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Light is an important environmental factor which affects plant growth, through changes of intensity and quality. In this study, monochromatic white (control), red (660 nm), and blue (430 nm) light-emitting diodes (LEDs) were used to treat tea short cuttings. The results showed the most adventitious roots in blue light treated tea cuttings, but the lowest roots in that treated by red light. In order to explore the molecular mechanism of light quality affecting adventitious root formation, we performed full-length transcriptome and metabolome analyses of mature leaves under three light qualities, and then conducted weighted gene co-expression network analysis (WGCNA). Phytohormone analysis showed that Indole-3-carboxylic acid (ICA), Abscisic acid (ABA), ABA-glucosyl ester (ABA-GE), trans-Zeatin (tZ), and Jasmonic acid (JA) contents in mature leaves under blue light were significantly higher than those under white and red light. A crosstalk regulatory network comprising 23 co-expression modules was successfully constructed. Among them, the “MEblue” module which had a highly positive correlation with ICA (R = 0.92, P = 4e-04). KEGG analysis showed that related genes were significantly enriched in the “Plant hormone signal transduction (ko04075)” pathway. YUC (a flavin-containing monooxygenase), AUX1, AUX/IAA, and ARF were identified as hub genes, and gene expression analysis showed that the expression levels of these hub genes under blue light were higher than those under white and red light. In addition, we also identified 6 auxin transport-related genes, including PIN1, PIN3, PIN4, PILS5, PILS6, and PILS7. Except PILS5, all of these genes showed the highest expression level under blue light. In conclusion, this study elucidated the molecular mechanism of light quality regulating adventitious root formation of tea short cutting through WGCNA analysis, which provided an innovation for “rapid seedling” of tea plants.

This thesis reports an investigation into the use of mobile air quality measurements to better understand urban traffic emissions. As part of the Breathe London project, two Google Street View Cars (based at the National Physical Laboratory) were fitted with air quality monitoring instrumentation and were driven across London over approximately a one year period. These mobile laboratories used a range of reference standard techniques to measure particulate matter and pollutant gases nitric oxide (NO), nitrogen dioxide (NO���), ozone (O���). Carbon dioxide (CO���) was also measured as an atmospheric tracer linked to vehicle and other combustion related emissions. The investigation begins with a characterisation and performance evaluation of the instrumentation, progressing to the development and deployment of advanced source apportionment techniques (scale separation and emission ratios) to extract the maximum information from the dataset. This study collected size-speciated particulate measurements using a light scattering device, black carbon using an aetholometer and Lung Deposited Surface Area (LDSA) using a diffusion-charging instrument. The performance of the instruments was compared using the mobile dataset. Significant amounts of close-to-source pollution were effectively measured using black carbon and LDSA (diffusion-charging) measurements. However, it was found that light scattering based particle counters were unable to measure significant amounts of pollution when measuring close to certain tailpipe emission sources. Techniques to differentiate between local emissions and a well mixed background from time series measurement signals were compared as part of the development of techniques to extract emission ratios. Whilst two distinct distributions (a low distribution for the petrol fleet compared to a higher distribution for the diesel fleet) may have been expected in the NOx emission ratio, consistently only a single distribution was seen. A time series simulation showed that the ability to resolve two separate (petrol and diesel) distributions in the emission ratio distribution was lost with increasing fleet density, due to atmospheric mixing. Emission ratios calculated with mobile data showed downward trends in NOx, black carbon and LDSA over the sampling campaign period., EPSRC iCASE Studentship, sponsored by the National Physical Laboratory

A series of novel thioether andrographolide derivatives were synthesized by incorporating various aromatic (or heteroaromatic) substituents into C-12 or 14-OH. A total of 38 andrographolide derivatives were prepared and evaluated for their in vitro inhibitory activity against cancer cells. All the derivatives exhibited better activity against prostate cancer cells (PC-3) than the parent compound. Among these, compounds 6a, 8, 9, 17, 19, 31, and 32 demonstrated good activity. These compounds were further evaluated for their anticancer activities against other cancer cell lines including MCF-7, MDA-MB-231, and A549. Compounds 31 and 32 showed excellent activity against MCF-7 with an IC50 value of 0.7 and 0.6 μM, respectively. The absolute configuration of 15a was determined via single-crystal X-ray diffraction. The activity of 6a (12S), which was the precursor of 15a, was better than that of the diastereoisomer 6b (12R). Moreover, the preliminary structure–activity relationship has been summarized. The results obtained herein are very important for further optimization of andrographolide.