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Length-Weight Relationships and Condition Factors of 15 Fish Species from the Loémé River Basin (Mayombe, Republic of Congo)

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Open Journal of Ecology 2023年第12期13卷 883-893页

作者： Honest Freedom Poaty Ngot Victor Mamonekene Armel Ibala Zamba Leendert Van den Berg César Ngoulou dabney Matoko Kouediatouka Aulne Lérège Batiabo Mikembi Hélène dembe Louvinguila Tenda Institut National de Recherche en Sciences Exactes et Naturelles IRSEN Brazzaville République du Congo Faculté de Sciences et Techniques (FST) Université Marien Ngouabi Brazzaville République du Congo Ecole Nationale Supérieure Agronomie et de Foresterie (ENSAF) Université Marien Ngouabi Brazzaville République du Congo Institut Nationale de Recherche Agronomique (IRA) Brazzaville République du Congo Groupe Van den Berg Project Management B.V. Utrecht Netherlands Centre National d’Inventaire et d’Aménagement des Ressources Forestières et Fauniques (CIARF) Brazzaville République du Congo

Length-weight relationships and condition factors are among the commonly used parameters to link the length of a fish to its weight. The present study was initiated to find out the growth patterns and overweight status of 15 fish species in the Loémé basin in Mayombe, Republic of Congo. In the period from February 2020 to September 2021, sampling was carried out in eight stations, following a standardised capture method using four gillnets of 10, 12, 15, and 25 mm mesh size and a hawk net of 1.90 m radius with 10 mm mesh size. Length-weight relationships were calculated according to P = aLSb and the condition factor, using K = (P/LSb)* 100. A total of 1153 specimens representing 15 species, 10 genera and 6 families were recorded. The number of specimens ranged from 10 to 214 for Chrysichthys auratus and Enteromius camptacanthus, respectively. The allometry coefficient b minimum of 2.697 for Chromidotilapiamelaniae and maximum of 3.589 for Garraornata, with a mean of 3.03 ± 0.2 is significantly not different from 3 at the 0.05 probability threshold and indicates isometric growth for almost all species, except for E. camptacanthus where b = 2.858 was statistically different from 3 at the same threshold. The positive and high values of the coefficients of determination r2 = 0.787-0.989 of the species, obtained during this study, suggest that weight increases with size in the fish of the Loémé basin. The average condition factor varies from 0.524 ± 0.064 for G. ornata to 4.917 ± 0.440 for C. melaniae.

关键词： Fish Growth Overweight Loémé River Basin Lower Guinea

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The effect of propagation delay on the dynamic evolution of the Bitcoin blockchain

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digital Communications and Networks 2020年第2期6卷 157-166页

作者： Moustapha BA MOdAL’X(Laboratoire de Modélisation aléatoire)of UniversitéParis Nanterre(Paris X) MODAL’X is the Mathematics and Computer Sciences laboratory of UniversitéParis Nanterre(Paris X)ministerial label EA 3454UFR SEGMIdépartement Mathématiques-Informatique200 avenue de la République92000NanterreFrance

This paper analyzes the selfish-mine strategy in the Bitcoin blockchain introduced in 2013 by *** and *** strategy could be used by a colluding pool of miners to earn more than their fair share of the mining revenue and in consequence to force other honest miners to join them to decrease the variance of their revenues and make their monthly revenues more *** is a very dangerous dynamic that could allow the rogue pool of miners to go toward a majority by accumulating powers of news adherents and control the entire *** that the propagation delay of information between any two miners in the network,which is not negligible and follows a normal distribution with mean proportional to the physical distance between the two miners,and a constant variance independent of others'delays,we prove that no guarantee can be given about the success or failure of the selfish-mine attack because of the variability of information propagation in the network.

