Construction of genetic linkage map and QTL analysis of sinksize traits in pearl millet (Pennisetum glaucum)

A linkage map, primarily based on SSCP-SNP markers, was constructed using 188 F2:3 (F2-derived F3) mapping population progenies derived from a cross between two pearl millet inbred lines having diverse pedigrees. The parents had large differences for two sink size traits (grain size and panicle diameter), and also differed for panicle length. The skeleton linkage map covered 1019 cM and it comprised of 44 loci (detected with 24 SSCP-SNP, 10 genomic SSR, 6 EST-SSR and 4 STS primer pairs) distributed across the seven linkage groups. Average adjacent-marker intervals ranged from 14 cM on LG1 to 38 cM on LG6, with an overall mean of 23 cM. Using the F2 linkage map and phenotypic data collected from the F2 and F2:3 generations of the mapping population, a total of 18 putative QTLs were detected for the three sink-size components. Eight QTLs explained 42.7% of observed phenotypic variation for panicle length, with individual QTLs explaining 6.1 to 18.2% using the F2:3 data set. For panicle diameter, 5 QTLs explained 45.8% of observed phenotypic variation with individual QTLs accounting for 6.3 to 30.2%. Similarly for grain size, 5 QTLs explained 29.6% of phenotypic variation with individual QTLs accounting for 6.1 to 8.9%. Genomic regions associated with panicle length, panicle diameter and grain size co-mapped on LG6 between Xpsms88 and Xpsms2270, indicating the existence of a gene or gene cluster with major effects involved in the control of significant proportions of the phenotypic variation for all three sink-size traits. The QTLs for panicle length on LG2 and LG6 (LOD>3 in both F2 and F2:3 data sets), for panicle diameter on LG2 and LG3 (LOD>14 in the F2:3 data set) and for grain size on LG3 and LG6 (LOD>3 in both F2 and F2:3 data sets) were identified as promising candidates for validation prior to possible application in marker-assisted breeding

Targeted Anti-Angiogenic Therapy in Metastatic Renal Cell Carcinoma and Methodological Improvements in Assessment of Therapeutic Response with Imaging Biomarkers

Background: Drugs targeting angiogenic pathway remain the mainstay of treatment for metastatic renal cell carcinoma (mRCC). Tyrosine Kinase Inhibitors (TKI) as Sunitinib, Pazopanib as single agents and humanised monoclonal antibody bevacizumab (Bev) in combination with Interferon- α2a (IFN) have established as the first-line therapy for mRCC. Despite improvements in treatment, there are multiple questions which remain unanswered. In the combination of Bev and IFN, the respective role of each drug and whether any additional anti-angiogenic activity is gained by adding IFN to Bev remains unknown. As the clinical benefit obtained with these cytostatic agents does not always correlate with the conventional response assessment techniques as RECIST, it is necessary to reconsider the methods by which we assess benefit from these therapies. In this thesis, I report three studies aiming to answer these questions. Methods: With the clinical trial reported here, I explore whether Bev induced changes in vascular parameters measured by Dynamic Contrast Enhanced MRI (DCE-MRI) is significantly enhanced by the addition of IFN. In a phase II, randomised, open labelled, multicentre trial, treatment naïve mRCC patients were randomised to receive Bev on its own or in combination with a low dose (3MU) or standard dose (9MU) IFN. DCE-MRI was used to assess the changes in vascularity with the primary endpoint being, changes in transfer coefficient (Ktrans) after six weeks of treatment. I also report two retrospective imaging-based studies, using contrast-enhanced CT scans, performed to improve the methodology of response assessment for these antiangiogenic therapeutics. Here I explore the use of a) combining changes in size and arterial phase contrast enhancement measured using CT scan and b) changes in CT texture as methods of therapeutic response assessment in mRCC patients treated with TKI. Results: With the phase 2 clinical trial, we faced significant difficulty in recruitment as a result of restrictions in access to treatment in NHS, other competing studies and restrictions proposed by the DCE-MRI inclusion criteria. With slow recruitment, an unplanned analysis was performed after 21 patients were recruited. Analysis of primary endpoint showed no trend in the difference between arms with no correlation found between change in Ktrans and addition of IFN to bevacizumab. Effect size analysis performed due to the small numbers recruited failed to show any significance in the observed difference in Ktrans. Change in Ktrans and Kep may identify a group of patients likely to have PFS > 6 months, but this observation needs to evaluation in a larger sample size. Measuring size and change in arterial phase enhancement retrospectively using CT, a new criterion "modified" Choi, which prerequisite a combination of a decrease in arterial phase density by 15% and a decrease in size by 10% for response was proposed. Response assessment was measured with RECIST, Choi and modified Choi individually in 20 evaluable patients retrospectively and clinical benefit compared with Kaplan-Meier statistics and Log-Rank test. Response assessment as defined by the modified Choi criteria successfully identified patients who received clinical benefit from the treatment. Time to progression (TTP) was 448 days for the partial response and 89 days for stable disease as per the new criteria which were statistically significant with a p-value of 0.002. The second retrospective analysis explored the textural changes in enhanced CT scan. Performed in collaboration with researchers from Brighton University who developed the software algorithm used to assess changes in entropy and uniformity, 87 metastases from 39 patients with mRCC were analysed at baseline and after two cycles of TKI treatment. Textural parameters and response assessment criteria were correlated with TTP. After two cycles of TKI, the decrease in tumour entropy was 3%-45%, and increase in uniformity was 5%-21%. At a threshold change of -2% with uniformity, on a coarse scale of 2.5, the textural change was able to separate responders from non-responders. With Kaplan-Meier analysis comparing all four criteria, the percentage change in uniformity was statistically more significant than for RECIST, Choi, and Modified Choi criteria. Cox regression analysis showed that texture uniformity was an independent predictor of time to progression. Discussion: With the studies reported here, I was able to demonstrate the importance of improving the methodology in assessment of therapeutic response to targeted anti-angiogenic therapy in metastatic renal cell carcinoma. Even though the clinical trial, terminated early due to slow recruitment, did not reach its primary endpoint, changes in other vascular parameters as Kep combined with changes Ktrans showed tendency towards identifying a group of patients who derived clinical benefit of >6months with these therapies. This is particularly exciting as given the vascular stabilisation effect proposed for bevacizumab, the effusion parameter Kep may be a better tool in assessing response rather than Ktrans and warrants further assessment in a larger cohort. Modified choi criterion and textural analysis are two important methodological improvements in response assessment of cytostatic anti-angiogenic therapy. In the analyses reported here, both techniques have shown superiority over RECIST in response assessment and differentiating mRCC patients who is likely to gain clinical benefit by TKI therapy. Validation of these criteria on a larger patient cohort is important. As these criterions are assessed on standard enhanced CT scans, incorporating these criteria, especially modified choi criterion, as part of standard CT assessment could be performed and will provide a real world validation. Retrospective assessment using larger cohort of patients from previous phase 3 trials or inclusion of these parameters prospectively in phase 3 trials would also help us in evaluating these modalities further

