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Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.C.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(et)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to ch.nges in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim F.Magomedov Svetlana ch.Gagieva Dmitry A.Kurmaev yulia V.Nelyubina Evgenii K.Golubev Maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov Boris M.Bulychev Department of chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

Prevalence of Diabetes and Hypertension on World Diabetes Day 2022 in Guinea

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Open Journal of Endocrine and Metabolic Diseases 2024年第1期14卷 1-6页

作者： Mamadou Dian Mamoudou Diallo Mamadou Mansour Diallo Mamadou chérif Diallo Mamadou Alpha Diallo Alpha Mamadou Diallo Mody Abdoulaye Barry Kadija Dieng Abdoul Mazid Diallo El’Hadj Zainoul Bah Kadidiatou Bah Amatoulaye Diallo Amadou Kaké Naby Moussa Baldé Oumou Baldé Unité de Diabétologie H&#244pital régional de Labé Labe Guinea Université de Conakry Conakry Guinea Service de Diabétologie CHU Donka Conakry Guinea Fondation de Lutte Contre le diabète et MNT Conakry Guinea

Introduction: Diabetes mellitus and hypertension are chronic diseases that are on the rise and pose a major public health problem among the priorities of healthcare systems. Objectives: Determine the prevalence of diabetes and hypertension and describe the sociodemographic characteristics of those screened. Materials and Methods: This was a cross-sectional study organized during a diabetes and hypertension screening campaign that took place in Conakry and five (05) inland regions on November 14, 2022. Results: 2050 people were screened, of whom 33.12% were housewives, the average age was 44.78 ± 16.23 years, and 55.27% were women. The screening sites were the city of Conakry 741 (36.15%), the Labé region 424 (20.68%), the N’Zérékoré region 298 (14.54%), the Faranah region 241 (11.75%), the Mamou region 210 (10.24%) and the Boké region 136 (6.63%). The prevalence of diabetes and hypertension were respectively 12.5% and 43.38% for the Boké region;6.19% and 16.19% for the Mamou region;3.02% and 21.81% for the N’Zérékoré region;31.95% and 13.69% for the Faranah region;9.67% and 20.28% for the Labé region;2.83% and 20.28% for the city of Conakry. Conclusion: Despite the limitations of the study duration, our series highlighted the high prevalence of diabetes and hypertension among people screened on World Diabetes Day 2022. Raising public awareness of a healthy lifestyle is essential for the prevention and control of diabetes and hypertension.

关键词： Prevalence Diabetes Hypertension

Unmasking metabolic dependencies in pancreatic cancer: aberrant polyamine synthesis as a promising new therapeutic target

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Signal Transduction and Targeted Therapy 2023年第11期8卷 5151-5152页

作者： Gerrit Wolters-Eisfeld Thilo Hackert Cenap Güngör Department of General Visceral and Thoracic SurgeryUniversity Medical Center Hamburg-EppendorfHamburgGermany

In a recently published Nature article,Lee et *** distinct metabolic dependencies of pancreatic ductal adenocarcinoma(PDA)cells compared to normal tissue,and discovered that PDA cells exhibited a unique reliance on de novo ornithine synthesis from glutamine,rather than *** aberrant polyamine synthesis offers a promising therapeutic target for pancreatic cancer.

关键词： synthesis den depen

Development of stable, cold-adapted, temperature-sensitive/conditional lethal chimeric enterovirus A71 and coxsackievirus A16

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Virologica Sinica 2022年第5期37卷 769-773页

作者： Kaw Bing chua Qimei ng Tao Meng Qiang Jia Temasek Life Sciences Laboratory 1 Research LinkNational University of Singapore117604Singapore

