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Infrequent sporophyte production maintains a female-biased sex ratio in the unisexual clonal moss Hylocomium splendens

P>1. Sex ratios in unisexual bryophytes are most often female biased, whereas male-biased sex ratios predominate in unisexual seed plants. This 'bryophyte paradox', i.e. that sex ratios are biased in favour of the sex associated with the highest reproductive costs, has remained unexplained. 2. Analysis of sex-ratio patterns via the influence of sex distribution on population growth rates (lambda)

An array of highly flexible electrodes with a tailored configuration locked by gelatin during implantation-initial evaluation in cortex cerebri of awake rats.

A major challenge in the field of neural interfaces is to overcome the problem of poor stability of neuronal recordings, which impedes long-term studies of individual neurons in the brain. Conceivably, unstable recordings reflect relative movements between electrode and tissue. To address this challenge, we have developed a new ultra-flexible electrode array and evaluated its performance in awake

Charged-Particle Multiplicity Density at Midrapidity in Central Pb-Pb Collisions at root s(NN)=2.76 TeV

The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair root s(NN) = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 +/- 4(stat) +/- 76(syst), which corresponds to 8.3

Female Swedish backpackers in Vietnam: A hypotheses generating study on sexual health risks while travelling.

BACKGROUND: According to previous studies, foreign travellers and backpackers are at increased risk of sexually transmitted infections (STI). Concurrently, STI incidence, especially Chlamydia, is increasing among young Swedes. Our objective was to investigate Swedish backpackers' own view of sexual health and risks while travelling, with the purpose to identify hypotheses for further, more extensi

Semiconductor nanostructures enabled by aerosol technology

Aerosol technology provides efficient methods for producing nanoparticles with well-controlled composition and size distribution. This review provides an overview of methods and results obtained by using aerosol technology for producing nanostructures for a variety of applications in semiconductor physics and device technology. Examples are given from: production of metal and metal alloy particles

Direct ab initio study on the rate constants of radical C-2(A(3)Pi(u))+C3H8 reaction

The mechanism and kinetics of the radical C-3(2) + C3H8 reaction have been investigated theoretically by direct ab initio kinetics over a wide temperature range. The potential energy surfaces have been constructed at the CCSD(T)/B3//UMP2/B1 levels of theory. The electron transfer was also analyzed by quasi-restricted orbital (QRO) in detail. It was shown that all these channels proceed exclusively

Model predictive control of HCCI using variable valve actuation and fuel injection

Control of work output and combustion phasing on a Homogeneous Charge Compression Ignition (HCCI) engine is essential to realize the benefits of superior efficiency and emissions. This paper presents a model predictive control approach for cycle-by-cycle control of HCCI while respecting constraints on actuators that might exist on a production implementation. The strategy is based on a physical mo

Alcohol and drug use in groups of cannabis users: Results from a survey on drug use in the Swedish general population.

Although cannabis is well studied in the scientific literature, relatively little is known about the relationship between the frequency of cannabis use and the use of alcohol and other drugs. The aim of this study was to identify differences between frequent and occasional cannabis users with respect to the use of other illicit drugs, hazardous alcohol use, and unauthorized use of prescription dru

Exploring the limits of peak oil: naturalising the political, de-politicising energy

Peak oil has acquired prominence in the political lexicon of an increasing number of critical and radical perspectives during the ongoing ecological and economic crisis. By examining examples within academia as well as initiatives such as the Degrowth Movement and the Transition Network, this paper documents how a series of red-green discourses and movements mobilise the narrative of peak oil as a

Methods to Create a Longitudinal Integrated Demographic and Geographic Database on the Micro-Level: A Case Study of Five Swedish Rural Parishes, 1813–1914

The authors develop a methodology to create databases that can be used to add micro-level geographic context to longitudinal historical demographic analyses. The method transforms geographic objects as snapshots (digitized from historical maps) into temporal representations of longitudinal object lifelines and links individuals to these geographic objects. The methodology is evaluated via a case s

The prospects of cost reductions in willow production in Sweden

The current and future costs of willow short rotation coppice production in Sweden are analysed, considering all relevant cost factors explicitly. The future production costs are estimated considering effects of coppice area expansion and learning. The current and future costs of land and of risk premiums are subsequently estimated. Subsidies for farmers are not considered. If the area of willow c

Attention-deficit/hyperactivity disorder and risk for drug use disorder: a population-based follow-up and co-relative study.

Background. Although the association between attention-deficit/hyperactivity disorder (ADHD) and drug use disorder (DUD) is well documented, it is unclear whether it is causal or results from familial confounding. Method. In this study we included all 551 164 individuals born in Sweden between 1991 and 1995 and used linked data from multiple nationwide registries to identify those with ADHD prior

The European COPHES/DEMOCOPHES project: Towards transnational comparability and reliability of human biomonitoring results.

COPHES/DEMOCOPHES has its origins in the European Environment and Health Action Plan of 2004 to "develop a coherent approach on human biomonitoring (HBM) in Europe". Within this twin-project it was targeted to collect specimens from 120 mother-child-pairs in each of the 17 participating European countries. These specimens were investigated for six biomarkers (mercury in hair; creatinine, cotinine,

Magnetic Properties of [FeFe]-Hydrogenases: A Theoretical Investigation Based on Extended QM and QM/MM Models of the H-Cluster and Its Surroundings

In the present contribution, we report a theoretical investigation of the magnetic properties of the dihydrogen-evolving enzyme [FeFe]-hydrogenase, based on both DFT models of the active site (the H-cluster, a Fe6S6 assembly including a binuclear portion directly involved in substrates binding), and QM/MM models of the whole enzyme. Antiferromagnetic coupling within the H-cluster has been treated

The Significance of Emulation in the Oral Interaction Between Teacher and Students

The lack of attention to the role of emotions generally has led modern learning theories to neglect the importance of emulation as a pedagogical support to students’ learning. One reason could be that the influence of teacher personality is not considered in relation to learning outcome. Another reason may be that the concept of emulation has been used as a psychological conception for one-way tra

The Scandinavian Ice Sheet: from MIS 4 to the end of the Last Glacial Maximum

Glacial rebound modelling, to establish constraints on past ice sheets from the observational evidence of palaeo-shoreline elevations, is well established for the post- Last Glacial Maximum (post-LGM) period, for which the observational evidence is relatively abundant and well distributed spatially and in time. This is particularly the case for Scandinavia. For the earlier part of the glacial cycl

Bringing physics, synchrotron light and probing neutrons to the public: a collaborative outreach

Stanley Micklavzina, a US physics educator on sabbatical, teams up with a Swedish national research laboratory, a synchrotron radiation experimental group and a university science centre to develop and create educational and public outreach projects. Descriptions of the physics, science centre displays and public demonstrations covering the physics principles involved in using photons and neutrons

Anthropometric measures and epithelial ovarian cancer risk in the European Prospective Investigation into Cancer and Nutrition

We examined the associations of measured anthropometric factors, including general and central adiposity and height, with ovarian cancer risk. We also investigated these associations by menopausal status and for specific histological subtypes. Among 226,798 women in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, there were 611 incident cases of primary, malignant,

Towards an integrated global framework to assess the impacts of land use and management change on soil carbon : Current capability and future vision

Intergovernmental Panel on Climate Change (IPCC) Tier 1 methodologies commonly underpin project-scale carbon accounting for changes in land use and management and are used in frameworks for Life Cycle Assessment and carbon footprinting of food and energy crops. These methodologies were intended for use at large spatial scales. This can introduce error in predictions at finer spatial scales. There