关键词： Blockchain Bitcoin Mining Selfish-mine attack Propagation delay of information

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Theoretical Study of the Reaction of (2, 2)-dichloro (Ethyl) Arylphosphine with Bis (2, 2)-dichloro (Ethyl) Arylphosphine by Hydrophosphination Regioselective by the dFT Method

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Computational Chemistry 2017年第3期5卷 113-128页

作者： Kouadio Valery Bohoussou Anoubilé Benié Mamadou Guy-Richard Koné Affi Baudelaire Kakou Kafoumba Bamba Nahossé Ziao Laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Université Nangui Abrogoua Abidjan République de C&ocirc te-d’Ivoire Laboratoire de Chimie Bio-Organique et de Substances Naturelles (LCBOSN) UFR SFA Université Nangui Abrogoua Abidjan République de C&ocirc te-d’Ivoire

For this work, we have selected two reactions for the formation of (2,2)-dichloro (ethyl) Arylphosphine and bis (2,2)-dichloro(ethyl)arylphosphine compounds by hydrophosphination. Global and local reactivity parameters, thermodynamic parameters of reactions, Transition states, the Fukui function, the local softness, the local electrophility index, and nucleophility index, Natural population analyses (NPA) and Mulliken (MK) were calculated with dFT method at B3LYP/6-311+G(d, p) level. The analysis of potential energy surfaces and the nature of the reaction mechanism have been determined. The various results obtained revealed that the addition of Arylphosphine is regiospecific. The phenylphosphine is more stable than the thiophenylphosphine. The theoretical results are consistent with experience.

关键词： Hydrophosphination Phosphine HOMO LUMO Fukui Index Transition State

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Mutations in Spike Gene of SARS-CoV-2 that Are Associated with a Higher Viral Load: A Clinical Case Study

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Case Reports in Clinical Medicine 2022年第11期11卷 474-486页

作者： Ibrahim Keita Garan dabo Lassina doumbia Youssouf diarra Ibrahim Traoré Mariam Traoré Lansana Sangaré Yacouba Toloba Mahamadou Alpha diallo djeneba Sy Andres H. Gutierrez Aliou Sissako Ibrahim Guindo Mohamed diallo Akory Ag Iknane Anne S. de Groot Ousmane Aliou Koita Laboratoire de Biologie Moléculaire Appliquée Université des Sciences Techniques et des Technologies de Bamako Bamako Mali Hô pital du Mali Ministère de la Santé Publique et du Développement Social Bamako Mali Centre Hospitalo-Universitaire du Point G Ministère de la Santé Publique et du Développement Social Bamako Mali EpiVax Inc. Providence USA Institut National de Santé publique Ministère de la Santé Publique et du Développement Social Bamako Mali Center for Vaccines and Immunology College of Veterinary Medicine University of Georgia Athens USA

Background: Quantitative PCR (qPCR) can be used to detect and quantify a load of a pathogen. It is a good indicator of the degree of transmissibility. While performing routine qPCR, we observed an unusually short cycle threshold (Ct) value of SARS-CoV-2 for a clinical specimen obtained in Bamako, Mali. This prompted us to sequence the short-cycle SARS-CoV-2 sample to identify potential mutations in the Spike gene (S gene) gene. Methods: Post-infection, Quantitative Reverse Transcription (qRT-PCR) was performed over a defined time course to estimate the Ct of the SARS-CoV-2 specimen collected from the patient. Sanger sequencing was done on the entire fragment of the S gene to identify mutations. Findings: Sanger sequencing revealed mutations in the lineage of interest, designated B.1.525 by Pango, and also known as “Eta” using the nomenclature defined by WHO. This variant was originally found in Nigeria and Italy. The four novel mutations identified in Eta (d228N, Y451N, I1172M, and C1250F) were otherwise observed with a low frequency worldwide. Although the initial Ct was 10 in the case study patient, he did not exhibit severe symptoms of SARS-CoV-2, for example, pneumonia. However, we observed a longer viral clearance period than usual, of 3 weeks. We note that as compared to SARS-CoV-2 samples obtained during the first peaks of SARS-CoV-2 infection in Mali, when the infection was at its peak in March 2020 (Ct = 30.4), circulating strains evaluated at the time the Eta sample was obtained demonstrated a lower mean Ct (Ct = 24). Conclusions: The short cycle threshold associated with this variant, and the temporal association with a decrease in the mean Ct in the region of Bamako, may indicate higher levels of transmissibility due to a circulating variant. This variant is a lineage of interest designated B.1.525 by Pango or Eta by WHO.

