Les nanoparticules métalliques ont la particularité de fritter à des températures bien inférieures que les microparticules. Les pâtes de frittage à base de nanoparticules d'argent (Ag) sont commercialisées pour assembler des puces d'électronique de puissance à leur substrat. L’assemblage se fait classiquement entre 200 et 300°C, sous contrainte. Le joint métallique final obtenu possède d’excellentes propriétés de conductivités électrique et thermique. La température de fusion théorique du joint, une fois densifié, est égale à la température de fusion de l’Ag massif (962°C). Cette propriété fait de ce nanomatériau une excellente alternative dans l’électronique de puissance « haute température ». Le coût de l’argent, qui est un métal précieux, reste un frein à l’utilisation de ces pâtes de frittage. Une alternative pour baisser les coûts est de remplacer les nanoparticules d’argent par des nanoparticules de cuivre. Le cuivre possède des propriétés de conductivités très proches de celles de l’argent. Un obstacle majeur à l’intégration de nanoparticules de cuivre dans des pâtes de frittage est la propension du cuivre à s’oxyder. L’oxydation des nanoparticules empêche le frittage et diminue fortement les propriétés mécaniques ainsi que la conductivité du joint métallique final. En plus de cela, le cuivre, même non oxydé, est moins réactif lors du frittage et nécessite des températures plus élevées pour une bonne densification que l’argent. La stratégie choisie pour protéger les nanoparticules de cuivre de l’oxydation a été de les encapsuler dans un polymère ou avec une fine couche d’argent. L’obtention de systèmes cœur-coquille Cu@Ag, en plus d’augmenter la résistance face à l’oxydation, permet d’améliorer le frittage des joints. Une fois densifiés, les joints à base de nanoparticules Cu@Ag sont capables de résister à des contraintes mécaniques élevées. / Metallic nanoparticles have the particularity to sinter at lower temperatures compared to microparticles. Silver (Ag) nanoparticles based sintering pastes are commercially available for assembling power electronics chips to their substrates. The assembly is performed between 200 and 300°C, generally under pressure (Hot Pressing) and the resulting metallic joint has excellent thermal and electrical conductivity properties. The theoretical melting temperature of the resulting densified joint corresponds to the melting temperature of bulk silver (962°C), making the silver nanoparticles an alternative for "high temperature" power electronics compared to traditional solder. Nevertheless, the cost of Ag, which is a precious metal, remains a barrier to the use of these sintering pastes. The cost can be reduced by replacing the silver nanoparticles with copper (Cu) nanoparticles. Copper has conductive properties very close to silver. The major hurdle to the integration of copper nanoparticles in sintering pastes is the proneness of copper to oxidation. The oxidation of Cu nanoparticles prevents sintering and greatly reduces the mechanical properties and conductivity of the final metallic joint. Moreover, copper is less reactive during sintering and requires higher temperatures to densify. We chose to protect copper nanoparticles by encapsulation. In a first step copper nanoparticles were synthetized at laboratory scale and semi-industrial scale. In a second step the copper nanoparticles were encapsulated either with a polymer or very thin layer of Ag. The oxidation properties of the core-shell nanoparticles were studied. In a third step the Cu@Ag nanoparticles were formulated in a paste in order to obtain metallic joints. The sintering and density properties of the metallic joints were evaluated and positively compared to the joints obtained with a commercial Ag based paste. The Cu@Ag core-shell system prevents oxidation but also improves the sintering process.

