Grass/clover silage for growing/finishing pigs – effect of silage pre-treatment and feeding strategy on growth performance and carcass traits

This study evaluated the influence of feeding strategy and grass/clover silage pre-treatment on pig growth performance and carcass traits. In total, 128 pigs weighing 30–110 kg were fed either a commercial control feed or received silage in a pellet (SP) or in a total mixed ratio (TMR) containing chopped silage (SC) or intensively treated silage (SE). Silage replaced 20% of dietary crude protein content (g/kg). Diet affected weight gain (P = 0.001), with pigs fed the SP diet showing best overall growth performance. Pigs fed the SC diet had the lowest weight gain (P = 0.001), while pigs fed the SE diet performed similarly to those fed the control diet. Carcass weight and dressing percentage differed between the diets (P = 0.016 and P = 0.018), but there was no difference in lean meat content (P = 0.832). The results show satisfactory growth performance and carcass traits, indicating that silage can replace other protein sources in growing/finishing pig diets

Domestic Heating with Solar Thermal : Studies of Technology in a Social Context and Social Components in Technical Studies

Research in solar heating has traditionally focused solely on increasing the system efficiency by improving the technical components. In this thesis the technical methodology and system boundaries are widened to connect the technical aspects with market actors that are highly influential on the implementation of solar technology. The research was focused on how social aspects can be brought into technical studies to improve the understanding of solar heating, and how solar thermal technology can be optimized in a larger energy system. Both heat storage and different system solutions have been investigated. The thesis is built on a number of sub-projects exploring different aspects of solar heating. Improved components and system configurations may result in higher fractional energy savings and thereby make solar energy go from a marginal contribution to be the main energy supplier. Both components and systems are considered in this thesis. The solar heating technology has been shown to work well, also in unique system solutions. Technical possibilities with medium-sized stores for single-family houses and seasonal stores for residential areas are presented. Methods to bring studies of technology and actor studies together are also proposed; domestic hot water use has been modelled based on time-use data, while a multifaceted market situation, in which new system solutions must find their way, has been described by the solar and pellet industries. The complexity of assessing installation and use of a particular heating system in relation to the overall energy system is also discussed. Overall, this thesis shows that successful use of solar heating does not only come down to proper technical solutions, but also depends on the interaction between technology and market actors. A widened perspective, including the social context in which the heating system appears, is then essential. This thesis constitutes a step in that direction

Accountability in the public sector : Managing demands by introducing middle managers

Krav på ansvarstagande för offentliga chefer har ökat under de senaste åren, och detta har i sin tur lett till ökat krav på offentliga chefer som dessutom får ta allt mer ansvar. De behöver också lägga ner allt mer av sin arbetstid på att arbeta med just ansvar. Dessa ökade krav är dock inte jämnt fördelade över organisationens chefer. Därför har ansvaret blivit stort för de chefer som ansvarstagandet faller på. Syftet med denna studie är att bidra till en ökad förståelse för ansvarstagande i offentlig sektor. Genom att i praktiken undersöka hur offentliga chefer utkrävs på ansvarstagande samt hur en offentliga organisation internt hanterar krav på ansvarstagande hoppas vi kunna bidra till en ökad förståelse kring begreppet ansvarstagande. Utifrån vårt syfte är två forskningsfrågor formulerade för att med hjälp av dessa kunna besvara syftet med studien.Studien som genomförts är kvalitativ med en abduktiv ansats. Till studien har det tillämpats ett hermeneutiskt synsätt för att kunna förstå och tolka det insamlade empiriska materialet. Det empiriska materialet har samlats in genom semistrukturerade intervjuer som genomfördes med nio respondenter vid en enhet vid Jönköpings kommun. Vi har intervjuat en högre chef, fyra enhetschefer och fyra mellanchefer som arbetar vid samma enhet. Detta för att med hjälp av respondenternas svar kunna fastställa hur en offentlig organisation och dess chefer utkrävs på ansvarstagande och internt hanterar krav på ansvarstagande.Den insamlade empirin har sedan satts i relation till den vetenskapliga litteratur som vi använt oss av i den teoretiska referensramen. Den teoretiska referensramen har utvecklats med hjälp av tidigare litteratur och behandlar tre huvudområden vilka är styrning i offentlig sektor, att förstå ansvarstagande och mellanchefer. Denna teori har sedan använts för att problematisera och analysera det empiriska materialet. Detta har i sin tur mynnat ut i slutsatserna för studien.I studien framkommer det att de undersökta cheferna kopplar begreppet ansvarstagande till ansvar och därigenom även till deras arbetsbeskrivningar. Cheferna utkrävs på så sätt på ansvarstagande genom de olika ansvarsförhållandena som kräver att de utför vissa arbetsuppgifter och sköter vissa ansvarsområden och därmed genomsyrar ansvarstagandet deras arbete. Trots de hinder som kan uppkomma för mellanchefer fungerar mellancheferna i denna organisation som en avlastning för enhetscheferna och underlättar därmed kravet på ansvarstagande som ligger på enhetscheferna.Demands of accountability for public managers have increased in recent years which have resulted in increased demands on public managers, who must take more responsibility. Therefore, they must devote more of their working hours to work with responsibility. However, these increasing demands are not evenly distributed among the organization’s managers. Thereby the responsibility has become heavy for the mangers who deal with accountability. The purpose with this thesis is to generate knowledge about accountability in public sector. By examining how public managers are pressed for accountability and how an organization internally manage demands of accountability, we hope to contribute to an increased understanding around the concept of accountability. Two research questions are formulated to help us answer the purpose with the thesis.The study is conducted by means of qualitative method where we apply an abductive approach. It has applied a hermeneutical perspective to interpret and understand the collected empirical material. The empirical material has been collected through semi-structured interviews with nine respondents at a unit at Jönköpings kommun. We have been interviewing a senior manager, four unit mangers, and four middle managers who work within the same unit. With help from the respondents answers we would like to determine how public managers are pressed for accountability and how an organization internally handle demands of accountability.The collected data has been related to the academic literature which we used in the theoretical framework. The theoretical framework has been developed by using former literature and discusses three major topics, which are public sector governance, understanding accountability and middle managers. This theory has then been used to problematize and analyze the empirical material. All the above have led to the conclusions of this study.In this study, it appears that the examined mangers connect the concept accountability to responsibility and therefore to their job descriptions. The managers are pressed for accountability through their accountability relationships which demand that they perform their working tasks and manage their responsibilities, and thereby accountability permeates their work. Despite the obstacles that can appear for middle managers the middle managers in this organization work as a relief for the unit managers and thereby they ease the demand of accountability, which are lying on the unit managers.This thesis is written in Swedish

