Wear studies made of slip rings and gas bearing components

Neutron activation analysis techniques were employed for the study of the wear and performance characteristics of slip ring and rotor assemblies and of the problems arising from environmental conditions with special reference to surface contamination. Results showed that the techniques could be successfully applied to measurement of wear parameters

Analysis of solid-rocket effluents for aluminum, silicon, and other trace elements by neutron activation analysis

The sensitivity and reliability of neutron activation analysis in detecting trace elements in solid rocket effluents are discussed. Special attention was given to Al and Si contaminants. The construction and performance of a thermal column irradiation unit was reported

Ant colonies: building complex organizations with minuscule brains and no leaders

Thus far the articles in the series JOD calls the “Organization Zoo” have employed the notion of a “zoo” metaphorically to describe an array of human institutions. Here we take the term literally to consider the design of the most complex organizations in the living world beside those of humans, a favorite of insect zoos around the world: ant colonies. We consider individuality and group identity in the functioning of ant organizations; advantages of a flat organization without hierarchies or leaders; self-organization; direct and indirect communication; job specialization; labor coordination; and the role of errors in innovation. The likely value and limitations of comparing ant and human organizations are briefly examined

Measuring Cognitive Reflection without Maths: Development and Validation fo the Verbal Cognitive Reflection Test

The Cognitive Reflection Test (CRT) became popular for its impressive power to predict how well people reason and make decisions. Despite the popularity of the CRT, a major issue complicates its interpretation: the numerical nature of the CRT confounds reflection ability with mathematical ability. We have addressed this issue by developing the Verbal CRT (CRT-V), a novel 10-item measure of cognitive reflection (https://osf.io/xehbv/), using non-mathematical problems with good statistical and psychometric properties and with low familiarity. First, we selected suitable items with relatively low familiarity and optimal difficulty as identified in two different populations (Studies 1 and 2) and with high content validity as judged by an expert panel (Study 3). Second, we demonstrated good criterion and construct validity for the test in different populations with a wide range of variables (Studies 4-6, 8) and a good internal consistency and test-retest reliability (Study 7). The Verbal CRT was less associated with math anxiety, objective and subjective numeracy than the original CRT and it was test equivalent across gender, age groups and administration setting. In contrast with the original CRT (Hedge’s g = 0.29, 95% CI[0.17, 0.40]), the Verbal CRT showed no gender differences (Hedge’s g = -0.06, 95% CI[-0.18, 0.06]). The Verbal CRT can complement existing, numerical, tests of cognitive reflection

Design and validation of a three-instrument toolkit for the assessment of competence in electrocardiogram rhythm recognition

Background: Rapid and accurate interpretation of cardiac arrhythmias by nurses has been linked with safe practice and positive patient outcomes. Although training in electrocardiogram (ECG) rhythm recognition is part of most undergraduate nursing programmes, research continues to suggest that nurses and nursing students lack competence in recognising cardiac rhythms. In order to promote patient safety, nursing educators must develop valid and reliable assessment tools that allow the rigorous assessment of this competence before nursing students are allowed to practise without supervision. Aim: To develop and psychometrically evaluate a toolkit to holistically assess competence in ECG rhythm recognition. Methods: Following a convenience sampling technique, 293 nursing students from a nursing faculty in a Spanish university were recruited for the study. The following three instruments were developed and psychometrically tested: a knowledge assessment tool (ECG-KAT), a skills assessment tool (ECG-SAT) and a self-efficacy assessment tool (ECG-SES). Reliability and validity (content, criterion and construct) of these tools were meticulously examined. Results: A high Cronbach’s alpha coefficient demonstrated the excellent reliability of the instruments (ECG-KAT=0.89; ECG-SAT=0.93; ECG-SES=0.98). An excellent context validity index (S-CVI/Ave>0.94) and very good criterion validity were evidenced for all the tools. Regarding construct validity, principal component analysis revealed that all items comprising the instruments contributed to measure knowledge, skills or self-efficacy in ECG rhythm recognition. Moreover, known-groups analysis showed the tools’ ability to detect expected differences in competence between groups with different training experiences. Conclusion: The three-instrument toolkit developed showed excellent psychometric properties for measuring competence in ECG rhythm recognition

Recombinant MVA-prime elicits neutralizing antibody responses by inducing antigen-specific B cells in the germinal center.

The RV144 HIV-1 vaccine trial has been the only clinical trial to date that has shown any degree of efficacy and associated with the presence of vaccine-elicited HIV-1 envelope-specific binding antibody and CD4+ T-cell responses. This trial also showed that a vector-prime protein boost combined vaccine strategy was better than when used alone. Here we have studied three different priming vectors-plasmid DNA, recombinant MVA, and recombinant VSV, all encoding clade C transmitted/founder Env 1086 C gp140, for priming three groups of six non-human primates each, followed by a protein boost with adjuvanted 1086 C gp120 protein. Our data showed that MVA-priming favors the development of higher antibody binding titers and neutralizing activity compared with other vectors. Analyses of the draining lymph nodes revealed that MVA-prime induced increased germinal center reactivity characterized by higher frequencies of germinal center (PNA <sup>hi</sup> ) B cells, higher frequencies of antigen-specific B-cell responses as well as an increased frequency of the highly differentiated (ICOS <sup>hi</sup> CD150 <sup>lo</sup> ) Tfh-cell subset

External agents of change: a 10-year trend study of garden visitor behaviour in England.

