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Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra Carvalho ana Sofia Ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr *** analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 GPa across all ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%*** testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%*** with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/*** synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequentl

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

Urea breath test for Helicobacter pylori infection in adult dyspeptic patients: A meta-analysis of diagnostic test accuracy

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World Journal of Gastroenterology 2024年第6期30卷 579-598页

作者： Fabian Fellipe Bueno Lemos Caroline Tianeze de Castro Marcel Silva Luz Gabriel reis Rocha Gabriel Lima Correa Santos Luís Guilherme de Oliveira Silva Mariana Santos Calmon Cláudio Lima Souza ana Carla Zarpelon-Schutz Kádima Nayara Teixeira Dulciene Maria de Magalhães Queiroz Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil Instituto de Saúde Coletiva Universidade Federal da BahiaSalvador 40110040BahiaBrazil Campus Toledo Universidade Federal do ParanáToledo 85919-899ParanáBrazil Laboratory of Research in Bacteriology UFMGBelo Horizonte 30130-100Minas GeraisBrazil

BACKGROUND Helicobacter pylori(***)infection has been well-established as a significant risk factor for several gastrointestinal *** urea breath test(UBT)has emerged as a leading non-invasive method for detecting *** numerous studies confirming its substantial accuracy,the reliability of UBT results is often compromised by inherent *** findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of *** *** To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for *** infection in adult patients with *** We conducted an independent search of the PubMed/MEDLINE,EMBASE,and Cochrane Central databases until April *** search included diagnostic accuracy studies that evaluated at least one of the index tests(^(13)C-UBT or ^(14)C-UBT)against a reference *** used the QUADAS-2 tool to assess the methodo-logical quality of the *** utilized the bivariate random-effects model to calculate sensitivity,specificity,positive and negative test likelihood ratios(LR+and LR-),as well as the diagnostic odds ratio(DOR),and their 95%confidence *** conducted subgroup analyses based on urea dosing,time after urea administration,and assessment *** investigate a possible threshold effect,we conducted Spearman correlation analysis,and we generated summary receiver operating characteristic(SROC)curves to assess ***,we visually inspected a funnel plot and used Egger’s test to evaluate publication *** both as reliable diagnostic tools in clinical *** In summary,our study has demonstrated that ^(13)C-UBT has been found to outperform the ^(14)C-UBT,making it the preferred diagnostic ***,our results emphasize the significance of carefully considering urea dosage,assessment timing,and measurement techniques for both tests to enh

关键词： Helicobacter pylori Urea breath test Diagnosis Diagnostic test accuracy Meta-analysis

How do greenhouse gas emissions vary with biofertilizer type and soil temperature and moisture in a tropical grassland?

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Pedosphere 2020年第5期30卷 607-617页

作者： Abmael da Silva CARDOSO Juliana Bega JUNQUEIRA Ricardo Andrade reis ana Claudia RUGGIERIAnimal Science Departament College of Agricultural and Veterinarian SciencesSao Paulo State UniversityJaboticabal 14884-900(Brazil) Kenji Agricultural and Environmental Consultancy Ribeirdo Preto 14010-079(Brazil)

Greenhouse gases are known to play an important role in global *** this study,we determined the effects of selected soil and climate variables on nitrous oxide(N2O),methane(CH4),and carbon dioxide(CO2)emissions from a tropical grassland fertilized with chicken slurry,swine slurry,cattle slurry,and cattle *** N2O emissions did not differ between treatments and varied from 29.26 to 32.85 mg N m^-***,cumulative CH4 emissions were not significantly different among the treatments and ranged from 6.34 to 57.73 mg CH4 m^-*** and compost application induced CO2 emissions that were significantly different from those in the control *** CH4 conversion factors measured were 0.21%,1.39%,4.39%,and 5.07%for cattle compost,chicken slurry,swine slurry,and cattle slurry,respectively,differing from the recommendations of the Intergovernmental Panel on Climate Change(IPCC).The fraction of added Nemitted as N2O was 0.39%,which was lower than the IPCC default value of 2%.Our findings suggest that N2O emissions could be mitigated by replacing synthetic fertilizer sources with either biofertilizer or *** results indicate the following:N2O emission was mainly controlled by soil temperature,followed by soil moisture and then soil NH^"content;CH4 fluxes were mainly controlled by soil moisture and chamber headspace temperature;and CO2 fluxes were mainly controlled by chamber headspace temperature and soil moisture.

