Guinea Region Research Articles

Validating a tailored drought risk assessment methodology: drought risk assessment in local Papua New Guinea regions

Abstract. Climate change is increasing the frequency and intensity of natural hazards, causing disastrous impacts on vulnerable communities. Pacific Small Island Developing States (SIDS) are of particular concern, requiring resilient disaster risk management consisting of two key elements: proactivity and suitability. Drought risk knowledge can inform resilient risk management, but it is currently underexplored in Pacific SIDS, particularly in the highly vulnerable nation of Papua New Guinea (PNG). A tailored, meaning highly specific to the area under investigation, drought risk assessment methodology is key for expanding risk knowledge in vulnerable communities. A semi-dynamic and tailored drought risk assessment methodology to be utilised in PNG was developed in this research. Representative hazard, vulnerability, and exposure indicators were selected, and integrated geographic information system (GIS) processes were used to produce hazard, vulnerability, exposure, and risk indices and maps. The validity of the risk assessment was investigated with a retrospective risk assessment of drought in PNG (from 2014–2020) paired with a literature assessment (as a ground-truth source), and a sensitivity analysis. The preliminary drought risk assessment methodology demonstrated in this study was overall deemed valid and robust, with supplementary improvements proposed for consideration in future investigation. The developed methodology makes strides in addressing methodological knowledge gaps in drought risk assessment, for global assessments and those specific for PNG, and demonstrates the potential for risk assessment to inform resilient drought management practices in at-risk areas. Overall, the results of this study directly contribute to enhancing provincial drought risk knowledge in PNG.

A new large Oreophryne species from the mountains of Papua Province, Indonesian New Guinea (Amphibia, Anura, Microhylidae)

The microhylid genusOreophrynereaches its greatest diversity in the New Guinea region, where more than 60 species have been documented to date. MostOreophryneare small (<30 mm SVL) and only three species,O. anthonyi,O. idenburgensisandO. inornata, exceed 40 mm SVL adult body size. Here we describe a fourth large species ofOreophrynethat was collected in 1998 from the mountains of Papua Province in western New Guinea. In having a cartilaginous connection between the procoracoid and scapula it is most similar toO. idenburgensis, a species known only from the mountains of central-western New Guinea but differs from that species in a suite of morphological characters including a broader head, a hidden (vs. visible) tympanum and a more pointed snout.

Influence of Landscape Patterns on Exposure to Lassa Fever Virus, Guinea.

Lassa fever virus (LASV) is the causative agent of Lassa fever, a disease endemic in West Africa. Exploring the relationships between environmental factors and LASV transmission across ecologically diverse regions can provide crucial information for the design of appropriate interventions and disease monitoring. We investigated LASV exposure in 2 ecologically diverse regions of Guinea. Our results showed that exposure to LASV was heterogenous between and within sites. LASV IgG seropositivity was 11.9% (95% CI 9.7%-14.5%) in a coastal study site in Basse-Guinée, but it was 59.6% (95% CI 55.5%-63.5%) in a forested study site located in Guinée Forestière. Seropositivity increased with age in the coastal site. We also found significant associations between exposure risk for LASV and landscape fragmentation in coastal and forested regions. Our study highlights the potential link between environmental change and LASV emergence and the urgent need for research on land management practices that reduce disease risks.

Factors associated with the ownership and use of insecticide-treated nets in Guinea: an analysis of the 2018 Demographic and Health Survey

