65,740 research outputs found
Cryo-EM map interpretation and protein model-building using iterative map segmentation.
A procedure for building protein chains into maps produced by single-particle electron cryo-microscopy (cryo-EM) is described. The procedure is similar to the way an experienced structural biologist might analyze a map, focusing first on secondary structure elements such as helices and sheets, then varying the contour level to identify connections between these elements. Since the high density in a map typically follows the main-chain of the protein, the main-chain connection between secondary structure elements can often be identified as the unbranched path between them with the highest minimum value along the path. This chain-tracing procedure is then combined with finding side-chain positions based on the presence of density extending away from the main path of the chain, allowing generation of a Cα model. The Cα model is converted to an all-atom model and is refined against the map. We show that this procedure is as effective as other existing methods for interpretation of cryo-EM maps and that it is considerably faster and produces models with fewer chain breaks than our previous methods that were based on approaches developed for crystallographic maps
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Love at the cultural crossroads: Intimacy and commitment in Chinese Canadian relationships
This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 Wiley-BlackwellThe role of culture in romantic relationships has largely been investigated by examining variation between groups, rather than within groups. This study took a within-group approach to examine the influence of Canadian and Chinese cultural identification on gender role egalitarianism, intimacy, and commitment in 60 Chinese Canadian dating couples. Results revealed that men's identification with mainstream Canadian culture was associated with their own and with their partner's greater intimacy, at least in part because of their greater egalitarianism. Conversely, women's identification with mainstream Canadian culture was associated with their partners' lower intimacy. Finally, women's identification with Chinese heritage culture was associated with their greater commitment, and some evidence suggested that this was because of their greater gender role traditionalism
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Attachment and amae in Japanese romantic relationships
This is the post-print version for the Article. The official published version can be accessed from the link below - Copyright @ 2012 John Wiley & SonsAmae is a Japanese term that refers to an individual’s inappropriate behavior when he/she presumes indulgence from a significant other. The link between attachment style and amae has been debated, but few studies have examined this link empirically. This study examined the association of attachment style with amae behavior in Japanese dating couples over a two-week period. Results showed that for Japanese men, anxious attachment was positively associated with their amae behavior, and in turn, with their increased relationship quality. Conversely, avoidant attachment was negatively associated with their amae behavior, and in turn, with their decreased relationship quality.This research was supported by a Postdoctoral Fellowship grant awarded by the Japanese Society for the Promotion of Science to the author
Cognitive distortions as social practices: An examination of cognitive distortions in sex offender treatment froma discursive psychology perpective
This article presents a critique of the concept of cognitive distortion as it has been developed within the domain of sex-offender treatment programme theory and practice. Drawing upon a discursive psychology perspective, it is argued that cognitive distortions should not be considered as mental entities but as social practices. This argument is illustrated by closely examining how offenders’ accounts of their offences during sex offender treatment sessions were organised. Recordings and transcriptions of treatment group sessions were analysed for the occurrence of regular patterns of talk and interaction. This analysis focused on how minimisation was achieved through well documented rhetorical and conversational devices (conversational repair, narrative contrast devices). An orientation to cognitive distortions as a resource was also illustrated through examining its use by group members to admonish a focus offender and through a narrative reflexivity device. These findings suggest that the notion of cognitive distortion and its role in treatment settings should be reconsidered. Furthermore, it is suggested that a discursive psychology perspective can also make a highly relevant contribution to the evaluation of treatment group processes and that further research is needed in order to examine in detail the way that treatment groups are socially organised
Increasing Distributed Generation Penetration using Soft Normally-Open Points
This paper considers the effects of various voltage control solutions on facilitating an increase in allowable levels of distributed generation installation before voltage violations occur. In particular, the voltage control solution that is focused on is the implementation of `soft' normally-open points (SNOPs), a term which refers to power electronic devices installed in place of a normally-open point in a medium-voltage distribution network which allows for control of real and reactive power flows between each end point of its installation sites. While other benefits of SNOP installation are discussed, the intent of this paper is to determine whether SNOPs are a viable alternative to other voltage control strategies for this particular application. As such, the SNOPs ability to affect the voltage profile along feeders within a distribution system is focused on with other voltage control options used for comparative purposes. Results from studies on multiple network models with varying topologies are presented and a case study which considers economic benefits of increasing feasible DG penetration is also given
