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Bioavailability of stream dissolved organic carbon (DOC) during spring flood and base flow in high-latitude streams

An important component of the carbon cycle is the lateral flow of dissolved organic carbon (DOC) from terrestrial ecosystems to streams and rivers. The fate of this carbon depends very much on the bioavailability of DOC (BDOC), which may determine whether DOC is returned to the atmosphere as CO2 or deposited in sediments. This study focuses on the linkages between stream DOC composition, optical c

Controllability in an islet specific regulatory network identifies the transcriptional factor NFATC4, which regulates Type 2 Diabetes associated genes

Probing the dynamic control features of biological networks represents a new frontier in capturing the dysregulated pathways in complex diseases. Here, using patient samples obtained from a pancreatic islet transplantation program, we constructed a tissue-specific gene regulatory network and used the control centrality (Cc) concept to identify the high control centrality (HiCc) pathways, which mig

Dissolved organic carbon (DOC) export from subarctic areas analyzed using a GIS/remote sensing approach

Subarctic ecosystems are predicted to experience the fastest responses to climate change on the planet, with dramatically altered vegetation patterns, frost dynamics and hydrological flow paths. The resulting change in dissolved organic carbon (DOC) export to river systems is poorly known, but reports of rising DOC in northern surface waters have led to widespread speculations on a possible climat

High variability in the decay of dissolved organic carbon from different boreal litter sources; a challenge to land-water carbon flux modeling

Dynamic ecosystem modelling offers potentially groundbreaking possibilities to reconstruct and project exports of Dissolved Organic Carbon (DOC) from land to surface water. However, the balance between production, degradation and export of soil DOC remains a challenge to model in boreal forests, partly because variability in soil DOC turnover is poorly understood. Here we determined the heterogene

An experimentalist's approach to global limnology: filling the gaps in process understanding of large-scale organic matter transformations (invited)

In the classical plenary lecture ‘Global limnology’ (J.A. Downing, 2007, SIL in Montréal), a new holistic direction for freshwater science was pointed out, focused at upscaling of limnological processes to planet Earth. Since then, the literature on the global importance of freshwater networks, especially as routes for carbon degassing, burial and transport, has grown explosively. This has been re

Photo-reactivity (apparent quantum yield) of dissolved organic carbon during the freshwater transit from land to sea

In spite of substantial greenhouse gas emissions from photo-degradation of dissolved organic carbon (DOC), little is known about the variability in DOC photo-reactivity. It has been suggested that photo-reactivity depends on the degree of DOC pigmentation. However, recent evidence suggests that also non-colored fractions can be photo-reactive. Furthermore photo-degradation processes interact with

Terrestrial support of zooplankton biomass in northern rivers (invited)

The contribution of terrestrially-derived carbon to micro-crustacean zooplankton biomass (i.e. allochthony) has been previously studied in lakes and reservoirs, but little is known about allochthony in rivers. We hypothesized that restricted selective grazing in turbulent environments such as rivers would decouple zooplankton from specific microbial and algal food resources, such that their alloch

Mapping conservation priorities in alpine and subartctic Swedish lakes affected by rapid climate change

Swedish alpine and subarctic areas undergo rapid transitions due to climate change, especially in relatively humid areas where the forest vegetation is expanding. It has been suggested that lakes in these areas are in transition from clearwater into brownwater state, because of the humus layer building up in surrounding soils, with negative consequences, e.g., for the biomass production of zooplan

In situ plankton community respiration measurements show low respiratory quotients in a eutrophic lake

Planktonic community respiration is an important carbon cycling process, typically quantified by converting measured values of dissolved oxygen consumption rates into carbondioxide production rates using a respiratory quotient of 1 (RQ = carbondioxide per oxygen by moles). However, the true variability in planktonic RQs between different aquatic ecosystems is poorly understood. We conducted in sit

Different boreal terrestrial DOC sources show different δ13C signatures: implications for tracing labile doc across the land-water interface

The stable carbon isotope ratio (δ13C) is a key tool in tracing the source of carbon within and across ecosystems. In isotope mixing models dissolved organic carbon (DOC) from terrestrial sources is often assigned a fixed δ13C of roughly -28‰ to -27‰ in C3 plant-dominated areas. However, the claim of a uniform δ13C distribution for terrestrial DOC sources of different reactivity has seldom been te

Regional competition, business politicians, and subnational fiscal policy

What explains subnational policy choices over tax cut after decentralization? We test two different explanations in the context of the 2002 tax reform in Russia. A popular strand of literature suggests that decentralization induces more regional competition over investment, motivating subnational tax cuts. A second body of literature suggests that personal business interests of regional governors

Lévy-stable two-pion Bose-Einstein correlations in s NN =200 GeV Au+Au collisions

We present a detailed measurement of charged two-pion correlation functions in 0-30% centrality sNN=200 GeV Au+Au collisions by the PHENIX experiment at the Relativistic Heavy Ion Collider. The data are well described by Bose-Einstein correlation functions stemming from Lévy-stable source distributions. Using a fine transverse momentum binning, we extract the correlation strength parameter λ, the

Open Notes in Swedish Psychiatric Care (Part 2) : Survey Among Psychiatric Care Professionals

Background: This is the second of two papers presenting the results from a study of the implementation of patient online access to their electronic health records (here referred to as Open Notes) in adult psychiatric care in Sweden. The study contributes an important understanding of both the expectations and concerns that existed among health care professionals before the introduction of the Open

Test of Responsiveness and Sensitivity of the Questionnaire "lymphedema Quality of Life Inventory"

Background: Lymphedema may affect patients' health-related quality of life (HRQoL) and thus a disease-specific questionnaire is needed. The Lymphedema Quality of life Inventory (LyQLI) has been tested for reliability and validity. The purpose of this study was to test the LyQLI for responsiveness and sensitivity. Methods and Results: The study participants were patients with lymphedema in the uppe

Astrometry and exoplanets in the Gaia era : A Bayesian approach to detection and parameter recovery

The Gaia mission is expected to make a significant contribution to the knowledge of exoplanet systems, both in terms of their number and of their physical properties. We develop Bayesian methods and detection criteria for orbital fitting, and revise the detectability of exoplanets in light of the in-flight properties of Gaia. Limiting ourselves to one-planet systems as a first step of the developm

Coding variants in NOD-like receptors : An association study on risk and survival of colorectal cancer

Nod-like receptors (NLRs) are important innate pattern recognition receptors and regulators of inflammation or play a role during development. We systematically analysed 41 non-synonymous single nucleotide polymorphisms (SNPs) in 21 NLR genes in a Czech discovery cohort of sporadic colorectal cancer (CRC) (1237 cases, 787 controls) for their association with CRC risk and survival. Five SNPs were f