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

Balanced Truncation Model Reduction of a Nonlinear Cable-Mass PDE System with Interior Damping

We consider model order reduction of a nonlinear cable-mass system modeled by a 1D wave equation with interior damping and dynamic boundary conditions. The system is driven by a time dependent forcing input to a linear mass-spring system at one boundary. The goal of the model reduction is to produce a low order model that produces an accurate approximation to the displacement and velocity of the mass in the nonlinear mass-spring system at the opposite boundary. We first prove that the linearized and nonlinear unforced systems are well-posed and exponentially stable under certain conditions on the damping parameters, and then consider a balanced truncation method to generate the reduced order model (ROM) of the nonlinear input-output system. Little is known about model reduction of nonlinear input-output systems, and so we present detailed numerical experiments concerning the performance of the nonlinear ROM. We find that the ROM is accurate for many different combinations of model parameters

Increasing mental health capacity in a post-conflict country through effective professional volunteer partnerships: A series of case studies with government agencies, local NGOs and the diaspora community

The focus of this paper is on working in partnership with local practitioners and communities to strengthen local capacity building in the area of mental health and well-being in Sri Lanka. This paper will examine the context, organizing concepts, organizational processes, and the development of good working relationships and partnership building behind this work. Our involvement was based on requests which came to the authors as a result of their previous work in Sri Lanka over several decades. This work had been undertaken on behalf of the UK-Sri Lanka Trauma Group (UKSLTG), a UK-based charity which was set up in 1994, and of which the authors are founding members ( www.uksrilankatrauma.org.uk ). In the first section of the paper, contextual issues will be discussed. The second section of the paper provides details of the training undertaken on mental health promotion among young people in Sri Lanka for the Directorate of Mental Health. The third section of the paper reviews work undertaken with a major psycho-social/mental health organization on issues relating to writing and implementing an ethical code for mental health practitioners and briefly discusses some of the dilemmas associated with this

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

Solar cells based on electrodeposited thin films of ZnS, CdS, CdSSe and CdTe.

The motivations of this research were to produce increased efficiency and low-cost solar cells. The production efficiency of Si solar cells has almost reached their theoretical limit, and reducing the manufacturing cost of Si solar cells is difficult to achieve due to the high-energy usage in material purifying and processing stages. Due to the low usage of materials and input energy, thin film solar cells have the potential to reduce the costs. CdS/CdTe thin film solar cells are already the cheapest on $/W basis. The cost of CdTe solar cells can be further reduced if all the semiconducting layers are fabricated using the electrodeposition (ED) method. ED method is scalable, low in the usage of energy and raw materials. These benefits lead to the cost effective production of semiconductors. The conventional method of fabricating CdS layers produces Cd containing waste solutions routinely, which adds to the cost of solar cells.ZnS, CdS and CdS(i-X)Sex buffer and window layers and CdTe absorber layers have been successfully electrodeposited and explored under this research investigation. These layers were fully characterised using complementary techniques to evaluate the material properties. Photoelectrochemical (PEC) studies, optical absorption, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, atomic force microscopy (AFM) and Raman spectroscopy were utilised to evaluate the material properties of these solid thin film layers. ZnS and CdS thin film layers were electrodeposited from Na-free chemical precursors to avoid the group I element (Na) to reduce deterioration of CdTe devices. Deposition parameters such as, growth substrates, temperature, pH, growth cathodic voltage, stirring rate, time and chemical concentrations were identified to fabricate the above semiconductors. To further optimise these layers, a heat treatment process specific to the material was developed. In addition, the deposition parameters of CdTe layers were further optimised. This research programme has demonstrated that electrodeposited ZnS, CdS and CdTe thin film layers have material characteristics comparable with those of the materials reported in the literature and can be used in thin film solar cell devices. Furthermore, the electrolytes were used for up to two years, reducing the wastage even further, in comparison to other fabrication methods, such as chemical bath deposition. Several large-area semiconducting layers were successfully fabricated to test the scalability of the method. Nano-rods perpendicular to the glass/FTO surface with gaps among grains in CdS layers were observed. In order to reduce the possible pinholes due the gaps, a deposition of a semiconducting layer to cover completely the substrate was investigated. CdS(i-X)Sex layers were investigated to produce a layer-by-layer deposition of the material. However it was observed the surface morphology of CdS(j.X)Sex is a function of the growth parameters which produced nano-wires, nano-tubes and nano-sheets. This is the first recording of this effect for a low temperature deposition method, minimising the cost of producing this highly photosensitive material for use in various nano technology applications.The basic structure experimented was glass/conducting-glass/buffer layer/window material/absorber material/metal. By utilising all the semiconducting layers developed, several solar cell device structures were designed, fabricated and tested. This included a novel all-electrodeposited multi-layer graded bandgap device, to enhance the absorption of solar photons. The device efficiencies varied from batch to batch, and efficiencies in the range (3-7)% were observed. The variations in chemical concentrations, surface states and the presence of pin-hole defects in CdS were the main reasons for the range of efficiencies obtained. In the future work section, ways to avoid these variations and to increase efficiencies are identified and presented

Correlation of microsynteny conservation and disease gene distribution in mammalian genomes

