Laser Spectroscopy for Atmospheric and Environmental Sensing

Lasers and laser spectroscopic techniques have been extensively used in several applications since their advent, and the subject has been reviewed extensively in the last several decades. This review is focused on three areas of laser spectroscopic applications in atmospheric and environmental sensing; namely laser-induced fluorescence (LIF), cavity ring-down spectroscopy (CRDS), and photoluminescence (PL) techniques used in the detection of solids, liquids, aerosols, trace gases, and volatile organic compounds (VOCs)

Holistic assessment of sustainable urban development

Introducing the SUE-MoT (metrics, models and toolkits for whole-life sustainable urban development) series, this paper highlights some of the barriers that need to be addressed if the vision for holistic assessment is to be realised. The complexities of sustainability assessment raised in this paper will be further discussed in detail in the SUE-MoT series of papers that will be published in forthcoming issues of this journal. This paper highlights the priorities to address when assessment tools are presented to decision makers of urban development projects. This discussion is limited to the issues, values and solutions in the UK context

A Comparison of Miltefosine and Sodium Stibogluconate for Treatment of Visceral Leishmaniasis in an Ethiopian Population with High Prevalence of HIV Infection.

BACKGROUND: Antimonials are the mainstay of visceral leishmaniasis (VL) treatment in Africa. The increasing incidence of human immunodeficiency virus (HIV) coinfection requires alternative safe and effective drug regimens. Oral miltefosine has been proven to be safe and effective in the treatment of Indian VL but has not been studied in Africa or in persons with HIV and VL coinfection. METHODS: We compared the efficacy of miltefosine and sodium stibogluconate (SSG) in the treatment of VL in persons in Ethiopia. A total of 580 men with parasitologically and/or serologically confirmed VL were randomized to receive either oral miltefosine (100 mg per day for 28 days) or intramuscular SSG (20 mg/kg per day for 30 days). RESULTS: The initial cure rate was 88% in both treatment groups. Mortality during treatment was 2% in the miltefosine group, compared with 10% in the SSG group. Initial treatment failure was 8% in the miltefosine group, compared with 1% in the SSG group. Among the 375 patients (65%) who agreed to HIV testing, HIV seroprevalence was 29%. Among patients not infected with HIV, initial cure, mortality, and initial treatment failure rates were not significantly different (94% vs. 95%, 1% vs. 3%, and 5% vs. 1% for the miltefosine and SSG groups, respectively). Initial treatment failure with miltefosine occurred in 18% of HIV-coinfected patients, compared with treatment failure in 5% of non-HIV-infected patients. At 6 months after treatment, 174 (60%) of the 290 miltefosine recipients and 189 (65%) of the 290 SSG recipients experienced cure; 30 (10%) of 290 in the miltefosine group and 7 (2%) of 290 in the SSG group experienced relapse, and the mortality rate was 6% in the miltefosine group, compared with 12% in the SSG group. HIV-infected patients had higher rates of relapse (16 [25%] of 63 patients), compared with non-HIV-infected patients (5 [5%] of 131). CONCLUSIONS: Treatment with miltefosine is equally effective as standard SSG treatment in non-HIV-infected men with VL. Among HIV-coinfected patients, miltefosine is safer but less effective than SSG

Arresting gully formation in the Ethiopian highlands

Over the past five decades, gullying has been widespread and has become more severe in the Ethiopian highlands. Only in very few cases, rehabilitation of gullies has been successful in Ethiopia due to the high costs. The objective of this paper is to introduce cost effective measures to arrest gully formation. The research was conducted in the Debre-Mewi watershed located at 30 km south of Bahir Dar, Ethiopia. Gullying started in the 1980s following the clearance of indigenous vegetation and intensive agricultural cultivation, leading to an increase of surface and subsurface runoff from the hillside to the valley bottoms. Gully erosion rates were 10–20 times the measured upland soil losses. Water levels, measured with piezometers, showed that in the actively eroding sections, the water table was in general above the gully bottom and below it in the stabilized sections. In order to develop effective gully stabilizing measures, we tested and then applied the BSTEM and CONCEPT models for their applicability for Ethiopian conditions where active gully formation has been occurring. We found that the model predicted the location of slips and slumps well with the observed groundwater depth and vegetation characteristics. The validated models indicated that any gully rehabilitation project should first stabilize the head cuts. This can be achieved by regrading these head cuts to slope of 40 degrees and armoring it with rock. Head cuts will otherwise move uphill in time and destroy any improvements. To stabilize side walls in areas with seeps, grass will be effective in shallow gullies, while deeper gullies require reshaping of the gullies walls, then planting the gully with grasses, eucalyptus or fruit trees that can be used for income generation. Only then there is an incentive for local farmers to maintain the structures

[Evaluation of malaria rapid diagnostic test Optimal-IT® pLDH along the Plasmodium falciparum distribution limit in Mauritania].

Performance of the malaria Rapid Diagnostic Test (RDT) OptiMal-IT® was evaluated in Mauritania where malaria is low and dependent on a short transmission season. Slide microscopy was considered as the reference method of diagnosis. Febrile patients with suspected malaria were recruited from six health facilities, 3 urban and 3 rural, during two periods (December 2011 to February 2012, and August 2012 to March 2013). Overall, 780 patients were sampled, with RDT and thick blood film microscopy results being obtained for 759 of them. Out of 774 slides examined, of which 200 were positive, P. falciparum and P. vivax mono-infections were detected in 63.5% (127) and 29.5% (59), while P. falciparum/P. vivax coinfections were detected in 7% (14). Both species were observed in all study sites, although in significantly different proportions. The proportions of thick blood film and OptiMal-IT® RDT positive individuals was 26.3% and 30.3% respectively. Sensitivity and specificity of OptiMal-IT® RDT were 89% [95% CI, 84.7-93.3] and 91.1% [88.6-93.4]. Positives and negative predictive values were 78.1% [72.2-83.7] and 95.9% [94.1-97.5]. These diagnostic values are similar to those generally reported elsewhere, and support the use of RDTs as the main diagnostic tool for malaria in Mauritanian health facilities. In the future, choice of RDTs to be used must take account of thermostability in a hot, dry environment and their ability to detect P. falciparum and P. vivax

Farmer experience of pluralistic agricultural extension, Malawi

Purpose: Malawi’s current extension policy supports pluralism and advocates responsiveness to farmer demand. We investigate whether smallholder farmers’ experience supports the assumption that access to multiple service providers leads to extension and advisory services that respond to the needs of farmers. Design/methodology/approach: Within a case study approach, two villages were purposively selected for in-depth qualitative analysis of available services and farmers’ experiences. Focus group discussions were held separately with male and female farmers in each village, followed by semi-structured interviews with 12 key informants selected through snowball sampling. Transcripts were analysed by themes and summaries of themes were made from cross case analysis. Findings: Farmers appreciate having access to a variety of sources of technical advice and enterprise specific technology. However, most service providers continue to dominate and dictate what they will offer. Market access remains a challenge, as providers still emphasize pushing a particular technology to increase farm productivity rather than addressing farmers’ expressed needs. Although farmers work in groups, providers do not seek to strengthen these to enable active interaction and to link them to input and produce markets. This limits farmers’ capacity to continue with innovations after service providers pull out. Poor coordination between providers limits exploitation of potential synergies amongst actors. Practical implications: Services providers can adapt their approach to engage farmers in discussion of their needs and work collaboratively to address them. At a system level, institutions that have a coordination function can play a more dynamic role in brokering interaction between providers and farmers to ensure coverage and responsiveness. Originality/value: The study provides a new farmer perspective on the implementation of extension reforms