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660 Uppsatser om Suppression techniques - Sida 24 av 44

Cryopreservation of Oocytes : Comparison between the Cryoloop and the Cryopette vitrification techniques

Crypreservation of oocytes is recently being considered to be a valid choice in infertility treatments.Low survival and fertilization rates due to inefficient slow freeze protocols have been the outcome ofmany previous studies done in the field. However, introduction of the vitrification technique and itsapplication in reproductive medicine and to some extent new improved slow freeze protocols haveshown that oocytes can be cryopreserved with successful outcome.In this project the survival rate of oocytes after vitrification with MediCult Vitrification andWarming Media has been studied. Also, a comparison of the carriers Cryoloop (an open system) andCryopette (a closed system) has been performed.A total of 43 oocytes were vitrified and warmed according to MediCult's protocol, of which 21oocytes with Cryoloop and 22 with Cryopette. The cells were post-thaw incubated in a physiologicalenvironment for 24h. During that time the morphology and viability were observed and noted after 2h,over night and after 24h.

Elevers stress : En studie på grundskolans senare år om elevers upplevelser av stress och hur de tror att man kan reducera den

Students? experience of stress is generally considered to be an isolated problem, caused by school work. Students? experience of stress at school can also be affected by exterior influences.This research aims to discover what factors Swedish students, age 13 ? 16, experience as stressful. It also aims to describe how students believe this stress can be reduced.

Den livgivande elden och det livsviktiga bränslet : Bruket av eld och behovet av bränsle på mesolitiska och tidigneolitiska boplatser i Norrland.

Research on Stone Age hunters and gatherers in Norrland has been lively since the 1960s. Central to this research are questions about the organization of society, sedentariness, continuity and resource management. One central part of life in the taiga is the need for fire and fuel. This aspect has been little discussed in conjunction with the mentioned research questions. My goal is to show that the matter of fire and fuel is an important one that needs to be taken in to consideration when discussing Stone Age Norrland and hunter/gatherers.

Är det en anka eller en kanin? - Fildelning som brott eller uppror, rätt eller fel

The purpose of this paper has been to explore how Swedish users of the file-sharing software Direct Connect perceive their own situation and the file-sharing phenomenon. In addition to ascertain what attitudes prevail in the file-sharing culture and what knowledge file-sharers have regarding the relevant Swedish legislation. The questions central to my area of interest were: - Why do file-sharers use the program Direct Connect? - What knowledge do file-sharers have of the relevant legislation in Sweden? - What attitudes prevail in the file-sharing culture? - Is file-sharing behaviour affected by an individuals experience and/or level of knowledge? I compared the results of my survey with earlier surveys done. In addition I compared categories within the file-sharing group such as gender, age, experience and level of knowledge to determine if there were any patterns within or differences between the groups.

Trä och fukt ? Mätmetoder för fuktrelaterade dimensionsförändringar hos trä och deras användbarhet, med två fallstudier inom konservering

This thesis deals with different methods for measuring moisture-related dimensional changes ofwood. Typically relative humidity is measured to determine if the ambient climate around anobject is harmful to it or not. Values between 40 to 65% RH are recommended for hygroscopicmaterials. To know how a wooden object actually reacts to changes in the surroundingenvironment requires methods that involve the object itself. Because of the wood anisotropy,differences in wood structure, finishes and other restraints, it is not always possible to predict themovements.This paper addresses various measurement methods, primarily methods that have been testedin the field of conservation, with examples of their use.

INDIVIDUELLT LÄRANDE I TEAM - En studie av lärstilars inverkan på lärande, effektivitet och prestation

Organizational learning has become more and more important in the last decades as the environment in which organizations exist continues to change rapidly and unexpectedly. In order for organizational learning to happen, the individuals within the organization must learn. Just as different individuals possess different skills, each individual also has their own learning style. As the use of teamwork increases, so does the need for techniques to put high performing teams together and with organizational learning as one of the objectives the question is, how do we maximize learning, efficiency and performance in teams? This study uses a quantitative method to examine how teams, from a course at the Stockholm School of Economics, perform on the individual learning, team efficiency and team performance scale based on the individual learning styles within the team.

På låtsas och på riktigt. Verklighetsnära lärande i Freinetpedagogik och entreprenöriell pedagogik

Structuring education so that students can discover connections between schoolwork and their everyday lives is a crucial task for a teacher. This is especially true in today?s school system that seeks to foster a spirit of lifelong learning, since educational motivation depends on being able to connect to the tasks at hand. In a system where these connections are not present, students will be motivated only by institutional mechanisms such as test results and grades. This leads to them using a number of techniques for ?optimizing the system? by getting maximal results for minimal effort. This essay looks at two pedagogical movements that aim to decrease the gap between schoolwork and students? reality.

Teknisk analys av konst på papper -Exemplifierad genom undersökning av träsnitt

The aim of this bachelor thesis has been to investigate some of the materials present in and onprinted papers which might be suitable for analysis. A brief history of paper making and somepigments were studied after which the theory of some of the available methods for technicalanalysis were summarized. Two works of art on paper were chosen for a closer examination,both are woodblock prints but of different composition and origin. The investigation wasmade to exemplify some of the common techniques applied on works of art. There were twoaims in these examinations.

