2,245 research outputs found
Traditional Biocidal Replacement Viability of Microcrystalline Silver Chloride
The antimicrobial effects of silver ions and silver chloride nanoparticles have been well established while the efficacy of microcrystalline silver chloride has been less studied. Certex-AM, a microcrystalline silver chloride product produced by Cerion, Rochester, NY, was tested for its antimicrobial properties as a possible replacement for traditional biocidal techniques used in water cooling towers. The minimum inhibitory concentration (MIC) of the compound was determined using a microtiter broth assay. The compound was found to have inhibitory effects on bacterial growth for all tested organisms at concentrations greater than 9 ppm. Additional testing simulating a water cooling system showed the effectiveness of reducing an established wild population at concentrations of 10 ppm of the microcrystalline silver chloride. Certex-AM was found to be a promising replacement for traditional biocides as well as for other applications. Introduction of effective antimicrobial compounds such as this could reduce the pathogenic risk to humans associated with water cooling towers
Brecha digital en el sector educativo salvadoreño: retos y estrategias
El siguiente artículo presenta tres escenarios de análisis para auscultar la brecha digital en El Salvador: el teológico, el educativo y el educativo, tecnológico, precedidos por una reflexión sobre las TIC y la brecha digital; inicialmente, para concluir se proponen un conjunto de estrategias institucionales desarrolladas de índole tecnológico a modo de contrapeso de los grandes problemas de la brecha existent
Giordano Bruno contro l'abitudine a credere.
"Mi sono messo ancora una volta sulle orme del Nolano e ho scoperto altri sentieri di umanità intrecciata alla sua inquieta filosofia". Così il medico e filosofo napoletano Guido del Giudice parla del suo nuovo libro. L' Acrotismus, un neologismo bruniano che si riferisce alla summa della critica anti-aristotelica del Nolano, viene qui presentato nella sua prima traduzione integrale. Pubblicato a Wittenberg nel 1587, l'opera costituisce la riproposizione ampliata delle tesi discusse dal filosofo a Parigi due anni prima, nel corso di una tumultuosa disputa accademica tenutasi presso il College de Cambrai
Influence of the sebaceous gland density on the stratum corneum lipidome
The skin surface lipids (SSL) result from the blending of sebaceous and epidermal lipids, which derive from the sebaceous gland (SG) secretion and the permeability barrier of the stratum corneum (SC), respectively. In humans, the composition of the SSL is distinctive of the anatomical distribution of the SG. Thus, the abundance of sebum biomarkers is consistent with the density of the SG. Limited evidence on the influence that the SG exerts on the SC lipidome is available. We explored the differential amounts of sebaceous and epidermal lipids in areas at different SG density with lipidomics approaches. SC was sampled with adhesive patches from forearm, chest, and forehead of 10 healthy adults (8F, 2M) after mechanical removal of sebum with absorbing paper. Lipid extracts of SC were analysed by HPLC/(-)ESI-TOF-MS. In the untargeted approach, the naïve molecular features extraction algorithm was used to extract meaningful entities. Aligned and normalized data were evaluated by univariate and multivariate statistics. Quantitative analysis of free fatty acids (FFA) and cholesterol sulfate (CHS) was performed by targeted HPLC/(-)ESI-TOF-MS, whereas cholesterol and squalene were quantified by GC-MS. Untargeted approaches demonstrated that the relative abundance of numerous lipid species was distinctive of SC depending upon the different SG density. The discriminating species included FFA, CHS, and ceramides. Targeted analyses confirmed that sebaceous FFA and epidermal FFA were increased and decreased, respectively, in areas at high SG density. CHS and squalene, which are biomarkers of epidermal and sebaceous lipid matrices, respectively, were both significantly higher in areas at elevated SG density. Overall, results indicated that the SG secretion intervenes in shaping the lipid composition of the epidermal permeability barrier. © 2018, The Author(s)
Preferential Sampling of Elastic Chains in Turbulent Flows
A string of tracers, interacting elastically, in a turbulent flow is shown to
have a dramatically different behaviour when compared to the non-interacting
case. In particular, such an elastic chain shows strong preferential sampling
of the turbulent flow unlike the usual tracer limit: an elastic chain is
trapped in the vortical regions and not the straining ones. The degree of
preferential sampling and its dependence on the elasticity of the chain is
quantified via the Okubo-Weiss parameter. The effect of modifying the
deformability of the chain, via the number of links that form it, is also
examined.Comment: 6 pages, 4 figure
The frog skin-derived antimicrobial peptide esculentin-1a(1-21)nh2 promotes the migration of human hacat keratinocytes in an egf receptor-dependent manner: a novel promoter of human skin wound healing?
One of the many functions of skin is to protect the organism against a wide range of pathogens. Antimicrobial peptides (AMPs) produced by the skin epithelium provide an effective chemical shield against microbial pathogens. However, whereas antibacterial/antifungal activities of AMPs have been extensively characterized, much less is known regarding their wound healing-modulatory properties. By using an in vitro re-epithelialisation assay employing special cell-culture inserts, we detected that a derivative of the frog-skin AMP esculentin-1a, named esculentin-1a(1-21)NH2, significantly stimulates migration of immortalized human keratinocytes (HaCaT cells) over a wide range of peptide concentrations (0.025-4 μM), and this notably more efficiently than human cathelicidin (LL-37). This activity is preserved in primary human epidermal keratinocytes. By using appropriate inhibitors and an enzyme-linked immunosorbent assay we found that the peptide-induced cell migration involves activation of the epidermal growth factor receptor and STAT3 protein. These results suggest that esculentin-1a(1-21)NH2 now deserves to be tested in standard wound healing assays as a novel candidate promoter of skin re-epithelialisation. The established ability of esculentin-1a(1-21)NH2 to kill microbes without harming mammalian cells, namely its high anti-Pseudomonal activity, makes this AMP a particularly attractive candidate wound healing promoter, especially in the management of chronic, often Pseudomonas-infected, skin ulcers
EU-Japan: A Partnership of Renewed Importance. EU Centre Background, Brief 20th July 2018
This background brief explores the prospect of a stronger European Union’s (EU) economic and political leverage in the Asia Pacific region through the analysis of EU-Japan relations. The paper delves into the main drivers and implications of the two bilateral treaties recently concluded between the EU and Japan, the Economic Partnership Agreement (EPA) and Strategic Partnership Agreement (SPA). The political environment that surrounded the agreements is deeply marked by crisis and uncertainty. However, this paper develops the view that increased bilateral cooperation between the EU and Japan offers opportunities for the EU to boost its presence in Asia as well as increases both parties’ ability to face new challenges and adapt to a fast-changing international system
- …
