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Multi-walled carbon nanotubes covalently functionalized by axially coordinated metal-porphyrins： Facile syntheses and temporally dependent optical performance

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Nano Research 2016年第2期9卷 458-472页

作者： Aijian Wang Jingbao Song Zhipeng Huang Yinglin Song Wang Yu Huanli Dong Wenping Hu marie p. Cifuentes Mark G. Humphrey Long Zhang Jianda Shao Chi Zhang China-Australia Joint Research Center for Functional Molecular Materials Scientific Research Academy Jiangsu UniversityZhenjiang 212013 China China-Australia Joint Research Center for Functional Molecular Materials School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China Key Laboratory of Materials for High-power Laser Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China School of physical Science and Technology Soochow University Suzhou 215006 China Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China Research School of Chemistry Australian National University Canberra ACT2601 Australia

Axially coordinated metal-porphyrin-functionalized multi-walled carbon nanotube （MWCNT） nanohybrids were prepared via two different synthetic approaches （a one-pot 1,3-dipolar cycloaddition reaction and a stepwise approach that involved 1,3-dipolar cycloaddition followed by nucleophilic substitution）, and characterized through spectroscopic techniques. Attachment of the tin porphyrins to the surface of the MWCNTs significantly improves their solubility and ease of processing. These axially coordinated （5,10,15,20-tetraphenylporphyrinato）tin（Ⅳ）（SnTpp）- MWCNTs exhibit significant fluorescence quenching. The third-order nonlinear optical properties of the resultant nanohybrids were studied by using the Z-scan technique at 532 nm with both nanosecond and picosecond laser pulses. The results show that the nanohybrids exhibit significant reverse saturable absorption or saturable absorption when nanosecond or picosecond pulses, respectively, are employed. Improvement in the nanosecond regime nonlinear absorption is observed on proceeding to the nanohybrids and is ascribed to a combination of the outstanding properties of MWCNTs and the chemically attached metal-porphyrins.

关键词： metal-porphyrin axially coordinated multi-walled carbon nanotubes facile syntheses optical performance cycloaddition

Relationships between mucinous gastric carcinoma, MUC2 expression and survival

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World Journal of Gastroenterology 2006年第21期12卷 3324-3331页

作者： Emmanuelle Leteurtre Farid Zerimech Guillaume piessen Agnès Wacrenier Xavier Leroy marie-Christine Copin Christophe mariette Jean-p.erre Aubert Nicole porchet marie-p.erre Buisine INSERM U560 59045Lille cedexFrance Service d'Anatomie et Cytologie pabologiques pôle Biologie-pathogie Pac Eurasanté.CHR-U de Lille59037 Lille cedexFrance Service de Biochimie et Biologie Moléculaire CHR-U de Lille59037 Lille cedexFrance Facultéde Médecine H.Warembourg 59045 Lille cedexFrance Service.de Chirurgie Digetive et Générale CAEB CHR-U de Lille59045 Lille cedexFrance

AIM:To investigate the expression of the four secreted gel-forming mucins(MUC2,MUCSAC,MUCSB and MUC6)in a series of gastric carcinomas,classified according Laurén's,Mulligan's,WHO and Goseki's classifications,with special attention to all the different components(major and minor)present in tumors and to follow up clinical ***:Expression of MUC2,MUC5AC,MUC5B and MUC6 was investigated using immunohistochemistry and in situ ***:Expression of secreted gel-forming mucins in gastric carcinoma was particularly complex,each mucin being not restricted to any histopathological type even considering all components(major and minor)present in a given *** was a worst survival in patients with a higher content of mucus(GosekiⅡorⅣ)and high positive MUC2 ***:Complexity of mucin gene expression patterns in gastric cancer may reflect a precise state of differentiation at the cell level not recognized in used morphologic classification *** expression of MUC2 was nevertheless associated with mucinous subtype of the WHO classification and with groupⅡof Goseki's classification identified by the major component of a particular *** quantity and quality of mucus were related to survival.

关键词： Gastric cancer Secreted gel-forming mucin MUC Immunohistochemistry in situ hybridization Survival

Detecting the presence of natural forests using airborne laser scanning data

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Forest Ecosystems 2023年第6期10卷 668-680页

作者： marie-Claude Jutras-perreault Terje Gobakken Erik Næsset Hans OleØrka Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesNMBUP.O.BoxNO-1432ÅsNorway

