103 research outputs found
Association Between Sars-Cov-2 Reinfections And Anti-S Antibody Levels At The First Omicron Wave In Salvador, Brazil
Background: SARS-CoV-2, with its high transmissibility and rapid dissemination, has caused a global public health emergency. The emergence of new variants and mutations of SARSCoV-2 spike protein antigens has led to concerns about immune escape and the potential for reinfection, even in individuals who have been previously infected or vaccinated. Brazil has been severely affected by the pandemic, especially in its densely populated slum areas. Our study aimed to evaluate the association between anti-S IgG antibody levels and subsequent SARS-CoV-2 infection during the Omicron wave in a susceptible community in Salvador, Brazil, to provide insight into the antibody level necessary for effective protection against infection with heterologous variants in similar settings. Methods and findings: We conducted this study in a cohort of 1827 residents of Pau da Lima, Salvador, Brazil. We measured serum levels of IgG against the SARS-CoV-2 Spike protein between July and November 2021. From November 2021 to February 2022, during the first Omicron wave, we performed symptom-based screening and PCR testing to identify new infections. We used logistic regression to estimate the association between antibody levels and subsequent PCR-confirmed infection. Among 210 individuals in the cohort who underwent PCR testing, we did not identify any association between antibody levels and PCR-confirmed infection. Among a subset of 84 individuals who did not receive vaccination between the time of antibody measurement and the time of PCR testing, higher antibody levels were associated with increased odds of PCR-confirmed infection. Conclusion: We did not identify a protective effect of serum anti-S IgG levels on subsequent risk of infection during the Omicron wave. Further studies could address limitations of our study (sample size, confounding) and evaluate the effect of variant-specific antibodie
Accelerating Toeplitz Neural Network with Constant-time Inference Complexity
Toeplitz Neural Networks (TNNs) have exhibited outstanding performance in
various sequence modeling tasks. They outperform commonly used
Transformer-based models while benefiting from log-linear space-time
complexities. On the other hand, State Space Models (SSMs) achieve lower
performance than TNNs in language modeling but offer the advantage of constant
inference complexity. In this paper, we aim to combine the strengths of TNNs
and SSMs by converting TNNs to SSMs during inference, thereby enabling TNNs to
achieve the same constant inference complexities as SSMs. To accomplish this,
we formulate the conversion process as an optimization problem and provide a
closed-form solution. We demonstrate how to transform the target equation into
a Vandermonde linear system problem, which can be efficiently solved using the
Discrete Fourier Transform (DFT). Notably, our method requires no training and
maintains numerical stability. It can be also applied to any LongConv-based
model. To assess its effectiveness, we conduct extensive experiments on
language modeling tasks across various settings. Additionally, we compare our
method to other gradient-descent solutions, highlighting the superior numerical
stability of our approach. The source code is available at
https://github.com/OpenNLPLab/ETSC-Exact-Toeplitz-to-SSM-Conversion.Comment: Accepted to EMNLP 2023. Yiran Zhong is the corresponding author. The
source code is available at
https://github.com/OpenNLPLab/ETSC-Exact-Toeplitz-to-SSM-Conversio
Bibliometric and visualization analysis of research trend in mental health problems of children and adolescents during the COVID-19 pandemic
ObjectivesTo analyze the evolution of research on children and adolescents mental health issues during COVID-19 pandemic and discuss research hotspots and cutting-edge developments.MethodsThe literature obtained from the web of science core collection as of June 28, 2022, was analyzed using Citespace, VOSviewer bibliometric visualization mapping software.ResultsA total of 6,039 relevant papers were found, of which 5,594 were included in the study. The number of literatures is growing since 2020; and the country, institution, and journal publications were analyzed. The co-citation analysis shows that there are more research articles among the highly cited articles and a lack of systematic reviews that use critical thinking for review. In the cluster analysis, mental health and life change were the most representative. The timeline view of the keywords shows that Online learning (#0), Public health (#1), and Mental health (#2) are the three largest clusters and shows the change over time.ConclusionThis study helped analyze the mental health of children and adolescents during the COVID-19 pandemic and identified hot trends and shortcomings, which are important references for the theoretical basis of future research and decision making and technical guidance for systematic reviews
SupFusion: Supervised LiDAR-Camera Fusion for 3D Object Detection
In this paper, we propose a novel training strategy called SupFusion, which
provides an auxiliary feature level supervision for effective LiDAR-Camera
fusion and significantly boosts detection performance. Our strategy involves a
data enhancement method named Polar Sampling, which densifies sparse objects
and trains an assistant model to generate high-quality features as the
supervision. These features are then used to train the LiDAR-Camera fusion
model, where the fusion feature is optimized to simulate the generated
high-quality features. Furthermore, we propose a simple yet effective deep
fusion module, which contiguously gains superior performance compared with
previous fusion methods with SupFusion strategy. In such a manner, our proposal
shares the following advantages. Firstly, SupFusion introduces auxiliary
feature-level supervision which could boost LiDAR-Camera detection performance
without introducing extra inference costs. Secondly, the proposed deep fusion
could continuously improve the detector's abilities. Our proposed SupFusion and
deep fusion module is plug-and-play, we make extensive experiments to
demonstrate its effectiveness. Specifically, we gain around 2% 3D mAP
improvements on KITTI benchmark based on multiple LiDAR-Camera 3D detectors.Comment: Accepted to ICCV202
