Microservice Transition and its Granularity Problem: A Systematic Mapping Study

Microservices have gained wide recognition and acceptance in software industries as an emerging architectural style for autonomic, scalable, and more reliable computing. The transition to microservices has been highly motivated by the need for better alignment of technical design decisions with improving value potentials of architectures. Despite microservices' popularity, research still lacks disciplined understanding of transition and consensus on the principles and activities underlying "micro-ing" architectures. In this paper, we report on a systematic mapping study that consolidates various views, approaches and activities that commonly assist in the transition to microservices. The study aims to provide a better understanding of the transition; it also contributes a working definition of the transition and technical activities underlying it. We term the transition and technical activities leading to microservice architectures as microservitization. We then shed light on a fundamental problem of microservitization: microservice granularity and reasoning about its adaptation as first-class entities. This study reviews state-of-the-art and -practice related to reasoning about microservice granularity; it reviews modelling approaches, aspects considered, guidelines and processes used to reason about microservice granularity. This study identifies opportunities for future research and development related to reasoning about microservice granularity.Comment: 36 pages including references, 6 figures, and 3 table

MeCP2 deficiency results in robust Rett-like behavioural and motor deficits in male and female rats

Since the identification of MECP2 as the causative gene in the majority of Rett Syndrome (RTT) cases, transgenic mouse models have played a critical role in our understanding of this disease. The use of additional mammalian RTT models offers the promise of further elucidating critical early mechanisms of disease as well as providing new avenues for translational studies. We have identified significant abnormalities in growth as well as motor and behavioural function in a novel zincfinger nuclease model of RTT utilizing both male and female rats throughout development. Male rats lacking MeCP2 (Mecp2ZFN/y) were noticeably symptomatic as early as postnatal day 21, with most dying by postnatal day 55, while females lacking one copy of Mecp2 (Mecp2ZFN/þ) displayed a more protracted disease course. Brain weights of Mecp2ZFN/y and Mecp2ZFN/þ rats were significantly reduced by postnatal day 14 and 21, respectively. Early motor and breathing abnormalities were apparent in Mecp2ZFN/y rats, whereas Mecp2ZFN/þ rats displayed functional irregularities later in development. The large size of this species will provide profound advantages in the identification of early disease mechanisms and the development of appropriately timed therapeutics. The current study establishes a foundational basis for the continued utilization of this rat model in future RTT research

Upregulation of mGlu2 receptors via NF-kB p65 acetylation is involved in the proneurogenic and antidepressant effects of acetyl-L-carnitine

Acetyl-L-carnitine (ALC) is a naturally occurring molecule with an important role in cellular bioenergetics and as donor of acetyl groups to proteins, including NF-kappa B p65. In humans, exogenously administered ALC has been shown to be effective in mood disturbances, with a good tolerability profile. No current information is available on the antidepressant effect of ALC in animal models of depression and on the putative mechanism involved in such effect. Here we report that ALC is a proneurogenic molecule, whose effect on neuronal differentiation of adult hippocampal neural progenitors is independent of its neuroprotective activity. The in vitro proneurogenic effects of ALC appear to be mediated by activation of the NF-kappa B pathway, and in particular by p65 acetylation, and subsequent NF-kappa B-mediated upregulation of metabotropic glutamate receptor 2 (mGlu2) expression. When tested in vivo, chronic ALC treatment could revert depressive-like behavior caused by unpredictable chronic mild stress, a rodent model of depression with high face validity and predictivity, and its behavioral effect correlated with upregulated expression of mGlu2 receptor in hippocampi of stressed mice. Moreover, chronic, but not acute or subchronic, drug treatment significantly increased adult born neurons in hippocampi of stressed and unstressed mice. We now propose that this mechanism could be potentially involved in the antidepressant effect of ALC in humans. These results are potentially relevant from a clinical perspective, as for its high tolerability profile ALC may be ideally employed in patient subpopulations who are sensitive to the side effects associated with classical antidepressant

Modulation of the absorption coefficient at 13 μm in Ge/SiGe multiple quantum well heterostructures on silicon

We report modulation of the absorption coefficient at 1.3 μm in Ge/SiGe multiple quantum well heterostructures on silicon via the quantum-confined Stark effect. Strain engineering was exploited to increase the direct optical bandgap in the Ge quantum wells. We grew 9 nm-thick Ge quantum wells on a relaxed Si0.22Ge0.78 buffer and a contrast in the absorption coefficient of a factor of greater than 3.2 was achieved in the spectral range 1290–1315 nm

On Predicting Mössbauer Parameters of Iron-Containing Molecules with Density-Functional Theory

The performance of six frequently used density functional theory (DFT) methods (RPBE, OLYP, TPSS, B3LYP, B3LYP*, and TPSSh) in the prediction of Mössbauer isomer shifts(δ) and quadrupole splittings (ΔEQ) is studied for an extended and diverse set of Fe complexes. In addition to the influence of the applied density functional and the type of the basis set, the effect of the environment of the molecule, approximated with the conducting-like screening solvation model (COSMO) on the computed Mössbauer parameters, is also investigated. For the isomer shifts the COSMO-B3LYP method is found to provide accurate δ values for all 66 investigated complexes, with a mean absolute error (MAE) of 0.05 mm s–1 and a maximum deviation of 0.12 mm s–1. Obtaining accurate ΔEQ values presents a bigger challenge; however, with the selection of an appropriate DFT method, a reasonable agreement can be achieved between experiment and theory. Identifying the various chemical classes of compounds that need different treatment allowed us to construct a recipe for ΔEQ calculations; the application of this approach yields a MAE of 0.12 mm s–1 (7% error) and a maximum deviation of 0.55 mm s–1 (17% error). This accuracy should be sufficient for most chemical problems that concern Fe complexes. Furthermore, the reliability of the DFT approach is verified by extending the investigation to chemically relevant case studies which include geometric isomerism, phase transitions induced by variations of the electronic structure (e.g., spin crossover and inversion of the orbital ground state), and the description of electronically degenerate triplet and quintet states. Finally, the immense and often unexploited potential of utilizing the sign of the ΔEQ in characterizing distortions or in identifying the appropriate electronic state at the assignment of the spectral lines is also shown

Fabrication of thick silicon dioxide layers for thermal isolation

This paper reports a method of fabricating very thick (10–100 µm) silicon dioxide layers for thermal isolation without the need for very long deposition or oxidation. Deep reactive ion etching (DRIE) is used to create high-aspect-ratio trenches and silicon pillars, which are then oxidized and/or refilled with LPCVD oxide to create oxide layers as thick as the DRIE allows. Stiffeners are used to provide support for the pillars during oxidation. Thermal tests show that such thick silicon dioxide layers can effectively thermally isolate heated structures from neighboring structures within a distance of hundreds of microns. The thermal conductivity of the thick SiO2 is measured to be ∼1.1 W (m K)−1. Such SiO2 diaphragms of thickness 50–60 µm can sustain an extrinsic shear stress up to 3–5 MPa.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/49045/2/jmm4_6_002.pd