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Creating good adaptation policies is critical to building complex autonomic systems since it is such policies that define the system configuration used in any given situation. While online approaches based on control theory and rulebased expert systems are possible solutions, each has its disadvantages. Here, a hybrid approach is described that uses modeling and optimization offline to generate suitable configurations, which are then encoded as policies that are used at runtime. The approach is demonstrated on the problem of providing dynamic management in virtualized consolidated server environments that host multiple multi-tier applications. Contributions include layered queuing models for Xen-based virtual machine environments, a novel optimization technique that uses a combination of bin packing and gradient search, and experimental results that show that automatic offline policy generation is viable and can be accurate even with modest computational effort.

Gold nanoparticles (AuNPs) can be readily synthesized and modified with chemical and biological molecules, making them attractive inorganic biomaterials for drug delivery and molecular diagnostics. The surface of AuNPs supports the efficient attachment of various biomacromolecules via chemisorption, chemical conjugation and electrostatic interaction. Based on advantages of facile surface modification and unique optical properties, AuNPs have been extensively used as drug carriers for the intracellular delivery of therapeutics as well as molecular nanoprobes for detection and monitoring of the target molecules of interest. In this review, we highlight advanced approaches in the biomedical applications of AuNPs such as gene and drug therapy, molecular diagnostics and imaging.

to encode a wide range of order-independent, sequential, and temporal logic and memory 26 operations. Furthermore, we show that these operators can be used to perform both digital and 27 analog computation, and record signaling dynamics and cellular states in a long-term, autonomous, 28 and minimally disruptive fashion. Finally, we show that the platform can be functionalized with The copyright holder for this preprint (which was not . http://dx.doi.org/10.1101/263657 doi: bioRxiv preprint first posted online Feb. 15, 2018; 3 Main Text: 40 Robust and scalable molecular recording and computation platforms in living cells are key to 41 enabling a broad range of bioengineering and biomedical applications. Unlike their silicon-based 42 counterparts that have access to large capacities of addressable memory registers, synthetic genetic 43 circuits currently have very limited information storage capacities and existing methods for 44 encoding information into cellular memory, as well as strategies for integrating such memory with 45 logic operations, are challenging to scale. 46 Genomic DNA is an ideal medium for biological memory since it is ubiquitously present, 47 naturally replicated at high fidelity within cells, and compatible with natural biological operations. 48 In recent years, several strategies for encoding biological information into DNA and integrating 49 these memories with cellular computers have been described (Farzadfard and Lu, 2014; Kalhor et 50 al., 2017; McKenna et al., 2016; Perli et al., 2016; Roquet et al., 2016; Siuti et al., 2013). However, 51 these methods remain limited in their encoding capacity and scalability. For example, site-specific 52 recombinases that flip or excise targeted DNA segments have been used to create digital memory, 53 sequential logic, and biological state machines in living cells (Roquet et al., 2016; Siuti et al., 54 2013). However, a different recombinase is required for every unique event that one wishes to 55 record, thus limiting the number of potential states that can be encoded into DNA memory. 56 Furthermore, distances between recombinase-recognition sites usually need to be several hundred 57 base pairs to achieve efficient recombination, thus increasing circuit size (Coppoolse et al., 2005; 58 Stark, 2017). Furthermore, recombinase sites must be pre-engineered into desired target sites, 59 which is time-and labor-intensive, especially if they are to be used in the genomic context. 60 To address these limitations, we previously developed the SCRIBE DNA writing and 61 molecular recording system, which uses in vivo single-stranded DNA expression to generate 62 precise mutations that accumulate into target genomic loci as a function of the magnitude and 63 duration of exposure to an input (Farzadfard and Lu, 2014). However, this approach has been 64 limited to bacteria thus far due to the requirement for specific recombination mechanisms. 65Alternative molecular recording strategies based on Cas9 ...

Abstract. Virtualization-based server consolidation requires runtime resource reconfiguration to ensure adequate application isolation and performance, especially for multitier services that have dynamic, rapidly changing workloads and responsiveness requirements. While virtualization makes reconfiguration easy, indiscriminate use of adaptations such as VM replication, VM migration, and capacity controls has performance implications. This paper demonstrates that ignoring these costs can have significant impacts on the ability to satisfy response-time-based SLAs, and proposes a solution in the form of a cost-sensitive adaptation engine that weighs the potential benefits of runtime reconfiguration decisions against their costs. Extensive experimental results based on live workload traces show that the technique is able to maximize SLA fulfillment under typical time-of-day workload variations as well as flash crowds, and that it exhibits significantly improved transient behavior compared to approaches that do not account for adaptation costs.

Magnetic nanoparticles have been subjected to extensive studies in the past few decades owing to their promising potentials in biomedical applications. The versatile intrinsic properties of magnetic nanoparticles enable their use in many biomedical applications. Recently, magnetic nanoparticles were utilized to control the cell's function. In addition, intracellular delivery of magnetic nanoparticles allowed cell's positioning by appropriate use of magnetic field and created cellular cluster. Furthermore, magnetic nanoparticles have been utilized to assemble more complex tissue structures than those that are achieved by conventional scaffold-based tissue engineering strategies. This review addresses recent work in the use magnetic nanoparticle for controlled tissue assembly and complex tissue formation.

Small-molecule control of antibody Nglycosylation in engineered mammalian cells The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Chang, Michelle M. et al. "Small-molecule control of antibody Nglycosylation in engineered mammalian cells." Nature Chemical Biology 15, 7 (May 2019

Highlights d DOMINO operators enable analog recording and continuous monitoring of cellular events d Various forms of logic can be built by layering multiple DOMINO operators d DOMINO allows online monitoring of DNA memory states without need for sequencing d DOMINO can be coupled with gene regulation for advanced memory and computation operations