Degradation of carbendazim in aqueous solution by different settings of photochemical and electrochemical oxidation processes.

The present study analyzed the performance of photochemical and electrochemical techniques in the degradation and mineralization of the pesticide carbendazim (CBZ). Direct photolysis (DP), heterogeneous photocatalysis (HP), photoelectrocatalysis (PEC), and electrochemical oxidation (EO) were tested, and the influence of UV radiation, current density (j), and supporting electrolyte concentration were evaluated. The results suggest that CBZ is only degraded by DP when UV-C254nm is used. For HP, the CBZ degradation was observed both when UV-A365nm or UV-C254nm were used, which is related to the reactive oxygen species (ROS) formed by the photocatalytic activity (photon-ROS). Neither DP nor HP were able to mineralize CBZ, demonstrating its resistance to photomediated processes. For EO, regardless of the j, there were higher CBZ degradation and mineralization than those observed when using DP and HP. The increase in the supporting electrolyte concentration (Na2SO4) did not affect the levels of degradation and mineralization of CBZ. Concerning the PEC, a CBZ mineralization of 52.2% was accomplished. These findings demonstrate that the EO is the main pathway for CBZ mineralization, suggesting an additional effect of the electro-ROS on the photon-ROS and UV-C254nm. The values of mineralization, kinetics, and half-life show that PEC UV-C254nm with a j of 15 mA cm-2 was the best setting for the degradation and mineralization of CBZ. However, when the values of specific energy consumption were considered for industrial applications, the use of EO with a j of 3 mA cm-2 and 4 g L-1 of Na2SO2 becomes more attractive. The assessment of by-products formed after this best cost-efficient treatment setting revealed the presence of aromatic and aliphatic compounds from CBZ degradation. Acute phytotoxicity results showed that the presence of sodium sulfate can be a representative factor regarding the toxicity of samples treated in electrochemical systems.

Nitrate reduction by electrochemical processes using copper electrode: evaluating operational parameters aiming low nitrite formation.

This work aims to present different electroreduction and electrocatalytic processes configurations to treat nitrate contaminated water. The parameters tested were: current density, cell potential, electrode potential, pH values, cell type and catalyst use. It was found that the nitrite ion is present in all process variations used, being the resulting nitrite concentration higher in an alkaline pH. The increase in current density on galvanostatic operation mode provides a greater reduction of nitrate (64%, 1.4 mA cm-2) if compared to the potentiostatic (20%) and constant cell potential (37%) configurations. In a dual-chamber cell the nitrate reduction with current density of 1.4 mA cm-2 was tested and obtained as a NO3- reduction of 85%. The use of single chamber cell presented 32 ± 3% of nitrate reduction, indicating that in this cell type the nitrate reduction is smaller than in dual-chamber cell (64%). The presence of a Pd catalyst with 3.1% wt. decreased the nitrite (1.0 N-mg L-1) and increased the gaseous compounds (9.4 N-mg L-1) formation. The best configuration showed that, by fixing the current density, the highest nitrate reduction is obtained and the pH presents a significant influence during the tests. The use of the catalyst decreased the nitrite and enhanced the gaseous compounds formation.

Degradation and mineralization of erythromycin by heterogeneous photocatalysis using SnO2-doped TiO2 structured catalysts: Activity and stability.

