The 2017 consensus report of the Asia Dry Eye Society (ADES) on the definition and diagnosis of dry eyes described dry eye disease as "Dry eye is a multifactorial disease characterized by unstable ...tear film causing a variety of symptoms and/or visual impairment, potentially accompanied by ocular surface damage." The report emphasized the instability of tear film and the importance of visual dysfunction in association with dry eyes, highlighting the importance of the evaluation of tear film stability. This report also discussed the concept of tear film-oriented therapy, which stemmed from the definition, and which is centered on provision of insufficient components in each tear film layer and ocular surface epithelium. The current ADES report proposes a simple classification of dry eyes based on the concept of tear film-oriented diagnosis and suggests that there are three types of dry eye: aqueous-deficient, decreased wettability, and increased evaporation. It is suggested that these three types respectively coincide with the problems of each layer: aqueous, membrane-associated mucins, and lipid/secretory mucin. Although each component cannot be quantitatively evaluated with the current technology, a practical diagnosis based on the patterns of fluorescein breakup is recommended. The Asia Dry Eye Society classification report suggests that for a practical use of the definition, diagnostic criteria and classification system should be integrated and be simple to use. The classification system proposed by ADES is a straightforward tool and simple to use, only through use of fluorescein, which is available even to non-dry eye specialists, and which is believed to contribute to an effective diagnosis and treatment of dry eyes.
Trophic interactions are often deduced from body size differences, assuming that predators prefer prey smaller than themselves because larger prey are more difficult to subdue. This has mainly been ...confirmed in aquatic ecosystems, but rarely in terrestrial ecosystems, especially in arthropods.
Our goal was to validate whether body size ratios can predict trophic interactions in a terrestrial, plant‐associated arthropod community and whether predator hunting strategy and prey taxonomy could explain additional variation.
We conducted feeding trials with arthropods from marram grass in coastal dunes to test whether two individuals, of the same or different species, would predate each other. From the trial results, we constructed one of the most complete, empirically derived food webs for terrestrial arthropods associated with a single plant species. We contrasted this empirical food web with a theoretical web based on body size ratios, activity period, microhabitat, and expert knowledge.
In our feeding trials, predator–prey interactions were indeed largely size‐based. Moreover, the theoretical and empirically based food webs converged well for both predator and prey species. However, predator hunting strategy, and especially prey taxonomy improved predictions of predation. Well‐defended taxa, such as hard‐bodied beetles, were less frequently consumed than expected based on their body size. For instance, a beetle of average size (measuring 4 mm) is 38% less vulnerable than another average arthropod with the same length.
Body size ratios predict trophic interactions among plant‐associated arthropods fairly well. However, traits such as hunting strategy and anti‐predator defences can explain why certain trophic interactions do not adhere to size‐based rules. Feeding trials can generate insights into multiple traits underlying real‐life trophic interactions among arthropods.
This study is one of the first to investigate trophic interactions in a natural aboveground arthropod community. An accurate depiction of natural food web structure and ecosystem functioning is especially vital to predict the future destabilizing effects of the rapid decline in arthropod numbers.
Abstract
The importance of non-canonical DNA structures such as G-quadruplexes (G4) and intercalating-motifs (iMs) in the fine regulation of a variety of cellular processes has been recently ...demonstrated. As the crucial roles of these structures are being unravelled, it is becoming more and more important to develop tools that allow targeting these structures with the highest possible specificity. While targeting methodologies have been reported for G4s, this is not the case for iMs, as evidenced by the limited number of specific ligands able to bind the latter and the total absence of selective alkylating agents for their covalent targeting. Furthermore, strategies for the sequence-specific covalent targeting of G4s and iMs have not been reported thus far. Herein, we describe a simple methodology to achieve sequence-specific covalent targeting of G4 and iM DNA structures based on the combination of (i) a peptide nucleic acid (PNA) recognizing a specific sequence of interest, (ii) a pro-reactive moiety enabling a controlled alkylation reaction, and (iii) a G4 or iM ligand orienting the alkylating warhead to the reactive residues. This multi-component system allows for the targeting of specific G4 or iM sequences of interest in the presence of competing DNA sequences and under biologically relevant conditions.