<p>Synthetic biology reprograms organisms to perform non-native functions for beneficial reasons. An important practice in synthetic biology is the ability to edit DNA to change a base pair, disrupt a gene, or insert a new DNA sequence. DNA edits are commonly made with the help of homologous recombination, which inserts new DNA flanked by sequences homologous to the target region. To increase homologous recombination efficiency, a double stranded break is needed in the middle of the target sequence. Common methods to induce double stranded breaks use nucleases, enzymes that cleave ribonucleotides (DNA and RNA). The most common nucleases are restriction enzymes, which recognize a short, fixed, palindromic DNA sequence (4-8 base pairs). Because of the short and fixed nature of the recognition sites, restriction enzymes do not make good candidates to edit large chromosomal DNA. Alternatively, scientists have turned to programmable endonucleases which recognize user-defined DNA sequences, often times much larger than the recognition sites of restriction enzymes (15-25 base pairs). Programmable endonucleases such as CRISPR-based systems and prokaryotic Argonautes are found throughout the prokaryotic kingdom and may differ significantly in activity and specificity. To compare activity levels among endonuclease enzymes, activity assays are needed. These assays must clearly delineate dynamic activity levels of different endonucleases and work with a wide variety of enzymes. Ideally, the activity assay will also function as a positive selection screen, allowing modifications to the enzymes via directed evolution. Here, we develop an <i>in vivo</i> assay for programmable endonuclease activity that can also serve as a positive selection screen using two plasmids, a lethal plasmid to cause cell death and a rescue plasmid to rescue cell growth. The lethal plasmid houses the homing endonuclease, I-SceI, which causes a deadly double-stranded break at an 18 base pair sequence inserted into an engineered <i>E. coli</i> genome. The rescue plasmid encodes for a chosen endonuclease designed to target and cleave the lethal plasmid, thereby preventing cell death. With this, cell growth is directly linked to programmable endonuclease activity. Three endonucleases were tested, SpCas9, eSpCas9, and xCas9, displaying recovered growth of 49.3%, 26.1%, and 16.4% respectively. These values translate to kinetic enzymatic activity and are congruent with current literature findings as reported values find WT-SpCas9 to have the fastest kinetics cleaving around 95% of substrate within 15 seconds, followed closely by eSpCas9 cleaving 75% of substrate within 15 seconds and finally trailed by xCas9 cleaving 20% of substrate in about 30 seconds. The differences between each endonuclease’s activity is exacerbated in our <i>in vivo</i> system when compared to similar <i>in vitro</i> methods with much lower resolution. Therefore, slight differences in activity between endonucleases within the first few minutes in an <i>in vitro</i> assay may be a few percentages different whereas in our <i>in vivo</i> assay, these differences in activity result in a more amplified signal. With the ability to display the dynamic response of enzymes, this assay can be used to compare activity levels between endonucleases, give insight into their kinetics, and serve as a positive selection screen for use in directed evolution applications. </p>

Problemställning Barns användning av elektroniska skärmar har ökat de senaste åren. Deras skärmanvändning påverkas av deras föräldrars användning och uppfattning till elektroniska skärmar. Distriktssköterskans roll inom elevhälsan är att hjälpa barn och familjer till hälsosamma vanor, även avseende skärmanvändning. Syfte Syftet var att beskriva föräldrars uppfattning om sina barns skärmanvändning. Metod Datainsamling gjordes med kvalitativa frågeformulär med öppna frågor. Materialet analyserades enligt fenomenologisk metod. Resultat Resultatet av studien visar att föräldrars uppfattning kring sina barns skärmanvändning är positiv. Föräldrar upplever att barns skärmanvändning bör begränsas samt att det är svårt. Skärmen kan vara en resurs för att söka kunskap samt sociala kontakter mellan barn via sociala medier. Konklusion Föräldrars uppfattning om sina barns skärmanvändning är både positiv och negativ. Skärmanvändning upplevs som bra när den används i pedagogiskt syfte eller bidrar till ökad fysisk aktivitet. Fortsatta studier Implikationer är studier som undersöker ämnet ur distriktssköterskans perspektiv, både avseende möjlighet till kommunikation med föräldrar samt hur föräldrar och distriktssköterskan kan samverka mot ogynnsam skärmanvändning bland barn. / Problem Children’s use of electronic devices such as smartphones and tablets has increased in recent years. Research shows that children’s screen usage is influenced by their parent’s use and perception of electronic screens. The role of the district nurse in student health is to help children and families with healthy habits, including regarding screen usage. Aim The aim of this study was to describe parent’s perceptions of their children’s screen usage. Method The data collection was done with qualitative open-ended questionnaires. The material was analyzed by phenomenological method. Results The results of the study show that parent’s perception of their children’s screen usage is positive. Parents feel that children’s screen usage should be limited and that it is difficult. The screen can be a resource for seeking knowledge as well as social contacts between children via social media. Conclusion Parents' perceptions of children's screen usage are both positive and negative. Screen usage is perceived as good when it’s used for educational purposes or contributes to increased physical activity. Further studies Implications are studies that investigate the topic from the district nurse's perspective, both regarding the possibility of communication with parents and how parents and the district nurse can work together against unfavorable screen usage among children

