Optimised germination protocol for jackfruit seeds and evaluation of methods for extraction of DNA suitable for genetic analysis

Jackfruit (Artocarpus heterophyllus) is an underutilised plant that is promising in curbing food and nutritional security in sub-Saharan Africa. However, high level of secondary metabolites in its tissues significantly hampers its genetic characterisation for breeding purposes. Primarily, the compounds react with DNA during the extraction process, thus reducing its yield and quality. The utilisation of leaves from jackfruit seedlings is a potentially effective approach of addressing the challenge, however, limited information is available on efficient jackfruit seed germination procedures. Elucidating effective methods of jackfruit seed germination, and optimising protocols for DNA extraction is crucial in promoting its genetic characterisation studies for identification of superior varieties for propagation. The objective of this study was to evaluate methods of jackfruit seed germination, and DNA extraction procedures using jackfruit leaves. Pre-treatment of seeds with 3% hydrogen peroxide was effective in enhancing seed germination within a short time, compared to distilled water and 3% hydrochloric acid. We optimised a DNA extraction technique by combining CTAB-SDS based approach with an enhanced solvent extraction method. The technique yielded high quantity and quality of DNA from jackfruit leaves, which was appropriate for downstream polymerase chain reaction analysis. The sequence-related amplified polymorphism (SRAP) and simple sequence repeat (SSR) amplifications confirmed the effectiveness of the optimised CTAB-SDS based protocol for extraction of high quality DNA. &nbsp

Non-Equilibrium Statistical Physics of Currents in Queuing Networks

We consider a stable open queuing network as a steady non-equilibrium system of interacting particles. The network is completely specified by its underlying graphical structure, type of interaction at each node, and the Markovian transition rates between nodes. For such systems, we ask the question ``What is the most likely way for large currents to accumulate over time in a network ?'', where time is large compared to the system correlation time scale. We identify two interesting regimes. In the first regime, in which the accumulation of currents over time exceeds the expected value by a small to moderate amount (moderate large deviation), we find that the large-deviation distribution of currents is universal (independent of the interaction details), and there is no long-time and averaged over time accumulation of particles (condensation) at any nodes. In the second regime, in which the accumulation of currents over time exceeds the expected value by a large amount (severe large deviation), we find that the large-deviation current distribution is sensitive to interaction details, and there is a long-time accumulation of particles (condensation) at some nodes. The transition between the two regimes can be described as a dynamical second order phase transition. We illustrate these ideas using the simple, yet non-trivial, example of a single node with feedback.Comment: 26 pages, 5 figure

Fundamentals of mold growth in indoor environments and strategies for healthy living

Today, indoor mold and moisture, and their associated health effects, are a society-wide problem. The economic consequences of indoor mold and moisture are enormous. Their global dimension has been emphasized in several recent international publications, stressing that the most important means for avoiding adverse health effects is the prevention (or minimization) of persistent dampness and microbial growth on interior surfaces and in building structures. This book aims to describe the fundamentals of indoor mold growth as a prerequisite to tackle mold growth in the existing building stock as well as in future energy efficient buildings. It brings together different disciplinary points of view on indoor mold, ranging from physics and material science to microbiology and health sciences. The contents have been outlined according to three main issues: Fundamentals, particularly addressing the crucial roles of water and materials, Health, including a state-of-the-art description of the health-related effects of indoor molds, and Strategies, integrating remediation, prevention and policies