Voluntary Control of Multisaccade Gaze Shifts During Movement Preparation and Execution

Ramakrishnan A, Chokhandre S, Murthy A. Voluntary control of multisaccade gaze shifts during movement preparation and execution. J Neurophysiol 103: 2400-2416, 2010. First published February 17, 2010; doi: 10.1152/jn.00843.2009. Although the nature of gaze control regulating single saccades is relatively well documented, how such control is implemented to regulate multisaccade gaze shifts is not known. We used highly eccentric targets to elicit multisaccade gaze shifts and tested the ability of subjects to control the saccade sequence by presenting a second target on random trials. Their response allowed us to test the nature of control at many levels: before, during, and between saccades. Although the saccade sequence could be inhibited before it began, we observed clear signs of truncation of the first saccade, which confirmed that it could be inhibited in midflight as well. Using a race model that explains the control of single saccades, we estimated that it took about 100 ms to inhibit a planned saccade but took about 150 ms to inhibit a saccade during its execution. Although the time taken to inhibit was different, the high subject-wise correlation suggests a unitary inhibitory control acting at different levels in the oculomotor system. We also frequently observed responses that consisted of hypometric initial saccades, followed by secondary saccades to the initial target. Given the estimates of the inhibitory process provided by the model that also took into account the variances of the processes as well, the secondary saccades (average latency similar to 215 ms) should have been inhibited. Failure to inhibit the secondary saccade suggests that the intersaccadic interval in a multisaccade response is a ballistic stage. Collectively, these data indicate that the oculomotor system can control a response until a very late stage in its execution. However, if the response consists of multiple movements then the preparation of the second movement becomes refractory to new visual input, either because it is part of a preprogrammed sequence or as a consequence of being a corrective response to a motor error.

Photophysics of conjugated polymers: interplay between Forster energy migration and defect concentration in shaping a photochemical funnel in PPV

Recent single molecule experiments have suggested the existence of a photochemical funnel in the photophysics of conjugated polymers, like poly[2-methoxy-5-(2'-ethylhexyl)oxy-1,4-phenylenevinylene] (MEH-PPV). The funnel is believed to be a consequence of the presence of conformational or chemical defects along the polymer chain and efficient non-radiative energy transfer among different chromophore segments. Here we address the effect of the excitation energy dynamics on the photophysics of PPV. The PPV chain is modeled as a polymer with the length distribution of chromophores given either by a Gaussian or by a Poisson distribution. We observe that the Poisson distribution of the segment lengths explains the photophysics of PPV better than the Gaussian distribution. A recently proposed version of an extended particle-in-a-box' model is used to calculate the exciton energies and the transition dipole moments of the chromophores, and a master equation to describe the excitation energy transfer among different chromophores. The rate of energy transfer is assumed to be given here, as a first approximation, by the well-known Forster expression. The observed excitation population dynamics confirms the photochemical funneling of excitation energy from shorter to longer chromophores of the polymer chain. The time scale of spectral shift and energy transfer for our model polymer, with realistic values of optical parameters, is in the range of 200-300 ps. We find that the excitation energy may not always migrate towards the longest chromophore segments in the polymer chain as the efficiency of energy transfer between chromophores depends on the separation distance between the two and their relative orientation.

Ecology of the Asian Elephant in Southern India. I. Movement and Habitat Utilization Patterns

