Translational fusion of two beta-subunits of human chorionic gonadotropin results in production of a novel antagonist of

The strategy of translationally fusing the alpha-and beta-subunits of human chorionic gonadotropin (hCG) into a single-chain molecule has been used to produce novel analogs of hCG. Previously we reported expression of a biologically active singlechain analog hCG alpha beta expressed using Pichia expression system. Using the same expression system, another analog, in which the alpha-subunit was replaced with the second beta-subunit, was expressed (hCG beta beta) and purified. hCG beta beta could bind to LH receptor with an affinity three times lower than that of hCG but failed to elicit any response. However, it could inhibit response to the hormone in vitro in a dose- dependent manner. Furthermore, it inhibited response to hCG in vivo indicating the antagonistic nature of the analog. However, it was unable inhibit human FSH binding or response to human FSH, indicating the specificity of the effect. Characterization of hCG alpha beta and hCG beta beta using immunological tools showed alterations in the conformation of some of the epitopes, whereas others were unaltered. Unlike hCG, hCG beta beta interacts with two LH receptor molecules. These studies demonstrate that the presence of the second beta-subunit in the single-chain molecule generated a structure that can be recognized by the receptor. However, due to the absence of alpha-subunit, the molecule is unable to elicit response. The strategy of fusing two beta-subunits of glycoprotein hormones can be used to produce antagonists of these hormones.

Non-Gaussianities and Preheating from N-flation and Magnetogenesis via rotating cosmic string loops

In this thesis we examine multi-field inflationary models of the early Universe. Since non-Gaussianities may allow for the possibility to discriminate between models of inflation, we compute deviations from a Gaussian spectrum of primordial perturbations by extending the delta-N formalism. We use N-flation as a concrete model; our findings show that these models are generically indistinguishable as long as the slow roll approximation is still valid. Besides computing non-Guassinities, we also investigate Preheating after multi-field inflation. Within the framework of N-flation, we find that preheating via parametric resonance is suppressed, an indication that it is the old theory of preheating that is applicable. In addition to studying non-Gaussianities and preheatng in multi-field inflationary models, we study magnetogenesis in the early universe. To this aim, we propose a mechanism to generate primordial magnetic fields via rotating cosmic string loops. Magnetic fields in the micro-Gauss range have been observed in galaxies and clusters, but their origin has remained elusive. We consider a network of strings and find that rotating cosmic string loops, which are continuously produced in such networks, are viable candidates for magnetogenesis with relevant strength and length scales, provided we use a high string tension and an efficient dynamo.

Multiscale study on hydrogen mobility in metallic fusion divertor material

For achieving efficient fusion energy production, the plasma-facing wall materials of the fusion reactor should ensure long time operation. In the next step fusion device, ITER, the first wall region facing the highest heat and particle load, i.e. the divertor area, will mainly consist of tiles based on tungsten. During the reactor operation, the tungsten material is slowly but inevitably saturated with tritium. Tritium is the relatively short-lived hydrogen isotope used in the fusion reaction. The amount of tritium retained in the wall materials should be minimized and its recycling back to the plasma must be unrestrained, otherwise it cannot be used for fueling the plasma. A very expensive and thus economically not viable solution is to replace the first walls quite often. A better solution is to heat the walls to temperatures where tritium is released. Unfortunately, the exact mechanisms of hydrogen release in tungsten are not known. In this thesis both experimental and computational methods have been used for studying the release and retention of hydrogen in tungsten. The experimental work consists of hydrogen implantations into pure polycrystalline tungsten, the determination of the hydrogen concentrations using ion beam analyses (IBA) and monitoring the out-diffused hydrogen gas with thermodesorption spectrometry (TDS) as the tungsten samples are heated at elevated temperatures. Combining IBA methods with TDS, the retained amount of hydrogen is obtained as well as the temperatures needed for the hydrogen release. With computational methods the hydrogen-defect interactions and implantation-induced irradiation damage can be examined at the atomic level. The method of multiscale modelling combines the results obtained from computational methodologies applicable at different length and time scales. Electron density functional theory calculations were used for determining the energetics of the elementary processes of hydrogen in tungsten, such as diffusivity and trapping to vacancies and surfaces. Results from the energetics of pure tungsten defects were used in the development of an classical bond-order potential for describing the tungsten defects to be used in molecular dynamics simulations. The developed potential was utilized in determination of the defect clustering and annihilation properties. These results were further employed in binary collision and rate theory calculations to determine the evolution of large defect clusters that trap hydrogen in the course of implantation. The computational results for the defect and trapped hydrogen concentrations were successfully compared with the experimental results. With the aforedescribed multiscale analysis the experimental results within this thesis and found in the literature were explained both quantitatively and qualitatively.

