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53 Uppsatser om Spider trap - Sida 1 av 4

Beteende hos lekvandrande lax i Klarälven ? utvärdering av en fiskfälla

During the migration season in 2013 a study on spawning migrating salmon and the effect of water flow on the behavior was conducted of the salmon at the Forshaga hydropower station in the River Klarälven. The River Klarälven with its nine hydropower plants on the Swedish side, constituting migration obstacles for the migrating salmon. Fortum Generation AB has together with the County Administrative Board restored a salmon trap at the lowermost hydropower station in Forshaga, aiming at making it possible for the salmon to swim into the trap, and thereafter be transported by truck past the power plants and then continue their journey to the spawning grounds on their own. Unfortunately, it is believed that the trap does not work as well as it should. In this study, I focused on salmon position in relation to water flow and if the number of salmon that swam into the fish trap differed between salmon with previous experience of the trap (experienced) and salmon without experience (unexperienced).

Relationen mellan failure trap- strategin, depressiva symptom och alkoholproblematik bland studenter

Syftet med denna studie var att undersöka om den teoretiska modellen failure trap- strategin kan förklara alkoholproblematik och depression bland studenter, samt om strategin kan förklara alkoholproblematik ut-över depression. Vi belyser även om strategin bidrar till det dubbelrik-tade sambandet mellan alkoholproblematik och depression. Deltagare var 358 universitetsstudenter vid ett mellanstort svenskt universitet. Deltagarna svarade på en onlinebaserad enkät rörande depressiva symptom, alkoholvanor och användandet av failure trap- strategin. Data analyserades genom korrelations-och regressionsanalyser.

Inblick i fenomenet webbskrapning

Föreliggande kandidatarbete har till syfte att undersöka fenomenet Webskrapning. Webbskrapnings-program (också kända som Web Wanderers, Crawlers, Spiders eller skrapare) är program som söker igenom webben automatiskt för att extrahera information från webbsidor. Ett exempel på web skrapning är när ett företag samlar in data om prissättningar på en vara eller en tjänst och sen använder informationen för att producera billigare erbjudanden. Detta ger företaget en fördel så att de kan fokusera mera på att marknadsföra sin sida/tjänster. Utöver detta så blir de utsatta företagens servrar också hårt belastade med trafik (skrapning) från ?icke kunder?.

Blood compatibility of biomaterials made of recombinant spider silk

Native spider silk is an attractive lightweight natural polymeric material with a unique combination of strength, extendibility and flexibility. Synthetic, recombinant spider silk is an attractive biomaterial with several possible fields of application. When a foreign material is introduced to blood, this can for example cause unwanted coagulation and complement activation. The aim of this study was to investigate if coatings of heparin or albumin could improve the blood compatibility of films of recombinant spider silk and to develop an initial method to do so. Hypothetically, objects like pacemakers, stents and dental implants could be covered with spider silk films of high blood compatibility to reduce potentially harmful foreign body reactions caused by the immune defense. Increased blood compatibility would likely lead to improvements for both the individual patients and the society thanks to reduced load on healthcare institutions. Our objective was to assess the blood compatibility of both functionalized and non-functionalized recombinant spider silk by evaluating coagulation and activation of the complement system of the immune defense. Coagulation was evaluated visually on glass slides and complement activation was analyzed by measuring the concentration of the complement system mediator C3a in blood samples that had been exposed to the different materials. This study introduces a non-toxic and easy performed method of improving the blood compatibility of recombinant spider silk films by adding a heparin coating. Heparin coated surfaces had statistically significantly higher blood compatibility than uncoated surfaces. The effects of albumin coating of films were less clear compared to the results of heparin coated films. Complement activation could not be evaluated because of high activation in all samples prior contact with the materials that were included in the study..

Inblick i fenomenet webbskrapning

Föreliggande kandidatarbete har till syfte att undersöka fenomenet Webskrapning. Webbskrapnings-program (också kända som Web Wanderers, Crawlers, Spiders eller skrapare) är program som söker igenom webben automatiskt för att extrahera information från webbsidor. Ett exempel på web skrapning är när ett företag samlar in data om prissättningar på en vara eller en tjänst och sen använder informationen för att producera billigare erbjudanden. Detta ger företaget en fördel så att de kan fokusera mera på att marknadsföra sin sida/tjänster. Utöver detta så blir de utsatta företagens servrar också hårt belastade med trafik (skrapning) från ?icke kunder?. Efter att ha genomsökt både akademiska och allmänna källor via informationsinsamling, av denna information så dras slutsatsen att man inte fullt ut kan hindra skrapning av hemsidor. Detta på samma sätt som man inte fullt ut kan hindra någon IT-attack, det finns inga 100 % vattentäta system.

"With great power comes great responsibility" : En studie av teknik och biologi i superhjältefilmer

Vår tids syn på teknik ser vi tydliga spår av i dagens filmer, och kanske framförallt superhjältefilmer. Där använder sig både hjältar och skurkar av avancerad teknik i sin kamp mot varandra. Men även synen på biologi avspeglas i dessa filmer, och det mest intressanta är när dessa ställs mot varandra. Vi har jämfört två av vår tids största hjältar, en som använder sig av teknik och en som har biologiska krafter, för att se vilka likheter och skillnader som finns. Hjältarna det rör sig om är Spider-Man och Batman..

