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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 11-19页

作者： Nathalia Vieceli carlos A.Nogueira manuel f.c.pereira fernando O.Durao carlos Guimaraes fernanda Margarido center for Innovation Technology and Po icy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laborat6rio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal cERENA-centro de Recursos Naturais e Ambiente DECivilInstituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal

The recovery of lithium from hard rock minerals has received increased attention given the high demand for this element. There- fore, this study optimized an innovative process, which does not require a high-temperature calcination step, for lithium extraction from le- pidolite. Mechanical activation and acid digestion were suggested as crucial process parameters, and experimental design and re- sponse-surface methodology were applied to model and optimize the proposed lithium extraction process. The promoting effect of amorphi- zation and the formation of lithium sulfate hydrate on lithium extraction yield were assessed. Several factor combinations led to extraction yields that exceeded 90%, indicating that the proposed process is an effective approach for lithium recovery.

关键词： lepidolite lithium mechanical activation acid digestion optimization extraction

Kinetic approach to the study of froth flotation applied to a lepidolite ore

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 731-742页

作者： Nathália Vieceli fernando O.Durao carlos Guimaraes carlos A.Nogueira manuel f.c.pereira fernanda Margarido center for Innovation Technology and Policy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal cERENA-centro de Recursos Naturais e Ambiente DECivilInstituto Superior TecnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laboratorio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal

The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp p H values, and estimate a near-optimum flotation time. Both collectors（Aeromine 3000 c and Armeen 12D） provided the required flotation selectivity, although this selectivity was lost in the case of pulp p H values outside the range between 2 and 4. cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation efficiency（SE） function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval required to achieve 95%–99% of the maximum value of the SE function.

关键词： lepidolite lithium ore treatment froth flotation kinetic analysis

Micro-computed tomography assessment of human femoral trabecular bone for two disease groups(fragility fracture and coxarthrosis):Age and gender related effects on the microstructure

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Journal of Biomedical Science and Engineering 2013年第2期6卷 175-184页

作者： Ana catarina Vale manuel f.c.pereira Antonio Maurício Bruno Vidal Ana Rodrigues Joana caetano-Lopes Ara Nazarian Joao E.fonseca Helena canhao Maria fatima Vaz Institute of Materials and Surface Science and Engineering LisbonPortugal Rheumatology Research Unit Instituto de Medicina MolecularFaculdade de Medicina de LisboaLisbonPortugal center of Petrology and Geochemistry Instituto Superior TécnicoUniversidade Técnica de LisboaLisbonPortugal Rheumatology and Metabolic Bone Diseases Department Hospital de Santa MariaLisbonPortugal Orthopedic Biomechanics Laboratory Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonUSA Mechanical Engineering Department Instituto Superior TecnicoUniversidade Tecnica de LisboaLisbonPortugal

The aim of this study was to identify three-dimensional microstructural changes of trabecular bone with age and gender, using micro-computed tomography. Human trabecular bone from two disease groups, osteoporosis and osteoarthritis was analyzed. A prior analysis of the effects of some procedure variables on the micro-cT results was performed. Preliminary micro-cT scans were performed with three voxel resolutions and two acquisition conditions. On the reconstruction step, the image segmentation was performed with three different threshold values. Samples were collected from patients, with coxarthrosis (osteoarthritis) or fragility fracture (osteoporosis). The specimens of the coxarthrosis group include twenty females and fifteen males, while the fragility fracture group was composed by twenty three females and seven males. The mean age of the population was 69 ± 11 (females) and 67 ± 10 years (males), in the coxarthrosis group, while in the fragility fracture group was 81 ± 6 (females) and 78 ± 6 (males) years. The 30 μm voxel size provided lower percentage difference for the microarchitecture parameters. Acquisition conditions with 160 μA and 60 kV permit the evaluation of all the volume’s sample, with low average values of the coefficients of variation of the microstructural parameters. No statistically significant differences were found between the two diseases groups, neither between genders. However, with aging, there is a decrease of bone volume fraction, trabecular number and fractal dimension, and an increase of structural model index and trabecular separation, for both disease groups and genders. The parameters bone specific surface, trabecular thickness and degree of anisotropy have different behaviors with age, depending on the type of disease. While in coxarthrosis patients, trabecular thickness increases with age, in the fragility fracture group, there is a decrease of trabecular thickness with increasing age. Our findings indicate that disease, age and gender do not provide significant differences in

关键词： Trabecular Bone Micro-computed Tomography coxarthrosis fragility fracture Age Gender

carbon Monoxide as c1 Building Block in fine chemical Synthesis

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chinese Journal of chemistry 2024年第2期42卷 199-221页

