Effect of one and two stiffeners on residual stresses of ship hull

Failure of ship hulls may be a result of a combination of factors. Residual stress caused by welding of the stiffeners on to the steel plates is one of the contributing factors to the failure. This analysis was completed for a more in-depth look at the residual stress distribution found at a typical weld-stiffener connection of ship hulls. Three specimens were built to represent small segments of an actual ship hull. The sizing of the specimens was designed so they could be accommodated at the test facility available at the Canadian Neutron Beam Centre in the Chalk River Laboratories. The specimens were made out of 9.53 mm thick plate of 350 WT grade structural steel stiffened by L127x76.2x9.53 stiffeners. The non-destructive neutron diffraction method was used to collect strain data at locations within the volume of the specimens. The method of neutron diffraction uses the crystal lattice of the sample material as an internal strain gauge. The test results were analyzed to determine the distribution of the residual stress in the parent steel plate and the effect the welding of the stiffeners has on the residual stress field. This thesis presents the three-dimensional residual stress for the parent plate and specimens with one and two stiffeners obtained from this study

The patterns for glycogen utilization during work overload in the isolated perfused rat heart.

Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1977 .K366. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.H.K.)--University of Windsor (Canada), 1977

Assessing Internal Audit Practice: A Case of Selectedbureaus in Snnprs

Internal audit plays a significant role in safeguarding and effective utilization of public resources. This study was conducted to assess the practice of internal audit: A case study of selected bureaus in SNNPRS. The researcher employed descriptive research design. Both simple random and purposive sampling techniques were employed by researcher in order to select 195 professionals in the bureaus. The data collected via structured questionnaire has been analyzed by statistical software, SPSS version 21.0. Accordingly, the result of descriptive statistics showed that, independence and objectivity and quality of internal audit has positive contribution to internal audit practice. The study also found that the major challenges of internal audit in regional sector bureaus are lack of training, sufficient audit facilities, management support, competent audit staff, adequate man power and presence of interference by the higher officials.  Based on the findings of the study, the researcher forwarded possible recommendations for bureaus to work on identified results due to fact that they can be taken in to considerations have positive influence in improving internal audit practice of bureaus.

Helsingørs søhandel, dens storhed og dens endeligt

Arkivaren ved Helsingør Bymuseum følger her Henning Henningsens arbejde om Øresundstolden op med en artikel, der viser, at Sundtoldens ophævelse i 1857 ikke betød den bratte nedgang for byen og havnen, som man i almindelighed forestiller si

Distributions of Welding-Induced Residual Stresses in Steel Plate Structures

One of the leading factors of early failure in welded steel structures is caused by the presence of residual stresses. These stresses are caused by the welding process and they can be as high as the yield stress of the material. The residual stresses along with the other service loads experienced by a structure can lead to premature failures. This study was completed to obtain a full understanding of the residual strains and stresses found in various steel plated welded structures. Several factors affecting the welding process were examined such as the welding heat input, the stiffener spacing, the thickness of the parent plate, the termination of a stiffener, and interruption duration during the welding process. The specimens were tested using two test methods. Nine specimens were built and tested and these data were then combined with test data of three specimens tested earlier. Three specimens were tested using the X-Ray diffraction method. Two of the specimens were also simulated using finite element method by using ANSYS. The test results from all three methods of residual stress collection were compared and analyzed. This dissertation presents the residual stress distributions found for all twelve specimens and examines the effects of the various welding factors on the residual stress patterns

Accurate interaction energies at DFT level by means of an efficient dispersion correction

This paper presents an approach for obtaining accurate interaction energies at the DFT level for systems where dispersion interactions are important. This approach combines Becke and Johnson's [J. Chem. Phys. 127, 154108 (2007)] method for the evaluation of dispersion energy corrections and a Hirshfeld method for partitioning of molecular polarizability tensors into atomic contributions. Due to the availability of atomic polarizability tensors, the method is extended to incorporate anisotropic contributions, which prove to be important for complexes of lower symmetry. The method is validated for a set of eighteen complexes, for which interaction energies were obtained with the B3LYP, PBE and TPSS functionals combined with the aug-cc-pVTZ basis set and compared with the values obtained at CCSD(T) level extrapolated to a complete basis set limit. It is shown that very good quality interaction energies can be obtained by the proposed method for each of the examined functionals, the overall performance of the TPSS functional being the best, which with a slope of 1.00 in the linear regression equation and a constant term of only 0.1 kcal/mol allows to obtain accurate interaction energies without any need of a damping function for complexes close to their exact equilibrium geometry

A Purified Capsular Polysaccharide Markedly Inhibits Inflammatory Response during Endotoxic Shock

