8,064 research outputs found
Performance-based contracting in the defence industry: Exploring triadic dynamics between government, OEMs and suppliers
This study takes a rare longitudinal perspective to examine performance-based contracting (PBC) in
the context of the development of a major capital defence project. It employs a triadic framework to
examine changes in actors and their roles over time in fulfilling the project. The triads involve both
contractors as suppliers and government entities. More specifically, using a historical narrative
method the study suggests that over the 30 year span of the new warship’s development, different
parties occupy the nodes of triads where the roles or functions of the principal and agents in the
contract change over time. Our use of a triadic perspective enables us to trace both the withdrawal of
the government customer from a position of authority and the specific strategy of one supplier to
occupy the vacated role as systems integrator. The study makes three distinct contributions: firstly, to
our understanding of PBC through tracing the development of the conditions that enable PBC in
largescale long-term public-private contracting such as clear role delineation. Second, it adds to
understanding of principal-agent behaviour in triadic public-private projects, suggesting that
customer and supplier roles need to be perceived as supply network dynamics. Third, it suggests
reasons why this defence acquisition underperformed, focusing on the mediation of the customer’s
value requirement through powerful players seeking to extend their control. We argue PBC must be
re-assessed in complex environments to include less direct financial measures such as long-term
market share and adopt a more nuanced approach to contractual management than simply
transferring risk.We wish to acknowledge the financial assistance provided by the Chartered Institute of Purchasing &
Supply and the Institute of Supply Management
MCRS2 represses the transactivation activities of Nrf1
<p>Abstract</p> <p>Background</p> <p>Nrf1 [p45 nuclear factor-erythroid 2 (p45 NF-E2)-related factor 1], a member of the CNC-bZIP (CNC basic region leucine zipper) family, is known to be a transcriptional activator by dimerization with distinct partners, such as Maf, FosB, c-Jun, JunD, etc. The transcriptional roles of CNC-bZIP family are demonstrated to be involved in globin gene expression as well as the antioxidant response. For example, CNC-bZIP factors can regulate the expression of detoxification proteins through AREs, such as expression of human gamma-glutamylcysteine synthetases (GCS), glutathione S-transferases (GST), UDP-glucuronosyl transferase (UDP-GT), NADP (H) quinone oxidoreductase (NQOs), etc. To further explore other factor(s) in cells related to the function of Nrf1, we performed a yeast two-hybrid screening assay to identify any Nrf1-interacting proteins. In this study, we isolated a cDNA encoding residues 126–475 of MCRS2 from the HeLa cell cDNA library. Some functions of MCRS1 and its splice variant-MSP58 and MCRS2 have been previously identified, such as transforming, nucleolar sequestration, ribosomal gene regulation, telomerase inhibition activities, etc. Here, we demonstrated MCRS2 can function as a repressor on the Nrf1-mediated transactivation using both in vitro and in vivo systems.</p> <p>Results</p> <p>To find other proteins interacting with the CNC bZIP domain of Nrf1, the CNC-bZIP region of Nrf1 was used as a bait in a yeast two-hybrid screening assay. MCRS2, a splicing variant of p78/MCRS1, was isolated as the Nrf1-interacting partner from the screenings. The interaction between Nrf1 and MCRS2 was confirmed <it>in vitro </it>by GST pull-down assays and <it>in vivo </it>by co-immunoprecipitation. Further, the Nrf1-MCRS2 interaction domains were mapped to the residues 354–447 of Nrf1 as well as the residues 314–475 of MCRS2 respectively, by yeast two-hybrid and GST pull-down assays. By immunofluorescence, MCRS2-FLAG was shown to colocalize with HA-Nrf1 in the nucleus and didn't result in the redistribution of Nrf1. This suggested the existence of Nrf1-MCRS2 complex in vivo. To further confirm the biological function, a reporter driven by CNC-bZIP protein binding sites was also shown to be repressed by MCRS2 in a transient transfection assay. An artificial reporter gene activated by LexA-Nrf1 was also specifically repressed by MCRS2.</p> <p>Conclusion</p> <p>From the results, we showed MCRS2, a new Nrf1-interacting protein, has a repression effect on Nrf1-mediated transcriptional activation. This was the first ever identified repressor protein related to Nrf1 transactivation.</p
MUSCLE RECRUITMENT SEQUENCE AND TOTAL REACTION TIME DURING A KARATE ROUNDHOUSE KICK
The purpose of the current study is to quantify the muscle recruitment sequence and total reaction time of fourteen national karate athletes and fourteen college karate athletes while performing upper level roundhouse kick. A 16-channel electromyography was used to measured the muscle activities and an instrumented target was for the evaluation of the response time. The experimental results show that both groups recruited the biceps femoris on the kicking (right) side, followed by the right gastrocnemius, but the subsequent muscle firing sequence was slightly different. This resulted in smaller total reaction time of the national group (736.32 ms) than the time of the control group (770.28 ms) because of different across skill level
Hyperbolic Geometric Graph Representation Learning for Hierarchy-imbalance Node Classification
Learning unbiased node representations for imbalanced samples in the graph
has become a more remarkable and important topic. For the graph, a significant
challenge is that the topological properties of the nodes (e.g., locations,
roles) are unbalanced (topology-imbalance), other than the number of training
labeled nodes (quantity-imbalance). Existing studies on topology-imbalance
focus on the location or the local neighborhood structure of nodes, ignoring
the global underlying hierarchical properties of the graph, i.e., hierarchy. In
the real-world scenario, the hierarchical structure of graph data reveals
important topological properties of graphs and is relevant to a wide range of
applications. We find that training labeled nodes with different hierarchical
properties have a significant impact on the node classification tasks and
confirm it in our experiments. It is well known that hyperbolic geometry has a
unique advantage in representing the hierarchical structure of graphs.
