Non-LTE neutral carbon spectral line formation in late-type stars

We present non-Local Thermodynamic Equilibrium (non-LTE) calculations for neutral carbon spectral line formation, carried out for a grid of model atmospheres covering the range of late-type stars. The results of our detailed calculations suggest that the carbon non-LTE corrections in these stars are higher than usually adopted, remaining substantial even at low metallicity. For the most metal-poor stars in the sample of Akerman et al. (2004), the non-LTE abundance corrections are of the order of -0.35...-0.45 dex (when neglecting H collisions). Applying our results to those observations, the apparent [C/O] upturn seen in their LTE analysis is no longer present, thus revealing no need to invoke contributions from Pop. III stars to the carbon nucleosynthesis.Comment: 2 pages, 1 figure. To appear in the Proceedings of IAU Symposium 228 "From Li to U: Elemental Tracers of Early Cosmic Evolution", eds. V. Hill, P. Francois and F. Primas, Cambridge University Press. Replacement with minor textual correction

Expression of mRNA for phospholipase A(2), cyclooxygenases, and lipoxygenases in cultured human umbilical vascular endothelial and smooth muscle cells and in biopsies from umbilical arteries and veins

Arachidonic acid (AA) is released by phospholipase A(2) (PLA(2)) and then converted into vasoactive and inflammatory eicosanoids by cyclooxygenases (COX) and lipoxygenases (LOX). These eicosanoids are important paracrine regulators of vascular permeability, blood flow, local pro- and anticoagulant activity and they play a major role in the local inflammatory response. We have investigated the presence of mRNAs for PLA(2) and for isoforms of COX and LOX in both human endothelial cells (EC) and in human smooth muscle cells (SMC) in culture and in vascular biopsies of human umbilical veins (HUVB) and arteries (HUAB) by using the reversed transcription-polymerase chain reaction (RT-PCR) technique. Results show detectable levels of PLA(2) type IV (cPLA(2)) in cultured EC and SMC and in vascular wall biopsies from HUAB and HUVB. The cultured EC and SMC demonstrate higher levels of both COX-1 and COX-2 with PCR analyses than do vascular wall biopsies from HUAB and HUVB. This indicates a difference in the native expression of COX-1 and COX-2 in cultures of EC and SMC compared to that in biopsies from intact vessel walls. The EC and SMC in culture do not express mRNA for 5-LOX, that was, however, expressed in the vascular wall biopsies. This speaks in favour of a constitutive, i.e, in vivo expression of 5-LOX in SMC in the vascular wall of both umbilical vein and arteries. Thus results from in vitro studies of constitutive COX and LOX expression in EC and vascular SMC in culture cannot simply be extrapolated to represent in vivo conditions

Predictability modulates the affective and sensory-discriminative neural processing of pain

Knowing what is going to happen next, that is, the capacity to predict upcoming events, modulates the extent to which aversive stimuli induce stress and anxiety. We explored this issue by manipulating the temporal predictability of aversive events by means of a visual cue, which was either correlated or uncorrelated with pain stimuli (electric shocks). Subjects reported lower levels of anxiety, negative valence and pain intensity when shocks were predictable. In addition to attenuate focus on danger, predictability allows for correct temporal estimation of, and selective attention to, the sensory input. With functional magnetic resonance imaging, we found that predictability was related to enhanced activity in relevant sensory-discriminative processing areas, such as the primary and secondary sensory cortex and posterior insula. In contrast, the unpredictable more aversive context was correlated to brain activity in the anterior insula and the orbitofrontal cortex, areas associated with affective pain processing. This context also prompted increased activity in the posterior parietal cortex and lateral prefrontal cortex that we attribute to enhanced alertness and sustained attention during unpredictability. (c) 2006 Elsevier Inc. All rights reserved.This study was supported by grants from The Swedish Research Council (2003-5810), The family Hedlund Foundation and Karolinska Institutet. The project was finished in the context of Stockholm Brain Institute.info:eu-repo/semantics/publishedVersio

