| 1. |
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| 2. |
- Porcu, E, et al.
(författare)
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Mendelian randomization integrating GWAS and eQTL data reveals genetic determinants of complex and clinical traits
- 2019
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Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1, s. 3300-
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Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) have identified thousands of variants associated with complex traits, but their biological interpretation often remains unclear. Most of these variants overlap with expression QTLs, indicating their potential involvement in regulation of gene expression. Here, we propose a transcriptome-wide summary statistics-based Mendelian Randomization approach (TWMR) that uses multiple SNPs as instruments and multiple gene expression traits as exposures, simultaneously. Applied to 43 human phenotypes, it uncovers 3,913 putatively causal gene–trait associations, 36% of which have no genome-wide significant SNP nearby in previous GWAS. Using independent association summary statistics, we find that the majority of these loci were missed by GWAS due to power issues. Noteworthy among these links is educational attainment-associated BSCL2, known to carry mutations leading to a Mendelian form of encephalopathy. We also find pleiotropic causal effects suggestive of mechanistic connections. TWMR better accounts for pleiotropy and has the potential to identify biological mechanisms underlying complex traits.
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| 3. |
- Carter, J. A., et al.
(författare)
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Ground-based and additional science support for SMILE
- 2024
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Ingår i: Earth and Planetary Physics. - : Science Press. - 2096-3955. ; 8:1, s. 275-298
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Tidskriftsartikel (refereegranskat)abstract
- The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer (SMILE) mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions, and simultaneously monitor the auroral response of the Northern Hemisphere ionosphere. Combining these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE mission. Here, we describe current community efforts to prepare for SMILE, and the benefits and context various experiments that have explicitly expressed support for SMILE can offer. A dedicated group of international scientists representing many different experiment types and geographical locations, the Ground-based and Additional Science Working Group, is facilitating these efforts. Preparations include constructing an online SMILE Data Fusion Facility, the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar, and the consideration of particular observing strategies and spacecraft conjunctions. We anticipate growing interest and community engagement with the SMILE mission, and we welcome novel ideas and insights from the solar-terrestrial community.
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| 4. |
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| 5. |
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| 6. |
- Andersson, M., et al.
(författare)
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A New Class of Labile Surfactants that Break Down to Non-surface Active Products upon Heating or after a Pre-set Time, without the Need for a pH Change
- 2007
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Ingår i: Tenside Surfactants Detergents. - : Walter de Gruyter GmbH. - 0932-3414 .- 2195-8564. ; 44:6, s. 366-372
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Tidskriftsartikel (refereegranskat)abstract
- A new class of labile surfactants that break down at a controllable rate without the need for a change in pH will be presented. The invention has been patented by YKI Institute for Surface Chemistry, and is based on use of β-keto acids or their salts as surface-active compounds. These surfactants spontaneously break down through decarboxylation, to form an oil-like ketone and CO 2/HCO 3 -/CO 32 - depending on pH. The rate of breakdown can be controlled within a wide range by temperature or by certain additives, but, unlike most cleavable surfactants, a change in pH is not needed. Furthermore the surfactants can be conveniently activated from a stabile precursor just before use, and one (of many possible) precursors of this kind is already available on the industrial scale in the form of a wellknown chemical that is FDA-approved in other, non-surfactant, applications. The compound in question, alkyl ketene dimer (AKD), is produced in large scale by a number of large chemical producers today, and used for hydrophobization of paper. The present article gives an overview of the surfactant chemistry, with focus on recent studies of the kinetics of activation of the surfactant precursor and breakdown kinetics of the labile surfactant at different conditions. Furthermore, possible industrial applications of the surfactant will be discussed, with one example taken from a recent feasibility study performed within the car washing area. © Carl Hanser Publisher.
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| 7. |
- Branduardi-Raymont, G., et al.
