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Single-crystal X-ray study of Ba2Cu2Te 4O11Br2 and its incommensurately modulated superstructure companion

Compounds containing lone-pair elements such as TeIV are very interesting from the structural point of view, as the lone-pair nonbonding regions create low-dimensional geometrical arrangements. We have synthesized two new compounds with these features - Ba2Cu2Te 4O11Br2 (I) and Ba2Cu 2Te4O11-δ(OH)2δBr 2 (II, δ ≈ 0.57) - as members of the AE-M-Te-O-X (AE = alkaline-earth metal, M = transition metal

All the disorder mechanisms in the 13:58 phases come together. Out of the modulated confusion rises the remarkable phase Ce12.60Cd 58.68(2)

The compound Ce12.60Cd58.68(2) is a metrically commensurate representative of the incommensurately modulated phase Ce 13Cd57+δ. It is most likely a lock-in phase. The structure, which was solved using seeding of the modulation from those positions most affected as well as direct solution by charge flipping, represents a rare case of ordering in a family of structures where disorder is the rule. Th

Quasicrystal approximant Ho13Zn 58 + δ (δ ≈ 0.6) : An incommensurate modulated tunnel structure

In a systematic study of the binary quasicrystal approximants RE13Zn58 (RE = rare earth elements) system, single crystals of Ho13Zn58 + have been prepared. It is unique among family members of the RE13Zn58 system in that it shows a modulated superstructure ordering. Satellite reflections observed in single crystal X-ray diffraction pattern indicate the presence of a one-dimensional lattice distort

Single-crystal growth and structure determination of misfit layer oxide [Sr2TlO3][CoO2]1.77

We have synthesized single crystals of the misfit layer cobaltate [Sr2TlO3][CoO2]1.77 and determined its crystal structure by the means of X-ray single-crystal diffraction (XRSD) and transmission electron microscopy. The synthesis took place by spontaneous crystallization from an oxide melt at high gaseous pressure. The structure is described by two monoclinic subsystems, which share the unit cell

The crystal structure of CuSb2O3Br : Slabs from cubic Sb2O3 interspersed between puckered hexagonal CuBr-type layers

The new compound CuSb2O3Br crystallize in the monoclinic space group Cc. The unit cell parameters are a=7.9189(15)Å, b=13.7105(10)Å, c=19.048(2)Å, β=90°, Z=16. The crystal structure is solved from single crystal data, R=0.0490. The compound show a layered structure with slabs from cubic Sb2O3 interspersed in between puckered layers of CuBr. The Sb(III) atoms have tetrahedral [SbO3E] coordination w

Site occupancy wave and charge density wave in the modulated structure of Nd0.6Gd0.4Se1.85

Single crystals of Nd0.6Gd0.4Se1.85 have been prepared by chemical transport reactions starting from pre-annealed powder samples. Satellite reflections observed in X-ray and electron diffraction experiments indicate the presence of a two-dimensional lattice distortion. The origin of this is a site occupancy wave and, coupled to this, a charge density wave in the planar selenium layer of this compo

Trap-aware compact modeling and power-performance assessment of III-V tunnel FET

We report, for the first time, on a SPICE simulation study of the circuit-level power-performance impact of device traps in a state-of-the-art III-V heterojunction tunnel FET (TFET). First, the individual parasitic effects of junction bulk traps and oxide interface traps are incorporated in a compact model and validated against measurement-calibrated TCAD data, where we propose an analytical formu

Temporomandibular pain in adolescents with a history of preterm birth

Aim: To evaluate the frequency of temporomandibular disorder (TMD) pain among adolescents with a history of preterm birth compared to a matched control group. Methods: A group of 192 preterm-born adolescents was followed up at the age of 17-19 years and compared to matched controls. Self-report questionnaires included screening questions about TMD pain, chronic diseases, general health, depression

