International students' loneliness, depression and stress levels in COVID-19 crisis. The role of social media and the host university

The move to university life is characterized by strong emotions, some of them negative, such as loneliness, anxiety, and depression. These negative emotions are strengthened due to the obligatory lockdown due to the COVID-19 pandemic. Previous research indicates association among the use of social media, university satisfaction, and the aforementioned emotions. We report findings from 248 international undergraduates in The Netherlands, all students at the International School of Business. Our results indicate strong correlations between anxiety, loneliness, and COVID-19-related stress with university satisfaction together with social capital. Keywords: COVID-19; Pandemic; lockdown; loneliness; depression; anxiety; international studentsComment: 14 page

Tumour-specific microRNA expression pattern in canine intestinal T-cell-lymphomas

Intestinal T-cell lymphomas are common in dogs, but histopathological diagnosis remains challenging because of accompanying enteritis with lymphocyte involvement. Invasively taken full-layer biopsies are still required for reliable differentiation. The detection of specific microRNA expression patterns in canine intestinal T-cell lymphoma could provide new possibilities to differ intestinal lymphoma from benign inflammation and could lead to further understanding of lymphomagenesis. The objective of this study was to characterize microRNA expression in distinct groups of formalin-fixed and paraffin-embedded samples from canine intestinal T-cell lymphomas, lymphoplasmacellular enteritis and healthy intestinal tissue. In a preliminary test with two samples per group, total RNA was extracted (RNEasy FFPE Kit, Qiagen), reverse transcribed (miScript II RT Kit, Qiagen) and pre-amplified (miScript PreAmp PCR Kit, Qiagen). We performed comparative quantitative PCR on microRNA PCR Array plates (Qiagen) with pre-fabricated reactions for 183 different mature canine microRNAs. Subsequently, 12 microRNAs with conspicuous expression changes in the lymphoma group were selected and microRNA expression of all samples (n = 8) per group was analysed with individual microRNA assays (miScript Primer Assays, Qiagen) on the reverse transcribed RNA without pre-amplification. Our results revealed lymphoma-specific expression patterns, with down-regulation of the tumour-suppressing microRNAs miR-194, miR-192, miR-141 and miR-203, and up-regulation of oncogenic microRNAs, including microRNAs from the miR-106a~363 cluster. In addition, we detected only slight expression alterations between healthy intestinal tissue and lymphoplasmacellular enteritis cases. We conclude that microRNA expression patterns can be used to separate T-cell lymphomas from healthy tissue and benign inflammatory disorders

Molekulare Mechanismen der Aldosteron-Wirkung und Interaktionen des Mineralocorticoid-Rezeptors in Nierenzellen

