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Fabrication of ultrafine Nd-Fe-B powder by a modified reduction-diffusion process

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Rare Metals 2006年第Z2期25卷 223-226页

作者： jANG T.S. LEE D.H. cHOI c.j. SEO W.S. LEE Y.H. Department of Electronic Materials Engineering Sunmoon University Korea Powder Materials Research center Korea Institute of Machinery and Materials Korea Advanced Materials Analysis & Evaluation center Korea Institute of Ceramic Engineering and Technology Korea

In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (R/D) process. And, unlike the conventional R/D process, calcium reduction that is a crucial step for the formation of Nd2Fe14B was performed without conglomerating the precursor with ca powder. By adopting this modified process, it is possible to synthesize the hard magnetic Nd2Fe14B at the reaction temperature as low as 850 ℃. The average size of Nd2Fe14B particles that are uniformly distributed in the optimally treated powder was cles were enclosed with thin layers of Nd-rich phase. Typical magnetic properties of such powder without eliminating impurity caO were iHc=～5.9 kOe, Br=～5.5 kG, and (BH)max=～6 MGOe.

关键词： NdFeB powder spray drying reduction-diffusion process Nd2Fe14B magnetic powder

On the analytical solution of transient friction in channel flows

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1447-1466页

作者： F.j.GARcíA-GARcíA P.FARINAS-ALVARINO Department of Naval&Industrial Engineering Polytechnic School of EngineeringUniversity of A CorunaCampus Industrial de FerrolFerrol 15403A CorunaSpain Integraciones Técnicas de Seguridad S.A.Pol.Ind.Espiritu SantoC/Nobel15Cambre 15650A CorunaSpain

The transient friction in channel mean flows is the sum of two contributions,i.e.,the underlying laminar flow(ULF)and the purely turbulent component(PTc),and the contributions are analyzed separately by theoretical *** is found that,the transient friction may be higher or remarkably lower than that in equal-Reynolds number steady-state *** universal time constant for plane-parallel laminar flows is reported,and the role of the time constant in a turbulent mean flow is *** is shown that the time constant is related to the turbulence's frozen ***,a study of the logarithmic layer during the transient flow is accomplished,which shows that the logarithmic layer is destroyed.

关键词： transient friction transient flow unsteady channel flow

Seasonal changes in Hermit Thrush (catharus guttatus) song syntax

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Avian Research 2024年第2期15卷 172-179页

作者： Sean P.Roach Luke c.McLean jeff W.MacLeod Leslie S.Phillmore Psychology Department University of New Brunswick Saint John100 Tucker Park RoadSaint JohnNBCanada Department of Psychology and Neuroscience Dalhousie University1355 Oxford StHalifaxNSB3H 4J1Canada

In many songbird species,birdsong features phonological syntax,meaning that the units within their vocal se-quences are ordered in a non-random way that adheres to a *** such syntactical patterns have been richly described in many species,comparatively little is known about how those patterns contribute to song achieving its important *** each of song’s main functions,territorial defense and mate attraction,evidence of a role for syntax is *** species for which syntax has been thoroughly described is the Hermit Thrush(catharus guttatus),which presents song types from their repertoires in a semi-predictable order and,in doing so,rapidly cycle up and down the frequency *** objective of the present study was to explore the importance of song syntax in the Hermit Thrush through a within-subject examination of how measures of syntax,such as the predictability of song type order within song sequences,shift over the breeding *** hypothesized that,if such syntactical characteristics are important to breeding behaviour,they would be most prominent at the start of the breeding season when activity associated with territory establishment and mate attraction is most *** revealed that,as predicted,the rigidness of song type ordering within se-quences was highest at the start of the season and declined *** song type sequences were most predictable at the vitally important early part of the breeding season fit our hypothesis that this aspect of song syntax is important to song’s functions related to territory establishment and/or mate *** work will clarify whether that role relates to one of song’s two main functions or serves song transmission in some broader way.

