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An initial mixture of raw materials (batch) typically used for the manufacture of conventional soda-lime float glass was subjected to a mechanical activation process for 30 or 60 minutes in a planetary ball mill. An intensification of the chemical reactivity of the batch, which was directly related with the increase in the milling time, was observed. This accelerated the chemical reactions that took place during the batch melting process between sodium, calcium and magnesium carbonates and other components of the mixture, which happened at significantly lower temperatures with respect to the batch without mechanical activation. The heat of fusion of the batch, estimated using a methodology previously reported in the literature, indicated that the mechanical activation given to the initial mixture of raw materials decreased the energy consumed during the batch melting. This was also evidenced by a decrease in the temperature at which the release of CO2 ended, which was considerably larger than that previously reported in the literature based solely on the decrease in the particle size of a batch of similar composition achieved by dry sieving.
An alternative method for the standardless quantitative x-ray diffraction analysis of mixtures of inorganic crystalline phases proposed in the literature several years ago is presented. Our method requires only previously calculated μ*i values from tabulated data for all phases present in the mixtures. It does not require either the determination of calibration constants or the use of external standards, but it does require that the number of analyzed mixtures is larger than or equal to the number of phases present in them, and that the chemical composition of the mixtures are significantly different from each other. The integrated intensities of the chemically pure phases are estimated by a least-squares procedure from XRD data obtained from the mixtures. The method was tested against data published in the literature, with good results. Finally, a general expression for the “Normalized Height Law” proposed on an empirical basis by other researchers, has been theoretically derived.
Based on wettability and reaction interfaces previously reported, as well as on thermodynamic considerations, a likely mechanism has been proposed for the chemical interaction taking place at the metal/ceramic interface during wettability experiments carried out by the so-called “sessile drop” method. The experiments involved three Ag-Cu-based brazing alloys [Cusil (Ag-28wt.%Cu), Cusil-ABA (Ag-34.6wt.%Cu-1.58wt.%Ti) and Incusil-ABA (Ag-26.6wt.%Cu-12.4wt.%In-0.89wt.%Ti)] and as polished and pre-oxidized pressure-less sintered silicon carbide (PLS-SiC), with a total holding time of 90 minutes at 850 °C, under a Zr sponge-gettered vacuum of 10-4/10-5 Torr.
C-mannosylation was recently identified in the thrombospondin-related anonymous protein (TRAP) from Plasmodium falciparum salivary gland sporozoites. A candidate P. falciparum C-mannosyltransferase (PfDPY-19) was demonstrated to modify thrombospondin type 1 repeat (TSR) domains in vitro, exhibiting a different acceptor specificity than their mammalian counterparts. According to the described minimal acceptor of PfDPY19, several TSR domain-containing proteins of P. falciparum could be C-mannosylated in vivo. However, the relevance of this protein modification for the parasite viability remains unknown. In the present study, we used CRISPR/Cas9 technology to generate a PfDPY19 null mutant, demonstrating that this glycosyltransferase is not essential for the asexual blood development of the parasite. PfDPY19 gene disruption was not associated with a growth phenotype, not even under endoplasmic reticulum-stressing conditions that could impair protein folding. The data presented in this work strongly suggest that PfDPY19 is unlikely to play a critical role in the asexual blood stages of the parasite, at least under in vitro conditions.
In the present study, aiming to control the setting reaction and to increase the strength of hydroxyapatite-based biocements, gelatin, citric acid and malonic acid, and combinations of them, were used as binders. The mechanical strength of the developed biocements was evaluated after 1 to 15 days of exposure (aging) to air with 100% relative humidity at 37-40 °C. Especially for the case of gelatin, the mechanical properties of the biocements increased as a function of aging time in the humid environment. In this case, the standard compressive strength increased from ∼19 to ∼40 MPa, while the diametral compressive strength increased from ∼2 to ∼12 MPa, between day 1 and day 15 of aging. These values are similar to those reported in the past for HAp-containing biocements added with a variety of organic or inorganic binders. However, the resulting setting times were too long. Thus, it was proposed that crosslinking of gelatin by a suitable chemical agent during the application of the prepared HAp-based biocements could be a potential way to control their handling and setting characteristics, while preserving their good mechanical properties, good biocompatibility, and good solubilization characteristics in the presence of biological fluids.