Computer simulation of H and He effects in fusion reactor materials

Fusion power is an appealing source of clean and abundant energy. The radiation resistance of reactor materials is one of the greatest obstacles on the path towards commercial fusion power. These materials are subject to a harsh radiation environment, and cannot fail mechanically or contaminate the fusion plasma. Moreover, for a power plant to be economically viable, the reactor materials must withstand long operation times, with little maintenance. The fusion reactor materials will contain hydrogen and helium, due to deposition from the plasma and nuclear reactions because of energetic neutron irradiation. The first wall divertor materials, carbon and tungsten in existing and planned test reactors, will be subject to intense bombardment of low energy deuterium and helium, which erodes and modifies the surface. All reactor materials, including the structural steel, will suffer irradiation of high energy neutrons, causing displacement cascade damage. Molecular dynamics simulation is a valuable tool for studying irradiation phenomena, such as surface bombardment and the onset of primary damage due to displacement cascades. The governing mechanisms are on the atomic level, and hence not easily studied experimentally. In order to model materials, interatomic potentials are needed to describe the interaction between the atoms. In this thesis, new interatomic potentials were developed for the tungsten-carbon-hydrogen system and for iron-helium and chromium-helium. Thus, the study of previously inaccessible systems was made possible, in particular the effect of H and He on radiation damage. The potentials were based on experimental and ab initio data from the literature, as well as density-functional theory calculations performed in this work. As a model for ferritic steel, iron-chromium with 10% Cr was studied. The difference between Fe and FeCr was shown to be negligible for threshold displacement energies. The properties of small He and He-vacancy clusters in Fe and FeCr were also investigated. The clusters were found to be more mobile and dissociate more rapidly than previously assumed, and the effect of Cr was small. The primary damage formed by displacement cascades was found to be heavily influenced by the presence of He, both in FeCr and W. Many important issues with fusion reactor materials remain poorly understood, and will require a huge effort by the international community. The development of potential models for new materials and the simulations performed in this thesis reveal many interesting features, but also serve as a platform for further studies.

Micro-treatment options for components of organic fraction of MSW in residential areas

There is a growing interest in management of MSW through micro-treatment of organic fraction of municipal solid wastes (OFMSW) in many cities of India. The OFMSW fraction is high (> 80%) in many pockets within South Indian cities like Bangalore, Chikkamagalur, etc. and is largely represented by vegetable, fruit, packing and garden wastes. Among these, the last three have shown problems for easy decomposition. Fruit wastes are characterized by a large pectin supported fraction that decomposes quickly to organic acids (becomes pulpy) that eventually slow down anaerobic and aerobic decomposition processes. Paper fraction (newsprint and photocopying paper) as well as paddy straw (packing), bagasse (from cane juice stalls) and tree leaf litter (typical garden waste and street sweepings) are found in reasonably large proportions in MSW. These decompose slowly due to poor nutrients or physical state. We have examined the suitability of these substrates for micro-composting in plastic bins by tracking decomposition pattern and physical changes. It was found that fruit wastes decompose rapidly to produce organic acids and large leachate fraction such that it may need to be mixed with leachate absorbing materials (dry wastes) for good composting. Leaf litter, paddy straw and bagasse decompose to the tune of 90, 68 and 60% VS and are suitable for composting micro-treatment. Paper fractions even when augmented with 10% leaf compost failed to show appreciable decomposition in 50 days. All these feedstocks were found to have good biological methane potential (BMP) and showed promise for conversion to biogas under a mixed feed operation. Suitability of this approach was verified by operating a plug-flow type anaerobic digester where only leaf litter gathered nearby (as street sweepings) was used as feedstock. Here only a third of the BMP was realized at this scale (0.18 m(3) biogas/kg VS 0.55 m(3)/kg in BMP). We conclude that anaerobic digestion in plug-flow like digesters appear a more suitable micro-treatment option (2-10 kg VS/day) because in addition to compost it also produces biogas for domestic use nearby.