Vattenflödets betydelse för fångster av lekvandrande lax (Salmo salar) och öring (Salmo trutta) : En utvärdering av laxfällan vid vattenkraftverket i Forshaga

Many watersheds have lost stocks of migrating fish species because of the development of hydroelectric plants and other fragmenting barriers. The remaining stocks of migrating Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) in River Klarälven, Sweden are five times smaller compared to one hundred years ago. A fish-trap at the hydroelectric plant in Forshaga has been vital for the continued existence of the stocks. This is the first hydroelectric plant of eight, blocking the way to the spawning grounds. Spawners are collected in the trap for both hatchery and transport by truck upstream and past seven more hydroelectric plants to the spawning grounds, where they are released for possible natural reproduction.


I domstolens fälla? Den Liberala Intergovernmentalismen från Utstationeringsdirektivet till Lavaldomen

This thesis aim to advance the Liberal Integrovernmentalism (LIG) developed byAndrew Moravcsik in order to order to explain how the European Court of Justice (ECJ) can make de facto EU policies diverge from what was originally intended by the Member States. More specifically it describes how the Posting of Workers Directive, Directive 96/71/EC, originally was created to shield certain Member States and their respective systems of regulating the labour market from pressure arising from the posting of workers form low-wage countries inside the EU. However, through a series of cases in the ECJ the de facto policy of the directive has changed and it is now in itself a potential threat against these systems. The Member States now find themselves caught in a ?Joint-Decision Trap?, unable to rectify the situation even though their original agreement has been turned on its head.

Påverkar jordbruk flödet av akvatiska insekter till land? : Effekter av jordbruk på akvatiskt tillflöde till land vid norrländska bäckar

Streams and riparian zone are closely linked by reciprocal flows of energy and nutrients. A large part of the transportation from water to land is in form of emerged aquatic insects. Conversion of land from forest to agriculture can greatly affect aquatic ecosystems, and due to the close link, also affect the adjacent terrestral zone. Investigating how the presence of agriculture in the surrounding area affects amounts of emergent aquatic insects gives an indication on how agriculture, in turn, may affect the terrestral enviroment. The study was preformed alongside ten streams in northern Sweden; five in landscape transformed by agriculture and five in undisturbed forest areas.

Färgval hos blomkrabbspindeln (Misumena vatia) med och utan konkurrens

The colour choice of spiders and the effects of competition on this phenomenon were examined in the laboratory using the sit-and-wait predator goldenrod crab spider (Misumena vatia, (Thomisidae)). This species can  be both white and yellow (could also change colour)  and it was here examined whether individuals preferred to sit on flowers which has the same colouration as their bodies. I found that M.vatia showed preference for flowers that matched their own body colour, but when competition was introduced this preference disappear. It seems, however, that position is a factor that can influences the substrate decisions of M. vatia, where the edge of the flower is preferred..

Klimatfaktorers inverkan på granbarkborrens svärmningsintensitet i Medelpad

The spruce bark beetle (Ips typographhus) is one of the 25 000 species of insects in Sweden, an insect of great economic importance because it can alone terminate forest of high value. During the past decade, insights of climate change received with increasing attention. If the future brings a milder climate in the north and therefore a longer growing season, one would think that it would only affect the forestry to the better? Yet in recent time, outbreaks after storm felling seems to occur more frequently. The Spruce bark beetle ruins millions of cubic meter of Norway spruce (Picea abies) in Sweden alone, with more frequent storm felling and a larger amount of wind thrown threes in the forests there will also be room for an advancing reproduction.

Monitoring and pest control of Fruit flies in Thailand : new knowledge for integrated pest management

Fruit flies (Tephritidae) are serious pests that cause enormous losses for farmers in many countries. The frequent use of insecticides in controlling fruit flies in fruits and vegetable has not resulted in sustainable management of the pest. Problems associated with this complete reliance on chemical control are many residues of insecticides in crops, health problems for farmers, contamination of water and soil, insecticide resistance development and decrease in natural enemy populations. The implementation of control measures that do not imply an added burden to the environment and/or the farmers is urgent. More knowledge about the ecology of fruit flies is the basis for finding new and better ways to control this pest.

Inventering av vecklare i Svenska äppelodlingar

Over the last couple of years, growers, researchers, advisors and plant protection companies have noticed increasing problems with tortricids in Swedish apple orchards. Since the insecticide Gusathion (azinphosmethyl) has been banned (end of 2008; KemI 2008), a further increase of tortricid populations can be expected. In order to get a picture of species composition and population densities among the tortricids, an inventory of seven species, Adoxophyes orana, Archips podana, Archips rosana, Cydia pomonella, Hedya nubiferana, Pandemis heparana and Spilonota ocellana was made in 11 orchards in southern Sweden (Skåne) in 2008. Population densities were estimated by bud sampling (April 20-25), pheromone trapping (May 5-September 22) and assessment of fruit damage (September 9-12). In all orchards A.

Apparently obscure

Through wing pattern, posture and movement, a harmless moth of the family Brenthia imitates an eight-eyed jumping spider. When an octopus of the species Thaumoctopus mimicus sense danger it can alter its appearance to that of a venomous sea snake. They are both drawing attention to themselves. Nevertheless, and because of this, they are protected. The mechanism is called mimicry.

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