Women and Social Change in Rural Tamil Nadu

One of the most significant social changes over the past 25 years in Tamil Nadu is the entry of women into the local political bodies of Gram Panchayat and Panchayat Samithi through a 33 % reservation system. Simultaneously, women are now to a large extent organised in Self-Help Groups, through which at least some of them can access loans either for small entrepreneurship or simply for smaller emergency/consumption loans. An important background to this is the increased participation of women in the non-agricultural labour market. In this article we report from a 25 year panel study of 213 agrarian households in six villages in Karur and Tiruchirapalli districts

Simulation of networks of spiking neurons: A review of tools and strategies

We review different aspects of the simulation of spiking neural networks. We start by reviewing the different types of simulation strategies and algorithms that are currently implemented. We next review the precision of those simulation strategies, in particular in cases where plasticity depends on the exact timing of the spikes. We overview different simulators and simulation environments presently available (restricted to those freely available, open source and documented). For each simulation tool, its advantages and pitfalls are reviewed, with an aim to allow the reader to identify which simulator is appropriate for a given task. Finally, we provide a series of benchmark simulations of different types of networks of spiking neurons, including Hodgkin-Huxley type, integrate-and-fire models, interacting with current-based or conductance-based synapses, using clock-driven or event-driven integration strategies. The same set of models are implemented on the different simulators, and the codes are made available. The ultimate goal of this review is to provide a resource to facilitate identifying the appropriate integration strategy and simulation tool to use for a given modeling problem related to spiking neural networks.Comment: 49 pages, 24 figures, 1 table; review article, Journal of Computational Neuroscience, in press (2007

Unbundling water and land rights in Kilifi County, Kenya: a gender perspective

Feminist scholars and activists have drawn attention to the importance of women’s land rights, and studies focused on irrigation have explored the gendered relationships between land and water rights. Yet little of this work has focused on the relationship between land and water rights for domestic and productive purposesmore broadly.Within rural communities, women andmen have dierent rights to both land and water.We explore these interconnected relationships using community profiles, focus group discussions, and in-depth interviews from two communities as well as survey data collected from multiple adult members of rural households in Kilifi County, Kenya. Using a bundle of rights framework, we find that few individuals hold the complete bundle of rights over water, and the extent to which the rights are acknowledged by others and enforceable varies by the land-water tenure system. The full bundle of rights to water ismost likely to be complete and most robust for men who have private water points on household land they hold. Even then, other people may assert claims to water at the water point, although these claims may involve negotiation or payment. Many water rights across the land-tenure systems are shared with others rather than being held by one individual. As such, the ability to negotiate water access is particularly important. The duration of the rights, or the length of time for which the rights are held, is embedded in social relations and exchange, particularly on others’ household land. Women more than men seem to maintain a complicated set of social networks that allow them to negotiate for water from other women who manage the water transactions. The process of negotiation needs to be re-articulated each time. Thus, the duration of these rights to water depends on the ongoing relationships

Assets and domestic units: methodological challenges for longitudinal studies of poverty dynamics

Tracking change in assets access and ownership in longitudinal research is difficult. Assets are rarely assigned to individuals. Their benefit and management are spread across domestic units which morph over time. We review the challenges of using assets to understand poverty dynamics, and tracking the domestic units that own and manage assets. Using case studies from longitudinal research we demonstrate that assets can afford useful insights into important change

Reconstructing the three-dimensional GABAergic microcircuit of the striatum

A system's wiring constrains its dynamics, yet modelling of neural structures often overlooks the specific networks formed by their neurons. We developed an approach for constructing anatomically realistic networks and reconstructed the GABAergic microcircuit formed by the medium spiny neurons (MSNs) and fast-spiking interneurons (FSIs) of the adult rat striatum. We grew dendrite and axon models for these neurons and extracted probabilities for the presence of these neurites as a function of distance from the soma. From these, we found the probabilities of intersection between the neurites of two neurons given their inter-somatic distance, and used these to construct three-dimensional striatal networks. The MSN dendrite models predicted that half of all dendritic spines are within 100 mu m of the soma. The constructed networks predict distributions of gap junctions between FSI dendrites, synaptic contacts between MSNs, and synaptic inputs from FSIs to MSNs that are consistent with current estimates. The models predict that to achieve this, FSIs should be at most 1% of the striatal population. They also show that the striatum is sparsely connected: FSI-MSN and MSN-MSN contacts respectively form 7% and 1.7% of all possible connections. The models predict two striking network properties: the dominant GABAergic input to a MSN arises from neurons with somas at the edge of its dendritic field; and FSIs are interconnected on two different spatial scales: locally by gap junctions and distally by synapses. We show that both properties influence striatal dynamics: the most potent inhibition of a MSN arises from a region of striatum at the edge of its dendritic field; and the combination of local gap junction and distal synaptic networks between FSIs sets a robust input-output regime for the MSN population. Our models thus intimately link striatal micro-anatomy to its dynamics, providing a biologically grounded platform for further study

