Learning Spiking Neural Network from Easy to Hard task

Starting with small and simple concepts, and gradually introducing complex and difficult concepts is the natural process of human learning. Spiking Neural Networks (SNNs) aim to mimic the way humans process information, but current SNNs models treat all samples equally, which does not align with the principles of human learning and overlooks the biological plausibility of SNNs. To address this, we propose a CL-SNN model that introduces Curriculum Learning(CL) into SNNs, making SNNs learn more like humans and providing higher biological interpretability. CL is a training strategy that advocates presenting easier data to models before gradually introducing more challenging data, mimicking the human learning process. We use a confidence-aware loss to measure and process the samples with different difficulty levels. By learning the confidence of different samples, the model reduces the contribution of difficult samples to parameter optimization automatically. We conducted experiments on static image datasets MNIST, Fashion-MNIST, CIFAR10, and neuromorphic datasets N-MNIST, CIFAR10-DVS, DVS-Gesture. The results are promising. To our best knowledge, this is the first proposal to enhance the biologically plausibility of SNNs by introducing CL

Oropharyngeal Muscle Exercise Therapy Improves Signs and Symptoms of Post-stroke Moderate Obstructive Sleep Apnea Syndrome

The primary aim of the current study was to assess the effects of oropharingeal muscle exercises in obstruction severity on stroke patients with OSAS. The secondary aims were to evaluate the effects of the exercises on rehabilitation of neurological function, sleeping, and morphology change of upper airway. An open-label, single-blind, parallel-group, randomized, controlled trial was designed. Fifty post-stroke patients with moderate OSAS were randomly assigned into 2 groups (25 in each group). For the therapy group, oropharyngeal muscle exercise was performed during the daytime for 20 min, twice a day, for 6 weeks. The control group was subjected to sham therapy of deep breathing. Primary outcomes were the obstruction severity by polysomnography. Secondary outcomes included recovery of motor and neurocognitive function, personal activities of daily living assessment (ADL), sleep quality and sleepiness scale. It also included upper airway magnetic resonance imaging (MRI) measurements. Assessments were made at baseline and after 6-week exercise. Finally, 49 patients completed the study. The apnea–hypopnea index, snore index, arousal index, and minimum oxygen saturation improved after exercise (P < 0.05). Oropharyngeal muscle exercises improved subjective measurements of sleep quality (P = 0.017), daily sleepiness (P = 0.005), and performance (both P < 0.05) except for neurocognition (P = 0.741). The changes in obstruction improvement, sleep characteristics and performance scale were also associated with training time, as detected by Pearson's correlation analysis. The anatomic structural remodeling of the pharyngeal airway was measured using MRI, including the lager retropalatal distance (P = 0.018) and shorter length of soft palate (P = 0.044) compared with the baseline. Hence, oropharyngeal muscle exercise is a promising alternative treatment strategy for stroke patients with moderate OSAS.Clinical Trial Registration:http://www.chictr.org.cn. Unique identifier: ChiCTR-IPR-1600997

The Chinese pine genome and methylome unveil key features of conifer evolution

Conifers dominate the world's forest ecosystems and are the most widely planted tree species. Their giant and complex genomes present great challenges for assembling a complete reference genome for evolutionary and genomic studies. We present a 25.4-Gb chromosome-level assembly of Chinese pine (Pinus tabuliformis) and revealed that its genome size is mostly attributable to huge intergenic regions and long introns with high transposable element (TE) content. Large genes with long introns exhibited higher expressions levels. Despite a lack of recent whole-genome duplication, 91.2% of genes were duplicated through dispersed duplication, and expanded gene families are mainly related to stress responses, which may underpin conifers' adaptation, particularly in cold and/or arid conditions. The reproductive regulation network is distinct compared with angiosperms. Slow removal of TEs with high-level methylation may have contributed to genomic expansion. This study provides insights into conifer evolution and resources for advancing research on conifer adaptation and development

The evaluation of plantar pressure distribution in type II diabetic patients and non-diabetic adults in China

Plantar pressures in TypeIIdiabetic patients and control adults during normal walking were compared in this study. A total of 70 (45♀+25♂) type 2 diabetic patients without neuropathy (aged 63.6±7.6 years; BMI 24.3±2.9; duration of diabetes 12.3±6.9 years) and 70 (45♀+25♂) non-diabetic adults (aged 62.5±8.6 years; BMI 22.4±2.5) in China were recruited. Plantar pressures were collected by EMED system (Novel, Germany). All participants were required to walk barefoot at a self-selected speed, the parameters of peak pressure and contact areas were collected. During analysis ten plantar regions were identified: hind foot, midfoot, the first (MH1), second (MH2), third (MH3), fourth (MH4), fifth (MH5) metatarsals, big toe, second toe and toes 345. Only data from the right foot was analyzed, independent samples t-tests were used to compare dynamic variables between two groups. Results: No significant differences of peak pressures were found between male and female. Except for midfoot, second toe and toe 345 regions, no significant differences of peak pressures were found in other seven regions between two groups. Pearson correlations were performed between BMI and peak pressures for the foot across both groups. No correlation was found between BMI and peak pressure

In-Hospital Peak Glycemia in Predicting No-Reflow Phenomenon in Diabetic Patients with STEMI Treated with Primary Percutaneous Coronary Intervention