The movement and habitat utilization patterns were studied in an Asian elephant population during 1981-83 within a 1130 km2 area in southern India (110 30' N to 120 0' N and 760 50' E to 770 15' E). The study area encompasses a diversity of vegetation types from dry thorn forest (250-400 m) through deciduous forest (400-1400 m) to stunted evergreen shola forest and grassland (1400-1800 m). Home range sizes of some identified elephants were between 105 and 320 km2. Based on the dry season distribution, five different elephant clans, each consisting of between 50 and 200 individuals and having overlapping home ranges, could be defined within the study area. Seaso- nal habitat preferences were related to the availability of water and the palatability of food plants. During the dry months (January-April) elephants congregated at high densities of up to five individuals kM-2 in river valleys where browse plants had a much higher protein content than the coarse tall grasses on hill slopes. With the onset of rains of the first wet season (May- August) they dispersed over a wider area at lower densities, largely into the tall grass forests, to feed on the fresh grasses, which then had a high protein value. During the second wet season (September-December), when the tall grasses became fibrous, they moved into lower elevation short grass open forests. The normal movement pattern could be upset during years of adverse environmental con- ditions. However, the movement pattern of elephants in this region has not basically changed for over a century, as inferred from descriptions recorded during the nineteenth century.

Globalization and the Political : in the Borderlands with the Zapatista Movement

This study explores the meaning, content and significance of the political as manifest in the Mexican Zapatista movement as historically and geopolitically situated struggle. The case study undertakes a critical analysis of the development, organization, practice and discourse of the movement by drawing on fieldwork experiences, interviews, discussions, documents, films and other material produced by the movement, and the critical engagement with the research of others, especially in Latin America and Mexico. The dissertation poses the need to reconsider what constitutes and what we understand by the political , related particularly to the challenges provided by the critical globalization literature, decolonization and the study of social movements. The analysis encompasses several inter-related levels: the theoretical knowledge regarding the conceptualization of the political; the methodological level, regarding how such research can and should be conducted and knowledge claims formulated given the inescapable context and effects of global power relations; and the substantive level of adding specific information and analytical insights to existing knowledge of the Zapatista movement. As a result of conceptualization of a range of practices and processes, distinct understandings of the political can be underlined. Firstly, the conception of the indigenous and the struggles as indigenous movements as specifically political, not just a cultural or ethnic identity or a static quality but rather, an active consciousness integrally linked both to a longer history of oppression and as political articulation in the concrete context and lived experience of contemporary struggle. Secondly, the practice of autonomy as central to an understanding of the political in the context of the Zapatista struggle as a practical response to the situation of oppression, counter-insurgency, siege and conflict in Chiapas, as well as a positively informed mode of political self-understanding, expression and practice in its own right. Thirdly, the notion of geopolitical positioning as important to understanding of the political that encompasses the historicity of specific context and the power relations which shape that context, developed in two different ways: in regard to the positioning of the researcher and knowledge production with and about the Zapatistas, and in regard to the practice and knowledge of the Zapatistas as a decolonizing force in their encounters, interaction and relations with others, especially the global civil society. Finally, the role of silence, absence, invisibility, revelation and hiding in political practice as a deliberate strategy in response to oppressive power. -

Tsoi Yuen Resistance and Post-80s Generation: A new wave of domestic social movement

Hong Kong was once a British colony and has been under the sovereignty of People’s Republic of China (PRC) since 1997. However, some of the unjust practices and colonial legacies are infiltrated into the development ideology as well as the social structures. The construction of intercity express railway project announced in 2008 causing the demolishment of Tsoi Yuen Tsuen, a “non-indigenous” agricultural village in Hong Kong, was one of the current examples. Tsoi Yuen village was established under the former colonial sovereignty sixty years ago. Approximately 450 populations were affected that they had to relocate their homeland involuntarily. However, these villagers were very attached to their homelands and were unwilling to move, and meanwhile they found that they were absent in the government’s consultation and decision-making process. Soon they began their resistance and demanded for “No Move! No Demolish!”. Their movement was strongly supported by a group of “Post-80s generation” and turned into the most important social movement of the city in recent years. In fact, demolition of Tsoi Yuen Village for city development is not an isolated case in the city. Meanwhile the situation is getting worse in Mainland China. I chose the case study of Tsoi Yuen Resistance from 2008 to 2011 for revelation of the complicated colonial history and postcolonial era of Hong Kong. I focused on discussing the Tsoi Yuen Resistance and the Post-80s movement, and how they have exposed the tension between top-down urban planning and development and public movements fighting for a more democratic process in choosing their way of living. Through the study of a village movement which as well as the rationale behind the Post-80s’ support, I hoped to illustrate how this movement has awaken a different sense of living for the new generations in the midst of the high-sounding urban development. It is an opportunity to examine Hong Kong’s colonial epoch in a different perspective: through studying the Tsoi Yuen Village, let them (subalterns) speak for themselves. Furthermore, the significance of this resistance, taking place eleven years after the handover to the PRC, is an important fact that I shall not miss in later discussion. Last but not least, during the resistance, advanced technology and social networks such as Facebook, Twitter, iPhone were used by Post 80s generation to spread the latest information in order to attract public’s concern and participation. Therefore, apart from studying Tsoi Yuen Resistance as a local social movement, I also regard it as a part of the global movement in perusing ecological lifestyle and civil society. How Post 80s’ generation manipulates the global idea in a local context will also be examined.

