2,385 research outputs found
Low-energy excitations of the one-dimensional half-filled SU(4) Hubbard model with an attractive on-site interaction: Density-matrix renormalization-group calculations and perturbation theory
We investigate low-energy excitations of the one-dimensional half-filled
SU(4) Hubbard model with an attractive on-site interaction U < 0 using the
density matrix renormalization group method as well as a perturbation theory.
We find that the ground state is a charge density wave state with a long range
order. The ground state is completely incompressible since all the excitations
are gapful. The charge gap which is the same as the four-particle excitation
gap is a non-monotonic function of U, while the spin gap and others increase
with increasing |U| and have linear asymptotic behaviors.Comment: 4 pages, 3 figures, submitte
Gaucher disease and the synucleinopathies: refining the relationship
Gaucher disease (OMIM 230800, 230900, 231000), the most common lysosomal storage disorder, is due to a deficiency in the enzyme glucocerebrosidase. Gaucher patients display a wide spectrum of clinical presentation, with hepatosplenomegaly, haematological changes, and orthopaedic complications being the predominant symptoms. Gaucher disease is classified into three broad phenotypes based upon the presence or absence of neurological involvement: Type 1 (non-neuronopathic), Type 2 (acute neuronopathic), and Type 3 (subacute neuronopathic). Nearly 300 mutations have been identified in Gaucher patients, with the majority being missense mutations. Though studies of genotype-to-phenotype correlations have revealed significant heterogeneity, some consistent patterns have emerged to inform prognostic and therapeutic decisions. Recent research has highlighted a potential role for Gaucher disease in other comorbidities such as cancer and Parkinson's Disease. In this review, we will examine the potential relationship between Gaucher disease and the synucleinopathies, a group of neurodegenerative disorders characterized by the development of intracellular aggregates of α-synuclein. Possible mechanisms of interaction will be discussed
Gaucher Disease and Cancer: Concept and Controversy
Gaucher disease is an inherited disorder caused by a deficiency in the lysosomal hydrolase glucocerebrosidase. There is a wide spectrum of clinical presentations, with the most common features being hepatosplenomegaly, skeletal disease, and cytopenia. Gaucher disease has been classified into three broad phenotypes based upon the presence or absence of neurological involvement: Type 1 (nonneuronopathic), Type 2 (acute neuronopathic), and Type 3 (subacute neuronopathic). The two main treatment options include enzyme replacement therapy and substrate reduction therapy. Recently, discussion has escalated around the association of Gaucher disease and cancer, with conflicting reports as to whether Gaucher patients have an increased risk of malignancy. In this review, we present both the concept and controversy surrounding the association of Gaucher disease with cancer
Few-Shot Single-View 3-D Object Reconstruction with Compositional Priors
The impressive performance of deep convolutional neural networks in
single-view 3D reconstruction suggests that these models perform non-trivial
reasoning about the 3D structure of the output space. However, recent work has
challenged this belief, showing that complex encoder-decoder architectures
perform similarly to nearest-neighbor baselines or simple linear decoder models
that exploit large amounts of per category data in standard benchmarks. On the
other hand settings where 3D shape must be inferred for new categories with few
examples are more natural and require models that generalize about shapes. In
this work we demonstrate experimentally that naive baselines do not apply when
the goal is to learn to reconstruct novel objects using very few examples, and
that in a \emph{few-shot} learning setting, the network must learn concepts
that can be applied to new categories, avoiding rote memorization. To address
deficiencies in existing approaches to this problem, we propose three
approaches that efficiently integrate a class prior into a 3D reconstruction
model, allowing to account for intra-class variability and imposing an implicit
compositional structure that the model should learn. Experiments on the popular
ShapeNet database demonstrate that our method significantly outperform existing
baselines on this task in the few-shot setting
A robust computational algorithm for inverse photomask synthesis in optical projection lithography
Inverse lithography technology formulates the photomask synthesis as an inverse mathematical problem. To solve this, we propose a variational functional and develop a robust computational algorithm, where the proposed functional takes into account the process variations and incorporates several regularization terms that can control the mask complexity. We establish the existence of the minimizer of the functional, and in order to optimize it effectively, we adopt an alternating minimization procedure with Chambolle's fast duality projection algorithm. Experimental results show that our proposed algorithm is effective in synthesizing high quality photomasks as compared with existing methods.published_or_final_versio
Microstructure and electric properties of lead lanthanum titanate thin film under transverse electric fields
Author name used in this publication: N. Chong2001-2002 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Epitaxial growth and planar dielectric properties of compositionally graded (Ba[sub 1-x]Sr[sub x])TiO₃ thin films prepared by pulsed-laser deposition
2001-2002 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Discrete Point Flow Networks for Efficient Point Cloud Generation
Generative models have proven effective at modeling 3D shapes and their
statistical variations. In this paper we investigate their application to point
clouds, a 3D shape representation widely used in computer vision for which,
however, only few generative models have yet been proposed. We introduce a
latent variable model that builds on normalizing flows with affine coupling
layers to generate 3D point clouds of an arbitrary size given a latent shape
representation. To evaluate its benefits for shape modeling we apply this model
for generation, autoencoding, and single-view shape reconstruction tasks. We
improve over recent GAN-based models in terms of most metrics that assess
generation and autoencoding. Compared to recent work based on continuous flows,
our model offers a significant speedup in both training and inference times for
similar or better performance. For single-view shape reconstruction we also
obtain results on par with state-of-the-art voxel, point cloud, and mesh-based
methods.Comment: In ECCV'2
Scaling on hysteresis dispersion in ferroelectric systems
Author name used in this publication: Z. G. LiuAuthor name used in this publication: N. B. MingAuthor name used in this publication: H. L. W. ChanAuthor name used in this publication: C. L. Choy2000-2001 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Post-Retrocommissioning HVAC Operations Monitoring Using Enterprise-Wide energy Management System
Since 2004, the County of Los Angeles have retrocommissioned over 4 million square feet and additional RCx work is underway. The scope of the HVAC retrocommissioning (RCs) involved systematic investigation of mechanical, electrical and controls components/systems to diagnose and resolve root causes of operational deficiencies. During the implementation phase, new energy efficiency measures were installed, sequence of operations were optimized and functionally tested. System-level benchmark models for HVAC systems were developed based on optimized runs of eQUEST energy models and parametrically integrated into the County owned web-based Enterprise Energy Management Information Systems (EEMIS) with Itron/Silicon Energy EEM Suite backbone for the purpose of monitoring the operations of the HVAC systems. The paper and presentation describes the HVAC RCx process to optimize operations, cost and savings associated with this project and key operational changes to sustain optimized operations without sacrificing tenant comfort
- …