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Urnfield Culture hilltop settlements are often associated with a predominant function in the settlement pattern. This study challenged the idea of centrality by means of density estimates and spatial inhomogeneous explanatory statistics. Reflecting on the differences in spatial trends and material culture, no conclusive evidence for a consolidation of power, economic, or cultic dominance was observed. The dataset strongly points towards the inapplicability of commonly used parametric and/or homogenous spatial algorithms in archaeology. Tracer variables as well as the methodological and theoretical limitations are critically reviewed and a methodological framework to increase the reproducibility and reusability of archaeological research is proposed.

A series of polycyclic aromatics, naphthalene, phenanthrene, perylene, pyrene, 1-pyrenebutyric acid N-hydroxysuccinimide ester (pyrene NHS) and coronene, were immobilized via π stacking on carbon nanotube (CNT) electrodes and electro-oxidized in aqueous solutions. The obtained quinones were characterized and evaluated for the mediated electron transfer with FAD dependent glucose dehydrogenase during catalytic glucose oxidation.

International audience; A particularly efficient redox mediator for electron transfer between FAD‐dependent glucose dehydrogenase (FAD‐GDH) and carbon nanotube (CNT) based electrodes can be obtained via electrosynthetic oxidation of pyrene in aqueous buffer solution. 1H‐NMR spectroscopic studies reveal the formation of a 2 : 1 mixture of 1,6‐pyrenedione and 1,8‐pyrenedione at the electrode. The formed pyrenedione exhibits a well‐defined surface‐bound redox system at −0.1 V vs. SCE and provides excellent electron transfer kinetics with this enzyme. Furthermore, the π‐system of pyrenedione allows improved stacking behavior with the CNT walls, leading to enhanced stabilities compared to commonly used mediators like naphthoquinone. The electrosynthesis of pyrenedione for catalytic glucose oxidation is optimal at pH 2 using cyclic voltammetry or chronoamerometry. It is envisioned that the electrosynthetic methodology can be expanded to form different redox mediators for a series of enzymes.

In this work, a pecan nutshell was used as a precursor to prepare activated hydrochar (HPN-ATV) with a high specific area. HPN-ATV was engineered as an adsorbent for the removal of methylene blue (MB) from aqueous environments. The obtained materials were characterized using textural, morphological, and chemical analysis techniques. HPN-ATV showed a BET specific area of 2342 m2 g−1 and an average pore diameter of 2.24 nm. Boehm titration and FTIR spectral analysis indicated the presence of acidic and basic functional groups on the surface of HPN-ATV, which rendered the removal of cationic molecules more favorable. The kinetic experimental data better correlated with the pseudo-second-order kinetic and Elovich equations, and the Langmuir model showed a better fit for the data of MB adsorption. The adjusting parameters indicated a monolayer with an adsorption capacity of 1190.62 mg g−1, which is higher than that of the other adsorbents reported in literature. In addition, the thermodynamic data suggested a spontaneous adsorption process with endothermic characteristics.

The influence of hydrothermal carbonization of sisal fibers on the mechanical properties of composites based on recycled polypropylene matrices was investigated in this paper. The fibers were chara...

Research in biosensing currently occupies an important role among biomolecular detection techniques, especially with respect to medical diagnoses. Is this sense, the development of biosensors based on the localized surface plasmon resonance (an optical transducer) or electrochemical transductions have been highlighted. However, optical and electrochemical detection working together enable more versatile detections in biosensing. Thus, we propose a dual sensor, which incorporates these two mechanisms on the same platform. The sensor shared the same transducer that was based on a glass-indium thin oxide (ITO) surface covered with gold nanoparticles. The transducer was prepared by the immobilization of gold nanoparticles on (3-aminopropyl)triethoxysilane-activated glass-ITO. The substrate ability to respond to physical surface variations was assessed. For this, measurements of the gold nanoparticles band redshift (plasmonic transduction) and charge transfer resistance from impedance spectra (electrochemical transduction) were performed. The platform was able to detect streptavidin immobilized on the surface by both mechanisms demonstrating its applicability as a device for biodetection in dual detection mode.

Localized surface plasmon resonance (LSPR) is a collective oscillation of free electrons induced by the incident light in nanometric surfaces of conductive materials. Gold nanorods (AuNRs) have been studied for plasmonic devices due to their anisotropic properties. Herein, we report the construction of a specific biosensor using polyacrylamide (PAAm) as the gold nanorods support and test its efficiency with specific streptavidin interaction using biotinylated substrates. First, the hydrogels were synthesized by electropolymerization using cyclic voltammetry on ITO/glass substrates and swallowed with AuNRs. The AuNRs were characterized by visible absorption spectroscopy and transmission electron microscopy. The substrates were characterized by scanning electron microscopy and their plasmonic sensitivities were evaluated using sucrose solutions with different concentrations. The results showed a sensitivity of ca. 226.4 nm RIU-1 with linear correlation of 0.9974. Furthermore, this composite presented reliable detection of the streptavidin biomolecule in the gold surface with good signal-to-noise ratio (SNR).

This paper reports the synthesis of a microporous sustainable Zeolite A material using an agroindustry solid waste (SZA) and its functionalization with silver nanoparticles. Silver nanoparticles with ca. 9.0 nm of diameter onto SZA where were obtained using a sodium citrate reduction route. The release transport properties of Ag+ ions from SZA were investigated. We found that silver ions released from the SZA is controlled by the pseudo-Fickian diffusion mechanism. Furthermore, its demonstrate that the Colony-Forming Units (CFU) of (L. monocytogenes; P. auriginosa; S. aureus; S. typhinimurium; E. coli and S. epidermidis) decreases significantly after exposure to the SZA loaded with silver nanoparticles. The antimicrobial activity of this SZA loaded with silver nanoparticles relies on the exposure time with microorganism and concentration of these materials.

