| 1. |
- Menzel, Carolin, et al.
(author)
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Improved material properties of solution-cast starch films : Effect of varying amylopectin structure and amylose content of starch from genetically modified potatoes
- 2015
-
In: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 130, s. 388-397
-
Journal article (peer-reviewed)abstract
- High-amylose potato starches were produced through genetic modification resulting in changed granule morphology and composition, with higher amylose content and increased chain length of amylopectin. The increased amylose content and structural changes in amylopectin enhanced film-forming behavior and improved barrier and tensile properties in starch films. The molecular structure in these starches was related to film-forming properties. Solution-cast films of high-amylose starch revealed a homogeneous structure with increasing surface roughness at higher amylose content, possibly due to amylose aggregation. Films exhibited significantly higher stress and strain at break compared with films of wild-type starch, which could be attributable to the longer chains of amylopectin being involved in the interconnected network and more interaction between chains, as shown using transmission electron microscopy. The oxygen permeability of high-amylose starch films was significantly decreased compared with wild-type starch. The nature of the modified starches makes them an interesting candidate for replacement of non-renewable oxygen and grease barrier polymers used today.
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| 2. |
- Soltani, Soheil, 1984, et al.
(author)
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CFD Characerization of Monolithic Reactors for Kinetic Studies
- 2014
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In: Canadian Journal of Chemical Engineering. - : Wiley. - 1939-019X .- 0008-4034. ; 92:9, s. 1570-1578
-
Journal article (peer-reviewed)abstract
- A laboratory reactor for kinetic studies has been simulated using computational fluid dynamics (CFD). Analysis of temperature distribution within the system shows that adding an inert monolith upstream the catalyst enhances heat conduction and therefore significantly reduces radial temperature gradients. Adjustment of the heating coil plays an important role as well by allowing the gas phase to smooth out the radial temperature profile. Radiative heat transfer and its effects on both the heat losses from the catalyst and on the measurements with an unprotected thermocouple have been particularly investigated. In order to prevent both the falsifying effect of radiation and the influences from the ongoing reaction, thermocouples should be placed and shielded inside a clogged channel. An inert monolith that is placed downstream the catalyst effectively serves as a radiation shield and drastically reduces both axial and radial gradients. Studies of the dispersion in the system reveal that the FTIR's gas cell is the most important source of the overall broadening in the concentration signal, with the reactor tube being the next major source of the distortion. An algorithm based on the Tikhonov regularization method has been developed for calculating the deconvolution of the concentration data, which has refined the time-resolution in transient experiments from 20 to 2 s.
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| 3. |
- Alsmark, Cecilia M., et al.
(author)
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The louse-borne human pathogen Bartonella quintana is a genomic derivative of the zoonotic agent Bartonella henselae
- 2004
-
In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 101:26, s. 9716-9721
-
Journal article (peer-reviewed)abstract
- We present the complete genomes of two human pathogens, Bartonella quintana (1,581,384 bp) and Bartonella henselae (1,931,047 bp). The two pathogens maintain several similarities in being transmitted by insect vectors, using mammalian reservoirs, infecting similar cell types (endothelial cells and erythrocytes) and causing vasculoproliferative changes in immunocompromised hosts. A primary difference between the two pathogens is their reservoir ecology. Whereas B. quintana is a specialist, using only the human as a reservoir, B. henselae is more promiscuous and is frequently isolated from both cats and humans. Genome comparison elucidated a high degree of overall similarity with major differences being B. henselae specific genomic islands coding for filamentous hemagglutinin, and evidence of extensive genome reduction in B. quintana, reminiscent of that found in Rickettsia prowazekii. Both genomes are reduced versions of chromosome I from the highly related pathogen Brucella melitensis. Flanked by two rRNA operons is a segment with similarity to genes located on chromosome II of B. melitensis, suggesting that it was acquired by integration of megareplicon DNA in a common ancestor of the two Bartonella species. Comparisons of the vector-host ecology of these organisms suggest that the utilization of host-restricted vectors is associated with accelerated rates of genome degradation and may explain why human pathogens transmitted by specialist vectors are outnumbered by zoonotic agents, which use vectors of broad host ranges.
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| 4. |
- Andersson, Andreas, 1980-, et al.
(author)
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Pilot testing of a hydraulic bridge exciter
- 2015
-
In: EVACES'15, 6th International Conference on Experimental Vibration Analysis For Civil Engineering Structures. - Zurich : EDP Sciences. ; , s. 02001-
-
Conference paper (peer-reviewed)abstract
- This paper describes the development of a hydraulic bridge exciter and its first pilot testing on a full scale railway bridge in service. The exciter is based on a hydraulic load cylinder with a capacity of 50 kN and is intended for controlled dynamic loading up to at least 50 Hz. The load is applied from underneath the bridge, enabling testing while the railway line is in service. The system is shown to produce constant load amplitude even at resonance. The exciter is used to experimentally determine frequency response functions at all sensor locations, which serve as valuable input for model updating and verification. An FE-model of the case study bridge has been developed that is in good agreement with the experimental results.
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| 5. |
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| 6. |
- Andersson, Johanna, et al.
