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‘Sons of athelings given to the earth’: Infant Mortality within Anglo-Saxon Mortuary Geography

FOR 20 OR MORE YEARS early Anglo-Saxon archaeologists have believed children are underrepresented in the cemetery evidence. They conclude that excavation misses small bones, that previous attitudes to reporting overlook the very young, or that infants and children were buried elsewhere. This is all well and good, but we must be careful of oversimplifying compound social and cultural responses to childhood and infant mortality. Previous approaches have offered methodological quandaries in the face of this under-representation. However, proportionally more infants were placed in large cemeteries and sometimes in specific zones. This trend is statistically significant and is therefore unlikely to result entirely from preservation or excavation problems. Early medieval cemeteries were part of regional mortuary geographies and provided places to stage events that promoted social cohesion across kinship systems extending over tribal territories. This paper argues that patterns in early Anglo-Saxon infant burial were the result of female mobility. Many women probably travelled locally to marry in a union which reinforced existing social networks. For an expectant mother, however, the safest place to give birth was with experience women in her maternal home. Infant identities were affected by personal and legal association with their mother’s parental kindred, so when an infant died in childbirth or months and years later, it was their mother’s identity which dictated burial location. As a result, cemeteries central to tribal identities became places to bury the sons and daughters of a regional tribal aristocracy

Equilibrium Formation of Stable All‐Silicon Versions of 1,3‐Cyclobutanediyl

Main group analogues of cyclobutane‐1,3‐diyls are fascinating due to their unique reactivity and electronic properties. So far only heteronuclear examples have been isolated. Here we report the isolation and characterization of all‐silicon 1,3‐cyclobutanediyls as stable closed‐shell singlet species from the reversible reactions of cyclotrisilene c ‐Si3Tip4 (Tip=2,4,6‐triisopropylphenyl) with the N‐heterocyclic silylenes c ‐[(CR2CH2)(Nt Bu)2]Si: (R=H or methyl) with saturated backbones. At elevated temperatures, tetrasilacyclobutenes are obtained from these equilibrium mixtures. The corresponding reaction with the unsaturated N‐heterocyclic silylene c ‐(CH)2(Nt Bu)2Si: proceeds directly to the corresponding tetrasilacyclobutene without detection of the assumed 1,3‐cyclobutanediyl intermediate

Bildung Stabiler All‐Silicium Varianten von 1,3‐Cyclobutandiyl im Gleichgewicht

Hauptgruppenanaloga von 1,3‐Cyclobutandiylen faszinieren mit ihrer einzigartigen Reaktivität und ihren elektronischen Eigenschaften. Bisher sind allerdings nur heteronukleare Vertreter isoliert worden. Wir berichten hier über die Isolierung und Charakterisierung von All‐Silicium‐1,3‐Cyclobutandiylen als stabile Singulettspezies mit geschlossenschaliger Konfiguration aus den reversiblen Reaktionen von Cyclotrisilen c ‐Si3Tip4 (Tip=2,4,6‐Triisopropylphenyl) mit den N‐heterocyclischen Silylenen c ‐[(CR2CH2)(Nt Bu)2]Si: (R=H oder Methyl) mit gesättigten Grundgerüsten. Bei erhöhten Temperaturen werden aus diesen Gleichgewichtsmischungen Tetrasilacyclobutene erhalten. Die analoge Reaktion mit dem ungesättigten N‐heterocyclischen Silylen c ‐(CH)2(Nt Bu)2Si: verläuft direkt zum entsprechenden Tetrasilacyclobuten ohne Nachweis des angenommenen 1,3‐Cyclobutandiyl‐Zwischenprodukts

In vivo biocompatibility of a new hydrophobic coated Al/Al2O3 nanowire surface on stents

