Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China

An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium. The nutrient budget was created for a control and a fertilized treatment which had been fertilized with; 830 kg ha-1 nitrogen, 408 kg ha-1 phosphorus and 736 kg ha-1 potassium as NPK fertilizer during six consecutive years. Results showed that fertilization had contributed to a 20% significantly larger tree biomass. The results also indicated a higher nutrient content in the fertilized treatment than in the control. Depending on nutrient and treatment, the nutrients in understory vegetation accounted for 11-17 % of the total amount of nutrients in the biomass. The main part of the nutrients in the eucalypt ecosystem was found in the mineral soil (85-97%). Over time nutrients decreased in the soil and instead accumulated in the biomass. Furthermore, the results indicated that significant amounts of nitrogen and potassium in the fertilized treatment had leached out. Phosphorus had instead accumulated in the soil. The results also indicated more organic matter and available nutrients in the soil probably due to higher amounts of nutrients and biomass in the fertilized treatment. More organic matter and available nutrients in the soil could lead to improved soil conditions with higher water holding capacity and increased nutrient retention. Fertilization could therefore have a long-term positive effect on the soil leading to a higher productivity.Ett ökat behov av träråvara i Kina har lett till att stora arealer avsatts för plantager med snabbväxande eukalyptus. Plantageskogsbruk med eukalyptus är ofta förknippat med en intensiv skötsel med bland annat gödsling. Genom en ökad förståelse för gödslingens effekter och var näringsämnena ackumuleras skulle ett mer hållbart skogsbruk kunna uppnås. I denna studie skapades en näringsbudget för alla biomassa- och markkomponenter i ett gödslingsförsök med Eucalyptus urophylla. De inkluderade näringsämnena var kväve, fosfor och kalium. Näringsbudgeten skapades för en kontroll och en gödslad behandling där den gödslade behandlingen hade mottagit; 830 kg ha-1 kväve, 408 kg ha-1, fosfor och 736 kg ha-1 kalium i form av NPK-gödsel under en sexårsperiod. Resultaten visade att gödslingen hade bidragit till en 20% signifikant större mängd trädbiomassa. Dessutom indikerade resultaten att den gödslade behandlingen hade ett högre näringsinnehåll jämfört med kontrollen. Beroende på näringsämne och behandling stod näringsämnena i undervegetationen för 11-17% av den totala mängden näringsämnen i biomassan. Huvuddelen av näringsämnena i eukalyptus-ekosystemet återfanns i mineraljorden, (85-97%). Resultaten indikerade på att mängden 4 näringsämnena i marken sedan försökets start hade minskat och istället ackumulerats i biomassan. Vidare indikerade resultaten att signifikanta mängder kväve och kalium i den gödslade behandlingen hade lakats ut. Fosfor hade istället ackumulerats i marken. Resultaten indikerade även på en ökning av mängden organiskt material och växttillgängliga näringsämnen i marken, antagligen till följd av mer näringsämnen och biomassa i den gödslade behandlingen. En ökad mängd organiskt material och växttillgängliga näringsämnen skulle kunna leda till förbättrade markförhållanden med högre vattenhållande förmåga och ökad näringshållande kapacitet. Gödsling skulle därmed kunna ha en långsiktigt positiv effekt på marken vilket skulle kunna leda till en högre produktivitet

Site demand adaption and production potential for birch in Gävleborg County

Large amounts of birch-timber are imported to Sweden, from particularly the Baltic States, since the domestic production can’t support the pulp industry. The goal of this study was to show the potential of birch and the area’s most suitable for birch production. The study was limited to Gävleborg County. Using site characteristics, site index (SI) for birch was estimated on all National Forest Inventory plots in Gävleborg County. Based on these estimations the site characteristics that gave the highest production for birch was found. To find the highest producing (m3sk ha-1 yr-1) birch sites in Gävleborg County and their size, a GIS-model divided in three classes was created. The birch production was also compared with the production-showing tree species (pine or spruce) on the plot to find the areas where birch best could match their production. The sites where birch had the highest production were low altitude and mesic sites with rich field layer type and slopes, in the southern parts of Gävleborg County. When birch was compared with pine and spruce, the sites where birch best could match their production were: low altitude and mesic sites with poor field layer type and slopes. Compared with pine, birch produced better in the southern parts of Gävleborg County, but that was not the case when comparing birch with spruce. The GIS-analysis showed that 15,4 % of all forested land qualified in class 1, the best class. In class 2, 57,4 % of the forested land was placed, and 27,2 % in class 3 with the lowest production.Vårt mål med den här studien var att visa att det finns alternativ till trädslagen gran och tall i det svenska skogsbruket. Det finns redan idag ett behov av björk till industrin och därför kändes det passande att skriva om vilka ståndorter som bäst lämpar sig för björkproduktion. Även ämnet ståndortsanpassning är väldigt aktuellt i nuläget och förhoppningsvis kan vårt arbete ge vägledning om vilka marker som björk lämpar sig bäst på. Detta arbete är gjort inom kursen kandidatarbete i skogsvetenskap på jägmästarprogrammet, SLU. Vi vill rikta ett tack till Ulf Johansson, försöksledare på Tönnersjöhedens och Skarhults försöksparker, för hjälp med att förstå regressionsmodellen, Mats Högström, Institutionen för skoglig resurshushållning, för all hjälp med GIS-analysen samt vänner och familj för givande diskussioner och korrekturläsning

