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The success of invasive plant species can be evaluated using different dimensions, such as, range size, abundance and impact. These different dimensions do not always covary but are rarely separated, suggesting an urgency to disentangle the functional mechanisms behind them.A dataset of leaf traits and four dimensions of invasion success (i.e. range size, local abundance, impact on native plant abundance and impact on native plant diversity) were compiled for 395 non‐native plant species in the US and Europe. Associations among dimensions of invasion success and between leaf traits and dimensions were analysed with general linear models (LMs) and supplemented by phylogenetic generalized least square (PGLS) models, which control for the phylogenetic relatedness across species.The pair‐wise associations between most pairs of invasion dimensions were weak or neutral. The only exception was the association between impact on native plant abundance and impact on native plant diversity, which was strongly positive. Traits of species that have large range sizes were associated with a high metabolic rate; whereas, traits of species that were abundant or had a strong impact at the local scale were associated with low metabolic rate. In addition, traits of species with a large range size or having strong impacts on native plant abundance were associated with acquisitive strategies; whereas, traits of species with a high local abundance or strong impacts on native plant diversity were associated with conservative strategies.Synthesis. Different dimensions of invasion success were associated with different functional traits. Invasion success at the regional scale was related to traits that promote rapid colonization; whereas, invasion success at the local scale was related to traits that are potentially less preferred by herbivores. Some locally successful invaders even possessed traits that facilitate a high stress tolerance and conservative strategy, which were similar to locally abundant native species. Therefore, an ambiguous definition of 'invasion success' in mechanism‐related studies may produce inconsistent or even controversial conclusions, highlighting the importance of separately studying different dimensions of invasion success. [ABSTRACT FROM AUTHOR]

Some invasive plant species rapidly evolve greater size and/or competitive ability in their nonnative ranges. However, it is not well known whether these traits transfer back to the native range, or instead represent genotype‐by‐environment interactions where traits are context specific to communities in the new range where the evolution occurred. Insight into transferability vs. context specificity can be tested using experiments performed with individuals from populations from the native and nonnative ranges of exotic invasive species. Using a widespread invasive plant species in Europe, Solidago gigantea, we established reciprocal common garden experiments in the native range (Montana, North America; n = 4) and the nonnative range (Hungary, Europe; n = 4) to assess differences in size, vegetative shoot number, and herbivory between populations from the native and nonnative ranges. In a greenhouse experiment, we also tested whether the inherent competitive ability of genotypes from 15 native and 15 invasive populations differed when pitted against 11 common native North American competitors. In common gardens, plants from both ranges considered together produced five times more biomass, grew four times taller, and developed five times more rhizomes in the nonnative range garden compared to the native range garden. The interaction between plant origin and the common garden location was highly significant, with plants from Hungary performing better than plants from Montana when grown in Hungary, and plants from Montana performing better than plants from Hungary when grown in Montana. In the greenhouse, there were no differences in the competitive effects and responses of S. gigantea plants from the two ranges when grown with North American natives. Our results suggest that S. gigantea might have undergone rapid evolution for greater performance abroad, but if so, this response does not translate to greater performance at home. [ABSTRACT FROM AUTHOR]

In this work we demonstrate that time domain techniques can be used successfully to monitor realtively weak modulations of the fluorescence in sensing applications. The metal sensing complex Newport Green DCF™ can detect selected transition metals in vivo as well as in vitro. Incremental addition of Ni and/or Zn (in vitro) lead to a substantial reduction in the yield of the fast component in a bi-exponential fluorescence decay (τ1 = 150-250 ps) from 60% to 30-35%. This is rationalised as an inhibition of intra-molecular electron transfer in the NPG sensing complex due to metal complexation. In order to explore this effect in cellulo, NIH 3 T3 mouse skin fibroplast cells were pre-incubated with set levels of Ni and Zn, at a constant concentration of NPG. The fluorescence modulation in cellullo was subsequently studied employing both time-resolved fluorescence microscopy and confocal fluorescence microscopy. In correlation with the in vitro observations, similar effects were observed on the fluorescence decay in cellulo. [ABSTRACT FROM AUTHOR]

A luminescent europium probe has been discovered that binds selectively to drug-site I in human serum albumin, signalled by a ‘switching on’ of europium emission, and accompanied by strong induced circularly polarised luminescence. [ABSTRACT FROM AUTHOR]

Chiral image contrast is demonstrated using enantiopure Eu(iii) complexes that emit right or left-handed circularly polarised light of opposite sign, at selected wavelengths. [ABSTRACT FROM AUTHOR]

Four anionic europium complexes are described based on triazacyclononane tris-carboxylate or phosphinate ligands. In each case, the three sensitising chromophores comprise a substituted aryl-alkynyl pyridine group, with complex brightness in water falling in the range 4 to 23 m M−1 cm−1. para-Substitution of the aryl ring with carboxymethyl groups gives complexes that are taken into cells, stain the lysosomes selectively and unexpectedly permit lifetime measurements of lysosomal pH. In contrast, the introduction of sulfonate groups inhibits cell uptake enabling the Eu complex to be used as an extracellular donor for FRET applications at the membrane surface. Using time-gated FRET microscopy, the cell membrane structure was highlighted, in which Cell Mask Deep Red was used as a membrane- localized FRET acceptor. [ABSTRACT FROM AUTHOR]

