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Semi-natural habitats (SNHs) are becoming increasingly scarce in modern agricultural landscapes. This may reduce natural ecosystem services such as pest control with its putatively positive effect on crop production. In agreement with other studies, we recently reported wheat yield reductions at field borders which were linked to the type of SNH and the distance to the border. In this experimental landscape-wide study, we asked whether these yield losses have a biotic origin while analyzing fungal seed and fungal leaf pathogens, herbivory of cereal leaf beetles, and weed cover as hypothesized mediators between SNHs and yield. We established experimental winter wheat plots of a single variety within conventionally managed wheat fields at fixed distances either to a hedgerow or to an in-field kettle hole. For each plot, we recorded the fungal infection rate on seeds, fungal infection and herbivory rates on leaves, and weed cover. Using several generalized linear mixed-effects models as well as a structural equation model, we tested the effects of SNHs at a field scale (SNH type and distance to SNH) and at a landscape scale (percentage and diversity of SNHs within a 1000-m radius). In the dry year of 2016, we detected one putative biotic culprit: Weed cover was negatively associated with yield values at a 1-m and 5-m distance from the field border with a SNH. None of the fungal and insect pests, however, significantly affected yield, neither solely nor depending on type of or distance to a SNH. However, the pest groups themselves responded differently to SNH at the field scale and at the landscape scale. Our findings highlight that crop losses at field borders may be caused by biotic culprits; however, their negative impact seems weak and is putatively reduced by conventional farming practices.
Background
Subjective Social Status is used as an important predictor for psychological and physiological findings, most commonly measured with the MacArthur Scale (Ladder Test). Previous studies have shown that this test fits better in Western cultures. The idea of a social ladder itself and ranking oneself “higher” or “lower” is a concept that accords to the Western thinking.
Objectives
We hypothesize that in a culture where only the elites have adapted to a Western lifestyle, the test results reflect a higher level of accuracy for this stratum. We also expect that self-perception differs per sex.
Sample and Methods
We implemented the Ladder Test in a study of Indonesian schoolchildren aged between 5 and 13 years (boys N = 369, girls N= 364) from non-private and private schools in Kupang in 2020.
Results
Our analysis showed that the Ladder Test results were according to the Western expectations only for the private school, as the Ladder Scores significantly decreased with age (LM: p = 0.04). The Ladder Test results are best explained by “Education Father” for the non-private school pupils (p = 0.01) and all boys (p = 0.04), by “School Grades” for the private school cohort (p = 0.06) and by “Household Score” for girls (p =0.09).
Conclusion
This finding indicates that the concept of ranking oneself “high” or “low” on a social ladder is strongly implicated with Western ideas. A ladder implies social movement by “climbing” up or down. According to that, reflection of self-perception is influenced by culture.
Human sulfite oxidase (hSO) is a homodimeric two-domain enzyme central in the biological sulfur cycle. A pyranopterin molybdenum cofactor (Moco) is the catalytic site and a heme b(5) group located in the N-terminal domain. The two domains are connected by a flexible linker region. Electrons produced at the Moco in sulfite oxidation, are relayed via heme b(5) to electron acceptors or an electrode surface. Inter-domain conformational changes between an open and a closed enzyme conformation, allowing "gated" electron transfer has been suggested. We first recorded cyclic voltammetry (CV) of hSO on single-crystal Au(111)-electrode surfaces modified by self-assembled monolayers (SAMs) both of a short rigid thiol, cysteamine and of a longer structurally flexible thiol, omega-amino-octanethiol (AOT). hSO on cysteamine SAMs displays a well-defined pair of voltammetric peaks around -0.207 V vs. SCE in the absence of sulfite substrate, but no electrocatalysis. hSO on AOT SAMs displays well-defined electrocatalysis, but only "fair" quality voltammetry in the absence of sulfite. We recorded next in situ scanning tunnelling spectroscopy (STS) of hSO on AOT modified Au(111)-electrodes, disclosing, a 2-5 % surface coverage of strong molecular scale contrasts, assigned to single hSO molecules, notably with no contrast difference in the absence and presence of sulfite. In situ STS corroborated this observation with a sigmoidal tunnelling current/overpotential correlation.
