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Photonics Research 2019年第6期7卷 608-614页

作者： J.ALANIZ-BAYLON m.DURAN-SANCHEZ R.I.ALVAREZ-TAmAYO B.POSADA-RAmIREZ m.bello-jimenez B.IBARRA-ESCAmILLA A.A.CASTILLO-GUZmAN E.A.KUZIN Instituto Nacional de Astrofísica óptica y Electrónica (INAOE)L. E. Erro 1 Sta. Ma. Tonantzintla Pue. 72824 Mexico CONACyT-Instituto Nacional de Astrofísica óptica y ElectrónicaA. P. 51 y 216 Pue. 72000 Mexico CONACyT-Universidad Autónoma de Nuevo León Av.Universidad S/NSan Nicolas de los Garza N. L. 66451 Mexico Instituto de Investigación en Comunicación óptica Universidad Autónoma de San Luis Potosí Av. Karakorum 1470 S. L. P. 78210 Mexico Universidad Autónoma de Nuevo León Av.Universidad S/NSan Nicolas de los Garza N. L. 66451 Mexico

We report the experimental investigation of an all-fiber multi-wavelength passively Q-switched Er/Yb laser with simultaneous gain-switched pulsed operation by using a thulium-doped fiber as a saturable *** emission is obtained in three wavelength regions with central peaks at around 1546 nm, 1561 nm, and1862 nm. multi-wavelength emission with separation of approximately 1 nm is obtained around the wavelength regions of 1546 nm and 1561 nm. Stable laser pulses are generated in the pump power range from 3.6 W to7.3 W.

关键词： Fiber laser multi-wavelength

Distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naphthofurans in source rock extracts from Niger Delta basin,Nigeria

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Acta Geochimica 2020年第6期39卷 973-987页

作者： Abiodun B.Ogbesejana Oluwasesan m.bello Department of Applied Chemistry Federal University Dutsin-MaP.M.B.5001Dutsin-MaKatsina StateNigeria

The distribution and geochemical significance of dibenzofurans,phenyldibenzofurans and benzo[b]naptho-furans in source rocks from Niger Delta basin,Nigeria,were investigated by Rock-Eval pyrolysis and gas chro-matography--mass spectrometry(GC--mS).The data obtained from the source rocks evaluation showed that the rock samples contained type 1/III kerogen capable of generating oil and gas and were within immature to early mature *** relative abundance of the Cor,C1-and C2-dibenzofurans range from 1.75%to 29.82%,27.60%to 40.52%and 29.66%to 6889%,*** diben-zofurans were dominated by *** the C1-dibenzofurans,2-+3-methyldibenzofuran was the most abundant in the rock samples while 1-methy ldibenzofuran appeared to be the *** relative abundance of benzo[b]naphtho[1,2-d]furan(1,2]BNF),benzo[b]naph-tha[2,1-d]furan(2.1]BNF)and benzo[b]naphtha[2,3-d]fu-ran([2.3]BNF)in the rock extracts range from 12.01%to 52.58%,32.61%to 75.219%and 10.27%to 52.43%.The wide range of values recorded for the three isomers of benzo[b lnapthofurans in the samples suggest source rocks formed from mixed organic *** the pheny ldibenzofuran isomers,4-pheny ldibenzofuran was the most abundant while 1-phenyldibenzofuran was the *** ratio-1(PhFR-1)and pheny ldibenzofuran ratio-2(PhFR-2)values range from 0.13 to 1.20 and 0.11 to 2.11,*** resuls showed that the relative abundance of PhFR-1 and PhFR-2 increase gradually with increasing burial depth and maturity(VRo≤0.77%,mPI-1≤*** s 443℃),and have a good correlations with calculated vitrinite ***-I and maximum Temperature(Tmax)-This range of values suggested immature to early mature source *** source rocks were found to have shale and coul lithologics and deposited in a lacustrine/fuvial deltaic settings within immature to early mature stages based on the distribution of dibenzofurans,pheny ldiben-zofurans and benzo[b]naphthofurans in the source rock

关键词： Dibenzofurans Benzo[b]napthofurans Source rocks Niger delta Gas chromatography-mass spectrometry

CFD simulation of pumping ventilation in a three-story isolated building with internal partitioning:Effects of partition widths,heights and locations

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Building Simulation 2024年第2期17卷 267-284页