Nematodes are involved in many important ecosystem functions such as nutrient cycling and plant growth. Nematode communities are thought to be structured at regional scales mainly by abiotic soil ...characteristics and climatic drivers and at local scales by habitat heterogeneity and biotic interactions. Blond dunes are dominated by marram grass (Calamagrostis arenaria), the key dune-forming plant species in Western Europe. Consequently, nematode food webs are mainly associated with marram grass in these coastal areas.
We investigated the relative importance of regional biogeographic factors and local biotic drivers, such as the vegetation's spatial structure and the occurrence of an invasive plant species, in determining the functional diversity of belowground nematode communities inhabiting the roots of marram grass and surrounding soil in coastal dune areas.
We found that nematode functional group abundances mainly differed among biogeographic regions, but that abundances could not be linked to plant-associated parameters, such as plant vitality or abundance. Additionally, the abundances of different functional groups seemed to be positively associated within both rhizosphere and bulk soil, an effect that could be the result of ecological filtering or facilitative interactions.
Nematode pressure has been assumed to be an important driver of marram grass degeneration under ceasing sand dynamics. We here show that variation in nematode functional group composition is only weakly related to these local changes in plant vigour, but that large-scale patterns in nematode communities may explain regional variation in marram dynamics in coastal dunes.
•Nematode functional groups react differently to local biotic drivers.•Roots and soil of marram grass host different, yet associated, nematode communities.•Strong positive correlations were found among soil and root functional groups.•Nematode composition showed thus regional top-down and local bottom-up structuring.
In this study, six commercial meat starters, each consisting of a pure strain of a lactic acid-fermenting bacterium (including
,
,
, and
), were tested for their ability to ferment a paste produced ...from the yellow mealworm (
). During fermentation, microbial counts, pH, and the bacterial community composition were determined. In addition, UPLC-MS was applied to monitor the consumption of glucose and the production of glutamic (Glu) and aspartic (Asp) acid. All tested starters were able to ferment the mealworm paste, judged by a pH reduction from 6.68 to 4.60-4.95 within 72 h. Illumina amplicon sequencing showed that all starters were able to colonize the substrate eciently. Moreover, the introduction of the starter cultures led to the disappearance of
and
species, which were the dominant microorganisms in un-inoculated samples. Of the six cultures tested,
was most promising as its application resulted in the largest increase (±25 mg/100 g of paste) in the content of free glutamic and aspartic acid. These amino acids are responsible for the appreciated umami flavour in fermented food products and might stimulate the acceptance of insects and their consumption.
Disturbance is thought to enhance the probability of invasive species establishment, a prerequisite for naturalisation. Coastal dunes are characterised by disturbance in the form of sand dynamics. We ...studied the effect of this disturbance on the establishment and spread of an invasive plant species (
Senecio inaequidens
) in European coastal dunes. Local sand dynamics dictate the spatial configuration of marram grass (
Calamagrostis arenaria
). Therefore, marram grass configuration was used as a reliable proxy for disturbance. Since marram grass plays a crucial role in natural dune formation, we evaluated the possible effects
S. inaequidens
could have on this process, if it is able to naturalise in European coastal dunes.
We expected the highest probability of
S. inaequidens
establishment at intermediate marram grass cover because too low cover would increase sand burial, whereas high cover would increase competition. However, our results indicate that
S. inaequidens
is quite capable of handling higher levels of sand burial. Thus, the probability of
S. inaequidens
establishment was high under low marram cover but slightly lowered when marram cover was high, hinting at the importance of competition.
We expected a negative impact of
Senecio
-altered soils on marram grass growth mediated by soil biota. However, marram grass grew better in sand gathered underneath
Senecio
plants due to abiotic soil modifications. This enhanced growth may be caused by
Senecio
leaf litter elevating nutrient concentrations in an otherwise nutrient-poor substrate. If such increased plant growth is a general phenomenon, further expansion of
S. inaequidens
could accelerate natural succession in European coastal dunes.
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