23 research outputs found
Degree of Change in Bystander Cardiopulmonary Resuscitation Rate During the Onset of the Global COVID-19 Pandemic in the State of Michigan
The purpose of this study is to understand how COVID-19 has affected bystander performance of cardiopulmonary resuscitation (CPR) for out-of-hospital cardiac arrest (OHCA) patients. Studies have shown that bystander CPR can double or triple a person's chance of survival. However, during the onset and aftermath of the global COVID-19 pandemic, the risk for COVID-19 exposure during CPR for OHCA is a significant concern for bystanders. I hypothesize that, as a result of COVID-19 pandemic, the rates of bystander CPR have decreased significantly. To test this hypothesis, I conducted a quantitative research study by using data from the Cardiac Arrest Registry to Enhance Survival (CARES) registry - a nationwide central registry of OHCA data collected from emergency medical services (EMS) agencies. For this study, Michigan CARES data from January 1 to June 30, 2019 and from January 1 to June 30, 2020 were compared. In a comparison of 844 OHCA in 2019 and 8591 in 2020, the proportion of cases receiving bystander CPR was lower in 2020 (25% vs 28%, p = 0.78); An increased proportion of OHCA occurred in the home (86% vs. 82%, p = 0.44), and decreased proportion in public spaces (14% vs 18%, p = 0.16). There were more monthly OHCA cases overall on average (143 vs 141, p = 0.79) and the survival to hospital admission rate was lower during pandemic period (25% vs 28%, p = 0.24). Per my analysis, the decrease in the rate of bystander CPR in 2020 during the pandemic is not statistically significant. However, it is reassuring that the COVID-19 pandemic did not seem to significant impact the rate of bystander CPR as we know that early CPR is critical to optimal outcomes for people experiencing OHCA and for the professionals who work to maximize the rate of bystander CPR during OHCA.Master of Health InformaticsSchool of Informationhttp://deepblue.lib.umich.edu/bitstream/2027.42/168559/1/20210427_Pan,Helen[Yunzhu]_Final_MTOP_Thesis.pd
An Image Dataset for Benchmarking Recommender Systems with Raw Pixels
Recommender systems (RS) have achieved significant success by leveraging
explicit identification (ID) features. However, the full potential of content
features, especially the pure image pixel features, remains relatively
unexplored. The limited availability of large, diverse, and content-driven
image recommendation datasets has hindered the use of raw images as item
representations. In this regard, we present PixelRec, a massive image-centric
recommendation dataset that includes approximately 200 million user-image
interactions, 30 million users, and 400,000 high-quality cover images. By
providing direct access to raw image pixels, PixelRec enables recommendation
models to learn item representation directly from them. To demonstrate its
utility, we begin by presenting the results of several classical pure ID-based
baseline models, termed IDNet, trained on PixelRec. Then, to show the
effectiveness of the dataset's image features, we substitute the itemID
embeddings (from IDNet) with a powerful vision encoder that represents items
using their raw image pixels. This new model is dubbed PixelNet.Our findings
indicate that even in standard, non-cold start recommendation settings where
IDNet is recognized as highly effective, PixelNet can already perform equally
well or even better than IDNet. Moreover, PixelNet has several other notable
advantages over IDNet, such as being more effective in cold-start and
cross-domain recommendation scenarios. These results underscore the importance
of visual features in PixelRec. We believe that PixelRec can serve as a
critical resource and testing ground for research on recommendation models that
emphasize image pixel content. The dataset, code, and leaderboard will be
available at https://github.com/westlake-repl/PixelRec
Understanding and Modeling Passive-Negative Feedback for Short-video Sequential Recommendation
Sequential recommendation is one of the most important tasks in recommender
systems, which aims to recommend the next interacted item with historical
behaviors as input. Traditional sequential recommendation always mainly
considers the collected positive feedback such as click, purchase, etc.
However, in short-video platforms such as TikTok, video viewing behavior may
not always represent positive feedback. Specifically, the videos are played
automatically, and users passively receive the recommended videos. In this new
scenario, users passively express negative feedback by skipping over videos
they do not like, which provides valuable information about their preferences.
