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Background Internode elongation is one of the most important traits in sugarcane because of its relation to crop productivity. Understanding the microRNA (miRNA) and mRNA expression profiles related to sugarcane internode elongation would help develop molecular improvement strategies but they are not yet well-investigated. To identify genes and miRNAs involved in internode elongation, the cDNA and small RNA libraries from the pre-elongation stage (EI), early elongation stage (EII) and rapid elongation stage (EIII) were sequenced and their expression were studied. Results Based on the sequencing results, 499,495,518 reads and 80,745 unigenes were identified from stem internodes of sugarcane. The comparisons of EI vs. EII, EI vs. EIII, and EII vs. EIII identified 493, 5035 and 3041 differentially expressed genes, respectively. Further analysis revealed that the differentially expressed genes were enriched in the GO terms oxidoreductase activity and tetrapyrrole binding. KEGG pathway annotation showed significant enrichment in “zeatin biosynthesis”, “nitrogen metabolism” and “plant hormone signal transduction”, which might be participating in internode elongation. miRNA identification showed 241 known miRNAs and 245 novel candidate miRNAs. By pairwise comparison, 11, 42 and 26 differentially expressed miRNAs were identified from EI and EII, EI and EIII, and EII and EIII comparisons, respectively. The target prediction revealed that the genes involved in “zeatin biosynthesis”, “nitrogen metabolism” and “plant hormone signal transduction” pathways are targets of the miRNAs. We found that the known miRNAs miR2592-y, miR1520-x, miR390-x, miR5658-x, miR6169-x and miR8154-x were likely regulators of genes with internode elongation in sugarcane. Conclusions The results of this study provided a global view of mRNA and miRNA regulation during sugarcane internode elongation. A genetic network of miRNA-mRNA was identified with miRNA-mediated gene expression as a mechanism in sugarcane internode elongation. Such evidence will be valuable for further investigations of the molecular regulatory mechanisms underpinning sugarcane growth and development.

Composite beam-slab systems have been widely used in the modern building construction as they not only reduce the constructional cost, but also expedite construction schedule compared to traditional reinforced concrete slab systems. However, steel profiled decking and supporting steel beams are vulnerable under fire condition. It is necessary to provide sufficient fire protection materials to keep these components under certain temperature for a period of time. Fire protection is costly and sometimes not necessary. Through several large-scale fire tests conducted in Europe, despite of unprotected interior supporting steel beams, it is observed that composite beam-slab systems have a superior fire performance due to mobilisation of tensile membrane action. Therefore, the British Research Establishment (BRE) published SCI-P288 and SCI-P390 design guidelines for steel framed composite slabs by taking account of tensile membrane action at fire limit state. Since these two design guidelines were only validated through limited fire tests and focused on isolated composite slab panels, the proposed work seeks to examine these guides more deeply, especially with regard to deflection limit validation and continuity effects on the development of tensile membrane action. Three series of nine specimens with one-quarter scale composite slabs were fabricated and tested at elevated temperature in Nanyang Technological University. The main investigated parameters included structural continuity effect and aspect ratios (1 and 1.5). Compared with SCI-P288 and SCI-P390, the test results showed that this design method was conservative. Even at the defined deflection limits in the SCI-P288 and SCI-P390, there were still reserves for the load-bearing capacity of these specimens. To find out the development of membrane actions, numerical models were built up by ABAQUS. From the analyses, both compressive and tensile membrane forces were developed and the equilibrium was achieved by forming a tensile membrane zone in the middle surrounded by a peripheral compressive ring. Based on membrane forces distribution from the numerical analyses, a revised analytical model was proposed by incorporating the boundary restraint forces. Compared with the test results, the author's analytical model showed good predictions of the load-bearing capacity for composite slabs at the fire limit state by incorporating edge beams forces. Doctor of Philosophy (CEE)

In order to study the effects of seed soaking with Paclobutrazol (PP333) on the tillering and physiological characteristics of sugarcane seedlings, sugar cane variety ROC22 was used as experimental material. The effects of seed soaking with different concentrations of PP333 were studied. The tiller number and growth of sugarcane were surveyed at the 6-leaf stage, the physiological indicators such as chlorophyll content, soluble protein content, proline content and peroxidase activity were measured at the 2-leaf, 4-leaf, and 6-leaf stages. The results showed that the seed soaking with PP333 can effectively improve the tillering of sugarcane seedlings. The suitable concentration for the tillering of sugarcane and the growth and development of sugarcane was of 50 mg / L; the seed soaking with PP333 significantly increased the chlorophyll, soluble protein, proline, and peroxidase activity of leaves of sugarcane seedlings; the content of chlorophyll and soluble protein in leaves of sugarcane seedlings treated with 90 mg / L PP333 was the highest, and the proline content and peroxidase activity of sugarcane treated with 50 mg / L PP333 were the highest.

