40 research outputs found
Information-Theoretic GAN Compression with Variational Energy-based Model
We propose an information-theoretic knowledge distillation approach for the
compression of generative adversarial networks, which aims to maximize the
mutual information between teacher and student networks via a variational
optimization based on an energy-based model. Because the direct computation of
the mutual information in continuous domains is intractable, our approach
alternatively optimizes the student network by maximizing the variational lower
bound of the mutual information. To achieve a tight lower bound, we introduce
an energy-based model relying on a deep neural network to represent a flexible
variational distribution that deals with high-dimensional images and consider
spatial dependencies between pixels, effectively. Since the proposed method is
a generic optimization algorithm, it can be conveniently incorporated into
arbitrary generative adversarial networks and even dense prediction networks,
e.g., image enhancement models. We demonstrate that the proposed algorithm
achieves outstanding performance in model compression of generative adversarial
networks consistently when combined with several existing models.Comment: Accepted at Neurips202
Design of a Compact Indirect Slot-Fed Wideband Patch Array with an Air SIW Cavity for a High Directivity in Missile Seeker Applications
This research proposes a compact indirect slot-fed wideband patch array antenna for a missile seeker application. The proposed single antenna consists of three dielectric layers for a radiator, an air substrate-integrated waveguide (SIW) cavity, and an indirect feeding network. The rectangular patch is used as a radiator on the first substrate layer, and the air SIW cavity (ASIWC) is employed to obtain high directivity and low mutual coupling characteristics in the second substrate layer. In the third layer, an indirect feeding structure is used to achieve the wideband characteristics in the Ka-band. The single element is extended to a 4 x 1 linear array with fabrication, and the fabricated array characteristics are measured in a full anechoic chamber. The measured operating fractional frequency bandwidth is 9.2%, and the measured array gain is 11.7 dBi at the bore-sight direction (theta(0) = 0 degrees)
Silver-Enhanced In Situ Hybridization as an Alternative to Fluorescence In Situ Hybridization for Assaying HER2 Amplification in Clinical Breast Cancer
Purpose: Valid determination of HER2 status is a prerequisite to establish an adequate treatment strategy for breast cancer patients, regardless of the disease stage. The goal of this study was to examine the feasibility of the newly developed silver-enhanced in situ hybridization (SISH) technique as an alternative to fluorescence in situ hybridization (FISH) for HER2 assay in primary invasive breast cancer. Methods: FISH and SISH for HER2 amplification were performed using tissue microarray. Both methods were used in 257 consecutive primary breast cancers. Results: HER2 amplification was observed in 62 (23.1%) of a total of 257 breast cancers based on SISH. Of the 257 breast cancers measured using both methods, the results of the two methods were consistent in 248 (concordance, 96.5%; kappa=0.903). When we compared HER2 amplification in the primary tumor with the metastatic lymph nodes of the same patients, HER2 amplification was observed in nine cases (14.0%) out of 64 cases in which HER2 was not amplified in the primary tumors. In contrast, HER2 status was completely preserved in metastatic lymph nodes showing HER2 amplification in the primary tumor. Conclusion: These results indicate that SISH can be a feasible alternative to FISH in the clinical setting. In node-positive breast cancer, confirmation of the HER2 status of the metastatic lymph nodes appears to be mandatory, regardless of the HER2 status of the primary tumors. Key Words: Breast neoplasms, HER2, In situ hybridizatio
Comparison of Doxorubicin Plus Docetaxel Neoadjuvant Chemotherapy with Doxorubicin Plus Vinorelbine in Primary Breast Cancer
Purpose: This study was performed to compare the therapeutic efficacy and toxicity of doxorubicin plus docetaxel neoadjuvant chemotherapy (NC) with doxorubicin plus vinorelbine NC. Methods: Fifty-three patients underwent 4 cycles of NC consisted of intravenous injection of doxorubicin (50 mg/m 2) plus docetaxel (75 mg/m 2) administered every 3 weeks (AD), while 49 patients underwent 4 cycles of NC consisted of intravenous injection of doxorubicin (50 mg/m 2) and vinorelbine (25 mg/m 2) administered every 3 weeks (AN). Response rate and treatment-related toxicities were analyzed by administered chemotherapeutics. Response to NC was also analyzed according to clinicobiological characteristics of the primary tumors. Results: Clinical response was observed in 66 % with AN and 81.6 % with AD chemotherapy. A complete pathologic response (pCR) was confirmed in 6 patients (11.3%) with AN and in 7 patients (14.3%) with AD afte
Propagation Control of Octahedral Tilt in SrRuO(3)via Artificial Heterostructuring
Bonding geometry engineering of metal-oxygen octahedra is a facile way of tailoring various functional properties of transition metal oxides. Several approaches, including epitaxial strain, thickness, and stoichiometry control, have been proposed to efficiently tune the rotation and tilt of the octahedra, but these approaches are inevitably accompanied by unnecessary structural modifications such as changes in thin-film lattice parameters. In this study, a method to selectively engineer the octahedral bonding geometries is proposed, while maintaining other parameters that might implicitly influence the functional properties. A concept of octahedral tilt propagation engineering is developed using atomically designed SrRuO3/SrTiO3(SRO/STO) superlattices. In particular, the propagation of RuO(6)octahedral tilt within the SRO layers having identical thicknesses is systematically controlled by varying the thickness of adjacent STO layers. This leads to a substantial modification in the electromagnetic properties of the SRO layer, significantly enhancing the magnetic moment of Ru. This approach provides a method to selectively manipulate the bonding geometry of strongly correlated oxides, thereby enabling a better understanding and greater controllability of their functional properties
Phase II randomized trial of neoadjuvant metformin plus letrozole versus placebo plus letrozole for estrogen receptor positive postmenopausal breast cancer (METEOR)
This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.Abstract
Background
Neoadjuvant endocrine therapy with an aromatase inhibitor has shown efficacy comparable to that of neoadjuvant chemotherapy in patients with postmenopausal breast cancer. Preclinical and clinical studies have shown that the antidiabetic drug metformin has anti-tumor activity. This prospective, multicenter, phase II randomized, placebo controlled trial was designed to evaluate the direct anti-tumor effect of metformin in non-diabetic postmenopausal women with estrogen-receptor (ER) positive breast cancer.
