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421.
张德祥
(2023-05-16 08:14):
#paper https://doi.org/10.48550/arXiv.2203.11740
我们可以把我们的大脑想象成是地球,地心熔岩的产生如同在海马体的短期记忆的发生,过程是量子的;地表的地震因为势能释放,选出强的短期记忆成为长期记忆存储在不同皮层的记忆印记细胞能被释放。
AI+脑科学+量子力学的结合。我们提出了PNN,但它不仅仅是简单的时间序列模型。
除了突触连接的共享权重,我们提出了新的神经网络包括突触有效范围权重也会进行前向和反向计算。而且很多仿真是RNN无法实现的。
正向和负向记忆的大脑塑性是量子的并产生短期记忆,并且波函数展现出在一段时间表现出指数衰减,在海马体里产生。而指数衰减是因为壁垒,壁垒可能和星形胶质细胞有关。工作记忆的大脑塑性在大脑流动从海马体到不同皮层通过方向导数。强的工作记忆的大脑塑性转变成长期记忆也就是最大的方向导数,而最大的方向导数就是梯度。这样长期记忆是工作记忆的大脑塑性的梯度。短期记忆变成长期记忆的过程,也就是非经典力学变成经典力学的过程。
PNN的仿真符合了6篇正刊、6篇子刊和1篇物理顶刊的脑科学实验和假设。
更多可以参考: https://mp.weixin.qq.com/s/k-KD1KcQo9FiYcQvSypBjQ
arXiv,
2022.
DOI: 10.48550/arXiv.2203.11740
Abstract:
In addition to the shared weights of the synaptic connections, we proposed a new neural network that includes the synaptic effective range weights for both the forward and back propagation. …
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In addition to the shared weights of the synaptic connections, we proposed a new neural network that includes the synaptic effective range weights for both the forward and back propagation. And lots of simulations were used which RNN cannot be achieved. The simulations of PNN fit very well in experiments and hypotheses of 6 papers CNS Journals, 6 papers of CNS family Journals and 1 paper top Physics Journal [14-26]. The brain plasticity in positive or negative memory may be quantum and produce short-term memory, and exhibits an exponential decay in the wave function over a period of time, produced in the hippocampus. And exponential decay occurs due to barriers, and barriers can refer to astrocytes. Brain plasticity in working memory flows through the brain, from the hippocampus to the cortex, through directional derivatives. The strong working memory brain plasticity turns to long-term memory means maximum of directional derivatives, and maximum of directional derivatives is gradient. Thus, long-term memory signifies the gradient of brain plasticity in working memory. The process of short-term memory turns to long-term memory is the process of non-classically turns to classically. Astrocytic cortex memory persistence factor also inhibits local synaptic accumulation, and the model inspires experiments. This could be the process of astrocytes phagocytose synapses is driven by both positive and negative memories of plasticity in the brain. In simulation, it is possible that thicker cortices and more diverse individuals within the brain could have high IQ, but thickest cortices and most diverse individuals may have low IQ in simulation. PSO considers global solution or best previous solution, but also considers relatively good and relatively inferior solution. And PNN modified ResNet to consider memory gradient. The simple PNN only considers astrocytes phagocytosed synapses.
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422.
姗姗来迟
(2023-05-14 19:34):
#paper Multimodal Graph Transformer for Multimodal Question Answering
https://arxiv.org/abs/2305.00581
这项工作从这两个世界中受益,并提出了一种新的多模态图转换器,用于需要跨多模态执行推理的问答任务。引入了一种涉及图形的即插即用类注意机制,将从文本和视觉数据中获得的多模态图形信息作为有效的先验信息整合到vanilla自注意力中。
具体来说,文章构建文本图、密集区域图和语义图来生成邻接矩阵,然后将它们与输入的视觉和语言特征组合在一起进行下游推理。
学习笔记链接:https://blog.csdn.net/weixin_44845357/article/details/130577459?csdn_share_tail=%7B%22type%22%3A%22blog%22%2C%22rType%22%3A%22article%22%2C%22rId%22%3A%22130577459%22%2C%22source%22%3A%22weixin_44845357%22%7D
arXiv,
2023.
DOI: 10.48550/arXiv.2305.00581
Abstract:
Despite the success of Transformer models in vision and language tasks, they often learn knowledge from enormous data implicitly and cannot utilize structured input data directly. On the other hand, …
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Despite the success of Transformer models in vision and language tasks, they often learn knowledge from enormous data implicitly and cannot utilize structured input data directly. On the other hand, structured learning approaches such as graph neural networks (GNNs) that integrate prior information can barely compete with Transformer models. In this work, we aim to benefit from both worlds and propose a novel Multimodal Graph Transformer for question answering tasks that requires performing reasoning across multiple modalities. We introduce a graph-involved plug-and-play quasi-attention mechanism to incorporate multimodal graph information, acquired from text and visual data, to the vanilla self-attention as effective prior. In particular, we construct the text graph, dense region graph, and semantic graph to generate adjacency matrices, and then compose them with input vision and language features to perform downstream reasoning. Such a way of regularizing self-attention with graph information significantly improves the inferring ability and helps align features from different modalities. We validate the effectiveness of Multimodal Graph Transformer over its Transformer baselines on GQA, VQAv2, and MultiModalQA datasets.
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423.