NLS was used to prepare holed plasmonic substrates with high sensitivity to streptavidin detection. SEM and AFM characterizations showed substrates with holes distribution of 240.1 ± 27.8 nm and periodicity of 420.2 ± 25.4 nm. These substrates showed a sensitivity of 382.40 ± 11.60 nm/RIU in solutions with different refractive indexes. The sensor has demonstrated high sensitivity in the biosensing of biotin-streptavidin. The immunoassay showed a 1.8 ± 0.3 nm LSPR peak redshift in the protein detection. This work forms a foundation towards the cost-effective plasmonic biosensors.

Objectives This study evaluated the efficacy of a thiourethane(TU)-modified silane agent in improving properties in filled composites. Methods The TU-silane agent was synthesized by combining 1,3-bis(1-isocyanato-1-methylethyl)benzene and 3-(triethoxysilyl)propyl isocyanate with trimethylol-tris-3-mercaptopropionate (TMP), at 1:2 isocyanate:thiol, leaving pendant thiol and alkoxy silane groups. Barium glass fillers (1 μm average particle size) were functionalized with 5 wt% TU-silane in an acidic ethanol solution. Commercially available 3-(trimethoxysilyl)propyl methacrylate (MA-silane) and (3-mercaptopropyl)trimethoxysilane (SH-silane), as well as no silane treatment (NO-silane), were used as controls. Composites were made with BisGMA-UDMA-TEGDMA (5:3:2), camphorquinone/ethyl-4-dimethylaminobenzoate (0.2/0.8 wt%) and di-tert-butyl hydroxytoluene (0.3 wt%) and 70 wt% silanated inorganic fillers. Polymerization stress (PS) was measured using a cantilever beam apparatus (Bioman). Methacrylate conversion (DC) and rate of polymerization (RP) during photoactivation (800 mW/cm2) were followed in real-time with near-IR. Flexural strength/modulus (FS/FM) were evaluated in three-point bending with 2 × 2 × 25 mm. Statistical analysis: 2-way ANOVA/Tukey’s test (α = 5%). Results DC, Rpmax and E were similar for all groups tested. FS was similar for the TU- and MA-silane, which were statistically higher than the untreated and SH-silane groups. Stress reductions in relation to the MA-silane were observed for all groups, but statistically more markedly for the TU-silane material. This is likely due to stress relaxation and/or toughening provided at the filler interface by the oligomeric TU structure. Significance TU-silane oligomers favorably modified conventional dimethacrylate networks with minimal disruption to existing curing chemistry, in filled composites. For the same conversion values, stress reductions of up to 50% were observed, without compromise to mechanical properties or handling characteristics.

Polyethylene terephthalate (PET) is a very stable polymer widely used in the modern world. Due to its stability, this polymer can remain in the environment for several years before its complete degradation. The glycolysis reaction of PET has emerged as a green approach to obtain the PET monomer, thus avoiding such environmental problems and adding value to this waste. In this work, PET waste was depolymerized by glycolysis using ultrasmall cobalt nanoparticles (1.5 wt %) as the catalyst for the production of bis-2-hydroxyethyl terephthalate (BHET). A capping agent (tannic acid, TA) and a borohydride reduction approach were used to obtain such ultrasmall cobalt nanoparticles (∼3 nm). A PET depolymerization yield of 96% was achieved within 3 h at 180 °C. The precipitation of 77% of pure BHET was achieved without the need for water. The remaining ethylene glycol solution containing the ultrasmall cobalt nanoparticle catalyst was reused five times for this glycolysis process, demonstrating the feasibility of ...

The aim of this study was to synthesize and characterize mesoporous materials SBA-15 and SBA-15 modified with 3-(methacryloxy)-propyl-trimethoxysilane (MPS) to be used as inorganic filler in restorative dental composites and adhesives, and evaluate the main physical-chemical properties of the resulting material. The SBA-15 and SBA-15/MPS were characterized by FTIR, BET and X-Ray and combined with TEGDMA, bis-GMA and commercial spherical silica to produce dental composites. Afterwards, the mesoporous materials were combined with TEGDMA, bis-GMA and HEMA to make adhesives. To compare the results, composites and adhesives containing only commercial spherical silica were investigated. Some physical-chemical properties such as degree of conversion (DC), flexural strength (FS) and modulus (FM), water sorption and solubility (Wsp and Wsl), specific area (BET), and the leachable components were evaluated. The SBA-15/MPS can be used to prepare dental restorative materials, with some foreseeable advantages compared with pure SBA-15 dental materials and with improved properties compared with commercial spherical silica dental materials. An important improvement was that the dental materials based on modified SBA-15 presented a reduction of approximately 60% in leaching of unreacted monomers extracted by solvent compared to the control group.

Objectives This study evaluated three different sterilization/disinfection techniques for resin composites on bacterial growth and surface modification after decontamination. Methods Two resin composites were sterilized/disinfected with three different techniques: UV light, 1% chloramine T, and 70% ethanol. Four different times were used for each technique to determine the shortest time that the solution or UV light was effective. The influence of sterilization/disinfection technique on bacterial growth was evaluated by analyzing the metabolic activity, using the AlamarBlue™ assay, bacterial viability, and SEM images from biofilms of Streptococcus mutans. The surface change, after the process, was analyzed with ATR/FTIR and SEM images. The solutions used for decontamination (1% chloramine-T and 70% ethanol) were analyzed with 1H-NMR to identify any resin compounds leached during the process. Results One minute of decontamination was efficient for all three methods tested. Chloramine-T increased the surface porosity on resin composites, no changes were observed for UV light and 70% ethanol, however, 1H-NMR identified leached monomers only when 70% ethanol was used. No chemical change of the materials was found under ATR/FTIR analyses after the decontamination process. Chloramine-T, with no previous wash, increased the bacterial viability for both resin composites and increased the bacterial metabolism for the resin composite without fluoride. Conclusion UV light had no interference on the resin composites properties tested using 1 min of exposure compared to the other decontamination methods. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017.

The aim of this study was to synthesize and characterize new multifunctional-urethane-methacrylate monomers to be used as the organic matrix in restorative dental composites, and evaluate the main physical-chemical properties of the resulting material. Bis-GMA (bisphenol-A-diglycidylmethacrylate) and GDMA (glycerol dimethacrylate) were modified by reacting the hydroxyl groups with isocyanate groups of urethane-methacrylate precursors to result in the new monomeric systems U-(bis-GMA)-Mod and U-(GDMA)-Mod, U=Urethane and Mod=Modified. The modifications were characterized by FTIR and 1H NMR. The final monomeric synthesized system was used to prepare dental resins and composites. The physical-chemical properties were evaluated and compared with those of bis-GMA composites with varying filler contents or unfilled resins. U-(bis-GMA)-Mod and U-(GDMA)-Mod can be used to prepare dental restorative composites, with some foreseeable advantages compared with bis-GMA composites. One significant advantage is that these composites have the potential to be less toxic, once they presented a reduction of 50% in leaching of unreacted monomers extracted by solvent.

Thiourethane oligomers added to methacrylate matrices improve fracture toughness and reduce polymerization stress. In this study, the oligomers are added to the surface of inorganic fillers in the formulation of resin composites. Systematically varied fillers treated either with the thiourethane or a methacrylate silane control are tested. Thiourethane reduces the rate of polymerization of light-cured composites but does not affect the final degree of conversion (DC). Filler functionalization with thiourethane increases the depth of polymerization, in filler type-dependent fashion. Thiourethane reduces the polymerization stress for all fillers. The findings suggest that this approach results in the same general effects with the addition of thiourethanes directly to the matrix. This is accomplished with a lower overall concentration of thiourethane, and with no prejudice to the handling characteristics of the material.

A metal organic framework with a unique form was prepared using a conventional microwave oven and changing the ratio between metal (zinc) and ligand (1,3,5 tricarboxylic acid). The powder X-ray diffraction (PXRD) shows that the increase of metal content in the synthesis gives more crystalline materials as seen by the scanning electron microscopies (SEM). Moreover, by SEM the ratio 1:4 (ligand:metal) exhibited a unique cauliflower like structure with an average size of 16.9 ± 4.7 µm.

Objective: In this study, the effects of two different cure protocols upon the properties of composites using a hybrid-polymer as dental resin were evaluated. Material and Methods: Two distinct dental composites were prepared, one containing a mixture of TEGDMA/bis-GMA (50:50) and, another containing a mixture of TEGDMA/p-MEMO (50:50), [p-MEMO: oligomeric inorganic precursor]. Both composites were polymerized with lucirin and canphorquinone as photoinitiators. The composites were made with a 70 % wt of inorganic filler. Flexural strength was evaluated with a universal test machine and the degree of conversion was measured by infrared spectroscopy. A helium pycnometer was used to obtain polymer shrinkage data. Sorption tests were performed and SEM microscopy was used to show deleterious effects upon the resins’ surfaces. Results: The sample base on TEGDMA/p-MEMO polymerized with lucirin (L-T/p) showed the best values of the monitored properties. Conclusion: Lucirin is the most suitable photoinitiator for dental composites containing hybrid polymers.KeywordsDental resins; Flexural strength; Hybrid polymer; Photoinitiator system; Polymerization shrinkage.

A composite material based on a metal organic framework (MOF), nanowhisker of Al2O3 silanized with (3-aminopropyl)triethoxysilane (APTES) and gold nanoparticles (AuNp) was synthesized and characterized. This material was used to prepare an electrode based in carbon paste (CPE) and applied as a sensor for the determination of bisphenol A (BPA). The electrochemical characterizations and behaviour of the electrode containing the AuNp@MOF composite exhibited a 2.3 higher electroactive surface area, when compared with just CPE. Using differential pulse voltammetry (DPV), it can be noted that the presence of AuNp plays an important role in enhancing the analyte signal detection of BPA 2.5-fold. A linear increase in emphasizing the response as a function of analyte concentration is demonstrated. In this account, we believe that this composite may be applied in analyticals methods for the determination of BPA and others endocrine disruptors.

This work shows a facile modification of a modified domestic microwave oven that allows for the control of solvent losses and the monitoring of temperature during the synthesis of metal-organic frameworks (MOFs) MIL 100 under hydrofluoric acid-free conditions, HKUST-1 with unique properties, and MIL 88B. In order to obtain the best efficiency irradiation, a thermal mapping image from the domestic microwave DMW was obtained. The results showed that the chemical properties of the produced MOFs were excellent: the observed yield calculation and the BET surface area of the MIL-100 active crystals were 97% and 1300 m2g−1, respectively, and 90% and 1365 m2g−1, respectively for HKUST-1 with unique properties. A simple and low-cost alternative to a commercial microwave oven was developed, making it safer and its parameters controllable during the synthesis of MOFs.