BackgroundMalaria is a leading cause of outpatient visits and deaths among children in Guinea. Despite several mass distribution campaigns of insecticide-treated nets (ITNs) in Guinea, ITN ownership and use remain low. Identifying the underlying factors affecting household ITN ownership and ITN usage among those with access will allow the Guinea National Malaria Control Programme to develop targeted initiatives to improve bed net ownership and usage.MethodsTo understand national and regional drivers of ITN ownership and use, multivariable binary logistic regression models were applied to data from the 2018 Demographic and Health Survey to identify risk factors of household ITN ownership and risk factors of ITN use among individuals with access. Akaike Information Criterion (AIC) was used for model parameter selection. Odds ratios were estimated with corresponding 95% confidence intervals.ResultsThe proportion of households in Guinea with at least one ITN was 44%, ranging from a low of 25% in Conakry to a high of 54% in Labé. Use of ITNs among those with access was 66.1% nationally, ranging from 35.2% in Labé to 89.7% in N'zérékoré. Risk factors for household ITN ownership were household size, marital status of the household head, education level of the household head, and region. For ITN use among those with access, risk factors were age, wealth quintile, marital status, and region. In the seven regions of Guinea and capital of Conakry, risk factors for household ITN ownership were household size in Boké, Faranah, and Kankan; education level of the household head in Boké, Faranah, and N’zérékoré; age of the household head in Conakry and Labé; children under five in the household in Kankan; and wealth quintile in Mamou. For ITN use among those with access, risk factors were marital status in Conakry, Faranah, Kindia, Labé, Mamou, and N’zérékoré; place of residence in Labé; children under five in the household in Labé; wealth quintile in Mamou; and age in Faranah and N’zérékoré.ConclusionsThis analysis identified national and region-specific factors that affect ownership and use among those with access in Guinea. Future ITN and social-behavioural change campaigns in Guinea may particularly want to target larger households, households without children, and areas with lower perceived risk of malaria if universal coverage and usage are to be achieved for optimal malaria prevention.

Genome-wide diversity analysis suggests divergence among Upper Guinea and the Dahomey Gap populations of the Sisrè berry (Syn: miracle fruit) plant (Synsepalum dulcificum [Schumach. & Thonn.] Daniell) in West Africa.

Although Synsepalum dulcificum is viewed as one of the most economically promising orphan tree crops worldwide, its genetic improvement and sustainable conservation are hindered by a lack of understanding of its evolutionary history and current population structure. Here, we report for the first time the application of genome-wide single nucleotide polymorphism genotyping to a diverse panel of S. dulcificum accessions to depict the genetic diversity and population structure of the species in the Dahomey Gap (DG) and Upper Guinea (UG) regions to infer its evolutionary history. Our findings suggest low overall genetic diversity but strong population divergence within the species. Neighbor-joining analysis detected two genetic groups in the UG and DG regions, while STRUCTURE distinguished three genetic groups, corresponding to the UG, Western DG, and Central DG regions. Application of Monmonier's algorithm revealed the existence of a barrier disrupting connectivity between the UG and DG groups. The Western DG group consistently exhibited the highest levels of nucleotide and haplotype diversities, while that of the Central DG exhibited the lowest. Analyses of Tajima's D, Fu's Fs, and Achaz Y* statistics suggest that while both UG and Central DG groups likely experienced recent expansions, the Western DG group is at equilibrium. These findings suggest a geographical structuring of genetic variation which supports the conclusion of differential evolutionary histories among West African groups of S. dulcificum. These results provide foundational insights to guide informed breeding population development and design sustainable conservation strategies for this species.

Essential childhood immunization in 43 low- and middle-income countries: Analysis of spatial trends and socioeconomic inequalities in vaccine coverage.

Globally, access to life-saving vaccines has improved considerably in the past 5 decades. However, progress has started to slow down and even reverse in recent years. Understanding subnational heterogeneities in essential child immunization will be critical for closing the global vaccination gap. We use vaccination information for over 220,000 children across 1,366 administrative regions in 43 low- and middle-income countries (LMICs) from the most recent Demographic and Health Surveys. We estimate essential immunization coverage at the national and subnational levels and quantify socioeconomic inequalities in such coverage using adjusted concentration indices. Within- and between-country variations are summarized via the Theil index. We use local indicator of spatial association (LISA) statistics to identify clusters of administrative regions with high or low values. Finally, we estimate the number of missed vaccinations among children aged 15 to 35 months across all 43 countries and the types of vaccines most often missed. We show that national-level vaccination rates can conceal wide subnational heterogeneities. Large gaps in child immunization are found across West and Central Africa and in South Asia, particularly in regions of Angola, Chad, Nigeria, Guinea, and Afghanistan, where less than 10% of children are fully immunized. Furthermore, children living in these countries consistently lack all 4 basic vaccines included in the WHO's recommended schedule for young children. Across most countries, children from poorer households are less likely to be fully immunized. The main limitations include subnational estimates based on large administrative divisions for some countries and different periods of survey data collection. The identified heterogeneities in essential childhood immunization, especially given that some regions consistently are underserved for all basic vaccines, can be used to inform the design and implementation of localized intervention programs aimed at eliminating child suffering and deaths from existing and novel vaccine-preventable diseases.

