Symplectic Symmetry of the Neutrino Mass For Many Neutrino Flavors

The algebraic structure of the neutrino mass Hamiltonian is presented for two neutrino flavors considering both Dirac and Majorana mass terms. It is shown that the algebra is Sp(8) and also discussed how the algebraic structure generalizes for the case of more than two neutrino flavors.Comment: 6 pages, LaTeX, presented at Scandinavian Neutrino Workshop, Uppsala, February 8-10, 2001, to appear in the proceedings, Physica Script

Articulating Principals, Agents and Institutions in the EU

Principal agent problems arise frequently in situations of interdependence. Europe, with its various arrangements, is replete with principal agent problems that are mediated by institutions at various levels. While issues of water and land can provide a convenient focus, the essential problem is a deeper one. Decision making in principal agent situations has traditionally been considered in only a limited way. Current agency approaches seek to orient the interests of agents to those of the principal. More generalised formulations experience difficulties in reconciling interests. This is apparent not only in two-party forms but even more so in three-part(y) ones. In n-party environments things may appear to become simpler as n increases, but the problem may remain. An innovative exploration of a principal-agent situation which uses object-based concepts and simulations is presented in this paper. Different patterns of agent commitment are seen when it is applied to a European context. Suitable reconceptualisation of agency theory appears to have wide implications and applications. Its further development will allow more adequate specification of agency situations with immediate implications for policy and practice not only in Europe but in nations and regions around the world.

Team Effectiveness and Leadership Roles

In this study we aim to explain the patterns of leadership roles for team effectiveness in non economic organizations compared to economic organizations. For this purpose, we studied three successful organization types, i.e the amateur sports clubs (football, basketball), theater companies and, regional folk groups. Our basic hypothesis is that the relationship between the type of organization (specially teams) and the role of leadership is not random. Therefore, we believe that an empirical approach is necessary to test the assumptions about leadership and team effectiveness. Also these empirical results are supposed to lead to professional managers in economic organizations. First, we constructed thirteen key dimension variables for leadership behavior as follows: coaching, effective communication, encouraging teamwork, establishing high standards and getting results, effective delegation, rewarding performance, developing and releasing employees, building consensus, supporting reasonable risk- taking, forecast thinking, improving the organization, managing diversity, and overall effectiveness . Second, we defined team standards and effectiveness in twenty items. And finally, we tried to emphasize factors affecting leadership roles and team effectiveness. In this study, Natemeyer and Babko (1992) Management Practices Survey data are used. Data reliability are tested before the analysis and results are discussed at the end of the study.Team effectiveness, Leadership; Roles

Business Process Modeling for developing Process Oriented IT Systems

International audienceInformation system developers are challenged to develop systems that should meet the requirements of modern organizations. By promoting the enterprise-wide integration, the paradigm of Business Process Management contrasts with traditional information system development, which was suffered, but also crystallized, the vertical division of the enterprise activities. In addition, the paradigms of Business Process Reengineering and Business Process Improvement contrast with traditional information system development that focused on automating and supporting existing business processes. Now, enterprises should create new ways of working to survive in a competitive environment. This organizational transformation depends of the creation of a powerful vision of what future should be like. We claim that an in depth understanding of the current functioning is also required. In this context, enterprise modeling can help understanding the current business situation and establishing a vision of what the future should be like. Therefore, business process modeling becomes a pre-requisite for system requirements elicitation and system development

113 yıllık Cemilzade tadı

Taha Toros Arşivi, Dosya No: 112-Pastahaneler, Bozacılar, Gazozcular, Börekçiler, Turşucular, Sucularİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Development: What’s in a name?

The article looks into the process of the creation of development discourse in Turkey and its consequences on the field. In the first section of the article, amusing anectodes are given from 1990s during which this process unfolded and gave way to a “project industry” with the EU accession period in Turkey. The focus of the second part is on the evaluation of paradigm shift towards “human development”. Evaulation methods of development projects, numbers, statistics, indexes in this paradigm are critically interpreted. In the last part, field cases from Kavar Region, east of Turkey, are given in order to find answers to questions like what development means for Kavar and the relationship between happiness, dignity and development

A Scalable Null Model for Directed Graphs Matching All Degree Distributions: In, Out, and Reciprocal