The graded redefined assessment of strength sensibility and prehension: reliability and validity.

Abstract With the advent of new interventions targeted at both acute and chronic spinal cord injury (SCI), it is critical that techniques and protocols are developed that reliably evaluate changes in upper limb impairment/function. The Graded Redefined Assessment of Strength Sensibility and Prehension (GRASSP) protocol, which includes five subtests, is a quantitative clinical upper limb impairment measure designed for use in acute and chronic cervical SCI. The objectives of this study were to: (1) establish the inter-rater and test-retest reliability, and (2) establish the construct and concurrent validity with the International Standards of Neurological Classification of Spinal Cord Injury (ISNCSCI), Spinal Cord Independence Measure II (SCIM), and the Capabilities of Upper Extremity Questionnaire (CUE). The study protocol included repeated administration of the GRASSP to a cross-section of individuals with tetraplegia who were neurologically stable (n=72). ISNCSCI, CUE, and SCIM assessments were also administered. Two assessors examined the individuals over a 7-day period. Reliability was tested with intra-class correlation coefficients; construct validity was established with agreement/discordance analysis between the GRASSP and ISNCSCI sensory and motor items; and concurrent validity was tested with Spearman correlation coefficients. Inter-rater and test-retest reliability for all subtests within the GRASSP were above the hypothesized value of 0.80 (0.84-0.96 and 0.86-0.98, respectively). The GRASSP is about 50% more sensitive (construct validity) than the ISNCSCI when defining sensory and motor integrity of the upper limb; the subtests showed concurrence with the SCIM, SCIM self-care subscale, and CUE. The strongest concurrence to impairment was with self-perception of function (CUE) (0.57-0.83, p\u3c0.0001). The GRASSP was found to demonstrate reliability, construct validity, and concurrent validity for use as a standardized upper limb impairment measure for individuals with tetraplegia

Mitochondrial and plastidial COG0354 proteins have folate-dependent functions in iron–sulphur cluster metabolism

COG0354 proteins have been implicated in synthesis or repair of iron/sulfur (Fe/S) clusters in all domains of life, and those of bacteria, animals, and protists have been shown to require a tetrahydrofolate to function. Two COG0354 proteins were identified in Arabidopsis and many other plants, one (At4g12130) related to those of α-proteobacteria and predicted to be mitochondrial, the other (At1g60990) related to those of cyanobacteria and predicted to be plastidial. Grasses and poplar appear to lack the latter. The predicted subcellular locations of the Arabidopsis proteins were validated by in vitro import assays with purified pea organelles and by targeting assays in Arabidopsis and tobacco protoplasts using green fluorescent protein fusions. The At4g12130 protein was shown to be expressed mainly in flowers, siliques, and seeds, whereas the At1g60990 protein was expressed mainly in young leaves. The folate dependence of both Arabidopsis proteins was established by functional complementation of an Escherichia coli COG0354 (ygfZ) deletant; both plant genes restored in vivo activity of the Fe/S enzyme MiaB but restoration was abrogated when folates were eliminated by deleting folP. Insertional inactivation of At4g12130 was embryo lethal; this phenotype was reversed by genetic complementation of the mutant. These data establish that COG0354 proteins have a folate-dependent function in mitochondria and plastids, and that the mitochondrial protein is essential. That plants retain mitochondrial and plastidial COG0354 proteins with distinct phylogenetic origins emphasizes how deeply the extant Fe/S cluster assembly machinery still reflects the ancient endosymbioses that gave rise to plants