Traditionally managed village yards have been disappearing from the Central-European countryside. Their lawn flora is likely to provide a unique habitat for many plants that are adapted to this environment. Composition of lawn flora was investigated in differently managed village yards (i.e., regularly mown and regularly trampled yards, poultry yards, paved yards) in southwestern Hungary. The main goal of the study was to detect the impacts of these different management regimes on the composition and diversity of the vegetation. In total, 240 1-m plots were sampled in 60 yards ranging from 80 m to 5,000 m in size. In the redundancy analysis, eight significant variables (degree of southness, slope, age, total size of yards; mowing, trampling and grazing regime; and the number of dogs) explained 16 % of the total variation in species data. The most diverse flora across yards was detected in the paved ones, and their stands also proved to be the most compositionally distinctive. In contrast, presence of domestic animals can contribute to local species loss as well as to a decrease in within-yard-type variability. These results highlight the importance of certain anthropogenic disturbances in maintaining high plant diversity, but also underline the crucial role of small-scale land management practices in rural environments. [ABSTRACT FROM AUTHOR]

A series of Eu and Tb complexes of four different chiral ligands incorporating an azaxanthone sensitiser has been evaluated as probes for the bicarbonate anion. Their binding affinities were assessed at ambient pH with bicarbonate, lactate, citrate, phosphate and serum albumin. Binding was signalled by modulation of circularly polarised luminescence and apparent affinity constants were measured by examining changes in emission intensity ratios. Competition experiments show that with these species and ATP present at normal physiological values, bicarbonate can be determined selectively over the concentration range 10 to 35 m M. Bicarbonate levels are also reported by using a mixture of Eu and Tb complexes of a common ligand, examining the ratio of red/green emitted light. These methods have been adapted for the determination of bicarbonate in human serum and used for the assessment of mitochondrial levels of bicarbonate in several different cell types with confocal microscopy. [ABSTRACT FROM AUTHOR]

Abstract: This work aims to develop and validate a rapid analytical method that enables the measurement of citrate in seminal fluid samples. Samples were obtained from men who were within 9 weeks of a vasectomy operation. Two age ranges were examined, between 40–43 and 50–53 years old, with nearly 100 samples in each case. No patient clinical history was available for this anonymous study, simulating a random screening cohort. The concentration of citrate in 0.5μL seminal fluid samples was assessed, using a europium emission luminescence method. This involves the ratiometric analysis of two well-separated europium(III) emission bands. Spectral data were obtained using a time-gated spectrometer whose construction and modification is described. Citrate values were confirmed by independent measurements using a citrate lyase enzymatic assay and by 700MHz 1H NMR analysis of the seminal fluid. Citrate concentrations were not statistically different between age groups and averaged 35.0(±14.6)mM for the 40–43 group, and 28.2(±12.7)mM for the 50–53 cohort; in each case a polymodal distribution was observed. [Copyright &y& Elsevier]

Abstract: Synaptotagmin 7 (Syt 7) is a Ca2+ sensor implicated in the regulation of membrane fusion in vesicular transport, but its precise role in neurons is still a matter of controversy. Dopaminergic drugs have been shown to modulate its expression in the striatum. Here we investigate whether dopamine receptor agonist-up-regulation of Syt 7 mRNA is specifically involved in the pathophysiological adaptations of hypersensitive striatum by analyzing other dopaminergic neurons containing brain regions. We treated rats with systemic reserpine injections that rapidly depletes dopamine throughout the brain, but leaves dopaminergic neurons spared from destruction. We analyzed the effects of apomorphine, a D1 and D2 receptor agonist on Syt 7 mRNA expression in caudate putamen, nucleus accumbens, cingulate cortex, substantia nigra compacta, ventral tegmental area and hippocampus. The treatment with reserpine resulted in akinesia, catalepsy and rigidity and up-regulation of proenkephalin and down-regulation of preprotachykinin mRNA in caudate putamen, indicating a severe depletion. By acute treatment with apomorphine proenkephalin mRNA was down-regulated and preprotachykinin mRNA up-regulated in the caudate putamen of reserpinized rats. Apomorphine increased Syt 7 mRNA levels only in striatum (caudate putamen and nucleus accumbens) of reserpinized rats, while in other brain regions it did not have such effect. The reserpinization and/or apomorphine treatment had no effect on Syt 1 mRNA expression in caudate putamen. It may be concluded, that in the striatum depleted of biogene amines, such as occurs after reserpine treatment, the up-regulation of Syt 7 could play a specific role as part of hypersensitive response to dopaminergic agonists. [Copyright &y& Elsevier]

A ratiometric EuIII complex has been developed that localises selectively within the endoplasmic reticulum of living cells. Careful calibration, using a time-gated spectral imaging microscope, allows the intensity ratio of emission bands and the variation of excited state lifetime to be used for pH determination, with a pKa of 7.15. [ABSTRACT FROM AUTHOR]

A terbium complex has been designed that may be used to sensitise formation of singlet oxygen (ϕem 12%), allowing the creation of a ratiometric sensory system for pO2 (versus the insensitive Eu analogue) and the definition of a reactive probe that can be used to cause local damage to cells loaded with the complex and exposed to laser excitation. [ABSTRACT FROM AUTHOR]

A terbium complex has been designed that may be used to sensitise formation of singlet oxygen (em12%), allowing the creation of a ratiometric sensory system for pO2(versusthe insensitive Eu analogue) and the definition of a reactive probe that can be used to cause local damage to cells loaded with the complex and exposed to laser excitation. [ABSTRACT FROM AUTHOR]

Summary: Understanding how widespread species adapt to variation in abiotic conditions across their ranges is fundamental to ecology. Insight may come from studying how among‐population variation (APV) in the common garden corresponds with the environmental conditions of source populations. However, there are no such studies comparing native vs non‐native populations across multiple life stages.We examined APV in the performance and functional traits of 59 Conyza canadensis populations, in response to drought, across large aridity gradients in the native (North America) and non‐native (Eurasia) ranges in three experiments. Our treatment (dry vs wet) was applied at the recruitment, juvenile, and adult life stages.We found contrasting patterns of APV in drought responses between the two ranges. In the native range, plant performance was less reduced by drought in populations from xeric than mesic habitats, but such relationship was not apparent for non‐native populations. These range‐specific patterns were consistent across the life stages.The weak adaptive responses of non‐native populations indicate that they can become highly abundant even without complete local adaptation to abiotic environments and suggest that long‐established invaders may still be evolving to the abiotic environment. These findings may explain lag times in invasions and raise concern about future expansions. [ABSTRACT FROM AUTHOR]

