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Optimal design of plate heat exchangers with and without pressure drop specifications

The traditional design method for plate heat exchangers(PHEs), either epsilon-number of transfer units (epsilon-NTU) or logarithmic mean temperature difference method, involves many trials in order to meet the pressure drop constraints. This can be avoided through the developed design method, which takes the full utilization of the allowable pressure drops as a design objective. The proposed metho

Daily physical activity and its relation to aerobic fitness in children aged 8-11 years.

A positive relationship between daily physical activity and aerobic fitness exists in adults. Studies in children have given conflicting results, possibly because of differences in methods used to assess daily physical activity and fitness. No study regarding daily physical activity and fitness in children has been published, where fitness has been assessed by direct measurement of maximum oxygen

Ice-dammed lakes and rerouting of the drainage of northern Eurasia during the Last Glaciation

During the Quaternary period, ice sheets centred over the Barents and Kara seas expanded several times onto mainland Russia and blocked northflowing rivers, such as the Yenissei, Ob, Pechora and Mezen. Large ice-dammed lakes with reversed outlets, e.g. toward the Caspian Sea, formed south of these ice sheets. Some lakes are reconstructed from shorelines and lacustrine sediments, others mainly from

Seasonal denitrification potential in wetland sediments with organic matter from different plant species

Vegetation both physically and biochemically influences denitrification in wetlands. Litter from various plant species supplies various amounts and qualities of organic carbon to denitrifying bacteria, and may thus affect denitrification capacity. We explore whether there is seasonal variation in the denitrification potential in stands of Glyceria maxima, Phragmites australis, Typha latifolia, and

Selective etching of III-V nanowires for molecular junctions

Selective etching of heterostructure III-V nanowires can be used to form tips and narrow gaps simultaneously on multiple nanowires on a single wafer. In this study we tested bromine based etching of gallium arsenide segments in gallium phosphide nanowires. Depending on the etchant and etching conditions, a variety of gap topologies and tip-like structures were observed. The method is compatible wi

Mate choice, male condition-dependent ornamentation and MHC in the pheasant

The Hamilton and Zuk model predicts that genes for resistance to various pathogens may be continuously heritable due to selection disequilibria caused by coadaptional cycles of hosts and pathogens. The model further suggests that the expression of male secondary ornaments is condition-dependent and that only individuals with superior genetic disease resistance and vigour can fully express exaggera

Holocene organic carbon burial rates in the Baltic coast

To estimate Holocene changes in organic carbon mass accumulation rates (Corg MARs) in the southeastern Swedish Baltic Sea, two sediment cores were studied in combination with biogeochemical modelling. Prior to 11 300 cal. BP, Corg MARs were extremely low, indicating low organic matter production on the catchment of the Baltic Ice Lake. Following a brief regression, the Ancylus Lake stage occurred

Performance of the projectile fragmentation wall at CELSIUS storage ring

The projectile fragmentation wall [Budzanowski, A. et al., Nucl. Instr. Meth. A482, 528 (2002).] (PFW) is a part of it bigger detection system comprising of the CHICSi detector [Jakobsson, B., Nucl. Phys. News Int. 9:2 22 (1999). Siwek, A., Nucl. Phys., A654, 2695 (1999)] and a recoil detectors array [Kuznetsov, A. V. et al, Nucl. Instr. Meth. A452, 525 (2000)]. The system is designed to register

Progress in miniaturisation of proteon arrays - a step closer to high-density nanoarrays

Protein microarrays is a technology with great promise for high-throughput proteomics. Designing high-performance protein microarrays for global proteome analysis has, however, turned out to be challenging. To this end, major efforts are under way to design novel array formats capable of harboring the tremendous range of probes required to target complex proteomes composed of more than 10 000 anal

Climacteric medicine: European Menopause and Andropause Society (EMAS) 2004/2005 position statements on peri- and postmenopausal hormone replacement therapy

In women experiencing distressing climacteric symptoms during the peri- and postmenopause there is conclusive evidence from abundant randomised controlled trials that systemic hormone replacement therapy (HRT) of any type affords symptom relief, with no alternative treatment producing similar effect. Though this evidence is accumulating, the question of how to provide best clinical practice in an

VHY, a novel myristoylated testis-restricted dual specificity protein phosphatase related to VHX

The human DUSP15 gene encodes an uncharacterized 235-amino acid member of the subfamily of small dual specificity protein phosphatases related to the Vaccinia virus VH1 phosphatase. Similar to VHR-related MKPX (VHX) (DUSP22), the predicted protein has an N-terminal myristoylation recognition sequence, and we show here that both are indeed modified by the attachment of a myristate to Gly-2. In reco

Acute leukaemia or highly malignant lymphoma patients' quality of life over two years: a pilot study

The aim of this study was, first, to investigate the quality of life and sense of coherence for acute leukaemia and malignant lymphoma patients at the start of treatment and over 2 years. A second aim was to compare questionnaire responses with patients' statements in open-ended interviews. A consecutive sample of 16 patients responded to the Quality of Life Questionnaire (QLQ-C30), Lund Gerontolo

Phosphorus limitation of bacterial growth in high Arctic lakes and ponds

Water from lakes and tundra ponds on Banks, Melville, Ellef-Ringnes, Ellesmere and Devon Island (74 - 79 degreesN, 82 - 116 degreesW) in the Canadian high Arctic was studied in batch culture experiments to test whether nitrogen, phosphorus or organic carbon limited bacterial growth and biomass accumulation. Water samples containing indigenous bacteria were amended with carbon ( glucose), nitrogen

A new approach for predicting the extreme response of structures

In this article a method to estimate the mean upcrossing intensity, mu(u), of a stochastic process is proposed. It is assumed that the stochastic process is a sum of a Gaussian process and a second-order correction term. The method is based on the two-dimensional Saddlepoint approximation. The accuracy of the method is tested on processes having analytical solutions for mu(u). Numerical examples a

Phylogeography of the common vole (Microtus arvalis) with particular emphasis on the colonization of the Orkney archipelago

To investigate the human introduction of the common vole Microtus arvalis onto the Orkney islands, the complete cytochrome b gene was sequenced in 41 specimens from both Orkney (four localities) and elsewhere in their range (26 localities). Orkney voles belonged to the same phylogenetic lineage, 'Western', as individuals from France and Spain indicating southwestern Europe as the most likely sourc

Monitor – Biology

The hottest developments in the fields of cancer research, neuroscience, genomics and proteomics, anti-virals and more, with a pick of the key research papers in these areas.

Impact of drying and re-wetting on N, P and K dynamics in a wetland soil

As increased nutrient availability due to drainage is considered a major cause of eutrophication in wetlands rewetting of drained wetlands is recommended as a restoration measure. The effect of soil drying and rewetting on the contribution of various nutrient release or transformation processes to changed nutrient availability for plants is however weakly understood. We measured effects of soil dr