2,621 research outputs found
Decomposed Temporal Dynamic CNN: Efficient Time-Adaptive Network for Text-Independent Speaker Verification Explained with Speaker Activation Map
Temporal dynamic models for text-independent speaker verification extract
consistent speaker information regardless of phonemes by using temporal dynamic
CNN (TDY-CNN) in which kernels adapt to each time bin. However, TDY-CNN shows
limitations that the model is too large and does not guarantee the diversity of
adaptive kernels. To address these limitations, we propose decomposed temporal
dynamic CNN (DTDY-CNN) that makes adaptive kernel by combining static kernel
and dynamic residual based on matrix decomposition. The baseline model using
DTDY-CNN maintained speaker verification performance while reducing the number
of model parameters by 35% compared to the model using TDY-CNN. In addition,
detailed behaviors of temporal dynamic models on extraction of speaker
information was explained using speaker activation maps (SAM) modified from
gradient-weighted class activation mapping (Grad-CAM). In DTDY-CNN, the static
kernel activates voiced features of utterances, and the dynamic residual
activates unvoiced high-frequency features of phonemes. DTDY-CNN effectively
extracts speaker information from not only formant frequencies and harmonics
but also detailed unvoiced phonemes' information, thus explaining its
outstanding performance on text-independent speaker verification.Comment: Submitted to InterSpeech 202
Frequency Dynamic Convolution: Frequency-Adaptive Pattern Recognition for Sound Event Detection
2D convolution is widely used in sound event detection (SED) to recognize 2D
patterns of sound events in time-frequency domain. However, 2D convolution
enforces translation-invariance on sound events along both time and frequency
axis while sound events exhibit frequency-dependent patterns. In order to
improve physical inconsistency in 2D convolution on SED, we propose frequency
dynamic convolution which applies kernel that adapts to frequency components of
input. Frequency dynamic convolution outperforms the baseline model by 6.3% in
DESED dataset in terms of polyphonic sound detection score (PSDS). It also
significantly outperforms dynamic convolution and temporal dynamic convolution
on SED. In addition, by comparing class-wise F1 scores of baseline model and
frequency dynamic convolution, we showed that frequency dynamic convolution is
especially more effective for detection of non-stationary sound events. From
this result, we verified that frequency dynamic convolution is superior in
recognizing frequency-dependent patterns as non-stationary sound events show
more intricate time-frequency patterns.Comment: Submitted to INTERSPEECH 202
Toxic effects of ammonia exposure on growth performance, hematological parameters, and plasma components in rockfish, Sebastes schlegelii, during thermal stress
Abstract Rockfish, Sebastes schlegelii (mean length 14.53 ± 1.14 cm and mean weight 38.36 ± 3.45 g), were exposed for 4 weeks with the different levels of ammonia in the concentrations of 0, 0.1, 0.5, and 1.0 mg/L at 19 and 24 °C. The indicators of growth performance such as daily length gain, daily weight gain, condition factor, and hematosomatic index were significantly reduced by the ammonia exposure and high temperature. The ammonia exposure induced a significant decrease in hematological parameters, such as red blood cell (RBC) count, white blood cell (WBC) count, hemoglobin (Hb), and hematocrit (Ht), whose trend was more remarkable at 24 °C. Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were also notably decreased by the ammonia exposure. Blood ammonia concentration was considerably increased by the ammonia concentration exposure. In the serum components, the glucose, glutamic oxalate transaminase (GOT), and glutamic pyruvate transaminase (GPT) were substantially increased by the ammonia exposure, whereas total protein was significantly decreased. But, the calcium and magnesium were not considerably changed
Metastatic Gastric Adenocarcinoma Presenting as a Solitary Plaque on the Palm
Cutaneous metastases from gastric adenocarcinoma are extremely rare. When present, metastasis typically signifies disseminated disease with a poor prognosis. We report a case of an 80-year-old male with gastric cancer who presented with a single, erythematous plaque on the left palm, a very rare site for skin metastasis. Results of a skin biopsy demonstrated that the cutaneous metastasis originated from the stomach. This report emphasized the need for appropriate investigation into newly appearing, unusual, or persistent skin lesions
Solitary Extrahepatic Intraabdominal Metastasis from Hepatocellular Carcinoma after Liver Transplantation
A liver transplantation is a treatment option in selected patients with hepatocellular carcinoma (HCC). Despite the adequate selection of candidates, recurrences of HCC may still develop. Solitary extrahepatic metastasis from HCC after a liver transplantation is rare. Here we report two cases of HCC demonstrated extrahepatic recurrence to the adrenal gland and spleen, respectively, within one year after a liver transplantation. Since the treatment of solitary extrahepatic metastasis from HCC after a liver transplantation is not standardized, surgical resection was performed. In the case of HCC adrenal metastasis, innumerable intrahepatic metastases were found two months after the adrenalectomy. And 16 months after adrenalectomy, the patient expired due to tumor progression and hepatic failure. In the case of HCC splenic metastasis, postoperative radiation therapy was performed. However, two recurrent HCC nodules were found 15 months after the splenectomy and received transarterial chemoembolization (TACE). And 29 month after the splenectomy, the patient also expired as same causes of former patient
