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Interface optimization and defects suppression via Na F introduction enable efficient flexible Sb_(2)Se_(3) thin-film solar cells
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作者 Mingdong Chen Muhammad Ishaq +7 位作者 Donglou Ren Hongli Ma Zhenghua Su Ping Fan David Le Coq Xianghua Zhang Guangxing Liang Shuo Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期165-175,I0006,共12页
Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible devices.However,the power conversion efficiency(PCE) of f... Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible devices.However,the power conversion efficiency(PCE) of flexible Sb_(2)Se_(3) photovoltaic devices is temporarily limited by the complicated intrinsic defects and the undesirable contact interfaces.Herein,a high-quality Sb_(2)Se_(3) absorber layer with large crystal grains and benign [hkl] growth orientation can be first prepared on a Mo foil substrate.Then NaF intermediate layer is introduced between Mo and Sb_(2)Se_(3),which can further optimize the growth of Sb_(2)Se_(3)thin film.Moreover,positive Na ion diffusion enables it to dramatically lower barrier height at the back contact interface and passivate harmful defects at both bulk and heterojunction.As a result,the champion substrate structured Mo-foil/Mo/NaF/Sb_(2)Se_(3)/CdS/ITO/Ag flexible thin-film solar cell delivers an obviously higher efficiency of 8.03% and a record open-circuit voltage(V_(OC)) of 0.492 V.This flexible Sb_(2)Se_(3) device also exhibits excellent stability and flexibility to stand large bending radius and multiple bending times,as well as superior weak light photo-response with derived efficiency of 12.60%.This work presents an effective strategy to enhance the flexible Sb_(2)Se_(3) device performance and expand its potential photovoltaic applications. 展开更多
关键词 Sb_(2)Se_(3) Flexible solar cells NaF intermediate layer Interface optimization Defects suppression
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Late Mesozoic Exhumation of the Huangling Massif:Constraints on the Evolution of the Middle Yangtze River
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作者 SU Jianchao LIN Xu +7 位作者 LI Chang’an Jolivet MARC WU Lin CHENG Feng DENG Bin WU Zhonghai CHEN Xiaokang HU Chengwei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期250-264,共15页
Plate subduction leads to complex exhumation processes on continents.The Huangling Massif lies at the northern margin of the South China Block.Whether the Huangling Massif was exhumed as a watershed of the middle reac... Plate subduction leads to complex exhumation processes on continents.The Huangling Massif lies at the northern margin of the South China Block.Whether the Huangling Massif was exhumed as a watershed of the middle reaches of the Paleo-Yangtze River during the Mesozoic remains under debate.We examined the exhumation history of the Huangling Massif based on six granite bedrock samples,using apatite fission track(AFT)and apatite and zircon(U-Th)/He(AHe and ZHe)thermochronology.These samples yielded ages of 157–132 Ma(ZHe),119–106 Ma(AFT),and 114–72 Ma(AHe),respectively.Thermal modeling revealed that three phases of rapid cooling occurred during the Late Jurassic–Early Cretaceous,late Early Cretaceous,and Late Cretaceous.These exhumation processes led to the high topographic relief responsible for the emergence of the Huangling Massif.The integrated of our new data with published sedimentological records suggests that the Huangling Massif might have been the watershed of the middle reaches of the Paleo-Yangtze River since the Cretaceous.At that time,the rivers flowed westward into the Sichuan Basin and eastward into the Jianghan Basin.The subduction of the Pacific Plate beneath the Asian continent in the Mesozoic deeply influenced the geomorphic evolution of the South China Block. 展开更多
关键词 APATITE ZIRCON (U-Th)/He fission track Huangling Massif Yangtze River
