Spatial Modelling of Common Chimpanzees’ (Pan troglodytes schweinifurthii) Ecological Niche in the Western Part of Rwanda

The Western Part of Rwanda is a mountainous region that hosts two important forest parks namely the Nyungwe National Park (NNP) and Gishwati-Mukura National Park (GMNP). The two parks which are located in the Albertine Rift region are known for their high endemism and harbour several endangered plant and animal species, including particularly the Common Chimpanzees (Pan troglodytes schweinifurthii). However, these forests are facing threats including mainly habitat loss, aggravated by climate change both of which are continuously having direct and indirect effects to the Chimpanzees. While conservation of chimpanzees appears critical, there is a need to deeply understand the dynamics of their habitat. This study aimed at modelling the ecological niche of common chimpanzee by integrating species distribution data and environmental layers. Species location data collected in both NNP and GMNP were integrated with environmental variables (temperature, precipitation, altitude, and land cover) through Maximum Entropy (MaxEnt), and Generic Algorithm for Rule-based Prediction (GARP) Models. The results of both models showed that chimpanzees prefer the Southern and the Northern parts of the study area (0.5 < p < 0.87), which is characterised by high altitude, low temperature, and intensive rainfall. It was also noted that MaxEnt predictions were more accurate compared to the GARP’s. MaxEnt predictions showed that 35% (2058.61 ha) of the Western Province are suitable for chimpanzees, while GARP predicted that only 24% (1411.62 ha) are suitable. Furthermore, the study found that the high precipitation, annual and maximum precipitations, and food availability are the most determinants of chimpanzees' habitat. The land use in the Western Province has made the central part less suitable to chimpanzees and therefore, this study recommends that special efforts for the conservation of Common chimpanzees in Rwanda should be concentrated in the Southern Part (around NNP) Nyungwe National Park (main forest and Cyamudongo fragment) and the northern Part (around GMNP) Keywords: Spatial Modelling, Common Chimpanzee, Ecological Niche, Nyungwe National Park, Gishwati-Mukura National Park, Rwanda

Integrating Remote Sensing and GIS to Model Forest Fire Rik in Virunga Massif, Central - Eastern Africa

This study aimed at developing a forest fire risk model using a combination of GIS and Remote sensing techniques, which helped to identify the level of forest fire vulnerability in Virunga Massif, located at the edge of central and eastern Africa. The Analytic Hierarchical Process (AHP) approach was employed to rank and weigh the key variables and combine them into different fire risk input factors which were later integrated into the main forest fire risk model. The main input datasets, which were linked with a potential source of a forest fire, include the land cover (specifically vegetation type data generated through the Landsat 8 image classification); topographic variables such as slope, elevation and aspect retrieved from the existing Digital Elevation Model (DEM) of Rwanda; the concentration of illegal activities and proximity to beehives sites; as well as visibility from the road and human settlements. Input factor maps were generated, assigned weights and combined in a GIS environment to produce a Virunga massif fire risk model map, which was validated using the existing burnt areas map, and ground truth points recorded using GPS. The study found that the ignition factors are the most forest fire triggering factors in Virunga massif, followed by topographic factors which play a major role in the fire spreading across the ecosystem. The high forest fire risk areas were found in steep slope location around the peaks of the volcanoes, whereas areas with the lowest risk of forest fire were found inside the forest at gentle slopes. The model was validated at 75% accuracy using ground truth data. The study proposes measure to halt the ignition factors through prevention of illegal activities in the Virunga massif for the successful prevention of the forest fire risk in the ecosystem, with much effort invested during the dry season, along with the relocation of beehives to a farther distance from the ecosystem’s edge. Keywords: Forest Fire Risk Modelling, Biodiversity, Illegal Activities, Ignition Factors, Topographic Factors, Analytic Hierarchy Proces

A Novel Epidemic Model for the Interference Spread in the Internet of Things

: Due to the multi-technology advancements, internet of things (IoT) applications are in high demand to create smarter environments. Smart objects communicate by exchanging many messages, and this creates interference on receivers. Collection tree algorithms are applied to only reduce the nodes/paths’ interference but cannot fully handle the interference across the underlying IoT. This paper models and analyzes the interference spread in the IoT setting, where the collection tree routing algorithm is adopted. Node interference is treated as a real-life contamination of a disease, where individuals can migrate across compartments such as susceptible, attacked and replaced. The assumed typical collection tree routing model is the least interference beaconing algorithm (LIBA), and the dynamics of the interference spread is studied. The underlying network’s nodes are partitioned into groups of nodes which can affect each other and based on the partition property, the susceptible–attacked–replaced (SAR) model is proposed. To analyze the model, the system stability is studied, and the compartmental based trends are experimented in static, stochastic and predictive systems. The results shows that the dynamics of the system are dependent groups and all have points of convergence for static, stochastic and predictive systems

A molten salt test loop for component and instrumentation testing

Molten salt is an effective coolant for a wide range of applications, including nuclear reactors, concentrated solar power, and other high temperature industrial heat transfer processes. The technical readiness level of components and instrumentation for high-temperature molten salt applications needs improvement for molten salt to be more widely adopted. A molten salt test loop was designed, built, and commissioned as a test bed to address these issues. The molten salt test loop at Abilene Christian University was built out of 316 stainless steel with a forced flow centrifugal-type pump, and was instrumented for remote operation. A low-temperature molten nitrate salt was used in this system, which was designed to operate at temperatures up to 300 ◦C and flow rates up to 90 liters per minute. This paper describes the loop design, computational fluid dynamics modeling, construction, and commissioning details. An outline of the data acquisition and control systems is presented. Salt samples were taken before and after introduction into the loop, and melting points were measured both before and after salt circulation. Performance of the system is discussed as well as improvements required for higher temperature loops envisioned for the future

Spatial modelling of malaria risk factors in Ruhuha sector in the east of Rwanda

Malaria is a vector borne disease posing a severe health risk to the population of Sub Saharan Africa and particularly in the East African Rift-Valley Region. The fact that malaria is still killing hundreds of thousands of people annually is due to insufficient researchers about its causing factors and the inefficiency of its control measures. With three main objectives: (1) to identify and map potential anopheles mosquito habitat, (2) to determine and map malaria prevalence, and, (3) to assess the relationship between malaria prevalence and malaria risk factors; the aim of this study is to spatially model malaria risk factors in a primarily rural area situated in South Eastern Rwanda. The data used in this research were obtained through a combination of high-resolution ortho-photography obtained from Rwanda Natural Resources Authority (RNRA) and primary data collection. In addition to this, detailed malaria occurrence and socio-economic data were obtained from Rwanda Biomedical Center (RBC). Spatial clusters of malaria occurrence were subsequently determined using Getis and Ord spatial statistics. This cluster analysis showed that malaria distribution is characterized by zones with high malaria risk, so called hot spots, zones with moderate malaria risk known as not significant spots and zones of low malaria risk known as cold spots. The current research demonstrates that malaria prevalence varies from one household to another and from one administrative unit (village) to another. The relationship between malaria prevalence and malaria risk factors was assessed using a logistic regression model. Results clearly indicate that malaria infection increases with the proximity to irrigated farmland. It also increases with household size. It was also proven that lower housing quality (mud houses; unburnt brick walls, earth floor) is associated with higher risk of malaria infection. This research proves that the proximity to irrigated farmland, the household size and housing quality are the main malaria underlying factors in the study area. It therefore suggests that people should not only live far from irrigated farmlands which are considered as the main anopheles mosquito breeding sites but also the housing quality should be improved

Assessment of Grain Legumes Adaptation to Climate Change in Bugesera District, Rwanda

The aim of this study was to assess the adaptability to climate change of selected grain legumes (including beans, peas and soybeans) in Bugesera district in Rwanda. Climate change was analysed by considering significant changes in mean, minimum and maximum temperature and the mean annual rainfall from 1970 until 2014, the year during which data for this study were collected. The sampling strategy followed a cluster area sampling and random sampling approach, which led to the sample size of 99 households surveyed using a structured questionnaire. MAKESENS model and Analysis of Variances (ANOVA) were applied to analyze climate data and information from the household survey. This study revealed significant increase of mean temperature (0.39oC and 0.46oC per decade for rainy seasons A and B respectively) and irregularity of rainfalls during both rainy seasons. The Diurnal Temperature Range (DTR) has been decreasing considerably, impacting the crops development traits such as internode length. The farmers’ responses indicated low adaptation capacity to the climate change, leading to a high sensitivity of the grain legumes. For an improved mitigation of climate change impacts, the following strategies were proposed: land consolidation and creation of grain legumes farmers’ cooperatives, improved economic capacity of the farmers, use of climate-resilient selected seeds, creation of the off-farm activities, improved climate information reliability and dissemination

Short- vs Standard-Course Outpatient Antibiotic Therapy for Community-Acquired Pneumonia in Children: The SCOUT-CAP Randomized Clinical Trial

Importance: Childhood community-acquired pneumonia (CAP) is usually treated with 10 days of antibiotics. Shorter courses may be effective with fewer adverse effects and decreased potential for antibiotic resistance. Objective: To compare a short (5-day) vs standard (10-day) antibiotic treatment strategy for CAP in young children. Design, Setting, and Participants: Randomized double-blind placebo-controlled clinical trial in outpatient clinic, urgent care, or emergency settings in 8 US cities. A total of 380 healthy children aged 6 to 71 months with nonsevere CAP demonstrating early clinical improvement were enrolled from December 2, 2016, to December 16, 2019. Data were analyzed from January to September 2020. Intervention: On day 6 of their originally prescribed therapy, participants were randomized 1:1 to receive 5 days of matching placebo or 5 additional days of the same antibiotic. Main Outcomes and Measures: The primary end point was the end-of-treatment response adjusted for duration of antibiotic risk (RADAR), a composite end point that ranks each child\u27s clinical response, resolution of symptoms, and antibiotic-associated adverse effects in an ordinal desirability of outcome ranking (DOOR). Within each DOOR rank, participants were further ranked by the number of antibiotic days, assuming that shorter antibiotic durations were more desirable. Using RADAR, the probability of a more desirable outcome was estimated for the short- vs standard-course strategy. In a subset of children, throat swabs were collected between study days 19 and 25 to quantify antibiotic resistance genes in oropharyngeal flora. Results: A total of 380 children (189 randomized to short course and 191 randomized to standard course) made up the study population. The mean (SD) age was 35.7 (17.2) months, and 194 participants (51%) were male. Of the included children, 8 were Asian, 99 were Black or African American, 234 were White, 32 were multiracial, and 7 were of unknown or unreported race; 33 were Hispanic or Latino, 344 were not Hispanic or Latino, and 3 were of unknown or unreported ethnicity. There were no differences between strategies in the DOOR or its individual components. Fewer than 10% of children in either strategy had an inadequate clinical response. The short-course strategy had a 69% (95% CI, 63-75) probability of a more desirable RADAR outcome compared with the standard-course strategy. A total of 171 children were included in the resistome analysis. The median (range) number of antibiotic resistance genes per prokaryotic cell (RGPC) was significantly lower in the short-course strategy compared with the standard-course strategy for total RGPC (1.17 [0.35-2.43] vs 1.33 [0.46-11.08]; P =.01) and β-lactamase RGPC (0.55 [0.18-1.24] vs 0.60 [0.21-2.45]; P =.03). Conclusions and Relevance: In this study, among children responding to initial treatment for outpatient CAP, a 5-day antibiotic strategy was superior to a 10-day strategy. The shortened approach resulted in similar clinical response and antibiotic-associated adverse effects, while reducing antibiotic exposure and resistance. Trial Registration: ClinicalTrials.gov Identifier: NCT02891915.

Efficacy and safety of azithromycin versus placebo to treat lower respiratory tract infections associated with low procalcitonin: a randomised, placebo-controlled, double-blind, non-inferiority trial

BACKGROUND: Lower respiratory tract infections are frequently treated with antibiotics, despite a viral cause in many cases. It remains unknown whether low procalcitonin concentrations can identify patients with lower respiratory tract infection who are unlikely to benefit from antibiotics. We aimed to compare the efficacy and safety of azithromycin versus placebo to treat lower respiratory tract infections in patients with low procalcitonin. METHODS: We conducted a randomised, placebo-controlled, double-blind, non-inferiority trial at five health centres in the USA. Adults aged 18 years or older with clinically suspected non-pneumonia lower respiratory tract infection and symptom duration from 24 h to 28 days were eligible for enrolment. Participants with a procalcitonin concentration of 0·25 ng/mL or less were randomly assigned (1:1), in blocks of four with stratification by site, to receive over-encapsulated oral azithromycin 250 mg or matching placebo (two capsules on day 1 followed by one capsule daily for 4 days). Participants, non-study clinical providers, investigators, and study coordinators were masked to treatment allocation. The primary outcome was efficacy of azithromycin versus placebo in terms of clinical improvement at day 5 in the intention-to-treat population. The non-inferiority margin was -12·5%. Solicited adverse events (abdominal pain, vomiting, diarrhoea, allergic reaction, or yeast infections) were recorded as a secondary outcome. This trial is registered with ClinicalTrials.gov, NCT03341273. FINDINGS: Between Dec 8, 2017, and March 9, 2020, 691 patients were assessed for eligibility and 499 were enrolled and randomly assigned to receive azithromycin (n=249) or placebo (n=250). Clinical improvement at day 5 was observed in 148 (63%, 95% CI 54 to 71) of 238 participants with full data in the placebo group and 155 (69%, 61 to 77) of 227 participants with full data in the azithromycin group in the intention-to-treat analysis (between-group difference -6%, 95% CI -15 to 2). The 95% CI for the difference did not meet the non-inferiority margin. Solicited adverse events and the severity of solicited adverse events were not significantly different between groups at day 5, except for increased abdominal pain associated with azithromycin (47 [23%, 95% CI 18 to 29] of 204 participants) compared with placebo (35 [16%, 12 to 21] of 221; between-group difference -7% [95% CI -15 to 0]; p=0·066). INTERPRETATION: Placebo was not non-inferior to azithromycin in terms of clinical improvement at day 5 in adults with lower respiratory tract infection and a low procalcitonin concentration. After accounting for both the rates of clinical improvement and solicited adverse events at day 5, it is unclear whether antibiotics are indicated for patients with lower respiratory tract infection and a low procalcitonin concentration. FUNDING: National Institute of Allergy and Infectious Diseases, bioMérieux