颜林林
(2023-05-11 22:05):
#paper doi:10.3389/fneur.2023.1036453 Frontiers in Neurology, 2023, Mechanism of Qihuang needle therapy in the management of tic disorders: a clinical trial protocol. 这是一篇关于针灸治疗方法开展注册临床试验的文章(在中国临床试验注册中心注册,编号:ChiCTR2200057723,网址:https://www.chictr.org.cn/showproj.html?proj=161252)。该临床试验于2022年3月至2023年9月期间开展,通过岐黄针对抽动障碍的儿童进行干预性治疗(预计入组干预组和对照组各20例),并随访患儿12周,除相关临床量表评估外,还采集外周血并通过质谱和ELISA实验测定其血浆中的代谢物和蛋白,以及采集粪便进行16S rRNA的微生物组分析,以期通过这些多组学数据来探索针灸治疗的作用机制。临床试验尚未结束,本文的投稿时间为2022年9月(历经半年至2023年4月接收),为提前公开详细披露其临床试验具体操作流程,因此仅有方法描述,而无结果数据。虽然很难想象代谢物、蛋白及肠道菌群等信息,要与针灸对神经类疾病治疗的作用机制该如何关联,但中医讲究整体系统论,万事万物皆有联系,既然在肉眼可见的解剖学水平难以建立直接联系,那间接通过不同多组学的尝试来观察和早期探索,或许也是一种不错的尝试。先期待下临床试验完成后的数据分析结果的公开发表吧。
Abstract:
Background: Qihuang needle therapy is a newly developed acupuncture therapy to treat tic disorders in clinical practice. However, the mechanism to reduce tic severity remains unknown. Changes in intestinal flora …
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Background: Qihuang needle therapy is a newly developed acupuncture therapy to treat tic disorders in clinical practice. However, the mechanism to reduce tic severity remains unknown. Changes in intestinal flora and circulation metabolites are perhaps the potential pathogenesis of tic disorders. As a result, we present a protocol for a controlled clinical trial using multi-omics analysis to probe the mechanism of the Qihuang needle in managing tic disorders.Methods: This is a matched-pairs design, controlled, clinical trial for patients with tic disorders. Participants will be allocated to either an experimental group or a healthy control group. The main acupoints are Baihui (GV20), Yintang (EX-HN3), and Jueyinshu (BL14). The experimental group will receive Qihuang needle therapy for a month, while the control group will receive no interventions.Expected outcomes: The change in the severity of the tic disorder is set as the main outcome. Secondary outcomes include gastrointestinal severity index and recurrence rate, which will be calculated after a 12-week follow-up. Gut microbiota, measured by 16S rRNA gene sequencing; serum metabolomics, assessed via LC/MS; and serum zonulin, assessed by enzyme-linked immunosorbent assay (ELISA), will be used as biological specimen analysis outcomes. The present study will investigate the possible interactions between intestinal flora and serum metabolites and the improvement of clinical profiles, which may elucidate the mechanism of Qihuang needle therapy for tic disorders.Trial registration: This trial is registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/). Registration number: ChiCTR2200057723, Date: 2022-04-14.
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424.
AI 5.0.3
(2023-05-08 17:03):
#paper Systematic Integration of Structural and Functional Data into Multi-scale Models of Mouse Primary Visual Cortex,https://doi.org/10.1016/j.neuron.2020.01.040,本文借助bmtk建模工具对视觉皮层v1区进行建模计算提出了生物学模型和计算机拓扑模型,主要分为生物学成分模型和整合发射点神经元模型,有较好的迁移性可以使用在其他脑区建模上。
Abstract:
Structural rules underlying functional properties of cortical circuits are poorly understood. To explore these rules systematically, we integrated information from extensive literature curation and large-scale experimental surveys into a data-driven, …
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Structural rules underlying functional properties of cortical circuits are poorly understood. To explore these rules systematically, we integrated information from extensive literature curation and large-scale experimental surveys into a data-driven, biologically realistic simulation of the awake mouse primary visual cortex. The model was constructed at two levels of granularity, using either biophysically detailed or point neurons. Both variants have identical network connectivity and were compared to each other and to experimental recordings of visual-driven neural activity. While tuning these networks to recapitulate experimental data, we identified rules governing cell-class-specific connectivity and synaptic strengths. These structural constraints constitute hypotheses that can be tested experimentally. Despite their distinct single-cell abstraction, both spatially extended and point models perform similarly at the level of firing rate distributions for the questions we investigated. All data and models are freely available as a resource for the community.
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425.
颜林林
(2023-05-06 00:47):
#paper doi:10.1056/NEJMoa2212856 The New England Journal of Medicine, 2023, Interrupting Endocrine Therapy to Attempt Pregnancy after Breast Cancer. 乳腺癌患者在接受手术后,若为HR阳性,则会继续开展数年的内分泌辅助治疗,以巩固和改善疗效,避免和降低疾病复发。在辅助治疗期间,患者若打算怀孕生娃,则需要停止原定的内分泌治疗,这是否会导致严重的负面影响,尚无明确结论。这篇研究就是针对此情况开展的注册临床试验(NCT02308085),入组了2014至2019年期间符合条件的518位患者,她们都因怀孕计划中断了内分泌治疗,对她们进行持续随访,分析其乳腺癌复发事件及生育情况。目前已达到次要终点,复发事件数未超过预定安全阈值,数据进行锁定和分析。与外部一个1499例的未中断内分泌治疗的乳腺癌队列进行对比,复发事件的发生率并无明显区别。初步支持为尝试怀孕而暂停治疗不会产生明显的短期负面影响。对这些患者的随访还在继续,以便未来对相应产生的长期影响做出评估和结论。
Abstract:
BACKGROUND: Prospective data on the risk of recurrence among women with hormone receptor-positive early breast cancer who temporarily discontinue endocrine therapy to attempt pregnancy are lacking.METHODS: We conducted a single-group …
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BACKGROUND: Prospective data on the risk of recurrence among women with hormone receptor-positive early breast cancer who temporarily discontinue endocrine therapy to attempt pregnancy are lacking.METHODS: We conducted a single-group trial in which we evaluated the temporary interruption of adjuvant endocrine therapy to attempt pregnancy in young women with previous breast cancer. Eligible women were 42 years of age or younger; had had stage I, II, or III disease; had received adjuvant endocrine therapy for 18 to 30 months; and desired pregnancy. The primary end point was the number of breast cancer events (defined as local, regional, or distant recurrence of invasive breast cancer or new contralateral invasive breast cancer) during follow-up. The primary analysis was planned to be performed after 1600 patient-years of follow-up. The prespecified safety threshold was the occurrence of 46 breast cancer events during this period. Breast cancer outcomes in this treatment-interruption group were compared with those in an external control cohort consisting of women who would have met the entry criteria for the current trial.RESULTS: Among 516 women, the median age was 37 years, the median time from breast cancer diagnosis to enrollment was 29 months, and 93.4% had stage I or II disease. Among 497 women who were followed for pregnancy status, 368 (74.0%) had at least one pregnancy and 317 (63.8%) had at least one live birth. In total, 365 babies were born. At 1638 patient-years of follow-up (median follow-up, 41 months), 44 patients had a breast cancer event, a result that did not exceed the safety threshold. The 3-year incidence of breast cancer events was 8.9% (95% confidence interval [CI], 6.3 to 11.6) in the treatment-interruption group and 9.2% (95% CI, 7.6 to 10.8) in the control cohort.CONCLUSIONS: Among select women with previous hormone receptor-positive early breast cancer, temporary interruption of endocrine therapy to attempt pregnancy did not confer a greater short-term risk of breast cancer events, including distant recurrence, than that in the external control cohort. Further follow-up is critical to inform longer-term safety. (Funded by ETOP IBCSG Partners Foundation and others; POSITIVE ClinicalTrials.gov number, NCT02308085.).