In the last decade, the use of digital devices such as television, smartphones, computers, laptops, and tablets has drastically increased. The development of technology has made it possible for the individual to be qickly stimulated and have information available at anytime and anywhere through various digital devices. This development has increased the screen time on these digital devices, which potentially can have psychological effects and influence attentional abilities. The aim of this study was therefore to investigate relationships between screen use in everyday life and different forms of attention (focused attention, devided attention, sustained attention, selective attention, motivated attention) in adults over 18 years of age. A questionnaire with questions about screen time and perceived attention in everyday life was sent out and answered online by total of 26 participants. A correlation analysis was performed on the collected data and the results showed no significant correlation between respective type of attention (including a measure of total attention) and screen time. Several factors may have influenced the results of this study, such as sample size, age group, choice of method, and that an objective measure of attention was not used.

Bakgrund: Skärmtid har ökat i samhället och även barn använder sig mycket av skärm såsom mobil, surfplattor och tv. Forskningen om hur barn påverkas av skärmar fortgår och visar på både positiva och negativa effekter. Barnhälsovårdssjuksköterskans [BHV-sjuksköterskans] uppdrag är att arbeta hälsofrämjande för barnet och stötta familjer till god hälsa. Syfte: Syftet var att undersöka BHV-sjuksköterskans erfarenheter av att samtala med föräldrar om barns hälsa i relation till skärmtid. Metod: Studien baserades på en kvalitativ metod där semistrukturerade intervjuer genomfördes med sju BHV-sjuksköterskor. Resultatet analyserades genom kvalitativ innehållsanalys. Resultat: Intervjuerna resulterade i två kategorier “Att vara ett stöd” och “Att samtala om ett svårt men viktigt ämne” och sex subkategorier “Att skapa en tillitsfull relation”, “Ge information och råd”, “Ge föräldrar stöd till egen reflektion”, “Betydelsen av kunskap”, “Betydelsen av att ha rutiner” och “Ett ökat behov av att samtala om skärmtid”. Diskussion: BHV-sjuksköterskan har en viktig stödjande roll för att främja barns hälsa relaterat till skärmtid. En tillitsfull relation med föräldrarna ligger till grund för att kunna ge bra stöd och rådgivning som kan leda till bättre hälsa för barnet. Flera deltagare upplevde svårigheter i samtalet på grund av föräldrars reaktioner samt brist på mer djupgående kunskap inom ämnet. Slutsats: BHV-sjuksköterskor behöver få mer djupgående kunskap i hur skärmtid påverkar barns hälsa och hur samtalet om skärmtid kan föras med föräldrar. Mer forskning behövs kring BHV-sjuksköterskans roll i att främja barns hälsa genom att stötta familjer till att ha ett hälsosamt förhållningssätt till skärmtid. / Background: Screen time has increased in society and even young children spend much time in front of screens such as mobile phones, tablets and televisions. New research on how children are affected by the screens is being made with both positive and negative effects. The task of the child health nurse is to promote and support families to achieve good health for the child. Aim: The aim was to investigate the experience of the child health nurse when talking to parents about their children’s health in relation to screen time. Method: The study was based on a qualitative method with semi-constructed interviews conducted with seven child health nurses. The results were analyzed with a qualitative content analysis. Results: Two categories “To be a support” and “To talk about a difficult but important subject” and six subcategories “To create a trustworthy relationship”, “To give information and advice”, “Parents support to their own reflections”, “The value of knowledge”, “The value of routines” and “An increased need to talk about screen time” was found. Discussion: The child health nurse has an important role when it comes to supporting and promoting the children’s health in relation to screen time. A trusting relationship with the parents is the foundation to fulfill this role. Several participants experienced difficulties in their conversations based on the parents' reactions and their own lack of deeper knowledge on the subject. Conclusion: Child health nurses need more knowledge in how screen time affects children's health and how to deal with this subject with parents in general. More research is needed on how the child health nurse work support families to promote children’s health in the relationship to screen time. / <p>Datum för godkännande: 2021-11-01.</p>

Projekt av ett förslag på Operahus vid Stadsgårdskajen i Stockholm med nischning mot ljus- och videoinstallationer. Den publika ytan framför byggnaden integreras med de administrativa aktiviteterna i Operahuset i ett programmerbart landskap.