(author)
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Comparison of steaming and boiling of root vegetables for enhancing carbohydrate content and sensory profile
- 2022
-
In: Journal of Food Engineering. - : Elsevier BV. - 0260-8774 .- 1873-5770. ; 312
-
Journal article (peer-reviewed)abstract
- Root vegetables have unique techno-functional and nutritional properties however, their use in processed foods is limited to a few species, partially due to a lack of knowledge related to the impact of thermal treatments on the sensory properties. This study investigated the effect of steaming and boiling on the microstructure, mechanical properties, and sensory profile of three model root vegetables with distinct carbohydrate composition: Jerusalem artichoke (Helianthus tuberosus L.), parsnip (Pastinaca sativa), and beetroot (Beta vulgaris). Thermally treated Jerusalem artichoke and parsnip showed higher content of cell wall polysaccharides, particularly β-glucans (e.g. cellulose) and pectic components, compared to raw. Steaming produced more cell shrinkage and loss of cell-cell adhesion than boiling, leading to softer vegetables. Processed beetroot showed loss of cell turgor and drastic softening but not clear changes in overall carbohydrate content. The scores for several flavour and in-mouth attributes were higher for steamed vegetables compared to boiled. Our results give insights on the processability of root vegetables towards products with enhanced sensory and nutritional properties.
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| 7. |
- Andersson, Jakob, 1974-, et al.
(author)
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Geomapping Landscapes of Writing (GLoW) : Large-Scale Spatial Analysis of the Cuneiform Corpus (c. 3400 BCE to 100 CE)
- 2021
-
Conference paper (other academic/artistic)abstract
- The cuneiform record ranks among the largest preserved bodies of historical documentation from the ancient world (Streck 2010). Conveyed on omnipresent and extremely durable types of material, cuneiform texts are preserved in immense, extending over all of the Middle East and a historical period of more than three millennia of early human history. Drawing on recent advances in digital humanities and geospatial data mapping, GLoW aims to survey, analyse, and investigate broader, macrohistorical patterns in the formation and preservation of this unique historical record. As a first quantifiable, comprehensive study of the cuneiform corpus, GLoW will provide a benchmark example of the application of digital and spatial computing tools to the study of writing in early human history. This poster offers an introduction to key research foci and the project research programme, including an introduction to data infrastructure, dissemination, and key collaborators.
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| 8. |
- Andersson, Siv G E, et al.
(author)
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Comparative genomics of microbial pathogens and symbionts.
- 2002
-
In: Bioinformatics. - 1367-4803 .- 1367-4811. ; 18 Suppl 2, s. S17-
-
Journal article (peer-reviewed)abstract
- We are interested in quantifying the contribution of gene acquisition, loss, expansion and rearrangements to the evolution of microbial genomes. Here, we discuss factors influencing microbial genome divergence based on pair-wise genome comparisons of closely related strains and species with different lifestyles. A particular focus is on intracellular pathogens and symbionts of the genera Rickettsia, Bartonella and BUCHNERA: Extensive gene loss and restricted access to phage and plasmid pools may provide an explanation for why single host pathogens are normally less successful than multihost pathogens. We note that species-specific genes tend to be shorter than orthologous genes, suggesting that a fraction of these may represent fossil-orfs, as also supported by multiple sequence alignments among species. The results of our genome comparisons are placed in the context of phylogenomic analyses of alpha and gamma proteobacteria. We highlight artefacts caused by different rates and patterns of mutations, suggesting that atypical phylogenetic placements can not a priori be taken as evidence for horizontal gene transfer events. The flexibility in genome structure among free-living microbes contrasts with the extreme stability observed for the small genomes of aphid endosymbionts, in which no rearrangements or inflow of genetic material have occurred during the past 50 millions years (1). Taken together, the results suggest that genomic stability correlate with the content of repeated sequences and mobile genetic elements, and thereby indirectly with bacterial lifestyles.
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| 9. |
- Baghdadchi, Amir, 1994-, et al.
(author)
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Corrosion resistance and microstructure analysis of additively manufactured 22% chromium duplex stainless steel by laser metal deposition with wire
- 2023
-
In: Journal of Materials Research and Technology. - 2238-7854 .- 2214-0697. ; 26, s. 6741-6756
-
Journal article (peer-reviewed)abstract
- Microstructure characteristics and pitting corrosion of a duplex stainless steel (DSS) manufactured by laser metal deposition with wire (LMDw) were studied. The layer-by-layer LMDw process resulted in a mixed microstructure of predominantly ferrite with 2% austenite and chromium-rich nitrides, and reheated regions with ~33% austenite. The high cooling rate of LMDw restricted the distribution of Cr, Mo, and Ni, in ferrite and austenite, while N diffuses from ferrite to austenite. Subsequent heat treatment at 1100 C for 1 h resulted in homogenized microstructure, dissolution of nitrides, and balanced ferrite/austenite ratio. It also led to the redistribution of Cr and Mo to ferrite, and Ni and N to austenite. At room temperature, cyclic potentiodynamic polarization measurements in 1.0 M NaCl solution showed no significant differences in corrosion resistance between the as-deposited and heat-treated samples, despite the differences in terms of ferrite to austenite ratio and elemental distribution. Critical pitting temperature (CPT) was the lowest (60 C) for the predominantly ferritic microstructure with finely dispersed chromium-rich nitrides; while reheated area with ~33% austenite in as-deposited condition achieved higher critical temperature comparable to what was obtained after heat treatment (73 and 68 C, respectively). At temperatures above the CPT, selective dissolution of the ferrite after deposition was observed due to depletion of N, while after heat treatment, austenite preferentially dissolved due to Cr and Mo concentrating in ferrite. In summary, results demonstrate how microstructural differences in terms of ferrite-to-austenite ratio, distribution of corrosion-resistant elements, and presence of nitrides affect corrosion resistance of LMDw DSS.
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| 10. |
- Berglund, Eva C., et al.
(author)
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Run-off replication of host-adaptability genes is associated with gene transfer agents in the genome of mouse-infecting Bartonella grahamii
- 2009
-
In: PLoS genetics. - : Public Library of Science (PLoS). - 1553-7404. ; 5:7, s. e1000546-
-
Journal article (peer-reviewed)abstract
- The genus Bartonella comprises facultative intracellular bacteria adapted to mammals, including previously recognized and emerging human pathogens. We report the 2,341,328 bp genome sequence of Bartonella grahamii, one of the most prevalent Bartonella species in wild rodents. Comparative genomics revealed that rodent-associated Bartonella species have higher copy numbers of genes for putative host-adaptability factors than the related human-specific pathogens. Many of these gene clusters are located in a highly dynamic region of 461 kb. Using hybridization to a microarray designed for the B. grahamii genome, we observed a massive, putatively phage-derived run-off replication of this region. We also identified a novel gene transfer agent, which packages the bacterial genome, with an over-representation of the amplified DNA, in 14 kb pieces. This is the first observation associating the products of run-off replication with a gene transfer agent. Because of the high concentration of gene clusters for host-adaptation proteins in the amplified region, and since the genes encoding the gene transfer agent and the phage origin are well conserved in Bartonella, we hypothesize that these systems are driven by selection. We propose that the coupling of run-off replication with gene transfer agents promotes diversification and rapid spread of host-adaptability factors, facilitating host shifts in Bartonella.
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| 11. |
- Boussau, Bastien, et al.
(author)
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Computational inference of scenarios for alpha-proteobecterial genome evolution
- 2004
-
In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 101:26, s. 9722-9727
-
Journal article (peer-reviewed)abstract
- The alpha-proteobacteria, from which mitochondria are thought to have originated, display a 10-fold genome size variation and provide an excellent model system for studies of genome size evolution in bacteria. Here, we use computational approaches to infer ancestral gene sets and to quantify the flux of genes along the branches of the alpha-proteobacterial species tree. Our study reveals massive gene expansions at branches diversifying plant-associated bacteria and extreme losses at branches separating intracellular bacteria of animals and humans. Alterations in gene numbers have mostly affected functional categories associated with regulation, transport, and small-molecule metabolism, many of which are encoded by paralogous gene families located on auxiliary chromosomes. The results suggest that the alpha-proteobacterial ancestor contained 3,000-5,000 genes and was a free-living, aerobic, and motile bacterium with pili and surface proteins for host cell and environmental interactions. Approximately one third of the ancestral gene set has no homologs among the eukaryotes. More than 40% of the genes without eukaryotic counterparts encode proteins that are conserved among the alpha-proteobacteria but for which no function has yet been identified. These genes that never made it into the eukaryotes but are widely distributed in bacteria may represent bacterial drug targets and should be prime candidates for future functional characterization.
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| 12. |
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| 13. |
- Ericsson, Per, et al.
(author)
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Characterization of particulate emissions and methodology for oxidation of particulates from non-diesel combustion systems
- 2008
-
In: SAE Technical Paper. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191.
-
Journal article (peer-reviewed)abstract
- Tailpipe particulate emissions, i.e., particle number, size distribution and total mass, from a series of four-cylinder engines with 2L displacement and power output of approximately 150 hp have been measured. The engines were in their respective vehicle installation, all midsize vehicles from various manufacturers, and represented different combustion concepts, i.e., port- and direct-injected vehicles and E5 and E85 fuels. The results are compared to post-Euro V emission standards for gasoline and biofuels using diesel as reference. The results show that the type of combustion and fuel significantly affect the particulate formation. In general, direct-injected engines show high particle numbers and mass compared to port-injected engines. The particulate number and total mass can be reduced by using biofuels, e.g., ethanol mixes, instead of gasoline. Moreover, an experimental procedure and setup facilitating precise studies of oxidation of particulates in realistic filter structures by well-controlled gas flow (composition and temperature) and sample (particulate load and temperature) conditions has been developed. The results from this method have been verified by using commercial soot as reference.
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| 14. |
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| 15. |
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| 16. |
- Frank, A. Carolin, et al.
(author)
-
Genome deterioration : Loss of repeated sequences and accumulation of junk DNA
- 2002
-
In: Genetica. - 0016-6707 .- 1573-6857. ; 115:1, s. 1-12
-
Journal article (peer-reviewed)abstract
- A global survey of microbial genomes reveals a correlation between genome size, repeat content and lifestyle. Free-living bacteria have large genomes with a high content of repeated sequences and self-propagating DNA, such as transposons and bacteriophages. In contrast, obligate intracellular bacteria have small genomes with a low content of repeated sequences and no or few genetic parasites. In extreme cases, such as in the 650 kb-genomes of aphid endosymbionts of the genus Buchnera all repeated sequences above 200bp have been eliminated. We speculate that the initial downsizing of the genomes of obligate symbionts and parasites occurred by homologous recombination at repeated genes, leading to the loss of large blocks of DNA as well as to the consumption of repeated sequences. Further sequence elimination in these small genomes seems primarily to result from the accumulation of short deletions within genic sequences. This process may lead to temporary increases in the genomic content of pseudogenes and 'junk' DNA. We discuss causes and long-term consequences of extreme genome size reductions in obligate intracellular bacteria.
