ECO FRIENDLY SEWERAGE SYSTEM FOR A LOW INCOME COASTAL COMMUNITY

The purpose of a sewerage disposal system is to carry human excreta & urine (Black water) and wastewater (Gray water) back to nature in a proper way without any harm to the environment as well as to human beings. But the implementing and operating costs of the sewerage disposal systems are normally very high which make low income communities unable to access these techniques. The aim of this study was to find a proper sewerage system for a low income coastal community, “Pittaniya Watta” in Moratuwa Municipal Council. The community consists of 142 families with about 710 people spreading over a 5051m2 limited area. At first the real situation and the problems prevailing were found  through a questionnaire survey considering a proper cross section. Questionnaires were analyzed and evaluated and daily water consumption, sewerage disposal capacities, communicannt’s desire were found. Finally Eco-sanitation units and simplified sewerage system were selected as the most economical solutions for the problem.Number of Eco-sanitation units required for the said community was 142. The simplified sewerage system (“off-site disposal system”) was designed considering both self cleansing velocity (0.5 m/s) as well as tractive tension (1 Pa). The results revealed that the best fitted minimum sewer gradient and the minimum sewer diameter were 1 in 208 and 100mm respectively. The collected sewage will be treated in primary and secondary stages in anaerobic digestion units. Three units were provided with each dimension length, width and depth of 6.2mx 3mx4m respectively and 0.2 m of free board. Using a lift station a head was added to the effluent to take it from 5m below the ground to the ground surface where the Reed bed was provided before it is released to the existing drains that are directed to the sea. Estimated hydraulic retention time of the reed bed is 6.79 hours while dimensions are water depth = 0.6m and surface area of the bed=78m2. According to the basic cost analysis on two systems Eco-san unit for each house is Rs 47925. When considering the whole community, the total cost for Eco-san was Rs 6,805,350 while the simplified sewerage system was Rs 2,886,000. However, at the operational stage of simplified sewerage system, with maintenance cost, the total cost was estimated as Rs 16,606,390.00. Therefore, based on the cost the most suitable system for the subjected community is Eco-san. But according to communicant’s desire, land scarcity, and population growth as well as future forecast on water consumption, improvement of the living standards etc. simplified sewerage system was selected as the best sewerage disposal system to implement at Pitaniya Watta low income community

Weak charge form factor and radius of 208Pb through parity violation in electron scattering

We use distorted wave electron scattering calculations to extract the weak charge form factor F_W(q), the weak charge radius R_W, and the point neutron radius R_n, of 208Pb from the PREX parity violating asymmetry measurement. The form factor is the Fourier transform of the weak charge density at the average momentum transfer q=0.475 fm$^{-1}$. We find F_W(q) =0.204 \pm 0.028 (exp) \pm 0.001 (model). We use the Helm model to infer the weak radius from F_W(q). We find R_W= 5.826 \pm 0.181 (exp) \pm 0.027 (model) fm. Here the exp error includes PREX statistical and systematic errors, while the model error describes the uncertainty in R_W from uncertainties in the surface thickness \sigma of the weak charge density. The weak radius is larger than the charge radius, implying a "weak charge skin" where the surface region is relatively enriched in weak charges compared to (electromagnetic) charges. We extract the point neutron radius R_n=5.751 \pm 0.175 (exp) \pm 0.026 (model) \pm 0.005 (strange) fm$, from R_W. Here there is only a very small error (strange) from possible strange quark contributions. We find R_n to be slightly smaller than R_W because of the nucleon's size. Finally, we find a neutron skin thickness of R_n-R_p=0.302\pm 0.175 (exp) \pm 0.026 (model) \pm 0.005 (strange) fm, where R_p is the point proton radius.Comment: 5 pages, 1 figure, published in Phys Rev. C. Only one change in this version: we have added one author, also to metadat

