185 research outputs found
Greening Your Way to Profits: Green Strategies and Green Revenues
We examine hot-debated but underexplored questions of whether and how green strategies affect corporate green revenues. Using a generalized Difference-in-Differences (DiD) framework, we find that green strategies significantly enhance corporate green revenues in the presence of China's Emission Trading Scheme (ETS) pilot. This is consistent with the Porter Hypothesis. Our mechanism analyses document that green strategies increase green revenues by improving green quality and catalyzing environmentally friendly transformation. This study has important implications for policymakers and practitioners, offering new insights into the intended consequences and real outcomes of environmental regulations
Generalizing Graph ODE for Learning Complex System Dynamics across Environments
Learning multi-agent system dynamics has been extensively studied for various
real-world applications, such as molecular dynamics in biology. Most of the
existing models are built to learn single system dynamics from observed
historical data and predict the future trajectory. In practice, however, we
might observe multiple systems that are generated across different
environments, which differ in latent exogenous factors such as temperature and
gravity. One simple solution is to learn multiple environment-specific models,
but it fails to exploit the potential commonalities among the dynamics across
environments and offers poor prediction results where per-environment data is
sparse or limited. Here, we present GG-ODE (Generalized Graph Ordinary
Differential Equations), a machine learning framework for learning continuous
multi-agent system dynamics across environments. Our model learns system
dynamics using neural ordinary differential equations (ODE) parameterized by
Graph Neural Networks (GNNs) to capture the continuous interaction among
agents. We achieve the model generalization by assuming the dynamics across
different environments are governed by common physics laws that can be captured
via learning a shared ODE function. The distinct latent exogenous factors
learned for each environment are incorporated into the ODE function to account
for their differences. To improve model performance, we additionally design two
regularization losses to (1) enforce the orthogonality between the learned
initial states and exogenous factors via mutual information minimization; and
(2) reduce the temporal variance of learned exogenous factors within the same
system via contrastive learning. Experiments over various physical simulations
show that our model can accurately predict system dynamics, especially in the
long range, and can generalize well to new systems with few observations
MedChatZH: a Better Medical Adviser Learns from Better Instructions
Generative large language models (LLMs) have shown great success in various
applications, including question-answering (QA) and dialogue systems. However,
in specialized domains like traditional Chinese medical QA, these models may
perform unsatisfactorily without fine-tuning on domain-specific datasets. To
address this, we introduce MedChatZH, a dialogue model designed specifically
for traditional Chinese medical QA. Our model is pre-trained on Chinese
traditional medical books and fine-tuned with a carefully curated medical
instruction dataset. It outperforms several solid baselines on a real-world
medical dialogue dataset. We release our model, code, and dataset on
https://github.com/tyang816/MedChatZH to facilitate further research in the
domain of traditional Chinese medicine and LLMs.Comment: 7 pages, 3 figure
Determination of chlorantraniliprole and penoxsulam residues in rice by QuEChERS-UPLC-MS/MS
Objective: To establish a new QuEChERS-ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the detection of chlorantraniliprole and penoxsulam residues in rice. Methods: After the sample was extracted with 0.2% formic acid-acetonitrile, purified with N-propylethylenediamine (PSA) and graphitized carbon black (GCB) packing, 0.2% formic acid water and acetonitrile were used as mobile phases for gradient elution, and then subjected to C18 chromatography. UPLC-MS/MS was used to column separation and determination. Results: The limits of quantification (LOQ) of chlorantraniliprole and penoxsulam were both 0.004 mg/kg, and the method detection limits (LOD) were both 0.001 mg/kg. Chlorantraniliprole and penoxsulam had a good linear relationship in the range of 0.002~0.5 mg/L, and their coefficient was greater than 0.993. At the addition levels of 0.05, 0.1, and 0.5 mg/kg, the average recovery rates of chlorantraniliprole and penoxsulam were 86% to 110% with the relative standard deviations (RSD) of 1.5% to 6.1%. Conclusion: This method is efficient and simple, has good stability and high sensitivity, and is suitable for the detection of chlorantraniliprole and penoxsulam in rice
Synergistic Signals: Exploiting Co-Engagement and Semantic Links via Graph Neural Networks
Given a set of candidate entities (e.g. movie titles), the ability to
identify similar entities is a core capability of many recommender systems.
Most often this is achieved by collaborative filtering approaches, i.e. if
users co-engage with a pair of entities frequently enough, the embeddings
should be similar. However, relying on co-engagement data alone can result in
lower-quality embeddings for new and unpopular entities. We study this problem
in the context recommender systems at Netflix. We observe that there is
abundant semantic information such as genre, content maturity level, themes,
etc. that complements co-engagement signals and provides interpretability in
similarity models. To learn entity similarities from both data sources
holistically, we propose a novel graph-based approach called SemanticGNN.