Degree distributions are arguably the most important property of real world networks. The classic edge configuration model or Chung-Lu model can generate an undirected graph with any desired degree distribution. This serves as a good null model to compare algorithms or perform experimental studies. Furthermore, there are scalable algorithms that implement these models and they are invaluable in the study of graphs. However, networks in the real-world are often directed, and have a significant proportion of reciprocal edges. A stronger relation exists between two nodes when they each point to one another (reciprocal edge) as compared to when only one points to the other (one-way edge). Despite their importance, reciprocal edges have been disregarded by most directed graph models. We propose a null model for directed graphs inspired by the Chung-Lu model that matches the in-, out-, and reciprocal-degree distributions of the real graphs. Our algorithm is scalable and requires $O(m)$ random numbers to generate a graph with $m$ edges. We perform a series of experiments on real datasets and compare with existing graph models.Comment: Camera ready version for IEEE Workshop on Network Science; fixed some typos in tabl

Optimization Of Cultivation Conditions And Engineering By Random Mutagenesis For High Lipid Production In Schizochytrium Sp. S31

Tez (Doktora) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2016Thesis (Ph.D.) -- İstanbul Technical University, Institute of Science and Technology, 2016Schizochytrium sp. yüksek oranda çoklu doymamış yağ asitleri özellikle dokosaheksaenoik asit (DHA) elde etmek amacıyla yaygın olarak çalışılan mikroalgdir. Farmasötik hammadde, gıda katkısı, su kültürü ve hayvan yemi olarak kullanılan çeşitli biyoaktif bileşikler içerirler. Ayrıca alternatif enerji kaynağı olarak kullanılan biyoyakıt üretiminde önemli role sahiptir. Hızlı büyüyen ve yüksek DHA oranına sahip Schizochytrium sp. balık yağına alternatif olarak kullanılabilir. Bu çalışmada, Schizochytrium sp. S31 mikroalginin toplam biyokütle ve yağ oranını artırmak amacıyla hücre büyüme koşullarının tepki yüzey metodu ile optimizasyonu gerçekleştirilmiştir. Optimize edilen büyüme koşulları kullanılarak Schizochytrium sp. S31’in büyük hacimde üretimi gerçekleştirilmiş ve yüksek oranda yağ elde etmek amacıyla hücre parçalama, kurutma ve yağ ekstraksiyonu içeren akış proseslerinin karşılaştırılması ve optimizasyonu tamamlanmıştır. Son bölümde, ultraviyole (UV) ışın veya kimyasal mutajen kullanarak rastlantısal mutasyon uygulaması ve floresan sitometri yöntemiyle yüksek oranda yağ üreten Schizochytrium sp. mutantın seçilimi gerçekleştirilmiştir. Schizochytrium sp. üretimini besiyeri içeriği, pH, tuzluluk ve sıcaklık gibi birçok faktör etkileyebilir. Çoklu doymamış yağ asitlerinin insan sağlığı, endüstriyel ve ticari kullanımında önemli bir rol oynamasından dolayı biyokütle ve lipid üretiminin geliştirilmesi üzerindeki çalışmalar son zamanda artmıştır. Bu sebeple, besiyeri içeriği ve çevresel koşulların optimizasyonu, organizmanın biyokütlesinin ve toplam lipid içeriğinin geliştirilmesi için önemlidir. İstatistiksel yaklaşımlar, biyokütle üretim ve yağ ekstraksiyon optimizasyonu için uygun bir yol olmakla birlikte ürün verimliliğini artırarak üretim maliyetini düşürmüştür. Plackett burman ve merkezi kompozit tasarım gibi istatistiksel metotlar, çeşitli faktörleri ve onların birbiriyle etkileşiminin optimizasyonunda yaygın olarak kullanılmıştır. Plackett Burman tasarımı, biyoproseslerin optimizasyonunda belirlenen cevaplara etki eden faktörlerin tanımlanmasında ilk adım olarak kullanılır. En önemli faktörlerin seçimini takiben merkezi kompozit tasarımlı tepki yüzey yöntemi, bu faktörlerin optimum değerlerini tespit etmek amacıyla kullanılır. İstatistiksel analiz sonuçlarına göre, maksimum biyokütle (26.86g/L) üretimi, 2.29 g/l monosodyum glutamat (MSG), pH 5.8 yetiştirme koşulları ile elde edilmiştir. Maksimum lipid (% 35) üretimi 0.49 g.L-1 MSG, 17.6 °C sıcaklık koşullarında elde edilmiştir. Schizochytrium sp. S31, şeker, organik asitler ve alkol gibi alternatif hammaddeler kullanılarak biyoreaktörde heterotrofik olarak üretilebilir. Bu sebeple heterotrof sistemler, alternatif