Centuries of forest exploitation have caused significant loss of natural forests in Europe,leading to a decline in populations for many *** prevent further loss in biodiversity,the Norwegian government has set a target of protecting 10%of the forested ***,recent data from the National Forest Inventory(NFI)reveals that less than 2%of Norway's forested area consists of natural *** identify forests with high conservation value,we used vertical and horizontal variables derived from airborne laser scanning(ALS)data,along with NFI plot *** study aimed to predict the presence of natural forests across three counties in southeastern Norway,using three different definitions:pristine,near-natural,and semi-natural *** forests are scarce,and their underrepresentation in field reference data can compromise the accuracy of the *** address this,we assessed the potential gain of including additional field data specifically targeting natural forests to achieve a better balance in the ***,we examined the impact of stratifying the data by dominant tree species on the performance of the *** results revealed that semi-natural forests were the most accurately predicted,followed by near-natural and pristine forests,with Matthews correlation coefficient values of 0.32,0.24,and 0.17,*** additional field data did not improve the ***,stratification by species improved the accuracy of predictions for near-natural and semi-natural forests,while reducing accuracy for pristine *** use of horizontal variables did not improve the *** study demonstrates the potential of ALS data in identifying forests with high conservation *** provides a basis for further research on the use of ALS data for the detection and conservation of natural forests,offering valuable insights to guide future forest preservation efforts.

关键词： Natural forest ALS Naturalness Vertical variables Horizontal variables Biodiversity Forest condition Ecosystem services

Impact of nanocrystallinity segregation on the growth and morphology of nanocrystal superlattices

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Nano Research 2013年第8期6卷 611-618页

作者： Yanfen Wan Herve portals Nicolas Goubet Alain Mermet marie-paule pileni Université p.erre et marie Curie paris 6 UMR 7070 LM2N 8P 52 4 place Jussieu 75005 Paris France Centre National de la Recherche Scientifique Unitd Mixte de Recherche 7070 LM2N 4 place Jussieu 75005 Paris France Université Lyon I Institut Lumiére Matiére Unité Mixte de Recherche 5306 CNRS Bāt. A. Kastler 10 rueAda Byron 69622 Villeurbanne France

A colloidal solution of 5 nm Au tetradecanethiol-coated nanoparticles is syn-thesized. After fast evaporation of one drop, ordered monolayers both composed of single domain and polycrystalline nanocrystals are obtained. On increasing the amount of materials and the evaporation time, nanocrystal films with irregular outlines are produced together with close-packed 3D superlattices exhibiting a truncated-tetrahedral shape. Using low-frequency micro-Raman scattering spectroscopy and electron microscopy the building block nanocrystallinity is characterized. Spontaneous nanocrystallinity segregation is revealed： the truncated-tetrahedral supracrystals are shown to mainly contain single domain building blocks while the supracrystalline films are composed of a mixture of single domain and polycrystalline nanocrystals. This observation points out the correlation between the nanocrystallinity segregation involved in the growth of the nanocrystal superlattices and their morphology.

关键词： supracrystals close-packed self-assembly metal nanoparticles Raman scatteringspectroscopy

Brain natriuretic peptide is a potent vasodilator in aged human microcircula- tion and shows a blunted response in heart failure patients

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Journal of Geriatric Cardiology 2014年第1期11卷 50-56页

作者： marie-Louise Edvinsson Erik Uddman Lars Edvinsson Sven E. Andersson Department of Emergency and Internal Medicine Institute of Clinical Sciences Lund University Lund University Hospital SE- 221 85 Lund Sweden

Background Brain natriuretic peptide （BNp） is normally present in low levels in the circulation, but it is elevated in parallel with the degree of congestion in heart failure subjects （CHF）. BNp has natriuretic effects and is a potent vasodilator. It is suggested that BNp could be a therapeutic alternative in CHF. However, we postulated that the high levels of circulating BNp in CHF may downregulate the response of microvascular natriuretic receptors. This was tested by comparing 15 CHF patients （BNp 〉 3000 ng/L） with 10 matched, healthy controls. Methods Cutaneous microvascular blood flow in the forearm was measured by laser Doppler Flowmetry. Local heating （＋44°C, 10 min） was used to evoke a maximum local dilator response. Results Non-invasive iontophoretic administration of either BNp or acetylcholine （ACh）, a known endothelium-dependent dilator, elicited an increase in local flow. The nitric oxide synthase inhibitor, l-N-Arginine- methyl-ester （L-NAME）, blocked the BNp response （in controls）. Interestingly, responses to BNp in CHF patients were reduced to about one third of those seen in healthy controls （increase in flow： 251% in CHF vs. 908% in controls; p 〈 0.001）. In contrast, the vasodilator responses to ACh and to local heating were only somewhat attenuated in CHF patients. Thus, dilator capacity and nitric oxide signalling were not af- fected to the same extent as BNp-mediated dilation, indicating a specific downregulation of the latter response. Conclusions The findings show for the first time that microvascular responses to BNp are markedly reduced in CHF patients. This is consistent with the hypothesis of BNp receptor function is downregulated in CHF.

关键词： Heart failure Cutaneous microcirculation Endothelial responses Acetylcholine, Brain natriuretic peptide Nitric oxide

Mass Screening Using Antigenic and Molecular Diagnostic Tests of COVID-19 in Bangui at the Beginning of the Second Wave in July 2021

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Journal of Tuberculosis Research 2024年第1期12卷 1-12页

作者： Clotaire Donatien Rafaï marie-Roseline Darnycka Belizaire p.erre Somse Wilfrid Sylvain Nambei Ernest Lango-Yaya Oscar Senzongo Luc Salva Hereidebona Ulrich Jeffrey Kotemossoua Rabbi Mermoz Senekian Simon pounguinza Christian-Diamant Mossoro-Kpinde Alain Le Faou Jean De Dieu Longo François-Xavier Mbopi-Keou Gérard Grésenguet Boniface Koffi National Laboratory of Clinical Biology and public Health Bangui Central African Republic Faculty of Health Sciences University of Bangui Bangui Central African Republic World Health Organization Bangui Central African Republic Ministry of Health and population Bangui Central African Republic Faculty of Medicine Maieutic and Health Sciences University of Lorraine Pole Brabois Santé Nancy France Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroun

Objective: COVID-19 surveillance was established as early as March 2020 in the Central African Republic (CAR), after the WHO statement relating to the identification of several cases outside China. However, given the non-performing molecular biology technical platform in many developing countries in sub-Saharan Africa, the second wave promised to be surprising and formidable. In this context, a mass survey was launched in Bangui to determine the prevalence of COVID-19. patients and Methods: From March 18 to April 2, 2021, a mass screening campaign took place in tourist places, companies and the main hospital infrastructures. Nasopharyngeal swab samples were collected from participants with and without symptoms of Influenza-like illness (ILI) and stored in VTM tubes. The Ag (COVID-19) and RT-pCR tests were carried out in Bangui at the LNBCSp. The sequencing of RT-pCR SARS-CoV-2 positives was carried out at the INRB. Results: We included 1480 participants of whom 33 (2.23%) were SARS-COV-2 positive, of whom 24 were male and 9 female. This sex difference was statistically significant (p = 0.012) as the sex ratio M/F was 1.09. Sampling sites located in the 1st arrondissement were the most prolific (p = 0.006) and were sequenced. In addition to the analysis of the 33 samples from the predefined sites under study, 17 control sequences from the provinces generated during the same period are added. We detected 2 Variants Of Concern (VOC) including the predominant B.1.620 (43.86%) followed by B.1.1.7 or Alpha (5.10%). Conclusion: The study showed the importance of surveillance and the availability of means of diagnosis of COVID-19. The identified risk factors were sex and sampling site. This study has shown the importance of setting up sentinel sites for COVID-19 surveillance in all regions of the country and the appropriate use of the anti-COVID-19 vaccine.

关键词： COVID-19 Variants Central African Republic

The common MTHFR C677T and A1298C variants are not associated with the risk of non-syndromic cleft lip/palate in northern Venezuela

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Journal of Genetics and Genomics 2009年第5期36卷 283-288页

作者： Mehmet A.Szen marie M.Tolarova Richard A.Spritz Department of Medical Biology School of MedicineAfyon Kocatepe UniversityAfyonkarahisar03200 Turkey Human Medical Genetics program University of Colorado DenverAnschutz Medical CampusAuroraCO 80045USA Department of Orthodontics University of the PacificSan FranciscoCA 94115USA

Non-syndromic cleft lip with or without cleft palate （nsCL/p） is among the most common major birth defects, with complex inheritance involving multiple genes and environmental factors. Numerous studies of MTHFR, encoding methylenetetrahydrofolate reductase, which catalyzes the rate-limiting step of folic acid biosynthesis, have shown inconsistent association of two common hypomorphic allelic variants, C677T and A1298C, in nsCL/p patients and, in some cases, their mothers. We have studied the MTHFR C677T and A1298C polymorphisms in nsCL/p patients, their mothers, and population-matched controls from northern Venezuela. We found no evidence for contribution of the MTHFR C677T and A1298C variants to the risk of nsCL/p in northern Venezuela. Overall, our findings fail to support a causal role of either the MTHFR C677T or A 1298C variants in the pathogenesis of nsCL/p in northern Venezuela.

