404 research outputs found
How Does Suppliers’ Fairness Affect the Relationship Quality of Agricultural Product Supply Chains?
Although many studies have suggested that the relationship between different supply chain members significantly affects agricultural product quality, suppliers’ perceptions of fairness, which greatly influence their decisions on building the relationship quality, are often overlooked. Particularly, the empirical evidence to investigate the impacts of suppliers’ fairness on the relationship quality and the factors that affect the suppliers’ fairness is missing, and therefore this knowledge gap needs to be filled by new research. Herein, we conducted a survey of 450 agricultural product suppliers and systemically analyzed the impact of antecedents on fairness perception and the impact of fairness perception on relationship quality. In addition, we developed a structural equation model and found that information sharing and price satisfaction had significantly positive effects on procedural fairness and distributive fairness, respectively. Furthermore, our studies demonstrated that procedural fairness is more important in improving the relationship quality than distributive fairness. However, supplier dependence is another important impact factor, and it greatly decreases the positive effects of suppliers’ fairness on relationship quality. In summary, the study results provide several managerial implications and extend our understanding of the importance of suppliers’ fairness in the relationship quality, which involves product development with respect to the supplier’s performance
An Information Minimization Based Contrastive Learning Model for Unsupervised Sentence Embeddings Learning
Unsupervised sentence embeddings learning has been recently dominated by
contrastive learning methods (e.g., SimCSE), which keep positive pairs similar
and push negative pairs apart. The contrast operation aims to keep as much
information as possible by maximizing the mutual information between positive
instances, which leads to redundant information in sentence embedding. To
address this problem, we present an information minimization based contrastive
learning (InforMin-CL) model to retain the useful information and discard the
redundant information by maximizing the mutual information and minimizing the
information entropy between positive instances meanwhile for unsupervised
sentence representation learning. Specifically, we find that information
minimization can be achieved by simple contrast and reconstruction objectives.
The reconstruction operation reconstitutes the positive instance via the other
positive instance to minimize the information entropy between positive
instances. We evaluate our model on fourteen downstream tasks, including both
supervised and unsupervised (semantic textual similarity) tasks. Extensive
experimental results show that our InforMin-CL obtains a state-of-the-art
performance.Comment: 11 pages, 3 figures, published to COLING 202
Directional diffusion models for graph representation learning
In recent years, diffusion models have achieved remarkable success in various
domains of artificial intelligence, such as image synthesis, super-resolution,
and 3D molecule generation. However, the application of diffusion models in
graph learning has received relatively little attention. In this paper, we
address this gap by investigating the use of diffusion models for unsupervised
graph representation learning. We begin by identifying the anisotropic
structures of graphs and a crucial limitation of the vanilla forward diffusion
process in learning anisotropic structures. This process relies on continuously
adding an isotropic Gaussian noise to the data, which may convert the
anisotropic signals to noise too quickly. This rapid conversion hampers the
training of denoising neural networks and impedes the acquisition of
semantically meaningful representations in the reverse process. To address this
challenge, we propose a new class of models called {\it directional diffusion
models}. These models incorporate data-dependent, anisotropic, and directional
noises in the forward diffusion process. To assess the efficacy of our proposed
models, we conduct extensive experiments on 12 publicly available datasets,
focusing on two distinct graph representation learning tasks. The experimental
results demonstrate the superiority of our models over state-of-the-art
baselines, indicating their effectiveness in capturing meaningful graph
representations. Our studies not only provide valuable insights into the
forward process of diffusion models but also highlight the wide-ranging
potential of these models for various graph-related tasks
MetaViewer: Towards A Unified Multi-View Representation
Existing multi-view representation learning methods typically follow a
specific-to-uniform pipeline, extracting latent features from each view and
then fusing or aligning them to obtain the unified object representation.