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| 17. |
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| 18. |
- Frank, Anna Carolin, 1974-
(author)
-
Lifestyle and Genome Evolution in Vector-Borne Bacteria : A Comparison of Three Bartonella Species
- 2005
-
Doctoral thesis (other academic/artistic)abstract
- Bacterial genomes provide records of the molecular processes associated with emergence and evolution of different bacterial lifestyles. This thesis is based on whole-genome comparisons within the genus Bartonella, an excellent model system for studies of host- and vector-specificity and infection outcome in animal-associated bacteria. The louse-borne human specialist and trench fever agent Bartonella quintana was contrasted to the flea-borne generalist relatives Bartonella henselae and Bartonella grahamii, which cause asymptomatic infection in cat and mouse respectively. While B. henselae is commonly isolated from humans, and causes cat scratch disease, there is only one reported case of B. grahamii human infection. The gene complements of the three species are nested like Russian dolls with the smaller genome (B. quintana) being entirely contained in the medium sized (B. henselae), which in turned is contained in the largest (B. grahamii). Size differences reflect differences in the horizontally and vertically acquired gene content, and in the number of genus- and species- specific genes, owing to differential impact of bacteriophages and plasmids, and to different degrees of genome decay. These processes can be attributed to the three distinct lifestyles. Comparisons with other alpha-proteobacteria suggest that the Bartonella genus as a whole evolved from plant-associated species, and that horizontal transfer, in particular of genes involved in interaction with the host, played a key role in the transition to animal intracellular lifestyle. The long-term genome decay associated with this lifestyle is most advanced in the host-restricted B. quintana. The broad host-range species B. grahamii has the largest genome and the largest proportion of auxiliary DNA of the three, probably because it has access to a larger gene pool. In encodes all the known pathogenicity determinants found in the genomes of B. henselae and B. quintana, suggesting that these genes primarily evolved to facilitate colonization in the reservoir host.
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| 19. |
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| 20. |
- Frank, Carolin, et al.
(author)
-
Functional divergence and horizontal transfer of type IV secretion systems
- 2005
-
In: Molecular biology and evolution. - : Oxford University Press (OUP). - 0737-4038 .- 1537-1719. ; 22:5, s. 1325-36
-
Journal article (peer-reviewed)abstract
- The type IV secretion system (TFSSs) is a multifunctional family of translocation pathways that mediate the transfer of DNA among bacteria and deliver DNA and proteins to eukaryotic cells during bacterial infections. Horizontal transmission has dominated the evolution of the TFSS, as demonstrated here by a lack of congruence between the tree topology inferred from components of the TFSS and the presumed bacterial species divergence pattern. A parsimony analysis suggests that conjugation represents the ancestral state and that the divergence from conjugation to secretion of effector molecules has occurred independently at multiple sites in the tree. The result shows that the nodes at which functional shifts have occurred coincide with those of horizontal gene transfers among distantly related bacteria. We suggest that it is the transfer between species that paved the way for the divergence of the TFSSs and discuss the general role of horizontal gene transfers for the evolution of novel gene functions.
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| 21. |
- Gilles, Stefanie, et al.
(author)
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Pollen exposure weakens innate defense against respiratory viruses.
- 2020
-
In: Allergy. - : Wiley. - 1398-9995 .- 0105-4538. ; 75:3, s. 576-587
-
Journal article (peer-reviewed)abstract
- Hundreds of plant species release their pollen into the air every year during early spring. During that period, pollen allergic as well as non-allergic patients frequently present to doctors with severe respiratory tract infections.To assess whether pollen may interfere with antiviral immunity.We combined data from real life human exposure cohorts, a mouse model and human cell culture to test our hypothesis.Pollen significantly diminished interferon-λ and pro-inflammatory chemokine responses of airway epithelia to rhinovirus and viral mimics and decreased nuclear translocation of interferon regulatory factors. In mice infected with respiratory syncytial virus, co-exposure to pollen caused attenuated antiviral gene expression and increased pulmonary viral titers. In non-allergic human volunteers, nasal symptoms were positively correlated with airborne birch pollen abundance, and nasal birch pollen challenge led to down-regulation of type I and -III interferons in nasal mucosa. In a large patient cohort, numbers of rhinovirus-positive cases were correlated with airborne birch pollen concentrations.The ability of pollen to suppress innate antiviral immunity, independent of allergy, suggests that high-risk population groups should avoid extensive outdoor activities when pollen and respiratory virus seasons coincide.
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| 22. |
- Goodwin, Guy M., et al.
