1,578 research outputs found
Organizational Learning: Leading Innovations
This article examines the interplay among the environment, learning, leaders, and innovations in school systems.Six conditions that, together, have potential to shape an environment that supports organizational learning are illustrated with data from two leaders of innovation: one in an environment that resisted change; the other in a supportive environment.In one case, the environment limited what a leader of innovation could accomplish.In the other case, a supportive environment allowed the leader to influence widespread change, including a situation where one school’s loss of good principals became a gain for the broader profession.Data suggested that modeling is a powerful way to lead and that innovations provide a natural springboard for organizational learning and the emergence of leaders.Findings also demonstrated the importance of innovations, risk taking, collaboration, and communication for organizational improvement
Twisting type-N vacuum fields with a group
We derive the equations corresponding to twisting type-N vacuum gravitational
fields with one Killing vector and one homothetic Killing vector by using the
same approach as that developed by one of us in order to treat the case with
two non-commuting Killing vectors. We study the case when the homothetic
parameter takes the value -1, which is shown to admit a reduction to a
third-order real ordinary differential equation for this problem, similar to
that previously obtained by one of us when two Killing vectors are present.Comment: LaTeX, 11 pages. To be published in Classical and Quantum Gravit
Talking about weight talk : primary care practitioner knowledge, attitudes and practice
Background: Primary care practitioners (PCPs) have a vital role in patient weight management. This study investigates knowledge, attitudes and practice of UK PCPs regarding patient weight management. Methods: A cross-sectional questionnaire assessed PCP perceived knowledge, self-reported practice, attitudes towards overweight/obesity and actual knowledge regarding overweight and obesity management. Practitioners from NE Scotland were invited to participate. Results: Participants comprised 107 PCPs. Most participants viewed management of overweight and obesity as core to their roles and 75% reported discussing weight with overweight/obese patients. Management techniques included discussion and advice provision. Behavioural change techniques (BCTs) were reported infrequently, despite perceptions that patients lacked motivation to lose weight. A quarter of participants reported a lack of training and a third reported inadequate skills to manage overweight/obese patients. Mean percent correct for knowledge questions was approximately 53%. Barriers to patient weight management included lack of specialists for referral and limited time. Conclusions: This study confirmed a primary care role in managing weight in overweight/obese patients. Our finding that most participants reported discussing weight with their overweight or obese patients is unsupported by previously published research, however, a more comprehensive sample of practitioners is required to scrutinize this disparity. Incongruence exists between practitioners’ perceptions of difficulties associated with patient weight loss and the tools they use to address them. Inclusion of training in BCT, the provision of weight care specialists, or referral on to commercial weight loss organizations may provide more effective pathways for PCPs to assist weight loss for overweight/obese patients in primary care.PostprintPeer reviewe
Selling digital services abroad: How do extrinsic attributes influence foreign consumers’ purchase intentions?
© 2017 The Authors This article investigates, through the country-of-origin effect and value-in-use lenses, how the implementation of digital services creates opportunities for cultural industries to expand internationally. We argue that intrinsic attributes of cultural content such as the capacity to entertain are difficult to parameterize because they are somewhat experiential and subjective. This means that extrinsic cues are essential to foreign consumers when making a decision to purchase digital services. We specifically evaluate the influence of Britishness, cultural distance, exoticness, brand image, and flag-brand congruence on the purchase intentions of consumers in foreign markets. This study employs a unique consumer dataset with information on the internationalization of British cultural digital services. The depth and breadth of the survey data collected through collaboration with a UK media industry partner with a globally recognised brand is significantly richer than data used in previous studies. In particular, the study exploits a survey with 5,200 usable data points from consumers residing in fourteen geographically dispersed countries. Findings support theoretical predictions that Britishness, cultural distance, exoticness, brand image and flag-brand congruence are positively linked to the purchasing decisions. Theoretical and managerial implications are discussed
New first integral for twisting type-N vacuum gravitational fields with two non-commuting Killing vectors