Efficient content-based image retrieval based on multi-feature fusion

The increased availability of image capturing devices has enabled collections of digital images to rapidly expand in both size and diversity. This has created a constantly growing need for efficient and effective image browsing, searching, and retrieval tools. Pseudo-relevance feedback (PRF) has proven to be an effective mechanism for improving retrieval accuracy. An original, simple yet effective rank-based PRF mechanism (RB-PRF) that takes into account the initial rank order of each image to improve retrieval accuracy is proposed. This RB-PRF mechanism innovates by making use of binary image signatures to improve retrieval precision by promoting images similar to highly ranked images and demoting images similar to lower ranked images. Empirical evaluations based on standard benchmarks, namely Wang, Oliva & Torralba, and Corel datasets demonstrate the effectiveness of the proposed RB-PRF mechanism in image retrieval.

Pengarna eller livet? : En kvalitativ och longitudinell studie om långtidsarbetslösa unga i ett aktörsperspektiv

Your money or your life? A qualitative follow-up study of the young unemployed from an actor perspective is a qualitative and longitudinal study following 36 unemployed young people in Helsinki over a span of ten years. The purpose of the study is to shed light on how a few young people view employment/unemployment and their lives and future, how they as unemployed perceive their encounters with society, and how society supports them. Four so-called key informants were followed at a finer level of empirical detail. They were chosen for the thematic interviews because of their different personalities, starting points and preferences. Although some differences were expected, what the results show is quite striking. The individual stories raise a number of questions about differences between young people, about society s view of the young unemployed, and about the principles behind the so-called activation policy and how society s support is distributed. The key informants descriptions underline that the group young unemployed does not consist of individuals who are alike but that life is complex, that paid work and unemployment can be perceived very differently, and that background and unofficial support can have consequences for self-perception and for ways of looking at the future, vocational choices, paid work and activation policy. Margaret S. Archer s theory of Morphogenesis and Barbara Cruikshank s theory of constructing democracies compose the study s theoretical framework. The key informants stories give a picture of a formal support system that, even though it puts part of the responsibility for unemployment on the individuals themselves, in the name of fairness and equality, treats them in an impersonal way, not giving their personal situation and wishes much weight. As a consequence, those who share the dominant values of society do well, while others who do not are faced with difficulties. The bigger the gap between society s and the individual s values, the bigger the risk to be met by little understanding and by penalties. And vice versa: Those who initially have the right values and know how to deal with authorities get heard and their opinions get accepted. The informants ask for a more personal encounter, which could improve both the atmosphere and the clients experiences of being heard. Still the risk of having a more individualistic system should be addressed, as a new system might generate new winners, but just as well give new losers. Finally, we have to ask if the so-called activation policy is looking for answers primarily to a macro-level problem on the micro-level. If it does not produce more jobs, its support for the unemployed will be insignificant. It is not enough to think about what to do at the grassroots level to make the system more functional and support job-seeking. If the current rate of unemployment endures, the quality of life of the unemployed should be addressed. A first step could be taken by placing less guilt on the unemployed. Instead of talking about activating the unemployed, discussion should be targeted at removing structural impediments to employment. If we want to have less polarisation between the those with paid work and those without, who often struggle with low incomes, we need to include the macro-level in the discussion. What does high unemployment mean in a work-based society, where the individual s self-perception and important social forms of support are linked to labour income? And what can be done at the macro-level to change this undesirable condition at the micro-level? Keywords: Unemployment, Youth, Public interventions, Activation policy, Individual actors, Qualitative, Longitudinal, Holistic, Helsinki, Finland

Robust flight stability and control for micro air vehicles.

