How to preserve a butterfly species within an urbanising settlement and its surroundings: a study of the scarce copper (<Emphasis Type="Italic">Lycaena virgaureae</Emphasis> L.) in southern Sweden

Urbanisation is a rapidly ongoing process worldwide with profound consequences for wildlife in urban and peri-urban areas. Species are affected by habitat loss, habitat alternation and degradation, fragmentation and increased human population and activity. Habitat loss can occur due to construction of housing and infrastructure in peri-urban areas and within urban areas due to compaction. Undeveloped areas can also be changed from ruderal land, wilderness areas or leftover green space to more formal and more intensively used urban green space. This study investigated a butterfly species, the scarce copper (Lycaena virgaureae L.), in an urbanising and expanding settlement in a rural location in southern Sweden. The scarce copper is still relatively common in Sweden, but has experienced severe decline in certain areas and in other parts of Europe. Patch occupancy and abundance of the species were investigated in 44 patches ranging from urban and peri-urban to rural locations. Habitats investigated were parks, urban grasslands managed for biodiversity by the local authority, unmanaged abandoned arable sites, road verges, meadows and pastures. In total, 624 sightings of scarce coppers were recorded. The highest abundances were observed in larger unmanaged patches and in meadows in peri-urban areas, while pastures had low abundances. In urban parks, no coppers were found. The smaller sites managed for biodiversity by the local authority within the settlement were often occupied by the scarce copper, although abundances were low (mean number of individuals 3?±?1.2). In patches which were cut, copper numbers dropped in almost all cases to zero after cutting. Patch occupancy was affected by habitat characteristics such vegetation height, tree succession, abundance of Rumex acetosella (sheep’s sorrel), as well as landscape features such as length of forest edge. Factors identified as influencing abundance were the same, but additionally also flower abundance. The current high abundances of the scarce copper in the area will not be ensured in the longer term when all building plans are implemented and no other measures are taken. Recommendations are made on management and planning to preserve the species in the study area.     

Flexible kinship: shaping transnational families among the Chinese in Tahiti

This article examines the practices of ‘flexible kinship’ used by Chinese migrants in colonial Tahiti. ‘Flexible kinship’ draws attention to the strategic uses that are made of kinship in the context of migration and diaspora: the adjustments to cultural, political, and legal borders that lead to changes in family forms and in the relations between kin. Using a multi‐generational perspective, I examine how families were shaped by successive changes and reversals in legal‐political and economic events and conjunctures over the long twentieth century. I argue for the importance of addressing transnational border‐crossing practices that involve not just a spatial extension of networks but also legal strategies within the host locality. I further show that if it is true that the Confucian hierarchical order has conditioned transnational practices of flexible kinship, then this hierarchy has not only bent to the circumstances, it has to a great extent been weakened. Finally, I argue that the history of familial adjustments has shaped a habitus that maximizes economic and legal security, especially among women.     

NEIL3-Dependent Regulation of Cardiac Fibroblast Proliferation Prevents Myocardial Rupture

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Development of a Multiple Loci Variable Number of Tandem Repeats Analysis (MLVA) to Unravel the Intra-Pathovar Structure of Pseudomonas syringae pv. actinidiae Populations Worldwide

