Influence of quantum confinement on the photoemission from superlattices of optoelectronic materials

We study the photoemission from quantum wire and quantum dot superlattices with graded interfaces of optoelectronic materials on the basis of newly formulated electron dispersion relations in the presence of external photo-excitation. Besides, the influence of a magnetic field on the photoemission from the aforementioned superlattices together with quantum well superlattices in the presence of a quantizing magnetic field has also been studied in this context. It has been observed taking into account HgTe/Hg1-xCdxTe and InxGa1-xAs/InP that the photoemission from these nanostructures increases with increasing photon energy in quantized steps and exhibits oscillatory dependences with the increase in carrier concentration. Besides, the photoemission decreases with increasing light intensity and wavelength, together with the fact that said emission decreases with increasing thickness exhibiting oscillatory spikes. The strong dependences of the photoemission on the light intensity reflects the direct signature of light waves on the carrier energy spectra. The content of this paper finds six applications in the fields of low dimensional systems in general. (C) 2010 Elsevier Ltd. All rights reserved.

Boosting morale and improving performance in the nursing setting

AIM AND BACKGROUND: While the importance of morale is well researched in the nursing literature, strategies and interventions are not so prolific. The complexities of interpersonal relationships within the clinical domain, and the critical issues faced by nurses on a daily basis, indicate that morale, job satisfaction and motivation are essential components in improving workplace efficiency, output and communication amongst staff. Drawing on educational, organizational and psychological literature, this paper argues that the ability to inspire morale in staff is a fundamental indicator of sound leadership and managerial characteristics. EVALUATION AND KEY ISSUES: Four practical concepts that could be implemented in the clinical setting are proposed. These include: role preparation for managers, understanding internal and external motivation, fostering internal motivation in nursing staff, and the importance of attitude when investing in relationships.

Accuracy of absorbed dose in external photon beam radiotherapy : what level is sufficient and how to approach it?

Radiation therapy (RT) plays currently significant role in curative treatments of several cancers. External beam RT is carried out mostly by using megavoltage beams of linear accelerators. Tumor eradication and normal tissue complications correlate to dose absorbed in tissues. Normally this dependence is steep and it is crucial that actual dose within patient accurately correspond to the planned dose. All factors in a RT procedure contain uncertainties requiring strict quality assurance. From hospital physicist´s point of a view, technical quality control (QC), dose calculations and methods for verification of correct treatment location are the most important subjects. Most important factor in technical QC is the verification that radiation production of an accelerator, called output, is within narrow acceptable limits. The output measurements are carried out according to a locally chosen dosimetric QC program defining measurement time interval and action levels. Dose calculation algorithms need to be configured for the accelerators by using measured beam data. The uncertainty of such data sets limits for best achievable calculation accuracy. All these dosimetric measurements require good experience, are workful, take up resources needed for treatments and are prone to several random and systematic sources of errors. Appropriate verification of treatment location is more important in intensity modulated radiation therapy (IMRT) than in conventional RT. This is due to steep dose gradients produced within or close to healthy tissues locating only a few millimetres from the targeted volume. The thesis was concentrated in investigation of the quality of dosimetric measurements, the efficacy of dosimetric QC programs, the verification of measured beam data and the effect of positional errors on the dose received by the major salivary glands in head and neck IMRT. A method was developed for the estimation of the effect of the use of different dosimetric QC programs on the overall uncertainty of dose. Data were provided to facilitate the choice of a sufficient QC program. The method takes into account local output stability and reproducibility of the dosimetric QC measurements. A method based on the model fitting of the results of the QC measurements was proposed for the estimation of both of these factors. The reduction of random measurement errors and optimization of QC procedure were also investigated. A method and suggestions were presented for these purposes. The accuracy of beam data was evaluated in Finnish RT centres. Sufficient accuracy level was estimated for the beam data. A method based on the use of reference beam data was developed for the QC of beam data. Dosimetric and geometric accuracy requirements were evaluated for head and neck IMRT when function of the major salivary glands is intended to be spared. These criteria are based on the dose response obtained for the glands. Random measurement errors could be reduced enabling lowering of action levels and prolongation of measurement time interval from 1 month to even 6 months simultaneously maintaining dose accuracy. The combined effect of the proposed methods, suggestions and criteria was found to facilitate the avoidance of maximal dose errors of up to even about 8 %. In addition, their use may make the strictest recommended overall dose accuracy level of 3 % (1SD) achievable.

Immigrant Associations in the Metropolitan Area of Finland : Forms of Mobilisation, Participation and Representation

This study examines the role of immigrant associations in the societal and political integration of immigrants into Finnish society. The societal focus is on the ability of immigrant associations to mobilise their ethnic group members to participate in the socio-economic, cultural and political domains of Finnish society and in certain cases even beyond. The political integrative aims are the opportunities of immigrant associations to participate and represent the interests of their ethnic group in local and national policy making. This study focuses on associations in the Metropolitan Area of Finland, (Espoo, Helsinki and Vantaa).The qualitative research consisted of 71 interviews conducted with members of immigrant associations and civil servants. These interviews were mainly semi-structured, including some additional open-ended questions. Additional data consisted of documents, planning reports and of follow-up enquiries. -- In the analysis of the data I categorised thirty-two immigrant associations according to the activity forms and the description of the goals by the members. The four categories consisted of integrative, societal, ethno-cultural and transnational immigrant associations. Most of the immigrant associations belonged to the integrative category (15 of 32 associations). On the one hand the aims of these associations are to provide access for their ethnic group members into Finnish society, while on the other to strengthen the ethnic identity of their members by organising ethno-cultural activities. The societal associations only focused on activities with the objective of including immigrants into the Finnish labour market and educational system. The goal of ethno-cultural associations was to strengthen the ethnic identity of their ethnic group members. The transnational associations aimed at improving the living conditions of women and children in the members' country of origin. The possibilities for immigrant associations to mobilise their members depends partly on external financing. Subsidies have been allocated for societal activities in particular. There remains a risk of the crowding out of ethno-cultural activities: something which has already taken place in several European countries. Immigrant associations aim to strengthen the identity of immigrants mainly by organising social and ethno-cultural activities. Another important target was to provide peer support and therapy courses. Additionally, immigrant women's associations offer assistance to women who have encountered violence by providing counselling and in some cases access to shelter. The data showed that there is an ever growing need to pay heed to the well-being of women, children and elderly immigrants. The participation of immigrant associations in the municipalities' integrative issues takes place mainly through cooperative projects. Until the end of the 1990s there had not been much cooperation. The problem with the projects was that they had mainly been managed by civil servants, whereas members from immigrant associations had remained in a more passive position. Representation of immigrant associations in councils has been fairly weak. Immigrant associations are included in the multicultural councils of Espoo and Vantaa, but only in the planning stages. The municipality of Helsinki does not include immigrant associations due to the large number of organisations which causes problems in finding fair, democratic representation. At the national level, the ‘Advisory Board for Ethnic Relations’ – ETNO didn’t chose its members based on membership of ethnic associations, but based on belongingness to one of the larger language groups spoken by the foreign population in Finland. Since ETNO’s third period (2005-2007), the representatives of immigrant associations and ethnic minority groups have been chosen from proposed candidates. Key words: immigrant associations, integration, mobilisation, participation, representation, the Metropolitan area of Finland, immigrant (women), civil servants

The EU and Institutional Twinning in Morocco - An inquiry into the motives of cooperation through discourse ethics

This study examines Institutional Twinning in Morocco as a case of EU cooperation through the pragmatic, ethical and moral logics of reason in Jürgen Habermas’s discourse ethics. As a former accession tool, Twinning was introduced in 2004 for legal approximation in the context of the European Neighborhood Policy. Twinning is a unique instrument in development cooperation from a legal perspective. With its long historical and cultural ties to Europe, Morocco presents an interesting case study of this new form of cooperation. We will analyse motives behind the Twinning projects on illegal immigration, environment legislation and customs reform. As Twinning is a new policy instrument within the ENP context, there is relatively little preceding research, which, in itself, constitutes a reason to inquire into the subject. While introducing useful categories, the approaches discussing “normative power Europe” do not offer methodological tools precise enough to analyse the motives of the Twinning cooperation from a broad ethical standpoint. Helene Sjursen as well as Esther Barbé and Elisabeth Johansson-Nogués have elaborated on Jürgen Habermas’ discourse ethics in determining the extent of altruism in the ENP in general. Situating the analysis in the process-oriented framework of Critical Theory, discourse ethics provides the methodological framework for our research. The case studies reveal that the context in which they operate affects the pragmatic, ethical and moral aspirations of the actors. The utilitarian notion of profit maximization is quite pronounced both in terms of the number of Twinning projects in the economic sphere and the pragmatic logics of reason instrumental to security and trade-related issues. The historical background as well internal processes, however, contribute to defining areas of mutual interest to the actors as well as the motives Morocco and the EU sometimes described as the external projection of internal values. Through its different aspects, Twinning cooperation portrays the functioning of the pragmatic, ethical and moral logics of reason in international relations.

Flow of an electrically conducting non-newtonian fluid between two rotating coaxial cones in the presence of external magnetic field due to an axial current

Bhatnagar and Rathna (Quar. Journ. Mech. Appl. Maths., 1963,16, 329) investigated the flows of Newtonian, Reiner-Rivlin and Rivlin-Ericksen fluids between two rotating coaxial cones. In case of the last two types of fluids, they predicted the breaking of secondary flow field in any meridian plane. We find that such breaking is avoided by the application of a sufficiently strong azimuthal magnetic field arising from a line current along the axis of the cones.

Influence of External Light Waves on the Thermoelectric Power Under Strong Magnetic Field in Ultrathin Films, Quantum Wires and Quantum Dots of Optoelectronic Materials

In this paper, an attempt is made to study the influence of external light waves on the thermoelectric power under strong magnetic field (TPSM) in ultrathin films (UFs), quantum wires (QWs) and quantum dots (QDs) of optoelectronic materials whose unperturbed dispersion relation of the conduction electrons are defined by three and two band models of Kane together with parabolic energy bands on the basis of newly formulated electron dispersion laws in each case. We have plotted the TPSM as functions of film thickness, electron concentration, light intensity and wavelength for UFs, QWs and ODs of InSb, GaAs, Hg1-xCdxTe and In1-xGaxAsyP1-y respectively. It appears from the figures that for UFs, the TPSM increases with increasing thickness in quantum steps, decreases with increasing electron degeneracy exhibiting entirely different types of oscillations and changes with both light intensity and wavelength and these two latter types of plots are the direct signature of light waves on opto-TPSM. For QWs, the opto-TPSM exhibits rectangular oscillations with increasing thickness and shows enhanced spiky oscillations with electron concentration per unit length. For QDs, the opto-TPSM increases with increasing film thickness exhibiting trapezoidal variations which occurs during quantum jumps and the length and breadth of the trapezoids are totally dependent on energy band constants. Under the condition of non-degeneracy, the results of opto-TPSM gets simplified into the well-known form of classical TPSM equation which the function of three constants only and being invariant of the signature of band structure.

Reciprocity relation in scattering by media subjected to an external magnetic field

Krishnan's reciprocity theorem in colloid optics, ρ{variant}u=1+l/ρ{variant}h/1+1/ρ{variant}v is generalised for the case when the scattering medium is subjected to an external orienting field. It is shown theoretically that a general relation of the type IBA=I′AB results in this case, where IBA is the intensity of the component of the scattered light having its electric vector inclined at an angle B to the vertical with the incident light polarised at an angle A to the vertical, the external field direction being parallel to the incident beam. I′AB is the corresponding intensity with the magnetic field parallel of the scattered ray. Experimental verification of the above generalisation is also given.

European Union and the developing nations' external debt : EU-15's debt policy, 1960–2008

This Master's Thesis defines the debt policy of the current European Union Member States towards the developing nations. Since no official policy for debt exists in the EU, it is defined to include debt practices (loans and debt relief in development cooperation) and debt within the EU development policy framework. This study (1) describes how the issue of external debt appears in the development policy framework, (2) compares EU Member States' given loans and debt relief to grants for the developing nations (1960s to the 2000s), and (3) measures the current orientation in ODA of each EU Member State between grant aid and loan aid using the Grant-Loan Index (GLI). Theoretical aspects include reasons for selecting between loans (Bouchet 1987) and grants (Odedokun 2004, O'Brien and Williams 2007), policy context of the EU (Van Reisen 2007) and the meaning of external debt in the set-up between the North and the South. In terms of history, the events and impact of the colonial period (where loans have originated) are overviewed and compared in light of today's policies. Development assistance statistics are derived from the OECD DAC statistics portal and EU development policy framework documents from the EU portal. Methodologically, the structure of this study is from policy analysis (Barrien 1999, Hill 2008, Berndtson 2008), but it has been modified to fit the needs of studying a non-official policy. EU Member States are divided into three groups by Carbone (2007a), the Big-3, Northern and Southern donors, based on common development assistance characteristics. The Grant-Loan Index is used to compare Carbone's model, which measures quality of aid, to the GLI measuring the structure of aid. Results indicate that EU- 15 countries (active in debt practices) differ in terms of timing, stability and equality of debt practices in the long-term (1960s to the 2000s). In terms of current practices, (2000-2008), it is noted that there lies a disparity between the actual practices and the way in which external debt is represented in the development policy framework, although debt practices form a relevant portion of total ODA practices for many EU-15 Member States, the issue itself plays a minor role in development policy documents. Carbone’s group division applies well to the Grant – Loan Index’s results, indicating that countries with similar development policy behaviour have similarities in debt policy behaviour, with one exception: Greece. On the basis of this study, it is concluded that EU development policy framework content in terms of external debt and debt practices are not congruent. The understanding of this disparity between the policy outline and differences in long-term practices is relevant in both, reaching the UN’s Millennium Development Goals, and in the actual process of developing development aid.

Folding a Polymer via Two-Point Interaction with an External Folding Agent: Use of H-Bonding and Charge-Transfer Interactions

A polymer containing electron-rich aromatic donors (1,5-dialkoxynaphthalene (DAN)) was coerced into a folded state by an external folding agent that contained an electron-deficient aromatic acceptor (pyromellitic diimide (PM)) unit. The donor-containing polymer was designed to carry a tertiary amine moiety in the linking segment, which served as an H-bonding site for reinforcing the interaction with the acceptor containing folding agent that also bore a carboxylic acid group. The H-bonding interaction of the carboxylic acid and the tertiary amine brings the PDI unit between two adjacent DAN units along the polymer backbone to induce charge-transfer (C-T) interactions, and this in turn causes the polymer chain to form a pleated structure. Evidence for the formation of such a pleated structure was obtained from NMR titration studies and also by monitoring the C-T band in their UV-visible spectra. By varying the length of the segment that links the PDI acceptor to the carboxylic acid group, we showed that the most effective folding agent was the one that had a single carbon spacer, as evident from the highest value of the association constant. Control experiments with propionic acid clearly demonstrated the importance of the additional C-T interactions for venerating the folded structures. Further, solution viscosity measurements in the presence of varying amounts of the folding agent revealed a gradual stiffening of the chain in the case of the PDI carrying carboxylic acid, whereas no such affect was seen in the case of simple propionic acid. These observations were supported by D FT calculations of the interactions of a dimeric model of the polymer with the various folding agents; here too the stability of the complex was seen to be highest in the case of the single carbon spacer.

Making sense of a transnational merger: Media texts and the (re)construction of power relations

In this study of symbolic power relations in a transnational merger, we suggest that the popular media can provide a significant arena for (re)constructing national identities and power in this kind of dramatic industrial restructuring, and are an under-utilized source of empirical data in research studies. Focusing on the press coverage of a recent Swedish-Finnish merger, we specify and illustrate a particular feature of discursive (re)construction of asymmetric power relations; superior (Swedish) and inferior (Finnish) national identities, which, we argue, are embedded in the history of colonization and domination between the two nations. The findings of the present study lead us to suggest that a lens taken from post-colonial theory is particularly useful in understanding the wider symbolic power implications of international industrial restructuring.

Optimum Design for External Seismic Stability of Geosynthetic Reinforced Soil Walls: Reliability Based Approach

In this paper, an analytical study considering the effect of uncertainties in the seismic analysis of geosynthetic-reinforced soil (GRS) walls is presented. Using limit equilibrium method and assuming sliding wedge failure mechanism, analysis is conducted to evaluate the external stability of GRS walls when subjected to earthquake loads. Target reliability based approach is used to estimate the probability of failure in three modes of failure, viz., sliding, bearing, and eccentricity failure. The properties of reinforced backfill, retained backfill, foundation soil, and geosynthetic reinforcement are treated as random variables. In addition, the uncertainties associated with horizontal seismic acceleration and surcharge load acting on the wall are considered. The optimum length of reinforcement needed to maintain the stability against three modes of failure by targeting various component and system reliability indices is obtained. Studies have also been made to study the influence of various parameters on the seismic stability in three failure modes. The results are compared with those given by first-order second moment method and Monte Carlo simulation methods. In the illustrative example, external stability of the two walls, Gould and Valencia walls, subjected to Northridge earthquake is reexamined.