Heterogeneous photocatalysis was used for the degradation and mineralization of erythromycin (ERY), with a consequent production of carboxylic acids. For that, a series of TiO2 and Ti1-xSnxO2 structured catalysts, namely M1 to M5, was prepared using the washcoating method, with the catalytic coatings being deposited onto stainless steel meshes. Besides, the catalytic activity of the prepared systems was compared to that of the commercial mesh (CM). The results showed that the prepared TiO2 structured catalyst (M1) presented better ERY oxidation than the CM one, what was associated to the higher catalyst load and to the anatase/rutile ratio. Considering the Sn-doped structured catalysts, for M2, M4 and M5 catalysts, lower ERY mineralization and high formation of carboxylic acids were found, when compared to the M3 catalyst. The improved M3 activity was attributed to the formation of a staggered gap (type II heterojunction), providing better charge separation. In this situation, a high generation of hydroxyl radicals is obtained, resulting on a higher ERY mineralization. By the obtained results it is possible to determine that the addition order and the type of Sn compound added in the washcoating process, affects the catalytic activity due to the formation of a solid solution and to the type of produced heterostructures. The M3 catalyst also showed high stability in long-term tests up to 44 h of reaction. The results provide insights into the development of an inexpensive structured catalyst production method and its influence in the stability of the photocatalyst, as well as in its applicability on water/wastewater treatment.

A case of esophageal carcinoma due to esophageal squamous papillomatosis.

INTRODUCTION: Squamous Papilloma is a rare benign tumor of the esophagus. Esophageal squamous papilloma is thought to arise from a chronic inflammatory reaction due to mechanical or chemical irritant. ESP is usually considered to have a benign clinical course; however, some reports highlight the potential development of a malignancy. The development of extensive esophageal squamous papillomas also known as squamous papillomatosis of the esophagus is even less frequent. PRESENTATION OF THE CASE: We present the case of an esophageal papillomatosis that developed into an invasive esophageal squamous cell carcinoma that was only diagnosed in the surgical specimen after minimally invasive Ivor-Lewis esophagectomy and in this case report, we discuss its etiology, diagnosis and treatment. CONCLUSION: Extensive papillomatosis with continuous symptoms, especially persistent dysphagia, should always prompt a thorough analysis into a possible underlying malignancy.

Carbohydrate binding modules enhance cellulose enzymatic hydrolysis by increasing access of cellulases to the substrate.

Plant biomass is a low-cost and abundant source of carbohydrates for production of fuels, "green" chemicals and materials. Currently, biochemical conversion of the biomass into sugars via enzymatic hydrolysis is the most viable technology. Here, the role of carbohydrate binding modules (CBMs) in the disruption of insoluble polysaccharide structures and their capacity to enhance cellulase-promoted lignocellulosic biomass hydrolysis was investigated. We show that CBM addition promotes generation of additional reducing ends in the insoluble substrate by cellulases. On the contrary, bovine serum albumin (BSA), widely used in prevention of a non-specific protein binding, causes an increase in soluble reducing-end production, when applied jointly with cellulases. We demonstrate that binding of CBMs to cellulose is non-homogeneous, irreversible and leads to its amorphisation. Our results also reveal effects of CBM-promoted amorphogenesis on cellulose hydrolysis by cellulases.

On the subtle tuneability of cellulose hydrogels: implications for binding of biomolecules demonstrated for CBM 1.

Cellulose-based hydrogel materials prepared by regeneration from cellulose solutions in ionic liquids, or ionic liquid containing solvent mixtures (organic electrolyte solutions), are becoming widely used in a range of applications from tissue scaffolds to membrane ionic diodes. In all such applications knowledge of the nature of the hydrogel with regards to porosity (pore size and tortuosity) and material structure and surface properties (crystallinity and hydrophobicity) is critical. Here we report significant changes in hydrogel properties, based on the choice of cellulose raw material (α- or bacterial cellulose - with differing degree of polymerization) and regeneration solvent (methanol or water). Focus is on bioaffinity applications, but the findings have wide ramifications, including in biomedical applications and cellulose saccharification. Specifically, we report that the choice of cellulose and regeneration solvent influences the surface area accessible to a family 1 carbohydrate-binding module (CBM), CBM affinity for the cellulose material, and rate of migration through the hydrogel. By regenerating bacterial cellulose in water, a maximum accessible surface area of 33 m2 g-1 was achieved. However, the highest CBM migration rate, 1.76 µm2 min-1, was attained by regenerating α-cellulose in methanol, which also resulted in the maximum affinity of the biomolecule for the material. Thus, it is clear that if regenerated cellulose hydrogels are to be used as support materials in bioaffinity (or other) applications, a balance between accessible surface area and affinity, or migration rate, must be achieved.

