This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root dis...This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SMPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors.展开更多
In current report,the structural,magnetic,and thermoelectric properties of RE doped MgPm_(2)X_(4)(X=S,Se) spinels were investigated.The energy difference in ferromagnetic and antiferromagnetic states reveals the stabi...In current report,the structural,magnetic,and thermoelectric properties of RE doped MgPm_(2)X_(4)(X=S,Se) spinels were investigated.The energy difference in ferromagnetic and antiferromagnetic states reveals the stability of MgPm_(2)(S/Se)_(4) in the ferromagnetic states.The co mputation of enthalpy of formation also ascertains thermodynamic stability of crystal structure.Spin-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin channels.The room temperature ferromagnetism,spin polarization and Curie temperature are estimated from exchange energies analysis.In addition,exchange constants(N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crystal ifeld energy,and double exchange mechanism were studied to explore the magnetic response.Likewise,the electrical conductivity,thermal conductivity,Seebeck co-efficient,and power factor show effect on electrons spin and their potential for thermoelectric devices.展开更多
Large scale cereal farming faces many problems in the West African Sahel. One of the constraints to large-scale cereal production is competition from weeds. The problem of controlling weeds in millet fields is an obst...Large scale cereal farming faces many problems in the West African Sahel. One of the constraints to large-scale cereal production is competition from weeds. The problem of controlling weeds in millet fields is an obstacle to increasing the area sown. In addition to that, there is a scarcity of studies that looked at the impacts of ruderal weed such as legume ruderal weed on the yield of cereal like pearl millet which is of staple food in Niger. The present study, carried out in the Department of Illéla, located in the east-southeast of Niger, aims to determine the density of Cassia mimosoides that can influence millet production. Our experimental design was a randomized Fisher block with four replications. Each block comprises a control and five treatments. Our study focused on measuring certain production parameters, namely millet plant height and yield of millet plants. The tolerant density can be estimated at four Cassia mimosoides plants per square meter. A one factor analysis of variance (ANOVA) was used to compare the production obtained according to the type of treatment at P ≤ 0.05. Beyond this critical value, the weed starts to interfere with the millet from the fifth week onwards (period of interference). The results showed the sensitivity of seedlings under the influence of Cassia mimosoides plants. The best yields were obtained in the control plots (2375 Kg/ha). Millet grain yield decreased with increasing Cassia mimosoides density. Plots with low Cassia mimosoides densities produced more millet (plots with 2 plants/m2 of Cassia mimosoides: T1 = 1500 Kg/ha at P ≤ 0.05) than those with high densities (plots with 20 plants/m2 of Cassia mimosoides: T10 = 168.75 Kg/ha at P ≤ 0.05). The difference in the average yield of pearl millet between the control and the treatment T1 is 875 kg/ha and that of the control and treatment T10 is 2206.25 kg/ha. The results showed that the cycle of reproduction of the local variety “Guèreguera” is 98 days (from July 12, 2023 to October 25, 2023). These findings of this study complete the efforts of developing weed control techniques in pearl millet fields densely populated with Cassia mimosoides.展开更多
The Atlas pistachio tree is a typically Mediterranean species,which represents an important forest heritage in the arid and semi-arid regions of Algeria.It is deeply rooted in the local population’s culture,making it...The Atlas pistachio tree is a typically Mediterranean species,which represents an important forest heritage in the arid and semi-arid regions of Algeria.It is deeply rooted in the local population’s culture,making it essential to better understand this species for its conservation and valorization.Through our work on 7 provenances of Pistacia atlantica distributed across different bioclimates in Algeria and based on 28 quantitative and qualitative leaf,trichome,and stomatal traits,it was revealed that the Atlas pistachio tree exhibits significant ecotypic variability linked to its habitat and a high adaptability to extreme conditions in its environments(aridity and altitude).Indeed,statistical analyses indicate a substantial heterogeneity in the studied characteristics among different ecotypes of P.atlantica.Genetic factors undoubtedly play a primary role in this variability,but environmental factors also exert a remarkable impact on this heterogeneity.Gender also plays a crucial role in this variability.Microphotographs of leaf samples taken under scanning electron microscopy(SEM),such as the density and type of trichomes,and form and position of stomates in the epidermis,can provide an important taxonomic tool for identifying Pistacia species and valuable insights into their adaptation to xeric conditions,thus enabling their use in desertification control projects and the rehabilitation of highly degraded forest environments such as those found in the“Green Dam”initiative.展开更多
Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including at...Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050.展开更多
To address the increasing demand for massive data storage and processing,brain-inspired neuromorphic comput-ing systems based on artificial synaptic devices have been actively developed in recent years.Among the vario...To address the increasing demand for massive data storage and processing,brain-inspired neuromorphic comput-ing systems based on artificial synaptic devices have been actively developed in recent years.Among the various materials inves-tigated for the fabrication of synaptic devices,silicon carbide(SiC)has emerged as a preferred choices due to its high electron mobility,superior thermal conductivity,and excellent thermal stability,which exhibits promising potential for neuromorphic applications in harsh environments.In this review,the recent progress in SiC-based synaptic devices is summarized.Firstly,an in-depth discussion is conducted regarding the categories,working mechanisms,and structural designs of these devices.Subse-quently,several application scenarios for SiC-based synaptic devices are presented.Finally,a few perspectives and directions for their future development are outlined.展开更多
Synthetic fertilizers are widely used to address the urgent challenge of ensuring food supplies for a growing world population in the context of climate change. However, their industrial production and use in agricult...Synthetic fertilizers are widely used to address the urgent challenge of ensuring food supplies for a growing world population in the context of climate change. However, their industrial production and use in agriculture have a negative impact on the environment and consequently on human health. While chemical fertilizers may not have to be abandoned in agricultural production systems, limiting their use could help to make agriculture sustainable and resilient to climate change. In Senegal, the level of mineral fertilizers used in market gardening has become alarming in the Niayes area. As a result, microbial biotechnologies have been promoted for biofertilizer production of common bean (Phaseolus vulgaris L.) cultivation. Rhizobial inoculums have thus been used to reduce the rate of chemical nitrogen fertilizers being applied in cropping systems. Several investigations in the laboratory, on experimental stations and in the field have shown a possibility of a significant reduction in the use of nitrogen fertilizers in common bean production. Conventional mineral fertilization use can be reduced from over 120 kg N/ha to 20 kg N/ha. This contributes both to a very significant reduction in the application rate with the same level of yield and to an improvement in the standard of living. In addition, the environmental impact of using chemical fertilizers can be mitigated. This study is a contribution to the promotion of biofertilizers adoption in agricultural systems.展开更多
