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Activating pretreatments are used to tune surface composition and structure of bimetallic-alloy catalysts. Herein, the activation-induced changes in material properties of a nanoporous Ag0.03Au0.97 alloy and their subsequent evolution under steady-state CH3OH oxidation conditions are investigated. Activation using O3 results in AgO and Au2O3, strongly enriching the near-surface region in Ag. These oxides reduce in the O2/CH3OH mixture, yielding CO2 and producing a highly Ag-enriched surface alloy. At the reaction temperature (423 K), Ag realloys gradually with Au but remains enriched (stabilized by surface O) in the top few nanometers, producing methyl formate selectively without significant deactivation. At higher temperatures, bulk diffusion induces sintering and Ag redistribution, leading to a loss of activity. These findings demonstrate that material properties determining catalytic activity are dynamic and that metastable (kinetically trapped) forms of the material may be responsible for catalysis, providing guiding principles concerning the activation of heterogeneous catalysts for selective oxidation.

Activating pretreatments are used to tune surface composition and structure of bimetallic-alloy catalysts. Herein, the activation-induced changes in material properties of a nanoporous Ag0.03Au0.97 alloy and their subsequent evolution under steady-state CH3OH oxidation conditions are investigated. Activation using O3 results in AgO and Au2O3, strongly enriching the near-surface region in Ag. These oxides reduce in the O2/CH3OH mixture, yielding CO2 and producing a highly Ag-enriched surface alloy. At the reaction temperature (423 K), Ag realloys gradually with Au but remains enriched (stabilized by surface O) in the top few nanometers, producing methyl formate selectively without significant deactivation. At higher temperatures, bulk diffusion induces sintering and Ag redistribution, leading to a loss of activity. These findings demonstrate that material properties determining catalytic activity are dynamic and that metastable (kinetically trapped) forms of the material may be responsible for catalysis, providing guiding principles concerning the activation of heterogeneous catalysts for selective oxidation.

Although there are various theories regarding the development of mathematical thinking in early childhood, there is a gap in the application of didactic strategies to enhance its development. The research was aimed at analyzing the essential characteristics of the categories Development of Mathematical Thought and Didactic Strategies, identifying and interpreting the didactic strategies used by nursery educators to develop mathematical thinking in girls and boys, aged between 2 and 4 years, in Chilean classrooms. The sample consisted of 7 key informants, who practice their profession in different regions of Chile. A qualitative method with an interpretive approach was used, which allowed describing, categorizing and theorizing about the realization of the aforementioned constructs. The conclusions highlight the importance of designing didactic strategies that favor the development of mathematical thinking in girls and boys, which is based on the experimentation and interaction of collective, playful and interactive activities that are coupled with pedagogical support. The foregoing makes it possible for the teaching and learning of mathematics to move away from traditional methods, and allow its development as a future thought.

Catalytic pathways of plastic waste valorization to lubricants are attractive avenues to foster circular economy. Tuning of catalyst electronic properties allows to significantly improve its activity due to boosted hydrogen storage on the surface.

Two factors are crucial for the effective operation of modern-day smart services: Initially, IoT-enabled technologies have to capture and combine huge amounts of data on data subjects. Then, all these data have to be processed exhaustively by means of techniques from the area of big data analytics. With regard to the latter, thorough data refinement in terms of data cleansing and data transformation is the decisive cornerstone. Studies show that data refinement reaches its full potential only by involving domain experts in the process. However, this means that these experts need full insight into the data in order to be able to identify and resolve any issues therein, e.g., by correcting or removing inaccurate, incorrect, or irrelevant data records. In particular for sensitive data (e.g., private data or confidential data), this poses a problem, since these data are thereby disclosed to third parties such as domain experts. To this end, we introduce SMARTEN, a sample-based approach towards privacy-friendly data refinement to smarten up big data analytics and smart services. SMARTEN applies a revised data refinement process that fully involves domain experts in data pre-processing but does not expose any sensitive data to them or any other third-party. To achieve this, domain experts obtain a representative sample of the entire data set that meets all privacy policies and confidentiality guidelines. Based on this sample, domain experts define data cleaning and transformation steps. Subsequently, these steps are converted into executable data refinement rules and applied to the entire data set. Domain experts can request further samples and define further rules until the data quality required for the intended use case is reached. Evaluation results confirm that our approach is effective in terms of both data quality and data privacy.

