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Control of pigment granular migration in the retinula of oriental fruit fly (Bactrocera dorsalis) by nitric oxide
No full text一氧化氮(nitric oxide, NO)為一種半衰期短暫的不穩定氣體分子。在生物體內由一氧化氮合成酶(nitric oxide synthase, NOS)產生，作用於標的細胞內的水溶性鳥苷酸環化酶(soluble guanylyl cyclase, sGC)，以提升細胞內cyclic GMP的含量。NO在昆蟲的中樞神經系統，被學界推測與嗅覺及視覺的形成過程有關，然而NO在昆蟲視覺系統真正的生理功能及作用機制仍有待證實。本研究以NADPH-diaphorase標定東方果實蠅(Bactrocera dorsalis)複眼中的NOS。在初級色素細胞及基底膜相鄰細胞標定出具有活性的NOS。而此兩處的細胞，相較於視官柱體(rhabdome)，含有較多的色素存在。為了驗證NO在此是否與昆蟲視網膜色素的調控有關，以NO生成劑(GSNO)及NO清除劑(C-PTIO)注入東方果實蠅視網膜內，觀察光適應時複眼偽瞳孔(pseudopupil)光影因視網膜細胞內色素顆粒移動所造成的變化。以GSNO處理的視網膜，偽瞳孔光影亮度減弱，在光刺激下視網膜仍保持暗適應的狀態；而對照組維持正常，表示NO的確可影響視網膜細胞內色素顆粒的移動。由本研究的結果推論，NO可由在東方果實蠅的視網膜產生，並且藉由調整色素顆粒的移動而改變其視網膜對光暗的適應狀態。Nitric oxide (NO) is an unstable gas molecular with short half-life. In organism, NO is produced by nitric oxide synthase (NOS), affects on the soluble guanylyl cyclase (sGC) of target cells, and lead to the increase of cyclic GMP level. In insect central nervous system, NO is supposed to have some physiological functions related to the olfaction and vision. However, the real function and mechanism of NO still need to be proved. In this study, NADPH-diaphorase was used to detect the expression of NOS in the compound eye of oriental fruit fly (Bactrocera dorsalis). The existence of NOS in the primary pigment cell and around the basement membrane was observed. Compare with the rhabdome, these two areas contain more pigments. To verify the relationship between NO and the pigments of insect retinula, the NO donor (GSNO) and the NO scavenger (C-PTIO) were injected into the retinula, and to observe the pseudopupil reflection caused by the migration of the pigment granules in light-adapted retinula cells. The pseudopupil reflection decreased in GSNO treatment group, and the retinula was kept in dark-adaptation with light stimulation, indicating that NO control the pigment granule migration in the retinula cells. According to these results, it is concluded that NO can be produced from the retinula of oriental fruit fly and control the light/dark-adaptation of retinula by regulating the migration of the pigment granules
Differential Identities with Engel Conditions
No full textThis thesis focuses on kernel inclusions of algebraic automorphisms, generalized derivations with Engel conditions and generalized derivations cocentralizing polynomials. In Chapter 1 we consider algebraic automorphisms with kernel inclusions. Let R be a prime ring. For an automorphism σ of R we let R(σ) def. = {x ∈ R | σ(x) = x}. Assume that σ is algebraic. We characterize the automorphism τ of R such that R(σ) ⊆ R(τ).
In Chapters 2,3 and 4 we consider certain identities with generalized derivations. Firstly, we concern generalized derivations cocentralizing polynomials. Let R be a prime ring with extended centroid C and let f(X1, . . . ,Xt) be a polynomial over C with zero constant term. Let D and G be generalized derivations of R. We characterize D,G and f(X1, . . . ,Xt) satisfying
D(f(x1, . . . , xt))f(x1, . . . , xt) − f(x1, . . . , xt)G(f(x1, . . . , xt))∈ C for all x1, . . . , xt in R.
Secondly, we consider certain Engel conditions on polynomials with generalized derivations. Precisely, we characterize D and f(X1, . . . ,Xt) such that the following Engel identity is satisfied:
[D(f(x1, . . . , xt)), f(x1, . . . , xt)]k= 0
for all x1, . . . , xt in R.
At the end, we concern a generalization of the previous two situations. Precisely, we characterize D,G and f(X1, . . . ,Xt) satisfying
[D(f(x1, . . . , xt))f(x1, . . . , xt)−f(x1, . . . , xt)G(f(x1, . . . , xt)), f(x1, . . . , xt)]k= 0
for all x1, . . . , xt in R
Use of Lightweight Aggregate in Plate Immobilized Biological Process for Removing Carbon and Nitrogen from Wastewater
No full text固定化生物技術發展單槽式處理程序整合硝化與脫硝於單一槽體進行反應，具有高碳、氮去除效率、佔地面積小及污泥產量少等優勢，可提升或改善傳統生物脫氮程序之處理效率。目前使用的載體中主要分為天然載體及合成載體兩類，天然載體容易為生物所分解之缺點，而合成載體於製備時須使用大量化學溶劑，一來具有毒性，二來對於環境造成不良影響。 為符合永續發展之理念，本研究採用環境友善之固化材料及經高溫燒結之輕質性骨材進行固定生物包埋，其中添加輕質性骨材為提升載體透水率。載體型式以平板固定生物污泥板進行兩階段實驗，分別為載體材料基本特性及操作參數試驗，於基本特性又細分為平板製作條件試驗及溶出試驗，目的為建立初步製作方法及載體於水中之穩定性；操作參數試驗目的為以不同操作條件(水力停留時間及碳氮比)對於COD、硝化及總氮去除率之影響，討論改變固定化生物外型下是否影響其去除效率。 載體基本特性分析結果顯示其固定化平板污泥受外型影響，於壓力3000 kg/cm2與持壓30秒為較佳的製作條件。溶出試驗中，載體在第一天及浸泡24小時之後，其COD、導電度與pH皆呈現最高，其COD為250 mg/L；導電度為8.5 mS/cm；pH則為12.61，隨著浸泡天數增加COD、導電度及pH皆有逐漸減少溶出之效果。 操作參數顯示，碳氮比對於硝化及總氮去除率影響較大，碳氮比由C/N=4調整至C/N=12時，硝化效率由58%提升至63%，總氮去除率由41%提升至53%。而水力停留時間從HRT=6 hr提升至HRT=12 hr，COD去除率、硝化效率及總氮去除效率在三種水力停留時間差異不大。整體而言，若HRT=12、C/N=12，於連續曝氣模式下可獲得較佳的去除效率。Immobilization of microbial cells technology combined traditional nitrification and denitrification in one single cell process which had many advantages are high organic carbon and nitrogen removal efficiency, small space occupation and less sludge produced. It also can be improved organic and nitrogen removal efficiency simultaneously from an aerobic activated sludge process. Nowadays, the matrix of immobilized microbial cell can be categorized into two groups: natural and synthetic. The most material for immobilized microbial cell are divides into two categories: Natural and Synthetic. The defect of natural material is easily decomposed by microorganism. Synthetic materials in the process of production applied complex chemicals are adverse impact on the environment. For environment sustainable development, in this study used environmental friendly and lightweight aggregates for the production of microbial cell, and the lightweight aggregates are added to hydraulic conductivity. This research is consisted of two parts: analysis of the material characteristics and operation parameters test with a microbial cell plate. Production conditions test of prepared into flat sheet of plates and dissolution test for the purpose to realize the stability of the material. The operational aspect will focus on investigating nitrification, denitrification and total nitrogen removal efficiency under different operating conditions such as carbon vs nitrogen ratio (SCOD/N) and hydraulic retention time (HRT). The microbial cell plate is formed in pressure 3000 kg/cm² and holding over 30 seconds. The dissolution test shown that the microbial cell plate elute COD over 250 mg/L, conductivity over 8.5 mS/cm and pH over 12.61 after the first day. However, the elute concentration of COD, conductivity and turbidity are found to be stable after five days of test, pH remained over 12 after 20 days of elution. The SCOD/N mode shown that is an impact of the total nitrogen removal efficiency. Nitrification removal efficiency was increased from 58% to 63% and TN removal efficiency increased from 41% to 53% when SCOD/N was adjusted from 4 to 12. In conclusion, the optimum operating conditions is SCOD/N of 12, HRT of 12 hr., which resulted in 94% SCOD removal efficiency, 65% nitrification, and 60% TN removal efficiency
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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