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Illegal tin mining or unconventional mining activities produce tailings. Tailings contain dangerous heavy metals one of which is Lead (Pb). The increasing concentration of Pb in the waters will also increase its concentration in the body of the biota, one of which is shrimp. The purpose of this study was to analyse the Pb content in gills, hepatopancreas and muscle in Penaeus merguiensis, analyse the Pb content in water and sediments, measure the ability of Penaeus merguiensis in accumulating Pb in water and sediments, and determine the safe limit for consumption. Shrimp, water and sediment samples were analysed using AAS. The results showed that the highest Pb concentration in Penaeus merguiensis was hepatopancreas> gill> meat, with an average range of 0,1897–0,4064 mg/kg, gills 0,2424-0,4770 mg/kg, and meat 0,1348-0,1636 mg/kg. The average Pb concentration in water ranged from 0,2624 to 0,5713 mg/L, while the sediment ranged from 0,2783 to 0,9760 mg/kg. The ability of Penaeus merguensis to accumulate Pb included in the low category. The value of daily intake is around 9,760-11,128 kg/week. Aktivitas penambangan timah illegal atau tambang inkonvensional menghasilkan sisa limbah buangan (Tailing). Tailing mengandung logam berat berbahaya salah satunya Timbal (Pb). Meningkatnya konsentrasi Pb di perairan akan meningkat pula konsentrasinya dalam tubuh biota, salah satunya udang. Tujuan dilakukannya penelitian ini adalah menganalisis kandungan Pb pada insang, hepatopankreas dan daging pada Penaeus merguiensis, menganalisis kandungan Pb pada air dan sedimen, mengukur kemampuan Penaeus merguiensis dalam mengakumulasikan Pb di air dan sedimen, dan menentukan nilai batas aman konsumsi. Sampel udang, air dan sedimen dianalisis menggunakan AAS. Hasil penelitian menunjukkan bahwa konsentrasi Pb tertinggi pada Penaeus merguiensis adalah hepatopankreas>insang>daging, dengan kisaran rata-rata 0,1897–0,4064 mg/kg, insang 0,2424-0,4770 mg/kg, dan daging 0,1348-0,1636 mg/kg. Konsentrasi Pb rata-rata dalam air berkisar antara 0,2624-0,5713 mg/L, sementara sedimen berkisar dari 0,2783-0,9760 mg/kg. Kemampuan Penaeus merguensis untuk mengakumulasi Pb termasuk dalam kategori rendah. Nilai asupan harian sekitar 9,760-11,128 kg/minggu.

Artykuł przedstawia krótką refleksję na temat płciowego wymiaru przestrzeni w odpowiedzi na rozważania Witolda Wachowskiego w książce Poznanie rozproszone. Od heurystyk do mechanizmów (2022). Autorka umieszcza pracę Wachowskiego w nurcie tak zwanego „zwrotu ku przestrzeni”, zgodnie z którym otoczenie traktujemy jako integralną część kultury, a kulturę zaś jako proces poznawczy. Prezentuje zaczerpnięte z literatury przedmiotu wybrane przykłady ilustrujące, jak szeroko rozumiana przestrzeń może kształtować i utrwalać stereotypy płciowe. Jej celem jest zainspirowanie do prowadzenia dalszych, pogłębionych badań na temat relacji między płcią a przestrzenią w kontekście teorii rozproszonego poznania czy szerzej – badań nad poznaniem i procesami poznawczymi w ogóle. ----------------------------------------- Zgłoszono: 02/01/2024. Zrecenzowano: 30/01/2024. Zaakceptowano do publikacji: 24/04/2024.

