Lifestyle Habits and Dietary Diversity among Medical Students at Université Gaston Berger (UGB) of Saint-Louis in 2023

Introduction: At university, habits, particularly eating habits, can negatively impact well-being. This study aimed to describe lifestyle habits and dietary diversity among medical students. Methodology: This was a cross-sectional, descriptive study, carried out at the UFR 2S of the University Gaston Berger from May 23 to June 3, 2023. The collection tool focused on sociodemographic characteristics, lifestyle habits and dietary diversity. Statistical analyzes were carried out using R software. Results: A total of 471 students participated in this study. Which corresponds to a participation rate of 89.2% with a M/F sex ratio of 1.66. The age of participants, varying from 18 to 32 years, had a median of 23 years and a mean of 22.4 years with a standard deviation of 2.2 years. Among the participants, 67.2% skipped breakfast, and 28.5% did not practice any physical sports activity. Alcohol and tobacco were consumed by 2.5% and 0.6% of participants, respectively. The most consumed foods were starchy foods (97.5% of men and 98.4% of women);and the least consumed were dark green leafy vegetables (21.9% of men and 15.1% of women) and offal (16.9% of men and 11.9% of women). The dietary diversity score was low for 31.9% of men and 28.7% of women. Conclusion: Certain lifestyle habits (skipping breakfast, dining late at night, lack of sports practice) of Medicine students at UGB can prove deleterious to their well-being. These students are at risk of developing several deficiencies in terms of food groups that are underrepresented in their diet. Awareness sessions on good lifestyle habits and diet would be relevant recommendations for improving the health of these students.

Iodine 131 Treatment in Graves’ Disease in a West African Country: Preliminary Study about 25 Cases in Senegal

Introduction: Graves’ disease is the most common cause of hyperthyroidism. Its treatment uses synthetic antithyroid drugs but the use of aggressive radical therapy such as surgery or non-aggressive therapy such as iodine-131 is not uncommon. Treatment of Graves’ disease with radioactive iodine or iratherapy is a simple, inexpensive, well-tolerated treatment. It was introduced in Senegal in 2016. We report through this work the preliminary assessment of the only nuclear medicine service in Senegal in the management of Graves’ disease by iodine-131. Patients and Methods: Retrospective study of the first cases of Graves’ disease treated with iratherapy in Senegal. Socio-demographic, clinical, paraclinical, therapeutic and evolutionary aspects were studied. Radiation protection rules have been implemented and contraception has been effective for six months in women of childbearing age. Results: 25 patients were collected with a mean age of 45 years, twenty women (80%), a family goiter in 24% and a psycho-affective context in 64% of cases. Thyrotoxicosis syndrome was associated with goiter in 68% of patients and exophthalmos in 64%. Thyroid ultrasound performed in 20 patients showed vascular goiter in 80% and thyroid scintigraphy in 3 patients, homogeneous and diffuse hyperfixation. TRAK dosed in 8 patients was still positive. All patients had received first-line medical treatment. The average duration of this treatment was more than 18 months in 92%. The empirically used iodine-131 activity averaged 15.35 mCi. Oral corticosteroid therapy was prescribed in 7 patients for the prevention of malignant orbitopathy. No early side effects were noted. The remission rate at 3 months was 52% and at 6 months was 88% to 92%. Conclusion: The effectiveness of radioactive iodine, in particular ablative doses in the treatment of hyperthyroidism, is no longer to be demonstrated. Taking into account our socioeconomic context, iratherapy should be a treatment of choice for hyperthyroidism with a good quality/price ratio and excellent tolerance.

Humoral Response and Tolerance of Vaccination against SARS-CoV-2 in Adults Senegalese Patients Undergoing Hemodialysis: A Multicenter Prospective Study

Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to assess the immunological response to vaccination in Senegalese hemodialysis patients. Patients and Methods: We conducted a prospective study, in two dialysis centers in Dakar from March 30th to August 30th, 2021 including patients on hemodialysis for >6 months, vaccinated against SARS-CoV-2 according to the vaccination schedule recommended by WHO. A vaccine response was considered positive when seroconversion was observed after one dose of vaccine. The clinical efficacy of immunization was defined as the absence of new COVID-19 infection in patients who received a complete vaccination. Results: Among the 81 patients included in the study, 7.4% had anti-Spike IgM antibodies before their first vaccination. Seroprevalence of IgM antibodies was 38.3% one month after the first vaccine dose (at M1) and 8.6% one month after the second dose (at M4). Anti-Spike IgG antibodies were present in 40.3% of patients before vaccination, in 90.1% at M1, and in 59.7% at M4. Among patients previously infected with SARS-CoV-2, 10.2% had IgM antibodies at M0, 31.6% at M1, and 10.5% at M4 post-vaccination. Similarly, seroprevalences of IgG antibodies in this subgroup were 31.5%, 61.3%, and 50.0% respectively at M0, M1, and M4 post-vaccination. A comparison of seroconversion rates between M0 and M4 showed significant differences only for IgG in COVID-19 naive patients. Mean duration in dialysis and the existence of previous COVID-19 infection were associated with patients’ vaccinal response after the two doses. Age, gender and the use of immunosuppressive treatment did not influence post-vaccinal antibody production. Conclusion: Vaccination against COVID-19 in Senegalese hemodialysis patients induced a low seroconversion rate but it was well tolerated. Moreover, the induced protection was neither strong nor durable, particularly in patients with longer duration in dialysis.

Consumers’ Perception and Knowledge of Food Additives in Senegal: A Pilot Study

Food safety has become a major concern for consumers, as well as a priority for regulatory authorities. Faced with the growing industrial and domestic use of food additives, many questions are being asked and concerns are being felt by consumers around the world. Consumer perception defines the acceptability or rejection of food products, and has an impact on consumption patterns and behavior. To assess the level of knowledge and perception of food additives, a pilot study was carried out on a sample of 200 people in Dakar and Saint-Louis. A questionnaire was used to assess the acceptance or rejection, use and impact of food additives by consumers in Senegal. The results revealed several aspects. On the whole, the people surveyed expressed great mistrust and even rejection of these substances added to food products. This consumer perception is shared throughout the world, as indicated in numerous surveys. It also emerges from this study that, although most consumers are aware of the existence of these additives and their uses in the home, they feel that the use of these substances in industrial production is too excessive. What’s more, consumers associate food additives with numerous pathologies such as cancer, diabetes, hypertension, stroke and even sexual impotence. For some of these indexed pathologies, scientific studies have reached the same conclusions, although controversy still persists. On the other hand, for some of the other adverse effects mentioned, no cause-and-effect relationship has been scientifically demonstrated. In these latter cases, it seems that negative communication, misinformation and misconceptions have a major influence on consumer perception of food additives.

Identification of Antioxidant Additives in Food Products Sold in Dakar Markets

The use of food additives in industrial production has the advantage of improving sensory properties, technological quality and extending the shelf life of foods. Among the most widely used additives are antioxidants, which prevent oxidation, browning and rancidity reactions in foods. However, the strong presence of these additives on the market is not without risks for human health, and should be controlled to guarantee food safety. Analysis of the risks associated with consumption of foods containing these additives requires, among other things, information on the frequency of use of these additives in various consumer products. The aim of this study is therefore to identify the antioxidants present in industrial food products distributed in Dakar. The methodology adopted consists of a qualitative analysis based on the identification of additives from food labels. Investigations were carried out in 9 stores, 4 superettes and 2 supermarkets located in different districts of Dakar. The results revealed the presence of 12 antioxidant additives, dominated by citric acid (53%) and ascorbic acid (29%). These studies have also highlighted the simultaneous use of several antioxidants in the same food product. Moreover, for some artificial antioxidants identified antioxydant such as BHA and BHT, health risks are associated with their consumption. The results of this study open up prospects for the development of information databases on food additives.