(författare)
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Exploring solar-terrestrial interactions via multiple imaging observers
- 2022
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Ingår i: Experimental astronomy. - : Springer Nature. - 0922-6435 .- 1572-9508. ; 54:2-3, s. 361-390
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Tidskriftsartikel (refereegranskat)abstract
- How does solar wind energy flow through the Earth's magnetosphere, how is it converted and distributed? is the question we want to address. We need to understand how geomagnetic storms and substorms start and grow, not just as a matter of scientific curiosity, but to address a clear and pressing practical problem: space weather, which can influence the performance and reliability of our technological systems, in space and on the ground, and can endanger human life and health. Much knowledge has already been acquired over the past decades, particularly by making use of multiple spacecraft measuring conditions in situ, but the infant stage of space weather forecasting demonstrates that we still have a vast amount of learning to do. A novel global approach is now being taken by a number of space imaging missions which are under development and the first tantalising results of their exploration will be available in the next decade. In this White Paper, submitted to ESA in response to the Voyage 2050 Call, we propose the next step in the quest for a complete understanding of how the Sun controls the Earth's plasma environment: a tomographic imaging approach comprising two spacecraft in highly inclined polar orbits, enabling global imaging of magnetopause and cusps in soft X-rays, of auroral regions in FUV, of plasmasphere and ring current in EUV and ENA (Energetic Neutral Atoms), alongside in situ measurements. Such a mission, encompassing the variety of physical processes determining the conditions of geospace, will be crucial on the way to achieving scientific closure on the question of solar-terrestrial interactions.
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| 8. |
- Hull, A, et al.
(författare)
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Vapour-liquid equilibrium of binary mixtures. 1. Ethanol-1-butanol, ethanol + octane, 1-butanol + octane
- 2006
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Ingår i: Journal of Chemical and Engineering Data. - 0021-9568 .- 1520-5134. ; 51, s. 1996-2001
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Tidskriftsartikel (refereegranskat)abstract
- The activity coefficients of the binary mixtures ethanol + 1-butanol, ethanol + octane, and 1-butanol + octane were determined at temperatures of (308.15, 313.15, and 318.15) K. The determination of the vapor phase composition at equilibrium was carried out using headspace gas chromatography analysis. Multiple headspace extraction was used to calibrate the headspace gas chromatograph. Comparison of the phase diagrams produced using standard Legendre orthogonal polynomial techniques with phase diagrams from the literature showed good agreement. The composition of the azeotropes were reported, where applicable.
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| 9. |
- Hull, A, et al.
(författare)
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Vapour-liquid equilibrium of binary mixtures. 2. Ethanol + 2,2,4-trimethylpentane, 1-butanol + 2,2,4-trimethylpentane, and ethanol + o-xylene
- 2006
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Ingår i: Journal of Chemical and Engineering Data. - 0021-9568 .- 1520-5134. ; 51, s. 2002-2008
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Tidskriftsartikel (refereegranskat)abstract
- The activity coefficients of the binary mixtures ethanol + 2,2,4-trimethylpentane, 1-butanol + 2,2,4-trimethylpentane, and ethanol + o-xylene were determined at temperatures of (308.15, 313.15, and 318.15) K. The determination of the vapor phase composition at equilibrium was carried out using headspace gas chromatography analysis. Multiple headspace extraction was used to calibrate the headspace gas chromatograph. Comparison of the experimental phase diagrams with phase diagrams from the literature shows good agreement. The composition of the azeotropes are reported, where they exist. The molar Gibbs energy of mixing is reported for all mixtures studied. The infinite dilution activity coefficients are reported for all components of all mixtures. Some thermodynamic models (those of Wilson, NRTL, UNIQUAC, and Flory-Scatchard) have been compared with regard to their suitability for modeling the experimental data.
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| 10. |
- Kronberg, B, et al.
(författare)
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Preparation and evaluation of sterically stabilized liposomes: colloidal stability, serum stability, macrophage uptake and toxicology
- 1990
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Ingår i: Journal of Pharmaceutical Sciences. - 0022-3549 .- 1520-6017. ; 79, s. 667-671
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Tidskriftsartikel (refereegranskat)abstract
- Sterically stabilized liposomes were produced by incorporating a nonionic surfactant, polysorbate 80 (Tween 80), into the lipid bilayer. The sterically stabilized liposomes exhibited a superior entrapment stability compared with surfactant-free liposomes (i.e., liposomes prepared with lipids and cholesterol). The sterically stabilized liposomes were stable at high calcium ion concentrations, and liposome-entrapped carboxyflourescein was retained within the stabilized liposomes in the presence of serum for at least 5 h. The macrophage uptake of the sterically stabilized liposomes was comparable to that of liposomes containing lipids and cholesterol. The sterically stabilized liposomes were non-toxic, in concentrations up to 3.0 mM, to macrophages. These results indicate that polysorbate 80 can be used to produce stable liposomes without changing the uniqe macrophage distribution of this drug delivery system.
