In 2011 Manitoba experienced an extreme flood. The operation of the Assiniboine River Diversion resulted in the addition of approximately 1.72 million cubic decameters of water to Lake Manitoba and an increase in water levels to 1.5 m above normal. Although this event resulted damage to farmland and many local homes, it also provided me the unique opportunity to utilize previously impractical methods of bathymetric and substrata distribution analysis in the adjoining Delta Marsh. Combined with satellite imagery taken in 2011 I was able to classify the vegetation classes within the study area and explore the relationship between vegetation distributions and water depth as well as those between water depth and substrata distribution. A seed bank study was carried out to explore the diversity of viable seeds in the area. In addition, satellite imagery taken in 2009 was used to evaluate the effects of the flood event experienced in 2011. / October 2015

Die vorliegende Dissertation beschäftigt sich mit der Herstellung und Charakterisierung von dünnen amorphen Metallschichten. Diese Materialklasse hat durch das Fehlen von klassischen mikrostrukturellen Fehlern wie Versetzungen oder etwa Korngrenzen Vorteile hinsichtlich der mechanischen Belastbarkeit oder beispielsweise Korrosionsbeständigkeit. Die binären Legierungen Ni-Zr und Cu-Ti wurden grundlegend in ihren Phasen-Gefüge-Eigenschaftsbeziehungen insbesondere in Abhängigkeit ihrer Zusammensetzung untersucht. Unter anderem wurden die Oberflächenrauheit und der spezifische elektrische Widerstand bestimmt und im materialwissenschaftlichen Kontext diskutiert. Das Hauptaugenmerk lag auf der Ermittlung der mechanischen Kennwerte wie E-Modul und intrinsische Eigenspannung. Die Kenntnis darüber ist notwendig, wenn in reproduzierbarer Weise Mikroröhren durch Aufrollen aus Dünnschichten dieses Materials hergestellt werden sollen. Eine solche Technologie setzt Eigenspannungsgradienten orthogonal zur Schichtebene voraus, so dass nach Ablösen vom Substrat sich eine Röhrengeometrie durch elastische Relaxation ergibt. In dieser Arbeit wurden die eigenspannungsgenerierenden Effekte in Abhängigkeit des Gefüges und der vorliegenden Phasen analysiert. Die gemessenen konkreten Werte wurden genutzt um erste Röhren gezielt herzustellen. Dabei zeigte sich, dass bereits mit geringem technologischem Aufwand die Röhren sich reproduzierbar und vorhersagbar in ihrer Geometrie fertigen lassen. / This dissertation is addressing the preparation and characterization of thin amorphous metallic films. That material class has its advantages concerning mechanical stability or corrosion resistance due to the lack of classic microstructural defects like dislocations or grain boundaries. Ni-Zr and Cu-Ti as binary alloys were examined thoroughly in their phase-microstructure-property relationships especially in dependency on chemical composition. Beside others the surface roughness and specific electrical resistivity was determined and discussed in material science context. The main focus was on investigation of mechanical characteristic values like Young’s modulus and intrinsic residual stresses. Knowledge on that issue is necessary, when microtubes are to be reproducibly fabricated out of thin films made of these materials. Such a technology requires a stress gradient perpendicular to the layer plane, which leads to a tube geometry after separating it from the substrate due to the effect of elastic relaxation. In the present research the stress generating effects are analyzed with respect to the microstructure and existent phases. The measured actual values were used to produce first test tubes. It is shown, that these tubes can be fabricated in a reproducible and foreseeable manner in geometry even with a low techno-logical effort.

H αλόγιστη απόρριψη των αγροτοβιομηχανικών αποβλήτων στο περιβάλλον προκαλεί σοβαρά προβλήματα παγκοσμίως. Πολλά από αυτά όπως π.χ. τυρόγαλα περιέχουν θρεπτικά συστατικά τα οποία μπορούν να χρησιμοποιηθούν από μικροοργανισμούς προς παραγωγή προϊόντων υψηλής προστιθέμενης αξίας. Στην παρούσα εργασία χρησιμοποιήθηκε ο ζυμομύκητας Kluyveromyces marxianus για την ζύμωση συνθετικού μέσου με λακτόζη συγκέντρωσης ανάλογης με εκείνη του τυρογάλακτος (~5% w/v) προς παραγωγή αιθανόλης. Προσδιορίσθηκαν οι βέλτιστες φυσικοχημικές συνθήκες και τα αποτελέσματα έδειξαν ότι σε pH 7 και 30οC επιτυγχάνεται μέγιστη ταχύτητα ζύμωσης και συγκέντρωση αιθανόλης. Στις ίδιες συνθήκες, μέτρηση του ρυθμού πρόσληψης λακτόζης επισημασμένης με 14C από τον μικροοργανισμό έδειξε ότι αυτός σχετίζεται άμεσα με την κινητική της ζύμωσης. / Τhe indiscriminate disposal of agro waste in the environment causes serious problems worldwide. However, many of them for example whey, contain nutrients which can be used by microorganisms in order to produce products with high value. In this study is being used the yeast Kluyveromyces Marxianus for the fermentation of synthetic substrate of lactose with lactose concentration similar to that of the whey (~5% w/v) for ethanol production. Having determined the optimal physicochemical conditions and the results showed that at pH 7 and 30οC achieved a maximum speed of fermentation and ethanol concentration. Under the same conditions, measuring the rate of uptake of 14C-labeled lactose by the microorganism showed that this is directly related to the kinetics of fermentation

