98 research outputs found

    Optimizing Memory Usage in L4-Based Microkernel

    Get PDF
    Memory allocation is a critical aspect of any modern operating system kernel because it must run continuously for long periods of time, therefore memory leaks and inefficiency must be eliminated. This paper presents different memory management algorithms and their aplicability to an L4-based microkernel. We aim to reduce memory usage and increase the performance of allocation and deallocation of memory

    HISTO-ANATOMICAL AND CHROMATOGRAPHIC RESEARCHES ON ZIZIPHORA CAPITATA L. (LAMIACEAE) SPECIES

    Get PDF
    Concerning Ziziphora capitata L. (Lamiaceae) species, the paper presents the histo-anatomical analysis of root, aboveground stem and leaf, along with the chromatographic investigations of the polyphenols in the aerial parts. Caffeic acid (126.2 μg/mL) and rutin (171.3 μg/mL) were identified in the 20% methanolic extract of Ziziphorae capitatae herba, by thin-layer chromatography coupled with photodensitometry

    PRELIMINARY CHROMATOGRAPHIC INVESTIGATION OF FOUR STACHYS SPP. (LAMIACEAE) FROM OLTENIA FLORA

    Get PDF
    Concerning four Stachys spp. (Lamiaceae) from the Oltenia flora, the paper highlights the polyphenolic content of aerial parts through high-performance thin-layer chromatography coupled with photodensitometry. Chlorogenic acid (CA) was identified and quantified in all 20% methanolic extracts of Stachydisherba. The highest CA amount was determined in S. recta (59.88 mg%), followed by S. sylvatica (32.90 mg%), S. officinalis (31.34 mg%), and S. germanica (25.16 mg%), respectively

    Potentialities of LL37 for Wound Healing Applications: Study of Its Activity in Synergy with Biodegradable Composites Made of PVA and CA

    Get PDF
    Wound healing is a dynamic and complex process that results from the interaction between cytokines, growth factors, blood components and the extracellular matrix. Conventional dressings made of natural or synthetic materials have only the ability to manage the wound and protect it from repeated trauma. With the advancement of technology, wound dressings have evolved and are now capable of intervening in the healing process by targeting specific features of the wound, aside from protecting the wounded site. In this work, bioactive dressings capable of promoting healing and fighting infection in chronic wounds were explored. Various antimicrobial biomolecules were examined in light of their pathogen fighting skills and immunoregulatory potentialities. Dressing production processes were also investigated. Biodegradable composite dressings made of poly(vinyl alcohol), polycaprolactone, chitosan and cellulose blends were our main focus. The goal was to evaluate the synergistic effect of biomolecules and biodegradable polymeric dressings, considering the local and systemic treatment demands of chronic wounds.Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Competitive Factors Operational Program (POCI) for funding the projects POCI-01-0145-FEDER-028074 and UID/CTM/00264/201

    PRELIMINARY CHROMATOGRAPHICRESEARCH ON SOME SALVIA SPP. (LAMIACEAE)

    Get PDF
    Salvia genus, representative for the Lamiaceae family as it comprises approximately one thousand different species, is considered for a wide plethora of therapeutic actions, such as antioxidant, anti-inflammatory, hepatoprotective, antitumoral and antidiabetic activity. The paper presents the preliminary chromatographic investigations of the polyphenols in the aerial parts of some Salvia spp. Using high-performance thin-layer chromatography (HPTLC) coupled with photodensitometry, caffeic acid was identified and quantified in the 20% methanolic extracts of Salviaeherba, in descending order, as follows: S. nemorosa (3.096%) > S. verticillata (3.041%) > S. sclarea (2.663%) > S. glutinosa (1.962%) > S. aethiopis (0.926%)

    HISTO-ANATOMICAL AND CHROMATOGRAPHIC RESEARCHES ON CAMPANULA PERSICIFOLIA L. (CAMPANULACEAE) SPECIES

    Get PDF
    The paper presents the histo-anatomical researches on root, rhizome, aboveground stem and leaf of Campanula persicifolia L. (Campanulaceae) species, together with the thin-layer chromatography analysis of the polyphenols content of Campanulae persicifoliae herba. Chlorogenic acid (108.6 μg/mL) was identified in the 20% methanolic extract of the aerial parts