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| 11. |
- Nakamura, R., et al.
(författare)
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Flow bouncing and electron injection observed by Cluster
- 2013
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Ingår i: Journal of Geophysical Research-Space Physics. - : American Geophysical Union (AGU). - 2169-9380. ; 118:5, s. 2055-2072
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Tidskriftsartikel (refereegranskat)abstract
- Characteristics of particles and fields in the flow-bouncing region are studied based on multipoint observations from Cluster located at 13-15R(E) downtail during a substorm event around 12:50 UT on 7 September 2007. The Cluster spacecraft were separated by a distance of up to 10,000 km and allowed to determine the mesoscale evolution of the current sheet as well as the development of the dipolarization front. We show that the flow bouncing took place associated with a tailward-directed j x B force in a disturbed current sheet in addition to an enhanced tailward pressure gradient force. Multiple Earthward propagating dipolarization fronts accompanied by enhanced flux of energetic electrons were observed before the flow bouncing. The sequence of events started with a localized dipolarization front and ended with a large scale (>10R(E)) dipolarization front accompanied by a major increase in energetic electrons at all spacecraft and immediately followed by flow bouncing. Multiple dipolarization fronts result in the formation of compressed magnetic field with a plasma bulge bounded by thin ion-scale current layers, a favorable condition for flow bouncing. These observations suggest that to understand the flow bouncing and related acceleration of plasma in the near-Earth tail, both the large-scale MHD properties and the transient and small-scale effect of the plasma interaction with the Earth-dipole field need to be taken into account.
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| 12. |
- Sundberg, DC, et al.
(författare)
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Morphology development of polymeric microparticles in aqueous dispersions. I. Thermodynamic considerations
- 1990
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Ingår i: Journal of Applied Polymer Science. - 0021-8995 .- 1097-4628. ; 41, s. 1425-1442
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Tidskriftsartikel (refereegranskat)abstract
- A thermodynamic analysis of polymer particle morphology highlights the role of interfacial tensions in controlling particle structure. The influence of the surfactant and the nature of the incompatible polymers is seen through their individual and collective effects upon these interfacial tensions. It has been found that by simply changing the type of surfactant used in the emulsion the particle morphology can change from core-shell to hemispherical, in agreement with thermodynamic predictions. Several apparently different morphologies (hemispherical, sandwich, multiple lobes) have been found to coexist at the same time within a single emulsion, suggesting that they may be simply different states of phase separation and not thermodynamically stable, unique morphologies. The thermodynamic analyses are independent of particle size and method of emulsion processing. Experimental evidence shows that the morphology of particles formed via in situ polymerization ( as in a synthetic latex) is controlled by interfacial tensions in the same manner as those particles formed via solvent evaporation from a solution of an incompatible polymer pair ( as in an artificial latex or microencapsulation).
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| 13. |
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| 14. |
- Boschkova, K, et al.
(författare)
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Frictional properties of lyotropic liquid crystalline mesophases at surfaces
- 2000
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Ingår i: Colloids and Surfaces A. - 0927-7757 .- 1873-4359. ; 166, s. 67-77
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Tidskriftsartikel (refereegranskat)abstract
- The lubricating effect of assemblies of amphiphiles at surfaces has been studied. Liquid crystalline mesophases were investigated in terms of frictional and wear properties in a pin on disc rig. It is shown that systems forming lamellar liquid crystals indeed serve as lubricating liquids, indicating that the lamellar liquid crystalline phase adsorb on the steel surface forming a lubricating tribofilm. Poor performance is obtained when the lubricating system is in a single phase, i.e. in this case a lamellar liquid crystalline region. However, good lubrication is found when the lamellar liquid crystalline phase is dispersed in the water. This is attributed to a low viscosity of the system rendering a fast relaxation of the system in order to form a new film after the disturbing action of the two sliding surfaces. The lamellar packing is altered by the addition of non-charged amphiphiles, such as short chain alcohols. Using different alcohols it was shown that aromatic short chain alcohols are detrimental to the wear. This was attributed to the Rebinder effect, i.e. a strong adsorption of the alcohol, which in turn facilitates crack formation and thus the wear. In systems with mixtures of cat- and anionic amphiphiles it was, not surprisingly found that the best lubrication is obtained with a slight excess of either surfactant.