substratlar kullanarak yüksek kalitede büyük ölçekli DHA üretilmesinde uygun maliyetli bir yoldur. Yüksek hacimde heterotrofik üretim teknolojileri, kirlilik riski ve üretim maliyetini düşürmüş, ışık kısıtlaması olmaksızın yüksek oranda proses kontrolü ve yeniden üretilebilirlik sağlamıştır. Birçok durumda, heterotrof mikroalg kültürü ışık kısıtlaması ve kontrol edilebilirliği sayesinde fototrof kültüre göre daha yüksek hücre yoğunluğu ve lipid verimliliği sağlamıştır. Yüksek hacimde üretim sonuçlarına göre, başlangıç üreme hızı 0.312 h-1 olan 65g/l kuru hücre ağırlığı elde edilmiştir. Karbon azot oranı (C/N) 19.32 olarak hesaplanmıştır. Optimize edilen koşulların uygulanması sonucunda kuru hücre ağırlığının %27.5’i oranında lipid elde edilmiştir. 5 litre biyoreaktörde üretilen Schizochytrium sp. kültüründen %30.18 oranında DHA elde edilmiştir. Biyokütle, lipid ve DHA üretim verimlilikleri sırasıyla 0.65 g/l.h, 0.17g/l.h ve 0.053g/l.h olarak hesaplanmıştır. Büyük hacimde üretim tamamlandıktan sonra istenilen ürünün hücre kütlesinden belirli aşamalarla ayrılarak saflaştırılması işlemi gerçekleştirilir. Bu saflaştırma işlemleri hasat alma, su giderme, hücre parçalanması ve lipid ekstraksiyon işlemlerini içermektedir. Mikroalg kültürünün hasadı, biyokütle konsantrasyonunu arttırmak için santrifüj, filtrasyon ve çöktürme yöntemlerini içerir. Kurutma aşaması, su giderme işlemi olarak da bilinir ve hücre peletleri tamamen sudan uzaklaştırılmış olur. Lipid ekstraksiyonun verimliliğini arttırmak ve ayrıca maliyeti düşürmek için hücre peleti kurutma işlemine maruz bırakılır. Hücre parçalanması, lipid ekstraksiyonun veriminde anahtar bir rol oynamaktadır. Sonikasyon, yüksek basınçlı homojenizatörler, öğütme, enzimatik reaksiyonlar ve kimyasal hidroliz mikroalgler için yaygın olarak kullanılan hücre parçalama yöntemleridir. Mikroalg lipid ekstraksiyonu için literatürde farklı türde solvent ve ekstraksiyon yöntemleri kullanılmıştır. Genellikle hekzan, metanol, etanol ve izopropanol lipid ekstraksiyonu için kullanılan solventlerdir. Hücre parçalama ve lipid ekstraksiyon sonuçlarına göre, hekzan ile birlikte uygulanan ultrasonikasyon metodu toplam lipid oranını önemli ölçüde artırmıştır. Sonikasyon metodu uygulanarak toplam lipid oranı 1.4 kat artırılmıştır. Bununla birlikte, geleneksel lipid ekstraksiyon yöntemleri yüksek oranda toksik solvent kullanmaktadır. Süperkritik akışkan ekstraksiyonu genellikle solvent olarak yüksek basınçta karbondioksit kullanarak yüksek seçicilikle lipid ve/veya nutrasötik ürünlerin ekstraksiyonu için kullanılır. Süperkritik akışkan ekstraksiyonun süre, sıcaklık ve basıncın yağ verimi ve %DHA üzerindeki etkisi tepki yüzey metoduyla tespit edilmiştir. Süperkritik akışkan ekstraksiyonu sonuçlarına göre, basınç ve sıcaklık toplam lipid verim ve DHA konsantrasyonu üzerinde önemli etkiye sahiptir (pSchizochytrium sp. is widely studied microalgae to obtain high content of polyunsaturated fatty acids especially docosahexaenoic acid (DHA). They contain various bioactive compounds that can be used as pharmaceutical raw material, food additive, aquaculture and animal feed. They also play a crucial role in biofuel production which can be used as an alternative energy source. Schizochytrium sp. which is grown rapidly and produced high amount of DHA can be used as an alternative to fish oils. In this study, cultivation conditions were optimized to increase biomass and total lipid productivity of the Schizochytrium sp. S31 by using response surface methodology. After optimizing growth conditions, large scale production of Schizochytrium sp. S31 under favorable conditions were performed and downstream process including cell lysis, drying and lipid extraction were compared and optimized to maximize total lipid specially DHA extracted from Schizochytrium sp. S31. Finally, random mutation was applied by ultraviolet (UV) radiation or chemical mutagen and high yield of lipid accumulating mutants of a Schizochytrium sp. were selected by flow cytometric-based selection. Many factors may affect the cultivation conditions of Schizochytrium sp. such as medium composition, pH, salinity and temperature. Since polyunsaturated fatty acids have gained