Im Rahmen dieser Arbeit sollten Interaktionen des Mineralocorticoid-Rezeptors (MR) sowie Regulationsmechanismen des MR durch Aldosteron in Nierenzellen untersucht werden. In früheren Versuchen am Institut für Klinische Pharmakologie Mannheim wurde die schnelle (2h) Aldosteron-induzierte Genexpression in Zellen des distalen Tubulusepithels (DTEC) untersucht. Unter den in einem Mikroarray differentiell regulierten Genen wurden mehrere Proteine ausgewählt, deren Einfluss auf MR-Signalwege näher untersucht werden sollte. Es stellte sich heraus, dass die Eigenschaften unterschiedlicher Isolate der primären DTEC so stark variierten, dass keine signifikanten Resultate erreicht werden konnten. Auf die weitere Verwendung dieser Zellen wurde deshalb verzichtet. Untersuchungen an Steroidrezeptoren haben gezeigt, dass Kofaktoren eine wichtige Rolle für die Wirkung von Steroiden spielen. Auch für die Wirkung von Steroiden am MR haben solche Protein-Protein-Interaktionen sehr wahrscheinlich eine entscheidende Bedeutung. Während die Rekrutierung von Kofaktoren für die meisten Steroidrezeptoren gut untersucht ist, ist für den MR hierüber noch wenig bekannt. Mögliche Interaktionspartner des MR sollten daher mittels Affinitätschromatographie und anschließender massenspektrometrischer Analyse identifiziert werden. Hierfür wurden parallel verschiedene Systeme untersucht. Die höchsten Ausbeuten an Zielprotein, bei einem niedrigen Hintergrund an unspezifisch gebundenen Proteinen, lieferte ein System mit einer Streptavidin-Affinitätssequenz. Dieses wurde für alle Versuche im Großmaßstab eingesetzt. Es wurden zahlreiche Proteine identifiziert, die sich mit dem zytosolischen MR in einem Komplex befinden, darunter alle in der Literatur bereits beschriebenen. Die Komplexbestandteile können in folgende Gruppen eingeteilt werden: 1.Hitzeschockproteine/Chaperone 2.Proteine des intrazellulären Transportapparates 3.Metabolische Enzyme 4.Elongationsfaktoren 5.Sonstige Die relativ große Anzahl an isolierten Proteinen weist auf die Bildung von MR-Multiproteinkomplexen hin, wie dies bereits für den Glucocorticoid-Rezeptor gezeigt wurde. Zu den identifizierten Proteinen gehören bereits gut dokumentierte Interaktionen des MR (Hitzeschockproteine HSP70 und HSP90, Aktin, Tubulin), als auch bislang noch nicht für den MR, jedoch für andere Steroidrezeptoren beschriebene Interaktionspartner (p23, 14-3-3, GRP78, Elongationsfaktoren eEF1 und eEF2). Daneben wurden zahlreiche neue Proteine im MR-Komplex identifiziert. Um die differentiellen Wirkungen unterschiedlicher MR-Liganden zu verstehen, wurde die Liganden-abhängige Rekrutierung von Kofaktoren untersucht. In Gegenwart des Agonisten Aldosteron waren HSPs zu verschiedenen Zeitpunkten erwartungsgemäß in deutlich geringerer Menge an den zytosolischen MR gebunden als im unstimulierten Zustand. Außerdem wurden zwei Proteine identifiziert, die abhängig vom gebundenen Liganden im MR-Komplex gefunden wurden. GRP78 und -Propionyl-CoA-carboxylase Vorläufermolekül wurden beim unstimulierten MR wie auch nach einer Stimulation mit Aldosteron isoliert, jedoch nicht mehr nach einer Inkubation mit Spironolacton. Diese Befunde könnten auf eine bisher unerkannte Komplexität der Wirkung von MR Antagonisten hindeuten

International students' loneliness, depression and stress levels in COVID-19 crisis: The role of social media and the host university

Purpose: The move to university life is characterized by strong emotions, some of them negative, such as loneliness, anxiety, and depression. These negative emotions are strengthened due to the obligatory lockdown due to the COVID-19 pandemic. The objective of this research is to analyze the loneliness, depression and stress levels among international students, based on the use of social media and the role of the host university. Methods: The research was focused on survey data from international students In a total of 248 valid responses, we collected 171 from female students and 71 from males. 105 students are freshmen, 94 in their second year of study, 27 at the third, 20 at the fourth and 2 students graduated last summer. The dominant nationality is the Dutch (n=62) and Vietnamese (n=37). Results: Previous research indicates association among the use of social media, university satisfaction, and aforementioned emotions. The results indicate strong correlations between anxiety, loneliness, and COVID-19-related stress with university satisfaction, together with social capital. Implications: The present study will lead to practical implications, such as the formation of Universities Pandemic Crisis teams all over the world with common manuals and good practices, exchanging experience from research like the present

Origin of multiple periodicities in the Fourier power spectra of the Plasmodium falciparum genome