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| 15. |
- Gerhardsson, H., et al.
(författare)
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Transitioning the Swedish building sector toward reuse and circularity
- 2020
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Ingår i: IOP Conference Series. - : Institute of Physics (IOP). - 1755-1307 .- 1755-1315. ; 588:4
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Tidskriftsartikel (refereegranskat)abstract
- A transition toward a circular building sector, in which built-in construction products with remaining technical life are reused, would decrease the amount of waste generated, improve resource utilization and reduce greenhouse gas emissions related to the built environment. Based on this premise, this study (1) identifies key barriers to the increased reuse of high-quality construction products in the Swedish building sector and, based on these barriers (2) presents a set of new working practices that enable reuse in building and deconstruction projects. The study uses an explorative research approach based on data from ten case studies of Swedish building and deconstruction projects, semi-structured interviews and a survey conducted with key building-sector stakeholders. The results identify a lack of knowledge and an immature market as key barriers that must be removed in order to enable increased reuse in the Swedish building sector. Key working practices identified as solutions for increased reuse are (1) materials inventories, (2) targets for reuse, (3) circular building design, (4) planning for reuse, (5) incentives for reuse in procurement and (6) long-term documentation strategies enabling future reuse. © Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Published under licence by IOP Publishing Ltd.
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| 16. |
- Hull, Angelica, et al.
(författare)
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Alternative fuel for a standard diesel engine
- 2006
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Ingår i: International Journal of Engine Research. - 1468-0874 .- 2041-3149. ; 7:1, s. 51-63
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Tidskriftsartikel (refereegranskat)abstract
- Alternative fuels have been developed for the commercial diesel products Mkl and EN590. Appropriate additives were selected from a broad range of oxygenates including alcohols, acetals, ethers, esters, and nitrates by a process of systematic elimination. The resulting fuels called Biodiesel 15 meet all existing standards in force for diesel fuel, are stable, and have similar performance characteristics to standard diesel. Significantly Biodiesel 15 is much cleaner than standard diesel with around 30 per cent or more reductions in particulate matter in the exhaust emissions. Carbon dioxide (CO2) emissions are much lower with Biodiesel 15 than with standard diesel products. Other regulated emissions are on a par with Mkl. The fuel consumption of Biodiesel 15 is 2 per cent lower than that of conventional Mkl.
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| 17. |
- Hull, A, et al.
(författare)
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An alternative fuel for spark ignition engines
- 2006
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Ingår i: International Journal of Engine Research. - 1468-0874 .- 2041-3149. ; 7, s. 203-214
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Tidskriftsartikel (refereegranskat)abstract
- Alternative fuels have been developed for standard spark ignition engines. The fuels, which contain generic bio components, maintain all the advantages of ethanol, that is the ability to increase considerably the octane number of gasoline and reduce the amount of harmful pollutants in the exhaust emissions of engines operating on such blends. In contrast to ethanol the new fuel components do not increase the vapour pressure of gasoline-ethanol blends, have a better tolerance to water and do not increase the fuel consumption. The bio component based fuels also compare favourably with mineral sourced octane boosters such as MTBE. Additionally reformulation of the base gasoline becomes unnecessary.
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| 18. |
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| 19. |
- Hull, Angelica, et al.
(författare)
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Vapour-Liquid Equilibrium of Binary Mixtures. Part II; ethanol+2,2,4-trimethyl pentane, 1-butanol+2,2,4-trimethyl pentane, ethanol+o-xylene
- 2006
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Ingår i: J. Chem. Eng. Data, 2006, 51, 2002-2008.