Droppbevattningens inverkan på kvalitet och kvantitet hos Solanum tuberosum L i jämförelse med konventionell spridarebevattning :

A literature study and a field trial have been carried out in order to investigate the physiological response of potato plants to different soil moisture levels. Higher yield, quality and number of tubers can according to the literature be obtained if constant high soil moisture is kept during major parts of the growing season. A field trial was set up where drip irrigation was used as an alternative to conventional irrigation techniques to maintain high and constant soil moisture. The application of water in the drip irrigated area was monitored and adjusted on a daily basis so that the soil moisture stayed as close as possible to the recommended level. The sprinkle irrigated area was irrigated according to traditional practices with approximately 35 mm every 7th to 10th day depending on the whether.

Tvärvetenskaplig undersökning av textil Broderiet från Tämta kyrka

There are several objects of age whose provenance and history has disappeared with time. The purpose of this thesis is to find out which analyzing methods that gives results and how the different methods can be combined and /or established in each other. The investigations centers around an embroidery, belonging to Tämta church, with unknown origin, use and age. The embroidery is long and narrow with applications in the form of dragons and eagles on a ground of velvet cloth. The dragons and eagles are covered with metal threads.

Ethics and Animal Experimentation in the Laboratory. A Critical Analysis of the Arguments for"Animal Rights"and"Animal Equality"

Growing up as a child, we had a Dog. To us, it was like a means to an end. That is, hunting other animals for food and for protection, with no special care and treatment given to this animal. Butas days passed by I began to witness a wind of change against such actions. I was made to understand that we were committing two crimes-: using the Dog as a means to an end (for hunting and for eating animals).

Comparison of Different Electrophoretic Methods for Haptoglobin Phenotyping and an Investigation in Patients with Abdominal Aortic Aneurysm

Haptoglobin is an acute phase protein with important biological role because of its capacity to bind to haemoglobin. Haptoglobin exists in three major genetic polymorphism types: Hp1-1, Hp2-1 and Hp2-2, the distribution of which has been associated with abdominal aortic aneurysm (AAA), an asymptomatic aortic disease common among men older than 65 years.    Five different electrophoretic methods were tested according to their ability to separate the haptoglobin phenotypes. The detection was based on a produced hemolysate of blood in which haemoglobin binds to haptoglobin thereby forming a complex that can be detected by specific haemoglobin staining using TMB-dihydrochloride and hydro peroxide as substrate resulting in an azure-green color of the bands. Samples from 15 patients who had suffered surgery for not broken AAA, that is more than5.0 cmaortic diameter, and 15 samples from matched controls were analyzed.    Among the five tested electrophoretic methods best migration and separation was seen on the pre-cast agarosgel Hydragel HR on the instrument Hydrasys. The other four methods gave less successful results.

Etik och censur inom internetfiltrering ? En forskningsöversikt

This paper is a research review in the realm of censorship systems andfiltering systems. It applies ethical considerations to the creation of censorshipsystems bringing forward discussion on the ethics of technology with thepurpose of limiting access to information.There is active research being done in the area of automatic content filteringand censorship systems. These are systems that can filter out undesiredmaterial, typically from the Internet, automatically. Used in some nations,many schools and even mandated in some libraries there are many ethicalquestions raised concerning censorship and access to information.Part of the review concerns the level of accuracy of these systems presentedby researchers in the field and the different approaches used. Reviewedarticles centre around automatic content classification and filtering ofpotentially harmful materials with regards to minors while some relate tocensorship technology in a wider sense.Results show a general lack of discussion concerning the ethics of thetechnology in the research reviewed.

Breast cancer stem cells : evidence and contradictory views

This literature study aims to examine the existence of cancer stem cells in breast cancer. The cancer stem cell theory states that there is a hierarchical organization within a tumour, in which a small subpopulation of the cells can initiate new tumours and maintain tumour growth whilst the bulk of the tumour cannot. These tumour initiating cells have shown to possess many characteristics similar to those of adult stem cells, which is why they are often referred to as cancer stem cells. Both cell types have the capacity of asymmetric division and have shown to possess mechanisms of resistance to both apoptosis and cancer drugs. The cancer stem cell theory elucidates many biological aspects such as the heterogeneity of tumours and the relapse of many cancers after what appeared to be successful treatments.

Sjuksköterskors upplevelser och erfarenheter av ofria luftvägar prehospitalt

The purpose of this study was to explore nurses' experiences of obstructed airways in the prehospital work.A qualitative interview study with a descriptive and explorative design was used. The sample consisted of nine registered nurses whereof three were women and six were men, with or without further education and varying length of experience in the ambulance service.Prehospital personnel builds up a vast plan of action based on the emergency information provided by SOS. Simple methods for managing obstructed airways were stated often enough. Problems with obstructed airways are considered so unusual that it never becomes a routine. Several factors affect the identification and managing of obstructed airways, both external factors and the different patient categories are considered important.

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