A new first integral for the equations corresponding to twisting type-N
vacuum gravitational fields with two non-commuting Killing vectors is
introduced. A new reduction of the problem to a complex second-order ordinary
differential equation is given. Alternatively, the mentioned first integral can
be used in order to provide a first integral of the second-order complex
equation introduced in a previous treatment of the problem.Comment: 7 pages, LaTeX, uses ioplppt.sty and iopl12.sty; to be published in
Class. Quantum Gra
Hidden Symmetry of Higher Dimensional Kerr-NUT-AdS Spacetimes
It is well known that 4-dimensional Kerr-NUT-AdS spacetime possesses the
hidden symmetry associated with the Killing-Yano tensor. This tensor is
"universal" in the sense that there exist coordinates where it does not depend
on any of the free parameters of the metric. Recently the general higher
dimensional Kerr-NUT-AdS solutions of the Einstein equations were obtained. We
demonstrate that all these metrics with arbitrary rotation and NUT parameters
admit a universal Killing-Yano tensor. We give an explicit presentation of the
Killing-Yano and Killing tensors and briefly discuss their properties.Comment: 4 pages, some discussion and references are adde
Generalized Taub-NUT metrics and Killing-Yano tensors
A necessary condition that a St\"ackel-Killing tensor of valence 2 be the
contracted product of a Killing-Yano tensor of valence 2 with itself is
re-derived for a Riemannian manifold. This condition is applied to the
generalized Euclidean Taub-NUT metrics which admit a Kepler type symmetry. It
is shown that in general the St\"ackel-Killing tensors involved in the
Runge-Lenz vector cannot be expressed as a product of Killing-Yano tensors. The
only exception is the original Taub-NUT metric.Comment: 14 pages, LaTeX. Final version to appear in J.Phys.A:Math.Ge
Petrov types of slowly rotating fluid balls
Circularly rotating axisymmetric perfect fluid space-times are investigated
to second order in the small angular velocity. The conditions of various
special Petrov types are solved in a comoving tetrad formalism. A number of
theorems are stated on the possible Petrov types of various fluid models. It is
shown that Petrov type II solutions must reduce to the de Sitter spacetime in
the static limit. Two space-times with a physically satisfactory
energy-momentum tensor are investigated in detail. For the rotating
incompressible fluid, it is proven that the Petrov type cannot be D. The
equation of the rotation function can be solved for the Tolman type
IV fluid in terms of quadratures. It is also shown that the rotating version of
the Tolman IV space-time cannot be Petrov type D.Comment: 14 pages, version to appear in Gen. Rel. Gra
Composition and activity of the non-canonical Gram-positive SecY2 complex
The accessory Sec system in Streptococcus gordonii DL1 is a specialized export system that transports a large serine-rich repeat protein, Hsa, to the bacterial surface. The system is composed of core proteins SecA2 and SecY2 and accessory Sec proteins Asp1–Asp5. Similar to canonical SecYEG, SecY2 forms a channel for translocation of the Hsa adhesin across the cytoplasmic membrane. Accessory Sec proteins Asp4 and Asp5 have been suggested to work alongside SecY2 to form the translocon, similar to the associated SecY, SecE, and SecG of the canonical system (SecYEG). To test this theory, S. gordonii secY2, asp4, and asp5 were co-expressed in Escherichia coli. The resultant complex was subsequently purified, and its composition was confirmed by mass spectrometry to be SecY2-Asp4-Asp5. Like SecYEG, the non-canonical complex activates the ATPase activity of the SecA motor (SecA2). This study also shows that Asp4 and Asp5 are necessary for optimal adhesion of S. gordonii to glycoproteins gp340 and fibronectin, known Hsa binding partners, as well as for early stage biofilm formation. This work opens new avenues for understanding the structure and function of the accessory Sec system
An AP-1/clathrin coat plays a novel and essential role in forming the Weibel-Palade bodies of endothelial cells
Clathrin provides an external scaffold to form small 50–100-nm transport vesicles. In contrast, formation of much larger dense-cored secretory granules is driven by selective aggregation of internal cargo at the trans-Golgi network; the only known role of clathrin in dense-cored secretory granules formation is to remove missorted proteins by small, coated vesicles during maturation of these spherical organelles. The formation of Weibel-Palade bodies (WPBs) is also cargo driven, but these are cigar-shaped organelles up to 5 μm long. We hypothesized that a cytoplasmic coat might be required to make these very different structures, and we found that new and forming WPBs are extensively, sometimes completely, coated. Overexpression of an AP-180 truncation mutant that prevents clathrin coat formation or reduced AP-1 expression by small interfering RNA both block WPB formation. We propose that, in contrast to other secretory granules, cargo aggregation alone is not sufficient to form immature WPBs and that an external scaffold that contains AP-1 and clathrin is essential
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