34 research outputs found
Acoustic Identification of Liquefaction Potential
The interparticle arrangement, or fabric, of sands is a key determinant of sample rigidity. This rigidity, in large part, determines the velocity and attenuation of acoustic transmissions in a test specimen, as well as its resistance to liquefaction. Utilizing high frequency small-amplitude compressional wave transmissions, different fabric arrangements of standard triaxial samples of the same sand have been reliably identified from their acoustic response. Both the compressional wave velocity and attenuation were used to determine the acoustic signature of a sample. Cyclic triaxial testing of the same laboratory-prepared samples revealed that there is direct relationship between the acoustic response of a sample prepared by a particular method and its resistance to liquefaction. The effect of stress history, induced by pre-shaking, on the resistance to liquefaction of a test sample was also detected by changes in the acoustic signature
Monitoring of trace metals, biochemical composition and growth of Axillary seabream (Pagellus acarne Risso, 1827) in offshore Copper alloy net cage
The study was conducted to assess trace metal contents, biochemical composition and growth performance of axillary seabream (Pagellus acarne Risso, 1827) cultured in a copper alloy mesh cage. A total of 400 axillary seabream (initial mean weight: 176.0±14.0 g), a new candidate species for the Mediterranean aquaculture, were stocked into a high-density polyethylene frame gravity cage and fed a commercial seabream diet for a period of 6 months. At the end of the feeding trial, fish reached a final weight of 264.8±16.8 g with a weight increase of 88.8 g and a feed conversion rate of 2.51. Overall, relative growth rate, specific growth rate and feed conversion ratio were satisfactory and comparable to the pelagic fishes such as gilthead seabream or European seabass, which are presently the main fish species for the Mediterranean aquaculture industry. Trace elements in fish grown in copper alloy net cages over a 6-month period showed satisfactory results, as the metal concentrations in fish tissues such as liver, skin, muscle and gills were below the reported upper limits for human consumption, indicating that copper alloy net is an acceptable and safe material for finfish cage aquaculture. Furthermore, from the growth performance data obtained in the present study, it can be concluded that axillary seabream showed potential for cage farming, and thus is a promising new candidate for the Mediterranean aquaculture industry
Metabolomic and high-throughput sequencing analysis—modern approach for the assessment of biodeterioration of materials from historic buildings
Preservation of cultural heritage is of paramount importance worldwide. Microbial colonization of construction materials, such as wood, brick, mortar and stone in historic buildings can lead to severe deterioration. The aim of the present study was to give modern insight into the phylogenetic diversity and activated metabolic pathways of microbial communities colonized historic objects located in the former Auschwitz II-Birkenau concentration and extermination camp in Oświęcim, Poland. For this purpose we combined molecular, microscopic and chemical methods. Selected specimens were examined using Field Emission Scanning Electron Microscopy (FESEM), metabolomic analysis and high-throughput Illumina sequencing. FESEM imaging revealed the presence of complex microbial communities comprising diatoms, fungi and bacteria, mainly cyanobacteria and actinobacteria, on sample surfaces. Microbial diversity of brick specimens appeared higher than that of the wood and was dominated by algae and cyanobacteria, while wood was mainly colonized by fungi. DNA sequences documented the presence of 15 bacterial phyla representing 99 genera including Halomonas, Halorhodospira, Salinisphaera, Salinibacterium, Rubrobacter, Streptomyces, Arthrobacter and 9 fungal classes represented by 113 genera including Cladosporium, Acremonium, Alternaria, Engyodontium, Penicillium, Rhizopus and Aureobasidium. Most of the identified sequences were characteristic of organisms implicated in deterioration of wood and brick. Metabolomic data indicated the activation of numerous metabolic pathways, including those regulating the production of primary and secondary metabolites, for example, metabolites associated with the production of antibiotics, organic acids and deterioration of organic compounds. The study demonstrated that a combination of electron microscopy imaging with metabolomic and genomic techniques allows to link the phylogenetic information and metabolic profiles of microbial communities and to shed new light on biodeterioration processes
Au coated Ni nanowires with tuneable dimensions for biomedical applications
Due to their shape anisotropy, high aspect ratio magnetic nanoparticles offer many advantages in biomedical applications. For biocompatibility, it is essential to have full control over the dimensions and surface chemistry of the particles. The aim of this study was to synthesize biocompatible nanowires with tuneable dimensions. This was achieved by electrodeposition of Ni in polycarbonate membranes. To ensure biocompatibility, a continuous gold coating was deposited onto the Ni wires by a newly developed electroless deposition method. The coating was analysed using electron microscopy and X-ray diffraction. Magnetic properties, anisotropy and Au film thickness were studied using vibrating sample magnetometry. After biofunctionalization, no significant cytotoxic effects were found in studies involving a diverse range of primary and tumour cells exposed to increasing concentrations of nanowires for up to 7 days. These nanowires may thus be used for in vivo applications such as magnetic drug deliver
Cultural variations in the relationship between anger coping styles, depression and life satisfaction