Acute Toxicity and Anthelmintic Effects of Gomphrena serrata L. (Amaranthaceae) Extracts on Adult Worms and Eggs of Haemonchus contortus

Gomphrena serrata L. (Amaranthaceae) is a medicinal plant widely used traditionally in rural areas to treat many diseases, including gastrointestinal helminthiasis of small ruminants. This work aims to estimate the plant extracts phytochemical potential and study the activities of the aqueous decoction (GS_AD), aqueous macerate (GS_AM), and hydroalcoholic macerate (GS_HEM) of Gomphrena serrata extracts on two developmental stages (eggs and adult worms) of Haemonchus contortus. Phytochemical screening was carried out. The acute toxicity test was performed according to the Organisation for Economic Co-operation and Development (OECD) test guideline 423. The Haemonchus contortus eggs hatching inhibition test was performed left to incubate for 48 hours in the presence of the different plant extracts at increasing concentrations of 0.125;0.25;0.5;0.625;1;2;3 mg/mL. For the motility inhibition test on adult worms, the worms were contacted with the extracts at concentrations of 0.75;1;1.25;1.5;2;3;4 mg/mL and left to incubate for 24 hours. Albendazole and levamisole were used as standard. Phytochemical screening revealed the presence of tannins, saponins, reducing compounds, coumarins and derivatives, anthocyanins, steroids, triterpenes, and flavonoids. An acute toxicity study showed that the oral LD50 value of G. serrata was estimated to be 5000 mg/kg. All extracts showed an effect on both stages of parasite development. The hatching inhibition rate was 100% from 3 mg/mL for all three extracts. The rate of inhibition of motility was 100% from 4 mg/mL for each extract. HEM is more efficient on eggs and Haemonchus contortus adult worms than other extracts with IC50 of 0.457 mg/mL and LC50 of 1.329 mg/mL, respectively. These results suggest that Gomphrena serrata, a plant used by farmers, has anthelmintic properties.

Sweetener and Flavor Enhancer Food Additives in Industrial Food Products Marketed in Dakar: Frequency and Diversity

Sweeteners and flavor enhancers are food additives widely used in industry, respectively, to add sweetness and flavor to foods. However, the presence of these substances is often criticized by consumers for their effects on health. What’s more, some scientific studies link these substances to certain pathologies. To guarantee food safety, competent authorities should have food standards based on risk analysis using consistent, reliable data. However, in developing countries, such data is often weak or non-existent. The aim of this study is therefore to carry out a pilot survey to establish the profile of sweeteners and flavour enhancers present in industrial food products marketed in Senegal. The methodology consisted of sampling various food products sold on the Senegalese market, based on analysis of labels containing information on ingredients, including additives. The investigation involved nine stores, one supermarket and 5 mini-markets in Dakar. The results showed the presence of 6 taste enhancers in food products, the most frequent being sodium L-monoglutamate (E621), inosinate (E631) and disodium guanylate (E627). Solid broths are the foodstuffs with the highest number of taste exhalters. As for sweeteners, 12 substances were identified, the most frequent being acesulfame potassium (E950), aspartame (E951), sucralose (E955) and saccharin (E954). Given the potential health risks associated with the consumption of these food additives, their control and monitoring on the market should be a priority for the competent authorities.

Contribution of Bone Scintigraphy in the Diagnosis of a Case of SAPHO in the Nuclear Medicine Department of Idrissa Pouye General Hospital (Dakar, Senegal)

Introduction: The acronym SAPHO (Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis) is a syndrome combining osteoarticular and cutaneous manifestations. It occurs mainly between the ages of 30 and 50. Sternocostoclavicular hyperostosis is one of the main distinguishing features. We report a case of SAPHO in Dakar diagnosed by bone scintigraphy. Observation: 28-year-old Senegalese women presented with left shoulder pain and relative functional impotence for over 2 years. Examination revealed right sternoclavicular hyperostosis and left shoulder pain on palpation. Questioning revealed a history of acne and hyperostosis of the right first toe. Bone scintigraphy, performed after injection of 630 MBq of 99mTc-HMDP, revealed: hyperfixation of the bilateral (right++) manubrio-sternal and sternoclavicular junction, producing the classic bull’s horn image;hyperfixation of the left shoulder with an inflammatory appearance;hyperfixation of the sacroiliac joints suggestive of bilateral sacroiliitis;hyperfixation of the right first toe;two mandibular hyper fixations probably related to dental damage. This scintigraphic appearance in one was strongly suggestive of SAPHO syndrome. Conclusion: SAPHO syndrome, related to spondyloarthropathy, associates cutaneous and osteoarticular signs. It is characterized by frequent delays in diagnosis due to poor recognition. Soy is an invaluable diagnostic tool, enabling us to assess the extent of the disease and its evolution.

