Three-dimensional imaging of human stem cells using soft X-ray tomography

Three-dimensional imaging of human stem cells using transmission soft X-ray tomography (SXT) is presented for the first time. Major organelle types—nuclei, nucleoli, mitochondria, lysosomes and vesicles—were discriminated at approximately 50 nm spatial resolution without the use of contrast agents, on the basis of measured linear X-ray absorption coefficients and comparison of the size and shape of structures to transmission electron microscopy (TEM) images. In addition, SXT was used to visualize the distribution of a cell surface protein using gold-labelled antibody staining. We present the strengths of SXT, which include excellent spatial resolution (intermediate between that of TEM and light microscopy), the lack of the requirement for fixative or contrast agent that might perturb cellular morphology or produce imaging artefacts, and the ability to produce three-dimensional images of cells without microtome sectioning. Possible applications to studying the differentiation of human stem cells are discussed.     

Biofeedback training opportunities in clinical internship facilities: An extension of the Feuerstein and Schwartz survey.

Surveyed 227 American Psychological Association (APA)-approved and non-APA-approved clinical internship agencies and found that most respondents were interested in training interns in the clinical application of biofeedback. This supports findings of M. Feuerstein and G. E. Schwartz (see record 1978-08510-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

New flow cytometric capabilities at the national flow cytometryresource

The authors provide a brief review of flow cytometry and a broad view of new flow cytometry technologies. A brief introduction to flow cytometry and cell sorting is provided along with a summary of current commercial capabilities. New developments designed to overcome current limitations are described in terms of capabilities and a characterization of their performance. New capabilities include Fourier transform flow cytometry, phase sensitive detection, digital data acquisition, data clustering algorithms, high speed sorting, and slit scanning     

Subjective definitions of tension

To examine the type of proprioceptive information which subjects include in the definition of tension, 52 subjects were asked to indicate the location of where they felt tension while engaging in a simple motor task. Responses indicated that tendon stretch, muscle tension, and other cues are utilized in the subject's definition of tension.     

Highly cited researchers: a moving target

Scientometrics - Highly cited researchers are a category of researchers defined by scientometric rules relating to counts of citations to their scholarly articles. The designation often refers to...     

Academic performance and institutional resources: a cross-country analysis of research universities

Links between institutional academic performance and academic resources are of relevance for university managers, country officials and the public at large. This study aims to shed light on the issues using reliable data on research performance indicators as well as educational and resource indicators from research universities in Spain, Italy, Australia and Canada. The four countries selected for the study represent different academic traditions and belong to different geopolitical regions, yet they have relatively similar higher education systems in terms of student population, institutional resources and research production. Our study explores differences and similarities among them to better assess the performance of research universities from the four countries in a global context. The indicator set includes research production (number of indexed articles per year) and its quality (citation impact and number of highly cited papers), education production (full-time equivalent FTE student load and degree completions per year) and the resource base (annual ordinary expenditure and FTE number of faculty). We consider the raw indicators as well as a set of composite indicators normalised by measures of scale. Across the profile of universities in our complete sample, institutional size is the prime determinant of research production, with systematic differences in quality related to country, research intensity and resourcing level. Our data show that research universities allocate resources to research and education in country-specific and size-specific ways that are reflected in research performance.     

Assessing creativity with divergent thinking tasks: Exploring the reliability and validity of new subjective scoring methods.

Divergent thinking is central to the study of individual differences in creativity, but the traditional scoring systems (assigning points for infrequent responses and summing the points) face well-known problems. After critically reviewing past scoring methods, this article describes a new approach to assessing divergent thinking and appraises its reliability and validity. In our new Top 2 scoring method, participants complete a divergent thinking task and then circle the 2 responses that they think are their most creative responses. Raters then evaluate the responses on a 5-point scale. Regarding reliability, a generalizability analysis showed that subjective ratings of unusual-uses tasks and instances tasks yield dependable scores with only 2 or 3 raters. Regarding validity, a latent-variable study (n=226) predicted divergent thinking from the Big Five factors and their higher-order traits (Plasticity and Stability). Over half of the variance in divergent thinking could be explained by dimensions of personality. The article presents instructions for measuring divergent thinking with the new method. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of solute on discontinuous dynamic recrystallization

A series of Cu–Sn alloys (pure Cu, Cu–0.2Sn, Cu–2Sn and Cu–5Sn) has been prepared to experimentally test the effect of solute on discontinuous dynamic recrystallization (DDRX) as a function of both temperature and strain rate. Hot compression tests were performed and the microstructure was characterized using optical and scanning electron microscopy. Solute additions tend to broaden the peak in the flow stress curve and increase the peak stress, peak strain and steady-state stress. A reduction in the DRX grain size and a retardation of the kinetics of recrystallization are observed with solute additions, although the effect saturates at 2Sn. A recently published, physically based model for DDRX of pure Cu has been extended to include the effect of solute. The effect on the plastic response of the material and the mobility of high-angle grain boundaries was incorporated and, through comparisons between experiment and simulated DRX phenomena, it is concluded that solute must also significantly affect the nucleation stage of DDRX. A model is developed for the effect of solute on the nucleation of DDRX in Cu–Sn alloys and comparisons with experiment indicate that the principal effects are well captured. Important areas for future work are discussed.     

Have your cake and eat it too? Simultaneously pursuing the knowledge-sharing benefits of agile and traditional development approaches

This research examines how organizations manage knowledge-sharing processes in systems development projects that employ both agile and traditional development techniques. Using a longitudinal case study, we draw on one company’s experience with a system implementation that employed a traditional approach during its first phase and then a hybrid, agile-traditional approach in its second phase. By applying an ambidexterity theory lens, we find that the adoption of a hybrid approach allowed the project to continue to exploit the traditional techniques that were working well, abandon techniques that were underperforming, and explore the use of agile techniques in selected areas.     

Mindful revolution or mindless trend? Examining agile development as a management fashion

The growing adoption of agile methods of system development can be seen as broadly consistent with characteristics of a management fashion. However, the extent that fashions relate to how specific organizations actually adopt and use agile remains unclear. Based on five case studies, this research seeks to apply the concepts from management fashion theory to understand how organizations mindfully (or mindlessly) adopt agile methods. We find in some cases that agile appears to be characterized as a short-term, transitory trend, while in others it is embedded in an organization’s processes and culture. We identify three categories that distinguish between fashion patterns during agile adoptions: Crusaders, who exclusively adopt agile in a pure form; Tailors, who integrate agile and traditional approaches to fit their specific circumstances; and Dabblers who employ a few ceremonial agile activities alongside a traditional approach. The results from this study can encourage managerial awareness of the link between fashions and agile development, which can serve to highlight the unique opportunities to enhance mindfulness and avoid the pitfalls of mindlessness. By uncovering insights into the fashion-centric drivers of agile adoption, this research extends past theory related to both mindful innovation and management fashions.