CloudScope: diagnosing and managing performance interference in multi-tenant clouds

© 2015 IEEE.Virtual machine consolidation is attractive in cloud computing platforms for several reasons including reduced infrastructure costs, lower energy consumption and ease of management. However, the interference between co-resident workloads caused by virtualization can violate the service level objectives (SLOs) that the cloud platform guarantees. Existing solutions to minimize interference between virtual machines (VMs) are mostly based on comprehensive micro-benchmarks or online training which makes them computationally intensive. In this paper, we present CloudScope, a system for diagnosing interference for multi-tenant cloud systems in a lightweight way. CloudScope employs a discrete-time Markov Chain model for the online prediction of performance interference of co-resident VMs. It uses the results to optimally (re)assign VMs to physical machines and to optimize the hypervisor configuration, e.g. the CPU share it can use, for different workloads. We have implemented CloudScope on top of the Xen hypervisor and conducted experiments using a set of CPU, disk, and network intensive workloads and a real system (MapReduce). Our results show that CloudScope interference prediction achieves an average error of 9%. The interference-aware scheduler improves VM performance by up to 10% compared to the default scheduler. In addition, the hypervisor reconfiguration can improve network throughput by up to 30%

Geochemical characteristics and mantle sources of the Oligo-Miocene primitive basalts from Sardinia: The role of subduction components.

During the Oligo-Miocene, the Island of Sardinia was covered by the products of voluminous magmatic activity, with a typical subduction-related signature. The mafic rocks of the Montresta (north) and Arcuentu (south) volcanic districts include primitive high MgO basalts whose trace element and Sr-, Nd- and Pb-isotope compositions constrain the nature and role of subduction-related components in the Tertiary Sardinian volcanism. The geochemical and isotopic data require an approximate degree of partial melting of 15% of a MORB-like depleted mantle prior to enrichment, and the input of two subduction components in the mantle wedge consisting of fluids from subducted oceanic crust (altered MORB) and fluids from subducted sediments. Ratios among trace elements which are variably compatible with fluid and melt phases (i.e. Th/Pb, Th/Nd and Sr/Nd) exclude the contribution of melts from the subducted slab. Models based on isotopic ratios indicate that the pre-subduction depleted mantle source of Sardinia magmas was enriched by 0.1-0.5% MORB fluid and less than 0.1% sediment fluid. The geochemical and isotopic compositions of the Montresta volcanic rocks are homogeneous, whereas those of the Arcuentu show quite heterogeneous characters, suggesting variations in mantle source over the long time-span (about 13 Ma) of volcanic activity in this district

Sequential bilateral cochlear implant: long-term speech perception results in children first implanted at an early age

Purpose: The study aims to assess the benefit of sequential bilateral cochlear implantation in children with congenital bilateral profound hearing loss, submitted to the first implant at an early age. Methods: We enrolled all the bilateral sequential cochlear implanted children who received the first implant within 48 months and the second within 12 years of age at our Institution. The children were submitted to disyllabic word recognition tests and Speech Reception Threshold (SRT) assessment using the OLSA matrix sentence test with the first implanted device (CI1), with the second implanted device (CI2), and with both devices (CIbil). Furthermore, we measured the datalogging of both devices. Then we calculated the binaural SRT gain (b-SRTgain) and checked the correlations between speech perception results and the b-SRTgain with the child’s age at CI1 and CI2, DELTA and the datalogging reports. Results: With the bilateral electric stimulation, we found a significant improvement in disyllabic word recognition scores and in SRT. Moreover, the datalogging showed no significant differences in the time of use of CI1 and CI2. We found significant negative correlations between speech perception abilities with CI2 and age at CI2 and DELTA, and between the SRT with CI1 and the b-SRTgain. Conclusions: From this study we can conclude that in a sequential CI procedure, even if a short inter-implant delay and lower ages at the second surgery can lead to better speech perception with CI2, children can benefit from bilateral stimulation independently of age at the second surgery and the DELTA

Conventional MRI-Derived Biomarkers of Adult-Type Diffuse Glioma Molecular Subtypes: A Comprehensive Review

The introduction of molecular criteria into the classification of diffuse gliomas has added interesting practical implications to glioma management. This has created a new clinical need for correlating imaging characteristics with glioma genotypes, also known as radiogenomics or imaging genomics. Although many studies have primarily focused on the use of advanced magnetic resonance imaging (MRI) techniques for radiogenomics purposes, conventional MRI sequences remain the reference point in the study and characterization of brain tumors. A summary of the conventional imaging features of glioma molecular subtypes should be useful as a tool for daily diagnostic brain tumor management. Hence, this article aims to summarize the conventional MRI features of glioma molecular subtypes in light of the recent literature

Changing the approach to sustainable constructions: An adaptive mix-design calibration process for earth composite materials

One major drawback of excavation earth-based composite construction materials is the variability in excavation earth characteristics from site to site. This variability can affect certain physical properties, and, in turn, the design models used to create a structure. To solve this problem, a methodology has been developed to predict the physical properties of earth-based composites for any mix-design variation, which enables a robust structural design process. This new methodology has been tested for Shot-earth, a new class of earth-based composite material made using high rates of excavation earth, aggregates, and a low rate of stabilization if needed. Shot-earth is placed using a high-speed dry-mix process. The methodology was tested by preparing small, inexpensive specimens through a process that simulates the dry-process used to fabricate Shot-earth in the field. An adaptive technique, used in conjunction with the experimental methodology, allows for the identification of the variant of possible Shot-earth mix-designs that provides optimal physical properties for a specific project. This technique is potentially applicable to any type of earth-based composite. The proposed methodology’s reliability enables a fast and cost-effective detailing of Shot-earth constructions