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426.
AI 5.0.3
(2023-04-30 23:59):
#paper A distributed and efficient population code of mixed selectivity neurons for flexible navigation decisions https://doi.org/10.1038/s41467-023-37804-2 这篇文章研究了虚拟导航背后皮层区域和神经活动模式,根据不同线索匹配切换不同导航策略,通过编码电流和记忆视觉提示混合介导导航开关,提供导航决策灵活性。
Abstract:
Decision-making requires flexibility to rapidly switch one's actions in response to sensory stimuli depending on information stored in memory. We identified cortical areas and neural activity patterns underlying this flexibility …
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Decision-making requires flexibility to rapidly switch one's actions in response to sensory stimuli depending on information stored in memory. We identified cortical areas and neural activity patterns underlying this flexibility during virtual navigation, where mice switched navigation toward or away from a visual cue depending on its match to a remembered cue. Optogenetics screening identified V1, posterior parietal cortex (PPC), and retrosplenial cortex (RSC) as necessary for accurate decisions. Calcium imaging revealed neurons that can mediate rapid navigation switches by encoding a mixture of a current and remembered visual cue. These mixed selectivity neurons emerged through task learning and predicted the mouse's choices by forming efficient population codes before correct, but not incorrect, choices. They were distributed across posterior cortex, even V1, and were densest in RSC and sparsest in PPC. We propose flexibility in navigation decisions arises from neurons that mix visual and memory information within a visual-parietal-retrosplenial network.
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427.
半面阳光
(2023-04-30 23:55):
#paper DOI: 10.1038/s41436-019-0467-4, Genet Med. 2019, Clinical utility of noninvasive prenatal screening for expanded chromosome disease syndromes. 这篇文章研究了无创产前检测(NIPT)用于拷贝数变异检测的检测能力。这一研究征集了9万多名孕妇外周血样本,进行了拓展性NIPT检测。研究结果显示,拓展性NIPT在检测常见的染色体非整体时的检出效果更佳,对于拷贝数变异具有一定的检出能力。总体上看,拓展性NIPT对产前染色体异常检测的检出效果由于常规的NIPT。
IF:6.600Q1
Genetics in medicine : official journal of the American College of Medical Genetics,
2019-09.
DOI: 10.1038/s41436-019-0467-4
PMID: 30828085
Abstract:
PURPOSE: To assess the clinical performance of an expanded noninvasive prenatal screening (NIPS) test ("NIPS-Plus") for detection of both aneuploidy and genome-wide microdeletion/microduplication syndromes (MMS).METHODS: A total of 94,085 women …
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PURPOSE: To assess the clinical performance of an expanded noninvasive prenatal screening (NIPS) test ("NIPS-Plus") for detection of both aneuploidy and genome-wide microdeletion/microduplication syndromes (MMS).METHODS: A total of 94,085 women with a singleton pregnancy were prospectively enrolled in the study. The cell-free plasma DNA was directly sequenced without intermediate amplification and fetal abnormalities identified using an improved copy-number variation (CNV) calling algorithm.RESULTS: A total of 1128 pregnancies (1.2%) were scored positive for clinically significant fetal chromosome abnormalities. This comprised 965 aneuploidies (1.026%) and 163 (0.174%) MMS. From follow-up tests, the positive predictive values (PPVs) for T21, T18, T13, rare trisomies, and sex chromosome aneuploidies were calculated as 95%, 82%, 46%, 29%, and 47%, respectively. For known MMS (n = 32), PPVs were 93% (DiGeorge), 68% (22q11.22 microduplication), 75% (Prader-Willi/Angleman), and 50% (Cri du Chat). For the remaining genome-wide MMS (n = 88), combined PPVs were 32% (CNVs ≥10 Mb) and 19% (CNVs <10 Mb).CONCLUSION: NIPS-Plus yielded high PPVs for common aneuploidies and DiGeorge syndrome, and moderate PPVs for other MMS. Our results present compelling evidence that NIPS-Plus can be used as a first-tier pregnancy screening method to improve detection rates of clinically significant fetal chromosome abnormalities.
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428.