Millet [Pennisetum glaucum (L.) R. Br. (Poaceae)] is one of the most widely consumed crops in Niger. Its production, despite the efforts of farmers, is confronted with weed problems, in particular Sesbania pachycarpa ...Millet [Pennisetum glaucum (L.) R. Br. (Poaceae)] is one of the most widely consumed crops in Niger. Its production, despite the efforts of farmers, is confronted with weed problems, in particular Sesbania pachycarpa DC. (Fabaceae). The aim of the present study in this area is to assess the impact of Sesbania pachycarpa on millet growth and yield. To achieve this objective, a completely randomized Fisher block design of twenty-four elementary plots was set up with four replications. The data collected were millet plant heights and plot yields. The data collected were subjected to analysis of variance and Duncan’s test at the 5% threshold for comparisons of mean heights and yields with the control kept clean from sowing to millet harvesting. The results showed the sensitivity of millet plants to Sesbania pachycarpa. The results revealed that the threshold density for damage could be estimated at 6 Sesbania pachycarpa plants/m2 and the critical interference period at the fourth week after sowing. This study showed that the presence of Sesbania pachycarpa influences millet yield. Indeed, the best yields were obtained in plots without Sesbania pachycarpa. Millet yield decreased with increasing Sesbania pachycarpa density. The average percentage yield reduction was 36.79%, with a minimum of 21.25% and a maximum of 80%. The findings of this study complete the efforts of developing weed control techniques in pearl millet fields densely populated with Sesbania pachycarpa.展开更多
N^(6)-Methyladenosine(m^(6)A)is the most common modification in the transcriptome of biological RNA and plays roles that include maintaining the stability and transportation of mRNA,mRNA precursor shearing,polyadenyla...N^(6)-Methyladenosine(m^(6)A)is the most common modification in the transcriptome of biological RNA and plays roles that include maintaining the stability and transportation of mRNA,mRNA precursor shearing,polyadenylation,and the initiation of translation.With the improving understanding of RNA methylation,m^(6)A modification is known to play vital roles in plant development and growth.The multi-petalization of flowering plants has high ornamental and research value in horticultural landscapes.However,the mechanism of RNA methylation in flower formation in Magnolia wufengensis,a classical multi-petalizational plant,remains unclear.This study compared and analyzed RNA m^(6)A methylation and the transcriptome in floral buds of two varieties with large differences in tepal number at the early stage of development.It was found that the degree of RNA m^(6)A methylation and relative expression levels of MawuAGL6-2,MawuPI-4,and MawuAGL9 in‘Jiaodan’with 36 tepals were significantly higher than those in‘Jiaohong’with 9 tepals during the development of floral organ primordia.Combined with quantitative real-time PCR,the expression levels of MawuAGL6-2,MawuPI-4,and MawuAGL9were positively correlated with the number of tepals.Transgenic experiments showed that MawuAGL6-1/2,and MawuPI-4 can increase the number of petals in Arabidopsis.Moreover,MawuAGL6-2 and MawuPI-4 can restore the missing petal phenotype of mutant Arabidopsis.Yeast two hybrid and yeast three hybrid indicated that MawuAGL6-2,MawuAP3-1/2,and MawuPI-4 could interact with each other under the mediation of the class E protein MawuAGL9.Based on these results,it is hypothesized that m^(6)A methylation influences the multi-petalization of Magnolia wufengensis by affecting the expression levels of MawuAGL6-2,MawuAP3-1/2,MawuPI-4,and MawuAGL9.These findings provide a better understanding of the molecular mechanisms of epigenetic modifications in flower developmental diversity.展开更多
The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained expe...The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained experimentally through tests on specimens under multiaxial loading with that calculated by the variance method. In the statistical approach criteria, several methods have been developed but we have presented only one method, namely the variance method using the equivalent stress. She assumes that the fracture plane orientation is the one on which the variance of the equivalent stress is maximum. Three types of equivalent stress are defined for this method [1]: normal stress, shear stress and combined normal and shear stress. The results obtained were compared with experimental results for multiaxial cyclic stress states, and it emerges that the variance method for the case of combined loading is conservative as it gives a better prediction of the fracture plane.展开更多
Introduction: Breastfeeding is the best way to provide ideal nutrition for optimal infant growth and development. Objectives: The aim of our work was to assess the knowledge, attitudes and practices of mothers of chil...Introduction: Breastfeeding is the best way to provide ideal nutrition for optimal infant growth and development. Objectives: The aim of our work was to assess the knowledge, attitudes and practices of mothers of children aged 0 - 24 months on exclusive breastfeeding in the Central African Republic. Methods: This was a cross-sectional, descriptive and analytical study conducted from September 15 to October 15, 2024 among mothers of infants aged 0 to 24 months. Sociodemographic, obstetric and breastfeeding-related data were collected through individual interviews conducted during sensitizations on good feeding practices organized by the Tina Touadera Foundation. The chi2 test was used to test for relationships between variables, and the p significance level was set at 0.05. Results: The average age of the mothers surveyed was 27.67 years. 65.69% (n = 247) of mothers lived in urban areas and 55.85% (n = 210) were Muslim. 56.38% (n = 212) were living common-law and 34.04% (n = 128) were poor. Secondary-school mothers (44.42%, n = 167) and housewives (53.72%, n = 202) were in the majority. Exclusive breastfeeding (EBF) was correctly defined by 79.26% (n = 298) of mothers and actually practised in 24.20% (n = 91) of cases. The main source of information was a health professional in 75.36% (n = 304) of cases. Among the 285 mothers who practised mixed breastfeeding, lack of time (33.33%) was the main reason. They acknowledged having given water (100%), corn porridge (75.09%) and/or artificial milk (24.91%) before the first 6 months of life. The average time for introducing water was 2.2 months, and for porridge/formula 2.79 months. More than half the mothers (55.05%) said they did not know their infants’ weaning age. Factors positively influencing the use of EBF were age under 29, residence in an urban area, primiparity, having been informed about AME by a health professional, and being a housewife or shopkeeper (p Conclusion: Mothers’ level of knowledge was heterogeneous but insufficient overall. An effective system of information and education from pregnancy to the first six months of life is needed to promote breastfeeding.展开更多
Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and act...Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and actuation behaviors have been obtained in either hydrogels or LCEs,they typically undergo reversible shape change only once(e.g.,one expansion plus one contraction)during one heating/cooling cycle.Herein,we report a study of a novel liquid crystalline hydrogel(LCH)and the achievement of dual actuation in a single heating/cooling cycle by integrating the characteristics of thermoresponsive hydrogel and LCE.The dual actuation behavior arises from the reversible volume phase transition of poly(N-isopropylacrylamide)(PNIPAM)and the reversible order-disorder phase transition of LC mesogens in the LCH.Due to a temperature window separating the two transitions belonging to PNIPAM and LCE,LCH actuator can sequentially execute their respective actuation,thus deforming reversibly twice,during a heating/cooling cycle.The relative actuation degree of the two mechanisms is influenced by the mass ratio of PNIPAM to LCE in the LCH.Moreover,the initial shape of a bilayer actuator made with an active LCH layer and a passive polymer layer can be altered through hydration or dehydration of PNIPAM,which further modifies the dual actuation induced deformation.This work provides an example that shows the interest of developing LCH actuators.展开更多
Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods:...Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods: The study used a cross-sectional design and a two-stage cluster sampling method to select participants. The study population was infants aged between 0 - 24 months. Data collection was done between June 2023 and September 2024;it included anthropometric measurements, blood analyses, and interviews. Anthropometric parameters were calculated using ENA for SMART software. Statistical analyses were performed by R Studio to investigate associations between different characteristics, using logistic regression models to identify risk factors. A p-value less than 0.05 was considered significant. Results: The study included 377 infants in eight villages in Guéra Province, Chad. The sample was predominantly girls (55.3%), with a median age of 16 months. Most infants (94%) were mixed-fed, and only 6% were exclusively breastfed. We found that 7.3% of children were globally malnourished, with higher rates in boys 9.6%. A significant disparity existed between boys and girls in global acute malnutrition (GAM) rates, with boys having a higher prevalence of 17.9%. A substantial proportion of Infants were underweight, with males 27.4%. Stunting was prevalent 20.1%. Several factors were associated with malnutrition, including gender, feeding practices, infectious diseases, and socioeconomic factors. Diarrhea, malaria, limited access to drinking water, and early diet diversification were significantly associated with malnutrition. Conclusion: Targeted interventions are necessary to address these issues and improve the nutritional status of children in the Guéra province.展开更多
This study was conducted at the scientific center of Brazzaville. The objective was to assess the microbial characteristics and enzymes activities in the rhizosphere soil of Cajanus cajan and Milletia lauurentii. Thes...This study was conducted at the scientific center of Brazzaville. The objective was to assess the microbial characteristics and enzymes activities in the rhizosphere soil of Cajanus cajan and Milletia lauurentii. These plants have great importance in food and forestry. Microbial diversity management in the rhizosphere is the key for sustainable crop production or forest durability. DNA metagenomic sequencing was used to analyze the whole bacterial diversity, the microbial biomass was determinate by the fumigation-extraction method and the enzymes by the p-nitrophenol-β-D-glucoside for β-glucosidase, the p-nitrophenyl-N-acetyl-β-D-glucosaminide for β-Glucosaminidase. Dehydrogenase and acid phosphatase were quantified using 2,3,5-tryphenyl tetrazolium chloride and p-nitophenylphosphate respectively. The results show that, in Cajanus cajan culturable bacteria genera were mainly Acidobacterium, Skermanella, Rhodoplanes, Bacillus, Chloroflexus, Steroidobacter, Sphingomonas and Bradyrhizobium while in Milletia laurentii: Rhodoplanes, Bradyrhizobium, Bacillus, Sphingobacterium, Acidobacterium, Mesorhizobium, Nitrospira were the principal genera. In the two rhizosphere soils investigated, the uncultured bacteria exhibited relatively higher abundance, often for the same genera, than culturable bacteria. Metagenomic studies have revealed more bacterial diversity in each compared to when culturable bacteria were taken into account alone. The MBC and MBN were higher in the rhizosphere of Milletia than in rhizosphere of Cajanus. The same trend was observed with the enzyme activities. PCA of culturable and NMDS of unculturable soil bacteria genera shows that factors mainly involved in the carbon cycle such as MBC, members of the microbial community i.e. Acidobacterium, Skermanella, Chloroflexus, sand, C, β-glucosaminidase and dehydrogenase, were strongly correlated with Cajanus cajan. On the other hand, the MBN, Mesorhizobium, Bradyrhizobium, Burkholderia, Nitrospira, Nitratireductor, N, NH4, β-glucosidase and acid phosphatase involved in the N cycling, silt and clay were predominantly founded in the rhizosphere soil of Milletia laurentii. This study showed that metagenomic sequencing could improve the assessment of the microbial diversity structure of the rhizosphere.展开更多
Introduction: Work-related accidents constitute are a public health concern worldwide. The aim of our study was to assess a series of work-related accidents that occurred in a cardboard packaging manufacturing company...Introduction: Work-related accidents constitute are a public health concern worldwide. The aim of our study was to assess a series of work-related accidents that occurred in a cardboard packaging manufacturing company in Abidjan from 2012 to 2019 and to determine the consequences for the victims and the company. We’ve carried out a retrospective study of all work-related injuries reported to the National Social Insurance Fund of Cote d’Ivoire from 2012 to 2019 using the company’s work-related accidents’ register and investigation reports. Results: The prevalence of work-related injuries among the workers was 84% for the manual workers and 16% for the supervisors. The trends in the prevalence of work-related injuries were upwards, with a slow and almost linear progression over the period of study. Most of the accidents (53%) occurred in the process area. The upper limbs were the most common location of injuries (46%) and almost all the cases were declared cured. The cumulative direct costs of the TAs over the 8 years were 46,185,533 FCFA, or 70409.39 euros. The average direct annual cost was 624,129 CFA francs, or 951.47 euros. The average annual indirect cost was 41,265,576 CFA francs. The cumulative amount of indirect costs was 330,124,611 CFA francs over the 8 years. The indirect costs accumulated over the 8 years represented 98.17% of the cumulative economic cost of work accidents. Discussion: The assessment of the socioeconomic impact of these work-related injuries revealed that indirect costs which are usually ignored nor underestimated by the employers represent a minimum direct/indirect ratio of 1/27. Conclusion: Prevention is the best option to anticipate or mitigate the impact of work-related accidents among the victims.展开更多