Dear Editor,Coxsackievirus A16(CA16)and enterovirus A71(EV-A71)are the main causative agents of hand foot and mouth disease(HFMD)(Alexander et al.,1994).Besides HFMD,EV-A71 infection in young children can lead to a spectrum of other clinical diseases and associated neurological complications and mortality(Melnick JL.,1996).In recent decades,EV-A71 infections have become a major public health concern throughout the world,following the frequent occurrence of epidemics and outbreaks of HFMD associated with neurological complications and high mortality in young children(Ishimaru et al.,1980;Tagaya et al.,1981;chomnaitree et al.,1982;Samuda et al.,1987;Gilbert et al.,1988;Hayward et al.,1989;Lum et al.,1998;ch.ng et al.,1998;Liu et al.,2000;yang et al.,2011;Zeng et al.,2012).

关键词： mortality enterovirus

Transmission of the ychromosome microdeletion to a baby boy conceived after in tracytoplasmic sperm injection

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chinese Medical Journal 2001年第1期114卷 97-99页

作者： Tse JyM yeung WSB Lau EyL ng EHy Tam PC So WWK Tang MHy Lau et Ho PC Department of Obstetrics and Gynecology The University of HongKongHongKongChina

Subfertility can be caused by acquired or genetic factors. y chromosome microdeletion is one of the genetic factors associating with male infertility.1 Azoospermia factors (AZFa, AZFb and AZFc) have been mapped to different subregions in yq11.2 So far, two gene families, RNA-binding motif (RBM) and deleted in azoospermia (DAZ) from interval 6, were proposed as candidate spermatogenesis genes for AZF.3,4 Recent studies demonstrated that microdeletions were detected at a frequency of 5% to 18% in the AZF region of oligospermic and azoospermic men.5-7 With the development of assisted reproductive technologies, particularly intracytoplasmic sperm injection (ICSI), these men can now father a child and the genetic abnormalities in defective spermatozoa could be transmitted to future offspring. To examine the possible transmission of the y-chromosome microdeletion to the offspring via ICSI treatment, we performed both cytogenetic and molecular analyses of the y chromosome on both an infertile patient with y chromosome microdeletion and his offspring.

关键词： sperm

Association between the Different Phenotypes of Polycystic Ovary Syndrome and the Outcome in in Vitro Fertilization at Human Reproductive Center Paul et chantal Biya-yaoundé

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Open Journal of Obstetrics and Gynecology 2024年第1期14卷 18-28页

作者： ngono Akam Vanina ngah Minala Belinga etienne Belinga etienne Mpono Pascale Nyada Serges Onana y. Kasia cho Joselyne Kasia Florence Adjessa Abega Kasia Jean Marie Gynaecological Endoscopic Surgery and Human Reproductive Teach.ng Hospital Yaoundé Cameroon Department of Gynecology and Obstetrics Faculty of Medicine and Biomedical Sciences University of Yaoundé 1 Yaoundé Cameroon

Background: In Vitro Fertilization/Intracytoplasmic Sperm Injection (IVF/ICSI) represents the final step in the management of Polycystic Ovarian Syndrome (PCOS). Our objective was to study the association between PCOS phenotypes and IVF/ICSI results in women admitted to Gynaecological Endoscopic Surgery and Human Reproductive Teach.ng Hospital (chRACERH). Material and Method: We carried out a cohort study with historical-prospective data collection over a period of seven years (January 2016 to March 2023) at chracerh. PCOS patients were subdivided into 4 subgroups A, B, C and D. Results: We recruited 128 patients including 64 PCOS patients divided into four phenotypes and 64 non-PCOS patients constituting the control group. Phenotype D without hyperandrogenism had used the lowest dose of gonadotropins, i.e. 1939.7 ± 454.3 IU, and had produced a greater quantity of estradiol on the day ovulation was triggered (6529.8 ± 4324.8 ng/ml). The average number of punctured follicles and mature oocytes were higher in the phenotype D group. Ovarian hyperstimulation syndrome (OHSS) occurred mainly in phenotype D (3/35), with an estimated prevalence of 2.3%. The fertilization rate seemed lower in the hyperandrogenic phenotypes A, B, C compared to the group without hyperandrogenism without significant difference (p = 0.461). The biological pregnancy rate and live birth rate were comparable between the different groups. Conclusion: Phenotype D used less dose of gonadotropins. Biological pregnancy and live birth rates were comparable between the different phenotypes.

