825 research outputs found
Generation gap, gender and shopping enjoyment of shopping mall visitors in western province Sri Lanka
Purpose: Going shopping is a major source of relaxation as well as a daily household chore. However, shopping enjoyment is a burgeoning and rather novel concept, and thus, there is a lack of studies within the cohort, especially with regard to the comparison of the shopping experiences of different generations. This paper explores the nature of shopping enjoyment and measures the impact of the generation gap and gender on visitors’ shopping enjoyment in shopping malls, which records a thriving interest.
Design/methodology/approach: In a qualitative survey deploying a convenience sample, 379 usable responses were collected through a self-administered questionnaire from shopping mall visitors in the Western Province of Sri Lanka. Data were analyzed using SPSS (21.0).
Findings: Findings of the study indicated that all four generations considered the atmosphere and the environment to be the most important dimensions. Empirical evidence further suggested that Generation Z and Y have the highest enjoyment in their shopping journey within malls compared to other generations, confirming that youth shoppers are the emerging target group for such businesses. Interestingly, it evidenced that shopping is not remaining as a gendered activity anymore, since it is pleasurable for both females and males.
Originality: This paper makes a significant contribution to the field by studying shopping enjoyment as a multi-dimensional construct in relation to four generations while being the first such attempt at studying this phenomenon.
Implications: Findings are useful for retailers to identify target customers and lucrative markets. Further, shopping malls are required to design to provide more experiences and engagements to customers as a space for pleasure, enjoyment, and entertainment.
 
Wireless sensor network based system for underground chemical plume tracking, A
A real-time subsurface chemical plume monitoring and tracking system is being developed that uses wireless-sensor networking to automatically extract data from underground chemical sensors. This system is aimed at tracking plumes caused by the release of toxic chemicals and biological agents into the environment as a result of accidental spills and improper disposal. Current practice involves manual collection of samples from monitoring wells followed by laboratory analysis, an expensive process taking days to weeks; such a delay reduces the effectiveness of mitigation techniques as well. Virtual Sensor Networks (VSN), a novel resource efficient approach for sensor networking being developed to track the migrating underground plumes, will be applicable to a broad class of problems. Laboratory based experiments and simulations are in progress to demonstrate the feasibility of the approach for large-scale plume tracking.This research is supported in part by Army Research Office and the National Science Foundation.1st place, ISTeC Student Research Poster Contest (April 7, 2008)
Evaluation of the effect of plant growth retardants on vegetative growth, yield components, seed quality and crop maturity of kabuli chickpea
Non-Peer Reviewe
CONSTRUCTION OF A PRECISE GROWTH MODEL TO PREDICT THE NDIVIDUAL STEM VOLUME OF Alstonia macrophylla WALL. EX G. DON
In order to reduce the pressure on existing Natural Forests in Sri Lanka,Forest Department promoted growing timber species as plantations and inhome gardens. Among the suggested species Alstonia macrophylla(Hawarinuga) has recently become popular due to its fast growth rate, ease ofestablishment and timber value. There are about 1913 ha extent of Alstoniamacrophylla plantations at the end of the year 1998 maintained by the ForestDepartment of Sri Lanka. However, this figure must be higher than thatbecause many other private organizations are establishing Alstoniamacrophylla plantations in the wet zone in large scale. This species is alsogrown in home gardens, alleys and borders as non-blocks (non-plantations).However, at present there is no method at present for estimating the stemvolume of this species, which is considered as the most important variable incommercial forestry. Therefore a mathematical model was constructed in thisstudy to predict the individual stem volume of Alstonia macrophylla treesgrown in plantations.Since Alstonia macrophylla is widely found in wet zone of Sri Lanka, studysites were selected from Galle (two even-aged plantations from Pituwala andWattehena Beats) districts. The ages of these plantations were 19 and 16respectively. Ten 0.02 ha circular plots with slope correction were randomlylaid out for each plantation, in order to measure the necessary parametersfrom the individual trees. Diameter at breast height (dbh), total height andheight to the crown base of all the trees inside the plots were measured.Newton's formula was used in this research because it is the most accuratemethod. In order to calculate the volume using the Newton's formula, thestem of each tree was hypothetically divided into 4 -5 sections. Then thebottom, mid and top diameters and section lengths were measured usingSpeigal Relascope and Blume Leiss Altimeter respectively. The final sectionof the tree was assumed as a cone and only the bottom diameter and heightwere used in that particular section. The total volume of each section wasestimated by adding the section volumes calculated using Newton's formulato the volume of the final section.First a theoretical model structure was developed using the relationship ofform factor with volume, height and area at the base. Regression analysis wasused to fit the data into the model. Untransformed as well as transformedcombinations of all variables were tested. In this procedure the combinedvariable (basal area * tree height) was always kept as the first explanatoryvariable. After trying with many combinations of selected variables withvolume, final model was selected using its compatibility with the real world,R2 values, and residual distributions, model bias value and modelingefficiency. The selected models at the preliminary stage indicated very highperformance and insignificant bias. In order to select a final one, the abovemodels were validated with a new set of data. The final selected model in thisstudy to predict the individual stem volume with insignificant bias ofAlstonia macrophylla is; --.jv= 0.659 log BA *Ht + 0.00404 ...fer h
Water Quality in Selected Locations of the Kalu Ganga
Out of the 103 rivers in the country Kalu Ganga is one of the main rivers in Sri Lanka with a length of 129km and a drainage area of 2720 km2. It has the highest discharge volume with a mean annual discharge volume to sea totaling to 8183 mcm. Kalu Ganga originates from the central hills of mountain Sri Pada situated 2100 m above sea level and falls to the sea in Kalutara.The purpose of this research is to analyze the current water quality situation of the Kalu Ganga River and its suitability for human consumption purposes (by comparing with the CEA and SLS standards). It is also the purpose of this research to locate the areas where the river is exposed to massive degradation in water quality and identify the main sources of pollution in those areas.The research study was conducted in the middle and lower reaches of the Kalu Ganga basin. The study was conducted in two phases, the feasibility phase and the detail phase. The water quality of the river was tested using physical, chemical and biological parameters. The water samples from the relevant sampling points were obtained and analyzed in the period between February 2012 and August 2012. For the feasibility study, 13 sampling locations were selected along the main river and at locations where certain tributaries fall to the main river. The sampling points were in a stretch from Ratnapura to Kalutara with approximate distance of about 6-8 km from each sampling point to another. The sampling points for the feasibility study was selected based on criteria such as regional population, land use pattern along the river basin, water intake points of the NWS&DB and previous studies. The parameters tested in the feasibility study were temperature, turbidity, TDS, E. Conductivity, pH, Chloride, Floride, Nitrate, Nitrite, Sulphate, Total Iron, Total Phosphate, Total hardness, Alkalinity, Heavy Metals, COD, BOD, DO, Total coli form and E.coli. The detail study was conducted based on the results of the feasibility study.Based on the results obtained the temperature of the river had an average value of 24̊ C and the pH values were within the range allowed in the CEA standard in most of the locations. The DO levels of the water was greater than the standard values while the BOD values in the river was lower than the standard value prescribed by the CEA standards. The COD values were comparatively higher in the river outfall (46.2mg/l) and in the Nathupana bridge (14.4mg/l) due to the industries located in the surrounding area, but the values were within the standard prescribed by the CEA. The river was not polluted much with the presence of heavy metals. The total coliform count was well below the standard level, while the fecal coliform count was above the standard level especially during the high flow period mainly in sampling points near tributaries. Based on the results obtained from the feasibility study it was decided to concentrate the detail study in the lower reaches of the middle basin and the lower basin of the main river. The sampling points were located in areas from Horana to Kalutara. When selecting sampling points major effluent discharging industries in the river basin were selected as additional sampling points, to identify the affect of the final effluent on the water quality of the river. In total 11 sampling points were selected for the detail study. In the detail study certain parameters tested in the feasibility study was excluded due to tested results being lower than the minimum allowable levels in the standards. New parameters were included in the detail study based on the industries selected. The newly included parameters were free ammonia, color, sulphides, TOC, oil and grease, surfactants, phenolitic compounds and PAH.Keywords: Water quality, BOD, COD, industry effluent
The KMOS^3D Survey: design, first results, and the evolution of galaxy kinematics from 0.7<z<2.7
We present the KMOS^3D survey, a new integral field survey of over 600
galaxies at 0.7<z<2.7 using KMOS at the Very Large Telescope (VLT). The KMOS^3D
survey utilizes synergies with multi-wavelength ground and space-based surveys
to trace the evolution of spatially-resolved kinematics and star formation from
a homogeneous sample over 5 Gyrs of cosmic history. Targets, drawn from a
mass-selected parent sample from the 3D-HST survey, cover the star
formation-stellar mass () and rest-frame planes uniformly. We
describe the selection of targets, the observations, and the data reduction. In
the first year of data we detect Halpha emission in 191
Msun galaxies at z=0.7-1.1 and z=1.9-2.7. In
the current sample 83% of the resolved galaxies are rotation-dominated,
determined from a continuous velocity gradient and , implying
that the star-forming 'main sequence' (MS) is primarily composed of rotating
galaxies at both redshift regimes. When considering additional stricter
criteria, the Halpha kinematic maps indicate at least ~70% of the resolved
galaxies are disk-like systems. Our high-quality KMOS data confirm the elevated
velocity dispersions reported in previous IFS studies at z>0.7. For
rotation-dominated disks, the average intrinsic velocity dispersion decreases
by a factor of two from 50 km/s at z~2.3 to 25 km/s at z~0.9 while the
rotational velocities at the two redshifts are comparable. Combined with
existing results spanning z~0-3, disk velocity dispersions follow an
approximate (1+z) evolution that is consistent with the dependence of velocity
dispersion on gas fractions predicted by marginally-stable disk theory.Comment: 20 pages, 11 figures, 1 Appendix; Accepted to ApJ November 2
Transfer Functions for Protein Signal Transduction: Application to a Model of Striatal Neural Plasticity
We present a novel formulation for biochemical reaction networks in the
context of signal transduction. The model consists of input-output transfer
functions, which are derived from differential equations, using stable
equilibria. We select a set of 'source' species, which receive input signals.
