Pepper (Piper nigrum L.) is a high economic value plant species that brings the main income to the people at Loc Hung commune. So the pepper’s yield plays a significant role in people’s life in this region. To assess the influence of environmental factors on the growth and development of pepper, we need to analyse the structural characteristics of soil nematode communities in order to promptly detect the levels of parasitic nematodes infection as well as assessment of soil environment status based on nematode communities. Study results at five sampling stations are analyses of 30 genera of nematodes belonging to 6 major trophic groups (bacterial feeders, fungal feeders, algal feeders, omnivores, carnivores and plant parasites). Calculation results of indices such as SMI, SMI2-5, MI and PPI showed that soil nematodes community is very little affected by the bacteria feeder group and the rate of parasitic nematode pepper quite severe. Analysis of correlation between trophic groups showed that nematodes are sensitive to environmental factors. This means the potential use of nematodes as a biological indicator for soil quality is possible. / Hồ tiêu (Piper nigrum L.) là cây trồng có giá trị kinh tế cao và là nguồn thu nhập chính của người dân tại xã Lộc Hưng. Do đó, năng suất cây tiêu có ý nghĩa rất lớn đối với đời sống người dân trong vùng. Để đánh giá ảnh hưởng của các yếu tố môi trường lên sự sinh trưởng và phát triển của cây tiêu, cần phải phân tích đặc trưng cấu trúc quần xã tuyến trùng đất của vùng nhằm phát hiện kịp thời mức độ nhiễm tuyến trùng ký sinh trên hồ tiêu cũng như đánh giá nhanh hiện trạng môi trường đất dựa trên quần xã tuyến trùng. Kết quả nghiên cứu tại 5 điểm thu mẫu phân tích được 30 giống tuyến trùng thuộc 6 nhóm dinh dưỡng chính (ăn vi khuẩn, ăn nấm, ăn tảo, ăn tạp, ăn thịt và ký sinh thực vật). Kết quả tính toán các chỉ số ΣMI, ΣMI2-5, MI và PPI cho thấy quần xã tuyến trùng đất ở đây rất ít chịu ảnh hưởng của nhóm ăn vi khuẩn và tỷ lệ hồ tiêu nhiễm ký sinh khá nặng. Phân tích tương quan giữa các nhóm dinh dưỡng cho thấy tuyến trùng khá nhạy cảm với các yếu tố môi trường, điều này cho thấy tiềm năng sử dụng tuyến trùng như một sinh vật chỉ thị cho chất lượng môi trường đất.

