Physiological Responses of Synechocystis sp PCC 6803 under Clinorotation

Photosystem efficiency and the characteristic on oxidative stress were examined to elucidate the metabolic responses of Synechocystis sp. PCC 6803 to short-term clinorotation. Results compiled when using clinostat to simulate microgravity for 60 h, showed that clinorotation clearly prohibited the photochemical quantum yield, but promoted the synthesis of chlorophyll and total protein. This may be a compensatory mechanism for the algal cell to maintain its normal metabolism. An increased malondialdehyde (MDA) content of algal cell upon clinorotation, together with an enhanced catalase (CAT) activity was observed during the whole period of clinorotation. One conclusion is that short-term clinorotation acts as a kind of stress, and that these physiological responses may be a special way for an algal cell to adapt itself to a different environment other than earth gravity.Photosystem efficiency and the characteristic on oxidative stress were examined to elucidate the metabolic responses of Synechocystis sp. PCC 6803 to short-term clinorotation. Results compiled when using clinostat to simulate microgravity for 60 h, showed that clinorotation clearly prohibited the photochemical quantum yield, but promoted the synthesis of chlorophyll and total protein. This may be a compensatory mechanism for the algal cell to maintain its normal metabolism. An increased malondialdehyde (MDA) content of algal cell upon clinorotation, together with an enhanced catalase (CAT) activity was observed during the whole period of clinorotation. One conclusion is that short-term clinorotation acts as a kind of stress, and that these physiological responses may be a special way for an algal cell to adapt itself to a different environment other than earth gravity

RpaA Regulates the Accumulation of Monomeric Photosystem I and PsbA under High Light Conditions in Synechocystis sp PCC 6803

The response regulator RpaA was examined by targeted mutagenesis under high light conditions in Synechocystis sp. PCC 6803. A significant reduction in chlorophyll fluorescence from photosystem I at 77 K was observed in the RpaA mutant cells under high light conditions. Interestingly, the chlorophyll fluorescence emission from the photosystem I trimers at 77 K are similar to that of the wild type, while the chlorophyll fluorescence from the photosystem I monomers was at a much lower level in the mutant than in the wild type under high light conditions. The RpaA inactivation resulted in a dramatic reduction in the monomeric photosystem I and the D1 protein but not the CP47 content. However, there is no significant difference in the transcript levels of psaA or psbA or other genes examined, most of which are involved in photosynthesis, pigment biosynthesis, or stress responses. Under high light conditions, the growth of the mutant was affected, and both the chlorophyll content and the whole-chain oxygen evolution capability of the mutant were found to be significantly lower than those of the wild type, respectively. We propose that RpaA regulates the accumulation of the monomeric photosystem I and the D1 protein under high light conditions. This is the first report demonstrating that inactivation of a stress response regulator has specifically reduced the monomeric photosystem I. It suggests that PS I monomers and PS I trimers can be regulated independently for acclimation of cells to high light stress.The response regulator RpaA was examined by targeted mutagenesis under high light conditions in Synechocystis sp. PCC 6803. A significant reduction in chlorophyll fluorescence from photosystem I at 77 K was observed in the RpaA mutant cells under high light conditions. Interestingly, the chlorophyll fluorescence emission from the photosystem I trimers at 77 K are similar to that of the wild type, while the chlorophyll fluorescence from the photosystem I monomers was at a much lower level in the mutant than in the wild type under high light conditions. The RpaA inactivation resulted in a dramatic reduction in the monomeric photosystem I and the D1 protein but not the CP47 content. However, there is no significant difference in the transcript levels of psaA or psbA or other genes examined, most of which are involved in photosynthesis, pigment biosynthesis, or stress responses. Under high light conditions, the growth of the mutant was affected, and both the chlorophyll content and the whole-chain oxygen evolution capability of the mutant were found to be significantly lower than those of the wild type, respectively. We propose that RpaA regulates the accumulation of the monomeric photosystem I and the D1 protein under high light conditions. This is the first report demonstrating that inactivation of a stress response regulator has specifically reduced the monomeric photosystem I. It suggests that PS I monomers and PS I trimers can be regulated independently for acclimation of cells to high light stress