Therefore, we attempt to explore the hierarchy-imbalance issue for node
classification of graph neural networks with a novelty perspective of
hyperbolic geometry, including its characteristics and causes. Then, we propose
a novel hyperbolic geometric hierarchy-imbalance learning framework, named
HyperIMBA, to alleviate the hierarchy-imbalance issue caused by uneven
hierarchy-levels and cross-hierarchy connectivity patterns of labeled
nodes.Extensive experimental results demonstrate the superior effectiveness of
HyperIMBA for hierarchy-imbalance node classification tasks.Comment: Accepted by Web Conference (WWW) 202
MiR-214 promotes renal fibrosis in diabetic nephropathy via targeting SOCS1
Purpose: To elucidate how miR-214 regulates the pathogenesis of diabetic nephropathy (DN).
Methods: The extent of fibrosis in DN mice kidneys was examined using Masson’s staining. Quantitative polymerase chain reaction (qPCR) was used to determine the levels of miR-214. Dual luciferase reporter assay was used to identify the target of miR-214. The expression of fibrosis marker proteins of high glucose-stimulated NRK-52E cells transfected with miR-214 was determined using western blotting.
Results: Fibrosis in renal tissue of DN mice was significantly increased and miR-214 was upregulated (p < 0.001). Suppressor of cytokine signaling 1 protein (SOCS1) was the target gene of miR-214, and overexpression of miR-214 promoted fibrosis (p < 0.05, p < 0.001). On the other hand, overexpression of SOCS1 inhibited this process, indicating that miR-214 promoted fibrosis via targeting SOCS1 (p < 0.001). Finally, inhibition of miR-214 c ameliorated renal fibrosis in DN mice (p < 0.01, p < 0.001).
Conclusions: MiR-214 is upregulated in db/db DN mice kidney tissue; miR-214 regulates renal fibrosis in DN mice by targeting SOCS1
Modal analysis and harmonic response analysis of energy-absorbing and anti-scouring columns
Many field observations have found that damage to the support did not increase with the magnitude of the impact ground pressure. To enhance the impact protection performance of “support and surrounding rock” system. From the perspective of preventing the resonance of the “support and surrounding rock” system, the dynamic response of energy-absorbing and anti-scouring column is studied. Using the block theory, a dynamic model of the roadway enclosure-absorbing anti-scouring column under impact loading was established, and the dynamic response equation of the rock block at the support end was obtained. Based on the structural dynamics and Love shell theory, the characteristic equations of the energy-absorbing and anti-scouring column were derived, and the theoretical equations for the natural frequency and vibration mode function of the energy-absorbing and anti-scouring column were obtained. The ABAQUS numerical simulation method was used to carry out pre-stress modal analysis and harmonious response analysis of energy-absorbing and anti-scouring columns and conventional columns. We obtained the natural frequencies and vibration modes of the two columns and analyzed the effect of the setting load on the modalities of the columns. The column dynamic response law was determined by monitoring the displacement and velocity response curves at different positions. The results show that the natural frequency and vibration mode of the energy-absorbing and anti-scouring column are related to the density, elastic modulus, and length. The vibration of the energy-absorbing and anti-scouring column has two forms: beam vibration mode and cylindrical shell vibration mode, and the first four orders of vibration mode are transverse bend. The setting load has a small effect on the natural frequency and vibration mode of both types of columns, where the natural frequency decreases as the setting load increases. When the excitation frequency is close to the vibration frequency of the surrounding rock, the radial, axial, and circumferential response amplitudes of the primary and secondary columns of the energy-absorbing and anti-scouring column are the largest. Reinforcement and strengthening measures should be implemented to reduce the column deformation amplitude
Bis(piperazine-1,4-diium) hexachloridobismuthate(III) chloride monohydrate
The crystal structure of the title compound, (C4H12N2)2[BiCl6]Cl·H2O, consists of piperazinediium cations, [BiCl6]3− anions, Cl− anions and uncoordinated water molecules. The BiIII cation is coordinated by six Cl− anions in a slightly distorted octahedral geometry. The diprotonated piperazine ring adopts a chair conformation. In the crystal, extensive intermolecular N—H⋯Cl, N—H⋯O and O—H⋯Cl hydrogen bonds occur
Heterogeneous Graph Neural Network for Privacy-Preserving Recommendation
Social networks are considered to be heterogeneous graph neural networks
(HGNNs) with deep learning technological advances. HGNNs, compared to
homogeneous data, absorb various aspects of information about individuals in
the training stage. That means more information has been covered in the
learning result, especially sensitive information. However, the
privacy-preserving methods on homogeneous graphs only preserve the same type of
node attributes or relationships, which cannot effectively work on
heterogeneous graphs due to the complexity. To address this issue, we propose a
novel heterogeneous graph neural network privacy-preserving method based on a
differential privacy mechanism named HeteDP, which provides a double guarantee
on graph features and topology. In particular, we first define a new attack
scheme to reveal privacy leakage in the heterogeneous graphs. Specifically, we
design a two-stage pipeline framework, which includes the privacy-preserving
feature encoder and the heterogeneous link reconstructor with gradients
perturbation based on differential privacy to tolerate data diversity and
against the attack. To better control the noise and promote model performance,
we utilize a bi-level optimization pattern to allocate a suitable privacy
budget for the above two modules. Our experiments on four public benchmarks
show that the HeteDP method is equipped to resist heterogeneous graph privacy
leakage with admirable model generalization
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