The synthesis of a family of chiral and enantiomerically pure pyridyl‐diamide (pda) ligands that upon complexation with europium [Eu(CF3SO3)3] result in chiral complexes with metal centered luminescence is reported; the sets of enantiomers giving rise to both circular dichroism (CD) and circularly polarized luminescence (CPL) signatures. The solid‐state structures of these chiral metallosupramolecular systems are determined using X‐ray diffraction showing that the ligand chirality is transferred from solution to the solid state. This optically favorable helical packing arrangement is confirmed by recording the CPL spectra from the crystalline assembly by using steady state and enantioselective differential chiral contrast (EDCC) CPL Laser Scanning Confocal Microscopy (CPL‐LSCM) where the two enantiomers can be clearly distinguished. [ABSTRACT FROM AUTHOR]

A set of four luminescent EuIII complexes bearing an extended aryl‐alkynylpyridine chromophore has been studied, showing very different pH‐dependent behaviour in their absorption and emission spectral response. For two complexes with pKa values of 6.45 and 6.20 in protein‐containing solution, the emission lifetime increases very significantly following protonation. By varying the gate time during signal acquisition, the 'switch‐on' intensity ratio could be optimised, and enhancement factors of between 250 to 1330 were measured between pH 8 and 4. The best‐behaved probe showed no significant emission dependence on the concentration of endogenous cations, reductants, and serum albumin. It was examined in live‐cell imaging studies to monitor time‐dependent lysosomal acidification, for which the increase in observed image brightness due to acidification was a factor of 50 in NIH‐3T3 cells. [ABSTRACT FROM AUTHOR]

Understanding the factors that shape the circularly polarised luminescence (CPL) emission profiles of europium(III)‐based CPL emitters to have specific sign properties, e. g. monosignate individual CPL transitions, is key to design novel complexes for applications ranging from advanced security inks to bio‐probes for live cell imaging. In order to correlate structure and spectral characteristics, a photophysical and kinetic investigation has been conducted on a series of coordinatively saturated nine‐coordinate europium(III) systems based on 1,4,7‐triazacyclononane. We highlight that lanthanide emission is sensitive to changes in the ligand field by showing the linear dependence of total emission intensity ratios as a function of solvent polarity, for europium(III) complexes displaying an internal charge transfer (ICT) excited state. This sensitivity increases by a factor of 20 when studying changes in CPL spectra, rendering these complexes accurate probes of local polarity. Solvent polarity, solvent‐specific effects, and the nature of the chromophores' coordinating donor atoms strongly influence the kinetic stability of europium(III) complexes with respect to enantiomer interconversion. Notably, we show that the choice of donor groups to coordinating to europium(III) and the nature and polarity of the solvent affects the rate of racemisation, leading to systems with very long half‐lives at room temperature in non‐polar media. [ABSTRACT FROM AUTHOR]

EDTA is widely used as an inhibitor of bacterial growth, affecting the uptake and control of metal ions by microorganisms. We describe the synthesis and characterisation of two symmetrical bis‐amide derivatives of EDTA, featuring glycyl or pyridyl substituents: AmGly2 and AmPy2. Metal ion affinities (logK) have been evaluated for a range of metals (Mg2+, Ca2+, Fe3+, Mn2+, Zn2+), revealing less avid binding compared to EDTA. The solid‐state structures of AmGly2 and of its Mg2+ complex have been determined crystallographically. The latter shows an unusual 7‐coordinate, capped octahedral Mg2+ centre. The antibacterial activities of the two ligands and of EDTA have been evaluated against a range of health‐relevant bacterial species, three Gram negative (Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) and a Gram positive (Staphylococcus aureus). The AmPy2 ligand is the only one that displays a significant inhibitory effect against K. pneumoniae, but is less effective against the other organisms. AmGly2 exhibits a more powerful inhibitory effect against E. coli at lower concentrations than EDTA (<3 mm) or AmPy2, but loses its efficacy at higher concentrations. The growth inhibition of EDTA and AmGly2 on mutant E. coli strains with defects in outer‐membrane lipopolysaccharide (LPS) structures has been assessed to provide insight into the unexpected behaviour. Taken together, the results contradict the assumption of a simple link between metal ion affinity and antimicrobial efficacy. [ABSTRACT FROM AUTHOR]

Since the pioneering report by Selvin, we have been fascinated by the potential of using lanthanide luminescence in bioimaging. The uniquely narrow emission lines and long luminescence lifetimes both provide the potential for background free images together with full certainty of probe localization. General use of lanthanide based bioimaging was first challenged by low brightness, and later by the need of UV (<405 nm) excitation sources not present in commercial microscopes. Here, we designed three lanthanide‐based imaging probes based on a known motif to investigate the limitations of 405 nm excitation. These were synthesized, characterized, investigated on dedicated as well as commercial microscopes, and the photophysics was explored in detail. It was proven without doubt that the lanthanide complexes enter the cells and luminesce internally. Even so, no lanthanide luminescence were recovered on the commercial microscopes. Thus, we returned to the photophysical properties that afforded the conclusion that – despite the advances in light sources and photodetectors – we need new designs that can give us brighter lanthanide complexes before bioimaging with lanthanide luminescence becomes something that is readily done. [ABSTRACT FROM AUTHOR]

