52 research outputs found
A comparative study of ion diffusion during water imbibition in shale, sandstone and volcanic rock
Ā Ā Ā The recovered fracturing ļ¬uid is generally high in salinity (close to 200 kppm), which is related to the diffusion of salt ions from shale reservoir to the fracturing ļ¬uid. However, it is not clear about the diffusion capacity of salt ions in different types. In this paper, the shale, tight volcanic and sandstone are selected as comparative study and a series of tests are carried out for the porosity, permeability and mineral composition. The results show that the shale immersing in fracturing ļ¬uid will cause ions dissolution and diffusion, which will increase the salinity of the fracturing ļ¬uid. The solution salinity increases rapidly in the early stage and gradually slows down in the later stage. The salinity of the fracturing ļ¬uid has a linear relationship with the square root of time, so the slope of the curve can be used as a characteristic parameter to evaluate the ion diffusion rate. The process of dissolution and diffusion of salt ions will induce the expansion of micro-cracks, increasing the contact area between the fracturing ļ¬uid and shale and enhancing the solution salinity. The ion diffusion rate is positively related with the content of clay minerals and carbonate. The soluble ions include mainly SO42ā, Ca2+, Na+ and K+. The Na+ /Clā ratio is closely related to the content of clay minerals and carbonate minerals. It has a positive correlation with content of illite and chlorite, and a negative correlation with carbonate minerals, suggesting NaCl source from illite and chlorite. This study is signiļ¬cant for understanding the salinity characteristics of recovered fracturing ļ¬uid and evaluating the fracture network shape.Cited as: Yang, L., Chen, C., Liu, Y., Zheng, Y. A comparative study of ion diffusion during water imbibition in shale, sandstone and volcanic rock. Capillarity, 2020, 3(2): 16-27, doi: 10.46690/capi.2020.02.0
VertXNet: Automatic Segmentation and Identification of Lumbar and Cervical Vertebrae from Spinal X-ray Images
Manual annotation of vertebrae on spinal X-ray imaging is costly and
time-consuming due to bone shape complexity and image quality variations. In
this study, we address this challenge by proposing an ensemble method called
VertXNet, to automatically segment and label vertebrae in X-ray spinal images.
VertXNet combines two state-of-the-art segmentation models, namely U-Net and
Mask R-CNN to improve vertebrae segmentation. A main feature of VertXNet is to
also infer vertebrae labels thanks to its Mask R-CNN component (trained to
detect 'reference' vertebrae) on a given spinal X-ray image. VertXNet was
evaluated on an in-house dataset of lateral cervical and lumbar X-ray imaging
for ankylosing spondylitis (AS) patients. Our results show that VertXNet can
accurately label spinal X-rays (mean Dice of 0.9). It can be used to circumvent
the lack of annotated vertebrae without requiring human expert review. This
step is crucial to investigate clinical associations by solving the lack of
segmentation, a common bottleneck for most computational imaging projects
On-Device Domain Generalization
We present a systematic study of domain generalization (DG) for tiny neural
networks. This problem is critical to on-device machine learning applications
but has been overlooked in the literature where research has been merely
focused on large models. Tiny neural networks have much fewer parameters and
lower complexity and therefore should not be trained the same way as their
large counterparts for DG applications. By conducting extensive experiments, we
find that knowledge distillation (KD), a well-known technique for model
compression, is much better for tackling the on-device DG problem than
conventional DG methods. Another interesting observation is that the
teacher-student gap on out-of-distribution data is bigger than that on
in-distribution data, which highlights the capacity mismatch issue as well as
the shortcoming of KD. We further propose a method called out-of-distribution
knowledge distillation (OKD) where the idea is to teach the student how the
teacher handles out-of-distribution data synthesized via disruptive data
augmentation. Without adding any extra parameter to the model -- hence keeping
the deployment cost unchanged -- OKD significantly improves DG performance for
tiny neural networks in a variety of on-device DG scenarios for image and
speech applications. We also contribute a scalable approach for synthesizing
visual domain shifts, along with a new suite of DG datasets to complement
existing testbeds.Comment: Preprin
Towards automatic scoring of spinal x-ray for ankylosing spondylitis
