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Rietveld refinement and optical properties of SrWO_4:eu^(3+) powders prepared by the non-hydrolytic sol-gel method

Journal of Rare earths 2015年第2期33卷 113-128页

作者： P.F.S.Pereira I.C.Nogueira e.longo e.J.Nassar I.L.V.Rosa L.S.Cavalcante Chemistry Institute University of the State of Sao Paulo Julio de Mesquita Filho-UNESP Francisco DegniAraraquara-SP 14800-900 Brazil LIeC-Chemistry Department Federal University of Sao Carlos Via Washington Luis Km 235Sao Carlos-SP 13565-905 Brazil University of Franca-UNIFRAN Via Dr.Armando Sales de OliveiraNo.201 Franca-SP 14404-600 Brazil CCN-DQ-GeRATeC University of the State of Piauí Joao Cabral 2231 P.O.Box 391Terezina PI 64002-150 Brazil

We investigated the effect of annealing time on the structure and optical properties of Sr WO4：eu^3＋ powders prepared by the non-hydrolytic sol-gel method and heat treated at 800 ℃ for 2,4,8 and 16 *** and differential thermal analyses revealed that Sr WO4：eu^3＋ powders were obtained at about 800 ℃.X-ray diffraction patterns and Rietveld refinement data confirmed that all powders had a scheelite-type tetragonal ***-Raman and Fourier transform infrared spectra indicated structural order at short range and anti-symmetric stretching vibrations of O-W-O bonds associated with tetrahedral[WO4]*** properties were investigated by ultraviolet-visible（UV-vis）diffuse reflectance,and photoluminescence（PL）data which provided the evolution of quantum efficiency（η）and lifetime（τ）.UV-vis spectroscopy evidenced intermediate energy levels within the band gap of Sr WO4：eu^3＋ *** properties validated that the eu^3＋ electric-dipole（^5D0→^7F2）transition in PL emission spectra was dominant which proved that eu^3＋ ions were positioned in a site without an inversion center.[（^5D0→^7F2）/（^5D0→^7F1）]band ratios showed that eu^3＋ ions were located in a low symmetry *** PL emission,ηandτproved the dependence on the annealing time in the behavior of Sr WO4：eu3＋powders with a higher relative emission PL intensity as well as higherηandτvalues related to other samples when heat treated at 800℃ for 8 h.

关键词： SrWO4 Rietveld refinement optical band gap eu^(3+) +-rare earth luminescence

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Red-emitting CaWO4:eu^(3+),Tm^(3+)phosphor for solid-state lighting:Luminescent properties and morphology evolution

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Journal of Rare earths 2022年第2期40卷 226-233,I0002页

作者： L.X.Lovisa I.M.P.da Silva A.A.G.Santiago M.Siu Li e.longo C.A.Paskocimas M.R.D.Bomio F.V.Motta Institute of Physics and Chemistry.Federal University of Itajubd(UNIFeI) ItajubdMG37500-903Brazil LSQM-Laboratory of Chemical Synthesis of Materials-Department of Materials engineering Federal University of Rio Grande Do NorteP.O.Box 152459078-900Natal RNBrazil IFSC USPAv.Trabalhador Sao Carlense400CEP 13566-590Sao CarlosSPBrazil CDMF-LIeC UFSCarP.O.Box 67613565-905Sao Carlos.SPBrazil

CaWO_(4):xeu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(MAH).The phase formation,morphology,luminescent properties and ene rgy transfer were *** X-ray diffraction(XRD)re sults show the formation of a scheelitelike tetragonal structure without the presence of secondary *** growth mechanism of hierarchical micro structures based on self-assembly and Ostwald-ripening processes was evaluated,obtaining different types of *** luminescence spectra of CaWO_(4):eu^(3+),Tm^(3+)at 325 nm excitation show the predominance of red emission at the 5 D0→7 F2(eu^(3+))transition at 624 *** feature signals dominant behavior of the electric dipole *** presence of Tm^(3+)is notably evident in the absorption spectra by the related excitation transitions:3 H6→1 G4,3 H6→3 F3 and 3 H6→3 *** parameters are discussed to characterize CaWO_(4):eu^(3+),Tm^(3+)*** study of the emission spectrum as a function of the concentration of eu^(3+)(x mol%)and Tm^(3+)(y mol%)indicates that the CaWO_(4):eu^(3+),Tm^(3+)phosphors show stronger red emission intensity and exhibit the CIe value of x=0.63 and y=*** photoluminescence results show 97%high color purity for CaWO_(4):4 mol%eu^(3+),a high CRI(92%)and a low CCT of 1085 *** results demonstrate that the CaWO_(4):eu^(3+),Tm^(3+)red phosphors are promising as color converters for application in white light-emitting diodes and display devices.

