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Explainable label guided lightweight network with axial transformer encoder for early detection of oral cancer

A systematic review of automated hyperpartisan news detection

Hyperpartisan news consists of articles with strong biases that support specific political parties. The spread of such news increases polarization among readers, which threatens social unity and democratic stability. Automated tools can help identify hyperpartisan news in the daily flood of articles, offering a way to tackle these problems. With recent advances in machine learning and deep learning, there are now more methods available to address this issue. This literature review collects and organizes the different methods used in previous studies on hyperpartisan news detection. Using the PRISMA methodology, we reviewed and systematized approaches and datasets from 81 articles published from January 2015 to 2024. Our analysis includes several steps: differentiating hyperpartisan news detection from similar tasks, identifying text sources, labeling methods, and evaluating models. We found some key gaps: there is no clear definition of hyperpartisanship in Computer Science, and most datasets are in English, highlighting the need for more datasets in minority languages. Moreover, the tendency is that deep learning models perform better than traditional machine learning, but Large Language Models’ (LLMs) capacities in this domain have been limitedly studied. This paper is the first to systematically review hyperpartisan news detection, laying a solid groundwork for future research.

ZnO-MnO2 co-modified hierarchical porous carbon nanofiber film electrodes for high-energy density supercapacitors

Influence of egg card color preference, inoculation time, generational succession, and learning experience on the parasitism of Trichogramma ostriniae

This study investigated the parasitic selection preferences of female Trichogramma ostriniae on egg cards of different colors, considering the effects of inoculation time, generations, and learning experiences on wasp parasitism. The preferences of female T. ostriniae for oviposition were assessed across egg cards of different colors. Subsequent experiments identified the egg card background color most preferred by T. ostriniae and examined the influence of inoculation time, generations, and learning experiences on parasitism rates. The findings revealed a significant preference for T. ostriniae for yellow egg cards compared to other colors, with the highest parasitism rate observed on yellow and the lowest on red. Inoculation time had a significant effect on the parasitism of T. ostriniae on yellow egg cards, with the highest parasitism observed at 16h post-inoculation and a noticeable negative linear correlation with increasing inoculation time up to 48h (F = 8.73, P<0.05). The number of generations did not significantly affect the parasitism rate of T. ostriniae on yellow egg cards, nor did the learning experiences show a significant difference in the relative parasitism of T. ostriniae on yellow egg cards among the learning experiences. However, T. ostriniae had a significantly higher parasitization rate on yellow egg cards compared to white egg cards, regardless of generation or learning experience. Those results showed that female T. ostriniae strongly prefers yellow. The highest parasitism of female T. ostriniae on yellow egg cards was observed at 16h post-inoculation.

Calcium titanate nanoparticles-induced cytotoxicity, genotoxicity and oxidative stress in human non-small lung cancer cells

Abstract Calcium titanate nanoparticles (CaTiO3NPs) have garnered significant attention due to their unique properties and excellent biocompatibility, which have led to their increased use in various fields and consumer products. This rise in application necessitates a better understanding of their biological and toxicological effects. However, there is limited data on the cytotoxicity and genotoxicity of CaTiO3NPs in human normal skin fibroblasts (HSF) and non-small lung cancer (A-549) cells. Consequently, this study aimed to explore the effect of 48-hour exposure to CaTiO3NPs on cell viability, genomic DNA integrity, and oxidative stress induction in human cancer A-549 cells, compared to normal HSF cells. The cytotoxicity and genotoxicity of CaTiO3NPs were assessed using the Sulforhodamine B (SRB) cytotoxicity and Alkaline Comet assays, respectively. To estimate possible oxidative stress induction and variation in apoptotic gene expression, reactive oxygen species (ROS) analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were also performed. Our findings demonstrated that exposure to CaTiO3NPs for 48 h resulted in low toxicity toward both normal HSF and cancer A-549 cells, with cell death observed only at high concentrations (100 and 1000 µg/ml). The IC50 value of CaTiO3NPs in both HSF and A-549 cells was greater than 1000 µg/ml; specifically, the IC50 value in A-549 cells at 48 h was 1670.65 µg /ml. However, treatment with CaTiO3NPs for 48 h at the IC50 concentration of 1670.65 µg /ml resulted in significant genomic DNA damage and excessive ROS generation, along with a notable disturbance in the expression level of apoptotic (p53 and Bax) and anti-apoptotic Bcl2 genes in A-549 cells. In contrast, no significant changes were observed in HSF cells treated for 48 h with the same concentration (1670.65 µg /ml) of CaTiO3NPs. Collectively, these findings indicated that despite short-term exposure to CaTiO3NPs causing low cytotoxicity in both normal HSF and A-549 cells. CaTiO3NPs were selectively genotoxic toward A-549 cells. This genotoxicity was mediated through excessive ROS generation, which disrupted genomic DNA integrity and altered the expression of apoptotic genes, triggering apoptosis in A-549 cells. Further in vitro and in vivo studies are needed to fully understand the toxicological and biological properties of CaTiO3NPs.

Ghana’s National Health Insurance enrollment: Does the intersection of educational and residential status matter?

Background Since its inception in 2003, Ghana’s Health Insurance Scheme (NHIS) has received considerable scholarly attention on the determinants of enrollment. While most of these studies highlight the role of some socioeconomic and geographical factors, no study has explored the intersection of educational attainment and residence on NHIS enrollment. We aim to contribute to the literature and health policy in Ghana by examining the intersection of educational attainment and rural-urban residence on NHIS enrollment among women and men. Methods We used nationally representative data from the 2022 Ghana Demographic and Health Survey (GDHS). Using STATA 17, we applied multivariable logistic regression to our analytical sample comprising women (n = 14997) and men (n = 7040). Results Overall, we found that more women (90%) than men (73%) enrolled on the NHIS. Adjusting for a range of control variables, we found that women and men with secondary (OR: 1.61, 95% CI: 1.28–2.02; OR: 1.45, 95% CI: 1.16–1.82) and higher education (OR: 1.81, 95% CI: 1.24–2.64; OR: 2.85, 95% CI: 2.03–3.99) were more likely to have enrolled into the NHIS compared to those with no formal education. This difference was particularly heightened among women and men with no education. Rural women (96%) and men (90%) with higher education had higher enrollment rates compared to their urban counterparts. Conclusion We recommend revising the NHIS equity and pro-poor policy to include vulnerability at the intersection of low educational attainment and rural residence.

Theoretical investigation of the mechanism, kinetics and subsequent degradation products of the NO3 radical initiated oxidation of acrolein

Topic: Distribution of Anopheles stephensi bioforms in selected districts of Rajasthan, India

Introduction Anopheles stephensi is a major urban malaria vector in Rajasthan, India, and is responsible for spreading persistent malaria throughout the year. In Rajasthan, An. stephensi is invariably distributed and has three bioforms discriminated based on the number of the ridge on the eggs viz; Type, Mysorensis, and Intermediate. The present study aimed to understand the distribution pattern of these bioforms in rural and urban setups as they also have differences in their malaria transmission capacity. Methods Gravid mosquitoes and the larvae were collected from different habitats of districts of Rajasthan. The gravid females An. stephensi were allowed to lay eggs. These eggs then were subjected to morphometric analysis and counted for the number of ridges for bioform identification. Results About 15000 ± 200 eggs were obtained from ~190 gravid An. stephensi collected from 45 localities (11 Urban & 34 Rural) of eight districts of Rajasthan. Out of which 3569 eggs were subjected to morphometric analysis. Mysorensis bioform (49.7%) was observed to have higher percent over Intermediate (25.5%) and Type (24.6%) bioforms. Mysorensis and Intermediate were found more in rural areas whereas the Type bioform dominated higher in urban areas. Discussion The Mysorensis bioform was found to be dominant throughout the year in all seasons in rural areas. Type bioform preferred indoor breeding places like underground tanks, cement tanks whereas other bioforms preferred outdoor breeding places. Egg size was found to be directly proportional to the number of ridges on the eggs (r = 0.55). No reproductive isolation was observed among these bioforms. Conclusions The Mysorensis bioform is more prominent than other bioforms. Subspecies level understanding helps to plan effective control measures according to the breeding site selection majorly by Type bioform, an efficient vector in this region.

New machine-learning models outperform conventional risk assessment tools in Gastrointestinal bleeding

Abstract Rapid and accurate identification of high-risk acute gastrointestinal bleeding (GIB) patients is essential. We developed two machine-learning (ML) models to calculate the risk of in-hospital mortality in patients admitted due to overt GIB. We analyzed the prospective, multicenter Hungarian GIB Registry’s data. The predictive performance of XGBoost and CatBoost machine-learning algorithms with the Glasgow-Blatchford (GBS), pre-endoscopic Rockall and ABC scores were compared. We evaluated our models using five-fold cross-validation, and performance was measured by area under receiver operating characteristic curve (AUC) analysis with 95% confidence intervals (CI). Overall, we included 1,021 patients in the analysis. In-hospital death occurred in 108 cases. The XGBoost and the CatBoost model identified patients who died with an AUC of 0.84 (CI:0.76–0.90; 0.77–0.90; respectively) in the internal validation set, whereas the GBS and pre-endoscopic Rockall clinical scoring system’s performance was significantly lower, AUC values of 0.68 (CI:0.62–0.74) and 0.62 (CI:0.56–0.67), respectively. ABC score had an AUC of 0.77 (CI:0.71–0.83). The XGBoost model had a specificity of 0.96 (CI:0.92–0.98) at a sensitivity of 0.25 (CI:0.10–0.43) compared with the CatBoost model, which had a specificity of 0.74 (CI:0.66–0.83) at a sensitivity of 0.78 (CI:0.57–0.95). XGBoost and the CatBoost models evaluate the mortality risk of acute GI bleeding better, than the conventional risk assessment tools.

Syphilis seroprevalence and risk factors among first-time blood donors in Brazil: A comprehensive repeated cross-sectional analysis spanning a decade

Background Syphilis remains a global health challenge, with rising incidence rates worldwide Prevalence surveys conducted in Brazil over extended periods of time are scarce. This study examines the secular trends and risk factors for syphilis seroprevalence among first-time blood donors in Brazil. Methods A retrospective analysis was conducted as part of a multicenter, repeated cross-sectional survey of blood donors from four major Brazilian blood centers, covering the period from 2007 to 2020. First-time donors who had undergone valid treponemal screening tests were included in the final dataset. Demographic characteristics and serological results were analyzed to identify risk factors for syphilis seroprevalence using multivariate Poisson models. An interaction term between age group and donation year was added to the final model. Model comparisons were performed using Likelihood Ratio Tests (LRT) and Akaike Information Criterion (AIC). Results 1,424,850 donations from first-time donors were included during the study period. The overall syphilis seroprevalence was 2.19%, with significant heterogeneity across centers. Risk factors for increased seroprevalence included male gender, older age, lower education level, and self-reported black or mixed skin color. Notably, an increasing trend in syphilis seroprevalence was observed among younger donors and those born after 1990. Interaction analyses revealed significant effects between visit period and key demographic variables (age group, gender, education, and ethnicity), with the interaction between age group and donation year indicating higher seroprevalence among younger age groups in recent years. Conclusion The study highlights a high syphilis seroprevalence among first-time blood donors in Brazil, which has significant implications for blood safety and public health. The increasing trend among younger donors suggests a shift towards newer infections, warranting continued surveillance in this demographic.

Prediction and validation of mechanical properties of self-compacting geopolymer concrete using combined machine learning methods a comparative and suitability assessment of the best analysis

Changes in pregnancy-related hormones, neuromechanical adaptations and clinical pain status throughout pregnancy: A prospective cohort study

During pregnancy, increased hormonal levels contribute to ligament laxity of the pelvis and could predispose to lumbopelvic pain. The main objective of this study was to assess changes in pregnancy-related hormones, neuromechanical adaptations and clinical pain status throughout pregnancy. An exploratory objective was to examine the possible association between those variables. Twenty-eight pregnant women participated in the study. At each trimester, they provided a blood sample (to measure relaxin, estrogen and progesterone), completed questionnaires assessing clinical status (functional disability, risk of poor prognosis of prolonged lumbar disability, avoidance behaviors, anxiety and pain catastrophizing), and were asked to perform a flexion-relaxation task (erector spinae electromyography and trunk kinematics). Results showed that throughout pregnancy, nocturnal and diurnal lumbopelvic pain intensity and related-disability, risk of poor lumbopelvic pain prognosis as well as avoidance behaviors increased, while pain catastrophizing decreased. Neuromechanical characteristics of flexion-relaxation task, including low back muscle activity and trunk kinematics, were similar across the three trimesters. Positive correlations were found between disability and estrogen levels (changes between first and second trimester, p = 0.05), and estrogen and diurnal lumbopelvic pain intensity (change between second and third trimester, p = 0.02). A positive correlation was also found between weight and the Pelvic Girdle Questionnaire score (changes between second and third trimester, p = 0.05). Negative correlations were found between weight (change between first and second trimester) and lumbopelvic maximal angle (p = 0.003), FRP onset for pelvic (p = 0.04) and lumbopelvic (p = 0.003) angles as well as FRP cessation for lumbopelvic angle (p = 0.001). These results show that, in pregnant women, pain and disability are associated with hormonal changes rather than trunk neuromechanical characteristics during a flexion-relaxation task. These results suggest that the flexion-relaxation task may not be an appropriate proxy to study vertebral and pelvic muscle control in pregnant women.

