Sökresultat

We present detailed chemical element abundance ratios of 17 elements with eight <= Z <= 60 in three metal-poor stars in the Ursa Minor dwarf spheroidal galaxy, which we combine with extant data from the literature to assess the predictions of a novel suite of galaxy chemical evolution models. The spectroscopic data were obtained with the Keck/High-Resolution Echelle Spectrograph instrument and rev

Synchronized activity is common during various physiological operations but can culminate in seizures and consequently in epilepsy in pathological hyperexcitable conditions in the brain. Many types of seizures are not possible to control and impose significant disability for patients with epilepsy. Such intractable epilepsy cases are often associated with degeneration of inhibitory interneurons in

The whiH gene is required for the orderly sporulation septation that divides aerial hyphae into spores in Streptomyces coelicolor. Here, we use a whiHp-mCherry transcriptional reporter construct to show that whiHp is active specifically in aerial hyphae, fluorescence being dependent on sporulation sigma factor WhiG. The results show that the promoter is active before the septation event that separ

The generation of toxic oligomers during the aggregation of the amyloid-beta (A beta) peptide A beta 42 into amyloid fibrils and plaques has emerged as a central feature of the onset and progression of Alzheimer's disease, but the molecular pathways that control pathological aggregation have proved challenging to identify. Here, we use a combination of kinetic studies, selective radiolabeling expe

Each fall, eastern North American monarch butterflies in their northern range undergo a long-distance migration south to their overwintering grounds in Mexico. Migrants use a time-compensated sun compass to determine directionality during the migration. This compass system uses information extracted from sun-derived skylight cues that is compensated for time of day and ultimately transformed into

Background: Prostacyclin analogs are potent vasodilators and possess anti-inflammatory properties. However, the effect of prostacyclin on extracellular matrix (ECM) in COPD is not well known. Collagen fibrils and proteoglycans are essential ECM components in the lung and fibroblasts are key players in regulating the homeostasis of ECM proteins. The aim was to study the synthesis of prostacyclin an

In urban environments, airborne particles are continuously emitted, followed by atmospheric aging. Also, particles emitted elsewhere, transported by winds, contribute to the urban aerosol. We studied the effective density (mass-mobility relationship) and mixing state with respect to the density of particles in central Copenhagen, in wintertime. The results are related to particle origin, morpholog

The universally recognised action spectrum for the UV-induced conversion of 7-dehydrocholesterol to previtamin D3 in human skin was published in 1982, and indicates a maximum at about 297 nm with essentially no production above 315 nm. This work represents a milestone in research on vitamin D, but limitations in the original data should be recognised. Various findings have arisen in recent years w

Cross-sectional studies have shown an association between exposure to perfluoroalkyl substances (PFASs) and coronary heart disease (CHD). These findings need to be evaluated in longitudinal settings.

This article applies a global value-chain framework to the tobacco industry in Malawi, showing how cigarette manufacturers govern the chain and control first-tier suppliers, the leaf merchants. Contract farming offers smallholders the ability to meet manufacturers' compliance and traceability requirements and an opportunity for process and product upgrading, but threatens to exclude poorer growers

The main objective of the MCL3 study was to improve outcome for patients not in complete remission (CR) before transplant by adding 90 Y-ibritumomab-tiuxetan (Zevalin) to the high-dose regimen. One hundred sixty untreated, stage II-IV mantle cell lymphoma patients <66 years received rituximab (R)-maxi-CHOP (cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone) alternating with R-high

There is growing interest in how helpers working with severely traumatized individuals are affected by their work. A sample of 69 persons working with war and torture survivors across specialized centers throughout Sweden filled out questionnaires evaluating negative (i.e., compassion fatigue—composed of secondary traumatic stress [STS] and burnout—depersonalization, and impairment of functioning)

Objectives: Our aim was to elicit data representative of normal findings on 3-dimensional (3D) transvaginal gray-scale and power Doppler sonography of ovaries in women of fertile age. Methods: A total of 303 gynecologically asymptomatic white women 20 to 39 years old with spontaneous regular menstrual cycles were examined with transvaginal 3D gray-scale and power Doppler sonography on cycle days

Anastomosis of an acutely obstructed colon is associated with an increased risk of dehiscence. In experimental models, acute obstruction decreases collagen in the colonic wall, but the time course and propagation along the colon of the biochemical changes are unknown. Furthermore, there is a paucity of information on the correlation between these biochemical changes and histological features. Fort

In an interesting and thought-provoking paper recently published by the Economic History of Developing Regions, Johan Fourie and Leigh Gardner ask why relatively few papers from developing countries have been published in top-ranked economic history journals. They provide a number of tentative answers of which differences in academic traditions between regions seem to be an important one. In this

The neuropathological substrate of dementia in patients with Parkinson's disease is still under debate, particularly in patients with insufficient alternate neuropathology for other degenerative dementias. In patients with pure Lewy body Parkinson's disease, previous post-mortem studies have shown that dopaminergic and cholinergic regulatory projection systems degenerate, but the exact pathways th

The field of hypnosis anticipated the current interest in consciousness and has contributed in many ways to its conceptualization and research. This paper is divided into 3 sections. The first describes how hypnosis has enriched the study of alterations of consciousness, considered as dynamic processes subject to important individual differences. This section also considers how hypnosis offers an

The radiotherapy process is reviewed briefly and potential risks or pitfalls are identified. The focus is on modern advanced modalities in radiation therapy such as IMRT, VMAT, gating and tracking and also for the unknown to come. Existing methods, or quality controls (QC), or with better word barriers, are introduced at important steps of process with the purpose of prohibiting errors to continue

Electoral coordination has been a primary concern for scholars of African politics, interested in topics such as ethnic conflict mitigation and democratisation, for decades. However, understanding of micro-level electoral coordination in Sub-Saharan Africa is generally still very limited. This study is the first to investigate voter coordination in Sub-Saharan Africa using constituency-level elect