Genetic Characterization of Nile Tilapia (Oreochromis niloticus) Strains from Senegal for Sustainable Local Aquaculture Production

The optimization of aquaculture production requires the selection of efficient strains. Thus, genetic improvement has become one of the important levers to boost the development of aquaculture. The objective of this study was to carry out genetic characterization of Nile tilapia Oreochromis niloticus, one of the most cultivated fish species in Senegal, in order to select an efficient strain to optimize local fish production. Thus, fish from five different populations (Richard-Toll, ANA, ITACA, Mbodiene and Sauvage) were analyzed, with 15 individuals per population. Genetic diversity and population structure were assessed using molecular genetic analyses by sequence characterized amplified region (SCAR) and microsatellite (SSR) markers. The analyses of the SCARII marker were conducted on four populations (ANA, ITACA, Sauvage and Mbodiene) while microsatellite analyses were conducted on all five populations. The results show high levels of polymorphism of SSR markers, and a high level of observed heterozygosity (Ho), indicating a high within-population genetic variability. These results are in agreement with the AMOVA results, which indicated a high within-population genetic variability (94%). The genetic structure analysis by DAPC indicates that the five populations analyzed are structured into four groups, which are highly heterogeneous because they share common allele individuals. The analysis of the genetic structure by AMOVA showed a low degree of differentiation between the populations (6%), in agreement with the genetic differentiation index (Fst = 0.059). The heterogeneity of studied populations implies a genetic flow over time, which may have existed between the original populations. The overall negative Tajima D values and low genetic differentiation indicate an excess of rare mutations in the populations studied, resulting from a recent population expansion from a limited number of initial breeders isolated in locale hatcheries. Thus, further studies with a much larger panel of markers are required to better differentiate the strains and identify the most efficient ones for sustainable local aquaculture production.

Identification of Natural and Artificial Colorants in Industrial Products Marketed in Senegal

Food colorants are widely used in the food industry to maintain or enhance product color. However, as the use of these colorants can have negative impacts on health, it is essential to analyze the risks associated with their consumption. This analysis requires, among other things, obtaining sufficient data on the presence of these colorants in foods, as well as their level of consumption. However, data on these colorants is often virtually non-existent in developing countries. The aim of this study was to determine the colorant profile of industrial products marketed in Senegal. Information on food additives was collected on 399 labels of different food product categories in shops located in Dakar. Data is recorded and processed using Excel software. Based on the Codex classification, analysis of the profile of additives identified on the labels of food samples revealed the presence of 31 colorants. The natural colorants identified are dominated by beta-carotene, widely present in beverages and dairy products, and paprika extract identified on cookies and industrial sauces. Artificial colors are dominated caramels present in several foods including bouillons, vinegars, sauces and hard candies. Secondly, there was a strong presence of the azo dye Sunset yellow FCF, widely found in samples of beverages, confectionery and cookies. The results of this case study enable us to appreciate the wide presence and diversity of colorants on the Senegalese market, and the importance of controlling them to guarantee consumer safety.

Profile of the Functional Categories of Food Additives in Industrial Foods Marketed in Senegal

Food additives, whether natural or artificial substances, are widely used around the world to improve the sensory quality of products, extend their shelf life and make them more competitive. However, the abusive and uncontrolled consumption of food additives is the cause of numerous illnesses and diseases such as poisoning, allergies, diabetes and numerous cancers. So, in addition to setting up control and regulatory bodies, it is becoming essential to keep a constant watch on the presence of food additives on the market. The aim of this study is to highlight the main categories of food additives in food products frequently sold on the Senegalese market. The methodology of the study is based on the identification of food additives from the information given on the labels of food packaging. Information was collected in markets in two (2) major regions of Senegal: Dakar and Saint-Louis. The results of our study show the presence of 153 food additives on the labels of 514 samples collected. Moreover, the frequency and diversity of additives depended on the food category. On the other hand, beyond their important technological and functional roles, some additives such as aspartame and monosodium glutamate have been implicated in pathologies, and others, such as titanium dioxide, are the subject of much controversy and even withdrawal in certain legislations for their impacts deemed potentially negative on consumer health.