Randomized comparison of gemcitabine, dexamethasone, and cisplatin versus dexamethasone, cytarabine, and cisplatin chemotherapy before autologous stem-cell transplantation for relapsed and refractory aggressive lymphomas: NCIC-CTG LY.12

PURPOSE: For patients with relapsed or refractory aggressive lymphoma, we hypothesized that gemcitabine-based therapy before autologous stem-cell transplantation (ASCT) is as effective as and less toxic than standard treatment. PATIENTS AND METHODS: We randomly assigned 619 patients with relapsed/refractory aggressive lymphoma to treatment with gemcitabine, dexamethasone, and cisplatin (GDP) or to dexamethasone, cytarabine, and cisplatin (DHAP). Patients with B-cell lymphoma also received rituximab. Responding patients proceeded to stem-cell collection and ASCT. Coprimary end points were response rate after two treatment cycles and transplantation rate. The noninferiority margin for the response rate to GDP relative to DHAP was set at 10%. Secondary end points included event-free and overall survival, treatment toxicity, and quality of life. RESULTS: For the intention-to-treat population, the response rate with GDP was 45.2%; with DHAP the response rate was 44.0% (95% CI for difference, -9.0% to 6.7%), meeting protocol-defined criteria for noninferiority of GDP (P = .005). Similar results were obtained in a per-protocol analysis. The transplantation rates were 52.1% with GDP and 49.3% with DHAP (P = .44). At a median follow-up of 53 months, no differences were detected in event-free survival (HR, 0.99; stratified log-rank P = .95) or overall survival (HR, 1.03; P = .78) between GDP and DHAP. Treatment with GDP was associated with less toxicity (P < .001) and need for hospitalization (P < .001), and preserved quality of life (P = .04). CONCLUSION: For patients with relapsed or refractory aggressive lymphoma, in comparison with DHAP, treatment with GDP is associated with a noninferior response rate, similar transplantation rate, event-free survival, and overall survival, less toxicity and hospitalization, and superior quality of life

The achievement of food and nutrition security in South Asia is deeply gendered

Women form an integral part of the agricultural sector, and in much of South Asia women make up a majority of the agricultural workforce, often compelled to work in order to meet their families’ basic needs. While their contributions are recognised as central to the food and nutrition security of households and communities, their work is not recognized or supported adequately by public policy and social institutions. Women continue to face inequality across key development indicators including health, education, and nutrition; discriminatory laws; and high levels of precarity in terms of income, employment conditions, safety and wellbeing. Social structures that promote gender inequality and inhibit the agency of women contribute to the South Asian enigma – the persistence of undernutrition despite economic growth – and must be addressed to achieve food and nutrition security

Python as a Federation Tool for GENESIS 3.0

The GENESIS simulation platform was one of the first broad-scale modeling systems in computational biology to encourage modelers to develop and share model features and components. Supported by a large developer community, it participated in innovative simulator technologies such as benchmarking, parallelization, and declarative model specification and was the first neural simulator to define bindings for the Python scripting language. An important feature of the latest version of GENESIS is that it decomposes into self-contained software components complying with the Computational Biology Initiative federated software architecture. This architecture allows separate scripting bindings to be defined for different necessary components of the simulator, e.g., the mathematical solvers and graphical user interface. Python is a scripting language that provides rich sets of freely available open source libraries. With clean dynamic object-oriented designs, they produce highly readable code and are widely employed in specialized areas of software component integration. We employ a simplified wrapper and interface generator to examine an application programming interface and make it available to a given scripting language. This allows independent software components to be ‘glued’ together and connected to external libraries and applications from user-defined Python or Perl scripts. We illustrate our approach with three examples of Python scripting. (1) Generate and run a simple single-compartment model neuron connected to a stand-alone mathematical solver. (2) Interface a mathematical solver with GENESIS 3.0 to explore a neuron morphology from either an interactive command-line or graphical user interface. (3) Apply scripting bindings to connect the GENESIS 3.0 simulator to external graphical libraries and an open source three dimensional content creation suite that supports visualization of models based on electron microscopy and their conversion to computational models. Employed in this way, the stand-alone software components of the GENESIS 3.0 simulator provide a framework for progressive federated software development in computational neuroscience