880 research outputs found
GaIA: Graphical Information Gain based Attention Network for Weakly Supervised Point Cloud Semantic Segmentation
While point cloud semantic segmentation is a significant task in 3D scene
understanding, this task demands a time-consuming process of fully annotating
labels. To address this problem, recent studies adopt a weakly supervised
learning approach under the sparse annotation. Different from the existing
studies, this study aims to reduce the epistemic uncertainty measured by the
entropy for a precise semantic segmentation. We propose the graphical
information gain based attention network called GaIA, which alleviates the
entropy of each point based on the reliable information. The graphical
information gain discriminates the reliable point by employing relative entropy
between target point and its neighborhoods. We further introduce anchor-based
additive angular margin loss, ArcPoint. The ArcPoint optimizes the unlabeled
points containing high entropy towards semantically similar classes of the
labeled points on hypersphere space. Experimental results on S3DIS and
ScanNet-v2 datasets demonstrate our framework outperforms the existing weakly
supervised methods. We have released GaIA at https://github.com/Karel911/GaIA.Comment: WACV 2023 accepted pape
Gasification of Municipal Solid Waste
Gasification of municipal solid waste (MSW) is an attractive alternative fuel production process for the treatment of solid waste as it has several potential benefits over traditional combustion of MSW. Syngas produced from the gasification of MSW can be utilized as a gas fuel being combusted in a conventional burner or in a gas engine to utilize the heat or produce electricity. Also, it can be used as a building block for producing valuable products such as chemicals and other forms of fuel energy. This book chapter covers the properties of MSW, gasification mechanism, chemistry, operating conditions, gasification technologies, processes, recovery system, and most importantly by reviewing the environmental impacts of MSW gasification. As one of recent advanced technologies, a case study of pilot-scale MSW gasification is introduced, which could be one of the most efficient pathways to utilize the technology to produce electricity with a newly developed gasification process by reducing tar and pollutant emission
Radiative Transfer in Ly{\alpha} Nebulae: I. Modeling a Continuous or Clumpy Spherical Halo with a Central Source
To understand the mechanism behind high- Ly nebulae, we simulate
the scattering of Ly in a halo about a central
Ly source. For the first time, we consider both smooth and clumpy
distributions of halo gas, as well as a range of outflow speeds, total column densities, spatial concentrations, and central source
galaxies (e.g., with Ly line widths corresponding to those typical of
AGN or star-forming galaxies). We compute the spatial-frequency diffusion and
the polarization of the Ly photons scattered by atomic hydrogen. Our
scattering-only model reproduces the typical size of Ly nebulae
(kpc) at total column densities and predicts a range of positive, flat, and negative polarization
radial gradients. We also find two general classes of Ly nebula
morphologies: with and without bright cores. Cores are seen when
is low, i.e., when the central source is directly visible, and are associated
with a polarization jump, a steep increase in the polarization radial profile
just outside the halo center. Of all the parameters tested in our smooth or
clumpy medium model, dominates the trends. The radial behaviors of
the Ly surface brightness, spectral line shape, and polarization in
the clumpy model with covering factor approach those of the
smooth model at the same . A clumpy medium with high
and low generates Ly features via scattering that
the smooth model cannot: a bright core, symmetric line profile, and
polarization jump.Comment: 42 pages, 27 figures, accepted for publication in ApJ, Comments
welcome
The Association between Apolipoprotein A-II and Metabolic Syndrome in Korean Adults: A Comparison Study of Apolipoprotein A-I and Apolipoprotein B
BackgroundApolipoprotein A-II (apoA-II) is the second-most abundant apolipoprotein in human high-density lipoprotein and its role in cardio metabolic risk is not entirely clear. It has been suggested to have poor anti-atherogenic or even pro-atherogenic properties, but there are few studies on the possible role of apoA-II in Asian populations. The aim of this study is to evaluate the role of apoA-II in metabolic syndrome (MetS) compared with apolipoprotein A-I (apoA-I) and apolipoprotein B (apoB) in Korean adults.MethodsWe analyzed data from 244 adults who visited the Center for Health Promotion in Pusan National University Yangsan Hospital for routine health examinations.ResultsThe mean apoB level was significantly higher, and the mean apoA-I level was significantly lower, in MetS; however, there was no significant difference in apoA-II levels (30.5±4.6 mg/dL vs. 31.2±4.6 mg/dL, P=0.261). ApoA-II levels were more positively correlated with apoA-I levels than apoB levels. ApoA-II levels were less negatively correlated with homocysteine and high sensitivity C-reactive protein levels than apoA-I levels. The differences in MetS prevalence from the lowest to highest quartile of apoA-II were not significant (9.0%, 5.7%, 4.9%, and 6.6%, P=0.279). The relative risk of the highest quartile of apoA-II compared with the lowest quartile also was not significantly different (odds ratio, 0.96; 95% confidence interval, 0.95 to 1.04; P=0.956).ConclusionCompared with apoA-I (negative association with MetS) and apoB (positive association with MetS) levels, apoA-II levels did not show any association with MetS in this study involving Korean adults. However, apoA-II may have both anti-atherogenic and pro-atherogenic properties
Oxygen Partial Pressure during Pulsed Laser Deposition: Deterministic Role on Thermodynamic Stability of Atomic Termination Sequence at SrRuO3/BaTiO3 Interface