This study examines hemodynamic behavior in particular cases of pulmonary hypertension without treatment. Pulmonary hypertension represents an anomalous hemodynamic state and is characterized by an excessively high bl...This study examines hemodynamic behavior in particular cases of pulmonary hypertension without treatment. Pulmonary hypertension represents an anomalous hemodynamic state and is characterized by an excessively high blood pressure in the pulmonary artery. To simulate the hemodynamic abnormalities in pulmonary hypertension under different causes and pathologies, we construct a localized parameter circuit model governed by nonlinear ordinary derivative equations of the human circulatory system. Thus, two special cases are considered, namely pulmonary the artery stenosis and the left ventricular diastolic dysfunction. For each case of pulmonary hypertension development, we determine the relationships between blood pressure and chamber and vessel pressure-volume. When the pulmonary hypertension is due to pulmonary artery stenosis, it appears that the right ventricular pressure increases up to 90 mm Hg, likewise the rise in pulmonary artery resistance induces direct increment in pulmonary artery pressure. However, when the pulmonary hypertension is due to left ventricular diastolic dysfunction, we note that the left atrial pressure and the pulmonary vein pressure augment, leading to the growth of the pulmonary artery blood pressure. The established results within this paper are useful for understanding the hemodynamic mechanism of particular pulmonary hypertension.展开更多
Cassava is the most widely distributed food crop in Central Africa. Chikwangue, also known as kwanga in the Republic of Congo, is a starchy fermented cassava product that is a staple food in the country. This work aim...Cassava is the most widely distributed food crop in Central Africa. Chikwangue, also known as kwanga in the Republic of Congo, is a starchy fermented cassava product that is a staple food in the country. This work aims to determine the composition of bioactive compounds in chikwangue, including biosurfactant-like molecules and proteins content. Antibacterial activities were investigated through the preliminary emulsification index of chikwangue and fermented paste. Antibacterial assay, 16S rRNA, cytK, hblD, nheB and entFM PCR amplifications, DNA sequence analysis, NCBI homology analysis, and phylogenic tree were performed using NGPhylogeny. fr and iTOL (interactive of live). Fermented cassava paste and chikwangue contain biosurfactants with an emulsification index of 50%. The total protein concentration in fermented cassava paste was 4 g/ml and the chikwangue was 2.5 g/mL Further sequence analysis showed that isolates shared a homology of up to 99.9% with Bacillus cereus PQ432941.1, B. licheniformis PQ432758.1, B. altitudinis PQ432754.1, B. subtilis PQ432759.1, B. mojavensis PQ432755.1, B. tequilensis MT994788.1, B. subtilis MT994789.1, Paenibacillus polymyxa PQ452544.1, B. velezensis PQ452545.1, B. thuringiensis PQ432763.1, B. pumilus PQ432762.1, B. subtilis MT994787.1, B. mycoides PQ432890.1, B. thuringiensis PQ432766.1, B. subtilis PQ432757.1 and B. amyloliquefaciens PQ432756.1. Importantly, the emulsification index (E24) ranged from 60 to 100% and the crude biosurfactant for the Bacillus strains mentioned above could easily inhibit the growth for pathogen Gram-negative bacteria (S. enterica, S. flexneri, E. coli, Klebsiella sp. and P. aeruginosa) with diameters ranging from 2.3 ± 0.1 cm to 5.5 ± 0.4 cm. On the other hand, the diameters of Gram-positive pathogenic bacteria (B. cereus and S. aureus) varied between 1.5 ± 0.5 cm and 4.0 ± 0.2 cm. These findings involve the promise purpose of Bacillus isolated from retted cassava, and this study systematically uncovered the biodiversity and distribution characteristics of retted paste cassava and chikwangue.展开更多
Cowpea, Vigna unguiculata L. Walp, is an important food grain legume in Niger facing production losses due to insect pests. This study aims to determine the efficiency of non-chemical methods for managing these pests....Cowpea, Vigna unguiculata L. Walp, is an important food grain legume in Niger facing production losses due to insect pests. This study aims to determine the efficiency of non-chemical methods for managing these pests. A trial was conducted during the 2020 and 2022 cropping seasons at the INRAN station in the Maradi region. A Fischer experimental design with 6 repetitions was used to compare 4 treatments: synthetic chemical pesticide;the entomopathogenic fungus Beauveria bassiana;aqueous extracts of neem seeds, and control. Observations were carried out every three days. The cowpea pod-sucking bug, pod borer, and thrips were the main insect pests recorded. In terms of effectiveness, the synthetic pesticide was the best treatment. It reduced insect pest densities by 71.35% to 90.40% in 2020 and by 35.11% to 42.13% in 2022. Grain yields varied between treatments. Neem seed extract followed the synthetic pesticide and significantly reduced insect infestations in both years. The synthetic pesticide and neem seed extract resulted in yields 3 to 5 times higher than the control treatment in 2020. By contrast, B. bassiana 115 and neem seed extract produced similar yields in 2022. Therefore, the results of this study showed that B. bassiana 115 and neem seed extract have insecticidal potential and could be used as an ecological alternative for managing cowpea insect pests in the Sahel.展开更多
Background: Pediatric brain tumors (PBT) are among the most common childhood neoplasms worldwide, but their management in low- and middle-income countries (LMICs) remains under-documented. Limited access to specialize...Background: Pediatric brain tumors (PBT) are among the most common childhood neoplasms worldwide, but their management in low- and middle-income countries (LMICs) remains under-documented. Limited access to specialized care, diagnostic tools, and adjuvant therapies poses significant challenges in sub-Saharan Africa, including Togo. Objective: This study reviews the management of pediatric brain tumors in Togo. Methods: We conducted a retrospective study in the neurosurgery department at Sylvanus Olympio Teaching Hospital between November 2017 and December 2022. Demographic, clinical, radiographic, operative, pathology, and outcome data were collected and analyzed. Results: Eighteen patients had histologically verified brain tumors. Ages ranged from 1 to 15 years (mean: 7.73 ± 4.28), with a sex ratio of 1. Symptoms of raised intracranial pressure were present in 83.4% of cases. The mean interval to presentation was 22 ± 5.32 months. Tumors were supratentorial in 66.7% of cases. Total tumor removal was achieved in 61.1%. Astrocytoma was the most common histological diagnosis, followed by ependymoma and medulloblastoma. Five patients (27.8%) died within the first month post-surgery. The estimated 5-year survival rate was 43% ± 5.4%. Conclusion: Delayed diagnosis, insufficient infrastructure, and limited access to radiotherapy and chemotherapy contribute to poor outcomes. Improving neurosurgical capacity, infrastructure, and financial support could enhance survival and outcomes for pediatric brain tumor patients in Togo.展开更多
文摘This paper introduces a novel variant of particle swarm optimization that leverages local displacements through attractors for addressing multiobjective optimization problems. The method incorporates a square root distance mechanism into the external archives to enhance the diversity. We evaluate the performance of the proposed approach on a set of constrained and unconstrained multiobjective test functions, establishing a benchmark for comparison. In order to gauge its effectiveness relative to established techniques, we conduct a comprehensive comparison with well-known approaches such as SMPSO, NSGA2 and SPEA2. The numerical results demonstrate that our method not only achieves efficiency but also exhibits competitiveness when compared to evolutionary algorithms. Particularly noteworthy is its superior performance in terms of convergence and diversification, surpassing the capabilities of its predecessors.