One of the motivating reasons for the development of hydroponics was avoidance of root pathogens. Hydroponics involves growing crops in relatively sterile media, isolated from the underlying soil which may have disease pressure. However, even when hydroponics is coupled with controlled environments such as high tunnels and climate-controlled greenhouses, soil-borne pathogens can enter the growing area and proliferate due to optimal environmental conditions for pathogen growth. Control of root pathogens is difficult and usually achieved through synthetic fungicides since few biocontrol options are available. Compost water extracts (CWE) have recently been gaining the attention of greenhouse growers because they may be a low-cost, environmentally friendly approach to control root disease. CWE are mixtures of compost and water incubated for a defined period of time, either with or without aeration, and with or without additives intended to increase microbial populations, which in turn suppress disease. Much anecdotal, but very little scientific, evidence exists describing CWE effect on suppressing soil-borne pathogens. The present study 1) examined the effect of an aerated CWE on disease suppression at the laboratory scale and in container studies using different soilless substrates, 2) investigated a phenotypic change at the root level caused by CWE that may be associated with disease suppression, and 3) isolated some factors in the production of CWE that affect the ability of a CWE to suppress disease. The common model pathogen-host system of Fusarium solani f.sp. pisi and pea was used to examine CWE-induced disease suppression, with information then being translatable to similar patho-systems involved in greenhouse crop production. In the first study, laboratory-based root growth and infection assays resulted in 100% suppression of F. solani when roots were drenched in CWE. These protected seedlings were then taken to a greenhouse and transplanted into fine coconut coir, watered with hydroponic nutrient solution, and grown for five weeks. At the end of the experiment, 23% of the shoots of the pathogen-inoculated, CWE-drenched seedlings remained healthy while only 2% of the inoculated seedlings without CWE drench remained healthy. All of the roots of the inoculated seedlings developed lesions, even those drenched in CWE. However, 29% of the CWE drenched roots were able to recover from disease, growing white healthy roots past the lesion, while only 2% recovered naturally. A shorter-term container study was conducted in the laboratory to determine the effects of CWE-induced suppression when peas were grown in different substrates and to determine if the hydroponic nutrient solution had an effect on the suppression. Peas were grown in sterilized fine and coarse coconut coir fiber and sand irrigated with water, with a second set of fine coir irrigated with hydroponic nutrient solution. Pea seeds with 20-25mm radicles were inoculated with pathogen and sown directly into CWE-drenched substrate and grown for three weeks. At the end of the experiment, 80%, 60%, 90%, and 50% of the shoots of the inoculated, CWE-drenched seedlings remained healthy when grown in fine coir, coarse coir, sand, and fine coir irrigated with hydroponic nutrient solution, respectively. Nearly 100% of the roots grown in coconut coir substrates again developed necrotic lesions but 83%, 87%, 100%, and 87% grew healthy roots beyond the disease region. The hydroponic nutrient solution had a negative effect on suppression, with a reduction of at least 30 percentage points. Sand demonstrated a natural ability to suppress F. solani. Only 23% of inoculated seedlings had dead or dying shoots by the end of the experiment (compared to 77-80% in coir substrates) and although all but one of the roots developed lesions, all were able to recover on their own with CWE. CWE further increased shoot health and also prevented 57% of the roots from developing lesions. In a second study, two different CWE were used to examine the effect on root border cell dispersion and dynamics in pea, maize, cotton, and cucumber and its relation to disease suppression. Dispersal of border cells after immersion of roots into water or CWE was measured by direct observation over time using a compound microscope and stereoscope. Pictures were taken and the number of border cells released into suspension were enumerated by counting the total number of cells in aliquots taken from the suspension. Border cells formed a mass surrounding root tips within seconds after exposure to water, and most cells dispersed into suspension spontaneously. In CWE, >90% of the border cell population instead remained appressed to the root surface, even after vigorous agitation. This altered border cell phenomena was consistent for pea, maize, and cotton and for both CWE tested. For most cucumber roots (n=86/95), inhibition of border cell dispersal in both CWE was similar to that observed in pea, maize, and cotton. However, some individual cucumber roots (8±5%) exhibited a distinct phenotype. For example, border cells of one root immersed into CWE remained tightly adhered to the root tip even after 30 minutes while border cells of another root immersed at the same time in the same sample of CWE expanded significantly within 5 minutes and continued to expand over time. In a previous study, sheath development over time in growth pouches also was distinct in cucumber compared with pea, with detachment of the sheaths over time, and root infection was reduced by only 38% in cucumber compared with 100% protection in pea (Curlango-Rivera et al. 2013). Further research is needed to evaluate whether this difference in retention of border cell sheaths plays a role in the observed difference in inhibition of root infection. In the third study, a series of investigations were conducted to isolate different factors that contribute to the suppression ability of a CWE by changing incrementally changing some aspect of the CWE production process. The basic aerated CWE recipe (with molasses, kelp, humic acid, rock phosphate, and silica) provided 100% protection of pea from root disease while the non-aerated basic recipe CWE provided 72% protection. Aerated CWE made of only compost and water resulted in 58% protection. It was found that molasses did not contribute to the suppression ability of the ACWE, while kelp contributed strongly. When soluble kelp was added by itself to the compost and water, the CWE provided 80% suppression. However, when all additives were included except molasses and kelp, suppression remained high (93%) indicating that humic acids, rock phosphate, and/or silica were also major contributors toward the suppression effect. Optimal fermentation time for ACWE was 24 hr to achieve 100% suppression, with increased time resulting in inconsistent suppression results. Optimal fermentation time for NCWE was 3 days or 8 days. These studies are important contributions to understanding the differences that might be expected in CWE suppression when growing in different substrates, some of the factors in the production of CWE that affects the ability of a CWE to suppress disease, and the phenotypic effect CWE has on the root zone of plants and the possible relationship between that effect and disease suppression.

