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Evaluation of Yeast Cell Wall on Early Production Laying Hen PerformanceHashim, Mohammed Malik Hashim 1981- 14 March 2013 (has links)
he influence of two levels of yeast cell wall on phase one laying hen performance was investigated in this study. A total of 75 Lohmann W-36 replacement pullets, 17-weeks-old, were distributed among 75 laying hen cages (1 bird per pen). A total of 3 treatments were sequentially assigned to pens and each treatment had 25 replicates. Feeds were prepared according to the management guide for those birds and a single basal diet was divided into three treatments. First was the control basal diet only with no feed additives. The second was the basal diet supplemented with 250 ppm of yeast cell wall (YCW 250) and the third treatment was the basal diet supplemented with 500 ppm of yeast cell wall (YCW 500). Individual birds per cage served as the experimental unit for this study. Feed and water were offered ad libitum. Data were collected when birds were 21 weeks old and hen day egg production was > 90%.
Treatment YCW 250 resulted in significantly higher egg weight than the control and YCW 500 treatment in the first and second production period and was higher than YCW 500 in the third and fourth production period. Feed consumed per dozen eggs was significantly lower in treatment YCW 500 versus treatment YCW 250, but not significantly lower than the control for the first production period and all treatments were not different from each other for the rest of the study. Average feed consumed per bird per day, and monthly cumulative egg production was not different between treatments. Period feed conversion ratios were lower for the second and fourth period (P = 0.15 and 0.18 respectively). There was no treatment effect on interior egg quality except for yolk color for the YCW 500 treatment in the fourth period which had significantly higher Roche color scores than the YCW 250 treatment. Specific gravity, egg shell thickness, egg shell weight, and percent shell weight were significantly higher in hens fed YCW 500 versus YCW 250. Egg shell breaking force was significantly higher in hens fed YCW 250 versus the control group. Overall, feeding a diet supplemented with yeast cell wall improved laying hen performance and 250 ppm YCW had the most significant influences, particularly with respect to increasing egg weight in early production laying hens.
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Geochemical Diagnostics of Metasedimentary Dark Inclusions: a Case Study from the Peninsular Ranges Batholith, CaliforniaLiao, Kelley 24 July 2013 (has links)
Dark enclaves rich in amphibole and biotite are ubiquitous in granitoid rocks and generally thought to represent fragments of mafic magmas, cumulates or restites. However, magmatic assimilation of metamorphic or sedimentary country rock can also form dark enclaves. To develop criteria for identifying dark enclaves of non-magmatic origin, we investigated dark enclaves from a complete spectrum of light (carbonate- or feldspar-rich) to dark (amphibole-rich, biotite-rich, or composite) enclaves, reflecting progressive thermal and chemical equilibration with host tonalite from the Domenigoni Valley pluton in the Peninsular Ranges Batholith, California. Metasedimentary dark enclaves have a number of major and trace element characteristics that overlap those of literature-compiled igneous dark enclaves. Comparison to modeled igneous differentiation paths shows metasedimentary enclaves can have anomalous CaO and K2O contents for a given SiO2, but other major element systematics may not deviate noticeably from igneous differentiation trends. In addition, the fact that there are literature-compiled mafic enclaves trending towards high K2O and high CaO suggests that not all mafic enclaves are of igneous origin. While the majority of dark enclaves may not be metasedimentary, this work provides some criteria for identifying enclaves should a case of metasedimentary origin arise.