This study aimed to evaluate the efficiency of an electro-Fenton system, using a gas diffusion electrode (GDE) modified with reduced graphene oxide (rGO) for the electrogeneration of H2O2. The process was intensified using magnetic nanoparticles (Fe3O4) supported in graphene oxide (GO) as high-performance heterogeneous Fenton-like catalyst for degradation of textile wastewater. The GDE composed by carbon/PTFE produced 116.0 mg L−1 of H2O2. The modification of GDE with 5 % of rGO increased by about 83.0 % in the H2O2 generation (from 116.0–212.0 mg L−1). The catalyst modified with 15 % of GO presented in the high reduction of turbidity (98.5 %), COD (81.7 %) and TOC (70.3 %) and an excellent stability during ten cycles of reuse. The GO in addition to providing Fe3O4 stability also contributes to the generation of hydroxyl radicals ( OH). The in situ H2O2 generation combined with a reusable catalyst made the process more efficient, economical and eco-friendly.

Tumor necrosis factor-alpha (TNF-α) is a signaling protein of inflammatory processes. TNF-α overexpression triggers inflammatory processes related to various diseases such as rheumatoid arthritis, Crohn’s disease, Chagas, and others. For this reason, the TNF-α has been used as an important biological biomarker for prognosis, understanding, and disease treatment. Surface plasmon resonance (SPR)-based biosensors are a good alternative for TNF-α detection because they are more sensitive than other techniques and have the ability to be developed miniaturized systems. Then we developed a nanohole array on gold nanofilm-based SPR biosensor for TNF-α detection. A biological biorecognition system (cysteamine/biotin/streptavidin/TNF-α antibody) was formed and TNF-α antigen was detected by transmitted light intensity monitoring. TNF-α antigen at 17 pg mL − 1 was detected from fungus Paracoccidioides brasiliensis-infected rat blood serum. This concentration is far below those found in similar studies in the literature. This plasmonic device opens new opportunities for TNF-α detection.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico The aim of this in vitro study was to synthesize three new methacrylate monomers based on the modification of saccharides structures (glucose-Gluc, sucrose-Sucr and chitosan-Chit) with glycidyl methacrylate, and to use them in the composition of dental adhesives. Three methacrylate saccharide monomers were synthesized and characterized by mid-IR, 1H and 13C NMR, antioxidant activity and cytotoxic effect. Monomers included: one monosaccharide – Gluc-MA; one disaccharide – Sucr-MA; and one polysaccharide – Chit-MA. Primers containing HEMA, methacrylate saccharide monomers at concentrations of 0 (control), 1, 2 or 4 wt%, 60 wt% ethanol aqueous solution (pH3.0) and initiator system were formulated. Primers were used in conjunction with a bond step and composite paste to restore caries-free third molars, and dentin bond strength (24 hours and 6 month of storage in water), and antimicrobial activity (Alamar Blue test) were tested. Degree of conversion (DC) and maximum rate of polymerization (Rpmax) of the primers themselves were also analyzed. The mid-IR, 1H and 13C spectrum confirmed the presence of vinyl group on the structure of saccharides. Chit-MA showed low antioxidant activity and did not present a cytotoxic effect. Gluc-MA and Sucr-MA possess antioxidant and cytotoxic activity, concentration dependent. In the presence of methacrylate saccharide monomers, the primers showed DC comparable to the control group, except Gluc-MA4%, Sucr-MA4% and Chit-MA1%, which showed a range of 64.6 from 58.5 %DC. Rpmax was not statistically different for all the groups (p = 0.01). The bond strength of Sucr-MA1% increased from 25.7 (±2.8) to 40.6 (±5.3) MPa after 6 months of storage. All the synthesized monomers showed some antimicrobial activity after polymerization. Gluc-MA and Chit-MA 4% and Sucr-MA 1, 2 and 4% led to decrease bacterial metabolism. Sucr-MA 1% showed better results regarding the decrease in bacterial metabolism and increasing the bond strength after 6 months of storage.

Elevated levels of non-accidental fractures in different populations, regions, and time periods are considered an indicator for violence within a population. Whilst soldiers from a mass grave contribute unambiguously to the bioarchaeological evidence for the presence of warfare in medieval England, we aim to further analyse the absence of temporal variation in the general population-wide fracture distribution pattern. A detailed study, consisting only of clearly dated and aged male individuals was conducted to investigate the impact of prolonged warfare and general instability by means of blunt force fracture distribution patterns in early (AD 1066-1100), middle (AD 1100-1380) and late (AD 1380-1558) medieval England. Statistically significant differences were only observed between the 26-35 years age group of the middle period (AD 1100-1380) vs the 18-25 year age group of the late period (AD 1380-1558). The latter included many individuals from Towton, North Yorkshire, and therefore battle-related injuries are reflected in the pattern. The former presented inconclusive causal effects, none of them could be reliably linked to warfare. It was concluded that aside from the inclusion of battle-related graves no evidence for the impact of prolonged warfare and economic instability could be observed in medieval England.

Polysaccharide-based composite materials (beads) containing silver nanoparticles (AgNPs) were successfully prepared. Hydrogel beads acted as an efficient vehicle for Ag+ delivery. Beads promoted the AgNPs protection and inhibited their aggregation. Antimicrobial assays showed that the beads/AgNPs concentration can be modulated to deliver an amount of Ag+ necessary for kill Escherichia coli cells.

