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The dragon simulations: globular cluster evolution with a million stars

Introducing the dragon simulation project, we present direct N-body simulations of four massive globular clusters (GCs) with 106 stars and 5 per cent primordial binaries at a high level of accuracy and realism. The GC evolution is computed with nbody6++gpu and follows the dynamical and stellar evolution of individual stars and binaries, kicks of neutron stars and black holes (BHs), and the effect

Cataclysmic variables in globular clusters . First results on the analysis of the MOCCA simulations database

In this first investigation of the MOCCA database with respect to cataclysmic variables, we found that for models with Kroupa initial distributions, considering the standard value of the efficiency of the common-envelope phase adopted in BSE, no single cataclysmic variable was formed only via binary stellar evolution, i. e., in order to form them, strong dynamical interactions have to take place.

Formation mechanisms of IMBH in globular clusters

We very briefly discuss proposed in the literature possible scenarios for intermediate mass black holes formation in globular clusters. We also discuss the results of the MOCCA simulations of about 2000 models (BigSurvey) regarding the distribution of events connected with electromagnetic and gravitational radiations, namely: mass transfer on IMBH, collisions and mergers with IMBH and mergers with

MOCCA code for star cluster simulations - IV. A new scenario for intermediate mass black hole formation in globular clusters

We discuss a new scenario for the formation of intermediate mass black holes (IMBHs) in dense star clusters. In this scenario, IMBHs are formed as a result of dynamical interactions of hard binaries containing a stellar-mass black hole (BH), with other stars and binaries. We discuss the necessary conditions to initiate the process of intermediate mass BH formation and the influence of an IMBH on t

Monte Carlo modeling of globular star clusters: many primordial binaries and IMBH formation

We will discuss the evolution of star clusters with a large initial binary fraction, up to 95%. The initial binary population is chosen to follow the invariant orbital-parameter distributions suggested by Kroupa (1995). The Monte Carlo MOCCA simulations of star cluster evolution are compared to the observations of Milone et al. (2012) for photometric binaries. It is demonstrated that the observed

A Novel secreted endoglycosidase from Enterococcus faecalis with activity on human immunoglobulin G and ribonuclease B

The human pathogen Enterococcus faecalis can degrade the N-linked glycans of human RNase B to acquire nutrients, but no gene or protein has been associated with this activity. We identified an 88-kDa secreted protein, endoglycosidase (Endo) E, which is most likely responsible for this activity. EndoE, encoded by ndoE, consists of an α-domain with a family 18 glycosyl hydrolase motif and a β-domain

Bacterial Modulation of Fc Effector Functions

Immunoglobulins (Igs, antibodies) are key players in adaptive immunity, and pathways mediated through the effector Fc portion of Ig are instrumental in controlling bacterial infections. Therefore, it is not very surprising that bacterial pathogens and commensals through co-evolution with their hosts have learned many tricks to interfere with Fc effector functions. In this chapter, we describe thre

Synergism between a novel chimeric lysin and oxacillin protects against infection by methicillin-resistant Staphylococcus aureus

Staphylococcus aureus is the causative agent of several serious infectious diseases. The emergence of antibiotic-resistant S. aureus strains has resulted in significant treatment difficulties, intensifying the need for new antimicrobial agents. Toward this end, we have developed a novel chimeric bacteriophage (phage) lysin that is active against staphylococci, including methicillin-resistant S. au

On the Growth of Bone through Stress Driven Diffusion and Bone Generation Processes

För att bättre kunna förebygga att skelettet bryts ner vid långvarig vila eller vid sjukdomarsom osteopenia och osteoporos, behövs bättre förståelse för de processer somstyr detta. I den här avhandlingen antas att den primära orsaken till bentillväxt är enförändring i den kemiska miljön i benet. Förändringen antas orsakas av att tillväxtstimulerandeämnen transporteras genom benet till den plats däIn order to prevent or modify bone degeneration due to rest or due to diseases such as osteopenia and osteoporosis, the modeling and remodeling of bone tissue must be better understood. In this thesis it is assumed that the primary condition leading to bone growth is a change of the chemical environment caused by transport of matter resulting from stress driven diffusion. The change in the chemica

Ett nytt cellskelett i kampen mot cancer

Forskare vid Lunds universitet har upptäckt ett cellskelett som ger struktur åt mito-kondrierna, cellens energifabriker. Skelettet är nödvändigt för mitokondriernas funktion, men forskarna fann även att cancerceller trots defekter utnyttjar skelettet för att kunna bibehålla sin energiproduktion – och därigenom överleva. Cellskelettet i mitokondrierna fungerar ungefär som ett armeringsnät och hjälp

Gamma-tubules — novel filaments in the fight against cancer

The word skeleton sounds very significant, and indeed humans could not exist without a skeleton! Similarly, a cellular skeleton or cytoskeleton is crucial for the functions of a cell. Several different types of cytoskeleton have been identified that are necessary, for among other things, muscle movement and the activities of the brain, and consequently humans could not function at all without cytosk

Report of the international conference on manufacturing and testing of pluripotent stem cells

Sessions included an overview of past cell therapy (CT) conferences sponsored by the International Alliance for Biological Standardization (IABS). The sessions highlighted challenges in the field of human pluripotent stem cells (hPSCs) and also addressed specific points on manufacturing, bioanalytics and comparability, tumorigenicity testing, storage, and shipping. Panel discussions complemented t

κλώταξ och κνώδαξ: ett sällsynt ord och dess synonym

Ordet κλώταξ är känt från en enda bevarad antik grekisk text, Kosmas Indikopleustes’ Topographia Christiana, där det förekommer sammanlagt fyra gånger. Översättare och lexikografer har haft besvär med ordet. Detta är ett försök att närmare precisera dess betydelse samt att göra det troligt att κλώταξ är synonymt med det något vanligare κνώδαξ.

Genetic and environmental factors affecting birth size variation : A pooled individual-based analysis of secular trends and global geographical differences using 26 twin cohorts

Background: The genetic architecture of birth size may differ geographically and over time. We examined differences in the genetic and environmental contributions to birthweight, length and ponderal index (PI) across geographical-cultural regions (Europe, North America and Australia, and East Asia) and across birth cohorts, and how gestational age modifies these effects. Methods: Data from 26 twin