Besattheten att beröra förlamar teatern

IRedan 1990 skrev teaterkritikern Leif Zern att ”Årets kritiska klyscha har med kraft hunnit etablera sig: berörd. Det går inte en dag utan att någon recensent påstår sig vara berörd eller oberörd”. Nästan 30 år senare är termen fortfarande en kraftfull kvalitetsmarkör i teaterdiskussionen. Det intressanta är att denna kvalitet, att beröras, ofta ses som ett så självklart kriterium på den goda tea

Expression of PD-L1 and PD-1 in chemoradiotherapy-Naïve esophageal and gastric adenocarcinoma : Relationship with mismatch repair status and survival

Background: The outlook for patients with esophageal and gastric (EG) cancer remains poor. Hence, there is a compelling need to identify novel treatment strategies and complementary biomarkers. Programmed death ligand 1 (PD-L1) and mismatch repair deficiency (dMMR) are putative biomarkers of response to immune-checkpoint blockade, but their prognostic value and interrelationship in EG cancer have

Stability and behaviour in aqueous solutions of the anionic cubic silsesquioxane substituted with tetramethylammonium

The aqueous behaviour of the anionic octa-tetramethylammonium substituted cubic silsesquioxane, [N(CH 3 ) 4 ] 8 [Si 8 O 20 ], was studied with quantitative 29 Si-NMR. This molecule partially fragments in aqueous solutions, forming several smaller entities. The most abundant silica species are the monomer, dimer, cyclic trimer, cyclic tetramer and double three-ring. Higher concentrations are

A physiological perspective on the ecology and evolution of partial migration

Billions of animals migrate between breeding and non-breeding areas worldwide. Partial migration, where both migrants and residents coexist within a population, occurs in most animal taxa, including fish, insects, birds and mammals. Partial migration has been hypothesised to be the most common form of migration and to be an evolutionary precursor to full migration. Despite extensive theoretical mo

Sharing Cities : Exploring the Emerging Landscape of the Sharing Economy in Cities

Sharing Cities Sweden aims to put Sweden on the map as a country that actively and critically works with the sharing economy in cities. The objectives of the program are to develop world-leading test-beds for the sharing economy in Stockholm, Gothenburg, Malmö and Umeå as well as develop a national node to significantly improve national and international cooperation and promote an exchange of expe

Aboveground insect herbivory increases plant competitive asymmetry, while belowground herbivory mitigates the effect

Insect herbivores can shift the composition of a plant community, but the mechanismunderlying such shifts remains largely unexplored. A possibility is that insects alter thecompetitive symmetry between plant species. The effect of herbivory on competitionlikely depends on whether the plants are subjected to aboveground or belowgroundherbivory or both, and also depends on soil nitrogen levels. It i

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Intern kommunikation är ett område som oftast har negligerats bland såväl forskare som praktiker. Merparten av forskningen och praktiken inom kriskommunikation har fokuserats på extern kommunikation vilket kan förklaras med att de flesta forskare inom fältet har sin bakgrund inom public relations och att den externa kommunikationen många gånger är mer tydlig för praktikerna. Men att intern kriskom

Alternative splicing and ACMG-AMP-2015-based classification of PALB2 genetic variants : An ENIGMA report

Background: PALB2 monoallelic loss-of-function germ-line variants confer a breast cancer risk comparable to the average BRCA2 pathogenic variant. Recommendations for risk reduction strategies in carriers are similar. Elaborating robust criteria to identify loss-of-function variants in PALB2 - without incurring overprediction - is thus of paramount clinical relevance. Towards this aim, we have perf

Cu20Sb35O44Br37 - one structure, two temperature dependencies

The structure of the new compound Cu20Sb35O44Br37 was examined at different temperatures and compared to the previously prepared structural analogue Cu20Sb35O44Cl37. The structure comprises two major units; isolated [Sb35O44Br5]12+ clusters shaped as typical sodalite building blocks (β-cages) and one-dimensional continuous CuBr chains of edge sharing super-tetrahedra. The covalent and ionic buildi