The recent breakthroughs in genomics and molecular diagnostics will not be reflected in health-care systems unless the biogenetic or other nucleic acid-based tests are transferred from the laboratory to clinical market. Developments in microfabrication techniques brought lab-on-a-chip (LOC) into being the best candidate for conducting sample preparation for such clinical devices, or point-of-care testing set-ups. Sample preparation procedure consists of several stages including cell transportation, separation, cell lysis and nucleic acid purification and detection. LOC, as a subset of Microelectromechanical systems (MEMS), refers to a tiny, compact, portable, automated and easy-to-use microchip capable of performing the sample-preparation stages together. Complexity in micro-fabrications and inconsistency of the stages oppose integration of them into one chip. Among the variety of mechanisms utilized in LOC for cell lysis, electrical methods have the highest potential to be integrated with other microchip-based mechanisms. There are, however, major limitations in electrical cell lysis methods: the difficulty and high-cost fabrication of microfluidic chips and the high voltage requirements for cell lysis. Addressing these limitations, the focus of this thesis is on realization of cell lysis microchips suitable for LOC applications. We have developed a new methodology of fabricating microfluidic chips with electrical functionality. Traditional lithography of microchannel with electrode, needed for making electro-microfluidic chips, is considerably complicated. We have combined several easy-to-implement techniques to realize electro-microchannel with laser-ablated polyimide. The current techniques for etching polyimide are by excimer lasers in bulky set-ups and with involvement of toxic gas. We present a method of ablating microfluidic channels in polyimide using a 30W CO2 laser. Although this technique has poorer resolution, this approach is more cost effective, safer and easier to handle. We have verified the performance of the fabricated electro-microfluidic chips on electroporation of mammalian cells. Electrical cell lysis mechanisms need an operational voltage that is relatively high compared to other cell manipulation techniques, especially for lysing bacteria. Microelectro-devices have dealt with this limitation mostly by reducing the inter-distance of electrodes. The technique has been realized in tiny flow-through microchips with built-in electrodes in a distance of a few micrometers which is in the scale of cell size. In addition to the low throughput of such devices, high probability of blocking cells in such tiny channels is a serious challenge. We have developed a cell lysis device featured with aligned carbon nanotube (CNT) to reduce the high voltage requirement and to improve the throughput. The vertically aligned CNT on an electrode inside a MEMS device provides highly strengthened electric field near the tip. The concept of strengthened electric field by means of CNT has been applied in field electron emission but not in cell lysis. The results show that the incorporation of CNT in lysing bacteria reduces the required operational voltage and improves throughput. This achievement is a significant progress toward integration of cell lysis in a low-voltage, high-throughput LOC. We further developed the proposed fabrication methodology of micro-electro-fluidic chips, described earlier, to perform electroporation of single mammalian cell. We have advanced the method of embedding CNT in microchannel so that on-chip fluorescent microscopy is also feasible. The results verify the enhancement of electroporation by incorporating CNT into electrical cell lysis. In addition, a novel methodology of making CNT-embedded microfluidic devices has been presented. The embedding methodology is an opening toward fabrication of a CNT-featured LOC for other applications.

Tumours are characterised by unorganised vasculature, which often results in hypoxic regions. Hypoxia is a common cause for photon radiotherapy (RT) treatment failure, as hypoxic cells require up to 2-3 times higher doses compared to well-oxygenated cells for the same effect in terms of cell kill. The increase in dose that would be required to treat the tumours of cancer patients is limited by the radiation sensitivity of surrounding normal tissues. Using carbon ions instead of photons, the radiation dose can be conformed to the tumour to a much higher degree, resulting in an improved sparing of normal tissues. In addition, carbon ions have a much higher radiobiological effectiveness near the end of their range, which is positioned in the tumour. Also, the radiation modes of action leading to cell death when carbon ions interact with living tissues, are less sensitive to the oxygen status compared with the action modes of photons. The focus of this thesis lies in the development of models for the computation of the cell surviving fraction and tumour control probability (TCP) in hypoxic tumours after photon and carbon ion RT. The impact of fractionation was evaluated with regard to possible spatial changes in oxygenation, both for stereotactic body RT and for carbon ion RT. The feasibility of a method to determine and deliver the optimal photon dose for achieving a high TCP according to spatial variations in radiation sensitivity was evaluated in a treatment planning study. The radiobiological models were finally used for the theoretical quantification of the gain in using carbon ions instead of photons. The results show that there are great possibilities to increase the number of positive outcomes of radiation treatment of tumours if the key influential factors are taken into account, such as level and distribution of hypoxia, radiation quality and choice of fractionation schedule. / <p>At the time of the doctoral defence the following papers were unpublished and had a status as follows; Paper 3: Manuscript; Paper 4: Epubl ahead of print; Paper 5: Manuscript</p>

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15371号 / 工博第3250号 / 新制||工||1489(附属図書館) / 27849 / 京都大学大学院工学研究科機械理工学専攻 / (主査)教授 中部 主敬, 教授 小寺 秀俊, 教授 田畑 修 / 学位規則第4条第1項該当

