Microsurgical Techniques Used to Construct the Vascularized and Neurotized Tissue Engineered Bone

The lack of vascularization in the tissue engineered bone results in poor survival and ossification. Tissue engineered bone can be wrapped in the soft tissue flaps which are rich in blood supply to complete the vascularization in vivo by microsurgical technique, and the surface of the bone graft can be invaded with new vascular network. The intrinsic vascularization can be induced via a blood vessel or an arteriovenous loop located centrally in the bone graft by microsurgical technique. The peripheral nerve especially peptidergic nerve has effect on the bone regeneration. The peptidergic nerve can be used to construct the neurotized tissue engineered bone by implanting the nerve fiber into the center of bone graft. Thus, constructing a highly vascularized and neurotized tissue engineered bone according with the theory of biomimetics has become a useful method for repairing the large bone defect. Many researchers have used the microsurgical techniques to enhance the vascularization and neurotization of tissue engineered bone and to get a better osteogenesis effect. This review aims to summarize the microsurgical techniques mostly used to construct the vascularized and neurotized tissue engineered bone

Asymmetric response of soil methane uptake rate to land degradation and restoration: Data synthesis

Land degradation and restoration profoundly affect soil CH(4)uptake capacity in terrestrial ecosystems. However, a comprehensive assessment of the response of soil CH(4)uptake to land degradation and restoration at global scale is not available. Here, we present a global meta-analysis with a database of 228 observations from 83 studies to investigate the effects of land degradation and restoration on the capacity of soil CH(4)uptake. We found that land degradation significantly decreased the capacity of soil CH(4)uptake, except the conversion of pasture to cropland where the soil CH(4)uptake rate showed no response. In contrast, all types of land restoration significantly increased the capacity of soil CH(4)uptake. Interestingly, the response of soil CH(4)uptake rate to land degradation and restoration was asymmetric: the increased soil CH(4)uptake rate in response to the land restoration was smaller compared to the decrease in CH(4)uptake rate induced by the land degradation. The effect of land degradation on soil CH(4)uptake rate was not dependent on the time since land use change, but the CH(4)sink strength increased with the time since land restoration. The response of soil CH(4)uptake rate to both land degradation and restoration was predominantly regulated by changes in the soil water-filled pore space, soil bulk density, and pH, whereas alterations in the substrate quantity and quality had negligible effect. Additionally, the effects of land degradation and restoration on soil CH(4)uptake were strongly related to the mean annual precipitation and soil texture. Overall, our results provide novel insights for understanding of how land degradation and restoration can affect the CH(4)sink strength of upland soils, and more importantly, our findings are beneficial to take measures to enhance the potential of soil CH(4)uptake in response to global land use change

Cancer Stem Cells and Immunosuppressive Microenvironment in Glioma

Glioma is one of the most common malignant tumors of the central nervous system and is characterized by extensive infiltrative growth, neovascularization, and resistance to various combined therapies. In addition to heterogenous populations of tumor cells, the glioma stem cells (GSCs) and other nontumor cells present in the glioma microenvironment serve as critical regulators of tumor progression and recurrence. In this review, we discuss the role of several resident or peripheral factors with distinct tumor-promoting features and their dynamic interactions in the development of glioma. Localized antitumor factors could be silenced or even converted to suppressive phenotypes, due to stemness-related cell reprogramming and immunosuppressive mediators in glioma-derived microenvironment. Furthermore, we summarize the latest knowledge on GSCs and key microenvironment components, and discuss the emerging immunotherapeutic strategies to cure this disease

Traffic4cast at NeurIPS 2022 -- Predict Dynamics along Graph Edges from Sparse Node Data: Whole City Traffic and ETA from Stationary Vehicle Detectors

The global trends of urbanization and increased personal mobility force us to rethink the way we live and use urban space. The Traffic4cast competition series tackles this problem in a data-driven way, advancing the latest methods in machine learning for modeling complex spatial systems over time. In this edition, our dynamic road graph data combine information from road maps, $10^{12}$ probe data points, and stationary vehicle detectors in three cities over the span of two years. While stationary vehicle detectors are the most accurate way to capture traffic volume, they are only available in few locations. Traffic4cast 2022 explores models that have the ability to generalize loosely related temporal vertex data on just a few nodes to predict dynamic future traffic states on the edges of the entire road graph. In the core challenge, participants are invited to predict the likelihoods of three congestion classes derived from the speed levels in the GPS data for the entire road graph in three cities 15 min into the future. We only provide vehicle count data from spatially sparse stationary vehicle detectors in these three cities as model input for this task. The data are aggregated in 15 min time bins for one hour prior to the prediction time. For the extended challenge, participants are tasked to predict the average travel times on super-segments 15 min into the future - super-segments are longer sequences of road segments in the graph. The competition results provide an important advance in the prediction of complex city-wide traffic states just from publicly available sparse vehicle data and without the need for large amounts of real-time floating vehicle data.Comment: Pre-print under review, submitted to Proceedings of Machine Learning Researc

Effects of Fe self-ion irradiation on a low carbon MX-ODS steel at 550°C

Oxide Dispersion Strengthened (ODS) steels with nano-scale oxides have become one of the candidate materials used in advanced nuclear reactor systems. A novel MX-ODS steel with extremely low carbon content was irradiated with 3 MeV Fe ions at 550°C up to peak damage of 70 dpa. The steel contains uniformly distributed Y2O3 nano-precipitates with an average size of 3.5 nm and a number density of 5 × 1022/m3. A V-rich shell was found surrounding the core of Y, O, and Si at some particles. Two types of large precipitates, Y-Ta-Si oxides, and VN, were observed in the steel instead of carbides. Voids of very small size are present due to irradiation and the calculated void swelling was only 0.004%, suggesting good irradiation tolerance of the MX-ODS steel in this study. Fine and dense oxide nano-precipitates and their shell-core structure remained stable while the shape of large precipitates changed after irradiation

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts