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Gravity tectonics controls on reservoir-scale sandbodies:Insights from 3D seismic geomorphology of the canyons buried in the upper slope of the Eastern Niger delta basin
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作者 Vivian O.Oguadinma Jean-Yves Reynaud +4 位作者 Vincent Delhaye-Prat Tony Akpi Scott Thackrey Ademola Lanisa Massimo Dall’Asta 《Energy Geoscience》 EI 2024年第3期244-260,共17页
High-resolution 3D seismic data analysis was integrated with a calibrated well and biostratigraphy data to present the first overview of a buried Pleistocene canyon system on the upper slope of the eastern Niger Delta... High-resolution 3D seismic data analysis was integrated with a calibrated well and biostratigraphy data to present the first overview of a buried Pleistocene canyon system on the upper slope of the eastern Niger Delta,the Galabor Canyon.Attribute maps of specific horizons allow documenting the changing morphologies and infill lithologies of two main branches of the canyon through two stages of activity separated by a reference horizon dated at 0.99 Ma based on well calibration.At the upper slope,growth faults dissect the canyon heads,the catchment of which encroaches a network of valleys incised on the outer shelf.The canyon fill is composed of muddy channels and mass-transport deposits,largely derived from the collapse of canyon walls and sand-rich bodies forming a tract sourced by shelf-edge deltas at the outlet of the incised valleys.High-density turbiditic processes likely control the distribution of sand bodies along the canyon,ranging from tributary fans on the upper slope to 6 km-wide meander belts on the middle slope.The sandy deposits accumulate in minibasins formed along the canyon path,downstream of the subsiding hanging wall of the growth faults and upstream of shale ridges that damp the flow in the canyon.These results show that canyons can be major targets for sand reservoir exploration on the upper slope of large muddy deltas. 展开更多
关键词 GEOMORPHOLOGY Submarine canyon 3D seismic Fault Shale ridge RESERVOIR Channel
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Synergistic solvent extraction of boric acid by trioctylamine and 2-hydroxydodecanoic acid
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作者 Zhuojun Jiang Yufeng Liang +5 位作者 Shuyao Xiong Guo Li Qian Zhang Benzheng Xia Liangrong Yang Zheng Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期117-126,共10页
A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of li... A synergistic solvent extraction system comprising trioctylamine(TOA)and ligands with hydroxyl and carboxyl groups can efficiently recover boric acid(H_(3)BO_(3))and separate boron isotopes.However,the structure of ligands might impact H_(3)BO_(3) extraction,boron isotope separation,and solvent loss,which has not been thoroughly investigated.This study initially evaluated the influence of ligand's type,pKa,and substituents on H_(3)BO_(3) extraction efficiency,as well as the impact of the B_((4))-O structure(boron is bound to four oxygen atoms)in the organic phase on isotope separation efficiency.Subsequently,by synthesizing the highly hydrophobic 2-hydroxydodecanoic acid(HYA),the extraction performance and mechanism of the TOA/HYA system were investigated.The findings highlight the superior extraction efficiency when employing di-phenolic hydroxyl,phenolic hydroxyl + carbinol hydroxyl,and alcoholic hydroxyl + carboxyl ligands compared to phenolic hydroxyl + carboxyl,phenolic hydroxyl + ethanol hydroxyl,diol hydroxyl,and dicarboxylic ligands.The organic phase anion complex,exclusively comprising the B_((4))-O structure,enhances isotope separation effectiveness.The TOA/HYA system achieves an 80%single-stage extraction efficiency for H_(3)BO_(3).H_(3)BO_(3) and HYA are extracted into the organic phase at a ratio of 1:2,with the anion complex solely containing the B_((4))-O structure.This study paves the way for the construction of novel boric acid extraction and boron isotope separation systems. 展开更多
关键词 Boric acid 2-Hydroxydodecanoic acid Synergistic extraction Coordination mechanism Boron isotope separation
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Solid-state NMR of vulcanized natural rubber/butadiene rubber blends:Local organization and cross-linking heterogeneities This article is part of the virtual special issue“Solid-state NMR studies on polymers and biological solids”
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作者 Pierre Daniel Cristina Coelho-Diogo +3 位作者 Valérie Gaucher Grégory Stoclet Clément Robin Cédric Lorthioir 《Magnetic Resonance Letters》 2024年第4期49-61,共13页
