No description available.

Recently, point-of-care diagnostics has gained great attention because it can improve patient’s quality of life. Electrochemical diagnostic systems are promising because of their miniaturizability and low-cost. However, fabrication of such devices requires special skills as well as expensive equipment and supplies. This thesis is based on a research project aimed at fabricating electrochemical sensors combing wax printing and inkjet printing or wax printing and hand painting. The electrochemical sensors can be used for measuring different kinds of electrochemical analytes like dopamine, uric acid by electrochemical methods like amperometry, which can show great calibration curve. The LOD of dopamine, uric acid, ascorbic acid, Nile Blue, hydrogen peroxide and ferrocene is 0.015 µM, 7.3 µM, 30 µM, 1.3 µM, 8 nM and 30 µM, respectively. Further, we can modify the electrochemical sensor by using multiwall carbon nanotube in order to improve the sensitivity of the electrochemical sensors. This modified electrochemical sensor can also be used as immunoassay by sandwich format ELISA for detecting carcinoembryonic antigen (CEA), which has been designated as a reliable biomarker for several types of cancers. We found that the CNT modified hand-painting device can detect CEA down to 0.6 ng/mL, which is three times lower than the cut-off value of diagnosis, i.e. 5 ng/mL in blood.

Controlled Environment Agriculture (CEA) is an expanding industry in the United States. Lettuce (Lactuca sativa) possesses considerable economic importance as one of the foremost leafy vegetables worldwide in terms of financial value for production in CEA. Rapid growth rate, high yield, and potential return further enhance its suitability for cultivation within CEA. Pursuing optimal and sustainable nutrient concentrations for crops in CEA is a continuous requirement for an expanding industry. This study is set to investigate the impact of different potassium (K) sources and concentrations on 'Green Oakleaf' lettuce growth. The K concentration within the Virginia Tech base hydroponic lettuce fertilizer was increased,1x, 2x, and 3x the normal rates of K ppm, through the addition of potassium chloride (KCl) or potassium sulfate (K2SO4). To account for rising electrical conductivity (EC), due to the increase of K, KCl treatments were recreated with standardized EC through the addition of Sodium Chloride (NaCl). The Spatially and Mechanically Accurate Robotic Table (SMART) in an indoor space was utilized to cultivate and image plant growth over time through pixel count. Growth index and chlorophyll content were recorded weekly, while the fresh weight and dry weight of shoots were recorded at harvest. The KCl treatment with the highest concentration,4x K ppm, as well as those with standardized EC, led to reduced yield when compared to other treatments. All K2SO4 treatments showed no difference in growth when compared to the base solution. K source and concentration, as well as fertilizer EC, were all identified as factors influencing the impact of fertilizers on the optimization of lettuce yield. / Master of Science in Life Sciences / Controlled Environment Agriculture (CEA) is a growing industry in the U.S., and lettuce is one of the most important leafy vegetables globally in terms of economic value. As the industry expands, finding the best and most sustainable nutrient levels for crops is essential. This study explored how different types and amounts of potassium (K) in fertilizers affect the growth of 'Green Oakleaf' lettuce. Potassium levels in the base fertilizer were increased to 1x, 2x, and 3x the normal amount using either potassium chloride (KCl) or potassium sulfate (K₂SO₄). The study measured various growth factors like chlorophyll content, plant weight, and plant image pixel counts. It found that higher levels of potassium chloride (KCl) negatively impacted plant growth, while potassium sulfate (K₂SO₄) did not have the same effect. The research also showed that adding sodium chloride (NaCl) increased the salt content, measured by electrical conductivity (EC), in the fertilizer, which reduced lettuce growth. The findings suggest that high fertilizer ECs, not potassium itself, were the main cause of poor plant growth. Overall, the study identified potassium source and concentration, as well as fertilizer EC levels, as important factors in optimizing fertilizer for lettuce growth.

Stress is one of the leading predisposing factors for the onset of anxiety and depression. The mechanisms underlying stress vulnerability remain not fully understood and this gap significantly delays the advancement of the biomedical field. Pituitary adenylate cyclase-activating polypeptide (PACAP), a 38-amino acid peptide, has been proposed to regulate the stress response by acting at multiple levels. The central hypothesis of this work was that the PACAP system of the extended amygdala, a basal forebrain structure that includes the central nucleus of the amygdala (CeA) and the bed nucleus of the stria terminalis (BNST), plays a critical role in the physiological and pathological behavioral response to stress. I found that central (intracerebroventricular) administration of PACAP in rats is able to produce a depressive-like endophenotype, as measured by increased current threshold for intracranial self-stimulation (ICSS), reduced preference for a sweet solution, and reduced time spent interacting with a novel animal in a social interaction test. I then went on investigating the brain structures and mechanisms contributing to PACAP-induced behavioral effects. I found that microinfusion of PACAP, but not VIP, into the CeA and BNST caused a dose-dependent increase in acoustic startle response (ASR), a rapid defensive reflex that is an index of stress. In addition, PACAP(6-38) infusions into either of these structures was instead able to prevent the sensitization of ASR induced by footshock stress, in line with the observation that the acute exposure to footshock stress induced a significant increase in PACAP, but not VIP, levels in both the CeA and the BNST. Finally, I found that the continuous recruitment of the PACAP system of the CeA was essential to the emergence of the negative outcomes of chronic stress. Indeed, chronic social defeat stress significantly increased PACAP levels in the CeA, but not the BNST; furthermore, viral vector-mediated knockdown of the PACAP receptor PAC1R in the CeA significantly attenuated decreased body weight gain, decreased saccharin consumption, and heightened anxiety-like behavior induced by chronic social defeat and also prevented the increase in CeA corticotropin-releasing factor (CRF) levels. The results obtained provide novel insights into the neurobiological mechanisms underlying the psychopathological consequences of stress. / 2020-06-12T00:00:00Z

After many years of research have been developed, and then in January 2013 approved by the European Medicines Agency new multicomponent vaccine against meningococcal disease Group B Bexsero from Novartis. Meningococcal disease, because of its rapid progression and tragic consequences, a very dangerous disease. The aim of my thesis was to try to quantify the impact on the costs and benefits of the introduction of vaccination for the most vulnerable groups, namely children after birth to 4 years of age, by comparing the hypothetical vaccinated and unvaccinated cohorts. The work itself has not demonstrated at today's prices and epidemiological data Bexsero vaccines, cost efficiency. However, at a reduced cost or increased incidence of cases appear to vaccination Bexsero as well utilized resources.

Siglecs and CEA are two families of cell surface proteins belonging to the immunoglobulin superfamily. They are thought to be involved in cell-cell interactions and have various other biological functions. We used the GENECONV program that applies statistical tests to detect gene conversion events in each family of five primate species. For the Siglec family, we found that gene conversions are frequent between CD33rSiglec genes, but are absent between their conserved Siglec genes. For the CEA family, half of gene conversion events detected are located in coding regions. A significant positive correlation was found between the length of the conversions and the similarity of the converted regions only in the Siglec gene family. Moreover, we found an increase in GC-content and similarity in converted regions compared to non-converted regions of the two families. Furthermore, in the two families, gene conversions occur more frequently in the extracellular domains of proteins, and rarely in their transmembrane and cytoplasmic regions. Finally, these two families appear to be evolving neutrally or under negative selection.

Siglecs and CEA are two families of cell surface proteins belonging to the immunoglobulin superfamily. They are thought to be involved in cell-cell interactions and have various other biological functions. We used the GENECONV program that applies statistical tests to detect gene conversion events in each family of five primate species. For the Siglec family, we found that gene conversions are frequent between CD33rSiglec genes, but are absent between their conserved Siglec genes. For the CEA family, half of gene conversion events detected are located in coding regions. A significant positive correlation was found between the length of the conversions and the similarity of the converted regions only in the Siglec gene family. Moreover, we found an increase in GC-content and similarity in converted regions compared to non-converted regions of the two families. Furthermore, in the two families, gene conversions occur more frequently in the extracellular domains of proteins, and rarely in their transmembrane and cytoplasmic regions. Finally, these two families appear to be evolving neutrally or under negative selection.

No description available.

Siglecs and CEA are two families of cell surface proteins belonging to the immunoglobulin superfamily. They are thought to be involved in cell-cell interactions and have various other biological functions. We used the GENECONV program that applies statistical tests to detect gene conversion events in each family of five primate species. For the Siglec family, we found that gene conversions are frequent between CD33rSiglec genes, but are absent between their conserved Siglec genes. For the CEA family, half of gene conversion events detected are located in coding regions. A significant positive correlation was found between the length of the conversions and the similarity of the converted regions only in the Siglec gene family. Moreover, we found an increase in GC-content and similarity in converted regions compared to non-converted regions of the two families. Furthermore, in the two families, gene conversions occur more frequently in the extracellular domains of proteins, and rarely in their transmembrane and cytoplasmic regions. Finally, these two families appear to be evolving neutrally or under negative selection.

Vertical farming has been proposed as a solution for providing food security for an increasing, urbanized human population. Light-emitting diode (LED) technology has become increasingly affordable and efficient, making it an ideal choice as artificial lighting for indoor farms. Still largely undiscovered parameters are the optimal plant varieties and types of production systems for plant growth, profit, and human nutrition. Aquaponics may be able to provide sustainable animal protein for vertical farms, increasing their ability to provide more substantial nutrition to consumers. This research aimed to better understand vertical farming as a food production system, and to determine if aquaponics can be an appropriate and applicable fit for it. The experiment was a randomized, factorial design with three independent variables: (1) LED photoperiod interval (2) LED-plant distance, and (3) nutrient solution, as well as several dependent variables to assess both plant yield and quality. A 4-tiered shelving unit was constructed for nutrient film technique (NFT) plant production, and treatments were assigned to each row: (1) LED experiment: Row A, 12/12hr reduced photoperiod with adjustable LEDs 4in. above plant surface; Row B, 2/1hr altered photoperiod interval relative to the control; Row C (control), 16/8hr “standard” photoperiod. (2) Nutrient experiment: Row C, aquaponic nutrient solution; Row H, hydroponic nutrient solution. Rows C and H had matched photoperiod and light intensity. Kale from Row A had significantly lower fresh and dry plant yield relative to the control, Row C (p<0.05). Hydroponic romaine, Row H, had significantly higher plant yield relative to aquaponics, Row C (p<0.05). Butterhead yields were not significantly different in any treatments (p>0.05). Future research may implement a larger sample size of only one plant variety, harvest plants earlier, limit light intensity variation, effectively “balance” the aquaponics system, and have more measures of plant “quality.”