Raman spectroscopy was used to study red blood cells (RBCs) and blood in vein capillary, in artery capillary in vivo and in vitro with the use of optical tweezers. Results showed that, (1) We could get Raman spectroscopy of blood in vivo; (2) We could clearly observe that different blood spectra in. oxygenated and deoxygenated state in artery and vein capillary; (3) By studying Raman spectroscopy of single RBC, we concluded that the hemoglobin concentration in capillary was larger than that in vitro, and oxygenated Raman peak of RBC in artery capillary was More obvious than those in vein capillary; (4) By comparing Raman spectrum in vein with that in artery, we found that that pH value in artery capillary is higher than that in vein capillary, and by studying the change of the band at 1604 cm(-1), we found that the band change was in connection with the circumstance pH value around RBCs. These findings make it possible to study conformational changes within single cells in vivo. The experiments also have shown that laser tweezers Raman spectroscopy can provide a strong tool for research in vivo.

The measurement of blood glucose are enzymatic and biochemical methods which are destructive.Raman technique is used to detect blood glucose and a new data analysis method is established to analyse blood glucose concentration,which is a noninvasive and rapid blood glucose tests.Using mice as experimental models,Raman spectra of blood taken from the tails are acquried half an hour after injection of glucose.Raman spectra are collected every 15 minutes and accompanied by blood glucose meter to get the blood glucose value to be reference.1 125 cm-1 is characteristic peak of glucose and glucose in blood is called blood glucose,so 1 125 cm-1 is chosen as the peak of blood glucose in the Raman spectra of blood.1 549 cm-1 is characteristic peak of hemoglobin which is stable in the body,so 1 549 cm-1is used to be internal standard to research 1 125 cm-1 intensity.The result shows that the change of 1 125 cm-1/1 549 cm-1 may well correspond with changes in blood glucose and they have a good linear relationship.The experiments show that this Raman technique can reflect the changes of blood sugar levels noninvasive.

A novel techique of sorting yeast cell based on Raman characteritics of target products synthesized by microorganisms was developed by using Raman microspectroscopy coupled with optical manipulatation.To sort oleaginous yeast and carotenoid-producing yeast,the plant oil and β-carotene were chosen as the target products and their Raman characteritics,the intensity ratios of 1 440 cm-1 and 1 602 cm-1 band(i.e.I1440/I1602) for oil,and I1157/I1654 or I1520/I1654 for carotenoid,were extracted and marked as target cells.Single yeast cell was captured and manipulated by using a 780 nm laser,and the Raman spectra of trapping cell was acquired simultaneously.A real-time computer distinguishing program was used to assist the sorting.The distinguished cells were then extracted and validated by following culture and Raman detection.This work provides a new method for screening microorganisms synthesize products with economic value.

Raman tweezers is used to probe the oxygen carrying capacity of erythrocytes.The effects of laser power on erythrocytes are compared.An indicator for distinguishing oxygenated and deoxygenated erythrocytes is chosen and utilized to analyze the oxygen carrying capacity of erythrocytes from different storage time and different health state.The result shows that strong power of laser led to the bands at 1 248,1 371 cm-1,the markers of heme aggregation,increasing.The ratio I1 638/I1 547,a well indicator for distinguishing oxygenated state from deoxygenated state,reveals that the oxygen binding capacity of preserved erythrocytes increase as storage time extending,while the deoxidization capacity is not change significantly.Erythrocytes from HbH-CS,an alpha-thalassemia disease,are easier to oxygenate than normal controls,but difficult to deoxygenate.The findings demonstrate Raman tweezers can be a rapid,non-invasive,sensitive technique for analyzing and evaluating the oxygen carrying capacity of erythrocytes.

Real-time monitoring the gelatinization process of single rice starch particle using laser tweezers Raman spectroscopy system under the condition of excessive water and special heating mode is reported.These Raman spectra of gelatinization process are acquired using an imaging CCD spectrograph and the gelatinization process is remarked by the changes of spectra peak height.The experimental result further confirmed the fact that the band of 477cm-1 is assigned as skeletal mode.The rate of gelatinization about single rice starch granules is studied by analyzing the C-O-H group related characteristic peaks which locate at the band of 1 052,1 083,1 127,1 339 cm-1.The results demonstrate that the rate of gelatinization accelerates with rising temperature until the end of gelatinization process.