Search results

We investigated the influence of lake trophic status on accumulation of polychlorinated biphenyls (PCBs) in littoral and profundal invertebrates from 19 lakes in southern Sweden. The PCB concentration in profundal chironomids (Chironomus sp.) was negatively correlated with lake trophy but the concentration in littoral crayfish (Pacifasticus leniusculus) was unrelated to shifting nutrient regimes.

Research on the biology of the tumor stroma has the potential to lead to development of more effective treatment regimes enhancing the efficacy of drug-based treatment of solid malignancies. Tumor stroma is characterized by distorted blood vessels and activated connective tissue cells producing a collagen-rich matrix, which is accompanied by elevated interstitial fluid pressure (IFP), indicating a

Leukemic U-937 cells, which lack normal p53, were stably transfected with a temperature-sensitive mutant of p53 to investigate the consequences for growth and differentiation. On induction of wild-type p53 activity at the permissive temperature, some of these cells underwent maturation as judged by the capacity for oxidative burst and the appearance of monocyte related cell surface molecules. More

The dynamic rheological behaviour of Arracacha xanthorriza white carrot), Canna edulis (achira) and Oxalis tuberosa oca) starch gels were studied in strain-sweep mode. The starch was diluted with water to cover particle volume fractions of 1–3. The starch suspensions were heated at 89 8C for 30 min, and their swelling power and amylose leaching were measured. C. edulis showed the highest swelling

In the search for a triggering mechanism for the Paleocene-Eocene (P-E) boundary event, 55 Ma, centimeter-resolution chemical (e.g., Ir, Os, Pt) and isotope (e.g., (OS)-O-187/Os-188, He-3/He-4, Sr-87/Sr-86) records across this boundary have been established for six uplifted marine sections in Egypt, Spain and Denmark. The sections studied represent some of the stratigraphically most complete recor

In structural engineering the system effect is known as the possibility of transversal collaboration among parallel load-bearing elements due to mechanical load sharing. The statistical system effect, related to the variation of strength within structural timber elements, is investigated in this paper. The system investigated is a roof truss of W-type. The strength variation within and between tim

Incomplete taxon sampling has been a major problem in resolving the early divergences in birds. Five new mitochondrial genomes are reported here (brush-turkey, lyrebird, suboscine flycatcher, turkey vulture, and a gull) and three break up long branches that tended to attract the distant reptilian outgroup. These long branches were to galliforms, and to oscine and suboscine passeriformes. Breaking

With the growth of mobile computing, users will have simultaneous access to multiple overlaid networks, each with different characteristics, services and costs. This paper introduces TOMTEN (TOtal Management Of Transmissions for the ENd-user), a framework for managing resources in both this type of environment as well as the traditional single network environment. TOMTEN is a reactive framework th

The development of photodynamic therapy into a modality for treatment of prostate cancer calls for reliable optical dosimetry. We employ, for the first time, interstitial time-resolved spectroscopy to determine in vivo optical properties of human prostate tissue. Nine patients are included in the study, and measurements are conducted prior to primary brachytherapy treatment of prostate cancer. Int

A long-standing hypothesis posits that natural selection can favour two female strategies when density cycles. At low density, females producing many smaller progeny are favoured when the intrinsic rate of increase, r, governs population growth. At peak density, females producing fewer, high-quality, progeny are favoured when the carrying capacity, K, is exceeded and the population crashes. Here w

Arthrospira is one genus of cyanoprokaryota for which information on toxin production exists for only a few strains. The purpose of this study was to investigate whether strains of Arthrospira fusiformis produce intracellular toxic compounds such as microcystins and anatoxin-a. The study was based on three strains of Arthrospira, two strains isolated from wastewater ponds in Mozambique and one fro

Small-x evolution in QCD is conveniently described by Mueller's dipole model which, however, does not include saturation effects in a way consistent with boost invariance. In this paper we first show that the recently studied zero and one dimensional toy models exhibiting saturation and explicit boost invariance can be interpreted in terms positive definite k-> k+1 dipole vertices. Such k-> k+1 ve

Neutrophil granulocytes carry storage organelles, e.g., azurophil and specific granules. Poorly understood are the mechanisms for retrieval from constitutive secretion followed by sorting for storage. Therefore, we asked whether the specific granule protein human cathelicidin (hCAP-18) could be sorted for storage in other granules when the biosynthetic window is widened to allow this. We observed

Information about forest biodiversity has so far been collected mostly by using field inventories, but it is desirable to find other methods that can cover large areas at a lower cost. In a forest landscape covering 2000 ha in southern Sweden we tested if colour-infrared (CIR) aerial photographs on the scale of 1:30000 can be used to interpret forest stand characteristics correlated to the occurre

In this work, we present Monte Carlo simulations of mixtures containing negatively charged latex particles and positively charged dendrimers. We focus on the interaction between two latex particles as salt concentration, dendrimer dose, and generation number are varied. Interaction free energies and corresponding stability ratios are calculated. Minimal stability is found near the isoelectric poin

The etiology of Langerhans cell histiocytosis (LCH), a disease characterized by uncontrolled proliferation of Langerhans cells, is unknown. Although some believe that LCH is reactive, others support a neoplastic origin. We tested the hypothesis that LCH is neoplastic by investigating potential consistent chromosomal aberrations in LCH cells. We used multiparameter DNA flow cytometry to analyze the

Phylogenetic relationships and levels of geographic differentiation of two closely related bipolar taxa, Cladonia arbuscula and Cladonia mitis, were cladistically examined with ITS regions, SSU rDNA introns, partial P-tubulin, and partial glyceraldehyde 3-phosphate dehydrogenase (GAPDH) genes. In the combined analysis of the four genes, C arbuscula was paraphyletic, while C mitis, nested within C