Methods/Design
Patients meeting the inclusion criteria and providing written informed consent will be randomized to 24ย weeks of neoadjuvant treatment with letrozole (2.5ย mg/day) and either metformin (2000ย mg/day) or placebo. Target accrual number is 104 patients per arm. The primary endpoint will be clinical response rate, as measured by calipers. Secondary endpoints include pathologic complete response rate, breast conserving rate, change in Ki67 expression, breast density change, and toxicity profile. Molecular assays will be performed using samples obtained before treatment, at week 4, and postoperatively.
Discussion
This study will provide direct evidence of the anti-tumor effect of metformin in non-diabetic, postmenopausal patients with ER-positive breast cancer.
Trial registration
ClinicalTrials.gov Identifier
NCT0158936
Phase II randomized trial of neoadjuvant metformin plus letrozole versus placebo plus letrozole for estrogen receptor positive postmenopausal breast cancer (METEOR)
This study is being supported by grant no 04-2012-0290 from the SNUH Research fund and by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIP)(No. 2013005540).
Letrozole and metformin are being supplied by the pharmaceutical company, Shin Poong Pharm. Co., Ltd.Background : Neoadjuvant endocrine therapy with an aromatase inhibitor has shown efficacy comparable to that of neoadjuvant chemotherapy in patients with postmenopausal breast cancer. Preclinical and clinical studies have shown that the antidiabetic drug metformin has anti-tumor activity. This prospective, multicenter, phase II randomized, placebo controlled trial was designed to evaluate the direct anti-tumor effect of metformin in non-diabetic postmenopausal women with estrogen-receptor (ER) positive breast cancer.
Methods/Design : Patients meeting the inclusion criteria and providing written informed consent will be randomized to 24ย weeks of neoadjuvant treatment with letrozole (2.5ย mg/day) and either metformin (2000ย mg/day) or placebo. Target accrual number is 104 patients per arm. The primary endpoint will be clinical response rate, as measured by calipers. Secondary endpoints include pathologic complete response rate, breast conserving rate, change in Ki67 expression, breast density change, and toxicity profile. Molecular assays will be performed using samples obtained before treatment, at week 4, and postoperatively.
Discussion : This study will provide direct evidence of the anti-tumor effect of metformin in non-diabetic, postmenopausal patients with ER-positive breast cancer.
Trial registration : ClinicalTrials.gov Identifier NCT01589367Peer Reviewe
Locally enhanced lightโmatter interaction of MoS2 monolayers at density-controllable nanogrooves of template-stripped Ag films
ยฉ 2021Transition metal dichalcogenide (TMD) monolayers, such as MoS2, possess a direct optical bandgap are useful for emerging ultrathin optoelectronics in the visible light range, whereas their thin thickness limits light absorption and emission properties. To address this drawback, one promising approach is to hybridize plasmonic nanostructures with monolayer TMDs to utilize local field enhancement effects owing to localized surface plasmon resonance (LSPR). Herein, we propose a strong enhancement of the local lightโmatter interaction in MoS2 monolayers on naturally generated nanoscale grooves. The nanogrooves are formed at grain boundaries (GBs) of template-stripped metal film substrates that are fabricated by mechanically stripping Ag films deposited on an ultra-flat Si substrate, wherein the nanogroove densities are systematically modulated by the Ag film thickness. We observe an effective photoluminescence enhancement factor of 758 and a Raman spectroscopy intensity enhancement of approximately 5 times in MoS2 on the subwavelength-scale nanogrooves, compared with that on grain planes, which is attributed to a strong local field enhancement of the LSPR effect. Moreover, this plasmonic enhancement effect is elucidated by dark-field scattering spectroscopy and optical simulations. Our results can facilitate the utilization of density-controllable plasmonic nanogrooves synthesized without nanopatterning techniques for plasmonic hybrids on 2D semiconductors.11Nscopu