作者： Rui M.B.carrilho Mario J.f.calvete Gabor Mikle Laszlo Kollar Mariette M.pereira University of coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic chemistry and ELKH-PTE Research Groupfor Selective chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

carbon monoxide(cO)has become one of the most relevant and versatile renewable c1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its activation.In this review,we present a comprehensive critical analysis of the last 10 years literature on the use of cO as a renewable feedstock for fine chemicals production.The review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and c-H carbonylation.Notable examples of the synthesis of relevant building blocks and/or known pharmaceuticals are highlighted.Emphasis is placed on examples of utilizing cO as the c1 building block in one or more catalytic steps.The catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： carbon monoxide fine chemicals carbonylation Hydroformylation c-H functionalization

Prognosis value of heat-shock proteins in esophageal and esophagogastric cancer:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1578-1595页

作者： Eric Toshiyuki Nakamura Amanda Park Marina Alessandra pereira Daniel Kikawa francisco Tustumi Department of Gastroenterology Instituto do CâncerHospital das Clínicas da Universidade de São PauloFaculdade de MedicinaUniversidade de São PauloSão Paulo 01246000Brazil Department of Scientific Initiation Universidade Mogi das CruzesSão Paulo 08780911Brazil Department of Evidence-Based Medicine Centro Universitário LusíadaCentre for Evidence-Based MedicineCentro Universitário Lusíada(UNILUS)SantosBrazil Department of Surgery Hospital Israelita Albert EinsteinSão Paulo 05652900Brazil

BAcKGROUND Heat shock proteins(HSPs)are molecular chaperones that play an important role in cellular protection against stress events and have been reported to be overex-pressed in many cancers.The prognostic significance of HSPs and their regulatory factors,such as heat shock factor 1(HSf1)and cHIP,are poorly understood.AIM To investigate the relationship between HSP expression and prognosis in esophageal and esophagogastric cancer.METHODS A systematic review was conducted in accordance with PRISMA recommend-ations(PROSPERO:cRD42022370653),on Embase,PubMed,cochrane,and LILAcS.cohort,case-control,and cross-sectional studies of patients with eso-phagus or esophagogastric cancer were included.HSP-positive patients were compared with HSP-negative,and the endpoints analyzed were lymph node metastasis,tumor depth,distant metastasis,and overall survival(OS).HSPs were stratified according to the HSP family,and the summary risk difference(RD)was calculated using a random-effect model.RESULTS The final selection comprised 27 studies,including esophageal squamous cell carcinoma(21),esophagogastric adenocarcinoma(5),and mixed neoplasms(1).The pooled sample size was 3465 patients.HSP40 and 60 were associated with a higher 3-year OS[HSP40:RD=0.22;95%confidence interval(cI):0.09-0.35;HSP60:RD=0.33;95%cI:0.17-0.50],while HSf1 was associated with a poor 3-year OS(RD=-0.22;95%cI:-0.32 to-0.12).The other HSP families were not associated with long-term survival.HSf1 was associated with a higher probability of lymph node metastasis(RD=-0.16;95%cI:-0.29 to-0.04).HSP40 was associated with a lower probability of lymph node dissemination(RD=0.18;95%cI:0.03-0.33).The expression of other HSP families was not significantly related to tumor depth and lymph node or distant metastasis.cONcLUSION The expression levels of certain families of HSP,such as HSP40 and 60 and HSf1,are associated with long-term survival and lymph node dissemination in patients with esophageal and esophagogastric cancer.

关键词： Heat-shock proteins Heat-shock response Prognosis Esophageal neoplasms Meta-analysis

The effect of abiotic stresses on plant c:N:P homeostasis and their mitigation by silicon

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The crop Journal 2024年第2期12卷 340-353页

作者： Milton Garcia costa Renato de Mello Prado Luiz fabiano Palaretti Jonas pereira de Souza Júnior Department of Agricultural Production Science School of Agricultural and Veterinarian SciencesSão Paulo State UniversityJaboticabalBrazil

In crop plants, various environmental stresses affect the balance of carbon, nitrogen, and phosphorus(c:N:P), leading to biochemical and physiological alterations and reductions in yield. Silicon(Si) is a beneficial element that alleviates plant stress. Most studies involving silicon have focused on physiological responses, such as improvements in photosynthetic processes, water use efficiency, and antioxidant defense systems. But recent research suggests that stressed plants facing either limited or excessive resources(water, light, nutrients, and toxic elements), strategically employ Si to maintain c:N:P homeostasis, thereby minimizing biomass losses. Understanding the role of Si in mitigating the impact of abiotic stresses on plants by regulating c:N:P homeostasis holds great potential for advancing sustainable agricultural practices in crop production. This review presents recent advances in characterizing the influence of environmental stresses on c:N:P homeostasis, as well as the role of Si in preserving c:N:P equilibrium and attenuating biological damage associated with abiotic stress. It underscores the beneficial effects of Si in sustaining c:N:P homeostasis and increasing yield via improved nutritional efficiency and stress mitigation.

关键词： Nutritional stoichiometry Elemental stoichiometry Beneficial element Environmental stresses Nutritional efficiency carbon use efficiency Agricultural sustainability

Preclinical and clinical evidence of the association of colibactinproducing Escherichia coli with anxiety and depression in colon cancer

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World Journal of Gastroenterology 2024年第21期30卷 2817-2826页

作者： fabien Rondepierre Maëva Meynier Johan Gagniere Vincent Deneuvy Anissa Deneuvy Gwenaelle Roche Elodie Baudu Bruno pereira Richard Bonnet Nicolas Barnich frédéric Antonio carvalho Denis Pezet Mathilde Bonnet Isabelle Jalenques Service de Psychiatrie de l’Adulte A et Psychologie Médicale CHU Clermont-FerrandClermont-Ferrand 63000France M2iSH UMR 1071INSERMUniversity of Clermont AuvergneINRAE USC 1382Clermont-Ferrand 63001France NeuroDol UMR 1107INSERMUniversity of Clermont AuvergneClermont-Ferrand 63001France Department of Digestive Surgery CHU de Clermont-FerrandClermont-Ferrand 63001France Biostatistics Unit Department of Clinical Research and InnovationCHU Clermont-FerrandClermont-Ferrand 63000France Department of Bacteriology CHU de Clermont-FerrandClermont-Ferrand 63001France Universitéclermont Auvergne INPCNRSClermont Auvergne Institut PascalClermont-Ferrand 63000France

BAcKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The gut microbiota contributes to colorectal carcinogenesis(cRc),as demonstrated with colibactin-producing Escherichia coli(coPEc).AIM To evaluate the association between coPEc prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical approaches.METHODS Patients followed after a cRc surgery and for whom the prevalence of coPEc has been investigated underwent a psychiatric interview.Results were compared according to the coPEc colonization.In parallel c57BL6/J wild type mice and mice with a cRc susceptibility were chronically infected with a coPEc strain.Their behavior was assessed using the Elevated Plus Maze test,the forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with coPEc colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without coPEc did.This result was confirmed in c57BL6/J wildtype mice and in a cRc susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a coPEc strain.cONcLUSION This finding provides the first evidence that coPEc infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.

关键词： colorectal cancer colibactin Escherichia coli colibactin-producing Escherichia coli Inflammation Anxiety Depression Behavior

Bioremediation Potential of the Macroalga Ulva lactuca (chlorophyta) for Ammonium Removal in Elastomer Industry Wastewater

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Advances in Bioscience and Biotechnology 2024年第6期15卷 325-343页

作者： Diego Lelis Alex Enrich-Prast camille R. chaves Thuane Mendes Anacleto Roberta R. c. pereira Vinicius P. de Oliveira Programa de Ps-Graduao em Biotecnologia Vegetal e Bioprocessos Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Unidade Multiusurio de Anlises Ambientais Universidade Federal do Rio de Janeiro Rio de Janeiro Brazil Institute of Marine Science Federal University of So Paulo (IMar/UNIFESP) Santos Brazil Department of Thematic StudiesEnvironmental change and Biogas Solutions Research center (BSRc) Linkping University Linkping Sweden Department of Marine Biology Institute of Biology Federal University of Rio de Janeiro Rio de Janeiro Brazil

During the production of nitrile rubber, significant amounts of nitrogen in the form of ammonium are generated in the wastewater. The discharge of this high-nitrogen wastewater can lead to serious environmental issues, including eutrophication, disruption of aquatic ecosystems, and groundwater contamination. To mitigate these impacts, this research explored the bioremediation capabilities of the macroalgae Ulva lactuca (chlorophyta) for removing nitrogen from nitrile rubber production wastewater. The study employed single-phase and Michaelis-Menten decay models based on ammonium consumption, using various dilutions of wastewater to identify the optimal concentration for treatment. The physiological state of the macroalgae was monitored by measuring the photosynthetic capacity and specific growth rate during the experiments. In the presence of U. lactuca, ammonium concentrations decreased in all treatment groups, confirming that the ammonium kinetics conformed to both applied models. Our results show that U. lactuca effectively reduces ammonium concentrations, with an approximate removal rate of 0.020 µM·g−1·min−1 across different wastewater concentrations (70%, 80%, 90%, and 100%). Notably, the treatments with 70%, 80%, and 90% wastewater strength achieved about 67% reduction in ammonium, demonstrating the alga’s capacity to treat high-nitrogen wastewater. The photosynthetic performance of U. lactuca initially declined in control conditions but stabilized across all treatments, highlighting its adaptability. The kinetic analysis using the Michaelis-Menten model indicated a Vmax of 1342 μM·g−1·DMh−1, suggesting a robust capacity for ammonium uptake when fully saturated. Our study underscores the potential of Ulva lactuca as a cost-effective and efficient agent for wastewater bioremediation, particularly in settings with high nitrogen loads.