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Electrochemical Study of the Corrosion Inhibitory Capacity of Calcined Attapulgite in Reinforced Concrete Medium
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作者 Malang Bodian Kinda Hannawi +3 位作者 Dame Keinde Modou Fall Aveline Darquennes Prince William Agbodjan 《Advances in Materials Physics and Chemistry》 CAS 2024年第5期76-94,共19页
The durability of reinforced concrete structures is greatly influenced by the corrosion of the reinforcement. In addition to air pollution related to the repair of corroded structures, chloride ions are the main facto... The durability of reinforced concrete structures is greatly influenced by the corrosion of the reinforcement. In addition to air pollution related to the repair of corroded structures, chloride ions are the main factors of corrosion of reinforced concrete structures. This study aims to valorize a clay inhibitor against reinforcement corrosion in reinforced concrete. This clay (Attapulgite) was incorporated into reinforced concretes at different percentages of substitution of calcined attapulgite (0%, 5% and 10%) to cement in the formulation. The corrosion inhibitory power of attapulgite is evaluated in reinforced concretes subjected to the action of chloride ions at different intervals in the NaCl solution (1 day, 21 days and 45 days) by electrochemical methods (zero current chronopotentiometry, polarization curves and electrochemical impedance spectroscopy). This study showed that in the presence of chloride ions, the composition based on 10% attapulgite has an appreciable inhibitory effect with an average inhibitory efficiency of 82%. 展开更多
关键词 ATTAPULGITE Electrochemical Methods INHIBITOR Reinforced Concrete
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Epidemiology, Clinical Features and Antifungal Resistance Profile of Candida auris in Africa: Systematic Review
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作者 Isidore Wendkièta Yerbanga Seydou Nakanabo Diallo +8 位作者 Toussaint Rouamba Delwendé Florence Ouedraogo Katrien Lagrou Rita Oladele Jean-Pierre Gangneux Olivier Denis Hector Rodriguez-Villalobos Isabel Montesinos Sanata Bamba 《Journal of Biosciences and Medicines》 2024年第1期126-149,共24页
Candida auris since it discovery in 2009 is becoming a severe threat to human health due to its very quickly spread, its worldwide high resistance to systemic antifungal drugs. In resource-constrained settings where s... Candida auris since it discovery in 2009 is becoming a severe threat to human health due to its very quickly spread, its worldwide high resistance to systemic antifungal drugs. In resource-constrained settings where several conditions are met for its emergence and spread, this worrisome fungus could cause large hospital and/or community-based outbreaks. This review aimed to summarize the available data on C. auris in Africa focusing on its epidemiology and antifungal resistance profile. Major databases were searched for articles on the epidemiology and antifungal resistance profile of C. auris in Africa. Out of 2,521 articles identified 22 met the inclusion criteria. In Africa, nearly 89% of African countries have no published data on C. auris. The prevalence of C. auris in Africa was 8.74%. The case fatality rate of C. auris infection in Africa was 39.46%. The main C. auris risk factors reported in Africa were cardiovascular disease, renal failure, diabetes, HIV, recent intake of antimicrobial drugs, ICU admissions, surgery, hemodialysis, parenteral nutrition and indwelling devices. Four phylogenetic clades were reported in Africa, namely clades I, II, III and IV. Candida auris showed a pan-African very high resistance rate to fluconazole, moderate resistance to amphotericin B, and high susceptibility to echinocandins. Finally, C. auris clade-specific mutations were observed within the ERG2, ERG3, ERG9, ERG11, FKS1, TAC1b and MRR1 genes in Africa. This systematic review showed the presence of C. auris in the African continent and a worrying unavailability of data on this resilient fungus in most African countries. 展开更多