Towards a New Framework for Product Development
In the mid-1980s, Andreasen and Hein first described their model of Integrated Product Development. Many Danish companies quickly embraced the principles of integrated product development and adapted the model to their specific business and product context. However, there is concern amongst many Danish companies that Integrated Product Development no longer provides a sufficient way of describing industry’s product development activity. More specifically, five of these companies have supported a programme of research activities at the Technical University of Denmark, which seeks to develop a new framework for product development. This paper will describe the research approach being taken, present some initial findings, and outline a vision of a new working approach to product development
A network model to assess base-filter combinations
Granular filters retain base material within the narrowest constrictions of their void network. A direct comparison of the base material particle size distribution (PSD) and the filter constriction size distribution (CSD) cannot easily be used to assess fi lter - base compatibility. Here a conceptually simple random - walk network model using a filter CSD derived from discrete element modelling and base PSD is used to assess filter - base compatibility. Following verification using experimental data the model is a pplied to assess empirical ratios between filter and base characteristic diameters. The effects of filter density, void connectivity and blocking in the first few filter layers are highlighted
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Protecting the flight test programme
Considerable effort is put into the safety risk assessment of any flight test programme - and rightly so, since failures to apply best practice in this area may cause significant expense, and in extremis loss of life.
However, it must also be remembered that the flight test programme itself is an essential component in the development of the aircraft or system, and that even if safety is never compromised, the failure of a test programme to deliver the required results on time and budget can cause failure of the entire aircraft programme.
This paper considers the areas in which planning and conduct of a flight test programme should be protected. In particular it considers the conduct of flight test personnel in ways which go beyond only safety training, the important of documenting all flight test planning and conduct and the continuous justification of flight test conclusions, planning project manning to ensure that the loss (for whatever reason) of key personnel or equipment does not cause complete failure of the flight test programme, how to recover from significant programme disruptions, and most importantly whilst protecting or recovering the flight test programme – how to ensure that safety is not compromised in the process
PLASMON EFFECTS IN SOLID-STATE RADIATION DETECTORS
We have examined the role of plasmons on the electron energy response of solid-state (Si and Ge) radiation detectors. We found that at the level of parts per thousand, internal-conversion electron calibration techniques do not suffice to yield an adequate response function. In particular, spectral distortions in the detection of low-energy beta-particles have been found which are not accounted for by the usual calibration methods. Thus, a small but significant error can arise from energy loss to low-energy plasmons in Si and Ge detectors. The proximity of the plasmon energy to the end-point singularity and the quadratic form of the beta-decay spectrum may account for the effect interpreted as a 17 keV neutrino. Similar errors can also arise in other subtle solid-state measurements as, for example, in the X-ray edge absorption and emission spectra of metals and semiconductors
PROPERTIES OF GRANULAR HIGH-TC SUPERCONDUCTORS IN AN EFFECTIVE MEDIUM THEORY
The authors consider the transport, electromagnetic and thermodynamic properties of a granular high-Tc superconductor by constructing a model of weakly coupled (Josephson junctions) superconducting and normal grains. They start by using an effective medium theory (EMT), for the conductivity and susceptibility, which is supplemented by London electrodynamics for the superconducting grains, in the limit of weak magnetic field and zero transport current. Next the authors assume a Gaussian distribution of junction resistances R, with mean Ro and variance sigma , which determines the Josephson coupling energy between grains. The criterion that this energy must be greater than kT for superconducting clusters enables them to determine the superconducting fraction cs as a function of temperature. With this they complete the determination of the conductivity and susceptibility of their model. The authors also discuss the specific heat, neglecting fluctuations, which is directly proportional to cs, in their approximation. Throughout this paper, they adopt the Ginzburg-Landau (GL) expressions for the energy gap Delta (order parameter), which is valid near Tc and for the specific heat CH, but they allow for possible deviations of numerical coefficients in these expressions from the Bardeen, Cooper and Schrieffer (BCS) microscopic theory, by introducing phenomenological parameters. The authors find, in accord with experiments, differences between the temperatures of zero resistivity, of resistivity drop and for maximum Meissner effect
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