Rehabilitation of hand function after spinal cord injury using a novel handgrip device: a pilot study

BackgroundActivity-based therapy (ABT) for patients with spinal cord injury (SCI), which consists of repetitive use of muscles above and below the spinal lesion, improves locomotion and arm strength. Less data has been published regarding its effects on hand function. We sought to evaluate the effects of a weekly hand-focused therapy program using a novel handgrip device on grip strength and hand function in a SCI cohort.MethodsPatients with SCI were enrolled in a weekly program that involved activities with the MediSens (Los Angeles, CA) handgrip. These included maximum voluntary contraction (MVC) and a tracking task that required each subject to adjust his/her grip strength according to a pattern displayed on a computer screen. For the latter, performance was measured as mean absolute accuracy (MAA). The Spinal Cord Independence Measure (SCIM) was used to measure each subject's independence prior to and after therapy.ResultsSeventeen patients completed the program with average participation duration of 21.3 weeks. The cohort included patients with American Spinal Injury Association (ASIA) Impairment Scale (AIS) A (n = 12), AIS B (n = 1), AIS C (n = 2), and AIS D (n = 2) injuries. The average MVC for the cohort increased from 4.1 N to 21.2 N over 20 weeks, but did not reach statistical significance. The average MAA for the cohort increased from 9.01 to 21.7% at the end of the study (p = .02). The cohort's average SCIM at the end of the study was unchanged compared to baseline.ConclusionsA weekly handgrip-based ABT program is feasible and efficacious at increasing hand task performance in subjects with SCI

The Stromal Processing Peptidase of Chloroplasts is Essential in Arabidopsis, with Knockout Mutations Causing Embryo Arrest after the 16-Cell Stage

Stromal processing peptidase (SPP) is a metalloendopeptidase located in the stroma of chloroplasts, and it is responsible for the cleavage of transit peptides from preproteins upon their import into the organelle. Two independent mutant Arabidopsis lines with T-DNA insertions in the SPP gene were analysed (spp-1 and spp-2). For both lines, no homozygous mutant plants could be detected, and the segregating progeny of spp heterozygotes contained heterozygous and wild-type plants in a ratio of 2∶1. The siliques of heterozygous spp-1 and spp-2 plants contained many aborted seeds, at a frequency of ∼25%, suggesting embryo lethality. By contrast, transmission of the spp mutations through the male and female gametes was found to be normal, and so gametophytic effects could be ruled out. To further elucidate the timing of the developmental arrest, mutant and wild-type seeds were cleared and analysed by Nomarski microscopy. A significant proportion (∼25%) of the seeds in mutant siliques exhibited delayed embryogenesis compared to those in wild type. Moreover, the mutant embryos never progressed normally beyond the 16-cell stage, with cell divisions not completing properly thereafter. Heterozygous spp mutant plants were phenotypically indistinguishable from the wild type, indicating that the spp knockout mutations are completely recessive and suggesting that one copy of the SPP gene is able to produce sufficient SPP protein for normal development under standard growth conditions

HELA STADEN - En kvalitativ studie om hur Göteborgs stad försöker motverka segregationen.

Syftet med studien var att genom en kvalitativ ansats undersöka hur Göteborgs stad arbetar för att minska boendesegregationen i staden. Vi undersökte två områden, Hammarkullen och Frihamnen, som på två olika sätt försöker motverka segregationen och skapa social blandning. Vi intervjuade sex personer som arbetar för områdenas utveckling och övergripande med segregationsfrågor i staden. Vi använde oss av en teoretisk referensram bestående av begreppen makt, etnicitet och diskriminering, social exkludering, klass och kapital, gentrifiering, grannskapseffekter och stigberoende. Studien visade på hur staden försöker motverka segregation genom att bygga blandade upplåtelseformer och i Frihamnen även ha olika hyresnivåer för olika inkomstgrupper. Det fanns en större vilja till nytänkande i segregationsfrågor i den centrala staden än i utsatta områden. Resultaten indikerade även på att det krävs fler insatser än nybyggnation för att bryta utanförskapet i staden. I båda områdena fanns en risk för undanträngning av de med lägst inkomst. Medelklassens perspektiv visade sig vara det centrala för planering av nya bostäder. För att motverka segregationen krävs att politiken tar ett större ansvar och ställer krav på marknaden