Background: Members of the same social group tent to have the same body height. Migrants tend to adjust in height to their host communities.
Objectives: Social-Economic-Political-Emotional (SEPE) factors influence growth. We hypothesized that Vietnamese young adult migrants in Germany (1) are taller than their parents, (2) are as tall as their German peers, and (3) are as tall as predicted by height expectation at age 13 years.
Sample: The study was conducted in 30 male and 54 female Vietnamese migrants (mean age 26.23 years. SD=4.96) in Germany in 2020.
Methods: Information on age, sex, body height, school and education, job, height and ethnicity of best friend, migration history and cultural identification, parental height and education, and recalled information on their personal height expectations at age 13 years were obtained by questionnaire. The data were analyzed by St. Nicolas House Analysis (SNHA) and multiple regression.
Results: Vietnamese young adults are taller than their parents (females 3.85cm, males 7.44cm), but do not fully attain height of their German peers. The body height is positively associated with the height of best friend (p < 0.001), the height expectation at age 13 year (p < 0.001), and father’s height (p=0.001).
Conclusion: Body height of Vietnamese migrants in Germany reflects competitive growth and strategic growth adjustments. The magnitude of this intergenerational trend supports the concept that human growth depends on SEPE factors.
Waldökosysteme unterliegen vielfältigen Einflüssen wie forstlicher Bewirtschaftung, Stickstoffdeposition, Veränderung des Grundwasserspiegels oder der Einwanderung invasiver Arten. Die Wiederholung historischer Vegetationsaufnahmen ist ein wichtiges Mittel, um Veränderungen der Pflanzengesellschaften zu dokumentieren und mögliche Hauptursachen (Treiber) zu bestimmen. Wir haben 2015 den Vegetationswandel auf 140 semi-permanenten Plots in Wirtschaftswäldern der Elbtalniederung im Nordostdeutschen Tiefland (Sachsen-Anhalt, Brandenburg) untersucht. Die Erstaufnahme erfolgte von 1956 bis 1963. Die Vegetationsaufnahmen decken ein fast einzigartig breites Spektrum unterschiedlicher Waldstandorte ab, das von Feuchtwäldern (Au-, Bruch- und Moorwäldern des Alnion incanae, Alnion glutinosae und Betulion pubescentis) über bodensaure Eichen-Mischwälder (Quercion roboris) bis hin zu bodensauren, meist trockenen Kiefernwäldern mit unterschiedlicher Nährstoffausstattung (Dicrano-Pinion) reicht.
Die Veränderungen der Vegetation haben wir mit Hilfe von Bestandesdaten, Gewinner- und Verliererarten, der α- und β -Diversität sowie der Ellenberg-Zeigerwerte für Stickstoff, Reaktion, Feuchte und Licht analysiert. Dabei wurden, anders als in den meisten bisherigen Wiederholungsuntersuchungen, auch Flächen berücksichtigt, auf denen bis zur Zweitaufnahme ein vollständiger Bestandeswechsel stattgefunden hatte.
Insbesondere in den Feuchtwäldern und den bodensauren Wäldern mit mäßig guter Nährstoffversorgung sind Wechsel der Hauptbaumarten zu verzeichnen; außerdem wurden viele Kiefernbestände zwischenzeitlich neu begründet. Die Artenzahl hat insgesamt und in fast allen Waldtypen abgenommen, die β-Diversität ist jedoch unverändert geblieben bzw. hat sich erhöht. Die Zeigerwerte deuten auf eine Abnahme der Bodenfeuchte in den Au-, Bruch-, und Moorwäldern hin, während insbesondere die bodensauren Kiefernwälder dunkler, nährstoffreicher und feuchter geworden sind. Die Anzahl der Verlierer-Arten ist mehr als doppelt so hoch wie die der Gewinner-Arten, jedoch mit unterschiedlicher Entwicklung in den einzelnen Waldtypen. Insbesondere die nassen und feuchten Wälder, die bodensauren Eichen-Mischwälder und die Flechten-Kiefernwälder haben die meisten ihrer charakteristischen Arten verloren.