Insecticidal activity of Delonix regia (Fabaceae) against the cotton leafworm, Spodoptera littoralis (Bois) with reference to its phytochemical composition

Differences in bacterial community structure and metabolites between the root zone soil of the new high – Fragrance tea variety Jinlong No. 4 and its grandparent Huangdan

With the development of the tea industry, understanding the differences in root zone microecology among different tea varieties is of great significance for improving tea quality and yield. To investigate the microbial and metabolite foundation underlying the disparities in root zone physicochemical properties between the high-aroma new tea variety JL4 (Jinlong No.4) and its grandparent HD (Huangdan), the bacterial diversity, community structure and metabolite distinctions of HD and JL4 root zone soils were analyzed using NovaSeq 6000 high-throughput sequencing and GC-MS-derived metabolomics technologies. The analysis of soil physical and chemical properties showed that, compared with HD, the available phosphorus (AP) in JL4 was significantly decreased (28.91 ±  9.78 mg · kg−1, P < 0.05), and so was the available potassium (AK) at 57.67 ±  4.04 mg · kg−1. The results from 16S rDNA sequencing indicated that, compared with HD, JL4 had a lower Shannon index and a higher abundance of Gram-negative and aerobic-related bacteria. These results indicated that there was a decrease in bacterial diversity in the root zone soil of JL4. The dominant bacterial phyla included Proteobacteria, Acidobacteriota, and Chloroflexi among others. Biomarkers in HD included Firmicutes, Rhizobiales, and Caulobacterales, and biomarkers for JL4 comprised Sphingomonadaceae bacterium URHD0088 and Halomonadaceae. GC-MS derivatization metabolomics highlighted sugars as having the most differential metabolites (8). In JL4, D-manitol 2 and scylo-inositol decreased while (-)-epicatechin, catechin, and D-pinitol increased. KEGG pathway enrichment analysis revealed substantial enrichment in metabolic pathways related to flavonoid biosynthesis. The changes in these metabolites may have a significant impact on the growth and quality of tea plants. Redundancy Analysis (RDA) along with correlation analyses indicated significant impacts on root zone bacterial community structure by factors such as AK, Soil Organic Matter (SOM), NO3−-N (nitrate nitrogen), and pH levels. A significant positive correlation was observed between AK and both Firmicutes and Kapabacteria individually; furthermore, AP exhibited a highly significant positive correlation with Kapabacteria but a significant negative correlation with unidentified Archaea. Catechin and (-)-Epicatechin were significantly negatively correlated with Actinobacteria phylum while showing a significant positive correlation with Verrucomicrobia and Kryptonia phyla. This study systematically compared the microbial and metabolite characteristics of the root zone soil of JL4 and HD for the first time, providing new ideas and methods for tea variety improvement and precision cultivation management, which is expected to promote the high-quality development of the tea industry in the future.

Retrospective detection and whole genome sequencing identify the first local case of Pigeon Rotavirus A infection in Taiwan from 2018

Abstract In 2018, pigeon Rotavirus A G18P[17] was identified in Australia as the causative agent of a disease outbreak presenting as vomiting and diarrhea, reminiscent of the young pigeon disease syndrome. This virus has subsequently been detected in several other countries, including Belgium, Denmark, Germany, Great Britain, Poland, and the United States. This study was conducted to determine the presence of pigeon Rotavirus A among archived samples collected in Taiwan, and to subsequently characterize the whole genome of a local isolate. Two hundred twenty-five pigeon liver samples collected from 2018 to 2023 were tested for the presence of pigeon rotavirus A RNA using PCR. A sample from 2018 tested positive, and the successful rescue of infective virions was achieved. The first coding-complete genome of this virus from Taiwan was successfully sequenced, revealing that isolate NPUST-001 belongs to genotype G18P[17]-I4-R4-C4-M4-A4-T4-N4-E19-H4. To date, this is the earliest known rotavirus A isolate with this exact genotype constellation recovered from a domestic pigeon sample in the Asian region. Phylogenetic analysis of the VP6 segment showed that isolate NPUST-001 belongs to a distinct lineage of pigeon Rotavirus A which comprises of several other strains reported from mainland China and the USA. Although no recent cases were detected, active surveillance for rotaviral infection among suspected cases is recommended to gather more information on the epidemiology of this virus locally.

