Policing Urban Violence: Lessons from South Asia

As densely populated urban centres emerge as economic powerhouses where global GDP is concentrated, they are also increasingly vulnerable to shocks of violence and insecurity. Well-managed urban economies have the potential to provide a route out of poverty, however, poor urban communities are disproportionately affected by violence, making the provision of effective and sustainable security in urban centres a key issue in developing countries. IDS research in South Asia shows that urban insecurity tends to receive an overtly militaristic response. While urban police forces continue to play a central role in creating safe and secure urban environments, it is also evident however, that sustainable security results from wider collaborations between state and non-state actors.UK Department for International Developmen

Spatiotemporal intermittency and scaling laws in the coupled sine circle map lattice

We study spatio-temporal intermittency (STI) in a system of coupled sine circle maps. The phase diagram of the system shows parameter regimes with STI of both the directed percolation (DP) and non-DP class. STI with synchronized laminar behaviour belongs to the DP class. The regimes of non-DP behaviour show spatial intermittency (SI), where the temporal behaviour of both the laminar and burst regions is regular, and the distribution of laminar lengths scales as a power law. The regular temporal behaviour for the bursts seen in these regimes of spatial intermittency can be periodic or quasi-periodic, but the laminar length distributions scale with the same power-law, which is distinct from the DP case. STI with traveling wave (TW) laminar states also appears in the phase diagram. Soliton-like structures appear in this regime. These are responsible for cross-overs with accompanying non-universal exponents. The soliton lifetime distributions show power law scaling in regimes of long average soliton life-times, but peak at characteristic scales with a power-law tail in regimes of short average soliton life-times. The signatures of each type of intermittent behaviour can be found in the dynamical characterisers of the system viz. the eigenvalues of the stability matrix. We discuss the implications of our results for behaviour seen in other systems which exhibit spatio-temporal intermittency.Comment: 25 pages, 11 figures. Submitted to Phys. Rev.

Vehicles Recognition Using Fuzzy Descriptors of Image Segments

In this paper a vision-based vehicles recognition method is presented. Proposed method uses fuzzy description of image segments for automatic recognition of vehicles recorded in image data. The description takes into account selected geometrical properties and shape coefficients determined for segments of reference image (vehicle model). The proposed method was implemented using reasoning system with fuzzy rules. A vehicles recognition algorithm was developed based on the fuzzy rules describing shape and arrangement of the image segments that correspond to visible parts of a vehicle. An extension of the algorithm with set of fuzzy rules defined for different reference images (and various vehicle shapes) enables vehicles classification in traffic scenes. The devised method is suitable for application in video sensors for road traffic control and surveillance systems.Comment: The final publication is available at http://www.springerlink.co

Transport and diffusion in the embedding map

We study the transport properties of passive inertial particles in a $2-d$ incompressible flows. Here the particle dynamics is represented by the $4-d$ dissipative embedding map of $2-d$ area-preserving standard map which models the incompressible flow. The system is a model for impurity dynamics in a fluid and is characterized by two parameters, the inertia parameter $\alpha$, and the dissipation parameter $\gamma$. We obtain the statistical characterisers of transport for this system in these dynamical regimes. These are, the recurrence time statistics, the diffusion constant, and the distribution of jump lengths. The recurrence time distribution shows a power law tail in the dynamical regimes where there is preferential concentration of particles in sticky regions of the phase space, and an exponential decay in mixing regimes. The diffusion constant shows behaviour of three types - normal, subdiffusive and superdiffusive, depending on the parameter regimes. Phase diagrams of the system are constructed to differentiate different types of diffusion behaviour, as well as the behaviour of the absolute drift. We correlate the dynamical regimes seen for the system at different parameter values with the transport properties observed at these regimes, and in the behaviour of the transients. This system also shows the existence of a crisis and unstable dimension variability at certain parameter values. The signature of the unstable dimension variability is seen in the statistical characterisers of transport. We discuss the implications of our results for realistic systems.Comment: 28 pages, 14 figures, To Appear in Phys. Rev. E; Vol. 79 (2009

Scaffold Pore Size and Calcium Phosphate Coating Control Chondrogenesis and Endochondral Ossification.

