The bacterium Neisseria meningitidis causes life-threatening disease worldwide, typically with a clinical presentation of sepsis or meningitis, but can be carried asymptomatically as part of the normal human oropharyngeal microbiota. The aim of this study was to examine N. meningitidis carriage with regard to prevalence, risk factors for carriage, distribution of meningococcal lineages and persistence of meningococcal carriage. Throat samples and data from a self-reported questionnaire were obtained from 2744 university students (median age: 23 years) at a university in Sweden on four occasions during a 12-month period. Meningococcal isolates were characterised using whole-genome sequencing. The carriage rate among the students was 9.1% (319/3488; 95% CI 8.2–10.1). Factors associated with higher carriage rate were age ≤22 years, previous tonsillectomy, cigarette smoking, drinking alcohol and attending parties, pubs and clubs. Female gender and sharing a household with children aged 0–9 years were associated with lower carriage. The most frequent genogroups were capsule null locus (cnl), group B and group Y and the most commonly identified clonal complexes (cc) were cc198 and cc23. Persistent carriage with the same meningococcal strain for 12 months was observed in two students. Follow-up times exceeding 12 months are recommended for future studies investigating long-term carriage of N. meningitidis.

Population genetic studies often overlook the evidence for variability and change in past material culture. Here, the authors use a Mesolithic example to demonstrate the importance of integrating archaeological evidence into the interpretation of the Scandinavian hunter-gatherer genetic group. Genetic studies conclude that this group resulted from two single-event dispersals into Scandinavia before 7500 BC. Archaeological evidence, however, shows at least six immigration events pre-dating the earliest DNA, and that the first incoming groups arrived in Scandinavia before 9000 BC. The findings underline the importance of conducting careful archaeological analysis of prehistoric human dispersal in tandem with the study of ancient population genomics.

We report the layer structure and composition in recently discovered TiN/SiN(001) superlattices deposited by dual-reactive magnetron sputtering on MgO(001) substrates. High-resolution transmission electron microscopy combined with Z-contrast scanning transmission electron microscopy, x-ray reflection, diffraction, and reciprocal-space mapping shows the formation of high-quality superlattices with coherently strained cubic TiN and SiN layers for SiN thickness below 7–10 Å. For increasing SiN layer thicknesses, a transformation from epitaxial to amorphous SiNx (x ⩾ 1) occurs during growth. Elastic recoil detection analysis revealed an increase in nitrogen and argon content in SiNx layers during the phase transformation. The oxygen, carbon, and hydrogen contents in the multilayers were around the detection limit (∼0.1 at.%) with no indication of segregation to the layer interfaces. Nanoindentation experiments confirmed superlattice hardening in the films. The highest hardness of 40.4 ± 0.8 GPa was obtained for 20-Å TiN with 5-Å-thick SiN(001) interlayers, compared to monolithic TiN at 20.2 ± 0.9 GPa.

In order to combine the merits of both HfO2 and Al2O3 as high-κ gate dielectrics for CMOS technology, high-κ nanolaminate structures in the form of either Al2O3/HfO2/Al2O3 or Al2O3/HfAlOx/Al2O3 were implemented in pMOSFETs and electrically and microstructurally charachterized. ALD TiN film was used as the metal gate electrodes for the pMOSFETs. After full transistor-processing including a rapid thermal processing step at 930 °C, the HfO2 film in the former nanolaminate was found to be crystallized. In contrast, the HfAlOx layer in the latter nanolaminate remained in the amorphous state. Both types of pMOSFETs exhibited a hysteresis as small as ∼20 mV in C-V characteristics in the bias range of +/− 2 V. They also showed a reduced gate leakage current. The pMOSFET with the Al2O3/HfAlOx/Al2O3 nanolaminate was characterized with a subthreshold slope of 77 mV/decade and a channel hole mobility close to the universal hole mobility curve. The pMOSFET with the Al2O3/HfO2/Al2O3, however, exhibited a subthreshold slope of 100 mV/decade and a ∼30% lower hole mobility than the universal curve.

At present, there is a consensus that various Stress Driven Rearrangement Instabilities (SDRI) are the implications of the mathematically rigorous theoretical Gibbs thermodynamics. Many applied researchers and practitioners believe that SDRI are also universal physical phenomena occurring over a large range of length scales and applied topics. There is a multitude of publications claiming experimental observation of the SDRI based phenomena. This opinion is challenged by other highly respected scholars claiming theoretical inconsistencies and multiple experimental counterexamples. Such an uncertainty is too costly for further progress on the SDRI topic. The ultimate goal of our project is to resolve this controversy.

The project includes experimental, theoretical, and numerical studies. Among various plausible manifestations of SDRI, the authors focused only on two most promising for which the validity of the SDRI has already been claimed by other researchers: a) stress driven corrugations of the solid-melt phase interface in macroscopic quantum 4He and b) the dislocation-free Stranski-Krastanov pattern of growth of semiconductor quantum dots. We devised a program and experimental set-ups for testing applicability of the SDRI mechanisms using the same physical systems as before but using implications of the SDRI theory for 2D patterning which have never been tested in the past.