A theory on the migration of an extraneous electron across hydrogen bonds in polypeptides

The migrating electrons in biological systems normally are extraneous and taking this into account the electron delocalisation across the hydrogen bonds in proteins is re-examined. It is seen that an extraneous electron can travel rapidly via the low-lying virtual orbitals of the hydrogen-bonded π-electronic structure of peptide units in proteins. The frequency of electron transfer decreases slowly with an increase in the path length. However, the coupling of electron and protonic motions enhances this frequency. Transfer of electrons across the hydrogen bonds in accordance with the double-exchange mechanism does not appear to be possible. This theory offers a possibility for an extraneous electron to transfer within protein structures.

Global Processes, Local Strategies : migration of educated Dominicans.

The aim of this thesis is to examine migration of educated Dominicans in light of global processes. Current global developments have resulted in increasingly global movements of people, yet people tend to come from certain places in large numbers rather than others. At the same time, international migration is increasingly selective, which shows in the disproportional number of educated migrants. This study discovers individual and societal motivations that explain why young educated Dominicans decide to migrate and return. The theoretical framework of this thesis underlines that migration is a dynamic process rooted in other global developments. Migratory movements should be seen as a result of interacting macro- and microstructures, which are linked by a number of intermediate mechanisms, meso-structures. The way individuals perceive opportunity structures concretises the way global developments mediate to the micro-level. The case of the Dominican Republic shows that there is a diversity of local responses to the world system, as Dominicans have produced their own unique historical responses to global changes. The thesis explains that Dominican migration is importantly conditioned by socioeconomic and educational background. Migration is more accessible for the educated middle class, because of the availability of better resources. Educated migrants also seem less likely to rely on networks to organize their migrations. The role of networks in migration differs by socioeconomic background on the one hand, and by the specific connections each individual has to current and previous migrants on the other hand. The personal and cultural values of the migrant are also pivotal. The central argument of this thesis is that a veritable culture of migration has evolved in the Dominican Republic. The actual economic, political and social circumstances have led many Dominicans to believe that there are better opportunities elsewhere. The globalisation of certain expectations on the one hand, and the development of the specifically Dominican feeling of ‘externalism’ on the other, have for their part given rise to the Dominican culture of migration. The study also suggests that the current Dominican development model encourages migration. Besides global structures, local structures are found to ve pivotal in determining how global processes are materialised in a specific place. The research for this thesis was conducted by using qualitative methodology. The focus of this thesis was on thematic interviews that reveal the subject’s point of view and give a fuller understanding of migration and mobility of the educated. The data was mainly collected during a field research phase in Santo Domingo, the Dominican Republic in December 2009 and January 2010. The principal material consists of ten thematic interviews held with educated Dominican current or former migrants. Four expert interviews, relevant empirical data, theoretical literature and newspaper articles were also comprehensively used.

