A conditional marker gene allowing both positive and negative selection in plants

Selectable markers enable transgenic plants or cells to be identified after transformation. They can be divided into positive and negative markers conferring a selective advantage or disadvantage, respectively. We present a marker gene, dao1, encoding D-amino acid oxidase (DAAO, EC 1.4.3.3) that can be used for either positive or negative selection, depending on the substrate. DAAO catalyzes the oxidative deamination of a range of D-amino acids. Selection is based on differences in the toxicity of different D-amino acids and their metabolites to plants. Thus, D-alanine and D-serine are toxic to plants, but are metabolized by DAAO into nontoxic products, whereas D-isoleucine and D-valine have low toxicity, but are metabolized by DAAO into the toxic keto acids 3-methyl-2-oxopentanoate and 3-methyl-2-oxobutanoate, respectively. Hence, both positive and negative selection is possible with the same marker gene. The marker has been successfully established in Arabidopsis thaliana, and proven to be versatile, rapidly yielding unambiguous results, and allowing selection immediately after germination

Pirate stealth or inattentional blindness?:the effects of target relevance and sustained attention on security monitoring for experienced and naïve operators

Closed Circuit Television (CCTV) operators are responsible for maintaining security in various applied settings. However, research has largely ignored human factors that may contribute to CCTV operator error. One important source of error is inattentional blindness--the failure to detect unexpected but clearly visible stimuli when attending to a scene. We compared inattentional blindness rates for experienced (84 infantry personnel) and naïve (87 civilians) operators in a CCTV monitoring task. The task-relevance of the unexpected stimulus and the length of the monitoring period were manipulated between participants. Inattentional blindness rates were measured using typical post-event questionnaires, and participants' real-time descriptions of the monitored event. Based on the post-event measure, 66% of the participants failed to detect salient, ongoing stimuli appearing in the spatial field of their attentional focus. The unexpected task-irrelevant stimulus was significantly more likely to go undetected (79%) than the unexpected task-relevant stimulus (55%). Prior task experience did not inoculate operators against inattentional blindness effects. Participants' real-time descriptions revealed similar patterns, ruling out inattentional amnesia accounts

Genetic variation in competition traits at different ages and time periods and correlations with traits at field tests of 4-year-old Swedish Warmblood horses

For many years, the breeding value estimation for Swedish riding horses has been based on results from Riding Horse Quality Tests (RHQTs) of 4-year-olds only. Traits tested are conformation, gaits and jumping ability. An integrated index including competition results is under development to both get as reliable proofs as possible and increases the credibility of the indexes among breeders, trainers and riders. The objectives of this study were to investigate the suitability of competition data for use in genetic evaluations of horses and to examine how well young horse performance agrees with performance later in life. Competition results in dressage and show jumping for almost 40 000 horses from the beginning of the 1960s until 2006 were available. For RHQT data of 14 000 horses judged between 1988 and 2007 were used. Genetic parameters were estimated for accumulated competition results defined for different age groups (4 to 6 years of age, 4 to 9 years of age and lifetime), and for different birth year groups. Genetic correlations were estimated between results at RHQT and competitions with a multi-trait animal model. Heritabilities were higher for show jumping than dressage and increased with increasing age of the horse and amount of information. For dressage, heritabilities increased from 0.11 for the youngest group to 0.16 for lifetime results. For show jumping corresponding values increased from 0.24 to 0.28. Genetic correlations between competition results for the different age groups were highly positive (0.84 to 1.00), as were those between jumping traits at RHQT and competition results in show jumping (0.87 to 0.89). For dressage-related traits as 4-year-old and dressage competition results the estimated genetic correlations were between 0.47 and 0.77. We suggest that lifetime results from competitions should be integrated into the genetic evaluation system. However, genetic parameters showed that traits had changed during the over 35-year period covered due to the development of the sport, which needs to be considered in future genetic evaluations

Symbiosis constraints : strong mycobiont control limits nutrient response in lichens