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New developments on preparation of cooled and bunched radioactive ion beams at ISOL-Facilities: the ISCOOL project and the rotating wall coolingPodadera Aliseda, Ivan 07 July 2006 (has links)
Last years have become very productive for the research, construction and development of new facilities devoted to the production of beams with exotic radioisotopes (Radioactive Ion Beams, RIB). These beams are later used for experiments in fields like nuclear physics, atomic physics, astrophysics or medicine, among others. Within this kind of facilities, the ISOL facilities stand out. They are based on the on-line separation of radioactive isotopes produced in nuclear reactions between a target and a high-energy proton beam. The ISOL method was the pioneer for these facilities and it has kept up to now the leadership of RIB facilities. The main reason is ISOLDE, an ISOL facility located at CERN, the largest accelerator complex in the world, where this doctoral thesis has been carried out.The first innovation which is described is the design of an ion trap for the cooling and bunching of RIB's for ISOLDE, the so-called ISCOOL (ISOLDE COOLer). It is an Radio Frequency Quadrupole ion Cooler and Buncher (RFQCB), device based on the Paul traps. In these traps, the ions are confined in the three dimensions by electric fields. The ions are confined on the transverse plane with the pseudopotential well created by the Radio Frequency Quadrupole (RFQ) and focused on the longitudinal axis. At the same time, a gas (normally helium) fills the chamber with a pressure between 10-3 and 10-2 mbar. The collisions between the atoms or molecules of the gas and the ions. In addition, to drive the ions to the extraction of the RFQCB, an axial electric field is created by segmented electrodes. Different voltages are applied to these electrodes in order to choose the shape of the field. The shape can be chosen to create a potential well close to the extraction from the RFQCB in which the ions are accumulated and extracted as bunches, by the fast-switch of the voltages applied to the axial electrodes.The new ISCOOL will be installed as a permanent device of the ISOLDE beam lines.
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p-n junction photodetectors based on macroscopic single-wall carbon nanotube filmsHe, Xiaowei 16 September 2013 (has links)
Single-walled carbon nanotubes (SWCNTs) are promising for use in solar cells and photodetectors because of their strong optical absorption in most of the solar spectrum. There have been many reports about the photovoltaic effect in nanoelectronic devices based on individual SWCNTs, but they have been limited by complicated fabrication and miniscule absorption. There has been a growing trend for merging SWCNTs into micro-and macroscopic devices to provide more practical applications. Here we report the photoresponse of macroscopic SWCNT films with a p-n junction at room temperature. Photovoltage (PV) and photocurrent (PC) due to the photothermoelectric (PTE) effect were observed at the junction, and they were larger by one order of magnitude as compared with their values at the metal-SWCNT interfaces. Various factors affecting PV amplitude and response time have been studied, including junction length, substrate, and doping level. The maximal responsivity we observed was 1V/W with samples on Teflon tape, while a fast response time 80 S was observed with samples on AlN substrates. Hence an optimal combination of photoresponse time and amplitude can be found by proper choice of substrate. It was found that PV increased nonlinearly with increase in n-doping concentration, indicating the existence of an optimal doping level. This result also suggests the possibility to further improve photoresponse by changing p-doping level. Finally, we checked the photoresponse in wide wavelength range (360-900 nm), and PV was observed throughout, indicating that the device could potentially be used as a broadband photodetector.
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Framstam till timmerlastbilAndersson, Staffan, Jansson, Mikael January 2008 (has links)
Examensarbetet har gjorts åt Höglunds flak i Säffle och behandlar en ny framstam till timmerlastbilar. En framstam är ett lastskydd som förhindrar stockarna på en timmerlastbil från att tränga in i hytten vid en kollision. Framstammen används även vid lastning som ett mothåll att slå stockarna emot. Kraven på framstammen från företaget är • Lättare konstruktion • Samma utböjning vid slagprov, ytbelastning och böjbelastningsprovning som nuvarande modell • Billigare eller samma pris som föregående modell • Klara proven enligt SS 2563, SS 2564 • Vara estetiskt tilltalande för kund • Anpassningsbar höjd • Om möjligt få så mycket tillverkning som möjligt till den egna verkstaden Arbetet delades in i två delar där en del är att konstruera plåten och hur denna skall styvas till. Den andra är att konstruera staken som håller upp plåten och tar den största delen av slagkraften. På framstamsplåten togs det fram 2 koncept. Bockningskonceptet. Konceptet består av en aluminiumplåt 6082-T6 som bockats till en L-profil runt kanterna för att styva upp plåten Fyrkantsprofil. Detta koncept består av en fyrkantsprofil i aluminium som nitas fast mot plåten. På staken togs det fram tre koncept. Alla tre är beräknade med att vara i samma material ett höghållfast stål vid namn Domex 650 med en sträckgräns på ca 650Mpa.