1,822 research outputs found
Relation Modeling with Graph Convolutional Networks for Facial Action Unit Detection
Most existing AU detection works considering AU relationships are relying on
probabilistic graphical models with manually extracted features. This paper
proposes an end-to-end deep learning framework for facial AU detection with
graph convolutional network (GCN) for AU relation modeling, which has not been
explored before. In particular, AU related regions are extracted firstly,
latent representations full of AU information are learned through an
auto-encoder. Moreover, each latent representation vector is feed into GCN as a
node, the connection mode of GCN is determined based on the relationships of
AUs. Finally, the assembled features updated through GCN are concatenated for
AU detection. Extensive experiments on BP4D and DISFA benchmarks demonstrate
that our framework significantly outperforms the state-of-the-art methods for
facial AU detection. The proposed framework is also validated through a series
of ablation studies.Comment: Accepted by MMM202
Recommended from our members
Associations between vaccination and quality of life among Taiwan general population: a comparison between COVID-19 vaccines and flu vaccines
The COVID-19 pandemic has profoundly impacted lives worldwide and has led to global vaccination against COVID-19. However, there are concerns about the adverse effects of such vaccines on individuals’ health. Therefore, it is important to investigate the association between vaccination and holistic health outcome (i.e., quality of life [QoL]). The present study analyzed data from the Taiwan Social Change Survey (TSCS), a survey conducted utilizing stratified random sampling. More specifically, data (N = 1425; 47.44% males; mean age = 50.58 y) on their vaccinations (including COVID-19 and flu vaccines) and QoL (using the Short-Form 12) were used. Participants were separated into two age subgroups for analyses (those aged below 50 y, and those 50 y or above). For participants aged below 50 y, those who received COVID-19 vaccine and those who received both COVID-19 and flu vaccines had significantly better physical QoL than those who did not receive any vaccination. Mental QoL was not significantly associated with vaccinations for participants aged below 50 y. Moreover, neither mental nor physical QoL was significantly associated with vaccinations for those aged 50 y or above. The present study showed that not having COVID-19 and flu vaccinations is associated with poor QoL. This finding should be disseminated to the public to help aid vaccination promotion
Cooperative coupling of ultracold atoms and surface plasmons
Cooperative coupling between optical emitters and light fields is one of the
outstanding goals in quantum technology. It is both fundamentally interesting
for the extraordinary radiation properties of the participating emitters and
has many potential applications in photonics. While this goal has been achieved
using high-finesse optical cavities, cavity-free approaches that are broadband
and easy to build have attracted much attention recently. Here we demonstrate
cooperative coupling of ultracold atoms with surface plasmons propagating on a
plane gold surface. While the atoms are moving towards the surface they are
excited by an external laser pulse. Excited surface plasmons are detected via
leakage radiation into the substrate of the gold layer. A maximum Purcell
factor of is reached at an optimum distance of
from the surface. The coupling leads to the observation of
a Fano-like resonance in the spectrum.Comment: 9 pages, 4 figure
Where Does Mediator Bind In Vivo?
Background: The Mediator complex associates with RNA polymerase (Pol) II, and it is recruited to enhancer regions by activator proteins under appropriate environmental conditions. However, the issue of Mediator association in yeast cells is controversial. Under optimal growth conditions (YPD medium), we were unable to detect Mediator at essentially any S. cerevisiae promoter region, including those supporting very high levels of transcription. In contrast, whole genome microarray experiments in synthetic complete (SC) medium reported that Mediator associates with many genes at both promoter and coding regions. Principal Findings: As assayed by chromatin immunoprecipitation, we show that there are a small number of Mediator targets in SC medium that are not observed in YPD medium. However, most Mediator targets identified in the genome-wide analysis are false positives that arose for several interrelated reasons: the use of overly lenient cut-offs; artifactual differences in apparent IP efficiencies among different genomic regions in the untagged strain; low fold-enrichments making it difficult to distinguish true Mediator targets from false positives that occur in the absence of the tagged Mediator protein. Lastly, apparent Mediator association in highly active coding regions is due to a non-specific effect on accessibility due to the lack of nucleosomes, not to a specific association of Mediator. Conclusions: These results indicate that Mediator does not bind to numerous sites in the yeast genome, but rathe
Control of intestinal stem cell function and proliferation by mitochondrial pyruvate metabolism.