Manually grading structural changes with the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) on spinal X-ray imaging is costly and timeconsuming due to bone shape complexity and image quality variations. In this study, we address this challenge by prototyping a 2-step auto-grading pipeline, called VertXGradeNet, to automatically predict mSASSS scores for the cervical and lumbar vertebral units (VUs) in X-ray spinal imaging. The VertXGradeNet utilizes VUs generated by our previously developed VU extraction pipeline (VertXNet) as input and predicts mSASSS based on those VUs. VertXGradeNet was evaluated on an in-house dataset of lateral cervical and lumbar X-ray images for axial spondylarthritis patients. Our results show that VertXGradeNet can predict the mSASSS score for each VU when the data is limited in quantity and imbalanced. Overall, it can achieve a balanced accuracy of 0.56 and 0.51 for 4 different mSASSS scores (i.e., a score of 0, 1, 2, 3) on two test datasets. The accuracy of the presented method shows the potential to streamline the spinal radiograph readings and therefore reduce the cost of future clinical trials
VertXNet: an ensemble method for vertebral body segmentation and identification from cervical and lumbar spinal X-rays
Accurate annotation of vertebral bodies is crucial for automating the analysis of spinal X-ray images. However, manual annotation of these structures is a laborious and costly process due to their complex nature, including small sizes and varying shapes. To address this challenge and expedite the annotation process, we propose an ensemble pipeline called VertXNet. This pipeline currently combines two segmentation mechanisms, semantic segmentation using U-Net, and instance segmentation using Mask R-CNN, to automatically segment and label vertebral bodies in lateral cervical and lumbar spinal X-ray images. VertXNet enhances its effectiveness by adopting a rule-based strategy (termed the ensemble rule) for effectively combining segmentation outcomes from U-Net and Mask R-CNN. It determines vertebral body labels by recognizing specific reference vertebral instances, such as cervical vertebra 2 (āC2ā) in cervical spine X-rays and sacral vertebra 1 (āS1ā) in lumbar spine X-rays. Those references are commonly relatively easy to identify at the edge of the spine. To assess the performance of our proposed pipeline, we conducted evaluations on three spinal X-ray datasets, including two in-house datasets and one publicly available dataset. The ground truth annotations were provided by radiologists for comparison. Our experimental results have shown that the proposed pipeline outperformed two state-of-the-art (SOTA) segmentation models on our test dataset with a mean Dice of 0.90, vs. a mean Dice of 0.73 for Mask R-CNN and 0.72 for U-Net. We also demonstrated that VertXNet is a modular pipeline that enables using other SOTA model, like nnU-Net to further improve its performance. Furthermore, to evaluate the generalization ability of VertXNet on spinal X-rays, we directly tested the pre-trained pipeline on two additional datasets. A consistently strong performance was observed, with mean Dice coefficients of 0.89 and 0.88, respectively. In summary, VertXNet demonstrated significantly improved performance in vertebral body segmentation and labeling for spinal X-ray imaging. Its robustness and generalization were presented through the evaluation of both in-house clinical trial data and publicly available datasets
Case report: Two cases of Poirier-Bienvenu neurodevelopmental syndrome and review of literature
The Poirier-Bienvenu neurodevelopmental syndrome (POBINDS) is a rare disease caused by mutations in the CSNK2B gene, which is characterized by intellectual disability and early-onset epilepsy. Mosaicism has not been previously reported in CSNK2B gene. POBINDS is autosomal dominant and almost all reported cases were de novo variants. Here, we report two patients were diagnosed with POBINDS. Using Whole Exome Sequencing (WES), we detected two novel CSNK2B variants in the two unrelated individuals: c.634_635del (p.Lys212AspfsTer33) and c.142Cā>āT (p.Gln48Ter) respectively. Both of them showed mild developmental delay with early-onset and clustered seizures. The patient with c.634_635del(p.Lys212AspfsTer33) variant was mutant mosaicism, and the proportion of alleles in peripheral blood DNA was 28%. Further, the literature of patients with a de novo mutation of the CSNK2B gene was reviewed, particularly seizure semiology and genotype-phenotype correlations
Crosstalk Between Autophagy and Cerebral Ischemia
With the use of advanced electron microscopy and molecular biology tools, several studies have shown that autophagy is involved in the development of ischemic stroke. A series of molecular mechanisms are involved in the regulation of autophagy. In this work, the possible molecular mechanisms involved in autophagy during ischemic stroke were reviewed and new potential targets for the study and treatment of ischemic stroke were provided
MMBench: Is Your Multi-modal Model an All-around Player?
Large vision-language models have recently achieved remarkable progress,
exhibiting great perception and reasoning abilities concerning visual
information. However, how to effectively evaluate these large vision-language
models remains a major obstacle, hindering future model development.