[5] JL-profilen Är en profil som är lätt att tillverka genom bockning och är lätt att fästa in i både plåten och i rambalken. I-profilen I-balken är gjord med en större fläns mot plåten för att underlätta vid infästning och en mindre fläns på andra sidan för att minska vikten. På grund av att detta inte är en original balk så kommer denna modell att strängpressas. W-profilen W- profil som även denna skulle stängpressas och är även lätt att fästa mot plåten. Den har tagits fram med tanken på en T-balk som sedan stadgats upp med två stycken förstyvningar. Fyrkantröret har en lägre vikt på 19 kg i jämförelse med rör- profilen, detta motsvarar en viktbesparing på 55%. I-profilen klarar att ta upp 0,6kJ mer än Z-profilen samtidigt som den är 23 kg och 23% lättare. / The work is done for the company Höglunds flak in Säffle and aims to develop a new front wall to a timber truck. A front wall is what protects the cabin from the logs in case of a collision. The front wall is also used while loading the truck as a loading fixture to beat the logs against. The requirements for the front wall from the company are: • Easier construction • The same deformation at impact testing, surface testing and bending load as the original. • Cheaper or the same price as the previous model • Withstand the standardization SS 2563, SS 2564 • Be attractive to the customer • Customizable height • If possible, get as much production as possible to the own workshop The work was divided into two parts where one is to make the plate and how to make it rigid. The second is the beams which are going to keep up the plate and takes the greater part of the impact force. Two concepts on the front wall plate, both is of the same material 6082-T6. Bending concept. The concept consists of an aluminium plate which is bended to an L-profile around the edges to rigid up the plate. Square concept. This concept consists of a square tube in aluminium which is riveted firmly against the plate. Three concepts on the beams. All three are estimated to be in the same material Domex 650 JL-profile Is a profile that is easy to manufacture by bending and is easy to mount on both the plate and in the frame beams. I-profile The I-beam is made with a larger flange to the plate in order to facilitate the attachment and a small flange on the other side to reduce weight. However, because this is not an original beam it will be manufactured through extrusion. W-profile W-profile is going to be extruded and is also easy to attach to the plate. It has been developed with the idea of a T-beam which then is stated up with two webs. Of the two plate concepts it was the Square concept which was best suited one. The bending concept was not chosen because the material of the plate was for brittle and couldn’t be bent as much as wanted. The analysis of the plate was made according to the standard SS2563, SS 2564 with a pressure of a certain distance from the base. The FEM analysis at the plate shows that there is no residual deformation, which is the same as the original plate. The square pipe has a lower weight with 19 kg which is 55% lighter compared with the circular pipe profile. The profile is able to take up 0,6 kJ more than the Z-profile and 23kg and 23% lighter
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Reuse of Grey water in Peri-urban areas in Dar es Salaam, Tanzania : Minor Field StudyKocanda, Jakub, Kaguongo, Michael January 2010 (has links)
The purpose of this thesis is to understand and analyse the issues of grey water generation and disposal in peri-urban areas of Dar es Salaam in Tanzania and to propose a suitable solution to which includes designing a treatment system for grey water (water from shower, washing and kitchen). The purification will eliminate the sanitation issues that are brought by exposing untreated grey water to the environment as well save freshwater. This will be implemented with regard to local conditions in Dar es Salaam, Tanzania. Water-borne and vector-borne diseases are mainly brought by untreated grey water, which sadly enough causes thousands of death cases every year in Tanzania. The year between 2004- 2005, 154551 cases of dysentery were reported with 170 deaths. It was also reported, 863488 cases of typhoid with 1167 deaths and last but not least 12923 cases of cholera from with 350 deaths. Deaths that were caused by diarrhoea were also reported, whereby, 90 % of them are children. According to the interviews that were conducted, people would not want to recycle the grey water for example for washing due to socio-cultural context where water is considered dirty even after treatment. They had difficulties in believing that the same dirty grey water can be purified and reused again for various domestic activities. The conducted characterisation of grey water showed the tested grey water has relatively high levels of BOD, basic pH, higher than average values of TSS, relatively low levels of DO, increased salinity and average level of FC. The analyses were performed on the most polluted grey water from every source. The volume of household produced grey water varies strongly, depending on socio-economic situation of the household and type of access to water supply. From estimation, the volume varies approximately between 60 -160 l/day and household for a low income household. Living wall was proposed as grey water treatment system, because of its suitability to the peri-urban settlement and tropical climate. The system consists of concrete boxes placed over each other, filled with inner porous material and planted with plants. The system purifies grey water as it percolates through it and at the same time provides a vertical space for growing plants. The plants for the treatment system were chosen to Typha latifolia and Scirpus species. The plants are growing in Tanzania and are being used for wastewater treatment purposes. The plants are tolerant to increased salinity and can grow in alkaline soil. The cleaning effectiveness of the system was not tested, but only roughly estimated with help of values from a similar treatment system build in Gotland, Sweden. Hence, the reuse of grey water in this geographical location suits best for irrigation in rural and peri-urban areas with potential for agriculture as well as groundwater recharge in the peri-urban and urban areas. Recharging groundwater with treated grey water has a potential to be observed as an indirect and long term reuse of the water as it reconnects in the hydrological cycle.