A combined variation of Palmaris longus and Flexor digitorum superficialis: Case report and review of literature.

The muscles of the anterior compartment of the forearm often exhibit anatomic variations. During dissection of the upper right limb of a preserved cadaver, morphological variations in the Palmaris longus and Flexor digitorum superficialis muscles were found. The Palmaris longus muscular fibers converged to a tendon that passed beneath the Flexor retinaculum, and inserted at the base of the middle phalanx of the fourth digit, replacing the tendon of Flexor digitorum superficialis. The Flexor digitorum superficialis was divided into two muscular heads: a digastric medial head giving tendons to the second and fifth digits, and a lateral head giving one tendon to the third digit. All these tendons were inserted in the respective digits by two bundles between which were located the tendon of the Flexor digitorum profundus muscle. Variations of flexor muscles must be documented because of their clinical significance and their potential use of these muscles in orthopaedic and reconstructive surgery.

Degradation and inactivation of adenovirus in water by photo-electro-oxidation.

The present study analyzed the efficiency of the photo-electro-oxidation process as a method for degradation and inactivation of adenovirus in water. The experimental design employed a solution prepared from sterile water containing 5.107 genomic copies/L (gc/L) of a standard strain of human adenovirus type 5 (HAdV-5) divided into two equal parts, one to serve as control and one treated by photo-electro-oxidation (PEO) for 3 hours and with a 5A current. Samples collected throughout the exposure process were analyzed by real-time polymerase chain reaction (qPCR) for viral genome identification and quantitation. Prior to gene extraction, a parallel DNAse treatment step was carried out to assess the integrity of viral particles. Integrated cell culture (ICC) analyses assessed the viability of infection in a cell culture. The tested process proved effective for viral degradation, with a 7 log10 reduction in viral load after 60 minutes of treatment. The DNAse-treated samples exhibited complete reduction of viral load after a 75 minute exposure to the process, and ICC analyses showed completely non-viable viral particles at 30 minutes of treatment.

Degradation and inactivation of adenovirus in water by photo-electro-oxidation / Degradação e inativação de adenovírus na água por fotoeletrooxidação

The present study analyzed the efficiency of the photo-electro-oxidation process as a method for degradation and inactivation of adenovirus in water. The experimental design employed a solution prepared from sterile water containing 5.107 genomic copies/L (gc/L) of a standard strain of human adenovirus type 5 (HAdV-5) divided into two equal parts, one to serve as control and one treated by photo-electro-oxidation (PEO) for 3 hours and with a 5A current. Samples collected throughout the exposure process were analyzed by real-time polymerase chain reaction (qPCR) for viral genome identification and quantitation. Prior to gene extraction, a parallel DNAse treatment step was carried out to assess the integrity of viral particles. Integrated cell culture (ICC) analyses assessed the viability of infection in a cell culture. The tested process proved effective for viral degradation, with a 7 log10 reduction in viral load after 60 minutes of treatment. The DNAse-treated samples exhibited complete reduction of viral load after a 75 minute exposure to the process, and ICC analyses showed completely non-viable viral particles at 30 minutes of treatment.

Resumo O presente estudo analisou a eficiência do processo de fotoeletrooxidação como metodologia para a degradação e inativação de adenovírus em água. A concepção experimental emprega uma solução preparada a partir de água estéril contendo 5,107 cópias genômicas/L (gc/L) de uma amostra padrão de adenovírus humano tipo 5 (HAdV-5), dividida em duas partes iguais, uma para servir como controle e outra tratada por fotoeletrooxidação (PEO) durante 3 horas e com uma corrente de 5A. As amostras recolhidas durante o processo de exposição foram analisadas por PCR quantitativo em tempo real (qPCR) para identificação e quantificação do genoma viral. Antes da extração de ácidos nucleicos, um passo de tratamento com DNAse paralelo foi realizado para avaliar a integridade das partículas virais. Um ensaio de qPCR integrado à cultura de células (ICC-qPCR) permitiu analisar a viabilidade de infecção em uma cultura de células. O processo mostrou-se eficaz testada para a degradação viral, com uma redução de 7 log10 da carga viral após 60 minutos de tratamento. As amostras tratadas com DNAse exibiram redução completa da carga viral após uma exposição de 75 minutos ao processo, e a análise de ICC-qPCR mostrou partículas virais completamente não-viáveis ​​em 30 minutos de tratamento.

