Harmonic oscillator model for current- and field-driven magnetic vortices

In experiments the distinction between spin-torque and Oersted-field driven magnetization dynamics is still an open problem. Here, the gyroscopic motion of current- and field-driven magnetic vortices in small thin-film elements is investigated by analytical calculations and by numerical simulations. It is found that for small harmonic excitations the vortex core performs an elliptical rotation around its equilibrium position. The global phase of the rotation and the ratio between the semi-axes are determined by the frequency and the amplitude of the Oersted field and the spin torque

Current-Driven Domain-Wall Dynamics in Curved Ferromagnetic Nanowires

The current-induced motion of a domain wall in a semicircle nanowire with applied Zeeman field is investigated. Starting from a micromagnetic model we derive an analytical solution which characterizes the domain-wall motion as a harmonic oscillation. This solution relates the micromagnetic material parameters with the dynamical characteristics of a harmonic oscillator, i.e., domain-wall mass, resonance frequency, damping constant, and force acting on the wall. For wires with strong curvature the dipole moment of the wall as well as its geometry influence the eigenmodes of the oscillator. Based on these results we suggest experiments for the determination of material parameters which otherwise are difficult to access. Numerical calculations confirm our analytical solution and show its limitations

Experimental salt marsh islands: a model system for novel metacommunity experiments

Shallow tidal coasts are characterised by shifting tidal flats and emerging or eroding islands above the high tide line. Salt marsh vegetation colonising new habitats distant from existing marshes are an ideal model to investigate metacommunity theory. We installed a set of 12 experimental salt marsh islands made from metal cages on a tidal flat in the German Wadden Sea to study the assembly of salt marsh communities in a metacommunity context. Experimental plots at the same elevation were established within the adjacent salt marsh on the island of Spiekeroog. For both, experimental islands and salt marsh enclosed plots, the same three elevational levels were realised while creating bare patches open for colonisation and vegetated patches with a defined transplanted community. One year into the experiment, the bare islands were colonised by plant species with high fecundity although with a lower frequency compared to the salt marsh enclosed bare plots. Initial plant community variations due to species sorting along the inundation gradient were evident in the transplanted vegetation. Competitive exclusion was not observed and is only expected to unfold in the coming years. Our study highlights that spatially and temporally explicit metacommunity dynamics should be considered in salt marsh plant community assembly and disassembly

Asymetric Triblock Copolymer Nanocarriers for Controlled Localization and pH-Sensitive Release of Proteins

Designing nanocarriers to release proteins under specific conditions is required to improve therapeutic approaches, especially in treating cancer and protein deficiency diseases. We present here supramolecular assemblies based on asymmetric poly(ethylene glycol)-b-poly(methylcaprolactone)-b-poly(2-(N,Ndiethylamino)ethyl methacrylate) (PEG-b-PMCL-b-PDMAEMA) copolymers for controlled localization and pH-sensitive release of proteins. Copolymers self-assembled in soft nanoparticles with a core domain formed by PMCL, and a hydrophilic domain based on PEG mainly embedded inside, and the branched PDMAEMA exposed at the particle surface. We selected as model proteins to be attached to the nanoparticles bovine serum albumin (BSA) and acid sphingomyelinase (ASM), the latter being an ideal candidate for protein replacement therapy. The hydrophilic/hydrophobic ratio, nanoparticle size, and the nature of biomolecules are key factors for modulating protein localization and attachment efficiency. The predominant outer shell of PDMAEMA allows efficient pH-triggered release of BSA and ASM, and in acidic conditions >70% of the bound proteins were released. Uptake of protein-attached nanoparticles by HELA cells, together with low toxicity and pH-responsive release, supports such protein-bound nanoparticles as efficient stimuli-responsive candidates for protein therapy

Primary Hemiarthroplasty for Proximal Humeral Fractures in the Elderly: Long-Term Functional Outcome and Social Implications

Background:: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term functional outcome is often disappointing. However, little is known about social implications particularly in the elderly. Methods:: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function, radiological outcome and social implications were evaluated. Results:: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70-93 years). Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25-80 months), 22 (29%) died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination. Median Constant-Murley score was 41 points (range 17-77 points). Long-term results concerning pain were satisfying. The Oxford shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash their whole body by themselves. Conclusion:: Most patients managed their daily life independently despite poor shoulder functio

Integración de redacciones en Austria, España y Alemania : modelos de convergencia de medios

El presente artículo trata sobre el trabajo de los periodistas en las redacciones que elaboran contenidos para múltiples medios: prensa, radio, televisión, Internet y otros. El estudio explora los procesos de cambio en las prácticas periodísticas y el flujo de trabajo en las redacciones de seis empresas de comunicación en tres países: Österreich y Der Standard en Austria; La Verdad Multimedia y El Mundo en España; y los grupos Die Welt/Morgenpost y Hessische/Niedersächsische Allgemeine en Alemania. Los autores entrevistaron a profesiona-les y llevaron a cabo un período de observación en cada redacción. Se elaboró una matriz de descriptores de la convergencia que abarcan el enfoque del proyecto, la gestión redaccional, la práctica periodística y la organización del trabajo. Los resultados plantean la existencia de tres modelos diferentes de convergencia de redacciones: el de integración plena, el de colaboración entre redacciones y el de coordinación de soportes aislados, cada uno con sus propios rasgos configuradores. Aunque ninguno de los modelos propuestos existe de forma pura y ninguna de las compañías analizadas cumple totalmente los requisitos de cada uno, buena parte de las experiencias de integración marcan distintos grados de desarrollo empresarial y polivalencia periodística.This article addresses the work of journalists in newsrooms producing content for multiple media: print, radio, television, the internet and others. Specifically, the study explores change in journalistic practice and workflow in the newsrooms of six European media companies: Austria's Österreich and Der Standard; Spain's La Verdad Multimedia and El Mundo; and Germany's Die Welt/Morgenpost Group and Hessische/Niedersächsische Allgemeine. Researchers interviewed reporters and news directors and observed newsroom practices. Aspects of project scope, newsroom management, journalistic practices and work organization were analysed by using a matrix of convergence descriptors. The results suggest the emergence of three different models of newsroom convergence: full integration, cross-media collaboration and coordination of isolated platforms, with each of them having a different production system, newsroom organization and degree of journalists' multi-skilling. Although none of the cases studied fits completely into any of those models, and they might not be regarded as «pure models», they still can be useful approaches to analyze the development of any particular media company

