Probing the interplay between lattice dynamics and short-range magnetic correlations in CuGeO3 with femtosecond RIXS

Investigations of magnetically ordered phases on the femtosecond timescale have provided significant insights into the influence of charge and lattice degrees of freedom on the magnetic sub-system. However, short-range magnetic correlations occurring in the absence of long-range order, for example in spin-frustrated systems, are inaccessible to many ultrafast techniques. Here, we show how time-resolved resonant inelastic X-ray scattering (trRIXS) is capable of probing such short-ranged magnetic dynamics in a charge-transfer insulator through the detection of a Zhang-Rice singlet exciton. Utilizing trRIXS measurements at the O K-edge, and in combination with model calculations, we probe the short-range spin-correlations in the frustrated spin chain material CuGeO3 following photo-excitation, revealing a strong coupling between the local lattice and spin sub-systems

Examining the surface phase diagram of IrTe2_2 with photoemission

In the transition metal dichalcogenide IrTe$_2$, low-temperature charge-ordered phase transitions involving Ir dimers lead to the occurrence of stripe phases of different periodicities, and nearly degenerate energies. Bulk-sensitive measurements have shown that, upon cooling, IrTe$_2$ undergoes two such first-order transitions to $(5\times1\times5)$ and $(8\times1\times8)$ reconstructed phases at $T_{c_1}\sim 280$~K and $T_{c_2}\sim 180$~K, respectively. Here, using surface sensitive probes of the electronic structure of IrTe$_2$, we reveal the first-order phase transition at $T_{c_3}=165$~K to the $(6\times1)$ stripes phase, previously proposed to be the surface ground state. This is achieved by combining x-ray photoemission spectroscopy and angle-resolved photoemission spectroscopy, which give access to the evolution of stripe domains and a particular surface state, the energy of which is dependent on the Ir dimer length. By performing measurements over a full thermal cycle, we also report the complete hysteresis of all these phases

Phase separation in the vicinity of Fermi surface hot spots

Spatially inhomogeneous electronic states are expected to be key ingredients for the emergence of superconducting phases in quantum materials hosting charge-density waves (CDWs). Prototypical materials are transitionmetal dichalcogenides (TMDCs) and among them, 1T-TiSe2 exhibiting intertwined CDW and superconducting states under Cu intercalation, pressure, or electrical gating. Although it has been recently proposed that the emergence of superconductivity relates to CDW fluctuations and the development of spatial inhomogeneities in the CDW order, the fundamental mechanism underlying such a phase separation (PS) is still missing. Using angle- resolved photoemission spectroscopy and variable-temperature scanning tunneling microscopy, we report on the phase diagram of the CDW in 1T-TiSe2 as a function of Ti self-doping, an overlooked degree of freedom inducing CDW texturing. We find an intrinsic tendency towards electronic PS in the vicinity of Fermi surface (FS) “hot spots,” i.e., locations with band crossigs close to, but not at the Fermi level.We therefore demonstrate an intimate relationship between the FS topology and the emergence of spatially textured electronic phases which is expected to be generalizable to many doped CDW compound

Sensitive Monogenic Noninvasive Prenatal Diagnosis by Targeted Haplotyping

During pregnancy, cell-free DNA (cfDNA) in maternal blood encompasses a small percentage of cell-free fetal DNA (cffDNA), an easily accessible source for determination of fetal disease status in risk families through non-invasive procedures. In case of monogenic heritable disease, background maternal cfDNA prohibits direct observation of the maternally inherited allele. Non-invasive prenatal diagnostics (NIPD) of monogenic diseases therefore relies on parental haplotyping and statistical assessment of inherited alleles from cffDNA, techniques currently unavailable for routine clinical practice. Here, we present monogenic NIPD (MG-NIPD), which requires a blood sample from both parents, for targeted locus amplification (TLA)-based phasing of heterozygous variants selectively at a gene of interest. Capture probes-based targeted sequencing of cfDNA from the pregnant mother and a tailored statistical analysis enables predicting fetal gene inheritance. MG-NIPD was validated for 18 pregnancies, focusing on CFTR, CYP21A2, and HBB. In all cases we could predict the inherited alleles with >98% confidence, even at relatively early stages (8 weeks) of pregnancy. This prediction and the accuracy of parental haplotyping was confirmed by sequencing of fetal material obtained by parallel invasive procedures. MG-NIPD is a robust method that requires standard instrumentation and can be implemented in any clinic to provide families carrying a severe monogenic disease with a prenatal diagnostic test based on a simple blood draw