Different from the negative feedback studied in traditional recommender
systems, this passive-negative feedback can reflect users' interests and serve
as an important supervision signal in extracting users' preferences. Therefore,
it is essential to carefully design and utilize it in this novel recommendation
scenario. In this work, we first conduct analyses based on a large-scale
real-world short-video behavior dataset and illustrate the significance of
leveraging passive feedback. We then propose a novel method that deploys the
sub-interest encoder, which incorporates positive feedback and passive-negative
feedback as supervision signals to learn the user's current active
sub-interest. Moreover, we introduce an adaptive fusion layer to integrate
various sub-interests effectively. To enhance the robustness of our model, we
then introduce a multi-task learning module to simultaneously optimize two
kinds of feedback -- passive-negative feedback and traditional randomly-sampled
negative feedback. The experiments on two large-scale datasets verify that the
proposed method can significantly outperform state-of-the-art approaches. The
code is released at https://github.com/tsinghua-fib-lab/RecSys2023-SINE.Comment: Accepted by RecSys'2
Where to Go Next for Recommender Systems? ID- vs. Modality-based Recommender Models Revisited
Recommendation models that utilize unique identities (IDs) to represent
distinct users and items have been state-of-the-art (SOTA) and dominated the
recommender systems (RS) literature for over a decade. Meanwhile, the
pre-trained modality encoders, such as BERT and ViT, have become increasingly
powerful in modeling the raw modality features of an item, such as text and
images. Given this, a natural question arises: can a purely modality-based
recommendation model (MoRec) outperforms or matches a pure ID-based model
(IDRec) by replacing the itemID embedding with a SOTA modality encoder? In
fact, this question was answered ten years ago when IDRec beats MoRec by a
strong margin in both recommendation accuracy and efficiency. We aim to revisit
this `old' question and systematically study MoRec from several aspects.
Specifically, we study several sub-questions: (i) which recommendation
paradigm, MoRec or IDRec, performs better in practical scenarios, especially in
the general setting and warm item scenarios where IDRec has a strong advantage?
does this hold for items with different modality features? (ii) can the latest
technical advances from other communities (i.e., natural language processing
and computer vision) translate into accuracy improvement for MoRec? (iii) how
to effectively utilize item modality representation, can we use it directly or
do we have to adjust it with new data? (iv) are there some key challenges for
MoRec to be solved in practical applications? To answer them, we conduct
rigorous experiments for item recommendations with two popular modalities,
i.e., text and vision. We provide the first empirical evidence that MoRec is
already comparable to its IDRec counterpart with an expensive end-to-end
training method, even for warm item recommendation. Our results potentially
imply that the dominance of IDRec in the RS field may be greatly challenged in
the future
NineRec: A Benchmark Dataset Suite for Evaluating Transferable Recommendation
Learning a recommender system model from an item's raw modality features
(such as image, text, audio, etc.), called MoRec, has attracted growing
interest recently. One key advantage of MoRec is that it can easily benefit
from advances in other fields, such as natural language processing (NLP) and
computer vision (CV). Moreover, it naturally supports transfer learning across
different systems through modality features, known as transferable recommender
systems, or TransRec.