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Evaluation of RANS turbulence models for flow problems with signigicant impact of boundary layersFurbo, Eric January 2010 (has links)
This master’s thesis was provided by the Swedish Defence Research Agency, FOI. The task is to test several RANS (Reynolds-averaged Navier-Stokes) models on two different case geometries and compare the results with LES and experimental data. The first is two dimensional, constructed for flow separation at a sharp edge. The second is three dimensional and flow separation occurs at a smooth surface. The models tested are implemented in the open source CFD (Computational Fluid Dynamics) program, OpenFOAM. OpenFOAM uses the finite volume method and the SIMPLE algorithm as solution procedure. The main flow features evaluated is the shape, position and size of the flow separation. Most of the models tested have problems describing the complex dynamics of flow separation in these particular cases. In addition to the simulations, the RANS k-epsilon turbulence model is presented and the RANS equations and the equation for the turbulent kinetic energy are derived from the Navier-Stokes equations. The theory behind wall functions is described and these equations together with the equations in the k-epsilon model are compared with the equations implemented in OpenFOAM.
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The Development of System Identification Approaches for Complex Haptic Devices and Modelling Virtual Effects Using Fuzzy LogicTam, Sze-Man Samantha January 2005 (has links)
Haptic applications often employ devices with many degrees of freedom in order to allow the user to have natural movement during human-machine interaction. From the development point of view, the complexity in mechanical dynamics imposes a lot of challenges in modelling the behaviour of the device. Traditional system identification methods for nonlinear systems are often computationally expensive. Moreover, current research on using neural network approaches disconnect the physical device dynamics with the identification process. This thesis proposes a different approach to system identification of complex haptic devices when analytical models are formulated. It organizes the unknowns to be identified based on the governing dynamic equations of the device and reduces the cost of computation. All the experimental work is done with the Freedom 6S, a haptic device with input and feedback in positions and velocities for all 6 degrees of freedom . <br /><br /> Once a symbolic model is developed, a subset of the overall dynamic equations describing selected joint(s) of the haptic robot can be obtained. The advantage of being able to describe the selected joint(s) is that when other non-selected joints are physically fixed or locked up, it mathematically simplifies the subset dynamic equation. Hence, a reduced set of unknowns (e. g. mass, centroid location, inertia, friction, etc) resulting from the simplified subset equation describes the dynamic of the selected joint(s) at a given mechanical orientation of the robot. By studying the subset equations describing the joints, a locking sequence of joints can be determined to minimize the number of unknowns to be determined at a time. All the unknowns of the system can be systematically determined by locking selected joint(s) of the device following this locking sequence. Two system identification methods are proposed: Method of Isolated Joint and Method of Coupling Joints. Simulation results confirm that the latter approach is able to successfully identify the system unknowns of Freedom 6S. Both open-loop experimental tests and close-loop verification comparison between the measured and simulated results are presented. <br /><br /> Once the haptic device is modelled, fuzzy logic is used to address chattering phenomenon common to strong virtual effects. In this work, a virtual wall is used to demonstrate this approach. The fuzzy controller design is discussed and experimental comparison between the performance of using a proportional-derivative gain controller and the designed fuzzy controller is presented. The fuzzy controller is able to outperform the traditional controller, eliminating the need for hardware upgrades for improved haptic performance. Summary of results and conclusions are included along with suggested future work to be done.