Enhancing programmatic scale-up: Applying the consolidated framework for implementation research to evaluate decentralized drug-resistant tuberculosis services in Southern Nigeria

Background Decentralization of Drug-Resistant Tuberculosis (DR-TB) services using multilevel interventions was piloted in Akwa-Ibom and Oyo States of Nigeria, which had high rates of pre-treatment loss-to-follow-up in 2021. The varying outcomes of the intervention strategies necessitated understanding what worked well and why. This study aimed to identify enablers and barriers shaping the implementation of decentralized DR-TB services in these states and provide actionable strategies for programmatic scale-up. Methods Semi-structured key informant interviews were conducted with 40 stakeholders involved in the pilot implementation of decentralized DR-TB services in southern Nigeria. Interviews were audio-recorded, transcribed verbatim, and template analysis done using NVivo statistical software, adapting the Consolidated Framework for Implementation Research (CFIR) constructs and sub-constructs as priori codes for data synthesis and analysis. Results The study identified enablers and barriers across the five CFIR domains. Intervention characteristics facilitators stemmed from its relative advantage and design enabling faster notification of diagnosed DR-TB patients, enhanced patient tracking, ease of conducting baseline investigations, bringing treatment closer by reducing transportation challenges, unique role of the Volunteer Liaison Officer, utility of WhatsApp platform, private sector engagement, and DR-TB survivors as peer counsellors. Critical incidents such as the removal of fuel subsidies and economic difficulties; and inner setting factors like existing infrastructure and health workforce, culture, available resources and tension for change from high pre-treatment loss to follow-up, and intervention’s alignment with workflow; all facilitated implementation. Barriers identified included: challenges with verbal autopsy, low adoption of Unstructured Supplementary Service Data (USSD) innovation, pricing of baseline tests, poor power supply, inadequate laboratory facilities and insufficient DR-TB expertise in rural areas, and fear of TB infection among health workers. Conclusion The findings demonstrate the ease of implementing decentralized DR-TB services and their advantages over a centralized approach. Key enablers centered on innovation and individual characteristics, and inner setting dynamics within the TB program. There were more facilitators than barriers, with most barriers being modifiable despite some outer setting factors like fiscal policy and geographic access. These insights can guide nationwide adoption and scale-up of decentralized DR-TB services in Nigeria and similar settings in low-and middle-income countries. Trial Registration Pan African Clinical Trial Registry PACTR202309676675265

Cascaded Fabry-Perot interferometer with thin film based on Vernier effect

Abstract The Vernier effect is often utilized to boost the sensing ability of optical fiber sensors. In this paper, theoretical model of cascaded Fabry-Perot interferometer (FPI) with thin film based on Vernier effect is established. The sensitivities of the envelope spectra, thin film cavity and mixed cavity of air-thin film are analyzed qualitatively. According to the theoretical analysis, although sensitivity from mixed cavity of air-thin film is amplified, the value is equal to the sensitivity of sing thin film cavity. Experimental verification is carried out by an example of thin film named polydimethylsiloxane (PDMS) polymer. Herein, a new FPI constructed by air cavity from a hollow-core fiber, PDMS cavity, and air-PDMS mixed cavity is proposed and demonstrated. In order to facilitate the generation of the Vernier effect, the length of the PDMS cavity is intentionally designed shorter than the air cavity, making the free spectral range of the air-PDMS cavity and air cavity is approximately equal. The temperature change makes the refractive index and thermal expansion of PDMS change, while gas pressure change results in elastic deformation of PDMS. The Vernier envelope wavelength shifts with the temperature and gas pressure change. The proposed FPI features high temperature and gas pressure sensitivities of 3.07 nm/℃, and 23.07 nm/MPa, and a high magnification factor of 17 when the lengths of HCF and PDMS are 82.5 and 3.7 μm, respectively. The experimental results show that the temperature and pressure sensitivities of the cascaded FPI’s envelope spectra are equal to the sensitivity of a single thin film microcavity, and the theoretical calculation is in good agreement with the experimental verification. The theoretical model is also applicable to thin film prepared by other polymer materials. Additionally, the proposed FPI has good stability, reversibility, and repeatability, which is a good choice in the field of optical fiber sensing.

