► Tolerance of benthic foraminifera to pollution. ► Metals and mobile phases potentially more or less toxic. ► Mechanisms of defense used by foraminifera in polluted environments. ► A data basis to ...plan lagoonal monitoring studies.
This work analyses the distribution of heavy metals in the sediments of Ria de Aveiro (Portugal) assessed by total digestion and sequential chemical extraction of the sediments. The influence of environmental parameters on the living benthic foraminiferal assemblages was studied. The most polluted parts in the Ria de Aveiro are areas where the residence time is high and cohesive sediments are deposited. Organic matter, which is an excellent scavenger for a number of metals, is in general more abundant in the finer deposits of this lagoon, which act as sinks of anthropogenic pollutants. This condition is observed in Aveiro canals and Murtosa channel where sediments with the highest concentrations of Zn, Pb, Cu, and Cr are found. The sediments of Murtosa channel are also enriched in As, Co and Hg. In Aveiro canals the enrichment of heavy metals is mostly related to the past industrial production at their margins (ceramic and metallurgy), whereas in Murtosa channel with effluent discharges of the Chemical Complex of Estarreja. Foraminiferal density and diversity reach higher values near the lagoon mouth under higher marine influence and decline in general under very low-oxygen conditions. Some species seems to be indifferent to the increasing of TOC (e.g. Haynesina germanica and Ammonia tepida) and some have an opportunistic behaviour in areas with very depressed levels of oxygen (e.g. A. tepida and Quinqueloculina seminulum) whereas other species can better tolerate sulphide/reducing conditions (e.g. H. germanica, Bolivina ordinaria, Buliminella elegantissima, Bulimina elongata/gibba and Nonionella stella) a widespread condition in this lagoon. Foraminiferal density and some species are negatively correlated with concentrations of heavy metals. A most sensitive group of species to higher concentrations of heavy metals is identified (such as B. ordinaria, B. pseudoplicata and B. elongata/gibba) and another one of more tolerant species (such as H. germanica A. tepida and Q. seminulum). Foraminifera are more tolerate higher available concentrations (AC) of Zn in any phase than higher AC of Cu adsorbed do clay minerals (F1) and associated with Fe and Mn oxides (F2) and of Pb in F2; the phase F2, probably the most mobile phase, and even phase F1 seems to be more toxic than the increasing of metals in organic matter (F3).
The discharge of sewage and industrial effluents containing high concentrations of pollutants in water bodies increases eutrophication. Cyanobacteria, some of the organisms whose growth is promoted ...by high nutrient concentrations, are resistant and produce several types of toxins, known as cyanotoxins, highly harmful to human beings. Current water treatment systems for the public water supply are not efficient in degradation of toxins. Advanced oxidation processes (AOP) have been tested for the removal of cyanotoxins, and the results have been positive. This study examines the application of photoelectrooxidation in the degradation of cyanotoxins (microcystins). The performance of the oxidative processes involved was evaluated separately: Photocatalysis, Electrolysis and Photoelectrooxidation. Results showed that the electrical current and UV radiation were directly associated with toxin degradation. The PEO system is efficient in removing cyanotoxins, and the reduction rate reached 99%. The final concentration of toxin was less than 1 µg/L of microcystin in the treated solution.
Misfolded protein oligomers are of central importance in both the diagnosis and treatment of Alzheimer's and Parkinson's diseases. However, accurate high-throughput methods to detect and quantify ...oligomer populations are still needed. We present here a single-molecule approach for the detection and quantification of oligomeric species. The approach is based on the use of solid-state nanopores and multiplexed DNA barcoding to identify and characterize oligomers from multiple samples. We study α-synuclein oligomers in the presence of several small-molecule inhibitors of α-synuclein aggregation as an illustration of the potential applicability of this method to the development of diagnostic and therapeutic methods for Parkinson's disease.
The joint process between tapes of coated conductors is a critical issue for most applications of high temperature superconductors (HTSs). In this work several lap joints using different techniques ...were prepared for three different types of commercially available YBCO-coated conductor tapes, with and without copper stabilizer or stainless steel reinforcement layers. Lap joints with effective lengths in the range of 3 to 20 cm were prepared using low melting point In–Sn and Sn–Pb alloys as soldering materials. The electrical resistance, the critical current, and the
n
-index of the joints were calculated from the electric field
vs
. current (
E
×
I
) characteristic curves under DC current tests and by further subjecting the same samples to tensile stresses. The results showed that the reinforced tape is the more robust tape for the joint-making process, whereas the copper-stabilized tape presented the lowest joint resistivity but with a relatively smaller mechanical strength against tensile stress.
The biological role of carbon monoxide (CO) has completely changed in the last decade. Beyond its widely feared toxicity, CO has revealed a very important biological activity as a signaling molecule ...with marked protective actions namely against inflammation, apoptosis and endothelial oxidative damage. Its direct use as a therapeutic gas showed significant and consistent positive results but also intrinsic severe limitations. The possibility of replacing the gas by pro-drugs acting as CO-Releasing Molecules (CO-RMs) has clearly been demonstrated with several experimental compounds. Transition metal carbonyls complexes have proven to be the most versatile experimental CO-RMs so far. Presently, the challenge is to equip them with drug-like properties to turn them into useful pharmaceuticals. This requires studying their interactions with biological molecules namely those that control their pharmacokinetic and ADME profiles like the plasma proteins. In this account we analyze these questions and review the existing interactions between Metal Carbonyls and proteins. The recently explored case of CORM-3 is revisited to exemplify the methodologies involved and the importance of the results for the understanding of the mode of action of such pro-drugs.