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Structural and inhibition studies on UDP-galactopyranose mutaseKarunan Partha, Sarathy 30 March 2011 (has links)
UDP-galactopyranose mutase (UGM) is a flavoenzyme which catalyzes the interconversion of UDP-galactopyranose (UDP-Galp) and UDP-galactofuranose (UDPGalf). UDP-Galf is the active precursor of Galf residues. Glycoconjugates of Galf residues are found in the cell wall of bacteria and on the cell surface of higher eukaryotes. Galf residues have not been found in humans and the fact that they are essential for the growth of pathogenic bacteria makes UGM a potential antibacterial target. In the present study, crystal structures of UGM from Deinocococcus radiodurans (drUGM) in complex with substrate (UDP-Galp) were determined. UDP-Galp is buried in the active site and bound in a U-shaped conformation. The binding mode and active
site interactions of UDP-Galp are consistent with the previous biochemical and mechanistic studies. The mobile loops in the substrate complex structures exist in a closed conformation and Arg198 on one of the mobile loops stabilizes the phosphate groups of the substrate. The anomeric carbon of galactose is 2.8 Å from the N5 of FAD
(in the reduced complex) favorable to form FAD-galactosyl adduct. In addition to substrate complex structures, the crystal structures of drUGM in complex with UDP, UMP, and UDP-Glc have been determined. The mobile loops in all these complexes exist in a closed conformation.
Inhibitors for UGM were identified by ligand-based and structure-based methods. The phosphonate analog of UDP-Galp (GCP) showed only weak inhibition against various bacterial UGMs. The structure of drUGM in complex with GCP provided a basis for its inhibitory activity. Poor stabilization of the phosphate groups by conserved arginines (Arg198 and Arg305) and altered sugar binding mode account for its activity. Novel indole-based (LQ1, LQ6 and LQ10) inhibitors of UGM were identified through
structure-based virtual screening (SBVS) of a chemical library. Inhibition studies also
allowed the identification of an active site aspartic acid that plays role in inhibitor
binding. The structural studies on drUGM provided a basis for understanding substrate
binding to UGM. In vitro enzyme inhibition studies allowed the identification of novel
indole-based inhibitors. The structural and inhibition studies reported here enhance the
understanding of UGM-ligand interactions and will assist in the development of more
potent inhibitors of UGM.
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Evaluation of contact and non-contact lap splices in concrete block masonry specimensAhmed, Kawsar 11 July 2011 (has links)
An experimental program was performed for qualitative and quantitative comparison of the maximum tensile resistance of contact and non-contact lap spliced bars in reinforced concrete block masonry using double pullout and wall splice specimens. A total of 32 specimens were tested, consisting of an equal number of double pullout specimens and full-scale wall splice specimens. Both specimen types had the identical cross-section. Eight replicate specimens for each specimen type were constructed with both contact and non-contact lap splice arrangements. Grade 400 deformed reinforcing bars with a 300 mm lap splice length were provided in all specimens.
The double pullout specimens were tested applying direct tension to the lapped reinforcing bars. The splice resistance and displacement were recorded during testing. All double pullout specimens with contact lap splices developed, as a minimum, the yield strength of the reinforcing bars and generally displayed evidence of a yield plateau. In contrast, the double pullout specimens with non-contact lap splices failed when only 46.1% of the theoretical yield strength of the reinforcing bars was recorded as the maximum splice resistance. The difference between the average value of the tensile resistance in the contact and non-contact spliced bars was identified as being statistically significant at the 95% confidence level.
Wall splice specimens were tested under a four-point loading arrangement with the lapped bars located in the constant moment region. The applied load and specimen deflection were recorded until failure occurred. A numerical analysis was then performed to calculate the maximum resistance of the spliced bars. The specimens with contact lap splices developed the theoretical yield capacity of the reinforcing bars. In contrast, the wall splice specimens with non-contact lap splices developed an average tensile resistance of 78% of the theoretical yield capacity. The difference between the average tensile resistances of the lapped bars in the two splice arrangements was identified as being statistically significant at the 95% confidence level.
On average, the contact and non-contact lap spliced bars in the double pullout specimens developed 8.47% and 41.2% less tensile resistance, respectively, as compared to the wall splice specimens with the identical splice arrangement. Both differences were identified as being statistically significant at the 95% confidence level.
Bond loss between the reinforcing bars and the surrounding grout was identified as the failure mode for both the double pullout and wall splice specimens with contact lap splices. In contrast, bond loss at the masonry block/grout interface was observed along the non-contact lapped bars in both specimen types, as identified by visual observations upon removal of the face shell and the surrounding grout. Based on the test results of the wall splice specimens with non-contact lap splices, a correction factor of 1.5 is suggested when calculating the effective splice length for the non-contact splice arrangement as tested.
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