Biomass and biomass-derived waste are important renewable energy sources which plays a vital role in greenhouse gas reduction from fossil fuel.  Biomass can be degraded in a process known as anaerobic digestion (AD) to produce biogas. Biogas is a mixture of methane and carbon dioxide which is utilized as a renewable source of energy. This project was based on the investigation of AD process in Nordvästra Skånes Renhållnings AB (NSR) a biogas facility in Helsingborg Sweden. A lab simulation of NSR digesters was conducted to evaluate the effects of swine manure on AD using two continuously stirred tank reactors (CSTR) R1 (control) and R2 with a working volume of 4L for 21 weeks. The study was divided into 4 periods and the investigation was carried out by increasing the organic loading rate (OLR) step wise from 2.5 to 3.6 gVSL-1day-1. To assess the effects of swine manure, the performance and stability of the reactors were monitored by collecting data from process parameters. These process parameters included biogas production, pH, volatile fatty acids, methane yield, methane content and organic solids (total and volatile solids). Increase in OLR resulted in increase biogas production in both reactors, however R2 with additional swine manure (15%) produced more biogas than R1. Methane yield was fairly stable during the experiment and had a similar trend in both reactors, but however R2 had a slightly higher average yield (730±60 mLCH4 gVS-1) than R1 (690±60 mLCH4 gVS-1) during the entire experiment. Increase OLR resulted in increase VFA in period 2; R2 with additional swine manure had a lower peak VFA concentration of 25 mM as compared to 33mM in R1.  The characteristics of NSR substrate mix and swine manure provided a good buffering system (stable pH), and reactors were still running stably at 3.6 gVSL-1day-1. Furthermore swine manure was investigated to contain macro-nutrients and trace metals which might have enhanced the AD process in R2 containing more Co, Zn, Ni and Mo than R1. Since this investigation was a simulation, the waste mix used at NSR contained 7% swine manure, this made it difficult to give clearer conclusions about the effects of co-digestion of swine manure on the biogas process since the control (R1) had 7% swine manure. Keywords: Anaerobic digestion, co-digestion, swine manure, substrate mix, organic loading rate, biogas production, methane yield, VFA, process parameters, CSTR.