This chapter presents the real time validation of fixed order robust 112 controller designed for the lateral stabilisation of a micro air vehicle named Sarika2. Digital signal processor (DSP) based onboard computer named flight instrumentation controller (FIC) is designed to operate under automatic or manual mode. FIC gathers data from multitude of sensors and is capable of closed loop control to enable autonomous flight. Fixed order lateral H-2 controller designed with the features such as incorporation of level I flying qualities, gust alleviation and noise rejection is coded on to the FIC. Challenging real time hardware in loop simulation (HILS) is done with dSPACE1104 RTI/RTW. Responses obtained from the HILS are compared with those obtained from the offline simulation. Finally, flight trials are conducted to demonstrate the satisfactory performance of the closed loop system. The generic design methodology developed is applicable to all classes of Mini and Micro air vehicles.

Selection of intrusion detection system threshold bounds for effective sensor fusion

The motivation behind the fusion of Intrusion Detection Systems was the realization that with the increasing traffic and increasing complexity of attacks, none of the present day stand-alone Intrusion Detection Systems can meet the high demand for a very high detection rate and an extremely low false positive rate. Multi-sensor fusion can be used to meet these requirements by a refinement of the combined response of different Intrusion Detection Systems. In this paper, we show the design technique of sensor fusion to best utilize the useful response from multiple sensors by an appropriate adjustment of the fusion threshold. The threshold is generally chosen according to the past experiences or by an expert system. In this paper, we show that the choice of the threshold bounds according to the Chebyshev inequality principle performs better. This approach also helps to solve the problem of scalability and has the advantage of failsafe capability. This paper theoretically models the fusion of Intrusion Detection Systems for the purpose of proving the improvement in performance, supplemented with the empirical evaluation. The combination of complementary sensors is shown to detect more attacks than the individual components. Since the individual sensors chosen detect sufficiently different attacks, their result can be merged for improved performance. The combination is done in different ways like (i) taking all the alarms from each system and avoiding duplications, (ii) taking alarms from each system by fixing threshold bounds, and (iii) rule-based fusion with a priori knowledge of the individual sensor performance. A number of evaluation metrics are used, and the results indicate that there is an overall enhancement in the performance of the combined detector using sensor fusion incorporating the threshold bounds and significantly better performance using simple rule-based fusion.

Urban growth dilemmas and solutions in China: Looking forward to 2030

China’s urbanization and industrialization are occupying farmland in large amounts, which is strongly driven by land finance regime. This is due to the intensified regional/local competition for manufacturing investment opportunities that push local governments to expropriate farmland at low prices while lease land at high market value to property developers. The additional revenue obtained in this way, termed financial increment in land values, can drive local economic growth, and provide associated infrastructure and other public services. At the same time, however, a floating population of large numbers of inadequately compensated land-lost farmers, although unable to become citizens, have to migrate into the urban areas for work, causing overheated employment and housing markets, with rocketing unaffordable housing prices. This, together with various micro factors relating to the party/state’s promotion/evaluation system play an essential role leading to some serious economic, environment and social consequences, e.g., on migrant welfare, the displacement of peasants and the loss of land resources that requires immediate attention. Our question is: whether such type of urbanization is sustainable? What are the mechanisms behind such a phenomenal urbanization process? From the perspective of institutionalism, this paper aims to investigate the institutional background of the urban growth dilemma and solutions in urban China and to introduce further an inter-regional game theoretical framework to indicate why the present urbanization pattern is unsustainable. Looking forward to 2030, paradigm policy changes are made from the triple consideration of floating population, social security and urban environmental pressures. This involves: (1) changing land increment based finance regime into land stock finance system; (2) the citizenization of migrant workers with affordable housing, and; (3) creating a more enlightened local government officer appraisal system to better take into account societal issues such as welfare and beyond.

