Hadwiger’s conjecture for powers of cycles and their complements

AbstractC. Thomassen showed that powers of certain cycles are counterexamples to Hajós’ conjecture. We prove that powers of cycles and their complements satisfy Hadwiger’s conjecture, that is, every k-chromatic graph has a k-clique as a minor

Verilog-to-PyG -- A Framework for Graph Learning and Augmentation on RTL Designs

The complexity of modern hardware designs necessitates advanced methodologies for optimizing and analyzing modern digital systems. In recent times, machine learning (ML) methodologies have emerged as potent instruments for assessing design quality-of-results at the Register-Transfer Level (RTL) or Boolean level, aiming to expedite design exploration of advanced RTL configurations. In this presentation, we introduce an innovative open-source framework that translates RTL designs into graph representation foundations, which can be seamlessly integrated with the PyTorch Geometric graph learning platform. Furthermore, the Verilog-to-PyG (V2PYG) framework is compatible with the open-source Electronic Design Automation (EDA) toolchain OpenROAD, facilitating the collection of labeled datasets in an utterly open-source manner. Additionally, we will present novel RTL data augmentation methods (incorporated in our framework) that enable functional equivalent design augmentation for the construction of an extensive graph-based RTL design database. Lastly, we will showcase several using cases of V2PYG with detailed scripting examples. V2PYG can be found at \url{https://yu-maryland.github.io/Verilog-to-PyG/}.Comment: 8 pages, International Conference on Computer-Aided Design (ICCAD'23

The vagus nerve regulates immunometabolic homeostasis in the ovine fetus near term: impact on terminal ileum

The contribution of the vagus nerve to inflammation and glucosensing in the fetus is not understood. We hypothesized that vagotomy (Vx) will result in hyperglycemia and this will be enhanced during systemic and organ-specific inflammation. Efferent vagus nerve stimulation (VNS) should reverse this phenotype. Near-term fetal sheep (n=57) were surgically prepared with vascular catheters and ECG electrodes as control and treatment groups (lipopolysaccharide (LPS), Vx+LPS, Vx+LPS+selective efferent VNS). Fetal arterial blood samples were drawn for 7 days to profile inflammation (IL-6), insulin, blood gas and metabolism (glucose). At 54 h, a necropsy was performed; terminal ileum macrophages; CD11c (M1 phenotype) immunofluorescence was quantified to detect inflammation. Across the treatment groups, blood gas and cardiovascular changes indicated mild septicemia. At 3 h, in the LPS group IL-6 peaked; that peak was decreased in Vx+LPS400 and doubled in Vx+LPS800 group; the efferent VNS sped up the reduction of the inflammatory response profile over 54 h. M1 macrophage activity was increased in the LPS and Vx+LPS800 groups only. Glucose and insulin levels in the Vx+LPS group were respectively 1.3-fold and 2.3-fold higher vs. control at 3 h, and the efferent VNS normalized glucose levels. Complete withdrawal of vagal innervation results in a 72h delayed onset of sustained hyperglycemia for at least 54h and intermittent hyperinsulinemia. Under conditions of moderate fetal inflammation, this is related to higher levels of gut inflammation; the efferent VNS reduces the systemic inflammatory response as well as restores both the levels of glucose and terminal ileum inflammation, but not the insulin levels. Our findings reveal a novel regulatory, hormetic, role of the vagus nerve in the immunometabolic response to endotoxin in near-term fetuses

α7 Nicotinic Acetylcholine Receptor Signaling Modulates Ovine Fetal Brain Astrocytes Transcriptome in Response to Endotoxin

Neuroinflammation in utero may result in lifelong neurological disabilities. Astrocytes play a pivotal role in this process, but the mechanisms are poorly understood. No early postnatal treatment strategies exist to enhance neuroprotective potential of astrocytes. We hypothesized that agonism on α7 nicotinic acetylcholine receptor (α7nAChR) in fetal astrocytes will augment their neuroprotective transcriptome profile, while the inhibition of α7nAChR will achieve the opposite. Using an in vivo–in vitro model of developmental programming of neuroinflammation induced by lipopolysaccharide (LPS), we validated this hypothesis in primary fetal sheep astrocytes cultures re-exposed to LPS in the presence of a selective α7nAChR agonist or antagonist. Our RNAseq findings show that a pro-inflammatory astrocyte transcriptome phenotype acquired in vitro by LPS stimulation is reversed with α7nAChR agonistic stimulation. Conversely, α7nAChR inhibition potentiates the pro-inflammatory astrocytic transcriptome phenotype. Furthermore, we conducted a secondary transcriptome analysis against the identical α7nAChR experiments in fetal sheep primary microglia cultures. Similar to findings in fetal microglia, in fetal astrocytes we observed a memory effect of in vivo exposure to inflammation, expressed in a perturbation of the iron homeostasis signaling pathway (hemoxygenase 1, HMOX1), which persisted under pre-treatment with α7nAChR antagonist but was reversed with α7nAChR agonist. For both glia cell types, common pathways activated due to LPS included neuroinflammation signaling and NF-κB signaling in some, but not all comparisons. However, overall, the overlap on the level of signaling pathways was rather minimal. Astrocytes, not microglia—the primary immune cells of the brain, were characterized by unique inhibition patterns of STAT3 pathway due to agonistic stimulation of α7nAChR prior to LPS exposure. Lastly, we discuss the implications of our findings for fetal and postnatal brain development

Evaluation of Outburst Potential at Sihe Coal Mine, China

The coal and gas outburst accident on May 20, 2007 at Sihe Coal Mine is unique in that there is no or very little soft coal in the coal seam and that the coefficient of coal strength is very high. It was also indicated in the outburst that there is a very high gas content of 20-30 m3/t in the coal seam nearby the outburst site. Based on field test and observations, together with laboratory experiments, detailed analysis was conducted on controlling factors of coal and gas outburst potential at Sihe Coal Mine. Stress data available from Sihe Coal Mine, northern China and other parts of world, were also taken into account to facilitate the analysis. The results show that the stress level is not abnormal compared to other coal fields in China prone to outbursts, and that the gas contained in the coal seam is the main factor that triggered the outburst. The results show that outbursts are limited to only a small part of the whole coal seam and that the East part of coal field is not prone to outbursts

Study on Comprehensive Technology of Coal and Gas Outburst Prevention in Mining Panels

AbstractWith the goal to solve problems of coal and gas outbursts prevention in a mining panel, the method developed by the authors of this paper was employed to define the critical value of gas content based data form a panel of Mine A of a coal mining group in Shanxi Province. Outburst management in the panel was successfully implemented based on the defined critical value of gas content and gas geological maps. The principle of drainage borehole layout was studied in details. A mathematical model was established to determine reasonable drainage time, and a method was developed to evaluate the effects of measures on outbursts presentation. The research results show that coals with different rank have very different absorption capacity, and that the critical value of gas content is different and closely relevant to coal rank. Areas of outburst risk are clearly identified by gas-geological data shown on the gas-geology map, and the evaluation method was applied to make sure that the panel was free of outburst risk after gas drainage. The integration of all the research results eliminated outburst risk in the panel