关键词： Birdsong Hermit Thrush Seasonal change Stereotypy Syntax

crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,ca) red phosphors for white light emitting diodes

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journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal Khajuria M.Manhas A.K.Bedyal Ankush Vij H.c.Swart Vinay Kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StateP.O.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and Lica(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of Lica(PO_(3))_(3):Eu^(3+)such as commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

Hepatitis B virus genotypes in precision medicine of hepatitis Brelated hepatocellular carcinoma:Where we are now

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World journal of Gastrointestinal Oncology 2024年第4期16卷 1097-1103页

作者： caecilia H c Sukowati Sri jayanti Turyadi Turyadi David H Muljono claudio Tiribelli Eijkman Research center for Molecular Biology Research Organization for HealthNational Research and Innovation Agency of IndonesiaJakarta 10340Indonesia Liver cancer Unit Fondazione Italiana Fegato ONLUSTrieste 34149Italy Faculty of Medicine Hasanuddin UniversityMakassar 90245South SulawesiIndonesia Faculty of Medicine and Health University of SydneySydney 2050Australia

Hepatitis B virus(HBV)infection is a major player in chronic hepatitis B that may lead to the development of hepatocellular carcinoma(Hcc).HBV genetics are diverse where it is classified into at least 9 genotypes(A to I)and 1 putative genotype(j),each with specific geographical distribution and possible different clinical outcomes in the *** diversity may be associated with the precision medicine for HBV-related Hcc and the success of therapeutical approaches against Hcc,related to different pathogenicity of the virus and host *** Editorial discusses recent updates on whether the classification of HBV genetic diversity is still valid in terms of viral oncogenicity to the Hcc and its precision medicine,in addition to the recent advances in cellular and molecular biology technologies.

关键词： Hepatitis B virus Hepatocellular carcinoma Genotypes Pathogenesis Precision medicine

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak David Zitoun Department of chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWcNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/c while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWcNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Management of distal cholangiocarcinoma with arterial involvement: Systematic review and case series on the role of neoadjuvant therapy

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World journal of Gastrointestinal Surgery 2024年第8期16卷 2689-2701页

作者： Lewis A Hall Duncan Loader Santiago Gouveia Marta Burak james Halle-Smith Peter Labib Moath Alarabiyat Ravi Marudanayagam Bobby V Dasari Keith j Roberts Syed S Raza Michail Papamichail David c Bartlett Robert P Sutcliffe Nikolaos A chatzizacharias Department of Hepatopancreatobiliary Surgery and Liver Transplantation University Hospitals Birmingham NHS Foundation TrustBirmingham B152GWUnited Kingdom Institute of Immunology and Immunotherapy University of BirminghamBirmingham B152TTUnited Kingdom college of Medical and Dental Sciences University of BirminghamBirmingham B152TTUnited Kingdom Institute of clinical Sciences University of BirminghamBirmingham B152TTUnited Kingdom

BAcKGROUND The use of neoadjuvant therapy(NAT)in distal cholangiocarcinoma(dccA)with regional arterial or extensive venous involvement,is not widely accepted and evidence is *** To synthesise evidence on NAT for dccA and present the experience of a highvolume tertiary-centre managing dccA with arterial *** A systematic review was performed according to PRISMA guidance to identify all studies reporting outcomes of patients with dccA who received *** patients from 2017 to 2022 who were referred for NAT for dccA at our centre were retrospectively collected from a prospectively maintained *** characteristics,NAT type,progression to surgery and oncological outcomes were *** Twelve studies were *** definition of“unresectable”locally advanced dccA was *** studies reported outcomes for 9 patients who received NAT for dccA with extensive vascular involvement.R0 resection rate ranged between 0 and 100%but without survival benefit in most *** studies considered either NAT in resectable dccA or inclusive with extrahepatic *** presented case series includes 9 patients(median age 67,IQR 56-74 years,male:female 5:4)referred for NAT for borderline resectable or locally advanced *** patients progressed to surgery and 2 were *** patient died at 14 months with evidence of recurrence at 6 months and the other died at 51 months following recurrence 6 months *** Evidence for benefit of NAT is *** on criteria for uniform definition of resectability for dccA is *** propose using the established National-comprehensive-cancer-Network®criteria for pancreatic ductal adenocarcinoma.

