Urban air quality in the Asian region

Over the past decade, member states of the Regional Co-operation Agreement (RCA), an intergovernmental agreement for the East Asia and Pacific region under the auspices of the IAEA with the assistance of international organizations and financial institutions such as the World Bank and the Asian Development Bank, have started to set in place policies and legislation for air pollution abatement. To support planning and evaluate the effectiveness of control programs, data are needed that characterizes urban air quality. The focus of this measurement program describe in this report is on size segregated particulate air pollution. Such airborne particulate matter can have a significant impact on human health and urban visibility. These data provide the input to receptor models that may permit the mitigation of these impacts by identification and quantitative apportionment of the particle sources. The aim of this report is to provide an overview of the measurements of concentrations and composition of particulate air pollution in two size fractions across the participating countries. For many of the large cities in this region, the measured particulate matter concentrations are greater than air quality standards or guidelines that have been adopted in developed countries.     

Transport layer statistical multicast based on the XTP bucket algorithm

Multicast or point-to-multipoint transmission is becoming a major issue for supporting distributed multimedia applications. In this paper, we analyze the service provided by theXtp reliable multicast. We discover several problems and drawbacks, such as multiple retransmission of the same data packets or the protocol inefficiency when performing with large group size and non-broadcast networks. To overcome some of these problems, we introduce new constraints at the sender side to prevent any unnecessary retransmissions. We introduce the service semantic calledstatistical reliable to cope with large group size while keeping a high level of reliability (related to error recovery issues). The quality of service provided by this modified protocol is assessed by simulation experiments for two different network environments :Fddi andAtm. We show that the reliability is almost binary, i.e. all reliable or unreliable at all. If the parameters are correctly sized, we can expect to get an all reliable semantic while using the statistical reliable protocol with the benefit of low protocol overhead. We are now working on a modified version of the proposed protocol to specifically adressAtm based networks.     

A tree-based stacking ensemble technique with feature selection for network intrusion detection

Applied Intelligence - Several studies have used machine learning algorithms to develop intrusion systems (IDS), which differentiate anomalous behaviours from the normal activities of network...     

Evaluation of tropical plants containing tannin on in vitro methanogenesis and fermentation parameters using rumen fluid

BACKGROUND: Methane (CH₄) produced during ruminal fermentation represents a loss of 10–11% of gross energy intake. The use of browse species containing tannin as feed supplement for ruminants tends to increase in order to reduce CH₄ production. The present study was conducted to evaluate some tropical plants containing tannin as feed supplement (200 g kg^?1) on in vitro CH₄ production and fermentation parameters. RESULTS: The crude protein (CP) content ranged from 87 to 390 g kg^?1 dry matter (DM) and was highest in Sesbania grandiflora (L.) Poiret. The neutral detergent fibre (NDF) concentration was highest in Pennisetum purpureum Schumach (725 g kg^?1 DM) and lowest in S. grandiflora (330 g kg^?1 DM). The ranking order of plants based on their total tannin content was Acacia mangium Willd. > Biophytum petersianum Klotzch > Jatropa curcas Linnaeus > Psidium guajava Linnaeus > Phaleria papuana > Persea americana Mill. > S. grandiflora. Methane gas production after 48 h of incubation was significantly (P < 0.05) lower with inclusion of A. mangium (PP + AM), B. petersianum (PP + BP), J. curcas (PP + JC) or P. guajava (PP + PG) as compared to control feed (PP). There was negative correlation between total tannin content and CH₄ production at 48 h of incubation (r = ? 0.76). Concentration NH₃‐N was significantly (P < 0.01) higher with inclusion of S. glandiflora. Inclusion of P. guajava significantly (P < 0.05) suppressed protozoa population by 49.7% relative to control feed (PP). CONCLUSION: It was concluded that A. mangium, B. petersianum, J. curcas and P. guajava have potential to be used as a feed supplement to reduce CH₄ production in ruminants. Copyright © 2009 Society of Chemical Industry     

A critical role for amino-terminal glutamine/asparagine repeats in the formation and propagation of a yeast prion

The yeast [PSI+] factor propagates by a prion-like mechanism involving self-replicating Sup35p amyloids. We identified multiple Sup35p mutants that either are poorly recruited into, or cause curing of, wildtype amyloids in vivo. In vitro, these mutants showed markedly decreased rates of amyloid formation, strongly supporting the protein-only prion hypothesis. Kinetic analysis suggests that the prion state replicates by accelerating slow conformational changes rather than by providing stable nuclei. Strikingly, our mutations map exclusively within a short glutamine/asparagine-rich region of Sup35p, and all but one occur at polar residues. Even after replacement of this region with polyglutamine, Sup35p retains its ability to form amyloids. These and other considerations suggest similarities between the prion-like propagation of [PSI+] and polyglutamine-mediated pathogenesis of several neurodegenerative diseases.     