However, the manually pre-specify fusion functions and view-private redundant
information mixed in features potentially degrade the quality of the derived
representation. To overcome them, we propose a novel
bi-level-optimization-based multi-view learning framework, where the
representation is learned in a uniform-to-specific manner. Specifically, we
train a meta-learner, namely MetaViewer, to learn fusion and model the
view-shared meta representation in outer-level optimization. Start with this
meta representation, view-specific base-learners are then required to rapidly
reconstruct the corresponding view in inner-level. MetaViewer eventually
updates by observing reconstruction processes from uniform to specific over all
views, and learns an optimal fusion scheme that separates and filters out
view-private information. Extensive experimental results in downstream tasks
such as classification and clustering demonstrate the effectiveness of our
method.Comment: 8 pages, 5 figures, conferenc
Guanxintai Exerts Protective Effects on Ischemic Cardiomyocytes by Mitigating Oxidative Stress
Oxidative stress participates in numerous myocardial pathophysiological processes and is considered a therapeutic target for myocardial ischemia and heart failure. Guanxintai (GXT), a traditional Chinese medicine, is commonly used to treat cardiovascular disease on account of its numerous beneficial physiological activities, such as dilating coronary arteries, inhibiting platelet aggregation, and reducing the serum lipid content. However, the antioxidative properties of GXT and potential underlying mechanisms remain to be established. In the present study, we investigated the protective effects of GXT on ischemic cardiomyocytes and the associated antioxidative mechanisms, both in vivo and in vitro. Notably, GXT treatment reduced the degree of cardiomyocyte injury, myocardial apoptosis, and fibrosis and partially improved cardiac function after myocardial infarction. Furthermore, GXT suppressed the level of ROS as well as expression of NADPH oxidase (NOX) and phospho-p38 mitogen-activated protein kinase (MAPK) proteins. Our results collectively suggest that the protective effects of GXT on ischemic cardiomyocytes are exerted through its antioxidative activity of NOX inhibition
Mechanisms of Ferroptosis and Relations With Regulated Cell Death: A Review
Ferroptosis is a newly identified form of nonapoptotic regulated cell death (RCD) characterized by iron-dependent accumulation of lipid peroxides. It is morphologically and biochemically different from known types of cell death. Ferroptosis plays a vital role in the treatment of tumors, renal failure, and ischemia reperfusion injury (IRI). Inhibition of glutathione peroxidase 4 (GPX4), starvation of cysteine, and peroxidation of arachidonoyl (AA) trigger ferroptosis in the cells. Iron chelators, lipophilic antioxidants, and specific inhibitor prevent ferroptosis. Although massive researches have demonstrated the importance of ferroptosis in human, its mechanism is not really clear. In this review, we distanced ourselves from this confusion by dividing the mechanisms of ferroptosis into two aspects: processes that facilitate the formation of lipid peroxides and processes that suppress the reduction of lipid peroxides. At the same time, we summarize the relations between ferroptosis and several types of cell death
Study on the Effect of Nano-SiO 2
Both process and mechanical of silicon substrate chemical mechanical polishing (CMP) are studied in detail, and the effects of experiments designed indicate that nano-SiO2 grinding particles seem to be acted as catalyzer besides the grinding action during the CMP process. This is different from the traditional function. As a result, in the condition of low pH, the nano-SiO2 slurry can be recycled. In the meanwhile, the removal rate can gain stability and pH value does not change obviously
A Survey of Source Code Search: A 3-Dimensional Perspective
(Source) code search is widely concerned by software engineering researchers
because it can improve the productivity and quality of software development.
Given a functionality requirement usually described in a natural language
sentence, a code search system can retrieve code snippets that satisfy the
requirement from a large-scale code corpus, e.g., GitHub. To realize effective
and efficient code search, many techniques have been proposed successively.
These techniques improve code search performance mainly by optimizing three
core components, including query understanding component, code understanding
component, and query-code matching component. In this paper, we provide a
3-dimensional perspective survey for code search. Specifically, we categorize
existing code search studies into query-end optimization techniques, code-end
optimization techniques, and match-end optimization techniques according to the
specific components they optimize. Considering that each end can be optimized
independently and contributes to the code search performance, we treat each end
as a dimension. Therefore, this survey is 3-dimensional in nature, and it
provides a comprehensive summary of each dimension in detail. To understand the
research trends of the three dimensions in existing code search studies, we
systematically review 68 relevant literatures. Different from existing code
search surveys that only focus on the query end or code end or introduce
various aspects shallowly (including codebase, evaluation metrics, modeling
technique, etc.), our survey provides a more nuanced analysis and review of the
evolution and development of the underlying techniques used in the three ends.
Based on a systematic review and summary of existing work, we outline several
open challenges and opportunities at the three ends that remain to be addressed
in future work.Comment: submitted to ACM Transactions on Software Engineering and Methodolog
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