796 research outputs found
Evolution, present status and issues concerning small tank systems in Sri Lanka [Small tanks in Sri Lanka: evolution, present status and issues]
Tank irrigationHydrologyWater qualityIrrigation managementWater managementWater distributionWatershedsIrrigation designMaintenanceFarming systemsGovernmental interrelationsSmall scale systemsVillagesHistory
Formation and destruction of polycyclic aromatic hydrocarbon clusters in the interstellar medium
The competition between the formation and destruction of coronene clusters
under interstellar conditions is investigated theoretically. The unimolecular
nucleation of neutral clusters is simulated with an atomic model combining an
explicit classical force field and a quantum tight-binding approach.
Evaporation rates are calculated in the framework of the phase space theory and
are inserted in an infrared emission model and compared with the growth rate
constants. It is found that, in interstellar conditions, most collisions lead
to cluster growth. The time evolution of small clusters (containing up to 312
carbon atoms) was specifically investigated under the physical conditions of
the northern photodissociation region of NGC 7023. These clusters are found to
be thermally photoevaporated much faster than they are reformed, thus providing
an interpretation for the lowest limit of the interstellar cluster size
distribution inferred from observations. The effects of ionizing the clusters
and density heterogeneities are also considered. Based on our results, the
possibility that PAH clusters could be formed in PDRs is critically discussed.Comment: 14 pages, 14 figures. Astronomy & Astrophysics, accepted for
publicatio
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Mobile Web services authentication using SAML and 3GPP generic bootstrapping architecture
In this paper we present a platform for the direct consumption of web services by a Mobile Station. We give an architectural solution where Mobile Operators play the role of Trusted Third Parties supplying service credentials that allow a co-located 3GPP Network Application Function and Liberty-enabled Identity Provider entity to implement a controlled Shopping Mall service to Mobile Stations from multiple trust domains. We consider both the protocol and the structure and syntax of the various tokens required to minimise service latency over the bandwidth and performance constrained mobile system, whilst providing adequate security services to protect against the perceived threat model. To validate our proposal we have developed code to create a Web Service test scenario using SAML authentication tokens utilising readily available J2ME, Java Card, J2SE and J2EE platforms, Web Services tools from Apache, the KToolBar emulator from Sun, and the JCOPS suite of tools for Java Card applet development
Use of Mobile Phones for Infant and Young Child Feeding Counseling in Sri Lankan Tea Estates: A Formative Study
Despite the availability of free health services, children residing in Sri Lanka’s less developed plantation sector are more likely to be undernourished than children in urban and rural sectors. Hence, we need new approaches to improve their nutritional status. One promising approach involves mobile health initiatives, which is used effectively in other countries in primary health care settings. We studied the nature of mobile phone use in this community, and their perceptions on using m-health counseling for infant and young child feeding. Focus group discussions and in-depth interviews were the study methods. We found that mobile phone usage is common in this community hence; m-health platform could be a promising initiative to strengthen the existing face to face nutritional advice provided by the field health workers to improve the nutritional status of children
Use of high density SNP genotypes to determine the breed composition of cross bred dairy cattle in smallholder farms: Assessment of reproductive and health performance
Reproductive performance and disease data were recorded for 2 years on 1,824 dairy cows in smallholder farms using participatory approaches and onfarm recording. Most animals experienced one service to conception. Calving intervals were long, ranging between 261 and 761 days, with an average of 451±101days. Herd level of production (HeL) had significant effect on calving interval. However, there was no difference between crossbreds with different levels of exotic breed percentage or in different HeL classes in disease incidence. Most animals had less than 2 treatment events, despite the high disease burden in the study areas. Mortality rates were low, ranging from 2.13% to 2.65%. Even though the crossbred animals had higher performance compared to indigenous animals, the gains obtained were below what would be possible with better management. These results suggest that crosses with low exotic proportions would be the most optimal for the production systems studied
A novel use of high density SNP assays to optimize choice of different crossbred dairy cattle genotypes in smallholder systems in East Africa
We present use of SNP technologies to obtain for the first time, rapid, large-scale, in situ estimates of performance of crossbred cows in smallholder herds. Compared to historical approaches, our approach allowed optimum crossbreed choices to be determined more rapidly and without question about the relevance of the environment. High-density SNP assays were used to estimate breed composition for a monitored population comprising 1292 cows from 610 smallholder farms in Kenya. The achieved milk yields are much lower than generally assumed and lactation curves are very flat out to 400 days. In poor production environments, lower grade crosses (containing <60% exotic dairy alleles) had the same yield as high grade crosses. Allowing for the larger size and maintenance requirements of high grade exotics, lower grade exotics will be the most economically productive animals in these environments
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Functional trait variation related to gap dynamics in tropical moist forests: a vegetation modelling perspective
The conventional representation of Plant Functional Types (PFTs) in Dynamic Global Vegetation Models (DGVMs) is increasingly recognized as simplistic and lacking in predictive power. Key ecophysiological traits, including photosynthetic parameters, are typically assigned single values for each PFT while the substantial trait variation within PFTs is neglected. This includes continuous variation in response to environmental factors, and differences linked to spatial and temporal niche differentiation within communities. A much stronger empirical basis is required for the treatment of continuous plant functional trait variation in DGVMs. We analyse 431 sets of measurements of leaf and plant traits, including photosynthetic measurements, on evergreen angiosperm trees in tropical moist forests of Australia and China. Confining attention to tropical moist forests, our analysis identifies trait differences that are linked to vegetation dynamic roles. Coordination theory predicts that Rubisco- and electron-transport limited rates of photosynthesis are co-limiting under field conditions. The least-cost hypothesis predicts that air-to-leaf CO2 drawdown minimizes the combined costs per unit carbon assimilation of maintaining carboxylation and transpiration capacities. Aspects of these predictions are supported for within-community trait variation linked to canopy position, just as they are for variation along spatial environmental gradients. Trait differences among plant species occupying different structural and temporal niches may provide a basis for the ecophysiological representation of vegetation dynamics in next-generation DGVMs
Merkel cell carcinoma masquerading as cellulitis: A case report and review of the literature
© 2018 Multimed Inc. Merkel cell carcinoma (MCC) is an uncommon malignancy of the skin arising from cells located in the deeper layers of the epidermis called Merkel cells. This malignancy rarely presents as a metastatic disease, and the field is therefore deficient in regards to management. We report the case of a 49-year-old woman who presented with a presumptive diagnosis of osteomyelitis of the left fifth digit that was resistant to treatment with antibiotics; she underwent debridement of the digit that revealed MCC and was later to have metastatic disease to her lungs, liver, and musculoskeletal system. The management of MCC, although simple in the early stage of the disease, can become challenging when it is more advanced. Multiple new modalities for its treatment have emerged over the last few years, and more recently, clinical trials are being conducted for the use of immunotherapy agents in the treatment of this malignancy
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