Degradation and inactivation of adenovirus in water by photo-electro-oxidation

The present study analyzed the efficiency of the photo-electro-oxidation process as a method for degradation and inactivation of adenovirus in water. The experimental design employed a solution prepared from sterile water containing 5.107 genomic copies/L (gc/L) of a standard strain of human adenovirus type 5 (HAdV-5) divided into two equal parts, one to serve as control and one treated by photo-electro-oxidation (PEO) for 3 hours and with a 5A current. Samples collected throughout the exposure process were analyzed by real-time polymerase chain reaction (qPCR) for viral genome identification and quantitation. Prior to gene extraction, a parallel DNAse treatment step was carried out to assess the integrity of viral particles. Integrated cell culture (ICC) analyses assessed the viability of infection in a cell culture. The tested process proved effective for viral degradation, with a 7 log10 reduction in viral load after 60 minutes of treatment. The DNAse-treated samples exhibited complete reduction of viral load after a 75 minute exposure to the process, and ICC analyses showed completely non-viable viral particles at 30 minutes of treatment.

Resumo O presente estudo analisou a eficiência do processo de fotoeletrooxidação como metodologia para a degradação e inativação de adenovírus em água. A concepção experimental emprega uma solução preparada a partir de água estéril contendo 5,107 cópias genômicas/L (gc/L) de uma amostra padrão de adenovírus humano tipo 5 (HAdV-5), dividida em duas partes iguais, uma para servir como controle e outra tratada por fotoeletrooxidação (PEO) durante 3 horas e com uma corrente de 5A. As amostras recolhidas durante o processo de exposição foram analisadas por PCR quantitativo em tempo real (qPCR) para identificação e quantificação do genoma viral. Antes da extração de ácidos nucleicos, um passo de tratamento com DNAse paralelo foi realizado para avaliar a integridade das partículas virais. Um ensaio de qPCR integrado à cultura de células (ICC-qPCR) permitiu analisar a viabilidade de infecção em uma cultura de células. O processo mostrou-se eficaz testada para a degradação viral, com uma redução de 7 log10 da carga viral após 60 minutos de tratamento. As amostras tratadas com DNAse exibiram redução completa da carga viral após uma exposição de 75 minutos ao processo, e a análise de ICC-qPCR mostrou partículas virais completamente não-viáveis em 30 minutos de tratamento.

Toxicity effects of nickel electroplating effluents treated by photoelectrooxidation in the industries of the Sinos River Basin.

The Sinos river Basin is an industrial region with many tanneries and electroplating plants in southern Brazil. The wastewater generated by electroplating contains high loads of salts and metals that have to be treated before discharge. After conventional treatment, this study applied an advanced oxidative process to degrade organic additives in the electroplating bright nickel baths effluent. Synthetic rinsing water was submitted to physical-chemical coagulation for nickel removal. The sample was submitted to ecotoxicity tests, and the effluent was treated by photoelectrooxidation (PEO). The effects of current density and treatment time were evaluated. The concentration of total organic carbon (TOC) was 38% lower. The toxicity tests of the effluent treated using PEO revealed that the organic additives were partially degraded and the concentration that is toxic for test organisms was reduced.

Degradation of cyanotoxins (microcystin) in drinking water using photoelectrooxidation.

