Individual Micro Research Articles

Preferential adsorption of polycarboxylate superplasticizers on cement and silica fume in ultra-high performance concrete (UHPC)

UHPC is fluidized particularly well when a blend of MPEG- and APEG-type PCEs is applied. Here, the mechanism for this behavior was investigated. Testing individual cement and micro silica pastes revealed that the MPEG-PCE disperses cement better than silica whereas the APEG-PCE fluidizes silica particularly well. This behavior is explained by preferential adsorption of APEG-PCE on silica while MPEG-PCEs exhibit a more balanced affinity to both cement and silica. Adsorption data obtained from individual cement and micro silica pastes were compared with those found for the fully formulated UHPC containing a cement/silica blend. In the UHPC formulation, both PCEs still exhibit preferential and selective adsorption similar as was observed for individual cement and silica pastes. Preferential adsorption of PCEs is explained by their different stereochemistry whereby the carboxylate groups have to match with the steric position of calcium ions/atoms situated at the surfaces of cement hydrates or silica.

An Empirical Analysis of Determinants of Migration among University Graduates in Albania

The high rates of international migration among the Albanians were also associated by migration of the skilled and highly-skilled driven mainly by economic reasons. This phenomena known as the “brain drain” has recently been one of the most common concerns in Albania, but despite the vast theoretical literature on the consequences of brain drain for developing countries, and the possibility of brain gain, the dedicated research on this topic has been very scarce, especially on the determinants of the brain drain. Regarding this latter topic, a few decades ago the key question was posed by Portes (1976) at the individual level, why do some highly skilled individuals within a country leave, while others stay. Moreover, amongst those who go, why do some return? Such an analysis may provide a first step towards understanding the potential of international migration of the (highly) skilled, the characteristics of the future skilled migrants and the factors that influence their migration decisions. Furthermore, it will help to provide more practical and detailed policy tools. This paper addresses the answer to the first question attempting to explain what determines international migration of the Albanian university graduates. The evidence is drawn from a new survey designed to study the individual level micro and macro-economic determinants of the brain drain. The study is focused on a sample of 1210 last year students of 14 public and private universities in 8 cities in Albania. The survey asks detailed questions on intentions to migrate and return on a range of different push and pull factors and their importance. These factors include individual and family characteristics, migration experience and networks, destination countries, as well as aims, incentives and barriers to international migration at the micro and macro level. Using these data we measure the probability of international migration of the most educated individuals in our country, and examine which characteristics predict their migration. Our results suggest that the determinants of intentions to migrate are of individual, family and macro nature.

Information-Laden Processes under Complexity and Uncertainty: Individual and Team Perspectives

Today’s organizations increasingly rely on teams of individuals to collaboratively collect, share and analyze detailed and disparate information in complex, time-pressured situations. While a substantial body of research provides insights regarding organizational adaptation to unexpected, non-routine events (e.g., Kozlowski & Bell, 2003; 2008, Waller, 1999; Waller, Gupta, & Giambatista, 2004), a number of individual micro and team processes under complexity and uncertainty have not been sufficiently explored from either a theoretical or empirical perspective. The goal of this symposium is to closely investigate specific individual micro and team processes involved in dynamic, complex, information-laden task environments. Specifically, the panelists will take on both individual and team perspectives and discuss: (1) a theoretical framework that integrates the model of threat-rigidity (Staw, Sandelands, & Dutton, 1981) with the concept of enactment (Weick, 1979) to explain individuals’ adaptive or maladaptive responses during discontinuous non-routine events; (2) an empirical investigation of team interaction patterns, revolving around information processing and decision-making under dynamic conditions; (3) a study that explores the nature and timing of information collection and transfer, task prioritization, and task distribution within teams in turbulent task performance settings; and (4) a study that investigates the amount and correlates of variability of trauma team interaction patterns across scenarios. We believe that the papers will advance our understanding of the phenomenon from a theoretical, empirical, and practical perspective and also generate considerable discussion among panelists and audience members.Adaptation to discontinuous nonroutine events: Dual threats and the mediator of fearPresenter: Mary J. Waller; York U.Presenter: Rommel O. Salvador; U. of Massachusetts, AmherstPresenter: Kathleen M. Sutcliffe; U. of Michigan, Ann ArborPatterns of team information processing in times of crisisPresenter: Golchehreh Sohrab; York U.Moving targets: information-laden processes in turbulent timesPresenter: Christopher Fredette; Sprott School of Business, Carleton U.Presenter: Mary J. Waller; York U.Presenter: Zhike Lei; ESMT European School of Management and TechnologyVariability in Effective Interaction Patterns in Medical Trauma TeamsPresenter: Lillian Su; Children’s National Medical CenterPresenter: Mary J. Waller; York U.Presenter: Seth A. Kaplan; George Mason U.

