氧化壓力影響基因轉換表現對脂肪分化之作用
細胞脂肪分化是造成肥胖、骨質疏鬆、和糖尿病的重要前置因素。我們若要維持良好身材又想省去減肥藥的問題,那麼我們必須了解造成脂肪化的原因,才可能擁有好的預防之道。利用人類骨髓間質細胞可以分化成骨質與脂肪等細胞的特性,我們研究氧化壓力對間質細胞\r Ras基因轉換表現後骨質與脂肪分化的影響。結果發現以添加超氧根 (O2-,l5nM)形成氧化壓力,可促進正常Ras基因表現的間質細胞朝骨質分化;相反地,超氧根會促進\r Ras基因突變而不表現的細胞,朝向脂肪分化的現象。進一步研究其作可原理,發現氧化壓力可促進 RaS蛋白質啟動細胞外訊息活化酵素(ERK),接著驅動骨質轉錄因子(CBFA1)表現,再到骨鈣蛋白質與骨結節形成。而抗氧化酵素(超氧根轉化酵素;SOD,5OOU/ml)的作用,可以抑制正常Ras基因細胞氧化壓力下骨質分化的進行;但不能防止氧化壓力促進Ras基因突變細胞,朝向脂肪分化的作用。總結而言:Ras基因的表現與否,是決定脂肪分化的關鍵切換點;也是影響氧化壓力對間質細胞朝骨質分化的樞紐。這種基因與氧化壓力互動影響骨質與脂肪分化的剖析,將有助於提醒人們:使用抗氧化劑來調節抗衰老、肥胖、和美容時,必須是在不同情況和不同基因體質的人,有所不同。
\r Human\r mesenchymal stem cells are able to differentiate into bone, muscle, cartilage or\r fat tissues. Our preliminary study with human mesenchymal cell line (HS-5) showed\r that HS-5 cells could differentiate to bone, cartilage and muscle but not fat cells\r as determined by histochemical staining of phenotypes. We have further studied the\r influence of oxidative stress on the switch between bone and fat cell differentiation.\r Results showed that oxidative stress started with exogenous superoxide, produced\r by the interaction of xanthine oxidase and hypoxanthine, promoted the differentiation\r of osteogenic lineage showing expression of osteocalcin and bone nodule formations.\r The mechanism was investigated and superoxide was found to induce ERK (extracellular\r regulated signal kinase) activation; and then the expression of osteogenic specific\r transcriptional factor (CBFA1). A plasmid containing ras-mutant (Ser 17 Asn) which\r can inactivate the expression of ERK was transfected into the HS-5 cells for studying\r the influence of oxidative stress on ras-mutated mesenchymal cells. Surprisingly,\r it was found that oxidative stress did not promote osteogenesis but it enhanced\r adipogenesis from the ras-mutated HS-5 cells. Further studies indicated that superoxide\r neither induced ERK activation nor CBFA1 expression, but it did enhance expression\r of adipogenic specific transcriptional factor (C/EBPα) and lipoprotein lipase in\r the ras-mutated mesenchvmal cells. Taken together, the study model to induce the\r bone cell differentiation from human mesenchymal stem cells may be employed to make\r bone cells for tissue engineering.
