4,049 research outputs found
Modelling Work Effort of Workers in the Crowdsourcing Intermediary Market
This study examines crowdsourcing task characteristics (skill variety, task identity, task significance, autonomy, feedback, and task clarity) and the online work situation factor; that is, the trust in evaluations on work effort in the crowdsourcing intermediary market. An e-questionnaire was released as a crowdsourcing task on the Time Fortune website in China; data from 231 valid questionnaires were analyzed using SmartPLS 3 software. Results show that under the conditions of this study, crowdsourcing workers’ internal motivation has a significant positive relationship with their effort. Task autonomy and feedback have significant and positive relationship with internal motivation. Skill variety, task significance, task clarity, and task identity have no significant correlation with internal motivation. However, task clarity has a significant and positive relationship with work effort. The study also finds that the effect of workers’ trust in the task requester on work effort is mediated by internal motivation
Mechanism underlying synergic activation of Tyrosinase promoter by MITF and IRF4
Background: The transcription factor interferon regulatory factor 4 (IRF4) was identified to be involved in human pigmentation by genome-wide association studies (GWASs). The rs12203592-[T/C], which is located in intron 4 of IRF4, shows the strongest link to these pigmentation phenotypes including freckling, sun sensitivity, eye and hair color. Previous studies indicated a functional cooperation of IRF4 with Microphthalmia-associated transcription factor (MITF), a causing gene of Waardenburg syndrome (WS), to synergistically trans-activate Tyrosinase (TYR). However, the underlying mechanism is still unknown. Methods: To investigate the importance of DNA binding in the synergic effect of IRF4. Reporter plasmids with mutant TYR promoters was generated to locate the IRF4 DNA binding sites in the Tyrosinase minimal promoter. By building MITF and IRF4 truncated mutations plasmids, the necessary regions of the synergy functions of these two proteins were also located. Results: The cooperative effect between MITF and IRF4 was specific for TYR promoter. The DNA-binding of IRF4 was critical for the synergic function. IRF4 DNA binding sites in TYR promoter were identified. The Trans-activation domains in IRF4 (aa134-207, aa300-420) were both important for the synergic function, whereas the auto-mask domain (aa207-300) appeared to mask the synergic effect. Mutational analysis in MITF indicated that both DNA-binding and transcriptional activation domains were both required for this synergic effect. Conclusions: Here we showed that IRF4 potently synergized with MITF to activate the TYR promoter, which was dependent on DNA binding of IRF4. The synergic domains in both IRF4 and MITF were identified by mutational analysis. This identification of IRF4 as a partner for MITF in regulation of TYR may provide an important molecular function for IRF4 in the genesis of melanocytes and the pathogenic mechanism in WS
On Routing Optimization in Networks with Embedded Computational Services
Modern communication networks are increasingly equipped with in-network
computational capabilities and services. Routing in such networks is
significantly more complicated than the traditional routing. A legitimate route
for a flow not only needs to have enough communication and computation
resources, but also has to conform to various application-specific routing
constraints. This paper presents a comprehensive study on routing optimization
problems in networks with embedded computational services. We develop a set of
routing optimization models and derive low-complexity heuristic routing
algorithms for diverse computation scenarios. For dynamic demands, we also
develop an online routing algorithm with performance guarantees. Through
evaluations over emerging applications on real topologies, we demonstrate that
our models can be flexibly customized to meet the diverse routing requirements
of different computation applications. Our proposed heuristic algorithms
significantly outperform baseline algorithms and can achieve close-to-optimal
performance in various scenarios.Comment: 16 figure
Poly[[[silver(I)-μ-1,4-bis[(imidazol-1-yl)methyl]benzene-κ2 N 3:N 3′-silver(I)-μ-1,4-bis[(imidazol-1-yl)methyl]benzene-κ2 N 3:N 3′] 4,4′-diazenediyldibenzoate] dihydrate]
In the title compound, [Ag2(C14H14N4)2](C14H8N2O4)·2H2O, each of the two unique Ag+ ions is two-coordinated by two N atoms from two different 1,4-bis[(imidazol-1-yl)methyl]benzene ligands in an almost linear fashion [N—Ag—N = 170.34 (10) and 160.25 (10)°]. The 4,4′-diazenediyldibenzoate anions do not coordinate to Ag. O—H⋯O hydrogen bonds stabilize the crystal structure
A Toy Model for Magnetic Connection in Black-Hole Accretion Disc
A toy model for magnetic connection in black hole (BH) accretion disc is
discussed based on a poloidal magnetic field generated by a single electric
current flowing around a Kerr black hole in the equatorial plane. We discuss
the effects of the coexistence of two kinds of magnetic connection (MC) arising
respectively from (1) the closed field lines connecting the BH horizon with the
disc (henceforth MCHD), and (2) the closed field lines connecting the plunging
region with the disc (henceforth MCPD). The magnetic field configuration is
constrained by conservation of magnetic flux and a criterion of the screw
instability of the magnetic field. Two parameters and are introduced to
describe our model instead of resolving the complicated MHD equations. Compared
with MCHD, energy and angular momentum of the plunging particles are extracted
via MCPD more effectively, provided that the BH spin is not very high. It turns
out that negative energy can be delivered to the BH by the plunging particles
without violating the second law of BH thermodynamics, however it cannot be
realized via MCPD in a stable way.Comment: 11 pages, 9 figures, accepted by MNRA
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