Ethnic Minority Women in the Scottish Labour Market: Employers' Perceptions

This paper contributes to an under-researched area through investigating employers' perceptions of ethnic minority women in the Scottish labour market. Adopting a social constructionist approach which acknowledges agency and structure and incorporates insights relating to organizational and social group culture, the study highlights the influence of individual (micro), organizational (meso) and contextual (macro) factors on ethnic minority women's participation in the labour market. The paper is based on qualitative research involving Scottish employers in the public and private sectors to examine perceptions and practices related to the employment of ethnic minority women. Institutional commitment to equality issues is questioned, although individual instances of engagement with key equality issues were sometimes evident. Proactive recruitment strategies and career support for ethnic minority women and men were not in evidence, and there was low awareness of the unique position of ethnic minority women in employment and society. We argue that these findings call for a multi-level approach to advancing human resources management policy, practice and research within a wider socio-political environment in which the responsibilities and duties of public sector organizations are clarified and more support is provided for organizational promotion of equal opportunities.

Effect of individual and combined addition of micro/nano-sized metallic elements on the microstructure and mechanical properties of pure Mg

In this study, the effects of the addition of individual micro- and nano-sized metallic elements (micron-Ti and nano-Cu) and their combination on the microstructure and mechanical properties of pure Mg were investigated. The materials were produced by rapid microwave sintering assisted powder metallurgy technique followed by hot extrusion. From the microstructural characterization and mechanical property evaluation, it was identified that the solid solubility, size and the method of addition of elements significantly influenced the properties. While the insoluble micron-Ti enhanced the strength and reduced the ductility due to weak interface, the addition of nano-Cu with relative solid solubility enhanced the strength due to the formation of Mg2Cu intermetallics and retained the ductility. The positive effect of their combined addition was found to be more pronounced when they were pre-processed, rather than their direct addition. The change in particle morphology, Ti3Cu intermetallic formation and good interfacial bonding with the matrix achieved due to pre-processing contributed towards its superior strength and ductility.

Predictors of Emergency Department and Outpatient Visits for Hypoglycemia in Type 2 Diabetes: An Analysis of a Large US Administrative Claims Database

Although hypoglycemia is a well-recognized complication of type 1 diabetes and insulin treatment in type 2 diabetes, less research exists on hypoglycemia in the large number of patients with type 2 diabetes who are treated with oral antidiabetic agents. To identify predictors of hypoglycemia-related emergency department (ED) and outpatient visits in patients with type 2 diabetes. We used the 2004-2008 MarketScan database to conduct a nested case-control analysis. Cohort members were 18 years of age or older with type 2 diabetes and taking an oral antidiabetic agent at cohort entry. We required 12 months or more of continuous enrollment in a noncapitated plan and excluded persons with type 1 or gestational diabetes. Within the cohort, we selected 11,375 cases (first outpatient hypoglycemic event) and 68,247 controls using 6:1 incidence density sampling. A conditional logistic regression model estimated the adjusted odds ratios (AORs) and corresponding 95% confidence intervals of predictors. Cases were more likely than controls to have diabetic complications and other comorbidity, and to be using the most antidiabetic or other medications. The presence of individual micro- and macrovascular complications of diabetes increased the relative rate of hypoglycemia. With no antidiabetic drug therapy as the referent (within 30 days preceding the index date), insulin monotherapy (AOR 1.76; 95% CI 1.50 to 2.05) and insulin in combination with other oral antidiabetic agents (AOR 1.80; 95% CI 1.65 to 1.97) had the highest relative rates of hypoglycemia. Metformin monotherapy (AOR 0.65; 95% CI 0.61 to 0.70), thiazolidinedione monotherapy (AOR 0.71; 95% CI 0.63 to 0.79), and dipeptidyl peptidase-4 inhibitor monotherapy (AOR 0.63; 95% CI 0.45 to 0.89) had decreased relative rates of hypoglycemia. Monotherapy with sulfonylureas, other injectable agents, meglitinides or α-glucosidase inhibitors was not predictive. Medications should be prescribed carefully for patients at high risk of hypoglycemia, particularly those with diabetes complications or those taking insulin alone or in combination. Additional studies are needed to carefully examine the nature of the association between diabetes-related complications and hypoglycemic episodes.