Bio-Conversion of TiO2/UV System Pretreated Rice Straw to Ethanol
1. Purpose of the research :\r One of the greatest challenges for 21st century society is to meet the growing energy demand for transportation, heating and industrial processes. U.S. and Brazil are currently converting corn starch and sugarcane juice into ethanol; however, these are edible products. To stop global warming and poverty, we tried to determine to develop new pretreatment method to produce biofuel using non-edible parts of agricultural products.\r 2. Procedures :\r For our research purpose, we conducted ‘Preparation of Rice straw - Powder’, ‘Pretreatment Method of Rice Straw and Statistical Optimization Using Response Surface Methodology’, ‘Enzymatic Hydrolysis for Saccharification of Pre-treated Rice Straw’, ‘Analyses of Pretreatment Efficiency and Production of Glucose and Xylose Using HPLC & TLC’, ‘Ethanol Fermentation and Recovery’, ‘Strain Improvement for Pichia’.\r 3. Data :\r For the first time, rice straw was pretreated in a novel manner using hypochlorite-hydrogen peroxide (Ox-B) solution. The optimum pretreatment condition was analyzed by response surface methodology and the pretreated rice straw was hydrolyzed using two kinds of enzymes. Following hydrolysis, Saccharomyces cerevisiae and Pichia stipitis were inoculated for ethanol production. The optimum condition was 60 min pretreatment using Ox-B solution containing 0.6% hypochlorite and 25% hydrogen peroxide for 1 g rice straw in 240 ml total reaction volume. The Ox-B solution treatment was an essential step for efficient hemicelluloase hydrolysis. Under these conditions, 406.8 mg glucose and 224.0 mg xylose were obtained from 1 g rice straw. The structural change of rice straw after pretreatment and enzyme hydrolysis was examined by scanning electron microscopy. With the 10% initial sugar concentration, the final ethanol concentration was about 3.46%, which is 90.5 % of stoichiometric and fermentation efficiency yield.\r 4. Conclusions :\r Rice straw was pretreated in a novel mean by using an Ox-B solution broadly used in potable water treatment. Pretreatment modified the structures of lignocelluloses. The Ox-B solution treatment was an essential step for efficient hemicelluloase hydrolysis. Pretreatment modified the structures of cell wall. Further optimization studies of the fermentation process and strain improvement research (for derepressed mutant) are in progress. In the future, I hope to see cultivators to move by the ethanol produced from rice straw and agricultural wastes.
台灣和東亞地區的氣候變遷
由人類活動造成的溫室效應可能導致地球溫度升高,聖嬰現象加劇等現象與災害,本文利用個氣候中心發展出的模式,推估台灣和東亞地區未來氣候變遷的情況,我們發現當大氣中的二氧化碳濃度增加為現在的1.9倍時,台灣地區的年平均溫度將升高0.85-2.50度C而東亞地區將會升高1.46-4.07度C,在同條件下個模式的平均推估量也顯示,台灣地區將每天增加0.10公厘的降水,而東亞地區每天將增加0.08公哩,我們希望這個研究結果可以做為其他相關研究的基礎,使大家提早因應未來氣候變遷所可能引發的種種變化;Greenhouse effect, incurred mainly by human activities may result in lots of phenomenon and damages such as the increasing of the world's average temperature and he aggravation f the "ElNino" effect. In this research, we simulate future metrological values by employing several simulation modes developed by different climate centers and predict future climate changes in Taiwan and East Asia area. We found that when the concentration of carbon dioxide exceeds 1.9 times than current value, the estimated range of the increased year-average temperature are0.85-2.5℃ and 1.46-4.07℃ for Taiwan and East Asia, respectively. Under the same condition, the ensemble mean reveals that the precipitation raises will be 0.1 and 0.08mm per day, for Taiwan and East Asia respectively. We hope our work can be the foundation of other related researches, and all the researches together can help for coping with possible damages caused by future climate changes.
