64 research outputs found
Federated Learning for Sparse Principal Component Analysis
In the rapidly evolving realm of machine learning, algorithm effectiveness
often faces limitations due to data quality and availability. Traditional
approaches grapple with data sharing due to legal and privacy concerns. The
federated learning framework addresses this challenge. Federated learning is a
decentralized approach where model training occurs on client sides, preserving
privacy by keeping data localized. Instead of sending raw data to a central
server, only model updates are exchanged, enhancing data security. We apply
this framework to Sparse Principal Component Analysis (SPCA) in this work. SPCA
aims to attain sparse component loadings while maximizing data variance for
improved interpretability. Beside the L1 norm regularization term in
conventional SPCA, we add a smoothing function to facilitate gradient-based
optimization methods. Moreover, in order to improve computational efficiency,
we introduce a least squares approximation to original SPCA. This enables
analytic solutions on the optimization processes, leading to substantial
computational improvements. Within the federated framework, we formulate SPCA
as a consensus optimization problem, which can be solved using the Alternating
Direction Method of Multipliers (ADMM). Our extensive experiments involve both
IID and non-IID random features across various data owners. Results on
synthetic and public datasets affirm the efficacy of our federated SPCA
approach.Comment: 11 pages, 7 figures, 1 table. Accepted by IEEE BigData 2023,
Sorrento, Ital
The preprophase band-associated kinesin-14 OsKCH2 is a processive minus-end-directed microtubule motor.
In animals and fungi, cytoplasmic dynein is a processive minus-end-directed motor that plays dominant roles in various intracellular processes. In contrast, land plants lack cytoplasmic dynein but contain many minus-end-directed kinesin-14s. No plant kinesin-14 is known to produce processive motility as a homodimer. OsKCH2 is a plant-specific kinesin-14 with an N-terminal actin-binding domain and a central motor domain flanked by two predicted coiled-coils (CC1 and CC2). Here, we show that OsKCH2 specifically decorates preprophase band microtubules in vivo and transports actin filaments along microtubules in vitro. Importantly, OsKCH2 exhibits processive minus-end-directed motility on single microtubules as individual homodimers. We find that CC1, but not CC2, forms the coiled-coil to enable OsKCH2 dimerization. Instead, our results reveal that removing CC2 renders OsKCH2 a nonprocessive motor. Collectively, these results show that land plants have evolved unconventional kinesin-14 homodimers with inherent minus-end-directed processivity that may function to compensate for the loss of cytoplasmic dynein
Enhanced Differentiation of Three-Gene-Reprogrammed Induced Pluripotent Stem Cells into Adipocytes via Adenoviral-Mediated PGC-1α Overexpression
Induced pluripotent stem cells formed by the introduction of only three factors, Oct4/Sox2/Klf4 (3-gene iPSCs), may provide a safer option for stem cell-based therapy than iPSCs conventionally introduced with four-gene iPSCs. Peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) plays an important role during brown fat development. However, the potential roles of PGC-1α in regulating mitochondrial biogenesis and the differentiation of iPSCs are still unclear. Here, we investigated the effects of adenovirus-mediated PGC-1α overexpression in 3-gene iPSCs. PGC-1α overexpression resulted in increased mitochondrial mass, reactive oxygen species production, and oxygen consumption. Microarray-based bioinformatics showed that the gene expression pattern of PGC-1α-overexpressing 3-gene iPSCs resembled the expression pattern observed in adipocytes. Furthermore, PGC-1α overexpression enhanced adipogenic differentiation and the expression of several brown fat markers, including uncoupling protein-1, cytochrome C, and nuclear respiratory factor-1, whereas it inhibited the expression of the white fat marker uncoupling protein-2. Furthermore, PGC-1α overexpression significantly suppressed osteogenic differentiation. These data demonstrate that PGC-1α directs the differentiation of 3-gene iPSCs into adipocyte-like cells with features of brown fat cells. This may provide a therapeutic strategy for the treatment of mitochondrial disorders and obesity
The Atacama Large Millimeter/submillimeter Array (ALMA) Band-1 Receiver
The Atacama Large Millimeter/submillimeter Array(ALMA) Band 1 receiver covers
the 35-50 GHz frequency band. Development of prototype receivers, including the
key components and subsystems has been completed and two sets of prototype
receivers were fully tested. We will provide an overview of the ALMA Band 1
science goals, and its requirements and design for use on the ALMA. The
receiver development status will also be discussed and the infrastructure,
integration, evaluation of fully-assembled band 1 receiver system will be
covered. Finally, a discussion of the technical and management challenges
encountered will be presented
Risk factors and their interaction on chronic kidney disease: A multi-centre case control study in Taiwan
An Integrated Assessment Framework of Offshore Wind Power Projects Applying Equator Principles and Social Life Cycle Assessment
This paper reviews offshore wind power project finance and provides an integrated assessment that employs Equator Principles, life cycle assessment, risk assessment, materiality analysis, credit assessment, and ISAE 3000 assurance. We have not seen any comprehensive review papers or book chapters that covers the entire offshore wind power project finance process. We also conducted an SWancor Formosa Phase 1 case study to illustrate the application of integrated assessment to better assist policymakers, wind farm developers, practitioners, potential investors and observers, and stakeholders in their decisions. We believe that this paper can form part of the effort to reduce information asymmetry and the transaction costs of wind power project finance, as well as mobilize green finance investments from the financial sector to renewable energy projects to achieve a national renewable energy policy
Enhanced Compressive Downlink CSI Recovery for FDD Massive MIMO Systems Using Weighted Block -Minimization
- …