A performance comparison of data-aware heuristics for scheduling jobs in mobile Grids

Given mobile devices ubiquity and capabilities, some researchers now consider them as resource providers of distributed environments called mobile Grids for running resource intensive software. Therefore, job scheduling has to deal with device singularities, such as energy constraints, mobility and unstable connectivity. Many existing schedulers consider at least one of these aspects, but their applicability strongly depends on information that is unavailable or difficult to estimate accurately, like job execution time. Other efforts do not assume knowing job CPU requirements but ignore energy consumption due to data transfer operations, which is not realistic for data-intensive applications. This work, on the contrary, considers the last as non negligible and known by the scheduler. Under these assumptions, we conduct a performance study of several traditional scheduling heuristics adapted to this environment, which are applied with the known information of jobs but evaluated along with job information unknown to the scheduler. Experiments are performed via a simulation software that employs hardware profiles derived from real mobile devices. Our goal is to contribute to better understand both the capabilities and limitations of this kind of schedulers in the incipient area of mobile Grids.Sociedad Argentina de Informática e Investigación Operativa (SADIO

A performance comparison of data-aware heuristics for scheduling jobs in mobile Grids

Given mobile devices ubiquity and capabilities, some researchers now consider them as resource providers of distributed environments called mobile Grids for running resource intensive software. Therefore, job scheduling has to deal with device singularities, such as energy constraints, mobility and unstable connectivity. Many existing schedulers consider at least one of these aspects, but their applicability strongly depends on information that is unavailable or difficult to estimate accurately, like job execution time. Other efforts do not assume knowing job CPU requirements but ignore energy consumption due to data transfer operations, which is not realistic for data-intensive applications. This work, on the contrary, considers the last as non negligible and known by the scheduler. Under these assumptions, we conduct a performance study of several traditional scheduling heuristics adapted to this environment, which are applied with the known information of jobs but evaluated along with job information unknown to the scheduler. Experiments are performed via a simulation software that employs hardware profiles derived from real mobile devices. Our goal is to contribute to better understand both the capabilities and limitations of this kind of schedulers in the incipient area of mobile Grids.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Mobile Devices-aware Refactorings for Scientific Computational Kernels

The increasing number of mobile devices with ever-growing processing capabilities, make them interesting for scientific applications development. However, we must take into account that mobile devices still have limited capabilities compared to fixed devices. Besides, mobile devices rely on battery as energy supply. For these reasons, this paper analyzes different micro-benchmarks battery consumption given by common operations in scientific computational kernels. Indirectly, we propose good programming practices or code refactorings in order to minimize mobile devices battery consumption.Sociedad Argentina de Informática e Investigación Operativ

Highly conductive microporous carbon fibers by electrospinning of lignin/phosphoric acid/ethanol solutions

This contribution reports the preparation of electrospun lignin-based carbon fibers at different carbonization temperatures and the influence of heat treatments at temperatures ranging from 900 to 1600 ºC. The influence of the addition of phosphoric acid in the initial electrospinning solution on the structural ordering, electrical conductivity and porosity development of the final carbon fibers is studied in detail. Alcell lignin fibers were electrospun using a coaxial electrospinning device following the procedure previously reported by our research group. Electrospun H3PO4-lignin fibers were prepared in the same device by addition of phosphoric acid to the lignin solution using mass ratios of 0.1 and 0.3. The electrospun fibers were stabilized in air at 200 ºC, using a slow heating rate and carbonized under inert atmosphere at temperatures between 500 and 900 ºC. In addition, the fibers carbonized at 900 ºC were heat treated at temperatures between 1200 and 1600 ºC. The high temperature heat treatment removes most of the heteroatoms (O, P) for both carbon fibers. However, the surface area of the phosphorous containing carbon fibers is mostly preserved after the heat treatment, while a large porosity shrinkage is observed for the pure lignin-derived fibers. Thus, microporous carbon fibers with large electrical conductivity values have been obtained by heat treatment at 1600 ºC of P-containing electrospun carbon fibers.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Biomass waste carbon materials for post-combustion CO2 capture