Thermodynamics, economy and environment analyses and optimization of series, parallel, dual-loop Kalina cycles for double-source heat recovery in cement industry

This research aims to investigate the heat recovery of both suspension preheater flue gas and clinker cooler hot air in cement industry. Three thermodynamic cycles including series Kalina Cycle (S-KC)、parallel Kalina Cycle (P-KC) and dual-loop Kalina Cycle (DL-KC) are introduced for converting dual-source heat resources into power to enhance the system efficiency for cement production process. Firstly, the multi-layer comprehensive evaluation models are established for the three thermodynamic cycles. Then, the parametric studies are implemented to estimate the influences of six key parameters on the system’s thermodynamic-economic-environmental performances. Meanwhile, optimization investigations consisting of thermodynamic optimal design (TOD), thermodynamic and economic optimal design (TEOD), and thermodynamic, economic and environmental optimal design (TEEOD) are considered, and the performances of systems and components are compared under three optimal design scenarios. The results prove that, for S-KC, P-KC and DL-KC, the higher net power output (Wnet) can be gained with decreasing condenser outlet temperature and regenerator temperature difference, and increasing evaporator temperature difference and superheat degree, the lower electricity production cost (EPC) can be acquired with decreasing condenser outlet temperature, evaporator temperature difference and regenerator temperature difference, while the less environment impact load (EIL) can be attained with decreasing condenser outlet temperature, regenerator temperature difference and basic ammonia concentration, and increasing superheat degree. In addition, under TOD, TEOD and TEEOD scenarios, DL-KC is the best selection from the thermodynamic, economic and environmental perspectives, with the corresponding Wnet of 7166 kW, 6904 kW and 6838 kW, the EPC of 0.00476 $/kWh, 0.00369 $/kWh and 0.00362$/kWh, the EIL of 0.0597 mPEChina,90/kWh, 0.0599 mPEChina,90/kW and 0.0593 mPEChina,90/kW. It also identifies that the evaporator unit is the key component contributing to exergy destruction and investment cost for three systems, while the pump has the maximum influence on environmental performance.

Author Correction: Identification of CT based radiomic biomarkers for progression free survival in head and neck squamous cell carcinoma

A DNA barcode library for Culex mosquitoes (Diptera: Culicidae) of South America with the description of two cryptic species of subgenus Melanoconion

Among mosquitoes (Diptera: Culicidae), the genus Culex Linnaeus is one of the most diverse in the world and includes numerous known vector species of parasites and viruses to humans. Morphological identification of Culex species is notoriously difficult and relies mostly on the examination of properly dissected male genitalia which largely prevents female and immature identification during entomological, ecological or arboviral surveys. The aims of this study were (i) to establish a DNA barcode library for Culex mosquitoes of French Guiana based on the mitochondrial gene cytochrome c oxidase I (COI) marker, (ii) to compare three approaches of molecular delimitation of species to morphological identification, (iii) to test the effectiveness of the COI marker at a broader geographical scale across South America, and (iv) to discuss the internal classification of the genus Culex as regard to our phylogenetic analysis. Mosquitoes used in this study were sampled in French Guiana between 2013 and 2023. We provide 246 COI sequences for 90 morphologically identified species of Culex, including five new country records and two newly described species. Overall, congruence between morphological identification and molecular delimitations using the COI barcode was high. The Barcode of Life Data clustering approach into Barcode Index Numbers gives the best result in terms of species delimitation. Inconsistencies between morphological identification and molecular delimitation can be explained by introgression, incomplete lineage sorting, imperfect taxonomy or the effect of geographical gap in sampling. This increases by almost two-fold the number of mosquito species for which a DNA barcode is available in French Guiana, including 75% of the Culex species currently known in the territory. Finally, this study confirms the usefulness of the COI barcode in identifying Culex of South America, but also points the limits of this marker for some groups of species within the subgenera Culex and Melanoconion.