This project is centered around the use of finite element analysis for developing a beam for a new type of motor used in a screening machine. Essentially the main purpose of the developed beam is to transfer vibrations to the screen machine that it will be attached to. Since the machine operates on vibrations from the motor, the beam was to be designed with material fatigue in mind, which demanded examination of stresses in the welded joints of the beam. Concepts were generated with a specification of requirements as a basis, and the concepts were then analysed with finite element analysis. The results from this analysis were compared and a final design choice was selected. Since the beam will be subjected to varying fatigue loads, an S-N curve was needed to gain information of the material’s cyclic stress versus life. Most S-N curves are accessible through literature or databases, however, there are some materials that do not have an S-N curve available. If that is the case then the designer has the option to estimate one using ultimatetensile strength and the material’s fatigue limit. Hence, an S-N curve was estimated in this project.

Tekniken utvecklas kontinuerligt och vår miljö har gradvis blivit mer digitaliserad med åren. Numera finns det således en ständig närvaro av olika digitala enheter i våra liv, såsom smartphonen. Syftet med forskningsstudien är att undersöka hur användarens beteendemönster vid användning av smartphones påverkas av ett svartvitt tema. För att svara på forskningsmålet valde författarna till studien att undersöka hur unga vuxnas spenderade tid på sina smartphones digitala skärmar påverkas av ett svartvitt tema, samt hur unga vuxna upplever den spenderade tiden på deras smartphones digitala skärmar när dessa är inställda på ett svartvitt tema. Litteraturstudien, som baserades på tidigare forskning om visualisering och digitalt beroende, gav en grund för att analysera, förklara och diskutera de insamlade empiriska data. Studien genomfördes med en mixad metod, där kvantitativa data som samlades in från sju deltagare analyserades med hjälp av det statistiska analysprogrammet SPSS; och kvalitativa data som samlades in genom individuella intervjuer med de sju deltagarna analyserades tematiskt. Resultaten visade att användarnas spenderade skärmtid på deras smartphones minskade när de ställdes in på ett svartvitt tema. Således har gråskalan en signifikant effekt på den spenderade skärmtiden. Dessutom visade resultaten att enheten inte var lika tilltalande och intressant för användarna. Gråskalan påverkade dessutom användarnas förmåga att koncentrera sig när de använde smartphone-enheten samt att användarnas koncentration blev svårare att underhålla, och navigeringen på skärmarna blev mer komplicerad. / The technology is under continuous development and our environment has gradually become more digitalized over the years. Nowadays, thus, there is a constant presence of various digital devices in our lives, such as the smartphone. The purpose of the research study is to investigate how user’s behavior patterns of the use of smartphones is affected by a black and white theme. To answer the research aim, the authors of the study chose to investigate how young adults' spent time on their smartphones’ digital screens is affected by a black and white theme, and how young adults experience the time spent on their smartphones’ digital screens when these are set on a black and white theme. The literature review, which was based on previous research on visualization and digital addiction, provided a basis for analyzing, explaining and discussing the collected empirical data. The study was conducted using a mixed methods approach, where quantitative data collected from seven participants were analyzed using the statistical analysis program SPSS; and qualitative data collected through individual interviews with the seven participants were analyzed thematically. The findings showed that the users’ spent screen time on their smartphones was reduced when it was turned into black and white theme. Thus, the gray scale has a significant effect on the spent screen time.  In addition, the findings showed that the device was not appealing and interesting for the users. Furthermore, the gray scale affected the ability of the users to concentrate, when using the smartphone device. Users’ concentration became more difficult to maintain, and the navigation on the screens became more complicated.

Quinoa has been utilized for millennia in the Andes region of South America as a nutritious and hardy food crop. In recent years interest in quinoa has grown as need increases for an alternative to traditional cereal crops that can tolerate marginal environments while offering superior nutrition. Growers outside the Andes have experienced several complications adopting quinoa, including undesirable secondary metabolites, poor yield, lodging, and height inconsistency. Unfortunately, access to native ecotypes for crop improvement is limited, and desirable traits are difficult to introduce into available quinoa cultivars because of its allotetraploid genome and tendency to self-pollinate. A genome-wide survey of induced mutations in 244 sequenced M2 families was created from a bank of EMS-treated quinoa seeds and assembled into a library of mutant lineages with predicted variants and their effects on genes to assist in identifying agronomically valuable mutations in target genes as a supplement to crop improvement efforts. Using this library, eight families containing mutations in genes associated with reduced height "GAI1, GA20OX, GID1, and L " were identified. Several individuals exhibited a shorter than average phenotype; however, because each family contains thousands of EMS-induced mutations, the causative mutation of the reduced height phenotype in each family could not be definitively identified. In one family, absence of the GAI1 mutant allele, but the presence of a mutant CKX3 allele, provided a correlation between a mutation and the short phenotype. Genotyping each generation would be required for a targeted mutant allele to be tracked through selection.