作者： Huai-Yu Zhong Jie Sun Chao Lin Song-Heng Wu Jin Shang Hideki Kikumoto Fu-Ping Qian Carlos jimenez-Bescos Fu-Yun Zhao School of Energy and Environment Anhui University of TechnologyMa-An-ShanAnhui Province243002China State Key Laboratory of Green Building in Western China Xi’an University of Architecture&TechnologyXi’anShaanxi ProvinceChina School of Power and mechanical Engineering Wuhan UniversityWuhanHubei Province430072China Institute of Industrial Science The University of Tokyo4-6-1 KomabaMeguro-kuTokyo153-8505Japan School of Built and Natural Environment University of DerbyDerbyUK

Pumping ventilation(PV),a special single-sided ventilation(SSV),has been certified as an effective strategy to improve the air exchange rate of ***,most studies targeted on the single space,and few studies have been focused on the effect of internal partitioning on *** paper aims to evaluate the ventilation performance of PV influenced by different configurations of internal *** fluid dynamics(CFD)simulation was used to predict the flow fields and ventilation *** width(w/H),height(h/H)and location(d/H)are the three main internal partition parameters considered in this *** simulation results showed that the total,mean and fluctuating ventilation rates all decrease with wider internal *** normalized total ventilation rate decreases by 7.6%when w/H is increased from 50%to 75%.However,the reduction rate is only 0.23%between w/H=0 and 25%,and only 0.61%between w/H=25%and 50%.The ventilation rate is hardly reduced by increasing the partition width when w/H50%.Increasing the partition height will reduce the mean ventilation rate but promote the fluctuating and total ventilation rate in some *** increase of total ventilation rate by 1.4%is observed from h/H=50%to 75%.The ventilation rate is larger when the internal partition is attached to the leeward or windward *** total,mean and fluctuating ventilation rates for d/H=50%are relatively higher than d/H=0 by 1.5%,3.1%and 0.8%,*** the internal partition should be mounted attached to the windward wall so as to obtain the greatest pumping ventilation *** periodicity of pumping flow oscillation and pumping frequency are independent of the partition *** peak power of pumping flow is the lowest for the widest internal partition and is negatively affected by the partition height,but it generally has a positive correlation with the distance between the partition and leeward wa

关键词： pumping ventilation single-sided ventilation internal partitioning periodic oscillation ventilation rate

Driving factors behind multiple populations

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Science China(Physics,mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun Huang Baitian Tang Chengyuan Li Doug Geisler mario mateo Ying-Yi Song Holger Baumgardt Julio A.Carballo-bello Yue Wang Jundan Nie Bruno Dias JoséG.Fernández-Trincado School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-macao Greater Bay Area Zhuhai 519082China Departamento de Astronomía Universidad de ConcepcionConcepcionChile Instituto de Investigación multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile Departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile Department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap Department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada School of mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia Instituto de Alta Investigación Universidad de TarapacáAricaChile CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile Instituto de Astronomía Universidad Católica del NorteAntofagastaChile

Star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical ***,the presence of chemical anomalies in globular clusters(GCs),called multiple stellar populations(mPs),has challenged star formation theories in dense *** studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of *** the limit between clusters with/without mPs in physical parameter space is crucial to reveal the driving mechanism behind their *** this study,we look for mP signals in Whiting 1,which is traditionally considered a young *** the magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting *** measured the C and N abundances from the CN and CH spectral indices.C and N abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that mPs are absent from Whiting *** these findings with literature studies,we propose a limit in the metallicity *** compactness index parameter space,which relatively clearly separates star clusters with/without mPs(GCs/open clusters).This limit is physically *** a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex *** proposed limit also impacts our understanding of the formation of the Sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 Gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for mP formation.

关键词： stellar galactic galaxy

Three-dimensional analysis of age and sex differences in femoral head asphericity in asymptomatic hips in the United States

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World Journal of Orthopedics 2024年第8期15卷 754-763页

作者： mahad m Hassan Aliya G Feroe Brenton W Douglass Andrew E jimenez Benjamin Kuhns Charles F mitchell Robert L Parisien Daniel A maranho Eduardo N Novais Young-Jo Kim Ata m Kiapour Department of Orthopedic Surgery University of MinnesotaMinneapolisMN 55454United States Department of Orthopedic Surgery TRIA Orthopaedic CenterBloomingtonMN 55122United States Department of Orthopedic Surgery Boston Children’s HospitalBostonMA 02115United States Department of Orthopedic Surgery Mayo ClinicRochesterMN 55901United States Department of Orthopaedics and Rehabilitation Yale School of MedicineNew HavenCT 06510United States Department of Orthopedic Surgery American Hip Institute Research FoundationDes PlainesIL 60018United States Department of Orthopedic Surgery Mount SinaiNew YorkNY 10029United States Department of Biomechanics Medicineand Rehabilitation of the Locomotor SystemRibeirao Preto Medical SchoolUniversity of São PauloRibeirao Preto 14048-900São PauloBrazil