(author)
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From neuroscience to evidence based psychological treatments - The promise and the challenge, ECNP March 2016, Nice, France
- 2018
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In: European Neuropsychopharmacology. - : Elsevier BV. - 0924-977X .- 1873-7862. ; 28:2, s. 317-333
-
Journal article (peer-reviewed)abstract
- This ECNP meeting was designed to build bridges between different constituencies of mental illness treatment researchers from a range of backgrounds with a specific focus on enhancing the development of novel, evidence based, psychological treatments. In particular we wished to explore the potential for basic neuroscience to support the development of more effective psychological treatments, just as this approach is starting to illuminate the actions of drugs. To fulfil this aim, a selection of clinical psychologists, psychiatrists and neuroscientists were invited to sit at the same table. The starting point of the meeting was the proposition that we know certain psychological treatments work, but we have only an approximate understanding of why they work. The first task in developing a coherent mental health science would therefore be to uncover the mechanisms (at all levels of analysis) of effective psychological treatments. Delineating these mechanisms, a task that will require input from both the clinic and the laboratory, will provide a key foundation for the rational optimisation of psychological treatments. As reviewed in this paper, the speakers at the meeting reviewed recent advances in the understanding of clinical and cognitive psychology, neuroscience, experimental psychopathology, and treatment delivery technology focussed primarily on anxiety disorders and depression. We started by asking three rhetorical questions: What has psychology done for treatment? What has technology done for psychology? What has neuroscience done for psychology? We then addressed how research in five broad research areas could inform the future development of better treatments: Attention, Conditioning, Compulsions and addiction, Emotional Memory, and Reward and emotional bias. Research in all these areas (and more) can be harnessed to neuroscience since psychological therapies are a learning process with a biological basis in the brain. Because current treatment approaches are not fully satisfactory, there is an imperative to understand why not. And when psychological therapies do work we need to understand why this is the case, and how we can improve them. We may be able to improve accessibility to treatment without understanding mechanisms. But for treatment innovation and improvement, mechanistic insights may actually help. Applying neuroscience in this way will become an additional mission for ECNP. (C) 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
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| 23. |
- Grasset, Charlotte, et al.
(author)
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The CO2-equivalent balance of freshwater ecosystems is non-linearly related to productivity
- 2020
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In: Global Change Biology. - : John Wiley & Sons, Ltd. - 1354-1013 .- 1365-2486. ; 26:10, s. 5705-5715
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Journal article (peer-reviewed)abstract
- Eutrophication of fresh waters results in increased CO2 uptake by primary production, but at the same time increased emissions of CH4 to the atmosphere. Given the contrasting effects of CO2 uptake and CH4 release, the net effect of eutrophication on the CO2-equivalent balance of fresh waters is not clear. We measured carbon fluxes (CO2 and CH4 diffusion, CH4 ebullition) and CH4 oxidation in 20 freshwater mesocosms with 10 different nutrient concentrations (total phosphorus range: mesotrophic 39 µg/L until hypereutrophic 939 µg/L) and planktivorous fish in half of them. We found that the CO2-equivalent balance had a U-shaped relationship with productivity, up to a threshold in hypereutrophic systems. CO2-equivalent sinks were confined to a narrow range of net ecosystem production (NEP) between 5 and 19 mmol O2 m?3 day?1. Our findings indicate that eutrophication can shift fresh waters from sources to sinks of CO2-equivalents due to enhanced CO2 uptake, but continued eutrophication enhances CH4 emission and transforms freshwater ecosystems to net sources of CO2-equivalents to the atmosphere. Nutrient enrichment but also planktivorous fish presence increased productivity, thereby regulating the resulting CO2-equivalent balance. Increasing planktivorous fish abundance, often concomitant with eutrophication, will consequently likely affect the CO2-equivalent balance of fresh waters.
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| 24. |
- Menzel, Carolin, et al.
(author)
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Alkylresorcinols in Swedish cereal food products
- 2012
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In: Journal of Food Composition and Analysis. - : Elsevier BV. - 0889-1575 .- 1096-0481. ; 28:2, s. 119-125
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Journal article (peer-reviewed)abstract
- In this study alkylresorcinol (AR) content and homologue composition was determined in 159 cereal products commonly consumed in Sweden. Food items were sorted into seven groups including soft bread, crisp bread, breakfast cereals, pasta, flour, cookies and other cereal products with varying content of rye, wheat, oat, corn, rice and maize. The analyzed total AR content ranged from not detectable to 4178 μg/g (fresh weight). Bran and whole grain (WG) items showed highest AR contents and were comparable to previous reports. The AR content was strongly correlated with WG content from rye and wheat cereals (r = 0.80, P < 0.001), the main source of AR. In addition, the calculated ratio of the homologues C17:0 and C21:0, which was previously reported to distinguish between rye and wheat products, was associated to the proportion of rye content in WG of wheat and rye (r = 0.83, P < 0.001). The data from the present study can be used to estimate AR intake from WG of rye and wheat in the Swedish population and the results indicated that WG content from rye and wheat may be predicted by using AR content and homologue composition in cereal products.
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| 25. |
- Menzel, Carolin, et al.
(author)
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Molecular structure of citric acid cross-linked starch films
- 2013
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In: Carbohydrate Polymers. - Amsterdam : Elsevier. - 0144-8617 .- 1879-1344. ; 96:2, s. 270-276
-
Journal article (peer-reviewed)abstract
- The effect of citric acid (CA) on starch films has been examined. A new method to detect cross-linkingof starch by CA in solution-cast films by molecular weight measurements is described. Furthermore, wemanaged to distinguished between free, mono- and di-esterified CA and quantify di-ester content withinstarch films by using a modification in the method of complexometric titration with copper(II)-sulfate.Cross-linking of starch by CA occurred at low temperature, 70◦C, which we assumed is so far the lowesttemperature reported where cross-linking reaction occurred. This is essential for starch coating applica-tions within paper industry since no high temperatures for curing will be required. However, curing at150◦C and high CA concentrations, 30 pph, increased cross-linking reaction. Furthermore, the physicalproperties like water solubility, gel content and glass transition temperature, were highly reflected bychanges in the molecular structure i.e. cross-linking and hydrolysis, as well as CA content and curingtemperature.
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| 26. |
- Muneer, Faraz, et al.
(author)
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Innovative Gliadin/Glutenin and Modified Potato Starch Green Composites : Chemistry, Structure, and Functionality Induced by Processing
- 2016
-
In: ACS Sustainable Chemistry and Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 4:12, s. 6332-6343
-
Journal article (peer-reviewed)abstract
- In this study, we combined two wheat proteins, gliadin (Gli)/glutenin (GT), and modified potato starch (MPS) into composites using extrusion. In the Gli/GT MPS composites, we studied the structural dynamics of proteins and starch, protein starch interactions, protein properties, and composite morphology in relation to mechanical and barrier properties. Materials with different ratios of Gli/GT and MPS were extruded using either glycerol or glycerol water at 110 and 130 degrees C. For the first time, a hierarchical hexagonal structure of Gli proteins was observed in Gli MPS composite at both extrusion temperatures. The higher temperature (130 degrees C) induced a higher degree of protein cross-links, an increase in the polymer size, and formation of beta-sheets compared to 110 degrees C. The combination of plasticizers (glycerol and water) favored a micro-structural morphology with improved gelatinization of starch, processability, as well as strength, stiffness, and extensibility of GT MPS composites. The highest amount of the oxidized proteins was observed in the samples with the highest protein content and at high extrusion temperature. The Gli- and GT MPS (30/70) samples showed promising oxygen barrier properties under ambient testing conditions. These findings provide in-depth information for tailoring the structural functional relationship of the Gli/GT-potato starch composites for their promising use in designing various green materials.
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| 27. |
- Muneer, Faraz, et al.
(author)
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Nanostructural Morphology of Plasticized Wheat Gluten and Modified Potato Starch Composites: Relationship to Mechanical and Barrier Properties
- 2015
-
In: Biomacromolecules. - : American Chemical Society (ACS). - 1526-4602 .- 1525-7797. ; 16:3, s. 695-705
-
Journal article (peer-reviewed)abstract
- In the present study, we were able to produce composites of wheat gluten (WG) protein and a novel genetically modified potato starch (MPS) with attractive mechanical and gas barrier properties using extrusion. Characterization of the MPS revealed an altered chain length distribution of the amylopectin fraction and slightly increased amylose content compared to wild type potato starch. WG and MPS of different ratios plasticized with either glycerol or glycerol and water were extruded at 110 and 130 °C. The nanomorphology of the composites showed the MPS having semicrystalline structure of a characteristic lamellar arrangement with an approximately 100 Å period observed by small-angle X-ray scattering and a B-type crystal structure observed by wide-angle X-ray scattering analysis. WG has a structure resembling the hexagonal macromolecular arrangement as reported previously in WG films. A larger amount of β-sheets was observed in the samples 70/30 and 30/70 WG-MPS processed at 130 °C with 45% glycerol. Highly polymerized WG protein was found in the samples processed at 130 °C versus 110 °C. Also, greater amounts of WG protein in the blend resulted in greater extensibility (110 °C) and a decrease in both E-modulus and maximum stress at 110 and 130 °C, respectively. Under ambient conditions the WG-MPS composite (70/30) with 45% glycerol showed excellent gas barrier properties to be further explored in multilayer film packaging applications.
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| 28. |
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| 29. |
- Nystedt, Björn, et al.
(author)
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Diversifying Selection and Concerted Evolution of a Type IV Secretion System in Bartonella
- 2008
-
In: Molecular biology and evolution. - : Oxford University Press (OUP). - 0737-4038 .- 1537-1719. ; 25:2, s. 287-300
-
Journal article (peer-reviewed)abstract
- We have studied the evolution of a type TV secretion system (T4SS), in Bartonella, which is thought to have changed function from conjugation to erythrocyte adherence following a recent horizontal gene transfer event. The system, called Trw, is unique among T4SSs in that genes encoding both exo- and intracellular components are located within the same duplicated fragment. This provides an opportunity to study the influence of selection on proteins involved in host-pathogen interactions. We sequenced the trw locus from several strains of Bartonella henselae and investigated its evolutionary history by comparisons to other Bartonella species. Several instances of recombination and gene conversion events where detected in the 2- to 5-fold duplicated gene fragments encompassing trwJIH, explaining the homogenization of the anchoring protein TrwI and the divergence of the minor pilus protein TrwJ. A phylogenetic analysis of the 7- to 8-fold duplicated gene coding for the major pilus protein TrwL displayed 2 distinct clades, likely representing a subfunctionalization event. The analyses of the B. henselae strains also identified a recent horizontal transfer event of almost the complete trwL region. We suggest that the switch in function of the T4SS was mediated by the duplication of the genes encoding pilus components and their diversification by combinatorial sequence shuffling within and among genomes. We suggest that the pilus proteins have evolved by diversifying selection to match a divergent set of erythrocyte surface structures, consistent with the trench warfare coevolutionary model.
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| 32. |
- Olsson, Erik, 1984-, et al.
