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Anorexia nervosa (AN) is a devastating disorder with evidence of underexplored heritability. Twin and family studies estimate heritability (h

The relevance of the study is determined as follows: insufficient attention to the educational and research activities of students in the process of learning various disciplines, in particular, chemistry; weak implementation of the potential of scientific disciplines for the educational and research activities of high school students; the need to develop the technology of creating educational research environment for secondary school students studying STEM subjects. In the conditions of constant development of science and technology, computerisation of society, integration of education and science, the requirements for graduates increase: with sufficient theoretical knowledge, it is necessary to be able to apply them in various life situations, predict possible consequences of decisions made, demonstrate social activity, interest in scientific problems and initiatives. The purpose of the study is to develop, theoretically substantiate, and experimentally test the content and pedagogical conditions of educational activities of high school students in chemistry classes. As a research method, a systematic approach was used when considering the phenomena of current chemistry teaching in the context of modern education, and a method of comparing chemistry teaching in Kazakhstan and other countries. The result of the study was the concept of a project method, which is based on a focus on the result that can be obtained when solving a specific practical or theoretically significant problem. To achieve such a result, it is necessary to teach children or adults to think independently, find and solve problems, acquire knowledge from various fields, be able to predict the results and possible consequences of various decisions, and be able to determine the causes, relationships, and consequences. It was concluded that the use of the project method increases motivation, develops creative abilities, personal qualities, and improves the learning material and knowledge of basic research methods.