Population-specific positive selection on low CR1 expression in malaria-endemic regions.

Complement Receptor Type 1 (CR1) is a malaria-associated gene that encodes a transmembrane receptor of erythrocytes and is crucial for malaria parasite invasion. The expression of CR1 contributes to the rosetting of erythrocytes in the brain bloodstream, causing cerebral malaria, the most severe form of the disease. Here, we study the history of adaptation against malaria by analyzing selection signals in the CR1 gene. We used whole-genome sequencing datasets of 907 healthy individuals from malaria-endemic and non-endemic populations. We detected robust positive selection in populations from the hyperendemic regions of East India and Papua New Guinea. Importantly, we identified a new adaptive variant, rs12034598, which is associated with a slower rate of erythrocyte sedimentation and is linked with a variant associated with low levels of CR1 expression. The combination of the variants likely drives natural selection. In addition, we identified a variant rs3886100 under positive selection in West Africans, which is also related to a low level of CR1 expression in the brain. Our study shows the fine-resolution history of positive selection in the CR1 gene and suggests a population-specific history of CR1 adaptation to malaria. Notably, our novel approach using population genomic analyses allows the identification of protective variants that reduce the risk of malaria infection without the need for patient samples or malaria individual medical records. Our findings contribute to understanding of human adaptation against cerebral malaria.

TEMPORARY REMOVAL: Tropical splenomegaly in a migrant-in-transit crossing the Darien gap, Panamá: A probable case of hyper-reactive malarial splenomegaly

Hyper-reactive malarial splenomegaly (HMS), or tropical splenomegaly syndrome, is a severe complication of chronic and recurrent infections caused by Plasmodium spp. This condition typically results in splenomegaly greater than or equal to 10cm and a constellation of laboratory findings, including the absence of identifiable parasites in peripheral blood smears. However, patients with HMS demonstrate serological or molecular evidence of infection. Despite being a familiar entity in malaria holoendemic countries in Africa, and regions of Papua New Guinea, the pathophysiology, natural history, and treatment of the syndrome remains to be fully elucidated. Herein, we describe a highly suggestive case of HMS in a Senegalese patient migrating northbound to reach the U.S.-Mexico border and for whom we provided medical care during his crossing of the Darien Gap in Panama. We also reviewed the literature on diagnosing and treating HMS in-depth.

The Pahoturi River language family, with special reference to its verbal puzzles

Abstract This profile of the Pahoturi River language family of southern Papua New Guinea draws from extensive fieldwork on Idi [ISO 639-3: idi] and Ende [kit] – two of six varieties comprising this family – and brief surveying of the other four, which we illustrate in print for the first time. We present the first typological treatment of Pahoturi River in pursuit of shining more light on this understudied corner of the linguistic landscape. This profile is organized into two parts: first, we present sections on the basic structures and systems of Pahoturi River, illustrated with examples from across the family and supplemented with descriptions of Idi and Ende as relevant. From our preliminary data on the four other varieties, we gather that they are similar to Idi and Ende in many respects, but more investigation is warranted. Second, we provide an in-depth treatment of the verbal complex of Idi and Ende. We highlight two intriguing aspects of these complex systems – analytic constructions and ditransitive indexing – that distinguish the Pahoturi River family and the linguistic region of southern New Guinea.

Knowledge, attitudes, and practices of health providers regarding access to and use of contraceptive methods among adolescents and youth in urban Guinea.