<p>Abstract</p> <p>Background</p> <p>With the completion of the whole genome sequence for many organisms, investigations into genomic structure have revealed that gene distribution is variable, and that genes with similar function or expression are located within clusters. This clustering suggests that there are evolutionary constraints that determine genome architecture. However, as most of the evidence for constraints on genome evolution comes from studies on yeast, it is unclear how much of this prior work can be extrapolated to mammalian genomes. Therefore, in this work we wished to examine the constraints on regions of the mammalian genome containing conserved gene clusters.</p> <p>Results</p> <p>We first identified regions of the mouse genome with microsynteny conservation by comparing gene arrangement in the mouse genome to the human, rat, and dog genomes. We then asked if any particular gene types were found preferentially in conserved regions. We found a significant correlation between conserved microsynteny and the density of mouse orthologs of human disease genes, suggesting that disease genes are clustered in genomic regions of increased microsynteny conservation.</p> <p>Conclusion</p> <p>The correlation between microsynteny conservation and disease gene locations indicates that regions of the mouse genome with microsynteny conservation may contain undiscovered human disease genes. This study not only demonstrates that gene function constrains mammalian genome organization, but also identifies regions of the mouse genome that can be experimentally examined to produce mouse models of human disease.</p

Irrigation and drainage in the new millennium

Presented at the 2000 USCID international conference, Challenges facing irrigation and drainage in the new millennium on June 20-24 in Fort Collins, Colorado.Includes bibliographical references.Climate potential in respect to onset, magnitude and risk associated with rainfall for crop production in the Nilwala basin, Southern Sri Lanka was assessed using the daily rainfall of 12 stations scattered in different locations for more than 35 consecutive years (1950-1995). The program CROPWAT was used to assess the irrigation need. It was revealed that rainfall of the basin increases from south to north with increasing elevation and altitude. Within a 70-km distance in the south north gradient, rainfall elevates from 1656 mm at Kekanadura to 4216 mm at Kudawa. The net irrigation requirement of Yala rice in different locations varied from 1012 mm to 1246 mm. It was established that the irrigation need in the Nilwala upper catchment is below 40 % of the total water requirement, but in downstream areas it constitutes above 70% of the total water demand. Therefore both the Yala and Maha seasons in Nilwala downstream areas appeared to be unsuitable for rice cultivation without supplementary irrigation. From April 10th onward until May 20th is the best period for establishment of perennial crops at upper catchment areas. Optimum dates for crop establishment at the mid and lower part of the catchment falls on the 14th meteorological week. It is important to note that delaying crop establishment in Yala by 2 or 3 weeks from the optimum date would result in a considerable increase of irrigation need even in the upper catchment areas; it is not advisable to delay the establishment of Maha rice until October when rice varieties off our month duration are cultivated

Building Integrated Vegetation Systems and their Sustainability Aspects; A Literature Review

Abstract:There is a growing need of sustainable building development all over the world. It aims to decrease the adverse effects to the environment due to urbanization and escalating population growth. Since the building construction is considered as one of the main concerns, the priority was given to mitigate the negative impact to the environment. Therefore, incorporating sustainable elements and techniques to the buildings to regain the land loss due to construction activities in cities is currently practicing. Adding various vegetation types through different approaches, to obtain the expected results of better living condition around the building is called as building integrated vegetation systems (BIV). Vertical gardening systems, vertical farms, constructed green roofs and roof farms can be stated as main categories of BIV systems. However, there is a paucity of published critical reviews on such systems and therefore, this study is an attempt to review the overall sustainability aspects of BIV systems including environmental sustainability, economic sustainability and social sustainability. This study consists with a critical review of 114 research publications from relevant journals and online scientific databases. Finally, the identified sustainability aspects of each BIV systems were analyzed to select the best option in terms of greening a building which can be recommended for the implementations in future. Mainly, the importance of moving towards the sustainable solution which meets the food needs through BIV is finally discussed. Finally, it can be concluded that by incorporating green architecture with smart agriculture, we can expect green, healthy and productive cities which fulfill the main requirements of sustainable cities. Though there are many challenges to overcome, maintaining good management practices will give better output. Out of the 114 literature selected for this study, only 8 research papers were discussed about the drawbacks and the limitations of the BIV systems which is still having paucity of information. Keywords: Building Integrated Vegetation systems, Economic Sustainability, Environmental Sustainability, Social Sustainabilit

Predicting the effects of deep brain stimulation using a reduced coupled oscillator model

This is the final version. Available on open access from Public Library of Science via the DOI in this recordData Availability: The data analysed in this manuscript is available from MRC BNDU Data Sharing platform at: https://data.mrc.ox.ac.uk/data-set/tremor-data-measured-essential-tremor-patients-subjected-phase-locked-deep-brain DOI: 10.5287/bodleian:xq24eN2KmDeep brain stimulation (DBS) is known to be an effective treatment for a variety of neurological disorders, including Parkinson’s disease and essential tremor (ET). At present, it involves administering a train of pulses with constant frequency via electrodes implanted into the brain. New ‘closed-loop’ approaches involve delivering stimulation according to the ongoing symptoms or brain activity and have the potential to provide improvements in terms of efficiency, efficacy and reduction of side effects. The success of closed-loop DBS depends on being able to devise a stimulation strategy that minimizes oscillations in neural activity associated with symptoms of motor disorders. A useful stepping stone towards this is to construct a mathematical model, which can describe how the brain oscillations should change when stimulation is applied at a particular state of the system. Our work focuses on the use of coupled oscillators to represent neurons in areas generating pathological oscillations. Using a reduced form of the Kuramoto model, we analyse how a patient should respond to stimulation when neural oscillations have a given phase and amplitude, provided a number of conditions are satisfied. For such patients, we predict that the best stimulation strategy should be phase specific but also that stimulation should have a greater effect if applied when the amplitude of brain oscillations is lower. We compare this surprising prediction with data obtained from ET patients. In light of our predictions, we also propose a new hybrid strategy which effectively combines two of the closed-loop strategies found in the literature, namely phase-locked and adaptive DBS