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In this work, two carbohydrate polymers, inulin (I) and maltodextrin (MX), were compared as carrying agents in the spray drying of blueberry juice (BJ). The physicochemical properties and the conservation of the antioxidants content were characterized. Both systems, showed non-agglomerated particles and light-purple color appearance. Powders were subjected to the adsorption of water, and the glass transition temperature (T g ) decreased with the water activity. The evolution of the microstructure in the MX-BJ remained unchanged, while the I-BJ presented an abrupt change from amorphous to crystalline. This was corroborated by scanning electron microscopy (SEM), observing in the I-BJ system, the change from spherical into irregular shape particles. In the conservation of the antioxidants content, the MX-BJ showed a better performance. Anyhow, the performance of both carbohydrate polymers as carrying agents in the spray drying of BJ was effective. [ABSTRACT FROM AUTHOR]

The synthesis of anatase TiO 2 nanoparticles by an acid-assisted sol–gel method at 25 and 80 °C is described. Specifically, acetic acid (AA) was used and the evolution of the anatase phase with the amount of AA was observed. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) both showed that a pure anatase phase was obtained with particle size smaller than 5 nm. Structural refinements and quantitative determination of phase composition was achieved by using the Rietveld method. The particle size distribution became slightly narrower as the amount of AA was increased. Raman spectroscopy showed that when the amount of AA was increased a small amount of brookite was present at the contamination level. The anatase phase was studied by differential thermal analysis (DTA), providing phase stability up to 600 °C. These and other results were discussed in terms of particle size and structure. Likewise, the formation of the anatase phase under these synthesis conditions was explained. [ABSTRACT FROM AUTHOR]

Highlights: [•] The physical properties of pure inulin and inulin–orange juice systems were studied. [•] Glass transition temperature decreases as water was adsorbed. [•] Crystallization was induced by water adsorption and microstructure was observed. [•] Overall appearance was related with morphology developed by microstructure. [•] Results may be useful in predicting shelf stability of food products. [ABSTRACT FROM AUTHOR]

The availability of financial resources in countries with growing economy is limited. For this reason, the acquisition of high cost equipment in each of the institutions dedicated to research is greatly restricted. High resolution transmission electron microscopes (HRTEM) are sophisticated equipment and with high-cost in the market, which are widely used in the characterization of nanomaterials. In this work, we present the remote operation of a HRTEM, discussing some technical details, results, advantages and disadvantages. The remote operation used for this paper was done with a distance between the HRTEM and the remote operator about 660 km. The remote control unit is connected to the Internet 2 with a bandwidth of 10 MB. Access to the operating functions is performed using dedicated software and a VNC connection. For one labor year, there have been analyzed more than 100 samples, obtaining high resolution images, energy dispersive x-ray spectroscopy mappings, diffraction patterns and electron energy loss spectroscopy spectra. Some of these results have been already published in scientific journals. In spite of very good results obtained, some disadvantages may be mentioned, like there are some functions for which the remote operator has not access, such as the IS2 lens, the rebooting of the lenses and obviously the sample exchange. However, the great advantage in this type of operation is that the researchers or students do not need to travel in order to analyze their materials. [ABSTRACT FROM AUTHOR]