关键词 AFRICA Antifungal Resistance Candida auris Clinical Features Phylogenetic Clades
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Evaluation of the Inhibitory Gel Aloe vera against Corrosion of Reinforcement Concrete in NaCl Medium
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作者 Malang Bodian Dame Keinde +3 位作者 Kinda Hannawi Modou Fall Aveline Darquennes Prince William Agbodjan 《Materials Sciences and Applications》 2024年第5期101-112,共12页
Most reinforced concrete structures in seaside locations suffer from corrosion damage to the reinforcement, limiting their durability and necessitating costly repairs. To improve their performance and durability, we h... Most reinforced concrete structures in seaside locations suffer from corrosion damage to the reinforcement, limiting their durability and necessitating costly repairs. To improve their performance and durability, we have investigated in this paper Aloe vera extracts as a green corrosion inhibitor for reinforcing steel in NaCl environments. Using electrochemical methods (zero-intensity chronopotentiometry, Tafel lines and electrochemical impedance spectroscopy), this experimental work investigated the effect of these Aloe vera (AV) extracts on corrosion inhibition of concrete reinforcing bar (HA, diameter 12mm) immersed in a 0.5M NaCl solution. The results show that Aloe vera extracts have an average corrosion-inhibiting efficacy of around 86% at an optimum concentration of 20%. 展开更多
关键词 Reinforced Concrete Green Inhibitor Corrosion REINFORCEMENT Electrochemical Methods
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The sperm-interacting proteome in the bovine isthmus and ampulla during the periovulatory period
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作者 Coline Mahe Regis Lavigne +6 位作者 Emmanuelle Com Charles Pineau Aleksandra Maria Zlotkowska Guillaume Tsikis Pascal Mermillod Jennifer Schoen Marie Saint-Dizier 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期980-1000,共21页
Background Spermatozoa interact with oviduct secretions before fertilization in vivo but the molecular players of this dialog and underlying dynamics remain largely unknown.Our objectives were to identify an exhaustiv... Background Spermatozoa interact with oviduct secretions before fertilization in vivo but the molecular players of this dialog and underlying dynamics remain largely unknown.Our objectives were to identify an exhaustive list of sperm-interacting proteins(SIPs)in the bovine oviduct fluid and to evaluate the impact of the oviduct anatomical region(isthmus vs.ampulla)and time relative to ovulation(pre-ovulatory vs.post-ovulatory)on SIPs number and abundance.Methods Pools of oviduct fluid(OF)from the pre-ovulatory ampulla,pre-ovulatory isthmus,post-ovulatory ampulla,and post-ovulatory isthmus in the side of ovulation were collected from the slaughterhouse.Frozen-thawed bull sperm were incubated with OF or phosphate-buffered saline(control)for 60 min at 38.5℃.After protein extraction and digestion,sperm and OF samples were analyzed by nanoLC-MS/MS and label-free protein quantification.Results A quantitative comparison between proteins identified in sperm and OF samples(2333 and 2471 proteins,respectively)allowed for the identification of 245 SIPs.The highest number(187)were found in the pre-ovulatory isthmus,i.e.,time and place of the sperm reservoir.In total,41 SIPs(17%)were differentially abundant between stages in a given region or between regions at a given stage and 76 SIPs(31%)were identified in only one region×stage condition.Functional analysis of SIPs predicted roles in cell response to stress,regulation of cell motility,fertilization,and early embryo development.Conclusion This study provides a comprehensive list of SIPs in the bovine oviduct and evidences dynamic spatiotemporal changes in sperm-oviduct interactions around ovulation time.Moreover,these data provide protein candidates to improve sperm conservation and in vitro fertilization media. 展开更多