Study of the Spatio-Temporal Variability of Rainfall in the Northern Region of Senegal

Senegal is a country of the Sahel. In this region, most of the populations live from agro-pastoral activities. The northern zone of Senegal is strongly influenced by river cultures. And the dynamics of the Senegal River are dependent on rainfall. The rainfall in the area is very closely linked to the dynamics of the atmosphere. The study of the spatio-temporal variability of rainfall in the northern region of Senegal requires quality rainfall observation data. It includes the Ferlo and the Senegal River valley, in particular the regions of Louga (department of Linguère included), Saint-Louis (departments of Dagana and Podor included) and Matam. These stations have been defined since Le Borgne (1988). The difficulty of having quality rain observation data can be resolved by using more accessible and good quality satellite data. Using satellite data, namely MSWEP, CRU, TAMSAT, ARC and PERSIANN, we showed the return of precipitation that appeared in 2000 and the unimodal cycle of precipitation in our study area. These data were validated using the correlation coefficient, the bias, the RMSE and the Nash index with observation data from the Regional Study Center for the Improvement of Adaptation to Drought (CERASS). The CRU data is then retained. Thus, this study made it possible to show the zonal distribution of rainfall in the northern zone of Senegal.

Anti-Biofilm, Anti-Quorum Sensing, and Anti-Proliferative Activities of Methanolic and Aqueous Roots Extracts of Carica papaya L. and Cocos nucifera L.

Objective: This study focused on the antibacterial and anti-proliferative activity of extracts from Carica papaya and Cocos nucifera roots. Methodology: The minimum inhibitory concentration and the minimum bactericidal concentration of the extracts on Escherichia coli, Pseudomonas aeruginosa, Streptococcus mutans, and Staphylococcus aureus were deduced by the microdilution method. The anti-biofilm activity was determined on all four strains and anti-quorum sensing activity by inhibition of violacein production in Chromobacterium violaceum. Anti-proliferative activity on prostate cultured cancer cells was evaluated by MTT assay. Sterols and triterpenes were also assayed in this study. Results: The methanolic extract of Carica papaya showed the best anti-biofilm effect with a percentage inhibition of 66.10 ± 1.79. The methanolic extract of Cocos nucifera had the strongest inhibition on the production of quorum sensing (61.42 ± 0.28). In addition, the methanolic extract of Cocos nucifera roots showed the best cytotoxic effect on prostate cancer LNCaP cell lines (IC50 = 26.98 ± 2.6 μg/mL) and Carica papaya on the PC-3 lines (IC50 = 127.20 ± 5.99 μg/mL). The extracts were also rich in triterpenes and sterols. Conclusion: This study provides support for the ethnomedical use of Carica papaya and Cocos nucifera roots as an antimicrobial and anticancer.

Analytical Modeling and Determination of the Characteristic Parameters of the Different Commercial Technologies of Photovoltaic Modules

This work presents a method of optimization of the photovoltaic generator (PV) based on the electrical model with a diode. The method consists of solving a second degree equation representing the derivative of the power function. The current and the maximum voltage being determined, the maximum power is deduced. Four popular types of photovoltaic panels from different manufacturers were considered for the study: BYD Model (BYD 320P6C-36), Atersa Grupo Model (A-320P GSE), SunPower Model (E19-320) and Model operated in the 50 MW power plant of Nouakchott-Mauritania (JKM320PP-72-V) of JinkoSolar. A comparative study is carried out between the simulated results and the data of the manufacturer of different technologies. The results obtained prove the effectiveness of the proposed method and that the BYD 320P6C-36 model is the most efficient among the four different technologies studied.

Trend Analysis in Rainfall, Reference Evapotranspiration and Aridity Index in Southern Senegal: Adaptation to the Vulnerability of Rainfed Rice Cultivation to Climate Change

Rainfall and evapotranspiration are two vital elements for food production under rainfed agriculture. This study aims at investigating the combined changes in these variables in the form of aridly index in the southern Senegal. The temporal trends in annual and monthly (from May to October) aridity index, rainfall and evapotranspiration are examined and adaptation strategies to the vulnerability of rainfed rice cultivation to the changes are developed. The results show a significant decreasing trend in annual rainfall at all study locations for the period 1922-2015. When analyzing the trends in sub-periods, there are two clear patterns in the annual rainfall series: a decreasing trend for the period 1922-1979 and a reversal increasing trend for the period 1980-2015. An increasing trend is also observed in annual reference evapotranspiration. The results reveal that the region will be drier with a significant increase in aridity at the annual and most monthly series. Appropriate adaptation strategies should be implemented to diminish the adverse influence of the increasing aridity on rice productivity for a sustainable agriculture.

