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Poly(Vinyl Alcohol)(PVAl)and Poly(N-2-Vinyl-Pyrrolidone)Hydrogels Nanostructured by Laponite Clay for Drug Delivery

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材料科学与工程（中英文b版） 2022年第3期12卷 97-107页

作者： Maria José.A.oliveira Vinicius J.Santos Lucas Freitas de Freitas ademar b.lugão Duclerc F.Parra Nuclear and Energy Research Institute-IPEN-CNEN/SP.Av.Professor Lineu Prestes 2242Cidade UniversitáriaSão Paulo 05508-000SPBrazil

Hydrogels for wound dressings are usually developed for contact surfaces where mechanical properties are conveniently *** this sense nanocomposite hydrogels based on PVAl(poly(vinyl alcohol))and PVP(poly(N-2-vinil-pirrolidone))containing 0.5-1.5 wt%of the synthetic laponite RD clay were prepared by a gamma radiation process and compared with similar membranes composed separately of PVP or *** study aimed to evaluate the effect of clay on the properties and the differences of the polymer blend instead of a unique *** morphology of the hydrogels was evaluated by spectrometric techniques using XRD(X-ray diffraction),SEM(scanning electron microscopy),swelling assay,and FTIR(infrared spectroscopy).The swelling kinetics at 22℃and the mechanical properties by a tensile test comprised the structural properties that were *** results showed PVA/PVP network depends directly on the clay concentration in the nanocomposite *** blend PVP/PVAl proved to have potentially efficient mechanical properties for drug delivery in the treatment of wounds.

关键词： Hydrogels clay nanocomposite drug delivery.

Green Nanotechnology from Plant Extracts: Synthesis and Characterization of Gold Nanoparticles

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Advances in Nanoparticles 2016年第3期5卷 176-185页

作者： Adriana Napoleão Geraldes Andressa Alves da Silva Jessica Leal Gethzemani Mayeli Estrada-Villegas Nilton Lincopan Kattesh V. Katti ademar benévolo lugão Centro de Química e Meio Ambiente Instituto de Pesquisas Energéticas e Nucleares-Comiss&atildeo Nacional de Energia Nuclear (IPEN-CNEN) S&atilde o Paulo Brazil Centro de Química e Meio Ambiente Instituto de Pesquisas Energéticas e Nucleares-Comiss&atildeo Nacional de Energia Nuclear (IPEN-CNEN) S&atildeo Paulo Brazil Laboratório de Resistência bacteriana & Alternativas Terapêuticas Instituto de Ciências Biomédicas S&atildeo Paulo Brazil Department of Radiology Physics Bio-Medical Sciences Nuclear Science and Engineering Institute University of Missouri-Columbia Columbia USA

The advantage of using plants in nanoparticles synthesis is that they are easily available, safe to handle and possess a broad variability of metabolites such as antioxidants, nucleotides and vitamins. The aim of this study was to investigate the effects of Green and Zimbro tea and also Green coconut water as a reducing and stabilizer agent in gold nanoparticle synthesis. The gold nanoparticles were characterized by UV-Vis absorption spectroscopy, X-ray diffraction (XRD), Dynamic light scattering (DLS) and Transmission electron microscopy (TEM) analysis. Their physical stability was determined using a UV-Vis spectrophotometer over several days during storage at room temperature. We observed that green chemical process to obtain gold nanoparticles did not require any external chemicals reagent for stabilization of nanoparticulate. Absorption measurements indicated that the plasmon resonance wavelength appears around 530 nm. X-ray diffracto-grams of gold nanoparticles evidenced the presence of Au-rich (fcc) phases. TEM analysis showed a homogeneous dispersion of nanoparticles and some agglomerates. Differences in size and shape of the nanoparticles were observed. Zeta potential of AuNPs synthetized in presence of Green tea was -33 mV indicating stability of the synthesized nanoparticles.

关键词： Green Nanotechnology Gold Nanoparticles Camellia sinensis Juniperus communis Green Coconut Water

A sensitive electrochemical detection of metronidazole in synthetic serum and urine samples using low-cost screen-printed electrodes modified with reduced graphene oxide and C60

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Journal of Pharmaceutical Analysis 2021年第5期11卷 646-652页

作者： Elsa Maria Materon ademar Wong Tayane Aguiar Freitas Ronaldo Censi Faria osvaldo N.oliveira Jr. Department of Chemistry Federal University of Sao Carlos13560-970Sao CarlosBrazil Sao Carlos Institute of Physics University of Sao Paulo13560-970Sao CarlosBrazil

Monitoring the concentration of antibiotics in body fluids is essential to optimizing the therapy and minimizing the risk of bacteria resistance,which can be made with electrochemical sensors tailored with appropriate *** this paper,we report on sensors made with screen-printed electrodes(SPE)coated with fullerene(C60),reduced graphene oxide(rGo)and Nafion(NF)(C60-rGo-NF/SPE)to determine the antibiotic metronidazole(MTZ).Under optimized conditions,the C60-rGo-NF/SPE sensor exhibited a linear response in square wave voltammetry for MTZ concentrations from 2.5×10^(-7) to 34×10^(-6) mol/L,with a detection limit of 2.1×10^(-7) mol/*** sensor was also capable of detecting MTZ in serum and urine,with recovery between 94%and 100%,which are similar to those of the standard chromatographic method(HPLC-UV).because the C60-rGo-NF/SPE sensor is amenable to mass production and allows for MTZ determination with simple principles of detection,it fulfills the requirements of therapeutic drug monitoring programs.