Growing Flowers in the Frost: Civic Activity, Citizenship and Gender in Russia

This study analyzes civic activity, citizenship and their gendered manifestations in contemporary Russia. It is based on a case study conducted in the city of Tver , located in the vicinity of Moscow, during 2001-2005. The data consists of interviews with civic activists and municipal and regional authorities; observations of civic organizations; and a quantitative survey conducted among local civic groups. The theoretical and methodological framework of the study draws upon a micro perspective on organization, discourse analysis, gender and citizenship theories and Pierre Bourdieu s theory of fields and capital. This study develops theoretical understanding of the characteristics and logic of civic organization in Russia. It shows that social class centrally structures the field of civic activity. Organizations can be seen as a vehicle of the educated class to advocate their interests, help themselves and seek both social and individual-level change. The study also argues that civic organizations founded during the post-Soviet era are often an institutionalized form of informal social networks. Networks, which were a central element of everyday interaction in Soviet society, are a resource and often the only resource available that can be made use of in contemporary organizational activities. The study argues that gender operates as a key structuring principle in the Russian socio-political community. Civic activity is often discursively associated with femininity and institutional politics with masculinity. Women tend to participate more than men in civic organizations, while men dominate the formal political domain. The study shows that civic organizations are important loci of communality. This communality, however, differs from the communality envisioned in the communitarian and social capital debates in the West. It is selective communality , as it is restricted to the members of the organizations and does not create generalized reciprocity and trust. Civic organizations tend to build upon and reproduce the traditional Russian organizational form of circles , kruzhki. Along with the analysis of civic activities, the study also examines the redefinition of the role and functions of the state. The authorities interviewed in this study understand civic organizations as serving those goals and interests determined by the authorities, instead of viewing them as sites of citizens self-organization around interests and problems citizens themselves deem important, or as a counterforce to the state. By contrast, civic activists understand the core of organizational activity to be advocacy of their interests and rights, tackling social problems, the pursuit of wider social change and self-help. Co-operation between authorities and organizations tends to be personified and based upon unequal, hierarchical patron-client arrangements, which inhibits the development of democratic governance. The study will be published in Routledge Contemporary Russia and Eastern Europe Series later this year.

Interrelations of micro-organisms and mulberry III. The beneficial influence of certain heterotrophs on the nitrifiers in rhizosphere

Evidence has been presented to show that the autotrophic nitrifying organisms get stimulated in the mulberry rhizosphere. Three species of Pseudomonas, one each of Achromobacter and Bacillus capable of degrading methionine were shown to be stimulated in the rhizosphere. These bacteria were capable of reversing the inhibitory effect of methionine on soil nitrification. Two of them were able to form nitrite from methionine. The possibility that the increased nitrifying activity in the mulberry rhizosphere in the presence of methionine found in mulberry root exudations was the result of the activity of these organisms was suggested.

Interrelations of micro-organisms and mulberry II. Phyllosphere microflora and nitrogen fixation in leaf and root surfaces

The mulberry leaves were shown to harbour substantial populations of bacteria, streptomycetes, yeasts, and moulds. Azotobacter and Beijerinckia were observed to contribute to nearly 5 to 10 per cent of the bacterial population. When grown in water culture under sterile conditions, Azotobacter inoculation on the leaf or root surface was found to increase plant growth, dry wt, and nitrogen content of the mulberry. The beneficial effect of Azotobacter was largely influenced by the presence of a carbon source in the plant nutrient solution. The root inoculation in comparison to leaf application was found to confer greater benefits to the growing plant. The presence of carbohydrates and amino acids in the leaf leachates of mulberry was shown. The mutual beneficial nature of the association of the plant and Azotobacter has been brought to light.

Interrelations of soil micro-orgamisms and mulberry I.Phytohormone production by soil and rhizosphere bacteria and their effect on plant growth

Bacteria isolated from the rhizosphere of mulberry (Morus indica) as well as from control soil were tested for their effects on the growth of mulberry seedlings and for phytohormone production. About 12.8 per cent of the rhizosphere and 9.7 per cent of the soil isolates produced phytohormones in cultures. Rhizosphere isolates were more active in hormone synthesis than their soil counterparts. Soaking mulberry stem cuttings in culture filtrates of phytohormone synthesisers hastened their rooting. Culture filtrates of many isolates — hormone producers or not — stimulated or inhibited the growth of shoot and/or root of plants. Many cultures could also inhibit the germination of mulberry seeds.