Low-carbon energy systems based on carbon capture and storage (CCS) have become of great interest due to the imperative necessity of mitigating the carbon footprint derived from the currently fossil fuels-based energy technologies. In this sense, post-combustion CO2 adsorption over porous solids results particularly attractive from several viewpoints. In a green context, the use of carbon-based materials as adsorbents would entail important economic and environmental profits, such as the valorization of different types of biomass and lignocellulosic waste. In this work, six carbon materials were prepared from four types of low cost biomass residues. Electrospun carbon fibers, FCL, and a char, GCL, were obtained from Alcell® lignin. Two activated carbons, GAS and GAWBa, resulted from physical activation of olive stones and plywood waste, respectively. Finally, another activated carbon, GAL, and an activated carbon cloth, CAD, were synthesized by chemical activation of lignin and a denim cloth. These materials were evaluated as potential adsorbents for CO2 capture under post-combustion conditions by means of equilibrium and dynamic experiments (fixed-bed system). Moreover, the regeneration capacity of the samples was also studied. At 101.3 kPa, the samples displayed CO2 capacities between 2.0 and 3.1 mmol/g. Meaningfully, the uptake values, at typical CO2 pressures in post-combustion applications (c.a. 15 kPa), remain in the range of 0.7 to 1.2 mmol/g, which are comparable to those of other complex and appealing materials. Additionally, a thorough characterization of the porous structure of the different adsorbents provided new insights into the influence of the pore size distribution on the CO2 capture capacity. CO2 retention capacities correlate well with the narrow micropore volume derived from the CO2 adsorption data at 0 ºC, VDRCO2, at 101.3 kPa (Figure 2). In contrast, at 15 kPa, analysis of the cumulative pore volumes of the samples pointed out that only pores of sizes below 0.7 nm are relevant for adsorption. Under dynamic conditions, the studied materials also showed remarkable adsorptive behaviors. For instance, the lignin-derived carbon fiber (FCL) exhibited a capacity value higher than 1.3 mmol/g.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A performance comparison of data-aware heuristics for scheduling jobs in mobile Grids

Given mobile devices ubiquity and capabilities, some researchers now consider them as resource providers of distributed environments called mobile Grids for running resource intensive software. Therefore, job scheduling has to deal with device singularities, such as energy constraints, mobility and unstable connectivity. Many existing schedulers consider at least one of these aspects, but their applicability strongly depends on information that is unavailable or difficult to estimate accurately, like job execution time. Other efforts do not assume knowing job CPU requirements but ignore energy consumption due to data transfer operations, which is not realistic for data-intensive applications. This work, on the contrary, considers the last as non negligible and known by the scheduler. Under these assumptions, we conduct a performance study of several traditional scheduling heuristics adapted to this environment, which are applied with the known information of jobs but evaluated along with job information unknown to the scheduler. Experiments are performed via a simulation software that employs hardware profiles derived from real mobile devices. Our goal is to contribute to better understand both the capabilities and limitations of this kind of schedulers in the incipient area of mobile Grids.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Human red blood cells at work: identification and visualization of erythrocytic eNOS activity in health and disease

A nitric oxide synthase (NOS)-like activity has been demonstrated in human red blood cells (RBCs), but doubts about its functional significance, isoform identity and disease relevance remain. Using flow cytometry in combination with the NO-imaging probe DAF-FM we find that all blood cells form NO intracellularly, with a rank order of monocytes > neutrophils > lymphocytes > RBCs > platelets. The observation of a NO-related fluorescence within RBCs was unexpected given the abundance of the NO-scavenger oxyhemoglobin. Constitutive normoxic NO formation was abolished by NOS inhibition and intracellular NO scavenging, confirmed by laser-scanning microscopy and unequivocally validated by detection of the DAF-FM reaction product with NO using HPLC and LC-MS/MS. Employing immunoprecipitation, ESI-MS/MS-based peptide sequencing and enzymatic assay we further demonstrate that human RBCs contain an endothelial NOS (eNOS) that converts L-3H-Arginine to L-3H-Citrulline in a Ca2+/Calmodulin-dependent fashion. Moreover, in patients with coronary artery disease, red cell eNOS expression and activity are both lower than in age-matched healthy individuals and correlate with the degree of endothelial dysfunction. Thus, human RBCs constitutively produce NO under normoxic conditions via an active eNOS isoform the activity of which is compromised in patients with coronary artery disease