The discharge of sewage and industrial effluents containing high concentrations of pollutants in water bodies increases eutrophication. Cyanobacteria, some of the organisms whose growth is promoted by high nutrient concentrations, are resistant and produce several types of toxins, known as cyanotoxins, highly harmful to human beings. Current water treatment systems for the public water supply are not efficient in degradation of toxins. Advanced oxidation processes (AOP) have been tested for the removal of cyanotoxins, and the results have been positive. This study examines the application of photoelectrooxidation in the degradation of cyanotoxins (microcystins). The performance of the oxidative processes involved was evaluated separately: Photocatalysis, Electrolysis and Photoelectrooxidation. Results showed that the electrical current and UV radiation were directly associated with toxin degradation. The PEO system is efficient in removing cyanotoxins, and the reduction rate reached 99%. The final concentration of toxin was less than 1 µg/L of microcystin in the treated solution.

Evaluation of the radiation field and shielding assessment of the experimental area of HIE-ISOLDE.

The ISOLDE facility at CERN is one of the first facilities in the world dedicated to the production of the radioactive ion beams (RIB) and during all its working time underwent several upgrades. The goal of the latest proposed upgrade, 'The High Intensity and Energy ISOLDE' (HIE-ISOLDE), is to provide a higher performance facility in order to approximate it to the level of the next generation ISOL facilities, like EURISOL. The HIE-ISOLDE aims to improve significantly the quality of the produced RIB and for this reason the increasing of the primary beam power is one of the main objectives of the project. An increase in the nominal beam current (from 2 to 6 µA proton beam intensity) and energy (from 1.4 GeV to 2 GeV) of the primary proton beam will be possible due to the upgrade of CERN's accelerator infrastructure. The current upgrade means reassessment of the radiation protection and the radiation safety of the facility. However, an evaluation of the existing shielding configuration and access restrictions to the experimental and supply areas must be carried out. Monte Carlo calculations were performed in order to evaluate the radiation protection of the facility as well as radiation shielding assessment and design. The FLUKA-Monte Carlo code was used in this study to calculate the ambient dose rate distribution and particle fluxes in the most important areas, such as the experimental hall of the facility. The results indicate a significant increase in the ambient dose equivalent rate in some areas of the experimental hall when an upgrade configuration of the primary proton beam is considered. Special attention is required for the shielding of the target area once it is the main and very intensive radiation source, especially under the upgrade conditions. In this study, the access points to the beam extraction and beam maintenance areas, such as the mass separator rooms and the high voltage room, are identified as the most sensitive for the experimental hall from the radiation protection point of view.

Effects of the sol-gel route on the structural characteristics and antibacterial activity of silica-encapsulated gentamicin.

The effects of sol-gel processes, i.e., acid-catalyzed gelation, base-catalyzed gelation and base-catalyzed precipitation routes, on the encapsulation of gentamicin were investigated. The resulting xerogels were characterized using a series of complementary instrumental techniques, i.e., the adsorption/desorption of nitrogen, small-angle X-ray scattering, Fourier transform infrared spectroscopy, diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and scanning electron microscopy. The encapsulated gentamicin samples were tested against a series of Gram-positive and Gram-negative bacterial strains. The best antimicrobial activity was observed with the encapsulated gentamicin that was prepared via the precipitation route, even in comparison with the neat antibiotic, especially in the case of the Gram-positive strain Staphylococcus aureus. The gentamicin concentration on the outermost surface and the zeta potential were identified as factors that affected the highest efficiency, as observed in the case of encapsulation via the base-catalyzed process.

Evaluation of gold and silver leaching from printed circuit board of cellphones.