Due to its unique properties tungsten is a promising candidate as plasma-facing-material (PFM) in future nuclear fusion reactors. Tungsten features an exceptionally high melting point, high thermal conductivity, low tritium inventory and comparatively low erosion rate under plasma loading [1]. But given the extreme loads on the PFM during operation of a fusion reactor, the lifetime of plasma-facing components (PFC)s is limited. Currently, it is planned to replace damaged PFCs when they reach the end of their service life. However, the lifetime of PFCs could be increased by in situ repair using additive manufacturing technology (AM) in the form of direct-energy-deposition (DED). The wire–based laser metal deposition process (LMD-w) meets several necessary conditions for operation in the vessel and could be used for performing such in situ repairs.It was investigated if the LMD-w process is able to heal thermal induced surface cracks and roughening by remelting the substrate during deposition of tungsten. For this purpose, tungsten samples of 12 × 12 × 5 mm3, which later served as substrate plates for the LMD-w experiments, were treated with combined steady-state and transient thermal loads in the electron beam facility JUDITH 2. These samples were brazed to a copper cooling structure and exposed to 105 thermal shocks of 0.5 ms duration and an intensity of Labs = 0.55 GW m−2 (FHF = 12 MW s0.5 m−2) at a base temperature of Tbase = 700 °C. This way, edge localized mode (ELM) like thermal load damage was induced on the tungsten samples. On these samples, different LMD-w and laser remelting process strategies were performed. Subsequently, these samples were analyzed, and it was examined that the healing of the pre-damaged substrate material was successful. In parallel, the laser remelting process was modeled in a thermal transient finite element method (FEM) simulation in order to gain an insight into the temperatures prevailing in the material during the process.

Plasma-facing components (PFC) in nuclear fusion reactors are exposed to demanding conditions during operation. The combination of thermal loads, plasma exposure as well as neutron induced damage and activation limits the number of materials suitable for this application. Due to its properties, tungsten (W) is foreseen as plasma-facing material (PFM) for the future DEMOnstration power plant. It is considered suitable due to its exceptionally high melting point, excellent thermal conductivity, low tritium retention and low erosion resistance during plasma exposure. But even tungsten armored PFCs have a limited lifetime due to, among other factors, surface erosion and the resulting thickness reduction of the armor material.In-situ local deposition of tungsten by means of additive manufacturing (AM) could counteract surface erosion and thus increase the service life span of PFCs. After evaluation of the potential AM processes qualified for this task, the wire-based laser metal deposition (LMD-w) process was selected as the most suitable process. First trials were conducted to examine if it is possible to reliably deposit tungsten onto tungsten substrate using the LMD-w process. In these first studies, single welding beads were generated, and in later experiments, entire layers were created from several welding beads which are arranged next to each other. To ensure reproducibility of the results, the substrate temperature was kept constant. Further experiments aimed at the elimination or minimization of problems such as oxidation, occurrence of balling defects, porosity, cracking, surface waviness and insufficient connection to the substrate. To increase the welding bead quality, the input parameters like laser power, deposition velocity, wire feed rate, inert gas flow, as well as the wire position were optimized. Furthermore, stacking of several layers, as well as the remelting of an already created layer, were carried out and investigated. This study represents the first steps in testing the feasibility of an in-situ surface regeneration concept for PFCs.

Abstract Background Malaria infection during pregnancy (MIP) is not only deleterious to the woman, but it also puts her fetus at increased risk of adverse outcomes, such as preterm delivery, low birth weight, and intrauterine growth retardation. Additionally, all-cause mortality during the first year of life in babies born to women with malaria during pregnancy is also increased. Many interventions such as IPTp-SP and long-lasting insecticidal nets have proven to be efficient at reducing malaria in pregnancy burden but adherence to recommended policies remains poor. In sub-Saharan Africa, malaria in pregnancy is often asymptomatic and many malaria infections may be missed due to the inadequate performance of the current rapid diagnostic test to detect low-level parasitemias. Therefore, additional strategies such as intermittent screening with ultrasensitive rapid diagnostic tests and treatment with an effective artemisinin-based combination therapy in addition to IPTp-SP could reduce placental malaria, peripheral malaria infection at delivery, and low birth weight. Methods This pilot 2-group randomized open trial with a nested qualitative social behavioral will be carried out in Nanoro district in which 340 pregnant women will be recruited. Pregnant women will be randomized into two groups and followed on a monthly basis until delivery. In the intervention group, monthly screening using ultrasensitive rapid diagnostic tests and treatment of those found to be infected with dihydroartemisinin-piperaquine will be performed. In addition, a reminder will be sent to increase the uptake of IPTp-SP doses per woman. During scheduled and unscheduled visits, malaria infection, hemoglobin level, and other clinical outcomes will be assessed and compared by the group. The primary feasibility outcome will evaluate the study site's capacity to enroll participants and the women’s perception and acceptability of the intervention. The primary clinical outcome will be the prevalence of placental malaria at delivery. Discussion The present protocol aims to evaluate the feasibility on a large-scale and also to demonstrate the impact and the operational feasibility of additional screening with ultrasensitive rapid diagnostic tests and treatment with DHA-PQ on placental malaria, low birth weight, and peripheral malaria infection at delivery in a high-burden setting in Burkina Faso. Trial registration ClinicalTrials.gov , ID: NCT04147546 (14 October 2019).