关键词： CaWO_(4):eu^(3+),Tm^(3+)microwave-assisted hydrothermal method Photoluminescence Red phosphor Rare earths

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effect of different starting materials on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)

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Journal of Advanced Ceramics 2015年第1期4卷 65-70页

作者： P.N.MeDeIROS V.D.ARAÚJO A.P.A.MARQUeS R.L.TRANQUILIN C.A.PASKOCIMAS M.R.D.BOMIO J.A.VAReLA e.longo F.V.MOTTA DeMAT CTUFRNAv.Sen.Salgado Filho3000CEP 59072-970 NatalRNBrazil UACSA UFRPEBR 101 Sul5225CEP 54510-000 Cabo de Santo AgostinhoPEBrazil UNIFeSP Rua Prof.Artur Riedel275CEP 09972-270 DiademaSPBrazil dLIECIQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazil LIeC IQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazi

Literature has reported the synthesis of barium calcium titanates by various synthesis methods such as solid state reaction,co-precipitation and polymer *** compounds are usually obtained using calcium carbonate(CaCO_(3)),barium carbonate(BaCO3)and titanium oxide as starting *** study investigated the effect of different starting reagents on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)(BCT)by complex polymerization method(CPM).Two sets of starting precursors were used:titanium citrate,CaCO_(3)and BaCO3,and titanium citrate and Ba1-xCaxCO3 solid solution *** were crystallized at a temperature range from 400℃to 700℃for different *** obtained powders were characterized by X-ray diffraction(XRD),thermogravimetry(TG)and differential thermal analysis(DTA),and Raman and infrared *** infrared spectroscopy indicated that the chelation processes of Ba,Ca,Ti and CA ions are very *** results showed that the use of CaCO_(3)and BaCO3 or Ba1-xCaxCO3 solid solution as precursors does not affect the final properties of BCT powders obtained by CPM.

关键词： ceramic synthesis Ba_(0.8)Ca_(0.2)TiO_(3)(BCT) complex polymerization method(CPM)

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Update in management of mesenteric ischemia

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World Journal of Gastroenterology 2006年第20期12卷 3243-3247页

作者： Robert W Chang John B Chang walte. e.longo Professor Department of Surgery Yale University School of Medicine333 Cedar StreetNew Haven 06510United States

Mesenteric ischemia disorders are precipitated by a circulation insufficiency event that deprives one or several abdominal organs of adequate respiration to meet metabolic demands. Although mesenteric ischemia occurs infrequently, the mortality rate is from 60% to 100%, depending on the source of obstruction. The successful outcome is dependent upon a high index of suspicion and prompt management. We briefly review the pathophysiology and presentation of the various ischemic entities and review the current state of the art in diagnosis and treatment. Despite advances in both diagnosis and treatment, prompt diagnosis and supportive care remain critical for successful outcome. New imaging techniques, endovascular therapy and emerging research may improve our approach to this deadly condition.

关键词： Mesenteric ischemia Duplex ultrasonography Plasma D-dimer Computed tomography

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Management of parastomal ulcers

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World Journal of Gastroenterology 2006年第20期12卷 3133-3137页

作者： Heather Yeo Farshad Abir walte. e.longo Department of Surgery Yale University School of Medicine United States

Management of surgically placed ostomies is an important aspect of any general surgical or colon and rectal surgery practice. Complications with surgically placed ostomies are common and their causes are multifactorial. Parastomal ulceration, although rare, is a particularly difficult management problem. We conducted a literature search using MD Consult, Science Direct, OVID, Medline, and Cochrane Databases to review the causes and management options of parastomal ulceration. Both the etiology and treatments are varied. Different physicians and ostomy specialists have used a large array of methods to manage parastomal ulcers; these including local wound care; steroid creams; systemic steroids; and, when conservative measures fail, surgery. Most patients with parastomal ulcers who do not have associated IBD or peristomal pyoderma gangrenosum （PPG） often respond quickly to local wound care and conservative management. Patients with PPG, IBD, or other systemic causes of their ulceration need both systemic and local care and are more likely to need long term treatment and possibly surgical revision of the ostomy. The treatment is complicated, but improved with the help of ostomy specialists.