La caractérisation des tumeurs malignes et la compréhension des mécanismes de résistance aux traitements anticancéreux sont essentielles pour la découverte de nouvelles cibles thérapeutiques. Les criblages génétiques, devenus encore plus puissants avec la technologie d’édition du génome CRISPR-Cas9, le séquençage nouvelle génération et la bioinformatique, sont des outils formidables pour décrypter de nouveaux mécanismes cellulaires, dont la résistance au traitement. La leucémie myéloïde chronique (LMC) est un syndrome myéloprolifératif qui est caractérisé par l’anomalie génétique t(9;22). Cette aberration chromosomique est à l’origine du gène de fusion BCR-ABL1 qui code l’oncogène du même nom responsable de la prolifération anarchique des cellules. L’imatinib mesylate, un inhibiteur de tyrosine kinase, élimine de manière spécifique les cellules leucémiques en ciblant et en bloquant l’activité kinase de cette protéine. Malheureusement, comme pour tout type de thérapie ciblée, une résistance au traitement survient chez certains patients. Afin de repérer des nouvelles voies de résistance à cet inhibiteur de tyrosine kinase, nous avons effectué un criblage génétique avec la librairie « genome-scale CRISPR knock-out » (GeCKO v2) in vitro dans la lignée cellulaire K562. Nous avons découvert plusieurs gènes qui semblent être essentiels pour la réponse au traitement par imatinib, tels que les facteurs pro-apoptotiques BIM et BAX, ou le répresseur de la voie des MAPK, SPRED2. Le rétablissement spécifique de l’apoptose dans les cellules BIM knock-out (KO) par des BH3-mimétiques, ou l’inhibition ciblée de la voie MAPK dans la lignée SPRED2 KO sensibilise de nouveau les lignées résistantes. Dans ce travail, nous avons découvert des mécanismes de résistance déjà connus (l’apoptose, la voie MAPK…) mais nous avons également démontré l’implication de voies peu connues telles que le complexe Mediator, la maturation de ARNm et l’ubiquitinylation de protéines. Spécifiquement cibler ces lésions génétiques avec des thérapies ciblées combinées peut permettre de surmonter les phénotypes de résistance et ouvre la porte à l’utilisation de l’oncologie de précision. / The characterization of malignant tumour growth and the understanding of resistance mechanisms to treatment in cancer is of utmost importance for the discovery of novel “druggable” targets. Efficient genetic screening, now even more possible with the convergence of CRISPR-Cas9 gene editing technology, next-generation sequencing and bioinformatics, is an important tool for deciphering novel cellular processes, such as resistance to treatment in cancer. Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterised by the t(9;22) genetic abnormality, which encodes the driver of CML, the BCR-ABL1 fusion protein. Imatinib mesylate, a tyrosine kinase inhibitor, specifically eliminates CML cells by targeting and blocking the kinase activity of this protein, yet, as for all targeted therapies in cancer, resistance to treatment exists. In order to discover alternative BCR-ABL1 independent mechanisms of imatinib resistance, we utilized the genome-scale CRISPR knock-out library GeCKO v2 to screen for imatinib sensitising genes in vitro on K562 cells. We revealed genes that seem essential for imatinib induced cell death, such as pro-apoptotic genes (BIM, BAX) or MAPK inhibitor SPRED2. Specifically re-establishing apoptotic capabilities in BIM knock-out (KO) cells with BH3-mimetics, or inhibiting MAP-kinase signalling in SPRED2 KO cells with MEK inhibitors restores sensitivity to imatinib, overcoming resistance phenotypes. In this work, we discovered previously identified pathways (apoptosis, MAP-kinase signalling) and novel pathways that modulate response to imatinib in CML cell lines, such as the implication of the Mediator complex, mRNA processing and protein ubiquitinylation. Targeting these specific genetic lesions with combinational therapy can overcome resistance phenotypes and paves the road for the use of precision oncology.