基金funded by the Princess Nourah bint Abdulrahman University Researchers Supporting Project(PNURSP2023R29)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabiathe Deanship of Scientific Research at King Khalid University,SaudiArabia for funding this work through Large Groups Project(L.R.G.P2/431/44)。
文摘In current report,the structural,magnetic,and thermoelectric properties of RE doped MgPm_(2)X_(4)(X=S,Se) spinels were investigated.The energy difference in ferromagnetic and antiferromagnetic states reveals the stability of MgPm_(2)(S/Se)_(4) in the ferromagnetic states.The co mputation of enthalpy of formation also ascertains thermodynamic stability of crystal structure.Spin-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin channels.The room temperature ferromagnetism,spin polarization and Curie temperature are estimated from exchange energies analysis.In addition,exchange constants(N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crystal ifeld energy,and double exchange mechanism were studied to explore the magnetic response.Likewise,the electrical conductivity,thermal conductivity,Seebeck co-efficient,and power factor show effect on electrons spin and their potential for thermoelectric devices.
文摘Large scale cereal farming faces many problems in the West African Sahel. One of the constraints to large-scale cereal production is competition from weeds. The problem of controlling weeds in millet fields is an obstacle to increasing the area sown. In addition to that, there is a scarcity of studies that looked at the impacts of ruderal weed such as legume ruderal weed on the yield of cereal like pearl millet which is of staple food in Niger. The present study, carried out in the Department of Illéla, located in the east-southeast of Niger, aims to determine the density of Cassia mimosoides that can influence millet production. Our experimental design was a randomized Fisher block with four replications. Each block comprises a control and five treatments. Our study focused on measuring certain production parameters, namely millet plant height and yield of millet plants. The tolerant density can be estimated at four Cassia mimosoides plants per square meter. A one factor analysis of variance (ANOVA) was used to compare the production obtained according to the type of treatment at P ≤ 0.05. Beyond this critical value, the weed starts to interfere with the millet from the fifth week onwards (period of interference). The results showed the sensitivity of seedlings under the influence of Cassia mimosoides plants. The best yields were obtained in the control plots (2375 Kg/ha). Millet grain yield decreased with increasing Cassia mimosoides density. Plots with low Cassia mimosoides densities produced more millet (plots with 2 plants/m2 of Cassia mimosoides: T1 = 1500 Kg/ha at P ≤ 0.05) than those with high densities (plots with 20 plants/m2 of Cassia mimosoides: T10 = 168.75 Kg/ha at P ≤ 0.05). The difference in the average yield of pearl millet between the control and the treatment T1 is 875 kg/ha and that of the control and treatment T10 is 2206.25 kg/ha. The results showed that the cycle of reproduction of the local variety “Guèreguera” is 98 days (from July 12, 2023 to October 25, 2023). These findings of this study complete the efforts of developing weed control techniques in pearl millet fields densely populated with Cassia mimosoides.
基金their appreciation to the Researchers Supporting Project number(RSP2024R390)King Saud University,Riyadh,Saudi Arabia and la Direction Générale de la Recherche Scientifique et du Développement Technologique(DGRSDT),Algeria.
文摘The Atlas pistachio tree is a typically Mediterranean species,which represents an important forest heritage in the arid and semi-arid regions of Algeria.It is deeply rooted in the local population’s culture,making it essential to better understand this species for its conservation and valorization.Through our work on 7 provenances of Pistacia atlantica distributed across different bioclimates in Algeria and based on 28 quantitative and qualitative leaf,trichome,and stomatal traits,it was revealed that the Atlas pistachio tree exhibits significant ecotypic variability linked to its habitat and a high adaptability to extreme conditions in its environments(aridity and altitude).Indeed,statistical analyses indicate a substantial heterogeneity in the studied characteristics among different ecotypes of P.atlantica.Genetic factors undoubtedly play a primary role in this variability,but environmental factors also exert a remarkable impact on this heterogeneity.Gender also plays a crucial role in this variability.Microphotographs of leaf samples taken under scanning electron microscopy(SEM),such as the density and type of trichomes,and form and position of stomates in the epidermis,can provide an important taxonomic tool for identifying Pistacia species and valuable insights into their adaptation to xeric conditions,thus enabling their use in desertification control projects and the rehabilitation of highly degraded forest environments such as those found in the“Green Dam”initiative.
基金supported by the Basic Science Center Project of the National Natural Science Foundation of China(42388102)the National Natural Science Foundation of China(42174030)+2 种基金the Special Fund of Hubei Luojia Laboratory(220100020)the Major Science and Technology Program for Hubei Province(2022AAA002)the Fundamental Research Funds for the Central Universities of China(2042022dx0001 and 2042023kfyq01)。
文摘Nonlinear variations in the coordinate time series of global navigation satellite system(GNSS) reference stations are strongly correlated with surface displacements caused by environmental loading effects,including atmospheric, hydrological, and nontidal ocean loading. Continuous improvements in the accuracy of surface mass loading products, performance of Earth models, and precise data-processing technologies have significantly advanced research on the effects of environmental loading on nonlinear variations in GNSS coordinate time series. However, owing to theoretical limitations, the lack of high spatiotemporal resolution surface mass observations, and the coupling of GNSS technology-related systematic errors, environmental loading and nonlinear GNSS reference station displacements remain inconsistent. The applicability and capability of these loading products across different regions also require further evaluation. This paper outlines methods for modeling environmental loading, surface mass loading products, and service organizations. In addition, it summarizes recent advances in applying environmental loading to address nonlinear variations in global and regional GNSS coordinate time series. Moreover, the scientific questions of existing studies are summarized, and insights into future research directions are provided. The complex nonlinear motion of reference stations is a major factor limiting the accuracy of the current terrestrial reference frame. Further refining the environmental load modeling method, establishing a surface mass distribution model with high spatiotemporal resolution and reliability, exploring other environmental load factors such as ice sheet and artificial mass-change effects, and developing an optimal data-processing model and strategy for reprocessing global reference station data consistently could contribute to the development of a millimeter-level nonlinear motion model for GNSS reference stations with actual physical significance and provide theoretical support for establishing a terrestrial reference frame with 1 mm accuracy by 2050.
基金supported by the Natural Science Foundation of Zhejiang Province(Grant No.LQ24F040007)the National Natural Science Foundation of China(Grant No.U22A2075)the Opening Project of State Key Laboratory of Polymer Materials Engineering(Sichuan University)(Grant No.sklpme2024-1-21).