The objective of this study was to analyze providers' knowledge, attitudes, and practices regarding access to and use of contraception by urban adolescents and youth. This is a cross-sectional study of 1,707 health care providers in 173 selected private and public health facilities in the capital city of Conakry and the seven administrative regions of Guinea. Factors associated with health care providers' attitudes and practices were then analyzed using logistic regression. Among the 1,707 health providers, 71% had a good level of Knowledge about modern contraceptive use among adolescents and youth. In addition, 62% had positive attitudes, and 41% had good prescribing practices toward using modern contraceptive methods by adolescents and youth. Being a midwife (aOR: 1.39, 95%CI: 1.02-1.89), Being aged 25-34 years (aOR: 1.7, 95%CI: 1.2-2.3), 35-44 years (aOR: 2.1, 95%CI: 1.4-3.0), and 45 years, and older (aOR: 2.4, 95%CI: 1.3-4.2), an increase of years in professional experience (aOR:1.05; 95%CI: 1.02-1.08) were factors significantly associated with provider positive attitudes. However, being a medical doctor (aOR: 2.37, 95%CI: 1.04-4.42), an increase of years in professional experience (aOR: 1.07; 95%CI: 1.04-1.10) and a positive attitude (aOR: 3.16. 95%CI: 2.48-4.01) were factors associated with good practice in delivering modern contraceptive methods to adolescents and youth. Positive attitudes and good practices toward the use of contraceptive services by adolescents and youth were found among providers. However, many health care providers still have unfavorable attitudes and practices toward delivering FP services to urban adolescents and youth. Therefore, future intervention programs should focus on training health care providers in youth- and adolescent-friendly reproductive health services and promoting contraception among adolescents.

Synopsis of the terrestrial Reptiles of Equatorial Guinea

We present a comprehensive catalogue of the reptiles of Equatorial Guinea, consisting of 118 species belonging to 67 genera and 22 families. There are two species of Crocodylia, ten of Testudines and 106 of Squamata; this last taxon is represented by 62 species of snakes, two amphisbaenians and 42 lizards. Of these 118 species, seven are present only in Annobon, seven only in Bioko, 47 only in Río Muni, 53 occur both in Bioko and Río Muni (or Bioko, Río Muni and other islands), and four are sea turtles. Despite its high diversity, the level of endemism of Bioko is relatively low, with only four endemic species out of the 60 species reported for the island. In contrast, despite its low diversity, Annobon has the highest endemicity level, with five endemic species (and two introduced). No endemic species are known for the rest of the regions of Equatorial Guinea, which contain 100 species. We reveal several new country and species records, and point to some pending taxonomic questions to be addressed. Among the new species records, we highlight the presence of Cyclanorbis elegans, which represents the most meridional known population of the genus. Additional species are expected to be found in Equatorial Guinea as further field and taxonomic work is developed.

Prevalence and factors associated with alcohol consumption in a high school in northern Guinea.

The objective of this study was to determine the prevalence and factors associated with alcohol use in a high school in the Middle Guinea region in West Africa. An analytical cross-sectional study involving 342 high school students was conducted in November 2019 at the Mali centre high school. A questionnaire adapted from the standardised questionnaire validated by the World Health Organization as part of the Global Student Health Surveys was used for data collection. Students were asked about their alcohol use in the 30 days preceding the survey. Using logistic regression, we performed a multivariate analysis that controlled for independent variables to identify factors associated with alcohol use. The age range was 14-27 years. The prevalence of alcohol consumption was 12.28% (95% confidence interval [CI] 8.80, 16.10). Note that 89.80% of the sample studied did not know of any harmful effects of alcohol on health. In a multivariate analysis, we showed that alcohol use was associated with tobacco use (adjusted odds ratio 24.82, 95% CI 20.73, 26.30) and having close friends who also consume alcohol (adjusted odds ratio 4.16, 95% CI 3.63, 6.37). The substantial prevalence of alcohol use, the high proportion of ignorance of the harmful effects of alcohol, and the reasons for the initial motivation for alcohol use found in this study should attract the attention of stakeholders. An action plan based on the two factors associated found could fight alcohol use at Mali centre high school.

