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Olfactory genomics of bark- and ambrosia beetles : Evolution and function of chemoreceptors

Insect behaviours, such as host and mate selection, are often mediated by chemical cues. The chemical cuesare detected by large and rapidly evolving families of chemoreceptors which include odorant receptors (ORs),gustatory receptors (GRs) and ionotropic receptors (IRs). In this thesis, I used a model system of beetle(Coleoptera) species to study the functional evolution of insect ORs, their ligan

Sparse Spatial Shading in Augmented Reality

In this work, we present a method for acquiring, storing, and using scene data to enable realistic shading of virtual objects in an augmented reality application. Our method allows for sparse sampling of the environment’s lighting condition while still delivering a convincing shading to the rendered objects. We use common camera parameters, provided by a head-mounted camera, to get lighting inform

The neurocognitive basis of confabulatory introspection : Choice blindness and the brain

The goal of this thesis is to advance our understanding of introspection by studying when it fails, without us being aware of it. To do so, I have used the choice blindness paradigm. Choice blindness is a surprising phenomenon in which people fail to detect mismatches between their intention and outcome in a decision task, and then spontaneously confabulate reasons why they preferred an alternativ

Minimal Optimism : Reading P. F. Strawson on Responsibility

Peter Strawson’s ‘Freedom and Resentment’ (1962) has reoriented the way moral philosophers think about responsibility. There is a general sense that Strawson’s approach holds the promise that we may move beyond the traditional discussion of free will in recognition of the fact that whether determinism is true is irrelevant for whether we are responsible beings. This is Strawson’s Promise. This the

Exploring the influence of patient variability on propofol target-controlled infusion performance

Target-controlled infusion (TCI) constitutes a clinically available alternative to manually administering the infusion rate of the anesthetic drug propofol. In TCI, a drug infusion profile is optimized to track a reference trajectory of blood plasma or effect site (brain cortex) drug concentration, or a corresponding clinical effect. TCI is a pure feed-forward openloop strategy, fully reliant on a

Endometriosis diagnosed by ultrasound is associated with lower live birth rates in women undergoing their first IVF/ICSI treatment

ObjectiveTo study the cumulative live birth rate (CLBR) after the first in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment in women with or without deep-infiltrating endometriosis (DIE) and/or endometrioma diagnosed by transvaginal ultrasonography (TVUS), using the International Deep Endometriosis Analysis (IDEA) group definitions.DesignProspective observational coho

Prevalence of adenomyosis features in women scheduled for assisted reproductive treatment, using the Morphological Uterus Sonographic Assessment group definitions

IntroductionStudies that use standardized ultrasonographic criteria to diagnose adenomyosis in subfertile women are needed. These would improve the understanding of the disease burden and enable further studies on its impact on fertility and assisted reproductive treatment (ART) outcome. The aim of this study was to determine the prevalence of different features of adenomyosis in women scheduled f

Nonsense-mediated mRNA decay maintains translational fidelity by limiting magnesium uptake

Inactivation of the yeast nonsense-mediated mRNA decay (NMD) pathway stabilizes nonsense mRNAs and promotes readthrough of premature translation termination codons. Although the latter phenotype is thought to reflect a direct role of NMD factors in translation termination, its mechanism is unknown. Here we show that the reduced termination efficiency of NMD-deficient cells is attributable to incre

The pre-mRNA retention and splicing complex controls tRNA maturation by promoting TAN1 expression

The conserved pre-mRNA retention and splicing (RES) complex, which in yeast consists of Bud13p, Snu17p and Pml1p, is thought to promote nuclear retention of unspliced pre-mRNAs and enhance splicing of a subset of transcripts. Here, we find that the absence of Bud13p or Snu17p causes greatly reduced levels of the modified nucleoside N(4)-acetylcytidine (ac(4)C) in tRNA and that a lack of Pml1p redu

Eukaryotic wobble uridine modifications promote a functionally redundant decoding system

The translational decoding properties of tRNAs are modulated by naturally occurring modifications of their nucleosides. Uridines located at the wobble position (nucleoside 34 [U(34)]) in eukaryotic cytoplasmic tRNAs often harbor a 5-methoxycarbonylmethyl (mcm(5)) or a 5-carbamoylmethyl (ncm(5)) side chain and sometimes an additional 2-thio (s(2)) or 2'-O-methyl group. Although a variety of models

