Size quantization effects in InAs self-assembled quantum dots

3 páginas, 3 figuras. PACS: 73.21.-b; 78.55.Cr; 78.66.Fd; 72.40.+w; 68.35.Ct; 73.40.KpWe study size quantization effects in InAs self-assembled quantum dots (QDs) that are embedded in GaAs. Using capacitance, photoluminescence and photovoltage spectroscopy, we correlate the measured quantized level energies with the quantum dot sizes and densities obtained from transmission electron microscopy. With increasing dot size, we observe a strong redshift of the QD features in all our data. In the capacitance spectra, a band gap renormalization of the two-dimensional wetting layer system appears when the first excited QD state crosses the wetting layer ground state. The relative size dependence and absolute energetic position of the QD transitions determined with photoluminescence provide some information about the influence of lateral confinement and height of the QD.This work was supported by QUEST, a NSF science and technology center (Grant No. DMR91-20007), the Alexander von Humboldt Foundation (KHS), and the Brazilian agency CNPq (GMR).Peer reviewe

Media representation of regulated incivilities: Relevant actors, problems, solutions and the role played by experts in the Flemish press

This article analyses the representations of regulated nuisance in a section of Flemish newspapers over time. It identifies the groups of people who have been successful in conveying messages in and through Flemish press news, and explores the way they have represented problems of, and suggested solutions to, regulated incivilities over the years. Furthermore, against the backdrop of newsmaking criminology, it considers whether and how crime and justice experts have contributed to shaping the Flemish media discourse on regulated incivilities over time. Overall the analysis of press news has found that the press, by giving coverage to the voices of local institutional actors, has promoted the criminalization of nuisance and, especially, of physical incivilities. The views of criminological experts, by contrast, have remained marginal. The article concludes by suggesting how such findings present a new set of empirical and conceptual challenges for newsmaking criminology, and more generally, for public criminology

Introduction: Knowledge, Power, and the “Settler Colonial Turn” in Palestine Studies

This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordThis special issue presents essays on the topic of settler colonialism in Palestine, covering conceptual and empirical, historical and contemporary, as well as literary, legal and political aspects of the debate. All essays examine the validity and applicability of the settler colonial paradigm to the context of Palestine (West Bank, Gaza Strip, East Jerusalem, and the 1948 territories). They approach this paradigm as a powerful means to challenge and disarticulate established historiographies and narratives, and, as such, engage with settler colonialism as a structure (Wolfe 1999, 2006), but also with the various forms of resistance and decolonization that aim at undoing this structure

Culturally informed resilience in conflict settings: A literature review of Sumud in the occupied Palestinian territories

Investigating culturally specific views and experiences of trauma and resilience can offer new insights that can aid distress management, meaning making, coping and resilience in adverse conditions, and inform emergency and disaster responses. Sumud is a Palestinian cultural construct and component of resilience in the occupied Palestinian territories (oPt). Sumud in Arabic refers to steadfastness or perseverance. This literature review focuses on research studies on Sumud in the oPt, with particular attention on the meaning and manifestations of Sumud, the role of non-violent resistance, and how Sumud and non-violent resistance informs resilience and coping in the context of a military occupation, protracted political conflict, and chronic adversity. The peer-reviewed literature was surveyed using the PubMed and PsycINFO databases. The findings indicate how Sumud is a central component of resilience and provides a meta-cognitive framework which Palestinians use to interpret, cope and respond to ongoing injustice and traumatic experiences, engendering a sense of purpose and meaning. It is both a value and an action that manifests via individual and collective action to protect family and community survival, wellbeing, dignity, Palestinian identity and culture, and a determination to remain on the land. The implications of this study and the relevance of the findings to mental health and disaster relief are considered

Adaptive Coping During Protracted Political Conflict, War and Military Blockade in Gaza

Identifying culturally-relevant concepts and coping mechanisms can help protect civilian wellbeing. This study explores how seven professional Palestinian university graduates in the Gaza Strip (occupied Palestinian territories) cope with war, military occupation, military blockade and the challenges of living in a conflict-affected area. Participants were interviewed to determine whether culturally specific modes of coping were used. Thematic analysis was applied. The use of resistance and more specifically, sumud , being steadfast and persevering, were identified alongside the motivation to persevere and other adaptive responses to living conditions. Coping strategies identified in this study include adapting, problem-solving, accepting reality, exercising patience, utilising social support, and faith in God (iman) and religion. The implications of this study and the relevance of the findings to mental health and disaster relief are considered

An expanding culture of control? The municipal administrative sanctions Act in Belgium

This article provides an in-depth study of the Act on Municipal Administrative Sanctions 1999 (MAS), which is the first major piece of legislation regulating antisocial behaviour in Belgium. MAS provides municipalities with an instrument to sanction antisocial behaviour and conduct perceived to disturb public order. The article uses Garland’s(2001) thesisonthecultureofcontroltoanalysewhetherMAShasledtoincreasedgovernmentcontrol and the exclusion of significant groups of the population. The research is based on a multiple case study in which the application of MAS was analysed over a 25-year period of security policies in Belgium (1985–2010). The Act’s implementation was studied in the two Belgian cities of Antwerp and Liège in order to consider the influence of the Flemish government and the Walloon government, respectively, in this policy area. The article uses insights from this comparison to revisit the culture of control thesis and its limitations in understanding the political competition that exists over the formulation of policies on antisocial behaviour. Effective Protection of Fundamental Rights in a pluralist worl

Efficient Construction of an Inverted Minimal H1 Promoter Driven siRNA Expression Cassette: Facilitation of Promoter and siRNA Sequence Exchange

RNA interference (RNAi), mediated by small interfering RNA (siRNA), is an effective method used to silence gene expression at the post-transcriptional level. Upon introduction into target cells, siRNAs incorporate into the RNA-induced silencing complex (RISC). The antisense strand of the siRNA duplex then "guides" the RISC to the homologous mRNA, leading to target degradation and gene silencing. In recent years, various vector-based siRNA expression systems have been developed which utilize opposing polymerase III promoters to independently drive expression of the sense and antisense strands of the siRNA duplex from the same template.We show here the use of a ligase chain reaction (LCR) to develop a new vector system called pInv-H1 in which a DNA sequence encoding a specific siRNA is placed between two inverted minimal human H1 promoters (approximately 100 bp each). Expression of functional siRNAs from this construct has led to efficient silencing of both reporter and endogenous genes. Furthermore, the inverted H1 promoter-siRNA expression cassette was used to generate a retrovirus vector capable of transducing and silencing expression of the targeted protein by>80% in target cells.The unique design of this construct allows for the efficient exchange of siRNA sequences by the directional cloning of short oligonucleotides via asymmetric restriction sites. This provides a convenient way to test the functionality of different siRNA sequences. Delivery of the siRNA cassette by retroviral transduction suggests that a single copy of the siRNA expression cassette efficiently knocks down gene expression at the protein level. We note that this vector system can potentially be used to generate a random siRNA library. The flexibility of the ligase chain reaction suggests that additional control elements can easily be introduced into this siRNA expression cassette