关键词： SARS-CoV-2 Variant Eta Ct Value Mali

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The antiangiogenic phloroglucinol hyperforin inhibits the secretion of proMMP-2, proMMP-9 and VEGF-A during apoptosis of primary acute myeloid leukemia cells

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Journal of Cancer Metastasis and Treatment 2021年第1期7卷 588-603页

作者： Faten Merhi Ruoping Tang Ollivier Legrand Florence Nguyen-Khac Santos A.Susin Brigitte Bauvois Centre de Recherche des Cordeliers INSERMSorbonne UniversitéUSPCUniversitéParis DescartesUniversitéParis DiderotParis F-75006France department of Life&Earth Sciences Faculty of Sciences(I)Lebanese UniversityBeirutLebanon Assistance publique-Hôpitaux de Paris Groupe Hospitalier Saint-AntoineService d’Hématologie CliniqueParis F-75012France Service Génétique des Tumeurs Département de Biologie et de Pathologie MédicaleGustave Roussy Cancer CamusVillejuif F-94805France Assistance publique-Hôpitaux de Paris Groupe Hospitalier Pitié-SalpêtrièreService d’Hématologie BiologiqueParis F-75013France.

Aim:Angiogenesis is observed in acute myeloid leukemia(AML).AML cells abnormally proliferate and are resistant to *** regulators of angiogenesis,VEGF-A and matrix metalloproteinases(MMPs)2 and 9 are markers of disease status in *** natural phloroglucinol hyperforin(HF)displays antitumoral properties of potential pharmacological ***,we investigated the effects of HF on MMP-2/9 and VEGF-A expression and survival of primary AML ***:Blood and bone marrow samples were collected in 45 patients with distinct subtypes defined by French American British classification,i.e.,M0,M1,M2,M3,M4,and *** of MMPs and VEGF-A in leukemic blood cells and culture supernatants were determined by RT-PCR,ELISA,and gelatin zymography(MMPs).The balance between cell death and survival was assessed by flow cytometry with analysis of phosphatidylserine externalization and caspase-3 ***:The administration of HF promoted a caspase-associated apoptosis in primary AML blasts(from blood and bone marrow),but not normal blood cells and *** addition,HF inhibited the levels of secreted proMMP-2,proMMP-9,and VEGF-A without altering *** induction of apoptosis by HF significantly paralleled the inhibition of MMP-2/9 and VEGF-A release by *** differences were seen in response to the deleterious effects of HF between AML cells of distinct ***:Our results suggest that HF,through its proapoptotic and potential antiangiogenic properties(by inhibiting MMP-2/9 and VEGF-A)on primary AML cells,might be a useful experimental agent,in combination with existing drugs,for new therapeutic approaches in the treatment of this incurable disease.

关键词： Acute myeloid leukemia apoptosis hyperforin matrix metalloproteinase VEGF secretion

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Immune therapies in pancreatic ductal adenocarcinoma: Where are we now?

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World Journal of Gastroenterology 2018年第20期24卷 2137-2151页

作者： Marc Hilmi Laurent Bartholin Cindy Neuzillet Service d'Oncologie Médicale H?pital Henri Mondor Assistance Publique-H?pitaux de Paris Université Paris Est Créteil Université de Lyon Université Claude Bernard Lyon 1 Inserm U1052 CNRS 5286Centre Léon Bérard Centre de Recherche en Cancérologie de Lyon

Pancreatic ductal adenocarcinoma(PdAC)is one of the deadliest cancers,mostly due to its resistance to *** these,checkpoint inhibitors(CPI)are inefficient when used as monotherapy,except in the case of a rare subset of tumors harboring microsatellite instability(des in the low immunogenicity and non-inflamed phenotype of *** abundant stroma generates a hypoxic microenvironment and drives the recruitment of immunosuppressive cells through cancerassociated-fibroblast activation and transforming growth factorβ*** strategies have recently been developed to overcome this immunosuppressive *** therapies involving CPI aim at increasing tumor immunogenicity and promoting the recruitment and activation of effector T *** studies are therefore exploring the association of CPI with vaccines,oncolytic viruses,MEK inhibitors,cytokine inhibitors,and hypoxia-and stroma-targeting *** T-cell transfer is also under ***,translational studies on tumor tissue and blood,prior to and during treatment may lead to the identification of biomarkers with predictive value for both clinical outcome and response to immunotherapy.

