Scaling in second order electron correlation calculations of potential energy curves and spectroscopic constants

The determination of potential energy curves and spectroscopic constants using the method of scaling in second order electron correlation calculations is investigated. An application to the ground state of the fluorine molecule is described using full fourth order many-body perturbation theory within two basis sets.     

Structural characterization of radiation‐grafted block copolymer films,using SANS technique

We report small‐angle neutron scattering studies of grafted copolymer films of perfluorinated poly(ethylene propylene), FEP, base polymer and polystyrene, PS, grafted blocks. The films show highly anisotropic scattering patterns, revealing nematic‐like ordering of the crystalline domain structure as a consequence of the processing conditions. Upon grafting, the styrene swells the amorphous domains in the copolymer formation. For styrene content beyond roughly 15%, the amorphous regimes increase on the cost of crystalline domains. To stabilize the rather well‐defined domain structure already given by the original FEP base material, the samples need to be cross‐linked. Without cross‐linking, the nanometer length scale domains vanish, and some large scale structure takes over, likely driven by the immiscibility between FEP and PS. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1660–1668, 2008     

Stereospecific synthesis of an α-mannosidase inhibitor relatedto swainsonine

A stereospecific synthesis of pyrrolidine $\text{2}$, an analog of swainsonine and an inhibitor of lysosomal α-D-mannosidase, is described.     

A retro-Diels-Alder reaction to uncover maleimide-modified surfaces on monolayer-protected nanoparticles for reversible covalent assembly

Maleimide-modified monolayer-protected gold nanoparticles (MPGN) are prepared from the protected furan-maleimide via the thermally reversible Diels-Adler reaction when required. These maleimide-MPGNs serve as a general platform allowing for a Diels-Alder reaction with furan-modified MPN to prepare larger 3D networks reversibly. [reaction: see text]     

Fourth-order diagrammatic MB-RSPT calculations of the interaction energy between two helium atoms

The efficiency of the MB-RSPT in the calculations of the correlation contributions to the interaction energies was investigated, using He₂ as a model Van der Waals system. The attention has been focused on the convergency of the perturbation expansion in the calculations of the interaction energy and on the analysis of the fourth-order terms of MB-RSPT. The rôle of the renormalization term in the correct long-range behaviour of the interaction potential has been emphasized.     

Correction of the influence of baseline artefacts and electrode polarisation on dielectric spectra

The deconvolution of biological dielectric spectra can be difficult enough with artefact-free spectra but is more problematic when machine baseline artefacts and electrode polarisation are present as well. In addition, these two sources of anomalies can be responsible for significant interference with dielectric biomass measurements made using one- or two-spot frequencies. The aim of this paper is to develop mathematical models of baseline artefacts and electrode polarisation which can be used to remove these anomalies from dielectric spectra in a way that can be easily implemented on-line and in real-time on the Biomass Monitor (BM). We show that both artefacts can be successfully removed in solutions of organic and inorganic ions; in animal cell and microbial culture media; and in yeast suspensions of varying biomass. The high quality of the compensations achieved were independent of whether gold and platinum electrodes were used; the electrode geometry; electrode fouling; current density; the type of BM; and of whether electrolytic cleaning pulses had been applied. In addition, the calibration experiments required could be done off-line using a simple aqueous KCl dilution series with the calibration constants being automatically calculated by a computer without the need for user intervention. The calibration values remained valid for a minimum of 3 months for the baseline model and indefinitely for the electrode polarisation one. Importantly, application of baseline correction prior to polarisation correction allowed the latter's application to the whole conductance range of the BM. These techniques are therefore exceptionally convenient to use under practical conditions.     

Relativistic calculations of AuSi+ and AuSi−

Theoretical calculations of the electronic structure of the ground state and a series of excited states of the AuSi⁺ and AuSi⁻ molecules are presented. The calculations were carried out with the spin-free relativistic infinite-order two-component (IOTC) method and high-level complete active space self-consistent field/complete active space perturbation theory correlated methods. The spin-orbit (SO) coupling was introduced via the restricted active space state interaction method with the use of the atomic mean-field SO integrals. The work presents the spectroscopic parameters of calculated states and full potential energy curves of the ionic AuSi⁺ and AuSi⁻ structures for the first time. Electrostatic potential maps projected on the electron density surface illustrate the significant relativistic effects on going from nonrelativistic to scalar relativistic treatments.     

Behavioral patterns of older-adults in assisted living

In this paper, we examine at-home activity rhythms and present a dozen of behavioral patterns obtained from an activity monitoring pilot study of 22 residents in an assisted living setting with four case studies. Established behavioral patterns have been captured using custom software based on a statistical predictive algorithm that models circadian activity rhythms (CARs) and their deviations. The CAR was statistically estimated based on the average amount of time a resident spent in each room within their assisted living apartment, and also on the activity level given by the average number of motion events per room. A validated in-home monitoring system (IMS) recorded the monitored resident's movement data and established the occupancy period and activity level for each room. Using these data, residents' circadian behaviors were extracted, deviations indicating anomalies were detected, and the latter were correlated to activity reports generated by the IMS as well as notes of the facility's professional caregivers on the monitored residents. The system could be used to detect deviations in activity patterns and to warn caregivers of such deviations, which could reflect changes in health status, thus providing caregivers with the opportunity to apply standard of care diagnostics and to intervene in a timely manner.