Boosting the photocatalytic performance of PAN-TiO2 nanostructured membranes by mechanosynthesis

Mechano-synthesized TiO2 nanoparticles have been explored for their activity towards gas-phase photodegradation of methanol. The effect of milling time over the photoactivity in terms of degradation efficiency has been studied. Titania nanopowders milled for 2 and 8 h were compared with the commercial unmilled catalyst and it has been established that there is a significant impact of milling time over the activity of the catalyst. The current study unveiled that the 2 hr milled sample performs far superior than the pristine catalyst with several order higher kinetics, while with further increase in the milling time the activity drastically reduces. Such behavior has been attributed to higher absorption of radiation as well as increased photo-carrier generation in the milled samples

Observation of spontaneous self-channelling of light in air below the collapse threshold

We report the observation of the self-guided propagation of 120 fs, 0.56 mJ infrared radiation in air for distances greater than one meter. In contrast to the known case of filamentation, in the present experiment the laser power is lower than the collapse threshold. Therefore the counter balance between Kerr self focussing and ionization induced defocussing as the stabilizing mechanism is ruled out. Instead, we find evidences of a process in which the transversal beam distribution reshapes into a form similar to a Townes soliton. We include numerical support for this conclusion

Three-dimensional numerical simulation of 1GeV/Nucleon U92+ impact against atomic hydrogen

The impact of 1GeV/Nucleon U92+ projectiles against atomic hydrogen is studied by direct numerical resolution of the time-dependent wave equation for the atomic electron on a three-dimensional Cartesian lattice. We employ the fully relativistic expressions to describe the electromagnetic fields created by the incident ion. The wave equation for the atom interacting with the projectile is carefully derived from the time-dependent Dirac equation in order to retain all the relevant terms.Comment: 12 pages and 7 figures included in the tex

Multimorbidity patterns with K-means nonhierarchical cluster analysis

This is the final version. Available on open access from BMC via the DOI in this recordAvailability of data and materials: The datasets are not available because researchers have signed an agreement with the Information System for the Development of Research in Primary Care (SIDIAP) concerning confidentiality and security of the dataset that forbids providing data to third parties. This organization is subject to periodic audits to ensure the validity and quality of the data.BACKGROUND: The purpose of this study was to ascertain multimorbidity patterns using a non-hierarchical cluster analysis in adult primary patients with multimorbidity attended in primary care centers in Catalonia. METHODS: Cross-sectional study using electronic health records from 523,656 patients, aged 45-64 years in 274 primary health care teams in 2010 in Catalonia, Spain. Data were provided by the Information System for the Development of Research in Primary Care (SIDIAP), a population database. Diagnoses were extracted using 241 blocks of diseases (International Classification of Diseases, version 10). Multimorbidity patterns were identified using two steps: 1) multiple correspondence analysis and 2) k-means clustering. Analysis was stratified by sex. RESULTS: The 408,994 patients who met multimorbidity criteria were included in the analysis (mean age, 54.2 years [Standard deviation, SD: 5.8], 53.3% women). Six multimorbidity patterns were obtained for each sex; the three most prevalent included 68% of the women and 66% of the men, respectively. The top cluster included coincident diseases in both men and women: Metabolic disorders, Hypertensive diseases, Mental and behavioural disorders due to psychoactive substance use, Other dorsopathies, and Other soft tissue disorders. CONCLUSION: Non-hierarchical cluster analysis identified multimorbidity patterns consistent with clinical practice, identifying phenotypic subgroups of patients.The project has been funded by the Instituto de Salud Carlos III of the Ministry of Economy and Competitiveness (Spain) through the Network for Prevention and Health Promotion in Primary Health Care (redIAPP, RD12/0005), by a grant for research projects on health from ISCiii (PI12/00427) and co-financed with European Union ERDF funds). Jose M. Valderas was supported by the National Institute for Health Research Clinician Scientist Award NIHR/CS/010/024

Transferring orbital and spin angular momenta of light to atoms

Light beams carrying orbital angular momentum, such as Laguerre-Gaussian beams, give rise to the violation of the standard dipolar selection rules during the interaction with matter yielding, in general, an exchange of angular momentum larger than hbar per absorbed photon. By means of ab initio 3D numerical simulations, we investigate in detail the interaction of a hydrogen atom with intense Gaussian and Laguerre-Gaussian light pulses. We analyze the dependence of the angular momentum exchange with the polarization, the orbital angular momentum, and the carrier-envelope phase of light, as well as with the relative position between the atom and the light vortex. In addition, a quantum-trajectory approach based on the de Broglie-Bohm formulation of quantum mechanics is used to gain physical insight into the absorption of angular momentum by the hydrogen atom