The type III secretion system (T3SS) of pathogenic Yersinia pseudotuberculosis is involved in virulence. The syringe-like secretion system spans both bacterial membranes and is responsible for the ability of Yersinia to transfer toxic proteins (Yop proteins) into the eukaryotic target cell. The T3SS is believed to have evolved from the flagellum and regulation of the T3SS is a complex event that involves a series of regulatory proteins, whereby two are YscP and YscU. In a regulatory model, called the substrate specificity switch, both proteins act together to ensure proper T3SS structure and function by regulating a stop in YscF needle protein export with a shift to Yop effector secretion. YscU undergoes autoproteolysis at a conserved motif consisting of amino acids Asparagine-Proline-Threonine-Histidine (NPTH). Processing generates a C-terminal 10 kDa peptide, YscUCC. Processing is crucial for proper T3SS regulation and function both in vitro and in vivo. Full-length YscU does not support Yop secretion and after cleavage, YscUCC remains attached to the rest of YscU and acts as a negative block on T3S. Relief of this negative block is suggested to occur through displacement of YscUCC from the rest of YscU. Thorough control of many different cellular processes is brought by the heat shock proteins (HSPs) DnaK and DnaJ. Due to their multiple regulatory functions, mutations in the hsp-genes lead to pleiotropic effects. DnaK and DnaJ are essential for proper flagellum driven motion of bacteria, but more so; they ensure proper Yersinia T3SS function in vivo. Furthermore, DnaJ interacts with YscU and may be directly involved in T3SS regulation. Virulence of Yersinia is regulated on many levels. A previously identified virulence associated protein, VagH, is now characterized as an S-adenosyl-methionine dependent methyltransferase. The targets of the methylation activity of VagH are release factors 1 and 2 (RF1 and RF2), that are important for translation termination. The enzymatic activity of VagH is important for Yop secretion and a vagH mutant up-regulates a T3SS negative regulatory protein, YopD. Furthermore, a vagH mutant is avirulent in a mouse infection model, but is not affected in macrophage intracellular survival. The importance of VagH in vivo makes it a possible target for novel antimicrobial therapy.

No description available.

An ID generating circuit is unquestionably the core of a chipless RFID tag. For convenience of printing process and cost consideration, the circuit should be kept as simple as possible. Based on the cognition, an 8-bit time-domain based ID generating circuit that merely consists of a ML and eight capacitors was offered, and implemented on photo-paper substrates via inkjet printing process. In addition to the experimental measurements, the circuit was also input into circuit simulators for cross-validation. The good agreement between simulations and measurements is observed, exhibiting the tag technical feasibility. Besides of low cost, the tag has wide compatibility with current licensed RFID spectrum, which will facilitate the future deployment in real applications. Compared   to  time-domain   based  chipless   tags,  frequency   signatures   based chipless RFID tags are expected to offer a larger coding capacity. As a response, we presented a 10-bit frequency-domain based chipless RFID tag. The tag composed of ten configurable LC resonators was implemented on flexible polyimide substrate by using  fast  toner-transferring  process.  Field  measurements  revealed  not  only  the practicability  of  the  tag,  but  also  the  high  signal  to  noise  ratio  (SNR).  Another frequency domain tag consists of a configurable coplanar LC resonator. With the use of all printing process, the tag was for the first time realized on common packaging papers.  The tag feasibility was confirmed by subsequent measurements. Owing to the ultra-low cost potential and large SNR, The tag may find wide applications in typical RFID solutions such as management of paper tickets for social events and governing of smart documents. Ultra wide band (UWB) technology possesses a number of inherent merits such as high speed communication and large capacity, multi-path immunity, accurate ranging and positioning, penetration through obstacles, as well as extremely low-cost and low- power transmitters. Thus, passive UWB RFIDs are expected to play an important pole in  the future identification applications for IoT. We explained the feature difference between  UWB  chipless  tags  and  chip  based  tags,  and  forecasted  the  applications respectively  based on the comparison  between the two technologies.  It is expected that the two technologies will coexist and compensate each other in the applications of IoT. Lastly, the thesis ends up with brief summary of the author’s contributions, and technical prospect for the future development of printable chipless RFID tags. / <p>QC 20140304</p>

Activation of the Unfolded Protein Response (UPR) following stress in the Endoplasmic Reticulum (ER) is an important mechanism by which obesity results in insulin resistance and type II diabetes. We uncovered a role for the adaptor protein Nck in modulating the UPR. In this study, we report that obese Nck1-/- mice, which show lower levels of UPR in liver and adipose tissue, present improved insulin signalling in these tissues. We established that the effect of Nck1 is cell autonomous by showing that HepG2 cells treated with Nck1 siRNA have reduced ER stress-induced UPR and Insulin Receptor Substrate-1 (IRS-1) serine phosphorylation. In these cells, we observed that the IRS-1 levels and activation of signalling components downstream of the insulin receptor were increased. This correlates with enhanced cell survival to stress and insulin stimulated glycogen synthesis. Overall, we demonstrated that Nck1 participates in ER-stress-induced insulin resistance and regulation of IRS-1-dependent signalling.

No description available.