Floristic composition and turnover analysis in Dahomey Gap and the surrounding sub-humid Togolese mountain minor forest refuges: Importance for biogeography and biodiversity conservation in sub-Saharan Africa.

The origin of Dahomey Gap (DG) flora is one of the central biogeographical questions in sub‐Saharan, which has been addressed in several studies. However, floristic evidence based on representative samples from the DG seems to be lacking in the scientific debate. The present study was conducted to fill this gap. Specifically, we assessed Togolese mountain riparian forests as minor forest refugia, examined their contribution to larger sub‐Saharan forest refugia, and discussed the significance of these findings for biogeography and biodiversity conservation. Southwest Togo, West Africa, and sub‐Saharan Upper Guinea Region Floristic data were collected in riparian forests through an intensive botanical inventory (n = 198; 50 × 10 m2). A comparative analysis was performed based on the floristic evidence related to forest refuges. The results showed significantly high species richness (868 species) and a high gamma and beta diversity associated with spatial turnover patterns. They also showed a high affinity between the study forests and large sub‐Saharan forest refugia. Riparian forests share about 60% of their current species richness with large sub‐Saharan forest refugia and contained refuge bio‐indicator species. The floristic evidence, consistent with those of other studies, suggests that Togolese mountains would have very ancient origins and have experienced paleoclimatic events. The studied riparian would have served as refuges during recurrent climatic episodes. Our results support the minimal forest fragmentation hypothesis (network of refugia along rivers). However, they seem to be incompatible with the idea that the DG flora may be essentially a relic of the early Holocene. In sub‐Saharan Africa, where maintaining a vast area of natural forest is difficult due to human pressure, efforts to preserve maximum species diversity should include a focus on the conservation of minor forest refuges, particularly in sub‐humid mountain riparian zone.

Resolving the deep phylogeny: Implications for early adaptive radiation, cryptic, and present-day ecological diversity of Papuan microhylid frogs

The microhylid frogs of the New Guinea region are the largest and most ecologically diverse subfamily (Asterophryinae) of one of the largest anuran families in the world and can live in communities of up to 20 species. While there has been recent progress in resolving the phylogenetic relationships of Asterophryinae, significant uncertainties remain, impeding further progress in understanding the evolution of microhabitat use, parental care, and life history variation in this group. In particular, the early divergences at the base of the tree remain unclear; as does the monophyly of some genera; and recent studies have discovered that species with wide geographic distribution are instead cryptic species complexes. In this study, we fortified geographic sampling of the largest previous phylogenetic effort by sequencing an additional 62 taxa and increased data quality and quantity by adding new layers of data vetting and by filling in previously incomplete loci to the five gene dataset (2 mitochondrial, 3 nuclear protein-coding genes) to obtain a dataset that is now 99% complete in over 2400 characters for 233 samples (205 taxa) of Asterophryinae and 3 outgroup taxa, and analyzed microhabitat use data for these taxa from field data and data collected from the literature. Importantly, our sampling includes complete community complements at 19 sites as well as representatives at over 80 sites across New Guinea and its offshore islands. We present a highly resolved molecular phylogeny which, for the first time, has over 95% of nodes supported (84% highly supported) whether using Maximum Likelihood or Bayesian Inference, allowing clarification of all genera (whether monophyletic or clearly not), their sister genera relationships, as well as an age estimate for the Asterophryinae at approximately 20MYA. Early generic diversification occurring between 17 and 12 MYA gave rise to a surprising diversity of about 18 genera as well as the 5 putative microhabitat types. Our tree reveals extensive cryptic diversity calling any widespread taxa into doubt, and clearly demonstrates that complex multispecies communities of Asterophryinae are ecologically diverse, are numerous, and of ancient origin across New Guinea. We discuss the implications of our phylogeny for explaining the explosive diversification of Asterophryinae as the result of adaptive radiation, niche conservatism, and non-adaptive radiation.

A theory-based behavioural change communication intervention to decrease the provision of water to infants under 6 months of age in the Republic of Guinea.

