The proportion of co-authored research articles has risen markedly in recent decades

The proportion of multi-authored papers in the social sciences has risen steadily over recent decades. But what are the reasons behind such a marked increase? Lukas Kuld and John O'Hagan consider a number of explanations, from increased academic specialisation and more affordable communication and travel, to the pressures of publication and an inclination among authors to spread the risks of research assessment across a number of articles. These trends also pose an interesting academic policy question: to what extent should academic hiring and promotional bodies apply a discount for articles with many authors

Möglichkeiten der Detektionsrate neonataler Sepsiserreger im Rahmen mikrobiologischer Diagnostik bei den Müttern - real world data

Objective: The aim of this study was to identify the rate of detection of neonatal sepsis pathogens in maternal micobriological smears. Studydesign: This is a retrospective study conducted at a Level 1 perinatal center in the context of routine care from 2014 to 2019. For all premature infants and neonates with neonatal sepsis, the neonatal and maternal microbiological findings were examined to see if there was a match. Results: During the study period, a total of 948 premature or newborn infants were identified as having a neonatal infection. Among all of the premature or newborn infants, 209 (22 %) met the diagnostic criteria for neonatal sepsis; of these, 157 were premature births and 52 were full-term births. We evaluated the microbiological findings for these 209 mother and child pairs. No pathogens were detected in 27 out of 157 mothers of premature infants (17,1 %) and in 31 out of 52 mothers of full-term infants (59,6 %). In the premature infant group there were pairs with matching pathogens in 30 out of 130 cases (23,1 %, 95 % CI: 16,1-31,3), and in the full-term infant group there was a match in 4 out of 21 cases (19 %, 95 % CI: 5,4 – 41,9). The number needed to test to have a 90 % probability of success for pathogen detection varies between 9 and 11 in the most favorable case and 26 and 32 in the least favorable case, depending on the evaluation method. Conclusion: In cases of neonatal sepsis, the sepsis-causing pathogen was successfully detected through prior analysis of a maternal smear in 7 % of full-term infants and in 19 % of premature infants. The number needed to test was relatively high in all groups. The value of maternal smears for identifying neonatal sepsis-causing pathogens need to be critically questioned

Investigation of wedged pile due to the interaction of vertical load and moment

Ehitusinseneriõppe magistritöö Maaehituse õppekavalKiilvaiasid on valdavalt kasutatud Eestis. Ehitussektori konservatiivsuse tõttu mujal maailmas lühikesi kiilvaiu ei kasutada. Kiilvaiadega on varasemalt katseid tehtuid, kuid arvutusmetoodika erinevate koormusolukorade kohta puudub. Uuringuid vertikaalkoormuse ja momendi koosmõjul ei ole tehtud. Sellest probleemist tulenevalt on töö eesmärk uurida mudelkiilvaia käitumist vertikaalkoormuse ja momendi koosmõjul. Magistritöös analüüsitakse katseliselt mudelkiilvaia käitumist. Katsed viidi läbi Maaülikooli konstruktsioonide labori liivakastis. Mudelkiilvaiaga viidi läbi staatilised- ja dünaamilised koormuskatsed. Katsetes kasutati mudelkiilvaia, mis on praktikas kasutust leidnud kahe meetrise kiilvaia viiekordne vähendatud mudel. Vertikaalkoormusega koormati vaiasid viiel koormusastel, iga astmega teostati kolm katset. Momenti suurendati igal koormusastmel kuni kandevõime ammendumiseni. Katsetulemusi protokolliti, koostati graafikud ja analüüsiti. Staatilise ja dünaamilise kandevõime katse tulemusi võrreldi varasemate uurimistöö tulemustega. Momendi kandevõimet võrreldi praktikas kasutust leidnud arvutusmudeliga. Katsetulemusi analüüsides selgus, et arvutusvalem ülehindab momendi kandevõimet väikesel vertikaalkoormusel ja alahindab suurematel koormustel.Wedged piles are mostly used in Estonia, as other countries have more conservative approach to construction. There is some research about using wedge piles, but the problem is lack of calculating methodology to assess different load conditions. There is no research about interaction of vertical load and moment. Thus, the aim of this thesis is to analyze behavior of wedge pile under the interaction of vertical load and moment. Behavior of wedge pile is analyzed through experiments. The experiments were held in sand pit at laboratory in Estonian University of Life Sciences. Experiments included research of the effects of static and dynamic load to wedge pile placed in sand. All experiments were carried out with the model pile, which is five times reduced model of a commonly used 2 m long wedge pile. To assure the reliability of the results, the model piles were loaded with vertical load in five levels, each level was tested three times. The moment was increased in every load level until exhaustion of load capacity. All experiments were recorded, drawn up in graphs and analyzed. The results of static and dynamic tests were compared to results of research made earlier. The load capacity of moment was compared with calculating methodology which is most used. The analysis of the experiment revealed that present calculating methodology overestimates the load capacity at small amount of vertical load and underestimates at larger amount of vertical load

Be aware of diversity and deal with it – Learning from dilemmas

Dilemma-Diskussionen bringen im Unterricht vielerlei Diversitätsaspekte zum Vorschein. Einerseits zeigen sie die Diversität moralischer Ideale und Überzeugungen und ihre Ko-Konstruktion in unterschiedlichen Lebenswelten, andererseits trainieren sie gleichzeitig den Umgang mit Diversität. Voraussetzung dafür ist eine für die Versuchsgruppe geeignete Dilemma-Geschichte und die Einhaltung von Diskussionsregeln. (DIPF/Orig.)Dilemma discussions bring out many aspects of diversity in the classroom. On the one hand, they show the diversities of moral ideals and convictions and their co-construction in different lifeworlds; on the other hand, they simultaneously train how to deal with diversity. The prerequisite for this is a dilemma story suitable for the experimental group and adherence to discussion rules. (DIPF/Orig.

CO2 hydrogenation to methanol over partially embedded Cu within Zn-Al oxide and the effect of indium

Developing effective catalysts for CO2 hydrogenation to methanol is an important step to improve the efficiency of a promising process for green synthesis of fuels and chemicals. Optimizing the Cu dispersion is often the main goal in preparing Cu/ZnO-based catalysts due to the strong dependence of the catalytic activity on the Cu surface area. However, the catalytic properties are also related to the nature of the Cu-ZnO interface. Herein, a series of hydrotalcite-derived Cu/ZnO/Al2O3 catalysts were prepared for CO2 hydrogenation to methanol. The preparation method results in partially embedded Cu particles within the Zn-Al oxide matrix. This microstructure exhibits significantly enhanced intrinsic activity and methanol selectivity. Loss of the interfacial area between Cu and Zn-Al mixed oxide phase due to sintering of Zn-Al matrix is identified as the main reason for deactivation of the HT-derived catalysts. The influence of In on Cu/ZnO-based catalysts is also investigated. It is found that In decreases the activity but increases the methanol selectivity and stabilizes the Cu particles and the Zn-Al mixed oxide phase. The lower activity of the In-containing catalysts is linked to the inhibition of Cu active sites by CuxIny species.publishedVersio

Influence of different CaF2 contents and heat treatment temperature on apatite-mullite glass ceramics derived from waste materials

An apatite-mullite glass ceramics composition derived from clam shell (CS) and soda lime silicate (SLS) glass has been fabricated from a heat treatment process of composition [xCaF2·(45−x)SLS·15CS·20Al2O3·20P2O5], where x is 5, 10, 15 and 20 (wt. %). The result concluded that the Ca and Si elements were found in the CS and SLS glass respectively as a major weight composition, thereby promoting the use of waste materials in the manufacture of glass ceramic samples. Besides, the CaF2 addition lowers the glass transition temperature (Tg) and crystallisation temperature (Tc) of the glass composition. The density and percentage of the linear shrinkage of the samples differs with the addition of CaF2 and various heat treatment temperatures. For the structural properties’ analysis, the formation of fluorapatite with a needle-like microstructure and mullite phase was enhanced with a higher CaF2 content, while the growth of the anorthite phase was observed to occur at a higher heat treatment temperature. Generally, the addition of ahigh CaF2 content with the help of heat treatment in apatitemullite glass ceramics composition greatly promotes the crystallisation of the fluorapatite phase, which is crucial for denture glass ceramics

Stable amorphous georgeite as a precursor to a high-activity catalyst .

Copper and zinc form an important group of hydroxycarbonate minerals that include zincian malachite, aurichalcite, rosasite and the exceptionally rare and unstable—and hence little known and largely ignored1—georgeite. The first three of these minerals are widely used as catalyst precursors2, 3, 4 for the industrially important methanol-synthesis and low-temperature water–gas shift (LTS) reactions5, 6, 7, with the choice of precursor phase strongly influencing the activity of the final catalyst. The preferred phase2, 3, 8, 9, 10 is usually zincian malachite. This is prepared by a co-precipitation method that involves the transient formation of georgeite11; with few exceptions12 it uses sodium carbonate as the carbonate source, but this also introduces sodium ions—a potential catalyst poison. Here we show that supercritical antisolvent (SAS) precipitation using carbon dioxide (refs 13, 14), a process that exploits the high diffusion rates and solvation power of supercritical carbon dioxide to rapidly expand and supersaturate solutions, can be used to prepare copper/zinc hydroxycarbonate precursors with low sodium content. These include stable georgeite, which we find to be a precursor to highly active methanol-synthesis and superior LTS catalysts. Our findings highlight the value of advanced synthesis methods in accessing unusual mineral phases, and show that there is room for exploring improvements to established industrial catalysts

Cu-ZrO2 catalysts with highly dispersed Cu nanoclusters derived from ZrO2@ HKUST-1 composites for the enhanced CO2 hydrogenation to methanol

In this study, a series of Cu-ZrO2 catalysts with highly dispersed Cu nanoclusters were prepared via the calcination and reduction of ZrO2@HKUST-1 precursors. These catalysts demonstrated an outstanding selectivity in the yield of methanol during CO2 hydrogenation. The space-time yield (STY) of methanol is 5.2 times higher than that of those similar catalysts reported by other researchers, which were prepared using conventional method and tested under the same testing conditions. Density functional theory (DFT) study revealed that the activation of CO2 occurs at the Cu-ZrO2 interfaces and facilitates the hydrogenation of CO2 to methanol. It is concluded that the controlled formation of the highly dispersed Cu nanoclusters not only provides a large number of highly efficient active centers for CO2 hydrogenation, but also leads the generation of more Cu-ZrO2 interfaces. These two effects contribute to the superior catalytic performance of the nano Cu-ZrO2 catalyst in CO2 hydrogenation