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Tidskriftsartikel (refereegranskat)
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| 20. |
- Kizling, J, et al.
(författare)
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On the formation and stability of concentrated water-in-oil emulsions, aphrons
- 1990
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Ingår i: Colloids and Surfaces. - 0166-6622 .- 1873-4340. ; 50, s. 131-140
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Tidskriftsartikel (refereegranskat)abstract
- The stability of concentrated w/o emulsions is discussed on the basis of stability measurements of systems containinmg water, dodecane ( or hexadecane) and a nonionic surfactant, viz., polyoxyethylene dodecyl ether. In these emulsions the ratio of the dispersed aqueous phase to the organic phase is so high that the aqueous domains are polyhedral, so-called aphrons, so that the maximum available space is filled. The stability is dependent on: (i) the structure of the surfactant, which determines the preferencial solvency of the surfactant in the organic or the aqueous phase; and (ii) the presence of salts in the aqueous phase, which influences the stability by stopping the Ostwald ripening and/or decreasing the attractive force across the oil lamellae between the aqueous droplets.
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| 21. |
- Kizling, J, et al.
(författare)
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On the formation and stability of high internal phase O/W emulsions
- 2006
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Ingår i: Advances in Colloid and Interface Science. - 0001-8686 .- 1873-3727. ; 123-126, s. 295–302-
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Tidskriftsartikel (refereegranskat)abstract
- High internal phase o/w emulsions have been investigated with respect to stability. A series of aliphatic hydrocarbons were used as the oil component. By matching the refractive index of both phases, transparent, concentrated emulsions were produced and these emulsions were found to have the highest long-term stability. The long-term stability of transparent emulsions is attributed to a minimum in free energy at the equilibrium thickness, which, in turn, is related to a reduced attraction over the thin aqueous lamellae. Another factor that contributes to the stability is the absence of the destabilizing mechanisms commonly encountered for ordinary emulsions and foams.
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| 22. |
- Kizling, J, et al.
(författare)
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On the formation of concentrated stable w/o emulsions
- 2001
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Ingår i: Advances in Colloid and Interface Science. - 0001-8686 .- 1873-3727. ; 89-90, s. 395-399
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Tidskriftsartikel (refereegranskat)abstract
- The conditions for the formation of concentrated w/o emulsions based on Aerosol OT and aliphatic hydrocarbons were studied. It was found that high stability is obtained if the attraction between the emulsion droplets is kept to a minimum. This is achieved by matching the refractive index of the dispersed phase and the organic phase. Furthermore, it is shown that the mere presence of salt does not render any stability. Hence, the speculated mechanism that salt stabilises against Ostwald ripening does not hold for these emulsions.
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| 23. |
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| 24. |
- Li, Kun, et al.
(författare)
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Cold Ion Outflow Modulated by the Solar Wind Energy Input and Tilt of the Geomagnetic Dipole
- 2017
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Ingår i: Journal of Geophysical Research - Space Physics. - : American Geophysical Union (AGU). - 2169-9380 .- 2169-9402. ; 122:10, s. 10658-10668
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Tidskriftsartikel (refereegranskat)abstract
- The solar wind energy input into the Earth's magnetosphere-ionosphere system drives ionospheric outflow, which plays an important role in both the magnetospheric dynamics and evolution of the atmosphere. However, little is known about the cold ion outflow with energies lower than a few tens of eV, as the direct measurement of cold ions is difficult because a spacecraft gains a positive electric charge due to the photoemission effect, which prevents cold ions from reaching the onboard detectors. A recent breakthrough in the measurement technique using Cluster spacecraft revealed that cold ions dominate the ion population in the magnetosphere. This new technique yields a comprehensive data set containing measurements of the velocities and densities of cold ions for the years 2001-2010. In this paper, this data set is used to analyze the cold ion outflow from the ionosphere. We found that about 0.1% of the solar wind energy input is transformed to the kinetic energy of cold ion outflow at the topside ionosphere. We also found that the geomagnetic dipole tilt can significantly affect the density of cold ion outflow, modulating the outflow rate of cold ion kinetic energy. These results give us clues to study the evolution of ionospheric outflow with changing global magnetic field and solar wind condition in the history.
