Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling approach should be useful in future research to expand our knowledge of how competition modulates forest communities across environmental gradients.

Analysing the effect of stand density and site conditions on structure and growth of oak species using Nelder trials along an environmental gradient:experimental design,evaluation methods,and results

Background: Most current approaches in forest science and practice require information about structure and growth of individual trees rather than- or in addition to- sum and mean values of growth and yield at forest stand level as provided by classic experimental designs. By inventing the wheel design, Nelder provided the possibility to turn to the individual tree as basic information unit. Such trials provide valuable insights into the dependency of growth on stand density at particular sites.Methods: Here, we present an extension of the original design and evaluation by Nelder.(i) We established Nelder wheels along an environmental gradient through Europe in atlantic climate in Belgium and Germany, Mediterranean climate in Italy, continental climate in Hungary as well as on high land climate in Mexico. Such disjunct Nelder wheels along an environmental gradient can be regarded and analysed as a two-factor design with the factors of site condition and stand density.(ii) We present an advanced statistical approach to evaluate density dependent growth dynamics of trees planted in form of the Nelder design, which considers spatio-temporal autocorrelation.(iii)We prove the usefulness of the methods in improving ecological theory concerning density related productivity,trade-offs between facilitation and competition, and allometric relations between size variables.Results: First evaluations based on remeasured Nelder wheels in oak(Quercus robur L.) show a size growth differentiation during the first observation period. In particular, height growth is accelerated under higher competition indicating facilitation effects. We detect furthermore a high variability in allometric relations.Conclusions: The proposed design, methods, and results are discussed regarding their impact on forest practice,model building, and ecological theory. We conclude that the extended Nelder approach is highly efficient in providing currently lacking individual tree level information.

Advances in single-cell sequencing:insights from organ transplantation

Single-cell RNA sequencing(scRNA-seq)is a comprehensive technical tool to analyze intracellular and intercellular interaction data by whole transcriptional profile analysis.Here,we describe the application in biomedical research,focusing on the immune system during organ transplantation and rejection.Unlike conventional transcriptome analysis,this method provides a full map of multiple cell populations in one specific tissue and presents a dynamic and transient unbiased method to explore the progression of allograft dysfunction,starting from the stress response to final graft failure.This promising sequencing technology remarkably improves individualized organ rejection treatment by identifying decisive cellular subgroups and cell-specific interactions.

Light Meter for Measuring Photosynthetically Active Radiation

Measurement of photosynthetically active radiation (PAR) incident on photosynthetic organisms is a crucial measurement for understanding how organisms respond to various light conditions, and for calculating electron flow through the photosynthetic machinery. Measurements of PAR are typically performed in the region of the electromagnetic spectrum between 400 - 700 nm, which is the region of radiation that is responsible for promoting photosynthesis. Typically, to ensure that the sensor measures in this range, the implementation of long- and short-pass filters is required. Although this allows the exclusion of radiation outside of the PAR region, such filters can be expensive. Additionally, the implementation of autonomous PAR measurements requires costly commercial instruments. Here, a straight-forward, inexpensive apparatus has been designed and constructed using a sensor that can distinguish between red, green, blue and white light. The constructed apparatus was able to perform comparably to a commercial PAR sensor. Furthermore, the implementation of the device to measure PAR intensity over a three-day period shows how the apparatus can be implemented for use as a constant light monitor.

Systems Biology of Plant-Microbiome Interactions

In natural environments,plants are exposed to diverse microbiota that they interact with in complex ways.While plant-pathogen interactions have been intensely studied to understand defense mechanisms in plants,many microbes and microbial communities can have substantial beneficial effects on their plant host.Such beneficial effects include improved acquisition of nutrients,accelerated growth,resilience against pathogens,and improved resistance against abiotic stress conditions such as heat,drought,and salinity.However,the beneficial effects of bacterial strains or consortia on their host are often cultivar and species specific,posing an obstacle to their general application.Remarkably,many of the signals that trigger plant immune responses are molecularly highly similar and often identical in pathogenic and beneficial microbes.Thus,it is unclear what determines the outcome of a particular microbe-host interaction and which factors enable plants to distinguish beneficials from pathogens.To unravel the complex network of genetic,microbial,and metabolic interactions,including the signaling events mediating microbe-host interactions,comprehensive quantitative systems biology approaches will be needed.

