Readiness of the Port of Colombo as a Mega Hub Port for Transshipment Containers

The Colombo Port has become a hub port for transshipment containers in the South-Asia region mainly due to its location advantage and have further carved out a niche linking feeder connections in the Indian subcontinent trade to main sea routes on the back of its access to the Indian Ocean. During past couple of decades major ports around the world have faced significant challenges due to rapid evolvement in marine technology and international logistical system. Primarily there were two major thrusts have been impacting the seaports which identified as ‘Increased specialization of ship design’ and the ‘Growth in ship size’. These two aspects of ship specialization and capacity enhancement that were continued to progress resulted a greater demand in Ports and container terminals to invest on improvements to equipment and ports infrastructure. Each subsequent generation of containership which evolved has not only created new challenges to ports around the world, but also limited the number of port calls. Presently only one deep water container terminal available in Port of Colombo to handle modern day Ultra large container carriers (ULCC’s)

EVALUATION OF URBAN AIR POLLUTION COST A CASE STUDY IN THE COLOMBO CITY

Air pollution is arguably the most important. in terms of economics cost, of thevarious types of pollution caused by transport and industrial activities and itseffects have been widely studied in other countries. However, direct studies havenot been undertaken to measure the economics cost of air pollution in Sri Lanka.Concern for air pollution in Sri Lanka is focused mainly in Colombo. AlthoughColombo air pollution level is less than many Asian countries, recent monitoringresults show that air pollution from particulate matter and Sulfur is well above theWHO recommended levelThe contingent valuation method was used to estimate the air pollution cost anddata was collected from a contingent valuation survey carried out in the Fort andPettah areas. Respondents' willingness to pay values were obtained for ahypothetical market presented. The results were consistent with the economictheory. Aggregated cost of air pollution for the country was Rs.55 million peryear. This value may help cost benefit analysis of air quality managementprogrammes and other related development policy and programs in Sri Lanka.

GLOBAL VALUES FOR LOCAL RESOURCES A CONTINGENT VALUATION APPROACH FOR SINHARAJA RAIN FOREST RESERVE IN SRI LANKA

Tropical forests are sources of important global use and non-use values. However. thesevalues are not often reflected in global markets, thus creating global externalities. In orderto demonstrate glohal values of tropical rain forests. this study sought to estimate globalnon-use values of the Sinharaja Rain Forest Reserve in Sri LankaA contingent valuation survey was carried out in the United Kingdom in order to obtainexistence and bequest values for the forest. Open ended questions were asked from theselected sample of respondents 10 obtain their maximum willingness 10 pay.The non use values elicited for the forest were related to variation in respondents' socioeconomic status. Multiple regression analysis showed that income and education hadpositive coefficients for hoth existence and bequest values.The results showed that remote populations have positive values for tropical rain forest.Thc implications of these results to the use of contingent valuation methodology forestimating total economic values of forests in developing countries is discussed. and theparticular implications of demonstrating the magnitude of external benefits that couldprovide insights into the correction of global economic failures highlighted

Economics of urban amenities A contingent valuation approach for Bolgoda lake

Bolgoda Lake is known as the largest fresh water body in Colombo Urban Area (CUA) and situatedin the Southern boundary ofCUA. It covers 1,245 hectares. There are 14 Divisional secretariat (OS)divisions and 105 Grama Niladary (GN) divisions. Bolgoda Lake lies along the highly popularizedtownships and it provides a variety of environmental services such as natural environment for fisheriesproduction and estuary function; ground water recharge, potable water supply; recreation/ tourism;and )1atural biotic habitat. In CUA, there are very few lakes like Bolgoda, which provides aestheticvalues for the urban environment. Environment of the Bolgoda Lake is threatened by the disposal ofliquid and solid waste, agricultural run-off, sedimentation and congestion due to recreational uses.However, there wi II be an increasing demand for the environmental services produced by the BolgodaLake in the future.Objectives of the present study are to identify the environmental benefits of the Lake and estimateeconomic value of selected environmental benefits. A pilot survey was carried out and five major usergroups were identified; fishermen, hotel owners, boat owners, recreational users (for swimming andhotel visiting) and indirect users. Selected study area for the present study belongs to five GN divisionsfrom Moratuwa and Panadura OS divisions. Contingent valuation method was applied to estimate theeconomic value of the Bolgoda Lake. Users' willingness to pay (WTP) was elicited on a pre-testedhypothetical market.Depending on the WTP values, the 5 user groups were regrouped into two categories, namely User I(heavy dependency) and User 1/ (less dependency). WTP values per household per year for the UserI and User II are Rs.18, 600 and 514.3 respectively. Estimated economic value of the Bolgoda Lakefor the study area is Rs. 84,192.7 (US$ 809.55) per hectare per year. Regression analysis was carriedout to identify the socio economic characteristics of the users that affect the WTP value of the users.The results were consistent with the theory. However, the values of the study area have not beenextrapolated to the whole lake, due to the high variability of the sample mean from place to place.It was clear that the Bolgoda Lake is a valuable aesthetic asset in the CUA and it should be judiciouslymanaged for sustain the provision of environmental services. However, the ultimate decision over theusefulness of the lake has to be based on weighing the estimated value of the environmental servicesof the Lake against the value of the use of lake as a sink for domestic and industrial waste.