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| 25. |
- Li, Kun, et al.
(författare)
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Estimating the Kinetic Energy Budget of the Polar Wind Outflow
- 2018
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Ingår i: Journal of Geophysical Research - Space Physics. - : AMER GEOPHYSICAL UNION. - 2169-9380 .- 2169-9402. ; 123:9, s. 7917-7929
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Tidskriftsartikel (refereegranskat)abstract
- Ionospheric outflow from the polar cap through the polar wind plays an important role in the evolution of the atmosphere and magnetospheric dynamics. Both solar illumination and solar wind energy input are known to be energy sources of the polar wind. However, observational studies of the energy transfer from these two energy sources to the polar wind are difficult. Because of their low energy, polar wind ions are invisible to regular ion detectors onboard a positively charged spacecraft. Using a new technique that indirectly measures these low-energy ions, we are able to estimate the energy budget of the polar wind. Our results show that solar illumination provides about 10(7) W of the kinetic energy of the polar wind, in addition to the energy transferred from the solar wind with a maximum rate of about 10(8) W. The energy transfer efficiency of solar illumination to the kinetic energy of the polar wind is about 6 to 7 orders of magnitude lower than that of the solar wind. Moreover, daily and seasonal changes in the orientation of the geomagnetic dipole axis control solar illumination over the polar cap, modulating both energies of the polar wind and energy transfer efficiencies from the two energy sources.
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| 26. |
- Retino, A., et al.
(författare)
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Cluster observations of energetic electrons and electromagnetic fields within a reconnecting thin current sheet in the Earth's magnetotail
- 2008
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 113:A12
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Tidskriftsartikel (refereegranskat)abstract
- We study the acceleration of energetic electrons during magnetotail reconnection by using Cluster simultaneous measurements of three-dimensional electron distribution functions, electric and magnetic fields, and waves in a thin current sheet. We present observations of two consecutive current sheet crossings where the flux of electrons 35 127 keV peaks within an interval of tailward flows. The first crossing shows the signatures of a tailward moving flux rope. The observed magnetic field and density indicate that the flux rope was very dynamic, and a comparison with numerical simulation suggests a crossing right after coalescence of smaller flux ropes. The second crossing occurs within the ion diffusion region. The flux of electrons is largest within the flux rope where they are mainly directed perpendicular to the magnetic field. At the magnetic separatrices, the fluxes are smaller, but the energy spectra are harder and electrons are mainly field aligned. Reconnection electric fields E-Y similar to 7 mV/m are observed within the diffusion region, whereas in the flux rope, EY are much smaller. Waves around lower hybrid frequency do not show a clear correlation with energetic electrons. We interpret the field-aligned electrons at the separatrices as directly accelerated by the reconnection electric field in the diffusion region, whereas we interpret the perpendicular electrons as trapped within the flux rope and accelerated by a combination of betatron acceleration with nonadiabatic pitch-angle scattering. Our observations indicate that thin current sheets during dynamic reconnection are important for in situ production of energetic electrons and that simultaneous measurements of electrons and electromagnetic fields within thin sheets are crucial to understand the acceleration mechanisms.
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| 27. |
- Sjöström, B, et al.
(författare)
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A method for the preparation of submicron particles of sparingly water-soluble drugs by precipitation in oil-in-water emulsions. I. Influence of emulsification and surfactant concentration
- 1993
-
Ingår i: Journal of Pharmaceutical Sciences. - 0022-3549 .- 1520-6017. ; 82, s. 579-583
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we present a method for the synthesis of small particles of poorly water soluble drug substances using emulsions. In the first place, the drug is dissolved in an organic solvent and a water soluble surfactant is dissolved in water. Secondly, these two solutions are mixed to form an emulsion, where the organic solution is emulsified into small droplets in the aqueous phase. The action of the surfactant is partly to decrease the interfacial tension between the water and the organic solution, thus increasing the ease of emulsification, and partly to stabilize the droplets formed against aggregation, or coalescence. The final step in the process is to remove the organic solvent by evaporation in doing which the drug precipitates and one particle is formed in each droplet. If the surfactant is sufficiently effective in stabilizing the particles formed against coagula--tion, we have a suspension of small spherical drug particles. In this paper we use a model system consisting of cholesteryl acetate and toluene. Particles down to 50 nm were obtained by this method. The sizes of the particles were found to be dependent on the surfactant concentration and the emulsification energy.