Although percutaneous coronary intervention (PCI) significantly improves the prognosis for myocardial infarction, the no-reflow phenomenon is still the major adverse complication of PCI leading to increased mortality, especially for the patients with ST-segment elevation myocardial infarction (STEMI) combined with diabetes. To reduce the occurrence of no-reflow, prognostic factors must be identified for no-reflow phenomenon before PCI. A total of 262 participants with acute STEMI and diabetes were recruited into our cardiovascular center and underwent primary PCI for the analyses of prognostic factors of no-reflow. The patients were divided into two groups according to thrombolysis in myocardial infarction (TIMI): the normal flow and no-reflow groups, and related factors were analyzed with different statistical methods. In the present investigation, the in-hospital peak glycemia was significantly higher in the no-reflow group than the normal flow group, while more narrowed vessels, higher level of initial TIMI flow, were observed in the patients of the no-reflow group. A multivariate logistic regression analysis further demonstrated that peak glycemia was an independent predictor for no-reflow in the diabetic patients with STEMI. Our data indicated the importance of the proper control of glucose before PCI for the diabetic patients with STEMI before PCI to reduce the occurrence of the no-reflow after operation

Application of CRISPR/Cas9 in plant biology

The CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins) system was first identified in bacteria and archaea and can degrade exogenous substrates. It was developed as a gene editing technology in 2013. Over the subsequent years, it has received extensive attention owing to its easy manipulation, high efficiency, and wide application in gene mutation and transcriptional regulation in mammals and plants. The process of CRISPR/Cas is optimized constantly and its application has also expanded dramatically. Therefore, CRISPR/Cas is considered a revolutionary technology in plant biology. Here, we introduce the mechanism of the type II CRISPR/Cas called CRISPR/Cas9, update its recent advances in various applications in plants, and discuss its future prospects to provide an argument for its use in the study of medicinal plants

Human umbilical cord mesenchymal stem cells promote carcinoma growth and lymph node metastasis when co-injected with esophageal carcinoma cells in nude mice

BACKGROUND: Human umbilical cord blood derived-mesenchymal stem cells (hUCMSCs) offer an attractive alternative to bone marrow-derived MSCs (BMMSCs) for cell-based therapy as it is a less invasive source of biological material. However, limited studies have been conducted with hUCMSCs as compared to BMMSCs. The present study was conducted to evaluate the effects of hUCMSCs in esophageal carcinoma (EC). METHODS: hUCMSCs together with EC cells were transplanted subcutaneously into BALB/c nude mice to observe the effects of hUCMSCs on tumor establishment. hUCMSCs injected through the caudal vein to the mice with pre-established EC to observe the effects of hUCMSCs on tumor outgrowth. In order to elucidate the underlying mechanisms, we also performed in vitro experiments including directly co-culture, transwell assay, proliferation assay and western blotting analysis. RESULTS: hUCMSCs promoted EC formation in nude mice. In the in vivo model of pre-established EC, intravenously injected hUCMSCs potently promoted tumor growth. When in vitro co-cultured with hUCMSCs, EC cells proliferation increased. After co-cultured with hUCMSCs through transwell system, EC cells showed increased proliferation. Through transwell assay, we also observed that EC cells recruited MSCs, and MSCs promoted EC cells migration and invasion. Western blotting data showed that the expressions of proliferation related proteins Bcl-2, survivin and metastasis related proteins MMP-2 and MMP-9 were up-regulated in the EC cells transwell co-cultured with hUCMSCs. CONCLUSIONS: Our results indicated that hUCMSCs could favor tumor growth in vivo and in vitro. Thus, the exploitation of hUCMSCs in new therapeutic strategies should be cautious under the malignant conditions

Four Cu(II)/Co(II) coordination polymers based on N,N′-di(3-pyridyl)sebacicdiamide: influence of different carboxylate ancillary ligands on structures and properties

<p>Four Cu(II)/Co(II) coordination polymers, [Cu(L)(BDC)(H₂O)]·3H₂O (<b>1</b>), [Cu(L)(DNBA)₂] (<b>2</b>), [Co(L)₂(DNBA)₂] (<b>3</b>), and [Co(L)(NIPH)(H₂O)]·H₂O (<b>4</b>) (H₂BDC = 1,4-benzenedicarboxylic acid, HDNBA = 3,5-dinitrobenzoic acid, H₂NIPH = 5-nitroisophthalic acid, L = N,N′-di(3-pyridyl)sebacicdiamide), have been synthesized under hydrothermal conditions. The structures of <b>1</b>–<b>4</b> have been determined by single-crystal X-ray diffraction analyses and <b>1</b>–<b>4</b> were further characterized by infrared spectroscopy and thermogravimetric analyses. Complex <b>1</b> is a 2-D polymeric layer with a 4-connected <i>sql</i> topology. Complex <b>2</b> displays a 1-D zigzag chain. Complex <b>3</b> possesses a 1-D double-chain structure. Complex <b>4</b> exhibits a ribbon chain based on the 1-D [Co–L]_n<i>meso</i>-helical chain. Adjacent layers for <b>1</b> and adjacent chains for <b>2</b>–<b>4</b> are further linked by hydrogen bonding or <i>π</i>–<i>π</i> stacking interactions to form 3-D supramolecular networks. The differences of carboxylates and metal ions show significant effect on the ultimate architectures of the four complexes. Thermal stabilities, fluorescent properties and photocatalytic activities of <b>1</b>–<b>4</b> were also studied.</p