Chalmersutbildning kan ge h\uf6gre l\ue4rarstatus

L\ue4raryrket beh\uf6ver en uppv\ue4rdering och stora pensionsavg\ue5ngar samt sv\ue5righeter att konkurrera om studenter till l\ue4rarutbildningen kr\ue4ver \ue5tg\ue4rder och nyt\ue4nkande. Chalmers vill d\ue4rf\uf6r starta \ue4mnesl\ue4rarutbildning i data, fysik, kemi, matematik och teknik s\ue5 att studenten kan f\ue5 b\ue5de en l\ue4rarexamen och en ingenj\uf6rsexamen, skriver bland andra Samuel Bengmark, programansvarig f\uf6r Chalmers l\ue4rarutbildning

Three dimensional mathematical modelling of pronuclei migration for the mouse

It is still an open question when the orientation of the embryonic-abembryonic axis of the mouse embryo is laid down. The two most explicit symmetry breaking events for the egg are the extrusion of the second polar body and the sperm entry. The main question addressed in this paper is what happens between the sperm entering the egg and fusion of the two pronuclei. Orientation of the apposing pronuclei probably plays a decisive role in the polarity of the developing embryo. In order to shed some lights on this intriguing question, a mathematical model that describes the pronuclei dynamics have been constructed in the form of a stochastic differential equation. The model concerns pronuclei migration from the time of the sperm entry to the fusion and spatial orientation of this fusion. The methodology consists of using stacks of confocal microscopy time-lapse images of the pronuclei migration together with statistical methods to identify realistic parameters in the model. Given different angles between the sperm entry and the position of the second polar body, the final model is then used to produce distributions of orientations of the meeting positions between the pronuclei. However, the main result is the suggested model itself which describes the main features of the migration. The fitted model is based on two forces of attraction. Migration is directed towards the centre but also towards the other pronucleus. Parameter values corresponding to the size of these forces are estimated from data of both eggs treated with a microtubule inhibitor and untreated eggs. Simulations from the model with the different model parameters are accomplished and distributions of meeting positions are plotted. These simulated distributions could for instance be used as initial value distributions for future models of egg cleavage

Three dimensional mathematical modelling of pronuclei migration for the mouse

It is still an open question when the orientation of the embryonic-abembryonic axis of the mouse embryo is laid down. The two most explicit symmetry breaking events for the egg are the extrusion of the second polar body and the sperm entry. The main question addressed in this paper is what happens between the sperm entering the egg and fusion of the two pronuclei. Orientation of the apposing pronuclei probably plays a decisive role in the polarity of the developing embryo. In order to shed some lights on this intriguing question, a mathematical model that describes the pronuclei dynamics have been constructed in the form of a stochastic differential equation. The model concerns pronuclei migration from the time of the sperm entry to the fusion and spatial orientation of this fusion. The methodology consists of using stacks of confocal microscopy time-lapse images of the pronuclei migration together with statistical methods to identify realistic parameters in the model. Given different angles between the sperm entry and the position of the second polar body, the final model is then used to produce distributions of orientations of the meeting positions between the pronuclei. However, the main result is the suggested model itself which describes the main features of the migration. The fitted model is based on two forces of attraction. Migration is directed towards the centre but also towards the other pronucleus. Parameter values corresponding to the size of these forces are estimated from data of both eggs treated with a microtubule inhibitor and untreated eggs. Simulations from the model with the different model parameters are accomplished and distributions of meeting positions are plotted. These simulated distributions could for instance be used as initial value distributions for future models of egg cleavage