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Numerical modelling of P/M steel bars subjected to fatigue loading using an extended Gurson model

The possibility of modelling experiments conducted on P/M steel bars subjected to strain controlled fatigue loading is investigated. The constitutive relation is an extended Gurson model, using a viscoplastic formulation with plasticity driven damage accumulation supplemented by kinematic as we'll as isotropic hardening. The total damage is modelled as the sum of void growth and void nucleation. P

The use of AFLP to find an informative SNP: genetic differences across a migratory divide in willow warblers

We used the amplified fragment length polymorphism (AFLP) method to obtain genetic markers distinguishing two subspecies of willow warblers Phylloscopus trochilus that have different migratory behaviours but are not differentiated in mitochondrial DNA or at several microsatellite loci. With the inverse-polymerase chain reaction (PCR) approach we converted a dominant AFLP-marker to a codominant sin

58Ni: An Unpaired Band Crossing at New Heights of Angular Momentum for Rotating Nuclei

High-spin states in Ni-58 have been investigated by means of the fusion-evaporation reaction Si-28(S-32,2p)Ni-58 at 130 MeV beam energy. Discrete-energy levels are observed in Ni-58 at record-breaking 42 MeV excitation energy and angular momenta in excess of 30h. The states form regular rotational bands with unprecedented high rotational frequencies. A comparison with configuration dependent crank

Above- and below-ground net primary productivity across ten Amazonian forests on contrasting soils

The net primary productivity (NPP) of tropical forests is one of the most important and least quantified components of the global carbon cycle. Most relevant studies have focused particularly on the quantification of the above-ground coarse wood productivity, and little is known about the carbon fluxes involved in other elements of the NPP, the partitioning of total NPP between its above- and belo

Hydroxyl radical consumption following photolysis of vapor-phase hydrogen peroxide at 266 nm: Implications for photofragmentation laser-induced fluorescence measurements of hydrogen peroxide

The decay of OH concentration following photolysis of room-temperature vapor-phase hydrogen peroxide is studied as a function of photolysis fluence at 266 nm in an open air environment. The rate of decay is found to increase with increasing photolysis fluence, i.e., with increasing number of photodissociated H2O2(g) molecules. Single-exponential functions approximate the OH concentration decay rat

Influence of activated charcoal, porcine gastric mucin and beta-cyclodextrin on the morphology and growth of intestinal and gastric Helicobacter spp.

Bile-tolerant Helicobacter spp. are emerging human and animal pathogens. However, due to their fastidious nature, which requires nutrient-rich complex media to grow, infection with these bacteria may be underestimated. The accumulation of toxic metabolites in cultures may be one of the main obstacles for successful culture of these organisms. The present study examined various potential growth-enh

Bias and temperature dependence of the escape processes in quantum dots-in-a-well infrared photodetectors

The performance of quantum dots-in-a-well infrared photodetectors (DWELL IPs) has been studied by means of interband and intersubband photocurrent measurements as well as dark current measurements. Using interband photocurrent measurements, substantial escape of electrons from lower lying states in the DWELL structure at large biases was revealed. Furthermore, a significant variation in the escape

Molecular imaging with endogenous substances

Dynamic nuclear polarization has enabled hyperpolarization of nuclei such as C-13 and N-15 in endogenous substances. The resulting high nuclear polarization makes it possible to perform subsecond C-13 MRI. By using the dynamic nuclear polarization hyperpolarization technique, 10% polarization was obtained in an aqueous solution of 100 mM C-13-labeled urea, ready for injection. The in vivo T, relax

The application of CD antigen proteomics to pharmacogenomics

The advent of multiplexing technologies has raised the possibility that disease states can be defined using discrete genomic and proteomic patterns or signatures. However this emerging area has been limited by the 'content problem', arising from the uncertainty of which molecules to focus on. The human cluster of differentiation (CD) antigens are expressed on cells of the human immune system (leuk

Low expression of interferon regulatory factor-1 and identification of novel exons skipping in patients with chronic myeloid leukaemia

Chronic myeloid leukaemia (CML) is a malignant clonal disorder of the haematopoietic stem cell. Treatment of CML patients with interferon alpha (IFN-alpha) has induced haematological and cytogenetic remission. Interferons transcriptionally activate target genes through the JAK-STAT and interferon regulated factors (IRFs) family pathways. Interferon regulated factor-1 (IRF-1) is a transcriptional a

Sperm DNA damage in men from infertile couples

Aim: To investigate the prevalence of high levels of sperm DNA damage among men from infertile couples with both normal and abnormal standard semen parameters. Methods: A total of 350 men from infertile couples were assessed. Standard semen analysis and sperm chromatin structure assay (SCSA) were carried out. Results: Ninety-seven men (28% of the whole study group) had a DNA fragmentation index (D

Tolerance (PICT) of the bacterial communities to copper in vineyards soils from Spain

To detect effects of Cu pollution, the Cu tolerance of soil bacterial communities extracted from several vineyards located in NW Spain was measured. Bacterial community tolerance was estimated by means of the thymidine (TdR) and leucine (Leu) incorporation techniques using either IC50 values (the log of the metal concentration that reduced incorporation to 50%) or the percentage of activity at one

How does breeding system variation modulate sexual antagonism?

The study of sexually antagonistic (SA) traits remains largely limited to dioecious (separate sex), mobile animals. However, the occurrence of sexual conflict is restricted neither by breeding system (the mode of sexual reproduction, e. g. dioecy or hermaphroditism) nor by sessility. Here, we synthesize how variation in breeding system can affect the evolution and expression of intra- and inter-lo

Adaptation and the poor: development, resilience and transition

Risk minimization is no longer a sufficient survival strategy for poor people in livelihood systems increasingly exposed to frequent extreme events. This calls for comprehensive adaptation to climate change. Within the climate change regime, adaptation is as central as mitigation but needs to be much more explicitly addressed at local, national and global levels. There is also a need for policy re

Transposition of the great arteries, pulmonary atresia, and multiple ventricular septal defects associated with multiple cardiac rhabdomyomas in a case of tuberous sclerosis

Multiple cardiac rhabdomyomas are frequently associated with tuberous sclerosis. However, very few cardiac malformations have been described with tuberous sclerosis. We report an unusual case of tuberous sclerosis with cerebral and renal lesions associated with dextrotransposition of the great arteries, pulmonary atresia, patent ductus arteriosus, multiple ventricular septal defects, and parachute