Response of Soil Microbial Properties to Long-Term Application of Organic and Inorganic Amendments in a Tropical Soil (Saria, Burkina Faso)

Soil microbial biomass carbon (MBC), β-glucosidase, acid phosphatase and fluorescein diacetate (FDA) activities and bacterial community structure were assessed in a long-term (26 years) experiment, at physiological stages of sorghum growth, comparing different management methods for organic (manure, straw residues) and inorganic (urea) amendments at the INERA field station in Saria (Burkina Faso). Annual application of manure led to the highest soil microbial biomass and enzyme activities. Investigations indicated that only microbial biomass and β-glucosidase activities were affected during the cropping season. Phosphatase and FDA enzyme activities did not depend on the crop development stages. The application of N fertilizer modified phosphatase and FDA enzyme activities, the activities being higher in soils amended with N fertilizer. The bacterial community structure was analyzed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the eubacterial 16S rRNA gene. Cluster analysis of PCR-DGGE patterns showed two major clusters, the first containing the mineral fertilization and straw treatments and the second, the straw + urea, manure and manure + urea treatments. Sorghum grain yields were the highest for manure treatments. In this long-term experiment, applying straw did not produce a better grain yield than that obtained in the un-amended plot.

Study of HIV Prevalence and Behaviors in Rural Areas of Goudomp Health District (Senegal)

This study aims to determine the factors related to HIV-positive status in people aged 15 to 49 years of age in the commune of Niagha in Goudomp. The study was descriptive and analytically cross-cutting and had taken place in a release of 2018. The data was collected on anonymous questionnaires and then analyzed using R software after entering with Epi 7 software. Bivariate analyses and logistical modelling have been used to investigate the factors associated with HIV status. The sample included 400 people, and a participation rate of 100% was obtained in relation to the administration of the questionnaire. For the detection of HIV infection, 318 people agreed to do so, a proportion of 79.7%. The average age of the respondents was 27.8 years with a standard deviation of 9.1 and extremes of 15 to 49 years. 21.5% of respondents were under 20 years of age, the median was 26 years. With 58.8% of women, the sex ratio (M/F) was 0.7. In this study, 11.5% of respondents did not believe in the existence of HIV infection, 92.0% were sexually active, and 40.5% had sex with casual partners. The main places for casual sex were cultural events (84.0%), weekly markets (53.1%), religious events (27.8%) and during travel (22.8%). Among them, only 20 respondents, or 12.3%, declared that they systematically protect themselves with a condom during these occasional sexual relations. This wearing of condoms was found in 20.7% of singles and 10.7% of married couples having casual sex. In this study, 60.0% of the respondents declared that they had paid for sex, although this practice is not cited in income-generating activities. Non-consensual sex was found in 6.5% of the respondents. In this study, 319 people agreed to be tested for HIV, or 79.7% of the sample. HIV infection was found in 19 people, 6.0% seroprevalence, with 16 cases of HIV 1 infection and three cases of HIV 2 infection. Several risk behaviors were found in this study. However, none of them had a statistically significant link to HIV seropositivity. The prevalence of HIV infection in Niagha common is very high compared to data from the Sedhiou region and national level. Risky sexual behaviors are found in this population with no statistically significant link to HIV. Studies with a mixed approach would be more appropriate to study these relationships.

Suitable Temperature, Stocking Density and Feeding Rate for Optimal Growth of Sex Reversed Fry of Nile Tilapia Oreochromis niloticus (Senegal River Strain)