文摘To address the increasing demand for massive data storage and processing,brain-inspired neuromorphic comput-ing systems based on artificial synaptic devices have been actively developed in recent years.Among the various materials inves-tigated for the fabrication of synaptic devices,silicon carbide(SiC)has emerged as a preferred choices due to its high electron mobility,superior thermal conductivity,and excellent thermal stability,which exhibits promising potential for neuromorphic applications in harsh environments.In this review,the recent progress in SiC-based synaptic devices is summarized.Firstly,an in-depth discussion is conducted regarding the categories,working mechanisms,and structural designs of these devices.Subse-quently,several application scenarios for SiC-based synaptic devices are presented.Finally,a few perspectives and directions for their future development are outlined.
文摘Synthetic fertilizers are widely used to address the urgent challenge of ensuring food supplies for a growing world population in the context of climate change. However, their industrial production and use in agriculture have a negative impact on the environment and consequently on human health. While chemical fertilizers may not have to be abandoned in agricultural production systems, limiting their use could help to make agriculture sustainable and resilient to climate change. In Senegal, the level of mineral fertilizers used in market gardening has become alarming in the Niayes area. As a result, microbial biotechnologies have been promoted for biofertilizer production of common bean (Phaseolus vulgaris L.) cultivation. Rhizobial inoculums have thus been used to reduce the rate of chemical nitrogen fertilizers being applied in cropping systems. Several investigations in the laboratory, on experimental stations and in the field have shown a possibility of a significant reduction in the use of nitrogen fertilizers in common bean production. Conventional mineral fertilization use can be reduced from over 120 kg N/ha to 20 kg N/ha. This contributes both to a very significant reduction in the application rate with the same level of yield and to an improvement in the standard of living. In addition, the environmental impact of using chemical fertilizers can be mitigated. This study is a contribution to the promotion of biofertilizers adoption in agricultural systems.
文摘Millet [Pennisetum glaucum (L.) R. Br. (Poaceae)] is one of the most widely consumed crops in Niger. Its production, despite the efforts of farmers, is confronted with weed problems, in particular Sesbania pachycarpa DC. (Fabaceae). The aim of the present study in this area is to assess the impact of Sesbania pachycarpa on millet growth and yield. To achieve this objective, a completely randomized Fisher block design of twenty-four elementary plots was set up with four replications. The data collected were millet plant heights and plot yields. The data collected were subjected to analysis of variance and Duncan’s test at the 5% threshold for comparisons of mean heights and yields with the control kept clean from sowing to millet harvesting. The results showed the sensitivity of millet plants to Sesbania pachycarpa. The results revealed that the threshold density for damage could be estimated at 6 Sesbania pachycarpa plants/m2 and the critical interference period at the fourth week after sowing. This study showed that the presence of Sesbania pachycarpa influences millet yield. Indeed, the best yields were obtained in plots without Sesbania pachycarpa. Millet yield decreased with increasing Sesbania pachycarpa density. The average percentage yield reduction was 36.79%, with a minimum of 21.25% and a maximum of 80%. The findings of this study complete the efforts of developing weed control techniques in pearl millet fields densely populated with Sesbania pachycarpa.
基金supported by the National Natural Science Foundation of China(Grant No.31570651)。
文摘N^(6)-Methyladenosine(m^(6)A)is the most common modification in the transcriptome of biological RNA and plays roles that include maintaining the stability and transportation of mRNA,mRNA precursor shearing,polyadenylation,and the initiation of translation.With the improving understanding of RNA methylation,m^(6)A modification is known to play vital roles in plant development and growth.The multi-petalization of flowering plants has high ornamental and research value in horticultural landscapes.However,the mechanism of RNA methylation in flower formation in Magnolia wufengensis,a classical multi-petalizational plant,remains unclear.This study compared and analyzed RNA m^(6)A methylation and the transcriptome in floral buds of two varieties with large differences in tepal number at the early stage of development.It was found that the degree of RNA m^(6)A methylation and relative expression levels of MawuAGL6-2,MawuPI-4,and MawuAGL9 in‘Jiaodan’with 36 tepals were significantly higher than those in‘Jiaohong’with 9 tepals during the development of floral organ primordia.Combined with quantitative real-time PCR,the expression levels of MawuAGL6-2,MawuPI-4,and MawuAGL9were positively correlated with the number of tepals.Transgenic experiments showed that MawuAGL6-1/2,and MawuPI-4 can increase the number of petals in Arabidopsis.Moreover,MawuAGL6-2 and MawuPI-4 can restore the missing petal phenotype of mutant Arabidopsis.Yeast two hybrid and yeast three hybrid indicated that MawuAGL6-2,MawuAP3-1/2,and MawuPI-4 could interact with each other under the mediation of the class E protein MawuAGL9.Based on these results,it is hypothesized that m^(6)A methylation influences the multi-petalization of Magnolia wufengensis by affecting the expression levels of MawuAGL6-2,MawuAP3-1/2,MawuPI-4,and MawuAGL9.These findings provide a better understanding of the molecular mechanisms of epigenetic modifications in flower developmental diversity.
文摘The prediction of the fracture plane orientation in fatigue is a scientific topic and remains relevant for every type of material. However, in this work, we compared the orientation of the fracture plane obtained experimentally through tests on specimens under multiaxial loading with that calculated by the variance method. In the statistical approach criteria, several methods have been developed but we have presented only one method, namely the variance method using the equivalent stress. She assumes that the fracture plane orientation is the one on which the variance of the equivalent stress is maximum. Three types of equivalent stress are defined for this method [1]: normal stress, shear stress and combined normal and shear stress. The results obtained were compared with experimental results for multiaxial cyclic stress states, and it emerges that the variance method for the case of combined loading is conservative as it gives a better prediction of the fracture plane.
文摘Introduction: Breastfeeding is the best way to provide ideal nutrition for optimal infant growth and development. Objectives: The aim of our work was to assess the knowledge, attitudes and practices of mothers of children aged 0 - 24 months on exclusive breastfeeding in the Central African Republic. Methods: This was a cross-sectional, descriptive and analytical study conducted from September 15 to October 15, 2024 among mothers of infants aged 0 to 24 months. Sociodemographic, obstetric and breastfeeding-related data were collected through individual interviews conducted during sensitizations on good feeding practices organized by the Tina Touadera Foundation. The chi2 test was used to test for relationships between variables, and the p significance level was set at 0.05. Results: The average age of the mothers surveyed was 27.67 years. 65.69% (n = 247) of mothers lived in urban areas and 55.85% (n = 210) were Muslim. 56.38% (n = 212) were living common-law and 34.04% (n = 128) were poor. Secondary-school mothers (44.42%, n = 167) and housewives (53.72%, n = 202) were in the majority. Exclusive breastfeeding (EBF) was correctly defined by 79.26% (n = 298) of mothers and actually practised in 24.20% (n = 91) of cases. The main source of information was a health professional in 75.36% (n = 304) of cases. Among the 285 mothers who practised mixed breastfeeding, lack of time (33.33%) was the main reason. They acknowledged having given water (100%), corn porridge (75.09%) and/or artificial milk (24.91%) before the first 6 months of life. The average time for introducing water was 2.2 months, and for porridge/formula 2.79 months. More than half the mothers (55.05%) said they did not know their infants’ weaning age. Factors positively influencing the use of EBF were age under 29, residence in an urban area, primiparity, having been informed about AME by a health professional, and being a housewife or shopkeeper (p Conclusion: Mothers’ level of knowledge was heterogeneous but insufficient overall. An effective system of information and education from pregnancy to the first six months of life is needed to promote breastfeeding.
