The assessment of humoral immunity in the vaginal mucosa of pregnant and non-pregnant women.

Thesis (M.Med.Sc.)-University of Natal, 2003.Mucosal surfaces are prominent in the gastrointestinal, urogenital, and respiratory tracts and provide portals of entry for pathogens. The mucosal immune system consists of molecules, cells, and organised lymphoid structures intended to provide immunity to pathogens that impinge upon mucosal surfaces. The aim of this study was to assess humoral immunity in the vaginal mucosa and compare this immune response to a systemic response. The use of commercially available tampons provided a self-administered, pain free method for the collection of vaginal secretions. To standardise specimens, a total protein determination was performed on vaginal secretions and on sera. All subjects were screened for sexually transmitted infections (STIs) using conventional and deoxyribonucleic acid (DNA) amplification tests. Immunoglobulin levels in vaginal secretions and in sera were quantitated using a quantitative sandwich enzyme- linked- immunosorbent assay (ELISA). The immunoglobulin levels quantitated were analysed on the basis of pregnancy status and the presence or absence of an STI. Immunoglobulin results for serum showed a significant increase in IgG and IgA in women with an STI regardless of pregnancy (p< 0.001). This study showed a decrease in vaginal IgG and IgA in women with an STI. Non-pregnant women with an STI had significantly lower levels of IgG and IgA in the cervico-vaginal secretions as compared to the controls (p=0.002 and p=0.0002 respectively). This was also observed in pregnant women (p= 0.03 and p< 0.001 respectively). IgM levels were mostly too low to be detectable but showed a tendency to increase in vaginal secretions of women with an STI. Pregnancy did not have an effect on immunoglobulin levels except for IgA. The effects observed were due to the presence of an STI. All the STI pathogens studied displayed a similar effect on immunoglobulin levels. Bacterial vaginosis, however, appears to exert an effect specifically on lowering IgG (p=0.008) in vaginal fluid and increasing IgG levels (p=0.008) in serum. Once a more complete understanding of the mechanisms associated with the host defence of the vaginal mucosa is obtained, specific immunotherapeutic strategies can be developed. A greater knowledge of host defence factors specific to the vagina will provide insights into understanding susceptibility to opportunistic infections and STIs

Investigation of tensile creep and tension stiffening behaviour for Ultra-High-Performance Fiber Reinforced Concrete (UHPFRC)

Ultra-high-performance fiber reinforced concrete (UHPFRC) has improved properties over conventional concrete, such as high tensile strength, greater compressive strength and enhanced post cracking characteristics. The steel fibers in UHPFRC are recognized as providing resistance to crack widening in tension zones because of the fibers bridge adjacent cracks, which consequently enhances the tensile performance. Although, UHPFRC is capable of resisting the induced tensile stresses, it has still limitations under sustained tensile loads. It is also not well understood whether these characteristics would resist the induced tensile stress over a longer period or if they would leave the serviceability of the structure at risk. Therefore, the research presented in this study is concerned with the time-dependent tensile behaviour of UHPFRC. The present study comprises of an experimental program based on the application of newly developed test rigs, preparation of the test specimens and investigations into the test results. The aims seek to provide an understanding of the instantaneous and time-dependent tensile behaviour of unreinforced and reinforced UHPFRC prisms. Instantaneous tensile tests were involved, applying axial tensile loads to UHPFRC prisms for both aged and unaged concrete. The time-dependent tensile behaviour of UHPFRC was investigated in terms of tensile creep and tension stiffening mechanisms under sustained tensile loads. The sustained tensile loads were considered as different percentages of cracking loads, such as 50% and 75% of the cracking loads of unreinforced UHPFRC specimens for the tensile creep test and 75%, 100%, 150%, and 200% of the cracking loads of reinforced UHPFRC specimens for the tension stiffening test. The cracking loads were determined from 28th day instantaneous tensile responses for both reinforced and unreinforced UHPFRC prisms. Two different test rigs were used to conduct the tensile creep and tension stiffening tests under sustained tensile loads. The rigs were modified to overcome the limitations identified through the critical literature review. The experimental results demonstrate that the tensile creep strain and tension stiffening mechanisms are greatly influenced by the shrinkage strain of UHPFRC. A significant portion of the measured total shrinkage was caused by autogenous shrinkage rather than drying shrinkage. The results demonstrate that higher sustained stress leads to higher tensile creep strain for the first 13 days, at a higher creep rate. Afterwards, the shrinkage strain dominates over the tensile creep strain. The extent of crack propagation and the deterioration of the bonds between the steel fibers and the cement matrix are also significantly affected by the sustained tensile loads.Thesis (MPhil) -- University of Adelaide, School of Civil, Environmental and Mining Engineering, 201