SemanticGNN models entities, semantic concepts, collaborative edges, and
semantic edges within a large-scale knowledge graph and conducts representation
learning over it. Our key technical contributions are twofold: (1) we develop a
novel relation-aware attention graph neural network (GNN) to handle the
imbalanced distribution of relation types in our graph; (2) to handle web-scale
graph data that has millions of nodes and billions of edges, we develop a novel
distributed graph training paradigm. The proposed model is successfully
deployed within Netflix and empirical experiments indicate it yields up to 35%
improvement in performance on similarity judgment tasks
Causal Graph ODE: Continuous Treatment Effect Modeling in Multi-agent Dynamical Systems
Real-world multi-agent systems are often dynamic and continuous, where the
agents co-evolve and undergo changes in their trajectories and interactions
over time. For example, the COVID-19 transmission in the U.S. can be viewed as
a multi-agent system, where states act as agents and daily population movements
between them are interactions. Estimating the counterfactual outcomes in such
systems enables accurate future predictions and effective decision-making, such
as formulating COVID-19 policies. However, existing methods fail to model the
continuous dynamic effects of treatments on the outcome, especially when
multiple treatments (e.g., "stay-at-home" and "get-vaccine" policies) are
applied simultaneously. To tackle this challenge, we propose Causal Graph
Ordinary Differential Equations (CAG-ODE), a novel model that captures the
continuous interaction among agents using a Graph Neural Network (GNN) as the
ODE function. The key innovation of our model is to learn time-dependent
representations of treatments and incorporate them into the ODE function,
enabling precise predictions of potential outcomes. To mitigate confounding
bias, we further propose two domain adversarial learning-based objectives,
which enable our model to learn balanced continuous representations that are
not affected by treatments or interference. Experiments on two datasets (i.e.,
COVID-19 and tumor growth) demonstrate the superior performance of our proposed
model
TANGO: Time-Reversal Latent GraphODE for Multi-Agent Dynamical Systems
Learning complex multi-agent system dynamics from data is crucial across many
domains, such as in physical simulations and material modeling. Extended from
purely data-driven approaches, existing physics-informed approaches such as
Hamiltonian Neural Network strictly follow energy conservation law to introduce
inductive bias, making their learning more sample efficiently. However, many
real-world systems do not strictly conserve energy, such as spring systems with
frictions. Recognizing this, we turn our attention to a broader physical
principle: Time-Reversal Symmetry, which depicts that the dynamics of a system
shall remain invariant when traversed back over time. It still helps to
preserve energies for conservative systems and in the meanwhile, serves as a
strong inductive bias for non-conservative, reversible systems. To inject such
inductive bias, in this paper, we propose a simple-yet-effective
self-supervised regularization term as a soft constraint that aligns the
forward and backward trajectories predicted by a continuous graph neural
network-based ordinary differential equation (GraphODE). It effectively imposes
time-reversal symmetry to enable more accurate model predictions across a wider
range of dynamical systems under classical mechanics. In addition, we further
provide theoretical analysis to show that our regularization essentially
minimizes higher-order Taylor expansion terms during the ODE integration steps,
which enables our model to be more noise-tolerant and even applicable to
irreversible systems. Experimental results on a variety of physical systems
demonstrate the effectiveness of our proposed method. Particularly, it achieves
an MSE improvement of 11.5 % on a challenging chaotic triple-pendulum systems
Impact of ankle-foot strengthening therapy on motor function in children with cerebral palsy
Objective To investigate the changes of motor function in children with cerebral palsy undergoing ankle-foot strengthening therapy. Methods A total of 80 children with cerebral palsy were enrolled in this study,and divided into the control group(n = 40)and observation group(n = 40). In the control group,children received regular trunk training based on motor control theory combined with neurodevelopmental therapy,and those in the observation group received ankle-foot strengthening therapy in addition to those interventions in the control group. Pre-and post-treatment assessments including the Gross Motor Function Measure(GMFM-88)scores for Sections D and E,the 6-minute walk test(6-MWT),the Timed Up and Go Test(TUGT),and the Pediatric Balance Scale(PBS)were recorded to compare clinical efficacy between two groups. Results Following corresponding interventions,significant improvement was observed in all observed indexes in two groups(all P < 0.05). Notably,children in the observation group exhibited better post-treatment scores in GMFM Section E,6-MWT,TUGT,and PBS compared to their counterparts in the control group,with statistically significant differences(all P < 0.05). Conclusion Ankle-foot strengthening therapy effectively promotes the recovery of motor function in children with cerebral palsy
- …