EXTENDED COST BENEFIT ANALYSIS OF A BIOGAS GENERATION PLANT

Solid waste is a growing problem in Sri Lanka in the absence of proper managementmeasures. Development and implementation of a National strategy for municipal solidwaste management is essential in order to reduce environmental, social and the economicproblems associated with the present disposal practices. Such strategies however, need tobe subjected to proper economic analysis in order to arrive at informed decisions. Thispaper presents an extended cost benefit analysis of a biogas generation plant that usesmunicipal solid waste as the raw material.To dispose vegetable market garbage available in Wattala, Kandana and Ja-ela areas a640 Mt capacity biogas/ bio fertilizer project has been housed at Muthurajawela (alongHamilton canal, Elakanda), by the National Engineering Research & DevelopmentCenter of Sri Lanka (NERDC) which uses Dry Batch Anaerobic Digester Technology.Among the other biological treatment options, anaerobic digestion is the most costeffective, due to the high-energy recovery linked to the process and its limitedenvironmental impacts.Economic analysis has been carried out to identify environmental costs and benefitsassociated with the above project. Several environmental valuation methods have beenapplied to value the identified costs and benefits. The main benefit of reduction ofmunicipal solid waste has been estimated by contingent valuation method using samplesfrom Wattala-Mabola, Ja-ela, and Peliyagoda local authority areas. Another benefit is thereduction of green house has emission due to the reduction of open dumping. Greenhouse gas (methane) emission from solid waste was estimated through Sholl Canionmodel and valued using avoided global damage cost approach. Benefits of biogas asenergy and organic fertilizers and employment benefits were estimated by market basedapproachesThe project is viable from economy and environment point of view with net present valueof Rs 142 million for a 20-year period with 10% discount rate. This analysis provides ajustification for undertaking solid waste management strategies in a technologically,environmentally and economically viable manner

The level set method for the two-sided eigenproblem

We consider the max-plus analogue of the eigenproblem for matrix pencils Ax=lambda Bx. We show that the spectrum of (A,B) (i.e., the set of possible values of lambda), which is a finite union of intervals, can be computed in pseudo-polynomial number of operations, by a (pseudo-polynomial) number of calls to an oracle that computes the value of a mean payoff game. The proof relies on the introduction of a spectral function, which we interpret in terms of the least Chebyshev distance between Ax and lambda Bx. The spectrum is obtained as the zero level set of this function.Comment: 34 pages, 4 figures. Changes with respect to the previous version: we explain relation to mean-payoff games and discrete event systems, and show that the reconstruction of spectrum is pseudopolynomia

Axonal inclusions in spinocerebellar ataxia type 3

Protein aggregation is a major pathological hallmark of many neurodegenerative disorders including polyglutamine diseases. Aggregation of the mutated form of the disease protein ataxin-3 into neuronal nuclear inclusions is well described in the polyglutamine disorder spinocerebellar ataxia type 3 (SCA3 or Machado–Joseph disease), although these inclusions are not thought to be directly pathogenic. Neuropil aggregates have not yet been described in SCA3. We performed a systematic immunohistochemical study of serial thick sections through brains of seven clinically diagnosed and genetically confirmed SCA3 patients. Using antibodies against ataxin-3, p62, ubiquitin, the polyglutamine marker 1C2 as well as TDP-43, we analyzed neuronal localization, composition and distribution of aggregates within SCA3 brains. The analysis revealed widespread axonal aggregates in fiber tracts known to undergo neurodegeneration in SCA3. Similar to neuronal nuclear inclusions, the axonal aggregates were ubiquitinated and immunopositive for the proteasome and autophagy associated shuttle protein p62, indicating involvement of neuronal protein quality control mechanisms. Rare TDP-43 positive axonal inclusions were also observed. Based on the correlation between affected fiber tracts and degenerating neuronal nuclei, we hypothesize that these novel axonal inclusions may be detrimental to axonal transport mechanisms and thereby contribute to degeneration of nerve cells in SCA3