关键词： Photosynthetic Quantum Yield One-Phase Decay Model Michaelis-Menten Model Nitrogen Physiological Parameters Elastomers

clinical/Behavioral Monitoring of Rodents and Rabbits Undergoing Scientific Experiments

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Open Journal of Veterinary Medicine 2024年第5期14卷 91-109页

作者： Luiz cesar cavalcanti pereira Jhônata Willy Rocha coelho Hyago da Silva Medeiros Elidio Rita de cássia dos Passos ferraz Da Silva João Gabriel Regis Sobral Bárbara Alves de Brito Soledade Leandro Thomaz Vilela Isabele Barbieri Dos Santos Institute of Science and Technology in Biomodels (IcTB) Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Brazil Laboratory Animal facility of the carlos chagas Pavilion of the Animal Experimentation center (cEA) Oswaldo Cruz Institute (IOC) Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Brazil

Background: We currently have international and national guidelines regarding the assessment and monitoring of clinical signs and humane endpoints in animals used in teaching and research, which make the performance of these activities mandatory for any experiment and professional working in this area. Assigning the severity of a research experiment is the result of an analysis of records of observations of the animal’s behavior, and clinical signs. The aim of this study was to describe the importance of carrying out a severity assessment associated with clinical and behavioral monitoring of rodents and rabbits during experimentation to maintain the welfare of these animals undergoing scientific research. Methods: The literature search was carried out using the following terms: “Monitoring”;“Humane endpoints”;“Animal welfare”, “Rodents”;“Rabbits”, and as connectors “and”;“or”, in the following databases: PubMed;LILAcS/BIREME and SciELO. Results: A total of 987 articles were identified in the databases, and 20 of these studies were included in this review. conclusions: Humane endpoint protocols and procedure severity tables are of the utmost importance, both from an ethical point and to refine the results of research conducted on laboratory animals. They should be drawn up jointly by the teams responsible for the project and the maintenance of the animals during the research period, and the data obtained should be published so that the scientific community can have access to it, helping to disseminate these practices, as well as helping to draw up new procedures. Monitoring and evaluating the welfare and clinical condition of animals undergoing scientific research procedures is the responsibility of the professors, researchers, veterinarians, and animal facility coordinators. The Ethics committee on the Use of Animals must monitor all the activities conducted with the animals, by inspecting the experimental procedures and the physical environment of the laboratory animal facility where the animals are housed.

关键词： Monitoring Humane Endpoints Animal Welfare Experimental Design Laboratory Animals’ Investigations

The effect of fatigue and duration knowledge of exercise on kicking performance in soccer players

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Journal of Sport and Health Science 2019年第6期8卷 567-573页

作者： Ricardo manuel Pires ferraz Roland van den Tillaar Ana pereira Mario c.Marques Department of Sports Sciences University of Beira InteriorCovilha 6201-001Portugal Research center in Sports Sciences Health and Human DevelopmentCIDESDVila Real 5000-801Portugal Department of Teacher Education of Nord University Levanger 7600Norway Department of Technology and Science School of Education of Polytechnic Institute of SetubalSetubal 2910-761Portugal

Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the exercise duration upon these 2 parameters.Methods:Twenty-four semi-professional soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol,either with or without knowledge of the duration of this protocol.Results:A mixed model of analysis of variance showed that kicking maximal ball velocity was significantly affected(f(5,85)=11.6,pfter just 1 circuit of the fatigue protocol and then remained similar.Accuracy did not change during the protocol(f(5,75)=0.23,p=0.76,η^2=0.03) and knowing the duration of exercitation did not affect accuracy and velocity development(f(1,23) ≤1.04,p≥0.32,η~2≤0.06).conclusion:These findings demonstrated the potential negative effects of fatigue on kicking ball velocity in soccer but not in the kicking accuracy and that the effect of fatigue may not be progressive over time.Knowing or not knowing the duration of exercitation did not affect the results.

关键词： fatigue Kicking ball velocity Pacing Perception of effort Self-regulation of effort