Ricardo
(2023-04-30 23:45):
#paper Pancreatic Cancer Detection on CT Scans with Deep Learning: A Nationwide Population-based Study https://doi.org/10.1148/radiol.220152 正好最近要写一篇和医院合作的腹腔影像的论文,所以最近看了一些这方面的论文。这篇论文的合作者回顾性收集了2006年1月至2018年7月期间诊断为胰腺癌的患者的对比增强CT研究与2004年1月至2019年12月期间获得的正常胰腺个体(对照组)的CT研究进行了比较。开发了包含分割卷积神经网络(CNN)和集成五个CNN的分类器的端到端工具,并在内部测试集和全国范围内的验证集中进行了验证。546例胰腺癌患者(平均年龄65岁6 12岁[SD],男性297例)和733例对照者随机分为训练组、验证组和测试组。在内部测试集中,DL工具达到89.9% (98 / 109;95% CI: 82.7, 94.9)敏感性95.9% (141 / 147;95% CI: 91.3, 98.5)特异性(受试者工作特征曲线下面积[AUC], 0.96;95% CI: 0.94, 0.99),敏感性与原始放射科医生报告相比无显著差异(P = 0.11) (96.1% [98 / 102];95% ci: 90.3, 98.9)。在台湾各机构的1473个真实CT研究(669个恶性研究,804个对照研究)的测试集中,DL工具区分CT恶性研究和对照研究的准确率为89.7%(669个中的600个;95% CI: 87.1, 91.9)敏感性和92.8%特异性(746 / 804;95% ci: 90.8, 94.5) (auc, 0.95;95% CI: 0.94, 0.96), 74.7% (68 / 91;95% CI: 64.5, 83.3)对小于2cm的恶性肿瘤的敏感性。
Abstract:
Background Approximately 40% of pancreatic tumors smaller than 2 cm are missed at abdominal CT. Purpose To develop and to validate a deep learning (DL)-based tool able to detect pancreatic …
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Background Approximately 40% of pancreatic tumors smaller than 2 cm are missed at abdominal CT. Purpose To develop and to validate a deep learning (DL)-based tool able to detect pancreatic cancer at CT. Materials and Methods Retrospectively collected contrast-enhanced CT studies in patients diagnosed with pancreatic cancer between January 2006 and July 2018 were compared with CT studies of individuals with a normal pancreas (control group) obtained between January 2004 and December 2019. An end-to-end tool comprising a segmentation convolutional neural network (CNN) and a classifier ensembling five CNNs was developed and validated in the internal test set and a nationwide real-world validation set. The sensitivities of the computer-aided detection (CAD) tool and radiologist interpretation were compared using the McNemar test. Results A total of 546 patients with pancreatic cancer (mean age, 65 years ± 12 [SD], 297 men) and 733 control subjects were randomly divided into training, validation, and test sets. In the internal test set, the DL tool achieved 89.9% (98 of 109; 95% CI: 82.7, 94.9) sensitivity and 95.9% (141 of 147; 95% CI: 91.3, 98.5) specificity (area under the receiver operating characteristic curve [AUC], 0.96; 95% CI: 0.94, 0.99), without a significant difference ( = .11) in sensitivity compared with the original radiologist report (96.1% [98 of 102]; 95% CI: 90.3, 98.9). In a test set of 1473 real-world CT studies (669 malignant, 804 control) from institutions throughout Taiwan, the DL tool distinguished between CT malignant and control studies with 89.7% (600 of 669; 95% CI: 87.1, 91.9) sensitivity and 92.8% specificity (746 of 804; 95% CI: 90.8, 94.5) (AUC, 0.95; 95% CI: 0.94, 0.96), with 74.7% (68 of 91; 95% CI: 64.5, 83.3) sensitivity for malignancies smaller than 2 cm. Conclusion The deep learning-based tool enabled accurate detection of pancreatic cancer on CT scans, with reasonable sensitivity for tumors smaller than 2 cm. © RSNA, 2022 See also the editorial by Aisen and Rodrigues in this issue.
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429.
彬
(2023-04-30 23:36):
#paper Fractionation of κ-casein from caprine micellar caseins using differential precipitation. https://doi.org/10.1016/j.idairyj.2023.105677. 江南大学食品科学与技术国家重点实验室等的Luo Guixin, Liu Xiaoming, Liu Dasong*, Zhou Peng等系统研究从山羊乳胶束酪蛋白浓缩物(micellar casein concentrate,MCC)中差异沉淀获得κ-酪蛋白的主要步骤中潜在关键加工条件的影响,还研究了酪蛋白浓度对κ-酪蛋白分馏的影响,旨在提高扩大条件下的加工能力。使用差异沉淀法对κ-酪蛋白进行分馏是基于单个酪蛋白在碱性pH值条件下对过量添加Ca的不同亲和力,然后进行中和,以促进αs-酪蛋白和β-酪蛋白的选择性沉淀。为提高从山羊乳MCC中分离的κ-酪蛋白产量和纯度,对每个主要步骤中的主要加工变量条件依次进行优化,得到最佳条件为:在pH 11.0条件下,使用匀浆再水合MCC(含3%酪蛋白),然后解离胶束;添加45 mmol/L Ca在25 ℃条件下络合酪蛋白60 min,然后使用2 mol/L乙酸在pH 7.0、25 ℃条件下再次沉淀β-/αs-酪蛋白60 min;使用2 个分馏循环,在第2个循环中添加50 mmol/L Ca,然后在pH 3.8、50 ℃条件下沉淀κ-酪蛋白。为提高扩大条件下的加工能力,将酪蛋白浓度提高4%~7%,同时添加60 mmol/L Ca,可获得与最佳条件下相当的κ-酪蛋白产量和纯度。在酪蛋白含量为4%时,MCC分散体中κ-酪蛋白的最大产量和纯度分别为84.6%和84.4%。
Abstract:
The effects of potentially important processing conditions at each step of differential precipitation on the yield and purity of κ-casein fractionated from caprine micellar casein concentrate (MCC) were investigated. The …
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The effects of potentially important processing conditions at each step of differential precipitation on the yield and purity of κ-casein fractionated from caprine micellar casein concentrate (MCC) were investigated. The optimal conditions were: rehydrating (3% casein) MCC using homogenisation followed by dissociating micelles at pH 11.0; complexing caseins using 45 mm added Ca at 25 °C for 60 min, followed by precipitating β-/αS-caseins using 2 m acetic acid at pH 7.0 again at 25 °C for 60 min. Two fractionation cycles were used with 50 mm added Ca for the second cycle, followed by precipitating κ-casein at pH 3.8 and 50 °C. To increase processing capacity for scale-up, increased casein concentrations of 4–7% along with 60 mm added Ca resulted in comparable yields and purity of the κ-casein. Maximum yield and purity of 84.6% and 84.4%, respectively, were achieved for κ-casein from the MCC dispersions at 4% casein.
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430.