Polyelectrolyte complex (beads) based on N , N , N -trimethyl chitosan/alginate was successful obtained and silver nanoparticles (AgNPs) were loaded within beads. In vitro cytotoxicity assays using beads/silver nanoparticles (beads/AgNPs) provided results, indicating that this material significantly inhibited the growth of colon cancer cells (Caco-2). In vitro release studies showed that the beads stabilized AgNPs and repressed Ag 0 oxidation under gastric conditions (pH 2.0). On the other hand, at physiological condition (pH 7.4) the beads/AgNPs released 3.3 μg of Ag + per each beads milligram. These studies showed that the concentration of Ag + released (3.3 μg) was cytotoxic for the Caco-2 cells and was not cytotoxic on healthy VERO cells. This result opens new perspectives for the manufacture of biomaterials based on beads/AgNPs with anti-tumor properties.

Biosensors based on surface plasmon resonance (SPR), operating with the Kretschmann conventional arrangement, have been employed for biomolecular detection of tumor markers. However, the traditional SPR configuration presents some experimental inconveniences that are overcome by using plasmonic substrates based on nanohole arrays manufactured in metallic films. This SPR configuration exhibits the extraordinary optical transmission (EOT) phenomenon, which is explored in the monitoring of binding events that occur on the metal surface. In this work, we proposed a plasmon biosensor based on nanohole arrays built on gold film operating in collinear transmission mode by using spectral investigation for signal transduction. The SPR substrate was coupled to a microfluidic system and showed good sensitivity and linearity. A concentration of 30 ng mL−1 of human epidermal receptor protein-2 (HER2) antigen (associated with breast cancer) was detected using the integrated device; this showed its great potential to be used in tumor diagnosis.

Made available in DSpace on 2015-08-26T19:22:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-01. Added 1 bitstream(s) on 2015-08-31T13:04:10Z : No. of bitstreams: 1 S0103-84782015000500767.pdf: 654516 bytes, checksum: 7c30618310f404ddd2d56c19c8a90ecb (MD5) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Este estudo teve como objetivo investigar a tolerância ou susceptibilidade das espécies de capim-colchão (Digitaria ciliaris, D. horizontalis e D. nuda) a herbicidas inibidores do fotossistema II (FSII), por meio da técnica da fluorescência, utilizando a taxa de transferência de elétrons do FSII como indicador. Para isso, foi conduzido um experimento em esquema fatorial 3x6, com três espécies de capim-colchão e seis tratamentos (ametryn, hexazinone, diuron+hexazinone, amicarbazone, diuron, tebuthiuron e testemunha) aplicados em pós-emergência. Foi monitorada a taxa de transporte de elétrons (ETR) do FSII em intervalos de tempo crescente e aferida a massa seca das plantas aos 21 dias após a aplicação. A partir dos dados da ETR, calculou-se um valor numérico representativo da taxa de inativação da ETR. Os resultados demonstraram que todas as espécies de capim-colchão estudadas são susceptíveis aos herbicidas ametryn e hexazinone (valores da taxa de inativação da ETR superiores a 10.000). Os herbicidas diuron e tebuthiuron apresentaram menores taxas de inativação da ETR para a D. nuda (3.585 e 3.497, respectivamente) e maiores para as espécies D. ciliaris e D. horizontalis (acima de 10.000), enquanto que o herbicida amicarbazone apresentou valor intermediário para D. nuda (7.967). O monitoramento da ETR foi eficiente para verificar a atuação dos herbicidas nas diferentes espécies estudadas This study aimed to investigate the tolerance or susceptibility of crabgrass species (Digitaria ciliaris, D. horizontalis and D. nuda) to herbicides that target photosystem II (PSII), by fluorescence technique using the electron transport rate (ETR) through PSII as an indicator. An experiment was conducted under a factorial arrange (3x6), with three species of crabgrass and six treatments (ametryn, hexazinone, diuron+hexazinone, amicarbazone, diuron, tebuthiuron and control) applied in post-emergence. The ETR through PSII was monitored over time and the plants dry weight measured at 21 days after application. A numerical value of the ETR inactivation was calculated from the data collected. The results showed that the three crabgrass species studied are susceptible to ametryn and hexazinone (ETR inactivation value higher than 10,000). Moreover, diuron and tebuthiuron provided lower ETR inactivation for D. nuda (3,585 and 3,497, respectively) and higher rates for D. horizontalis and D. ciliaris (more than 10,000), whereas amicarbazone showed intermediate inactivation rate for D. nuda (7,967). Monitoring the ETR showed to be an efficient form to verify the herbicides performance in the different species studied here Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP) - Departamento de Proteção Vegetal, Faculdade de Ciências Agronômicas (FCA), , 18610-307, Botucatu, SP, Brasil. Departamento de Produção e Melhoramento Vegetal, FCA, UNESP, Botucatu, SP, Brasil. Universidade Estadual Paulista "Júlio de Mesquita Filho" (UNESP) - Departamento de Proteção Vegetal, Faculdade de Ciências Agronômicas (FCA), , 18610-307, Botucatu, SP, Brasil. Departamento de Produção e Melhoramento Vegetal, FCA, UNESP, Botucatu, SP, Brasil. MCT/CNPq: 70/2009

Polyelectrolyte complex beads based on N,N,N-trimethyl chitosan (TMC) and sodium alginate (ALG) were obtained. This biomaterial was characterised by FTIR, TGA/DTG, DSC and SEM analysis. The good properties of polyelectrolyte complex hydrogel beads were associated, for the first time, with gold nanoparticles (AuNPs). Through a straightforward methodology, AuNPs were encapsulated into the beads. The in vitro cytotoxicity assays on the Caco-2 colon cancer cells and healthy VERO cells showed that the beads presented good biocompatibility on both cell lines, whereas the beads loaded with gold nanoparticles (beads/AuNPs) was slightly cytotoxic on the Caco-2 and VERO cells.

