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Initial experiments evaluated the impact of hematocrit on a bird’s ability to adapt to stress and what physiological mechanisms occurred to maintain oxygen carrying capacity (OCC). A final experiment was conducted to obtain proteomic evaluation of protein expression in monocytes of unstressed broilers. In initial experiments, ACTH treatment was applied to hematocrit separated broilers. Experiments evaluated effects of ACTH on broilers with low (19 to 22%, Experiment 1; 18-21%, Experiment 3), high (25 to 28%, Experiment 1; 24 to 27%, Experiment 3) or non-selected hematocrit levels (Experiment 2 and 3). After 4 d of ACTH, all treated birds had significantly increased (P < 0.1) pCO2, HCO3-, and corticosterone levels, indicating as stress raises pCO2, HCO3- must rise to maintain acid base balance. Birds not selected for hematocrit had significant drops in pO2 when given ACTH. Broilers compensate for low OCC through release of red blood cells from storage sites, indicated by decreases in organ hemoglobin and increases in hematocrit and blood hemoglobin when birds are given ACTH. Accelerated red blood cell formation does not appear to occur, because erythropoietin decreases following administration of ACTH to non-selected birds. ACTH induced stress, increased hemoglobin and hematocrit only in birds with low or non-selected hematocrit, suggesting high hematocrit birds prior to stress have an adaptive advantage during stress. Higher hematocrit prior to stress apparently provides ample OCC during stress. Unselected birds appear to require initiation of an inflammatory response to adapt to stress which can be noted by increases in total white blood cell count, monocytes, and heterophils and decreases in lymphocytes. High hematocrit birds appear less susceptible to stress effects by maintaining leukocytes at a constant level, while in non-selected birds lymphocyte percents drop. Proteomics was conducted on avian monocytes to reveal proteins related to immune functions, 3229 proteins were identified, with 46 involved in immune functions of professional antigen presenting cells. This protein data provides a means of comparing monocytes of stressed and unstressed animals in the future. In conclusion, evaluated hematocrit is advantageous in adaptation to stress through maintenance of high OCC, acid base balance and immune cells.

This thesis seeks to establish the levels of population densities, beyond which excessive pressure of population on land would occur in parts of Owerri Province, Nigeria. These Critical Population Densities are determined using Allan's Model. The results of an original field survey and questionnaire provided the information for calculating land requirement per head of the population, and for estimating the carrying-capacity of land. Certain normative hypotheses relating some variables in agricultural land use to elements of farm structure are tested. Other tests are also performed to determine the relative degree of importance of the variables associated with acreage per head cultivated in the province in 1971. / Thesis / Master of Arts (MA)

A wide range of physical systems are modeled as axially moving strings; such examples are belts, tapes, wires and fibers with applied electromagnetic fields. In this study, we propose a model that describes the motion of a current-carrying conductive string in a lateral magnetic field, while it is being pulled axially. This model is a generalization of past studies that have neglected one or more properties featured in our system. It is assumed that the string is moving with a constant velocity between two rings that are a finite distance apart. Directions of the magnetic field and the motion of the string coincide. The problem is first considered in a static setting. Stability critical values of the magnetic field, pulling speed, and current are shown to exist when the uniform motion (along a string line) of the string buckles into spiral forms. In the dynamic setting, conditions for stability of certain solutions are presented and discussed. It is shown that there is a divergence between the critical values in the linear dynamic and static cases. Furthermore, traveling wave solutions are examined for certain cases of our general system. We develop an approximate solution for a nonlinear moving string when a periodic nonstationary current flows through the string. Domains of parameters are defined when the string falls into a pre-chaotic state, i.e., the frequency of vibrations is doubled. / MS / The modeling and analysis of elastic conductors has applications in areas ranging from manufacturing to particle physics. In this study, we model the motion of a conductive string being pulled (between two rings) while a magnetic field is applied in the lateral direction. This system’s stability is categorized through certain parameters such as the applied magnetic field, speed of pulling, and current flowing through the string. The equilibrium states are also analyzed. When the string has a periodic current, approximate solutions (string shape/orientation) are computed. In this case, we find domains of parameters that give rise to chaos. Wave speeds of traveling wave solutions are also found for certain cases.