关键词： Phenotype Polycystic Ovarian Syndrome IVF/ICSI Prognosis chRACERH

Optimizing laser coupling,matter heating,and particle acceleration from solids using multiplexed ultraintense lasers

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Matter and Radiation at Extremes 2024年第4期9卷 16-28页

作者： Weipeng yao Motoaki Nakatsutsumi Sébastien Buffechoux Patrizio Antici Marco Borghesi Andrea Ciardi Sophia N.chen Emmanuel d’Humières Laurent Gremillet Robert Heathcote Vojtech Horny Paul McKenna Mark N.Quinn Lorenzo Romagnani Ryan Royle Gianluca Sarri yasuhiko Sentoku Hans-Peter Schlenvoigt Toma Toncian Olivier Tresca Laura Vassura Oswald Willi Julien Fuchs LULI-CNRS CEASorbonne UniversitéEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Université Observatoire de ParisUniversité PSLCNRSLERMAF-75005 ParisFrance INRS-EMT 1650 BoulLionel-BouletVarennesQuebec J3X 1S2Canada Center for Plasma Physics School of Mathematics and PhysicsQueen’s University BelfastBelfast BT71NNUnited Kingdom “Horia Hulubei”National Institute for Physics and Nuclear Engineering 30 Reactorului StreetRO-077125 Bucharest-MagureleRomania University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance CEA DAMDIFF-91297 ArpajonFrance Université Paris-Saclay CEALMCE91680 Bruyères-le-ChatelFrance Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUnited Kingdom SUPA Department of PhysicsUniversity of StrathclydeGlasgow G40NGUnited Kingdom Department of Physics University of NevadaRenoNevada 89557USA Institute of Laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan Institut fur Laser und Plasmaphysik Heinrich Heine Universitat DusseldorfDusseldorfGermany

Realizing the full potential of ultrahigh-intensity lasers for particle and radiation generation will require multi-beam arrangements due to technology ***,we investigate how to optimize their coupling with solid ***,we show that overlapping two intense lasers in a mirror-like configuration onto a solid with a large preplasma can greatly improve the generation of hot electrons at the target front and ion acceleration at the target *** underlying mechanisms are analyzed through multidimensional particle-in-cell simulations,revealing that the self-induced magnetic fields driven by the two laser beams at the target front are susceptible to reconnection,which is one possible mechanism to boost electron *** addition,the resistive magnetic field generated during the transport of the hot electrons in the target bulk tends to improve their *** simulations also indicate that such effects can be further enhanced by overlapping more than two laser beams.

关键词： laser acceleration particle

High-dose biotin neither fosters remyelination nor stimulates malonyl coenzyme A synthesis in the regenerating nerve

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Neural Regeneration Research 2023年第7期18卷 1623-1624页

作者： Fabian Szepanowski Rebecca D.Steubing Cansu Güngör Jaqueline Zipfel Anne K.Mausberg christoph Kleinschnitz Mark Stettner Department of Neurology and Center for Translational Neuro-and Behavioral Sciences(C-TNBS) University Medicine EssenUniversity Duisburg-EssenEssenGermany

Dear editor,Dysregulated inflammatory responses primarily account for damage to the central nervous system,however,neurodegenerative processes likely contribute to the pathophysiology of progressive forms of multiple sclerosis(MS).These pathophysiological aspects include axonal energy depletion and impaired remyelination capacity(Levin et al.,2014).The clinical efficacy of most disease-modifying therapies in MS to date has been achieved by targeting functions of the adaptive immune system(Cree et al.,2019;Szepanowski et al.,2021).

关键词： system synthesis neither