Resumo Foi discutida neste estudo a influência de nanopartículas de sílica na compatibilidade entre fibras de sisal e polietileno de alta densidade, utilizados na preparação de compósitos. As fibras de sisal foram tratadas quimicamente e recobertas com nanopartículas de sílica por moagem mecânica. Os compósitos foram preparados por extrusão do polietileno com diferentes quantidades de fibras. Utilizou-se diferentes técnicas de caracterização para se obter as propriedades térmicas e a morfologia das fibras de sisal e dos compósitos, a influência das fibras de sisal e da sílica na cristalinidade do polietileno e o comportamento mecânico e a absorção de água do polietileno e dos compósitos. Foi observado que a as propriedades térmicas do polietileno não são afetadas pela presença das fibras e nanopartículas. Os diferentes tratamentos químicos e a presença de sílica nas fibras de sisal resultaram em propriedades mecânicas melhoradas e foram preponderantes para a diminuição da absorção de água nos compósitos, comparados ao polietileno. Abstract In this study, the influence of silanized silica nanoparticles on the compatibility of composites prepared with sisal fibers and high density polyethylene is discussed. The sisal fibers were chemically treated and covered with silica nanoparticles by mechanical milling. The composites were prepared by extrusion of HDPE and different amount of fibers. The morphology and thermal properties of the sisal fibers and composites, the influence of sisal fibers and silica nanoparticles on crystallinity of HDPE, the mechanical behavior and water uptake of composites were evaluated by different techniques. It was observed that thermal properties of HDPE on composites were not changed by the presence of sisal fibers and silica nanoparticles. The different chemical treatments in sisal fibers and the presence of silica nanoparticles resulted in improved mechanical properties and were preponderant to the water uptake decrease in the composites, comparing with HDPE.

Objectives To synthesize and characterize different molar weight urethane multimethacrylates with a single stage (one-pot) procedure. To prepare and characterize the properties of related composites. Methods Two methacrylate precursors were initially synthesized. Then, these precursors and the multimethacrylate system formed by their coupling were characterized by FTIR and 1 H NMR. The final product was used as a matrix (with TEGDMA and SiO 2 silanized microparticles) in the preparation of composites and their physical and mechanical properties were compared to those of a bis-GMA-based resin. Water sorption and solubility measurements of the composites were also performed. Results FTIR and NMR suggested that the proposed synthesis route yields a mixture of mainly urethane-di, -tri, and tetramethacrylates. The composites presented low polymerization shrinkage ( e.g. 1.88 ± 0.08% for a resin with 70% of SiO 2 ) and high flexural strength ( e.g. 124.74 ± 9.68 MPa for a resin with 65% of SiO 2 ) when compared to the bis-GMA based resin and other composites found to date. Water sorption and solubility results show that the composites were deemed compliant with ISO 4049 requirements. Significance The mixture containing different molar weight of urethane multimethacrylates showed to be an excellent substitute for bis-GMA, achieving an equilibrium of properties (unlike reports elsewhere which show the enhancement of some parameters in detriment to others) and composites with low polymerization shrinkage, suitable microhardness and degree of conversion, and up to standard water sorption/solubility and flexural strength.

This work focused on the plasmonic sensitivity of a substrate composed of gold nanoparticles (AuNp) and 3-aminopropyltriethoxysilane (APTES)-modified graphene oxide (GO-APTES). The multilayered system fabricated by dip-coating was analyzed by means of FTIR spectroscopy and scanning electron microscopy (SEM). The localized surface plasmon resonance (LSPR) band of AuNp was shifted from ca. 520 nm (monolayer of AuNp) to ca. 600 nm (multilayered with GO), which was a result of the agglomeration of AuNp. SEM micrographies revealed a system containing agglomerated grapheme oxide sheets on the substrate. An unprecedented sensitivity profile, determined in different refractive index (RI) media, was ca. 460 nm/RIU. The bio-sensitivity of the substrate was evaluated by immobilization of BSA on MUA-NHS-treated Au/GO, which presented a shift of 2.07 nm after binding to the protein.

The X/A zeolite crystal mixtures were synthesized using sugar cane bagasse ash (SCBA) as a silicon source and multilayer food packing (MFP) as an aluminum source under hydrothermal conditions at 80 °C for 79–296 hours. The silicon was extracted by alkaline fusion for 40 min at 550 °C with an alkali–SCBA weight ratio of 1:1. The aluminum solution was obtained from MFP using NaOH 1 M (3:1 water–acetone) solution. The synthesized zeolites were analyzed by XRD, FTIR, SEM, and BET. In the XRD results, most of the signals were indexed to zeolite X, and some signals were indexed to zeolite A. The vibration bands in the region 1200–400 cm−1 suggested the presence of the double-six-ring (D6R) zeolite X structure. The crystal morphology is characteristic of the zeolite X, and the specific area found by the BET method was 810.47 m2 g−1. The zeolite with the higher specific area was applied in the CO2 adsorption process until it reached 25 bar by the gravimetric method. The experimentally adsorbed amounts were adjusted with the Langmuir, Freundlich, and Toth models.

