Den största akuta risken inom dricksvattenförsörjningen är vattenburen smittspridning. Dricksvattenrelaterad smittspridning förekommer i störst utsträckning i utvecklingsländer med dåliga sanitära förhållanden. Under 2000-talet har de nordiska länderna drabbats av flertalet dricksvattenburna sjukdomsutbrott vilket har lett till att mikrobiella föroreningar uppmärksammats som ett problem även i Norden. För att säkerställa att det dricksvatten som distribueras är av god mikrobiologisk kvalitet krävs att säkerhetsbarriärerna i vattenverket är tillräckligt effektiva för alla typer av mikrobiella föroreningar. Vissa mikroorganismer har uppmärksammats som mer tåliga mot olika desinfektionsmetoder, till exempel klorering, än vad som tidigare varit känt.

The goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press.

GE Healthcare operates in Uppsala (Sweden) and develops systems, equipments and medium to purify medical substances. Discussions with the local authority concerning planed far-reaching changes and upgrades of the biological process techniques for sewage management, aroused the question about revising the terms of permit for the activity. Therefore it seemed necessary to evaluate a newly installed biological process technique, which is the background of this thesis. The evaluated biological treatment process was built in 2003 and consists of a biological reactor filled with moving bed carriers with a high surface area for biological growth. At the time of the project the biological wastewater treatment plant consisted of a flow equalization facility and two following parallel biological processes; a biological reactor with moving bed carriers and a tower trickling filter.The aim of this thesis was to survey the function of the biological reactor with respect to the reduction of organic matter.

Dairy farming in Uganda provides a source of food, employment and income. Previous studies have revealed high frequencies of bovine mastitis, a costly disease for the dairy farmer. The aims of this study were to investigate the bacteriological panorama in milk from udder quarters with clinical (CM) and subclinical mastitis (SCM) and to determine the antimicrobial susceptibility in staphylococcal isolates. Further, we intended to establish the prevalence of subclinical mastitis and to investigate some environmental factors and animal properties that might influence the frequency of mastitis. For CM, farmers made contact with the members of this study when recognizing an animal with CM.

The quality of bread wheat is a large subject to study. The quality rests on two legs. The first one is the inheritance of specific characters, which can be influenced through plant breeding and type of cultivar. The other one is the environmental influences, such as crop rotation, nutrition, harvest and storage. The latter factors are possibly to affect through cultivation practices, while other factors are not possible to influence on for the grower, such as seasonal changes of weather and the soil content.

This bachelor thesis is intended to gather the knowledge and experimental data on the winter wheat crop production relevant for Swedish conditions, with focus on sowing time, row spacing and seed rate. This essay is a literature study with a minor component based on interviews with farmers producing winter wheat. The work is divided into a background part where basic knowledge of winter wheat physiology, development and environment interactions are described and one part where results of field trials studies are presented. Optimal date of sowing winter wheat depends on annual weather variations. Because it is difficult to forecast the weather the choice of sowing date should be based on weather statistics, production experience and previous results depending on sowing date.

Mastitis in dairy cows is an emerging and challenging disease in the tropics, including India. Nation-wide reports suggest that the incidence of clinical mastitis varies from 3.94% to 23.25%, and for subclinical mastitis from 15.78% to 81.60%. In Assam, a northeastern province of India, dairy is an essential part of the mixed farming system that exists in the state, but the milk yield is far below domestic standards. In 2009-2010, International Livestock Research Institute (ILRI) and local associates started to develop a training program for local farmers in Assam, in order to enhance the informal bovine dairy sector in and around Guwahati, India. The project continued until mid-2013.

Sammanfattning Kisel (Si) är det näst vanligaste ämnet (drygt 25 %) i berggrunden. Bara en del av detta är tillgängligt som monokiselsyra, den form i vilken kisel är upptagbart för växter. Jordens kiselinnehåll är beroende av bergets vittring. Mycket höga halter av kisel återfinns i naturen i vulkaniska substrat (pimpsten innehåller drygt 66 % Si och scoria närmare 47 % Si), i diatomit (ett mineral bestående av resterna från encelliga kiselhaltiga alger, s.k. diatoméer) innehållande 66 % Si, scoria approximatly 47% Si), in diatomite (a mineral consisting of the remainings of single celled algae, diatoms containing < 40 % Si) and in some clays (30-60% Si).

Trenden i byggbranschen är att efterfrågan på täta, energisnåla byggnader ökar. Passivhus och andra lågenergikonstruktioner blir vanligare och vanligare. Riskerna med att bygga in organiskt material som trä i dessa konstruktioner har fått branschen att börja titta på alternativa material. Lättbetong är ett material som både har bärande och isolerande egenskaper. Dessutom är det inte organiskt vilket gör det okänsligt för mikrobiell påväxt.

Vatten är ett livsmedel som vi kommer i kontakt med dagligen. För att inte råka ut för sjuk-domar och infektioner renas dricksvattnet på vattenverken, främst för att reducera antalet patogener, d.v.s. sjukdomsframkallande mikroorganismer. Man brukar prata om tre grupper mikroorganismer i vattenrening; bakterier, virus och parasiter. Dessa grupper är vitt skilda i många avseenden och reduceras därför olika bra av olika reningssteg.

At seed-growing the aim is to produce a commodity with high germination capacity, good soundness and purity, and also slight admixture of seeds from other species. The capacity of germination and the vigour of the seeds may become impaired in consequence of mechanical damage, infection of diseases, growth of mould, attacks of vermin, high drying temperature, secret germination, sprouting in the ears etc. The germ belongs to the outer and most unprotected parts of the seed, and consequently this is much exposed. Even quite sound seeds can instantaneously have low capability of germination. It can be due to the fact that the seeds are in rest of germination, i.e.