林海onrush
(2023-04-30 23:31):
#paper,Tensor Decompositions and Applications∗,DOI: 10.1137/07070111X,张量分解在诸多领域都有深入的尝试,高阶张量(即N≥3的N路数组)在心理测量学、化学计量学、信号处理、数值线性代数、计算机视觉、数值分析、数据挖掘、神经科学、图分析和其他方面均有应用。这篇paper讲述了张量运算的基础,对张量的运算基础进行了详细的探讨,我认为非常有学习价值,未来会在很多行业的发展上具有重大贡献。
Abstract:
This survey provides an overview of higher-order tensor decompositions, their applications, and available software. A tensor is a multidimensional or N-way array. Decompositions of higher-order tensors (i.e., N-way arrays with …
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This survey provides an overview of higher-order tensor decompositions, their applications, and available software. A tensor is a multidimensional or N-way array. Decompositions of higher-order tensors (i.e., N-way arrays with N≥3) have applications in psycho-metrics, chemometrics, signal processing, numerical linear algebra, computer vision, numerical analysis, data mining, neuroscience, graph analysis, and elsewhere. Two particular tensor decompositions can be considered to be higher-order extensions of the matrix singular value decomposition: CANDECOMP/PARAFAC (CP) decomposes a tensor as a sum of rank-one tensors, and the Tucker decomposition is a higher-order form of principal component analysis. There are many other tensor decompositions, including INDSCAL, PARAFAC2, CANDELINC, DEDICOM, and PARATUCK2 as well as nonnegative variants of all of the above. The N-way Toolbox, Tensor Toolbox, and Multilinear Engine are examples of software packages for working with tensors.
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431.
笑对人生
(2023-04-30 23:23):
#paper doi: 10.1038/s41591-023-02221-x. Comitani F, et al. Diagnostic classification of childhood cancer using multiscale transcriptomics. Nat Med. 2023 Mar;29(3):656-666.
研究背景:世界每年新增的儿童肿瘤患者大约40万。与成年人癌症不同的是,儿童肿瘤大多起源于胚胎组织,并且影响肿瘤发展的细胞类型是不同的。白血病是一种多发于儿童的肿瘤,比例约占1/3。再如,神经母细胞瘤,是一种高度异质性癌症,可始于婴儿和在儿童或青少年期间出现恶性进展,但少见于成年人。目前,尚未发现能用于所有儿童肿瘤诊断的全面分子生物标志物。转录组测序不仅能反映肿瘤的表达谱特征,而且可以能发现独立于基因组的肿瘤间差异。大多数已建立的转录组测序分类模型都是需要预标的有监督工具,因此难以发现一些复杂的表型变化。此外,瘤内异质性和肿瘤基质或免疫细胞浸润存在可能会导致在同一种肿瘤同时存在预后不良和预后良好的生物标志物。综上,有必要寻找以转录组测序为基础、灵活性高和适用于所有儿童肿瘤的生物标志物。
样本类型:聚类用数据集:2,178份儿童肿瘤样本、9,400成人肿瘤和1,735非癌组织。神经母细胞瘤转录可塑性验证样本8份。
数据类型:RNAseq和scRNAseq
研究主要内容:基于RNAseq建立一种名为RACCOON的自适应聚类方法,该方法能实现对肿瘤亚型进行无监督分类。通过比较不同类群的特征,发现儿童和成年肿瘤因年龄不同明显的差异,并且发现儿童转录紊乱性更高。接着研究者开发了一个名为OTTER的集成CNN分类器,并以RACCOON的聚类结果作为输入。与任何单一模型和以往发表的分类器相比,OTTER在所有指标上都表现更为优秀,并能高精确地对儿童肿瘤样本进行癌种类型、癌与非癌和亚型进行分类。更令人惊讶的是,该分类管道在低肿瘤纯度、高技术噪音和低测序深度(几百万个reads)下,仍能保持较高的准确度。总而言之,该研究提供了一个适用儿童肿瘤的通用分类器,并有望应用于其他的癌症类型。
Abstract:
The causes of pediatric cancers' distinctiveness compared to adult-onset tumors of the same type are not completely clear and not fully explained by their genomes. In this study, we used …
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The causes of pediatric cancers' distinctiveness compared to adult-onset tumors of the same type are not completely clear and not fully explained by their genomes. In this study, we used an optimized multilevel RNA clustering approach to derive molecular definitions for most childhood cancers. Applying this method to 13,313 transcriptomes, we constructed a pediatric cancer atlas to explore age-associated changes. Tumor entities were sometimes unexpectedly grouped due to common lineages, drivers or stemness profiles. Some established entities were divided into subgroups that predicted outcome better than current diagnostic approaches. These definitions account for inter-tumoral and intra-tumoral heterogeneity and have the potential of enabling reproducible, quantifiable diagnostics. As a whole, childhood tumors had more transcriptional diversity than adult tumors, maintaining greater expression flexibility. To apply these insights, we designed an ensemble convolutional neural network classifier. We show that this tool was able to match or clarify the diagnosis for 85% of childhood tumors in a prospective cohort. If further validated, this framework could be extended to derive molecular definitions for all cancer types.
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432.
小W
(2023-04-30 23:21):
#paper doi: https://doi.org/10.1038/s43018-023-00533-y inferring early genetic progression in cancers with unobtainable premalignant disease. 作者基于原发肿瘤中亚克隆之间进化关系开发了 PhylogicNDT 方法,使用原发性肿瘤样本的外显子组测序数据来推断癌症的早期遗传进展。作者进行了以下分析,(1)PhylogicNDT 方法能够重现 HPV- HNSCC 的已知遗传进展(Califano 等人的HNSCC经验进展模型) ;(2)PhylogicNDT 方法能够揭示难以获得癌前组织的 HPV+ HNSCC 的癌前遗传进展;(3)比较了 PhylogicNDT 方法 HPV+ 和 HPV– 遗传进展差异;(4)不同驱动事件的进展时间。最后,作者讨论了他们的方法在癌症早期检测、干预和预后评估方面的潜在应用,并指出了一些局限性和未来的改进方向,如考虑肿瘤内空间异质性、增加更多类型的突变、改进突变特征等。
关于HPV+ HNSCC 的 一个观点:根据PhylogicNDT 方法结果提出
,驱动事件可能发生在诊断之前 25-35 年或更早, HPV 整合位点出现在肿瘤发展的早期,并在整个肿瘤发展过程中发生额外的整合,HPV 整合是 HPV+ 癌症发生的主要贡献者。
Abstract:
Analysis of premalignant tissue has identified the typical order of somatic events leading to invasive tumors in several cancer types. For other cancers, premalignant tissue is unobtainable, leaving genetic progression …
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Analysis of premalignant tissue has identified the typical order of somatic events leading to invasive tumors in several cancer types. For other cancers, premalignant tissue is unobtainable, leaving genetic progression unknown. Here, we demonstrate how to infer progression from exome sequencing of primary tumors. Our computational method, PhylogicNDT, recapitulated the previous experimentally determined genetic progression of human papillomavirus-negative (HPV) head and neck squamous cell carcinoma (HNSCC). We then evaluated HPV HNSCC, which lacks premalignant tissue, and uncovered its previously unknown progression, identifying early drivers. We converted relative timing estimates of driver mutations and HPV integration to years before diagnosis based on a clock-like mutational signature. We associated the timing of transitions to aneuploidy with increased intratumor genetic heterogeneity and shorter overall survival. Our approach can establish previously unknown early genetic progression of cancers with unobtainable premalignant tissue, supporting development of experimental models and methods for early detection, interception and prognostication.