Nucleotide polymorphisms in the alpha2 gene define multiple alleles that are associated with differences in platelet alpha2 beta1 density

Three allelic differences in the alpha2 gene are associated with expression levels of the alpha2beta1 integrin on the platelet surface. We have previously defined two linked silent polymorphisms in the alpha2 gene coding region at nucleotides 807 (C or T) and 873 (G or A). We have now identified one rarer nucleotide polymorphism in the coding region at nucleotide 837 (T or C) and four additional linked polymorphisms within the introns that flank these coding sequences. Moreover, we have determined that the alloantigenic Br polymorphism, which resides in a distal coding region at nucleotide 1648, is also linked to the 837 polymorphism. Thus, three alpha2 gene alleles, defined by eight nucleotide polymorphisms, have now been discovered. Allele 1 (807T/837T/873A/Brb) is associated with increased levels of alpha2beta1; allele 2 (807C/837T/873G/Brb) and allele 3 (807C/837C/873G/Bra) are each associated with lower levels of alpha2beta1. Finally, we also show here that the rate of platelet attachment to type I collagen in whole blood under conditions of high shear rate (1,500/s) is proportional to the density of alpha2beta1 receptors on the platelet surface. Thus, the density of platelet alpha2beta1 could have an important impact on platelet adhesion to collagen in whole blood and therefore on platelet function in vivo, contributing to an increased risk of thrombosis or to bleeding in relevant disease states.     

Scenariopolis: the civil engineering systems policy research laboratory

This paper describes a system dynamics model of a hypothetical region. The region provides an environment for three typical civil engineered systems; water resource, sewage treatment and urban transportation. The interaction of the key parameters of each system within the system, as well as among the systems, are examined through scenario analysis using simulation and analytical techniques.     

Agglomerate strength and dispersion of pharmaceutical powders

This study aims to investigate quantitatively the direct correlation between the mechanical strength of powder agglomerates and their dispersion into aerosols by a dry powder inhaler. Agglomerates of mannitol as a model drug-only formulation were prepared by a rolling method followed by exposure to various relative humidity (RH: 55%, 82%, 86% and 90%). The agglomerate strength was obtained from the compression of single agglomerates at a selected speed rate using an Instron testing machine. The dispersion performance (FPF_Loaded) was determined at flow rates of 60 and 100 l min^?1 using an Aeroliser^® coupled to a multistage liquid impinger. Results showed an inverse linear relationship between the agglomerate strength and the dispersion performance. An increase in strength from 3 to 183 kPa resulted in a significant drop (P<0.05) of 18% in the FPF_Loaded. Agglomerates containing ‘solid bridges’ exhibited higher strength (three to eight times) and lower FPF (5–15%, corresponding to 86% and 90% RH) compared to those containing ‘liquid bridges’. These results have provided direct information on the agglomerate strength and its quantitative relationship with powder aerosol performance.     

Numerical Analyses and Monitoring Performance of Residual Soil Slopes

Changes in the pore-water pressure of unsaturated soil slopes due to rainwater infiltration comprise a crucial factor which affects the shear strength of soils and may trigger slope failures. Two residual soil slopes in two main geological formations in Singapore, the Bukit Timah Granite and the sedimentary Jurong Formation, were fully instrumented. Real-time monitoring systems were developed to examine the pore-water pressure, the rainfall and the groundwater level of the slopes for over a year. The characteristics of the pore-water pressure distributions in both slopes during rainfall were highlighted and compared. The monitoring results indicate that the residual soil slope of the Bukit Timah Granite has a thicker unsaturated zone due to a deeper groundwater table than the residual soil slope of the sedimentary Jurong Formation. A higher permeability of the residual soil of the Bukit Timah Granite results in more rapid changes in negative pore-water pressure due to rainwater infiltration than the residual soil of the sedimentary Jurong Formation. Therefore, the residual soil slope of the Bukit Timah Granite differs from the residual soil slope of the sedimentary Jurong Formation in the changes in shear strength and the variations in the factor of safety during rainfall. The differing characteristics of the pore-water pressure responses during rainfall for these two residual soil slopes are analyzed in the present study based on the results of field measurements and numerical analyses.