All-pairs Consistency Learning for Weakly Supervised Semantic Segmentation
In this work, we propose a new transformer-based regularization to better
localize objects for Weakly supervised semantic segmentation (WSSS). In
image-level WSSS, Class Activation Map (CAM) is adopted to generate object
localization as pseudo segmentation labels. To address the partial activation
issue of the CAMs, consistency regularization is employed to maintain
activation intensity invariance across various image augmentations. However,
such methods ignore pair-wise relations among regions within each CAM, which
capture context and should also be invariant across image views. To this end,
we propose a new all-pairs consistency regularization (ACR). Given a pair of
augmented views, our approach regularizes the activation intensities between a
pair of augmented views, while also ensuring that the affinity across regions
within each view remains consistent. We adopt vision transformers as the
self-attention mechanism naturally embeds pair-wise affinity. This enables us
to simply regularize the distance between the attention matrices of augmented
image pairs. Additionally, we introduce a novel class-wise localization method
that leverages the gradients of the class token. Our method can be seamlessly
integrated into existing WSSS methods using transformers without modifying the
architectures. We evaluate our method on PASCAL VOC and MS COCO datasets. Our
method produces noticeably better class localization maps (67.3% mIoU on PASCAL
VOC train), resulting in superior WSSS performances.Comment: ICCV 2023 worksho
Linearized Relative Positional Encoding
Relative positional encoding is widely used in vanilla and linear
transformers to represent positional information. However, existing encoding
methods of a vanilla transformer are not always directly applicable to a linear
transformer, because the latter requires a decomposition of the query and key
representations into separate kernel functions. Nevertheless, principles for
designing encoding methods suitable for linear transformers remain
understudied. In this work, we put together a variety of existing linear
relative positional encoding approaches under a canonical form and further
propose a family of linear relative positional encoding algorithms via unitary
transformation. Our formulation leads to a principled framework that can be
used to develop new relative positional encoding methods that preserve linear
space-time complexity. Equipped with different models, the proposed linearized
relative positional encoding (LRPE) family derives effective encoding for
various applications. Experiments show that compared with existing methods,
LRPE achieves state-of-the-art performance in language modeling, text
classification, and image classification. Meanwhile, it emphasizes a general
paradigm for designing broadly more relative positional encoding methods that
are applicable to linear transformers. The code is available at
https://github.com/OpenNLPLab/Lrpe.Comment: Reviewed by TMLR, decision pending. Yiran Zhong is the corresponding
author. Code is available at https://github.com/OpenNLPLab/Lrp
Fine-grained Audible Video Description
We explore a new task for audio-visual-language modeling called fine-grained
audible video description (FAVD). It aims to provide detailed textual
descriptions for the given audible videos, including the appearance and spatial
locations of each object, the actions of moving objects, and the sounds in
videos. Existing visual-language modeling tasks often concentrate on visual
cues in videos while undervaluing the language and audio modalities. On the
other hand, FAVD requires not only audio-visual-language modeling skills but
also paragraph-level language generation abilities. We construct the first
fine-grained audible video description benchmark (FAVDBench) to facilitate this
research. For each video clip, we first provide a one-sentence summary of the
video, ie, the caption, followed by 4-6 sentences describing the visual details
and 1-2 audio-related descriptions at the end. The descriptions are provided in
both English and Chinese. We create two new metrics for this task: an
EntityScore to gauge the completeness of entities in the visual descriptions,
and an AudioScore to assess the audio descriptions. As a preliminary approach
to this task, we propose an audio-visual-language transformer that extends
existing video captioning model with an additional audio branch. We combine the
masked language modeling and auto-regressive language modeling losses to
optimize our model so that it can produce paragraph-level descriptions. We
illustrate the efficiency of our model in audio-visual-language modeling by
evaluating it against the proposed benchmark using both conventional captioning
metrics and our proposed metrics. We further put our benchmark to the test in
video generation models, demonstrating that employing fine-grained video
descriptions can create more intricate videos than using captions.Comment: accpeted to CVPR 2023, Xuyang Shen, Dong Li and Jinxing Zhou
contribute equally, code link: github.com/OpenNLPLab/FAVDBench, dataset link:
www.avlbench.opennlplab.c
The PIAS-like Coactivator Zmiz1 Is a Direct and Selective Cofactor of Notch1 in T Cell Development and Leukemia
SummaryPan-NOTCH inhibitors are poorly tolerated in clinical trials because NOTCH signals are crucial for intestinal homeostasis. These inhibitors might also promote cancer because NOTCH can act as a tumor suppressor. We previously reported that the PIAS-like coactivator ZMIZ1 is frequently co-expressed with activated NOTCH1 in T cell acute lymphoblastic leukemia (T-ALL). Here, we show that similar to Notch1, Zmiz1 was important for T cell development and controlled the expression of certain Notch target genes, such as Myc. However, unlike Notch, Zmiz1 had no major role in intestinal homeostasis or myeloid suppression. Deletion of Zmiz1 impaired the initiation and maintenance of Notch-induced T-ALL. Zmiz1 directly interacted with Notch1 via a tetratricopeptide repeat domain at a special class of Notch-regulatory sites. In contrast to the Notch cofactor Maml, which is nonselective, Zmiz1 was selective. Thus, targeting the NOTCH1-ZMIZ1 interaction might combat leukemic growth while avoiding the intolerable toxicities of NOTCH inhibitors
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