Modeling of non-point source nitrogen pollution from 1979 to 2008 in Jiaodong Peninsula, China

Efforts to reduce land-based non-point source (NPS) pollutions from watersheds to coastal waters are ongoing all around the world. In this study, annual yield of NPS nitrogen (NPS-N) pollution in Jiaodong Peninsula, China from 1979 to 2008 was estimated. The results showed that: from 1979 to 2008, NPS-N yields exhibited significant inter-annual variations and an increasing trend on decadal scale. High NPS-N yield was mainly found in east and south parts, as well as the urbanized coastal regions in Jiaodong Peninsula. Among the 32 river basins, the three largest basins yielded more than 41.16% of the NPS-N. However, some small coastal watersheds along the South Yellow Sea and Jiaozhou Bay had higher per unit area yield. Most of the small watersheds characterized by seasonal runoff had coastal waters pertain to mild and moderate pollution levels. The ratio of watershed area to shoreline length and the up-stream land use had significant impacts on NPS-N flux through the shoreline. Among the four adjacent coastal areas of Jiaodong Peninsula, Jiaozhou Bay was the most noteworthy one not only because of high levels of land-based NPS-N pollution but also because of its nearly enclosed structure. The combination between integrated coastal zone management and integrated river basin management, land use planning and landscape designing in Jiaodong Peninsula is recommended. Copyright (c) 2013 John Wiley & Sons, Ltd.Efforts to reduce land-based non-point source (NPS) pollutions from watersheds to coastal waters are ongoing all around the world. In this study, annual yield of NPS nitrogen (NPS-N) pollution in Jiaodong Peninsula, China from 1979 to 2008 was estimated. The results showed that: from 1979 to 2008, NPS-N yields exhibited significant inter-annual variations and an increasing trend on decadal scale. High NPS-N yield was mainly found in east and south parts, as well as the urbanized coastal regions in Jiaodong Peninsula. Among the 32 river basins, the three largest basins yielded more than 41.16% of the NPS-N. However, some small coastal watersheds along the South Yellow Sea and Jiaozhou Bay had higher per unit area yield. Most of the small watersheds characterized by seasonal runoff had coastal waters pertain to mild and moderate pollution levels. The ratio of watershed area to shoreline length and the up-stream land use had significant impacts on NPS-N flux through the shoreline. Among the four adjacent coastal areas of Jiaodong Peninsula, Jiaozhou Bay was the most noteworthy one not only because of high levels of land-based NPS-N pollution but also because of its nearly enclosed structure. The combination between integrated coastal zone management and integrated river basin management, land use planning and landscape designing in Jiaodong Peninsula is recommended. Copyright (c) 2013 John Wiley & Sons, Ltd

Influence of liquid-binder ratio on the performance of alkali-activated slag mortar with superabsorbent polymer

The influences of liquid-binder ratio and mixing sequence on the performance of superabsorbent polymer (SAP)-containing alkali-activated slag (AAS) mortar are investigated in this study. It is found that the SAP absorbs much less liquid in upper supernatant of AAS than in water. Mixing SAP with liquid first induces a larger absorption capacity of the SAP than mixing it with solid first. Increasing the liquid-binder ratio improves the flowability but reduces the strength of AAS mortar with SAP. Nonetheless, the strength of internally cured mixtures is higher than that of the reference even with an extra liquid-binder ratio of 0.09. The reason behind lies in the refinement of capillary and gel porosity by internal curing, despite the presence of large voids originated from SAP. The autogenous shrinkage of AAS paste is reduced significantly by the incorporation of SAP but the further mitigating effect of increased liquid-binder ratio is limited.Materials and Environmen

Effect of superabsorbent polymer introduction on properties of alkali-activated slag mortar