遞迥數列及渾沌現象
給定一個P∈(0,1),令k0=0, p0=p,定義k1為能使 的最小正整數k,而 ; 相同的,對於給定的kn-1, kn 為能使的最小正整數k, 。若存在kn 使得,則稱p∈ In; 若對於所有n 與kn ,,則稱p∈ I∞。如此區間(0,1)可分解成集合I1,I2,…,I∞。
磁性流體可調性折射率特性之研究與應用
磁性流體(magnetic fluids)是一種含有磁性奈米粒子的液體,當磁場外加於磁性流體時,流體中各磁性奈米粒子的磁矩會沿外加磁場方向排列,而導致粒子間相互吸引,形成較大的磁性叢集,即所謂的磁鍊。當外加磁場增強,該磁鍊數會變多,並使磁性流體的折射率產生變化。磁性流體的折射率變化會隨外加磁場之變大而增大。本研究除探討磁性流體折射率受外加磁場控制的變化情形及其物理原由外,並進一步運用此特性研發可調性光纖「光調制器」 ,以探討磁性流體可調性折射率應用在光電元件上的可行性。A magnetic fluid is one kind of colloids which contain magnetic nano-particles. Under an external magnetic field, the magnetic moment of nano-particles is aligned along the direction of the external magnetic field. This leads to the agglomeration of magnetic particles and to form magnetic clusters under an external magnetic field. With the formation of the magnetic clusters, the refractive index of magnetic fluid is varied. The refractive index of magnetic fluid was found to increase under a higher magnetic field. In this work, In addition to investigating in detail the behavior of the field-dependent refractive index of the magnetic fluid, we also explore the relevant physical origins. Furthermore, the feasibility of developing fiber-optical modulators by utilizing the tunable refractive index of magnetic fluids is discussed.
氣流式薄膜測厚儀
醫學上的植皮手術成功率受皮膚厚度影響,皮膚愈薄癒合速度愈快,其中以取皮厚度介於0.05mm 到0.1mm 為佳。在實驗量測時,需要經過一連串繁複的薄皮標本製作,再放到光學顯微鏡下測量,這種厚度測量方式不但耗時,又因嚴重損毀皮膚而不精確。由於使用螺旋測微器做接觸式測量會有形變的問題,因此我們想做間接接觸式的測量,所以採用氣體為媒介,做非破壞性檢測膜厚,這對於在皮膚上的施力遠小於螺旋測微器或是接觸式膜厚計。我們設計一套三頭連管線,使用空氣為媒介,儀器運作原理為在管線一端針頭非常靠近被測物時,所流出的氣體會受到被測物阻礙產生反壓使管線內的壓力上升,導致連通於另一管路的氣泡指示計壓出氣泡,當氣泡為最大氣泡時(半球形)視為達到平衡狀態。實驗時先用已知厚度且不變形的蓋玻片來當作被測物,此時可以算出針尖至蓋玻片的實際距離做為參考值。在量測軟性薄膜時,設計上採用兩側雙針頭靠近軟性被測薄膜兩側以達到氣流氣泡平衡,這時使用螺旋測微器讀取兩針尖距離,減去已知參考值的兩倍距離,即可測出未形變的軟物質厚度。本研究開發一套能測量軟性薄膜的厚度裝置,尤其在皮膚厚度測定上,不但不會直接接觸標本造成損毀,並且能夠快速地測量出厚度值,此為本儀器的最大特色。The thickness of skin graft has deterministic influences on the success of graft surgery. Experimental measurements of skin graft thickness involve complicated specimen preparation processes followed by optical microscopic examination, which are time-consuming and may incur inaccuracy due to possible damage. Here we propose a novel method using air as the media to avoid direct contact of the measured object. The physical operation relies on the following principles: When the tip of a needle connecting to a catheter system is placed close to the object to be measured, the air pumped forward from the catheter system becomes impeded by the object. The resulting backflow pressure opposing the air flow causes an increase in air pressure within the catheter and inflates the bubble connected at the other end. Balance at maximal surface tension is attained when the bubble reaches its maximum volume in hemispherical shape. In practice, a two-needle design was used, each approaching simultaneously from each side of the object. A micrometer was then used to read the distance between the two needle tips, from which the film thickness was derived, subtracting the thickness of the air layer pre-calibrated using cover glass with known thickness. The system implemented was capable of measuring thickness on soft thin films with an accuracy of ± 0.001mm. In addition to rapid measurements with high accuracy, since the pressure exerted on the skin graft is much less than in conventional calipers requiring direct contact, our method has the unique non-distorted and non-destructive advantages.
蟋蟀的聲音分析與聲音行為探討
蟋蟀聲音與行為的關係密不可分。取北部四種蟋蟀樣本,以數位錄音筆錄製及電腦軟體分析蟋蟀的聲音,並用PCR技術萃取蟋蟀的粒線體DNA(16S)加以分析,藉此和傳統的形態學分類相互比較。結果發現蟋蟀聲音的頻率特性中主頻率的差異在親緣遠近有關聯性,但聲音的時間特性方面則沒有特定關聯,不過聲學分析圖仍可作為單一種的鑑定指標。此外,研究發現此4種蟋蟀的聲音頻率範圍有重疊現象,但主頻率、脈衝比、唧聲率及唧聲長不同,推測雌蟋蟀應是綜合這些特性辨別同種。另一方面,以黑蟋蟀作為研究對象,進行干擾實驗,觀察並繪製出其聲音行為模式; 並將此作為對照,結果發現蟋蟀的生殖行為主要受到雄蟋蟀的聲音支配,而雄蟋蟀則以嗅覺辨別雌蟋蟀位置,決定下一步行動,與視覺較無關係。 Cricket's voice is closely related to the behavior. We select four species of crickets from the northern Taiwan to study the acoustic and mating behaviors. The digital sound recorder and acoustic software are used to analyze their acoustic characters. Furthermore, the PCR technology is used to amplify and sequence parts of mtDNA sequences and the results were compiled as the comparison to the traditional morphological character. The result shows that the resolution in acoustic characters of main frequency, pulse number, chirp rate, and the length of chirp are different among four species, though the minor frequency pattern is overlapping. Moreover, we find that frequency characteristic difference among four species is partly related to their phylogenetic relationship, yet is not seen in time characteristic. It is obvious that difference of acoustic behavior can be regarded as identified index among species. Results of acoustic analysis impel us to infer that the female crickets take the comprehensive acoustic behavior to distinguish their specific male. In addition, behavior pattern and model of Gryllus bimaculatus are established as the comparison of interfering experiment is undertaken. Which results suggest that the mating behavior in cricket is dominated by males’ acoustic behavior, and is initiated by male’s olfactory sense rather than that of sight.
均相沉澱法製備CZA 觸媒之探討
本研究以均相沉澱法合成多成分的銅鋅鋁觸媒系統,並嘗試克服傳統共沉澱法的不均勻性且提高比表面積,過程中我們利用改變尿素濃度、水添加量、反應溫度與時間等四種變因成功合成出具有高活性的銅鋅鋁觸媒。研究得知最佳的合成條件為尿素3M 並添加三倍體積的水,在95°C 下反應2 小時。與傳統觸媒相比,均相反應合成的銅鋅鋁觸媒除了有較小的粒徑外,其還原溫度也較低,顯示較佳的觸媒活性。而在250°C 甲醇重組的製氫反應條件下,均相反應合成的銅鋅鋁觸媒也有較高的甲醇轉化效率、氫氣產生率以及CO2 的選擇率,而添加鈰與鋯可更進一步使觸媒活性再提升。未來除可利用此合成方法合成均勻性佳的多成份材料,亦可應用此高效能觸媒進行甲醇重組反應以產生氫氣提供燃料電池使用。; Multi-composition Cu-Zn-Al catalyst system was synthesized by homogeneous precipitation method. This method was anticipated to improve the homogeneity of metal mixing and to increase the surface area of catalyst derived by conventional co-precipitation method. In the research, we successfully synthesized Cu-Zn-Al catalyst with high activity by adjusting four experimental parameters -- urea concentration, water amount, reaction temperature and reaction time. The better catalyst can be obtained under urea concentration of 3M diluted by 3 times water, and the kinetics conditions of 95°C and 2h. Compared with the co-precipitation method, homogeneous precipitation method derived Cu-Zn-Al catalyst performed higher methanol conversion, hydrogen production rate and CO2selectivity under methanol reforming reaction at 250°C. Modifying the support by addition of Ce and Zr might further improve the activity of the catalyst. In the future, not only can this method apply on synthesizing other multi-composition materials with high homogeneity, but also the high performance catalyst can be used to do methanol reforming reaction in order to supply hydrogen on fuel cell.