Elastomer blends,among which natural rubber(NR)and butadiene rubber(BR),are involved in many components of the automotive/tire industry.A comprehensive understanding of their mechanical behavior requires,among other f... Elastomer blends,among which natural rubber(NR)and butadiene rubber(BR),are involved in many components of the automotive/tire industry.A comprehensive understanding of their mechanical behavior requires,among other features,a detailed description of the crosslink density in these mixtures.In the case of vulcanized immiscible blends,the distribution of the cross-link density within each of the NR-and BR-rich domains is key information,but difficult to determine using the conventional approaches used for one-component crosslinked elastomers.In this study,the vulcanization within NR/BR blends is investigated using a robust^(1)H double-quantum(DQ)MAS recoupling experiment,BaBa-xy16.Two kinds of cross-linked NR/BR blends were considered with two different microstructures for the BR component.The bulk organization of the resulting blends was first probed by analyzing the^(1)H spin-lattice relaxation behavior.In a second step,BaBa-xy16 was used to investigate,in a selective way,the cross-link heterogeneities within NR/BR blends.In particular,for immiscible NR/BR mixtures,the distribution of the cross-link density between both phases was compared and the observed differences were discussed. 展开更多
关键词 RUBBERS Blends Cross-linking 1H solid-state NMR Relaxation Double-quantum NMR Dipolar recoupling
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Tree structure and diversity shape the biomass of primary temperate mountain forests
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作者 Dheeraj Ralhan Ruffy Rodrigo +14 位作者 Heather Keith Annemiek Irene Stegehuis Jakob Pavlin Yumei Jiang Milos Rydval Juliana Nogueira Alexandre Fruleux Marek Svitok Martin Mikolas Daniel Kozak Martin Dusatko Pavel Janda Oleh Chaskovsky Catalin-Constantin Roibu Miroslav Svoboda 《Forest Ecosystems》 SCIE CSCD 2024年第4期568-579,共12页
Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of ... Primary forests are spatially diverse terrestrial ecosystems with unique characteristics,being naturally regenerative and heterogeneous,which supports the stability of their carbon storage through the accumulation of live and dead biomass.Yet,little is known about the interactions between biomass stocks,tree genus diversity and structure across a temperate montane primary forest.Here,we investigated the relationship between tree structure(variability in basal area and tree size),genus-level diversity(abundance,tree diversity)and biomass stocks in temperate primary mountain forests across Central and Eastern Europe.We used inventory data from726 permanent sample plots from mixed beech and spruce across the Carpathian Mountains.We used nonlinear regression to analyse the spatial variability in forest biomass,structure,and genus-level diversity and how they interact with plot-level tree age,disturbances,temperature and altitude.We found that the combined effects of genus and structural indices were important for addressing the variability in biomass across different spatial scales.Local processes in disturbance regimes and uneven tree age support forest hete rogeneity and the accumulation of live and dead biomass through the natural regeneration,growth and decay of the forest ecosystem.Structural complexities in basal area index,supporte d by genus-level abundance,positively influence total biomass stocks,which was modulated by tree age and disturbances.Spruce forests showed higher tree density and basal area than mixed beech forests,though mixed beech still contributes significantly to biomass across landscapes.Forest heterogeneity was strongly influenced by complexities in forest composition(tree genus diversity,structure).We addressed the importance of primary forests as stable carbon stores,achieved through structure and diversity.Safeguarding such ecosystems is critical for ensuring the stability of the primary forest,carbon store and biodiversity into the future. 展开更多
关键词 Biodiversity indicators Biomass carbon stock Ecosystem functioning Forest composition Primary forest structure Tree size distribution
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Efficacy and tolerability of chitin-glucan combined with simethicone(GASTRAP^(■)DIRECT)in irritable bowel syndrome:A prospective,open-label,multicenter study
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作者 Nathalie Talbodec Pauline Le Roy +14 位作者 Peggy Fournier Benoit Lesage Elodie Lepoutre François Castex Jean Michel Godchaux Lionel Vandeville Benjamin Bismuth Xavier Lesage Pauline Bayart Michael Genin Christel Rousseaux Veronique Maquet Salvatore Modica Pierre Desreumaux Caroline Valibouze 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 2024年第3期10-22,共13页
BACKGROUND Irritable bowel syndrome(IBS),defined according to the Rome IV diagnostic criteria,is a chronic functional gastrointestinal disorder characterized by recurrent abdominal pain related to altered bowel habits... BACKGROUND Irritable bowel syndrome(IBS),defined according to the Rome IV diagnostic criteria,is a chronic functional gastrointestinal disorder characterized by recurrent abdominal pain related to altered bowel habits.First-line recommended treatments are limited to combining drugs targeting predominant symptoms,particularly pain(antispasmodics),constipation(laxatives),and diarrhea(loperamide),yielding only a limited therapeutic gain.GASTRAP^(■)DIRECT is a class IIa medical formulation composed of a combination of chitin-glucan and simethicone indicated for the symptomatic treatment of gas-related gastrointestinal disorders by combining