Analysis of Material Flow in Screw Extrusion of Aluminum

Bjørn Haugen,Magnus Ørnskar,Torgeir Welo,Fredrik Widerøe 한국소성가공학회 2010 기타자료 Vol.2010 No.6

Screw extrusion of aluminum is a new process for production of aluminum profiles. The commercial potential could be large. Little experimental and numerical work has been done with respect to this process. The material flow of hot aluminum in a screw extruder has been analyzed using finite element formulations for the non-Newtonian Navier-Stokes equations. Aluminum material properties are modeled using the Zener-Holloman material model. Effects of stick-slip conditions are investigated with respect to pressure build up and mixing quality of the extrusion process. The numerical results are compared with physical experiments using an experimental screw extruder.

Training, mental preparation and unmediated practice among soccer referees: An analysis of elite and sub-elite referees` reported practice

( Rune Giske ),( Tommy Haugen ),( Bjørn Tore Johansen ) 한국스포츠정책과학원(구 한국스포츠개발원) 2016 International Journal of Applied Sports Sciences Vol.28 No.1

It has been suggested that highly motivated and passionate referees are more inclined to pursue higher league levels and, thereby, invest more hours in performance preparations and more general soccer activity. However, limited knowledge is available about practice and mental preparation among elite soccer referees. Our study aim was to investigate referees’ practice and involvement in unmediated soccer activity. We further sought to examine possible preparation differences between elite and sub-elite referees. Comparing elite with sub-elite referees practice may reveal underlying performance principles that may form a basis for trainings methods facilitating referee performance. The following hypotheses were tested: a) elite referees will report higher frequency of physical and mental training compared with sub-elite referees and b) elite referees will report higher involvement in unmediated relevant soccer activity compared with sub-elite referees. Among the 98 top-class referees in Norway, 83 (84.7% response rate, 73 men and ten women, aged 20.46 years) completed a survey about their training volume and content, mental training and involvement in unmediated soccer activity. Reported training volume and content are consistent with referees’ physical demands. Elite referees report significantly greater use of mental training compared with sub-elite referees, while there were no group differences on physical training volume and content or unmediated soccer activity. The results confirm only one of the hypotheses and support the assumption that mental training requires more motivation than physical training even though the latter has quantifiable results that are more regularly measured.

Preclinical Models of Follicular Cell-Derived Thyroid Cancer: An Overview from Cancer Cell Lines to Mouse Models

전민지,Bryan R. Haugen 대한내분비학회 2022 Endocrinology and metabolism Vol.37 No.6

The overall prognosis of thyroid cancer is excellent, but some patients have grossly invasive disease and distant metastases with limited responses to systemic therapies. Thus, relevant preclinical models are needed to investigate thyroid cancer biology and novel treatments. Different preclinical models have recently emerged with advances in thyroid cancer genetics, mouse modeling and newcell lines. Choosing the appropriate model according to the research question is crucial to studying thyroid cancer. This review will discuss the current preclinical models frequently used in thyroid cancer research, from cell lines to mouse models, and future perspectives on patient-derived and humanized preclinical models in this field.

Role Conflict of Chinese Student-Athletes: Distinct Challenges They Face and Implications for Collegiate Sport Administrators

Jules Woolf,Guangzhou Chen,Matt Haugen,Jon Welty Peachey 글로벌지식마케팅경영학회 2024 Journal of Global Sport Management Vol.9 No.1

The number of Chinese student-athletes (CSAs) at National Collegiate Athletic Association (NCAA) schools in the United States has increased dramatically in recent years. However, little is known about the distinct challenges CSAs face as they adopt the role of student and athlete, and the potential for role conflict to occur. This study explored the ways in which CSAs experienced role conflict and how they managed this conflict. Ten interviews were conducted with current or former CSAs at NCAA Division I schools. Findings revealed that CSAs experienced role conflict due to con-trasting expectations from different stakeholders, the lack of aca-demic preparedness, and unfamiliarity with the collegiate sport system. Meanwhile, CSAs managed their role conflict by realigning role expectations and shifting role identity. The findings demon-strate how role conflict can be applied to a cross-cultural context, while informing collegiate sport administrators of efforts to man-age CSAs transition into the NCAA system.

