Epitaxial growth of ultrathin palladium films on Re{0001}

Ultrathin bimetallic layers create unusual magnetic and surface chemical effects through the modification of electronic structure brought on by low dimensionality, polymorphism, reduced screening, and epitaxial strain. Previous studies have related valence and core-level shifts to surface reactivity through the d-band model of Hammer and Nørskov, and in heteroepitaxial films this band position is determined by competing effects of coordination, strain, and hybridization of substrate and overlayer states. In this study we employ the epitaxially matched Pd on Re{0001} system to grow films with no lateral strain. We use a recent advancement in low-energy electron diffraction to expand the data range sufficiently for a reliable determination of the growth sequence and out-of-plane surface relaxation as a function of film thickness. The results are supported by scanning tunneling microscopy and X-ray photoemission spectroscopy, which show that the growth is layer-by-layer with significant core-level shifts due to changes in film structure, morphology, and bonding

Fatty acid composition of milk of refugee Karen and urban Korean mothers. Is the level of DHA in breast milk of Western women compromised by high intake of saturated fat and linoleic acid?

Background: Lower proportions of docosahexaenoic acid (DHA) and total n-3 metabolites have been reported in breast milk of European, Australian and North American women compared with milk of mothers from non-Western countries. This difference is not always explained by intakes of marine products. Objective: We investigated the possibility that the relative composition of DHA and total n-3 metabolites in breast milk of non-Western mothers with low fat intakes is higher than the levels commonly reported in their Western counterparts. Subjects: Mature milk of refugee Karen women from two different camps in Thailand (n = 26 and n = 53), and transition milk from urban Korean mothers (n = 12) in Seoul was collected. In common with their respective community, the mothers have low fat intake, which is predominately of plant origin. Results: The percentage levels of DHA and n-3 metabolites in the milk of the Karen mothers were 0.52 ± 0.14 and 0.85 ± 0.24 (camp 1) and 0.54 ± 0.22 and 0.92 ± 0.42 (camp 2). In the Korean milk, DHA was 0.96 ± 0.21 and total n-3 metabolites 1.51 ± 0.3. Conclusion: We postulate that the levels of DHA and total n-3 metabolites may be compromised in breast milk of mothers on the Western high fat diet. This calls into question the use of DHA composition of such milk as a reference for the formulation of milk designed, for infant feed or, to test the function of DHA in neuro-visual development

Using quantitative single molecule localization microscopy to optimize multivalent HER2-targeting ligands

IntroductionThe progression-free survival of patients with HER2-positive metastatic breast cancer is significantly extended by a combination of two monoclonal antibodies, trastuzumab and pertuzumab, which target independent epitopes of the extracellular domain of HER2. The improved efficacy of the combination over individual antibody therapies targeting HER2 is still being investigated, and several molecular mechanisms may be in play: the combination downregulates HER2, improves antibody-dependent cell mediated cytotoxicity, and/or affects the organization of surface-expressed antigens, which may attenuate downstream signaling.MethodsBy combining protein engineering and quantitative single molecule localization microscopy (qSMLM), here we both assessed and optimized clustering of HER2 in cultured breast cancer cells.ResultsWe detected marked changes to the cellular membrane organization of HER2 when cells were treated with therapeutic antibodies. When we compared untreated samples to four treatment scenarios, we observed the following HER2 membrane features: (1) the monovalent Fab domain of trastuzumab did not significantly affect HER2 clustering; (2) individual therapy with either trastuzumab or (3) pertuzumab produced significantly higher levels of HER2 clustering; (4) a combination of trastuzumab plus pertuzumab produced the highest level of HER2 clustering. To further enhance this last effect, we created multivalent ligands using meditope technology. Treatment with a tetravalent meditope ligand combined with meditope-enabled trastuzumab resulted in pronounced HER2 clustering. Moreover, compared to pertuzumab plus trastuzumab, at early time points this meditope-based combination was more effective at inhibiting epidermal growth factor (EGF) dependent activation of several downstream protein kinases.DiscussionCollectively, mAbs and multivalent ligands can efficiently alter the organization and activation of the HER2 receptors. We expect this approach could be used in the future to develop new therapeutics

Similarità e concorrenza tra imprese : verso una prospettiva firm-centered

The concept of similarity among businesses has always been one of the most important logical categories in the assessment of competition, both in the industrial economics and in managerial analysis. The paper highlights, in particular, how strategic groupings, which initially focused on the similarity of firms\u2019 "structural" elements and strategies, have undergone a fundamental change. This is evident in the different conceptions of similarity assumed over time, in their different functions with respect to rivalry, and finally, in the fact that the perspective may be subjective or objective, i.e. conditioned by supply or demand. Some of the most important stages the paper underlines are, above all, the results from the resource based view, the contributions of the cognitive approach, the network developments in industry groups, and the analysis of competition from the point of view of demand. However, the progressive contamination of the model negates the possibility of truly appreciating rivalry among firms on the basis of generic similarity, while underlining, on the other hand, the importance of considering the uniqueness of individual competitive relation

Similarità e concorrenza tra imprese: verso una prospettiva firm-centered

similarità tra imprese come criterio di identificazione dei concorrent

Autorità e potere nei Paesi musulmani : concetti e pratiche

Gli eventi riportati dalle cronache internazionali evidenziano il fermento culturale, sociale e politico che esiste oggi nei Paesi a maggioranza musulmana. Questi accadimenti nascono da tensioni politiche e socio-economiche e da dialettiche culturali che, da un lato, hanno delle specificit\ue0 nazionali, e, dall'altro, una natura precipua ma transnazionale. Essa si pu\uf2 spiegare attraverso il consenso che larghi strati delle popolazioni musulmane accordano a figure di autorit\ue0, istituzioni sociali o sistemi normativi e concettuali tradizionali che sono sopravvissuti nel corso dei secoli, adattandosi e rimodellandosi in base alle mutate condizioni storiche. Dalla coscienza della complessit\ue0 di questi apporti prende le mosse questo libro, che vuole mettere a fuoco la pluralit\ue0 che sostanzia il concetto stesso di \uabautorit\ue0\ubb. Le direttrici sottese dalla riflessione sono, quindi, necessariamente due: quella dell'eterogeneit\ue0, sia essa intesa in senso cronologico o geografico; e quella della continuit\ue0, che ha permesso la persistenza di categorie di pensiero, istituzioni e strutture sociali che hanno dato forme per certi versi simili alle civilt\ue0 del Vicino e Medio Oriente, al subcontinente indiano, ma anche, al di l\ue0 di queste, a parte dell'Africa subsahariana e alle isole del sudest asiatico

Aspetti dell'autorità nei Paesi musulmani: riflessioni e prospettive

This chapter outlines the scope of the volume, discussing key concepts around the concept of authority and power in different historical and regional contexts

Letture guidate in arabo

Letture guidate in arabo è un manuale che si rivolge agli studenti universitari di lingua e cultura araba, ai quali propone testi autentici che potranno accompagnare l’intero percorso quinquennale. Nello specifi co il volume è diviso in tre sezioni: “per cominciare” contiene testi brevi e attività graduate, in forma di moduli, proverbi e storie brevi, adatte agli studenti che stanno aff rontando i primi rudimenti della lingua; “letteratura” off re brani di letteratura sia classica che moderna, anche in dialetto, con un assaggio di poesia in metrica; “testi specialistici” aff ronta vari generi testuali quali abstract, discorsi uffi ciali, rifl essioni politiche o linguistiche e un’omelia del venerdì. Ogni testo è corredato da attività ed esercizi di comprensione, analisi e produzione