different mechanisms of action.AIM To evaluate the efficacy,tolerability,and safety of 4-week GASTRAP^(■)DIRECT treatment in patients with IBS.METHODS In this prospective,multicenter,open-label trial,120 patients with IBS received three sticks of GASTRAP^(■)DIRECT(1.5 g/d of chitin-glucan and 0.75 mg/d of simethicone)per day for 4 weeks.The primary endpoint was the responder rate,defined as the number of patients whose abdominal pain score decreased by≥30%from baseline to week(W)4.The analysis was performed using the per-protocol set.Cardinal symptoms,impact of global symptoms on daily life,change in stool consistency,and improvement in defecatory disorders were evaluated.RESULTS Overall,100 patients were evaluated.At W4,67%(95%CI:57-75)showed improvement in abdominal pain(score:5.8±2.4 vs 2.9±2.0,P<0.0001).Similar improvements were observed for bloating[8.0±1.7 vs 4.7±2.9,P<0.0001;60%(95%CI:50-70)responders],abdominal distension[7.2±2.1 vs 4.4±3.1,P<0.0001;53%(95%CI:43-63)responders],and impact of global symptoms on daily life[7.1±2.0 vs 4.6±2.9,P<0.0001;54%(95%CI:44-64)responders].Stool consistency improved in most patients(90%and 57%for patients with liquid and hard stools,respectively).Overall,42%of patients with defecatory disorders reported very much/considerable improvements by W2.No severe adverse event occurred,and tolerability was rated“good”or“very good”by 93%of patients.CONCLUSION GASTRAP^(■)DIRECT is safe and well tolerated,alleviating IBS symptoms rapidly in 2 weeks.This open-label study suggests that the combination of chitin-glucan and simethicone could be beneficial in patients with IBS. 展开更多
关键词 Chitin-glucan Irritable bowel syndrome Abdominal pain FLATULENCE Defecatory disorders Stool consistency Natural non-pharmacological treatment
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Advances in peridynamics modeling of deformation and fracturing of brittle geomaterials
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作者 Feng Tian Zaobao Liu +3 位作者 Hongbo Li Enda Zhang Jinxin Zhou Jian-fu Shao 《Deep Resources Engineering》 2024年第3期57-81,共25页
Peridynamics(PD)is an emerging method that establishes a theoretical framework based on non-local theory to describe material mechanical behavior with spatial integral equations.It gives a unified expression of the me... Peridynamics(PD)is an emerging method that establishes a theoretical framework based on non-local theory to describe material mechanical behavior with spatial integral equations.It gives a unified expression of the me-dium including state transformation and characterization in different scales.It is showing great potential for evaluating the complicated mechanical behaviors of brittle solids.In the past two decades,peridynamics has been showing its great potential and advantages in modeling crackings of brittle materials although there are many challenges.The present paper summarizes firstly the theoretical framework and advantages of peridy-namics for modeling fracturing.It introduces then the theoretical improvements to address challenges of peri-dynamics in modeling brittle solid crackings including the release of Poisson ratio limit,different fracture criteria,contact-friction models,coupled constitutive models,and computing accuracy.Afterward,the extension of peridynamics is introduced to the coupled modeling with the other methods such as finite element method,phase field method,and particle-like method before its applications in static and dynamic cracking as well as those under impacts.Meanwhile,some contents that require further exploration are briefly summarized.Finally,the blind spots and future development of peridynamics are analyzed and discussed for the deformation and fracturing modeling of brittle geomaterials. 展开更多
关键词 PERIDYNAMICS Non-local theory Discontinuous problem Brittle geomaterials Numerical simulation
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Four cancer cases after esophageal atresia repair: Time to start screening the upper gastrointestinal tract 被引量:3
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作者 Floor WT Vergouwe Madeleine Gottrand +5 位作者 Bas PL Wijnhoven Hanneke IJsselstijn Guillaume Piessen Marco J Bruno René MH Wijnen Manon CW Spaander 《World Journal of Gastroenterology》 SCIE CAS 2018年第9期1056-1062,共7页
Esophageal atresia(EA) is one of the most common congenital digestive malformations and requires surgical correction early in life. Dedicated centers have reported survival rates up to 95%. The most frequent comorbidi... Esophageal atresia(EA) is one of the most common congenital digestive malformations and requires surgical correction early in life. Dedicated centers have reported survival rates up to 95%. The most frequent comorbidities after EA repair are dysphagia(72%) and gastroesophageal reflux(GER)(67%). Chronic GER after EA repair might lead to mucosal damage, esophageal stricturing, Barrett's esophagus and eventually esophageal adenocarcinoma. Several long-term follow-up studies found an increased risk of Barrett's esophagus and esophageal carcinoma in EA patients, both at a relatively young age. Given these findings, the recent ESPGHAN-NASPGHAN guideline recommends routine endoscopy in adults born with EA. We report a series of four EA patients who developed a carcinoma of the gastrointestinal tract: three esophageal carcinoma and one colorectal carcinoma in a colonic interposition. These cases emphasize the importance of lifelong screening of the upper gastrointestinal tract in EA patients. 展开更多