Super Oil Absorbent Form Rubber Waste
There are three main threats that give disastrous outcomes to the ecosystem, oil spill in the open sea, non-biodegradable wrapping plastics and logging to accommodate the paper industry. The current oil absorbent available in the market nowadays are more of fibers with hydrophilic characteristics. As a result, the oil been absorbed cannot be reused and causing total lost to the oil companies. It is estimates that billions of Malaysian Ringgit(RM) lost due to this cause for the past ten years.\r The objective of this project is to produce oil absorbent that not only created from the Empty Fruit Bunch(EFB) as a recycling initiative but at the same time able to reuse back all the absorbed oil after that. On top of that to this, we also hope to produce a biodegradable wrapping paper from the same material.\r The initial step towards the production of this eco-absorbent is known as Compounding Process which involves the grinding of the EFB along with some used rubber. This is then followed by adding flour to the mixture and then cooked until it is matured. At the end of this process, the product is grinded into refined form. Based on the investigations conducted, this eco-absorbent able to absorb oil five times of its weight and using a minimal pressure, the absorbed oil can be recollected back hence use onwards without changing the oil physical or chemical properties.\r On the other hand, the eco-friendly wrapping paper made out of the same material also showed high durability and tensile index. In addition to this it also showed high flexibility folding index which enables this wrapping paper to be shaped and folded into various forms according to the customer needs. All of these positives characteristics suggest that this eco-friendly wrapping paper able to replace the conventional plastic wrapping paper available in the market nowadays.\r In conclusion, we are one step closer in reducing the environmental pollution by using the EFB to produce the eco-oil absorbent and wrapping paper that it’s not only stressed on recycling the waste materials and precious oil resources but at the same time helps to save billions of Ringgit by the oil companies.
聽聽貝多芬作品的下一代:將碎形及基因演算法應用於數位音樂產生器
本研究整合了碎形圖形的迭代運算方法與基因交配觀念來達到音樂創新,並透過音樂和諧性判別機制來提高創新音樂的悅耳程度。利用基因觀念之交配的方法來解決長短的問題。這個方法是把原始音符輸入後,找出它們的中心點,以這個中心點為準,其他的音符按照一定比例向外延展,成為新的迭代點。再利用這些迭代點,迭代出新的音符。把製造好的音符染色體放置到交配池中,以隨機的方式在交配池中選取其中之一個染色體進行交配的動作,此二音符染色體會交換彼此的基因,產生下一代新的代表音符長短之染色體,隨後以「模仿母體判斷式」來判斷這新一代的音樂是否與母體音樂相似,藉此淘汰掉「不肖的」下一代,而若新一代與母體的相似程度高的話,它的悅耳性相信也會相對提高。最後把這些技術應用於數位音樂創作,以衍生新穎應用與創新的結果。Fractals can be produced by IFS (Iterated Function Systems). By iterative computation of many times, we can obtain the similar graphics. In my research, the methods to generate the iterative algorithms were presented. In addition, I would discuss the regularity and the content as well as the properties of those digital patterns. At last, the advanced application of fractals to digital music pieces was presented. The program took a note of several measure of music as the beginning point, and made the IFS calculations for each new note in each measure. But there was no difference in beats if you just make the IFS iteration. So I changed the beats with genetic crossover method. In this research, the expression of the DNA to each beat of note was adopted. The same way, it took a note as a beginning point. And the system obtained the new DNA from the old notes for new ones randomly. After producing the new pieces of music, I want to know if it is good to listen. So I used the algorithm that checks the simulation to the shape of mother music. If its shape is similar to the mother music, the probability that the new music is pleasing may even increase. That would make a piece of brand new music. What I want to do in this research is improve the multiformity of music and find what the relationship is of ‘good music’ and mathematical algorithms