Electronic waste has been increasing proportionally with the technology. So, nowadays, it is necessary to consider the useful life, recycling, and final disposal of these equipment. Metals, such as Au, Ag, Cu, Sn and Ni can be found in the printed circuit boards (PCB). According to this, the aims of this work is to characterize the PCBs of mobile phones with aqua regia; obtaining "reference" values of leaching, to gold and silver, with cyanide and nitric acid, respectively; and study the process of leaching of these metals in alternative leaching with sodium thiosulfate and ammonium thiosulfate. The metals were characterized by digesting the sample with aqua regia for 1 and 2h at 60°C and 80°C. The leaching of Au with a commercial reagent (cyanide) and the Ag with HNO3were made. The leaching of Au and Ag with alternative reagents: Na2S2O3, and (NH4)2S2O3 in 0.1M concentration with the addition of CuSO4, NH4OH, and H2O2, was also studied. The results show that the digestion with aqua regia was efficient to characterize the metals present in the PCBs of mobile phones. However, the best method to solubilize silver was by digesting the sample with nitric acid. The leaching process using sodium thiosulfate was more efficient when an additional concentration of 0.015 and 0.030 M of the CuSO4 was added.

Radiation protection, radiation safety and radiation shielding assessment of HIE-ISOLDE.

The high intensity and energy ISOLDE (HIE-ISOLDE) project is an upgrade to the existing ISOLDE facility at CERN. The foreseen increase in the nominal intensity and the energy of the primary proton beam of the existing ISOLDE facility aims at increasing the intensity of the produced radioactive ion beams (RIBs). The currently existing ISOLDE facility uses the proton beam from the proton-synchrotron booster with an energy of 1.4 GeV and an intensity up to 2 µA. After upgrade (final stage), the HIE-ISOLDE facility is supposed to run at an energy up to 2 GeV and an intensity up to 4 µA. The foreseen upgrade imposes constrains, from the radiation protection and the radiation safety point of view, to the existing experimental and supply areas. Taking into account the upgraded energy and intensity of the primary proton beam, a new assessment of the radiation protection and radiation safety of the HIE-ISOLDE facility is necessary. Special attention must be devoted to the shielding assessment of the beam dumps and of the experimental areas. In this work the state-of-the-art Monte Carlo particle transport simulation program FLUKA was used to perform the computation of the ambient dose equivalent rate distribution and of the particle fluxes in the projected HIE-ISOLDE facility (taking into account the upgrade nominal primary proton beam energy and intensity) and the shielding assessment of the facility, with the aim of identifying in the existing facility (ISOLDE) the critical areas and locations where new or reinforced shielding may be necessary. The consequences of the upgraded proton beam parameters on the operational radiation protection of the facility were studied.

Correspondence between left ventricular 17 myocardial segments and coronary anatomy obtained by multi-detector computed tomography: an ex vivo contribution.

PURPOSE: The aim of this study was to investigate the correspondence between the coronary arterial anatomy and the supplied myocardium based on the proposed American Heart Association (AHA) 17-segment model. METHODS: Six human cadaveric hearts without signs of infarct were selectively injected with colored contrasted gelatin in the three major coronary arteries. After injection, the hearts were scanned by computed tomography (64-detector scanner LightSpeed VCT, GE Healthcare) with a collimation of 64 × 0.625 mm. Reconstructed image data were analyzed in order to evaluate the blood supply of each myocardial segment. RESULTS: Coronary artery territory varies due to anatomy variations. Left anterior descending coronary artery (LAD) was the main vessel responsible for the myocardium blood supply in 11 segments. LAD contributed to the blood supply of all apical segments. Left circumflex (LCx) was the main coronary artery for the infero-anterior wall. Right coronary artery (RCA) contributed in all hearts for the blood supply of infero-septal segments. There was an important overlap between LAD and RCA territories at the infero-septal region and between LAD and LCx territories at the antero-lateral region. CONCLUSIONS: In our experiment, LAD territory was larger than the AHA-proposed 17-segment model. The most specific segments were located at the anterior wall and supplied exclusively by LAD. No specific segment could be exclusively attributed to RCA or to LCx. Sometimes, LCx can be the most important artery for the blood supply of the inferior wall even if the origin of the posterior descending artery is the RCA.