HER2 antigen is a marker used for breast cancer diagnosis and prevention. Its determination has great importance since breast cancer is one of the most insidious types of cancer in women. HER2 antigen assessment in human serum is traditionally achieved by enzyme-linked immunosorbent assay (ELISA method), but it has some disadvantages, such as suppressing the thermodynamic–kinetic studies regarding the antibody–antigen interaction, and the use of labeled molecules that can promote false positive responses. Biosensors based on surface plasmon resonance (SPR) are sensitive optical techniques widely applied on bioassays. The plasmonic devices do not operate with labeled molecules, overcoming conventional immunoassay limitations, and enabling a direct detection of target analytes. In this way, a new SPR biosensor to assess HER2 antigen has been proposed, using nanohole arrays on a gold thin film by signal transduction of transmitted light measurements from array image acquisitions. These metallic nanostructures may couple the light directly on surface plasmons using a simple collinear arrangement. The proposed device reached an average sensitivity for refractive index (RI) variation on a metal surface of 4146 intensity units/RIU (RIU = RI units). The device feasibility on biomolecular assessment was evaluated. For this, 3 ng ml−1 known HER2 antigen concentration was efficiently flowed (using a microfluidic system) and detected from aqueous solutions. This outcome shows that the device may be a powerful apparatus for bioassays, particularly toward breast cancer diagnosis and prognosis.

Thiourethane oligomers added to methacrylate matrices improve fracture toughness and reduce polymerization stress. In this study, the oligomers are added to the surface of inorganic fillers in the formulation of resin composites. Systematically varied fillers treated either with the thiourethane or a methacrylate silane control are tested. Thiourethane reduces the rate of polymerization of light-cured composites but does not affect the final degree of conversion (DC). Filler functionalization with thiourethane increases the depth of polymerization, in filler type-dependent fashion. Thiourethane reduces the polymerization stress for all fillers. The findings suggest that this approach results in the same general effects with the addition of thiourethanes directly to the matrix. This is accomplished with a lower overall concentration of thiourethane, and with no prejudice to the handling characteristics of the material.

In this work, sugarcane bagasse fibers were used as filler in composites having recycled high-density polyethylene (PEr) as matrix. Because of the poor interaction between fibers surface and the PEr, the surface of bagasse was chemically modified. This modification consists of washing with water at 80°C, a mercerization process using sodium hydroxide and acetylation reaction with acetic anhydride. The chemical modification was characterized by Fourier transform infrared–horizontal attenuated total reflectance (FTIR-HATR) and 13C nuclear magnetic resonance spectroscopies (NMR), thermogravimetric analysis (TGA), and scanning electronic microscopy (SEM). The composites were prepared from modified and unmodified fibers into PEr matrix, containing 5, 10, and 20% (w/w) of fiber. The samples were processed by extrusion and molds were prepared by injection process in order to perform mechanical tests. These materials were analyzed by SEM, TGA, and the water uptake was evaluated. Also, their mechanical properties were analyzed. Morphological analysis indicated that the chemical modification of sugarcane bagasse increased the compatibility between matrix and reinforcement. Tensile, flexural, and impact tests showed that the mechanical properties of the composite were improved compared to PEr due to the presence of the fibers. POLYM. COMPOS., 35:768–774, 2014. © 2013 Society of Plastics Engineers

Zeolite NaA was synthesized using sugarcane bagasse as silica source under hydrothermal condition at 80 °C for 72–160 h. The silicon was extracted by alkaline fusion for 40 min, at 550 °C with an alkali:ash ratio of 1. Zeolite A was obtained without phase contamination. The ash and synthesized zeolite NaA were analyzed by granulometry, XRD, SEM, FTIR, XRF and TG/DTA. In XRD results, all signals were perfectly indexed to zeolite A. The vibration bands at ca. 557 cm −1 suggested the presence of double-four-ring (D4R) zeolite A structure. The synthesized material has a potential application as a catalyst, as adsorbent, and as an ion exchanger.

This paper presents a factorial design (mixture design) used to analyze the hardness and degree of monomer conversion into composites containing conventional monomers and an organic-inorganic hybrid polymer-based methacryloyloxypropyl trimethoxysilane (MEMO). For this purpose, resins (composites with SiO2) were formulated with the hybrid polymer (polycondensed, pMEMO), and two conventional monomers used in dentistry, bisphenol-A dimethacrylate (Bis-GMA) and triethyleneglycol dimethacrylate (TEGDMA). The resins were characterized through the degree of monomer conversion and Vickers hardness, and the pMEMO by means of FTIR and ¹H NMR. The results showed an increase in hardness for resins containing the hybrid material relative to the resins containing only conventional monomers. The mathematical model adjusted to the experimental data yielded an optimized formulation, which presented a higher hardness value (48.88 HV).

Different properties, such as barriers to gas, light, flavor and water vapor, as well as flexibility, are necessary for the production of food packages. These properties may be obtained by combining different polymers. In spite of the advantages achieved with the use of multilayer films, the recycling process of such material is a challenging task. This study presents an alternative for recycling of a quite common food packaging kind, which contains polyethylene (PE), aluminum and poly(ethylene terephthalate) (PET) as a multilayer film. The multilayer packages were delaminated with acetone. PET was depolymerized by ethanol in supercritical conditions. The diethyl terephthalate (DET) was obtained as the main product, presenting high purity and yield of 80%. Also, metallic aluminum was obtained by the PET-depolymerizing process. The optimal reaction time was 120 min. The products were characterized by FTIR, 1 H NMR and 13 C NMR spectroscopies, DSC and TGA.

Surface plasmon resonance platforms, based on arrays of nanoholes on gold films, were used to detect the binding of organic and biological molecules. Optical sensors were assembled using nanohole arrays with different resonance energies, tuned by adjusting the distance between the holes. A direct relationship between plasmon energy and bulk sensitivity to refractive index changes was verified experimentally. The highest sensitivity ( ca. 463 nm/RIU) was obtained for the (1,0) SPP mode, excited on an array of nanoholes with 455 nm periodicity. Real-time monitoring of the specific biotin–streptavidin binding was also used to demonstrate the influence of transmitted light intensity and FWHM on the sensor performance.

