Introduction␥␦ T cells are key players in the immune surveillance of cellular distress, thanks to their ability to recognize conserved determinants up-regulated after inflammation, infection, or cell transformation. 1,2 Although ␥␦ T-cell receptors (TCRs) contribute to detection of danger-associated determinants, ligands for these receptors have been identified in a few cases only. 3 Thus, the antigenic specificity of ␥␦ T cells and their fine activation modalities in response to cell stress remain largely unknown.One of the best studied ␥␦ T-cell subsets in humans expresses V␥9V␦2 TCR and predominates in blood, composing several percent of the whole peripheral lymphoid pool in most adults. V␥9V␦2 T cells are activated by nonpeptidic phosphorylated isoprenoid pathway metabolites, 4-6 hereafter referred to as phosphoagonists (PAg). Natural V␥9V␦2-stimulating PAg include isopentenyl pyrophosphate (IPP), 7 a metabolite of the mevalonate pathway found in mammalian cells and the desoxyxylulose phosphate pathway shared by many microorganisms, and hydroxy-methyl-butyl-pyrophosphate, 8 an intermediate of the latter pathway. PAg detection by ␥␦ T cells underlies their broad reactivity toward infected and transformed cells. Indeed, tumor cell recognition by V␥9V␦2 T cells is linked to enhanced production of the weak agonist IPP, resulting from increased cell metabolism and cholesterol biosynthesis. Accordingly, pharmacologic inhibitors of the mevalonate pathway that up-regulate (eg, aminobisphosphonates, NBP) or down-regulate (eg, statins) IPP production, respectively, increase or decrease antitumor V␥9V␦2 T-cell responses. 9,10 Moreover, because of the high V␥9V␦2 T cell-stimulating activity of the microbial agonist hydroxy-methyl-butyl-pyrophosphate, V␥9V␦2 T-cell responses are elicited by infected cells producing even traces of this PAg. 8 Although PAg-induced activation is restricted to V␥9V␦2 T cells and can be conferred by V␥9V␦2 TCR gene transfer, 11,12 attempts to detect cognate interactions between PAg and V␥9V␦2 TCR have failed so far. 13 So how V␥9V␦2 T cells sense PAg remains an enigma. PAg rapidly induce Ca 2ϩ signaling and activation of V␥9V␦2 T-cell clones, but this requires cell-to-cell contact, suggesting the implication of additional target cell surface receptors in this phenomenon. 11,14 PAg elicit V␥9V␦2 T-cell responses against basically all human cells, irrespective of their tissue origin, but do not induce recognition of any murine target cells. Therefore, the putative target cell receptors involved in PAg-mediated T-cell activation are expected to be broadly expressed by human, but not murine, cells.Activation of antigen-stimulated T cells is tuned by interactions involving T cell-derived CD28-related receptors and target cellderived B7-related counter-receptors, 15 which family includes members, such as Skint and butyrophilin (BTN) receptors. The mandatory role played by Skint-1 in the intrathymic positive There is an Inside Blood commentary on this article in this issue.The online version of this...

High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal elements. Although in the infant stage, the emerging of this new family of materials has brought new opportunities for material design and property tailoring. Distinct from metals, the diversity in crystal structure and electronic structure of ceramics provides huge space for properties tuning through band structure engineering and phonon engineering. Aside from strengthening, hardening, and low thermal conductivity that have already been found in high-entropy alloys, new properties like colossal dielectric constant, super ionic conductivity, severe anisotropic thermal expansion coefficient, strong electromagnetic wave absorption, etc., have been discovered in HECs. As a response to the rapid development in this nascent field, this article gives a comprehensive review on the structure features, theoretical methods for stability and property prediction, processing routes, novel properties, and prospective applications of HECs. The challenges on processing, characterization, and property predictions are also emphasized. Finally, future directions for new material exploration, novel processing, fundamental understanding, in-depth characterization, and database assessments are given.

Motivation It has been shown that microRNAs (miRNAs) play key roles in variety of biological processes associated with human diseases. In Consideration of the cost and complexity of biological experiments, computational methods for predicting potential associations between miRNAs and diseases would be an effective complement. Results This paper presents a novel model of Inductive Matrix Completion for MiRNA–Disease Association prediction (IMCMDA). The integrated miRNA similarity and disease similarity are calculated based on miRNA functional similarity, disease semantic similarity and Gaussian interaction profile kernel similarity. The main idea is to complete the missing miRNA–disease association based on the known associations and the integrated miRNA similarity and disease similarity. IMCMDA achieves AUC of 0.8034 based on leave-one-out-cross-validation and improved previous models. In addition, IMCMDA was applied to five common human diseases in three types of case studies. In the first type, respectively, 42, 44, 45 out of top 50 predicted miRNAs of Colon Neoplasms, Kidney Neoplasms, Lymphoma were confirmed by experimental reports. In the second type of case study for new diseases without any known miRNAs, we chose Breast Neoplasms as the test example by hiding the association information between the miRNAs and Breast Neoplasms. As a result, 50 out of top 50 predicted Breast Neoplasms-related miRNAs are verified. In the third type of case study, IMCMDA was tested on HMDD V1.0 to assess the robustness of IMCMDA, 49 out of top 50 predicted Esophageal Neoplasms-related miRNAs are verified. Availability and implementation The code and dataset of IMCMDA are freely available at https://github.com/IMCMDAsourcecode/IMCMDA. Supplementary information Supplementary data are available at Bioinformatics online.

Distributed Denial of Service (DDoS) attacks in cloud computing environments are growing due to the essential characteristics of cloud computing. With recent advances in software-defined networking (SDN), SDN-based cloud brings us new chances to defeat DDoS attacks in cloud computing environments. Nevertheless, there is a contradictory relationship between SDN and DDoS attacks. On one hand, the capabilities of SDN, including software-based traffic analysis, centralized control, global view of the network, dynamic updating of forwarding rules, make it easier to detect and react to DDoS attacks. On the other hand, the security of SDN itself remains to be addressed, and potential DDoS vulnerabilities exist across SDN platforms. In this paper, we discuss the new trends and characteristics of DDoS attacks in cloud computing, and provide a comprehensive survey of defense mechanisms against DDoS attacks using SDN. In addition, we review the studies about launching DDoS attacks on SDN, as well as the methods against DDoS attacks in SDN.To the best of our knowledge, the contradictory relationship between SDN and DDoS attacks has not been well addressed in previous works. This work can help to understand how to make full use of SDN's advantages to defeat DDoS attacks in cloud computing environments and how to prevent SDN itself from becoming a victim of DDoS attacks, which are important for the smooth evolution of SDN-based cloud without the distraction of DDoS attacks.

Ustilaginoidea virens (Cooke) Takah is an ascomycetous fungus that causes rice false smut, a devastating emerging disease worldwide. Here we report a 39.4 Mb draft genome sequence of U. virens that encodes 8,426 predicted genes. The genome has B25% repetitive sequences that have been affected by repeat-induced point mutations. Evolutionarily, U. virens is close to the entomopathogenic Metarhizium spp., suggesting potential host jumping across kingdoms. U. virens possesses reduced gene inventories for polysaccharide degradation, nutrient uptake and secondary metabolism, which may result from adaptations to the specific floret infection and biotrophic lifestyles. Consistent with their potential roles in pathogenicity, genes for secreted proteins and secondary metabolism and the pathogen-host interaction database genes are highly enriched in the transcriptome during early infection. We further show that 18 candidate effectors can suppress plant hypersensitive responses. Together, our analyses offer new insights into molecular mechanisms of evolution, biotrophy and pathogenesis of U. virens.