In silico evolution of signaling networks using rule-based models: bistable response dynamics

One of the ultimate goals in biology is to understand the design principles of biological systems. Such principles, if they exist, can help us better understand complex, natural biological systems and guide the engineering of de novo ones. Towards deciphering design principles, in silico evolution of biological systems with proper abstraction is a promising approach. Here, we demonstrate the application of in silico evolution combined with rule-based modelling for exploring design principles of cellular signaling networks. This application is based on a computational platform, called BioJazz, which allows in silico evolution of signaling networks with unbounded complexity. We provide a detailed introduction to BioJazz architecture and implementation and describe how it can be used to evolve and/or design signaling networks with defined dynamics. For the latter, we evolve signaling networks with switch-like response dynamics and demonstrate how BioJazz can result in new biological insights on network structures that can endow bistable response dynamics. This example also demonstrated both the power of BioJazz in evolving and designing signaling networks and its limitations at the current stage of development.Comment: 24 pages, 7 figure

Propagation of kinetic uncertainties through a canonical topology of the TLR4 signaling network in different regions of biochemical reaction space

<p>Abstract</p> <p>Background</p> <p>Signal transduction networks represent the information processing systems that dictate which dynamical regimes of biochemical activity can be accessible to a cell under certain circumstances. One of the major concerns in molecular systems biology is centered on the elucidation of the robustness properties and information processing capabilities of signal transduction networks. Achieving this goal requires the establishment of causal relations between the design principle of biochemical reaction systems and their emergent dynamical behaviors.</p> <p>Methods</p> <p>In this study, efforts were focused in the construction of a relatively well informed, deterministic, non-linear dynamic model, accounting for reaction mechanisms grounded on standard mass action and Hill saturation kinetics, of the canonical reaction topology underlying Toll-like receptor 4 (TLR4)-mediated signaling events. This signaling mechanism has been shown to be deployed in macrophages during a relatively short time window in response to lypopolysaccharyde (LPS) stimulation, which leads to a rapidly mounted innate immune response. An extensive computational exploration of the biochemical reaction space inhabited by this signal transduction network was performed via local and global perturbation strategies. Importantly, a broad spectrum of biologically plausible dynamical regimes accessible to the network in widely scattered regions of parameter space was reconstructed computationally. Additionally, experimentally reported transcriptional readouts of target pro-inflammatory genes, which are actively modulated by the network in response to LPS stimulation, were also simulated. This was done with the main goal of carrying out an unbiased statistical assessment of the intrinsic robustness properties of this canonical reaction topology.</p> <p>Results</p> <p>Our simulation results provide convincing numerical evidence supporting the idea that a canonical reaction mechanism of the TLR4 signaling network is capable of performing information processing in a robust manner, a functional property that is independent of the signaling task required to be executed. Nevertheless, it was found that the robust performance of the network is not solely determined by its design principle (topology), but this may be heavily dependent on the network's current position in biochemical reaction space. Ultimately, our results enabled us the identification of key rate limiting steps which most effectively control the performance of the system under diverse dynamical regimes.</p> <p>Conclusions</p> <p>Overall, our <it>in silico </it>study suggests that biologically relevant and non-intuitive aspects on the general behavior of a complex biomolecular network can be elucidated only when taking into account a wide spectrum of dynamical regimes attainable by the system. Most importantly, this strategy provides the means for a suitable assessment of the inherent variational constraints imposed by the structure of the system when systematically probing its parameter space.</p

Protein Scaffolds Can Enhance the Bistability of Multisite Phosphorylation Systems

The phosphorylation of a substrate at multiple sites is a common protein modification that can give rise to important structural and electrostatic changes. Scaffold proteins can enhance protein phosphorylation by facilitating an interaction between a protein kinase enzyme and its target substrate. In this work we consider a simple mathematical model of a scaffold protein and show that under specific conditions, the presence of the scaffold can substantially raise the likelihood that the resulting system will exhibit bistable behavior. This phenomenon is especially pronounced when the enzymatic reactions have sufficiently large KM, compared to the concentration of the target substrate. We also find for a closely related model that bistable systems tend to have a specific kinetic conformation. Using deficiency theory and other methods, we provide a number of necessary conditions for bistability, such as the presence of multiple phosphorylation sites and the dependence of the scaffold binding/unbinding rates on the number of phosphorylated sites