The synthesis of biomimetic thioesters for enzymatic studies of ketoreductase (KR) domains from polyketide synthases is described. A TBS-protected dihydroxyalkene fragment was synthesised by a sequence involving a Nagao acetate aldol reaction, a Mukaiyama propionate aldol reaction, and a methylene Wittig olefination. Fragment coupling to N -acetylcysteamine (SNAC) (E)-3-hydroxyhex-4-enethioates by an olefin cross-metathesis (OCM) and subsequent deprotection gave the potential KR product stereoisomers. An analogous OCM with a SNAC (E)-3-ketohex-4-enethioate did not give the desired KR precursor, but the reaction could successfully be replaced by a Horner–Wadsworth–Emmons olefination between a SNAC 3-ketothioester phosphonate and a TBS-protected dihydroxy aldehyde. After deprotection, an intramolecular cyclisation was observed that needs to be considered as a spontaneous side reactivity in the enzymatic assays. [ABSTRACT FROM AUTHOR]

Abstract Background Plasmodium falciparum malaria remains a major public health concern in sub-Sahara Africa. Seasonal malaria chemoprevention (SMC) with amodiaquine + sulfadoxine-pyrimethamine is one of the most important preventive interventions. Despite its implementation, the burden of malaria is still very high in children under five years old in Burkina Faso, suggesting that the expected impact of this promising strategy might not be attained. Development of innovative strategies to improve the efficacy of these existing malaria control measures is essential. In such context, we postulate that screening and treatment of malaria in household members of children receiving SMC could greatly improve the impact of SMC intervention and reduce malaria transmission in endemic settings. Methods This randomized superiority trial will be carried out in the Nanoro health district, Burkina Faso. The unit of randomisation will be the household and all eligible children from a household will be allocated to the same study group. Households with 3–59 months old children will be assigned to either (i) control group (SMC alone) or (ii) intervention (SMC+ screening of household members with standard Histidin Rich Protein Rapid Diagnostic Test (HRP2-RDT) and treatment if positive). The sample size will be 526 isolated households per arm, i.e., around 1052 children under SMC coverage and an expected 1315 household members. Included children will be followed-up for 24 months to fully cover two consecutive malaria transmission seasons and two SMC cycles. Children will be actively followed-up during the malaria transmission seasons while in the dry seasons the follow-up will be passive. Conclusion The study will respond to a major public health concern by providing evidence of the efficacy of an innovative strategy to boost the impact of SMC intervention.

Abstract Background Investigating malaria transmission dynamics is essential to inform policy decision making. Whether multiplicity of infection (MOI) dynamic from individual infections could be a reliable malaria metric in high transmission settings with marked variation in seasons of malaria transmission has been poorly assessed. This study aimed at investigating factors driving Plasmodium falciparum MOI and genetic diversity in a hyperendemic area of Burkina Faso. Methods Blood samples collected from a pharmacovigilance trial were used for polymerase chain reaction genotyping of the merozoite surface proteins 1 and 2. MOI was defined as the number of distinct parasite genotypes co-existing within a particular infection. Monthly rainfall data were obtained from satellite data of the Global Precipitation Measurement Database while monthly malaria incidence aggregated data were extracted from District Health Information Software 2 medical data of the Center-West health regional direction. Results In the study area, infected people harboured an average of 2.732 (± 0.056) different parasite genotypes. A significant correlation between the monthly MOI and the monthly malaria incidence was observed, suggesting that MOI could be a good predictor of transmission intensity. A strong effect of season on MOI was observed, with infected patients harbouring higher number of parasite genotypes during the rainy season as compared to the dry season. There was a negative relationship between MOI and host age. In addition, MOI decreased with increasing parasite densities, suggesting that there was a within-host competition among co-infecting genetically distinct P. falciparum variants. Each allelic family of the msp1 and msp2 genes was present all year round with no significant monthly fluctuation. Conclusions In high malaria endemic settings with marked variation in seasons of malaria transmission, MOI represents an appropriate malaria metric which provides useful information about the longitudinal changes in malaria transmission in a given area. Besides transmission season, patient age and parasite density are important factors to consider for better understanding of variations in MOI. All allelic families of msp1 and msp2 genes were found in both dry and rainy season. The approach offers the opportunity of translating genotyping data into relevant epidemiological information for malaria control.

