Hazardous materials like barium and lead present in discarded Cathode Ray Tubes, CRT's, may represent a big problem to the environment if they are not properly disposed. In the present study, ...solidification/stabilization of crushed waste CRT (CRT glass particles), through a calcined kaolin base-geopolymer as metal-immobilizer is presented. Two different compositions of raw materials using 5, 10, and 20% wt of CRT glass particles were studied. The geopolymers were analyzed by XRD, SEM, TG-DTA/DSC, FTIR, leaching tests. The microhardness of coatings on mild steel was tested. The results and the differences in properties are explained based on the microstructure evolution of the geopolymer with CRT glass particles. The results showed that low alkaline medium was effective in the encapsulation of toxic heavy metals from the CRT glass even though they were used as coatings on mild steel samples.
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•Geopolymers encapsulate CRT glass particles efficiently.•Toxic heavy metals are successfully immobilized in calcined kaolin based geopolymer.•The CRT glass particles are well anchored in a dense matrix.•Leaching testing showed values of heavy metals within the range of Standards.
The aim of this research was to study the feasibility of producing sintered nepheline glass-ceramic through a fast firing route. The thermal behaviour of the original glass was analyzed by mean of ...differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The microstructural analysis of glass-ceramic materials was carried out by field-emission scanning electron microscopy (FE-SEM). The results showed that the studied wastes are able to produce a glass and glass-ceramic materials through a sinter-crystallisation process, 100μm being the critical glass particle size. Glass-ceramics are composed of residual glassy phase and crystalline phases such as nepheline (NaAlSiO4), augite (Ca, Na)(Mg, Fe, Al)(Si, Al)2O4 and a solid solution belonging to the melilite group (Ca, Na)(Al, Mg, Fe,)(Si, Al)2O7. In a first evaluation, water absorption (0.02%) and bending strength (71MPa) of glass-ceramic achieved after thermal treatment at 1100°C/5min suggest that sintered glass-ceramics can be easily produced from coal fly ash and metallurgical slag wastes by a fast-firing cycle and they are extremely serviceable for outdoor flooring and wall cladding.
•Crystallisation in nepheline-based glass (CEC) occurs through a surface mechanism.•A particle size<100μm is the most efficient for a sinter-crystallisation process.•CEC glass is easily adapted to the fast-firing cycle use in ceramic tile manufacture.•CEC glass-ceramics are composed of nepheline, melilite s.s. and augite.•CEC glass-ceramics show technological properties suitable for use in construction.
ZnO nanospheres were synthesised and then deposited by both single- and double-fire fast processes on as-prepared ceramic substrates. The photocatalytic degradation of resazurin ink was tested under ...UV light. The single-fired samples did not show any evidence of photocatalytic activity because the nanoparticles melted during sintering at 1210°C. The double-fire ZnO spray-coating method successfully produced glazed materials with an active ZnO surface layer despite the high sintering temperature. The influence of experimental parameters, including the ZnO nanoparticle loading (0.03 to 1 mg/cm2) and firing temperature (650 to 800°C), were also investigated. Samples with a ZnO loading of 1 g/cm2 fired at 650°C showed the best photocatalytic activity. Increasing the temperature to 700 and 800°C led to the coalescence of ZnO nanoparticles, which reduced the photocatalytic activity.
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•Nano-ZnO morphology is changed by varying molar concentration of precursor salt.•Using a short chain length polyol different morphologies of nano-ZnO are obtained.•Nanobullets and/or ...nanorods growth at low molar concentration of precursor salt.•Bullets and nanorods show preferential growth along c axis of hexagonal structure.•Nano-spheres appear at high molar concentration of Zn(Ac)2 no preferential growth.
This paper reports the synthesis of ZnO nanostructures (nano-bullets, nanorods, nanospheres) by a facile and novel modified polyol method without surfactants, varying only the molar concentration of precursor salt (Zinc acetate dihydrate) using ethylene glycol and deionized water. At a constant temperature of 160°C, nano-bullets were obtained at a concentration of 0.6M, whereas at 0.8M nanorods were observed while at 1.0M only nanospheres appear. X-ray Diffraction, Scanning Electron Microscopy, High-Resolution Transmission Electron Microscopy and Room-Temperature Photoluminescence properties were used to characterize the nanostructures. Based on the results it is suggested a high dependence between morphology and molar concentration of the precursor salt as well as a mechanism of crystallization of the different nanostructures. The nanostructures may be used to produce optoelectronic devices.