关键词： cleft lip cleft palate methylenetetrahydrofolate reductase folic acid MTHFR polymorphisms

Core-shell particles of C-doped CdS and graphene: A noble metal-free approach for efficient photocatalytic H_(2) generation

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Green Energy & Environment 2020年第4期5卷 461-472页

作者： Muhammad Zubair Estelle marie M.Vanhaecke Ingeborg-Helene Svenum Magnus RФnning Jia Yang Department of Chemical Engineering Norwegian University of Science and Technology(NTNU)Sem Sælands vei 4TrondheimNO7491Norway SINTEF Industry P.O.Box 4760 TorgardenTrondheimNO7465Norway

To achieve efficient photocatalytic H_(2) generation from water using earth-abundant and cost-effective materials,a simple synthesis method for carbon-doped CdS particles wrapped with graphene(C-doped CdS@G)is *** doping effect and the application of graphene as cocatalyst for CdS is studied for photocatalytic H_(2) *** most active sample consists of CdS and graphene(CdS-0.15G)exhibits promising photocatalytic activity,producing 3.12 mmol g^-(1) h^-(1) of H_(2) under simulated solar light which is^4.6 times superior than pure CdS nanoparticles giving an apparent quantum efficiency(AQY)of 11.7%.The enhanced photocatalytic activity for H_(2) generation is associated to the narrowing of the bandgap,enhanced light absorption,fast interfacial charge transfer,and higher carrier density(N_(D))in C-doped CdS@G *** is achieved by C doping in CdS nanoparticles and the formation of a graphene shell over the C-doped CdS *** stability test,the spent catalysts sample was also characterized to investigate the nanostructure.

关键词： C-doped CdS@G Core-shell nanostructure photocatalytic H2 generation Graphene Carbon doping in CdS Bandgap narrowing

INF-γ and IL-2 profile as Therapeutic Markers in Tuberculosis patients at the Jamot Hospital of Yaounde-Cameroon

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Journal of Tuberculosis Research 2024年第2期12卷 119-128页

作者： Alexandra Emmanuelle Membangbi Jacky Njiki-Bikoï Esther Del-Florence Moni Ndedi Donatien Serge Mbaga Elsa Nguiffo Makue André Chris Mikangue Mbongue Koko-Ta Ladiff Sharonne Martha Mesembe Justin Olivier Essindi Aïcha Ngoutane Arnaud Franck Elang Sabine Aimée Touangnou-Chamda George Ikomey Mondinde Eric Walter perfura-Yone marie Joseph Nkodo Mindimi Sara Honorine Riwom Essama Department of Microbiology The University of Yaound 1 Yaound Cameroon Center for the Study and Control of Communicable Diseases (CSCCD) Yaound Cameroon The Institute for Medical Research and Medicinal plants Studies Yaound Cameroon Faculty of Medicine and Biomedical Sciences The University of Yaound I Yaound Cameroon The pneumology Department Jamot Hospital of Yaound Yaound Cameroon

Background: Tuberculosis (TB) is one of the top lethal infectious diseases worldwide. In recent years, interferon-γ (INF-γ) release assays (IGRAs) have been established as routine tests for diagnosing TB infection. However, produced INF-γ assessment cannot permit to distinguish active ATB from latent TB infection (LTBI), especially in TB epidemic areas. In addition to IFN-γ, interleukin-2 (IL-2), secreted by activated T cells, is involved in immune response against Mycobacterium tuberculosis. This could be involved in the follow up of treatment response. The aim of our study was to determine IFN-γ and IL2 cytokines profiles of patients under antituberculosis treatment. Materials and Methods: A six months’ cross-sectional study was conducted at the Jamot Hospital of Yaoundé, from May to August 2021. Sociodemographic and clinical data as well as 5 mL of blood were collected from each participant. INF-γ and IL-2 were determined using indirect Enzyme linked Immuno-Sorbent Assay (ELISA) according to the manufacturer’s recommendations and spectrum exam in combination with radiography and GeneXpert were used as standard. p-values Results: The results showed that men were more infected 14/61 (31.8%) with a high presence in active and resistant TB groups. The mean age was 41.3 ± 13.1 years with a 95% CI = [38.2 - 44.7], the age group with the highest infection rate was ranged between 31 and 40 years. The IL-2 and INF-γ means were respectively 327.6 ± 160.6 pg/mL and 26.6 ± 13.0 pg/mL in ATB patients, 251.1 ± 30.9 pg/mL and 21.4 ± 9.2 pg/mL in patients with resistant tuberculosis, while it was 149.3 ± 93.3 pg/mL and 17.9 ± 9.4 pg/mL in cured patients, 15.1 ± 8.4 pg/mL and 5.3 ± 2.6 pg/mL in participants presumed healthy (p γ and IL-2rates were observed between the different groups. Conclusion: Monitoring the serum levels of INF-γ and IL-2 would be useful for the follow-up of anti-tuberculosis patients, particularly in the both cytokines association case.

关键词： Tuberculosis Antituberculosis Treatment INF-γ IL-2 ELISA