Traditional benchmarks like VQAv2 or COCO Caption provide quantitative
performance measurements but suffer from a lack of fine-grained ability
assessment and non-robust evaluation metrics. Recent subjective benchmarks,
such as OwlEval, offer comprehensive evaluations of a model's abilities by
incorporating human labor, but they are not scalable and display significant
bias. In response to these challenges, we propose MMBench, a novel
multi-modality benchmark. MMBench methodically develops a comprehensive
evaluation pipeline, primarily comprised of two elements. The first element is
a meticulously curated dataset that surpasses existing similar benchmarks in
terms of the number and variety of evaluation questions and abilities. The
second element introduces a novel CircularEval strategy and incorporates the
use of ChatGPT. This implementation is designed to convert free-form
predictions into pre-defined choices, thereby facilitating a more robust
evaluation of the model's predictions. MMBench is a systematically-designed
objective benchmark for robustly evaluating the various abilities of
vision-language models. We hope MMBench will assist the research community in
better evaluating their models and encourage future advancements in this
domain. Project page: https://opencompass.org.cn/mmbench
VBench: Comprehensive Benchmark Suite for Video Generative Models
Video generation has witnessed significant advancements, yet evaluating these
models remains a challenge. A comprehensive evaluation benchmark for video
generation is indispensable for two reasons: 1) Existing metrics do not fully
align with human perceptions; 2) An ideal evaluation system should provide
insights to inform future developments of video generation. To this end, we
present VBench, a comprehensive benchmark suite that dissects "video generation
quality" into specific, hierarchical, and disentangled dimensions, each with
tailored prompts and evaluation methods. VBench has three appealing properties:
1) Comprehensive Dimensions: VBench comprises 16 dimensions in video generation
(e.g., subject identity inconsistency, motion smoothness, temporal flickering,
and spatial relationship, etc). The evaluation metrics with fine-grained levels
reveal individual models' strengths and weaknesses. 2) Human Alignment: We also
provide a dataset of human preference annotations to validate our benchmarks'
alignment with human perception, for each evaluation dimension respectively. 3)
Valuable Insights: We look into current models' ability across various
evaluation dimensions, and various content types. We also investigate the gaps
between video and image generation models. We will open-source VBench,
including all prompts, evaluation methods, generated videos, and human
preference annotations, and also include more video generation models in VBench
to drive forward the field of video generation.Comment: Equal contributions from first four authors. Project page:
https://vchitect.github.io/VBench-project/ Code:
https://github.com/Vchitect/VBenc
Application of Angiotensin ReceptorāNeprilysin Inhibitor in Chronic Kidney Disease Patients: Chinese Expert Consensus
Chronic kidney disease (CKD) is a global public health problem, and cardiovascular disease is the most common cause of death in patients with CKD. The incidence and prevalence of cardiovascular events during the early stages of CKD increases significantly with a decline in renal function. More than 50% of dialysis patients die from cardiovascular disease, including coronary heart disease, heart failure, arrhythmia, and sudden cardiac death. Therefore, developing effective methods to control risk factors and improve prognosis is the primary focus during the diagnosis and treatment of CKD. For example, the SPRINT study demonstrated that CKD drugs are effective in reducing cardiovascular and cerebrovascular events by controlling blood pressure. Uncontrolled blood pressure not only increases the risk of these events but also accelerates the progression of CKD. A co-crystal complex of sacubitril, which is a neprilysin inhibitor, and valsartan, which is an angiotensin receptor blockade, has the potential to be widely used against CKD. Sacubitril inhibits neprilysin, which further reduces the degradation of natriuretic peptides and enhances the beneficial effects of the natriuretic peptide system. In contrast, valsartan alone can block the angiotensin II-1 (AT1) receptor and therefore inhibit the renināangiotensināaldosterone system. These two components can act synergistically to relax blood vessels, prevent and reverse cardiovascular remodeling, and promote natriuresis. Recent studies have repeatedly confirmed that the first and so far the only angiotensin receptorāneprilysin inhibitor (ARNI) sacubitril/valsartan can reduce blood pressure more effectively than renināangiotensin system inhibitors and improve the prognosis of heart failure in patients with CKD. Here, we propose clinical recommendations based on an expert consensus to guide ARNI-based therapeutics and reduce the occurrence of cardiovascular events in patients with CKD
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