Background: Intima proliferation and in-stent restenosis is a challenging situation in interventional treatment of small vessel obstruction. Al/Al2O3 nanowires have been shown to accelerate vascular endothelial cell proliferation and migration in vitro, while suppressing vascular smooth muscle cell growth. Moreover, surface modification of Al/Al2O3 nanowires with poly[bis(2,2,2-trifluoromethoxy)phosphazene (PTFEP) coating enables further advantages such as reduced platelet adhesion. Therefore, the study's goal was to compare the biocompatibility of novel Al/Al2O3 + PTFEP coated nanowire bare-metal stents to uncoated control stents in vivo using optical coherence tomography (OCT), quantitative angiography and histomorphometric assessment. Methods: 15 Al/Al2O3 + PTFEP coated and 19 control stents were implanted in the cervical arteries of 9 Aachen minipigs. After 90 days, in-stent stenosis, thrombogenicity, and inflammatory response were assessed. Scanning electron microscopy was used to analyse the stent surface. Results: OCT analysis revealed that neointimal proliferation in Al/Al2O3 + PTFEP coated stents was significantly reduced compared to control stents. The neointimal area was 1.16 ± 0.77 mm2 in Al/Al2O3 + PTFEP coated stents vs. 1.98 ± 1.04 mm2 in control stents (p = 0.004), and the neointimal thickness was 0.28 ± 0.20 vs. 0.47 ± 0.10 (p = 0.003). Quantitative angiography showed a tendency to less neointimal growth in coated stents. Histomorphometry showed no significant difference between the two groups and revealed an apparent inflammatory reaction surrounding the stent struts. Conclusions: At long-term follow-up, Al/Al2O3 + PTFEP coated stents placed in peripheral arteries demonstrated good tolerance with no treatment-associated vascular obstruction and reduced in-stent restenosis in OCT. These preliminary in vivo findings indicate that Al/Al2O3 + PTFEP coated nanowire stents may have translational potential to be used for the prevention of in-stent restenosis

A Molecular Complex with a Formally Neutral Iron-germanide Motif (Fe2Ge2)

We report the synthesis and isolation of a stable complex containing the formally neutral Fe2Ge2 motif, which is stabilized by the coordination of an N-heterocyclic carbene to the germanium and carbon monoxide to the iron center. [(NHCiPr2Me2)GeFe(CO)4]2 is obtained by reduction of the NHCiPr2Me2-coordinated dichlorogermylene adduct with Fe(CO)4, which in turn is obtained from reaction of Fe2(CO)9 with GeCl2·NHCiPr2Me2 (NHCiPr2Me2 = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene). The solid state structure of the title compound reveals two distinct coordination modes for the Fe(CO)4 fragments: bridging (p-type) and terminal (s-type). In solution, the rapid equilibrium between the two modes was resolved by NMR at −35°C. Reaction with propylene sulfide at room-temperature affords the sulfide-bridged digermanium complex with two terminal Fe(CO)4 moieties.We report the synthesis and isolation of a stable complex containing the formally neutral Fe2Ge2 motif, which is stabilized by the coordination of an N-heterocyclic carbene to the germanium and carbon monoxide to the iron center. [(NHCiPr2Me2)GeFe(CO)4]2 is obtained by reduction of the NHCiPr2Me2-coordinated dichlorogermylene adduct with Fe(CO)4, which in turn is obtained from reaction of Fe2(CO)9 with GeCl2·NHCiPr2Me2 (NHCiPr2Me2 = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene). The solid state structure of the title compound reveals two distinct coordination modes for the Fe(CO)4 fragments: bridging (p-type) and terminal (s-type). In solution, the rapid equilibrium between the two modes was resolved by NMR at −35°C. Reaction with propylene sulfide at room-temperature affords the sulfide-bridged digermanium complex with two terminal Fe(CO)4 moieties.We report the synthesis and isolation of a stable complex containing the formally neutral Fe2Ge2 motif, which is stabilized by the coordination of an N-heterocyclic carbene to the germanium and carbon monoxide to the iron center. [(NHCiPr2Me2)GeFe(CO)4]2 is obtained by reduction of the NHCiPr2Me2-coordinated dichlorogermylene adduct with Fe(CO)4, which in turn is obtained from reaction of Fe2(CO)9 with GeCl2·NHCiPr2Me2 (NHCiPr2Me2 = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene). The solid state structure of the title compound reveals two distinct coordination modes for the Fe(CO)4 fragments: bridging (p-type) and terminal (s-type). In solution, the rapid equilibrium between the two modes was resolved by NMR at −35°C. Reaction with propylene sulfide at room-temperature affords the sulfide-bridged digermanium complex with two terminal Fe(CO)4 moieties