Moments of the neutron g2g_2 structure function at intermediate Q2Q^2

We present new experimental results of the $^3$He spin structure function $g_2$ in the resonance region at $Q^2$ values between 1.2 and 3.0 (GeV/c)$^2$. Spin dependent moments of the neutron were then extracted. Our main result, the resonance contribution to the neutron $d_2$ matrix element, was found to be small at $$=2.4 (GeV/c)$^2$ and in agreement with the Lattice QCD calculation. The Burkhardt-Cottingham sum rule for $^3$He and the neutron was tested with the measured data and using the Wandzura-Wilczek relation for the low $x$ unmeasured region. A small deviation was observed at $Q^2$ values between 0.5 and 1.2 (GeV/c)$^2$ for the neutron

Polarization transfer in the d(epol,e' ppol)n reaction up to Q^2=1.61 (GeV/c)^2

The recoil proton polarization was measured in the d(epol,e' ppol)n reaction in Hall A of the Thomas Jefferson National Accelerator Facility (JLab). The electron kinematics were centered on the quasielastic peak (x_{Bj}~1) and included three values of the squared four-momentum transfer, Q^2=0.43, 1.00 and 1.61 (GeV/c)^2. For Q^2=0.43 and 1.61 (GeV/c)^2, the missing momentum, p_m, was centered at zero while for Q^2=1.00 (GeV/c)^2 two values of p_m were chosen: 0 and 174 MeV/c. At low p_m, the Q^2 dependence of the longitudinal polarization, P_z', is not well described by a state-of-the-art calculation. Further, at higher p_m, a 3.5 sigma discrepancy was observed in the transverse polarization, P_x'. Understanding the origin of these discrepancies is important in order to confidently extract the neutron electric form factor from the analogous d(epol,e' npol)p experiment.Comment: 6 pages, 4 figures; updated text, figures and table

Quark-Hadron Duality in Neutron (3He) Spin Structure

We present experimental results of the first high-precision test of quark-hadron duality in the spin-structure function g_1 of the neutron and $^3$He using a polarized 3He target in the four-momentum-transfer-squared range from 0.7 to 4.0 (GeV/c)^2. Global duality is observed for the spin-structure function g_1 down to at least Q^2 = 1.8 (GeV/c)^2 in both targets. We have also formed the photon-nucleon asymmetry A_1 in the resonance region for 3He and found no strong Q^2-dependence above 2.2 (GeV/c)^2.Comment: 13 pages, 3 figure

Cross Section Measurement of Charged Pion Photoproduction from Hydrogen and Deuterium

We have measured the differential cross section for the gamma n --> pi- p and gamma p --> pi+ n reactions at center of mass angle of 90 degree in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). The data at photon energies greater than 3.3 GeV exhibit a global scaling behavior for both pi- and pi+ photoproduction, consistent with the constituent counting rule and the existing pi+ photoproduction data. Possible oscillations around the scaling value are suggested by these new data The data show enhancement in the scaled cross section at a center-of-mass energy near 2.2 GeV. The cross section ratio of exclusive pi- to pi+ photoproduction at high energy is consistent with the prediction based on one-hard-gluon-exchange diagrams

Stigma associated with cutaneous leishmaniasis in rural Sri Lanka: development of a conceptual framework

Background: There is limited knowledge about the stigma associated with cutaneous leishmaniasis (CL) in Sri Lanka. To ensure that leishmaniasis researchers focus on CL-associated stigma, we provide an evidence-based framework that can be used in future research. Methods: We conducted a systematic review on CL-associated stigma using international evidence and carried out a multimethod qualitative study in the Anuradhapura district in Sri Lanka. Based on that, we identified manifestations of stigma, drivers and facilitators that we synthesised to develop a conceptual framework on CL-associated stigma. Results: Our framework consists of drivers, facilitators and self-stigma experienced by people with CL. Stigma drivers included fear, misbeliefs and misconceptions about CL; the belief that wounds are disfiguring; the treatment burden and implied blame. Facilitators that reduced stigma included knowledge of the curability of CL and awareness that CL is not contagious. The nature of social interactions in rural communities enhanced stigma formation. We identified various enacted, felt and internalised stigma experiences of people with CL. Conclusions: We developed a conceptual framework of the stigma associated with CL that can be used to develop targeted interventions to increase CL awareness, address stigma and improve the quality of life for CL patients