With recent trends on miniaturizing oxide-based devices, the need for
atomic-scale control of surface/interface structures by pulsed laser deposition
(PLD) has increased. In particular, realizing uniform atomic termination at the
surface/interface is highly desirable. However, a lack of understanding on the
surface formation mechanism in PLD has limited a deliberate control of
surface/interface atomic stacking sequences. Here, taking the prototypical
SrRuO3/BaTiO3/SrRuO3 (SRO/BTO/SRO) heterostructure as a model system, we
investigated the formation of different interfacial termination sequences
(BaO-RuO2 or TiO2-SrO) with oxygen partial pressure (PO2) during PLD. We found
that a uniform SrO-TiO2 termination sequence at the SRO/BTO interface can be
achieved by lowering the PO2 to 5 mTorr, regardless of the total background gas
pressure (Ptotal), growth mode, or growth rate. Our results indicate that the
thermodynamic stability of the BTO surface at the low-energy kinetics stage of
PLD can play an important role in surface/interface termination formation. This
work paves the way for realizing termination engineering in functional oxide
heterostructures.Comment: 27 pages, 6 figures, Supporting Informatio
Activation of spleen tyrosine kinase is required for TNF-α-induced endothelin-1 upregulation in human aortic endothelial cells
AbstractEndothelin-1 (ET-1) promotes atherosclerosis. We tested whether spleen tyrosine kinase (Syk) mediates tumor necrosis factor-α (TNF-α)-induced ET-1 upregulation in human aortic endothelial cells (HAECs) and sought to identify the signal pathways involved. TNF-α-induced reactive oxygen species (ROS) activated Syk and phosphatidylinositol 3-kinase (PI3K), which was required for the activation of AP-1 and subsequent ET-1 gene transcription. ROS mediated c-Jun NH2-terminal kinase (JNK) is also required for AP-1 activation, but Syk and PI3K regulated AP-1 activation independently of JNK. Through regulation of ET-1 production, Syk could be implicated in atherosclerosis
Prognostic Factors and Clinical Outcomes of High-Dose Chemotherapy followed by Autologous Stem Cell Transplantation in Patients with Peripheral T Cell Lymphoma, Unspecified: Complete Remission at Transplantation and the Prognostic Index of Peripheral T Cell Lymphoma Are the Major Factors Predictive of Outcome
AbstractHigh-dose chemotherapy followed by autologous stem cell transplantation (HDT/ASCT) offers a rescue option for T cell lymphoma patients with poor prognosis. However, the effectiveness of HDT/ASCT in patients with various peripheral T cell subtypes, optimal transplant timing, and the prognostic factors that predict better outcomes, have not been identified. We retrospectively investigated the clinical outcomes and prognostic factors for HDT/ASCT in 64 Korean patients with peripheral T cell lymphoma, unspecified (PTCL-U) between March 1995 and February 2007. The median age at transplantation was 44 years (range: 15-63 years). According to the age-adjusted International Prognostic Index (a-IPI) and the prognostic index of PTCL (PIT), 8 patients (12.5%) were in the high-risk group and 16 (26.6%) had the 2-3 PIT factors, respectively. After a median follow-up of 29.7 months, the 3-year overall survival (OS) and progression-free survival (PFS) rates were 53.0% ± 7.5% and 44.3% ± 7.0%, respectively. Univariate analysis showed that poor performance status, high lactate dehydrogenase (LDH) levels, high a-IPI score, high PIT classes, failure to achieve complete response (CR) at transplantation, and nonfrontline transplantation were associated with poor OS. Multivariate analysis showed that failure to achieve CR at transplantation (hazard ratio [HR] 2.23; 95% confidence interval [CI] 1.78-7.93) and 2-3 PIT factors (HR 3.76; 95% CI 1.02-5.42) were independent prognostic factors for OS. Failure to achieve CR at transplantation and high PIT are negative predictable factors for survival following HDT/ASCT in patients with PTCL-U
Impact of Left Atrial Appendage Morphology on Recurrence in Embolic Stroke of Undetermined Source and Atrial Cardiopathy
Background: The left atrial appendage (LAA) is a major source of thrombus and non-chicken wing (CW). LAA morphology is a risk factor for embolic events in atrial fibrillation. However, the association of non-CW morphology with embolic stroke recurrence is unknown in patients with embolic stroke of undetermined source (ESUS) and atrial cardiopathy.Methods: We conducted retrospective analyses using a prospective institutional stroke registry (2013–2017). Patients with ESUS and atrial cardiopathy were enrolled. Atrial cardiopathy was diagnosed if an increased left atrial diameter (>40 mm, men; >38 mm, women), supraventricular tachycardia, or LAA filling defect on computed tomography (CT) were present. Patients admitted >24 h after onset were excluded. LAA morphology was evaluated using CT and categorized into CW vs. non-CW types. The primary outcome was embolic stroke recurrence. Multivariable Cox proportional hazards models were used to examine the independent association between LAA morphology and outcome.Results: Of 157 patients, 81 (51.6%) had CW LAA morphology. The median follow-up was 41.5 (interquartile range 12.3–58.5) months corresponding to 509.8 patient years. In total, 18 participants experienced embolic stroke recurrences (3.80 per 100 patient-years). Non-CW morphology was more associated with embolic stroke recurrence than CW morphology (hazard ratio (HR), 3.17; 95% confidence interval (CI), 1.13–8.91; p = 0.029). After adjusting for CHA2DS2-VASc score and number of potential embolic sources, non-CW morphology showed an independent association with outcome (adjusted HR, 2.90; 95% CI, 1.02–8.23; p = 0.045).Conclusions: The LAA morphology types may help identify high risk of embolic stroke recurrence in ESUS with atrial cardiopathy. LAA morphology in atrial cardiopathy may provide clues for developing therapies tailored to specific mechanisms
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