Toussaint Rouamba,1,2 Paul Sondo,1 Karim Derra,1 Seydou Nakanabo-Diallo,1,3 Biebo Bihoun,1 Eli Rouamba,1 Zekiba Tarnagda,1 Adama Kazienga,1 Innocent Valea,1 Hermann Sorgho,1 Franco Pagnoni,4 Fati Samadoulougou-Kirakoya,2 Halidou Tinto1 1Clinical Research Unit of Nanoro, Institut de Recherche en Sciences de la Santé, Centre National de la Recherche Scientifique et Technologique, Ouagadougou, Burkina Faso; 2Center for Research in Epidemiology, Biostatistics and Clinical Research, School of Public Health, Université Libre de Bruxelles (ULB), Bruxelles, Belgium; 3Department of Clinical Research, Centre Muraz, Bobo-Dioulasso, Burkina Faso; 4World Health Organization, Geneva, SwitzerlandCorrespondence: Toussaint RouambaClinical Research Unit of Nanoro, Institut de Recherche en Sciences de la Santé, Centre National de la Recherche Scientifique et Technologique, 42, Avenue Kumda-Yonre, 11 BP 218 Ouaga CMS 11, Ouagadougou, Burkina FasoTel +226 6665 3204Email rouambatoussaint@gmail.comBackground and purpose: Resource-limited countries face challenges in setting up effective pharmacovigilance systems. This study aimed to monitor the occurrence of adverse events (AEs) after the use of artemisinin-based combination therapies (ACTs), identify potential drivers of reporting suspected adverse drug reactions (ADRs) and monitor AEs among women who were inadvertently exposed to ACTs in the first trimester of pregnancy.Patients and methods: We conducted a prospective observational study from May 2010 to July 2012 in Nanoro Health and Demographic Surveillance System (HDSS), Burkina Faso. The HDSS area was divided into active and passive surveillance areas to monitor AEs among patients (regardless of age or sex) who received a first-line ACT (artemether–lumefantrine or artesunate–amodiaquine). In the active surveillance area, patients were followed up for 28 days, while in the passive surveillance area, patients were encouraged to return voluntarily to the health facility to report any occurrence of AEs until day 28 after drug intake. We assessed the crude incidence rates of AEs in both cohorts and performed Cox regression with mixed random effects to identify potential drivers of ADR occurrence.Results: In total, 3170 participants were included in the study. Of these, 40.3% had reported at least one AE, with 39.6% and 44.4% from active and passive surveillance groups, respectively. The types of ADRs were similar in both groups. The most frequent reported ADRs were anorexia, weakness, cough, dizziness and pruritus. One case of abortion and eight cases of death were reported, but none of them was related to the ACT. The variance in random factors showed a high variability of ADR occurrence between patients in both groups, whereas variability between health facilities was low in the active surveillance group and high in passive surveillance group. Taking more than two concomitant medications was associated with high hazard in ADR occurrence, whereas the rainy season was associated with low hazard.Conclusion: This study showed that both passive and active surveillance approaches were useful tools. The HDSS allowed us to capture a few cases of exposure during the first trimester of pregnancy. The passive surveillance approach, which is more likely to be implemented by malaria control programs, seems to be more relevant in the Sub-Saharan African context.Keywords: HDSS, artemisinin-based combination therapies, safety, pregnancy, malaria, rural, Burkina Faso