Investigating movement in the laboratory: dispersal apparatus designs and the red flour beetle,Tribolium castaneum

The natural dispersal of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) has been emulated in the laboratory for more than 50 years, using a simple dispersal apparatus. This has typically comprised of a starting container (initial resource or patch) connected by tubing, which contains thread for the animals to climb into a tube and hence to an end container. That is, beetles move to a new viable resource or patch from an inter‐patch zone or non‐viable habitat. We modified this basic apparatus design to test the effect of tubing length and tubing insertion angle on the dispersal rate and proportion of successful dispersers. We expected that the proportion of successful dispersers would be repeatable within each apparatus design, and that increasing tubing length and steepness of the insertion angle would reduce dispersal rate and success across apparatus designs. Dispersal increased linearly through time, similarly so for both males and females. The design with the most vertical tubing insertion angle had a lower proportion of successful dispersers. Tubing length also had a negative relationship with dispersal success (as judged by insects reaching the end container), but a significant reduction in dispersal success was only apparent between the shortest and longest tubing between containers. We suggest that locating and climbing the vertical section of string before they can enter the tubing between containers restricts dispersal and that at higher densities, insects exhibit greater inclination to climb. This type of apparatus has flexible design tolerances and further potential to study the dispersal of other small insect species that primarily use pedestrian locomotion.     

Responses of a wetland ecosystem to the controlled introduction of invasive fish

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Temperature effects on forest understorey plants in hedgerows: a combined warming and transplant experiment

Background and AimsHedgerows have been shown to improve forest connectivity, leading to an increased probability of species tracking the shifting bioclimatic envelopes. However, it is still unknown how species in hedgerows respond to temperature changes, and whether effects differ compared with those in nearby forests. We aimed to elucidate how ongoing changes in the climate system will affect the efficiency of hedgerows in supporting forest plant persistence and migration in agricultural landscapes.MethodsHere we report results from the first warming experiment in hedgerows. We combined reciprocal transplantation of plants along an 860-km latitudinal transect with experimental warming to assess the effects of temperature on vegetative growth and reproduction of two common forest herbs (Anemone nemorosa and Geum urbanum) in hedgerows versus forests.Key ResultsBoth species grew taller and produced more biomass in forests than in hedgerows, most likely due to higher competition with ruderals and graminoids in hedgerows. Adult plant performance of both species generally benefitted from experimental warming, despite lower survival of A. nemorosa in heated plots. Transplantation affected the species differently: A. nemorosa plants grew taller, produced more biomass and showed higher survival when transplanted at their home site, indicating local adaptation, while individuals of G. urbanum showed greater height, biomass, reproductive output and survival when transplanted northwards, likely owing to the higher light availability associated with increasing photoperiod during the growing season.ConclusionsThese findings demonstrate that some forest herbs can show phenotypic plasticity to warming temperatures, potentially increasing their ability to benefit from hedgerows as ecological corridors. Our study thus provides novel insights into the impacts of climate change on understorey plant community dynamics in hedgerows, and how rising temperature can influence the efficiency of these corridors to assist forest species’ persistence and colonization within and beyond their current distribution range.     

Pulmonary function,exhaled nitric oxide and symptoms in asthma patients with obesity: a cross-sectional study

Background

Obesity is a risk factor for the development of asthma. In patients with obesity the diagnosis of asthma is often based on symptoms, but without objective measurements. Nevertheless, obesity-associated asthma is recognized as a distinct asthma phenotype. Therefore, this study explores lung function and symptoms in asthma patients with and without obesity.

Methods

The Netherlands Epidemiology of Obesity (NEO) study is a population-based cohort study with 6671 participants (aged 45–65 years) of whom 472 had asthma. Of this latter group, linear regression analysis was used to examine differences in lung function and symptoms between asthma patients with (n?=?248) and without obesity (n?=?224), and between asthma patients with and without increased Fe_NO. Analyses were adjusted for confounders.

Results

Asthma patients with obesity had lower predicted FEV₁ and FVC values than patients without obesity [adjusted mean difference (MD) -3.3% predicted, 95% CI -6.5, ?0.2; adjusted MD ?5.0% predicted, 95% CI -7.8, ?2.1]. The prevalence of symptoms was higher in patients with obesity. Asthma patients with obesity and with increased Fe_NO had lower FEV₁ and FEV₁/FVC values compared with those with low Fe_NO (adjusted MD ?6.9% predicted, 95% CI -11.7, ?2.0; ?2.4%, 95% CI -4.6, ?0.2).

