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Development of a fast-virtual CFR engine model and its use on autoignition studies

Homogenous charge compression ignition engines have been studied as an alternative to the conventional diesel combustion to attain high efficiency with ultra-low NOx and soot emissions for a wide variety of fuels. However, its usage in real applications has been restricted due to the difficulties regarding combustion control and operating range extension. The modification of the fuel characteristi

Att tala till kvinnor och vinna deras röster : Socialdemokratiska kvinnoförbundets agitation inför valet 1921

I denna uppsats studeras socialdemokratiska kvinnors organisering och kampanjmetoder vid tiden för den allmänna och lika rösträttens införande. Undersökningen visar att erfarna kvinnliga agitatorer var mycket efterfrågade och ger exempel på kvinnoförbundets strategier för att trots begränsade resurser ordna talarturnéer. I den skriftliga agitationen tilltalades kvinnliga väljare både som del av et

On the nature of mixed neurodegenerative amyloidopathies

Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common neurodegenerative diseases in the world. It has been possible to identify common denominators for AD and PD, including aggregation of the amyloid proteins amyloid-beta (Aβ) and alpha-synuclein (α-syn). Given the continued challenges in finding therapies that could stop or prevent proteinopathies such as AD or PD, it is appar

From second sound to music : A special composition inspired by advanced physics

He II or superfluid helium, which already plays an important role in the cooling of superconducting magnets and superconducting radiofrequency cavities, has now also inspired music. Composer Michael Edward Edgerton, a professor at Lund University’s Malmo Academy of Music in Sweden has written an innovative piece, “Der Rufer,” for a percussion quartet based on phenomena found in He II including: an

Serum IFNα2 measured by single-molecule array associates with systemic disease manifestations in Sjögren's syndrome

OBJECTIVES: Type I IFN (IFN-I) activation is a prominent feature of primary SS (pSS), SLE, and SSc. Ultrasensitive single-molecule array (Simoa) technology has facilitated the measurement of subfemtomolar concentrations of IFNs. Here, we aimed to measure IFNα2 in serum from pSS, SLE, and SSc using a Simoa immunoassay and correlate these levels to blood IFN-stimulated gene (ISG) expression and dise

Lika olika för alla? : Om äldrevård och tro i det lokala Sverige

Äldreomsorgen är ett fält där det finns kolliderande rättigheter.Rätten till lika omsorg för alla kan vara svår att kombinera med kraven på ett förstå den enskildes behov och att erbjuda individanpassade insatser. Inte minst i frågan om rätten till att kunna utöva sin religion och leva enligt religiösa och kulturella traditioner på ett äldreboende ställs stora krav på både verksamheter och det lok

Ribosome association primes the stringent factor Rel for tRNA-dependent locking in the A-site and activation of (p)ppGpp synthesis

In the Gram-positive Firmicute bacterium Bacillus subtilis, amino acid starvation induces synthesis of the alarmone (p)ppGpp by the RelA/SpoT Homolog factor Rel. This bifunctional enzyme is capable of both synthesizing and hydrolysing (p)ppGpp. To detect amino acid deficiency, Rel monitors the aminoacylation status of the ribosomal A-site tRNA by directly inspecting the tRNA's CCA end. Here we dis

Hfq-Assisted RsmA Regulation Is Central to Pseudomonas aeruginosa Biofilm Polysaccharide PEL Expression

To appropriately switch between sessile and motile lifestyles, bacteria control expression of biofilm-associated genes through multiple regulatory elements. In Pseudomonas aeruginosa, the post-transcriptional regulator RsmA has been implicated in the control of various genes including those related to biofilms, but much of the evidence for these links is limited to transcriptomic and phenotypic st

In Vitro Studies of Persister Cells

SUMMARY Many bacterial pathogens can permanently colonize their host and establish either chronic or recurrent infections that the immune system and antimicrobial therapies fail to eradicate. Antibiotic persisters (persister cells) are believed to be among the factors that make these infections challenging. Persisters are subpopulations of bacteria which survive treatment with bactericidal antibio

