177,160 research outputs found
Managing Triads in a Military Avionics Service Maintenance Network in Taiwan
Purpose – The purpose of this paper is to investigate how different types of
triad structures, and the management mechanisms adopted by the focal company,
affect cooperative performance. Design/methodology/approach – This paper uses a
social network perspective to examine the triad management phenomenon in the
military avionics maintenance context, which is closely associated with the
field of operations management. Findings – This paper demonstrates that
different triad structures and management mechanisms influence perceived
cooperative performance. Four main findings emerged: in a triad, a firm playing
a bridging role perceives higher cooperative performance than when playing a
peripheral role in the triad or being located in a fully connected triad. When a
firm plays the bridging role in a triad, and has a high level of trust, this
leads to higher perceived cooperative performance. When a firm plays a
peripheral role in a triad, high levels of coordination mechanism combined with
high levels of trust result in higher levels of perceived cooperative
performance. In a fully linked triad, when the coordination mechanism is well
developed, the level of trust is high, so that the resulting level of perceived
cooperation is high. Originality/value – This paper extends the knowledge of
triad management by providing an in-depth study of a well-defined network
setting with exceptionally high-level access to the most senior executives. In
practice, this paper shows how to manage differen
An efficient counting method for the colored triad census
The triad census is an important approach to understand local structure in
network science, providing comprehensive assessments of the observed relational
configurations between triples of actors in a network. However, researchers are
often interested in combinations of relational and categorical nodal
attributes. In this case, it is desirable to account for the label, or color,
of the nodes in the triad census. In this paper, we describe an efficient
algorithm for constructing the colored triad census, based, in part, on
existing methods for the classic triad census. We evaluate the performance of
the algorithm using empirical and simulated data for both undirected and
directed graphs. The results of the simulation demonstrate that the proposed
algorithm reduces computational time many-fold over the naive approach. We also
apply the colored triad census to the Zachary karate club network dataset. We
simultaneously show the efficiency of the algorithm, and a way to conduct a
statistical test on the census by forming a null distribution from 1,000
realizations of a mixing-matrix conditioned graph and comparing the observed
colored triad counts to the expected. From this, we demonstrate the method's
utility in our discussion of results about homophily, heterophily, and
bridging, simultaneously gained via the colored triad census. In sum, the
proposed algorithm for the colored triad census brings novel utility to social
network analysis in an efficient package
The first histidine triad motif of phtd is critical for zinc homeostasis in Streptococcus pneumoniae
Streptococcus pneumoniae is the world's foremost human pathogen. Acquisition of the first row transition metal ion zinc is essential for pneumococcal colonization and disease. Zinc is acquired via the ATP-binding cassette transporter AdcCB and two zinc-binding proteins, AdcA and AdcAII. We have previously shown that AdcAII is reliant upon the polyhistidine triad (Pht) proteins to aid in zinc recruitment. Pht proteins generally contain five histidine (His) triad motifs that are believed to facilitate zinc binding and therefore play a significant role in pneumococcal metal ion homeostasis. However, the importance and potential redundancy of these motifs have not been addressed. We examined the effects of mutating each of the five His triad motifs of PhtD. The combination of in vitro growth assays, active zinc uptake, and PhtD expression studies show that the His triad closest to the protein's amino terminus is the most important for zinc acquisition. Intriguingly, in vivo competitive infection studies investigating the amino- and carboxyl-terminal His triad mutants indicate that the motifs have similar importance in colonization. Collectively, our new insights into the contributions of the individual His triad motifs of PhtD, and by extension the other Pht proteins, highlight the crucial role of the first His triad site in zinc acquisition. This study also suggests that the Pht proteins likely play a role beyond zinc acquisition in pneumococcal virulence
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Follicular occlusion triad: an isotopic response or adverse effect of rituximab?
Follicular occlusion triad is a symptom complex of three conditions with a similar pathophysiology including hidradenitis suppurativa (HS), dissecting cellulitis of the scalp, and acne conglobata. Although the exact pathogenesis of the triad is unknown, it appears to be related to follicular occlusion in areas with apocrine glands. Wolf isotopic response refers to the occurrence of a new dermatosis at the site of another, unrelated, previously healed dermatosis. We present a 26-year-old man with a history of pemphigus foliaceus (PF) who developed large draining nodules with scarring and sinus tracts, compatible with follicular occlusion triad, preferentially at areas previously affected by PF thirteen months after treatment with rituximab. To the authors' knowledge there are no reported cases of follicular occlusion triad or HS manifesting as an isotopic response. However, one member of the triad, HS, has been reported to occur infrequently following the use of biologic agents such as adalimumab, infliximab, tocilizumab, and rituximab for chronic immune-mediated inflammatory diseases (psoriasis, Crohn disease, rheumatoid arthritis, and ankylosing spondylitis)
Could dark energy be vector-like?
In this paper I explore whether a vector field can be the origin of the
present stage of cosmic acceleration. In order to avoid violations of isotropy,
the vector has be part of a ``cosmic triad'', that is, a set of three identical
vectors pointing in mutually orthogonal spatial directions. A triad is indeed
able to drive a stage of late accelerated expansion in the universe, and there
exist tracking attractors that render cosmic evolution insensitive to initial
conditions. However, as in most other models, the onset of cosmic acceleration
is determined by a parameter that has to be tuned to reproduce current
observations. The triad equation of state can be sufficiently close to minus
one today, and for tachyonic models it might be even less than that. I briefly
analyze linear cosmological perturbation theory in the presence of a triad. It
turns out that the existence of non-vanishing spatial vectors invalidates the
decomposition theorem, i.e. scalar, vector and tensor perturbations do not
decouple from each other. In a simplified case it is possible to analytically
study the stability of the triad along the different cosmological attractors.
