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331 Uppsatser om Sediment sampling - Sida 19 av 23

Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon

Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques. The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.

Kronandelsrelaskopering - metodoptimering och mätfelsstudie : metodoptimering och mätfelsstudie

I dagens skogsbruk bedöms gallringsbehovet utifrån gallringsmallar som ger rekommendationer baserade på avvägningar mellan biologisk kunskap, ekonomiska faktorer och risker. Gallringsmallarna är anpassade efter tänkta produktionsskogar och kan således vara bristfälliga i andra fall. Därför behövs en effektiv bedömningsmetod som fungerar i både homogena och heterogena bestånd. Studier har visat att tallens (Pinus sylvestris) grönkronandel har påvisad effekt på diametertillväxten och genom att uppskatta denna kan ett direkt mått ligga till grund för bedömning av gallringsbehov, istället för det indirekta måttet grundyta, som nuvarande gallringsmallar är utformade efter. Tanken är att undvika produktionsförluster genom att gallra innan grönkronan hissats upp alltför mycket.

Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.

Förekomst av leukocyter i råsperma hos semingaltar :

Detection of leukocytes in semen from boars is part of the routine control of semen quality. Leukocytes in semen can cause damage to spermatozoa that leads to impaired fertilization. In the artificial insemination (AI) industry there are standard routines for the quality control of the boars and of the neat semen before use. Since 2001, Quality Genetics has not done the leukocyte examination on semen samples from boars which are used for the production of pigs for slaughter. The purpose of this study was to investigate the occurrence of leukocytes in semen from AI-boars. The questions addressed were whether there are boars that have leukocytes in their semen and how frequently it occurs and, moreover, if there are differences between breeds, or even between individuals whose semen was checked before use in AI-dose production compared to those which were not. The study included a total of 135 AI-boars, of which 67 were Hampshire, 35 Yorkshire and 33 Landrace, all belonging to Quality Genetics AI-station in Hållsta.

Analys av konsignationslager : inom tillverkande industri

In this composition, a study of consignment inventory on basis of the factors which are important for implementation and application of consignment inventory are made. Logistics chain from subcontractor to end customer is becoming more complex when the volume of items constantly increases to satisfy the needs of the market. From that perspective, companies had large inventories but today it is a lot of different solutions to streamline inventory management. One way that recently becomes increasingly common is to let the subcontractor fill up the customers stock using different approaches such as VMI (Vendor Managed Inventory). A further step in the evolution can be to make use of consignment inventory where the vendor owns the stock of the customer.

Carbon sequestration in the pastoral area of Chepareria, western Kenya : a comparison between open-grazing, fenced pastures and maize cultivations

Carbon sequestration through restoration of degraded pastoral soils is an advocated way of mitigating global warming, and simultaneously alleviating poverty. An often proposed rehabilitation strategy is fencing of pastures, a method that was introduced to the farmers of Chepareria by the Vi-Agroforestry organization in 1987. The landscape of Chepareria changed from eroded, over-grazed grasslands, to a mixture of open-grazed commons, pastoral enclosures and cultivations. The aim of this study was to investigate (1) if the soil organic carbon (SOC) is higher inside the enclosures than on the open-grazed commons, (2) if SOC is affected by duration of fencing and (3) what effect cultivation of pastures has on the SOC. Estimations of vegetation cover and deep profile (100cm) soil sampling was performed on six clusters containing; (1) open-grazing (OG) (2) 1-5 years of fencing (FENCED(1)), (3) 7-10 years of fencing (FENCED(2)), (4) 15-23 years of fencing (FENCED(3)), (5) maize from OG (A(OG)), (6) maize from fenced pasture (A(FENCED)).

Ett resecentrums betydelse för en stadskärna . : En studie om Kramfors resecentrums funktion och relation till den urbana omgivningen, samt upplevelsen av denna

The purpose of this study is to shed light on and describe Kramfors travel centers function and relationship to the surrounding urban environment, and how this core is experienced by residents and visitors. To do this, the use of the travel center, its relationship to Kramfors city center and the perception of it, as well as possible improvement areas has been studied.This has been examined using a quantitative method by designing a questionnaire and the usage of a research strategy through the implementation of a small-scale survey. Within this a cluster sampling was applied.The result shows that Kramfors travel centers is primarily used for traveling and is used most frequently by the visitors within the study. It is also shown that residents 'primary reason for traveling from the travel center is friends and family, followed by shopping, and that the visitors' primary motive for traveling is friends and family as well, followed by work. The mode of transportation between the travel center and destinations are mainly walking, while the mode of transport between homes and the travel center proves to be the car.