Veränderungen der Vegetation in den Feuchtwäldern gehen v. a. auf lokal gesunkene Grundwasserspiegel und eine dadurch gestiegene Nährstoffverfügbarkeit zurück; die Artenzusammensetzung der Auwälder wurde zudem sehr stark durch forstliche Eingriffe beeinflusst. Ursachen für den Trend zu feuchteren und nährstoffreicheren Bedingungen in ehemals trockenen bodensauren Kiefern- und Eichenwäldern sind Stickstoffeinträge sowie eine Sukzession nach Aufgabe historischer Waldnutzungs-formen (Streunutzung, Waldweide). Obwohl sich die einzelnen Waldtypen unterschiedlich entwickelt haben, sind Eutrophierung, sinkende Grundwasserspiegel und Waldbaumaßnahmen insgesamt die wichtigsten Ursachen für die beobachteten Vegetationsveränderungen. Forstliche Eingriffe wie Kahlschlag und Bestandesumbau mit Baumartenwechsel sind zugleich die Hauptursache dafür, dass es trotz Nivellierung des Standortsgradienten, gemessen an der β-Diversität, nicht zu einer Homogenisierung der Vegetation gekommen ist.
Ecological niche models (ENMs) are often used to investigate how climatic variables from known occurrence records can estimate potential species range distribution. Although climate-based ENMs provide critical baseline information, the inclusion of non-climatic predictors related to vegetation cover might generate more realistic scenarios. This assumption is particularly relevant for species with life-history traits related to forest habitats and sensitive to habitat loss and fragmentation. Here, we developed ENMs for 36 Atlantic Forest endemic birds considering two sets of predictor variables: (i) climatic variables only and (ii) climatic variables combined with the percentage of remaining native vegetation. We hypothesized that the inclusion of native vegetation data would decrease the potential range distribution of forest-dependent species by limiting their occurrence in regions harboring small areas of native vegetation habitats, despite otherwise favorable climatic conditions. We also expected that habitat restriction in the climate-vegetation models would be more pronounced for highly forest-dependent birds. The inclusion of vegetation data in the modeling procedures restricted the final distribution ranges of 22 out of 36 modeled species, while the 14 remaining presented an expansion of their ranges. We observed that species with high and medium forest dependency showed higher restriction in range size predictions between predictor sets than species with low forest dependency, which showed no alteration or range expansion. Overall, our results suggest that ENMs based on climatic and landscape variables may be a useful tool for conservationists to better understand the dynamic of bird species distributions in threatened and highly fragmented regions such as the Atlantic Forest hotspot.(c) 2021 Associacao Brasileira de Cie circumflex accent ncia Ecol ogica e Conservacao. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/ ).
Plastic pollution is an increasing environmental problem, but a comprehensive understanding of its effect in the environment is still missing. The wide variety of size, shape, and polymer composition of plastics impedes an adequate risk assessment. We investigated the effect of differently sized polystyrene beads (1-, 3-, 6-µm; PS) and polyamide fragments (5–25 µm, PA) and non-plastics items such as silica beads (3-µm, SiO2) on the population growth, reproduction (egg ratio), and survival of two common aquatic micro invertebrates: the rotifer species Brachionus calyciflorus and Brachionus fernandoi. The MPs were combined with food quantity, limiting and saturating food concentration, and with food of different quality. We found variable fitness responses with a significant effect of 3-µm PS on the population growth rate in both rotifer species with respect to food quantity. An interaction between the food quality and the MPs treatments was found in the reproduction of B. calyciflorus. PA and SiO2 beads had no effect on fitness response. This study provides further evidence of the indirect effect of MPs in planktonic rotifers and the importance of testing different environmental conditions that could influence the effect of MPs.