Modeling of Covalent Bonding in Solids by Inversion of Cohesive Energy Curves

We provide a systematic test of empirical theories of covalent bonding in solids using an exact procedure to invert ab initio cohesive energy curves. By considering multiple structures of the same material, it is possible for the first time to test competing angular functions, expose inconsistencies in the basic assumption of a cluster expansion, and extract general features of covalent bonding. We test our methods on silicon, and provide the direct evidence that the Tersoff-type bond order formalism correctly describes coordination dependence. For bond-bending forces, we obtain skewed angular functions that favor small angles, unlike existing models. As a proof-of-principle demonstration, we derive a Si interatomic potential which exhibits comparable accuracy to existing models.Comment: 4 pages revtex (twocolumn, psfig), 3 figures. Title and some wording (but no content) changed since original submission on 24 April 199

Föräldrarnas upplevelse av mötet med anestesisjuksköterskan i samband med barnets operation

Bakgrund: När ett barn opereras finns ett starkt samband mellan föräldrarnas och vårdpersonalens beteende vilket påverkar barnet sätt att hantera den nya miljön och anestesin. Att anestesisjuksköterskan möter barn i alla åldrar ställer höga krav på bemötandet och hur informationen anpassas till dem och deras föräldrar. Syfte: Syftet med studien är att belysa föräldrarnas upplevelse av mötet med anestesisjuksköterskan när deras barn skall sövas inför ett kirurgiskt ingrepp. Metod: Semistrukturerade intervjuer med 14 föräldrar. Materialet analyserades med kvalitativ innehållsanalys. Resultat: Resultatet utmynnade i tre kategorier: Information, Föräldrar på operationssalen och Anestesisjuksköterskans professionalitet. Konklusion: Föräldrarna önskar tydlig information i ett tidigt skede. Anestesisjuksköterskans bemötande upplevs viktig för att lämna över barnet i andras händer. Även en lugn miljö på operationssalen var önskvärt

Distributional Preferences in Adolescent Peer Networks

We study distributional ("social") preferences in adolescent peer networks. Using incentivized choices between allocations for themselves and a passive agent, children are classified into efficiency-loving, inequality-loving, inequality-averse, and spiteful types. We find that pairs of students who report a friendship link are more likely to exhibit the same preference type than other students that attend the same school. The relation between types is almost completely driven by inequality-loving and spiteful types. Further analyses suggest that preference peer networks are mainly formed by selection into the network and, to a smaller degree, by preference transmission. The role of peer networks in explaining distributional preferences goes beyond network composition effects. A low rank in academic performance and a central position within the network relate positively to a higher likelihood of being classified as spiteful. Hence, social hierarchies seem to be correlated with distributional preference types

Bedömning av öl – skumbildning, skumstabilitet och grumlighet.

There are different kinds of foam with varying stability and appearance and a number of factors which affect this. The volume and the stability of the foam are important for the beer industry due to the fact that many consumers find this a measure of quality. There are many different methods for measurement of the physical properties of beer foam. Unfortunately none is used as a standard. A method has been developed for measuring foam due to the fact that none of the methods were feasible for us. The method is called the Carlsson/Feldt-method and is based on the measurement of drainage time. Measurements have also been made with the Carlsberg-method. The results of these measurements prove that there are differences between the beers of the project. The Carlsson/Feldt method is suitable for measurements of the differences in head retention and foam forming capacity between beers. Besides the measurements of the 22 beers in the project measurements have also been made of two references. The reason for this is to give the reader a view of the results compared to two typical lager beers. The beer haze may be due to a number of different factors and is, with the exception of certain beer types, generally not desirable. Haze measurements have been made of all beers in the project with a turbidity meter. The results show differences between the beer samples. The measurements show that there are differences between the 22 beers in the project both in terms of head retention, foam formation and haze. What causes these differences is not known but hopefully a base has been created for further studies of the barley project. This thesis is part of a collaboration project between SLU in Alnarp and Campus Helsingborg, university of Lund. In this project beers have been brewed from a number of different varieties of barley. These have been grown under different conditions. Measurements of differences in head retention, foam formation and haze between the beers have been made

Resource efficient irrigation : an analysis of barriers and needs for irrigation technology tools in agriculture