An RNA-based coordination polymer is formed by the aqueous reaction of CuI ions with the thionucleoside enantiomer (−)6-thioguanosine, (6tGH). The resulting polymer, [CuI(μ3-S-thioG)]n1, has a one-dimensional structure based on a [Cu4–S4] core and undergoes extensive hierarchical self-assembly transforming from oligomeric chains → rod → cable → bundle through which a fibrous gel forms, that undergoes syneresis to form a self-supporting mass. The assembly involves the formation of helical cables/bundles and, in combination with the intrinsic photoemission of the polymer, results in the material exhibiting circularly polarised luminescence (CPL). [ABSTRACT FROM AUTHOR]

Resistance and tolerance are two ways that plants cope with herbivory. Tolerance, the ability of a plant to regrow or reproduce after being consumed, has been studied less than resistance, but this trait varies widely among species and has considerable potential to affect the ecology of plant species. One particular aspect of tolerance, compensatory responses, can evolve rapidly in plant species; providing insight into interactions between consumers and plants. However, compensation by invasive species has rarely been explored. We compared compensatory responses to the effects of simulated herbivory expressed by plants from seven Solidago gigantea populations from the native North American range to that expressed by plants from nine populations from the nonnative European range. Populations were also collected along elevational gradients to compare ecotypic variation within and between ranges. Solidago plants from the nonnative range of Europe were more tolerant to herbivory than plants from the native range of North America. Furthermore, plants from European populations increased in total biomass and growth rate with elevation, but decreased in compensatory response. There were no relationships between elevation and growth or compensation for North American populations. Our results suggest that Solidago gigantea may have evolved to better compensate for herbivory damage in Europe, perhaps in response to a shift to greater proportion of attack from generalists. Our results also suggest a possible trade-off between rapid growth and compensation to damage in European populations but not in North American populations. [ABSTRACT FROM AUTHOR]

Two bright, europium(iii) complexes based on an achiral heptadentate triazacyclononane ligand bearing two strongly absorbing chromophores have been evaluated for the selective emission and CPL signalling of various chiral O-phosphono-anions. Binding of O-phosphono-Ser and Thr gives rise to a strong induced CPL signature and a favoured Δ complex configuration is adopted. A similarly large induced CPL signal arises when [Eu·L1]2+ binds to lysophosphatidic acid (LPA), where the strong binding (log K 5.25 (295 K)) in methanol allowed its detection over the range 5 to 40 μM. Strong and chemoselective binding to the phosphorylated amino-acid residues was also observed with a set of four structurally related hexapeptides: in one case, the sign of the gem value in the ΔJ = 1 transition allowed differentiation between the binding to O-P-Ser and O-P-Tyr residues. [ABSTRACT FROM AUTHOR]

Helically chiral boron‐chelated dipyrromethene (BODIPY) dyes are known to exhibit solution phase circularly polarized luminescence (CPL), but examples are limited to a few synthetically accessible molecular architectures. We report a B−N chelation, SNAr, Suzuki cross‐coupling, B−O chelation cascade reaction for the synthesis of understudied helically chiral, N,N,O,C‐boron chelated, "confused" BODIPYs, from readily accessible 3,5‐dibromo‐BODIPY starting materials. Using this approach we have prepared a series of helically chiral "confused" BODIPYs with variation of the 3,5‐subsitutents. Following resolution by chiral HPLC, absolute stereochemistry was assigned through comparison of the experimental and calculated ECD spectra, and solution phase chiroptical properties including CPL were determined (|glum| from 2.1 to 3.7×10−3; BCPL from 11.3 to 27.2). [ABSTRACT FROM AUTHOR]

The cellular localisation and binding specificity of two NMDAR-targeted near-IR imaging probes has been examined by microscopy, followed by exemplification of MSOT to monitor simulated glutamate bursts in cellulo and a preliminary study in mice observing the signal in the brain. [ABSTRACT FROM AUTHOR]

A series of bright, europium(iii) complexes has been prepared based on an achiral heptadentate triazacyclononane ligand bearing two strongly absorbing, coordinated aralkynyl pyridyl moieties. The binding of chiral carboxylates, including α-hydroxy acids such as lactate and mandelate, has been monitored by emission spectroscopy and is signalled by the switching on of strong circularly polarised emission. In each case, an R-chiral carboxylate gave rise to emission typical of a Δ complex, most clearly shown in the form of the ΔJ = 4 transition manifold around 700 nm. Variations in the sign and magnitude of the CPL allow the enantiomeric purity and absolute configuration of the acid to be assessed in a sample. Analysis of the relative energies of the parent aqua complexes and their stereoisomeric adducts has been aided by lifetime measurements and density functional theory calculations. [ABSTRACT FROM AUTHOR]

Synthetically straightforward π‐extension of helically chiral N,N,O,O‐boron chelated borondipyrromethenes (BODIPYs) has been achieved by incorporation of naphthyl rings into the BODIPY 3‐ and 5‐positions. The effect of this extension on the photophysical and chiroptical properties is strongly dependent on the regiochemistry of the naphthyl substituents (4 exo, 4 lin, 4 endo). The most helicene‐like regioisomer 4 endo is a near infra‐red (NIR) emitter (λemmax=751 nm) with an emission band between 675–875 nm, displaying circularly polarised luminescence (CPL) with a luminescence dissymmetry factor, |glum|=5.7×10−3 and CPL brightness, BCPL=27, rivalling the best NIR CPL‐emitting small organic molecules reported to date. [ABSTRACT FROM AUTHOR]

