(WP 2013-03) War and the Fiscal Capacity of the State

We examine the role of war in retarding state fiscal capacity in developing countries, measured by tax revenue ratios to GDP. This in contrast to the European experience from the Renaissance to the 20th century, where it is believed that war and state-building were inseparable, enhancing the fiscal capacity of the state; in turn enlarging the scope and magnitude of government expenditure. We build a simple theoretical model of a factionalized state, where patronage substitutes for common interest public goods, along with the possibility of violent contestation over a rent or prize, typically in the form of natural resource revenues. Our dynamic panel empirical analysis on the determinants of fiscal capacity is applied to 79 developing countries, during 1980-2010. Results indicate that war, especially in its current dominant form of civil war, retards fiscal capacity, along with imperfect democracy, political repression, the quality of governance, dependence on oil and macroeconomic mismanagement. High intensity conflict is particularly destructive of state capacity. Countries experiencing low intensity wars, other institutional factors may matter more for fiscal capacity formation compared to war. The diminution of state capacity due to war appears less pronounced after the end of the cold war

A Note on War and Fiscal Capacity in Developing Countries

We examine the effect of war on state fiscal capacity in developing countries, measured by tax revenue to GDP ratios. In divided or factionalised societies, patronage may substitute for common interest public goods, with the possibility of violent contestation over a rent. Our dynamic panel empirical estimates of the determinants of fiscal capacity are applied to 79 developing countries, during 1980–2010. Results indicate that war, especially civil war, retards fiscal capacity, along with poor governance, oil dependence and macroeconomic mismanagement

A low bit-rate video-coding algorithm based upon variable pattern selection

Recent research into pattern representation of moving regions in blocked-based motion estimation and compensation in video sequences, has focused mainly upon using a fixed number of regular shaped patterns. These are used to match the macroblocks in a frame that have two distinct regions involving static background and moving objects. In this paper a new Variable Pattern Selection (VPS) algorithm is presented which selects a preset number of best-matched patterns from a pattern codebook of regular shaped patterns. While more patterns are used than in the previous work, the performance of the VPS algorithm in using variable length coding, by exploiting the frequency of the best-matched patterns, leads to a higher compression ratio, without degrading the overall image quality

By How Much Does Conflict Reduce Financial Development?

Financial development is vulnerable to social conflict. Conflict reduces the demand for domestic currency as a medium of exchange and a store of value. Conflict also leads to poor quality governance, including weak regulation of the financial system, thereby undermining the sustainability of financial institutions. Conflict therefore reduces the social return to financial liberalization and other financial-sector reforms. This paper presents a theoretical model integrating the effects of conflict and financial liberalization, and then tests the model on data for 79 countries. Using an explanatory variable that measures the intensity of conflict (from low to high) the results show that conflict significantly reduces financial development, and that this negative effect increases as conflict intensifies. The paper concludes that conflict reduction is essential if financial reform is to have its full benefit for development

A novel filter for block-based motion estimation

Noises, in the form of false motion vectors, cannot be avoided while capturing block motion vectors using block based motion estimation techniques. Similar noises are further introduced when the technique of global motion compensation is applied to obtain 'true' object motion from video sequences, where both the camera and object motions are present. We observe that the performance of the mean and the median filters in removing false motion vectors, for estimating 'true' object motion, is not satisfactory, especially when the size of the object is significantly smaller than the scene. In this paper we introduce a novel filter, named as the Mean-Accumulated-Thresholded (MAT) filter, in order to capture 'true' object motion vectors from video sequences with or without the camera motion (zoom and/or pan). Experimental results on representative standard video sequences are included to establish the superiority of our filter compared with the traditional median and mean filters

Bandwidth Borrowing Schemes for Instantaneous Video-on-Demand Systems

A controlled multicast scheme provides instantaneous service, but limited server bandwidth causes some user requests to be either delayed or rejected when insufficient free bandwidth is available. Two borrowing schemes are proposed for instantaneous video-on-demand (VOD) that reduce the user request blocking rate by borrowing bandwidth from ongoing video streams when there is insufficient free bandwidth for the server to deliver a new video stream. Both these new schemes have proved to be successful in reducing blocking rate and increasing bandwidth utilization at the expense of temporarily degrading the video quality

A directionally based bandwidth reservation scheme for call admission control

This paper proposes a new advanced Call Admission Control(CAC) strategy involving for the first time, a bandwidth reservation scheme that is influenced by the direction attribute of a mobile terminal (MT). Aside from the Quality-of-Service (QoS) parameters, the direction attribute plays a key role in efficiently reserving resources for MTs supporting multimedia communications for different QoS classes. The framework for a direction-based CAC system is entirely distributed and may be viewed as a message passing system, where MTs inform their neighbouring base stations (BS) not only of their QoS requirements, but also of their mobility parameters. The base stations then predict future demand and reserve resources accordingly, only admitting those terminals that can be adequately supported. The bandwidth reservation scheme proposed in this paper, integrates the direction attribute into the conventional Guard Channel (GC) scheme. Simulation results prove that this new scheme offers significant improvements in both Call Blocking Probability (CBP) and bandwidth utilization, under a variety of differing traffic conditions

Immune checkpoints in circulating and tumor-Infiltrating CD4 + T Cell Subsets in Colorectal cancer patients

Blockade of inhibitory immune checkpoints (ICs) is a promising therapeutic approach; however, it has shown limited success in some cancers including colorectal cancer (CRC). The tumor microenvironment (TME) is largely responsible for response to therapy, and its constituents may provide robust biomarkers for successful immunotherapeutic approaches. In this study, we performed phenotypical characterization and critical analyses of key inhibitory ICs and T regulatory cell (Treg)-related markers on CD4+ T cell subsets in CRC patients, and compared with normal colon tissues and peripheral blood from the same patients. We also investigated correlations between the levels of different CD4+ T cell subsets and the clinicopathologic features including disease stage and tumor budding. We found a significant increase in the levels of CD4+FoxP3+Helios+ T cells, which represent potentially highly immunosuppressive Tregs, in the CRC TME. Additionally, tumor-infiltrating CD4+ T cells upregulated programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), T cell immunoglobulin and mucin domain-3 (TIM-3) and lymphocyte-activation gene 3 (LAG-3). We also characterized the expression of PD-1, CTLA-4, TIM-3, and LAG-3 on different CD4+FoxP3−/+Helios−/+ T cell subsets. Interestingly, we found that CTLA-4, TIM-3, and LAG-3 were mainly co-expressed on FoxP3+Helios+ Tregs in the TME. Additionally, FoxP3high Tregs expressed higher levels of Helios, CTLA-4 and TIM-3 than FoxP3low T cells. These results highlight the significance of Tregs in the CRC TME and suggest that Tregs may hamper response to IC blockade in CRC patients, but effects of different IC inhibition regimes on Treg levels or activity warrants further investigations. We also found that CD4+CTLA-4+ T cells in circulation are increased in patients with advanced disease stage. This study simultaneously provides important insights into the differential levels of CD4+ T cell subpopulations and IC expression in CRC TME, compared to periphery and associations with clinicopathologic features, which could be used as potential biomarkers for CRC progression and response to therapy