Ionomer Films Impact on The Structure, Flow Regime, and The Wettability of The Catalyst Layer of PEMFC

Percolation testing and contact angle measurements have been used to investigate the role of relative humidity on structure, mass transport, and wettability of a PEM fuel cell catalyst layer and membrane. Four samples were tested, two catalyst layers and two membranes. Structure and mass transport changes in the catalyst layers resulting from RH changes were studied in terms of percolation pressure. A clear change in the structure between low and high RH conditioning was observed. Relative humidity (RH) cycling also impacted percolation pressures with an indication of catalyst layer cracking. In addition, RH effect on wettability of both catalyst layers and membranes was studied by measuring contact angles of sessile drops.

Responses of the zooplankton community to the formation of a small reservoir on the Caveiras River, southern Brazil

We investigated changes in the species richness, abundance, and composition of the zooplankton community in response to the formation of a small reservoir in the Caveiras River, southern Brazil. Zooplankton were collected using a motor-pump and a plankton net (68 μm mesh), with 600 L of water filtered per sample. Sampling occurred during the pre- (April, August, and December 2011) and post-impoundment (July and October 2013, and January 2014) phases of the Caveiras River. We identified 86 taxa in this study, and rotifers were the predominant group. The species richness and abundance of the zooplankton increased after the filling of the reservoir. Furthermore, the zooplankton community showed a clear change in the species composition between the phases before and after the formation of the reservoir, with the emergence of typical planktonic species. Changes in the structure of the zooplankton community were related to changes in limnological characteristics due to the impoundment of the river, mainly in the availability of food and in the concentration of nutrients.

EP.WE.561The impact of COVID-19 on infra-inguinal revascularisation in patients with symptomatic peripheral occlusive arterial disease

Introduction Standard Operating Procedures were revised in response to the Covid-19 pandemic. There are descriptions from across Europe of increased rates of major extremity amputation. We have explored practice in a regional vascular unit serving two Health Boards in Scotland with specific reference to infra-inguinal revascularisation for patients with symptomatic peripheral occlusive arterial disease. Methods A retrospective review of the administrative theatre database was performed. Pre-Covid (1st April–July 31st 2019) and peri-Covid (1st April-31st July 2020) periods were examined and index cases identified. Practice and outcomes were examined. Results There was a 50% reduction in scheduled theatre sessions during the peri-Covid period. There were 100 procedures performed pre-Covid and 71 procedures performed during the peri-Covid period. The patient demographics were comparable – mean age 68-years with a male to female ratio of 1.6:1. Intervention for chronic limb threatening ischaemia was much more common in the peri-Covid period than in the pre-Covid period (94% versus 64% respectively). There was a clear change in anaesthetic practice with regional anaesthesia more commonly performed in the peri-Covid period (49% versus 12% respectively). There was no difference in the types of revascularisation performed. The 30-day mortality in the peri-Covid period was less than in the pre-Covid period (3% vs 1.4%). Conclusion The Covid-19 pandemic created imperatives that necessitated re-structure of service. Despite a reduction in theatre access we have managed to maintain a limb salvage service for patients with chronic limb threatening ischaemia.

A newly developed method based on surface physicochemical proprieties, for measuring the maturation level of olive fruit

The maturation process is an important determining factor to initiate the fermentation process in olive fruit. Level of maturation classically determined by the color of the olive fruit. In this study, we aim to develop a measurable criterion based on physicochemical properties and surface roughness of two important olive varieties grown in Morocco. The hydrophobic/hydrophilic properties and the electron donor-acceptor character of the olives were calculated. The obtained results showed a very clear change in the electron donor character and the surface roughness of the two studied varieties. This change depended on the degree of maturity and the nature of the cultivar. The electron donor character decreased (two times) with an increasing degree of maturity for the Arbequina, contrary to the Picholine variety, which showed a significant increase (4 times). Surface roughness increased 10 times for the Arbequina and decreased 5 times for the Picholine as maturity progressed from the green to the black stage. These findings may be useful in the management/prediction of the process of table olive fermentation.

The (mis)conception of average Quaternary conditions

The concept of Quaternary average conditions has gained popularity over the past few decades, especially with studies of long-term landscape evolution. In this paper, we critically assess this concept by analyzing the marine isotope record (LR04 δ18O stack) relative to the Quaternary. This shows that the frequency and amplitude of climate glacial-interglacial cycles are not constant throughout the Quaternary, with a clear change during the Middle Pleistocene Transition (MPT), and that many minor oscillations exist within each cycle. For this reason, the identification of pre- and post-MPT most-frequent and, cumulatively, longest-lasting (rather than average) conditions is recommended. The most-frequent pre-MPT δ18O value of 3.725 ± 0.025‰ last occurred during 11.31–11.47 ka, while the most-frequent post-MPT δ18O value of 4.475 ± 0.025‰ last occurred during 14.81–15.04 ka. However, many other δ18O values were almost as frequent throughout the Quaternary and we present geomorphological reasons as to why it is unlikely that the present-day landscape reflects Quaternary average or, indeed, most-frequent conditions. Collectively, our results indicate that extreme caution should be taken when attempting to infer long-term landscape evolution processes (including the buzzsaw hypothesis) based on average Quaternary conditions.

Evaluating the Effect of a Brewery By-Product as Feed Supplementation on the Quality of Eggs by Means of a Human Panel and E-Tongue and E-Nose Analysis

The objective of our research was to evaluate the possible alteration of the organoleptic properties of eggs produced by hens (Lohmann Brown-Classic) fed with diets containing different doses of an industrial by-product enriched with organic zinc (Zincoppyeast, ZP): Control 0%, ZP 2.5%, and ZP 5.0%. Eggs were collected after 30 days (batch 1) and 60 days (batch 2) of feeding with the experimental diets and subjected to chemical, microbiological, human sensory, e-nose, and e-tongue analyses. There was no significant difference among the microbiological status of eggs of the three groups, but there were significant differences (p < 0.05) in the fat (9.5% vs. 9.3%) and protein contents (12.7% vs. 13.4%) of the Control and ZP 5.0% groups, respectively. Human sensory analysis showed no clear change in the organoleptic characteristics of the eggs. Using linear discriminant analysis (LDA), the e-tongue could recognize the three groups of eggs in batch 1 and batch 2 with 95.9% and 100% accuracy and had a prediction accuracy of 64.8% and 56.2%, respectively. When the eggs were incubating at 50 °C or 80 °C before the e-nose analysis, the groups of eggs could be recognized with 98.0% and 82.7% accuracy, and predicted with 68.5% and 62.2% accuracy, respectively, using principal component analysis-based discriminant analysis (PCA–DA). The aroma compounds and respective sensory descriptors showing changes among the different groups of eggs (batch, storage, and feeding) were identified based on the e-nose analysis. The supplementation of laying hens’ feed with the investigated industrial by-product can be applied without any substantial effect on egg quality, which can, however, be detected with advanced analytical methods.

A KCNC1 mutation in Epilepsy of Infancy with Focal Migrating Seizures produces functional channels that fail to be regulated by phosphorylation

Channelopathies caused by mutations in genes encoding ion channels generally produce a clear change in channel function. Accordingly, mutations in KCNC1, which encodes the voltage-dependent Kv3.1 potassium channel, result in Progressive Myoclonus Epilepsy as well as other Developmental and Epileptic Encephalopathies, and these have been shown to reduce or fully abolish current amplitude. One exception to this is the mutation A513V Kv3.1b, located in the cytoplasmic C-terminal domain of the channel protein. This de novo variant was detected in a patient with Epilepsy of Infancy with Focal Migrating Seizures (EIFMS) but no difference could be detected between A513V Kv3.1 current and that of wild type Kv3.1. Using both biochemical and electrophysiological approaches, we have now confirmed that this variant produces functional channels but find that the A513V mutation renders the channel completely insensitive to regulation by phosphorylation at S503, a nearby regulatory site in the C-terminus. In this respect, the mutation resembles those in another channel, KCNT1, which are the major cause of EIFMS. Because the amplitude of Kv3.1 current is constantly adjusted by phosphorylation in vivo, our findings suggest that loss of such regulation contributes to EIFMS phenotype and emphasize the role of channel modulation for normal neuronal function.

High-temperature diffraction experiments and phase diagram of ZrO2 and ZrSiO4

High-temperature X-ray diffraction (XRD) experiments up to T = 2710 °C have been performed on ZrSiO4 and ZrO2 powders, using the container-less levitation technique. A two-dimensional imaging plate (IP) detector was used for short-time observation. The diffraction data in a wide area was projected in one dimension. The unit cell parameters, thermal expansions, and c/a ratios for ZrSiO4 (space group I41/amd and Z = 4), tetragonal ZrO2 (space group P42/nmc and Z = 2) and cubic ZrO2 (space group F m 3 ‾ m $Fm3&#x203e;{}m$ and Z = 4) were measured to understand the high-temperature behaviors. The transition temperature between tetragonal and cubic ZrO2 was specified to be between 2430 and 2540 °C. The pre-transitional behavior was observed around 2200 °C. As no clear change in unit cell volume is evident, the phase boundary between the tetragonal and the cubic phase has been shown to be a positive slope. The ZrO2 and ZrO2–SiO2 phase diagrams are proposed based on the chemical composition and the crystal structure.

Stewardship of Digital Archaeological Data in Greece: a landscape of fragmentation

This article provides an overview of the current situation in Greece regarding digital archaeological data stewardship. A brief chronicle of Greek archaeology sets the scene for a better understanding of the present situation. Greek archaeology is supervised by the Ministry of Culture and Sports, with the Archaeological Service as the central organisation in charge of antiquities. However, archaeological data resulting from archaeological fieldwork are produced by several other entities. This article presents the policies governing both physical and digital documentation archives. It introduces the current practices for archaeological data preservation and the relevant digital infrastructures, attempting to showcase the existing environment. We categorise prevailing problems on three levels, all based on the fact that digital and open access arrived recently in a well-established environment formed gradually over almost two centuries. Even so, fragmentation and variation would be the proper terms to describe the status of the stewardship of digital archaeological data in Greece. Our review shows that there is substantial effort directed towards digital archaeological data stewardship and accessibility by all stakeholders within the archaeological sector. Finally, we add a few thoughts and suggestions, and indicate the need to generate a network that could take steps towards more inclusive strategies within digital data stewardship. The key to leveraging change is raising awareness about data sustainability and reuse, and the COVID-19 outbreak indicates a clear change in mentality in this direction, since open access resources have begun to be key to education and research conducted in Greece.

Social Housing in a Competitive City : Exploring the Evolution and Impacts of Changes in Toronto's Social Housing System

This paper seeks to explore the evolution of social housing policy in Toronto as well as provide insight into new "revitalization" initiatives. After identifying key trends in social housing, it compares these insights with the opinions expressed in interviews with key informants in Toronto's housing sector. The implications of this research reveal several important findings. First, in regard to the supply of social housing, it is clear that Toronto is in the midst of a housing crisis. Secondly, despite significant research that casts doubts on the proposed benefits of new "revitalization" schemes, key informants in the sector appear to have accepted the current agenda of the social housing sector. The entrenchment of such opinions, it is argued, marks a clear change from past priorities in social housing and also contributes to the overshadowing of the dismantling of the social housing sector at a time when it is most needed.