed to explore the effect of oxonic acid (OA)-induced hyperuricemia on the HDL size distribution, lipid content of HDL subclasses, and apo AI turnover, as well as HDL functionality in New Zealand white rabbits. Experimental animals received OA 750 mg/kg/day by oral gavage during 21 days. The HDL-apo AI fractional catabolic rate (FCR) was determined by exogenous labeling with ¹²⁵I, and HDL subclasses were determined by sequential ultracentrifugation and PAGE. Paraoxonase-1 activity (PON-1) and the effect of HDL on relaxation of aorta rings in vitro were determined as an indication of HDL functionality. Oxonic acid induced a sixfold increase of uricemia (0.84 ± 0.06 vs. 5.24 ± 0.12 mg/dL, P < 0.001), and significant decreases of triglycerides and phospholipids of HDL subclasses, whereas HDL size distribution and HDL-cholesterol remained unchanged. In addition, HDL-apo AI FCR was significantly higher in hyperuricemic rabbits than in the control group (0.03697 ± 0.0038 vs. 0.02605 ± 0.0017 h^?1 respectively, P < 0.05). Such structural and metabolic changes were associated with lower levels of PON-1 activities and deleterious effects of HDL particles on endothelium-mediated vasodilation. In conclusion, hyperuricemia is associated with structural and metabolic modifications of HDL that result in impaired functionality of these lipoproteins. Our data strongly suggest that uric acid per se exerts deleterious effects on HDL that contribute to increase the risk of atherosclerosis.     

A 0.6 V and 0.395 pJ/bit nonius TDC for a passive RFID pressure sensor tag

This work presents a nonius time to digital converter (TDC) adapted to a passive RF identification (RFID) pressure sensor tag. The proposed converter exploits the characteristics of time-based sensor interfaces and allows reducing voltage supply and power consumption while maintaining resolution and conversion efficiency. The nonius TDC has been designed and fabricated using the TSMC 90 nm standard CMOS technology. The main blocks of the converter are described and both the resolution adjustment and measurement processes are explained in detail. Measurement results show 10.49 bits of effective resolution for an input time range from 28.19 to 42.93 μs. With a sampling rate of 19 KS/s the converter has a conversion efficiency of 0.395 pJ/bit with a voltage supply of only 0.6 V. This characteristics in the proposed nonius TDC enables an increased reading range of the passive RFID pressure sensor tag.     

Evaluation of accessibility barriers and learning features in m-learning chat applications for users with disabilities

Universal Access in the Information Society - Chat applications are being used for more than one decade in learning environments as a useful computer-supported collaborative learning tool. However,...     

Personal factors influencing the visual reaction time of pedestrians to detect turn indicators in the presence of Daytime Running Lamps

Daytime running lamps (DRL) on vehicles have proven to be an effective measure to prevent accidents during the daytime, particularly when pedestrians and cyclists are involved. However, there are negative interactions of DRL with other functions in automotive lighting, such as delays in pedestrians’ visual reaction time (VRT) when turn indicators are activated in the presence of DRL. These negative interactions need to be reduced. This work analyses the influence of variables inherent to pedestrians, such as height, gender and visual defects, on the VRT using a classification and regression tree as an exploratory analysis and a generalized linear model to validate the results. Some pedestrian characteristics, such as gender, alone or combined with the DRL colour, and visual defects, were found to have a statistically significant influence on VRT and, hence, on traffic safety. These results and conclusions concerning the interaction between pedestrians and vehicles are presented and discussed.

Practitioner Summary: Visual interactions of vehicle daytime running lamps (DRL) with other functions in automotive lighting, such as turn indicators, have an important impact on a vehicle’s conspicuity for pedestrians. Depending on several factors inherent to pedestrians, the visual reaction time (VRT) can be remarkably delayed, which has implications in traffic safety.     

Saponin Profile of Wild Asparagus Species

The aim of this work was to study the saponin profiles from spears of different wild asparagus species in the context of its genetic diversity aside from geographical seed origin. They included Asparagus pseudoscaber Grecescu, Asparagus maritimus (L.) Mill., Asparagus brachiphyllus Turcz., Asparagus prostrates Dumort., and Asparagus officinalis L. The saponin analysis by LC‐MS has shown that saponin profile from wild asparagus is similar to that previously described for triguero asparagus from Huétor‐Tájar landrace (triguero HT), which had not ever been reported in the edible part of asparagus. All the samples, except A. officinalis, were characterized for having saponins distinct to protodioscin and the total saponin contents were 10‐fold higher than those described for commercial hybrids of green asparagus. In particular, A. maritimus from different origins were rich in saponins previously found in triguero HT. These findings supported previous suggestion, based on genetic analysis, about A. maritimus being the origin of triguero HT. Multivariate statistics including principal component analysis and hierarchical clustering analysis were used to define both similarities and differences among samples. The results showed that the greatest variance of the tested wild asparagus could be attributed to differences in the concentration of particular saponins and this knowledge could be a tool for identifying similar species.     

Combined Treatments with Photodynamic Therapy for Non-Melanoma Skin Cancer

Non-melanoma skin cancer (NMSC) is the most common form of cancer in the Caucasian population. Among NMSC types, basal cell carcinoma (BCC) has the highest incidence and squamous cell carcinoma (SCC) is less common although it can metastasize, accounting for the majority of NMSC-related deaths. Treatment options for NMSC include both surgical and non-surgical modalities. Even though surgical approaches are most commonly used to treat these lesions, Photodynamic Therapy (PDT) has the advantage of being a non-invasive option, and capable of field treatment, providing optimum cosmetic outcomes. Numerous clinical research studies have shown the efficacy of PDT for treating pre-malignant and malignant NMSC. However, resistant or recurrent tumors appear and sometimes become more aggressive. In this sense, the enhancement of PDT effectiveness by combining it with other therapeutic modalities has become an interesting field in NMSC research. Depending on the characteristics and the type of tumor, PDT can be applied in combination with immunomodulatory (Imiquimod) and chemotherapeutic (5-fluorouracil, methotrexate, diclofenac, or ingenol mebutate) agents, inhibitors of some molecules implicated in the carcinogenic process (COX2 or MAPK), surgical techniques, or even radiotherapy. These new strategies open the way to a wider improvement of the prevention and eradication of skin cancer.     

Original article: Anthocyanin profile in Monastrell grapes in six different areas from Denomination of Origen Jumilla during ripening stage

The aim of our research has been to investigate the pattern of accumulation of anthocyanins in the skin of Monastrell variety and to establish if the fingerprint of this cultivar changed in six different areas from Denomination of Origen Jumilla during ripening stage in two consecutive seasons (2007 and 2008). The results show that the anthocyanin profile for Monastrell variety is maintained: it could be observed a higher proportion of non‐acylated anthocyanins, a higher proportion of coumarylated than acetyl derivatives and a higher proportion of trihydroxylated than dihydroxylated anthocyanins. During ripening period, in all zones studied, we observed the same trends: increasing of cyanidin, peonidin and malvidin‐3‐glucoside and decreasing of the other two monoglucosides (delphinidin and petunidin). Slightly quantitative differences were observed for the different zones in the 2 years studied, leading to the conclusion that edaphoclimatic factors also influence the accumulation of anthocyanin compounds.     

Plant Glandular Trichomes as Targets for Breeding or Engineering of Resistance to Herbivores

Glandular trichomes are specialized hairs found on the surface of about 30% of all vascular plants and are responsible for a significant portion of a plant’s secondary chemistry. Glandular trichomes are an important source of essential oils, i.e., natural fragrances or products that can be used by the pharmaceutical industry, although many of these substances have evolved to provide the plant with protection against herbivores and pathogens. The storage compartment of glandular trichomes usually is located on the tip of the hair and is part of the glandular cell, or cells, which are metabolically active. Trichomes and their exudates can be harvested relatively easily, and this has permitted a detailed study of their metabolites, as well as the genes and proteins responsible for them. This knowledge now assists classical breeding programs, as well as targeted genetic engineering, aimed to optimize trichome density and physiology to facilitate customization of essential oil production or to tune biocide activity to enhance crop protection. We will provide an overview of the metabolic diversity found within plant glandular trichomes, with the emphasis on those of the Solanaceae, and of the tools available to manipulate their activities for enhancing the plant’s resistance to pests.