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433.
muton
(2023-04-30 23:19):
#paper Amygdala and cortical gamma-band responses to emotional faces depend on the attended to valence https://arxiv.org/pdf/2304.05700.pdf 杏仁核被认为贡献于情绪面孔视觉加工中自下而上的注意偏好,然而其对于情绪的反应如何与自上而下的注意相互作用却并不清楚。并且,杏仁核对情绪和注意的反应与头皮脑电相比有多大程度相似也仍有待探究。因此作者分别记录了杏仁核脑区的颅内电极以及头皮脑电伽马段的脑电活动来探究面孔加工过程中情绪和注意的交互。结果发现,在情绪检测实验中杏仁核的高频伽马出现在以中性面孔作为识别目标时,当以负性面孔作为识别目标时,低频伽马在负性面孔出现时会显著增加,并且不仅局限于杏仁核,同时在后部脑区头皮脑电记录中也存在,且时间窗早于杏仁核。这一结果符合情绪加工的多通路模型,并且是从注意(自上而下)的角度发现了伽马波在加工情绪面孔中的作用。
arXiv,
2023.
DOI: 10.48550/arXiv.2304.05700
Abstract:
The amygdala is assumed to contribute to a bottom-up attentional bias during visual processing of emotional faces. Still, how its response to emotion interacts with top-down attention is not fully …
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The amygdala is assumed to contribute to a bottom-up attentional bias during visual processing of emotional faces. Still, how its response to emotion interacts with top-down attention is not fully understood. It is also unclear if amygdala activity and scalp EEG respond to emotion and attention in a similar way. Therefore, we studied the interaction of emotion and attention during face processing in oscillatory gamma-band activity (GBA) in the amygdala and on the scalp. Amygdala signals were recorded via intracranial EEG (iEEG) in 9 patients with epilepsy. Scalp recordings were collected from 19 healthy participants. Three randomized blocks of angry, neutral, and happy faces were presented, and either negative, neutral, or positive expressions were denoted as targets. Both groups detected happy faces fastest and most accurately. In the amygdala, the earliest effect was observed around 170 ms in high GBA (105-117.5 Hz) when neutral faces served as targets. Here, GBA was higher for emotional than neutral faces. During attention to negative faces, low GBA (< 90 Hz) increased specifically for angry faces both in the amygdala and over posterior scalp regions, albeit earlier on the scalp (60 ms) than in the amygdala (210 ms). From 570 ms, amygdala high GBA (117.5-145 Hz) was also increased for both angry and neutral, compared to happy, faces. When positive faces were the targets, GBA did not differentiate between expressions. The present data reveal that attention-independent emotion detection in amygdala high GBA may only occur during a neutral focus of attention. Top-down threat vigilance coordinates widespread low GBA, biasing stimulus processing in favor of negative faces. These results are in line with a multi-pathway model of emotion processing and help specify the role of GBA in this process by revealing how attentional focus can tune timing and amplitude of emotional GBA responses.
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434.
小擎子
(2023-04-30 23:14):
#paper doi: 10.1038/s41592-021-01141-3 Nat Methods, 2021, Challenges in Benchmarking Metagenomic Profilers. 文献提出了一个研究宏基因组中会遇到的问题,即计算相对丰度时,不同生信工具给出的统计结果不同。区别就是有的结果是给出的序列丰度(DNA to DNA),有的结果给出的是物种丰度(DNA to Marker)。序列丰度和物种丰度的差别在于,有没有将物种的基因组大小考虑在其中。序列丰度是不考虑物种基因组大小的(如Kraken)。文章认为,基于物种丰度(即考虑物种基因组大小)的结果更具有解释性,建议严谨解释宏基因组分析结果,特别是从序列丰度得出的结果。
Abstract:
Accurate microbial identification and abundance estimation are crucial for metagenomics analysis. Various methods for classification of metagenomic data and estimation of taxonomic profiles, broadly referred to as metagenomic profilers, have …
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Accurate microbial identification and abundance estimation are crucial for metagenomics analysis. Various methods for classification of metagenomic data and estimation of taxonomic profiles, broadly referred to as metagenomic profilers, have been developed. Nevertheless, benchmarking of metagenomic profilers remains challenging because some tools are designed to report relative sequence abundance while others report relative taxonomic abundance. Here we show how misleading conclusions can be drawn by neglecting this distinction between relative abundance types when benchmarking metagenomic profilers. Moreover, we show compelling evidence that interchanging sequence abundance and taxonomic abundance will influence both per-sample summary statistics and cross-sample comparisons. We suggest that the microbiome research community pay attention to potentially misleading biological conclusions arising from this issue when benchmarking metagenomic profilers, by carefully considering the type of abundance data that were analyzed and interpreted and clearly stating the strategy used for metagenomic profiling.
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435.
周周复始
(2023-04-30 23:12):
#paper doi:
https://doi.org/10.48550/arXiv.2112.05149.DiffuseMorph: Unsupervised Deformable Image Registration Using Diffusion Model.可形变图像配准是医学成像中的基本任务之一。经典的配准算法通常需要较高的计算代价来进行迭代优化。虽然基于深度学习的方法进行快速图像配准已经发展起来,但要获得从移动图像到固定图像较少拓扑折叠的真实连续形变问题仍然具有挑战性。为了解决这个问题,本文提出了一种新的基于扩散模型的图像配准方法,称为DiffuseMorph。DiffuseMorph不仅通过逆扩散过程生成合成的变形图像,并且通过形变场进行图像配准。具体来说,形变场由移动图像和固定图像之间形变的条件分数函数生成。所以可以通过简单地缩放分数的潜在特征,对连续形变进行配准。2D面部和3D医学图像配准任务的实验结果表明,本文方法提供了灵活的形变和拓扑保持能力。
arXiv,
2021.
