Physiological and genetic characterization of sorghum exposed to early season chilling and terminal heat and drought stress

Doctor of PhilosophyDepartment of AgronomyS.V. Krishna JagadishSorghum (Sorghum bicolor (L.) Moench) is one of the hardiest crop to abiotic stresses compared with other grain crops. However early stage chilling, terminal heat and drought stress are three most damaging abiotic stresses that have limited sorghum productivity in the US Great plains and other locations having similar environmental conditions. Three studies were conducted with an overall goal aimed at increasing grain sorghum’s resilience to harsh climatic conditions. In the first study, four promising chilling stress tolerant sorghum advanced breeding lines, a known early stage chilling tolerant Chinese landrace (Shan Qui Red - SQR) and a susceptible US elite cultivar (RTx430) as checks were assessed for chilling tolerance during emergence and early growth under field and controlled environments. Aerial phenotyping using unmanned aircraft systems (UAS) fitted with multispectral camera was used to capture reflectance-based vegetation indices (NDVI and NDRE) in field experiments. Some advanced breeding lines with superior agronomic background also recorded significantly better emergence, seedling growth and vigor compared to SQR under chilling conditions. Aerial phenotyping indices from images taken between 30 and 60 days after emergence were consistently correlated with destructive measurements under early plantings, indicating their effectiveness in differentiating chilling responses. Second study was conducted to understand physiological mechanisms inducing heat stress resilience in sorghum during flowering. A diverse set of sorghum inbreds and selected hybrids were tested under greenhouse, growth chamber facilities and field conditions. A highly conserved early-morning-flowering mechanism was observed across all the inbreds and hybrids, with the peak anthesis wherein >90% of florets completed flowering within 30 min after dawn. The conserved response was consistent even under drought stress and heat stress exposure imposed at different times of the day. Our findings report a novel heat escaping early-morning-flowering mechanism effectively employed by sorghum to minimize heat stress impact at anthesis. Another experiment with sequential increase in daytime temperature treatments suggest heat stress induced loss in pollen viability to be a key factor resulting in reduced seed-set and grain yield. The findings suggest heat stress could have a greater impact on post-pollen germination processes such as fertilization, embryo formation and development. We identified a heat tolerant genotype “Macia” which appears to be a promising donor for developing improved heat tolerant sorghum hybrids. In the third study, a bi-parental recombinant inbred lines (RILs) mapping population developed from elite post flowering drought susceptible cultivar (RTx430) and a known drought tolerant cultivar (SC35) were evaluated under wide spectrum of environments and moisture conditions. Several novel and major QTL for grain yield, panicle neck diameter, effective quantum yield of photosystem II and chlorophyll content were identified. The genomic regions and the candidate genes within these regions can potentially help in improving source and sink dynamics in sorghum under diverse environments. The findings from these studies will complement ongoing efforts in developing future sorghum with enhanced resilience to different abiotic stresses that continue to limit sorghum productivity

Ultrasensitive Immunosensing Platform Based on Analyte Induced Disruption of Luminescence Quenching (AIDLuQ)

In this study, we design an extremely fast and sensitive immunosensing platform using graphene as the sensing platform. A solution containing a mixture of graphene nanoplatelets and gold nanoparticles was coated on to a copier paper using a spray gun to form a uniform coating. Fluorescent quantum dots (QDs) functionalized with antibodies (Ab) were drop casted on to this platform, whose fluorescence was quenched by the graphene on the graphene/gold paper. With the addition of the antigen to this graphene/gold-QD-Ab complex, a disruption of quenching was observed, and the fluorescence intensity increased with increasing concentration of the antigen. A detection limit of as low as 10 fM was obtained for the detection of human Immunoglobulin G (IgG)

Isotope-reinforced polyunsaturated fatty acids improve Parkinson’s disease-like phenotype in rats overexpressing α-synuclein

Producción CientíficaLipid peroxidation is a key to a portfolio of neurodegenerative diseases and plays a central role in α-synuclein (α-syn) toxicity, mitochondrial dysfunction and neuronal death, all key processes in the pathogenesis of Parkinson's disease (PD). Polyunsaturated fatty acids (PUFAs) are important constituents of the synaptic and mitochondrial membranes and are often the first molecular targets attacked by reactive oxygen species (ROS). The rate-limiting step of the chain reaction of ROS-initiated PUFAs autoxidation involves hydrogen abstraction at bis-allylic sites, which can be slowed down if hydrogens are replaced with deuteriums. In this study, we show that targeted overexpression of human A53T α-syn using an AAV vector unilaterally in the rat substantia nigra reproduces some of pathological features seen in PD patients. Chronic dietary supplementation with deuterated PUFAs (D-PUFAs), specifically 0.8% D-linoleic and 0.3% H-linolenic, produced significant disease-modifying beneficial effects against α-syn-induced motor deficits, synaptic pathology, oxidative damage, mitochondrial dysfunction, disrupted trafficking along axons, inflammation and DA neuronal loss. These findings support the clinical evaluation of D-PUFAs as a neuroprotective therapy for PD

Late-Season Nitrogen Applications Increase Soybean Yield and Seed Protein Concentration