关键词 Adenocarcinoma ESOPHAGEAL ATRESIA ESOPHAGEAL CANCER SCREENING Barrett’s ESOPHAGUS SQUAMOUS cell carcinoma
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A novel approach for fabricating a CNT/AlSi composite with the self-aligned nacre-like architecture by cold spraying 被引量:4
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作者 Xinliang Xie Chaoyue Chen +5 位作者 Gang Ji Run Xu Zhanqiu Tan Yingchun Xie Zhiqiang Li Hanlin Liao 《Nano Materials Science》 CAS 2019年第2期137-141,共5页
A fully dense carbon nanotubes (CNTs) reinforced AlSi matrix composite with the multiscale nacre-like architecture was designed and successfully realized by flake powder metallurgy followed by cold spraying (CS). The ... A fully dense carbon nanotubes (CNTs) reinforced AlSi matrix composite with the multiscale nacre-like architecture was designed and successfully realized by flake powder metallurgy followed by cold spraying (CS). The nanolaminated and ultrafine-grained structure initially created in the CNT/AlSi flaky powder was perfectly conserved, due to the typical ‘cold’ feature of CS. As discussed based on finite element analysis and single splat observation, self-alignment behavior of the flaky powders during impact also allowed the formation of the microlaminated structure. Hence, the scalable CS technique opens a new avenue for bioinspired material design and fabrication with complex shape. 展开更多
关键词 ADDITIVE manufacturing Cold SPRAY Metal matrix composites Nanolaminated structure Carbon NANOTUBES
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中法老人基本心理需要满足对心理幸福感的影响:文化普遍性和差异性 被引量:6
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作者 汤岷岷 王大华 GUERRIEN Alain 《中国健康心理学杂志》 北大核心 2021年第3期327-333,共7页
目的:以自我决定理论为基础,并从跨文化的视角,来探讨中法两国老人的基本心理需要满足情况,及其对心理幸福感的影响。方法:对60~85岁的退休老人(n中=464,n法=129)施测基本心理需要满足量表,心理幸福感量表,主观健康和背景信息问卷。结果... 目的:以自我决定理论为基础,并从跨文化的视角,来探讨中法两国老人的基本心理需要满足情况,及其对心理幸福感的影响。方法:对60~85岁的退休老人(n中=464,n法=129)施测基本心理需要满足量表,心理幸福感量表,主观健康和背景信息问卷。结果:(1)3个基本心理需要满足(自主、能力和关系)均显著正向预测中法老人的心理幸福感;(2)法国老人的自主需要满足水平显著高于中国老人(t=-2.42,P<0.05),但其对心理幸福感的预测力并不存在差异;中国老人的能力需要满足(t=2.86,P<0.01)及其对心理幸福感的预测力显著高于法国老人(Z=2.33,P<0.05)。结论:基本心理需要满足对老年人心理幸福感的影响既有跨文化的普遍性,同时也表现出了东西方背景下的文化差异性。 展开更多
关键词 基本心理需要满足 心理幸福感 自我决定理论 跨文化 老年人
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Validating the CorrectWearing of Protection Mask by Taking a Selfie:Design of a Mobile Application“CheckYourMask”to Limit the Spread of COVID-19 被引量:2
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作者 Karim Hammoudi Adnane Cabani +1 位作者 Halim Benhabiles Mahmoud Melkemi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第9期1049-1059,共11页
In a context of a virus that is transmissive by sputtering,wearing masks appear necessary to protect the wearer and to limit the propagation of the disease.Currently,we are facing the 2019-2020 coronavirus pandemic.Co... In a context of a virus that is transmissive by sputtering,wearing masks appear necessary to protect the wearer and to limit the propagation of the disease.Currently,we are facing the 2019-2020 coronavirus pandemic.Coronavirus disease 2019(COVID-19)is an infectious disease with first symptoms similar to the flu.The symptom of COVID-19 was reported first in China and very quickly spreads to the rest of the world.The COVID-19 contagiousness is known to be high by comparison with the flu.In this paper,we propose a design of a mobile application for permitting everyone having a smartphone and being able to take a picture to verify that his/her protection mask is correctly positioned on his/her face.Such application can be particularly useful for people using face protection mask for the first time and notably for children and old people.The designed method exploits Haar-like feature descriptors to detect key features of the face and a decision-making algorithm is applied.Experimental results show the potential of this method in the validation of the correct mask wearing.To the best of our knowledge,our work is the only one that currently proposes a mobile application design“CheckYourMask”for validating the correct wearing of protection mask. 展开更多
关键词 Face protection masks public health support health education COVID-19 CORONAVIRUS E-HEALTH m-health mobile health public health system epidemic prevention and control
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Saccharomyces cerevisiae prevents postoperative recurrence of Crohn's disease modeled by ileocecal resection in HLA-B27 transgenic rats 被引量:2
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作者 Caroline Valibouze Silvia Speca +9 位作者 Caroline Dubuquoy Florian Mourey Lena M'Ba Lucil Schneider Marie Titecat Benoît Foligné Michaël Genin Christel Neut Philippe Zerbib Pierre Desreumaux 《World Journal of Gastroenterology》 SCIE CAS 2023年第5期851-866,共16页