Solution-processed metal oxide electronics on flexible substrates can enable applications from military to health care. Due to limited thermal budgets and mismatched coefficients of thermal expansion between oxides and substrates, achieving good performance in solution-processed oxide films remains a challenge. Additionally, the use of traditional photolithographic processes is incompatible with low-cost, high-throughput roll-to-roll processing. Here, we demonstrate solution-deposited oxide thin film transistors (TFTs) on a shape memory polymer substrate, which offers unique control of final device shape and modulus. The key enabling step is the exposure of the precursor film to UV-ozone through a shadow mask to perform patterning and photochemical conversion simultaneously. These TFTs exhibit mobility up to 160 cm2/(V s), subthreshold swing as low as 110 mV/dec, and threshold voltage between −2 and 0 V, while maintaining compatibility with a flexible form factor at processing temperatures below 250 °C.
CHD is becoming an increasing priority worldwide, as it is one of the main causes of death in low- and middle-income countries lately. This study aims to evaluate the association between beverage consumption patterns and the risk of CHD among Mexican adult population. We performed a cross-sectional analysis using data from 6640 adults participating in the Health Workers’ Cohort Study. Factor analysis was performed to identify beverage patterns using sex-specific Framingham prediction algorithms to estimate CHD risk. The prevalence of moderate to high CHD risk was 17·8 %. We identified four major beverage consumption patterns, which were categorised as alcohol, coffee/tea, soft drinks and low-fat milk. We observed a lower risk of CHD (OR=0·61; 95 % CI 0·46, 0·80; and OR=0·58; 95 % CI 0·43, 0·79, respectively) among participants in the upper quintile of alcohol or low-fat milk consumption compared with those in the bottom quintile. In contrast, a higher consumption of soft drinks was positively associated with CHD risk (OR=1·64; 95 % CI 1·21, 2·20) when compared with other extreme quintiles. Finally, coffee/tea consumption was not significantly associated with CHD risk. Our findings suggest that a beverage pattern characterised by a higher intake of sugar-sweetened beverages may be associated with an increased risk of CHD among the Mexican adult population, whereas patterns of moderate alcohol intake and low-fat milk may be associated with a reduced risk.
In this study, based on the collection process, three-dimensional aligned fiber scaffolds from gelatin and zein protein were manufactured using Forcespinning®. The homogeneous blending of gelatin:zein (1:4) showed improved tensile and good hydrophobic properties (water contact angle of 115 °C). Cell viability, adhesion, proliferation, and drug release were measured. The cell viability was studied with human fibroblasts and a low cytotoxic effect was observed. Berberine drug release was measured and sustained release rate was observed over 15 days. The morphologic features, prolonged drug release, and cytotoxicity results suggest that these fibers could be appropriate for drug delivery and tissue engineering applications.
Hydroxyapatite [HAp, Ca5(PO4)3(OH)] was synthesized by chemical precipitation, using H3PO4 and Ca(OH)2 as chemical precursors. The precursors were slowly mixed in suitable proportions aiming to obtain Ca/P molar ratios of 1.5, 1.67 or 2.0 in the reacting suspension. This was followed by 21.5 h of aging. Both reaction and aging stages were carried out under an atmosphere of still ambient air and under continuous stirring, either at room temperature, 60 or 90 °C. The precipitates were characterized by ICP-AES and XRD. The results suggested that the most suitable Ca/P molar ratio for the production of pure phase HAp is Ca/P = 1.67, as long as the initial Ca(OH)2 particle size and/or the suspension pH are carefully controlled, especially when the synthesis is carried out above room temperature.