Children with loss of control (LOC) eating and attention-deficit/hyperactivity disorder (ADHD) are at risk for excessive weight gain. However, it is unclear whether or not these children show disturbances in hunger and satiety regulation. The goal was to examine the food intake and sense of LOC over eating as well as LOC eating-related characteristics during test meal in children with LOC eating and ADHD. Children aged 8-13 y with LOC eating (n = 33), ADHD (n = 32), and matched healthy controls (n = 33), consumed a test meal consisting of their chosen lunch food, with the instruction to eat until feeling full. Sense of LOC over eating, desire to eat, feelings of hunger, and liking of food were repeatedly assessed during test meal. Children with LOC eating and ADHD did not show a higher food intake at maximum satiety compared to control children. Sense of LOC over eating was significantly higher in children with LOC eating compared to children with ADHD and matched controls. Secondary analyses revealed that children with LOC eating ate marginally faster than control children. Both children with LOC eating and ADHD reported greater desire to eat, feelings of hunger, and liking of food during test meal than control children. Even though the results did not reveal statistical evidence to support the assumption of a disturbed food intake in children with LOC eating and ADHD, LOC eating related characteristics were significantly higher in these children compared to the control children. Sense of LOC over eating was confirmed as a specific characteristic of LOC eating. The examination of behavioral indicators of hunger and satiety dysregulation should be complemented with physiological indicators in future research.

Developing microdevices on flexible material attracts scientific community to explore applications in different aspects of health and point of care diagnostics. Flexible substrates offer unique characteristics such as flexibility, stretchability, portability, low-cost, and simple fabrication. Fabrication of cost-effective paper-based analytical devices by wax printing has recently become popular using cellulose filter papers. Paper-based devices need higher temperature to form hydrophobic barrier across paper substrate, rely on large working channels (≥ 500 μm) for liquid handling, and exhibit lower efficiency (~50%) of sample mobility. Such limitations confine applications of wax-based fabrication. In this dissertation, we report printability, fidelity, and applications of wax micropatterns on polyethylene terephthalate-based substrate (PET), which is a a non-cellulosic, non-fibrous, and non-porous material. Resolution, sustainability against heat and biocompatibility was tested on wax micro-features. The patterned devices were explored for variety of applications.First, wax microwells on PET showed mouse embryonic stem cell (mESC) self-renewal or direct differentiation. Second, microfluidic flow was demonstrated on wax printed microchannels on PET which was used to develop distance-based assay. Third, fluidic properties of trinucleotide repeat sequences were investigated on wax microchannels. Fourth, multilayer wax-on-plastic device was fabricated using wax printing with hand painting of conductive materials for electrochemical immunosensing.

This study investigates the relationship between wave-induced hydrodynamics and the resulting loading on Core-Loc concrete armour units below the still water level in a breakwater structure. Physical modelling experiments were performed at the National Research Council in Ottawa in which a 3D-printed 12 cm Core-Loc armour unit was instrumented and fixed in place within a rubble mound structure. Testing featured simultaneous measurement of force on this instrumented unit, pressure head at the base of the unit, and flow velocities below the SWL. Two main scenarios were tested, the isolated unit and fully armoured scenarios, under a range of regular waves and irregular sea states. Analysis of force development on the instrumented unit indicates that maximum slope-normal forces (both into and away from the structure) are associated with extremes in pressure head above the instrumented unit, while slope-parallel force extremes (both upslope and downslope) occur at times of the fastest change in water level. These loadings are consistent with Morison’s equation and imply drag dominance in the slope-parallel direction and inertia dominance in the slope-normal direction. Significant differences in forces were observed between isolated (no neighbouring units) and embedded (with neighbouring units) armour unit test cases. The presence of the armour layer significantly increased the normal force exerted on the unit and reduced the parallel force. Irregular sea state testing shows force peaks following normal distribution. Analysis of flow above the armour layer showed that force, flow velocity and flow acceleration are symmetrical in the slope-parallel direction, but largely asymmetrical in the slope-normal direction, with the flow velocity and force on the unit in particular experiencing large asymmetries. Wave height analysis indicated that each wave height follows a similar force development pattern with a magnitude proportional to wave height. Wave period analysis showed the formation of small secondary waves as the period increases. Wave steepness affected the peak force loading of the instrumented unit in a mostly linear fashion up to the critical Iribarren number.

No description available.

