640 research outputs found
Smoothness of the Value Function for Optimal Consumption Model with Consumption-Wealth Utility and Borrowing Constraint
This paper studies an optimal consumption-investment problem for an investor
whose instantaneous utility depends on both consumption and wealth, and the
investor faces a general borrowing constraint that the investment amount in the
risky asset does not exceed an exogenous function of the wealth. We show that
the value function is second-order smooth and present the optimal
consumption-investment policy in a feedback form. Moreover, when the risky
investment amount is bounded above by a fixed constant, we show that under
certain conditions, the constraint is binding if and only if an endogenous
threshold bounds the portfolio wealth, and we determine the endogenous wealth
threshold with the smooth fit condition. Our results encompass several
well-developed portfolio choice models and imply new applications.Comment: 35 page
Epigenetic features are significantly associated with alternative splicing
<p>Abstract</p> <p>Background</p> <p>While alternative splicing (AS) contributes greatly to protein diversities, the relationship between various types of AS and epigenetic factors remains largely unknown.</p> <p>Results</p> <p>In this study, we discover that a number of epigenetic features, including DNA methylation, nucleosome occupancy, specific histone modifications and protein features, are strongly associated with AS. To further enhance our understanding of the association between these features and AS, we cluster our investigated features based on their association patterns with each AS type into four groups, with H3K36me3, EGR1, GABP, SRF, SIN3A and RNA Pol II grouped together and showing strongest association with AS. In addition, we find that the AS types can be classified into two general classes, namely the exon skipping related process (ESRP), and the alternative splice site selection process (ASSP), based on their association levels with the epigenetic features.</p> <p>Conclusion</p> <p>Our analysis thus suggests that epigenetic features are likely to play important roles in regulating AS.</p
A Novel Method of Sentence Ordering Based on Support Vector Machine
PACLIC 23 / City University of Hong Kong / 3-5 December 200
Improving Image Captioning via Predicting Structured Concepts
Having the difficulty of solving the semantic gap between images and texts
for the image captioning task, conventional studies in this area paid some
attention to treating semantic concepts as a bridge between the two modalities
and improved captioning performance accordingly. Although promising results on
concept prediction were obtained, the aforementioned studies normally ignore
the relationship among concepts, which relies on not only objects in the image,
but also word dependencies in the text, so that offers a considerable potential
for improving the process of generating good descriptions. In this paper, we
propose a structured concept predictor (SCP) to predict concepts and their
structures, then we integrate them into captioning, so as to enhance the
contribution of visual signals in this task via concepts and further use their
relations to distinguish cross-modal semantics for better description
generation. Particularly, we design weighted graph convolutional networks
(W-GCN) to depict concept relations driven by word dependencies, and then
learns differentiated contributions from these concepts for following decoding
process. Therefore, our approach captures potential relations among concepts
and discriminatively learns different concepts, so that effectively facilitates
image captioning with inherited information across modalities. Extensive
experiments and their results demonstrate the effectiveness of our approach as
well as each proposed module in this work.Comment: Accepted by EMNLP 2023 (Main Conference, Oral
Single-cell RNA-seq reveals developmental deficiencies in both the placentation and the decidualization in women with late-onset preeclampsia
Preeclampsia (PE) is a leading cause of maternal and fetal morbidity and mortality. Although increasing lines of evidence suggest that both the placenta and the decidua likely play roles in the pathogenesis of PE, the molecular mechanism of PE remains elusive partly because of the heterogeneity nature of the maternal-fetal interface. In this study, we perform single-cell RNA-seq on the placenta and the decidual from patients with late-onset PE (LOPE) and women in normal pregnancy. Analyses of single-cell transcriptomes reveal that in LOPE, there are likely a global development deficiency of trophoblasts with impaired invasion of extravillous trophoblasts (EVT) and increased maternal immune rejection and inflammation in the placenta, while there are likely insufficient decidualization of decidual stromal cells (DSC), increased inflammation, and suppressed regulatory functions of decidual immune cells. These findings improve our understanding of the molecular mechanisms of PE
Water pollutant fingerprinting tracks recent industrial transfer from coastal to inland China: a case study
In recent years, China’s developed regions have transferred industries to undeveloped regions. Large numbers of unlicensed or unregistered enterprises are widespread in these undeveloped regions and they are subject to minimal regulation. Current methods for tracing industrial transfers in these areas, based on
enterprise registration information or economic surveys, do not work. The authors have developed an analytical framework combining water fingerprinting and evolutionary analysis to trace the pollution transfer features between water sources. We collected samples in Eastern China (industrial export) and Central China
(industrial acceptance) separately from two water systems. Based on the water pollutant fingerprints and evolutionary trees, we traced the pollution transfer associated with industrial transfer between the two areas. The results are consistent with four episodes of industrial transfers over the past decade. The results also
show likely types of the transferred industries - electronics, plastics, and biomedicines - that contribute to the water pollution transfer
Few-shot image classification : current status and research trends
Conventional image classification methods usually require a large number of training samples for the training model. However, in practical scenarios, the amount of available sample data is often insufficient, which easily leads to overfitting in network construction. Few-shot learning provides an effective solution to this problem and has been a hot research topic. This paper provides an intensive survey on the state-of-the-art techniques in image classification based on few-shot learning. According to the different deep learning mechanisms, the existing algorithms are di-vided into four categories: transfer learning based, meta-learning based, data augmentation based, and multimodal based methods. Transfer learning based methods transfer useful prior knowledge from the source domain to the target domain. Meta-learning based methods employ past prior knowledge to guide the learning of new tasks. Data augmentation based methods expand the amount of sample data with auxiliary information. Multimodal based methods use the information of the auxiliary modal to facilitate the implementation of image classification tasks. This paper also summarizes the few-shot image datasets available in the literature, and experimental results tested by some representative algorithms are provided to compare their performance and analyze their pros and cons. In addition, the application of existing research outcomes on few-shot image classification in different practical fields are discussed. Finally, a few future research directions are iden-tified. © 2022 by the authors. Licensee MDPI, Basel, Switzerland
Analysis of corrections to the eikonal approximation
Various corrections to the eikonal approximations are studied for two- and
three-body nuclear collisions with the goal to extend the range of validity of
this approximation to beam energies of 10 MeV/nucleon. Wallace's correction
does not improve much the elastic-scattering cross sections obtained at the
usual eikonal approximation. On the contrary, a semiclassical approximation
that substitutes the impact parameter by a complex distance of closest approach
computed with the projectile-target optical potential efficiently corrects the
eikonal approximation. This opens the possibility to analyze data measured down
to 10 MeV/nucleon within eikonal-like reaction models.Comment: 10 pages, 8 figure
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