Heteroatom-Doped Graphene-Based Hybrid Materials for Hydrogen Energy Conversion

Energy is becoming a big issue in the present world due to the depletion of current fossil fuels and also due to environmental problems such as global warming and rising pollution levels. Hence, highly efficient and renewable energy materials are required to produce clean electricity. The utilization of different energy sources such as solar energy and wind energy is hampered by their fluctuation in time and non-uniform geographical distribution which are still under nascent stage. In this regard, hydrogen-based renewable energy is very promising due to higher chemical energy per mass of hydrogen (142 MJ kg−1) as compared to liquid hydrocarbons (47 MJ kg−1), zero emission, and its large abundancy on earth. Therefore, electrochemical conversion of hydrogen to electric energy using fuel cells would be the key technology in future. In hydrogen fuel cells, the development of highly efficient electrocatalysts mainly for sluggish cathodic oxygen reduction reaction, with inexpensive and easily available materials, is a major issue. Recent investigations suggest that chemically modified graphene support materials such as nitrogen-doped graphene can generate strong, beneficial catalyst support interactions which considerably enhance the catalyst activity and stability in fuel cells. This chapter describes the fundamental aspects of electrochemical conversion of hydrogen to electric energy using fuel cells. The chapter further explains the role of nitrogen-doped graphene nanomaterials and their hybrids with transition metal and their alloy nanoparticles in fuel cell catalysis

A boundary element method for the strongly nonlinear analysis of surface-piercing hydrofoils

A two-dimensional BEM based scheme is presented for the numerical modeling of the ventilated flow past a surfacepiercing hydrofoil. Fully nonlinear boundary conditions are applied on the free-surface allowing for the modeling of the jets generated as a result of the passage of the hydrofoil through the air-water interface. The scheme is validated through a comparison with self-similar solutions in the case of nonventilating entry and with experiments in the case of ventilating entry. Results are presented for fully wetted and ventilating cases with and without the effects of gravity. Preliminary results are presented for the case of a hydrofoil in rotational motion, simulating the ventilation characteristics of a typical surface-piercing propeller. The fully nonlinear scheme is a step towards quantifying the errors associated with some of the linearizing assumptions made in a 3-D boundary-element tool (PROPCAV) for the modeling of surface-piercing propellers..http://deepblue.lib.umich.edu/bitstream/2027.42/84281/1/CAV2009-final97.pd