Capsular material of the opportunistic fungus Cryptococcus neoformans is mainly composed of a polysaccharide named glucuronoxylomannan (GXM). In this study, the effects of GXM were analyzed in an in vivo experimental system of LPS-induced shock. Endotoxic shock was induced in mice by a single intraperitoneal injection of LPS from Escherichia coli. GXM treatment reduced the mortality of mice at early stages. Mice treated with LPS alone showed markedly increased plasma levels of TNF-α, IL-1β, and IL-6, whereas mice treated with GXM too showed significantly lower plasma levels of these cytokines. This effect was related to a marked suppression of Akt and IkBα activation. Importantly, the inhibitory effect of GXM on pro-inflammatory cytokine secretion was reproduced by treatment with Wortmannin, an inhibitor of the Akt transcription pathway. Our results indicate that GXM has a beneficial effect on endotoxic shock, resulting in a significant increase in rate of survival by dampening the hyper-inflammatory response

An Untargeted Metabolomic Analysis of Lacticaseibacillus (L.) rhamnosus, Lactobacillus (L.) acidophilus, Lactiplantibacillus (L.) plantarum and Limosilactobacillus (L.) reuteri Reveals an Upregulated Production of Inosine from L. rhamnosus

Lactic acid bacteria are considered an inexhaustible source of bioactive compounds; indeed, products from their metabolism are known to have immunomodulatory and anti-inflammatory activity. Recently, we demonstrated that Cell-Free Supernatants (CFS) obtained from Lactobacillus (L.) acidophilus, Lactiplantibacillus (L.) plantarum, Lacticaseibacillus (L.) rhamnosus, and Limosilactobacillus (L.) reuteri can impair Candida pathogenic potential in an in vitro model of epithelial vaginal infection. This effect could be ascribed to a direct effect of living lactic acid bacteria on Candida virulence and to the production of metabolites that are able to impair fungal virulence. In the present work, stemming from these data, we deepened our knowledge of CFS from these four lactic acid bacteria by performing a metabolomic analysis to better characterize their composition. By using an untargeted metabolomic approach, we detected consistent differences in the metabolites produced by these four different lactic acid bacteria. Interestingly, L. rhamnosus and L. acidophilus showed the most peculiar metabolic profiles. Specifically, after a hierarchical clustering analysis, L. rhamnosus and L. acidophilus showed specific areas of significantly overexpressed metabolites that strongly differed from the same areas in other lactic acid bacteria. From the overexpressed compounds in these areas, inosine from L. rhamnosus returned with the best identification profile. This molecule has been described as having antioxidant, anti-inflammatory, anti-infective, and neuroprotective properties. The biological significance of its overproduction by L. rhamnosus might be important in its probiotic and/or postbiotic activity

Fungal burden, dimorphic transition and candidalysin: Role in Candida albicans-induced vaginal cell damage and mitochondrial activation in vitro

Candida albicans (C. albicans) can behave as a commensal yeast colonizing the vaginal mucosa, and in this condition is tolerated by the epithelium. When the epithelial tolerance breaks down, due to C. albicans overgrowth and hyphae formation, the generated inflammatory response and cell damage lead to vulvovaginal candidiasis (VVC) symptoms. Here, we focused on the induction of mitochondrial reactive oxygen species (mtROS) in vaginal epithelial cells after C. albicans infection and the involvement of fungal burden, morphogenesis and candidalysin (CL) production in such induction. Bioluminescent (BLI) C. albicans, C. albicans PCA-2 and C. albicans 529L strains were employed in an in vitro infection model including reconstituted vaginal epithelium cells (RVE), produced starting from A-431 cell line. The production of mtROS was kinetically measured by using MitoSOXTM Red probe. The potency of C. albicans to induced cell damage to RVE and C. albicans proliferation have also been evaluated. C. albicans induces a rapid mtROS release from vaginal epithelial cells, in parallel with an increase of the fungal load and hyphal formation. Under the same experimental conditions, the 529L C. albicans strain, known to be defective in CL production, induced a minor mtROS release showing the key role of CL in causing epithelial mithocondrial activation. C. albicans PCA-2, unable to form hyphae, induced comparable but slower mtROS production as compared to BLI C. albicans yeasts. By reducing mtROS through a ROS scavenger, an increased fungal burden was observed during RVE infection but not in fungal cultures grown on abiotic surface. Collectively, we conclude that CL, more than fungal load and hyphae formation, seems to play a key role in the rapid activation of mtROS by epithelial cells and in the induction of cell-damage and that mtROS are key elements in the vaginal epithelial cells response to C. albicans

A study of educational leadership preparation concerning the assistant principal : perspectives of Missouri principals and assistant principals

Abstract from short.pdf file.Dissertation supervisor: Dr. Cynthia MacGregor.Includes vita.It is unclear if the initial preparation of educational leaders, in relation to the role of assistant principals (APs), has kept pace with growing demands associated with the position. Little research exists specifically addressing the initial developmental preparation of APs. Elements of a needs assessment and program evaluation combine to build infrastructure for a conceptual framework to guide this study. A mixed method design for this study was determined to be the best method in which to provide answers concerning the proposed research questions. Participants consisted of lead and assistant principals from school districts across Missouri. Quantitative and qualitative data was analyzed for trends. Quantitative and qualitative data was compared to one another in order to attain a thorough and comprehensive examination of collected data.Includes bibliographical references (pages 149-161)