Swedish University of Agricultural Sciences

About: Swedish University of Agricultural Sciences is a education organization based out in Uppsala, Sweden. It is known for research contribution in the topics: Population & Soil water. The organization has 13510 authors who have published 35241 publications receiving 1414458 citations. The organization is also known as: Sveriges Lantbruksuniversitet & SLU.

A single mutation affects both N-acetylglucosaminyltransferase and glucuronosyltransferase activities in a Chinese hamster ovary cell mutant defective in heparan sulfate biosynthesis.

Abstract: Mutants of Chinese hamster ovary cells have been found that no longer produce heparan sulfate. Characterization of one of the mutants, pgsD-677, showed that it lacks both N-acetylglucosaminyl- and glucuronosyltransferase, enzymes required for the polymerization of heparan sulfate chains. pgsD-677 also accumulates 3- to 4-fold more chondroitin sulfate than the wild type. Cell hybrids derived from pgsD-677 and wild type regained both transferase activities and the capacity to synthesize heparan sulfate. Two segregants from one of the hybrids reexpressed the dual enzyme deficiency, the lack of heparan sulfate synthesis, and the enhanced accumulation of chondroitin sulfate, suggesting that all of the traits were genetically linked. These findings indicate that the pgsD locus may represent a gene involved in the coordinate control of glycosaminoglycan formation.

Handbook of protocols for standardized measurement of terrestrial invertebrate functional traits

Abstract: Summary 1. Trait-based approaches are increasingly being used to test mechanisms underlying species assemblages and biotic interactions across a wide range of organisms including terrestrial arthropods and to investigate consequences for ecosystem processes. Such an approach relies on the standardized measurement of functional traits that can be applied across taxa and regions. Currently, however, unified methods of trait measurements are lacking for terrestrial arthropods and related macroinvertebrates (terrestrial invertebrates hereafter). 2. Here, we present a comprehensive review and detailed protocol for a set of 29 traits known to be sensitive to global stressors and to affect ecosystem processes and services. We give rec- ommendations how to measure these traits under standardized conditions across various ter- restrial invertebrate taxonomic groups. 3. We provide considerations and approaches that apply to almost all traits described, such as the selection of species and individuals needed for the measurements, the importance of intraspecific trait variability, how many populations or communities to sample and over which spatial scales. 4. The approaches outlined here provide a means to improve the reliability and predictive power of functional traits to explain community assembly, species diversity patterns and ecosystem processes and services within and across taxa and trophic levels, allowing compar- ison of studies and running meta-analyses across regions and ecosystems. 5. This handbook is a crucial first step towards standardizing trait methodology across the most studied terrestrial invertebrate groups, and the protocols are aimed to balance general applicability and requirements for special cases or particular taxa. Therefore, we envision this handbook as a common platform to which researchers can further provide methodological input for additional special cases.

Structure and function of cellular deoxyribonucleoside kinases.

Abstract: Deoxyribonucleoside kinases phosphorylate deoxyribonucleosides, a crucial reaction in biosynthesis of DNA precursors through the salvage pathway. Their medical interest stems from their activation of a number of anticancer and antiviral drugs such as 2-chloro-2'-deoxyadenosine, azidothymidine and acyclovir. Here we review what is presently known about each of the mammalian kinases as well as some other members of the deoxyribonucleoside kinase family. A description of the biochemical properties of the enzymes is followed by an overview of the structural studies made on this family of enzymes, including the catalytic mechanism as well as the mechanism for feedback inhibition. A presentation of homology models of other proteins in the family is made and, finally, the determinants of substrate and substrate analog specificities are described.

Impact of long-term nitrogen addition on carbon stocks in trees and soils in northern Europe

Abstract: The aim of this study was to quantify the effects of fertiliser N on C stocks in trees (stems, stumps, branches, needles, and coarse roots) and soils (organic layer +0–10 cm mineral soil) by analysing data from 15 long-term (14–30 years) experiments in Picea abies and Pinus sylvestris stands in Sweden and Finland. Low application rates (30–50 kg N ha−1 year−1) were always more efficient per unit of N than high application rates (50–200 kg N ha−1 year−1). Addition of a cumulative amount of N of 600–1800 kg N ha−1 resulted in a mean increase in tree and soil C stock of 25 and 11 kg (C sequestered) kg−1 (N added) (“N-use efficiency”), respectively. The corresponding estimates for NPK addition were 38 and 11 kg (C) kg−1 (N). N-use efficiency for C sequestration in trees strongly depended on soil N status and increased from close to zero at C/N 25 in the humus layer up to 40 kg (C) kg−1 (N) at C/N 35 and decreased again to about 20 kg (C) kg−1 (N) at C/N 50 when N only was added. In contrast, addition of NPK resulted in high (40–50 kg (C) kg−1 (N)) N-use efficiency also at N-rich (C/N 25) sites. The great difference in N-use efficiency between addition of NPK and N at N-rich sites reflects a limitation of P and K for tree growth at these sites. N-use efficiency for soil organic carbon (SOC) sequestration was, on average, 3–4 times lower than for tree C sequestration. However, SOC sequestration was about twice as high at P. abies as at P. sylvestris sites and averaged 13 and 7 kg (C) kg−1 (N), respectively. The strong relation between N-use efficiency and humus C/N ratio was used to evaluate the impact of N deposition on C sequestration. The data imply that the 10 kg N ha−1 year−1 higher deposition in southern Sweden than in northern Sweden for a whole century should have resulted in 2.0 ± 1.0 (95% confidence interval) kg m−2 more tree C and 1.3 ± 0.5 kg m−2 more SOC at P. abies sites in the south than in the north for a 100-year period. These estimates are consistent with differences between south and north in tree C and SOC found by other studies, and 70–80% of the difference in SOC can be explained by different N deposition.

Panarchy: Theory and Application

Abstract: The concept of panarchy provides a framework that characterizes complex systems of people and nature as dynamically organized and structured within and across scales of space and time. It has been more than a decade since the introduction of panarchy. Over this period, its invocation in peer-reviewed literature has been steadily increasing, but its use remains primarily descriptive and abstract. Here, we discuss the use of the concept in the literature to date, highlight where the concept may be useful, and discuss limitations to the broader applicability of panarchy theory for research in the ecological and social sciences. Finally, we forward a set of testable hypotheses to evaluate key propositions that follow from panarchy theory.