Internal curing by superabsorbent polymer (SAP) has been applied in alkali-activated slag (AAS) systems by a few previous studies with the purpose to mitigate the autogenous shrinkage. However, the effects of SAP on other properties of AAS have been rarely studied. In this paper, the workability, strength, permeability, and frost resistance of AAS mortar with synthesized SAP are investigated besides the autogenous shrinkage. Two SAP introducing ways (dry mixing and wet mixing) are considered. It is found that the flowability of AAS mortar decreases with the increase of SAP dosage regardless of the introducing way. The strength and permeability increase with the SAP dosage when it is below a certain amount depending on the mixing way. The autogenous shrinkage can be mitigated significantly by the incorporation of SAP and the mitigating effect is more pronounced by wet mixing. The frost resistance becomes better when more SAP is introduced in either way. The mechanisms behind these phenomena are explained based on the characterization results on the reaction kinetics, reaction products and pore structure of the mixtures with SAP.Materials and Environmen

柯九思墨竹作品之研究

[[abstract]]本論文以「墨竹」作為探討之範疇，重新檢視柯九思之墨竹畫蹟，以之為研究中心。 由「墨竹」主題所象徵「全德君子」之寓喻為起點，企圖去回溯「墨竹」主題長期以 來之演變，藉以採討元朝畫家作墨竹題材之真正核心；並直接從柯九思之題畫詩和當 代文集中之題跋。以期瞭解擁有鑑畫博士頭銜的柯九思如何經由墨竹主題之製作，實 踐書法入畫之理論，完成其結合書畫合一之理想。 因此在第一章中利用資料的確認與再發現，重建柯九思之生平，企圖對他的生平與書 法入畫的理論，置於當時之脈絡下，作一深入討論。 第二章經由摘要式之敘述，分析柯九思以前長期以來墨竹題材之傳統，透過這些早期 墨竹名家之畫史著錄與其墨竹作品之類型分析，提供了研究柯九思書法入畫理論的有 用背景。 第三章旨在尋繹柯九思書法入畫之本質，希圖推溯柯九思所以書法入畫之緣由，以及 追索造成柯九思仿文同墨竹圖之意圖與「竹譜」製作之原因作為討論重點。 很明顯地，經由這些研究之後，可發現柯九思墨竹作品中書法入畫之表現功能，實深 切地傳達出趙孟頫書畫同源，用筆局法理想化之極致。這也是本論文選擇柯九思之墨 竹作品以討論書法與繪書間之關係的主要原因。

林德曼成人教育思想之研究

[[abstract]]本研究以文獻分析法分析、探討並批判林德曼的成人教育思想，以瞭解林德曼成人教 育思想的特色，並就林德曼思想的啟示，作為我國推展成人教育的參考。具體而言， 本研究的目的如下： 一、探析林德曼成人教育思想體系的形成過程。 二、分析林德曼成人教育思想體系的內涵。 三、批判林德曼成人教育思想體系的內涵。 四、探討林德曼成人教育思想對美國的影響。 五、針對林德曼成人教育思想對的研究結果，提供我國成人教育實務推展與理論研究 的參考。 本研究的重要結論如下： 一、林德曼的成人教育思想主要受到三方面的影響： (1) 探究團體的激盪；(2) 杜威及實用主義思想；(3) 葛龍及丹麥民眾高等學校運動 。 二、林德曼成人教育思想的內涵包括四方面：(1) 本質及目的論：成人教育是基於一 種動態的知識觀，將生活中的經驗融入教育之內，透過面對有關情境的學習，以達成 個人成長和社會進步；(2) 目標過程模式：智慧、權力、自我表達及自由，是成人教 育所要達成的基本目標，而健全的人格以及創造的實現，乃是成人教育的終極目標； (3) 課程論：工人教育應注重工人人格的培養。休閒教育應該盡量生活化，並重視心 靈的滿足。藝術教育應該和生活結合，並重視本土文化的民俗藝術；民主教育應對民 主的定義重新釐清，並傳遞民主的原則與價值；(4) 教學方法論：討論法是最好的成 人教育教學方法之一，雖有兼顧成員需求和團體目標、減少偏見及專家意見偏頗等優 點，但亦有其限制。 三、林德曼成人教育思想的影響是多方面的：(1) 在人物方面：對諾爾斯的影響包括 ：自我導向的、經驗的，以及問題解決的成人教育方法等。對海倫貝克的影響包括： 成人教育以社區為基礎的觀念、成人教育在國際事務上扮演的功能，以及成人教育和 民主的關係。對波威爾的影響則在討論法的觀念上；(2) 在美國成人教育實務上：對 公共政策的影響：透過成人教育促進民主和世界和平。對成人教育組織的影響：提供 社區發展的成人學習方案，並提供多元的成人學習機會。對成人教育課程的影響：建 立符合民主價值的課程、消除對無學分課程的輕視。對成人教育教學的影響：注重學 習者間的互動、鼓勵個別化的學習。對成人學習者的影響：學習者有權決定學習內容 和方法。 綜合言之，本研究認為林德曼成人教育思想的特色有十： 一、建立批判的成人教育觀。 二、提出解放的成人教育觀，重視人格教育。 三、重視經驗在成人學習中的重要性。 四、以個人成長和社會進步為成人教育的目的。 五、提倡以情境為基礎的成人教育法。 六、視成人教育為一種社會運動。 七、認為成人教育可以促進民主的實現。 八、強調成人教育具有非職業教育的特性。 九、具有「平等主義」的成人教育觀。 十、強調社區是推展成人教育的基礎。 根據林德曼成人教育思想的特色，可以發現林德曼思想對我國成人教育的啟示有九： 一、加強成人教育哲學思想的研究。 二、透過成人教育促進政治民主化以及國家發展。 三、加強對於成人教育的科際整合之研究。 四、建立以「經驗」為基礎的成人教育模式。 五、建立「批判思考」的成人教學模式。 六、重視成人人格的教育。 七、規劃以社區為基礎的成人教育方案。 八、成人教育政策應該兼顧個人需求和社會需求。 九、成人職業教育不應該偏重技術和指導。

Real-time reconstruction of unsteady rotating forces acting by rotor blades in moving medium

A time-domain inverse aeroacoustic method based on the convective Ffowcs Williams–Hawkings equation is presented. The method allows to determine, in real-time, the unsteady forces exerted on rotating blades in the presence of a moving medium. The inversion procedure is based on a space-time regularization with a mixed l1,2-norm, which guarantees accuracy and smoothness of the solution. The method is initially verified through synthetic acoustic signals emitted by rotating sources in a constant flow, up to a convective Mach number of about 0.88. Then the method is validated through signals generated by a propeller immersed in a wind-tunnel jet flow, up to a Mach number of 0.06. Due to the reduced convective Mach number, the leading aeroacoustic effect is derived from a variation of the blade loading. It is argued that the onset of flow separation at high values of the rotor advance ratio is responsible for the onset of force fluctuations that the inverse method is able to retrieve both qualitatively and quantitatively.Wind Energ

Effects of Ultrafine Blast Furnace Slag on the Microstructure and Chloride Transport in Cementitious Systems under Cyclic Drying–Wetting Conditions

This paper presents experimental investigations into the effects of ultrafine blast furnace slag on microstructure improvements against chloride penetration in saturated and unsaturated cementitious systems exposed to cyclic drying–wetting conditions. The hydration kinetics of ultrafine slag powders and pore solution chemistry in slag-blended cementitious systems at different ages, together with the main hydration products and pore structure characteristics, were determined. The chloride profiles accounting for different slag contents and drying–wetting cycles were measured. The results reveal that the reactivity of ultrafine slag can be well described with Avrami’s equation. The dilution effect of the slag predominated the pore solution chemistry, and the pH value decreased with a higher inclusion of slag. An optimal inclusion of 65% slag by mass of the binder corresponding to the finest pore structure and highest hydrotalcite content was found, which provides a reasonable basis for the slow chloride diffusion and high chloride binding. Under drying–wetting exposure, the specimen with a lower saturation exhibited a higher chloride transport caused by capillary absorption in the skin layer. The chloride transport tended to be diffusion controlled after sufficient drying–wetting cyclesMaterials and Environmen