Brief overview on bio-based adhesives and sealants

Adhesives and sealants (AS) are materials with excellent properties, versatility, and simple curing mechanisms, being widely used in different areas ranging from the construction to the medical sectors. Due to the fast-growing demand for petroleum-based products and the consequent negative environmental impact, there is an increasing need to develop novel and more sustainable sources to obtain raw materials (monomers). This reality is particularly relevant for AS industries, which are generally dependent on non-sustainable fossil raw materials. In this respect, biopolymers, such as cellulose, starch, lignin, or proteins, emerge as important alternatives. Nevertheless, substantial improvements and developments are still required in order to simplify the synthetic routes, as well as to improve the biopolymer stability and performance of these new bio-based AS formulations. This environmentally friendly strategy will hopefully lead to the future partial or even total replacement of non-renewable petroleum-based feedstock. In this brief overview, the general features of typical AS are reviewed and critically discussed regarding their drawbacks and advantages. Moreover, the challenges faced by novel and more ecological alternatives, in particular lignocellulose-based solutions, are highlighted.Funding Agency Portuguese Foundation for Science and Technology PTDC/AGR-TEC/4814/2014; PTDC/ASP-SIL/30619/2017; IF/01005/2014.info:eu-repo/semantics/publishedVersio

Susceptibility characterization of beam pipe radiated noise for the PXD detector in Belle II experiment

The new Pixel Vertex Detector (PXD) used in the upgrade of the high energy physics experiment Belle II is based on the DEPFET technology. Since the PXD is 2 mm far from the beam pipe, the effects of radiated interferences may be taken into account. Though the EM wave associated to the beam is very well confined (skin depth), the beam pipe is grounded to the accelerator and it may have noise currents on its external face due to pumps, auxiliary electronics, power converters, etc. which may produce radiated noise (H field). This analysis is part of the EMC approach that covers the analysis of the emissions and immunity characteristics, as well as the coupling phenomena and grounding issues to define the susceptibility levels required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics

Maximal multihomogeneity of algebraic hypersurface singularities

From the degree zero part of logarithmic vector fields along an algebraic hypersurface singularity we indentify the maximal multihomogeneity of a defining equation in form of a maximal algebraic torus in the embedded automorphism group. We show that all such maximal tori are conjugate and in one-to-one correspondence to maxmimal tori in the degree zero jet of the embedded automorphism group. The result is motivated by Kyoji Saito's characterization of quasihomogeneity for isolated hypersurface singularities and extends its formal version and a result of Hauser and Mueller.Comment: 5 page

Induced pluripotent stem cells from hair follicles as a cellular model for neurodevelopmental disorders

AbstractDisease-specific induced pluripotent stem cells (iPSC) allow unprecedented experimental platforms for basic research as well as high-throughput screening. This may be particularly relevant for neuropsychiatric disorders, in which the affected neuronal cells are not accessible. Keratinocytes isolated from hair follicles are an ideal source of patients' cells for reprogramming, due to their non-invasive accessibility and their common neuroectodermal origin with neurons, which can be important for potential epigenetic memory. From a small number of plucked human hair follicles obtained from two healthy donors we reprogrammed keratinocytes to pluripotent iPSC. We further differentiated these hair follicle-derived iPSC to neural progenitors, forebrain neurons and functional dopaminergic neurons.This study shows that human hair follicle-derived iPSC can be differentiated into various neural lineages, suggesting this experimental system as a promising in vitro model to study normal and pathological neural developments, avoiding the invasiveness of commonly used skin biopsies

The Hubbard Model at Infinite Dimensions: Thermodynamic and Transport Properties

We present results on thermodynamic quantities, resistivity and optical conductivity for the Hubbard model on a simple hypercubic lattice in infinite dimensions. Our results for the paramagnetic phase display the features expected from an intuitive analysis of the one-particle spectra and substantiate the similarity of the physics of the Hubbard model to those of heavy fermion systems. The calculations were performed using an approximate solution to the single-impurity Anderson model, which is the key quantity entering the solution of the Hubbard model in this limit. To establish the quality of this approximation we compare its results, together with those obtained from two other widely used methods, to essentially exact quantum Monte Carlo results.Comment: 29 pages, 16 figure

Cobalt-katalysierte enantioselektive Hydrierung von dreifach substituierten carbocyclischen Olefinen:Zugang zu chiralen cyclischen Amiden

Die enantioselektive Hydrierung von cyclischen Enamiden wurde mit einem Cobalt-Bisphosphin-Katalysator erreicht. Die Reduktion verschiedenster dreifach substituierter carbocyclischen Enamide zu den entsprechenden gesättigten Amiden erfolgte mit hoher Aktivität und ausgezeichneter Enantioselektivität (bis zu 99 %) unter Verwendung des Systems CoCl2/(S,S)-Ph-BPE. Die Methode lässt sich auf die Synthese chiraler Amine durch eine basische Hydrolyse der Hydrierungsprodukte ausweiten. Erste mechanistische Untersuchungen deuten auf die Anwesenheit einer high-spin Cobalt(II)-Spezie im katalytischen Cyclus hin. Wir postulieren die Hydrierung der Kohlenstoff-Kohlenstoff-Doppelbindung über einen Sigma-Bindungs-Metathese-Weg

Sum rules and dualities for generalized parton distributions: is there a holographic principle?

To leading order approximation, the physical content of generalized parton distributions (GPDs) that is accessible in deep virtual electroproduction of photons or mesons is contained in their value on the cross-over trajectory. This trajectory separates the t-channel and s-channel dominated GPD regions. The underlying Lorentz covariance implies correspondence between these two regions through their relation to GPDs on the cross-over trajectory. This point of view leads to a family of GPD sum rules which are a quark analogue of finite energy sum rules and it guides us to a new phenomenological GPD concept. As an example, we discuss the constraints from the JLab/Hall A data on the dominant u-quark GPD H. The question arises whether GPDs are governed by some kind of holographic principle.Comment: 45 pages, 4 figures, Sect. 2 reorganized for clarity. Typos in Eq. (20) corrected. 4 new refs. Matches published versio

Response shift after cognitive behavioral therapy targeting severe fatigue: explorative analysis of three randomized controlled trials

Health and self-regulationMultivariate analysis of psychological dat

Spectral properties of the dimerized and frustrated S=1/2S=1/2 chain

Spectral densities are calculated for the dimerized and frustrated S=1/2 chain using the method of continuous unitary transformations (CUTs). The transformation to an effective triplon model is realized in a perturbative fashion up to high orders about the limit of isolated dimers. An efficient description in terms of triplons (elementary triplets) is possible: a detailed analysis of the spectral densities is provided for strong and intermediate dimerization including the influence of frustration. Precise predictions are made for inelastic neutron scattering experiments probing the S=1 sector and for optical experiments (Raman scattering, infrared absorption) probing the S=0 sector. Bound states and resonances influence the important continua strongly. The comparison with the field theoretic results reveals that the sine-Gordon model describes the low-energy features for strong to intermediate dimerization only at critical frustration.Comment: 21 page