Symbioses such as lichens are potentially threatened by drastic environmental changes. We used the lichen Peltigera aphthosa-a symbiosis between a fungus (mycobiont), a green alga (Coccomyxa sp.), and N2-fixing cyanobacteria (Nostoc sp.)-as a model organism to assess the effects of environmental perturbations in nitrogen (N) or phosphorus (P). Growth, carbon (C) and N stable isotopes, CNP concentrations, and specific markers were analyzed in whole thalli and the partners after 4 months of daily nutrient additions in the field. Thallus N was 40% higher in N-fertilized thalli, amino acid concentrations were twice as high, while fungal chitin but not ergosterol was lower. Nitrogen also resulted in a thicker algal layer and density, and a higher δ13C abundance in all three partners. Photosynthesis was not affected by either N or P. Thallus growth increased with light dose independent of fertilization regime. We conclude that faster algal growth compared to fungal lead to increased competition for light and CO2 among the Coccomyxa cells, and for C between alga and fungus, resulting in neither photosynthesis nor thallus growth responded to N fertilization. This suggests that the symbiotic lifestyle of lichens may prevent them from utilizing nutrient abundance to increase C assimilation and growth

Analys av specifik vikt i hund- och katturin

Det säljs och används refraktometrar speciellt anpassade till katturin då katturin påstås vara mer refraktär än urin från andra djurslag. Orsaken till varför eller om det behövs är inte ordentligt utredd eller ifrågasatt, men studier visar att specifika kattrefraktometrar ger systematiskt lägre värden för den specifika vikten än övriga refraktometrar. Syftet med denna studie var att undersöka om det finns anledning att analysera specifik vikt i urin (USG) hos katt och hund med olika refraktometrar. Parade katt- och hundprover (42 av vardera djurslaget) med snarlik USG (± 0,002) analyserades avseende specifik vikt mätt med tre olika refraktometrar, uppvägd vikt med våg och osmolalitet. Skillnaden för vardera parameter inom paren jämfördes för att upptäcka eventuella systematiska skillnader mellan katt- och hundurin. Kattrefraktometern gav systematiskt lägre USG än övriga refraktometrar för urinproverna från både hund och katt. Det fanns ingen signifikant eller systematisk skillnad gällande vägd vikt av urinen (p = 0,31) inom de parade hund och katturinproven. Urinproven från katt vägde inte mindre än prover från hund med snarlik specifik vikt (± 0,002). Katturinen hade däremot signifikant högre osmolalitet (p < 0,01) än hundurinen, vilket talar för att katter har fler små partiklar i urinen jämfört med hund. Baserat på dessa resultat finns det ingen anledning att använda specifika kattrefraktometrar för analys av urinspecifik vikt hos katt.Today specially made cat refractometers are being sold and used because it is suggested that urine from cats is more refractive than urine from another species. If a special cat refractometer is needed, and in that case why, is not properly investigated or questioned. Studies have shown that cat refractometers give a systematically lower urine specific gravity than other refractometers. The aim of this study was to investigate whether it is necessary to use different refractometers when analyzing urine specific gravity in urine from cats compared to dogs. Urine samples from cats and dogs (n = 42 for each species) were paired based on similar urine specific gravity (± 0.002) and specific gravity measured with refractometers, weighed weight and osmolality were analyzed. The difference between the cat and the dog in each pair of samples was compared to detect possible systematical differences between urine from cats and from dogs. The cat refractometer gave systematically lower values for urine specific gravity than other refractometers for both cat and dog urine. There was no significant or systematically difference between the species for weighed weight of the urine of the paired samples (p = 0,31). The urine samples from the cats did not weigh less than the urine samples from the dogs. However, the cat urine samples had significant higher osmolality than the dog urine samples (p < 0,01), which indicates that the cats have more and smaller particles in the urine compared to the dogs. Based on the results from this study there is no motive for using a special cat refractometer when analyzing urine specific gravity in cats