Siden industrialiseringen og veksten av jernbanetransport på starten av 1800-tallet har det blitt observert flere uventede brudd i komponenter utsatt for vekslende belastning, selv om spenningene var langt under materialenes fasthetsverdier. På dette viset oppstod erkjennelsen og teorien om at materialer kan bli utmattet over tid. For å unngå alvorlige ulykker ble det viktig å forstå mekanismene bak utmattingsbrudd og danne et formelverk for dimensjonering av levetid. Utmattingsberegninger er bygget på empiriske data for ulike materialtyper. En av de første til å bygge utmattingsmaskiner og utføre denne typen tester var jernbaneingeniør August Wöhler. Han oppdaget at det var en sammenheng mellom spenningsamplituden og hvor mange lastsykler en materialprøve kan utsettes for før det går til brudd. Disse oppdagelsene legger grunnlaget for utmattingstesting og utmattingsberegninger den dag i dag. Fordi forståelse for utmattingsproblematikk er viktig for mange industrier ønsker Fakultet for realfag og teknologi ved Norges miljø- og biovitenskapelige universitet en utmattingsmaskin som kan benyttes i sammenheng med laboratoriearbeid for studenter. Det er også et ønske om at maskinen skal kunne benyttes til fremtidig FoU-arbeid. Å ha en slik testmaskin tilgjengelig på universitetet vil samtidig være med på å styrke forståelsen for utmatting av materialer. Med denne bakgrunnen er hovedmålet med mastergradsarbeidet derfor å klarlegge viktige trinn i utviklingen av denne typen maskiner, teknologisk status og viktige standarder, og bygge videre på dette for å kunne konstruere og designe en utmattingsprøvemaskin med 4-punkts bøying for testing av prøvestaver. Som en del av dette utviklingsarbeidet følger det også med en teoriutredning som gjør rede for materialtekniske mekanismer som står bak utmattingsbrudd, og hvordan initiering og vekst av sprekker foregår på mikroskopisk nivå. For å bygge opp under hovedmålsettingene er det blitt definert delmål, som igjen er videreutviklet til en tidsplan som skal sikre at alle deler av arbeidet blir gjennomført i tide. God planlegging og fokus på kvalitet og kontinuerlig forbedring er sentralt i IPD/IPPD-tankegang (Integrert produkt- og prosessutvikling), og det blir gjort nærmere rede for denne metodikken. Andre sentrale utviklingsmetodikker som benyttes er Pughs metode, SCAMPER og modulisering, samt QFD, som samler mye av utviklingsmetodikken i det såkalte «kvalitetshuset». Pughs metode er benyttet for å gjøre valg i på en objektiv måte ved å sette opp seleksjonsmatriser og veie ulike løsningsalternativer opp mot hverandre. SCAMPER ble benyttet mye i for å komme opp med løsninger og funksjoner, men også gjennomgående i arbeidet med rapportering. Modulisering er brukt til å se ulike måter elementer kan settes sammen og konstrueres, samt muligheten for å benytte eksisterende løsninger i konstruksjonen. Utredningsfasen er avsluttet med prosessdiagrammet, som også gjør rede for de tre følgende fasene: utviklingsfasen, konstruksjons-fasen og ferdigstillingsfasen. I utviklingsfasen blir krav og spesifiseringer for produktet definert. Dette inkluderer grense-spesifikasjoner for ytre mål og andre viktige dimensjoner som skal styre både aktuelle løsningsalternativer og arbeid i konstruksjonsfasen. Ved å gjennomføre en funksjonsanalyse er det kommet fram til hvilke funksjoner som er viktige og aktuelle løsninger som kan oppfylle disse funksjonene. Løsningsalternativene henter inspirasjon fra eksisterende utmattingsmaskiner og er spisset inn mot de målsettingene som er satt for prosjektet. Alle løsningsalternativer er skissert og screenet opp mot hverandre. Mot slutten av utviklingsfasen sitter man igjen med en fullstendig konseptløsning som skal videreutvikles i konstruksjonsfasen. Konstruksjonsfasen består av grovberegninger som var med på å styre dimensjoneringen av ulike produktdetaljer. Hele maskinen ble så 3D-modellert i CAD-programvare, i tillegg til tekniske sammenstillingstegninger som viser maskinen i sin helhet og alle hovedkomponenter. Utvalgte viktige komponenter gikk gjennom FEM-analyser for å finne eventuelle svakheter i konstruksjonen og optimalisere arkitekturen. En kombinasjon av grovberegninger og FEM-analyse ga grunnlaget for materialvalg for komponentene. Ferdigstillingsfasen er innledet med en gjennomgang av produksjonsmetoder og analyse av kostnader knyttet til produksjon av utmattingsmaskinen. Tegningsgrunnlaget fra konstruksjons-fasen gir grunnlag for renderinger i lab-miljø, samt anvisninger for en laboratorieøvelse i utmattingstesting. Bøyeutmattingstestmaskinen er konstruert etter standard for utmattingsprøvemaskiner (ISO 1143) og for å påføre 4-punkts bøyemoment på en prøvestav. Dette betyr at prøvestaven er innspent i 2 punkter og belastet i 2 punkter. Det oppnås vekslende spenning ved å rotere prøvestaven med en motor. Belastninger kommer fra et sett med lodd som henger fra belastningspunktene. Maskinen er stilt opp på et bord og er utstyrt med et målesystem som registrerer turtall, antall rotasjoner og tid før brudd. Utvendige mål for selve maskinen er 800 mm x 150 mm x 117,5 mm. Bordet som benyttes for oppstilling har mål 1310 mm x 590 mm x 770 mm. Driftsspenningen til motoren er 230 V, og den har et turtall på 3000 r/min. Den totale kostnaden for produksjon av en prototype er 517.515 kr. Ekskluderer man eget utviklingsarbeid er prisen 22.515 kr. Veien videre består av flere styrkeberegninger og FEM-analyser. Andre beregninger i form av utmattingsberegninger, levetidsanalyser og svingningsanalyser bør også gjennomføres. I tillegg må det gjøres design av elektrisk anlegg for motor, brytere, sensorer og databehandling. Som en del av videre arbeid burde det gjøres en endelig vurdering av produksjonsmetoder og kostnadene knyttet til dette. Since the industrialization and growth of rail transport at the beginning of the 19th century, several unexpected fractures of components subjected to varying loads have been observed, even though the stresses were far below the strength values of the materials. This led to the realization and theory that materials can become fatigued over time. To avoid serious accidents, it became important to understand the mechanisms behind fatigue failure and form a formula for dimensioning service life. Fatigue calculations are based on empirical data for different material types. One of the first to build fatigue machines and perform this type of test was railway engineer August Wöhler. He discovered that there was a connection between the stress amplitude and how many load cycles a material sample can be subjected to before it breaks. These discoveries are still the foundation for fatigue testing and fatigue recovery to this day. Because understanding fatigue problems is important for many industries, the Faculty of Science and Technology at the Norwegian University of Life Sciences wants a fatigue machine that can be used in connection with laboratory work for students. There is also a desire for the machine to be able to be used for future R&D work. Having such a test machine available at the university will at the same time help to strengthen the understanding of material fatigue. With this background, the main goal of the master's degree project is therefore to clarify important steps in the development of this type of machine, technological status and important standards, and build on this to be able to construct and design a fatigue test machine with 4-point bending for test specimens. As part of this development work, a theory study is also included that explains the material technical mechanisms behind fatigue fractures, and how the initiation and growth of cracks takes place at the microscopic level. M-MPP