significance due to their role in human health, industrial and commercial usage, research on enhancement of biomass and lipid production has increased. Therefore, optimization of medium composition and environmental conditions to improve biomass and total lipid content of the organism is important. Applying a statistical strategy was an effective tool for optimization of the production and extraction process, which would also reduce the production costs through maximizing the yield. Statistical methodologies such as Plackett burman and central composite design have been extensively used to optimize several factors and their interactions. Plackett burman design was used recently as the first step in optimizing different bioprocesses to identify the factors with a significant effect on desired responses. Following the selection of the most significant factors, response surface methodology with central composite design is used to determine the optimum values of these factors. Based on contour plots and canonical analysis, a maximum biomass production of 26.86g·L-1 was obtained with 2.29 g.L-1 monosodium glutamate (MSG), pH 5.8 cultivation conditions. Maximum lipid production of 35% was obtained with 0.49 g.L- 1 MSG at 17.6 °C temperature conditions. Schizochytrium sp. S31 can be grown heterotrophically in bioreactor by supplying with alternative raw materials such as sugars, organic acids and alcohols. Thus, heterotrophic systems assure a cost effective way to obtain valuable microalgae produced DHA by using cheap substrates on large scale. Large scale heterotrophic growth technologies has lower contamination risk, lower harvesting costs, eliminated light limitation, high degree of process control and reproducible. In most instances, heterotrophic culture commonly results in much higher cell densities and lipid productivity than phototrophic culture because there is no light limitation in heterotrophic culture and controllable. According to large scale production results, 65 g/l of cell dry weight with the initial growth rate of 0.312 h-1 was obtained. C/N ratio of the Schizochytrium sp. culture was calculated as 19.32. The total lipid content was 27.5 % of the cell dry weight after applying optimized conditions. DHA percentage of the Schizochytrium sp. culture in 5 liter was calculated as 30.18%. Biomass, lipid and DHA productivity was calculated as 0.65 g/l.h, 0.17g/l.h and 0.053g/l.h respectively. Downstream processing steps required to obtain lipid from microalgal biomass once large scale production process is completed. Downstream process include harvesting, dewatering, cell disruption, lipid extraction. Harvesting microalgal culture includes centrifugation, filtration, and flocculation methods to concentrate microalgal culture. Drying step is known as post-dewatering step in which the cell pellet is completely dewatered. The cell pellet is exposed drying process for enhancing the efficiency of subsequent lipid extraction and lowering the cost of downstream process. Cell disruption is a key step in influencing lipid extraction yields. Sonication, high-pressure homogenizers, grinding, enzymatic reactions, chemical hydrolysis are the most known cell disruption methods applied for microalgae. Different types of solvents and extraction methods have been used in the literature to recover microalgal lipids. Hexane, methanol, ethanol, isopropanol are the typical solvents used for lipid extraction. According to the cell lysis and lipid extraction results, ultrasonication with hexane method increased the total lipid yield significantly with clear appearance. Sonication resulted in a 1.4-fold increase in lipid yield when compared with solvent alone. However, these traditional lipid extraction methods use large amounts of solvents that are mostly toxic. Supercritical liquid extraction (SFE) generally uses carbondioxide as a solvent at high pressure to extract lipid and/or nutraceutical products with higher selectivity in shorter extraction times. The effect of extraction temperature, pressure and time of SFE on the lipid yield and %DHA amount were investigated by using RSM. According to SFE results, pressure and temperature have significant effect (pDoktoraPh.D