BACKGROUND The sphericity of the femoral head is a metric used to evaluate hip pathologies and is associated with the development of osteoarthritis and femoral-acetabular *** To analyze the three-dimensional asphericity of the femoral head of asymptomatic pediatric *** hypothesized that femoral head asphericity will vary significantly between male and female pediatric hips and increase with age in both *** Computed tomography scans were obtained on 158 children and adolescents from a single institution in the United States(8-18 years;50%male)without hip *** femoral measurements including the femoral head diameter,femoral head volume,residual volume,asphericity index,and local diameter difference were used to evaluate femoral head *** In both sexes,the residual volume increased by age(Pmaller femoral head size in older ages(>13 years)in females,there were no sex-differences in residual volume and aspherity *** were no age-related changes in mean diameter difference in both sexes(P=0.07)with no significant sex-differences across different age groups(P=0.06).In contrast,there were significant increases in local aspherity(maximum diameter difference)across whole surface of the femoral head and all quadrants except the inferior regions in males(P=0.03).There were no sex-differences in maximum diameter difference at any regions and age group(P>0.05).Increased alpha angle was only correlated to increased mean diameter difference across overall surface of the femoral head(P=0.024).CONCLUSION There is a substantial localized asphericity in asymptomatic hips which increases with age *** 2D measured alpha angle can capture overall asphericity of the femoral head,it may not be sensitive enough to represent regional asphericity patterns.

关键词： Hip Femoral head Sphericity Skeletal growth Sex differences

Geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Basin,Nigeria

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Acta Geochimica 2021年第2期40卷 184-198页

作者： Abiodun B.Ogbesejana Oluwasesan m.bello Tijjani Ali Uduma A.Uduma Kamaluddeen S.Kabo Oluwadurotimi O.Akintade Department of Applied Chemistry Federal University Dutsin-MaP.M.B.5001Dutsin-MaKatsina StateNigeria Department of Chemical Sciences Koladaisi UniversityIbadanOyo StateNigeria

Tricyclic and tetracyclic terpanes are important constituents of crude oil and source rock ***,they have not been reported in the Offshore Niger Delta Basin,***,the present study investigated the geochemical significance of tricyclic and tetracyclic terpanes in source rock extracts from the Offshore Niger Delta Bain,Nigeria with gas chromatography-mass spectrometry(GC-mS).The total relative abundances of tricyclic terpanes,C_(19)TT-C_(21)TT,and C_(23) TT in the rock samples ranged from 82.50 to 96.37%,50.08 to 74.17%,and 25.83 to 49.92%,*** values showed the source rocks were formed from a mixed origin(terrestrial and marine).Among the tricyclic and tetracyclic terpanes identified in the rock extracts,the conventional(C_(20)TT,C_(23)TT,C_(24)TT,C_(24)TeT)and recent(Y1,X1,Z1)were more prominent than all others,indicating mixed input of terrigenous and marine organic *** C_(24)TT/C_(23)TT,C_(24)TeT/(C_(24)TeT+C_(26)TT),C_(19)TT/C_(23)TT,C_(20)TT/C_(23)TT,C_(25)TT/C_(24)TeT,C_(25)TT/C_(26)TT,C_(19)TT/C_(20)TT,C_(24)TeT/C_(26)TT,Z1/(Z1+C_(24)TT),and Y1/(Y1+C_(24)TT)in the rock samples range from 0.33 to 1.30,0.76 to 0.90,0.18 to 0.73,0.34 to 1.05,0.33 to 1.74,0.30 to 1.39,0.31 to0.89,1.66 to 4.33,0.36 to 0.83,and 0.34 to 0.79,*** values further showed that the rock samples were formed from mixed input of terrigenous and marine organic matter and deposited under oxic to suboxic conditions in lacustrine-fluvial/deltaic ***,the C_(24)TeT/C_(20)-26TT,C_(24)TeT/C_(30)HOP,and C_(23)TT/C_(30)HOP ranged from 0.16 to 0.45,0.02 to 0.42,and 0.01 to 0.48,*** range of values suggests that source rocks were within immature to early mature ***,this study showed that tricyclic and tetracyclic terpanes were effective in determining the origin,depositional environments,and thermal maturity of source rocks in the Niger Delta Basin,Nigeria.