Individuals living or working in moldy buildings complain of a variety of health problems including pain, fatigue, increased anxiety, depression, and cognitive deficits. The ability of mold to cause such symptoms is controversial since no published research has examined the effects of controlled mold exposure on brain function or proposed a plausible mechanism of action. Patient symptoms following mold exposure are indistinguishable from those caused by innate immune activation following bacterial or viral exposure. We tested the hypothesis that repeated, quantified doses of both toxic and nontoxic mold stimuli would cause innate immune activation with concomitant neural effects and cognitive, emotional, and behavioral symptoms. We intranasally administered either 1) intact, toxic Stachybotrys spores; 2) extracted, nontoxic Stachybotrys spores; or 3) saline vehicle to mice. As predicted, intact spores increased interleukin-1β immunoreactivity in the hippocampus. Both spore types decreased neurogenesis and caused striking contextual memory deficits in young mice, while decreasing pain thresholds and enhancing auditory-cued memory in older mice. Nontoxic spores also increased anxiety-like behavior. Levels of hippocampal immune activation correlated with decreased neurogenesis, contextual memory deficits, and/or enhanced auditory-cued fear memory. Innate-immune activation may explain how both toxic mold and nontoxic mold skeletal elements caused cognitive and emotional dysfunction.

Adult male zebra finches (Taeniopygia guttata) continually incorporate adult-born neurons into HVC, a telencephalic brain region necessary for the production of learned song. These neurons express activity-dependent immediate early genes (e.g., zenk and c-fos) following song production, suggesting that these neurons are active during song production. Half of these adult-born HVC neurons (HVC NNs) can be backfilled from the robust nucleus of the arcopallium (RA) and are a part of the vocal motor pathway underlying learned song production, but the other half do not backfill from RA, and they remain to be characterized. Here, we used cell birth-dating, retrograde tract tracing, and immunofluorescence to demonstrate that half of all HVC NNs express the phosphoprotein DARPP-32, a protein associated with dopamine receptor expression. We also demonstrate that DARPP-32+ HVC NNs are contacted by tyrosine hydroxylase immunoreactive fibers, suggesting that they receive catecholaminergic input, have transiently larger nuclei than DARPP-32-neg HVC NNs, and do not backfill from RA. Taken together, these findings help characterize a group of HVC NNs that have no apparent projections to RA and so far have eluded positive identification other than HVC NN status.

Accident investigations are an important tool for learning from accidents, by giving insight into what went wrong, and how to prevent similar accidents from happening in the future. However, there is a lack of standard guidance regarding best practices for how to execute such investigations. There are a plethora of different aspects to these investigations, as well as different alternatives and approaches for each aspect. The purpose of this thesis is to investigate how a few of these aspects might influence the outcome of the investigations, and how this in turn can influence learning potential. To answer this, the objective of this study was to find out what influence standard procedures, investigation methods, expertise, and accident models have on conclusions and safety recommendations. The study has focused on two accident boards from two different countries: the Norwegian Safety Investigation Authority (NSIA) from Norway and the National Transportation Safety Board (NTSB) from the United States. They were chosen to highlight potential cross-continental differences that could give valuable insight that both sides can learn from. The research in this thesis was done mainly through comparative document analyses, both a quantitative and qualitative approach. The qualitative analysis was used to gain insight into the fundamental differences between the two boards and entailed official documents from the two boards, as well as relevant laws and regulations regarding their mandate and responsibilities. This was in turn used as potential explanations for differences found through the quantitative analyses. The quantitative analyses included railway accident reports from the last decade and investigated the effect the different aspects had on the report’s focus, safety recommendations, socio-technical levels, and conclusions. The data collection, hypotheses and conclusions were all done in light of the theoretical context of the thesis. Throughout the thesis, I have relied on Hollnagel’s three major groups of accident models consisting of sequential, epidemiological, and systemic models; Rasmussen’s socio-technical levels; and Argyris and Schön’s distinction between double-loop and single-loop learning. Furthermore, I chose to focus on the three accident models AcciMap, MTO and STEP. This theoretical context must be considered when reviewing the results and conclusions made in this thesis. The results from the analyses implied that different standard procedures, expertise, and accident models all have a significant effect on the outcome of investigations and may influence learning potential. A larger cross-sectoral investigation board with more diverse expertise appears to give a more even distribution of safety recommendations between the different socio-technical levels, and more focus to higher levels. This could provide learning to more of the levels, as well as increasing double-loop learning by including higher levels. The results also indicate that epidemiological accident models give an increased focus on human causal factors, while systemic accident models lead to an increased focus on organizational factors. Lastly, investigation methods did not have any apparent effect, possibly due to the two accident boards having similar approaches and overlap. Both the NSIA and the NTSB have different aspects that can influence their learning potential in positive and negative ways, and it would be beneficial for both of them to learn from each other’s approaches to increase their learning from accidents.