BackgroundEntamoeba gingivalis (E. gingivalis) is an anaerobic protozoan that is strongly associated with inflamed periodontal pockets. It is able to invade the mucosal epithelium of the human host, where it can feed on epithelial cells and elicit a severe innate immune response. Unlike other Entamoeba species, it is considered that E. gingivalis cannot form cysts, because it is a non-infectious protozoan. The lack of encystation capability would make it susceptible to periodontal treatment. However, it is not clear how the human host becomes infected with E. gingivalis trophozoites. We investigated the ability of E. gingivalis to encapsulate in response to an unfavorable environment in vitro.MethodsDifferent strains of E. gingivalis, isolated from inflamed periodontal pocket samples, were cultured for 8 days in the presence or absence of the antimicrobials amoxycillin and metronidazole. To reveal cyst formation, we investigated the morphology and ultrastructure of the amoeba by light, fluorescence, transmission and scanning electron microscopy. We also used the fluorescent dye calcofluor white M2R to demonstrate chitin present in the cyst wall.ResultsWe observed exocysts and an intra-cystic space separating the encapsulated trophozoite from the environment. Remarkably, cysts showed a smooth surface, polygonal edges and smaller size compared to free-living trophozoites. In addition, encapsulated trophozoites that detached from the cyst wall had a dense cytoplasma without phagocytic vesicles. The cyst walls consisted of chitin as in other Entamoba species. The encapsulated trophozoids were mononuclear after antibioticinduced encapsulation.DiscussionWe conclude that E. gingivalis cyst formation has significant implications for dissemination and infection and may explain why established treatment approaches often fail to halt periodontal tissue destruction during periodontitis and peri-implantitis.

Abstract Background Current incidence estimates of SARS-CoV-2 in Germany rely to a large extent on case notifications. However, the large number of mild or asymptomatic infections is likely to result in underestimation. Population-based studies can provide valid estimates of the SARS-CoV-2 incidence and thus support health authorities to monitor the epidemiological situation and to initiate, maintain, strengthen or relax effective countermeasures. Methods This study was conducted in Cologne, Germany. Six-thousand randomly drawn Cologne residents, 18 years of age or older, were contacted by mail in March 2021. Study envelopes contained a kit for self-administered saliva sample and access details to a questionnaire on sociodemographic characteristics, previous positive SARS-CoV-2 RT-qPCR and completed COVID-19 vaccinations. Participants were again invited for a second round in June 2021, while those who declined participation were replaced by additional randomly drawn Cologne residents in order to reach a total of 6000 potential participants again. The saliva samples were sent to the laboratory by mail and tested for SARS-CoV-2 using RT-qPCR. The incidence estimates were adjusted for sensitivity and specificity of the test procedure and compared with the official numbers of new SARS-CoV-2 cases in the adult Cologne population. Results The first surveillance round in March 2021 (response rate: 34.08%, N = 2045) showed a SARS-CoV-2 seven-day incidence of 85 cases per 100,000 adult Cologne residents (95% CI: 9 to 319). In the same period, the officially registered cases were 125 per 100,000. The second surveillance round in June 2021 (response rate: 36.53%, N = 2192) showed a seven-day incidence of 27 per 100,000 adult Cologne residents (95% CI: 1 to 142), while the official figures for newly registered SARS-CoV-2 cases in the same period were 15 per 100,000. Conclusions The incidence estimates do not indicate relevant underestimation of new SARS-CoV-2 infections based on case notification. Regular use of the surveillance method developed here may nevertheless complement the efforts of the health authorities to assess the epidemiological situation. Trial registration DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00024046 , Registered on 25 February 2021.

Abstract Background Mobile health apps (MHAs) may offer a mean to overcome treatment barriers in Borderline Personality Disorder (BPD) mental health care. However, MHAs for BPD on the market lack transparency and quality assessment. Methods European app stores were systematically searched, and two independent trained reviewers extracted relevant MHAs. Employed methods and privacy and security details documentation of included MHAs were extracted. MHAs were then assessed and rated using the German version of the standardized Mobile Application Rating Scale (MARS-G). Mean values and standard deviations of all subscales (engagement, functionality, aesthetics, information, and therapeutic gain) and correlations with user ratings were calculated. Results Of 2977 identified MHAs, 16 were included, showing average quality across the four main subscales (M = 3.25, SD = 0.68). Shortcomings were observed with regard to engagement (M = 2.87, SD = 0.99), potential therapeutic gain (M = 2.67, SD = 0.83), existing evidence base (25.0% of included MHAs were tested empirically), and documented privacy and security details. No significant correlations were found between user ratings and the overall total score of the MARS-G or MARS-G main subscales. Conclusions Available MHAs for BPD vary in quality and evidence on their efficacy, effectiveness, and possible adverse events is scarce. More substantial efforts to ensure the quality of MHAs available for patients and a focus on transparency, particularly regarding privacy and security documentation, are necessary.