Most differentiated cells convert glucose to pyruvate in the cytosol through glycolysis, followed by pyruvate oxidation in the mitochondria. These processes are linked by the mitochondrial pyruvate carrier (MPC), which is required for efficient mitochondrial pyruvate uptake. In contrast, proliferative cells, including many cancer and stem cells, perform glycolysis robustly but limit fractional mitochondrial pyruvate oxidation. We sought to understand the role this transition from glycolysis to pyruvate oxidation plays in stem cell maintenance and differentiation. Loss of the MPC in Lgr5-EGFP-positive stem cells, or treatment of intestinal organoids with an MPC inhibitor, increases proliferation and expands the stem cell compartment. Similarly, genetic deletion of the MPC in Drosophila intestinal stem cells also increases proliferation, whereas MPC overexpression suppresses stem cell proliferation. These data demonstrate that limiting mitochondrial pyruvate metabolism is necessary and sufficient to maintain the proliferation of intestinal stem cells
Recommended from our members
Fast and slow responses of Southern Ocean sea surface temperature to SAM in coupled climate models
We investigate how sea surface temperatures (SSTs) around Antarctica respond to the Southern An- nular Mode (SAM) on multiple timescales. To that end we examine the relationship between SAM and SST within unperturbed preindustrial control simulations of coupled general circulation models (GCMs) included in the Climate Modeling Intercomparison Project phase 5 (CMIP5). We develop a technique to extract the re- sponse of the Southern Ocean SST (55◦S−70◦S) to a hypothetical step increase in the SAM index. We demonstrate that in many GCMs, the expected SST step re- sponse function is nonmonotonic in time. Following a shift to a positive SAM anomaly, an initial cooling regime can transition into surface warming around Antarctica. However, there are large differences across the CMIP5 ensemble. In some models the step response function never changes sign and cooling persists, while in other GCMs the SST anomaly crosses over from negative to positive values only three years after a step increase in the SAM. This intermodel diversity can be related to differences in the models’ climatological thermal ocean stratification in the region of seasonal sea ice around Antarctica. Exploiting this relationship, we use obser- vational data for the time-mean meridional and vertical temperature gradients to constrain the real Southern Ocean response to SAM on fast and slow timescales
Method for Flow Measurement in Microfluidic Channels Based on Electrical Impedance Spectroscopy
We have developed and characterized two novel micro flow sensors based on
measuring the electrical impedance of the interface between the flowing liquid
and metallic electrodes embedded on the channel walls. These flow sensors are
very simple to fabricate and use, are extremely compact and can easily be
integrated into most microfluidic systems. One of these devices is a micropore
with two tantalum/platinum electrodes on its edges; the other is a micro
channel with two tantalum /platinum electrodes placed perpendicular to the
channel on its walls. In both sensors the flow rate is measured via the
electrical impedance between the two metallic electrodes, which is the
impedance of two metal-liquid junctions in series. The dependency of the
metal-liquid junction impedance on the flow rate of the liquid has been
studied. The effects of different parameters on the sensor's outputs and its
noise behavior are investigated. Design guidelines are extracted and applied to
achieve highly sensitive micro flow sensors with low noise.Comment: 11 pages, 7 figure
Induction of Stable Drug Resistance in Human Breast Cancer Cells Using a Combinatorial Zinc Finger Transcription Factor Library