(author)
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The effect of pH on hydrolysis, cross-linking and barrier properties of starch barriers containing citric acid
- 2013
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In: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 98:2, s. 1505-1513
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Journal article (peer-reviewed)abstract
- Green cross-linking of thermoplastic starch for food packaging applications has been intensely studied during the last decade as a method of producing water-insensitive renewable barriers. This work has shown how the barrier properties of paper coated with a barrier dispersion containing starch and citric acid were affected by the solution pH and the drying temperature. The barrier properties of the coated paper were linked to molecular properties showing both hydrolysis and cross-linking reaction of starch in the presence of citric acid at different solution pH and different reaction temperatures (curing) on cast films. Hydrolysis was shown to be almost completely hindered at solution pH ≥4 at curing temperatures ≤ 105 °C and at pH ≥ 5 at curing temperatures ≤150 °C, whereas cross-linking still occurred to some extent at pH ≤ 6.5 and drying temperatures as low as 70 °C. The water vapor transmission rate was significantly affected by the competition between these two reactions. Coated paper showed a minimum in water vapor transmission rate at pH was kept around 4 in the starch coating solution, corresponding to the point where hydrolysis was effectively hindered but where a significant degree of cross-linking still occurred.
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| 33. |
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| 34. |
- Rattenborg, Rune, 1983-, et al.
(author)
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Cuneiform Inscriptions Geographical Site Index (CIGS)
- 2021
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Other publicationabstract
- This index contains a basic set of primary spatial, toponym, attribute, and external link information on more than 500 archaeological locations where texts written in cuneiform and derived scripts have been found, prepared by researchers of the Department of Linguistics and Philology of Uppsala University. The index is intended as a tool for students and researchers in cuneiform studies and related areas and as an aid to cultural heritage managers and educators in communicating and safeguarding this unique body of world written heritage.The version 1.2 index contains a total nineteen fields, namely one primary ID, one spatial accuracy field, six integer and string fields for external data links, nine string fields with toponyms, and two integer fields making up the point coordinate of the record. Coordinates given use the WGS 1984 geographic coordinate reference system (EPSG 4326) and have been truncated to four decimal digits. Site locations have been traced from archaeological gazetteers and web mapping services (e.g. Pleiades and OpenStreetMap) and digitally generated from optical recognition using current and legacy satellite imagery datasets in QGIS 3.x.
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| 35. |
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| 36. |
- Rattenborg, Rune, PhD (Dunelm), 1983-, et al.
(author)
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The Cuneiform Corpus: A Provisional Survey
- 2022
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Conference paper (other academic/artistic)abstract
- While generally recognised as one of the oldest and longest-lived scripts in human history, the sheer size of the cuneiform corpus, certainly one of the largest discrete bodies of written sources from the ancient world, is seldom properly appreciated. The present paper offers first a review and an evaluation of past quantitative assessments of the cuneiform corpus and current levels of catalogue digitisation and integration. This serves to define lacunae in general indices currently available and principal issues relating to the quantification and interrogation of textual sources at the level of an entire corpus. We then proceed to discuss the distribution of the cuneiform corpus as an archaeological artefact, combining a newly developed open access spatial index of archaeological locations from across Europe, Asia, and Africa where cuneiform texts have been found (Rattenborg et al. 2021) with a quantitative survey based on aggregate numbers from scholarly literature. Aided by an extremely broad diachronic and diatopic outlook on a uniquely large body of written source material, this study sheds a first light on the full extent and prevalence of cuneiform inscriptions in the archaeological record.Geomapping Landscapes of Writing (GLoW). Department of Linguistics and Philology - Uppsala University. https://www.lingfil.uu.se/research/assyriology/glow/. Rattenborg, Rune, Carolin Johansson, Seraina Nett, Gustav Ryberg Smidt, and Jakob Andersson (2021) ‘An Open Access Index for the Geographical Distribution of the Cuneiform Corpus’. Cuneiform Digital Library Journal 2021/1: 1–12. http://www.cdli.ucla.edu/pubs/cdlj/2021/cdlj2021_001.html
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| 37. |
- Rattenborg, Rune, PhD (Dunelm), 1983-, et al.
(author)
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Would You Consider Your Repository to Be Complete? : Metadata Standards and the Digital Landscape(s) of Cuneiform Studies
- 2021
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Conference paper (other academic/artistic)abstract
- Standardizing, integrating, and linking metadata collections for digital text catalogues will be among the most pressing tasks facing students of cuneiform texts in coming decades. Digital research environments now extend into virtually every aspect of scholarly workflows, encompassing not only the rendition of inscriptions in a digital form, but also a wide range of metadata entities spanning artefactual, linguistic, spatial, temporal, and bibliographical aspects of cuneiform texts in their historical, archaeological, and museal setting. Not only the inscriptions, but also considerable parts of our knowledge about them, are rapidly being transformed into digital and extraordinarily dynamic resources. Furthering the integration and interoperability of such resources will be a key prerequisite for unleashing the full potential of the cuneiform corpus – certainly one of the largest bodies of historical documentation ever known – for future research and learning. Within this sprawling digital landscape, efforts at interconnecting data collections are faced with a vast undergrowth of discrete projects, registers, and collections with only limited reference to centralized, controlled indices and vocabularies for the definition of basic metadata entities. Introducing Geomapping Landscapes of Writing (GLoW), a three-year research project with the Uppsala University Department of Linguistics and Philology and funded by the Riksbankens Jubileumsfond, this paper reviews a program of surveying, querying, and curating metadata collections for cuneiform studies. In so doing, we point to principal lacunae in the overall coverage of current digital catalogues, potential for linking repositories, and suggestions for best practice in the generation and preservation of metadata collections in the field.