Vattenresurserna inom jordbruket förväntas globalt sjunka med 50% inom de närmsta 30 åren visar prognoser. Detta utgör bland det största hotet för livsmedelsförsörjningen i framtiden (Fogelfors, 2015). Utifrån en studie som gjorts i Sverige belyses problematiken att det svenska jordbruket inte är rustade för extremväder, vilket visades vid torkan 2018. Studien hänvisar att det svenska jordbruket är i behov av att implementera nya teknologier för att vara bättre rustade inför torka i framtiden (Campana et al., 2022). Denna studie syftar till att undersöka och analysera de barriärer som påverkar implementeringen av bevattningstekniska hjälpmedel inom jordbruket samt att undersöka om det finns behov för lantbrukare att med teknik avgöra bevattningsbehovet. Barriärerna som skall studeras med hjälp av Barriärsmodellen är lågt ekonomiskt utbyte, bristande kunskap, normer, brist på rådgivning samt tidskrävande. För att analysera lantbrukares behov av bevattningstekniska hjälpmedel tar denna studie även AIDA-modellen till stöd. Genom semistrukturerade kvalitativa intervjuer och med en strukturerad tematiskanalys kom denna studie fram till att de flesta lantbrukare är positivt inställda till bevattningstekniska hjälpmedel men har ibland svårt att se den verkliga nyttan. Anledningen till att lantbrukarna upplevde att de saknade ett behov kan kopplas till de hinder och barriärer till exempel att det ekonomiska utbytet var för lågt, bristfällig rådgivning av ämnet, bristande kunskap, normer i lantbruksbranschen eller att det är tidskrävande. De flesta lantbrukare känner till bevattningstekniska hjälpmedel, men få känner till några återförsäljare på den svenska marknaden. Av studiens resultat går det därför att konstatera att de flesta lantbrukare hamnar i AIDA-modellens första steg, vilket innebär att de har kännedom om att det finns bevattningstekniska hjälpmedel men de finner inget intresse i att fördjupa sig i detta ämne.Forecasts indicate that agricultural water resources are expected to decrease globally by 50% within the next 30 years. This represents one of the greatest threats to future food security (Fogelfors, 2015). A study conducted in Sweden highlights the issue that Swedish agriculture is not prepared for extreme weather, as evidenced by the drought in 2018. The study suggests that Swedish agriculture needs to implement new technologies to be prepared for future droughts (Campana et al., 2022). This study aims to investigate and analyze the barriers affecting the implementation of irrigation technologies in agriculture and to examine whether there is a need for farmers to use technology to determine irrigation needs. The barriers to be studied using the barrier theory model include low economic returns, lack of knowledge, norms, lack of advisors, and time-consuming. To analyze farmers need for irrigation technologies, this study also utilizes the AIDA model. Through semi-structured qualitative interviews and a structured thematic analysis, this study found that most farmers are positively inclined towards new technology but sometimes struggle to see its real benefits. The reasons farmers felt they lacked a need for these technologies could be linked to the obstacles and barriers, such as low economic returns, inadequate advice on the subject, lack of knowledge, norms within the agricultural sector, or that it is time-consuming. Most farmers are aware of irrigation technologies, but few know of any suppliers in the Swedish market. The results of the study indicate that most farmers fall into the first stage of the AIDAmodel, meaning they are aware that irrigation technologies exist but have no interest in delving deeper into the subject

Active contractility in actomyosin networks

Contractile forces are essential for many developmental processes involving cell shape change and tissue deformation. Recent experiments on reconstituted actomyosin networks, the major component of the contractile machinery, have shown that active contractility occurs above a threshold motor concentration and within a window of crosslink concentration. We present a microscopic dynamic model that incorporates two essential aspects of actomyosin self-organization: the asymmetric load response of individual actin filaments and the correlated motor-driven events mimicking myosin-induced filament sliding. Using computer simulations we examine how the concentration and susceptibility of motors contribute to their collective behavior and interplay with the network connectivity to regulate macroscopic contractility. Our model is shown to capture the formation and dynamics of contractile structures and agree with the observed dependence of active contractility on microscopic parameters including the contractility onset. Cooperative action of load-resisting motors in a force-percolating structure integrates local contraction/buckling events into a global contractile state via an active coarsening process, in contrast to the flow transition driven by uncorrelated kicks of susceptible motors.Comment: 15 pages, 4 main figures, 4 supplementary figure