Target protection as a key antibiotic resistance mechanism

Antibiotic resistance is mediated through several distinct mechanisms, most of which are relatively well understood and the clinical importance of which has long been recognized. Until very recently, neither of these statements was readily applicable to the class of resistance mechanism known as target protection, a phenomenon whereby a resistance protein physically associates with an antibiotic t

A widespread toxin−antitoxin system exploiting growth control via alarmone signaling

Under stressful conditions, bacterial RelA-SpoT Homolog (RSH) enzymes synthesize the alarmone (p)ppGpp, a nucleotide second messenger. (p)ppGpp rewires bacterial transcription and metabolism to cope with stress, and, at high concentrations, inhibits the process of protein synthesis and bacterial growth to save and redirect resources until conditions improve. Single-domain small alarmone synthetase

A role for the Saccharomyces cerevisiae ABCF protein New1 in translation termination/recycling

Translation is controlled by numerous accessory proteins and translation factors. In the yeast Saccharomyces cerevisiae, translation elongation requires an essential elongation factor, the ABCF ATPase eEF3. A closely related protein, New1, is encoded by a non-essential gene with cold sensitivity and ribosome assembly defect knock-out phenotypes. Since the exact molecular function of New1 is unknow

Analysis of nucleotide pools in bacteria using HPLC-MS in HILIC mode

Nucleotides, nucleosides and their derivatives are present in all cells at varying concentrations that change with the nutritional, and energetic status of the cell. Precise measurement of the concentrations of these molecules is instrumental for understanding their regulatory effects. Such measurement is challenging due to the inherent instability of these molecules and, despite many decades of r

Intramolecular interactions dominate the autoregulation of escherichia coli stringent factor RelA

Amino acid starvation in Escherichia coli activates the enzymatic activity of the stringent factor RelA, leading to accumulation of the alarmone nucleotide (p)ppGpp. The alarmone acts as an intercellular messenger to regulate transcription, translation and metabolism to mediate bacterial stress adaptation. The enzymatic activity of RelA is subject to multi-layered allosteric control executed both

The Rel stringent factor from Thermus thermophilus : Crystallization and X-ray analysis

The stringent response, controlled by (p)ppGpp, enables bacteria to trigger a strong phenotypic resetting that is crucial to cope with adverse environmental changes and is required for stress survival and virulence. In the bacterial cell, (p)ppGpp levels are regulated by the concerted opposing activities of RSH (RelA/SpoT homologue) enzymes that can transfer a pyrophosphate group of ATP to the 3′

ABCF ATPases Involved in Protein Synthesis, Ribosome Assembly and Antibiotic Resistance : Structural and Functional Diversification across the Tree of Life

Within the larger ABC superfamily of ATPases, ABCF family members eEF3 in Saccharomyces cerevisiae and EttA in Escherichia coli have been found to function as ribosomal translation factors. Several other ABCFs including biochemically characterized VgaA, LsaA and MsrE confer resistance to antibiotics that target the peptidyl transferase center and exit tunnel of the ribosome. However, the diversity

A nucleotide-switch mechanism mediates opposing catalytic activities of Rel enzymes

Bifunctional Rel stringent factors, the most abundant class of RelA/SpoT homologs, are ribosome-associated enzymes that transfer a pyrophosphate from ATP onto the 3′ of guanosine tri-/diphosphate (GTP/GDP) to synthesize the bacterial alarmone (p)ppGpp, and also catalyze the 3′ pyrophosphate hydrolysis to degrade it. The regulation of the opposing activities of Rel enzymes is a complex allosteric m

The C-Terminal RRM/ACT Domain Is Crucial for Fine-Tuning the Activation of ‘Long’ RelA-SpoT Homolog Enzymes by Ribosomal Complexes

The (p)ppGpp-mediated stringent response is a bacterial stress response implicated in virulence and antibiotic tolerance. Both synthesis and degradation of the (p)ppGpp alarmone nucleotide are mediated by RelA-SpoT Homolog (RSH) enzymes which can be broadly divided in two classes: single-domain ‘short’ and multi-domain ‘long’ RSH. The regulatory ACT (Aspartokinase, Chorismate mutase and TyrA)/RRM