基金financial support from the Natural Sciences and Engineering Research Council of Canada(NSERC),le Fonds de recherche du Québec:Nature et technologies(FRQNT),and The Centre québécois sur les matériaux fonctionnels.
文摘Stimuli-responsive shape-changing materials,particularly hydrogel and liquid crystal elastomer(LCE),have demonstrated significant potential for applications across various fields.Although intricate deformation and actuation behaviors have been obtained in either hydrogels or LCEs,they typically undergo reversible shape change only once(e.g.,one expansion plus one contraction)during one heating/cooling cycle.Herein,we report a study of a novel liquid crystalline hydrogel(LCH)and the achievement of dual actuation in a single heating/cooling cycle by integrating the characteristics of thermoresponsive hydrogel and LCE.The dual actuation behavior arises from the reversible volume phase transition of poly(N-isopropylacrylamide)(PNIPAM)and the reversible order-disorder phase transition of LC mesogens in the LCH.Due to a temperature window separating the two transitions belonging to PNIPAM and LCE,LCH actuator can sequentially execute their respective actuation,thus deforming reversibly twice,during a heating/cooling cycle.The relative actuation degree of the two mechanisms is influenced by the mass ratio of PNIPAM to LCE in the LCH.Moreover,the initial shape of a bilayer actuator made with an active LCH layer and a passive polymer layer can be altered through hydration or dehydration of PNIPAM,which further modifies the dual actuation induced deformation.This work provides an example that shows the interest of developing LCH actuators.
文摘Background: Malnutrition, a serious public health concern, is influenced by various factors. Objective: The study aims to explore malnutrition issues among infants under five years old in Guéra Province. Methods: The study used a cross-sectional design and a two-stage cluster sampling method to select participants. The study population was infants aged between 0 - 24 months. Data collection was done between June 2023 and September 2024;it included anthropometric measurements, blood analyses, and interviews. Anthropometric parameters were calculated using ENA for SMART software. Statistical analyses were performed by R Studio to investigate associations between different characteristics, using logistic regression models to identify risk factors. A p-value less than 0.05 was considered significant. Results: The study included 377 infants in eight villages in Guéra Province, Chad. The sample was predominantly girls (55.3%), with a median age of 16 months. Most infants (94%) were mixed-fed, and only 6% were exclusively breastfed. We found that 7.3% of children were globally malnourished, with higher rates in boys 9.6%. A significant disparity existed between boys and girls in global acute malnutrition (GAM) rates, with boys having a higher prevalence of 17.9%. A substantial proportion of Infants were underweight, with males 27.4%. Stunting was prevalent 20.1%. Several factors were associated with malnutrition, including gender, feeding practices, infectious diseases, and socioeconomic factors. Diarrhea, malaria, limited access to drinking water, and early diet diversification were significantly associated with malnutrition. Conclusion: Targeted interventions are necessary to address these issues and improve the nutritional status of children in the Guéra province.
文摘This study was conducted at the scientific center of Brazzaville. The objective was to assess the microbial characteristics and enzymes activities in the rhizosphere soil of Cajanus cajan and Milletia lauurentii. These plants have great importance in food and forestry. Microbial diversity management in the rhizosphere is the key for sustainable crop production or forest durability. DNA metagenomic sequencing was used to analyze the whole bacterial diversity, the microbial biomass was determinate by the fumigation-extraction method and the enzymes by the p-nitrophenol-β-D-glucoside for β-glucosidase, the p-nitrophenyl-N-acetyl-β-D-glucosaminide for β-Glucosaminidase. Dehydrogenase and acid phosphatase were quantified using 2,3,5-tryphenyl tetrazolium chloride and p-nitophenylphosphate respectively. The results show that, in Cajanus cajan culturable bacteria genera were mainly Acidobacterium, Skermanella, Rhodoplanes, Bacillus, Chloroflexus, Steroidobacter, Sphingomonas and Bradyrhizobium while in Milletia laurentii: Rhodoplanes, Bradyrhizobium, Bacillus, Sphingobacterium, Acidobacterium, Mesorhizobium, Nitrospira were the principal genera. In the two rhizosphere soils investigated, the uncultured bacteria exhibited relatively higher abundance, often for the same genera, than culturable bacteria. Metagenomic studies have revealed more bacterial diversity in each compared to when culturable bacteria were taken into account alone. The MBC and MBN were higher in the rhizosphere of Milletia than in rhizosphere of Cajanus. The same trend was observed with the enzyme activities. PCA of culturable and NMDS of unculturable soil bacteria genera shows that factors mainly involved in the carbon cycle such as MBC, members of the microbial community i.e. Acidobacterium, Skermanella, Chloroflexus, sand, C, β-glucosaminidase and dehydrogenase, were strongly correlated with Cajanus cajan. On the other hand, the MBN, Mesorhizobium, Bradyrhizobium, Burkholderia, Nitrospira, Nitratireductor, N, NH4, β-glucosidase and acid phosphatase involved in the N cycling, silt and clay were predominantly founded in the rhizosphere soil of Milletia laurentii. This study showed that metagenomic sequencing could improve the assessment of the microbial diversity structure of the rhizosphere.
文摘Introduction: Work-related accidents constitute are a public health concern worldwide. The aim of our study was to assess a series of work-related accidents that occurred in a cardboard packaging manufacturing company in Abidjan from 2012 to 2019 and to determine the consequences for the victims and the company. We’ve carried out a retrospective study of all work-related injuries reported to the National Social Insurance Fund of Cote d’Ivoire from 2012 to 2019 using the company’s work-related accidents’ register and investigation reports. Results: The prevalence of work-related injuries among the workers was 84% for the manual workers and 16% for the supervisors. The trends in the prevalence of work-related injuries were upwards, with a slow and almost linear progression over the period of study. Most of the accidents (53%) occurred in the process area. The upper limbs were the most common location of injuries (46%) and almost all the cases were declared cured. The cumulative direct costs of the TAs over the 8 years were 46,185,533 FCFA, or 70409.39 euros. The average direct annual cost was 624,129 CFA francs, or 951.47 euros. The average annual indirect cost was 41,265,576 CFA francs. The cumulative amount of indirect costs was 330,124,611 CFA francs over the 8 years. The indirect costs accumulated over the 8 years represented 98.17% of the cumulative economic cost of work accidents. Discussion: The assessment of the socioeconomic impact of these work-related injuries revealed that indirect costs which are usually ignored nor underestimated by the employers represent a minimum direct/indirect ratio of 1/27. Conclusion: Prevention is the best option to anticipate or mitigate the impact of work-related accidents among the victims.