The bacterial canker of kiwifruit by Pseudomonas syringae pv. actinidiae is an emblematic example of a catastrophic disease of fruit crops. In 2008 a new, extremely virulent form of the pathogen emerged and rapidly devastated many Actinidia spp. orchards all over the world. In order to understand differences in populations within this pathovar and to elucidate their diffusion and movements on world scale, it is necessary to be able to quickly and on a routine basis compare new isolates with previous records. In this report a worldwide collection of 142 strains was analyzed by MLVA, chosen as investigative technique for its efficacy, reproducibility, simplicity and low cost. A panel of 13 Variable Number of Tandem Repeats (VNTR) loci was identified and used to describe the pathogen population. The MLVA clustering is highly congruent with the population structure as previously established by other molecular approaches including whole genome sequencing and correlates with geographic origin, time of isolation and virulence. For convenience, we divided the VNTR loci in two panels. Panel 1 assay, using six loci, recognizes 23 different haplotypes, clustered into ten complexes with highest congruence with previous classifications. Panel 2, with seven VNTR loci, provides discriminatory power. Using the total set of 13 VNTR loci, 58 haplotypes can be distinguished. The recent hypervirulent type shows very limited diversity and includes, beside the strains from Europe, New Zealand and Chile, a few strains from Shaanxi, China. A broad genetic variability is observed in China, but different types are also retrievable in Japan and Korea. The low virulent strains cluster together and are very different from the other MLVA genotypes. Data were used to generate a public database in MLVAbank. MLVA represents a very promising first-line assay for large-scale routine genotyping, prior to whole genome sequencing of only the most relevant samples.     

αII-Spectrin Regulates Invadosome Stability and Extracellular Matrix Degradation

Invadosomes are actin-rich adhesion structures involved in tissue invasion and extracellular matrix (ECM) remodelling. αII-Spectrin, an ubiquitous scaffolding component of the membrane skeleton and a partner of actin regulators (ABI1, VASP and WASL), accumulates highly and specifically in the invadosomes of multiple cell types, such as mouse embryonic fibroblasts (MEFs) expressing SrcY527F, the constitutively active form of Src or activated HMEC-1 endothelial cells. FRAP and live-imaging analysis revealed that αII-spectrin is a highly dynamic component of invadosomes as actin present in the structures core. Knockdown of αII-spectrin expression destabilizes invadosomes and reduces the ability of the remaining invadosomes to digest the ECM and to promote invasion. The ECM degradation defect observed in spectrin-depleted-cells is associated with highly dynamic and unstable invadosome rings. Moreover, FRAP measurement showed the specific involvement of αII-spectrin in the regulation of the mobile/immobile β3-integrin ratio in invadosomes. Our findings suggest that spectrin could regulate invadosome function and maturation by modulating integrin mobility in the membrane, allowing the normal processes of adhesion, invasion and matrix degradation. Altogether, these data highlight a new function for spectrins in the stability of invadosomes and the coupling between actin regulation and ECM degradation.     

Astrocyte Sodium Signalling and Panglial Spread of Sodium Signals in Brain White Matter

In brain grey matter, excitatory synaptic transmission activates glutamate uptake into astrocytes, inducing sodium signals which propagate into neighboring astrocytes through gap junctions. These sodium signals have been suggested to serve an important role in neuro-metabolic coupling. So far, it is unknown if astrocytes in white matter—that is in brain regions devoid of synapses—are also able to undergo such intra- and intercellular sodium signalling. In the present study, we have addressed this question by performing quantitative sodium imaging in acute tissue slices of mouse corpus callosum. Focal application of glutamate induced sodium transients in SR101-positive astrocytes. These were largely unaltered in the presence of ionotropic glutamate receptors blockers, but strongly dampened upon pharmacological inhibition of glutamate uptake. Sodium signals induced in individual astrocytes readily spread into neighboring SR101-positive cells with peak amplitudes decaying monoexponentially with distance from the stimulated cell. In addition, spread of sodium was largely unaltered during pharmacological inhibition of purinergic and glutamate receptors, indicating gap junction-mediated, passive diffusion of sodium between astrocytes. Using cell-type-specific, transgenic reporter mice, we found that sodium signals also propagated, albeit less effectively, from astrocytes to neighboring oligodendrocytes and NG2 cells. Again, panglial spread was unaltered with purinergic and glutamate receptors blocked. Taken together, our results demonstrate that activation of sodium-dependent glutamate transporters induces sodium signals in white matter astrocytes, which spread within the astrocyte syncytium. In addition, we found a panglial passage of sodium signals from astrocytes to NG2 cells and oligodendrocytes, indicating functional coupling between these macroglial cells in white matter.