Combinatorial libraries of artificial zinc-finger transcription factors (ZF-TFs) provide a robust tool for inducing and understanding various functional components of the cancer phenotype. Herein, we utilized combinatorial ZF-TF library technology to better understand how breast cancer cells acquire resistance to fulvestrant, a clinically important anti-endocrine therapeutic agent. From a diverse collection of nearly 400,000 different ZF-TFs, we isolated six ZF-TF library members capable of inducing stable, long-term anti-endocrine drug-resistance in two independent estrogen receptor-positive breast cancer cell lines. Comparative gene expression profile analysis of the six different ZF-TF-transduced breast cancer cell lines revealed five distinct clusters of differentially expressed genes. One cluster was shared among all 6 ZF-TF-transduced cell lines and therefore constituted a common fulvestrant-resistant gene expression signature. Pathway enrichment-analysis of this common fulvestrant resistant signature also revealed significant overlap with gene sets associated with an estrogen receptor-negative-like state and with gene sets associated with drug resistance to different classes of breast cancer anti-endocrine therapeutic agents. Enrichment-analysis of the four remaining unique gene clusters revealed overlap with myb-regulated genes. Finally, we also demonstrated that the common fulvestrant-resistant signature is associated with poor prognosis by interrogating five independent, publicly available human breast cancer gene expression datasets. Our results demonstrate that artificial ZF-TF libraries can be used successfully to induce stable drug-resistance in human cancer cell lines and to identify a gene expression signature that is associated with a clinically relevant drug-resistance phenotype
Constitutive Notch2 signaling in neural stem cells promotes tumorigenic features and astroglial lineage entry
Recent studies identified a highly tumorigenic subpopulation of glioma stem cells (GSCs) within malignant gliomas. GSCs are proposed to originate from transformed neural stem cells (NSCs). Several pathways active in NSCs, including the Notch pathway, were shown to promote proliferation and tumorigenesis in GSCs. Notch2 is highly expressed in glioblastoma multiforme (GBM), a highly malignant astrocytoma. It is therefore conceivable that increased Notch2 signaling in NSCs contributes to the formation of GBM. Here, we demonstrate that mice constitutively expressing the activated intracellular domain of Notch2 in NSCs display a hyperplasia of the neurogenic niche and reduced neuronal lineage entry. Neurospheres derived from these mice show increased proliferation, survival and resistance to apoptosis. Moreover, they preferentially differentiate into astrocytes, which are the characteristic cellular population of astrocytoma. Likewise, we show that Notch2 signaling increases proliferation and resistance to apoptosis in human GBM cell lines. Gene expression profiling of GBM patient tumor samples reveals a positive correlation of Notch2 transcripts with gene transcripts controlling anti-apoptotic processes, stemness and astrocyte fate, and a negative correlation with gene transcripts controlling proapoptotic processes and oligodendrocyte fate. Our data show that Notch2 signaling in NSCs produces features of GSCs and induces astrocytic lineage entry, consistent with a possible role in astrocytoma formation
Type IV Pili of Acidithiobacillus ferrooxidans Are Necessary for Sliding, Twitching Motility, and Adherence
We used conventional methods to investigate the mechanism by which Acidithiobacillus ferrooxidans colonizes a solid surface by assessing pili-mediated sliding, twitching motility, and adherence. A. ferrooxidans slided to form circular oxidized zones around each colony. This suggested that slide motility occurs through pili or flagella, though A. ferrooxidans strains ATCC 19859 and ATCC 23270 lack flagella. The results of reverse transcription-PCR demonstrated that the putative major pili gene of A. ferrooxidans strains ATCC 19859, ATCC 23270, and BY3 genes were transcribed. Culture of A. ferrooxidans between silicone gel and glass led to the production of type IV pili and the formation of rough twitching motility zones. When the bacteria were grown on lean ore cubes, pyrite was colonized readily by A. ferrooxidans and there is a correlation between pilus expression and strong attachment. However, non-pili bacteria attached minimally to the mineral surface. The results show a correlation between these functions and pilus expression
- …