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Bioinspired supramolecular macrocycle hybrid membranes with enhanced proton conductivity

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Nano Research 2024年第2期17卷 797-805页

作者： Pengfei Yang Linlin Xu Panagiotis Trogadas Marc-olivier Coppens Yang Lan Centre for Nature Inspired Engineering Department of Chemical EngineeringUniversity College LondonLondon WC1E 7JEUK

Enhancing the proton conductivity of proton exchange membranes(PEMs)is essential to expand the applications of proton exchange membrane fuel cells(PEMFCs).Inspired by the proton conduction mechanism of bacteriorhodopsin,cucurbit[n]urils(CB[n],where n is the number of glycoluril units,n=6,7,or 8)are introduced into sulfonated poly(ether ether ketone)(SPEEK)matrix to fabricate hybrid PEMs,employing a nature-inspired chemical engineering(NICE)methodology.The carbonyl groups of CB[n]act as proton-conducting sites,while the host–guest interaction between CB[n]and water molecules offers extra protonconducting pathways.Additionally,the molecular size of CB[n]aids in their dispersion within the SPEEK matrix,effectively bridging the unconnected proton-conducting sulfonic group domains within the SPEEK membrane.Consequently,all hybrid membranes exhibit significantly enhanced proton conductivity.Notably,the SPEEK membrane incorporating 1 wt.%CB[8](CB[8]/SPEEK-1%)demonstrates the highest proton conductivity of 198.0 mS·cm^(−1) at 60°C and 100%relative humidity(RH),which is 228%greater than that of the pure SPEEK membrane under the same conditions.Moreover,hybrid membranes exhibit superior fuel cell performance.The CB[8]/SPEEK-1%membrane achieves a maximum power density of 214 mW·cm^(−2),representing a 140%improvement over the pure SPEEK membrane(89 mW·cm^(−2))at 50°C and 100%RH.These findings serve as a foundation for constructing continuous proton-conducting pathways within membranes by utilizing supramolecular macrocycles as fuel cell electrolytes and in other applications.

关键词： supramolecular macrocycle proton conductivity cucurbit[n]uril proton exchange membrane fuel cell

印度Haritalyangar地区晚中新世猪类化石新材料

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古脊椎动物学报（中英文） 2024年第1期62卷 69-84页

作者： Anek R.SANKHYAN olivier CHAVASSEAU 古生物研究会古马尔温174021印度喜马偕尔邦法国普瓦蒂埃大学法国国家科学研究中心UMR 7262普瓦蒂埃市86073

描述了印度北部比拉斯布尔区喜马偕尔邦Haritalyangar地区中西瓦利克的猪类化石上、下颌及牙齿材料。Haritalyangar地区以晚中新世动物群、古人类和其他灵长类动物的多样性而闻名。研究材料为作者之一(ARS)在该地区多次野外季采集的猪... 详细信息

描述了印度北部比拉斯布尔区喜马偕尔邦Haritalyangar地区中西瓦利克的猪类化石上、下颌及牙齿材料。Haritalyangar地区以晚中新世动物群、古人类和其他灵长类动物的多样性而闻名。研究材料为作者之一(ARS)在该地区多次野外季采集的猪类化石;猪类化石地点和最近报道的长鼻类化石地点(含古猿化石地点)均被绘制在地图上。这些化石地点广泛分布于Makkan Khad到Sir Khad区域内的“Lower Alternations”层和“Upper Alternations”层。猪类化石被鉴定为3个属:原河猪属Propotamochoerus(P.hysudricus)、河马齿河猪属Hippopotamodon(H.sivalense)和云南猪属Yunnanochoerus(Y.dangari)。Propotamochoerus hysudricus为中西瓦利克最常见的化石猪类,新发现的Yunnanochoerus dangari进一步证明这种古猪类化石仅在Haritalyangar地区有少量遗存。Haritalyangar地区新发现的猪类化石组成与巴基斯坦的Nagri动物群相近。基于猪类化石进行的Potwar高原年代地层学对比表明,Haritalyangar地区的“Lower Alternations”层的年龄范围为~10–9 Ma,与最新的磁极性地层学年代范围很接近。

关键词：中西瓦利克晚中新世猪超科云南猪属原河猪属河马齿河猪属

Watson-Jones Anatomical Approach for Open Reduction and Internal Fixation of Proximal Femoral Fractures without Image Intensifier in a Low-Resource Setting

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Open Journal of Orthopedics 2024年第4期14卷 173-186页