Hypotheses are tested that ways of handling anger and their consequences will differ in student samples drawn from dignity cultures (UK and Finland), honor cultures (Turkey and Pakistan) and face cultures (Hong Kong and China). In line with our hypotheses, holding anger in and controlling anger correlate positively in face cultures but not in other samples, whereas holding anger in and letting anger out correlate positively in honor cultures but not in other samples. Furthermore, holding anger in and letting anger out are more strongly predictive of high depression and low life satisfaction in honor cultures than in other samples. The results provide support for the cross-cultural validity of Spielberger's (1999) anger expression inventory and for the proposition that differences in ways of handling anger can be understood in terms of contrasting cultural contexts
Biophysical Characterization of CD6—TCR/CD3 Interplay in T Cells
Activation of the T cell receptor (TCR) on the T cell through ligation with antigen-MHC complex of an antigen-presenting cell (APC) is an essential process in the activation of T cells and induction of the subsequent adaptive immune response. Upon activation, the TCR, together with its associated co-receptor CD3 complex, assembles in signaling microclusters that are transported to the center of the organizational structure at the T cell-APC interface termed the immunological synapse (IS). During IS formation, local cell surface receptors and associated intracellular molecules are reorganized, ultimately creating the typical bull's eye-shaped pattern of the IS. CD6 is a surface glycoprotein receptor, which has been previously shown to associate with CD3 and co-localize to the center of the IS in static conditions or stable T cell-APC contacts. In this study, we report the use of different experimental set-ups analyzed with microscopy techniques to study the dynamics and stability of CD6-TCR/CD3 interaction dynamics and stability during IS formation in more detail. We exploited antibody spots, created with microcontact printing, and antibody-coated beads, and could demonstrate that CD6 and the TCR/CD3 complex co-localize and are recruited into a stimulatory cluster on the cell surface of T cells. Furthermore, we demonstrate, for the first time, that CD6 forms microclusters co-localizing with TCR/CD3 microclusters during IS formation on supported lipid bilayers. These co-localizing CD6 and TCR/CD3 microclusters are both radially transported toward the center of the IS formed in T cells, in an actin polymerization-dependent manner. Overall, our findings further substantiate the role of CD6 during IS formation and provide novel insight into the dynamic properties of this CD6-TCR/CD3 complex interplay. From a methodological point of view, the biophysical approaches used to characterize these receptors are complementary and amenable for investigation of the dynamic interactions of other membrane receptors
Nation-level moderators of the extent to which self-efficacy and relationship harmony predict students’ depression and life satisfaction: evidence from ten cultures
Previous two-nation comparisons have provided evidence that self-efficacy may be a protective factor against depression in individualist cultures, whereas relationship harmony may be a stronger protective factor in collectivist cultures. However, wider sampling and more specific measures of cultural difference are required to test these conclusions. Student ratings of depression and life satisfaction were surveyed in 10 samples drawn from nine nations. Culture-level individualism positively moderated the relationship of self-efficacy to low depression. However, culture-level collectivism negatively moderated the linkage of relationship harmony to depression. To better understand these effects, four separate nation-level predictors derived from dimensions of self-construal were employed. Effects of self-efficacy were strongest where cultural models of selfhood emphasized self-direction (vs. receptiveness to influence); effects of relationship harmony were strongest where cultural models of selfhood emphasized dependence on others (vs. self-reliance). These results illustrate the value of unpackaging the diffusely defined concept of individualism-collectivism
Method to calculate the fire resistance of circular reinforced concrete columns
In response to the growing need for an interest in the economic assessment of building-code provisions, the Institute for Research in Construction (IRC) of the National Research Council of Canada (NRCC) is developing analytical tools that should be of interest to design professionals. One such development is aPC-based model that can be used to assess the cost effectiveness of fire-safety provisions in buildings. At this stage, the risk-cost assessment model applies only to Canadian apartment buildings, but NRCC has a longer-term program to develop similar models for other types of buildings.En r\ue9ponse au besoin et \ue0 l?int\ue9r\ueat de plus en plus marqu\ue9s relativement \ue0 l?\ue9valuation \ue9conomique des dispositions du code du b\ue2timent, l?Institut de recherche en construction (IRC) du Conseil national de recherches du Canada (CNRC) d\ue9veloppe actuellement des outils d?analyse qui devraient int\ue9resser les professionnels du domaine de la conception. L?un de ces nouveaux d\ue9veloppements est celui d?un mod\ue8le sur ordinateur qui peut \ueatre utilis\ue9 pour \ue9valuer l?efficacit\ue9 par rapport au co\ufbt des dispositions de s\ue9curit\ue9 incendie dans les b\ue2timents. \uc0 ce stade-ci, le mod\ue8le d?\ue9valuation du co\ufbt par rapport au risque s?applique seulement aux immeubles d?appartements canadiens, mais le CNRC a mis en place un programme \ue0 plus long terme visant \ue0 mettre au point des mod\ue8les semblables pour d?autres types de b\ue2timents.Peer reviewed: YesNRC publication: Ye