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Effect of back reactions in the S-cycle on photosynthesis in very weak light

Photosynthesis in light which is so weak that excitation rates are comparable to the decay rates of S-states is modelled. It is found that oxygen evolution rate varies in a non-linear way with Photosystem II excitation rate in this region, but asymptotically approaches a linear relationship (with a slope of one oxygen molecule per four excitations) as excitation rate increases. The asymptote gives

Xenoestrogenic activity in blood of European and Inuit populations

BACKGROUND: Human exposure to persistent organic pollutants (POPs) is ubiquitous and found in all individuals. Studies have documented endocrine disrupting effects and impact on reproduction. The aim of the present study was to compare the level of xenoestrogenic activity in serum of groups with varying POP exposure, and to evaluate correlations to the POP biomarkers, 2,2',4,4',5,5'-hexachlorobiph

A 160MHz bipolar wideband IF amplifier

Wide-band intermediate-frequency (IF) amplifiers are needed when the data rates of communication systems increase. A single wide-band IF amplifier can also be used for a radio band with several narrow-band channels of varying strengths. High linearity is then required if intermodulation products are not to disturb weak channels. We have previously reported a highly linear wide-band IF amplifier in

Mobile Positioning in MIMO System Using Particle Filtering

Abstract—This paper represents the results of a simulation study on positioning of a mobile unit in MIMO settings. We used two different approaches for modeling the mobile movement, combined with a simple geometrical model for the MIMO channel. Three different particle filters were implemented for the position estimation. The results show that all three filters are able to achieve estimation accur

Reproductive isolation in temperate reef fishes

pportunity and recognition isolation can lead directly to reproductive isolation, the former via divergence in the location and timing of breeding, and the latter via differential mate preferences. We describe the potential significance of these factors in the maintenance of reproductive isolation in a clade of triplefin fishes that occur sympatrically around coastal New Zealand. Specifically, we

Comparative ecosystem - atmosphere exchange of energy and mass in a western Russian and a central Siberian bog. II) Interseasonal and interannual variability of CO2 fluxes

Net ecosystem–atmosphere exchange of CO2 (NEE) was measured in two boreal bogs during the snow-free periods of 1998, 1999 and 2000. The two sites were located in European Russia (Fyodorovskoye), and in central Siberia (Zotino). Climate at both sites was generally continental but with more extreme summer–winter gradients in temperature at the more eastern site Zotino. The snow-free period in Fyodor

Kärleksband i bunden form

In the 18th and 19th century the The Swedish Hymnbook was, besides the Almanac, one of the most well spread books in Sweden. Among the peasantry it was common to give decorated Hymnbook bindings as a gift at the moment of the engagement. This tradition made the bookbinders produce richly decorated retail bindings of parchment or leather suitable for the occasion. The decoration of these often simp

Epidemiological evidence on reproductive effects of persistent organochlorines in humans

Organochlorines are widespread pollutants in humans. Concern about adverse reproductive effects of these compounds arises from accidental exposure of humans and experimental studies. Recently, this issue has been addressed by a number of studies of exposed populations and hospital-based case-referent studies. These studies indicate that high concentrations of persistent organochlorines may adverse

Kriging with Nonparametric Variance Function Estimation

A method for fitting regression models to data that exhibit spatial correlation and heteroskedasticity is proposed. It is well known that ignoring a nonconstant variance does not bias least-squares estimates of regression parameters; thus, data analysts are easily lead to the false belief that moderate heteroskedasticity can generally be ignored. Unfortunately, ignoring nonconstant variance when f

Bibelsyn och frälsningslära i John Stotts teologi

This thesis is about the theology of the leader of Anglican evangelicalism, John Stott. Throughout this study of evangelical identity, the relationship between the objective belief and the subjective experience is a main thread. An attempt at definition of the Anglican evangelicalism: Theologically, evangelicalism means that the bibliology and the doctrine of salvation have been in the foreground

A New Barrier Function for IQC Optimization Problems

In this paper, we propose a new barrier function for optimization problems with Integral Quadratic Constraints (IQCs). The new barrier function is used to construct an interior point algorithm which solves IQC optimization problems in a more efficient fashion. Numerical tests as well as worst-case computational complexity analysis are performed to evaluate the efficiency of the proposed algorithm.

Workup for child neuropsychiatric disorders in adults often desirable - Functional disabilities can give rise to social maladjustment

So-called child neuropsychiatric disorders (ADHD/DAMP, autism spectrum disorders, Tourette's syndrome) are being recognized with increasing frequency in child and adolescent psychiatry. Through follow-up studies, case reports and autobiographical accounts it has become evident that these disorders often persist into adulthood, and the need for diagnostic evaluation of adults is increasing. The Neu