A molecular dynamics study of cage-to-cage migration in sodium Y zeolite: role of surface-mediated diffusion

The details of cage-to-cage migration have been obtained from an analysis of the molecular dynamics trajectory of a probe adsorbate. It is observed that particles utilize the region within a radius of 2 angstrom from the window center but with diffusion taking place predominantly at 1.6 angstrom from the window center and a potential energy of nearly -12 kJ/mol. A barrier of about 0.5 kJ/mol is observed for surface-mediated diffusion. Surprisingly, for diffusion without surface mediation for a particle going from one cage center to another, there is an attractive well near the window instead of a barrier. At low adsorbate concentrations and room temperature, the predominant mode for cage-to-cage migration is surface-mediated diffusion. The analysis suggests that particles slide along the surface of the inner walls of the alpha-cages during migration from one cage to another.

Proteomic Identification of Haptoglobin alpha 2 as a Glioblastoma Serum Biomarker: Implications in Cancer Cell Migration and Tumor Growth

Glioblastoma (GBM; grade IV astrocytoma) is the most malignant and common primary brain tumor in adults. Using combination of 2-DE and MALDI-TOF MS, we analyzed 14 GBM and 6 normal control sera and identified haptoglobin alpha 2 chain as an up-regulated serum protein in GBM patients. GBM-specific up-regulation was confirmed by ELISA based quantitation of haptoglobin (Hp) in the serum of 99 GBM patients as against lower grades (49 grade III/AA; 26 grade II/DA) and 26 normal individuals (p = 0.0001). Further validation using RT-qPCR on an independent set (n = 78) of tumor and normal brain (n = 4) samples and immunohistochemcial staining on a subset (n = 42) of above samples showed increasing levels of transcript and protein with tumor grade and were highest in GBM (p = < 0.0001 and < 0.0001, respectively). Overexpression of Hp either by stable integration of Hp cDNA or exogenous addition of purified Hp to immortalized astrocytes resulted in increased cell migration. RNAi-mediated silencing of Hp in glioma cells decreased cell migration. Further, we demonstrate that both human glioma and mouse melanoma cells overexpressing Hp showed increased tumor growth. Thus, we have identified haptoglobin as a GBM-specific serum marker with a role on glioma tumor growth and migration.

Tracing water movement by means of Escherichia coli bacteriophages

Tiivistelmä: Escherichia coli bacteriofaagit merkkiaineena vesien kulkeutumistutkimuksissa

Ale jaskkot eatnigiella : Alkuperäiskansaliikkeen ja saamen kielen merkitys saamelaisten identiteetille

This study examines the Sámi people and the construction of the Sámi identity and the role of language in the cross-border Sámi movement within the context of the international indigenous movement and discourse between 1962 and 2008. The Sámi movement began as a reaction to state assimilation policies. This led to the birth of indigenous processes strengthening the Sámi cultures and languages. Activities across borders and the ethnopolitical processes in each of the Nordic countries in question also formed the basis of the internationalization of the Sámi people. The discourse on indigenous peoples has grown into a question of human rights, which is examined in different national and international contexts. The study is based on ethnographic data that has been collected via interviews, questionnaires and participant observation with the researched people in different meetings and events. Archive and newsprint material are also used. The approach of the study is auto-ethnographic. The post-colonial theories used in the study strive to destabilize power relations and the distinctions of otherness produced by colonialism, and to reclaim both one's own culture and language in the context of the indigenous movement. A standard model for this type of approach was created by Edward W. Said in his 1978 work Orientalism. The central concepts of the analysis are decolonization, otherness, ethnicity and identity. The dissertation consists of four published articles and an introduction. The subject matter is analyzed on three levels: global, European and Nordic. On the global level, the results demonstrate that the indigenous movement has constructed a new understanding of indigenousness with new rights. International treaties have facilitated the unification of new concepts and rights, such as the right to self-determination and language, also helping in transforming them into rights of the Sámi people on a national level. On the Nordic level, aligning the Sámi culture with indigenous discourse became significant for the process of developing the Sámi identity in the Sámi movement. In this process, the Sámi movement made use of Sámi languages in order to mobilize groups of people and to construct relatedness between different Sámi groups. The realization that one s own language is significant to one's culture has resulted in recreating the vitality, visibility and the legitimation of language in society more generally. The migration of the Sámi people from their traditional territories to increasingly multi-ethnic urban areas alters one's relationship to one's own community as the relationship to cultural traditions changes. Among the urban Sámi, who form a group of ‘new Sáminess’, linguistic discrimination and assimilation continue because of the lack of legislative and other effective language policy measures to promote the learning and use of the Sámi language.