Association of yeast Upf1p with direct substrates of the NMD pathway

Nonsense-mediated mRNA decay (NMD) is a surveillance mechanism that detects and degrades transcripts containing premature translation termination codons. Gene expression profiling experiments have shown that inactivation of the NMD pathway leads to the accumulation of both aberrant, nonsense-containing mRNAs, and many apparently wild-type transcripts. Such increases in transcript steady-state leve

Elevated levels of two tRNA species bypass the requirement for elongator complex in transcription and exocytosis

The Saccharomyces cerevisiae Elongator complex consisting of the six Elp1-Elp6 proteins has been proposed to participate in three distinct cellular processes: transcriptional elongation, polarized exocytosis, and formation of modified wobble uridines in tRNA. Therefore it was important to clarify whether Elongator has three distinct functions or whether it regulates one key process that leads to m

The Kluyveromyces lactis gamma-toxin targets tRNA anticodons

Kluyveromyces lactis killer strains secrete a heterotrimeric toxin (zymocin), which causes an irreversible growth arrest of sensitive yeast cells. Despite many efforts, the target(s) of the cytotoxic gamma-subunit of zymocin has remained elusive. Here we show that three tRNA species tRNA(Glu)(mcm(5)s(2)UUC), tRNA(Lys)(mcm(5)s(2)UUU), and tRNA(Gln)(mcm(5)s(2)UUG) are the targets of gamma-toxin. The

An early step in wobble uridine tRNA modification requires the Elongator complex

Elongator has been reported to be a histone acetyltransferase complex involved in elongation of RNA polymerase II transcription. In Saccharomyces cerevisiae, mutations in any of the six Elongator protein subunit (ELP1-ELP6) genes or the three killer toxin insensitivity (KTI11-KTI13) genes cause similar pleiotropic phenotypes. By analyzing modified nucleosides in individual tRNA species, we show th

The Saccharomyces cerevisiae TAN1 gene is required for N4-acetylcytidine formation in tRNA

The biogenesis of transfer RNA is a process that requires many different factors. In this study, we describe a genetic screen aimed to identify gene products participating in this process. By screening for mutations lethal in combination with a sup61-T47:2C allele, coding for a mutant form of, the nonessential TAN1 gene was identified. We show that the TAN1 gene product is required for formation o

Dual function of the tRNA(m(5)U54)methyltransferase in tRNA maturation

A 5-methyluridine (m(5)U) residue at position 54 is a conserved feature of bacterial and eukaryotic tRNAs. The methylation of U54 is catalyzed by the tRNA(m5U54)methyltransferase, which in Saccharomyces cerevisiae is encoded by the nonessential TRM2 gene. In this study, we identified four different strains with mutant forms of tRNA(Ser)CGA. The absence of the TRM2 gene in these strains decreased t

Identification of the TRM2 gene encoding the tRNA(m5U54)methyltransferase of Saccharomyces cerevisiae

The presence of 5-methyluridine (m5U) at position 54 is a ubiquitous feature of most bacterial and eukaryotic elongator tRNAs. In this study, we have identified and characterized the TRM2 gene that encodes the tRNA(m5U54)methyltransferase, responsible for the formation of this modified nucleoside in Saccharomyces cerevisiae. Transfer RNA isolated from TRM2-disrupted yeast strains does not contain

The Future of Fighter Pilot Training? Live Virtual Constructive in Large Force Exercises : Perceived and Expected Training Value

Objective: This study investigates whether and how perceived training value varies among fighter pilots participating in a large force exercise (LFE), and whether they expect Live Virtual Constructive (LVC) training to enhance training value of future LFEs. Background: LVC technology is maturing but its expected training value is under-investigated, especially regarding future LVC in LFEs. Method:

Exploring unmanned systems with virtual prototypes in augmented reality video

The potential of unmanned systems is vast, but pre-procurement evaluation is challenging. This study explores potential uses of and interaction with unmanned ground vehicles (UGVs) for dismounted infantry. A remote user study with Swedish Armed Forces personnel is described. Many factors influencing future use and interaction were found. Moreover, this study shows the potential of the innovative m