High Production of Recombinant Norwegian Salmonid Alphavirus E1 and E2 Proteins in Escherichia coli by Fusion to Secretion Signal Sequences and Removal of Hydrophobic Domains

Anne Tondervik,Simone Balzer,Tone Haugen,Håvard Sletta,Marit Rode,Karine Lindmo,Trond E. Ellingsen,Trygve Brautaset 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.4

The Norwegian salmonid alphavirus (NSAV)infects farmed Atlantic salmon and rainbow trout, causes pancreas disease and leads to economic losses and fish health issues for the aquaculture. Vaccines are available,but recurring infection outbreaks at Norwegian fish farms have led to endeavours in finding solutions for increased prevention. The NSAV E1 and E2 envelope proteins are potential targets for production of recombinant subunit vaccines and for generation of antibodies for diagnostics. Efficient expression of target proteins is necessary for these applications, and here we present a new strategy for expressing this kinds of viral proteins. We show that 5'-terminal fusion of signal sequences OmpA and CSP to the e1 and e2 genes and removal of the C-terminal hydrophobic interaction and transmembrane domains of E1 and E2 leads to significantly increased expression levels. Recombinant Escherichia coli strains for high-level production of E1 and E2 harbouring these modifications were established using the inducible XylS/Pm expression cassette. Furthermore,reduction of temperature to 16oC after induction leads to 4-fold increase in production for E1, and under high-celldensity cultivations we obtained production levels up to 2.3 g/L. We also show that these proteins can be purified from inclusion bodies by affinity chromatography. This demonstrates the present approach as promising for large scale production of such viral proteins.

Comparison of young male mice of two different strains (C57BL/6J and the hybrid B6129SF1/J) in selected behavior tests: a small scale study

Kristine Eraker Aasland Hansen,Alexandra M. Hudecová,Fred Haugen,Eystein Skjerve,Erik Ropstad,Karin E. Zimmer 한국실험동물학회 2022 Laboratory Animal Research Vol.38 No.4

Background: All mouse strains are different, before choosing a strain for a large study, a small scale study should be done. In this study, we compared young males of two mouse strains, C57BL/6J and the hybrid B6129SF1/J, and gained knowledge on their performance in three different behavioral tests; open field (OF) test, Barnes maze (BM) test and a restraint stress test. Results: We found that the young males of the C57BL/6J strain spent more time moving in the OF. In the BM, the hybrid covered less ground before reaching the goal box during the first three sessions, than the C57BL/6J. The hybrid left more fecal pellets than C57BL/6J both in OF and BM. During the stress test, the C57BL/6J had a lower corticosterone response than the hybrid. Conclusions: Our findings indicate that the C57BL/6J has a presumably higher locomotor activity and/or explorative behavior than the hybrid, while the hybrid appeared more sensitive to stress.

The Relationship Between Efficacy and Burnout in Coaches

Sandra E. Short,Martin W. Short,Chris R. Haugen 한국코칭능력개발원 2015 International Journal of Coaching Science Vol.9 No.1

This study examined the relationship between coaching efficacy and coaching burnout. Based on previous theory and research in these areas, it was hypothesized that coaches who were higher in coaching efficacy would experience less burnout during a competitive season compared to those lower in coaching efficacy. The sample was comprised of high school basketball head coaches. For the pre-season, 101 coaches participated, however only 68 of them followed through by completing the post-season measures. Coaching efficacy was measured with the Coaching Efficacy Scale (Feltz, Chase, Moritz, & Sullivan, 1999). Coaching burnout was assessed using a modified version of Raedeke’s (1997) athlete burnout measure. Descriptive results showed that coaches had lower coaching efficacy and higher coaching burnout scores at post-season compared to pre-season. Correlations between coaching efficacy and burnout were negative at both time periods. Differences in coaching burnout were examined using a 2 (high / low coaching efficacy group) by 2 (pre-post season) MANOVA with repeated measures on the last factor. There were several significant main effects and interactions, and in general, as time passed the low efficacy coaches were more burned out compared to the high efficacy coaches. The results imply that a high sense in one’s coaching efficacy may have an insulating effect against the large number of stressors that have been associated with the coaching profession.