Acute Appendicitis in Henoch-Schönlein Purpura : A Case Report
Common complications of Henoch-Schönlein purpura (HSP) that lead to surgical intervention include intussusception, perforation, necrosis, and massive gastrointestinal bleeding. Acute appendicitis is rarely seen as a complication of HSP. A seven-year-old boy was admitted for arthralgia, abdominal pain, hematochezia, melena, and purpuric rash on the lower extremities. On admission day abdominal ultrasonography was normal, but on day 5, he became pyrexial and developed right iliac fossa pain and tenderness with guarding. Ultrasonography showed distended appendix surrounded by hyperechoic inflamed fat. On exploration an acutely inflamed, necrotic appendix was removed and grossly there was an appendiceal perforation in the appendiceal tip. Microscopically some of the small blood vessels in the submucosa showed fibrinoid necrosis with neutrophilic infiltrations. The authors report the case of a child who developed acute perforative appendicitis requiring appendectomy while on treatment for HSP
Suppression of lung cancer progression by biocompatible glycerol triacrylate–spermine-mediated delivery of shAkt1
Background: Polyethylenimine (PEI)-based nonviral gene-delivery systems are commonly employed because of their high transfection efficiency. However, the toxic nature of PEI is a significant obstacle in clinical gene therapy. In this study, we developed biocompatible glycerol triacrylate-spermine (GT-SPE) polyspermine as a nanosized gene carrier for potential lung cancer gene therapy. Methods: The GT-SPE was synthesized using the Michael addition reaction between GT and SPE. The molecular weight was characterized using gel permeability chromatography multiangle laser light scattering and the composition of the polymer was analyzed using proton nuclear magnetic resonance. Results: The GT-SPE successfully protected the DNA from nucleases. The average particle size of the GT-SPE was 121 nm with a zeta potential of +23.45 mV. The GT-SPE was found to be less toxic than PEI for various cell lines, as well as for a murine model. Finally, our results showed that the GT-SPE/small hairpin Akt1 (shAkt1) complex suppressed lung tumorigenesis in a K-ras(LA1) lung cancer mice model by inducing apoptosis through the Akt signaling pathway and cell cycle arrest. Aerosol delivered GT-SPE/shAkt1, which reduced matrix metalloproteinase-9 activity and suppressed the expression levels of proliferating cell nuclear antigen, as well as vascular endothelial growth factors and CD31, which are known proliferation and angiogenesis markers, respectively. Conclusion: Our data suggest that GT-SPE may be a candidate for short hairpin-shaped RNA-based aerosol lung cancer gene therapy
An Arrhythmia Classification-Guided Segmentation Model for Electrocardiogram Delineation
Accurate delineation of key waveforms in an ECG is a critical initial step in
extracting relevant features to support the diagnosis and treatment of heart
conditions. Although deep learning based methods using a segmentation model to
locate P, QRS and T waves have shown promising results, their ability to handle
signals exhibiting arrhythmia remains unclear. In this study, we propose a
novel approach that leverages a deep learning model to accurately delineate
signals with a wide range of arrhythmia. Our approach involves training a
segmentation model using a hybrid loss function that combines segmentation with
the task of arrhythmia classification. In addition, we use a diverse training
set containing various arrhythmia types, enabling our model to handle a wide
range of challenging cases. Experimental results show that our model accurately
delineates signals with a broad range of abnormal rhythm types, and the
combined training with classification guidance can effectively reduce false
positive P wave predictions, particularly during atrial fibrillation and atrial
flutter. Furthermore, our proposed method shows competitive performance with
previous delineation algorithms on the Lobachevsky University Database (LUDB)
Assessment of the viability of integrating virtual reality programs in practical tests for the Korean Radiological Technologists Licensing Examination: a survey study
Purpose The objective of this study was to assess the feasibility of incorporating virtual reality/augmented reality (VR/AR) programs into practical tests administered as part of the Korean Radiological Technologists Licensing Examination (KRTLE). This evaluation is grounded in a comprehensive survey that targeted enrolled students in departments of radiology across the nation. Methods In total, 682 students from radiology departments across the nation were participants in the survey. An online survey platform was used, and the questionnaire was structured into 5 distinct sections and 27 questions. A frequency analysis for each section of the survey was conducted using IBM SPSS ver. 27.0. Results Direct or indirect exposure to VR/AR content was reported by 67.7% of all respondents. Furthermore, 55.4% of the respondents expressed that VR/AR could be integrated into their classes, which signified a widespread acknowledgment of VR among the students. With regards to the integration of a VR/AR or mixed reality program into the practical tests for purposes of the KRTLE, a substantial amount of the respondents (57.3%) exhibited a positive inclination and recommended its introduction. Conclusion The application of VR/AR programs within practical tests of the KRTLE will be used as an alternative for evaluating clinical examination procedures and validating job skills
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