Ekologisk och konventionell mjölk

Ekologiska livsmedel blir allt mer populära och försäljningen och efterfrågan har ökat de senaste åren. Matens kvalitet och näringsinnehåll och hur den produceras blir allt viktigare för konsumenten, och debatten kring ekologiska produkter är ständigt pågående. Ekologisk mjölk utgör en stor del av den ekologiska livsmedelsförsäljningen. Det ökande intresset för ekologiska livsmedel gör det intressant att studera hur produktionssystemet påverkar vik-tiga egenskaper hos livsmedlet, såsom hållbarhet, smak och näringsinnehåll. Syftet med detta arbete var att beskriva skillnaden mellan ekologisk och konventionell mjölk. Arbetet är en litteraturstudie och kommer att ta upp allmänna fakta om ekologiska livsmedel, ekologisk produktion och en fördjupning på mjölk. I fördjupningen beskrivs mjölkens sammansättning, vad som skiljer ekologisk och konventionell mjölk med avse-ende på näringsinnehåll och sensoriska egenskaper, och vilka faktorer som påverkar detta. Resultaten baserar sig på vetenskapliga publikationer som ser till skillnader mellan ekolo-gisk och konventionell mjölk. Den främsta skillnaden mellan den ekologiska och konventionella mjölken är samman-sättningen av fettsyror där den ekologiska mjölken ofta innehåller mer fleromättade fetter, omega-3 fettsyror och en högre kvot mellan omega-3 och omega-6 fettsyror. Den största bidragande faktorn till detta är utfodringen som i den ekologiska djurhållningen består av högre andel grovfoder. Mer omättade fettsyror skulle kunna betyda risk för oxidation och därmed sämre hållbarhet. Det finns inga vetenskapliga studier som tyder på skillnader i smak mellan ekologisk och konventionell mjölk. Eftersom skillnaden mellan den ekologiska och konventionella mjölken i de flesta fall är mycket liten, är det svårt att rekommendera det ena eller andra alternativet sett ur ett kvali-tets- och näringsmässigt perspektiv. Med hänsyn taget till aspekter rörande djurhållningen kan ekologisk mjölk vara ett alternativ för att bidra till bättre djurvälfärd.Organic foods become increasingly popular and sales have increased during recent years. The quality of food and how it is produced is becoming increasingly important for the consumers, and there is an ongoing debate associated to organic products. Organic milk and dairy products constitute a large part of the organic food sales. The increased interest in organic food makes it relevant to study how the organic production affects important properties e.g. shelf life, sensory properties and nutritional quality. The purpose of this report was to describe the differences between organic and conven-tional milk. This work is a literature study and will address general facts related to organic food, organic production and a more detailed survey on milk. It will describe the milk composition, investigate differences in the composition and sensory properties of milk, and the factors that may influence upon this. The result is based on scientific publications fo-cusing on differences between organic and conventional milk. The main difference between organic and conventional milk is related to the composi-tion of fatty acids. Organic milk often contains more polyunsaturated fatty acids, omega-3 fatty acids and a higher ratio of omega-3 to omega-6 fatty acids. The largest contributing factor to this is the difference in feed between the two production systems. In organic farming, the feed consists of higher proportions of fresh grass and roughage. More unsatu-rated fatty acids in organic milk could mean a risk for oxidation and thus shorter shelf life. There is no study that shows differences in taste between conventional and organic milk. The difference between the organic and conventional milk is in most cases very small, which makes it difficult to recommend one or the other option from a nutritional or quality perspective. Organic milk can be an alternative contributing to better animal welfare

Avelsindex för de svenska köttraserna

Syftet med det projekt, som redovisas i denna rapport, var att ta fram underlag för att konstruera ett sammanvägt avelsindex för de svenska köttraserna. I rapporten redovisas det konstruerade indexet och de beräkningar som låg till grund för det. Avelsindexet består av tre delindex: modersindex, produktionsindex och födelseindex. Modersindex är uppbyggt av de maternella indexen för kalvningsförmåga och tillväxt från födelse till 200 dagar. I produktionsindex ingår indexen för slakttillväxt, fettgrupp och formklass. Födelseindex utgörs av indexet för kalvningsförmåga som en egenskap hos kalven. Indexen för de enskilda målegenskaperna vägs i avelsindexet samman med relativa vikter beräknade för varje målegenskap som produkten av det ekonomiska värdet och antalet diskonterade uttryck. De ekonomiska värdena för målegenskaperna beräknades med hänsyn till värdet av ett genetiskt framsteg i respektive egenskap. Antalet möjliga kalvningar och antalet slaktade djur i olika generationer och under olika år beräknades och diskonterades till betäcknings-/semineringstidpunkten. Synpunkter från rasföreningarna om en önskad profilering av de olika raserna med avseende på produktions-, moders- respektive kalvningsegenskaper beaktades också och de relativa vikterna i avelsindexet är anpassade till avelsmålen för respektive ras. Syftet har här varit att tillmötesgå respektive rasförenings önskemål om rasens plats i ett system med korsningsavel och avelsindexet har utvecklats med tydliga profiler som faderras (charolais) med hög tillväxt och goda direkta kalvningsegenskaper respektive moderras (hereford) med tyngdpunkt på maternell kalvningsförmåga samt mjölkavkastning