BACKGROUND Postoperative recurrence(POR)after ileocecal resection(ICR)affects most Crohn's disease patients within 3-5 years after surgery.Adherent-invasive Escherichia coli(AIEC)typified by the LF82 strain are pa... BACKGROUND Postoperative recurrence(POR)after ileocecal resection(ICR)affects most Crohn's disease patients within 3-5 years after surgery.Adherent-invasive Escherichia coli(AIEC)typified by the LF82 strain are pathobionts that are frequently detected in POR of Crohn's disease and have a potential role in the early stages of the disease pathogenesis.Saccharomyces cerevisiae CNCM I-3856 is a probiotic yeast reported to inhibit AIEC adhesion to intestinal epithelial cells and to favor their elimination from the gut.AIM To evaluate the efficacy of CNCM I-3856 in preventing POR induced by LF82 in an HLA-B27 transgenic(TgB27)rat model.METHODS Sixty-four rats[strain F344,38 TgB27,26 control non-Tg(nTg)]underwent an ICR at the 12th wk(W12)of life and were sacrificed at the 18th wk(W18)of life.TgB27 rats were challenged daily with oral administration of LF82(109 colony forming units(CFUs)/day(d),n=8),PBS(n=5),CNCM I-3856(109 CFUs/d,n=7)or a combination of LF82 and CNCM I-3856(n=18).nTg rats receiving LF82(n=5),PBS(n=5),CNCM I-3856(n=7)or CNCM I-3856 and LF82(n=9)under the same conditions were used as controls.POR was analyzed using macroscopic(from 0 to 4)and histologic(from 0 to 6)scores.Luminal LF82 quantifications were performed weekly for each animal.Adherent LF82 and inflammatory/regulatory cytokines were quantified in biopsies at W12 and W18.Data are expressed as the median with the interquartile range.RESULTS nTg animals did not develop POR.A total of 7/8(87%)of the TgB27 rats receiving LF82 alone had POR(macroscopic score≥2),which was significantly prevented by CNCM I-3856 administration[6/18(33%)TgB27 rats,P=0.01].Macroscopic lesions were located 2 cm above the anastomosis in the TgB27 rats receiving LF82 alone and consisted of ulcerations with a score of 3.5(2-4).Seven out of 18 TgB27 rats(39%)receiving CNCM I-3856 and LF82 had no macroscopic lesions.Compared to untreated TgB27 animals receiving LF82 alone,coadministration of CNCM I-3856 and LF82 significantly reduced the macroscopic[3.5(2-4)vs 1(0-3),P=0.002]and histological lesions by more than 50%[4.5(3.3-5.8)vs 2(1.3-3),P=0.003].The levels of adherent LF82 were correlated with anastomotic macroscopic scores in TgB27 rats(r=0.49,P=0.006),with a higher risk of POR in animals having high levels of luminal LF82(71.4%vs 25%,P=0.02).Administration of CNCM I-3856 significantly reduced the levels of luminal and adherent LF82,increased the production of interleukin(IL)-10 and decreased the production of IL-23 and IL-17 in TgB27 rats.CONCLUSION In a reliable model of POR induced by LF82 in TgB27 rats,CNCM I-3856 prevents macroscopic POR by decreasing LF82 infection and gut inflammation. 展开更多
关键词 Crohn's disease RECURRENCE Escherichia coli Probiotic Saccharomyces cerevisiae Colorectal surgery
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Cue hierarchy in the foraging behaviour of the brackish cladoceran Daphniopsis australis 被引量:1
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作者 MCCLOUD Clayton Leigh ISMAIL Hasnun Nita SEURONT Laurent 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第6期2050-2060,共11页
Zooplankton communities are an essential component of marine and freshwater food webs. However, there is still a relative lack of information on how these organisms behaviourally respond to a range of abiotic and biot... Zooplankton communities are an essential component of marine and freshwater food webs. However, there is still a relative lack of information on how these organisms behaviourally respond to a range of abiotic and biotic stressors. Specifically, the behaviour of the cladoceran D aphniopsis australis, a species endemic to South-eastern Australian saline lakes and ponds, is still unknown despite its potential role in the structure and function of inland water ecosystems. The swimming behaviour of males, parthenogenetic females and epiphial females was investigated under various conditions and combinations of food and conspecific cues. In the absence of cues, males displayed the most extensive swimming behaviour, exploring all areas of the container, and swimming in a series of relatively straight trajectories. In contrast, females typically exhibited a hop-and-sink motion characterised by the alternation between short bursts of swimming and sinking phases. Both females spent long periods near the bottom of the container, but epiphial females appeared to be more active than parthenogenetic ones that rarely made an excursion in the water column. In the presence of cues, males and females showed abilities to detect infochemicals from food and conspecifics, but exhibited specific behavioural strategies. Males essentially increased their swimming speed in the presence of food and/or conspecific infochemicals, and this increase was independent on the source of the cues, i.e. food, conspecific or a mixture of food and conspecifics. In contrast, females exhibited cue hierarchies that were related to their sexual status. Parthenogenetic females swam faster in the presence of food and a mixture of food and conspecific infochemicals than in the presence of cue from the opposite sex, which did not significantly differ from control observations conducted in the absence of cues. Epiphial females decreased their swimming speed in the presence of cues, with the most significant behavioural answers being driven by sex-related cues. 展开更多
