An estimate of size of copper nanoparticles levitating over the melt surface using the measurements of spectral reflectance

A strong decrease in normal reflectance of a probe laser beam of 660 nm wavelength reflected from the surface of copper sample just after the beginning of the sample melting in a rarefied argon atmosphere has been observed recently by the authors. A similar time dependence of the reflectance is obtained in the laboratory experiments of the present paper at the wavelengths of 532 nm. The additional spectral measurements enable the authors to estimate the size of condensed nanoparticles levitating over the copper melt.

Gender-specific analysis of the authors and the editorial board of Naunyn–Schmiedeberg’s Archives of Pharmacology from 2000 to 2020

Motivated by the worldwide debate on gender equality, we analyzed the gender structure of the authors and the editorial board of Naunyn–Schmiedeberg’s Archives of Pharmacology. We wrote an algorithm to assign authors’ first names to a gender to determine the gender distribution of publications. We evaluated publications from German research institutes from 2000 to 2020. This resulted in a data set of 2929 authors. We could assign a first name to almost all authors. The percentage of female authors increased until 2008, but thereafter stagnated at around 30%. The position of senior author is far less often held by women (around 15%). Even though multiple political measures were implemented to increase the female participation, our analysis has shown no increase regardless. We also observed a strong decrease in German authorship (both male and female) since 2000. In the editorial board and for advisory editors, there has been a substantial increase in the proportion of women since 2016 as the result of appointments by the editor-in-chief. We discuss the strengths and limitations of our study in context with the literature and current developments in society and science and methodological pitfalls of studies in this field. More research is required to obtain a full picture of gender structure in science and to be able to properly interpret the data.

Different light and temperature requirements for survival and growth in three species of Kallymeniaceae (Rhodophyta) from the Mediterranean Sea

Laboratory experiments have shown that light and temperature requirements are critical determining factors for thallus survival and growth of three Mediterranean Kallymeniaceae (Rhodophyta): Verlaquea lacerata, Croisettea requienii, and Meredithia microphylla, and explain their current bathymetric and habitat distribution. Verlaquea lacerata is annual and survived more than 1.5 years in culture, while C. requienii and M. microphylla are perennial and survived more than four and nine years in culture, respectively. The maximum survival was observed at 20–50 µmol photon m−2 s−1 and 10 and 12 °C within an 8:16 h light:dark regime for the three species, while a strong decrease in survival was observed at temperatures of 24 and 26 °C, indicating a weak tolerance to warming temperatures in the Mediterranean. The maximum value of the rate of daily marginal extension per initial surface area was similar in the three species: 0.017 day−1 for V. lacerata (10 °C/8:16 h light:dark regime/10 µmol photon m−2 s−1), 0.021 day−1 for C. requienii (18 °C/14:10 h light:dark regime/10 µmol photon m−2 s−1), and 0.017 day−1 for M. microphylla (12 °C/8:16 h light:dark regime/20 µmol photon m−2 s−1). The experiments permitted the establishment of culture conditions for the target species, and the successful culture of marginal fragments indicates the possibility of indefinitely maintaining the species in the laboratory for bioconservation purposes.

On the stability of microwave-fabricated SERS substrates – chemical and morphological considerations

The stability of surface-enhanced Raman spectroscopy (SERS) substrates in different organic solvents and different buffer solutions was investigated. SERS substrates were fabricated by a microwave-assisted synthesis approach and the morphological as well as chemical changes of the SERS substrates were studied. It was demonstrated that the SERS substrates treated with methanol, ethanol, or N,N-dimethylformamide (DMF) were comparable and showed overall good stability and did not show severe morphological changes or a strong decrease in their Raman activity. Toluene treatment resulted in a strong decrease in the Raman activity whereas dimethyl sulfoxide (DMSO) treatment completely preserved or even slightly improved the Raman enhancement capabilities. SERS substrates immersed into phosphate-buffered saline (PBS) solutions were observed to be rather instable in low and neutral pH buffer solutions. Other buffer systems showed less severe influences on the SERS activity of the substrates and a carbonate buffer at pH 10 was found to even improve SERS performance. This study represents a guideline on the stability of microwave-fabricated SERS substrates or other SERS substrates consisting of non-stabilized silver nanoparticles for the application of different organic solvents and buffer solutions.

Evolution of Mitochondrial-Derived Peptides, Humanin and MOTSc and Changes in Insulin Sensitivity During Early Gestation

Aims: To study the evolution of mitochondrial-derived peptides (MDPs) and their relationship with changes in insulin sensitivity from the early stages of pregnancy.Methods: MDPs (humanin and MOTSc) were assessed in the first and second trimesters of gestation in 28 pregnant women with gestational diabetes mellitus (GDM) and a subgroup of 45 matched pregnant women without GDM. Insulin resistance (IR) was defined as a HOMA-IR index ≥70 percentile.Results: We observed a significant reduction in both humanin and MOTSc levels from the first to the second trimesters of pregnancy. After adjusting for BMI we did not find an association between low levels of humanin and the occurrence of a high HOMA-IR index (adjusted OR= 2.63 and 3.14, linear p-trend 0.260 and 0.175, respectively). Regarding MOTSc, an association was found only for the second trimester: adjusted OR=7.68 (95% CI 1.49-39.67), linear p-trend=0.012. No significant associations were observed in humanin change with insulin resistance throughout pregnancy, but changes in MOTSc levels were significantly associated with HOMA-IR index: adjusted OR 3.73 (95% CI 1.03-13.50).Conclusions: MOTSc levels, especially a strong decrease from the first to the second trimester of gestation, may be involved in increasing insulin resistance during early gestation.CLINICAL TRIAL REGISTRATIONNot applicable

Maps, trends, and temperature sensitivities—phenological information from and for decreasing numbers of volunteer observers

Phenology serves as a major indicator of ongoing climate change. Long-term phenological observations are critically important for tracking and communicating these changes. The phenological observation network across Germany is operated by the National Meteorological Service with a major contribution from volunteering activities. However, the number of observers has strongly decreased for the last decades, possibly resulting in increasing uncertainties when extracting reliable phenological information from map interpolation. We studied uncertainties in interpolated maps from decreasing phenological records, by comparing long-term trends based on grid-based interpolated and station-wise observed time series, as well as their correlations with temperature. Interpolated maps in spring were characterized by the largest spatial variabilities across Bavaria, Germany, with respective lowest interpolated uncertainties. Long-term phenological trends for both interpolations and observations exhibited mean advances of −0.2 to −0.3 days year−1 for spring and summer, while late autumn and winter showed a delay of around 0.1 days year−1. Throughout the year, temperature sensitivities were consistently stronger for interpolated time series than observations. Such a better representation of regional phenology by interpolation was equally supported by satellite-derived phenological indices. Nevertheless, simulation of observer numbers indicated that a decline to less than 40% leads to a strong decrease in interpolation accuracy. To better understand the risk of declining phenological observations and to motivate volunteer observers, a Shiny app is proposed to visualize spatial and temporal phenological patterns across Bavaria and their links to climate change–induced temperature changes.

Importance of pH in Synthesis of pH-Responsive Cationic Nano- and Microgels

While cationic microgels are potentially useful for the transfection or transformation of cells, their synthesis has certain drawbacks regarding size, polydispersity, yield, and incorporation of the cationic comonomers. In this work, a range of poly(N-isopropylacrylamide) (PNIPAM) microgels with different amounts of the primary amine N-(3-aminopropyl)methacrylamide hydrochloride (APMH) as the cationic comonomer were synthesized. Moreover, the pH-value during reaction was varied for the synthesis of microgels with 10 mol% APMH-feed. The microgels were analyzed by means of their size, thermoresponsive swelling behavior, synthesis yield, polydispersity and APMH-incorporation. The copolymerization of APMH leads to a strong decrease in size and yield of the microgels, while less than one third of the nominal APMH monomer feed is incorporated into the microgels. With an increase of the reaction pH up to 9.5, the negative effects of APMH copolymerization were significantly reduced. Above this pH, synthesis was not feasible due to aggregation. The results show that the reaction pH has a strong influence on the synthesis of pH-responsive cationic microgels and therefore it can be used to tailor the microgel properties.

Consequences of nutrient load reductions for carbon and alkalinity dynamics within the region of freshwater influence of River Elbe

<p>Since the early eighties of the 20<sup>th</sup> century nitrogen and phosphorus loads of the River Elbe, a river entering the North European Shelf at the southeastern coast, have decreased by a factor of about four. This resulted in a reduction of the eutrophication status in the adjacent German Bight and the coastal waters west of Denmark. In addition, benthic carbon and alkalinity pools have changed due to 1- changed carbon loads and, 2- changed decay pathways of benthic organic carbon.</p><p>We investigate the consequences of observed nutrient and organic loads by rivers with a 3D-biogeochemical model including a 3D-early diageneses model within the sediment for the time 1979 - 2014.   </p><p>The results show a strong decrease of benthic carbon rather due to decreasing nutrient loads and subsequent autochthonous biological production than changes in organic loads. The export of inorganic carbon from the sediment is related to the magnitude of benthic organic carbon and cannot explain the strong decrease of the benthic POC pool. During the time until the early nineties aerobic degradation increases, whereas denitrification and sulfate reduction as organic matter degradation pathway decreases.</p><p>Alkalinity production due to benthic organic matter degradation decreases over the first half of the investigated time interval and keeps constant during the second half. Denitrification and sulfate reduction dominate the mechanisms decreasing the alkalinity export. Benthic nitrification consuming alkalinity strongly increases during the first half of the time dampening the decrease of alkalinity export.</p>

A Study on the Effect of Flow Unsteadiness on the Yield of a Chemical Reaction in a T Micro-Reactor

Despite the very simple geometry and the laminar flow, T-shaped microreactors have been found to be characterized by different and complex steady and unsteady flow regimes, depending on the Reynolds number. In particular, flow unsteadiness modifies strongly the mixing process; however, little is known on how this change may affect the yield of a chemical reaction. In the present work, experiments and 3-dimensional numerical simulations are carried out jointly to analyze mixing and reaction in a T-shaped microreactor with the ultimate goal to investigate how flow unsteadiness affects the reaction yield. The onset of the unsteady asymmetric regime enhances the reaction yield by more than 30%; however, a strong decrease of the yield back to values typical of the vortex regime is observed when the flow undergoes a transition to the unsteady symmetric regime.

Mining Google and Apple mobility data: temporal anatomy for COVID-19 social distancing

We employ the Google and Apple mobility data to identify, quantify and classify different degrees of social distancing and characterise their imprint on the first wave of the COVID-19 pandemic in Europe and in the United States. We identify the period of enacted social distancing via Google and Apple data, independently from the political decisions. Our analysis allows us to classify different shades of social distancing measures for the first wave of the pandemic. We observe a strong decrease in the infection rate occurring two to five weeks after the onset of mobility reduction. A universal time scale emerges, after which social distancing shows its impact. We further provide an actual measure of the impact of social distancing for each region, showing that the effect amounts to a reduction by 20–40% in the infection rate in Europe and 30–70% in the US.