关键词 AMPULLA Fallopian tube INTERACTOME ISTHMUS OVIDUCT OVULATION Post-ovulatory Pre-ovulatory Proteomics SPERMATOZOA
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Specific alterations of regional myocardial work in strength-trained athletes using anabolic androgenic steroids compared to athletes with genetic hypertrophic cardiomyopathy
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作者 Antoine Grandperrin Frédéric Schnell +4 位作者 Erwan Donal Elena Galli Christophe Hedon Olivier Cazorla Stéphane Nottin 《Journal of Sport and Health Science》 SCIE CAS CSCD 2023年第4期477-485,共9页
Background:Strength-trained athletes using anabolic androgenic steroids(AAS)have left ventricular(LV)hypertrophy and myocardial fibrosis that can lead to sudden cardiac death.A similar feature was described in athlete... Background:Strength-trained athletes using anabolic androgenic steroids(AAS)have left ventricular(LV)hypertrophy and myocardial fibrosis that can lead to sudden cardiac death.A similar feature was described in athletes with hypertrophic cardiomyopathy(HCM),which complicates the diagnosis for clinicians.In this context,we aimed to compare the LV function of the 2 populations by measuring global and regional strain and myocardial work using speckle-tracking imaging.Methods:Twenty-four strength-trained asymptomatic athletes using AAS(AAS-Athletes),22 athletes diagnosed with HCM(HCM-Athletes),and 20 healthy control athletes(Ctrl-Athletes)underwent a resting echocardiography to assess LV function.We evaluated LV global and regional strains and myocardial work,with an evaluation of the constructive work(CW),wasted work,and work efficiency(WE).Results:Compared to Ctrl-Athletes,both AAS-Athletes and HCM-Athletes had a thicker interventricular septum,with maj ored values in HCM-Athletes.LV strain was reduced in AAS-Athletes and even more in HCM-Athletes.Consequently,global WE was significantly diminished in both AAS and HCM-Athletes(93%±2%in Ctrl-Athletes,90%±4%in AAS-Athletes,and 90%±5%in HCM-Athletes(mean±SD);p<0.05).Constructive work and WE regional analysis showed specific alterations,with the basal septal segments preferentially affected in AAS-Athletes,and both septal and apical segments affected in HCM-Athletes.Conclusion:The regional evaluation of myocardial work reported specific alterations of the major LV hypertrophy induced by the regular use of AAS compared to the LV hypertrophy due to HCM.This finding could help clinicians to differentiate between these 2 forms of pathological hypertrophy. 展开更多
关键词 Anabolic androgenic steroids Hypertrophic cardiomyopathy Left ventricular function Myocardial work Speckle-tracking echocardiography
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Back contact interfacial modification mechanism in highly-efficient antimony selenide thin-film solar cells
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作者 Junhui Lin Guojie Chen +7 位作者 Nafees Ahmad Muhammad Ishaq Shuo Chen Zhenghua Su Ping Fan Xianghua Zhang Yi Zhang Guangxing Liang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期256-264,I0007,共10页
Antimony selenide(Sb_(2)Se_(3))is a potential photovoltaic(PV)material for next-generation solar cells and has achieved great development in the last several years.The properties of Sb_(2)Se_(3)absorber and back conta... Antimony selenide(Sb_(2)Se_(3))is a potential photovoltaic(PV)material for next-generation solar cells and has achieved great development in the last several years.The properties of Sb_(2)Se_(3)absorber and back contact influence the PV performances of Sb_(2)Se_(3)solar cells.Hence,optimization of back contact characteristics and absorber orientation are crucial steps in raising the power conversion efficiency(PCE)of Sb_(2)Se_(3)solar cells.In this work,MoO2was introduced as an intermediate layer(IL)in Sb_(2)Se_(3)solar cells,and comparative investigations were conducted.The growth of(211)-oriented Sb_(2)Se_(3)with large grains was facilitated by introducing the MoO2IL with suitable thickness.The MoO2IL substantially lowered the back contact barrier and prevented the formation of voids at the back contact,which reduced the thickness of the MoSe2interface layer,inhibited carrier recombination,and minimized bulk and interfacial defects in devices.Subsequently,significant optimization enhanced the open-circuit voltage(VOC)of solar cells from 0.481 V to 0.487 V,short-circuit current density(JSC)from 23.81 m A/cm^(2)to 29.29 m A/cm^(2),and fill factor from 50.28%to 57.10%,which boosted the PCE from 5.75%to 8.14%. 展开更多