AbstractObjectiveMethodsResultsConclusionAlthough the efficacy of mepolizumab in reducing exacerbations and oral corticosteroid (OCS) use in severe asthma is well-established, real-world long-term effectiveness data are limited. This study evaluated the real-world impact of mepolizumab treatment in patients with severe asthma over a 4-year follow-up period.This was a retrospective cohort study of patients with asthma initiating mepolizumab (index date: first claim, November 2015–September 2019) using the Merative MarketScan Commercial and Medicare Databases. Outcomes included asthma exacerbations, OCS use, and exacerbation-related healthcare resource utilization (HCRU) and costs, assessed 12-months pre-index (baseline) and annually during the 4-year follow-up period.Among 189 eligible patients, mean asthma exacerbation rate (AER) declined progressively from baseline during follow-up: AER decreased by 53.8% at Year 1 and 73.8% by Year 4 (p < 0.001). The annual OCS prescription rate reduced from baseline by 41.1% at Year 1 and 62.2% at Year 4 (p < 0.001). The proportion of patients with both no exacerbations and no OCS use progressively increased from 6.4% at baseline to 18.5% at Year 1 and 41.8% at Year 4. Exacerbation-related HCRU including inpatient, emergency room, and outpatient office visits decreased from baseline (9.0%, 21.7%, and 78.8%, respectively), at Year 1 (3.2%, 12.2%, and 49.2%), and Year 4 (0.0%, 4.8%, and 31.8%). Exacerbation-related healthcare costs declined from $4,635 at baseline to $1,487 at Year 1 and $217 at Year 4 (p < 0.001).Patients treated with mepolizumab demonstrated progressive and sustained long-term, real-world reductions in exacerbation frequency, OCS dependency, and exacerbation-related HCRU and costs over 4 years. [ABSTRACT FROM AUTHOR]

The field of memory studies rarely deals with commercial enterprises, which, as we argue in this article, play just as prominent a role in shaping collective memories as state actors or nongovernmental organizations. The aim of our study is therefore to discuss the role of private entrepreneurs and their businesses in the context of GDR memory. We focus on the privately run GDR Museum in Berlin and its best-selling products. Through the lens of the museum store, we analyze the exhibition, an iconic eggcup, and a book on the history of the GDR that has enjoyed sustained sales over a lengthy period. By tracing the intertwined distribution chains of these memory goods, we emphasize the importance of private entrepreneurs and their networks in the current German memory culture. We argue that economic interests and developments are just as important as political decisions and public institutions regarding the memory of the communist past. Thus memory studies should also focus on enterprises of memory by analyzing business data. This poses an empirical challenge that is worth tackling, since it broadens our understanding of current memory culture. [ABSTRACT FROM AUTHOR]

The review presents methods that are used frequently for multi-analytical study of fossil resins. The preliminary characterization relies on physical methods such as microhardness, density and fluorescence in UV light measurements. The spectroscopic methods: infrared spectroscopy, Raman spectroscopy, fluorescence spectroscopy are also presented in the paper. Besides that, the review also contains examples of the application of chromatographic methods: gas chromatography, thin layer chromatography, high-performance liquid chromatography, two-dimensional gas chromatography coupled to time-of-flight mass spectrometry as well as sample preparation methods for chromatographic studies such as pyrolysis. Additionally, thermal methods such as thermogravimetric analysis and differential scanning calorimetry also are covered by the review. Beside the examples of application, a detailed description with development history and perspective for further improvement are presented for each method. Moreover, fit-for-purpose assessment of each method is illustrated based on many examples from literature. The paper also contains examples of the application of multivariate statistical analysis and chemometric methods for comparing multiple properties of different fossil resin specimens for differentiation and classification purposes. [ABSTRACT FROM AUTHOR]

