Nature 4.0: A networked sensor system for integrated biodiversity monitoring.

Ecosystem functions and services are severely threatened by unprecedented global loss in biodiversity. To counteract these trends, it is essential to develop systems to monitor changes in biodiversity for planning, evaluating, and implementing conservation and mitigation actions. However, the implementation of monitoring systems suffers from a trade-off between grain (i.e., the level of detail), extent (i.e., the number of study sites), and temporal repetition. Here, we present an applied and realized networked sensor system for integrated biodiversity monitoring in the Nature 4.0 project as a solution to these challenges, which considers plants and animals not only as targets of investigation, but also as parts of the modular sensor network by carrying sensors. Our networked sensor system consists of three main closely interlinked components with a modular structure: sensors, data transmission, and data storage, which are integrated into pipelines for automated biodiversity monitoring. We present our own real-world examples of applications, share our experiences in operating them, and provide our collected open data. Our flexible, low-cost, and open-source solutions can be applied for monitoring individual and multiple terrestrial plants and animals as well as their interactions. Ultimately, our system can also be applied to area-wide ecosystem mapping tasks, thereby providing an exemplary cost-efficient and powerful solution for biodiversity monitoring. Building upon our experiences in the Nature 4.0 project, we identified ten key challenges that need to be addressed to better understand and counteract the ongoing loss of biodiversity using networked sensor systems. To tackle these challenges, interdisciplinary collaboration, additional research, and practical solutions are necessary to enhance the capability and applicability of networked sensor systems for researchers and practitioners, ultimately further helping to ensure the sustainable management of ecosystems and the provision of ecosystem services.

Synthesis of thieno[2,3-b]pyridinones acting as cytoprotectants and as inhibitors of [3H]glycine binding to the N-methyl-D-aspartate (NMDA) receptor.

The standard glycine site antagonist of the N-methyl-D-aspartate (NMDA) receptor, 3-phenyl-4-hydroxyquinolin-2(1H)-one (21), was used as a template for bioisostere benzene/thiophene exchange. Phenylacetylation of aminothiophene carboxylic acid methyl esters and subsequent cyclization delivered the three possible thienopyridinone isomers. 4-Hydroxy-5-phenylthieno[2,3-b]pyridin-6(7H)-one (3a), with the shortest distance between the sulfur and the nitrogen atom, was the most potent isomer (K(i) against the binding of [(3)H]glycine to rat membranes 16 microM), comparable in potency to the model quinolinone (21, 12 microM). Replacement of the phenyl substituent of 21 by a 2-thienyl residue resulted in a 2-5-fold loss in potency and was abandoned. In the thieno part of the thienopyridinone nucleus, the most successful substituents were halogen (Cl or Br) close to the sulfur atom and short alkyl chains at the other position, resulting in 7h, 8h, 8i, and 8m, with K(i) values between 5.8 and 10.5 nM. Introduction of a 3'-phenoxy moiety yielded several compounds with still higher potencies (18h, 18i, 18l, and 18m; K(i) between 1.1 and 2.0 nM). Quantitative structure-activity relationship (QSAR) calculations resulted in a consistent interpretation of the potencies of most compounds. Several of these 3'-phenoxy derivatives protected mouse fibroblast cell lines with transfected NMDA receptors from glutamate-induced toxicity. In addition, we report in vivo results for four of these compounds.

Clinal genetic variation and the 'rare allele phenomenon' in random mating populations of Urophora cardui (Diptera: Tephritidae).

In the present study we investigate a contact zone between two population groups of the tephritid fly Urophora cardui. We investigate scenarios that may have produced the genetic differentiation of the two groups, and we describe the 'rare allele phenomenon' from the contact zone. The rare allele phenomenon refers to alleles that are found at high frequency in contact zones but are rare or lacking outside the contact zone. The phenomenon is often observed in hybrid zones between subspecies of limited reproductive compatibility, but seldom in populations with random mating. Clinal genetic variation was observed at three loci in the contact zone. Three alleles at the locus Aat showed steep clines, between 20-70 km wide. A rare Aat-A allele occurred at high frequency in the centre of the contact zone. Two further loci, Hk and Pgd, showed less steep clinal genetic variation, the transition being in and slightly south of the centre of the Aat cline. Populations showed Hardy-Weinberg proportions and there was no evidence for linkage disequlibrium. These findings suggest random mating and gradual introgression between the population systems, which may originate from at least two range expansions. Aat's steep clines and rare allele may indicate selection on Aat alleles, although we presently can not quantify any agents. Because U. cardui experiences random mating in the contact zone with no apparent 'hybrid' incompatibility, mating experiments offer the possibility for future enquiries about the genetic basis of the rare allele phenomenon.

Inhibition of the functional expression of N-methyl-D-aspartate receptors in a stably transformed cell line by cyclosporin A.

The L(tk-) cell line L12-G10 stably transformed with the human N-methyl-D-aspartate (NMDA) receptor subunits NR1-1a/NR2A showed a Ca(2+)-dependent increase in cell death, loss of mitochondrial membrane potential, and ATP depletion after agonist stimulation. Treatment of the cells with cyclosporine A (CsA) for 4h reduced glutamate-induced cell death by 60% (IC(50) of 7.1microM). The immunophilin binding drug FK506 was not effective. Short preincubation with CsA for 10 min already decreased the glutamate-induced loss of mitochondrial membrane potential while the NMDA receptor function is not affected. However, pretreatment of the cells with CsA (30 microM) for 6h reduced membrane associated NR1-1a protein amount by approximately 85%, whereas mRNA expression remained unaffected. These results suggest, that the cytoprotective effect of CsA in L12-G10 cells is due to the inhibition of the permeability transition pore on the one hand and to the inhibition of the expression of functional NMDA receptors by an additional posttranscriptional mechanism on the other hand.

A simple cell line based in vitro test system for N-methyl-D-aspartate (NMDA) receptor ligands.

The generation of cell lines stably expressing the functional recombinant N-methyl-D-aspartate (NMDA) receptors (NRs) and their use for ligand testing in a simple excitotoxicity model is described. The mouse fibroblast cell line L(tk-) was co-transfected stably with cDNAs encoding the human NR subunits, NR1-1a/NR2A or NR1-1a/NR2B, respectively. The NR expression and functionality in resulting clones have been verified by RT-PCR, Western blotting, immunocytochemistry and fluo-4 calcium imaging. Stimulation of NR expressing clones with L-glutamate and glycine resulted in necrosis of cultures within 1 h. Therefore, a lactate dehydrogenase-based excitotoxicity assay was used for the pharmacological characterisation. The two selected clones exhibited pharmacological properties corresponding to the distinct NR subunit assemblies. Both cell lines showed proton inhibition of cell death in the range of physiological pH. EC50-values for L-glutamate under saturated D-serine concentrations were 3.7 microM for L12-G10 (NR1-1a/NR2A) and 2.8 microM for L13-E6 (NR1-1a/NR2B), respectively. Competitive antagonists (RS)-APV and (RS)-CPP as well as glycine B site antagonist DCKA prevented L-glutamate/glycine-induced cell death. NR2B selective antagonists such as ifenprodil or haloperidol did only protect L13-E6 cells. Spermine (300 microM) triggered cell death selectively in the L13-E6 clone in a pH-dependent manner.