Twin wire arc spraying (TWAS) was used to produce an amorphous crystalline Fe-based coating on AISI1018 steel substrate using a commercial powder (140MXC) in order to improve microhardness and wear properties. The microstructures of coating were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) as well as the powder precursor. Analysis in the coating showed the formation of an amorphous matrix with boron and tungsten carbides randomly dispersed. At high amplifications were identified boron carbides at interface boron carbide/amorphous matrix by TEM. This kind of carbides growth can be attributed to partial crystallization by heterogeneous nucleation. These interfaces have not been reported in the literature by thermal spraying process. The measurements of average microhardness on amorphous matrix and boron carbides were 9.1 and 23.85 GPa, respectively. By contrast, the microhardness values of unmelted boron carbide in the amorphous phase were higher than in the substrate, approaching 2.14 GPa. The relative wear resistance of coating was 5.6 times that of substrate. These results indicate that the twin wire arc spraying is a promising technique to prepare amorphous crystalline coatings. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize demographic and occupational variables of cases of upper limb and lower back musculoskeletal injuries. Methodology: In a descriptive, cross-sectional study, we searched and reviewed scientific literature to learn about occupational risk factors associated with musculoskeletal injuries of upper limbs, the lower back and to determine relevant variables. The demographic and occupational variables in musculoskeletal injury cases were obtained from records in the database designed by the National Occupational Health Division at Universidad Nacional de Colombia. Results: We identified 99 records of workers with positive diagnosis of upper limb and lower back musculoskeletal injuries. The female gender and age group between 41 to 50 years reported 60% and 43.43% of the cases of musculoskeletal injuries respectively. The percentage of cases by occupational group for teachers and administrative workers showed a similar distribution of 28.28%. We found that repetitive movements of elbow, wrist, fingers for upper limbs and an extended position for lumbar region are the most common risk factors. In workers, wrist and lower back were the most prominent musculoskeletal injuries. Scoliosis and hyperlordosis were spinal disorders more frequent among participants. The improvement and / or disappearance of symptoms with rest and recurrence or worsening during the work time was the more representative criterion for considering the possible cases of occupational origin of musculoskeletal injuries to upper limbs and lower back. Conclusion: The knowledge of these variables associated with musculoskeletal injuries allows for preventive interventions. [ABSTRACT FROM AUTHOR]

Objectives: We wanted to compare detection of a broad spectrum of human papillomavirus (HPV) types detected in cellular specimens from the vagina and cervix, which could provide information about the potential of each anatomical site for harboring infection. Previous studies have failed to present data on or detect a broad spectrum of HPV genotypes and/or have not carefully sampled the vagina, instead relying on self-collection that is likely contaminated with cervical cells.Study Design: We conducted follow-up study of 353 women who had participated in study of HPV and cervical neoplasia in Costa Rica. We collected paired cervical and vaginal specimens; vaginal specimens were collected from the fornix to minimize cervical contamination. Specimens were tested in a masked fashion for >40 HPV types using a MY09/MY11 PCR method and type-specific dot blot hybridization.Results: The prevalence for any carcinogenic HPV type in vaginal and cervical specimens was similar (P = 0.3). However, the prevalence for any HPV type in vaginal specimens was greater than in cervical specimens (P = 0.0002), primarily due to a twofold increased vaginal prevalence of HPV types of the alpha3/alpha15 phylogenetic species (e.g., HPV61) (P <0.00005).Conclusions: Carcinogenic HPV types appeared to have a similar affinity for vaginal and cervical epithelium, but noncarcinogenic HPV types of the alpha3/alpha15 phylogenetic species may have a tropism for vaginal epithelium. [ABSTRACT FROM AUTHOR]

• Two NiMo/Al 2 O 3 catalysts holding different structural arrangement (two-dimensional and three-dimensional) were prepared. • The required area for the distribution of active phase structured as two layers on NiMoS 2 is around 130 m2 /g of catalyst. • Higher sulphidation degree and the presence of well-dispersed NiMoS 2 nanoparticles on NiMo/OMA catalyst is presented. Ordered mesoporous alumina (OMA), and commercial non ordered mesoporous alumina (CMA) were used as support to synthesize NiMo catalysts with a metal loading of 16%Wt. OMA synthesis was made using Pluronic (P123) as structure directing agent, and ethanol as a solvent. The physical and chemical properties of the supports and catalysts were characterized by XRD, nitrogen physisorption, X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), acidity of support was studied by n-butylamine adsorption followed by FTIR and catalytic performance was evaluated by hydrodesulphurization of dibenzothiophene (DBT) reaction. Main difference of supports is a two-dimensional arrangement of pores on OMA support and a three-dimensional arrangement for CMA. OMA support has more surface area available to disperse Mo and Ni species than the CMA material, besides OMA present slight acidity on its surface, and these characteristics of support leaded to obtain a NiMoS 2 active phase better structured to present higher activity for DBT hydrodesulphurization and higher selectivity for direct desulfurization than the obtained for CMA supported catalyst, despite CMA presented interconnected pores and higher pore diameter. [ABSTRACT FROM AUTHOR]

The concentration levels of trace metals of toxicological importance were evaluated in the total suspended particles (TSP) and particulate matter smaller than 2.5 μm (PM 2.5 ) collected in the Metropolitan Area of Monterrey (MAM) in Mexico. Samples were characterized by inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with an energy-dispersive spectroscopy system (SEM-EDS). In addition, the data were statistically treated by the methodology of Pearson Correlation (PC) and Principal Components Analysis (PCA) to identify the possible emitting sources. Surface analysis of the particulate matter (PM) by XPS revealed that the most abundant elements were Ca, Al, Na, Zn, Cu and Mg. The deconvolution of the Ca 2p , Zn 2p and Cu 2p signals showed that the main contributors were CaCO 3 , ZnO and Cu/Cu 2 O, respectively. The bulk analysis of the PM by ICP-AES showed Fe, Cu and Zn as the most abundant elements. Fe-rich particles presented two different morphologies: the prismatic particles were associated with a natural origin, while the spherical particles with anthropogenic sources. The Zn and Cu were predominantly observed in the sampling stations with high vehicular traffic, and the emitting sources were associated with the burning of fuels from automobiles and the wear of the tires and brakes. The highest concentration of Pb was detected in the sampling station located near the industrial zones, and its cause was associated with the ceramic and glass industries, the burning of fuel oil in power plants and the production of lead-based batteries for automobiles. [ABSTRACT FROM AUTHOR]

Total suspended particles (TSP) and particles smaller than 2.5 μm (PM 2.5 ) were collected at four sites in the metropolitan area of Monterrey (MAM) in Mexico. The samples were characterized by X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscopy (SEM). In order to determine the possible sources of emissions of atmospheric particulate matter, a principal component analysis (PCA) was performed. The XRD results showed that the major crystalline compounds found in the TPS were CaCO 3 and SiO 2 ; while in the PM 2.5 CaSO 4 was found. The XPS analysis showed that the main elements found on the surface of the particles were C, O, Si, Ca, S, and N. The deconvolution carried out on the high-resolution spectra for C 1s , S 2p and N 1s , showed that the aromatics, sulfates and pyrrolic-amides were the main groups contributing to the signal of these elements, respectively. The C-rich particles presented a spherical morphology, while the Ca- and Si-based particles mostly showed a prismatic shape. The PCA analysis together with the results obtained from the characterization techniques, suggested that the main contributors to the CaCO 3 particles collected in the PM were most probably produced and emitted into the atmosphere by local construction industries and exploitation of rich-deposits of calcite. Meanwhile, the SiO 2 found in the MAM originated from the suspension of geological material abundant in the region, and the carbon particles were mainly produced by the combustion of fossil fuels. [ABSTRACT FROM AUTHOR]

Abstract: In this research, some Al-based composites reinforced with silica nanoparticles were fabricated using mechanical milling and processing by powder metallurgy. Density, morphology evolution, hardness and strength of the composites were studied as a function of milling time and additive concentration. Microstructural evidence reveals that milling conditions generated a uniform dispersion of nanoparticles in the Al matrix. Noticeable matrix grain refinement was induced by the milling process. An optimum mechanical response was reached with small amounts of reinforcement nanoparticles complemented with medium milling intensities. These manufacturing conditions allowed to achieve an improvement of mechanical properties compared with the reference material (pure milled Al and un-milled composites processed under the same conditions). On the other hand, an adverse effect was observed with longer milling time and higher additive concentration. [Copyright &y& Elsevier]

Background: The present multicentre study was aimed at determining the effect of preoperative atrial fibrillation (preop-AF) as stroke risk factor in coronary artery bypass graft surgery (CABG) during the perioperative period. Methods: Patients undergoing isolated CABG surgery were enrolled from 21 Spanish centers. Baseline variables related with perioperative stroke risk were recorded and analysed. The Northern New England Cardiovascular Disease Study Group (NNECVDSG) stroke risk schema was used to stratify stroke risk and compare predicted vs observed neurologic outcomes in this study. Results: 26347 patients were enrolled in the study. Prevalence of preop-AF was 4.2%, and was associated significantly with major cardiovascular comorbidities. The stroke rate was 1.38% (365 strokes), and it was slightly higher for patients with preop-AF vs non preop-AF, 1.82% vs 1.36%, p = 0.2. NNECVDSG schema showed good predictive ability calculating the area under the receiver operating characteristic curve (c-statistic 0.696; 95% CI 0.668 to 0.723). To investigate the associations of baseline preoperative variables with perioperative CABG-stroke a logistic regression model was performed. Preop-AF impact on perioperative stroke was lower that other variables. Preop-AF did not show an adverse impact in the quartiles groups according to NNECVDSG Stroke Risk Index. Conclusion: Risk of perioperative stroke in isolated CABG surgery patients is not significantly increased by preop-AF. [ABSTRACT FROM AUTHOR]

Background: Three-dose regimens for human papillomavirus (HPV) vaccines are expensive and difficult to complete, especially in settings where the need for cervical cancer prevention is greatest.Methods: We evaluated the vaccine efficacy of fewer than three doses of the HPV16/18 vaccine Cervarix in our Costa Rica Vaccine Trial. Women were randomly assigned to receive three doses of the HPV16/18 vaccine or to a control vaccine and were followed for incident HPV16 or HPV18 infection that persisted in visits that were 10 or more months apart (median follow-up 4.2 years). After excluding women who had no follow-up or who were HPV16 and HPV18 DNA positive at enrollment, 5967 women received three vaccine doses (2957 HPV vaccine vs 3010 control vaccine), 802 received two doses (422 HPV vs. 380 control), and 384 received one dose (196 HPV vs. 188 control). Reasons for receiving fewer doses and other pre- and post-randomization characteristics were balanced within each dosage group between women receiving the HPV and control vaccines.Results: Incident HPV16 or HPV18 infections that persisted for 1 year were unrelated to dosage of the control vaccine. Vaccine efficacy was 80.9% for three doses of the HPV vaccine (95% confidence interval [CI] = 71.1% to 87.7%; 25 and 133 events in the HPV and control arms, respectively), 84.1% for two doses (95% CI = 50.2% to 96.3%; 3 and 17 events), and 100% for one dose (95% CI = 66.5% to 100%; 0 and 10 events).Conclusion: Four years after vaccination of women who appeared to be uninfected, this nonrandomized analysis suggests that two doses of the HPV16/18 vaccine, and maybe even one dose, are as protective as three doses. [ABSTRACT FROM AUTHOR]

Objective: We investigated coinfection patterns for 25 human papillomavirus (HPV) types and assessed the risk conferred by multiple HPV types toward cervical disease.Methods: Sexually active women (n=5,871) in the NCI-sponsored Costa Rica HPV Vaccine Trial's prevaccination enrollment visit were analyzed. Genotyping for 25 HPVs was performed using SPF(10)/LiPA(25). We calculated odds ratios (ORs) to assess coinfection patterns for each genotype with 24 other genotypes. These ORs were pooled and compared with pair-specific ORs to identify genotype combinations that deviated from the pooled OR. We compared risk of CIN2+/HSIL+between multiple and single infections and assessed additive statistical interactions.Results: Of the 2478 HPV-positive women, 1070 (43.2%) were infected with multiple types. Multiple infections occurred significantly more frequently than predicted by chance. However, this affinity to be involved in a coinfection (pooled OR for 300 type-type combinations=2.2; 95% confidence interval [CI]=2.1-2.4) was not different across HPV type-type combinations. Compared with single infections, coinfection with multiple α9 species was associated with significantly increased risk of CIN2+(OR=2.2; 95% CI=1.1-4.6) and HSIL+(OR=1.6; 95% CI=1.1-2.4). However, disease risk was similar to the sum of estimated risk from individual types, with little evidence for synergistic interactions.Conclusions: Coinfecting HPV genotypes occur at random and lead to cervical disease independently. [ABSTRACT FROM AUTHOR]

Context: Viruslike particle human papillomavirus (HPV) vaccines were designed to prevent HPV infection and development of cervical precancers and cancer. Women with oncogenic HPV infections might consider vaccination as therapy.Objective: To determine whether vaccination against HPV types 16 and 18 increases the rate of viral clearance in women already infected with HPV.Design and Setting: Phase 3, masked, community-based randomized trial conducted in 2 provinces of Costa Rica.Participants: A total of 2189 women aged 18 to 25 years who were recruited between June 2004 and December 2005. Participants were positive for HPV DNA at enrollment, had at least 6 months of follow-up, and had follow-up HPV DNA results.Intervention: Participants were randomly assigned to receive 3 doses of a bivalent HPV-16/18 L1 protein viruslike particle AS04 candidate vaccine (n = 1088) or a control hepatitis A vaccine (n = 1101) over 6 months.Main Outcome Measures: Presence of HPV DNA was determined in cervical specimins by a molecular hybridization assay using chemiluminescence with HPV RNA probes and by polymerase chain reaction using SPF10 primers and a line probe assay detection system before vaccination and by polymerase chain reaction after vaccination. We compared rates of type-specific viral clearance using generalized estimating equations methods at the 6-month visit (after 2 doses) and 12-month visit (after 3 doses) in the 2 study groups.Results: There was no evidence of increased viral clearance at 6 or 12 months in the group who received HPV vaccine compared with the control group. Clearance rates for HPV-16/18 infections at 6 months were 33.4% (82/248) in the HPV vaccine group and 31.6% (95/298) in the control group (vaccine efficacy for viral clearance, 2.5%; 95% confidence interval, -9.8% to 13.5%). Human papillomavirus 16/18 clearance rates at 12 months were 48.8% (86/177) in the HPV vaccine group and 49.8% (110/220) in the control group (vaccine efficacy for viral clearance, -2.0%; 95% confidence interval, -24.3% to 16.3%). There was no evidence of a therapeutic effect for other oncogenic or nononcogenic HPV categories, among women receiving all vaccine doses, among women with single infections, or among women stratified by the following entry variables: HPV-16/18 serology, cytologic results, HPV DNA viral load, time since sexual debut, Chlamydia trachomatis or Neisseria gonorrhoeae infection, hormonal contraceptive use, or smoking.Conclusion: In women positive for HPV DNA, HPV-16/18 vaccination does not accelerate clearance of the virus and should not be used to treat prevalent infections.Trial Registration: clinicaltrials.gov Identifier: NCT00128661. [ABSTRACT FROM AUTHOR]

The potential of KIT-6 as support for hydrodesulfurization (HDS) catalysts has been demonstrated in several works. Main advantage of KIT-6 consists of more than double of surface area that is accessible for large molecules (pore diameter above 6 nm). In the synthesis of KIT-6 prevails the use of tetraethyl orthosilicate (TEOS) as silicon source, being the requirement of this alkoxide one of the main hindrance to consolidate the use of this support on industry. This work presents a green synthesis of KIT-6 and Ti-modified KIT-6 obtained from water-glass, which were used to synthesize CoMo catalysts with metal loading of 16% wt, through incipient impregnation method assisted by ultrasound. Performance of these catalysts on HDS of DBT was compared for equivalent supports synthesized from TEOS and results demonstrate that the use of water-glass for support synthesis does not affect significantly the catalytic activity, allowing thus its use for the design of HDS commercial catalysts. Image 1 • The CoMo catalysts supported on a 3D mesoporous silica network (KIT-6) were prepared. • The use of KIT-6 allows to improve the dispersion degree of active metals. • Na 2 SiO 3 as precursor have severals advantages, is cheap, easy to handle, water unreactive, and environmentally friendly. • The addition of TiO 2 was evaluated on the active phase dispersion, and its performance in the HDS of DBT compared. [ABSTRACT FROM AUTHOR]

The development and optimization of methodologies to generate magnetite nanoparticles is currently an innovation topic. For a desired application such as arsenic removal from waste water, the generation of these nanostructures with specific microstructural properties is determinant. Therefore, it is necessary to understand the phenomenon during the nanoparticles formation process. Thus, in this work it is reported the influence of synthesis parameters of AACVD technique on the formation of magnetite nanoparticles. Parameters were according to: (1) synthesis temperature, (2) tubular reactor diameter, (3) concentration of the precursor solution and type of solvent, (4) carrier gas flow and (5) solvent type in the collection process. The effect of these synthesis parameters on the morphology, size and microstructure are discussed in detail and related with the mechanism of formation of the particles. Theoretical simulations were performed on two of these parameters (1 and 4). The microstructure and surface morphology of the different nanostructures obtained were characterized by field emission scanning electron and transmission electron microscopy. Subsequently two materials, were selected for further microstructural analysis. Finally, to determine the removal efficiency in the two materials the arsenic adsorption was evaluated. A major contribution of this work was the calculation of the number of spherical particles formed from a single drop of precursor solution. This calculation matched with the value found experimentally. [ABSTRACT FROM AUTHOR]

Nowadays, mesoporous magnetite nanoparticles are an important class of new nanomaterials which occupy a valuable position in materials science. Owing to their several advantages over bulk magnetite and particularly with respect to higher adsorption capacity, there is a growing interest towards the use of these materials for the adsorptive removal of a variety of contaminants, including organic dyes from wastewater. Through aerosol assisted chemical vapor deposition (AACVD) technique is possible to synthesize spherical hollow nanoparticles with external diameter from 50 to 500 nm, composed of a shell of crystallites smaller than 30 nm. In the AACVD method, the structural morphology of resultant nanoparticles strongly depends on the starting precursors and operating conditions. Some advantages of this technique are the high production rate, continuous operation, use of relatively simple equipment, easy doping and the possibility to scale the process industrially. Therefore, in order to understand the formation of magnetite nanoparticles by AACVD, theoretical simulations were performed on two important steps of the synthesis: (i) temperature and carrier gas flow distribution inside of tubular reactor, and (ii) the distribution of molar concentration of the precursor in the synthesis process. Reaction kinetics of the precursor was studied to determine Arrhenius parameters. Activation energy and pre-exponential factor were calculated experimentally from thermal analysis, these values were used in the calculation of reactants and product concentration distribution inside of the tubular reactor. Results from the simulation were compared with those obtained from the experiments. [ABSTRACT FROM AUTHOR]

Abstract: New nanotechnology alternatives and methodologies have been developed in order to overcome the limitations of conventional techniques for metal ions removal from water. Currently, the removal of heavy metals requires multiple steps which include the separation and post-treatment of the generated sludge. Usually, this sludge is composed of dangerous environmental pollutants mixed with the material used for removing the metal ion. Thus, the removal of these metals becomes a challenging task. Herein we report the synthesis of magnetite nanoparticles with high specific area by the aerosol assisted chemical vapour deposition method. Deposition temperature were fixed at 450°C and a mixture of Ar–air were used as a carrier gas, a flow of 1.0 and 0.015Lmin−1 were used for Ar and air, respectively. The precursor solution was a dilution of Fe (II) chloride in methanol, with different concentration 0.01, 0.05 and 0.1moldm−3. The crystalline structure of the nanoparticles was characterized by grazing incidence X-ray diffraction. Morphology and microstructure were analyzed by field emission scanning electron microscopy, scanning probe microscopy and transmission electron microscopy. Magnetic properties were evaluated with a vibrating sample magnetometer and specific area was measured by the Brunauer–Emmett–Teller method. To determine the removal efficiency of arsenic ion from water, several tests were carried out at six exposition times 1, 3, 5, 10, 20 and 30min. Results showed high removal efficiency, more than 99%, in less than 1min. [Copyright &y& Elsevier]