Montmorillonite modified by CNx supported Pt for methanol oxidation

A composite support based on nature clay, i.e. montmorillonite (MMT), shows great promise as support materials for Pt electrocatalyst for the methanol oxidation reaction in fuel cell anodes. The reported composite support (CNx-MMT) was prepared via carbonizing MMT which was covered by N-contented polymer. X-ray diffraction and transmission electron microscopy results showed that Pt nanoparticles can be well-dispersed on the composite support with highly dispersed tiny crystal Pt nanoparticles. Cyclic voltammetry measurements showed that the Pt/CNx-MMT has the enhanced electrocatalytic activity in methanol oxidation reaction. The developed Pt catalyst supported on new composite support is catalytically more active for methanol electrooxidation than Pt supported on the conventional carbon support and shows good stability, offering promising potential for application of MMT as support for fuel cell electrocatalysis.Web of Scienc

Enhanced adsorption capacity and selectivity towards strontium ions in aqueous systems by sulfonation of CO2 derived porous carbon

Oxygen-enriched carbon materials derived from carbon dioxide were functionalized using sulfonic acid to remove Sr2+ ions from aqueous solutions. Synthesized sulfonated porous carbon materials (PC-SO3H) showed higher adsorption capacity and selectivity towards Sr2+ than non-functionalized porous carbons (PC). The formation of the C-SO3H functional group in PC-SO3H and its ability to proton exchange with Sr2+ was the main contributor to the enhanced performance. The maximum uptake capacity of Sr2+ by PC-SO3H was 18.97 mg g−1, which was 1.74 times greater than PC. PC-SO3H removed 99.9% and 97.6% of Sr2+ from aqueous solutions with initial Sr2+ concentrations of 5 mg L−1 and 10 mg L−1, respectively. Sr2+ adsorption showed rapid kinetics, reaching the adsorption equilibrium within 1 h with high adsorption capacity at equilibrium which is 3.52 times greater than that of PC. Additionally, PC-SO3H selectively adsorbed Sr2+ even in the presence of excess amounts of competing ions. Sulfonation of oxygen-enriched carbon had a significant effect on enhancing the affinity towards Sr2+ and suppressing adsorption towards other competing ions

Genetic Architecture of Spotted Stem Borer Resistance in Sorghum As Inferred From Qtl Mapping and Synteny with the Maize Genome

The present investigation was carried out to characterize the genetic architecture of spotted stem borer resistance and related agronomic and morphological traits in sorghum. The experimental material for this study consisted of 266 RILs derived from a cross between susceptible parent ICSV 745 and resistant parent PB 15520. These RILs were evaluated for phenotypic traits during the 2007 and 2008 rainy seasons under artificial infestation of stem borer, and were genotyped with 90 polymorphic SSR markers for linkage map construction and QTL analysis. The RILs exhibited wide variation for the observed traits across both of the screening environments. The mean performance of RILs for most of the spotted stem borer resistance except stem tunneling, neared the mid-parental value. Among the observed agronomic and morphological traits, except for testa (presence vs absence) and agronomic performance score, the means of RIL population were skewed towards that of one of the parents. High G×E interaction effects was observed in the RIL population progenies for all the resistance component, agronomic and morphological traits except plant color score and seedling basal pigmentation score, which are largely controlled by single major genes. Across-environment, heritability estimates for the resistance component traits were low to moderate, while for most of the agronomic and morphological traits they were high. From the frequency distributions polygenic inheritance was inferred for most of the observed spotted stem borer resistance and agronomic traits. Presence of transgressive segregation for all the observed resistance component traits except recovery resistance score and all observed agronomic traits — seedling vigor, plant height, time to 50% flowering and number of nodes suggesting that favorable and unfavorable alleles for these traits are dispersed between the two RIL parental lines. A significant and positive association was observed among all the observed resistance component traits, except stem tunneling. Significant association was also observed between various agronomic and morphological traits with resistance component traits such as plant height with stem tunneling, deadheart incidence with time to 50% flowering, plant color with leaf damage score and overall resistance score and recovery resistance score with both plant height and number of nodes

Social Justice Club - Miracle Makers

As members of the Social Justice Service Club our mission is to support the Social Justice LLC and to advance the mission the cause literacy throughout the Greater Miami Valley Region. To that end, we are also charged with fulfilling a voluntary service learning committment for our organization. This year in order to fulfill our obligation, we worked with the Miracle Makers After School Program at at the Ruskin Elementary School. As a service club co-hort, we were able to complete 150 hours of community service in the fall semester by mentoring the students, helping them with their homework, and engaging them in group and one-on-one recreational games. Our presentation will focus on our work and how it reinforces our committment to the Marianist ideals of lead, learn, and serve.https://ecommons.udayton.edu/stander_posters/1260/thumbnail.jp

Synthesis of titanium decorated graphene for renewable energy applications

Reduced graphene oxide (RGO) was prepared from natural graphite by Hummers method. Few layers graphene was decorated with titanium by an incipient wetness impregnation method. The pristine graphene shows hydrogen storage capacity equal to 1.3 wt % while graphene decorated by titanium (RGO-Ti) enhanced hydrogen storage capacity to 1.4 wt%. We showed that titanium addition improved hydrogen storage capacity by chemical interactions. These interactions can be used for fabrication of different graphene-based materials as potential candidates for developing new absorbents for energy application