Pepper (Piper nigrum L.) is a high economic value plant species that brings the main income to the people at Loc Hung commune. So the pepper’s yield plays a significant role in people’s life in this region. To assess the influence of environmental factors on the growth and development of pepper, we need to analyse the structural characteristics of soil nematode communities in order to promptly detect the levels of parasitic nematodes infection as well as assessment of soil environment status based on nematode communities. Study results at five sampling stations are analyses of 30 genera of nematodes belonging to 6 major trophic groups (bacterial feeders, fungal feeders, algal feeders, omnivores, carnivores and plant parasites). Calculation results of indices such as SMI, SMI2-5, MI and PPI showed that soil nematodes community is very little affected by the bacteria feeder group and the rate of parasitic nematode pepper quite severe. Analysis of correlation between trophic groups showed that nematodes are sensitive to environmental factors. This means the potential use of nematodes as a biological indicator for soil quality is possible. / Hồ tiêu (Piper nigrum L.) là cây trồng có giá trị kinh tế cao và là nguồn thu nhập chính của người dân tại xã Lộc Hưng. Do đó, năng suất cây tiêu có ý nghĩa rất lớn đối với đời sống người dân trong vùng. Để đánh giá ảnh hưởng của các yếu tố môi trường lên sự sinh trưởng và phát triển của cây tiêu, cần phải phân tích đặc trưng cấu trúc quần xã tuyến trùng đất của vùng nhằm phát hiện kịp thời mức độ nhiễm tuyến trùng ký sinh trên hồ tiêu cũng như đánh giá nhanh hiện trạng môi trường đất dựa trên quần xã tuyến trùng. Kết quả nghiên cứu tại 5 điểm thu mẫu phân tích được 30 giống tuyến trùng thuộc 6 nhóm dinh dưỡng chính (ăn vi khuẩn, ăn nấm, ăn tảo, ăn tạp, ăn thịt và ký sinh thực vật). Kết quả tính toán các chỉ số ΣMI, ΣMI2-5, MI và PPI cho thấy quần xã tuyến trùng đất ở đây rất ít chịu ảnh hưởng của nhóm ăn vi khuẩn và tỷ lệ hồ tiêu nhiễm ký sinh khá nặng. Phân tích tương quan giữa các nhóm dinh dưỡng cho thấy tuyến trùng khá nhạy cảm với các yếu tố môi trường, điều này cho thấy tiềm năng sử dụng tuyến trùng như một sinh vật chỉ thị cho chất lượng môi trường đất.

Diesel engines operating the rig pose the problems of low efficiency and large amount of emissions. In addition the rig power requirements vary a lot with time and ongoing operation. Therefore it is in the best interest of operators to research on alternate drilling energy sources which can make entire drilling process economic and environmentally friendly. One of the major ways to reduce the footprint of drilling operations is to provide more efficient power sources for drilling operations. There are various sources of alternate energy storage/reuse. A quantitative comparison of physical size and economics shows that rigs powered by the electrical grid can provide lower cost operations, emit fewer emissions, are quieter, and have a smaller surface footprint than conventional diesel powered drilling. This thesis describes a study to evaluate the feasibility of adopting technology to reduce the size of the power generating equipment on drilling rigs and to provide ?peak shaving? energy through the new energy generating and energy storage devices such as flywheels. An energy audit was conducted on a new generation light weight Huisman LOC 250 rig drilling in South Texas to gather comprehensive time stamped drilling data. A study of emissions while drilling operation was also conducted during the audit. The data was analyzed using MATLAB and compared to a theoretical energy audit. The study showed that it is possible to remove peaks of rig power requirement by a flywheel kinetic energy recovery and storage (KERS) system and that linking to the electrical grid would supply sufficient power to operate the rig normally. Both the link to the grid and the KERS system would fit within a standard ISO container. A cost benefit analysis of the containerized system to transfer grid power to a rig, coupled with the KERS indicated that such a design had the potential to save more than $10,000 per week of drilling operations with significantly lower emissions, quieter operation, and smaller size well pad.