Lab-in-a-tube: ultracompact components for on-chip capture and detection of individual micro-/nanoorganisms

A review of present and future on-chip rolled-up devices, which can be used to develop lab-in-a-tube total analysis systems, is presented. Lab-in-a-tube is the integration of numerous rolled-up components into a single device constituting a microsystem of hundreds/thousands of independent units on a chip, each individually capable of sorting, detecting and analyzing singular organisms. Such a system allows for a scale-down of biosensing systems, while at the same time increasing the data collection through a large, smart array of individual biosensors. A close look at these ultracompact components which have been developed over the past decade is given. Methods for the capture of biomaterial are laid out and progress of cell culturing in three-dimensional scaffolding is detailed. Rolled-up optical sensors based on photoluminescence, optomechanics, optofluidics and metamaterials are presented. Magnetic sensors are introduced as well as electrical components including heating, energy storage and resistor devices.

Tax Evasion Indices and Profiles

The aim of the paper is to apply definitions and graphical devices currently used in the economic literature on poverty to individual data on tax evasion. Starting from simple indices, the paper presents composite indices and profiles of tax evasion and compliance, based on the three I’s of tax evasion: incidence, intensity and inequality. In the field of tax evasion, a stream of literature produces potentially a large amount of individual micro data using agent-based models: the aim of the paper is to enrich the analysis offered by these models with indices that take into account the whole distribution of taxpayers’ evasion rates, rather than the usual average rate.

Inkjet printing of individual polymer micro parts self-shaped with hemispherical caps

Droplet deposition has been so ubiquitous over a decade for the production of micro parts using versatile liquid-based methods such as inkjet-printing technology. One of key elements for success in the design involves the use of non-homogeneous substrates to effectively control the complex morphologies of solute deposit during evaporation. However, there are still few studies investigating contours of the solid contents self-formed and even released as the solvents evaporate. This paper reports a droplet vaporization deposition (DVD) method that can significantly improve the controllability over the curvatures of micro parts utilizing the heterogeneous PDMS (Polydimethysiloxane) substrates based on soft-lithography technique. Experimental and analytical results indicate that the profile curvatures and contact angles (up to ∼90°) for the hemispherical parts formed after droplet evaporation were simply varied by different droplet volumes (single droplet ∼10pl) placed on the cavity-structured surfaces, thus providing the capability of control over solid contours. In this way, the individual micro parts released from the mold substrates could be applied in many applications, in particular the current self-assembly processes.

Selective Trapping and Manipulation of Microscale Objects Using Mobile Microvortices

Controlled manipulation of individual micro- and nanoscale objects requires the use of trapping forces that can be focused and translated with high spatial and time resolution. We report a new strategy that uses the flow of mobile microvortices to trap and manipulate single objects in fluid with essentially no restrictions on their material properties. Fluidic trapping forces are generated toward the center of microvortices formed by magnetic microactuators, that is, rotating nanowire or self-assembled microbeads, actuated by a weak rotating magnetic field (|B|< 5 mT). We demonstrate precise manipulation of single microspheres and microorganisms near a solid surface in water.

