Dependable virtualised systems

Virtual machines and containers are widely used in data centres and in the cloud for software deployment and management. Their popularity is based on higher capacity utilisation, lower maintenance costs, and better scalability by creating an abstraction layer on top of physical hardware. The economics and scalability of virtualised applications require that the workloads of multiple customers can run on the same hardware with low overhead without compromising security. To address this need, in this work we introduce a new set of IO middleware that allows users to run smaller containers and virtual machines and deploy them in a more secure manner. The presented contributions can be summarised as follows: • CNTR provides a way to extend application containers at runtime with tools deployed in a different container. In this way, you can create "slim" images that contain only the actual application, while all the tools needed for monitoring, testing, and debugging reside in a "fat" image that only needs to be deployed when needed. CNTR achieves this by creating a nested namespace in the application container that proxies files from a remote container using a FUSE filesystem. • VMSH allows users to attach services to running virtual machines independent of the guest userspace and without any pre-installed agents. Similar to CNTR this allows developers to build more light-weight virtual machines by deploying additional services in a separate user-provided file system image on-demand. VMSH achieves this by side-loading kernel code into the guest and mounting a filesystem based on its own block device in a light-weight container without affecting the applications in the VM. • RKT-IO leverages trusted execution environments to run workloads in containers and virtual machines to protect them from other tenants and the cloud provider on the same host, but without sacrificing on I/O performance that is usually degraded by this protection. It does so by providing a userspace network and storage I/O stack in the form of a library OS based on Linux that directly accesses the hardware from within the TEE by-passing the host kernel

Annual Report 2001/2002 / Department for Computer Science

Selbstdarstellung des Instituts für Informatik der BTU Cottbus und Berichte der Lehrstühle für die Jahre 2001 und 2002.Presentation of the Department for Computer Science of the BTU Cottbus and reports of the chairs at the department for the years 2001 and 2002

Annual Report 2003/2005 / Department for Computer Science, Information and Media Technology

Selbstdarstellung des Instituts für Informatik, Informations- und Medientechnik der BTU Cottbus und Berichte der Lehrstühle für die Jahre 2003, 2004 und 2005.Presentation of the Department for Computer Science, Information and Media Technology of the BTU Cottbus and reports of the chairs at the department for the years 2003, 2004 and 2005

Linking stem cell function and growth pattern of intestinal organoids

Intestinal stem cells (ISCs) require well-defined signals from their environment in order to carry out their specific functions. Most of these signals are provided by neighboring cells that form a stem cell niche, whose shape and cellular composition self-organize. Major features of this self-organization can be studied in ISC-derived organoid culture. In this system, manipulation of essential pathways of stem cell maintenance and differentiation results in well-described growth phenotypes. We here provide an individual cell-based model of intestinal organoids that enables a mechanistic explanation of the observed growth phenotypes. In simulation studies of the 3D structure of expanding organoids, we investigate interdependences between Wnt- and Notch-signaling which control the shape of the stem cell niche and, thus, the growth pattern of the organoids. Similar to in vitro experiments, changes of pathway activities alter the cellular composition of the organoids and, thereby, affect their shape. Exogenous Wnt enforces transitions from branched into a cyst-like growth pattern; known to occur spontaneously during long term organoid expansion. Based on our simulation results, we predict that the cyst-like pattern is associated with biomechanical changes of the cells which assign them a growth advantage. The results suggest ongoing stem cell adaptation to in vitro conditions during long term expansion by stabilizing Wnt-activity. Our study exemplifies the potential of individual cell-based modeling in unraveling links between molecular stem cell regulation and 3D growth of tissues. This kind of modeling combines experimental results in the fields of stem cell biology and cell biomechanics constituting a prerequisite for a better understanding of tissue regeneration as well as developmental processes

The Adhesion G-Protein-Coupled Receptor GPR115/ADGRF4 Regulates Epidermal Differentiation and Associates with Cytoskeletal KRT1

Among the 33 human adhesion G-protein-coupled receptors (aGPCRs), a unique subfamily of GPCRs, only ADGRF4, encoding GPR115, shows an obvious skin-dominated transcriptomic profile, but its expression and function in skin is largely unknown. Here, we report that GPR115 is present in a small subset of basal and in most suprabasal, noncornified keratinocytes of the stratified epidermis, supporting epidermal transcriptomic data. In psoriatic skin, characterized by hyperproliferation and delayed differentiation, the expression of GPR115 and KRT1/10, the fundamental suprabasal keratin dimer, is delayed. The deletion of ADGRF4 in HaCaT keratinocytes grown in an organotypic mode abrogates KRT1 and reduces keratinocyte stratification, indicating a role of GPR115 in epidermal differentiation. Unexpectedly, endogenous GPR115, which is not glycosylated and is likely not proteolytically processed, localizes intracellularly along KRT1/10-positive keratin filaments in a regular pattern. Our data demonstrate a hitherto unknown function of GPR115 in the regulation of epidermal differentiation and KRT1

msoos/cryptominisat: CryptoMiniSat 5.7.1

<p>Removing LSIDS, as it was interfering with performance.</p&gt