关键词： Parastomal ulcers Peristomal ulcers Ostomies Complications

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Asymptomatic ileal adenocarcinoma in the setting of undiagnosed Crohn's disease

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World Journal of Gastroenterology 2008年第29期14卷 4690-4693页

作者： Vikram B Reddy Harold Aslanian Namsoo Suh walte. e.longo Department of Surgery Yale University School of MedicineNew Haven Connecticut 06510 United States Department of Gastroenterology Yale University School of MedicineNew Haven Connecticut 06510 United States Department of Pathology Yale University School of MedicineNew Haven Connecticut 06510 United States

A 53-year old previously healthy male underwent a screening colonoscopy for detection of a potential colorectal neoplasm. The terminal ileum was intubated and a mass was noted. examination of the colon was normal. The biopsy of the ileal mass was consistent with an adenocarcinoma arising from the terminal ileum. His father who had never been previously ill from gastrointestinal disease died of natural causes, but was found to have Crohn's disease postmortem. The patient underwent exploratory laparotomy and a right hemicolectomy with a 30 cm section of terminal ileum in continuity. Findings were consistent with ileal adenocarcinoma in the setting of Crohn's disease. The patient made an uneventful recovery. The pathology was stage 1 adenocarcinoma. This is a unique case in that on a screening colonoscopy, a favorable ileal adenocarcinoma was discovered in the setting of asymptomatic, undiagnosed ileal Crohn's disease in a patient whose father had Crohn's disease diagnosed postmortem.

关键词： Ileal adenocarcinoma Crohn's disease Colonoscopy

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NeCAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael K.e.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal eF-hand calcium-binding proteins 1–3(NeCAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one eF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NeCAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NeCAB2 interacts with predominantly striatal G-protein-coupled receptors, while NeCAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NeCAB proteins exhibit distinct subcellular localizations: NeCAB1 is found in the nucleus and cytosol, NeCAB2 resides in endosomes and the plasma membrane, and NeCAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NeCAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NeCAB proteins by controlling the availability of protein–protein interaction domains situated between the eF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium eF hand mitochondria nervous system signal transduction

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Probiotics to counteract biofilm-associated infections: promising and conflicting data

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International Journal of Oral Science 2014年第4期6卷 189-194页

作者： Claudia Vuotto Francesca longo Gianfranco Donelli Microbial Biofilm Laboratory IRCCS Fondazione Santa Lucia Rome Italy

Altered bowel flora is currently thought to play a role in a variety of disease conditions, and the use of Bifidobacterium spp. and Lactobacillus spp. as probiotics has been demonstrated to be health-promoting, even if the success of their administration depends on the applied bacterial strain（s） and the targeted disease. In the last few decades, specific probiotics have been shown to be effective in the treatment or the prevention of acute viral gastroenteritis, pediatric post-antibiotic-associated diarrhea, some pediatric allergic disorders, necrotizing enterocolitis in preterm infants, inflammatory bowel diseases and postsurgical pouchitis. The potential application of probiotics is continuously widening, with new evidence accumulating to support their effect on the prevention and treatment of other disease conditions, including several oral diseases, such as dental caries, periodontal diseases and oral malodor, as well as genitourinary and wound infections. Considering the increasingly widespread ability of pathogens to generate persistent biofilm-related infections, an even more attractive proposal is to administer probiotics to prevent or counteract biofilm *** response of biofilm-based oral, intestinal, vaginal and wound infections to probiotics treatment will be reviewed here in light of the most recent results obtained in this field.

关键词： biofilm genitourinary tract gut infections oral cavity probiotics wounds

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Sexually transmitted infections of the anus and rectum

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World Journal of Gastroenterology 2014年第41期20卷 15262-15268页

作者： Roland Assi Peter W Hashim Vikram B Reddy Hulda einarsdottir walte. e.longo Department of Surgery Yale University School of Medicine

Sexually transmitted infections(STIs) represent a significant public health *** STIs,once thought to be on the verge of extinction,have recently *** change is thought to be partially related to an increase in STIs of the anus and ***,the global human immunodeficiency virus and acquired immunodeficiency syndrome(HIV/AIDS) epidemic has contributed to the emergence of particular anorectal lesions that require specialized *** this report,we review common anorectal STIs that are frequently referred to colorectal surgeons in the United ***,clinical presentation,and management are summarized,including the latest treatment *** particularity of anorectal diseases in HIV/AIDS is addressed,along with recent trends in anal cytology and human papillomavirus vaccination.

关键词： Sexually transmitted disease Rectal disease Sexual behavior Human papillomavirus Human immunodeficiency virus Perianal disease Highly active antiretroviral therapy Human papilloma virus vaccines Anal cytology

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Mayombian ethnic,vegetables low intake,insulin treatment,diabetic nephropathy and severe diabetic retinopathy are determinants of blindness in diabetic Africans

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International Journal of Ophthalmology(english edition) 2013年第5期6卷 727-732页

作者： Mvitu Muaka Moise.longo-Mbenza Benjamin Cibanda Yokobo enoch longo Phemba Igor Department of Ophthalmology Faculty of MedicineUniversity of Kinshasa walte. Sisulu University Faculty of Health Sciences Department of Anaesthesiology Nelson Mandela Academic Hospital School of International Studies Wenzhou Medical College

AIMTo determine the frequency and causes of blindness in diabetic Africans.

关键词： diabetes mellitus blindness ethnicity Mayombe diabetic retinopathy insulin treatment Africans

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