DOI: 10.48550/arXiv.2112.05149
Abstract:
Deformable image registration is one of the fundamental tasks in medical imaging. Classical registration algorithms usually require a high computational cost for iterative optimizations. Although deep-learning-based methods have been developed …
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Deformable image registration is one of the fundamental tasks in medical imaging. Classical registration algorithms usually require a high computational cost for iterative optimizations. Although deep-learning-based methods have been developed for fast image registration, it is still challenging to obtain realistic continuous deformations from a moving image to a fixed image with less topological folding problem. To address this, here we present a novel diffusion-model-based image registration method, called DiffuseMorph. DiffuseMorph not only generates synthetic deformed images through reverse diffusion but also allows image registration by deformation fields. Specifically, the deformation fields are generated by the conditional score function of the deformation between the moving and fixed images, so that the registration can be performed from continuous deformation by simply scaling the latent feature of the score. Experimental results on 2D facial and 3D medical image registration tasks demonstrate that our method provides flexible deformations with topology preservation capability.
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436.
cellsarts
(2023-04-30 23:11):
#paper SignalP 6.0使用蛋白质语言模型预测所有五种类型的信号肽https://doi.org/10.1038/s41587-021-01156-3 信号肽(SPs)是控制所有生物体中蛋白质分泌和转运的短氨基酸序列。SPs可以从序列数据中预测,但现有算法无法检测到所有已知类型的SPs。我们介绍了SignalP 6.0,这是一个机器学习模型,可以检测所有五种SP类型,并适用于宏基因组数据。SPs是一种短的n端氨基酸序列,在真核生物中将蛋白定向到分泌(Sec)途径,并在原核生物中跨血浆(内)膜进行转运。由于SPs的综合实验鉴定是不现实的,因此SPs的计算预测与细胞生物学的研究具有很高的相关性。SP预测工具能够识别遵循一般分泌或双精氨酸易位(Tat)途径的蛋白质,并预测信号肽酶(SPase)在序列中切割sp2,3的位置。SignalP 5.0能够预测SPase I (Sec/SPI)或SPase II (Sec/ SPII,原核脂蛋白)切割的Sec底物和SPase I (Tat/SPI)切割的Tat底物4。然而,由于缺乏注释数据,SignalP 5.0无法检测由SPase II切割的Tat底物或由SPase III (prepilin peptide ase,有时称为SPase IV2)加工的Sec底物。此类Sec/SPIII SPs控制IV型匹林样蛋白的易位,而IV型匹林样蛋白在原核生物的粘附、运动和DNA摄取中起关键作用。此外,SignalP 5.0对SP结构是不可知的,因为它不能定义构成SP生物学功能的子区(n端n区、疏水h区和c端c区)。
在这里,我们提出了基于蛋白质语言模型(LMs) 6-9的SignalP 6.0,该模型使用了来自生命所有领域数百万未注释的蛋白质序列的信息。LMs创建捕获其生物特性和结构的蛋白质的语义表示。使用这些蛋白质表示,SignalP 6.0可以预测以前版本无法检测到的其他类型的SPs,同时更好地推断与用于创建模型的蛋白质和来源未知的宏基因组数据有远亲性的蛋白质。此外,它还能够确定SPs的分区域.
Abstract:
Signal peptides (SPs) are short amino acid sequences that control protein secretion and translocation in all living organisms. SPs can be predicted from sequence data, but existing algorithms are unable …
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Signal peptides (SPs) are short amino acid sequences that control protein secretion and translocation in all living organisms. SPs can be predicted from sequence data, but existing algorithms are unable to detect all known types of SPs. We introduce SignalP 6.0, a machine learning model that detects all five SP types and is applicable to metagenomic data.
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437.
小小小小小小萌
(2023-04-30 22:02):
#paper doi: 10.1016/j.ccell.2023.03.008 Neutrophil extracellular traps formed during chemotherapy confer treatment resistance via TGF-b activation. 该研究对小鼠静脉注射乳腺癌细胞并待其转移7天,用化疗药物处理后,检测比较了肺部的细胞变化情况,结果发现对于肿瘤肺转移小鼠,化疗会导致肺部中性粒细胞增多。当用Ly6G抗体清除掉中性粒细胞之后,化疗效果又得到了显著增强。血液中的中性粒细胞通过形成NET以杀害微生物,该研究还表明了抑制NET可以增强化疗效果。最后解释了化疗促进NET 形成的生物学机制。
Abstract:
Metastasis is the major cause of cancer death, and the development of therapy resistance is common. The tumor microenvironment can confer chemotherapy resistance (chemoresistance), but little is known about how …
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Metastasis is the major cause of cancer death, and the development of therapy resistance is common. The tumor microenvironment can confer chemotherapy resistance (chemoresistance), but little is known about how specific host cells influence therapy outcome. We show that chemotherapy induces neutrophil recruitment and neutrophil extracellular trap (NET) formation, which reduces therapy response in mouse models of breast cancer lung metastasis. We reveal that chemotherapy-treated cancer cells secrete IL-1β, which in turn triggers NET formation. Two NET-associated proteins are required to induce chemoresistance: integrin-αvβ1, which traps latent TGF-β, and matrix metalloproteinase 9, which cleaves and activates the trapped latent TGF-β. TGF-β activation causes cancer cells to undergo epithelial-to-mesenchymal transition and correlates with chemoresistance. Our work demonstrates that NETs regulate the activities of neighboring cells by trapping and activating cytokines and suggests that chemoresistance in the metastatic setting can be reduced or prevented by targeting the IL-1β-NET-TGF-β axis.
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438.