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| 28. |
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| 29. |
- Stenius, P, et al.
(författare)
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Nonionic hydrophilic surfaces: adsorption and interactions
- 1990
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Ingår i: Croatica Chemica Acta. - 0011-1643 .- 1334-417X. ; 63, s. 501-516
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Tidskriftsartikel (refereegranskat)abstract
- An overview is given of recent studies of nonionic, hydrophilic surfaces formed by the adsorption surfactants or surface active polymers. Hydrophobic surfaces can be easily hydrophilized by the adsorption of nonionic surfactants or block copolymers containing hydrophobic chain segements; the cooperative interaction between the hydrocarbon moieties contributes more to the free energy of adsorption than the interaction with the hydrophobic surface. Hydrophilic layers are also readily formed on hydrophilic surfaces provided specific interaction between the hydrophilic end groups and the surface creates a sufficiently hydrophobic surface so that a second layer can bed formed through cooperative interaction. The temperature dependence of the interaction forces between layers of surfactants can be closely correlated with their phase equilibria with water. In order to prevent protein adsorption the surface should be neither charged nor hydrophobic; it is shown that, accordingly, protein adsorption is extremely low on poly ethylene oxide-covered surfaces.
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| 30. |
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| 31. |
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| 32. |
- Virtanen, S. M., et al.
(författare)
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Age at introduction of new foods and advanced beta cell autoimmunity in young children with HLA-conferred susceptibility to type 1 diabetes
- 2006
-
Ingår i: Diabetologia. - Natl Publ Hlth Inst, Dept Hlth Promot & Chron Dis Prevent, Helsinki 00300, Finland. Tampere Univ, Tampere Sch Publ Hlth, FIN-33101 Tampere, Finland. Tampere Univ Hosp, Res Unit, Tampere, Finland. London Sch Hyg & Trop Med, Dept Epidemiol & Populat Hlth, Med Stat Unit, London WC1, England. Finnish Canc Registry, Helsinki, Finland. Univ Helsinki, Dept Publ Hlth, Helsinki, Finland. : SPRINGER. - 0012-186X .- 1432-0428. ; 49:7, s. 1512-1521
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Tidskriftsartikel (refereegranskat)abstract
- Aims/hypothesis: Evidence for the role of infant feeding in the development of beta cell autoimmunity is inconsistent. We set out to study the effects of breastfeeding and of age at introduction of supplementary foods on the development of beta cell autoimmunity. Subjects and methods: A prospective birth cohort of 3,565 infants with HLA-DQB1-conferred susceptibility to type 1 diabetes was recruited between 1996 and 2001 from two university hospital areas in Finland. Blood samples were collected at 3- to 12-month intervals to measure antibodies against islet cells, insulin, glutamate dehydroxylase and islet antigen 2. The families kept a record on the age at introduction of new foods, and for each visit completed a structured dietary questionnaire. The endpoint was repeated positivity for islet cell antibodies together with at least one of the other three antibodies. Results: The overall or exclusive duration of breastfeeding was not associated with the risk of developing the endpoint. An early age at introduction of fruits and berries (<= 4 months) was related to increased risk of developing positivity for the endpoint (hazard ratio [95% CI] for earliest tertile 2.02 [1.03-3.95] and for midtertile 1.97 [1.06-3.64] compared with latest tertile > 4 months). Also, introducing roots between 3 and 3.9 months (midtertile) was related to increased risk of the endpoint (hazard ratio [95% CI] for the earliest tertile 1.04 [0.57-1.90] and for midtertile 1.82 [1.19-2.79] compared with latest tertile). These associations were independent of several putative socio-demographic and perinatal confounding factors. Conclusions/interpretation: Our findings suggest that an early age at introduction of fruits and berries and roots associates independently with beta cell autoimmunity, contradicting earlier findings from smaller birth cohort studies.
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