关键词： drug therapy combination Immunology Hypoxia Checkpoint inhibitor Inflammation Pancreatic cancer Tumor-infiltrating lymphocyte Transforming growth factorβ Tumor microenvironment

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Minimum and Maximum Temperature Trends in Congo-Brazzaville: 1932-2010

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Atmospheric and Climate Sciences 2014年第3期4卷 404-430页

作者： Gaston Samba dominique Nganga Centre de Recherches et d’études sur l’Environnement (CR2E) Université Marien Ngouabi Brazzaville République du Congo

Maximum and minimum temperatures time series of Congo-Brazzaville are analyzed for trend and discontinuities over the period 1932 to 2010. Temperatures series show an irregular increase. A total of 8 synoptic stations show positive trends in their annual mean maximum temperature series, and 7 of them are significant, with higher trends for urban stations. Annual mean minimum temperature showed 6 stations having positive trends. This increase is in relation with observations at regional scale. However, the differences are observed between large towns (Brazzaville and Pointe-Noire), and small or rural towns (dolisie, Sibiti, Impfondo, djambala). Trends in diurnal temperature range (dTR) are large positive trends in maximum temperature that are mainly observed in cities. The curve of dTR shows a decreasing trend which indicates the increasing of minimum temperatures. The effects of urbanization on temperature trends are investigated. Most stations regarded as urban stations are still useful for trend analysis;being situated on the suburban of the studied cities, they are therefore, not substantially influenced by the urban heat island.

关键词： Congo Republic Temperatures Maximum and Minimum Temperature Trends

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How to Reduce Unnecessary Invasive Angiograms When Patients Are Initially Evaluated by Coronary Computed Tomography?

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Advances in Computed Tomography 2013年第1期2卷 13-19页

作者： Edouard Cheneau Bruno Vahdat Noemie Resseguier Laurent Bernard Annamaria Molon Roch Giorgi dimitri Panagides Service de Cardiologie Clinique BouchardMarseilleFrance Service de Sante publique et d’Information Medicale Hopital de la TimoneMarseilleFrance

Purpose:When Coronary Computed Tomography (CCT) detects coronary obstruction, patients are regularly referred to invasive angiogram. With higher sensitivity than specificity, CCT might induce unnecessary angiograms (“false positive CCT”). We sought to determine the patients and CCT findings associated with false positive CCT. Methods: Patients were prospectively referred to CCT with a 64-slice CT scan for suspected CAd. Inclusion criteria were: 1) clinically suspected angina pectoris;or 2) suspected silent ischemia on resting EKG. Exclusion criteria were acute coronary syndrome and non sinus rhythm. Invasive coronary angiogram (ICA) was performed on the basis of CCT findings (stenosis >50%). Analysis was performed on a per patient basis. Results: Out of 702 patients, 228 had suspected significant stenosis by CCT and ICA was performed in 176 patients. Coronary stenosis >50% was not confirmed by ICA in 44 (25%). In multivariate analysis, we observed that atypical angina (OR 3.63,CI 1.43-9.66), silent ischemia (OR 5.11, CI 1.89-14.6) and number of suspected stenosed arteries by CCT (OR 1.81, CI 1.15-2.94) were independently predictive of false positive CCT (p Conclusions:Performing CCT for atypical angina or silent ischemia is associated with higher rate of unnecessary invasive coronary angiograms. We failed to identify lesions characteristics prone to be “false positive” of CCT.