Glasses and glass-ceramics of the system Diopside [D, CaMgSi2O6] - Fluorapatite [FAp, Ca5(PO4)3F] were synthesized and characterized. The studied theoretical phase compositions were (wt%): 1) 70% D-30% FAp, 2) 60% D-40% FAp and 3) 80% D-20% FAp. The glass-ceramics were synthesized by isothermal treatment of the corresponding parent glasses at either 800, 900 or 1000 °C, with holding times of either 30 min, 2 h or 5 h at high temperature. The in vitro bioactivities of all materials were tested in Kokubo’s Simulated Body Fluid (SBF), for 21 days at pH = 7.4 and 37 °C. All materials were characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM/EDS). In all cases, the in vitro bioactivity increased with decreasing crystallization degree in the materials, which was likely due to an inhibitory effect of the structural changes occurring during thermal treatment of the glasses. This was more accentuated for long thermal treatments. After 21 days of soaking in the SBF, an apatite-like surface layer, with a Ca/P molar ratio close to 1.67, was formed in the case of the parent glass of composition 2. This was attributed to an enhancing effect of so-called “phase separation” phenomenon that took place during the synthesis of that particular glass. Lastly, the MgO content of the glasses made no clear difference on their in vitro bioactivity.
The Spanish National Network (REDETS) is a group of eight agencies, units and services, depending on National and Regional Governments that coordinate their work within a common methodological framework, guided by the principles of mutual recognition and cooperation. The necessity of considering a Quality Management System has been detected and, consequently, a common tool for all the members needs to be developed. We describe in this study the process to achieve that goal.
Based on both a review of previous literature and the proposal for a self-evaluating tool, a group of experts from each agency through consensus have developed a tool for self-evaluation in Health Technology Assessment (HTA) agencies. Through the structure described in the handbook of the Andalusian Agency for Healthcare Quality (ACSA), each standard should have a statement or proposal that needs to also include evidence or good practices, and the corresponding evaluation questions. In separate workgroups, the definition of these proposals, evidence and evaluation questions were developed. One face-to-face meeting and two meetings via teleconference were necessary to achieve a final document with all the quality standards.
From a proposed structure of sixty-six standards, the titles, definitions, statements and evidence as well as good practices and evaluation questions were established in workgroups with consensus among all of the members (1 - 3). The final version of the self-assessment tool was composed of sixty-eight standards, grouped in twelve quality criteria structured in four dimensions: I Responsibility, II Clients and Stakeholders, III Production Process, and IV Resources.
Quality management requires an evaluation tool and this version, based on a systematic review and consensus, is a useful and practical instrument for developing a handbook by each member of REDETS. An online version of the tool is in process of development.
Early awareness and alert systems (EAAS) try to anticipate the impact of new technologies in the healthcare systems. Spain, which has a decentralized health system with public provision and universal health coverage, has been a pioneer in establishing EAAS activities. From 2006 a network of regional agencies coordinated EAAS activities. Taking into account the individual agencies scarce resources and in order to improve efficiency, this collaboration decided to distribute tasks when identifying and early assessment of new and emerging health technologies. The aim was to inform the common benefit package of the Spanish public health system.
Four out of eight Spanish Health Technology Assessment (HTA) agencies had EAAS in Spain (AETS-Carlos III Institute; AETSA-Andalusia; Avalia-t-Galicia; Osteba-Basque Country). Each agency has taken care of different sources for the identification of new and emerging non-drug health technologies: industry and innovator contacts, health expert networks, mass media and EAAS databases. Members of the network used the same filtration criteria to reach the final list. The system will run in parallel to a biannual identification process in major databases.