Biomarker Discovery In Chronic Obstructive Pulmonary Disease (COPD) Using Epithelial Lining Fluid:A Proteomic Approach

RATIONALE Chronic Obstructive Pulmonary Disease (COPD) is the third most frequent disease worldwide with increasing mortality. Cigarette smoking is the principle risk factor and 15-20% of smokers develop COPD. Epithelial Lining Fluid (ELF) covers the internal part of the airways and can be collected during bronchoscopy. ELF appears to be well-suited for proteomic analysis, since it contains a higher concentration of proteins (150-300 μg /mL) than other lung fluids and can be obtained from different locations of the lungs. No comprehensive proteomic analysis of human ELF has been performed to date, which makes ELF a highly interesting fluid for biomarker discovery in COPD. AIM To discover proteins that change in abundance in ELF from COPD patients versus healthy controls using a quantitative proteomics approach. METHODS The ELF proteome from COPD patients and healthy controls was studied by 1D polyacrylamide gel electrophoresis in the presence of SDS followed by in-gel tryptic digestion to establish the methodology and assess the feasibility of such an approach. Approximately 40 gel slices were obtained from each lane of the gel (corresponding to one patient). Digested samples were analyzed by nanoChip-LC-MS/MS using an ion trap. We performed a quantitative pilot study of ELF from 4 COPD patients and 4 healthy controls (table 1) to test for statistically significant differences in protein levels. ELF samples were digested by trypsin, labeled with stable isotope-containing reagents (iTRAQ®, 8-plex) and processed by strong cation-exchange chromatography followed by nanoLC-MS/MS. In order to validate the results, a second quantitative analysis of an independent sample set (4 COPD vs 4 healthy) using the same methodological approach was done. RESULTS The 1D electrophoretic approach resulted in more than 300 identified proteins. Most of the identified proteins were present in both COPD and healthy samples, although some proteins were only identified either in healthy control or in COPD samples. The quantitative studies showed that a number of proteins was significantly different between ELF of COPD patients and controls, including 4 up-regulated proteins in common in both studies. CONCLUSIONS This is the first study in ELF of COPD patients and healthy controls in which such a large number of proteins has been identified. The obtained results show the feasibility of this proteomic approach and the possibility to discover proteins that are differentially expressed in ELF of COPD patients and controls. We are currently validating these proteins further by western blot and immunohistochemistry

Tracking the transfer of antimicrobial resistance genes from raw materials to sourdough breads

The present study hypothesizes that raw materials used in bread making can transfer antibiotic resistance genes (ARGs) to processed breads. Four types of flour and four types of semolina were purchased from supermarkets and inoculated with a commercial dried sourdough starter to make breads. The microbiological characteristics of all raw materials and fermented doughs were investigated. The levels of yeasts and lactic acid bacteria (LAB) increased up to 107 CFU/g. The values of pH decreased to 4.54–4.86 while total titratable acidity increased inversely. All unprocessed and processed samples, including breads, were analyzed by a molecular approach to detect bacterial and fungal DNAs and 17 antibiotic resistance genes for penicillins, macrolides, tetracyclines, and chloramphenicol. Illumina technology showed that the operational taxonomy units (OTUs) identified from unprocessed wheat milling products, fermented doughs, and baked products mainly belonged to Acetobacteraceae. Enterococci were present in all doughs. After baking, the relative abundance (RA)% of Enterococcus and Acetobacteraceae decreased. The DNA analyzed for fungal composition showed that Kazachstania humilis dominated dried sourdough starter and doughs, and its OTUs were also detected at high RA% in baked products. The search for ARGs revealed that all samples analyzed did not show resistance to penicillins, chloramphenicol, and macrolides. However, three of the semolinas included in this study (S1, S3 and S4) and the corresponding doughs (SD1, SD3 and SD4) were positive for tet(A) and tet(B) resistance genes. This work indicated that breads have a limited role in the dissemination of ARGs

Tracking the transfer of antimicrobial resistance genes from raw materials to sourdough breads

The present study hypothesizes that raw materials used in bread making can transfer antibiotic resistance genes (ARGs) to processed breads. Four types of flour and four types of semolina were purchased from supermarkets and inoculated with a commercial dried sourdough starter to make breads. The microbiological characteristics of all raw materials and fermented doughs were investigated. The levels of yeasts and lactic acid bacteria (LAB) increased up to 107 CFU/g. The values of pH decreased to 4.54–4.86 while total titratable acidity increased inversely. All unprocessed and processed samples, including breads, were analyzed by a molecular approach to detect bacterial and fungal DNAs and 17 antibiotic resistance genes for penicillins, macrolides, tetracyclines, and chloramphenicol. Illumina technology showed that the operational taxonomy units (OTUs) identified from unprocessed wheat milling products, fermented doughs, and baked products mainly belonged to Acetobacteraceae. Enterococci were present in all doughs. After baking, the relative abundance (RA)% of Enterococcus and Acetobacteraceae decreased. The DNA analyzed for fungal composition showed that Kazachstania humilis dominated dried sourdough starter and doughs, and its OTUs were also detected at high RA% in baked products. The search for ARGs revealed that all samples analyzed did not show resistance to penicillins, chloramphenicol, and macrolides. However, three of the semolinas included in this study (S1, S3 and S4) and the corresponding doughs (SD1, SD3 and SD4) were positive for tet(A) and tet(B) resistance genes. This work indicated that breads have a limited role in the dissemination of ARG