Aims
The aim of this study was to evaluate the chemical and microbiological characteristics and to identify the lactic acid bacteria (LAB) and yeasts involved in rehydrated corn kernel silage.
...Methods and Results
Four replicates for each fermentation time: 5, 15, 30, 60, 90, 150, 210 and 280 days were prepared. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and PCR‐based identification were utilized to identify LAB and yeasts. Eighteen bacteria and four yeast species were identified. The bacteria population reached maximum growth after 15 days and moulds were detected up to this time. The highest dry matter (DM) loss was 7·6% after 280 days. The low concentration of water‐soluble carbohydrates (20 g kg−1 of DM) was not limiting for fermentation, although the reduction in pH and acid production occurred slowly. Storage of the rehydrated corn kernel silage increased digestibility up to day 280.
Conclusions
This silage was dominated by LAB but showed a slow decrease in pH values. This technique of corn storage on farms increased the DM digestibility.
Significance and Impact of the Study
This study was the first to evaluate the rehydrated corn kernel silage fermentation dynamics and our findings are relevant to optimization of this silage fermentation.
Aim
To explore the care experiences of Aboriginal and Torres Strait Islander Australians diagnosed with cirrhosis with a focus on support needed.
Background
Cirrhosis disproportionately affects ...Indigenous Australians, and liver diseases contribute to the mortality gap between Indigenous and other Australian adults.
Design
A qualitative study.
Methods
Using yarning methods, Indigenous patients (n = 13) and support persons (n = 3) were interviewed by an Aboriginal researcher during April‐July, 2020. Thematic analysis was used to identify common themes using an inductive approach.
Results
Six themes emerged. (1) Experience of diagnosis. This theme included stories of delays in the system, self‐awareness of signs and symptoms and relief of being diagnosed. (2) ‘Shame, shame, shame’. Experiences of prejudices and discrimination from health professionals, the lack of understanding of cirrhosis among health professionals, and stories about alcohol cessation and counselling around alcohol cessation. (3) Health literacy. Participants’ understanding of cirrhosis was variable. While the importance of knowledge was recognised, ‘what works for someone might not work for others’. Several patients partnered with their support persons and clinicians to bridge the health literacy gap. (4) Sources of support included family and friends, transport facilities, health professionals and peers. (5) Positive and negative aspects of communication and patient consultation were discussed. (6) Psychosocial counselling to ‘look after the caring side’. The need for more mental health care services was raised.
Conclusion
Barriers related to poor health literacy, stigma and lack of practical and emotional support, and issues with communication and patient consultation, may lead to inequitable access to cirrhosis care and treatment for Indigenous Australians.
Relevance to clinical practice
Gaining knowledge of the experiences of Indigenous Australians with cirrhosis is important for providing patient‐centred and culturally appropriate care. Liver specialist nurses have an important role in bridging the health literacy gap and in supporting Indigenous patients and families.
In the present work we study the concepts of shadowing and chain recurrence in the setting of linear dynamics. We prove that shadowing and finite shadowing always coincide for operators on Banach ...spaces, but we exhibit operators on the Fréchet space H(C) of entire functions that have the finite shadowing property but do not have the shadowing property. We establish a characterization of mixing for continuous maps with the finite shadowing property in the setting of uniform spaces, which implies that chain recurrence and mixing coincide for operators with the finite shadowing property on any topological vector space. We establish a characterization of dense distributional chaos for operators with the finite shadowing property on Fréchet spaces. As a consequence, we prove that if a Devaney chaotic (resp. a chain recurrent) operator on a Fréchet space (resp. on a Banach space) has the finite shadowing property, then it is densely distributionally chaotic. We obtain complete characterizations of chain recurrence for weighted shifts on Fréchet sequence spaces. We prove that generalized hyperbolicity implies periodic shadowing for operators on Banach spaces. Moreover, the concepts of shadowing and periodic shadowing coincide for unilateral weighted backward shifts, but these notions do not coincide in general, even for bilateral weighted shifts.
In this work, we demonstrate the first example of fully printed carbon nanomaterials on paper with unique features, aiming the fabrication of functional electronic and electrochemical devices. Bare ...and modified inks were prepared by combining carbon black and cellulose acetate to achieve high-performance conductive tracks with low sheet resistance. The carbon black tracks withstand extremely high folding cycles (>20 000 cycles), a new record-high with a response loss of less than 10%. The conductive tracks can also be used as 3D paper-based electrochemical cells with high heterogeneous rate constants, a feature that opens a myriad of electrochemical applications. As a relevant demonstrator, the conductive ink modified with Prussian-blue was electrochemically characterized proving to be very promising toward the detection of hydrogen peroxide at very low potentials. Moreover, carbon black circuits can be fully crumpled with negligible change in their electrical response. Fully printed motion and wearable sensors are additional examples where bioinspired microcracks are created on the conductive track. The wearable devices are capable of efficiently monitoring extremely low bending angles including human motions, fingers, and forearm. Here, to the best of our knowledge, the mechanical, electronic, and electrochemical performance of the proposed devices surpasses the most recent advances in paper-based devices.
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