关键词 Sb_(2)Se_(3)solar cells MoO_(2)intermediate layer Back contact DEFECTS
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Bending and Free Vibration Analysis of Porous-Functionally-Graded(PFG)Beams Resting on Elastic Foundations
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作者 Lazreg Hadji Fabrice Bernard Nafissa Zouatnia 《Fluid Dynamics & Materials Processing》 EI 2023年第4期1043-1054,共12页
The bending and free vibration of porous functionally graded(PFG)beams resting on elastic foundations are analyzed.The material features of the PFG beam are assumed to vary continuously through the thickness according... The bending and free vibration of porous functionally graded(PFG)beams resting on elastic foundations are analyzed.The material features of the PFG beam are assumed to vary continuously through the thickness according to the volume fraction of components.The foundation medium is also considered to be linear,homogeneous,and isotropic,and modeled using the Winkler-Pasternak law.The hyperbolic shear deformation theory is applied for the kinematic relations,and the equations of motion are obtained using the Hamilton’s principle.An analytical solution is presented accordingly,assuming that the PFG beam is simply supported.Comparisons with the open literature are implemented to verify the validity of such a formulation.The effects of the elastic foundations,porosity volume percentage and span-to-depth ratio are finally discussed in detail. 展开更多
关键词 BENDING free vibration porosity functionally graded material winkler-pasternak elastic foundation
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Guest Editorial:Special issue on intelligence technology for remote sensing image
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作者 Xiangtao Zheng Benoit Vozel Danfeng Hong 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1164-1165,共2页
With the development of artificial intelligence,remote sensing scene interpretation task has attracted extensive attention,which mainly includes scene classification,target detection,hyperspectral classification,and m... With the development of artificial intelligence,remote sensing scene interpretation task has attracted extensive attention,which mainly includes scene classification,target detection,hyperspectral classification,and multi‐modal analysis.The remote sensing scene interpretation has effectively promoted the development of the Earth observation field.It was the intention for this Special Issue to serve as a platform for the publication of the most recent research concepts from remote sensing image. 展开更多
关键词 artificial analysis. IMAGE
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Association between ACTN3 R577X genotype and risk of non-contact injury in trained athletes:A systematic review
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作者 Hassane Zouhal Juan Del Coso +7 位作者 Ayyappan Jayavel Claire Toumy Guillaume Ravé Nidhal Jebabli Cain C.T.Clark Benjamin Barthélémy Anthony C.Hackney Abderraouf Ben Abderrahman 《Journal of Sport and Health Science》 SCIE CSCD 2023年第3期359-368,共10页