Changes in people’s behaviour over time can be understood through three distinct elements: their age, a period of time and their birth cohort. Age is a key demographic in many leisure studies but less frequently a period of years is used in longitudinal studies. Changes to a birth cohort (a term often used synonymously with a generation) are rarely examined. This study adopts all three measures to demonstrate the complexity of change over time and also offers a greater understanding of change in people’s leisure behaviour, specifically those who visit gardens in England. A trend study consisting of two cross-sectional studies, 10 years apart, was undertaken through resident surveys (n = 341 and 392). These examined factors external to the individual which might influence their behaviour. The results demonstrate that changes in environmental, social and technological factors such as the weather, family and friends and the Internet have impacts that are complex and which are sometimes concealed within different age groups and cohorts over the decade. Notably, no single factor was identified where there was change across the period, all the age groups and all five cohorts, confirming that any change in people’s behaviour is not universal

On the Multi-Language Construction

Modern software is no more developed in a single programming language. Instead, programmers tend to exploit cross-language interoperability mechanisms to combine code stemming from different languages, and thus yielding fully-fledged multi-language programs. Whilst this approach enables developers to benefit from the strengths of each single-language, on the other hand it complicates the semantics of such programs. Indeed, the resulting multi-language does not meet any of the semantics of the combined languages. In this paper, we broaden the boundary functions-based approach a la Matthews and Findler to propose an algebraic framework that provides a constructive mathematical notion of multi-language able to determine its semantics. The aim of this work is to overcome the lack of a formal method (resp., model) to design (resp., represent) a multi-language, regardless of the inherent nature of the underlying languages. We show that our construction ensures the uniqueness of the semantic function (i.e., the multi-language semantics induced by the combined languages) by proving the initiality of the term model (i.e., the abstract syntax of the multi-language) in its category

Two-Photon Microscopy for Non-Invasive, Quantitative Monitoring of Stem Cell Differentiation

BACKGROUND: The engineering of functional tissues is a complex multi-stage process, the success of which depends on the careful control of culture conditions and ultimately tissue maturation. To enable the efficient optimization of tissue development protocols, techniques suitable for monitoring the effects of added stimuli and induced tissue changes are needed. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present the quantitative use of two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) as a noninvasive means to monitor the differentiation of human mesenchymal stem cells (hMSCs) using entirely endogenous sources of contrast. We demonstrate that the individual fluorescence contribution from the intrinsic cellular fluorophores NAD(P)H, flavoproteins and lipofuscin can be extracted from TPEF images and monitored dynamically from the same cell population over time. Using the redox ratio, calculated from the contributions of NAD(P)H and flavoproteins, we identify distinct patterns in the evolution of the metabolic activity of hMSCs maintained in either propagation, osteogenic or adipogenic differentiation media. The differentiation of these cells is mirrored by changes in cell morphology apparent in high resolution TPEF images and by the detection of collagen production via SHG imaging. Finally, we find dramatic increases in lipofuscin levels in hMSCs maintained at 20% oxygen vs. those in 5% oxygen, establishing the use of this chromophore as a potential biomarker for oxidative stress. CONCLUSIONS/SIGNIFICANCE: In this study we demonstrate that it is possible to monitor the metabolic activity, morphology, ECM production and oxidative stress of hMSCs in a non-invasive manner. This is accomplished using generally available multiphoton microscopy equipment and simple data analysis techniques, such that the method can widely adopted by laboratories with a diversity of comparable equipment. This method therefore represents a powerful tool, which enables researchers to monitor engineered tissues and optimize culture conditions in a near real time manner

The Digital Transformation of Search and Recombination in the Innovation Function: Tensions and an Integrative Framework*

Search and recombination are important mechanisms in the creativity phase of innovation. Digital transformation and the resulting pervasive digitalization of the innovation function have often been associated with increasing possibilities for search and recombination. In this paper, by systematically integrating the search and recombination literature with the literature on digitalization, we demonstrate that digitalization may engender new idiosyncratic tensions in the organizational antecedents of search and recombination and, by implication, in their likely outcomes. We propose that, depending on the interactions among the idiosyncratic tensions identified herein, knowledge recombination might spur very different outcomes, including knowledge layering, knowledge integration, knowledge grafting, or even no recombination at all (which we label “search for the sake of search”). These outcomes may not always be the initially planned desired outcomes. Finally, we provide implications of our integrative framework pertaining to product development and to organizing for innovation