The Perception of Flood Risks: A Case Study of Babessi in Rural Cameroon

Although risk perception of natural hazards has been identified as an important determinant for sound policy design,there is limited empirical research on it in developing countries.This article narrows the empirical literature gap.It draws from Babessi,a rural town in the Northwest Region of Cameroon.Babessi was hit by a severe flash flood in 2012.The cross-disciplinary lens applied here deciphers the complexity arising from flood hazards,often embedded in contexts characterized by poverty,a state that is constrained in disaster relief,and market-based solutions being absent.Primary data were collected via snowball sampling.Multinomial logistic regression analysis suggests that individuals with leadership functions,for example,heads of households,perceive flood risk higher,probably due to their role as household providers.We found that risk perception is linked to location,which in turn is associated with religious affiliation.Christians perceive floods riskier than Muslims because the former traditionally reside at the foot of hills and the latter uphill;rendering Muslims less exposed and eventually less affected by floods.Finally,public disaster relief appears to have built up trust and subsequently reduced risk perception,even if some victims remained skeptical of state disaster relief.This indicates strong potential benefits of public transfers for flood risk management in developing countries.

Zn metabolism of monogastric species and consequences for the definition of feeding requirements and the estimation of feed Zn bioavailability

A major goal of mineral nutrition research is to provide information of feed zinc (Zn) utilization efficiency and gross Zn requirements as affected by changing rearing conditions. This can be achieved only by applying precise experimental models that acknowledge the basic principles of Zn metabolism. This review article summarizes the most important aspects of Zn homeostasis in monogastric species, including molecular aspects of Zn acquisition and excretion. Special emphasis is given to the role of the skeleton as well as the exocrine pancreas for animal Zn metabolism. Finally, we discuss consequences arising from these physiological principles for the experimental design of trials which aim to address questions of Zn requirements and bioavailability.

DNA methylation profile of a hepatosplenic gamma/delta T-cell lymphoma patient associated with response to interferon-α therapy

The 2–5%γδT cells in healthy human peripheral blood recognize nonpeptide antigens,in contrast toαβT cells.1 DistinctγδT-cell malignancies have been identified,with hepatosplenic T-cell lymphoma(γδ-HSTL)being a rare but aggressive(median survival 13 months)subset.2γδ-HSTL usually presents with hepatosplenomegaly without lymphadenopathy,anemia,and thrombocytopenia.It is histologically characterized by the involvement of the hepatic sinusoids,splenic red pulp and bone marrow interstitium,with or without leukemic presentation in peripheral blood.3 A standard treatment regimen is not well established,but therapy mostly includes various chemotherapeutic agents.Notably,interferon-α(IFN-α)has been proven to be effective in some patients withγδ-HSTL,but other patients require allogeneic or autologous stem cell transplantation.

Strategies and challenges to increase the precision in feeding zinc to monogastric livestock

Practical diets for monogastric livestock must be supplemented with zinc(Zn) due to their high contents of antagonistic substances like phytates. Current feeding recommendations include quite generous safety margins because of uncertainties regarding the gross Zn requirements under varying rearing conditions.Furthermore, the use of pharmacological Zn doses to stabilise animal performance and wellbeing is widespread. Taken together, modern diets for pigs and poultry contain considerably more Zn than necessary to meet animal requirements, which is associated with concerns related to the environment as well as animal and consumer safety. Therefore, European authorities most recently reduced the allowed upper limits for Zn in complete feed. To maintain animal productivity and wellbeing while reducing the Zn load in complete feed, all measures that stabilize feed Zn bioavailability must be applied. Most importantly, reliable information on the gross Zn requirement under practical conditions must be provided, considering the bioavailability of native or supplemented feed Zn, antagonisms with dietary factors as well as the physiological status of the animal.

Affairs happen---to whom？ A study on extrapair paternity in common nightingales

Most birds engage in extrapair copulations despite great differences across and within species. Besides cost and benefit considerations of the two sex environmental factors have been found to alter mating strategies within or between populations and/or over time. For socially monogamous species, the main advantage that females might gain from mating with multiple males is probably increasing their offspring＇s genetic fitness. Since male （genetic） quality is mostly not directly meas- urable for female birds, （extrapair） mate choice is based on male secondary traits. In passerines male song is such a sexual ornament indicating male phenotypic and/or genetic quality and song repertoires seem to affect female mate choice in a number of species. Yet their role in extrapair mating behavior is not well understood. In this study, we investigated the proportion of extrapair paternity （EPP） in a population of common nightingales Luscinia megarhynchos. We found that EPP rate was rather high （21.5% of all offspring tested） for a species without sexual dimorphism and high levels of paternal care. Furthermore, the occurrence of EPP was strongly related to the spatial distribution of male territories with males settling in densely occupied areas having higher proportions of extrapair young within their own brood. Also, song repertoire size affected EPP： here larger repertoires of social mates were negatively related to the probability of being cuck- olded. When directly comparing repertoires sizes of social and extrapair mates, extrapair mates tended to have larger repertoires. We finally discuss our results as a hint for a flexible mating strat- egy in nightingales where several factors--including ecological as well as male song features-- need to be considered when studying reproductive behavior in monogamous species with complex song.