Conclusion

Asthma patients with obesity had lower FEV₁ and FVC values than patients without obesity. This suggests that patients with obesity have restrictive lung function changes, rather than obstructive changes. Asthma patients with obesity and increased Fe_NO showed more obstructive changes. Fe_NO might help to identify patients with eosinophilic inflammation-driven asthma, whereas patients with low Fe_NO might have an obesity-associated asthma phenotype in which symptoms are partly caused by the obesity.

     

Low flow extracorporeal CO<Subscript>2</Subscript> removal in ARDS patients: a prospective short-term crossover pilot study

Background

Lung protective mechanical ventilation (MV) is the corner stone of therapy for ARDS. However, its use may be limited by respiratory acidosis.This study explored feasibility of, effectiveness and safety of low flow extracorporeal CO₂ removal (ECCO₂R).

Methods

This was a prospective pilot study, using the Abylcap® (Bellco) ECCO₂R, with crossover off-on-off design (2-h blocks) under stable MV settings, and follow up till end of ECCO₂R. Primary endpoint for effectiveness was a 20% reduction of PaCO₂ after the first 2-h. Adverse events (AE) were recorded prospectively.We included 10 ARDS patients on MV, with PaO₂/FiO₂?<?150 mmHg, tidal volume?≤?8 mL/kg with positive end-expiratory pressure ≥?5 cmH₂O, FiO₂ titrated to SaO₂ 88–95%, plateau pressure ≥?28 cmH₂O, and respiratory acidosis (pH <7.25).

Results

After 2-h of ECCO₂R, 6 patients had a ≥?20% decrease in PaCO₂ (60%); PaCO₂ decreased 28.4% (from 58.4 to 48.7 mmHg, p?=?0.005), and pH increased (1.59%, p?=?0.005). ECCO₂R was hemodynamically well tolerated. During the whole period of ECCO₂R, 6 patients had an AE (60%); bleeding occurred in 5 patients (50%) and circuit thrombosis in 3 patients (30%), these were judged not to be life threatening.

Conclusions

In ARDS patients, low flow ECCO₂R significantly reduced PaCO₂ after 2 h, Follow up during the entire ECCO₂R period revealed a high incidence of bleeding and circuit thrombosis.

Trial registration

https://clinicaltrials.gov identifier: NCT01911533, registered 23 July 2013.

     

ReCiPe2016: a harmonised life cycle impact assessment method at midpoint and endpoint level

Purpose

Life cycle impact assessment (LCIA) translates emissions and resource extractions into a limited number of environmental impact scores by means of so-called characterisation factors. There are two mainstream ways to derive characterisation factors, i.e. at midpoint level and at endpoint level. To further progress LCIA method development, we updated the ReCiPe2008 method to its version of 2016. This paper provides an overview of the key elements of the ReCiPe2016 method.

Methods

We implemented human health, ecosystem quality and resource scarcity as three areas of protection. Endpoint characterisation factors, directly related to the areas of protection, were derived from midpoint characterisation factors with a constant mid-to-endpoint factor per impact category. We included 17 midpoint impact categories.

Results and discussion

The update of ReCiPe provides characterisation factors that are representative for the global scale instead of the European scale, while maintaining the possibility for a number of impact categories to implement characterisation factors at a country and continental scale. We also expanded the number of environmental interventions and added impacts of water use on human health, impacts of water use and climate change on freshwater ecosystems and impacts of water use and tropospheric ozone formation on terrestrial ecosystems as novel damage pathways. Although significant effort has been put into the update of ReCiPe, there is still major improvement potential in the way impact pathways are modelled. Further improvements relate to a regionalisation of more impact categories, moving from local to global species extinction and adding more impact pathways.

Conclusions

Life cycle impact assessment is a fast evolving field of research. ReCiPe2016 provides a state-of-the-art method to convert life cycle inventories to a limited number of life cycle impact scores on midpoint and endpoint level.