Enquête : niveau de connaissance de la population au sujet du radon en Suisse

Une enquête a été réalisée en 1995, afin d’appréhender le niveau de connaissance des Suisses sur le thème du radon. En 2008, une deuxième enquête, basée sur une méthodologie similaire, a été menée par l’OFSP. La nouvelle étude a montré qu’environ 40 % de la population suisse a déjà entendu parler du radon, ce qui représente une augmentation de 8 % par rapport à l’enquête de 1995. La majorité des personnes interrogées savaient que le radon provoque le cancer du poumon, mais pensaient que le gaz induit aussi d’autres effets sur la santé, notamment la migraine et les affections dermatologiques. Par ailleurs, les personnes âgées, avec un niveau élevé de formation et propriétaires immobiliers connaissaient tendanciellement mieux la problématique du radon que le grand public. Les habitants des régions à risque élevé ont obtenus des résultats nettement meilleurs, ce qui démontre que les campagnes d’information dans ces régions ont porté leurs fruits. Par contre, un effort d’information supplémentaire est nécessaire dans les communes à risque léger et moyen, dans lesquelles la majeure partie de la population réside

Impact of ICT used within SMEs in Eldoret, Kenya.

A number of Small and Medium Enterprises (SMEs) in developing countries are slowly but steadily beginning to embrace the use of Information and Communication Technology (ICT). With such proliferation it is critical that the much anticipated positive impacts from such investments are realized. This has, however, not been true for many SMEs in developing countries, largely because a number of ICT solutions used within the SMEs do not adequately address their unique needs. As a result, many have ended up frustrated with their ICT investments. Our objective in this study was to build a snapshot on the impact of ICT used in SMEs in Eldoret, Kenya. Findings from this study reveal low positive impact of ICT on the SMEs. In the study, we identify factors that are responsible for the low impact of ICT on the SMEs and recommend actions that can be taken to ensure the adopted ICT brings positive change to the SMEs. Impact of ICT used within SMEs in Eldoret, Kenya - ResearchGate. Available from: http://www.researchgate.net/publication/272795296_Impact_of_ICT_used_within_SMEs_in_Eldoret_Kenya [accessed Oct 14, 2015]

Absorptive Capacity and Information Technology Adoption Strategies: A Study of SMEs in Kenya

Many small and medium enterprises (SMEs) in developing countries continue to be challenged by their information technology (IT) adoption process, which is often characterized by a number of deficiencies. The purpose of this study was to examine the role of absorptive capacity (AC) in SMEs’ performance, as well as establish the correlation between SMEs’ AC and their IT adoption process. The findings of this study, obtained by measuring different dimensions of AC using Jimenez-Barrionuevo, Garcia-Morales, and Molina’s scale of 18 items, suggest that AC plays a critical role in the performance of SMEs in Kenya and that SMEs with strong AC employed the use of more superior IT adoption processes than did their counterparts with low levels of AC. The researchers submit that, if exploited, AC has the potential to improve the IT adoption strategies of SMEs in Kenya and those of other developing countries that operate within similar environments

Information and communication technologies within small and medium enterprises in developing economies

With the realization of the benefits associated with the adoption of information and communication technologies (ICTs), many small and medium enterprises (SMEs) in developing economies are beginning to embrace the use of ICT. This process has, however, been marred with numerous challenges, characterizing the process as slow paced adoption and use of poor quality ICTs that are outdated, ineffective and inefficient. This is partly attributed to the fact that most developing economies are not well positioned to provide conducive environments for their SMEs to thrive, even in their efforts to embrace ICT. Notwithstanding the many challenges, SMEs in developing economies are slowly but steadily starting to embrace the use of ICTs. Therefore, the objective in this article is to review literature on ICT usage within SMEs in developing economies. The authors concluded that by strategically positioning their ICT, SMEs can tap into the enormous potential advantages offered by ICT to gain a competitive advantage. The authors further submit that SMEs can make use of their flexibility and relatively small size to their advantage, because these are perfect conditions for the diffusion and application of ICT