New neurons born in the adult brain undergo a critical period soon after migration to their site of incorporation. During this time, the behavior of the animal may influence the survival or culling of these cells. In the songbird song system, earlier work suggested that adult-born neurons may be retained in the song motor pathway nucleus HVC with respect to motor progression toward a target song during juvenile song learning, seasonal song restructuring, and experimentally manipulated song variability. However, it is not known whether the quality of song per se, without progressive improvement, may also influence new neuron survival. To test this idea, we experimentally altered song acoustic structure by unilateral denervation of the syrinx, causing a poor quality song. We found no effect of aberrant song on numbers of new neurons in HVC, suggesting that song quality does not influence new neuron culling in this region. However, aberrant song resulted in the loss of left-side dominance in new neurons in the auditory region caudomedial nidopallium (NCM), and a bilateral decrease in new neurons in the basal ganglia nucleus Area X. Thus new neuron culling may be influenced by behavioral feedback in accordance with the function of new neurons within that region. We propose that studying the effects of singing behaviors on new neurons across multiple brain regions that differentially subserve singing may give rise to general rules underlying the regulation of new neuron survival across taxa and brain regions more broadly.

Adult male zebra finches (Taeniopygia guttata) continually incorporate adult-born neurons into HVC, a telencephalic brain region necessary for the production of learned song. These neurons express immediate early genes during song production, suggesting a role for neurogenesis in song production throughout the lifespan. Half of these adult-born HVC neurons (HVC NNs) can be backfilled from the robust nucleus of the arcopallium (RA) and are a part of the vocal motor pathway underlying learned song production, but the other half do not backfill from RA, and they remain to be characterized. Here we used cell birth-dating, retrograde tract tracing, and immunofluorescence to demonstrate that half of all HVC NNs express thephosphoprotein DARPP-32, a protein associated with dopamine (DA) receptor expression. We also demonstrate that DARPP-32+ HVC NNs are contacted by tyrosine hydroxylase immunoreactive fibers suggesting that they receive catecholaminergic input, have transiently larger nuclei than DARPP-32− HVC NNs, and do not backfill from RA. Taken together, these findings help characterize a group of HVC NNs that have no apparent projections to RA and so far have eluded any positive identification other than HVC NN status.

Objective To test the hypothesis that rs573116164 will have disease-modifying effects in patients with superoxide dismutase 1 (SOD1) familial amyotrophic lateral sclerosis (fALS), we characterized rs573116164 within a cohort of 190 patients with fALS and 560 healthy age-matched controls to assess the variant for association with various measures of disease. Methods Using a previously described bioinformatics evaluation algorithm, a polymorphic short structural variant associated with SOD1 was identified according to its theoretical effect on gene expression. An 12–18 poly-T repeat (rs573116164) within the 3′ untranslated region of serine and arginine rich proteins-related carboxy terminal domain associated factor 4 (SCAF4), a gene that is adjacent to SOD1, was assessed for disease association and influence on survival and age at onset in an fALS cohort using PCR, Sanger sequencing, and capillary separation techniques for allele detection. Results In a North American cohort of predominantly SOD1 fALS patients (n =190) and age-matched healthy controls (n = 560), we showed that carriage of an 18T SCAF4 allele was associated with disease within this cohort (odds ratio [OR] 6.6; 95% confidence interval [CI] 3.9–11.2; p = 4.0e-11), but also within non-SOD1 cases (n = 27; OR 5.3; 95% CI 1.9–14.5; p = 0.0014). This finding suggests genetically SOD1-independent effects of SCAF4 on fALS susceptibility. Furthermore, carriage of an 18T allele was associated with a 26-month reduction in survival time (95% CI 6.6–40.8; p = 0.014), but did not affect age at onset of disease. Conclusions The findings in this fALS cohort suggest that rs573116164 could have SOD1-independent and broader relevance in ALS, warranting further investigation in other fALS and sporadic ALS cohorts, as well as studies of functional effects of the 18T variant on gene expression.

The underlying genetic and molecular mechanisms that drive amyotrophic lateral sclerosis (ALS) remain poorly understood. Structural variants within the genome can play a significant role in neurodegenerative disease risk, such as the repeat expansion in C9orf72 and the tri-nucleotide repeat in ATXN2, both of which are associated with familial and sporadic ALS. Many such structural variants reside in uncharacterized regions of the human genome, and have been under studied. Therefore, characterization of structural variants located in and around genes associated with ALS could provide insight into disease pathogenesis, and lead to the discovery of highly informative genetic tools for stratification in clinical trials. Such genomic variants may provide a deeper understanding of how gene expression can affect disease etiology, disease severity and trajectory, patient response to treatment, and may hold the key to understanding the genetics of sporadic ALS. This article outlines the current understanding of amyotrophic lateral sclerosis genetics and how structural variations may underpin some of the missing heritability of this disease.