HBTQ-personers upplevelser av vårdmötet

Homo- och bisexuella, transpersoner och queerpersoner (HBTQ) har historiskt sett stigmatiserats och negligerats både globalt och i Sverige nationellt. Individer som inte tillräknats heteronormativet har diskriminerats av samhället generellt, men även inom sjukvård och forskning. Ett resultat av heteronormen är att andra sexuella läggningar och könsidentiteter blir betraktade som onormala. I omvårdnadsarbetet möter allmänsjuksköterskan personer som tillhör HBTQ- gruppen i sitt dagliga arbete, och har därmed ett behov av kunskaper i bemötandet av denna patientgrupp. Syftet med denna studie är att undersöka upplevelser som HBTQ-personer haft i samband med kontakt med hälso- och sjukvårdspersonal i Sverige.

The black-and-white colobus monkeys (Colobus angolensis palliatus) of Diani forest, Kenya : behavioural responses to habitat fragmentation

The loss of habitat is one of the greatest threats to global biodiversity today. Consequences to a species inhabiting fragmented habitats include: group size changes, altered diets and altered foraging behaviours. In my study I observed Colobus anlgolensis palliatus troops living in the forests of Diani, a highly developed area on the Kenyan coast. I looked for differences in behaviours between three troops inhabiting pristine forest patches and three troops inhabiting highly degraded forest areas. I used focal animal sampling with instantaneous sample points.

Sättningar i sulfidjord: uppföljning och utvärdering av sättningars storlek och tidsförlopp, väg 760 i Norrbotten

Sulfidjord anses allmänt vara en problemjord ur geoteknisk synvinkel. I allmänhet är sulfidjord sättningsbenägen och krypsättningar kan bli stora. Sulfidjord betraktas även som problematisk ur ett miljöperspektiv då den i kontakt med syre oxiderar och produkterna av det kan försura mark och vatten. Sulfidjordens sättnings- och krypegenskaper utgör svåra problem vid väg- och järnvägsbyggnad där stora mäktigheter på lösa sediment ofta påträffas. Efter väg 760 i Norrbotten påträffas just ett sådant område på 660 meter med ca 10 meters mäktighet av lösa sulfidsediment i form av silt.

Inneklimatet på ett kontor : Undersökning av inneklimatet vån. G4 stadshuset samt kontor på Ånghammargatan

This report describes an investigation of the indoor climate in two different workspaces. Since we a big part of our lives are staying indoors in artificial environments, and more particularly in our workplaces, we think it would be interesting to do this investigation. The technical solutions for air treatment systems began with simple natural systems without fans and where the thermal rise of the air applied. In modern time is technical air treating systems used to take care of the fresh air supply. This type of units can supply filtered air with the right temperature to the building. Well-functioning ventilation is essential to bring clean fresh air to the room and effectively remove impurities without sound- or draught problems. The indoor climate is relevant for the output capacity.

A comparison of group housing and individual housing for dairy bulls kept for breeding

This study was conducted at VikingGenetics' bull breeding station in Falkenberg, Sweden. The bulls waiting for the results of their progeny testing at this station are either kept in group housing or individual housing. Since both of these housing systems have advantages and disadvantages, it was in the interest of VikingGenetics to know which of these housing systems is the best. The aim of this study was to investigate the welfare of the bulls in these two housing systems through behavioural observations and the use of activity monitors. In the preparations for the study 16 bulls, 8 in each housing system, were chosen.

Påverkas stereotypt vandrande hos amurleopard (Panthera pardus orientalis) vid ökad förutsägbarhet i samband med utfodring?

Stereotypic pacing is frequently observed in captive carnivores, however the underlying causes of this behaviour remain somewhat unclear. One of these possible causes are unpredictable feeding signals, which may give rise to frustration and subsequent pacing. Animal keepers at Nordens Ark had noticed that their Amur leopards had shown stereotypic pacing in connection to the passing of ATVs (All Terrain Vehicles) used by animal keepers primarly when feeding the animals in the park. The aim of this study was to investigate whether the stereotypic pacing of the two Amur leopards at Nordens Ark were affected by the introduction of a signal associated with feeding. The leopards were trained by classical conditioning to associate the sound of a siren with the delivery of food by an animal keeper.

En analys av SCA Skog AB's metod för egenuppföljning av gallringar :

A high quality is highly requested in today?s thinnings, since these are the base for continued value development of the forests. Thinning quality often means a minimization of damages on soil, stems and roots during the cutting. One way to reach a high quality is to set up goals that will be followed up after the cutting is made. Self-checking gives information of the machine drivers work and guarantees the customers a good quality of work.

Metylkvicksilvers toxicitet

Metylkvicksilver (MeHg) är en form av tungmetallen kvicksilver och det är den form som är farligast för djur och människor. Det beror på dess organiska egenskaper som gör att det biomagnifieras genom födokedjan, effektivt absorberas från föda, distribueras till många organ, koncentreras i levande organismer, passerar blod-hjärnbarriären och ackumuleras, samt orsakar skador även vid låga doser. Det har neurotoxiska och immunologiska effekter på djur i alla åldrar, men djur i prenatalperioden är känsligast för exponering av MeHg och kan drabbas av utvecklingsstörningar. Effekterna skiljer sig något mellan hanar och honor, men är även individuella. Dessutom skiljer sig tidpunkter för utveckling hos olika djur och organ är olika känsliga.

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