In 2016, the network identified and filtered sixty-three technologies: ten by mass media; five by health experts; thirty-five other EAAS and thirteen by direct contact with industry and innovators. Main represented specialties were: endocrinology (seven); gynecology and obstetrics (six); cardiology and cardiac surgery (five); emergency medicine (four); dermatology (three) and pneumology (three). Technologies were grouped by specialty in order to inform the different commissions that discuss inclusion in the Spanish Benefit Package. Specialty monographs will be published to inform stakeholders.
The approach is feasible, and increases the capacity of individual agencies to address the needs of the national and regional systems by improving their efficiency. There is a need to previously define the methods and the criteria that will be used for the identification and filtration.
Cordierite (Mg2Al4Si5O18), Mullite (Al4+2xSi2-2xO10-x) and Cordierite-Mullite ceramic materials were obtained from a stoichiometric mixture of coal fly ash (CFA) as a source of SiO2 and Al2O3, plus high-purity MgO and Al2O3. The starting stoichiometric mixtures were homogenized, and then uniaxially pressed, cold isostatically pressed, and sintered at 1200-1600 °C for 2-5 h. The sintered materials were characterized by X-ray diffraction, scanning electron microscopy, Vickers microhardness, density and four-point flexural strength. In general, the desired phases tended to form in the composites at temperatures of 1350 or 1400 °C, with a considerable amount of glassy phase developing from 3 h onwards at one of those two temperatures, depending on the composite composition. The microstructure of the composites consisted of a matrix of Cordierite and interwoven needles of Mullite. The bulk density decreased, while the flexural strength and the Vickers microhardness increased with increasing nominal content of Mullite in the composites. A synergistic effect taking place between Cordierite and Mullite enhances the mechanical properties of the composites.
Ladle refining plays a key role in achieving the quality of the steel since in this reactor temperature and chemical composition is adjusted, elimination of non-metallic inclusions is performed, and also deoxidation and desulphurization are operations taking place in the refining process. Specifically, the metal-slag mass exchanges have not received much attention through scientific studies. In this work, a rigorous study on the mass exchange between metal and slag is presented through a scaled water physical model. In the model, thymol (playing the role of a solute such as sulfur) is added to the water (playing the role of steel) and silicon oil (playing the role of slag) picks up the thymol, while the ladle is agitated with the central injection of gas. The evolution of thymol concentration in time was measured. Also, a mathematical model was developed and cast into the commercial CFD code Fluent Ansys to represent the fluid flow phenomena and the mass transfer through the solution of the continuity equation, the turbulent momentum conservation equations and the species mass conservation equation. There is a good agreement between the measured and the computed results regarding the thymol concentration evolution in water and consequently the mathematical model was validated regarding the mass species metal-slag exchanges and it may be used to study metal-slag exchanges in the steel ladle such as deoxidation or desulphurization.
Leishmaniasis is one of the world's most neglected diseases, and it has a worldwide prevalence of 12 million. There are no effective human vaccines for its prevention, and treatment is hampered by outdated drugs. Therefore, research aiming at the development of new therapeutic tools to fight leishmaniasis remains a crucial goal today. With this purpose in mind, we present 20 arylaminoketone derivatives with a very interesting in vitro and in vivo efficacy against Trypanosoma cruzi that have now been studied against promastigote and amastigote forms of Leishmania infantum, Leishmania donovani and Leishmania braziliensis strains. Six out of the 20 Mannich base-type derivatives showed Selectivity Index between 39 and 2337 times higher in the amastigote form than the reference drug glucantime. These six derivatives affected the parasite infectivity rates; the result was lower parasite infectivity rates than glucantime tested at an IC25 dose. In addition, these derivatives were substantially more active against the three Leishmania species tested than glucantime. The mechanism of action of these compounds has been studied, showing a greater alteration in glucose catabolism and leading to greater levels of iron superoxide dismutase inhibition. These molecules could be potential candidates for leishmaniasis chemotherapy.
