Modern Teaching and Training in Metallurgical Engineering

This contribution deals with advanced educational technologies needed to equip customers from higher education institutions, research and industry with efficient tools supporting their work and operating new skills‐training methods. The challenges are reducing the training costs, improving quality and increasing the number of graduates in engineering departments. The concept of a Virtual Lab based on the combination of various teaching methods and tools is presented. Principles of mathematisation in metallurgical education and training are discussed. An example of online course designed in the form of Virtual Lab is demonstrated.     

A new high-order accurate continuous Galerkin method for linear elastodynamics problems

A new high-order accurate time-continuous Galerkin (TCG) method for elastodynamics is suggested. The accuracy of the new implicit TCG method is increased by a factor of two in comparison to that of the standard TCG method and is one order higher than the accuracy of the standard time-discontinuous Galerkin (TDG) method at the same number of degrees of freedom. The new method is unconditionally stable and has controllable numerical dissipation at high frequencies. An iterative predictor/multi-corrector solver that includes the factorization of the effective mass matrix of the same dimension as that of the mass matrix for the second-order methods is developed for the new TCG method. A new strategy combining numerical methods with small and large numerical dissipation is developed for elastodynamics. Simple numerical tests show a significant reduction in the computation time (by 5–25 times) for the new TCG method in comparison to that for second-order methods, and the suppression of spurious high-frequency oscillations.     

United States Nuclear Regulatory Commission Research Program on molten core debris interactions in the reactor cavity

The NRC's Research Program on Core-Debris/Cavity Interactions comprises two principal elements: (1) an analytical effort focused primarily on development of computer codes needed to predict the potential consequences of risk-significant severe-accident scenarios; and (2) an experimental component to provide insights into the relevant phenomenological processes and to develop the experimental data base necessary for validation of the codes. The analytical activities at Sandia National Laboratories (SNL) focus primarily on refinement and validation of the CORCON and VANESA codes. Two major experimental activities are also based at SNL: (1) the large-scale SURC tests address the thermal-hydraulic phenomena in the cavity as well as aerosol release associated with prototypical core-melt materials in various types of concrete crucibles, while (2) the WITCH and GHOST experiments are concerned with aerosol generation and radionuclide release phenomena. A program of small-scale special-effects tests at Brookhaven National Laboratory (BNL) is coupled to a concomitant model-development and code-validation activity. In addition, measurements are being made at Battelle Columbus Laboratory (BCL) to augment the thermochemical data base needed in the VANESA code to permit refined radiological source-term predictions. The current scope and status of this research is reviewed.     

Granulocyte colony-stimulating factor worsens the outcome of experimental Klebsiella pneumoniae pneumonia through direct interaction with the bacteria

Besides its well-established effects on granulocytopoiesis, granulocyte colony-stimulating factor (G-CSF) has been shown to have direct effects on the recruitment and bactericidal ability of neutrophils, resulting in improved survival of experimentally infected animals. We studied the effect of G-CSF on the course of experimental pneumonia induced by Klebsiella pneumoniae, an important gram-negative bacillary pulmonary pathogen. Using a highly reproducible murine model, we here show the paradoxical finding that mortality from infection was significantly increased when animals received G-CSF before induction of pneumonia. Administration of G-CSF promoted replication of bacteria in the liver and spleen, thus indicating an impairment rather than an enhancement of antibacterial mechanisms. By contrast, a monoclonal antibody against Klebsiella K2 capsule significantly reduced bacterial multiplication in the lung, liver, and spleen, and abrogated the increased mortality caused by G-CSF. In vitro studies showed a direct effect of G-CSF on K pneumoniae resulting in increased capsular polysaccharide (CPS) production. When bacteria were coincubated with therapeutically achievable concentrations of G-CSF, phagocytic uptake and killing by neutrophils was impaired. Western blot analysis showed three binding sites of G-CSF to K pneumoniae. Binding of 125I-G-CSF to K pneumoniae was displaced by an excess of unlabeled G-CSF, whereas an unrelated cytokine, interleukin-1alpha, did not compete with G-CSF binding to the bacteria. Thus, in this model, the direct effect of G-CSF on a bacterial virulence factor, CPS production, outweighed any beneficial effect of G-CSF on recruitment and stimulation of leukocytes.     