BINOL moieties of different electronic demand are useful blocks for enabling the photo-production and modulation of triplet excited states in readily-accesible BINOL-based O-BODIPY dyes from standard F-BODIPY precursors. The rapid and rational development of smarter triplet-enabling BODIPY dyes on the basis of this strategy (e.g., TADF biomarker 4a or room temperature phosphor 4g) paves the way for advancing photonic applications based on organic triplet photosensitizers. [ABSTRACT FROM AUTHOR]

A series of five europium(III) complexes has been prepared from heptadentate N5O2 ligands that possess a brightness of more than 10 m M−1 cm−1 in water, following excitation over the range λ=330-355 nm. Binding of several oxy anions has been assessed by emission spectral titrimetric analysis, with the binding of simple carboxylates, lactate and citrate involving a common ligation mode following displacement of the coordinated water. Selectivity for bicarbonate allows the rapid determination of this anion in human serum, with Kd=37 m M (295 K). The complexes are internalised quickly into mammalian cells and exhibit a mitochondrial localisation at early time points, migrating after a few hours to reveal a predominant lysosomal distribution. Herein, we report the synthesis and complexation behaviour of strongly emissive europium (III) complexes that bind oxy-anions in aqueous media with an affinity and selectivity profile that is distinctively different from previously studied systems. [ABSTRACT FROM AUTHOR]

A europium complex selectively staining the nucleolus of NIH 3T3, HeLa, and HDF cells is reported. This complex possesses not only the advantage of the long lifetime of europium emission (0.3 ms), but also a chromophore that allows excitation at a relatively long wavelength (λmax = 384 nm) and gives rise to an acceptable quantum yield (9%). The complex can be used both in live cell and fixed cell imaging, giving an average intracellular concentration on the order of 0.5 μM. Strong binding to serum albumin has been demonstrated by examination of the analogous gadolinium complex, studying relaxivity changes with increasing protein concentration. The intracellular speciation of the complex has been examined by circularly polarized emission spectroscopy and is consistent with the presence of more than one europium species, possibly protein bound. [ABSTRACT FROM AUTHOR]

Interactions among native and invasive species may affect management outcomes and goals. We implemented different mowing regimes to control the invasive Solidago gigantea and restore natural diversity, and also examined interactions between Solidago and a European native competitor, Tanacetum vulgare in the context of these regimes. Experimentally planted Tanacetum suppressed Solidago by 79% without management, and a suite of mowing management regimes reduced the density of Solidago by 80–98% when Tanacetum was absent. But, when Tanacetum was added, the density of the invader was not reduced by mowing. Put another way, in mowed plots with Tanacetum, Solidago was twofold to over fivefold denser than in mowed plots without Tanacetum. It is not clear why the effect of Tanacetum shifted from competition in the absence of disturbance to facilitation with intense management‐associated disturbance, but other studies suggest that Tanacetum may create plant–soil feedbacks that favor Solidago. Evidence shows similar shifts from competition to facilitation under mowing regimes for other species, but these are not mechanistically clear either. We speculate that mowing reduced competition from Tanacetum while leaving belowground facilitative effects unchanged, shifting the net effect of Tanacetum to facilitation. When single‐year mowed plots were abandoned for just 1 year, Solidago was twofold denser than in the control, thus maintaining treatments over time was important for successful management. Our results indicate that mechanical control may substantially alter biotic resistance gained from native competition. [ABSTRACT FROM AUTHOR]

Controlled formation of desired lanthanide supramolecular complexes is challenging because of the difficulties in predicting coordination geometry, as well as a labile coordination number. Herein, we explore the effect of ionic radii and linker length on supramolecular species formation. A helicate-to-tetrahedron transformation occurred between [Ln2L13] and [Ln4L16] (Ln = La, Sm, Eu, Gd, Tb and Lu). For six lanthanide ions, the unfavored tetrahedron [La4L16] can only be observed in a concentrated mixture with the helicate [La2L13] where no pure [La4L16] species was isolated via crystallization. For Sm, Eu, Gd, Tb, the [Ln4L16] supramolecular tetrahedron can be isolated via crystallization from diisopropyl ether. A similar result was also observed for Lu, but the tetrahedral structure was found to be relatively stable and transformed back to [Lu2L13] much slower upon dissolution. No tetrahedron formation was observed with L3 giving rise to only [Ln2L33] species, in which L3 contains a longer and more flexible linker compared with that of L1. Results show that the supramolecular transformation in these systems is governed by both the ionic radii as well as the ligand design. Special focus is on both [Eu2L13] and [Eu4L16] which form chiral entities and exhibit interesting circular polarized luminescence. Lanthanide-based supramolecular complexes have labile and hard-topredict chemical structures. Here the authors show controlled formation of either helicates or tetrahedron shaped cages based on the interplay between the metal ionic radius and the ligand composition. [ABSTRACT FROM AUTHOR]

Chirality is ubiquitous within biological systems where many of the roles and functions are still undetermined. Given this, there is a clear need to design and develop sensitive chiral optical probes that can function within a biological setting. Here we report the design and synthesis of magnetically responsive Circularly Polarized Luminescence (CPL) complexes displaying exceptional photophysical properties (quantum yield up to 31 % and |glum| up to 0.240) by introducing chiral substituents onto the macrocyclic scaffolds. Magnetic CPL responses are observed in these chiral EuIII complexes, promoting an exciting development to the field of magneto‐optics. The |glum| of the 5D0 → 7F1 transition increases by 20 % from 0.222 (0 T) to 0.266 (1.4 T) displaying a linear relationship between the Δglum and the magnetic field strength. These EuIII complexes with magnetic CPL responses, provides potential development to be used in CPL imaging applications due to improved sensitivity and resolution. [ABSTRACT FROM AUTHOR]