关键词 ZOOPLANKTON chemical cues SEX-SPECIFIC behaviour
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Effect of Zirconium and Cerium Loadings on Aerogel Pd-Based Catalysts for Methane Combustion 被引量:1
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作者 Khouloud Sadouki Shemseddine Fessi +3 位作者 Zouhaier Ksibi Mickael Capron Franck Dumeignil Abdelhamid Ghorbel 《Advances in Materials Physics and Chemistry》 2018年第3期105-119,共15页
Aerogel Pd/(Ce0.33Zr0.66O2)SiO2 catalysts (CeZry) were prepared with variable Ce and Zr loadings (molar ratio Ce/Zr = 1/2) by combining sol-gel and impregnation methods. First, N2-physisorption was used to investigate... Aerogel Pd/(Ce0.33Zr0.66O2)SiO2 catalysts (CeZry) were prepared with variable Ce and Zr loadings (molar ratio Ce/Zr = 1/2) by combining sol-gel and impregnation methods. First, N2-physisorption was used to investigate the texture evolution. Then, H2-chimisorption and TEM were performed to study the effect on particle dispersion. After, TPR was used to determine the catalyst reducibility. Furthermore, XPS characterization was done to identify the palladium oxidation state and to evaluate the Pd-support interaction. Finally, the prepared catalysts were tested in methane combustion to assess their catalytic activity. The obtained results showed that, when the Zr and Ce loadings are varied between 0% and 8% and between 0% and 6% respectively, the BET surface area was increased from 615 to 744 m2/g, the porosity diameter from 45.7 to 83.6 &#197;, the Pd particle diameter from 5.2 to 7.0 nm, the CeO2 and ZrO2 particle size from 0 to 68 nm, the reduction temperature shift reached 16°C, the Pd binding energy shift attained 0.6 eV, but an optimum amounts of Zr (4 wt.%) and Ce (3 wt.%) are needed to maximize the PdO reducibility and to enhance the catalytic activity. In effect, 100% conversion of methane was reached at around 415°C on the CeZr4 catalyst. 展开更多
关键词 Pd/(CexZr(1-x)O2)/SiO2 CATALYSTS Methane Combustion CATALYTIC Activity
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Performance comparison of chlorinated chiral stationary phases in supercritical fluid chromatography for separation of selected pyrrolidone derivatives
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作者 Anca-Elena Dascalu Alina Ghinet +1 位作者 Muriel Billamboz Emmanuelle Lipka 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2019年第4期248-253,共6页
The effects of two chlorinated chiral stationary phases, namely, Lux Cellulose-2 and Lux i-Cellulose-5, flow-rate, percentage of co-solvent and chemical structures of the compounds on retention and resolution were stu... The effects of two chlorinated chiral stationary phases, namely, Lux Cellulose-2 and Lux i-Cellulose-5, flow-rate, percentage of co-solvent and chemical structures of the compounds on retention and resolution were studied within this article. In this work a backpressure of 150 bar, a temperature of 40 ℃ and 10% of methanol as co-solvent were chosen as operating conditions. The optimum flow-rate was 2 mL/min. The percentage of co-solvent was studied between 7.5% and 15%.We have observed that 15% of methanol gave the best results for most of the compounds. For all the derivatives, the Lux Cellulose-2 provided better resolutions going from 1.50 to 3.59 compared with Lux i-Cellulose-5. 展开更多
关键词 ANTIBACTERIAL compounds CHIRALITY ENANTIOMERS FLOW-RATE Particle size
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Hinokiflavone and Related C-O-C-Type Biflavonoids as Anti-cancer Compounds:Properties and Mechanism of Action
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作者 Jean-François Goossens Laurence Goossens Christian Bailly 《Natural Products and Bioprospecting》 CAS 2021年第4期365-377,共13页
Biflavonoids are divided in two classes:C-C type compounds represented by the dimeric compound amentoflavone and C-O-C-type compounds typified by hinokiflavone(HNK)with an ether linkage between the two connected apige... Biflavonoids are divided in two classes:C-C type compounds represented by the dimeric compound amentoflavone and C-O-C-type compounds typified by hinokiflavone(HNK)with an ether linkage between the two connected apigenin units.This later sub-group of bisflavonyl ethers includes HNK,ochnaflavone,delicaflavone and a few other dimeric compounds,found in a variety of plants,notably Selaginella species.A comprehensive review of the anticancer properties and mechanism of action of HNK is provided,to highlight the anti-proliferative and anti-metastatic activities of HNK and derivatives,and HNK-containing plant extracts.The anticancer effects rely on the capacity of HNK to interfere with the ERK1-2/p38/NFκB signaling pathway and the regulation of the expression of the matrix metalloproteinases MMP-2 and MMP-9(with a potential direct binding to MMP-9).In addition,HNK was found to function as a potent modulator of pre-mRNA splicing,inhibit-ing the SUMO-specific protease SENP1.As such,HNK represents a rare SENP1 inhibitor of natural origin and a scaffold to design synthetic compounds.Oral formulations of HNK have been elaborated to enhance its solubility,to facilitate the compound delivery and to enhance its anticancer efficacy.The review shed light on the anticancer potential of C-O-C-type biflavonoids and specifically on the pharmacological profile of HNK.This compound deserves further attention as a regu-lator of pre-mRNA splicing,useful to treat cancers(in particular hepatocellular carcinoma)and other human pathologies. 展开更多