哪有情可长
(2023-04-30 21:56):
#paper reducing brassinosteroid signalling enhances grain yield in semi-dwarf wheat doi: doi.org/10.1038/s41586-023-06023-6. 通过多年的大规模田间表型调查和遗传学研究,鉴定到一个能够提升小麦群体产量的关键位点,其中该位点跟已知的Rht基因处于相同的区段,通过构建小麦该区段内三个基因的突变体,发现该基因跟绿色革命基因相比,能够保持半矮杆株型,且茎秆强度、植株耐密性、收获指数、千粒重和产量均有显著的提升。该基因可以是近现代小麦品种后期育种增产的目标基因,对于小麦产量提升具有重要的作用。同时该研究历时10年,通过正向遗传鉴定基因后,对于小麦中的明星基因如何处理也是一个很好的典范,同时也给我分析小麦数据提供了思路,GWAS结果中一些定位到明星基因的位点还可以看下SVN等情况。
Abstract:
Modern green revolution varieties of wheat (Triticum aestivum L.) confer semi-dwarf and lodging-resistant plant architecture owing to the Reduced height-B1b (Rht-B1b) and Rht-D1b alleles. However, both Rht-B1b and Rht-D1b are …
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Modern green revolution varieties of wheat (Triticum aestivum L.) confer semi-dwarf and lodging-resistant plant architecture owing to the Reduced height-B1b (Rht-B1b) and Rht-D1b alleles. However, both Rht-B1b and Rht-D1b are gain-of-function mutant alleles encoding gibberellin signalling repressors that stably repress plant growth and negatively affect nitrogen-use efficiency and grain filling. Therefore, the green revolution varieties of wheat harbouring Rht-B1b or Rht-D1b usually produce smaller grain and require higher nitrogen fertilizer inputs to maintain their grain yields. Here we describe a strategy to design semi-dwarf wheat varieties without the need for Rht-B1b or Rht-D1b alleles. We discovered that absence of Rht-B1 and ZnF-B (encoding a RING-type E3 ligase) through a natural deletion of a haploblock of about 500 kilobases shaped semi-dwarf plants with more compact plant architecture and substantially improved grain yield (up to 15.2%) in field trials. Further genetic analysis confirmed that the deletion of ZnF-B induced the semi-dwarf trait in the absence of the Rht-B1b and Rht-D1b alleles through attenuating brassinosteroid (BR) perception. ZnF acts as a BR signalling activator to facilitate proteasomal destruction of the BR signalling repressor BRI1 kinase inhibitor 1 (TaBKI1), and loss of ZnF stabilizes TaBKI1 to block BR signalling transduction. Our findings not only identified a pivotal BR signalling modulator but also provided a creative strategy to design high-yield semi-dwarf wheat varieties by manipulating the BR signal pathway to sustain wheat production.
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439.
张贝
(2023-04-30 21:54):
#paper Detecting Liver Cancer Using Cell-Free DNA Fragmentomes
Cancer Discov. 023 Mar 1;13(3):616-631. doi: 10.1158/2159-8290.CD-22-0659. 本文是DELFI技术应用于肝癌筛查的最新研究成果。DELFI的全称是DNA evaluation of fragments for early interception,即利用血液cfDNA全基因组片段化特征间的差异,来区分肿瘤患者和非癌症受试者。本文构建了两个机器学习模型,分别适用于肝癌高危人群和低风险人群,这两个模型纳入的特征类型略有差异,在低风险人群模型中新增TFBS特征。最后,作者使用蒙特卡洛模拟评估DELFI模型在10万理论高危人群中的性能,与指南推荐的腹部超声联合AFP的检测方法相比,DELFI技术不仅极大提高肝癌的检出率,同时有望降低肝癌检测的假阴性率。
Abstract:
Abstract Liver cancer is a major cause of cancer mortality worldwide. Screening individuals at high-risk, including those with cirrhosis and viral hepatitis, provides an avenue for improved survival, but current …
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Abstract Liver cancer is a major cause of cancer mortality worldwide. Screening individuals at high-risk, including those with cirrhosis and viral hepatitis, provides an avenue for improved survival, but current screening methods are inadequate. In this study, we used whole-genome cell-free DNA fragmentome analyses to evaluate 724 individuals from the US, EU, or Hong Kong with hepatocellular carcinoma (HCC) or who were at average or high-risk for HCC. Using a machine learning model that incorporated multi-feature fragmentome data, the sensitivity for detecting cancer was 88% in an average risk population at 98% specificity, and 85% among high-risk individuals at 80% specificity. We validated these results in an independent population. cfDNA fragmentation changes reflected genomic and chromatin changes in liver cancer, including from transcription factor binding sites. These findings provide a biological basis for changes in cfDNA fragmentation in patients with liver cancer and provide an accessible approach for non-invasive cancer detection.
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440.
大勇
(2023-04-30 21:33):
#paper Tim-4+ cavity-resident macrophages impair anti-tumor CD8+ T cell immunity. Cancer Cell. 2021 Jul 12;39(7):973-988.e9. doi: 10.1016/j.ccell.2021.05.006. Epub 2021 Jun 10. PMID: 34115989; PMCID: PMC9115604.文章的概念比较新颖,探究了腹腔转移肿瘤对免疫检查点抑制剂耐药的相关机制,找到了体腔驻留的TIM4阳性的巨噬细胞在其中发挥的影响,利用TIM4阳性的巨噬细胞与CD8+CD39+T细胞的相互作用,阐释了体腔驻留巨噬细胞可以抑制CD8T细胞的功能,并且TIM4单抗可以与PD1单抗联合用药治疗肿瘤,提高疗效。
Abstract:
Immune checkpoint blockade (ICB) has been a remarkable clinical advance for cancer; however, the majority of patients do not respond to ICB therapy. We show that metastatic disease in the …
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Immune checkpoint blockade (ICB) has been a remarkable clinical advance for cancer; however, the majority of patients do not respond to ICB therapy. We show that metastatic disease in the pleural and peritoneal cavities is associated with poor clinical outcomes after ICB therapy. Cavity-resident macrophages express high levels of Tim-4, a receptor for phosphatidylserine (PS), and this is associated with reduced numbers of CD8 T cells with tumor-reactive features in pleural effusions and peritoneal ascites from patients with cancer. We mechanistically demonstrate that viable and cytotoxic anti-tumor CD8 T cells upregulate PS and this renders them susceptible to sequestration away from tumor targets and proliferation suppression by Tim-4 macrophages. Tim-4 blockade abrogates this sequestration and proliferation suppression and enhances anti-tumor efficacy in models of anti-PD-1 therapy and adoptive T cell therapy in mice. Thus, Tim-4 cavity-resident macrophages limit the efficacy of immunotherapies in these microenvironments.
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