Determining the suitable fish farming conditions for optimal growth is necessary for aquaculture production, but it is not very obvious because it requires a good understanding of species biology. Thus, this study aims to evaluate the effects of different temperature regimes, stocking densities, and feeding rates on the growth of Nile tilapia, Oreochromis niloticus fingerlings that have been sex-reversed with 17α methyl testosterone. Three independent experiments were performed (with replicates) at the IRD Bel-Air fish farm (Dakar, Senegal) on 27-day-old fry maintained in six 25 L tanks with a batch of 100 individuals each. These fry were subjected to three different temperatures (26˚C, 28˚C, 30˚C;kept constant with thermostats), stocking densities (5, 10 and 15 ind/l) and feeding rates (5%, 10% and 15% of biomass;distributed three times a day). For the temperature and density treatments, fry was fed a pelleted feed containing 38% protein, distributed by hand at 10% of their total biomass, readjusted after each measurement. Growth performance (total weight, weight gain and daily weight gain), physicochemical parameters (temperature, oxygen, nitrite and phosphorus), feed conversion ratio (FCR) and survival rate (SR) were regularly monitored (weekly) during the experimental period. For the heat treatment, the results did not show an apparent relationship between growth performance and nitrite, phosphorus or dissolved oxygen (DO) contents. In contrast, there was a significant correlation between temperature and growth rates, with the best growth being obtained at 30˚C compared to 28˚C and 26˚C. Similarly, growth rates were correlated with stocking density and feeding rate but not with oxygen, temperature, nitrite or phosphorus levels. The best growth rates were observed at the lowest density (5 ind/l) and for the highest feeding rate (15% of biomass), which coincides with the best FCR and survival rates. Thus, 30˚C, 5 ind/l and 15% of biomass appeared to be the most favorable temperature, stocking density and feeding rate for optimal growth of Nile tilapia fry after inversion. The application of these results in the culture systems will allow to reach a good production of O. niloticus and thus to contribute to sustainable development of fish culture in Senegal.

Review of Research on Li-Ion Batteries Waste Management

Li-ion batteries (Libs) are a mature technology widely used for energy storage in various electronic devices. Nowadays, this technology has become a leading candidate for the portable electronics market and for electric vehicles due to its good performance. As a result, the demand for Libs containing critical metals, rare earth elements and precious metals is increasing day by day with the accelerated upgrades of consumer electronics, which promotes the supply risk of many mining resources. In addition, the problems associated with the production of end-of-life Lib are increasing on a global scale. Used Libs are e-waste containing significant levels of critical raw materials (such as Co, Li, Mn and Ni) along with harmful substances. Without proper management of Lib waste, these precious metals and toxic substances may end up in nature and cause environmental and public health problems. In order to preserve nature, ensure sustainable resource management and stimulate the circular economy, it has become crucial to properly manage and recycle end-of-life Li-ion batteries. By the way, conventional methods focusing on pyrometallurgical treatments combined with hydrometallurgical treatment are widely studied to recover design metals from Libs waste. It is in this context that we have conducted this bibliographic synthesis, focusing on the efficiency of the solvents employed and their competitiveness for a more environmentally friendly economic management. In this manuscript, recent leaching, solvent extraction, electrodeposition and precipitation strategies to recover precious metals from end-of-life Li-ion battery designs are reviewed and the evolution of these processes is discussed.

Spirulina Supplementation in Pregnant Women in the Dakar Region (Senegal)

The fight against iron deficiency anemia in pregnant women is a public health priority, especially in sub-Saharan Africa. Spirulina is an alga very rich in iron, used as a dietary supplement. This research proposes to study its effect on the hemogloblobinaemia of pregnant women. This was a blind randomized cohort study with a supplemented group of spirulina (1500 mg/d) and a second supplemented with iron and folic acid supplementation (IFAS). Included in this study were pregnant women attending four health centers in the Dakar region, with pregnancy at 28th amenorrhea, agreeing to participate and not having complications or twin pregnancies. Follow-up of the two groups was identical throughout the study from the 28th week of amenorrhea to the 42nd postnatal day. The study was conducted among 920 women, evenly distributed among the groups. IFAS allowed a statistically significant increase in hemoglobinemia with an average gain of 0.3 g/dl between the 28th and 32nd weeks of amenorrhea (p = 0.022) and 0.2 g/dl between the 28th week and the delivery (p = 0.043). Spirulina supplementation showed statistically higher gains than those observed with IFAS. These gains were 0.48 g/dl between the 28th and 32nd weeks of amenorrhea and 0.36 g/dl between the 28th week and the delivery, with p values less than 0.001. Spirulina, more accessible to developing countries, is a good option to strengthen the arsenal of iron deficiency anemia control, and therefore maternal mortality.