Signals are transmitted to all other species in the system (the 'target'
species) with a specific delay and transmission strength. The delay is computed
as the maximal reaction time until a stable equilibrium for the target species
is reached, in the context of all other reactions in the system. The
transmission strength is the concentration change of the target species. The
computed input-output transfer functions can be stored in a matrix, fitted with
parameters, and recalled to build discrete dynamical models. By separating
reaction time and concentration we can greatly simplify the model,
circumventing typical problems of complex dynamical systems. The transfer
function transformation can be applied to mass-action kinetic models of signal
transduction. The paper shows that this approach yields significant insight,
while remaining an executable dynamical model for signal transduction. In
particular we can deconstruct the complex system into local transfer functions
between individual species. As an example, we examine modularity and signal
integration using a published model of striatal neural plasticity. The modules
that emerge correspond to a known biological distinction between
calcium-dependent and cAMP-dependent pathways. We also found that overall
interconnectedness depends on the magnitude of input, with high connectivity at
low input and less connectivity at moderate to high input. This general result,
which directly follows from the properties of individual transfer functions,
contradicts notions of ubiquitous complexity by showing input-dependent signal
transmission inactivation.Comment: 13 pages, 5 tables, 15 figure
Chronic kidney disease of unknown aetiology in Sri Lanka: is cadmium a likely cause?
<p>Abstract</p> <p>Background</p> <p>The rising prevalence of chronic kidney disease (CKD) and subsequent end stage renal failure necessitating renal replacement therapy has profound consequences for affected individuals and health care resources. This community based study was conducted to identify potential predictors of microalbuminuria in a randomly selected sample of adults from the North Central Province (NCP) of Sri Lanka, where the burden of CKD is pronounced and the underlying cause still unknown.</p> <p>Methods</p> <p>Exposures to possible risk factors were determined in randomly recruited subjects (425 females and 461 males) from selected areas of the NCP of Sri Lanka using an interviewer administered questionnaire. Sulphosalicylic acid and the Light Dependent Resister microalbumin gel filtration method was used for initial screening for microalbuminuria and reconfirmed by the <it>Micral </it>strip test.</p> <p>Results</p> <p>Microalbumnuria was detected in 6.1% of the females and 8.5% of the males. Smoking (p < 0.001), alcohol use (p = 0.003), hypertension (p < 0.001), diabetes (p < 0.001), urinary tract infection (UTI) (p = 0.034) and consumption of water from wells in the fields (p = 0.025) were associated with microalbuminuria. In the binary logistic regression analysis, hypertension, diabetes mellitus, UTI, drinking well water in the fields, smoking and pesticide spraying were found to be significant predictors of microalbuminuria.</p> <p>Conclusions</p> <p>Hypertension, diabetes mellitus, UTI, and smoking are known risk factors for microalbuminuria. The association between microalbuminuria and consumption of well water suggests an environmental aetiology to CKD in NCP. The causative agent is yet to be identified. Investigations for cadmium as a potential causative agent needs to be initiated.</p
The chemical characterization of Nigerian propolis samples and their activity against Trypanosoma brucei.
Profiling of extracts from twelve propolis samples collected from eight regions in Nigeria was carried out using high performance liquid chromatography (LC) coupled with evaporative light scattering (ELSD), ultraviolet detection (UV) and mass spectrometry (MS), gas chromatography mass spectrometry (GC-MS) and nuclear magnetic resonance spectroscopy (NMR). Principal component analysis (PCA) of the processed LC-MS data demonstrated the varying chemical composition of the samples. Most of the samples were active against Trypanosoma b.brucei with the highest activity being in the samples from Southern Nigeria. The more active samples were fractionated in order to isolate the component(s) responsible for their activity using medium pressure liquid chromatography (MPLC). Three xanthones, 1,3,7-trihydroxy-2,8-di-(3-methylbut-2-enyl)xanthone, 1,3,7-trihydroxy-4,8-di-(3-methylbut-2-enyl)xanthone a previously undescribed xanthone and three triterpenes: ambonic acid, mangiferonic acid and a mixture of α-amyrin with mangiferonic acid (1:3) were isolated and characterised by NMR and LC-MS. These compounds all displayed strong inhibitory activity against T.b.brucei but none of them had higher activity than the crude extracts. Partial least squares (PLS) modelling of the anti-trypanosomal activity of the sample extracts using the LC-MS data indicated that high activity in the extracts, as judged from LCMS
2data, could be correlated to denticulatain isomers in the extracts
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