关键词： Angina Coronary disease diagnosis CCT

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Flavonoid Glycosides from the Leaves of Glyphaea brevis

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Open Journal of Applied Sciences 2022年第7期12卷 1296-1303页

作者： Philomène Akoua Yao-Kouassi diane Apie Patricia Gossan Abdulmagid Alabdul Magid Agathe Martinez Charlotte Sayagh Laurence Voutquenne-Nazabadioko UFR Sciences des Structures de la Matière et de Technologie Laboratoire de Constitution et Réaction de la Matière Université Félix Houphou&euml t-Boigny Abidjan République de C&ocirc te d’Ivoire Université de San Pedro San Pedro République de C&ouml te d’Ivoire Université Péléforo Gon Coulibaly de Korhogo Korhogo République de C&ouml te d’Ivoire CNRS ICMR UMR 7312 Université de Reims Champagne-Ardenne Reims France

A new flavonoid, acacetin-7-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucuronopyranoside (1), together with four known flavonoids, apigenin-7-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucuronopyranoside (2), acacetin (3), acacetin-7-O-β-d-glucuronide (4) and genkwanin-5-O-primveroside (5) were isolated from the leaves of Glyphaea brevis. Their structures were elucidated by spectroscopic techniques. The isolated compounds (1 - 5) were tested for their antioxidant activity using the 1,1-diphenyl-2-picrylhydrazyl (dPPH) radical scavenging assay. The tested compounds showed slight negative antioxidant activities against dPPH radicals.

关键词： Glyphaea brevis Malvaceae Aca-cetin-7-O-β-d-Glucopyranosyl-(1→2)-β-d-Glucuronopyranoside

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Consequences of metabolic syndrome on postoperative outcomes after pancreaticoduodenectomy

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World Journal of Gastroenterology 2017年第17期23卷 3142-3149页

作者： Alban Zarzavadjian Le Bian david Fuks Sophie Chopinet Sébastien Gaujoux Manuela Cesaretti Renato Costi Ajay P Belgaumkar Claude Smadja Brice Gayet department of digestive Surgery Centre Hospitalier Simone Veil Laboratory of Medical Ethics and Legal Medicine University Paris Descartes department of digestive disease-Institut Mutualiste Montsouris UniversitéParis descartes department of digestive Surgery Assistance PubliqueHopitaux de Paris Hopital Cochin department of digestive Surgery Assistance PubliqueHopitaux de Paris Hopital Antoine Béclère157 rue de la Porte Trivaux Boulevard Général Leclerc

AIM To analyze immediate postoperative outcomes after pancreaticoduodenectomy regarding metabolic *** In two academic centers, postoperative outcomes of patients undergoing pancreaticoduodenectomy from 2002 to 2014 were prospectively recorded. Patients presenting with metabolic syndrome [defined as at least three criteria among overweight(BMI ≥ 28 kg/m2), diabetes mellitus, arterial hypertension and dyslipidemia] were compared to patients without metabolic *** Among 270 consecutive patients, 29(11%) presented with metabolic syndrome. In univariable analysis, patients with metabolic syndrome were significantly older(69.4 years vs 62.5 years, P = 0.003) and presented more frequently with soft pancreas(72% vs 22%, P = 0.0001). In-hospital morbidity(83% vs 71%) and mortality(7% vs 6%) did not differ in the two groups so as pancreatic fistula rate(45% vs 30%, P = 0.079) and severity of pancreatic fistula(P = 0.257). In multivariable analysis, soft pancreas texture(P = 0.001), pancreatic duct diameter d BMI > 30 kg/m2(P = 0.041) were identified as independent risk factors of pancreatic fistula after pancreaticoduodenectomy, but not metabolic *** In spite of logical reasoning and appropriate methodology, present series suggests that metabolic syndrome does not jeopardize postoperative outcomes after pancreaticoduodenectomy. Therefore, definition of metabolic syndrome seems to be inappropriate and fatty pancreas needs to be assessed with an international consensual histopathological classification.

关键词： Soft pancreas Postoperative outcomes Metabolic syndrome Pancreaticoduodenectomy

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