A novel device for in-situ nanomechanics of 1-D nanostructures

This paper reports the development of an in-situ nanotensilometer that enables highly reliable mechanical tensile testing on individual micro-/nanoscale structures. The device features independent measurement of force and displacement histories in the specimen with nanoNewton force and sub-nanometer displacement resolutions, respectively. Moreover, the device is well suited for in-situ testing of free-standing micro/nanostructures within a high resolution scanning electron microscope, which permits continuous high-resolution imaging of the specimen during straining. In order to conduct the nanomechanical tests the ends of the specimen are attached to the probe tips of the device using electron-beam induced deposition. The general capabilities and features of the nanotensilometer are illustrated by presenting results of nanomechanical tensile tests on electrospun polyaniline microfibers.

Revision of the European Data Protection Directive: opportunity or threat for public health monitoring?

The link between public health monitoring on one hand and data protection legislation on the other may not be immediately clear to all. Nevertheless, it has a strong relation with the conditions required to build and correctly operate high quality, sustainable public health information systems. The following public health goals are directly influenced by the data protection legislative framework: Maintaining systems of EU health indicators1 is central to achieve these goals and can only be realized by integrating data sources in all Member States (MS). However, as a consequence of an uneven implementation of the EU Data Protection Directive (DPD),2 access to individual (micro) data appears to be still limited and heterogeneous, …

Skilled and unskilled wage dynamics in Italy in the 1990s: changes in individual characteristics, institutions, trade and technology

In this paper, we use individual micro data on workers combined with industry and regional data to study the wage dynamics of skilled and unskilled workers in Italy in the 1991–1998 period. In contrast to previous empirical studies, our data make it possible to analyse, within a single framework, the role of many of the factors indicated in the literature as possible determinants of skilled and unskilled wage dynamics: changes in the individual characteristics of workers, changes in labour market institutions, increasing international integration, and skill‐biased technological progress. Our results show that international integration, both in terms of trade in goods and in terms of international labour mobility, plays a role in determining the wage dynamics of skilled (white‐collar) and unskilled (blue‐collar) workers. Moreover, in line with labour economics research, our findings show that the individual characteristics of workers and the institutional variables are more relevant in explaining skilled and unskilled wage dynamics than wage differentials.

Whispering gallery mode enhanced luminescence from an individual ZnO micro- and nanoscaled optical resonator

A whispering gallery mode optical resonator has been achieved using individual ZnO micro- and nanocolumns. Monochromatic cathodoluminescence images of the ZnO micro- and nanocolumns show that enhanced luminescence intensity is located across the profile of the micro- and nanocolumns, and is mainly attributed to the whispering gallery mode (WGM) enhanced emission. The individual hexagonal ZnO micro- and nanocolumns are regarded as an optical resonator structure. Theoretical calculations and computer simulations based on the finite-difference time-domain suggest that the WGMs are generated in the ZnO micro- and nanocolumns, and these results agree closely with the experimental results.

Three forms of trust and their association

This article investigates the relationships between particular social trust, general social trust, and political trust and tests a variety of political, social-psychological, and social capital theories of them. This sort of research has not been carried out before because until the World Values Survey of 2005–07 there has been, to our knowledge, no comparative survey that includes measures of particular and other forms of trust. The new data challenge a common assumption that particular social trust is either harmful or of little importance in modern democracies and shows that it has strong, positive associations with other forms of trust. However, the relationships are not symmetrical and particular social trust seems to be a necessary but not sufficient cause of general social trust, and both forms of social trust appear to be necessary, but not sufficient conditions for political trust. Strong evidence of mutual associations between different forms of trust at both the individual micro level and the contextual macro level supports theories of rainmaker effects, the importance of political institutions, and the significance of social trust for political trust. In more ways than one, social trust, not least of a particular type, seems to have an important bearing on social and political stability.