Chirality is ubiquitous within biological systems where many of the roles and functions are still undetermined. Given this, there is a clear need to design and develop sensitive chiral optical probes that can function within a biological setting. Here we report the design and synthesis of magnetically responsive Circularly Polarized Luminescence (CPL) complexes displaying exceptional photophysical properties (quantum yield up to 31 % and |glum| up to 0.240) by introducing chiral substituents onto the macrocyclic scaffolds. Magnetic CPL responses are observed in these chiral EuIII complexes, promoting an exciting development to the field of magneto‐optics. The |glum| of the 5D0 → 7F1 transition increases by 20 % from 0.222 (0 T) to 0.266 (1.4 T) displaying a linear relationship between the Δglum and the magnetic field strength. These EuIII complexes with magnetic CPL responses, provides potential development to be used in CPL imaging applications due to improved sensitivity and resolution. [ABSTRACT FROM AUTHOR]

The enemy release hypothesis (ERH) attributes the success of some exotic plant species to reduced top‐down effects of natural enemies in the non‐native range relative to the native range. Many studies have tested this idea, but very few have considered the simultaneous effects of multiple kinds of enemies on more than one invasive species in both the native and non‐native ranges. Here, we examined the effects of two important groups of natural enemies–insect herbivores and soil biota–on the performance of Tanacetum vulgare (native to Europe but invasive in the USA) and Solidago canadensis (native to the USA but invasive in Europe) in their native and non‐native ranges, and in the presence and absence of competition.In the field, we replicated full‐factorial experiments that crossed insecticide, T. vulgare–S. canadensis competition, and biogeographic range (Europe vs. USA) treatments. In greenhouses, we replicated full‐factorial experiments that crossed soil sterilization, plant–soil feedback, and biogeographic range treatments. We evaluated the effects of experimental treatments on T. vulgare and S. canadensis biomass.The effects of natural enemies were idiosyncratic. In the non‐native range and relative to populations in the native range, T. vulgare escaped the negative effects of insect herbivores but not soil biota, depending upon the presence of S. canadensis; and S. canadensis escaped the negative effects of soil biota but not insect herbivores, regardless of competition. Thus, biogeographic escape from natural enemies depended upon the enemies, the invader, and competition. Synthesis: By explicitly testing the ERH in terms of more than one kind of enemy, more than one invader, and more than one continent, this study enhances our nuanced perspective of how natural enemies can influence the performance of invasive species in their native and non‐native ranges. [ABSTRACT FROM AUTHOR]

Developing invasive plant management strategies is an important task in modern ecology, conservation biology and land management. Solidago gigantea is considered a problematic invader in Europe and Asia, where it forms dominant stands that can decrease species diversity. There is, therefore, an urgent need for effective management to reduce S. gigantea infestations and their negative impacts. We examined the efficacy of multiple approaches to S. gigantea management in Hungary. In our study, we evaluated the effect of several long‐term management techniques such as grazing, mowing and periodic flooding on the invader's density as well as native community diversity. In addition, we investigated the short‐ and long‐term effects of mowing combined with other treatment options, to estimate the influence of increased management intensity. Our results indicate that all tested management techniques had negative impacts on S. gigantea density. Short‐term mowing did not appear to improve species diversity in the resident community; however, all long‐term options improved species diversity. Moreover, combining treatments with mowing varied in its effectiveness; mowing once increased the efficacy of flooding, but decreased the efficacy of grazing, while mowing twice decreased efficacy of flooding. We suspect this is due to the increased intensity of disturbance, which does not allow for the natural recovery of communities, and after management ceases, invasion is able to re‐occur. Our results indicate that for effective management, we need to combine management options which act via different mechanisms, leading to cumulative positive effects on the resident community when applied at moderate levels. [ABSTRACT FROM AUTHOR]

The enantiomers of [EuL3]·3Cl, an analogue of Eu:BPEPC with a lowered energy excitation wavelength, serve as effective reference complexes for the calibration of circularly polarised luminescence (CPL) spectrometers. [ABSTRACT FROM AUTHOR]

Bright lanthanide based probes for optical bioimaging must rely on the antenna principle, where the lanthanide‐centred excited state is formed by a complex sensitization process. Efficient sensitization of lanthanide‐centred emission occurs via triplet states centred on the sensitizing chromophore. Here, the triplet state of thioxanthone chromophores is modulated by extending the π‐system. Three thioxanthone chromophores‐thioxanthone, benzo[c]thioxanthone, and naphtho[2,3‐c]thioxanthone were synthesised and characterised. The triplet state energies and lifetimes is found to change as expected, and two dyes are found to be suitable sensitizers for europium(iii) luminescence. Reactive derivatives of thioxanthone and benzo[c]thioxanthone were prepared and coupled to a 1,4,7,10‐tetraazacyclododecane‐1,4,7‐triacetic acid (DO3A) lanthanide binding pocket. The photophysics and the performance in optical bioimaging of the resulting europium(iii) complexes were investigated. It is concluded that while the energetics favour efficient sensitization, the solution structure does not. While it was found that the complexes are too lipophilic to be efficient luminescent probes for optical bioimaging, we successfully demonstrated bioimaging using europium(iii) luminescence following 405 nm excitation. [ABSTRACT FROM AUTHOR]

A series of four emissive europium complexes has been evaluated for the binding of glyphosate in various aqueous media, including river water and grain extracts. Binding selectivity toward inorganic phosphate and bicarbonate was enhanced by measuring samples at pH 5.9, above the pKa of glyphosate itself. The highest affinity was shown with [Eu·L1], which creates an exocyclic tripicolylamine moiety when one pyridine group dissociates from Eu. Glyphosate was bound selectively over dihydrogenphosphate, glycinate, aminomethylphosphonate and the related herbicide glufosinate. The complex was used to measure glyphosate over the range 5 to 50 μM, in river water and grain extracts. [ABSTRACT FROM AUTHOR]