The flow in a split cylinder with each half in exact counter rotation is studied numerically. The exact counter rotation, quantified by a Reynolds number
based on the rotation rate and radius, imparts the system with an
symmetry (invariance to azimuthal rotations as well as to an involution consisting of a reflection about the mid-plane composed with a reflection about any meridional plane). The
symmetric basic state is dominated by a shear layer at the mid-plane separating the two counter-rotating bodies of fluid, created by the opposite-signed vortex lines emanating from the two endwalls being bent to meet at the split in the sidewall. With the exact counter rotation, the additional involution symmetry allows for steady non-axisymmetric states, that exist as a group orbit. Different members of the group simply correspond to different azimuthal orientations of the same flow structure. Steady states with azimuthal wavenumber
(the value of
depending on the cylinder aspect ratio
) are the primary modes of instability as
are varied. Mode competition between different steady states ensues, and further bifurcations lead to a variety of different time-dependent states, including rotating waves, direction-reversing waves, as well as a number of slow–fast pulse waves with a variety of spatio-temporal symmetries. Further from the primary instabilities, the competition between the vortex lines from each half-cylinder settles on either a
steady state or a limit cycle state with a half-period-flip spatio-temporal symmetry. By computing in symmetric subspaces as well as in the full space, we are able to unravel many details of the dynamics involved.
The nonlinear dynamics of the flow in a differentially rotating split cylinder is investigated numerically. The differential rotation, with the top half of the cylinder rotating faster than the bottom half, establishes a basic state consisting of a bulk flow that is essentially in solid-body rotation at the mean rotation rate of the cylinder and boundary layers where the bulk flow adjusts to the differential rotation of the cylinder halves, which drives a strong meridional flow. There are Ekman-like layers on the top and bottom end walls, and a Stewartson-like side wall layer with a strong downward axial flow component. The complicated bottom corner region, where the downward flow in the side wall layer decelerates and negotiates the corner, is the epicentre of a variety of instabilities associated with the local shear and curvature of the flow, both of which are very non-uniform. Families of both high and low azimuthal wavenumber rotating waves bifurcate from the basic state in Eckhaus bands, but the most prominent states found near onset are quasiperiodic states corresponding to mixed modes of the high and low azimuthal wavenumber rotating waves. The frequencies associated with most of these unsteady three-dimensional states are such that spiral inertial wave beams are emitted from the bottom corner region into the bulk, along cones at angles that are well predicted by the inertial wave dispersion relation, driving the bulk flow away from solid-body rotation.
We present a bi-dimensional Fourier analysis of near-infrared images of KPG 404 (NGC 5394/95). The 2D Fourier analysis shows that NGC 5394 is a H2β galaxy in the DP classification (Block & Puerari 1999). In contrast, NGC 5395 displays a very complex structure which needs a number of Fourier coefficients to be explained. A tightly wound m = 1 (DP class H1α) is the main structure, but other m = 1 and m = 2 coefficients (suggesting spiral arm modulation) are also present in the Fourier spectra. The complex structure of NGC 5395 also suggests a strong interaction in the pair. The m = 1 coefficients can represent a pseudo ring-type structure, resulting of a collision rather than a grazing passage. We conclude that the most probable scenario of the interaction in this pair should take into account a crossing of NGC 5394 through the disk of NGC 5395.
We present near infrared observations in J, H and K' pass-bands of the interacting pair of galaxies KPG 404 (NGC 5394/95). We calculate total magnitudes, surface brightnesses and colour profiles. We present the growth curve to compare our photometry against earlier works in which circular aperture estimations were published. We also perform a structural (disk + bulge) analysis to get insight on the morphology of the pair. The disk+bulge fit shows that NGC 5394 (KPG 404A) is more compact than normal galaxies, while NGC 5395 (KPG 404B) is less concentrated. This suggests an interacting scenario in which NGC 5394 passes through the disk of NGC 5395 (a Cartwheel-type collision), rather than a passage as M51-type pairs.