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| 42. |
- Wang-Hansen, Carolin, 1982, et al.
(author)
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Characterization of particulate matter from direct injected gasoline engines
- 2013
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In: Topics in Catalysis. - : Springer Science and Business Media LLC. - 1572-9028 .- 1022-5528. ; 56:1-8, s. 446-451
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Journal article (peer-reviewed)abstract
- The reactivity and reaction kinetics of particulate matter (PM) from direct injected gasoline (GDI) engines has been studied by O2 and NO2 based temperature programmed and isothermal step-response experiments, and the PM nano-structure has been characterized using HRTEM. The reactivity of the PM samples collected in filters during on-road driving was found to increase in the following order: Printex U\diesel\gasoline PI & gasoline DI\ethanol for O2 based combustion. The activation energies for O2 and NO2 based oxidation of PM collected from a GDI engine in an engine bench set-up was estimated to 146 and 71 kJ/mol respectively, which is comparable to corresponding values reported for diesel and model soot. Similar nano-structure features (crystallites plane dimensions, curvature and relative orientation) as observed for diesel soot were observed for gasoline PM.
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| 43. |
- Wang-Hansen, Carolin, 1982, et al.
(author)
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Experimental Method for Kinetic Studies of Gas-Solid Reactions: Oxidation of Carbonaceous Matter
- 2011
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In: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 115:32, s. 16098-16108
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Journal article (peer-reviewed)abstract
- A methodology comprising careful consideration of sample preparation, reactor design, experimental procedures, and data evaluation routines for precise analysis of the kinetics of gas␣solid reactions, specifically the oxidation of carbonaceous materials, has been developed and validated. The wellcontrolled solvent-free deposition of the carbonaceous material onto cordierite monolith substrates ensures experimental stud- ies in the absence of diffusion limitations, temperature gradients, and hot zones. These critical aspects are supported also by theoretical considerations. Temperature-programmed oxida- tion and isothermal oxygen step-response experiments in a continuous gas-flow reactor using a homogeneous synthetic carbon- black material demonstrate excellent reproducibility, and the conversion profiles agree well with previously reported data. An independent set of global kinetic parameters was estimated for each 5% subconversion interval using linear regression such that the conversion dependence of each parameter could be analyzed separately and compared to previously published data. The results show that the evolution of reactive carbons cannot be described with a single global reaction order. This is supported by intermittent ex situ measurements of the specific surface area of the carbon-black material during the course of isothermal oxidation, which reveals a developing microporous structure at high conversions. Physically the changes in carbon reaction order are interpreted as changes in fraction of accessible reactive carbon atoms during progressing oxidation. Moreover, at high conversions, the carbon reaction order approaches 0.7 implying not only that the evolution of the concentration of reactive carbon atoms is proportional to the external surface area of shrinking spheres but also that these spheres have approximately the same size.
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| 44. |
- Wang-Hansen, Carolin, 1982, et al.
(author)
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Kinetic analysis of O2- and NO2-based oxidation of synthetic soot
- 2013
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In: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 117:1, s. 522-531
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Journal article (peer-reviewed)abstract
- This study demonstrates the application of two different methods to evaluate the kinetics of O-2- and NO2-based oxidation of carbonaceous matter. The influence of reactor setup and experiment execution on the accuracy and interpretation of the kinetic parameters is also discussed. The fundamental difference between the two methods lies in how rate changes during the progress of oxidation are interpreted: by changes in the fraction of atoms available for reaction (traditional approach) or by changes in the activation energy (unconventional approach). Using the traditional approach, it was found that two parallel reactions with a first-order reaction model and a third-order Avrami-Erofeyev model could accurately reproduce the O-2-based oxidation curves. The same model (with a different set of parameter values) could also describe the NO2-based kinetics. The unconventional method also provided an accurate representation of the data and can thus function as a complementary evaluation method.
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| 45. |
- Zhou, Yongqiang, et al.
(author)
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Selective Exclusion of Aromatic Organic Carbon During Lake Ice Formation
- 2023
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In: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 50:4
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Journal article (peer-reviewed)abstract
- Earth's lakes at northern latitudes are mostly ice-covered in winter. When lake water freezes, some organic matter dissolved in the water is excluded from the ice. We performed complementary field sampling and laboratory freeze-up experiments to explore how freeze-up may impact the partitioning and composition of dissolved organic matter (DOM) in boreal lakes. We found that 16.2 ± 4.7% of dissolved organic carbon (DOC) was retained in the overlying ice, 81.3 ± 5.7% of DOC was expelled to underlying unfrozen water, and 1.3 ± 0.7% was expelled as flocs. During ice formation, nitrogen (TDN, total dissolved nitrogen), ions (specific conductance), and oxidized and aromatic DOM were preferentially expelled to the underlying water column. The apparent retention factor DOCIce: DOCBefore decreased from clearwater to brownwater lakes, that is, with increasing allochthonous DOC lost from lake ice, indicating that DOM exclusion from the ice cover will become more prevalent as lakes experience browning.
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