    Hydrodynamically Guided Hierarchical Self-Assembly of Peptide-Protein Bioinks

    Get PDF
    Effective integration of molecular self-assembly and additive manufacturing would provide a technological leap in bioprinting. This article reports on a biofabrication system based on the hydrodynamically guided co-assembly of peptide amphiphiles (PAs) with naturally occurring biomolecules and proteins to generate hierarchical constructs with tuneable molecular composition and structural control. The system takes advantage of droplet-on-demand (DoD) inkjet printing to exploit interfacial fluid forces and guide molecular self-assembly into aligned or disordered nanofibers, hydrogel structures of different geometries and sizes, surface topographies and higherordered constructs bound by molecular diffusion. PAs were designed to co-assemble during printing in cell diluent conditions with a range of extracellular matrix (ECM) proteins and biomolecules including fibronectin, collagen, keratin, elastin-like proteins (ELPs) and hyaluronic acid. Using combinations of these molecules, NIH-3T3 and adipose derived stem cells were bioprinted within complex structures while exhibiting high cell viability (> 88 %). By integrating self-assembly with 3D-bioprinting, the study introduces a novel biofabrication platform capable of encapsulating and spatially distributing multiple cell types within tuneable pericellular environments. In this way, the work demonstrates the potential of the approach to generate complex bioactive scaffolds for applications such as tissue engineering, in vitro models, and drug screening

    Organic residue analysis of Egyptian votive mummies and their research potential

    Get PDF
    YesVast numbers of votive mummies were produced in Egypt during the Late Pharaonic, Ptolemaic, and Roman periods. Although millions remain in situ, many were removed and have ultimately entered museum collections around the world. There they have often languished as uncomfortable reminders of antiquarian practices with little information available to enhance their value as artefacts worthy of conservation or display. A multi-disciplinary research project, based at the University of Manchester, is currently redressing these issues. One recent aspect of this work has been the characterization of natural products employed in the mummification of votive bundles. Using gas chromatography–mass spectrometry and the well-established biomarker approach, analysis of 24 samples from 17 mummy bundles has demonstrated the presence of oils/fats, natural waxes, petroleum products, resinous exudates, and essential oils. These results confirm the range of organic materials employed in embalming and augment our understanding of the treatment of votives. In this first systematic initiative of its kind, initial findings point to possible trends in body treatment practices in relation to chronology, geography, and changes in ideology which will be investigated as the study progresses. Detailed knowledge of the substances used on individual bundles has also served to enhance their value as display items and aid in their conservation.RCB is supported by a PhD studentship from the Art and Humanities Research Council (43019R00209). L.M. and S.A.W. are supported by a Leverhulme Trust Research Project Award (RPG-2013-143)

    Release of insulin from PLGA-alginate dressing stimulates regenerative healing of burn wounds in rats

    Get PDF
    Burn wound healing involves a complex set of overlapping processes in an environment conducive to ischemia, inflammation, and infection costing $7.5 billion/year in the US alone, in addition to the morbidity and mortality that occur when the burns are extensive. We previously showed that insulin, when topically applied to skin excision wounds, accelerates re-epithelialization, and stimulates angiogenesis. More recently, we developed an alginate sponge dressing (ASD) containing insulin encapsulated in PLGA microparticles that provides a sustained release of bioactive insulin for >20days in a moist and protective environment. We hypothesized that insulin-containing ASD accelerates burn healing and stimulates a more regenerative, less scarring, healing. Using a heat-induced burn injury in rats, we show that burns treated with dressings containing 0.04mg insulin/cm2, every three days for 9 days, have faster closure, faster rate of disintegration of dead tissue, and decreased oxidative stress.In addition, in insulin-treated wounds the pattern of neutrophil inflammatory response suggests faster clearing of the burn dead tissue. We also observe faster resolution of the pro-inflammatory macrophages. We also found that insulin stimulates collagen deposition and maturation with the fibers organized more like a basket weave (normal skin) than aligned and crosslinked (scar tissue). In summary , application of ASD-containing insulin-loaded PLGA particles on burns every three days stimulates faster and more regenerative healing. These results suggest insulin as a potential therapeutic agent in burn healing and, because of its long history of safe use in humans, insulin could become one of the treatments of choice when repair and regeneration are critical for proper tissue function.This work was supported by the National Natural Science Fund of China [grant numbers 81170761 and 81270909 (to Y.L.)]; the Natural Sciences and Engineering Research Council of Canada [grant numbers 204794-2011 (to M.H.) and private donor (to M.M.-G.)]
    corecore