Purpose:The aim of this study was to review,systematically,evidence concerning the link between the ACTN3 R577X polymorphism and the rates and severity of non-contact injuries and exercise-induced muscle damage in ath... Purpose:The aim of this study was to review,systematically,evidence concerning the link between the ACTN3 R577X polymorphism and the rates and severity of non-contact injuries and exercise-induced muscle damage in athletes and individuals enrolled in exercise training programs.Methods:A computerized literature search was performed in the electronic databases PubMed,Web of Science,and SPORTDiscus,from inception until November 2020.All included studies compared the epidemiological characteristics of non-contact injury between the different genotypes of the ACTN3 R577X polymorphism.Results:Our search identified 492 records.After the screening of titles,abstracts,and full texts,13 studies examining the association between the ACTN3 genotypes and the rate and severity of non-contact injury were included in the analysis.These studies were performed in 6 different countries(Spain,Japan,Brazil,China,the Republic of Korea,and Italy)and involved a total participant pool of 1093 participants.Of the studies,2 studies involved only women,5 studies involved only men,and 6 studies involved both men and women.All the studies included were classified as highquality studies(≥6 points in the Physiotherapy Evidence Database(PEDro)scale score).Overall,evidence suggests there is an association between the ACTN3 R577X genotype and non-contact injury in 12 investigations.Six studies observed a significant association between A CTN3 R577X polymorphism and exercise induced muscle damage:2 with non-contact ankle injury,3 with non-contact muscle injury,and 1 with overall non-contact injury.Conclusion:The present findings support the premise that possessing the ACTN3 XX genotype may predispose athletes to a higher probability of some non-contact injuries,such as muscle injury,ankle sprains,and higher levels of exercise-induced muscle damage. 展开更多
关键词 α-actinin-3 deficiency Athletic performance Exercise-related injury Muscle injury Single nucleotide polymorphism
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Modeling and Analysis of UAV-Assisted Mobile Network with Imperfect Beam Alignment
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作者 Mohamed Amine Ouamri Reem Alkanhel +2 位作者 Cedric Gueguen Manal Abdullah Alohali Sherif S.M.Ghoneim 《Computers, Materials & Continua》 SCIE EI 2023年第1期453-467,共15页
With the rapid development of emerging 5G and beyond(B5G),Unmanned Aerial Vehicles(UAVs)are increasingly important to improve the performance of dense cellular networks.As a conventional metric,coverage probability ha... With the rapid development of emerging 5G and beyond(B5G),Unmanned Aerial Vehicles(UAVs)are increasingly important to improve the performance of dense cellular networks.As a conventional metric,coverage probability has been widely studied in communication systems due to the increasing density of users and complexity of the heterogeneous environment.In recent years,stochastic geometry has attracted more attention as a mathematical tool for modeling mobile network systems.In this paper,an analytical approach to the coverage probability analysis of UAV-assisted cellular networks with imperfect beam alignment has been proposed.An assumption was considered that all users are distributed according to Poisson Cluster Process(PCP)around base stations,in particular,Thomas Cluster Process(TCP).Using thismodel,the impact of beam alignment errors on the coverage probabilitywas investigated.Initially,the ProbabilityDensity Function(PDF)of directional antenna gain between the user and its serving base station was obtained.Then,association probability with each tier was achieved.A tractable expression was derived for coverage probability in both Line-of-Sight(LoS)andNon-Line-of-Sight(NLoS)condition links.Numerical results demonstrated that at low UAVs altitude,beam alignment errors significantly degrade coverage performance.Moreover,for a small cluster size,alignment errors do not necessarily affect the coverage performance. 展开更多
关键词 Unmanned aerial vehicles coverage analysis stochastic geometry millimeter wave imperfect beam alignment
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Screening for Precancerous Cervical Lesions in Women of Reproductive Age in the Kara Region of Togo in 2022