关键词： Tricyclic terpanes Tetracyclic terpanes Source rocks Niger delta Gas chromatography-mass spectrometry(GC-mS)

Cervical myelopathy: Diagnostic Aspects, Surgical Treatment and Evolution of Patients Operated upon in Yaounde

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Open Journal of modern Neurosurgery 2024年第1期14卷 72-82页

作者： bello Figuim Djoubairou Ben Ousmanou Oumarou Haman Nassourou Ndome Toto Orlande Amadou Tidjani Djientcheu Vincent de Paul Yaounde Central Hospital Faculty of Medicine and Biomedical Sciences of the University of Yaounde 1 Yaounde Cameroon Yaounde military Hospital Faculty of Medicine and Pharmaceutical Sciences of the University of Douala Douala Cameroon Douala General Hospital Faculty of Medicine and Pharmaceutical Sciences of the University of Douala Douala Cameroon Higher Institute of Health Sciences Université des Montagnes Bangangté Cameroon

Introduction: Although cervical myelopathy is the most common degenerative cervical spine pathology in adults, the indications and approaches of surgical treatment have not yet been clearly defined in the literature. Very few studies exist regarding these aspects in our setting, and they are mostly outdated. This study aimed to describe the diagnostic aspects, current surgical treatment with technical improvements, and progression in patients. Patients and methods: We conducted a multicentre retrospective descriptive study over a 10-year period between January 2011 and January 2020 in three referral centres in Yaoundé. All patients who underwent surgery for cervical myelopathy were included. Results: Fifty-two patients were recruited. The rate of operated cervical myelopathies among all degenerative spinal pathologies was 14.05%. The m/F sex ratio was 3/1, and the average age was 52 ± 10 years. All included patients had gait problems, 90.38% demonstrated motor deficiency, and 67.30% experienced at least three levels of compression. Surgery was decided based on the Nurick grade;a posterior approach was applied to 86.54% of patients. Postoperative progression showed a neurological improvement of 82% with an average follow-up of 4 years. Conclusion: In this study, the patients who underwent surgery were relatively young, their clinical presentations were mostly advanced, and surgical management showed good results in well-selected cases.

关键词： Cervical myelopathy Diagnosis Treatment Evolution Cameroon

Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil m.Patange P.m.Dighe Sher Singh meena Abdullah GAl-Sehemi mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morphology of the hexaferrites was analyzed from the FESEm profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.m,and mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity m?ssbauer spectroscopy

multi-tissue transcriptomics of a unique monozygotic discordant twin case of severe progressive osseous heteroplasia

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Genes & Diseases 2024年第3期11卷 22-25页

作者： Alberto Gomez-Carballa maria Jose Curras-Tuala Sara Pischedda miriam Cebey-Lopez Jose Gomez-Rial Irene Rivero-Cale Jacobo Pardo-seco Xabier bello Sandra Viz-Lasheras Antonio Justicia-Grande Julian montoto-Louzao Alba Camino-mera Isabel Ferreiros-Vidal maximo Fraga Jose RAntunez Rodolfo Gomez Federico martinon-Torres Antonio Salas Genetics Vaccines and Infections Research Group(GENVIP)Instituto de Investigacion Sanitaria de SantiagoSantiagode CompostelaGalicia 15706Spain Translational Pediatrics and Infectious Diseases Department of PediatricsHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Laboratorio de Inmunologia Servicio de Andlisis ClinicosHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Unidade de Xenetica Instituto de Ciencias Forenses(INCIFOR)Facultade de MedicinaUniversidade de Santiago de Compostelaand GenPoB Research GroupInstituto de Investigacion SanitariaHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain musculoskeletal Pathology Group Instituto de Investigacion Sanitaria de SantiagoServicio Galego de Saude(SERGAS)Santiago de CompostelaGalicia 15706Spain Department of Pathology Hospital Clinico Universitario de Santiago de Compostela(SERGAS)Galicia 15706Spain Unidad Integrada de BiobancosBiomodelos 3D y Modelos Animales IDIS(lnstituto de Investigacion Sanitaria de Santiagode Compostela)Galicia15706Spain Centro de Investigacion Biomedica en Red de Enfermedades Respiratorias(CIBER-ES) MadridSpain

Progressive osseous heteroplasia(POH)is an ultra-rare autosomal dominant disabling disorder characterized by heterotopic ossification(HO).It is caused by heterozygous inactivating mutations in the GNAS(guanine nucleotide-binding protein alpha-stimulating activity polypeptide)***,the molecular mechanisms underlying HO remain poorly *** a treatment for POH is not yet available,the identification of the mechanisms driving POH in affected tissues using gene expression may be of great help to underestand the molecular basis of POH and develop new therapeutic approaches.

关键词： stimulating driving asi

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram