The durability of long-lasting insecticidal nets distributed to the households between 2009 and 2013 in Nepal

Background: Understanding and improving the durability of long-lasting insecticidal nets (LLINs) in the field are critical for planning future implementation strategies including behavioral change for care and maintenance. LLIN distribution at high coverage is considered to be one of the adjunctive transmission reduction strategies in Nepal’s Malaria Strategic Plan 2014–2025. The main objective of this study was to assess the durability through assessment of community usage, physical integrity, residual bio-efficacy, and chemical retention in LLINs: Interceptor®, Yorkool®, and PermaNet ®2.0 which were used in Nepal during 2009 through 2013. Methods: Assessments were conducted on random samples (n = 440) of LLINs from the eleven districts representing four ecological zones: Terai plain region (Kailali and Kanchanpur districts), outer Terai fluvial ecosystem (Surkhet, Dang, and Rupandhei districts), inner Terai forest ecosystem (Mahhothari, Dhanusa, and Illam districts), and Hills and river valley (Kavrepalanchock and Sindhupalchok districts). For each LLIN, fabric integrity in terms of proportionate hole index (pHI) and residual bio-efficacy were assessed. However, for chemical retention, a representative sample of 44 nets (15 Yorkool®, 10 Permanet®2.0, and 19 Interceptor®) was evaluated. Data were analyzed using descriptive statistics stratified by LLINs brand, districts, and duration of exposure. Results: On average, duration of use of LLINs was shortest for the Yorkool® samples, followed by PermaNet® 2.0 and Interceptor® with median ages of 8.9 (IQR = 0.4), 23.8 (IQR = 3.2), and 50.1 (IQR = 3.2) months, respectively. Over 80% of field distributed Yorkool® and PermaNet® 2.0 nets were in good condition (pHI< 25) compared to Interceptor® (66%). Bio-efficacy analysis showed that average mortality rates of Interceptor and Yorkool were below World Health Organization (WHO) optimal effectiveness of ≥ 80% compared to 2-year-old PermaNet 2.0 which attained 80%. Chemical retention analysis was consistent with bio-efficacy results. Conclusion: This study shows that distribution of LLINs is effective for malaria control; however, serviceable life of LLINs should be considered in terms of waning residual bio-efficacy that warrants replacement. As an adjunctive malaria control tool, National Malaria Control Program of Nepal can benefit by renewing the distribution of LLINs in an appropriate time frame in addition to utilizing durable and effective LLINs

Development of Regional Individual Tree Static Equations for Managed Mixed Species Stands of the Acadian Region of North America

The Forest Vegetation Simulator northeast variant (FVS-NE) is a commonly used growth and yield model for sustainable forest management in the Acadian Region of North America. This region encompasses three Atlantic Provinces of Canada (New Brunswick, Nova Scotia, and Prince Edward Island), the southern part of Quebec, and Maine in the USA. This geographical area consists of diverse vegetation types, naturally regenerated stands, and has a long history of forest management. Earlier studies have shown that FVS-NE produces biased predictions for permanent research plot data (e.g. Saunders et al., 2007). Consequently, the Cooperative Forest Research unit (CFRU) of the University of Maine has identified the need to reengineer the regional growth and yield model. In addition, there are extensive data available that has been collected by different sources such as US Forest Service Forest Inventory and Analysis (FIA), CFRU, and other USFS research installations. Besides, statistical techniques and computational abilities have vastly improved since the original FVS models were developed. Regional models to predict total height (H-D; Chapter 3) and height to crown base (HCB; Chapter 4) were constructed using an extensive database. Several candidate models were evaluated including the ones currently used by FVS. General nonlinear least squares (GNLS) and hierarchical nonlinear mixed effects (NLME) techniques were used for model fits and predictions. Different model selection criteria (MSC) were used to select the best among the candidate models. Coefficients of Determination (R ), Akaike Information Criteria (AIC) and Bayesian Information Criteria (BIC) were used as MSC for model fits, while mean absolute bias (MAB), mean bias (MB), root mean square error (RMSE), and percent error were used as MSC prediction statistics. Bootstrap technique was utilized to construct non-parametric confidence intervals (CI) of the MSC prediction. Models were evaluated at 5% significance level based on 95% CI of these criteria. Several individual- and stand-level allometric, competition, and site related covariates were evaluated. For the H-D models, the Chapman-Richards (C-R) model form was found to be superior to the FVS-NE model form for all MSC. For example, RMSE and MB were reduced by 67% and 99%, respectively, when FVS-NE was compared to the C-R models. Likewise, findings for the HCB model indicated that FVS-NE model was significantly biased for all species as the overall MB and RMSE were 0.1 lm (significant at 5%) andl.80m, respectively. A logistic equation with size (tree diameter at breast height (DBH), total height (HT), ratio of DBH to HT (DHR)) and competition (crown competition factor (CCF) and basal area larger than subject tree (BAL)) gave the best predictions for all of the species in this analysis. This model yielded an overall mean bias and RMSE of \u3c0.01m (insignificant at 5%) and 1.59m, respectively, which represents a significant improvement in predictions compared to FVS-NE. In conclusion, the C-R and Richards models were the best among the tested models for H-D and HCB modeling, respectively. Among the various allometric, competition, and site related model covariates evaluated, DBH, CCF, BAL, and climatic site index (CSI) were the most effective in explaining variation in observed HT. Likewise, DBH, DHR, CCF and BAL were the best covariates for predicting HCB. Overall, this study has important implications for imputing missing HTs and HCBs, which is necessary for developing an effective growth and yield modeling system for the Acadian Region

A forest management decision support system for sustainable management of flammable boreal forest landscapes : an integrated policy approach to timber harvest planning

Les feux sont un phénomène naturel dans la forêt boréale du Canada. Ils sont étroitement liés à la croissance et au développement de cet écosystème. Cependant, l’augmentation des activités anthropiques associées au changement climatique graduel peuvent provoquer un accroissement des épisodes de feux. Un tel accroissement pourrait avoir des effets indési-rables sur l'industrie forestière en raison d’une rupture de l'approvisionnement en bois sur une période de planification à long terme. Cette thèse explore une approche alternative pour concevoir des stratégies qui réduiront l'impact potentiel des feux de forêt sur les revenus à long terme générés par la vente de produits forestiers ciblés, et ce, au moyen d’une politique d’aménagement forestier spécifique. L'étude est basée sur les données de trois unités d’aménagement forestier localisées dans la région boréale de la province de Québec au Ca-nada. Les modèles de politique de planification de la récolte forestière ont été résolus en utilisant la programmation linéaire intégrée avec un taux de brûlage constant. Les options de récolte prescrites par les modèles de planification ont été évaluées à l’aide d’un modèle de simulation de paysage intégré avec un taux de brûlage stochastique. Parmi les quatre modèles pris en compte, le modèle verticalement intégré (modèle 4) a géné-ré les revenus les plus élevés tout en ayant les variations les moins importantes de revenu au sein et entre les périodes pour l'horizon de planification. Ce modèle a permis de maximiser la valeur actuelle nette des recettes provenant de la vente de produits de première transfor-mation pour les deux premières périodes soumis à une récolte forestière constante et à des volumes de bois récupérés durant une période de planification complète. Les revenus plus élevés et les variations plus faibles suggèrent que le modèle peut réduire le risque des im-pacts des feux de forêt sur les revenus comparativement aux trois autres modèles, y compris le modèle de rendement soutenu qui maximise le volume de la récolte soumis à des flux constants du volume de récolte durant une période de planification (modèle 1). L'analyse des dépenses de gestion des incendies a démontré que l’augmentation de telles dépenses peut réduire le coût de lutte contre les feux et augmenter les revenus de la récolte tout en diminuant la variabilité. Cependant, il y a un niveau optimal de dépense qui dépend de la structure forestière et des régimes de feux. Par conséquent, une répartition optimale des dépenses de prévention peut réduire le risque d'impact du feu sur l’économie forestière à long terme. La pérennité des écosystèmes est importante en gestion forestière. Par conséquent, l'intégri-té écologique est de plus en plus préoccupante en ce qui concerne les forêts publiques cana-diennes qui sont aménagées à des fins commerciales. La mise en œuvre d’une politique de récolte exigeant la conservation des vieilles forêts tout en tenant compte de l'impact poten-tiel du feu peut avoir des effets négatifs sur les revenus. Les impacts peuvent être réduits en choisissant une politique de gestion forestière alternative. La réduction des revenus à court terme peut être compensée par des retours à long terme générés par la valeur ajoutée asso-ciée à l'âge du bois en utilisant des politiques alternatives. Finalement, les résultats démontrent que le modèle de planification de la récolte intégrée verticalement et l’optimisation des efforts de gestion du feu peuvent accroître les revenus à moyen et à long terme de l'industrie forestière. Le modèle réduit le risque de perte de reve-nus lié à la rupture de l'approvisionnement lorsque l'impact du feu est inclus dans le proces-sus de planification. De plus, les solutions prescrites dans ce modèle aident à réduire le taux de récolte et à augmenter le volume des stocks qui peut être un coussin en prévision des feux qui surviennent de façon très variable au cours des périodes de l’horizon de planification.Forest fire is a natural process in the boreal forest region of Canada and it is strongly con-nected to forest growth and development. Yet, increasing anthropogenic activities coupled with gradual climate change can increase fire occurrence and area burned. Such an increase may cause adverse impacts on the forest-based economy by the potential disruption of tim-ber supply over a long-term planning horizon. This thesis explores an alternative approach to designing strategies to reduce the potential impact of fire on long-term revenues generated by the sale of prescribed harvest products using a specified forest management policy. The study is based on data from three commercially-managed forests located in the boreal forest region of the province of Quebec, Canada. The harvest planning policy models were solved using a constant average annual burn rate-embedded in a linear programming model. The harvest solutions prescribed by the planning model were evaluated by implementing them in a stochastic landscape simulation model. Among the four policy models examined, vertically integrated model (model 4) generated the highest revenue with the least within- and among-period variation in revenue over the planning horizon. This model maximized the net present value from the sale of primary-processed wood products for the first two periods subjecting to the constant flows of har-vest timber and recovered lumber volumes for an entire planning horizon. The higher reve-nue and lower variation suggest that the model can have lower risk of fire impacts on reve-nue compared with the other three models including the status quo sustained-yield policy model (model 1) that maximizes harvest timber volume subject to constant flows of the harvest volume over the planning horizon. Analysis of fire management expenditures demonstrated that increased presuppression ex-penditure can reduce suppression costs and increase the revenue from the harvest while lowering the variability. However, there is an optimal level of expenditure, which depends on the structure of the forest and fire regimes. Hence, an optimal allocation of presuppres-sion expenditure can reduce the risk of the fire on the long-term economics of the forest. Ecosystem sustainability is important for forest management. Therefore, ecological integrity is of increasing concern with respect to commercially-managed public forests in Canada. Implementation of a harvest policy with strict requirement of old-growth forest area con-straint while accounting for the possible impact of fire can have adverse impacts on reve-nue. The impacts can be reduced by selecting alternative forest management policies. The short-term reduction in revenue from harvests can be compensated for by long-term eco-nomic returns provided by age-related value accumulation of the harvest timber using alter-native policies. Finally, based on the results, the vertically integrated harvest planning model coupled with optimal fire management efforts can increase long-term average revenue to wood industry. The model lowers the risk of loss of revenue due to supply disruptions when the impact of fire is accounted for in the planning process. In addition, the solutions prescribed by this model help reduce the harvest rate and increase stock volume which can act as a buffer for the highly variable potential fires in the successive periods over a planning horizon

Integrating Analytical Hierarchical Process and Network Optimization Model to Support Decision-Making on Biomass Terminal Selection

Forest biomass is an appealing bioenergy feedstock due its renewability, availability and potential to stimulate local economies. It is, however, voluminous, with heterogenous fuel characteristics and uncertainties in its supply. The feasibility of a bioenergy facility is contingent on a secure supply of uniform feedstock; a terminal in the supply chain can be useful in this regard. Biomass can be treated in the terminal to meet quality specifications and stored to overcome seasonality and supply disruptions. Nonetheless, such terminals require a significant capital investment; thus, the decision to use a terminal needs to be made judiciously. The decision process must account for a diverse set of factors that influence the terminal’s effectiveness. These include both quantitative and qualitative factors. The objective of this study is to develop a multi-criteria decision-making framework that takes quantitative and qualitative factors into consideration while selecting a terminal. The framework consists of analytical hierarchy process to analyze qualitative information, and a mixed-integer programming model to evaluate quantitative information including fuel quality (moisture content and thermal value). This hybrid framework was implemented in a case study. It proved to be an effective tool for identifying terminals with the highest potential to generate value for the bioenergy supply chain

Glucose-6-phosphate dehydrogenase deficiency in people living in malaria endemic districts of Nepal

Abstract Background Glucose-6-phosphate dehydrogenase (G6PD) is a rate limiting enzyme of the pentose phosphate pathway and is closely associated with the haemolytic disorders among patients receiving anti-malarial drugs, such as primaquine. G6PD deficiency (G6PDd) is an impending factor for radical treatment of malaria which affects the clearance of gametocytes from the blood and subsequent delay in the achievement of malaria elimination. The main objective of this study was to assess the prevalence of G6PD deficiency in six malaria endemic districts in Southern Nepal. Methods A cross-sectional population based prevalence survey was conducted in six malaria endemic districts of Nepal, during April–Dec 2013. A total of 1341 blood samples were tested for G6PDd using two different rapid diagnostic test kits (Binax-Now® and Care Start™). Equal proportions of participants from each district (n ≥ 200) were enrolled considering ethnic and demographic representation of the population groups. Results Out of total 1341 blood specimens collected from six districts, the overall prevalence of G6PDd was 97/1341; 7.23% on Binax Now and 81/1341; 6.0% on Care Start test. Higher prevalence was observed in male than females [Binax Now: male 10.2%; 53/521 versus female 5.4%; 44/820 (p = 0.003) and Care Start: male 8.4%; 44/521 versus female 4.5%; 37/820 (p = 0.003)]. G6PDd was higher in ethnic groups Rajbanshi (11.7%; 19/162) and Tharu (5.6%; 56/1005) (p = 0.006), major inhabitant of the endemic districts. Higher prevalence of G6PDd was found in Jhapa (22/224; 9.8%) and Morang districts (18/225; 8%) (p = 0.031). In a multivariate analysis, male were found at more risk for G6PDd than females, on Binax test (aOR = 1.97; CI 1.28–3.03; p = 0.002) and Care Start test (aOR = 1.86; CI 1.16–2.97; p = 0.009). Conclusions The higher prevalence of G6PDd in certain ethnic group, gender and geographical region clearly demonstrates clustering of the cases and ascertained the risk groups within the population. This is the first study in Nepal which identified the vulnerable population groups for G6PDd in malaria endemic districts. The finding of this study warrants the need for G6PDd testing in vulnerable population groups in endemic districts, and also facilitates use of primaquine in mass supporting timely progress for malaria elimination

Transmission of <i>Leishmania donovani</i> in the Hills of Eastern Nepal, an Outbreak Investigation in Okhaldhunga and Bhojpur Districts

<div><p>Background</p><p>In the Indian subcontinent, Visceral leishmaniasis is endemic in a geographical area coinciding with the Lower Gangetic Plain, at low altitude. VL occurring in residents of hill districts is therefore often considered the result of <i>Leishmania donovani</i> infection during travel. Early 2014 we conducted an outbreak investigation in Okhaldhunga and Bhojpur districts in the Nepal hills where increasing number of VL cases have been reported.</p><p>Methodology/Principal Findings</p><p>A house-to-house survey in six villages documented retrospectively 35 cases of Visceral Leishmaniasis (VL). Anti-Leishmania antibodies were found in 22/23 past-VL cases, in 40/416 (9.6%) persons without VL and in 12/155 (7.7%) domestic animals. An age- and sex- matched case-control study showed that exposure to known VL-endemic regions was no risk factor for VL, but having a VL case in the neighbourhood was. SSU-rDNA PCR for Leishmania sp. was positive in 24 (5%) of the human, in 18 (12%) of the animal samples and in 16 (14%) bloodfed female <i>Phlebotomus argentipes</i> sand flies. <i>L</i>. <i>donovani</i> was confirmed in two asymptomatic individuals and in one sand fly through hsp70-based sequencing.</p><p>Conclusions/Significance</p><p>This is epidemiological and entomological evidence for ongoing local transmission of <i>L</i>. <i>donovani</i> in villages at an altitude above 600 meters in Nepal, in districts considered hitherto non-endemic for VL. The VL Elimination Initiative in Nepal should therefore consider extending its surveillance and control activities in order to assure VL elimination, and the risk map for VL should be redesigned.</p></div