关键词： Metronidazole Fullerene Reduced graphene oxide Screen-printed electrodes Antibiotic

Repurposing metformin for the treatment of gastrointestinal cancer

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World Journal of Gastroenterology 2021年第17期27卷 1883-1904页

作者： ademar Dantas Cunha Júnior Arinilda Campos bragagnoli Felipe osório Costa Josébarreto Campello Carvalheira Department of Internal Medicine Division of OncologyUniversity of Campinas(UNICAMP)Campinas 13083-970São PauloBrazil Division of oncology Hospital de Câncer de BarretosBarretos 14784-400São PauloBrazil

Diabetes mellitus type 2 and cancer share many risk *** pleiotropic insulin-dependent and insulin-independent effects of metformin might inhibit pathways that are frequently amplified in neoplastic ***,modulation of inflammation,metabolism,and cell cycle arrest are potential therapeutic cancer targets utilized by metformin to boost the anti-cancer effects of *** in vitro and in vivo models have demonstrated the potential of metformin as a chemo-and radiosensitizer,besides its chemopreventive and direct therapeutic activity in digestive system(DS)***,these aspects have been considered in many cancer clinical ***-control and cohort studies and associated meta-analyses have evaluated DS cancer risk and metformin usage,especially in colorectal cancer,pancreatic cancer,and hepatocellular *** clinical studies have demonstrated the protective role of metformin in the risk for DS cancers and survival *** the other hand,the ability of metformin to enhance the actions of chemotherapy for gastric and biliary cancers is yet to be *** article reviews the current findings on the anti-cancer mechanisms of metformin and its apparatus from pre-clinical and ongoing studies in DS malignancies.

关键词： Antidiabetic treatments Gastrointestinal tumors Therapeutic target

Chemical speciation of copper and manganese in solution of a copper-contaminated soil and young grapevine growth with amendment application

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Pedosphere 2023年第3期33卷 496-507页

作者： Daniela basso FACCo Edicarla TRENTIN Gerson Laerson DRESCHER Rodrigo Knevitz HAMMERSCHMITT Carlos Alberto CERETTA Leandro Souza DA SILVA Gustavo bRUNETTo Paulo ademar Avelar FERREIRA Department of Soil Science Federal University of Santa MariaSanta Maria 97105-900(Brazil) University of Arkansas System Division of Agriculture Arkansas 72704(USA) Federal University of Santa Maria Campus Cachoeira do SulCachoeira do Sul 96506-310(Brazil)

Copper(Cu)-based fungicide application to control foliar diseases in grapevine(Vitis vinifera L.)can increase soil Cu *** soils have high natural Cu and manganese(Mn)concentrations,increasing the potential for toxicity to grapevine *** of amendment substances can reduce the concentrations of toxic chemical species of Cu and Mn in soil solution,especially for the soils grown with young *** evaluated the chemical speciation of Cu and Mn in soil solution and young grapevine growth using a contaminated soil with amendment *** seedlings of Paulsen 1103rootstock were grown for 12 months on an old vineyard(>30 years of cultivation)soil without(control)and with vermicompost or limestone *** dry matter,root morphological characteristics,and plant tissue Cu and Mn concentrations were *** cation and anion concentrations,dissolved organic carbon,p H,and chemical speciation of Cu and Mn in soil solution from different soil layers were *** application did not reduce Cu and Mn phytotoxicity,and grapevine plants died after winter *** soluble Mn concentration in soil(5.56 mg L-1in 0–45 cm soil layer)and Mn concentration in plant tissue at pruning(380.8 mg kg-1)might be the primary cause of plant *** application reduced Cu2+and Mn2+chemical species in soil solution,thereby increasing plant *** Cu2+and Mn2+species were negatively correlated(Poot production at pruning(r=-0.92 and-0.97,respectively)and at the end of the trial(r=-0.73 and-0.51,respectively).Limestone application increased grapevine shoot and root dry matter production by 36%and 41%,respectively,while also presenting the highest root length and volume in the 5–10 cm soil *** application is a viable and profitable alternative for reducing soil Cu and Mn availability and their phytotoxic effects.

关键词： bioavailability heavy metal limestone phytoxicity vermicompost vineyard Visual MINTEQ

Analysis of a New Composite Material for Watercraft Manufacturing

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Journal of Marine Science and Application 2016年第3期15卷 336-342页

作者： Alexandre Wahrhaftig Henrique Ribeiro ademar Nascimento Milton Filho Department of Construction and Structures Polytechnic School Federal University of Bahia Rua Aristides Novis 02 5° andar Federacao Salvador BA Brazil CEP: 40210-910 bahia Federal Institute of Education Science and Technology Rua Emidio dos Santos Barbalho Salvador BA Brazil CEP." 40301-015 Brazil CEP." 40210-910 Department of Mechanical Engineering Polytechnic School Federal University of Bahia Rua Aristides Novis 02 5° andar Federagao Salvador BA Brazil CEP." 40210-910 Research and Education Center in Composite Materials (CEPEC) Avenida Laurindo ROgis 360 Cond. Castro Alves BL. llA AP 412 Bela Vista de Brotas Salvador BA Brazil CEP: 40240-550

In this paper, we investigate the properties of an alternative material for use in marine engineering, namely a rigid and light sandwich-structured composite made of expanded polystyrene and fiberglass. Not only does this material have an improved section modulus, but it is also inexpensive, light, easy to manipulate, and commercially available in various sizes. Using a computer program based on the finite element method, we calculated the hogging and sagging stresses and strains acting on a prismatic boat model composed of this material, and determined the minimum sizes and maximum permissible stresses to avoid deformation. Finally, we calculated the structural weight of the resulting vessel for comparison with another structure of comparable dimensions constructed from the commonly used core material Divinycell.

关键词： naval construction computational analysis composite material sandwich-structure expanded polystyrene fiberglass composite structure concepts finite element method economic viability

Influence of pH to Increase Grafting Degree into Fluoropolymers

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open Journal of Polymer Chemistry 2017年第3期7卷 43-56页

作者： Giovanni González-Pérez ademar benevolo lugao Intitute of Nuclear and Energetic Research IPEN-USP S&atilde o Paulo Brazil

Poly(ethylene-alt-tetra-fluoroethylene (ETFE) and poly(tetrafluoroethylene-cohexafluoropropylene) (FEP) were pre-irradiated under air using a Co60 gamma source to graft styrene at low pH. Grafting copolymers were tuned by study of different parameters (monomer, reaction time, temperature, and pH with addition of sulfuric acid (H2So4)). The maximum degree of grafting was 80% and 40% for ETFE and FEP respectively at dose 2 kGy. Influence of low pH in grafting degree by adding sulfuric acid was studied. Grafting degree was examined by infrared (FTIR-ATR), differential scanning calorimetry (DSC) and swelling behavior analysis after sulfonation process.

关键词： ETFE and FEP Grafting Copolymer Enhanced at Low pH

The Entropy Law and the Impossibility of Perpetual Economic Growth

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open Journal of Applied Sciences 2015年第10期5卷 641-650页

作者： Henrique N. Sá Earp ademar R. Romeiro Unicamp-Institute of Mathematics Campinas Brazil Unicamp-Institute of Economics Campinas Brazil

Every production-recycling iteration accumulates an inevitable proportion of its matter-energy in the environment, lest the production process itself will be a system in perpetual motion, violating the second law of Thermodynamics. Such high-entropy matter depletes finite stocks of ecosystem services provided by the ecosphere, hence is incompatible with the long-term growth in the material scale of the economic process. Moreover, the complex natural systems governing such stocks respond to depletion by possibly sudden environmental transitions, thus hindering markets' very ability to adapt to the new equilibrium conditions. Consequently, uncertainty of critical resilience thresholds constrains material economic growth.

关键词： Entropy Perpetual Growth Zero Growth Ecosystem Resilience

Land Use Capability and the Sustainable Scale: An overview of Agriculture in São Paulo State, brazil

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Natural Resources 2022年第8期13卷 171-180页

作者： oscar Sarcinelli ademar Ribeiro Romeiro Lauro Charlet Pereira Sergio Gomes Tosto Núcleo de Economia Agrícola e Meio Ambiente Universidade Estadual de Campinas (UNICAMP) Campinas Brazil EMbRAPA Meio Ambiente Jaguariúna Brazil EMbRAPA Territorial Campinas Brazil

Establishing a sustainable scale in natural resources management enables effective economic and ecological policies and guarantees the long-term sustainability of economic production. In agriculture, land evaluations determine the land use sustainable scales, that is, those that avoid land degradation and allow the provision of food, wood, energy, and ecosystem services over time. The paper assessed São Paulo State’s agricultural sustainability by analyzing the current land use adequacy to the land use capability map that follows FAo 1976 “guide for land evaluation” and was applied to São Paulo by the State Agricultural Secretariat. Results indicate inefficiencies in land use at the state level, where more than one-third of agricultural lands do not satisfy technical land capability indications. According to technical land use capability, more than 4.5 million hectares are being underused (economic inefficiency) and another 2.2 million hectares are being overused (environmental inefficiency). Pasturelands represent the most unsustainable land use, where 3.7 million hectares are allocated in high quality lands with high agricultural production potential, and another 0.7 million hectares are allocated in lands with very low quality for agriculture, most of than area degraded. To achieve sustainability, lands with high agricultural production potential should be used to improve agriculture and food production and, on the other hand, lands with very low agricultural production potential should be used for wood production, agroforestry, ecotourism and natural ecosystems conservation. our results provide a framework for improving land use policies in São Paulo State and highlight an opportunity to achieve land use sustainability.

关键词： Land Use Planning Land Capability Agricultural Sustainability