In many countries, the provision of water in the early months of a baby's life jeopardises exclusive breast-feeding (EBF). Using a behavioural theory, this study assessed the impact of a behaviour change intervention on mothers' intention to act and, in turn, on the water provision in addition to breast milk to their infants under 6 months of age (IU6M) in two regions of Guinea. A quasi-experimental design. Data on individual and environmental factors of the theoretical framework, sociodemographic and outcomes were collected using validated questionnaires before and after the intervention. The outcomes examined were the intention to provide water to IU6M, the provision of water and EBF. Path analyses were performed to investigate pathways by which psychosocial and environmental factors influenced the water provision in addition to breast milk. Four health centres were assigned randomly to each study's arm (one control/CG and one intervention group/IG per region). The sample included 300 mothers of IU6M: 150 per group. In IG, the proportion of mothers providing water decreased from 61 % to 29 % before and after the intervention (P < 0·001), while no difference was observed in CG (P = 0·097). The EBF rate increased in IG (from 24·0 % to 53·8 %, P < 0·001) as opposed to CG (36·7 % to 45·9 %, P = 0·107). An association (P < 0·001) between the intention and the behaviour was observed in both groups. An intervention developed using a sound framework reduces the provision of water among IU6M and improves EBF.

Analyzing risks in Naval Operations: The case of visit, board, search and seizure operations in the Côte D’Ivoire Navy

Visit, Board, Search and Seizure (VBSS) operations, which are the preferred modus operandi to deliver law enforcement at sea, have always been, and remain, a risky endeavor. Because this type of operation holds a pivotal role in maritime law enforcement, safe execution is vital to protect involved staff and assets. Hence, this paper analyzes risks associated with VBSS operations; its main aim is to improve the overall level of safety and bring the identified risks under control, by developing associated mitigation measures. First, the risks under discussion were assessed, based on the professional judgment and experience of the naval personnel involved in these operations. Their inputs were introduced in a conceptual framework and the associated results were scored, compared, and benchmarked. It is true that there is an inherent level of risk built in the execution of VBSS operations; although the occurrence of negative incidents/mishaps can be considered marginal for the vast majority of the time, events like these are most often associated with serious consequences. The results of this research effort acknowledged that risk management practices can be useful and have variable performance in bringing risks to as low as reasonably practicable. In this aspect, risk mitigation can be more effective by implementing a systems approach of physical and administrative barriers with four distinct pillars: “Training”, “Equipment”, “Organizational Culture”, and “Procedures”. Highlights Research bridges the gap of knowledge in studies on risks in a key naval operations Novelty of the conceptual research framework designed by authors which has proven to grasp important aspects of naval operations Research addresses performance factors of naval forces securing the Gulf of Guinea region

A participatory epidemiological and One Health approach to explore the community's capacity to detect emerging zoonoses and surveillance network opportunities in the forest region of Guinea.

The Ebola virus disease epidemic that threatened West Africa between 2013 and 2016 was of unprecedented health magnitude. After this health crisis, studies highlighted the need to introduce community-based surveillance systems and to adopt a One Health approach. This study aimed to provide preparatory insights for the definition of a community-based surveillance system for emerging zoonoses such as viral hemorrhagic fevers in Guinea. The objective was to explore the disease detection capacity and the surveillance network opportunities at the community level in two pilot areas in the forest region of Guinea, where the epidemic emerged. Based on a participatory epidemiological and One Health approach, we conducted Focus Group Discussions with human, animal and ecosystem health actors. We used a range of participatory tools, included semi-structured interviews, ranking, scoring and flow diagram, to estimate the local knowledge and perception of diseases and clinical signs and to investigate the existing health information exchange network and its related strengths and weaknesses. The results showed that there is heterogeneity in knowledge of diseases and perception of the clinical signs among actors and that there are preferred and more effective health communication channels opportunities. This preparatory study suggests that it is necessary to adapt the case definitions and the health communication channels to the different actors who can play a role in a future community-based surveillance system and provides recommendations for future surveillance activities to be carried out in West Africa.

