The Costs and Cost-Effectiveness of Mass Treatment for Intestinal Nematode Worm Infections Using Different Treatment Thresholds

Almost one in every two people in the developing world is infected with one or more types of intestinal nematode worms. When fewer than 50% of people are infected, most carry only a few worms; but when more than 50% are infected, the number carrying moderate to heavy numbers increases markedly, as does the risk of disease. The WHO recommends annual mass deworming of children when 20% or more are infected and twice a year if 50% or more are infected. We estimated the cost of this to treat children with 10+ worms, an arbitrary moderate to heavy infection. We concluded that it is not cost-effective to mass treat children when fewer than 40% are infected because the majority are uninfected and few are likely be diseased. We propose annual treatment when 40% or more children are infected, twice a year at 60%, and three times a year at 80% or more. This would cost USD 224 million annually to treat all children aged 2–14 years in 107 developing countries compared with USD 276 million using current WHO guidelines. The new three-tier guidelines also treat a larger proportion of infected children and treat children with moderate to heavy worm burdens more often

The Left-Right SU(3)(L)xSU(3)(R)xU(1)(X) Model with Light, keV and Heavy Neutrinos

We construct a full left-right model for the electroweak interactions based on the $SU(3)_{L}\otimes SU(3)_{R}\otimes U(1)_{X}$ gauge symmetry. The fermion content of the model is such that anomaly cancellation restricts the number of families to be a multiple of three. One of the most important features of the model is the joint presence of three light active neutrinos, three additional neutrinos at keV mass scale, and six heavy ones with masses around\textbf{$10^{11}$} GeV. They form a well-motivated part of the spectrum in the sense they address challenging problems related to neutrino oscillation, warm dark matter, and baryogenesis through leptogenesis.Comment: 11 pages. Small corrections and typos fixed. Accepted for publication in PR

Spin-1 Particles with Light-Front Approach

For the vector sector, i.e, mesons with spin-1, the electromagnetic form factors and anothers observables are calculated with the light-front approach. However, the light-front quantum field theory have some problems, for example, the rotational symmetry breaking. We solve that problem added the zero modes contribuition to the matrix elements of the electromagnetic current, besides the valence contribuition. We found that among the four independent matrix elements of the plus component in the light-front helicity basis only the $0\to 0$ one carries zero mode contributions.Comment: 5 pages. 3 Figures, use latex and EPJ styl

Native forest (Caatinga) watershed management for runoff in ducement for irrigation.

The results of hydrological investigations for two years on eight levels of native forest (Caatinga) watershed management, principally for runoff inducement for water harvesting for irrigation, are reported. The first four watershed treatments consisted of one or a combination of intensified surface drainage treatments wthing native forest watershed, clearing alternate contour strips of native forest at 250cm vertical intervals shile alternate strips are maintained in native cover, constructing narrow-based channel terraces below cleared strips and application of common slat in cleared strips for impermeabilization of the soil. The next three watershed treatments are without native forest and the eighth (the last) watershed is maintained undisturbed under native forest cover as a control treatment. In the arid zones of the Northeast of Brazil, the combination of (i) clearing alternate strips of Caatinga with alternate virgin strips about 30 m wide at 25-cm vertical interval on gently sloped watersheds and (ii) the construction of narrow based channel terraces, can make available for irrigation about- 5-11% of the incident rainfall. At the same time this combination helps conserve soil and natural forest ecosystems

Household water security through stored rainwater and consumer acceptability: a case study of the Anuradhapura District

Rainwater harvesting has increased in popularity in Sri Lanka over the past two decades due to the number of water supply projects funded by the government and non-governmental organizations (NGOs). The stored rainwater can provide accessible, reliable, timely and adequate supplies of water to households but there are uncertainties as to safety, in terms of water quality, and consumer acceptability. A study was, therefore, conducted in the Anuradhapura District, in the dry zone, to assess consumer acceptability of stored rainwater for household purposes and to conduct rainwater quality tests in a laboratory. The majority of households in Anuradhapura meet their drinking water requirements from protected wells (59.6 %). Prior to the project, people greatly preferred open wells as a source of domestic water, followed by tubewells, because they believed that water in open wells is of good quality and drinkable. However, stored rainwater has become the priority source now, especially through roof rainwater harvesting (RRWH), which is used during the dry periods. The study revealed that more than 85 % of households use stored rainwater for drinking although some have concerns over the quality and only drink it after boiling. The easy accessibility of water and the assurance by the project team that it is of good quality are the main reasons that people are willing to drink it. The acceptability of stored rainwater for consumption was very high in water-scarce areas and with the increasing distance to the nearest and alternative sources of good-quality water. Of those who felt that they had adequate water, 84 % of the sample households found it adequate in the wet season but only 21 % in the dry season. Water quality analysis revealed that the chemical and physical quality of stored rainwater is within the acceptable range with respect to Sri Lankan Standards, SLS: 614, for potable water quality (SLIS 1983). Other domestic water sources exceeded standards for electrical conductivity, total alkalinity, hardness, ammonium nitrogen, fluorides and total iron. However, stored rainwater was of lower biological quality than other domestic water sources.Length: pp.87-97Domestic waterWater securityWater harvestingWater qualityRural areasCase studies

Neutrino Decay and Neutrinoless Double Beta Decay in a 3-3-1 Model

In this work we show that the implementation of spontaneous breaking of the lepton number in the 3-3-1 model with right-handed neutrinos gives rise to fast neutrino decay with majoron emission and generates a bunch of new contributions to the neutrinoless double beta decay.Comment: Version accepted for publication in the Phys. Rev.