The Swedish government is planning to increase the maximum vehicle gross load regulations on parts of the national roads from the present 60 t, for the load carrying capacity class BK1, to 74 t, for the proposed new load carrying capacity class BK4. The initial implementation of the new load carrying capacity class for 74 t vehicles will only regard major highways and important roads, however, at a later stage the plan is to implement the new BK4 class on the full current BK1 road network. The biggest obstacle which arises when implementing these increased traffic loads is insufficient load carrying capacity for the bridges on the road network.   Thus, the objective of this thesis is to examine and analyze the effects of the increased traffic loads on Swedish road bridges. In order to identify the structural effects of the load increase, and draw general conclusions regarding the effects on the bridge network as a whole, a case study with load carrying capacity calculations is carried out on a two-span concrete slab fram bridge at a highway interchange in Värö in western Sweden. The bridge is classified as critical by Trafikverket. The load carrying capacity calculation is carried out using the Swedish standards, in which maximum load values for the axle load, A, and the bogie load, B, is calculated.   The load effects acting on the bridge are calculated using the finite element software BRIGADE/Standard, with input traffic A and B loads amounting to 12 t and 21 t respectively for the new BK4 class and to 12 t and 18 t respectively for class BK1. In addition to the load carrying capacity calculations with BK4 traffic loads, a comparison is carried out between the results obtained when using the axle- and bogie loads from the BK1 versus the BK4 load carrying capacity class in the load carrying capacity calculations.   The load carrying capacity calculations performed on the studied bridge shows that the capacity of the bridge, both in regards to moment and shear force, is insufficient to meet the new, increased, BK4 A/B – requirements. The critical A/B – values for the whole bridge are 17 t and 18 t respectively, to be compared with the required 12- and 21 t limit for the new BK4 load carrying capacity class, thus, making the load carrying capacity of the bridge inadequate. The critical A/B – values appear for the longitudinal shear force load case at the point where the shear force reinforcement over the column support ends. Moreover, the difference between the results obtained when using the BK1 versus the BK4 traffic loads in the calculations were found to be negligible.   Due to the differing properties and characteristics of each individual bridge on the Swedish road network it is difficult to make general statements regarding the effects of the increased traffic loads on the bridge network as a whole. Specific load carrying capacity calculations will need to be performed on each individual bridge in order to evaluate its capability to withstand the new increased BK4 traffic load. However, capacity calculations regarding the BK1 load carrying capacity class can, with sufficient accuracy, be used to evaluate the capability of a bridge to withstand the increased traffic loads in the BK4 load carrying capacity class, thus, making it easier to evaluate the strengthening needs for the bridge network as a whole. / Sveriges regering planerar en utökning av den maximalt tillåtna bruttovikten för fordon på delar av det allmänna vägnätet från den nuvarande begränsningen på 60 t, för bärighetsklass BK1, till 74 t, för den nya föreslagna bärighetsklassen BK4. I det första skedet kommer den nya bärighetsklassen, för fordon med bruttovikt upp till 74 t, bara att implementeras på stora motorvägar och andra ur transportsynpunkt viktiga vägar, men, i ett senare skede finns också planer på att implementera den nya bärighetsklassen, BK4, på hela det nuvarande BK1 vägnätet. Det största problemet som förväntas uppkomma under införandet av de nya, ökade, trafiklasterna är otillräcklig bärighet på vägnätets broar.   Således är målet med denna uppsats att undersöka och analysera effekterna av dessa ökade trafiklaster för broar på det Svenska vägnätet. För att identifiera effekterna, och dra generella slutsatser, gällande denna ökade trafiklast för broarna på det Svenska vägnätet i sin helhet kommer en fallstudie med bärighetsberäkningar utföras på en plattrambro vid trafikplats Värö - en bro som Trafikverket bedömer som kritisk. Bärighetsberäkningen utförs enligt svenska standarder, där maximala tillåtna värden på axellasten, A, och bogielasten, B, beräknas.   Lasteffekterna som verkar på bron beräknas med hjälp finita element programvaran BRIGADE/Standard med trafiklaster, A och B, som uppgår till 12  respektive 21 t för den nya BK4 bärighetsklassen och 12 respektive 18 t för bärighetsklass BK1. Som tillägg till bärighetsberäkningarna med BK4 laster utförs också en jämförelse av resultaten som uppkommer när axel- och bogielasterna från BK1 respektive BK4 används i beräkningarna.    Bärighetsberäkningarna på den studerade bron visar att brons kapacitet, både gällande moment och tvärkraft, är otillräcklig när den belastas med de ökade BK4 trafiklasterna. De kritiska A- och B- värdena för bron är 17 respektive 18 t, värden som skall jämföras med kraven på 12 respektive 21 t för den nya bärighetsklassen BK4 – därmed är brons bärighet otillräcklig. De kritiska A- och B-värdena för bron uppkommer för lastfallet med longitudinell tvärkraft vid punkten där tvärkraftsarmeringen över mittstödet slutar verka. Jämförelsen mellan beräkningsresultaten som uppkom med trafiklaster enligt BK1 respektive BK4 visade att skillnaden mellan beräkningsresultaten var försumbar.   På grund av de varierande egenskaperna hos varje enskild bro på det Svenska vägnätet är det svårt att dra generella slutsatser gällande effekterna av lastökningen för vägnätet som helhet. Specifika bärighetsberäkningar måste utföras på varje individuell bro för att kunna utvärdera dess kapacitet att klara av de nya, ökade, BK4 trafiklasterna. Emellertid kan bärighetsberäkningar som beträffar bärighetsklassen BK1, med tillräcklig tillförlitlighet, användas för att bedöma en bros möjlighet att motstå de ökade trafiklasterna i den nya bärighetsklassen BK4, vilket förenklar utvärderingen av vilka broar som kräver förstärkning.