However, so far, TransRec has made little progress, compared to
groundbreaking foundation models in the fields of NLP and CV. The lack of
large-scale, high-quality recommendation datasets poses a major obstacle. To
this end, we introduce NineRec, a TransRec dataset suite that includes a
large-scale source domain recommendation dataset and nine diverse target domain
recommendation datasets. Each item in NineRec is represented by a text
description and a high-resolution cover image. With NineRec, we can implement
TransRec models in an end-to-end training manner instead of using pre-extracted
invariant features. We conduct a benchmark study and empirical analysis of
TransRec using NineRec, and our findings provide several valuable insights. To
support further research, we make our code, datasets, benchmarks, and
leaderboards publicly available at https://github.com/westlake-repl/NineRec
Introducing a chaotic component in the control system of soil respiration
Chaos theory has been proved to be of great significance in a series of critical applications although, until now, its applications in analyzing soil respiration have not been addressed. This study aims to introduce a chaotic component in the control system of soil respiration and explain control complexity of this nonlinear chaotic system. This also presents a theoretical framework for better understanding chaotic components of soil respiration in arid land. A concept model of processes and mechanisms associated with subterranean CO2 evolution are developed, and dynamics of the chaotic system is characterized as an extended Riccati equation. Controls of soil respiration and kinetics of the chaotic system are interpreted and as a first attempt, control complexity of this nonlinear chaotic system is tackled by introducing a period-regulator in partitioning components of soil respiration
Exploring Adapter-based Transfer Learning for Recommender Systems: Empirical Studies and Practical Insights
Adapters, a plug-in neural network module with some tunable parameters, have
emerged as a parameter-efficient transfer learning technique for adapting
pre-trained models to downstream tasks, especially for natural language
processing (NLP) and computer vision (CV) fields. Meanwhile, learning
recommendation models directly from raw item modality features -- e.g., texts
of NLP and images of CV -- can enable effective and transferable recommender
systems (called TransRec). In view of this, a natural question arises: can
adapter-based learning techniques achieve parameter-efficient TransRec with
good performance?
To this end, we perform empirical studies to address several key
sub-questions. First, we ask whether the adapter-based TransRec performs
comparably to TransRec based on standard full-parameter fine-tuning? does it
hold for recommendation with different item modalities, e.g., textual RS and
visual RS. If yes, we benchmark these existing adapters, which have been shown
to be effective in NLP and CV tasks, in the item recommendation settings.
Third, we carefully study several key factors for the adapter-based TransRec in
terms of where and how to insert these adapters? Finally, we look at the
effects of adapter-based TransRec by either scaling up its source training data
or scaling down its target training data. Our paper provides key insights and
practical guidance on unified & transferable recommendation -- a less studied
recommendation scenario. We promise to release all code & datasets for future
research
MRI Lesion Load of Cerebral Small Vessel Disease and Cognitive Impairment in Patients With CADASIL
Background and objective: Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the best known and the most common monogenic small vessel disease (SVD). Cognitive impairment is an inevitable feature of CADASIL. Total SVD score and global cortical atrophy (GCA) scale were found to be good predictors of poor cognitive performance in community-dwelling adults. We aimed to estimate the association between the total SVD score, GCA scale and the cognitive performance in patients with CADASIL.Methods: We enrolled 20 genetically confirmed CADASIL patients and 20 controls matched by age, gender, and years of education. All participants underwent cognitive assessments to rate the global cognition and individual domain of executive function, information processing speed, memory, language, and visuospatial function. The total SVD score and GCA scale were rated.Results: The CADASIL group performed worse than the controls on all cognition measures. Neither global cognition nor any separate domain of cognition was significantly different among patients grouped by total SVD score. Negative correlations between the GCA score and cognitive performance were observed. Approximately 40% of the variance was explained by the total GCA score in the domains of executive function, information processing speed, and language. The superficial atrophy score was associated with poor performance in most of the domains of cognition. Adding the superficial atrophy score decreased the prediction power of the deep atrophy score on cognitive impairment alone.Conclusions: The GCA score, not the total SVD score, was significantly associated with poor cognitive performance in patients with CADASIL. Adding the superficial atrophy score attenuated the prediction power of the deep atrophy score on cognitive impairment alone
The complete mitochondrial genome of Pheropsophus occipitalis MacLeay, 1825 (Coleoptera: Carabidae)
Pheropsophus occipitalis MacLeay is a predatory enemy prey heavily on agricultural pests. The length of the complete mitochondrial genome of P. occipitalis was 16,800 bp with 20.4% GC content, including 41.2% A, 11.9% C, 8.4% G, 38.5% T. The genome encoded 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNA), two ribosomal RNA genes (rRNA). Phylogenetic analysis showed that P. occipitalis was clustered with Pheropsophus bimaculatus and Pheropsophus sobrinus. This study provided a scientific basis for the population genetics, phylogeny, and molecular taxonomy of P. occipitalis