Involving the health sector in the prevention and care of female genital mutilation: results from formative research in Guinea

BackgroundDespite efforts to reduce the burden of female genital mutilation (FGM) in Guinea, the practice remains prevalent, and health care providers are increasingly being implicated in its medicalization. This formative study was conducted to understand the factors that facilitate or impede the health sector in providing FGM prevention and care services to inform the development of health sector-based interventions.MethodsBetween April and May 2018, a mixed methods formative study was carried out using a rapid assessment methodology in three regions of Guinea—Faranah, Labe and Conakry. A structured questionnaire was completed by one hundred and fifty health care providers of different cadres and 37 semi-structured interviews were conducted with health care providers, women seeking services at public health clinics and key stakeholders, including health systems managers, heads of professional associations and schools of nursing, midwifery, and medicine as well as representatives of the Ministry of Health. Eleven focus group discussions were conducted with female and male community members.ResultsThis study revealed health systems factors, attitudinal factors held by health care providers, and other factors, that may not only promote FGM medicalization but also impede a comprehensive health sector response. Our findings confirm that there is currently no standardized pre-service training on how to assess, document and manage complications of FGM nor are there interventions to promote the prevention of the practice within the health sector. This research also demonstrates the deeply held beliefs of health care providers and community members that perpetuate this practice, and which need to be addressed as part of a health sector approach to FGM prevention.ConclusionAs integral members of FGM practicing communities, health care providers understand community beliefs and norms, making them potential change agents. The health sector can support them by incorporating FGM content into their clinical training, ensuring accountability to legal and policy standards, and promoting FGM abandonment as part of a multi-sectoral approach. The findings from this formative research have informed the development of a health sector intervention that is being field tested as part of a multi-country implementation research study in Guinea, Kenya, and Somalia.

English

Rice is the staple food in the Republic of Guinea. However, its production is seriously hampered by iron toxicity. The fight against this stress necessarily involves the search for tolerant or resistant varieties. The study aims to determine quantitative trait locus (QTL) associated with tolerance to iron toxicity and to identify genotypes tolerant or resistant to iron toxicity. Thus, 90 local rice accessions collected in two regions of Guinea with high iron toxicity were evaluated using 33,537 single nucleotide polymorphism (SNP) markers. Seventy of the SNP markers expressed a polymorphism rate of 100%. Diversity analysis of the entire collection with these markers revealed a total of 140 alleles, a moderate Nei genetic diversity of 0.426, a fairly high Shannon diversity index of 0.610 and an organization of the accessions into four genetic groups. The study also identified 12 potentially iron-tolerant accessions and five QTLs associated with iron-toxicity tolerance located on chromosomes 1, 2, 3, 11, and 12. The 12 genotypes identified could be exploited in the lowland rice breeding program. &nbsp; Key words: Oryza, abiotic stress, molecular characterization, variability, molecular markers.

Co-Evolution of Parallel Triple Subduction Systems in the New Guinea Region: A Systematic Numerical Study

A specific configuration of the global subduction system is the parallel triple subduction. The widely accepted example of parallel triple subduction is the New Guinea region, including a northward dip at the New Britain Trench (NBT), a southward dip at the Trobriand Trough (TT), and North Solomon Trench (NST). Questions regarding the parallel triple subduction system remain largely unexplored in terms of factors controlling its initiation, duration, and dynamics. Here, we used two-dimensional numerical models to study the dynamics mechanism of the parallel triple subduction system in the New Guinea region. Four possible regimes were achieved: 1) the double subduction model, which includes the forward subduction jumping model (FSJ) and the subduction polarity reversal model (SPR) and 2) the parallel triple subduction model, which includes the tendency to the forward jumping model (TFSJ) and the tendency to polarity reversal (TSPR). By evaluating the four regimes with actual seismic data, we suggest that the pre-existing rupture and length of ocean–continent transition (OCT) determine the formation of the TT, while the formation of the NBT may be the result of the rheological strength differences between the Solomon Island Arc (SIA) and Solomon Sea Basin (SSB); the initial length of the SSB can regulate the competitive relationship between the TT and NBT, which also determines the present-day inactive state of the TT. A longer SSB makes the TT and NBT initiated independently, while a narrower SSB will allow interaction during subduction initiation of the TT and NBT.