关键词： cholangiocarcinoma Neoadjuvant therapy Arterial involvement Locally advanced Systematic review

The evolving roles of Wnt signaling in stem cell proliferation and differentiation, the development of human diseases, and therapeutic opportunities

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Genes & Diseases 2024年第3期11卷 155-187页

作者： Michael Yu Kevin Qin jiaming Fan Guozhi Zhao Piao Zhao Wei Zeng connie chen Annie Wang Yonghui Wang jiamin Zhong Yi Zhu William Wagstaff Rex c.Haydon Hue H.Luu Sherwin Ho Michael j.Lee jason Strelzow Russell R.Reid Tong-chuan He School of Medicine Rosalind Franklin University of Medicine and ScienceNorth ChicagoIL 60064USA Molecular Oncology Laboratory Department of Orthopedic Surgery and Rehabilitation MedicineThe University of Chicago Medical CenterChicagoIL 60637USA Ministry of Education Key Laboratory of Diagnostic Medicine and Department of Clinical BiochemistryThe School of Laboratory MedicineChongqing Medical UniversityChongqing 400016China Department of Orthopedic Surgery The First Affliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Urology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of clinical Laboratory Medicine Shanghai Jiaotong University School of MedicineShanghai 200000China Department of Orthopaedic Surgery Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Laboratory of craniofacial Suture Biology and Development Department of Surgery Section of Plastic SurgeryThe University of Chicago Medical CenterChicagoIL 60637USA Department of Neurology The First Dongguan Affiliated HospitalGuangdong Medical UniversityDongguanGuangdong 523475China

The evolutionarily conserved Wnt signaling pathway plays a central role in develop-ment and adult tissue homeostasis across *** proteins are secreted,lipid-modified signaling molecules that activate the canonical(β-catenin dependent)and non-canonical(β-catenin independent)Wnt signaling *** behaviors such as proliferation,differ-entiation,maturation,and proper body-axis specification are carried out by the canonical pathway,which is the best characterized of the known Wnt signaling *** signaling has emerged as an important factor in stem cell biology and is known to affect the self-renewal of stem cells in various *** includes but is not limited to embryonic,hematopoietic,mesenchymal,gut,neural,and epidermal stem *** signaling has also been implicated in tumor cells that exhibit stem cell-like *** signaling is crucial for bone formation and presents a potential target for the development of therapeutics for bone *** surprisingly,aberrant Wnt signaling is also associated with a wide variety of diseases,including *** of Wnt pathway members in cancer can lead to unchecked cell proliferation,epithelial-mesenchymal transition,and ***,advances in the understand-ing of dysregulated Wnt signaling in disease have paved the way for the development of novel therapeutics that target components of the Wnt *** with a brief overview of the mechanisms of canonical and non-canonical Wnt,this review aims to summarize the cur-rent knowledge of Wnt signaling in stem cells,aberrations to the Wnt pathway associated with diseases,and novel therapeutics targeting the Wnt pathway in preclinical and clinical studies.

关键词： β-catenin cancer canonical Wnt Disease Non-canonical Wnt Stem cells Targeted therapy Wnt signaling

Metabolic syndrome and the urinary microbiome of patients undergoing percutaneous nephrolithotomy

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Asian journal of Urology 2024年第2期11卷 316-323页

作者： Ryan A.Dornbier chirag P.Doshi Shalin c.Desai Petar Bajic Michelle Van Kuiken Mark Khemmani Ahmer V.Farooq Larissa Bresler Thomas M.T.Turk Alan j.Wolfe Kristin G.Baldea Loyola University Medical center Department of UrologyMaywoodILUSA Loyola University chicago Department of Microbiology and ImmunologyMaywoodILUSA

Objective:To identify possible stone-promoting microbes,we compared the profiles of microbes grown from stones of patients with and without metabolic syndrome(MetS).The association between MetS and urinary stone disease is well established,but the exact pathophysiologic relationship remains *** evidence suggests urinary tract dysbiosis may lead to increased nephrolithiasis ***:At the time of percutaneous nephrolithotomy,bladder urine and stone fragments were collected from patients with and without *** sample types were subjected to expanded quantitative urine culture(EQUc)and 16 S ribosomal RNA gene ***:Fifty-seven patients included 12 controls(21.1%)and 45 MetS patients(78.9%).Both cohorts were similar with respect to demographics and non-MetS *** controls had uric acid stone *** EQUc,bacteria were detected more frequently in MetS stones(42.2%)compared to controls(8.3%)(p=0.041).Bacteria also were more abundant in stones of MetS patients compared to *** validate our EQUc results,we performed 16 S ribosomal RNA gene *** 12/16(75.0%)sequence-positive stones,EQUc reliably isolated at least one species of the sequenced *** were detected in both“infectious”and“non-infectious”stone ***:Bacteria are more common and more abundant in MetS stones than control *** findings support a role for bacteria in urinary stone disease for patients with MetS regardless of stone composition.

关键词： Nephrolithiasis Urolithiasis Metabolic syndrome Urinary microbiome Percutaneous nephrolithotomy