Strategic Framework for Increasing Accessibility and Utilization of Voluntary Counseling and Testing Services in Uganda

Despite the usefulness of VCT service as an entry point to prevention for the HIV-uninfected people and care, treatment and support for those who test HIV positive, VCT service remains poorly utilized among the fishing communities. The aim of the study was to identify factors influencing VCT service delivery and utilisation among fishing communities in Uganda and consequently, formulated a strategic framework for improving VCT service delivery and utilisation in the fishing communities. The study followed a 3-phased approach, collecting and analyzing quantitative data from Kasenyi fishing community under phase I, collecting and analyzing qualitative data from hospital managers and VCT counselors in phases II and III, respectively. Results indicate that VCT services delivery and utilisation is affected by factors at government (macro) level, the institution (meso) level, and at the individual (micro) level. Based on this, a strategic framework was designed, expected to increase VCT service availability, accessibility, and acceptability if applied. The researcher recommends the use of this useful tool in the design of VCT programs.

A New Individually Addressable Micro-LED Array for Photogenetic Neural Stimulation

Here, we demonstrate the use of a micro light emitting diode (LED) array as a powerful tool for complex spatiotemporal control of photosensitized neurons. The array can generate arbitrary, 2-D, excitation patterns with millisecond and micrometer resolution. In particular, we describe an active matrix control address system to allow simultaneous control of 256 individual micro LEDs. We present the system optically integrated into a microscope environment and patch clamp electrophysiology. The results show that the emitters have sufficient radiance at the required wavelength to stimulate neurons expressing channelrhodopsin-2 (ChR2).

PSO Aided Neuro Fuzzy Inference System for Ultrasound Image Segmentation

Individual micro calcifications are difficult to be detected as they are variable in shape and size and may be embedded in areas of dense parenchymal tissues. One of the most important problems of medical diagnosis, in general, is the subjectivity of the pattern recognition by diagnosis experts. This is due to the fact that the results are depended on the interpretation of the input from the patients but not on systematic procedure. In this paper, an adaptive neuro-fuzzy model optimized by PSO algorithms has been proposed. The symptoms and signs are gathered and the fuzzy membership values are defined. Feed forward multilayer networks are used to accept the fuzzy input values and is trained using back-propagation algorithm. The system is tested for detecting the micro-calcifications in breast sonograms. Later the results are compared for its performance.

Design and fabrication of a flexible three-axial tactile sensor array based on polyimide micromachining

This paper describes the design and fabrication of a flexible three-axial tactile sensor array using advanced polyimide micromachining technologies. The tactile sensor array is comprised of sixteen micro force sensors and it measures 13 mm × 18 mm. Each micro force sensor has a square membrane and four strain gauges, and its force capacity is 0.6 N in the three-axial directions. The optimal positions of the strain gauges are determined by the strain distribution obtained form finite element analysis (FEA). The normal and shear forces are detected by combining responses from four thin-film metal strain gauges embedded in a polyimide membrane. In order to acquire force signals from individual micro force sensors, we fabricated a PCB based on a multiplexer, operational amplifier and microprocessor with CAN network function. The sensor array is tested from the evaluation system with a three-component load cell. The developed sensor array can be applied in robots’ fingertips, as well as to other electronic applications with three-axial force measurement and flexibility keyword requirements.

Interprofessionalism and shared decision-making in primary care: a stepwise approach towards a new model

Most shared decision-making (SDM) models within healthcare have been limited to the patient–physician dyad. As a first step towards promoting an interprofessional approach to SDM in primary care, this article reports how an interprofessional and interdisciplinary group developed and achieved consensus on a new interprofessional SDM model. The key concepts within published reviews of SDM models and interprofessionalism were identified, analysed, and discussed by the group in order to reach consensus on the new interprofessional SDM (IP-SDM) model. The IP-SDM model comprises three levels: the individual (micro) level and two healthcare system (meso and macro) levels. At the individual level, the patient presents with a health condition that requires decision-making and follows a structured process to make an informed, value-based decision in concert with a team of healthcare professionals. The model acknowledges (at the meso level) the influence of individual team members' professional roles including the decision coach and organizational routines. At the macro level it acknowledges the influence of system level factors (i.e. health policies, professional organisations, and social context) on the meso and individual levels. Subsequently, the IP-SDM model will be validated with other stakeholders.