High-Spatial-Resolution Monitoring of Strong Magnetic Field using Rb vapor Nanometric-Thin Cell

We have implemented the so-called $\lambda$-Zeeman technique (LZT) to investigate individual hyperfine transitions between Zeeman sublevels of the Rb atoms in a strong external magnetic field $B$ in the range of $2500 - 5000$ G (recently it was established that LZT is very convenient for the range of $10 - 2500$ G). Atoms are confined in a nanometric thin cell (NTC) with the thickness $L = \lambda$, where $\lambda$ is the resonant wavelength 794 nm for Rb $D_1$ line. Narrow velocity selective optical pumping (VSOP) resonances in the transmission spectrum of the NTC are split into several components in a magnetic field with the frequency positions and transition probabilities depending on the $B$-field. Possible applications are described, such as magnetometers with nanometric local spatial resolution and tunable atomic frequency references.Comment: 12 page

Computational Prediction of Origins of Glycyrrhizae Radix From Liquid Chromatography Mass Spectra (summary)

報告番号: ; 学位授与年月日: 2011-09-27 ; 学位の種別: 修士 ; 学位の種類: 修士(科学) ; 学位記番号: 修創域第4110号 ; 研究科・専攻: 新領域創成科学研究科情報生命科学専

Feasibility study of ground palm oil fuel ash as partial cement replacement material in oil palm shell lightweight concrete / Mohammad Momeen Ul Islam

The fresh concrete properties and mechanical properties of oil palm shell concrete (OPSC) containing palm oil fuel ash (POFA) as partial cement replacement have been evaluated. The effects of POFA replacement levels of 0%, 5%, 10%, 15%, 20% & 25% under different curing regimes, namely air curing, full water curing and initial water curing were investigated. For the evaluation of fresh concrete properties various test like slump, vebe second, compaction factor and wet density test were performed. The highest 28-day compressive strength of 42 MPa was obtained for the OPSC containing 10% of POFA under continuous water curing condition. The results also denoted cost reduction about 14% is possible for concrete produced from POFA based OPSC. Conversely, the splitting tensile and flexural strengths of OPSC decreased when increased amount of POFA was used. For durability properties, POFA was used as at 0%, 10%, 30% and 50% as replacement of ordinary Portland cement (OPC) when the water binder ratio (w/b) was 0.3 and again, OPC was replaced at 0% and 70% by POFA with w/b of 0.4.Different w/b was enacted to assess the outcome of pozzolanic reaction of POFA for different mixes. The durability tests include water absorption, sorptivity, drying shrinkage, sulphate attack and rapid chloride penetration test (RCPT) for 28- and 90-day water cured specimens. The water absorption and sorptivity values increase with the increase of POFA content. POFA based OPSC showed good resistance to sulphate attack. The drying shrinkage of POFA based concrete was higher with the increase of POFA content. The highest chloride ion penetration of about 5960 coulomb was recorded for the mix with 30% replacement of cement by POFA and with the further more replacement, the RCPT values were positively decreasing. In view of the current criteria for a sustainable environmental benefits, green building rating systems, infrastructure, the use of industrial wastes such as POFA and OPS as binder and coarse aggregates, respectively could benefit the concrete industry