作者： Loïc Fonkoue Gaspary Fodjeu Kennedy olivier Muluem olivier Ngongang Theophile Nana Marie Ange Ngo Yamben DésiréAkaba Urich Tambekou Daniel Eone Handy Department of Orthopaedics and Trauma Yaound&#233 General Hospital Yaound&#233 Cameroon. Department of Surgery and Specialities University of Yaound&#233 1 Yaound&#233 Cameroon Department of Orthopaedics and Trauma Yaound&#233 Emergency Center Yaound&#233 Cameroon Department of Orthopaedics and Trauma Yaound&#233 Central Hospital Yaound&#233 Cameroon

Introduction: Standard procedures for surgical fixation of proximal femoral fractures (PFF) require an image intensifier which in developing countries remains a luxury. We hypothesized that, with a well-codified technique, the Watson Jones approach (WJA) without image intensifier nor traction table, can allow open reduction and internal fixation (ORIF) of PFF using Dynamic hip screw (DHS), with satisfactory outcome. Patients and methods: Forty one consecutive patients (mean age 59.5 ± 21.6 years, 61% males) who were followed in a Teaching Hospital for PFF treated by ORIF using the WJA and DHS from January 2016 to December 2020 were reassessed. The outcome measures were the quality of the reduction, the positioning of the implants, the tip-apex distance (TAD), the rate and delay of consolidation, the functional results using Postel Merle d’Aubigné (PMA) score, the rate of surgical site infection (SSI) and the overall mortality. Logistic regression was used to determine factors associated with mechanical failure. Results: The mean follow-up period was 33.8 ± 15.0 months. Fracture reduction was good in 31 (75.6%) cases and acceptable in 8(19.5%) cases. Implant position was fair to good in 37 (90.2%) patients. The mean TAD was 26.1 ± 3.9 mm. Three patients developed SSI. Consolidation was achieved in 38 (92.6%) patients. The functional results were good to excellent in 80.5% of patients. The overall mortality rate was 7.3%. There were an association between mechanical failure and osteoporosis (p = 0.04), fracture reduction (p = 0.003), and TAD (p = 0.025). In multivariate logistic regression, no independent factors were predictive of mechanical failure. Conclusion: This study shows that ORIF using DHS for PFF via the Watson-Jones approach without an image intensifier can give satisfactory anatomical and functional outcomes in low-resource settings. It provides and validates a reliable and reproducible technique that deserves to be diffused to surgeons in austere areas over the world.

关键词： Proximal Femoral Fracture Watson-Jones Approach Dynamic Hip Screw Low Resource Setting

Evaluation of Procedural Pain in Neonates in Cameroon

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Open Journal of Pediatrics 2024年第3期14卷 568-578页

作者： Claude-Audrey Meguieze Rose Bidias Etouckey Georges Eric Nseme Koki Ndombo Paul olivier Pediatrics Department Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroon Morphologic Sciences Department Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroon

Introduction: Acute pain associated with caregiving is a major cause of pain among neonates. Left untreated, it can lead to long-term neurosensory and psychoaffective consequences. In Cameroon, this subject has been scarcely explored, thus constituting an impediment to the management of care-induced pain. Objective: Assess procedural pain in neonates in Yaoundé. Material and Methods: We conducted a cross sectional study with prospective data collection over a period of eight months (October 2022 to May 2023) in three hospitals. We included neonates who were being cared for and were not crying prior to the onset of healthcare, whose parents consented to the study. Assessments were done using the DAN scale, which is specific to care-induced pain. Data was entered and analyzed using SPSS 23.0 software. Results: A total of 161 newborns were included. The hospital prevalence of care-induced pain in neonates was 85%. Neonatal sepsis was the main cause for admission (96.6%). The most common procedures were venous blood sampling (94.4%) and insertion of peripheral venous lines (93.8%). The pain intensity for these procedures was severe (83.9%). The most painful procedure was lumbar tap, followed by venous access procedures. Conclusion: Neonates in hospitals are subjected to many painful procedures. The pain experienced during these procedures is severe. The most nociceptive procedure is a lumbar puncture.

关键词： Assessment Procedural Pain Neonate Yaoundé Cameroon

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 574-586页

作者： olivier Kerdiles Méryl-Farelle Oye Mintsa Mi-mba Katherine Coulombe Cyntia Tremblay VincentÉmond Martine Saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon Facultéde pharmacie UniversitéLaval1050 Avenue de la MédecineQuebecQCCanada Axe Neuroscience Centre de recherche du CHU de Québec-UniversitéLaval(Pavillon CHUL)2705 Boulevard LaurierQuebecQCCanada Institute of Nutrition and Functional Foods QuebecQCCanada Optinutribrain International Associated Laboratory(NutriNeuro FranceINAFCanada)QuebecQCCanada Axe Endocrinologie et Néphrologie Centre de recherche du CHU de Québec-UniversitéLavalQuebecQCCanada Département de Médecine Facultéde MédecineUniversitéLavalQuebecQCCanada Département de Psychiatrie et Neurosciences Facultéde MédecineQuebecQCCanada

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after diagnosis.Given that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic pathway.First,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal denervation.Four weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 weeks.During this period,the animals had access to a running wheel,which they could use or not.Docosahexaenoic acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars compacta.However,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned striatum.Compared to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned striatum.The present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

关键词： 6-hydroxydopamine dopamine dopamine transporter exercise neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3

Actors of Psychoactive Drug Initiation among Adolescents in Yaoundé-Cameroon

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Open Journal of Pediatrics 2024年第2期14卷 246-254页

作者： Claude-Audrey Meguieze Atabe Ngwene Neri Ngole Georges Eric Nseme Etouckey Paul olivier Koki Ndombo Department of Pediatrics Faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon Department of Morphologic Sciences Faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaoundé Cameroon

Introduction: Actors of psychoactive drug initiation refer to those who introduce others to psychoactive drug use (initiators) and those who are introduced to psychoactive drugs (users). By identifying their features, better prevention and intervention programs can be developed to reduce psychoactive drug use among adolescents. This article describes the role of actors of psychoactive drug initiation among teenagers in secondary schools in Yaoundé (Cameroon). Methodology: A cross sectional study was carried out in twelve secondary schools in Yaoundé from October 2022 to May 2023. Adolescents from Form four to upper sixth, who assented to participate in the study and received parental consent were included. Data were collected in a structured self-reported questionnaire and analyzed using SPSS 23. Quantitative variables were expressed using means, standard deviations, median and interquartile ranges depending on the distribution of data. Qualitative variables were expressed in the form of frequency and percentages. Results: Drug use was more prevalent among male adolescents (55.3%) from nuclear families (91.4%) who received relatively high pocket money. The main sources of drug exposure were non-family members (49.7%), especially friends outside school. The most frequent place of initiation was snack bars (33.1%). Conclusion: The study revealed the importance of the family, friends and leisure places in the initiation process of drug use in teenagers. Based on these results, parents and school authorities should work together to create a safe and supportive environment that fosters communication, education to prevent drug abuse among adolescents in Yaoundé.

关键词： Initiators Drug Users Adolescents Cameroon

Application of near-infrared spectroscopy for fast germplasm analysis and classification in multi-environment using intact-seed peanut(Arachis hypogaea L.)

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Oil Crop Science 2024年第2期9卷 132-141页

作者： Fentanesh Chekole Kassie Gilles Chaix Hermine Bille Ngalle Maguette Seye Coura Fall Hodo-Abalo Tossim Aissatou Sambou olivier Gibert Fabrice Davrieux Joseph Martin Bell Jean-Francois Rami Daniel Fonceka Joel Romaric Nguepjop Department of Plant Biology and Physiology Faculty of SciencesUniversity of Yaounde IYaoundeP.O.Box 337Cameroon Department of Plant Science College of AgricultureWolaita Sodo UniversitySodoP.O.Box 138Ethiopia CIRAD UMR AGAP InstitutMontpellierFrance AGAP Institut Univ MontpellierCIRADINRAEInstitut AgroMontpellierFrance ChemHouse Research Group MontpellierFrance Centre D’Etudes Regional Pour L’Amelioration de L’Adaptation a La Secheresse(CERAAS/ISRA) Route de KhomboleThiesBP 3320Senegal Dispositif de Recherche et de Formation en Partenariat Innovation et Amelioration Varietale en Afrique de L’Ouest(IAVAO)CERAASRoute de KhomboleThiesBP 3320Senegal CIRAD UMR QUALISUDSaint PierreFrance

Peanut is a worldwide oilseed crop and the need to assess germplasm in a non-destructive manner is important for seed nutritional breeding.In this study,Near Infrared Spectroscopy(NIRS)was applied to rapidly assess germplasm variability from whole seed of 699 samples,field-collected and assembled in four genetic and environmentbased sets:one set of 300 varieties of a core-collection and three sets of 133 genotypes of an interspecific population,evaluated in three environments in a large spatial scale of two countries,Mbalmayo and Bafia in Cameroon and Nioro in Senegal,under rainfed conditions.NIR elemental spectra were gathered on six subsets of seeds of each sample,after three rotation scans,with a spectral resolution of 16 cm-1over the spectral range of867 nm to 2530 nm.Spectra were then processed by principal component analysis(PCA)coupled with Partial least squares-discriminant analysis(PLS-DA).As results,a huge variability was found between varieties and genotypes for all NIR wavelength within and between environments.The magnitude of genetic variation was particularly observed at 11 relevant wavelengths such as 1723 nm,usually related to oil content and fatty acid composition.PCA yielded the most chemical attributes in three significant PCs(i.e.,eigenvalues>10),which together captured 93%of the total variation,revealing genetic and environment structure of varieties and genotypes into four clusters,corresponding to the four samples sets.The pattern of genetic variability of the interspecific population covers,remarkably half of spectrum of the core-collection,turning out to be the largest.Interestingly,a PLS-DA model was developed and a strong accuracy of 99.6%was achieved for the four sets,aiming to classify each seed sample according to environment origin.The confusion matrix achieved for the two sets of Bafia and Nioro showed 100%of instances classified correctly with 100%at both sensitivity and specificity,confirming that their seed quality was different from each other and all other samples.Overall,NIR

关键词： Groundnut Oilseed Near infrared spectroscopy Germplasm analysis Environment Nutritional Breeding

Comparative Study of the Physicochemical Quality of the Waters of the Méné River (Sassandra Watershed, Ivory Coast) in the Dry Season and in the Rainy Season

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Journal of Environmental Protection 2024年第6期15卷 738-746页

作者： Konan Lopez Kouamé Gansso Valentin Akilinon olivier Simon Mananga Kombo Gneneyougo Emile Soro Bi Tié Albert Goula Science and Technology Department Alassane Ouattara University Bouak Ivory Coast Environmental Sciences Laboratory Nangui Abrogoua University Abidjan Ivory Coast

The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from the river during a period of dry season (January-February) and a period of rainy season (June and September). The various physicochemical parameters were measured according to Afnor standardized methods. The readings of temperature, turbidity, pH and conductivity made it possible to account for the disturbances occurring in water quality. A temporal variation correlated with the seasons (dry or rainy) is noted. Turbidity depends on the concentration of suspended solids (SS) in the water and drained particles and therefore on the seasons. Just like the temperature, the conductivity changes with the season. The waters of the Méné River are generally acidic. The results obtained show that there is a low level of pollution by chlorides, phosphates, nitrites and nitrates. A slight pollution of the waters of Méné in organic matter (chemical oxygen demand values are less than 25 mg∙L−1 during dry season and 32.33 ± 4.73 mg∙L−1 during rainy season) was observed. The concentrations of metallic trace elements such as iron, manganese and aluminum indicate significant pollution of these waters by these elements. Overall, the waters of the Méné River are of satisfactory quality because all the physicochemical parameters analyzed have values below standards during the dry season as well as during the rainy season with the exception of COD and a few metallic trace elements.

关键词： Méné Physicochemical Parameters River Season Water Quality

Optimization of Biofuel Formulation by Mixture Design

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Advances in Chemical Engineering and Science 2024年第1期14卷 48-56页

作者： Konan Edmond Kouassi Abollé Abollé Kouamé olivier-Marc Kouakou David Boa N’guessan Raymond Kré Kouassi Benjamin Yao Laboratory of Thermodynamics and Physical Chemistry of the Environment (LTPCM) UFR-SFA University of Nangui ABROGOUA Abidjan C&#244te d’Ivoire Laboratory of Fundamental and Applied Physics (LPFA) UFR-SFA University of Nangui ABROGOUA Abidjan C&#244te d’Ivoire Laboratory of Industrial Processes for the Synthesis of the Environment and New Energies (LAPISEN) of the Félix Houphouë t Boigny National Polytechnic Institute Yamoussoukro C&#244te d’Ivoire

With the full growth of energy needs in the world, several studies are now focused on finding renewable sources. The aim of this work is to optimise biofuel formulation from a mixture design by studying physical properties, such as specific gravity and kinematic viscosity of various formulated mixtures. Optimization from the mixture plan revealed that in the chosen experimental domain, the optimal conditions are: 40% for used frying oil (UFO), 50% for bioethanol and 10% for diesel. These experimental conditions lead to a biofuel with a density of 0.84 and a kinematic viscosity of 2.97 cSt. These parameters are compliant with the diesel quality certificate in tropical areas. These density and viscosity values were determined according to respective desirability values of 0.68 and 0.75.

关键词： Biofuel Optimization Mixture Design