     

Quality of citizen science data and its consequences for the conservation of skipper butterflies (Hesperiidae) in Flanders (northern Belgium)

Citizen science projects have become important data sources for ecologists. However, opportunistic data are not only characterized by spatial and temporal biases, but probably also contain species identification errors, especially concerning morphologically similar species. Such misidentifications may result in wrongly estimated distribution ranges and trends, and thus in inadequate conservation measures. We illustrate this issue with three skipper butterflies (Hesperiidae) in Flanders (northern Belgium) using photographs uploaded with observations in data portals. Ochlodes sylvanus and Thymelicus lineola records had relatively low identification error rates (1 and 11?%, respectively), but the majority (59?%) of Thymelicus sylvestris records turned out to be misidentified. Using verified records only allowed us to model their distribution more accurately, especially for T. sylvestris whose actual distribution area had hitherto been strongly overestimated. An additional field study on T. sylvestris confirmed the species distribution model output as the species was almost completely restricted to sites with verified records and was largely absent from sites with unverified records. The preference of T. sylvestris for unimproved grasslands was confirmed by the negative correlation between its model-predicted presence and elevated nitrogen and ammonia levels. Thus, quality control of citizen science data is of major importance to improve the knowledge of species distribution ranges, biotope preferences and other limiting factors. This, in turn, will help to better assess species conservation statuses and to suggest more appropriate management and mitigation measures.     

First record of resting cysts of the benthic dinoflagellate Prorocentrum leve in a natural reservoir in Gujan‐Mestras,Gironde, France

The resting cysts of the benthic dinoflagellate Prorocentrum leve from a natural reservoir in Gujan‐Mestras (Gironde, France) were described in this study. The incubated urn‐shaped cysts gave rise to cells of P. leve. Morphological observations through light microscopy and scanning electron microscopy, particularly of the periflagellar platelets, combined with large subunit ribosomal DNA sequences obtained through single‐cell analysis confirm their affinity to the species P. leve. The cysts were characterized by a specific shape and the presence of an anterior plug. This is the first conclusive evidence for fossilizable resting stages within the Prorocentrales, one of the major orders within the Dinophyceae. Palynological treatments show that the cysts and endospores withstand hydrochloric and hydrofluoric acids. Micro‐Fourier transform infrared analysis on single specimens suggests that the composition of the endospore is cellulosic and the cyst wall a more robust, noncellulosic β‐glucan. The spectra overall are similar to other published spectra of resting cysts from autotrophic, planktonic dinoflagellates.     

Expression of effector gene SIX1 of Fusarium oxysporum requires living plant cells

Fusarium oxysporum is an asexual, soil inhabiting fungus that comprises many different formae speciales, each pathogenic towards a different host plant. In absence of a suitable host all F. oxysporum isolates appear to have a very similar lifestyle, feeding on plant debris and colonizing the rhizosphere of living plants. Upon infection F. oxysporum switches from a saprophytic to an infectious lifestyle, which probably includes the reprogramming of gene expression. In this work we show that the expression of the known effector gene SIX1 of F. oxysporum f. sp. lycopersici is strongly upregulated during colonization of the host plant. Using GFP (green fluorescent protein) as reporter, we show that induction of SIX1 expression starts immediately upon penetration of the root cortex. Induction requires living plant cells, but is not host specific and does not depend on morphological features of roots, since plant cells in culture can also induce SIX1 expression. Taken together, F. oxysporum seems to be able to distinguish between living and dead plant material, preventing unnecessary switches from a saprophytic to an infectious lifestyle.     

New trends for metal complexes with anticancer activity

Medicinal inorganic chemistry can exploit the unique properties of metal ions for the design of new drugs. This has, for instance, led to the clinical application of chemotherapeutic agents for cancer treatment, such as cisplatin. The use of cisplatin is, however, severely limited by its toxic side-effects. This has spurred chemists to employ different strategies in the development of new metal-based anticancer agents with different mechanisms of action. Recent trends in the field are discussed in this review. These include the more selective delivery and/or activation of cisplatin-related prodrugs and the discovery of new non-covalent interactions with the classical target, DNA. The use of the metal as scaffold rather than reactive centre and the departure from the cisplatin paradigm of activity towards a more targeted, cancer cell-specific approach, a major trend, are discussed as well. All this, together with the observation that some of the new drugs are organometallic complexes, illustrates that exciting times lie ahead for those interested in 'metals in medicine'.