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Stochastic population dynamics: The Poisson approximation

We introduce an approximation to stochastic population dynamics based on almost independent Poisson processes whose parameters obey a set of coupled ordinary differential equations. The approximation applies to systems that evolve in terms of events such as death, birth, contagion, emission, absorption, etc., and we assume that the event-rates satisfy a generalized mass-action law. The dynamics of

Impact and risk factors for early-onset group B streptococcal morbidity: analysis of a national, population-based cohort in Sweden 1997-2001

Objectives To study early-onset group B streptococcal (EOGBS) morbidity, mortality, and maternal risk factors. Design Observational, population-based, retrospective. Data from national registers and medical records. Setting Sweden, 1997-2001. Population Cohort of 640 infants with a diagnosis of GBS infection out of 435 070 live births. Method Infants with diagnoses GBS sepsis (P36.0) and/or pneumo

An ecological 'footprint' of climate change

Recently, there has been increasing evidence of species' range shifts due to changes in climate. Whereas most of these shifts relate ground truth biogeographic data to a general warming trend in regional or global climate data, we here present a reanalysis of both biogeographic and bioclimatic data of equal spatio-temporal resolution, covering a time span of more than 50 years. Our results reveal

Vegetation and land-use in the Småland Uplands, southern Sweden, during the last 6000 years

Palaeoecological methods were applied to peat and sediment cores recovered from one bog (Bråtamossen) and two lakes (Avegöl and Femtingagölen) in the Småland Uplands, southern Sweden. The general aim was to reconstruct the landuse and vegetation history for the last 6000 years in this agriculturally marginal region. The main technique was pollen analysis, which was complemented by mineral magnetic

Influence of liver cancer on lipid and lipoprotein metabolism

Liver plays a key role in the metabolism of plasma apolipoproteins, endogenous lipids and lipoproteins. Hepatocellular carcinoma (HCC) is one of the most common fatal malignant tumors in China and in other Southeast Asian countries. This has been attributed to the high incidence of hepatitis B infection. Hepatitis B proteins, such as the hepatitis B X protein (HBx) that is large hepatitis B surfac

Quantum Chemistry Can Locally Improve Protein Crystal Structures

We have re-refined the X-ray structure of the heme site in cytochrome c553, supplementing the crystallographic data with quantum chemical geometry optimizations, instead of the molecular mechanics force field used in standard crystallographic refinement. By comparing the resulting structure, obtained using medium-resolution data (170 pm), with an atomic-resolution structure (95 pm) of the same pro

Intestinal Mucosa Reconstitution and Protection: Impact of Luminal Factors

The gastrointestinal mucosa is one of the most rapidly proliferating tissues in the body, and serves as a barrier to luminal bacteria and toxins. Enteral nutrition, luminal fiber and probiotics are of crucial importance for the integrity of this barrier. We examined the potential beneficial effects of lactobacilli and fiber on methotrexate-induced enterocolitis and radiation-induced intestinal inj

Delineation of the earliest lineage commitment steps of haematopoietic stem cells: new developments, controversies and major challenges

Purpose of review This review addresses recently reported evidence for alternative cellular pathways for haematopoietic stem cell lineage commitment. Recent findings Using various approaches, several laboratories suggested the existence of adult as well as foetal multipotent progenitor cells with combined B cell, T cell and granulocyte/macrophage potential, but little or no megakaryocyte/erythroid

Att bli fosterbarn i tonåren : Om frigörelsen från internaliserade föräldraobjekt

Popular Abstract in Swedish Avhandlingens syfte är att öka förståelsen för vad det innebär för tonåringar att placeras i fosterhem. en utgångspunkt tas inom objektrelationsteori: relationen till de egna föräldrarna har betydelse för hur tonåringen hanterar separationen från dem, liksom för hur han/hon relaterar till fosterföräldrarna. 27 tonåringar i åldern 13-16 år undersöktes 2-3 månader efter dThe aim of the study is to improve on the understanding of the implications for adolescents of being placed in foster care. The basis for the study is that the adolescents´ previous relationship with their parents has significance for the manner in which the adolescents will handle the separation from the parents and how they will relate to foster parents. 27 adolescents aged 13-16 years were exam