关键词： emission factor methane conversion factor methane oxidation methane production capacity slurry fertilizer soil moisture

An Outlook on Implantable Biosensors for Personalized Medicine

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Engineering 2021年第12期7卷 1696-1699页

作者： Rita Rebelo ana Isabel Barbosa Vitor M.Correlo Rui L.reis Research Institute on Biomaterials Biodegradablesand BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineBarcoGuimarães 4805-017Portugal ICVS/3B’s-PT Government-Associated Laboratory BragaGuimarães 4710-057Portugal

Biosensors are a fast-growing field,as they have been shown to be very helpful in our daily life,playing roles in industries such as agriculture,food safety,homeland security,bioprocessing,environmental monitoring,and industrial *** these,the application of biosensing in medicine and biomedical engineering may have the highest potential for growth and for affecting human quality of life in the near *** potential is driven by the need for new and improved devices and technologies with improved sensitivity,specificity,reliability,and biocompatibility.

关键词： Outlook specificity playing

^(222)Rn calibration procedure for water analyses by liquid scintillation counting

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辐射探测技术与方法(英文) 2023年第2期7卷 311-319页

作者： ana Rita Gomes Sérgio Dias anabela Mourato Joao Abrantes Mário reis Laboratório de Protecao e Seguranca Radiológica Instituto Superior TécnicoUniversidade de LisboaEstrada Nacional 10km 13972695‑066 Bobadela LRSPortugal Laboratórios de Massa e Massa Volúmica de Sólidos Instituto Portugues da QualidadeRua António Giao22829‑513 CaparicaPortugal Centro de Ciências e Tecnologias Nucleares Instituto Superior TécnicoUniversidade de LisboaEstrada Nacional 10km 13972695‑066 Bobadela LRSPortugal

Purpose Among the several methods to measure ^(222)Rn in water,the liquid scintillation counting(LSC)technique is one of the most sensitive and widely used when analysing non-saline waters by liquid extraction,providing excellent accuracy,precision and low-level detection *** using the liquid scintillation counter Tri-Carb 3170 TR/SL(Perkin-Elmer)it is not possible to make an automatic determination of the alpha/beta discrimination parameter,being necessary to evaluate the pulse decay discriminator(PDD)value manually to the ^(222)Rn *** this work,we describe the steps to perform the calibration of that type of *** The method consists in the preparation of standard samples from a ^(226)Ra certified standard solution and the adjustment of the PDD value by hand until the percentage of alpha events reaches a plateau of a near-constant fraction of total *** process consists in taking several measures between PDD 80 and 200 with 15 min counting time *** the plateau,the alpha/beta ratio was used to determine the plateau final range as well as the optimum PDD *** that,the calibration standards and blanks were measured and the region of interest(ROI)was established by finding the maximum value for the figure of merit(FOM)in the upper and lower *** The optimal PDD value of 148 was established by the alpha/beta ratio,and after that,it was possible to measure ^(226)Ra standards to perform the *** efficiency of(9.758±0.035)×1^(0-1) was *** routine measurements,a detection limit of about 0.50 Bq L^(-1) is achieved for a 120 min counting *** evaluate the uncertainty budget,the uncertainties of the net count rate,the efficiency,the sample amount and the decay correction factor were *** A method was developed for the calibration of LSC Tri-Carb 3170 TR/SL with the optimization of the PDD using a ^(226)Ra standard *** acquisition to obtain the plot of the variation

关键词： Radon Waters Pulse decay discriminator Liquid scintillation counting Calibration

Cirrhosis in children and adolescents: An overview

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World Journal of Hepatology 2015年第3期7卷 392-405页

作者： Raquel Borges Pinto ana Claudia reis Schneider Themis Reverbel da Silveira Pediatric Gastroenterology Unit Hospital da Crianca Conceicao Porto Alegre 91340 480 Rio Grande do Sul Brazil Post-Graduate Program in Gastroenterology and Hepatology Universidade Federal do Rio Grande do Sul Porto Alegre RS 90040-060 Brazil.

Several conditions, especially chronic liver diseases, can lead to cirrhosis in children and adolescents. Most cases in clinical practice are caused by similar etiologies. In infants, cirrhosis is most often caused by biliary atresia and genetic-metabolic diseases, while in older children, it tends to result from autoimmune hepatitis,Wilson's disease, alpha-1-antitrypsin deficiency and primary sclerosing cholangitis. The symptoms of cirrhosis in children and adolescents are similar to those of adults. However, in pediatric patients, the first sign of cirrhosis is often poor weight gain. The complications of pediatric cirrhosis are similar to those observed in adult patients, and include gastrointestinal bleeding caused by gastroesophageal varices, ascites and spontaneous bacterial peritonitis. In pediatric patients, special attention should be paid to the nutritional alterations caused by cirrhosis, since children and adolescents have higher nutritional requirements for growth and development. Children and adolescents with chronic cholestasis are at risk for several nutritional deficiencies. Malnutrition can have severe consequences for both pre- and post-liver transplant patients. The treatment of cirrhosis-induced portal hypertension in children and adolescents is mostly based on methods developed for adults. The present article will review the diagnostic and differential diagnostic aspects of end-stage liver disease in children, as well as the major treatment options for this condition.