<p>Abstract</p> <p>Background</p> <p>Fourier transforms and their associated power spectra are used for detecting periodicities and protein-coding genes and is generally regarded as a well established technique. Many of the periodicities which have been found with this method are quite well understood such as the periodicity of 3 nt which is associated to codon usage. But what is the origin of the peculiar frequency multiples <it>k</it>/21 which were reported for a tiny section of chromosome 2 in <it>P. falciparum</it>? Are these present in other chromosomes and perhaps in related organisms? And how should we interpret fractional periodicities in genomes?</p> <p>Results</p> <p>We applied the binary indicator power spectrum to all chromosomes of <it>P. falciparum</it>, and found that the frequency overtones <it>k</it>/21 are present only in non-coding sections. We did not find such frequency overtones in any other related genomes. Furthermore, the frequency overtones were identified as artifacts of the way the genome is encoded into a numerical sequence, that is, they are frequency aliases. By choosing a different way to encode the sequence the overtones do not appear. In view of these results, we revisited early applications of this technique to proteins where frequency overtones were reported.</p> <p>Conclusions</p> <p>Some authors hinted recently at the possibility of mapping artifacts and frequency aliases in power spectra. However, in the case of <it>P. falciparum</it> the frequency aliases are particularly strong and can mask the 1/3 frequency which is used for gene detecting. This shows that albeit being a well known technique, with a long history of application in proteins, few researchers seem to be aware of the problems represented by frequency aliases.</p

Can motto-goals outperform learning and performance goals? Influence of goal setting on performance and affect in a complex problem solving task

In this paper, we bring together research on complex problem solving with that on motivational psychology about goal setting. Complex problems require motivational effort because of their inherent difficulties. Goal Setting Theory has shown with simple tasks that high, specific performance goals lead to better performance outcome than do-your-best goals. However, in complex tasks, learning goals have proven more effective than performance goals. Based on the Zurich Resource Model, so-called motto-goals should activate a person’s resources through positive affect. It was found that motto-goals are effective with unpleasant duties. Therefore, we tested the hypothesis that motto-goals outperform learning and performance goals in the case of complex problems. A total of N = 123 subject participated in the experiment. In dependence of their goal condition, subjects developed a personal motto, learning, or performance goal. This goal was adapted for the computer-simulated complex scenario Tailorshop, where subjects worked as managers in a small fictional company. Other than expected, there was no main effect of goal condition for the management performance. An unexpected gender effect revealed better performance for men than women, pointing to a potential stereotype threat. As hypothesized, motto goals led to higher positive and lower negative affect than the other two goal types. Even though positive affect decreased and negative affect increased in all three groups during Tailorshop completion, participants with motto goals reported the lowest rates of negative affect. Exploratory analyses investigated the role of affect in complex problem solving via mediational analyses and the influence of goal type on perceived goal attainment

in situ experiment

The increasing amount of plastic littered into the sea may provide a new substratum for benthic organisms. These marine fouling communities on plastic have not received much scientific attention. We present, to our knowledge, the first comprehensive analysis of their macroscopic community composition, their primary production and the polymer degradation comparing conventional polyethylene (PE) and a biodegradable starch-based plastic blend in coastal benthic and pelagic habitats in the Mediterranean Sea. The biomass of the fouling layer increased significantly over time and all samples became heavy enough to sink to the seafloor. The fouling communities, consisting of 21 families, were distinct between habitats, but not between polymer types. Positive primary production was measured in the pelagic, but not in the benthic habitat, suggesting that large accumulations of floating plastic could pose a source of oxygen for local ecosystems, as well as a carbon sink. Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies

Laboratory Test Methods to Determine the Degradation of Plastics in Marine Environmental Conditions