Due to its tendency to increase the power of engines, improving their reliability and operational efficiency, the compression ring in combustion engine pistons is embedded in a cast iron insert, which is subjected to the process of "alfining". This involves covering the insert with an Al–Si alloy, which increases the iron content. Research has shown that the β-Al5FeSi phases crystallizing in the area of the insert–piston connection are the main cause of an unstable connection between the silumin casting of the piston and the ring insert. Their unfavourable lamellar morphology and large dimensions are the main causes of weakening in the connection between the insert and the piston, resulting in an unacceptable number of defective products. It has also been found that up to approx. 0.59 wt.% Fe, the pore volume fraction is very small (up to 3%), and there is no correlation. However, after exceeding this value, both the volume fraction of the β-Al5FeSi phase and the number of pores increase monotonically to values of approximately 18% and 14%, respectively, and the correlation between the examined features is statistically significant. These results were compared with known theories of the influence of iron on the porosity of Al–Si alloys, showing that the precipitates of the β-Al5FeSi phase are more important in the porosity fraction than the two-layer oxide films called "bifilms". This research was carried out and verified under industrial conditions in one of the largest piston foundries (Federal-Mogul Gorzyce sp. z o.o., F-MG) on a separate line intended for alfining ring inserts intended for combustion pistons. [ABSTRACT FROM AUTHOR]

Biomonitoring studies are most often used in short-term study periods to quickly obtain information on the state/quality of the environment and its pollution levels. Performing long-term surveys involves a prolonged wait for the result and is therefore not often used and is rather associated with classical air quality monitoring. The aim of this study was to evaluate atmospheric air pollution by selecting 16 elements and 16 polycyclic aromatic hydrocarbons conducted as part of a 12-month ‘moss-bag’ technique of an active biomonitoring method with the use of three moss species: Pleurozium schreberi, Sphagnum fallax, and Dicranum polysetum. All analytes were determined by inductively coupled plasma mass spectrometry (ICP-MS) and gas chromatography–mass spectrometry (GC-MS). As a result of the experiment, it was found that the concentrations of all elements increased with time of exposure. The total sum of them in D. polysetum moss was 30% and 60% more than in P. schreberi and S. fallax, respectively, which allows us to consider this species’ broader use in active biomonitoring. For PAHs analysis, the best biomonitor in time was P. schreberi, which accumulated 25% and 55% more than S. fallax and D. polysetum, respectively. In this one-year study, most organic compounds accumulated between 5 and 6 months of exposure, depending on the species. Given the low-cost nature of active biomonitoring, it should be concluded that mosses could be used in long-term monitoring of the quality of the atmospheric aerosol in terms of element and organic compound concentration in air.

For more than five decades, research has been conducted at Ny-Ålesund, in Svalbard, Norway, to understand the structure and functioning of High-Arctic ecosystems and the profound impacts on them of environmental change. Terrestrial, freshwater, glacial and marine ecosystems are accessible year-round from Ny-Ålesund, providing unique opportunities for interdisciplinary observational and experimental studies along physical, chemical, hydrological and climatic gradients. Here, we synthesize terrestrial and freshwater research at Ny-Ålesund and review current knowledge of biodiversity patterns, species population dynamics and interactions, ecosystem processes, biogeochemical cycles and anthropogenic impacts. There is now strong evidence of past and ongoing biotic changes caused by climate change, including negative effects on populations of many taxa and impacts of rain-on-snow events across multiple trophic levels. While species-level characteristics and responses are well understood for macro-organisms, major knowledge gaps exist for microbes, invertebrates and ecosystem-level processes. In order to fill current knowledge gaps, we recommend (1) maintaining monitoring efforts, while establishing a long-term ecosystem-based monitoring programme; (2) gaining a mechanistic understanding of environmental change impacts on processes and linkages in food webs; (3) identifying trophic interactions and cascades across ecosystems; and (4) integrating long-term data on microbial, invertebrate and freshwater communities, along with measurements of carbon and nutrient fluxes among soils, atmosphere, freshwaters and the marine environment. The synthesis here shows that the Ny-Ålesund study system has the characteristics needed to fill these gaps in knowledge, thereby enhancing our understanding of High-Arctic ecosystems and their responses to environmental variability and change.

Resumo A produção de ceramida ocorre em todo o corpo e desempenha um papel importante na manutenção da fisiologia normal. No entanto, os níveis de ceramidas são alterados em estados de doença, principalmente durante o desenvolvimento de diabetes e dislipidemia. A produção de ceramidas também está associada à instabilidade das placas ateroscleróticas. Estudos recentes revelam que pacientes com doença arterial coronariana instável apresentam níveis plasmáticos aumentados de ceramidas (principalmente C16, C18 e C24:1). Atualmente, são consideradas biomarcadores emergentes nas doenças cardiovasculares, sendo utilizadas na predição de instabilidade da placa aterosclerótica e eventos cardiovasculares adversos de forma independente aos fatores de risco tradicionais. Com o objetivo de descrever e discutir o papel das ceramidas na estratificação das doenças cardiovasculares, o desenvolvimento desta revisão narrativa contextualiza a importância desse biomarcador no cenário atual da cardiologia.