关键词： Cirrhosis Liver diseases Nutrition Pediatric patients Portal hypertension

Association between EGF +61A/G polymorphism and gastric cancer in Caucasians

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World Journal of Gastroenterology 2011年第4期17卷 488-492页

作者： ana Paula Araújo Bruno M Costa ana L Pinto-Correia Maria Fragoso Paula Ferreira Mário Dinis-Ribeiro Sandra Costa Rui M reis Rui Medeiros Molecular Oncology Group Portuguese Institute of Oncology of Porto Life and Health Sciences Research Institute (ICVS) School of Health Sciences Oncology Department Portuguese Institute of Oncology of Porto Gastroenterology Department Portuguese Institute of Oncology of Porto Portugal Cintesis/Faculty of Medicine University of Porto Centro de Estudos em Biomedicina Health Sciences Faculty-Fernando Pessoa University Instituto de Ciencias Biomédicas de Abel Salazar Abel Salazar Institute for the Biomedical Sciences

AIM: To investigate the association between epidermal growth factor (EGF) +61A/G polymorphism and susceptibility to gastric cancer, through a cross-sectional study. METHODS: Polymerase chain reaction resctriction fragment lenght polymorphism analyses were used to genotype EGF +61 in 207 patients with gastric lesions (162 patients with gastric adenocarcinomas, 45 with atrophy or intestinal metaplasia) and 984 controls. All subjects were Caucasian. RESULTS: Genotype distribution was 23.5% for GG and 76.5% for GA/AA in the control group, 18.4% for GG and 68.6% for GA/AA in the entire group with gastric lesions and 17.9% for GG and 82.1% for GA/AA in the group with gastric adenocarcinoma. No statistically significant associations were found between EGF +61 variants and risk for developing gastric cancer [odds ratios (OR) = 1.41, 95% confidence intervals (CI): 0.90-2.21, P = 0.116]. However, the stratification of individuals by gender revealed that males carrying A alleles (EGF +61A/G or AA) had an increased risk for developing gastric cancer as compared to GG homozygous males (OR = 1.55, 95% CI: 1.05-2.28, P = 0.021). CONCLUSION: In summary, we found that males who were A carriers for EGF +61 had an increased risk for developing gastric cancer. This result may be explained by the suggestion that women secrete less gastric acid than men.

关键词： Epidermal growth factor polymorphism Epidermal growth factor receptor Gastric cancer

Changes in social emotion recognition following traumatic frontal lobe injury

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Neural Regeneration Research 2012年第2期7卷 101-108页

作者： ana Teresa Martins Luis Faísca Francisco Esteves Cláudia Simo Mariline Gomes Justo Angélica Muresan Alexandra reis Department of Psychology University of Algarve Lisbon Universitary Institute

Changes in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 age- and education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions （arrogance, guilt and jealousy）. Results suggested that ability to recognize two social emotions （arrogance and jealousy） was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location （right, left or bilateral） suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions.

关键词： traumatic brain injury facial emotion recognition social emotions

Interaction between cannabinoid and nucleotide systems as a new mechanism of signaling in retinal cell death

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Neural Regeneration Research 2019年第12期14卷 2093-2094页

作者： Hércules R. Freitas Ricardo A. M. reis ana L. M. Ventura Guilherme R. Franca Laboratory of Neurochemistry Institute of Biophysics Carlos Chagas Filho Universidade Federal do Rio de Janeiro Rio de Janeiro RJ Brazil School of Health Sciences Centro Universitário IBMR Rio de Janeiro RJ Brazil Laboratory of Neurochemistry Institute of Biology Universidade Federal Fluminense Niterói RJ Brazil Biomedical Institute Departament of Physiological Sciences/ Pharmacology Universidade Federal do Estado do Rio de Janeiro Rio de Janeiro RJ Brazil

Nervous system emerges from complex signaling interactions where extrinsic (neurotransmitters and trophic factors, among others) and intrinsic factors (transcription factors) interplay in the developing tissue to control gene activity promoting chronic changes in cell genesis, migration, differentiation and death. The retinal microenvironment is regulated by a broad variety of chemicals, including endocannabinoids and nucleotides that modulate embryonic progenitor-neuron-Müller glia signaling in very early developing or pathophysiological conditions.

关键词： Interaction nucleotide systems cell death