关键词 Hinokiflavone BIFLAVONOID Cancer therapy Mechanism of action Natural product
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Monitoring of pesticides residues in fruits and vegetables:Method optimization and application
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作者 Wissam Sahyoun Sopheak Net +1 位作者 Moomen Baroudi Baghdad Ouddane 《Food Bioscience》 SCIE 2022年第6期1812-1823,共12页
QuEChERS CEN Standard Method EN 15662 method was used with some modification for better efficiency of the extraction and purification of pesticides residues in fruits and vegetables matrix.The extracts were analyzed b... QuEChERS CEN Standard Method EN 15662 method was used with some modification for better efficiency of the extraction and purification of pesticides residues in fruits and vegetables matrix.The extracts were analyzed by GC–MS/MS for 14 multiclass pesticides in fruits and vegetables.The method was validated with real matrix with good efficiency ranging from 73 to 124%and the LODs and LOQs were 0.001–0.4μg kg−1 and 0.002–1.0μg kg−1 respectively.The method was applied to investigate the level of pesticide residues in 58 fruits and vegetables and with four condition:with and without washing,with and without skin.This condition is to simulate the condition how people consume fruits and vegetables and to find out if with the sample act,the level of pesticides can be reduced.This studied confirmed the absences or lower concentration of pesticides in organic fruits and vegetables compared to which originated from intensive agricultural where pesticides are widespread used.The results were then compared to the maximum residue limits for each pesticides and in each matrix.Our results allow to conclude that washing or removing skin should be one of the solution to reduced health impact related to pesticide in fruits and vegetables. 展开更多
关键词 d-SPE QuEChERS extraction GC-MS/MS PESTICIDES FRUITS VEGETABLES
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OTX2 signaling in retinal dysfunction,degeneration and regeneration
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作者 Kenneth.L.Moya Raoul Torero Ibad 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第10期2002-2003,共2页
The protein OTX2 in the retina is necessary for the maintenance of normal physiologic processes,and may be a promising therapeutic agent for some ophthalmic diseases.In this Perspective,we first shortly introduce the ... The protein OTX2 in the retina is necessary for the maintenance of normal physiologic processes,and may be a promising therapeutic agent for some ophthalmic diseases.In this Perspective,we first shortly introduce the organization of the retina and the importance of OTX2 expression.We then present an example of reduced OTX2 activity in the developed retina associated with structural and functional consequences.We next show that homeoproteins can have neuroprotective functions.We finally review several clear examples of OTX2 non-cell autonomous activity in the retina and the effects of diminishing or providing extracellular OTX2. 展开更多
关键词 expression. functions. agent
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An explicit formulation of the macroscopic strength criterion for porous media with pressure and Lode angle dependent matrix under axisymmetric loading
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作者 Jincheng Fan Laurence Brassart +1 位作者 Wanqing Shen Xiurun Ge 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第4期820-832,共13页
This paper aims to propose an explicit formulation of the macroscopic strength criterion for porous media with spherical voids.The matrix is assumed rigid and perfectly plastic with yield surface described by the thre... This paper aims to propose an explicit formulation of the macroscopic strength criterion for porous media with spherical voids.The matrix is assumed rigid and perfectly plastic with yield surface described by the three-parameter strength criterion,which is Lode angle and pressure dependent and capable of accounting for distinct values of the uniaxial tensile strength,uniaxial compressive strength(UCS)and equal biaxial compressive strength(eBCS).An exact upper bound of the macroscopic strength is derived for porous media subjected to purely hydrostatic loading.Besides,an estimate of the macroscopic strength profile of porous media under axisymmetric loading is obtained in parametric form.Moreover,a heuristic strength criterion in explicit form is further developed by examining limit cases of the parametric strength criterion.The developed strength criteria are assessed by finite-element based numerical solutions.Compared with the parametric strength criterion which involves cumbersome functions,the heuristic one is convenient for practical applications.For specific values of the matrix’s strength surface,the proposed heuristic strength criterion can recover the well-known Gurson criterion.The present work also addresses the effect of the ratio of matrix’s eBCS to UCS on the macroscopic strength of porous media.For matrix with distinct values of eBCS and UCS,neglecting the difference between eBCS and UCS would result in an underestimation of the macroscopic strength,especially when the pressure is large. 展开更多