On the External Effects Affecting Torsional Modes in Guide Vanes

Petter T K Østby,Eivind Myrvold,Jan Tore Billdal,Bjørnn Haugen 한국유체기계학회 2019 International journal of fluid machinery and syste Vol.12 No.2

Rotor stator interaction in high-head Francis turbines has led to several failures in recent years. Increasing efficiency demands require design optimization of the turbine components, which may lead to thinner profiles. Not only can component not withstand the given loads; quite often one or more of their natural frequencies coincide with that of the rotor-stator interaction. Most of the research published has been on runners, while other parts of the turbine are less studied. Even though guide vanes have torsional modes with frequencies which may be close to the exiting frequency from the rotor stator interaction with the runner, no significant failures due to resonance have been reported. This paper investigates some of the possible mechanisms which may negate resonance in the torsional modes of the guide vanes including; hydrodynamic damping from the flowing water and friction in the guide vane bearings. A case study is conducted on a guide vane where the calculated natural frequency is within 10% of the excitation frequency, while no significant vibrations have been reported. Further, the findings are generalized to Francis turbines of different specific speeds. The results indicate that the dynamics in the bearings are especially important to consider to be able to predict the vibration levels of the guide vane. Having the correct friction factor in the bearing may lead to significant damping and almost eliminate any excitation of torsional eigenmodes.

Experimental and Computational Characterization of the Ferric Uptake Regulator from Aliivibrio salmonicida (Vibrio salmonicida)

Hege Lynum Pedersen,Rafi Ahmad,Ellen Kristin Riise,Hanna-Kirsti Schrøder Leiros,Stefan Hauglid,Sigrun Espelid,Bjørn Olav Brandsdal,Ingar Leiros,Nils-Peder Willassen,Peik Haugen 한국미생물학회 2010 The journal of microbiology Vol.48 No.2

The Ferric uptake regulator (Fur) is a global transcription factor that affects expression of bacterial genes in an iron-dependent fashion. Although the Fur protein and its iron-responsive regulon are well studied, there are still important questions that remain to be answered. For example, the consensus Fur binding site also known as the “Fur box” is under debate, and it is still unclear which Fur residues directly interact with the DNA. Our long-term goal is to dissect the biological roles of Fur in the development of the disease cold-water vibriosis, which is caused by the psychrophilic bacteria Aliivibrio salmonicida (also known as Vibrio salmonicida). Here, we have used experimental and computational methods to characterise the Fur protein from A. salmonicida (AS-Fur). Electrophoretic mobility shift assays show that AS-Fur binds to the recently proposed vibrio Fur box consensus in addition to nine promoter regions that contain Fur boxes. Binding appears to be dependent on the number of Fur boxes, and the predicted “strength” of Fur boxes. Finally,structure modeling and molecular dynamics simulations provide new insights into potential AS-Fur–DNA interactions.

Development and characterization of six new human papillary thyroid carcinoma cell lines.

Henderson, Ying C,Ahn, Soon-Hyun,Ryu, Junsun,Chen, Yunyun,Williams, Michelle D,El-Naggar, Adel K,Gagea, Mihai,Schweppe, Rebecca E,Haugen, Bryan R,Lai, Stephen Y,Clayman, Gary L Issued for the Endocrine Society by the Williams & 2015 The Journal of clinical endocrinology & metabolism Vol.100 No.2

<P>Cell lines are a widely used tool in cancer research. However, despite the relatively high incidence of papillary thyroid carcinoma (PTC), there are only four PTC cell lines available for international research audience.</P>