published_or_final_version / abstract / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy

<p>Livestock keeping has been the essential source of livelihood in Babati District for many hundreds of years. The traditional ecological knowledge about this semi-arid environment has influenced the general view on livestock management. This essay discusses the measures that are, or could be taken in Babati District to prevent overstocking and overgrazing in the woodlands. With the continuing population density increase also the livestock population grows. More houses and roads are built and the grazing lands diminish. To avoid overgrazing forest management programmes restrict grazing in forests. This additionally decreases availability of grazing land. My conclusion is that minimizing number of livestock is necessary to not exceed carrying capacity of pasture during drought. Hence this is not free from problems since it is traditionally rooted to have a large number of livestock as a buffer of energy and wealth. One solution for both how to prevent overstocking and how to survive with small number of livestock is to practise zero-grazing. Zero-grazing is to keep a small number of healthy big cattle e.g. exotic cows or crossbreeds in stables or tied up. However, when tying cattle on the spot the fact that cattle have four legs is disregarded.</p>

5 pp.

Car seats for smaller children, offers very good protection incase of a collision. Unfortunately for the parents’ sake , these car seats is heavy to handle outside the car. For example back and forth home and short errands around town. In other words, all those times when you decide to just take out the car seat and carry it instead of place the baby in a baby carrier. By analyzing where and how the car seat is being used. How best to carry heavier loads up to about 15 kg as a car seat with the child can weigh and by taking into account the child ’s and the parents anatomy. This work led to a concept on how this problem can be solved. Various technical principle solutions have been developed and evaluated. The chosen solution has then been further developed by various design approaches where form and expression has been the important part. The main body of the new solution is a softer inner which you lifts out when you leave the car. The baby sits in a carrier that the parent carries in front of their body. Remaining in the car is a chair-like base with ”click” fasteners that lock the softer part in place when it´s placed in the car, with the baby in it. The major benefits of solving it this way is that the baby is carried in front of the body without oblique loaded lifting on the spine. While the solution also itself weighs several pounds less than the current car seats. It also frees the parents both hands by carrying the child this way. All this leads to a gentler living for the parents.

The purpose of the report was to enhance the understanding of logistics within dairy production by investigating if theories of logistics concerning inventory functions and inventory management methods can be applied to dairy production, and if those theories can be used to analyze the costs for materials management. The research question was: What kind of inventory functions and inventory management methods are used within dairy production? The objective of the report was formulated as: To investigate if logistics theories concerning materials management can be used to analyze the costs of fodder inventory? Theories concerning inventory functions and inventory management where collected. To see if these theories could be applied to dairy production four interviews were conducted with different dairy production producers. From those four, two were selected for further research. At those two producers more interviews were held and the authors complemented the interviews with document studies. The gathered data where calculated and analyzed. Both inventory functions and inventory management methods were identified and therefore a cost analysis of the warehouse could be made. The findings of the report shows that it is possible to use the theories presented and that they should be used to develop dairy production.