Targeting αvβ3 and αvβ5 integrins inhibits pulmonary metastasis in an intratibial xenograft osteosarcoma mouse model

Osteosarcoma is an aggressive bone cancer that has a high propensity for metastasis to the lungs. Patients with metastatic disease face a very poor prognosis. Therefore, novel therapeutics, efficiently suppressing the metastatic process, are urgently needed. Integrins play a pivotal role in tumor cell adhesion, motility and metastasis. Here, we evaluated αvβ3 and αvβ5 integrin inhibition with cilengitide as a novel metastasis-suppressive therapeutic approach in osteosarcoma. Immunohistochemical analysis of αvβ3 and αvβ5 integrins expression in a tissue microarray of tumor specimens collected from osteosarcoma patients revealed that αvβ5 integrin is mainly found on tumor cells, whereas αvβ3 is predominantly expressed by stromal cells. In vitro functional assays demonstrated that cilengitide dose-dependently inhibited de novo adhesion, provoked detachment and inhibited migration of osteosarcoma cell lines. Cilengitide induced a decline in cell viability, blocked the cell cycle in the G1 phase and caused anoikis by activation of the Hippo pathway. In a xenograft orthotopic mouse model cilengitide minimally affected intratibial primary tumor growth but, importantly, suppressed pulmonary metastasis. The data demonstrate that targeting αvβ3 and αvβ5 integrins in osteosarcoma should be considered as a novel therapeutic option for patients with metastatic disease

Dsg1 and Dsg3 Composition of Desmosomes Across Human Epidermis and Alterations in Pemphigus Vulgaris Patient Skin

Desmosomes are important epidermal adhesion units and signalling hubs, which play an important role in pemphigus pathogenesis. Different expression patterns of the pemphigus autoantigens desmoglein (Dsg)1 and Dsg3 across different epidermal layers have been demonstrated. However, little is known about changes in desmosome composition in different epidermal layers or in patient skin. The aim of this study was thus to characterize desmosome composition in healthy and pemphigus skin using super-resolution microscopy. An increasing Dsg1/Dsg3 ratio from lower basal (BL) to uppermost granular layer (GL) was observed. Within BL desmosomes, Dsg1 and Dsg3 were more homogeneously distributed whereas superficial desmosomes mostly comprised one of the two molecules or domains containing either one but not both. Extradesmosomal, desmoplakin (Dp)-independent, co-localization of Dsg3 with plakoglobin (Pg) was found mostly in BL and extradesmosomal Dsg1 co-localization with Pg in all layers. In contrast, in the spinous layer (SL) most Dsg1 and Dsg3 staining was confined to desmosomes, as revealed by the co-localization with Dp. In pemphigus patient skin, Dsg1 and Dsg3 immunostaining was altered especially along blister edges. The number of desmosomes in patient skin was reduced significantly in basal and spinous layer keratinocytes with only few split desmosomes found. In addition, Dsg1-Pg co-localization at the apical BL and Dsg3-Pg co-localization in SL were significantly reduced in patients, suggesting that that extradesmosomal Dsg molecules were affected. These results support the hypothesis that pemphigus is a desmosome assembly disease and may help to explain histopathologic differences between pemphigus phenotypes

AtPTR4 and AtPTR6 are differentially expressed, tonoplast-localized members of the peptide transporter/nitrate transporter 1 (PTR/NRT1) family

Members of the peptide transporter/nitrate transporter 1 (PTR/NRT1) family in plants transport a variety of substrates like nitrate, di- and tripepetides, auxin and carboxylates. We isolated two members of this family from Arabidopsis, AtPTR4 and AtPTR6, which are highly homologous to the characterized di- and tripeptide transporters AtPTR1, AtPTR2 and AtPTR5. All known substrates of members of the PTR/NRT1 family were tested using heterologous expression in Saccharomyces cerevisiae mutants and oocytes of Xenopus laevis, but none could be identified as substrate of AtPTR4 or AtPTR6. AtPTR4 and AtPTR6 show distinct expression patterns, while AtPTR4 is expressed in the vasculature of the plants, AtPTR6 is highly expressed in pollen and during senescence. Phylogenetic analyses revealed that AtPTR2, 4 and 6 belong to one clade of subgoup II, whereas AtPTR1 and 5 are found in a second clade. Like AtPTR2, AtPTR4-GFP and AtPTR6-GFP fusion proteins are localized at the tonoplast. Vacuolar localization was corroborated by co-localization of AtPTR2-YFP with the tonoplast marker protein GFP-AtTIP2;1 and AtTIP1;1-GFP. This indicates that the two clades reflect different intracellular localization at the tonoplast (AtPTR2, 4, 6) and plasma membrane (AtPTR1, 5), respectivel