In the United States, 30% of adults suffer joint pain, most commonly in the knee. Knee pain can severely limit mobility and can often be contributed to injury to the cartilage and underlying bone in the joint. Unfortunately, a growing population of young athletes is developing osteochondral knee injuries due to repetitive joint stress and sports-related injuries such as meniscus or ligament tears. Microfracture and autografts are currently primary treatments for small osteochondral defects. However, microfracture results in less resilient fibrocartilage with eventual failure, and autografting can cause donor site morbidity and poor integration. To overcome these significant drawbacks, material scientists and bioengineers have collaborated to design tissue-engineered cartilage-bone grafts as an alternate therapy for small osteochondral defects. Recently, we made significant progress in developing novel nanofibrous, porous polymer scaffolds with a highly uniform, spherical, well-interconnected porous network for tissue regeneration. The goal of this project was to optimize scaffold pore architecture of a polymer/ceramic composite scaffold for both cartilage and bone regeneration. Using a 3D nanofibrous poly(ʟ-lactic acid) (PLLA) scaffold seeded with bone marrow-derived mesenchymal stem cells (BMSCs), the following three specific aims were investigated. Aim 1 determined the effect of scaffold pore size on chondrogenic differentiation and cartilage formation both in vitro and in vivo. Aim 2 optimized scaffold pore size in an ectopic model to control endochondral ossification for bone regeneration. Aim 3 evaluated the effect of electrodeposited calcium phosphate on the porous scaffold on bone formation. In this dissertation, we revealed that chondrogenesis and endochondral ossification can be controlled by scaffold pore architecture and enhanced by a calcium phosphate coating to direct cartilage and bone regeneration. In the future, the tissue-engineered cartilage and bone graft materials could be combined into a biphasic scaffold for an osteochondral knee graft with two unique pore sizes and biphasic growth factor delivery, as shown by preliminary data. This cell-instructive, biomimetic composite material could even serve as a platform to engineer various complex tissues and organ systems.PhDBiomedical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111634/1/mgupte_1.pd

Paucity of Public Funds and Growth of Professional Colleges in India

Indian higher education has undergone a metamorphosis in the last several years The right to education is a fundamental right in India Education falls under the Concurrent list of the Indian Constitution In 1997 the Indian Government in its proposals for subsidies accorded higher education the status of a non - merit good while elementary education remained a merit good The Ministry of Finance Government of India thus reclassified higher education as a merit-2-good which need not be subsidized by the state as a merit good One of the major hurdles confronting our system is that of scarcity of finance Beginning with the Kothari Commission all the succeeding Committees have emphasized the need for increasing the budgetary allocation for higher education However in the light of increasing demand and competitiveness more specifically after 1991 public funding is becoming difficult and this has led to growing privatization in the education sector The spurt in Privatization is more clearly reflected in the Professional sector where India has witnessed the growth of Professional Colleges namely engineering medicine and management They have their own merits and demerits While India boasts of a few high quality institutions some are very backward They have to be regulated if India has to make her mark as a knowledge hub in the near futur

Connectivity strategies to enhance the capacity of weight-bearing networks

The connectivity properties of a weight-bearing network are exploited to enhance it's capacity. We study a 2-d network of sites where the weight-bearing capacity of a given site depends on the capacities of the sites connected to it in the layers above. The network consists of clusters viz. a set of sites connected with each other with the largest such collection of sites being denoted as the maximal cluster. New connections are made between sites in successive layers using two distinct strategies. The key element of our strategies consists of adding as many disjoint clusters as possible to the sites on the trunk $T$ of the maximal cluster. The new networks can bear much higher weights than the original networks and have much lower failure rates. The first strategy leads to a greater enhancement of stability whereas the second leads to a greater enhancement of capacity compared to the original networks. The original network used here is a typical example of the branching hierarchical class. However the application of strategies similar to ours can yield useful results in other types of networks as well.Comment: 17 pages, 3 EPS files, 5 PS files, Phys. Rev. E (to appear

Details matter when modelling the effects of animal personality on the spatial distribution of foragers

By means of a simulation study, DiNuzzo & Griffen [1] investigate whether individual variation in a personality trait can explain ‘undermatching’, an often-observed deviation from the ideal free distribution (IFD). Here, we raise five points of concern about this study, regarding (i) the interpretation of the results in terms of personality variation; (ii) deficiencies in the technical implementation of the model, leading to wrong conclusions; (iii) the effects of population size on deviations from the IFD; (iv) the measure used for quantifying deviations from the IFD and (v) the analysis of the mud crab data. Finally, we provide an overview of the evolutionary ramifications of the relation between animal personality and the IFD