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作者 Gatibe Yendu-Suglpak Gnatou Zézé Onivogui +7 位作者 Latame Komla Adoli Fifonsi Adjidossi Gbeasor-Komlanvi Arnold Junior Sadio Yao Rodion Konu Martin Kouame Tchankoni Wendpouiré Ida Carine Zida-Compaore Amegnona Agbonon Didier Koumavi Ekouevi 《Open Journal of Epidemiology》 2023年第4期293-305,共13页
Introduction: Worldwide, cervical cancer is the 4<sup>th</sup> most common cancer in women and is a public health problem. The objective of this study was to estimate the prevalence of precancerous cervica... Introduction: Worldwide, cervical cancer is the 4<sup>th</sup> most common cancer in women and is a public health problem. The objective of this study was to estimate the prevalence of precancerous cervical lesions and to describe its associated factors among women of reproductive age in the Kara region of Togo. Methods: A cross-sectional study was conducted from March 6 to 14, 2022 in 11 health centers in Kara. Data were collected using a standardized questionnaire and screening for precancerous cervical lesions was performed by visual inspection of the cervix, after application of 5% acetic acid and Lugol’s. Logistic regression analysis was performed to describe factors associated with precancerous lesions. Results: A total of 728 women with a median age of 36, interquartile range [31 - 41] were enrolled. The prevalence of precancerous cervical lesions was 3.9%, 95% confidence interval (95% CI: [2.6 - 5.4]. Factors associated with the presence of precancerous lesions were age at first sexual intercourse ≥ 18 years (adjusted odds ratio (aOR = 3.67;95% CI [1.17 - 18.4]) and being a sex worker (aOR = 8.14;95% CI [1.96 - 27.1]). HIV infection was not associated with the presence of precancerous lesions. Conclusion: The results of this study underscore the importance of intensifying cervical cancer screening efforts in resource-limited countries for better management. These efforts should prioritize vulnerable populations such as female sex workers. 展开更多
关键词 Precancerous Lesions CERVIX Visual Inspection TOGO
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Effect of Changing Anion on the Crystalline Structure, Crystal Structure, Hirschfield Surface, IR and NMR Spectroscopy of Organic Salts and Hybrid Compounds: C6H4(NH3)2Cl2 (I), β-[C6H10N2]2ZnCl4 (II), Respectively
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作者 Nejeh Hannachi Rim Elwej +1 位作者 Thierry Roisnel Faouzi Hlel 《Open Journal of Inorganic Chemistry》 CAS 2023年第1期1-24,共24页
Two organic-inorganic hybrid materials, C<sub>6</sub>H<sub>4</sub>(NH<sub>3</sub>)<sub>2</sub>∙Cl<sub>2</sub> (I) and β-[C<sub>6</sub>H<sub&g... Two organic-inorganic hybrid materials, C<sub>6</sub>H<sub>4</sub>(NH<sub>3</sub>)<sub>2</sub>∙Cl<sub>2</sub> (I) and β-[C<sub>6</sub>H<sub>10</sub>N<sub>2</sub>]<sub>2</sub>ZnCl<sub>4</sub> (II), have been synthesized by hydrothermal method. These two materials are one of the hybrid materials have emerged as one of the most brilliant components classes. These extraordinary compounds synergistically combine the desired physical properties of both organic and inorganic components into a single compound offering the possibility to achieve great improvement over time in terms of science across various sectors. Their structures were determined by XRD pattern investigations and single crystal X-ray diffraction. These two compounds are crystallized in the monoclinic system;C2/c space group. In the both structures, the anionic-cationic entities are interconnected by hydrogen bonding contacts and p-p Interaction forming three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces and the contacts of the four different chloride atoms in (II) were compared. The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid state<sup>13</sup>C NMR spectroscopy. 展开更多
关键词 Crystal Structure Hirshfeld Surface 13C NMR-MAS Vibration Absorption
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远红外Ge-Te-Ⅰ高卤硫系玻璃的制备及其光学性能的研究 被引量:7