The triad is classically stable during inflation, radiation and matter
domination, but it is unstable during (late-time) cosmic acceleration. I argue
that this instability is not likely to have a significant impact at present.Comment: 28 pages, 6 figures. Uses RevTeX4. v2: Discussion about relation to
phantoms added and additional references cite
Phase and precession evolution in the Burgers equation
We present a phenomenological study of the phase dynamics of the
one-dimensional stochastically forced Burgers equation, and of the same
equation under a Fourier mode reduction on a fractal set. We study the
connection between coherent structures in real space and the evolution of
triads in Fourier space. Concerning the one-dimensional case, we find that
triad phases show alignments and synchronisations that favour energy fluxes
towards small scales --a direct cascade. In addition, strongly dissipative
real-space structures are associated with entangled correlations amongst the
phase precession frequencies and the amplitude evolution of Fourier triads. As
a result, triad precession frequencies show a non-Gaussian distribution with
multiple peaks and fat tails, and there is a significant correlation between
triad precession frequencies and amplitude growth. Links with dynamical systems
approach are briefly discussed, such as the role of unstable critical points in
state space. On the other hand, by reducing the fractal dimension of the
underlying Fourier set, we observe: i) a tendency toward a more Gaussian
statistics, ii) a loss of alignment of triad phases leading to a depletion of
the energy flux, and iii) the simultaneous reduction of the correlation between
the growth of Fourier mode amplitudes and the precession frequencies of triad
phases
The relationship between the Dark Triad traits and help-seeking attitude in high school students
Participants in previous studies on the Dark Triad of personality (Machiavellianism, Psychopathy, and Narcissism) have been mainly college students or older. In the present study, participants were 799 high school students, and the purpose was to identify the factor structure of the Dark Triad and examine differences according to sex, school year, and career direction. Additionally, we investigated the relationship between the Dark Triad and help-seeking attitudes. The results were in line with previous evidence, as the hierarchical factor structure of the Dark Triad was identified. Furthermore, negative influences of Machiavellianism and Psychopathy on help-seeking attitudes were found. On the other hand, there was a positive influence of Narcissism on help-seeking attitudes.Dark Triadとは,マキャベリアニズム,サイコパシー,自己愛傾向の3つの総称である。これまでのDark Triadに関する研究は,大学生以上を対象とした研究が主流である。本研究では,799名の高校生を対象に調査を実施し,Dark Triadの因子構造を確認するとともに,性別,学年,進路による差についても検討し,大学生以上を対象に行われた従来の研究の知見との比較を行うことを目的とした。また,合わせて援助要請との関連についても検討した。その結果,Dark Triadにおいては階層的な因子構造が高校生サンプルにおいても確認された。また,マキャベリアニズム,サイコパシーは援助要請に対してネガティブな関連がみられるのに対して,ナルシシズムはポジティブな関連がみられた
Implications of customer participation in outsourcing noncore services to third parties
Purpose Focal service providers increasingly involve customers in the decision-making about outsourcing parts of the service delivery process to third parties. The present study investigates how customers' outsourcing decisions affect the formation of the waiting experience with the focal service provider, by which the objective waiting time, environmental quality and interactional quality act as focal drivers. Design/methodology/approach To test our hypotheses in the context of cancer care, we gathered process data and experience data by means of a patient observation template (n = 640) and a patient survey (n = 487). The combined data (n = 377) were analyzed using Bayesian models. Findings This study shows that opting for a service triad (i.e. outsourcing non-core services to a third party) deduces customers' attention away from the objective waiting time with the focal service provider but not from the environmental and interactional quality offered by the focal service provider. When the type of service triad coordination is considered, we observe similar effects for a focal service provider-coordinated service triad while in a customer-coordinated service triad the interactional quality is the sole experience driver of waiting experiences that remains significant. Originality/value By investigating the implications of customer participation in the decision-making about outsourcing parts of the service delivery process to third parties, this research contributes to the service design, service triad and service operations literature. Specifically, this study shows that customer outsourcing decisions impact waiting experience formation with the focal service provider.Purpose Focal service providers increasingly involve customers in the decision-making about outsourcing parts of the service delivery process to third parties. The present study investigates how customers' outsourcing decisions affect the formation of the waiting experience with the focal service provider, by which the objective waiting time, environmental quality and interactional quality act as focal drivers. Design/methodology/approach To test our hypotheses in the context of cancer care, we gathered process data and experience data by means of a patient observation template (n = 640) and a patient survey (n = 487). The combined data (n = 377) were analyzed using Bayesian models. Findings This study shows that opting for a service triad (i.e. outsourcing non-core services to a third party) deduces customers' attention away from the objective waiting time with the focal service provider but not from the environmental and interactional quality offered by the focal service provider. When the type of service triad coordination is considered, we observe similar effects for a focal service provider-coordinated service triad while in a customer-coordinated service triad the interactional quality is the sole experience driver of waiting experiences that remains significant. Originality/value By investigating the implications of customer participation in the decision-making about outsourcing parts of the service delivery process to third parties, this research contributes to the service design, service triad and service operations literature. Specifically, this study shows that customer outsourcing decisions impact waiting experience formation with the focal service provider.A
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