Abstract: The ability to study cellular metabolism and enzymatic processes involving adenosine triphosphate (ATP) is impeded by the lack of imaging probes capable of signalling the concentration and distribution of intracellular ATP rapidly, with high sensitivity. We report here the first example of a luminescent lanthanide complex capable of visualizing changes in the concentration of ATP in the mitochondria of living cells. Four cationic europium(III) complexes [Eu.1–4]+ have been synthesized and their binding capabilities towards nucleoside polyphosphate anions examined in aqueous solution at physiological pH. Complexes [Eu.1]+ and [Eu.3]+ bearing hydrogen bond donor groups in the pendant arms showed excellent discrimination between ATP, ADP and monophosphate species. Complex [Eu.3]+ showed relatively strong binding to ATP (logKa=5.8), providing a rapid, long‐lived luminescent signal that enabled its detection in a highly competitive aqueous medium containing biologically relevant concentrations of Mg2+, ADP, GTP, UTP and human serum albumin. This EuIII complex responds linearly to ATP within the physiological concentration range (1–5 m m), and was used to continuously monitor the apyrase‐catalyzed hydrolysis of ATP to ADP in vitro. We demonstrate that [Eu.3]+ can permeate mammalian (NIH‐3T3) cells efficiently and localize to the mitochondria selectively, permitting real‐time visualization of elevated mitochondrial ATP levels following treatment with a broad spectrum kinase inhibitor, staurosporine, as well as depleted ATP levels upon treatment with potassium cyanide under glucose starvation conditions. [ABSTRACT FROM AUTHOR]

Abstract: Chiral organic fluorophores have significant promise in the development of efficient emitters of circularly polarized light. Herein we describe a helically chiral boron dipyrromethene (BODIPY) with a hitherto unreported N,N,O,C‐boron‐chelation motif, synthesised by means of a one‐pot boron metathesis, nucleophilic aromatic substitution (SNAr), Suzuki coupling, boron chelation, cascade reaction. Resolution of the racemic BODIPY (by preparative HPLC on a chiral stationary phase) allowed examination of the chiroptical properties of the resulting enantiomers (λmax(abs)=593 nm, λmax(em)=622 nm, ϵ=30 000  m−1 cm−1, φF=0.49, |glum|=3.7×10−3 (hexane)). This is the first example of circularly polarised emission from a non‐C2‐symmetric helically chiral N,N,O,C‐BODIPY and as such provides a valuable benchmark for future developments in this compound series. [ABSTRACT FROM AUTHOR]

A family of five benzene-1,3,5-tricarboxamide (BTA) compounds with varied side arm functionality [alkyl: n = 3, 4 and 5 chains; and ester and carboyxic acids] is reported. Investigations into their self-assembly behaviour revealed the extent to which minor changes in the side arm functionality can affect the structures formed. The carboxylic acid derivatives have a tendency to form gels, while the ester derivatives instead form crystalline phases with associated thermotropic phase transitions. The influence of the side chain length and terminal functional group is rationalised by a combination of single crystal X-ray diffraction studies and examinations of the bulk material properties. [ABSTRACT FROM AUTHOR]

Native plants commonly suffer from strong negative plant-soil feedbacks. However, in their non-native ranges species often escape from these negative feedbacks, which indicates that these feedbacks are generated by at least partially specialized soil biota. If so, introduced plants might evolve the loss of resistance to pathogens in their former native range, as has been proposed for the loss of resistance to specialized herbivores. We compared the magnitude of plant-soil feedbacks experienced by native and exotic genotypes of the perennial forb, Solidago gigantea. Feedbacks were assessed in soil collected across 14 sites sampled across the western part of Solidago' s native range in the US. Both native and exotic genotypes of Solidago suffered consistently negative and broadly similar plant-soil feedbacks when grown in North American soil. Although there was substantial variation among soils from different sites in the strength of feedbacks generated, the magnitude of feedbacks generated by North American genotypes of S. gigantea were strongly correlated with those produced in the same soil by European genotypes. Our results indicate that Solidago experiences strong negative soil feedbacks in native soil and that introduced genotypes of Solidago have not lost resistance to these negative effects of soil biota. Both genotypic and landscape-level effects can be important sources of variation in the strength of plant-soil feedbacks. [ABSTRACT FROM AUTHOR]

The development of the brightest luminescent europium(iii) complexes is traced, including analysis of the C3-symmetric core complex based on a functionalized triazacyclononane and identification of the most suitable strongly absorbing chromophore. Strategies for the synthesis of the complexes, including enantiopure analogues, are outlined and opportunities for applications in time-resolved microscopy and spectral imaging emphasised. Practicable examples are introduced, including selective organelle staining for cellular optical imaging at 65 nm resolution and the development of new bioassays using time-resolved FRET methods. [ABSTRACT FROM AUTHOR]

A series of europium and terbium complexes based on a functionalized triazacyclononane carboxylate or phosphinate macrocyclic ligand is described. The influence of the anionic group, that is, carboxylate, methylphosphinate, or phenylphosphinate, on the photophysical properties was studied and rationalized on the basis of DFT calculated structures. The nature, number, and position of electron-donating or electron-withdrawing aryl substituents were varied systematically within the same phenylethynyl scaffold in order to optimize the brightness of the corresponding europium complexes and investigate their two-photon absorption properties. Finally, the europium complexes were examined in cell-imaging applications, and selected terbium complexes were studied as potential oxygen sensors. [ABSTRACT FROM AUTHOR]