Low seed and meal protein concentration in modern high-yielding soybean [Glycine max L. (Merr.)] cultivars is a major concern but there is limited information on effective cultural practices to address this issue. In the objective of dealing with this problem, this study conducted field experiments in 2019 and 2020 to evaluate the response of seed and meal protein concentrations to the interactive effects of late-season inputs [control, a liquid Bradyrhizobium japonicum inoculation at R3, and 202 kg ha−1 nitrogen (N) fertilizer applied after R5], previous cover crop (fallow or cereal cover crop with residue removed), and short- and full-season maturity group cultivars at three U.S. locations (Fayetteville, Arkansas; Lexington, Kentucky; and St. Paul, Minnesota). The results showed that cover crops had a negative effect on yield in two out of six site-years and decreased seed protein concentration by 8.2 mg g−1 on average in Minnesota. Inoculant applications at R3 did not affect seed protein concentration or yield. The applications of N fertilizer after R5 increased seed protein concentration by 6 to 15 mg g−1, and increased yield in Arkansas by 13% and in Minnesota by 11% relative to the unfertilized control. This study showed that late-season N applications can be an effective cultural practice to increase soybean meal protein concentration in modern high-yielding cultivars above the minimum threshold required by the industry. New research is necessary to investigate sustainable management practices that increase N availability to soybeans late in the season

Customer Service Analysis : Case: Sky Club Department of Yeti Airlines, Nepal

In recent year, competition in business field is significantly growing and an organization cannot focus only on price but also they have to focus on customer service and satisfaction level. The objective of this thesis is to find out the level of customer service experience and satisfaction and provide suggestions for the future development. Customer service and customer satisfaction are relates to each other. Therefore, good customer service can get high level of customer satisfaction. A high level of customer satisfaction ensures the benefits of the company. It can assist the company to assure that what kind of customers are getting and what their needs are. So that a company can made their service package according to their customers and their needs. The theoretical perspectives, this thesis includes definition of customer satisfaction, customer service and service quality. Theory composed to create a good customer satisfaction through customer service and service quality. The analysis of the study is accomplished to measure the customer satisfaction level and customer service by research data. The study of survey results showed that the satisfaction level of customer service of Sky Club of Yeti Airlines is in a good position. Customers suggest that company should maintain the quality of internet service in a better way. According to the questionnaire, attitude of employees seems in a good position. This study ends with some suggestions about the online ticketing system, focus on retaining and satisfying the present members from switching to other airlines by providing better services

Patent Information, Freedom to Operate and “Global Access”: A Case Study of Dengue Vaccines Under Development

This Global Challenges Report1 presents a “global access” freedom to operate (FTO) analysis2 of six vaccines under development against dengue hemorrhagic fever (hereinafter referred to as “dengue”), a Neglected Tropical Disease (NTD)3 endemic to tropical regions. Developing a vaccine against dengue is challenging because there are four closely related viruses that can cause the disease. Several vaccines are in various stages of development, including by developing country institutions from both the public and private sector. Clinical trials are underway on five candidate vaccines with encouraging results. After an extended executive summary (Section 1) and an introduction and description of the methodology (Section 2), the report reviews the scientific basis of the various vaccines under development (Section 3). A successful vaccine should immunize against all four types, and substantial progress towards the development of such a vaccine has been made in the last decade. The range of vaccines under development include live attenuated vaccines, live chimeric virus vaccines and live recombinant, DNA and subunit vaccines. Each type comes with its own unique challenges and benefits, though live attenuated vaccines have been the most successful to date4. Section 4 presents the patent situation relating to six of the dengue vaccines under development. Some 10,800 patents and patent applications were found to have “dengue” in the abstract, title, text or claims, corresponding to 4,500 patent families. Of these, 700 families were found to be outside the scope. Of the remaining 3,800 patent families, 55 patents or patent families were deemed pertinent to the six vaccines discussed in this report. The number of patent families related to a given vaccine ranged from five to 22. Most of these were filed in developed countries with only a small number also filed in select developing countries. Each of the patent groups occupied a well-defined space in the patent landscape, with little overlap in the specific technological field. This finding has important implications for IP management strategies in that few, if any, cross-licensing deals may be required to bring any given vaccine to market. This aspect is further discussed in Section 5 on the licensing status of the vaccines under development. The results of this “global access” FTO suggest that there are few major constraints related to patents that could complicate developing-country access to the vaccines under development. It should be noted that the analysis is limited to patent data and licensing information. Market considerations such as economies of scale, pricing and regulatory approval, or efficacy of the vaccine itself, are beyond its scope. Notwithstanding the relatively few patents applied for or issued in developing countries, an effective transfer of productive capacity of any of the vaccines to developing countries would require consideration of additional elements beyond patent data. Those include regulatory requirements, issues relating to know-how, and possible access to materials, such as cell lines. The report, nevertheless, identifies the state of product development, identifies key players, and the patent and licensing status, which together facilitate the development of effective strategies, including collaborations, as appropriate. These should enable early product deployment in areas where dengue most affects people’s lives and thus lead to accelerated access to dengue vaccines by those most in need. This report provides an informal guide for those wishing to better understand the important interplay of intellectual property (IP) with product development, manufacture and delivery (viz. access). It can be seen as an example of using patent information to address major global challenges, including access to medicines, and thus contribute to informed policy discussions, strategic research planning and technology transfer, and in that way, benefit humanity