Limb salvage surgery for widely infiltrating bony sarcomas

OBJECTIVE: To determine whether neoadjuvant chemotherapy and radiotherapy for bony sarcomas extending into soft tissues would allow limb salvage yet maintain local disease control. DESIGN: A prospective cohort study. SETTING: A university-affiliated cancer centre in Alberta. PATIENTS: All patients with potentially curable, widely infiltrating bony sarcomas of the extremity without neurologic deficit, referred to the centre in the 6 years from January 1984 to December 1990. There were 11 patients; 1 did not complete the protocol. The mean follow-up was 24 months. INTERVENTIONS: Adriamycin (doxorubicin) was infused for 3 days at a rate of 30 mg/d. A few days later radiotherapy was given 5 days a week for 10 doses at a rate of 3.0 Gy per dose. Four to 5 weeks later the tumour was excised surgically, with placement of a bone allograft or prosthesis, allowing a 1-cm margin of healthy soft tissue and a 5-cm margin of healthy bone and marrow cavity whenever possible. MAIN OUTCOME MEASURES: Need for limb amputation, infectious complications, recurrence of local or regional disease. RESULTS: One patient underwent amputation after fracture through the tumour site. There were two postoperative infections, one acute and one chronic. All patients had full neurologic function of the distal limb. There was no local or regional recurrence of disease. CONCLUSION: Neoadjuvant chemotherapy followed by radiotherapy and tumour excision provides control of aggressive local bone sarcomas while maintaining limb integrity.     

Perspective:Societally connected multimedia across cultures

The advance of the Internet in the past decade has radically changed the way people communicate and col- laborate with each other. Physical distance is no more a barrier in online social networks, but cultural differences (at the individual, community, as well as societal levels) still govern human-human interactions and must be con- sidered and leveraged in the online world. The rapid de-ployment of high-speed Internet allows humans to interact using a rich set of multimedia data such as texts, pictures, and videos. This position paper proposes to define a new research area called ’connected multimedia’, which is the study of a collection of research issues of the super-area social media that receive little attention in the literature. By connected multimedia, we mean the study of the social and technical interactions among users, multimedia data, and devices across cultures and explicitly exploiting the cultural differences. We justify why it is necessary to bring attention to this new research area and what benefits of this new research area may bring to the broader scientific research community and the humanity.     

Psychrotrophic violacein-producing bacteria isolated from Lake Winnipeg,Canada

Violet and purple bacterial pigmentations are uncommon when considering strict aerobes. Here we report discovery of two novel isolates, P102 and P117 from the freshwater Lake Winnipeg, each with violet to deep purple colony colouration. The relationship between pigment production and growth was investigated under different conditions, including a variety of carbon sources, pH, and temperatures. The violet compounds were purified using polar organic solvents, and then structurally characterized via mass spectrometry and nuclear magnetic resonance to be violacein and deoxyviolacein. Strain P117 produced higher concentrations of the darker pigment deoxyviolacein, which resulted in a deeper hue of violet than in cultures of P102. Strain P102, synthesized violacein maximally in liquid rich organic medium at pH 8 and 20 °C, and had 99.3% sequence similarity to the 16S rDNA from Janthinobacterium lividum. Strain P117, related to Massilia violaceinigra sharing 99.2% 16S rDNA sequence similarity, also produced violacein at similar optimal conditions, but developed higher concentrations of pigment at 15 °C. Culture-based methods found that violacein producers composed 0.001% or 0.023% CFU of environmental heterotrophic populations using BG-11 and potato-based media, respectively. Culture-independent high-throughput ribosomal 16S V4 sequencing of environmental DNA was used to detect Gram-negative species known for their production of violacein. Of all bacterial and archaeal sequences present during the fall in littoral waters and sediment of Lake Winnipeg, 5.5% and 6.3%, respectively, belonged to species that have similar pigment, demonstrating the scarcity of violacein producers in this aquatic freshwater system.     

Evidence of successful river spawning by lake trout (Salvelinus namaycush) in the Lower Niagara River,Lake Ontario

Restoration of a wild-produced lake trout Salvelinus namaycush population in Lake Ontario has not been successful despite the adult population often meeting or exceeding restoration targets. Lack of high-quality spawning habitat in Lake Ontario is suggested as one impediment to recruitment of wild lake trout, although the quantity and location of spawning habitat is poorly understood. If high-quality spawning habitat is limited in Lake Ontario, lake trout may be using uncommon spawning locations such as rivers. Anecdotal angler accounts point to the Niagara River as a lake trout spawning location. To better understand the potential of the Niagara River as a spawning location, egg and juvenile fish collections were conducted 12–14 river kilometers from the mouth of the Niagara River from 2010 to 2012; and mature female lake trout with surgically implanted acoustic tags were monitored from 2015 to 2019. Genetic analyses confirmed 60% of collected eggs and 93% of collected post-hatch juvenile fish in the Niagara River were lake trout. Tagged female lake trout returned to the Niagara River over consecutive years during the spawning season. The short duration of lake trout presence in the river (mean = 56 days/year) suggests female lake trout use the Niagara River primarily for spawning. Diversity in spawning locations may provide lake trout population’s resilience against environmental variability through a portfolio effect. Improved identification of riverine spawning locations, including their overall contribution to wild recruitment, may be a useful tool for managers to restore a wild-produced population of lake trout in Lake Ontario.