In this report we describe Cy5-dUTP labelling of recombinase-polymerase-amplification (RPA) products directly during the amplification process for the first time. Nucleic acid amplification techniques, especially polymerase-chain-reaction as well as various isothermal amplification methods such as RPA, becomes a promising tool in the detection of pathogens and target specific genes. Actually, RPA even provides more advantages. This isothermal method got popular in point of care diagnostics because of its speed and sensitivity but requires pre-labelled primer or probes for a following detection of the amplicons. To overcome this disadvantages, we performed an labelling of RPA-amplicons with Cy5-dUTP without the need of pre-labelled primers. The amplification results of various multiple antibiotic resistance genes indicating great potential as a flexible and promising tool with high specific and sensitive detection capabilities of the target genes. After the determination of an appropriate rate of 1% Cy5-dUTP and 99% unlabelled dTTP we were able to detect the bla(CTX-M15) gene in less than 1.6E-03 ng genomic DNA corresponding to approximately 200 cfu of Escherichia coli cells in only 40 min amplification time.
TusA is a versatile protein that links translation efficiency to cell division in Escherichia coli
(2021)
To enable accurate and efficient translation, sulfur modifications are introduced posttranscriptionally into nucleosides in tRNAs. The biosynthesis of tRNA sulfur modifications involves unique sulfur trafficking systems for the incorporation of sulfur atoms in different nucleosides of tRNA. One of the proteins that is involved in inserting the sulfur for 5-methylaminomethyl-2-thiouridine (mnm(5)s(2)U34) modifications in tRNAs is the TusA protein. TusA, however, is a versatile protein that is also involved in numerous other cellular pathways. Despite its role as a sulfur transfer protein for the 2-thiouridine formation in tRNA, a fundamental role of TusA in the general physiology of Escherichia coli has also been discovered. Poor viability, a defect in cell division, and a filamentous cell morphology have been described previously for tusA-deficient cells. In this report, we aimed to dissect the role of TusA for cell viability. We were able to show that the lack of the thiolation status of wobble uridine (U-34) nucleotides present on Lys, Gln, or Glu in tRNAs has a major consequence on the translation efficiency of proteins; among the affected targets are the proteins RpoS and Fis. Both proteins are major regulatory factors, and the deregulation of their abundance consequently has a major effect on the cellular regulatory network, with one consequence being a defect in cell division by regulating the FtsZ ring formation. <br /> IMPORTANCE More than 100 different modifications are found in RNAs. One of these modifications is the mnm(5)s(2)U modification at the wobble position 34 of tRNAs for Lys, Gln, and Glu. The functional significance of U34 modifications is substantial since it restricts the conformational flexibility of the anticodon, thus providing translational fidelity. We show that in an Escherichia coli TusA mutant strain, involved in sulfur transfer for the mnm(5)s(2)U34 thio modifications, the translation efficiency of RpoS and Fis, two major cellular regulatory proteins, is altered. Therefore, in addition to the transcriptional regulation and the factors that influence protein stability, tRNA modifications that ensure the translational efficiency provide an additional crucial regulatory factor for protein synthesis.
Background
Secondary endosymbionts of aphids provide benefits to their hosts, but also impose costs such as reduced lifespan and reproductive output. The aphid Aphis fabae is host to different strains of the secondary endosymbiont Hamiltonella defensa, which encode different putative toxins. These strains have very different phenotypes: They reach different densities in the host, and the costs and benefits (protection against parasitoid wasps) they confer to the host vary strongly.
Results
We used RNA-Seq to generate hypotheses on why four of these strains inflict such different costs to A. fabae. We found different H. defensa strains to cause strain-specific changes in aphid gene expression, but little effect of H. defensa on gene expression of the primary endosymbiont, Buchnera aphidicola. The highly costly and over-replicating H. defensa strain H85 was associated with strongly reduced aphid expression of hemocytin, a marker of hemocytes in Drosophila. The closely related strain H15 was associated with downregulation of ubiquitin-related modifier 1, which is related to nutrient-sensing and oxidative stress in other organisms. Strain H402 was associated with strong differential regulation of a set of hypothetical proteins, the majority of which were only differentially regulated in presence of H402.
Conclusions
Overall, our results suggest that costs of different strains of H. defensa are likely caused by different mechanisms, and that these costs are imposed by interacting with the host rather than the host's obligatory endosymbiont B. aphidicola.