Search Results (723)

Background/Objectives: The COVID-19 pandemic has significantly impacted global health. However, Africa has reported relatively low numbers of cases and fatalities. Although the pandemic has largely receded, the reasons for its milder course on the African continent have not yet been fully clarified. This study explored the hypothesis that helminth co-infections may have contributed to these observations. Methods: A retrospective cohort study was conducted using 104 plasma samples collected during the third wave of the pandemic in the Ashanti Region of Ghana. Luminex assays were used to measure SARS-CoV-2-specific IgA and IgG, neutralizing antibodies, systemic cytokines and helminth-specific IgG. Results: The results indicated that the highest cumulative seroprevalence of helminths (61.5%) was observed in asymptomatic COVID-19 patients. In comparison, mild and moderate patients had helminth seropositivity rates of 43.8% and 34.5%, respectively, which were 1.4 and 1.8 times lower than those of the asymptomatic group, respectively. Notably, the two severe COVID-19 cases investigated were seronegative for all three of the helminths tested. Strikingly, co-exposure resulted in lower SARS-CoV-2-specific IgA/IgG expression and reduced neutralization potential. However, co-seropositive individuals for helminths and SARS-CoV-2 exhibited a higher expression of Th2 cytokines and IL-10 over Th1 cytokines compared to SARS-CoV-2-positive individuals alone. Conclusion: These data suggest that co-exposure to helminths could mitigate the severity of COVID-19 outcomes by reducing the Th1 and Th17 responses; this highlights the potential protective role of helminthiasis against severe COVID-19. These findings provide valuable insights for the development of public health policies in helminth-endemic regions and underscore the importance of considering helminth co-infections in managing viral infections. It also offers a plausible explanation for the milder disease severity observed in helminth-endemic regions while raising critical considerations regarding vaccine efficacy, as helminth-induced immune modulation may influence the magnitude and quality of vaccine-induced immune responses. Full article

Monitoring the oceans and establishing a global ocean observing system is a task of paramount importance for topics as diverse as the study of climate change, the management of marine environments, and the safety of coastal areas and marine traffic. These systems must be based on long-term observations that allow the correct modeling of the behavior of the seas and the proper environmental management of them. Despite the logical present trend toward automation, in situ measurements from oceanographic vessels are still needed at present, especially when dealing with biogeochemical variables or when seeking information from the subsurface or deep layers of the sea. Long-term measurements by oceanographic vessels can be carried out at one single fixed oceanographic station with a high sampling frequency (typically once a month) or across a grid of stations. In the latter case a larger geographical area is usually covered, but the cost is a reduction of sampling frequency. The question that arises is: what objectives can be achieved, and what questions can be answered according to the sampling frequency and the spatial coverage of the monitoring program? In this work, we analyze the influence of the sampling frequency on the capacity of observing programs to capture the temporal variability of ocean variables at different time scales and to estimate average seasonal cycles and long-term trends. This analysis is conducted through the study of sea surface chlorophyll concentrations in the Western Mediterranean. The trade-off between sampling frequency and spatial coverage is addressed. For this purpose, a monitoring program in the Spanish Mediterranean waters is used as a case study. We show that monthly and fortnightly intervals are the best sampling frequencies for describing the temporal variability of ocean variables as well as their average seasonal cycles. Quarterly sampling could also be appropriate for estimating such seasonal cycles. Surprisingly, the limitations of these low frequency samplings do not arise from the high frequency variability of ocean variables but from the shape of the seasonal cycles. Both high and low frequency sampling designs could be suitable for detecting long-linear trends, depending on the variance of the noise and that of the trend. In the case of quarterly sampling, we show that some statistics improve with the length of the time series, whereas others do not. Although some results may be related to the dynamics of this region, the results are generally applicable to any other marine monitoring system. Full article

This study investigates the mechanical behavior of masonry walls constructed using interlocking compressed earth blocks with dry vertical and horizontal joints. Numerical simulations were conducted to evaluate the performance of this innovative system compared to traditional masonry and to validate experimental findings from previous studies, which identified an orthotropic and non-linear behavior in dry-joint interlocking masonry. The results show that while interlocking masonry exhibits performance comparable to traditional masonry under in-plane loads, it suffers an approximate 20% reduction in resistance under out-of-plane loads, primarily due to the absence of mortar in the horizontal joints. Despite this limitation, the system demonstrates significant economic benefits, achieving cost savings of up to 20% for masonry and 14% for reinforced concrete in conventional construction. These findings highlight the potential of interlocking masonry as a sustainable alternative, although its mechanical behavior under certain load conditions requires further investigation to optimize its structural applications. Full article

Since architectural education has been integrated into academic campuses, the design studio has become its most prominent pedagogical approach. However, in the last three decades, advances in computer-aided design (CAD) and online communication led to the development of virtual design studio (VDS) formats, which gained prominence during the COVID-19 pandemic. VDS and physical design studio (PDS) are characterized by different sociomaterial environments, each offering unique learning opportunities. This study examines how these environments influence learning processes, analyzing two desk critique sessions—one conducted in a VDS and the other in a PDS. Our data, comprising video recordings and on-site observations, were analyzed and interpreted through a sociomaterial lens. The findings indicate that PDS facilitates more spontaneous interactions, allowing for the communication of complex ideas and better addressing misunderstandings compared to VDS, which is constrained by the limitations of digital communication platforms. This research provides both theoretical and pedagogical contributions. Theoretically, it demonstrates how architectural concepts emerge through sociomaterial interactions, framing architectural learning as material practice. In addition, it illustrates the role of sociomaterials in communicating complex ideas and shaping collaborative learning processes. Pedagogically, the findings emphasize the importance of creating rich sociomaterial environments that effectively support intended learning processes. Full article

As global warming continues, extremes in key climate parameters will become more frequent. These extremes are one of the main challenges for the sustainability of cities. The aim of this study is to provide a better understanding of the evolution of extremes in precipitation (pcp) and maximum (Tmax) and minimum (Tmin) temperatures in Grand-Nokoué to improve the resilience of the region. To this end, historical daily precipitation and maximum (Tmax) and minimum (Tmin) temperature data from the Cotonou synoptic station were used from 1991 to 2020. First, the extreme events identified using the 99th percentile threshold were used to analyze their annual and monthly frequency. Secondly, a Generalized Extreme Value (GEV) distribution was fitted to the annual maxima with a 95% confidence interval to determine the magnitude of the specific return periods. The parameters of this distribution were estimated using the method of L moments, considering non-stationarity. The results of the study showed significant upward trends in annual precipitation and minimum temperatures, with p-values of 0.04 and 0.001, respectively. Over the past decade, the number of extreme precipitation and Tmin events has exceeded the expected number. The model provides greater confidence for periods ≤ 50 years. Extreme values of three-day accumulations up to 68.21 mm for pcp, 79.38 °C for Tmin and 97.29 °C for Tmax are expected every two years. The results of this study can be used to monitor hydroclimatic hazards in the region. Full article

Cassava brown streak disease (CBSD) remains the most severe threat to cassava production in the Great Lakes region and Southern Africa. Screening for virus resistance by subjecting cassava to high virus pressure in the epidemic zone (hotspots) is a common but lengthy process because of unpredictable and erratic virus infections requiring multiple seasons for disease evaluation. This study investigated the feasibility of graft-infections to provide a highly controlled infection process that is robust and reproducible to select and eliminate susceptible cassava at the early stages and to predict the resistance of adapted and economically valuable varieties. To achieve this, a collection of cassava germplasm from the Democratic Republic of Congo and a different set of breeding trials comprising two seed nurseries and one preliminary yield trial were established. The cassava varieties OBAMA and NAROCASS 1 infected with CBSD were planted one month after establishment of the main trials in a 50 m² plot to serve as the source of the infection and to provide scions to graft approximately 1 ha. Grafted plants were inspected for virus symptoms and additionally tested by RT-qPCR for sensitive detection of the viruses. The incidence and severity of CBSD and cassava mosaic disease (CMD) symptoms were scored at different stages of plant growth and fresh root yield determined at harvesting. The results from the field experiments proved that graft-infection with infected plants showed rapid symptom development in susceptible cassava plants allowing instant exclusion of those lines from the next breeding cycle. High heritability, with values ranging from 0.63 to 0.97, was further recorded for leaf and root symptoms, respectively. Indeed, only a few cassava progenies were selected while clones DSC260 and two species of M. glaziovii (Glaziovii20210005 and Glaziovii20210006) showed resistance to CBSD. Taken together, grafting scions from infected cassava is a highly efficient and cost-effective method to infect cassava with CBSD even under rugged field conditions. It replaces an erratic infection process with a controlled method to ensure precise screening and selection for virus resistance. The clones identified as resistant could serve as elite donors for introgression, facilitating the transfer of resistance to CBSD. Full article

Ticks are well-known vectors of pathogens, posing considerable risks to livestock health and productivity. In Cameroon, where livestock production is vital, established tick species such as Amblyomma variegatum and Hyalomma truncatum are prevalent in key cattle-rearing areas. The recent introduction of the invasive, acaricide-resistant Rhipicephalus microplus further complicates control efforts. In this study, we deliver baseline data on the composition of tick species and their shifts within agroecological zone I (AEZ I) and agroecological zone III (AEZ III) of Cameroon, providing a foundation for targeted vector control strategies to ultimately reduce the risk of pathogen transmission. From 1100 ticks collected across two Cameroonian agroecological zones, H. truncatum (39.9%), A. variegatum (31%), and R. microplus (10.64%) were the most prevalent species, along with Rhipicephalus lunulatus (4.45%), Hyalomma rufipes (1.45%), Hyalomma marginatum (1.09%), Hyalomma dromedarii (0.45%), and Rhipicephalus sanguineus (0.9%). Molecular identification using cytochrome C oxidase subunit 1 (cox1) and 16s led to the identification of five additional species, Hyalomma nitidum (0.73%), Rhipicephalus simus (3.54%), Rhipicephalus sulcatus (2.64%), Rhipicephalus praetextatus (2.1%), and Rhipicephalus pusillus (1.1%). R. microplus emerged as the most dominant Rhipicephalus spp. in AEZ I, comprising 67.5% of the total Rhipicephalus ticks. In conclusion, we demonstrate the further spread of R. microplus, which represents a major source of vector-borne diseases, affecting both humans and animals. Full article

The fall armyworm (FAW), Spodoptera frugiperda, a major pest in maize production, was assessed for its temporal and spatial distribution in maize fields during both the dry and rainy seasons of 2021 and 2022 in two agroecological regions in Benin (zone 6 and 8). Zone 6 (AEZ 6) “called zone of terre de barre” (Southern and Central Benin) consisted of ferralitic soils, a Sudano-Guinean climate (two rainy seasons alternating with two dry seasons) with a rainfall ranging between 800 and 1400 mm of rainfall per year; while zone 8 (AEZ 8) called “fisheries region” (Southern Benin” is characterized by coastal gleysols and arenosols with a Sudano-Guinean climate and a rainfall of 900–1400 mm of rainfall per year. In this study, 30 and 50 maize plants were randomly sampled using a “W” pattern during the dry and rainy seasons, respectively. Larval density, larval infestation rates, and damage severity were monitored over time. Taylor’s power law and the mean crowding aggregation index were applied to evaluate the dispersion patterns of the larvae. The results indicate a higher larval infestation rate and larval density in AEZ 8 compared to AEZ 6 during the dry season. In the rainy season, while the percentage of damaged plants was higher in AZE 8, no significant differences in larval density between the two zones were observed. The dispersion analysis revealed moderate aggregation (aggregation index = 1.25) with a basic colony of 2.08 larvae, i.e., an average initial cluster of 2.08 larvae observed per plant, reflecting the aggregation oviposition behavior of FAW. This study provides valuable monitoring data on the FAW’s distribution, offering insights for further research on population dynamics and developing predictive models for integrated pest management strategies. Full article

Background: Cardiogenic shock (CS), characterized by inadequate tissue perfusion due to cardiac dysfunction, has a high mortality rate despite advances in treatment. Systemic inflammation and organ failure exacerbate the severity of CS. Extracorporeal hemadsorption techniques such as CytoSorb^® have been introduced to control inflammation. However, evidence of their efficacy, particularly in patients on various mechanical circulatory support (MCS) systems, remains limited. Methods: This retrospective study analyzed data from 129 CS patients treated with CytoSorb^® at the University Hospital of Marburg between August 2019 and December 2023. Those patients receiving MCS were grouped according to MCS type: (1) Impella, (2) VA-ECMO, and (3) ECMELLA. The hemodynamic parameters of circulatory support (e.g., MCS flow rates and vasoactive inotropic score, VIS) and laboratory and ventilation parameters were assessed 24 h before start of CytoSorb^® therapy (T1) and 24 h after completion of CytoSorb^® therapy (T2). Results: Of 129 CS patients (mean age: 64.7 ± 13.1 years), 103 (79.8%) received MCS. Comparing T1 and T2, there was a significant reduction in VIS in the entire cohort (T1: 38.0, T2: 16.3; p = 0.002), with a concomitant significant reduction in the level of MCS support in all subgroups, indicating successful weaning. Analysis of laboratory parameters showed significant reductions in lactate (T1: 2.1, T2: 1.3 mmol/L; p = 0.014), myoglobin (T1: 1549.0, T2: 618.0 µg/L; p < 0.01), lactate dehydrogenase (T1: 872.0, T2: 632.0 U/L; p = 0.048), and procalcitonin (T1: 2.9, T2: 1.6 µg/L; p < 0.001). However, a significant decrease in platelets (T1: 140.0, T2: 54.0 tsd/µL; p < 0.001) and albumin (T1: 25.0, T2: 22.0 g/dL; p < 0.001) was also documented. The median SOFA score of the entire cohort was 15.0 (IQR 12.0–16.0), predicting a mortality rate of >80%, which could be reduced to 60.5% in the present study. Conclusions: During CytoSorb^® therapy in CS, a significant reduction in VIS was demonstrated, resulting in improved organ perfusion. Therefore, the results of this study underline that CytoSorb^® therapy can be considered a useful “component” in the complex management of CS, especially when combined with MCS. To refine and optimize treatment strategies in CS, prospective studies are needed to better define the role of hemadsorption. Full article

In July 2009, African leaders adopted the Declaration on Land Issues in Africa, reaffirming the commitment of African Union member states to effective land management. The declaration emphasizes the protection of land rights for all, with particular attention to women and marginalized groups. Land governance in Africa, which spans various aspects of society, remains a critical issue and is often a source of conflict and instability across the continent. This study examines the legal and institutional reforms of land governance in Francophone Africa (Benin, Burkina Faso, Ivory Coast, Mali, and Senegal), analyzing their objectives, outcomes, and the challenges associated with their implementation. In addition, this study highlights examples of both effective and ineffective reform implementations based on case studies from countries with notable successes (Ethiopia, Rwanda, Mauritius, Ghana, and Madagascar) and failures (South Africa and Zimbabwe). Finally, this study offers recommendations for improving sustainable land management while considering social, economic, political, and environmental dimensions. The methodology employed is based exclusively on a systematic review guided by the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) approach, applied to the ROSES (Reporting Standards for Systematic Evidence Syntheses) protocol. This approach facilitated the selection of 57 relevant documents retrieved from databases such as Scopus, Web of Science, PubMed, and Google Scholar. Land governance in Francophone Africa varies significantly from country to country and cannot be comprehensively addressed in a study of this scope. Nevertheless, this research study identifies common challenges, opportunities, and measures that could inspire reflection in other countries. In several cases, administrative and customary authorities play central roles in land management. However, their overlapping responsibilities, often marked by corruption, extend procedures and exacerbate local conflicts. Full article

Low vegetable consumption in sub-Saharan Africa partly arises from limited availability across cereal-based zones. A field experiment in southern Benin (April to September 2023) evaluated four maize–chili and five maize–mungbean relay intercropping. Growth and yield data and farmers’ perceptions were analyzed using analysis of variance with the least significant difference test, land equivalent ratio (LER) and monetary indexes. Maize grain yield was statistically similar across patterns, whereas chili and mungbean yields differed significantly. All sowing patterns achieved LER > 1. Pattern (1:1) maize–chili had a modest LER (1.15), while treatment (1:3) had a high LER (1.60) for mungbean–maize. Both patterns showed high actual yield gain and intercropping advantage. Pattern (2:2) for maize–chili and pattern (1:3) for maize–mungbean yielded the greatest gross return (7796.6 USD/ha and 1301.2 USD/ha, respectively). Sole mungbean and all intercropping sowing patterns significantly increased mineralizable carbon. Pattern (1:3) maize-mungbean slightly increased total nitrogen and potassium. Farmers ranked the highest pattern (2:2) for maize–chili and (1:3) for maize–mungbean due to sup erior weed, water, and soil management and increased yields. These findings suggest that diversified maize systems incorporating chili pepper and mungbean offer economic benefits and better soil health in southern Benin. Full article

Ticks are important vectors of a wide range of pathogens with significant medical and veterinary importance. Different tick species occupy different habitats with an overall widespread geographical distribution. In addition to their role as reservoirs or vectors, ticks are involved in maintaining pathogens in the environment and among wild and domestic animals. In this study, tick species infesting wild animals, as well as collected from the environment and their pathogens reported in 17 countries in Africa between 2003 and 2023, were collected according to the PRISMA guidelines. Data on ticks resulted in a total of 40 different tick species from 35 different wild animal species. Among the ticks, 34 infectious agents were noted including parasitic (Babesia, Theileria, Hepatozoon, Eimeria), bacterial (Anaplasma, Bartonella, Borrelia, Candidatus Midichloria mitochondrii, Candidatus Allocryptoplasma spp., Coxiella, Ehrlichia, Francisella, and Rickettsia), and a surprisingly high diversity of viral pathogens (Bunyamwera virus, Crimean-Congo Haemorhagic Fever virus, Ndumu virus, Semliki Forest virus, Thogoto virus, West Nile virus). These results highlight the public health and veterinary importance of the information on tick-borne infections. This knowledge is essential to strive to implement programs for sustainable control of ticks and tick-borne diseases. Full article

Globally, agriculture is facing significant challenges due to climate change, which is seriously affecting grain yields. This research aims to analyze the significant effect of climate change (temperature and rainfall) on cereal production in Benin. The choice of Benin is explained by its strong dependence on agriculture and its vulnerability to climatic variations. This study employed climate and agricultural data from FAO and ASECNA (1990–2020) to evaluate the impacts of climate change on cereal production. SARIMA time-series models were used for forecasting, while the PLS-SEM approach assessed the relationships between climate variables and cereal production. The findings reveal a rise in temperatures and a gradual decline in precipitation. Despite these challenges, the time-series analysis suggests that Beninese farmers are expanding cultivated areas, successfully increasing production levels, and improving yields. Projections to 2050 indicate an increase in areas and production for maize and rice, while sorghum shows a constant trend. However, even with these projections, it is recommended to explore, in more depth, the resilience strategies used by cereal producers to better understand their influence and refine the orientations of future agricultural policies. Full article

Background/Objective: Knee osteoarthritis (OA) is a common and debilitating condition affecting older adults, often progressing to advanced stages and requiring total joint replacement. Exercise therapy is widely recognized as the first-line approach for the prevention and initial management of OA. This systematic review assessed the effectiveness of home-based exercises (HBEs) compared to supervised exercises in alleviating pain and reducing disability among patients with knee OA. Methods: A systematic search of PubMed, Cochrane Library, and ScienceDirect identified randomized controlled trials (RCTs) published between January 2001 and October 2024. Methodological quality was evaluated using the Physiotherapy Evidence Database (PEDro) scale, and a meta-analysis was conducted to quantify the efficacy of these interventions. Results: Ten RCTs involving 917 patients were included, ranging in moderate to high methodological quality (PEDro score: 6.3 ± 1.2). Intervention durations ranged from 4 to 12 weeks. Both supervised and HBEs were found to be effective, but supervised exercises demonstrated statistically significant improvements in pain (SMD = −0.45 [95% CI −0.79; −0.11], p = 0.015) and disability (SMD = −0.28 [95% CI −0.42; −0.14], p < 0.001) compared to HBEs. Conclusions: Despite the superiority of supervised exercises over HBEs, considering the cost-effectiveness and ease of implementation of HBEs, we developed recommendations to create a hybrid rehabilitation program that combines both approaches to maximize clinical outcomes. Full article