关键词 Porous materials Unified strength criterion HOMOGENIZATION Gurson criterion
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In silico assessment of human health risks caused by cyanotoxins from cyanobacteria
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作者 JIA-FONG HONG BAGHDAD OUDDANE +1 位作者 JIANG-SHIOU HWANG HANS-UWE DAHMS 《BIOCELL》 SCIE 2021年第1期65-77,共13页
Harmful algal blooms(HABs)that are formed by cyanobacteria have become a serious issue worldwide in recent years.Cyanobacteria can release a type of secondary metabolites called cyanotoxins into aquatic systems which ... Harmful algal blooms(HABs)that are formed by cyanobacteria have become a serious issue worldwide in recent years.Cyanobacteria can release a type of secondary metabolites called cyanotoxins into aquatic systems which may indirectly or directly provide health risks to the environment and humans.Cyanotoxins provide some of the most powerful natural poisons including potent neurotoxins,hepatotoxins,cytotoxins,and endotoxins that may result in environmental health risks,and long-term morbidity and mortality to animals and humans.In this research,we used the chemcomputational tool Molinspiration for molecular property predictions,Pred-hERG 4.2 web software for cardiac toxicity prediction,and Pred-Skin 2.0 web software for predicting skin sensitization.We are predicting some toxicological aspects of cyanobacteria here using chemcomputational tools with the hypothesis that cyanotoxins are providing a risk to human health.We are using the tool Pred-hERG 4.2 to predict hERG channel blocking potential and the Pred-skin tool to predict skin sensitization due to cyanotoxins.The potential of anatoxin,ambigol,the microcystin group,and lyngbyatoxin A,lyngbyatoxin B,nodularin-R,and saxitoxin were predicted to cause skin sensitization in the final results(consensus model).Anatoxin-a and lyngbyatoxin were predicted to allow GI absorption and blood–brain barrier penetration.Among the 20 predicted cyanotoxins only aeruginosin 103-A,ambigol A,and ambigol were predicted by Pred-hERG 4.2 according to the applicability domain results as potential cardiotoxins with weak or moderate potency.Lyngbyatoxin shows activity through the GPCR ligand and protease,kinase,and enzyme inhibitor. 展开更多
关键词 CYANOTOXINS Predictive model Molinspiration Bioactivity score hERG blocker CARCINOGENICITY
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Genome analyses of Weissella strains isolated from Campos das Vertentes, Minas Gerais, Brazil revealed new bacteriocins with a large spectrum of activity
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作者 Camila Goncalves Teixeira Rafaela da Silva Rodrigues +3 位作者 Anca Lucau-Danila Luis Augusto Nero Antonio Fernandes de Carvalho Djamel Drider 《Food Bioscience》 SCIE 2023年第2期616-621,共6页
This work aimed at characterizing the Weissella cibaria strains isolated from Campos das Vertentes,Minas Gerais,Brazil and their antimicrobial potential.Thus,three strains of W.cibaria(W21,W25 and W42)were previously ... This work aimed at characterizing the Weissella cibaria strains isolated from Campos das Vertentes,Minas Gerais,Brazil and their antimicrobial potential.Thus,three strains of W.cibaria(W21,W25 and W42)were previously selected,and the genomes of W21 and W42 were sequenced,while that of strain W25 was already sequenced and reported.Afterwhich,we investigated the presence of genes coding for potential secondary metabolites in the genomes of the strains using the AntiSmash webtool,and located a common region coding for a putative bacteriocin identified as Bacteriocin_IIc.Then,we assessed in vitro this antimicrobial activity using the supernatant of these strains.According to the data,the strain W21,which has one transport-related gene missing from the bacteriocin operon compared to W25 and W42,likewise showed no differences in the in vitro antimicrobial test when comparing the outcomes of the three treatments(supernatant without treatment,neutralized and treated with proteinase K).Also,we compared the nucleotides and amino acids of this putative bacteriocin in the NCBI platform and there was no similarity with other so far described bacteriocin from the genus Weissella.In conclusion,two of the three Weissella strains tested in this work have the potential to produce a new bacteriocin not yet described which needs to be deeply characterized and proposed for food protection as alternatives to chemicals in foods. 展开更多
关键词 Weissella cibaria BACTERIOCINS Antimicrobial activity
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