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作者 程辞 王训四 +9 位作者 徐铁峰 朱敏鸣 姜晨 祝清德 廖方兴 聂秋华 戴世勋 沈祥 张培全 章向华 《光子学报》 EI CAS CSCD 北大核心 2015年第2期100-105,共6页
为获得高质量的远红外硫系玻璃,采用传统的真空熔融淬冷法配合真空低温固化技术制备了高卤素含量的Te硫系玻璃(卤素Imax=40at.%),并分析了该系列Ge20Te80-xIx(x=10、15、20、25、30、35、40)硫卤玻璃样品.采用分光光度计和傅里叶红外光... 为获得高质量的远红外硫系玻璃,采用传统的真空熔融淬冷法配合真空低温固化技术制备了高卤素含量的Te硫系玻璃(卤素Imax=40at.%),并分析了该系列Ge20Te80-xIx(x=10、15、20、25、30、35、40)硫卤玻璃样品.采用分光光度计和傅里叶红外光谱仪等光学仪器分析该玻璃的可见/近红外吸收光谱和红外透射光谱等频谱性质,利用Raman光谱仪和X射线衍射仪分析了玻璃的内部微观结构.研究表明,随着卤素I元素的增加,可见/近红外吸收光谱的短波截止边持续发生蓝移,光学带隙持续增大,从近红外的1μm一直到远红外波长25μm都保持透光性;Ge20Te65I15玻璃的转变温度最大,在138℃附近,其红外透过率最高,达到50%. 展开更多
关键词 Te基硫卤玻璃 红外透过 蓝移 光学带隙 吸收光谱
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蓝绿光上转换荧光输出的稀土掺杂玻璃研究进展 被引量:10
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作者 聂秋华 金哲 +3 位作者 徐铁峰 戴世勋 沈祥 章向华 《硅酸盐通报》 CAS CSCD 北大核心 2006年第5期108-117,共10页
上转换光纤激光器由于在医疗、生命科学等领域应用逐步加强,近年来受到了广泛的重视。本文简要回顾了上转换发光的发展历程,归纳了能够实现蓝绿光输出的稀土离子的种类,详细阐述了近年来具有蓝绿光输出的上转换发光的不同基质玻璃(氟化... 上转换光纤激光器由于在医疗、生命科学等领域应用逐步加强,近年来受到了广泛的重视。本文简要回顾了上转换发光的发展历程,归纳了能够实现蓝绿光输出的稀土离子的种类,详细阐述了近年来具有蓝绿光输出的上转换发光的不同基质玻璃(氟化物玻璃、硫化物玻璃、碲酸盐玻璃、锗酸盐玻璃、铋酸盐玻璃、卤氧化物玻璃)的研究进展,最后,对稀土离子掺杂的玻璃上转换发光的研究动向进行了展望。 展开更多
关键词 稀土离子 上转换 玻璃基质 研究进展
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一株抗氧化活性酵母菌产多糖的纯化与结构分析 被引量:7
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作者 陈历水 马莺 +1 位作者 刘天一 Jean-Louis Maubois 《分析化学》 SCIE EI CAS CSCD 北大核心 2010年第3期409-412,共4页
研究了Pichia fermentans酵母菌产多糖YP5的单糖组成和结构。将酵母菌进行超声破碎后,采用乙醇沉淀法得到粗多糖,然后进行DEAE-纤维素色谱柱分离,得到均一的水溶性多糖YP5。经气相色谱分析表明,糖基由鼠李糖、阿拉伯糖、木糖、甘露糖、... 研究了Pichia fermentans酵母菌产多糖YP5的单糖组成和结构。将酵母菌进行超声破碎后,采用乙醇沉淀法得到粗多糖,然后进行DEAE-纤维素色谱柱分离,得到均一的水溶性多糖YP5。经气相色谱分析表明,糖基由鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖与半乳糖组成,其摩尔比为9.51∶1.33∶2.31∶0.94∶84.93∶0.96。乌氏粘度计法测得多糖的分子量为8.3×104。结合红外光谱和核磁共振1HNMR分析表明,该多糖YP5具有多糖特征性的红外吸收峰,存在酰胺结构,主要由β-D-葡聚糖组成。 展开更多
关键词 酵母多糖 纯化 单糖组成 结构
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从稀疏到结构化稀疏:贝叶斯方法 被引量:27
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作者 孙洪 张智林 余磊 《信号处理》 CSCD 北大核心 2012年第6期759-773,共15页
稀疏分解算法是稀疏表达理论和压缩感知理论中的核心问题,也是当前信号处理领域的一个热门话题。近年来,研究人员发现除了稀疏以外,如果引入稀疏系数之间的相关性先验信息,可以大大提高稀疏分解算法的精度,这种方法称为"结构化稀... 稀疏分解算法是稀疏表达理论和压缩感知理论中的核心问题,也是当前信号处理领域的一个热门话题。近年来,研究人员发现除了稀疏以外,如果引入稀疏系数之间的相关性先验信息,可以大大提高稀疏分解算法的精度,这种方法称为"结构化稀疏分解算法"。本文归纳和总结了从稀疏到结构化稀疏的信号模型,并且介绍了两种不同的贝叶斯稀疏(或者结构化稀疏)算法,以及从稀疏到结构化稀疏贝叶斯稀疏分解算法的扩展。同时,本文还介绍了结构化稀疏分解算法在医学信号处理和语音信号处理中的应用。 展开更多
关键词 压缩感知 稀疏理论 结构化稀疏分解算法 贝叶斯压缩感知
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西南天山前陆盆地侏罗纪-白垩纪盆山格局——来自碎屑锆石年代学的证据 被引量:3
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作者 杨威 郭召杰 +3 位作者 姜振学 Gloria Heilbronn 张晨 王思维 《大地构造与成矿学》 EI CAS CSCD 北大核心 2017年第3期533-550,共18页
目前对天山地区,特别是天山南缘中生代盆山格局认识尚存分歧。本文着眼于侏罗纪-白垩纪这一盆山演化关键阶段,利用碎屑锆石LA-ICP-MS U-Pb定年法对西南天山前陆盆地康苏剖面中侏罗统杨叶组、下白垩统克孜勒苏群沉积开展物源分析。发现... 目前对天山地区,特别是天山南缘中生代盆山格局认识尚存分歧。本文着眼于侏罗纪-白垩纪这一盆山演化关键阶段,利用碎屑锆石LA-ICP-MS U-Pb定年法对西南天山前陆盆地康苏剖面中侏罗统杨叶组、下白垩统克孜勒苏群沉积开展物源分析。发现中侏罗统杨叶组碎屑锆石U-Pb年龄分布于369~2687 Ma间,基本分布在369~404 Ma(约占4%)、418~501 Ma(约占19%)和544~2687 Ma(约占77%)3个范围;下白垩统克孜勒苏群碎屑锆石U-Pb年龄分布于243~2820 Ma间,集中于253~414 Ma(约占35%)、423~489 Ma(约占27%)和668~2820 Ma(约占37%)3个范围。中侏罗统碎屑锆石年龄分布范围广,各年龄组分均较突显,反映中侏罗世西南天山前缘流域体系宽广,天山内各主要源区均得到沟通,物源范围广阔。下白垩统克孜勒苏群锆石年龄分布明显集中,反映早白垩世西南天山前缘源区范围有所缩小。西南天山前缘与库车前陆盆地的物源构成在中侏罗世存在一定差异,而在早白垩世呈现相似特征。包括西南天山前陆盆地在内的天山南缘或于早白垩世经历一期小规模构造反转,导致山-盆构造分异与抬升-剥蚀增强。 展开更多
关键词 西南天山 碎屑锆石U-PB年龄 物源 盆山格局 构造反转
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远红外Ge-Ga-Te-Ag硫系玻璃性能研究(英文) 被引量:2
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作者 程辞 王训四 +8 位作者 徐铁峰 祝清德 廖方兴 孙礼红 潘章豪 刘硕 戴世勋 沈祥 Xiang-hua ZHANG 《光子学报》 EI CAS CSCD 北大核心 2015年第11期25-29,共5页
采用传统的熔融-淬冷法制备了一系列的(Ge15Ga10Te75)100-x(Ag)x硫系玻璃样品.通过X射线衍射、差式扫描量热法、傅里叶红外光谱仪等测试了玻璃样品的热学及光学性能.结果表明该玻璃具有良好的非晶态特性和热稳定性,玻璃开始析晶温... 采用传统的熔融-淬冷法制备了一系列的(Ge15Ga10Te75)100-x(Ag)x硫系玻璃样品.通过X射线衍射、差式扫描量热法、傅里叶红外光谱仪等测试了玻璃样品的热学及光学性能.结果表明该玻璃具有良好的非晶态特性和热稳定性,玻璃开始析晶温度和玻璃转变温度的差值都超过了100℃.随着Ag含量的增加,玻璃的吸收截止边产生了红移.通过提纯,Ge-Ga-Te-Ag玻璃在1.8-20μm有着较宽且平坦的红外光学窗口.Ge-Ga-Te-Ag玻璃组分的优良性质使其在红外领域具有广阔的应用前景. 展开更多
关键词 远红外 光学性质 热稳定性 硫系玻璃 红外光学窗口
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