文摘This study examines hemodynamic behavior in particular cases of pulmonary hypertension without treatment. Pulmonary hypertension represents an anomalous hemodynamic state and is characterized by an excessively high blood pressure in the pulmonary artery. To simulate the hemodynamic abnormalities in pulmonary hypertension under different causes and pathologies, we construct a localized parameter circuit model governed by nonlinear ordinary derivative equations of the human circulatory system. Thus, two special cases are considered, namely pulmonary the artery stenosis and the left ventricular diastolic dysfunction. For each case of pulmonary hypertension development, we determine the relationships between blood pressure and chamber and vessel pressure-volume. When the pulmonary hypertension is due to pulmonary artery stenosis, it appears that the right ventricular pressure increases up to 90 mm Hg, likewise the rise in pulmonary artery resistance induces direct increment in pulmonary artery pressure. However, when the pulmonary hypertension is due to left ventricular diastolic dysfunction, we note that the left atrial pressure and the pulmonary vein pressure augment, leading to the growth of the pulmonary artery blood pressure. The established results within this paper are useful for understanding the hemodynamic mechanism of particular pulmonary hypertension.
文摘Cassava is the most widely distributed food crop in Central Africa. Chikwangue, also known as kwanga in the Republic of Congo, is a starchy fermented cassava product that is a staple food in the country. This work aims to determine the composition of bioactive compounds in chikwangue, including biosurfactant-like molecules and proteins content. Antibacterial activities were investigated through the preliminary emulsification index of chikwangue and fermented paste. Antibacterial assay, 16S rRNA, cytK, hblD, nheB and entFM PCR amplifications, DNA sequence analysis, NCBI homology analysis, and phylogenic tree were performed using NGPhylogeny. fr and iTOL (interactive of live). Fermented cassava paste and chikwangue contain biosurfactants with an emulsification index of 50%. The total protein concentration in fermented cassava paste was 4 g/ml and the chikwangue was 2.5 g/mL Further sequence analysis showed that isolates shared a homology of up to 99.9% with Bacillus cereus PQ432941.1, B. licheniformis PQ432758.1, B. altitudinis PQ432754.1, B. subtilis PQ432759.1, B. mojavensis PQ432755.1, B. tequilensis MT994788.1, B. subtilis MT994789.1, Paenibacillus polymyxa PQ452544.1, B. velezensis PQ452545.1, B. thuringiensis PQ432763.1, B. pumilus PQ432762.1, B. subtilis MT994787.1, B. mycoides PQ432890.1, B. thuringiensis PQ432766.1, B. subtilis PQ432757.1 and B. amyloliquefaciens PQ432756.1. Importantly, the emulsification index (E24) ranged from 60 to 100% and the crude biosurfactant for the Bacillus strains mentioned above could easily inhibit the growth for pathogen Gram-negative bacteria (S. enterica, S. flexneri, E. coli, Klebsiella sp. and P. aeruginosa) with diameters ranging from 2.3 ± 0.1 cm to 5.5 ± 0.4 cm. On the other hand, the diameters of Gram-positive pathogenic bacteria (B. cereus and S. aureus) varied between 1.5 ± 0.5 cm and 4.0 ± 0.2 cm. These findings involve the promise purpose of Bacillus isolated from retted cassava, and this study systematically uncovered the biodiversity and distribution characteristics of retted paste cassava and chikwangue.
文摘Cowpea, Vigna unguiculata L. Walp, is an important food grain legume in Niger facing production losses due to insect pests. This study aims to determine the efficiency of non-chemical methods for managing these pests. A trial was conducted during the 2020 and 2022 cropping seasons at the INRAN station in the Maradi region. A Fischer experimental design with 6 repetitions was used to compare 4 treatments: synthetic chemical pesticide;the entomopathogenic fungus Beauveria bassiana;aqueous extracts of neem seeds, and control. Observations were carried out every three days. The cowpea pod-sucking bug, pod borer, and thrips were the main insect pests recorded. In terms of effectiveness, the synthetic pesticide was the best treatment. It reduced insect pest densities by 71.35% to 90.40% in 2020 and by 35.11% to 42.13% in 2022. Grain yields varied between treatments. Neem seed extract followed the synthetic pesticide and significantly reduced insect infestations in both years. The synthetic pesticide and neem seed extract resulted in yields 3 to 5 times higher than the control treatment in 2020. By contrast, B. bassiana 115 and neem seed extract produced similar yields in 2022. Therefore, the results of this study showed that B. bassiana 115 and neem seed extract have insecticidal potential and could be used as an ecological alternative for managing cowpea insect pests in the Sahel.
文摘Background: Pediatric brain tumors (PBT) are among the most common childhood neoplasms worldwide, but their management in low- and middle-income countries (LMICs) remains under-documented. Limited access to specialized care, diagnostic tools, and adjuvant therapies poses significant challenges in sub-Saharan Africa, including Togo. Objective: This study reviews the management of pediatric brain tumors in Togo. Methods: We conducted a retrospective study in the neurosurgery department at Sylvanus Olympio Teaching Hospital between November 2017 and December 2022. Demographic, clinical, radiographic, operative, pathology, and outcome data were collected and analyzed. Results: Eighteen patients had histologically verified brain tumors. Ages ranged from 1 to 15 years (mean: 7.73 ± 4.28), with a sex ratio of 1. Symptoms of raised intracranial pressure were present in 83.4% of cases. The mean interval to presentation was 22 ± 5.32 months. Tumors were supratentorial in 66.7% of cases. Total tumor removal was achieved in 61.1%. Astrocytoma was the most common histological diagnosis, followed by ependymoma and medulloblastoma. Five patients (27.8%) died within the first month post-surgery. The estimated 5-year survival rate was 43% ± 5.4%. Conclusion: Delayed diagnosis, insufficient infrastructure, and limited access to radiotherapy and chemotherapy contribute to poor outcomes. Improving neurosurgical capacity, infrastructure, and financial support could enhance survival and outcomes for pediatric brain tumor patients in Togo.