Characterization of Antimicrobial Susceptibility of Bacterial Biofilms on Biological Tissues

abstract: Prosthetic joint infection (PJI) is a devastating complication associated with total joint arthroplasty that results in high cost and patient morbidity. There are approximately 50,000 PJIs per year in the US, imposing a burden of about $5 billion on the healthcare system. PJI is especially difficult to treat because of the presence of bacteria in biofilm, often highly tolerant to antimicrobials. Treatment of PJI requires surgical debridement of infected tissues, and local, sustained delivery of antimicrobials at high concentrations to eradicate residual biofilm bacteria. However, the antimicrobial concentrations required to eradicate biofilm bacteria grown in vivo or on tissue surfaces have not been measured. In this study, an experimental rabbit femur infection model was established by introducing a variety of pathogens representative of those found in PJIs [Staphylococcus Aureus (ATCC 49230, ATCC BAA-1556, ATCC BAA-1680), Staphylococcus Epidermidis (ATCC 35984, ATCC 12228), Enterococcus Faecalis (ATCC 29212), Pseudomonas Aeruginosa (ATCC 27853), Escherichia Coli (ATCC 25922)]. Biofilms of the same pathogens were grown in vitro on biologic surfaces (bone and muscle). The ex vivo and in vitro tissue minimum biofilm eradication concentration (MBEC; the level required to eradicate biofilm bacteria) and minimum inhibitory concentration (MIC; the level required to inhibit planktonic, non-biofilm bacteria) were measured using microbiological susceptibility assays against tobramycin (TOB) and vancomycin (VANC) alone or in 1:1 weight combination of both (TOB+VANC) over three exposure durations (6 hour, 24 hour, 72 hour). MBECs for all treatment combinations (pathogen, antimicrobial used, exposure time, and tissue) were compared against the corresponding MIC values to compare the relative susceptibility increase due to biofilm formation. Our data showed median in vitro MBEC to be 100-1000 times greater than the median MIC demonstrating the administration of local antimicrobial doses at MIC level would not kill the persisting bacteria in biofilm. Also, administering dual agent (TOB+VANC) showed median MBEC values to be comparable or lower than the single agents (TOB or VANC)Dissertation/ThesisMasters Thesis Bioengineering 201

In vivo study of the bioavailability and metabolic profile of (poly)phenols after sous-vide artichoke consumption

Artichokes are a rich source of (poly)phenols, mainly caffeoylquinic acids, but little is known about their bioavailability from this source. This study investigated the absorption, metabolism and excretion of (poly)phenols after sous-vide artichoke consumption (5776 µmol of (poly)phenols) by healthy volunteers. Seventy-six (poly)phenol metabolites were identified by UHPLC-MS/MS using authentic standards, including acyl-quinic acids plus C6–C3, C6–C1, C6–C2, C6–C1–N, C6–C0 metabolites, and their phase-II conjugates. The major metabolites were 3ʹ-methoxy-4ʹ-hydroxycinnamic acid, 3ʹ-methoxycinnamic acid-4ʹ-sulfate, and 4ʹ-hydroxycinnamic acid-3ʹ-sulfate, which appeared early in plasma (Tmax 6 h). The 24 h urinary recovery averaged 8.9% (molar basis) of the (poly)phenols consumed. Hepatic beta-oxidation of 3ʹ,4ʹ-dihydroxycinnamic acid and methylated conjugates occurred, but was limited (<0.04%). 3ʹ-Methylation exceeded 4ʹ-methylation and interindividual variability was high, especially for gut microbial metabolites (up to 168-fold)

Consumption of Stilbenes and Flavonoids is Linked to Reduced Risk of Obesity Independently of Fiber Intake

BACKGROUND: Polyphenol consumption is implicated in gut microbiome composition and improved metabolic outcomes, but it is unclear whether the effect is independent of dietary fiber. METHODS: We investigated the links between (poly)phenol intake, gut microbiome composition (16s RNA) and obesity independently of fiber intake in UK women (n = 1810) and in a small group of UK men (n = 64). RESULTS: (Poly)phenol intakes correlated with microbiome alpha diversity (Shannon Index) after adjusting for confounders and fiber intake. Moreover, flavonoid intake was significantly correlated with the abundance of Veillonella, (a genus known to improve physical performance), and stilbene intake with that of butyrate-producing bacteria (Lachnospira and Faecalibacterium). Stilbene and flavonoid intake also correlated with lower odds of prevalent obesity (Stilbenes: Odds Ratio (95% Confidence Interval) (OR(95%CI)) = 0.80 (0.73, 0.87), p = 4.90 × 10-7; Flavonoids: OR(95%CI) = 0.77 (0.65, 0.91), p = 0.002). Formal mediation analyses revealed that gut microbiome mediates ~11% of the total effect of flavonoid and stilbene intake on prevalent obesity. CONCLUSIONS: Our findings highlight the importance of (poly)phenol consumption for optimal human health