In this technology report, three test methods were developed to characterize the degradation of plastic in marine environment. The aim was to outline a test methodology to measure the physical and biological degradation in different habitats where plastic waste can deposit when littered in the sea. Previously, research has focused mainly on the conditions encountered by plastic items when floating in the sea water (pelagic domain). However, this is just one of the possible habitats that plastic waste can be exposed to. Waves and tides tend to wash up plastic waste on the shoreline, which is also a relevant habitat to be studied. Therefore, the degradation of plastic items buried under sand kept wet with sea water has been followed by verifying the disintegration (visual disappearing) as a simulation of the tidal zone. Most biodegradable plastics have higher densities than water and also as a consequence of fouling, they tend to sink and lay on the sea floor. Therefore, the fate of plastic items lying on the sediment has been followed by monitoring the oxygen consumption (biodegradation). Also the effect of a prolonged exposure to the sea water, to simulate the pelagic domain, has been tested by measuring the decay of mechanical properties. The test material (Mater-Bi) was shown to degrade (total disintegration achieved in less than 9 months) when buried in wet sand (simulation test of the tidal zone), to lose mechanical properties but still maintain integrity (tensile strength at break = −66% in 2 years) when exposed to sea water in an aquarium (simulation of pelagic domain), and substantially biodegrade (69% in 236 days; biodegradation relative to paper: 88%) when located at the sediment/sea water interface (simulation of benthic domain). This study is not conclusive as the methodological approach must be completed by also determining degradation occurring in the supralittoral zone, on the deep sea floor, and in the anoxic sediment

The response of seagrass (Posidonia oceanica) meadow metabolism to CO2-levels and hydrodynamic exchange determined with aquatic eddy covariance

We investigated light, water velocity, and CO2 as drivers of primary production in Mediterranean seagrass (Posidonia oceanica) meadows and neighboring bare sands using the aquatic eddy covariance technique. Study locations included an open-water meadow and a nearshore meadow, the nearshore meadow being exposed to greater hydrodynamic exchange. A third meadow was located at a CO2 vent. We found that, despite the oligotrophic environment, the meadows had a remarkably high metabolic activity, up to 20 times higher than the surrounding sands. They were strongly autotrophic, with net production half of gross primary production. Thus, P. oceanica meadows are oases of productivity in an unproductive environment. Secondly, we found that turbulent oxygen fluxes above the meadow can be significantly higher in the afternoon than in the morning at the same light levels. This hysteresis can be explained by the replenishment of nighttime-depleted oxygen within the meadow during the morning. Oxygen depletion and replenishment within the meadow do not contribute to turbulent O2 flux. The hysteresis disappeared when fluxes were corrected for the O2 storage within the meadow and, consequently, accurate metabolic rate measurements require measurements of meadow oxygen content. We further argue that oxygen-depleted waters in the meadow provide a source of CO2 and inorganic nutrients for fixation, especially in the morning. Contrary to expectation, meadow metabolic activity at the CO2 vent was lower than at the other sites, with negligible net primary production

High Net Primary Production of Mediterranean seagrass (Posidonia oceanica) Meadows Determined with Aquatic Eddy Covariance

We report primary production and respiration of Posidonia oceanica meadows determined with the non-invasive aquatic eddy covariance technique. Oxygen fluxes were measured in late spring at an open-water meadow (300 m from shore), at a nearshore meadow (60 m from shore), and at an adjacent sand bed. Despite the oligotrophic environment, the meadows were highly productive and highly autotrophic. Net ecosystem production (54 to 119 mmol m-2 d-1) was about one-half of gross primary production. In adjacent sands, net primary production was a tenth- to a twentieth smaller (4.6 mmol m-2 d-1). Thus, P. oceanica meadows are an oasis of productivity in unproductive surroundings. During the night, dissolved oxygen was depleted in the open-water meadow. This caused a hysteresis where oxygen production in the late afternoon was greater than in the morning at the same irradiance. Therefore, for accurate measurements of diel primary production and respiration in this system, oxygen must be measured within the canopy. Generally, these measurements demonstrate that P. oceanica meadows fix substantially more carbon than they respire. This supports the high rate of organic carbon accumulation and export for which the ecosystem is known