The impact of invasive species across their native and nonnative ranges is poorly quantified and this impedes a complete understanding of biological invasions., We compared the impact of the native North American plant, Conyza canadensis, which is invasive to Eurasia, on species richness at home and in a number of introduced regions through well replicated transcontinental field studies, glasshouse experiments and individual-based models., Our results demonstrated mostly negative relationships between C. canadensis abundance and native species richness in nonnative ranges, but either positive or no relationships in its native North American range. In glasshouse experiments, the total biomass of Conyza was suppressed more by species from its native range than by species from regions where it is nonnative, but the effects of Conyza on other species did not show a consistent biogeographical pattern. Finally, individual-based models led to the exclusion of Conyza from North American scenarios but to high abundances in scenarios with species from the nonnative ranges of Conyza., We illustrate biogeographical differences in the impact of an invader across regional scales and suggest that inherent differences in one specific aspect of competitive ability, tolerance to the effects of other species, may play some role in these differences. [ABSTRACT FROM AUTHOR]

The synthetic utility of europium complexes with three coordinated 4-bromopyridyl groups for chromophore elaboration has been assessed in palladium-catalysed Sonogashira coupling reactions, and in copper(I) mediated click reactions of the triazide derivative, generated in situ. The crystal structure of the Eu complex of a p-OMe-phenyl substituted triazole at 100 K is reported in which the pendant triazole sensitising moieties interdigitate in the solid-state lattice. The triazole complex can be separated into Δ and ∧ enantiomers by chiral HPLC but is weakly emissive in methanol (ε 5.5 mM-1 cm-1; λexc 320 nm; ϕ 0.2%), contrasting with a set of four alkynyl-aryl derivatives which are one thousand times brighter and absorb strongly with broad absorption maxima in the range 332 to 360 nm. An enantiopure europium complex gives an intense CPL signal in solution that is the strongest yet reported. [ABSTRACT FROM AUTHOR]

Mono-C-substitution of the 1,4,7-triazacyclononane ring induces formation of single enantiomers of Eu(iii) complexes with nonadentate N6O3 ligands. The absolute configuration of each complex is determined by the stereogenicity of the C-substituent, revealed by comparison of the sign and sequence of CPL transitions for a series of complexes. [ABSTRACT FROM AUTHOR]

Biogeographic experiments that test how multiple interacting factors influence exotic plant abundance in their home and recipient communities are remarkably rare. We examined the effects of soil fungi, disturbance and propagule pressure on seed germination, seedling recruitment and adult plant establishment of the invasive Centaurea stoebe in its native European and non-native North American ranges., Centaurea stoebe can establish virtual monocultures in parts of its non-native range, but occurs at far lower abundances where it is native. We conducted parallel experiments at four European and four Montana ( USA) grassland sites with all factorial combinations of ± suppression of soil fungi, ±disturbance and low versus high knapweed propagule pressure [100 or 300 knapweed seeds per 0.3 m × 0.3 m plot (1000 or 3000 per m2)]. We also measured germination in buried bags containing locally collected knapweed seeds that were either treated or not with fungicide., Disturbance and propagule pressure increased knapweed recruitment and establishment, but did so similarly in both ranges. Treating plots with fungicides had no effect on recruitment or establishment in either range. However, we found: (i) greater seedling recruitment and plant establishment in undisturbed plots in Montana compared to undisturbed plots in Europe and (ii) substantially greater germination of seeds in bags buried in Montana compared to Europe. Also, across all treatments, total plant establishment was greater in Montana than in Europe., Synthesis. Our results highlight the importance of simultaneously examining processes that could influence invasion in both ranges. They indicate that under 'background' undisturbed conditions, knapweed recruits and establishes at greater abundance in Montana than in Europe. However, our results do not support the importance of soil fungi or local disturbances as mechanisms for knapweed's differential success in North America versus Europe. [ABSTRACT FROM AUTHOR]

The greater abundance of some exotic plants in their nonnative ranges might be explained in part by biogeographic differences in the strength of competition, but these competitive effects have not been experimentally examined in the field. We compared the effects of neighbors on the growth and reproduction of spotted knapweed (Centaurea stoebe) in Europe, where it is native, and in Montana, where it is invasive. There were strong negative competitive effects of neighboring vegetation on C. stoebe growth and reproduction in Europe. In contrast, identical experiments in Montana resulted in insignificant impacts on C. stoebe. Although the mechanisms that produce this dramatic biogeographic difference in competitive outcome remain unknown, our results indicate that differences in net competitive interactions between ranges may contribute to the striking dominance of C. stoebe in parts of North America. [ABSTRACT FROM AUTHOR]

The majority of plant diversity in the boreal forest of northern Alberta, Canada is comprised of native understory plant species that are continuously facing competition from other species, including both undesirable native and weedy species. In oil sands mine reclamation, cover soils rich in organic matter are used to cap overburden materials. The aim of this study is to understand the role of weeds on different reclamation cover soils (forest floor-mineral mix and peat-mineral mix) and determine if they hinder the establishment of the native plant community. This study was conducted four growing seasons after site establishment in June 2019. At that time, both soil types had approximately 45% total cover, had 21 species per plot, and were composed of mainly native vegetation. Competition from non-native forbs (11% average cover, mainly Sonchus arvensis and Melilotus alba) did not seem to impact the development of the native vegetation community on either soil type given the high cover and richness of native forbs. However, native graminoids (predominantly Calamagrostis canadensis) were associated with reduced native forb cover and richness at graminoid cover greater than 17%. Overall, non-native forbs appeared to have little impact on the native forb community on either soil type while native graminoids had a negative influence. We suggest that the classification of what is considered an undesirable weedy species should be evaluated in the context of ecosystem management goals rather than simply the presence of non-native species. [ABSTRACT FROM AUTHOR]