Comparing nanofiltration membranes effectiveness for inorganic and organic compounds removal from a wastewater-reclamation plant's micro-filtered water

The study compared five NF membranes with varied water contact angles and molecular weight cut-off (MWCO) values for their effectiveness to remove dissolved organic carbon (DOC) and inorganic ions from micro-filtered water obtained from a wastewater-reclamation plant. The NF 90 membrane with the highest contact angle (790, least hydrophilic) and one with the lowest MWCO value ((90-200 Da) was the most efficient in removing DOC (88% rejection compared to 37-84% for the others) and inorganics (75% electrical conductivity rejection compared to 9-27% for the others). Of the 10 organic micropollutants in the feed water, >90% of 7 were removed

Emergence of Order in Textured Patterns

A characterization of textured patterns, referred to as the disorder function \bar\delta(\beta), is used to study properties of patterns generated in the Swift-Hohenberg equation (SHE). It is shown to be an intensive, configuration-independent measure. The evolution of random initial states under the SHE exhibits two stages of relaxation. The initial phase, where local striped domains emerge from a noisy background, is quantified by a power law decay \bar\delta(\beta) \sim t^{-{1/2} \beta}. Beyond a sharp transition a slower power law decay of \bar\delta(\beta), which corresponds to the coarsening of striped domains, is observed. The transition between the phases advances as the system is driven further from the onset of patterns, and suitable scaling of time and \bar\delta(\beta) leads to the collapse of distinct curves. The decay of $\bar\delta(\beta)$ during the initial phase remains unchanged when nonvariational terms are added to the underlying equations, suggesting the possibility of observing it in experimental systems. In contrast, the rate of relaxation during domain coarsening increases with the coefficient of the nonvariational term.Comment: 9 Pages, 8 Postscript Figures, 3 gif Figure

A Perspective on Management of House crow (Corvus splendens) in the City of Colombo

House crow (Corvus splendens) is considered as a nuisance animal in the City of Colombo. A roost count method was employed to determine the population size of house crow and their distribution in different wards of the city. Main and link roads of the 47 wards of the city were patrolled during early evening hours to take population counts. Also, direct observations were done to study the biological enemies of crows during day and night. In addition, day time census of house crow and assessment of availability of open garbage dumps was carried out in three selected wards. Current population size of house crow in the City of Colombo was estimated as 101,100 (2018). Using the previous population estimates of crows in the city; 1980-50,000 (Subasinghe and Samad); 1992-70,000 (Dayawansa and Kotagama); 2001-118,500 (Keeragala and Dayawansa), 2006-124,330 (Dayawansa et al.) and 2012-98,350 (Dayawansa unpublished); a population growth curve was constructed. Population growth depicted a logistic model and rate of growth (r) determined by a differential equation depicted three distinct phases on the sigmoid curve and a carrying capacity (K). A positive significant relationship between availability of food resources (garbage) and crow abundance was evident (Linear Regression p<0.05). A positive correlation between availability of trees and crow abundance was evident, however, it was not statistically significant. Total number of roosts has increased significantly from 1992 to 2018 due to increased occurrence of small and medium roosts (One-Way ANOVA: p<0.05). Ironically, there is a decrease of occurrence of very large roosts and large roosts. Variety of trees occupied as roosting sites has increased from 34 to 46 species from 1992 to 2018. House crow population has shown a logistic growth and reached a carrying capacity due to limited availability of resources such as food and breeding sites. It was observed that crows avoid occupying areas where Brown hawk owls inhabit. Control of population size of house crow could be satisfactorily done by manipulating the availability of food resources by implementing an efficient garbage management strategy in the city. In addition, augmenting the top levels of the trophic pyramid by supporting the abundance of nocturnal predators such as Brown hawk owl and Barn owl can reduce the crow populations. Implementation of artificial population control methods such as destroying eggs and culling of adults would be thoroughly unnecessary to control House Crow population in the City of Colombo.Keywords: House Crow, Nuisance species, Logistic growth model, Population managemen

The Phase Structure of an SU(N) Gauge Theory with N_f Flavors

We investigate the chiral phase transition in SU(N) gauge theories as the number of quark flavors, $N_f$, is varied. We argue that the transition takes place at a large enough value of $N_f$ so that it is governed by the infrared fixed point of the $\beta$ function. We study the nature of the phase transition analytically and numerically, and discuss the spectrum of the theory as the critical value of $N_f$ is approached in both the symmetric and broken phases. Since the transition is governed by a conformal fixed point, there are no light excitations on the symmetric side. We extend previous work to include higher order effects by developing a renormalization group estimate of the critical coupling.Comment: 34 pages, 1 figure. More references adde

Picture Story Short thorax and disproportionate dwarf ism due to Kniest dysplasia

A breastfed male infant aged six weeks presented with constipation and weight loss. He was the third born to a 33 year old mother in a non-consanguineous marriage. Both siblings were normal. Abnormalities observed were: short length (crown-toheel 46cm), disproportionate body proportions, short barrel shaped chest (Figure 1), a relatively large head, kyphoscoliosis, enlarged knees and elbows with limited range of active and passive movements, bilateral inguinal herniae, flat facies, prominent eyes and a wide posterior cleft palate. Cardiovascular, respiratory, abdominal and neurological examinations were normal. X rays showed vertebral clefts in thoracic spine (Figures 2 & 3), flared metaphyses and large epiphyses in femur and tibia (Figure 4). Expressed breast milk fed using a long teat corrected weight loss and constipation. Cleft palate repair was planned for nine months of age. Herniotomy was performed. On follow up at four months he had satisfactory weight gain and normal development

A case of hereditary persistence of fetal haemoglobin

(Key words: hereditary persistence of fetal haemoglobin, HPFH

Water Pollution abatement programme, The Czech republic Pollution abatement analysis and strengthening of water resources management, Odra River Catchment, phase II

Odra river is extremely polluted by organic matter, nitrates, ammonia, phosphorus, bacteria, particles, heavy metals and other micro pollutants from municipalities, industries and agriculture. The poor water quality severely affects the ecology and represents a risk to human health. The water has a very limited value of use. This report presents an abatement programme with both technical and accompanying measures. In order to identify the major polluters several multi criteria analysis have been developed, discussed and evaluated. Technical measures for 23 "Hot spots" are proposed and ranked according to the cost/benefit ratio. Measures for agriculture have been based on previous work. The proposed abatement programme gives a significant reduction of the total pollution discharges in the region, and improves both local and regional water quality. The abatement programme will also contribute to the Czech Government's obligations to reduce the pollution to the Baltic Sea. Accompanying measures (policy, administrative including legal and economic measures) have been addressed in detail. The water and environmental management systems has undergone tremendous changes since the "Velvet Revoution" and there is no longer time for major restructuring. The recommendations which are made in this report regarding accompanying measures are designed to make the environmental management function, and are at this stage mostly for studies and experimental project. The report has been prepared jointly by Czech and Norwegian Scientists.Statens forurensningstilsyn (SFT