This chapter discusses the single carrier modulation techniques which have been proposed and used in first generation narrowband PLC systems. It emphasizes the recent insight and research focusing first on frequency/phase shift keying combined with permutation coding. The chapter covers multicarrier modulation which is at the heart of latest narrowband and broadband PLC systems. Several known and more recent schemes are here described including OFDM, FMT, Pulse‐shaped OFDM, Wavelet OFDM, OQAM‐OFDM, and Cyclic block FMT. The voltage and current modulation is discussed as a simple and effective means to transmit data at low speed and over long distances. If multiple wires are available, multiple input multiple output (MIMO) transmission schemes can be used to exploit spatial diversity. The chapter also discusses the noise mitigation and error control techniques currently found in various PLC protocols and standards, as well as other promising techniques that are still only found in the literature.

Surface plasmon resonance platforms based on laser inscribed azo polymer surface relief diffraction gratings were used to detect the binding of organic and biological molecules. Optical sensors were assembled to operate in transmission mode, resulting in a very simple setup. This new approach is observed to present a high sensitivity when compared to other systems, such as SPR-based biosensors using nanoholes. The corrugated surface provides a relatively large surface area and the improved sensitivity to binding events is related to resonant plasmon enhancement on the surface relief grating. It was found that varying the periodicity from 400 to 410 nm does not improve efficiency, however changing the groove depth from 30 to 65 nm, resulted in a two-fold increase in sensitivity. An interesting result is that sensors with higher energy surface plasmons present higher sensitivity when compared to lower energy ones. This result can drive further studies toward improved surface plasmon-based sensors.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:52:12Z No. of bitstreams: 1 S0100-83582012000300007.pdf: 675632 bytes, checksum: 1e1ba5946c733fcd77f35310ee060730 (MD5) Made available in DSpace on 2013-08-22T18:52:12Z (GMT). No. of bitstreams: 1 S0100-83582012000300007.pdf: 675632 bytes, checksum: 1e1ba5946c733fcd77f35310ee060730 (MD5) Previous issue date: 2012-09-01 Made available in DSpace on 2013-09-30T19:43:12Z (GMT). No. of bitstreams: 2 S0100-83582012000300007.pdf: 675632 bytes, checksum: 1e1ba5946c733fcd77f35310ee060730 (MD5) S0100-83582012000300007.pdf.txt: 30605 bytes, checksum: e128412a98961d5d0f876f62168def71 (MD5) Previous issue date: 2012-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:19:56Z No. of bitstreams: 2 S0100-83582012000300007.pdf: 675632 bytes, checksum: 1e1ba5946c733fcd77f35310ee060730 (MD5) S0100-83582012000300007.pdf.txt: 30605 bytes, checksum: e128412a98961d5d0f876f62168def71 (MD5) Made available in DSpace on 2014-05-20T13:19:56Z (GMT). No. of bitstreams: 2 S0100-83582012000300007.pdf: 675632 bytes, checksum: 1e1ba5946c733fcd77f35310ee060730 (MD5) S0100-83582012000300007.pdf.txt: 30605 bytes, checksum: e128412a98961d5d0f876f62168def71 (MD5) Previous issue date: 2012-09-01 Este trabalho foi desenvolvido com o objetivo de avaliar a fluorescência através da taxa de transporte de elétrons, consumo de água e intoxicação de plantas de Ipomoea triloba após aplicação de quatro herbicidas de diferentes mecanismos de ação. Os herbicidas aplicados foram: glyphosate, haloxyfop-methyl, diuron e amicarbazone. A aplicação foi feita com auxílio de um pulverizador estacionário instalado em laboratório; após a aplicação dos tratamentos, as plantas foram mantidas em casa de vegetação. Foi avaliada a taxa de transporte de elétrons (ETR), o consumo de água e a intoxicação das plantas em vários períodos após o início do experimento. Os dados de ETR e fitointoxicação foram expressos em porcentagem da testemunha e submetidos à análise de variância e à comparação das médias. Quanto ao consumo de água, os dados foram acumulados e ajustados por modelos de regressão. Assim, pode-se dizer que o fluorômetro é uma ferramenta adequada para verificar a intoxicação antecipada em plantas de I. triloba tratadas com os herbicidas amicarbazone e diuron, visto que a inibição da ETR foi verificada antes de qualquer intoxicação visual sofrida por essas plantas; o consumo de água está relacionado diretamente com o transporte de elétrons, com exceção das plantas submetidas ao haloxyfop-methyl, que não sofreram interferência no transporte de elétrons, mas reduziram o consumo de água. This work was carried out to evaluate fluorescence through electron transport rate (ETR), water consumption and intoxication of Ipomoea triloba after application of four herbicides with different mechanisms of action. The herbicides glyphosate, haloxyfop-methyl, diuron, and amicarbazone were applied using a stationary sprayer installed in the laboratory. After application, the plants were kept under greenhouse conditions. Electron transport rate, water consumption and plant intoxication were evaluated at various periods after the start of the experiment. ETR and intoxication data were expressed as percentage of control and subjected to analysis of variance and comparison of means. The water consumption data were accumulated and adjusted to regression models. Based on the results obtained, it was concluded that the fluorometer is an appropriate tool to verify anticipated toxicity in plants of I. triloba treated with the herbicides amicarbazone and diuron, whereas ETR inhibition was observed before any visual intoxication experienced by the plants. Also, water consumption was found to be directly related to ETR, except for the plants subjected to haloxyfop-methyl which did not suffer electron transport interference, but reduced water consumption. UNESP FCA Dep. de Agricultura UNESP FCA Dep. de Agricultura