Interaction of Sesbania mosaic virus movement protein with the coat protein - implications for viral spread

Sesbania mosaic virus (SeMV) is a single-stranded positive-sense RNA plant virus belonging to the genus Sobemovirus. The movement protein (MP) encoded by SeMV ORF1 showed no significant sequence similarity with MPs of other genera, but showed 32% identity with the MP of Southern bean mosaic virus within the Sobemovirus genus. With a view to understanding the mechanism of cell-to-cell movement in sobemoviruses, the SeMV MP gene was cloned, over-expressed in Escherichia coli and purified. Interaction of the recombinant MP with the native virus (NV) was investigated by ELISA and pull-down assays. It was observed that SeMV MP interacted with NV in a concentration- and pH-dependent manner. Analysis of N- and C-terminal deletion mutants of the MP showed that SeMV MP interacts with the NV through the N- terminal 49 amino acid segment. Yeast two-hybrid assays confirmed the in vitro observations, and suggested that SeMV might belong to the class of viruses that require MP and NV/coat protein for cell-to-cell movement.

Migration-Development Nexus in the Malawian Health Sector: European Union Blue Card – circular migration for development?

The European Union has agreed on implementing the Policy Coherence for Development (PCD) principle in all policy sectors that are likely to have a direct impact on developing countries. This is in order to take account of and support the EU development cooperation objectives and the achievement of the internationally agreed Millennium Development Goals. The common EU migration policy and the newly introduced EU Blue Card directive present an example of the implementation of the principle in practice: the directive is not only designed to respond to the occurring EU labour demand by attracting highly skilled third-country professionals, but is also intended to contribute to the development objectives of the migrant-sending developing countries, primarily through the tool of circular migration and the consequent skills transfers. My objective in this study is to assess such twofold role of the EU Blue Card and to explore the idea that migration could be harnessed for the benefit of development in conformity with the notion that the two form a positive nexus. Seeing that the EU Blue Card fails to differentiate the most vulnerable countries and sectors from those that are in a better position to take advantage of the global migration flows, the developmental consequences of the directive must be accounted for even in the most severe settings. Accordingly, my intention is to question whether circular migration, as claimed, could address the problem of brain drain in the Malawian health sector, which has witnessed an excessive outflow of its professionals to the UK during the past decade. In order to assess the applicability, likelihood and relevance of circular migration and consequent skills transfers for development in the Malawian context, a field study of a total of 23 interviews with local health professionals was carried out in autumn 2010. The selected approach not only allows me to introduce a developing country perspective to the on-going discussion at the EU level, but also enables me to assess the development dimension of the EU Blue Card and the intended PCD principle through a local lens. Thus these interviews and local viewpoints are at the very heart of this study. Based on my findings from the field, the propensity of the EU Blue Card to result in circular migration and to address the persisting South-North migratory flows as well as the relevance of skills transfers can be called to question. This is as due to the bias in its twofold role the directive overlooks the importance of the sending country circumstances, which are known to determine any developmental outcomes of migration, and assumes that circular migration alone could bring about immediate benefits. Without initial emphasis on local conditions, however, positive outcomes for vulnerable countries such as Malawi are ever more distant. Indeed it seems as if the EU internal interests in migration policy forbid the fulfilment of the PCD principle and diminish the attempt to harness migration for development to bare rhetoric.