The aim of this research was to evaluate the feasibility of using the vitrification process as an alternative solution to the disposal of a coal fly ash and metallurgical slags in landfills. The ...starting wastes were characterised in terms of chemical, granulometric, mineralogical, and microstructural analysis. A selected batch composition composed by 58.5% fly ash, 31.5% metallurgical slag and 10.0 Na
2
O% (wt%) was melted at 1450 °C and poured to obtain monolithic glass samples. The environmental behaviour of the starting wastes and the resulting glass was evaluated by standard leaching tests, which shows that vitrification leads to a stabilisation process in which the inorganic components of the wastes are immobilised throughout their incorporation into the glass structure. Moreover, vitrification transforms those hazardous wastes into a new non-hazardous glass. A preliminary study shows that the new glass is suitable for developing glass–ceramic tiles appropriate for floor pavement and wall covering.
This was a pre-post study in a network of hospitals in Mexico-City, Mexico. Participants developed and implemented Quality Improvement (QI) interventions addressing perioperative pain management.
...PAIN OUT, an international QI and research network, provided tools for web-based auditing and feedback of pain management and patient-reported outcomes (PROs) in the clinical routine. Ward- and patient-level factors were evaluated with multi-level models. Change in proportion of patients reporting worst pain ≥6/10 between project phases was the primary outcome.
Participants created locally adapted resources for teaching and pain management, available to providers in the form of a website and a special issue of a national anesthesia journal. They offered teaching to anesthesiologists, surgeons, including residents, and nurses. Information was offered to patients and families. A total of 2658 patients were audited in 9 hospitals, between July 2016 and December 2018. Participants reported that the project made them aware of the importance of: training in pain management; auditing one's own patients to learn about PROs and that QI requires collaboration between multi-disciplinary teams. Participants reported being unaware that their patients experienced severe pain and lacked information about pain treatment options. Worst pain decreased significantly between the two project phases, as did PROs related to pain interfering with movement, taking a deep breath/coughing or sleep. The opportunity of patients receiving information about their pain treatment options increased from 44% to 77%.
Patients benefited from improved care and pain-related PROs. Clinicians appreciated gaining increased expertise in perioperative pain management and methods of QI.
Abstract Background The 5-hydroxytryptamine-1A receptors are known to be involved in the inhibition of seizures in epilepsy. Objective The main aim of the present study is to determine the functional ...coupling to G-protein of the 5-HT1A receptor through 8-OH-DPAT-stimulated 35 SGTPγS binding assay in lateral temporal neocortex tissue of patients with mesial temporal lobe epilepsy (mTLE) and correlate it with clinical data. Material and methods The activation of the G protein complex was determined by 35 SGTPγS binding assay. The temporal neocortex tissue was obtained from 5 patients with mTLE during epilepsy surgery and from 5 subjects (autopsies) who died due to an accident and without history of neurological disease. Results We found that values of maximal stimulation ( Emax ) of 35 SGTPγS binding significant decreased in the mTLE group (30.8%, p < .05) when compared to the autopsy samples (65.9%). The values of potency (pEC50 ) were similar in both groups. However, we found no significant differences between the Emax and age of patient, age of seizure onset, duration of epilepsy and frequency of seizures. Also, the pEC50 values revealed no significant correlations with the clinical data. Conclusions Our data provide evidence that the lateral temporal neocortex of patients with pharmacoresistant mTLE presents alterations in the functional coupling to G-protein of the 5-HT1A receptor. Such a change could be involved in hyperexcitability in the neocortex of patients with mTLE.
The wild germplasm of S. lycopersicum var. cerasiforme has been used for the improvement of cultivated tomato. However, the use of these genetic resources depends on the detection of superior plant ...and fruit traits or resistance and tolerance to various biotic and abiotic stress conditions. In order to assess phenotypic differences by geographical origin of wild and semi-domesticated tomato, 20 accessions were collected in the states of Sinaloa, Nayarit, Jalisco, Michoacán, Puebla, Veracruz and Oaxaca, Mexico. The collection was sown and transplanted in a greenhouse under a randomized complete block design with three replications. Significant phenotypic differences were detected (P≤0.05) by germplasm origin in all the vegetative, physiological and productivity traits evaluated, except number of fruits per raceme. The most striking phenotypic difference was total fruit weight per raceme. The Oaxaca accessions were heavier (130.6 g) than those of Sinaloa, Nayarit, Jalisco and Michoacán (from 16.9 to 20 g). In fruit size, the Oaxaca accessions had values from 2.4 to 2.7 in polar and equatorial diameter, while those from other states had values from 1.3 to 1.5 cm. In this work, the smaller fruit size is an indicator of the wild origin of the material.
Familial hypercholesterolemia (FH) remains underdiagnosed and undertreated.
Report the results of the first years (2017-2019) of the Mexican FH registry.
There are 60 investigators, representing 28 ...federal states, participating in the registry. The variables included are in accordance with the European Atherosclerosis Society (EAS) FH recommendations.
To date, 709 patients have been registered, only 336 patients with complete data fields are presented. The mean age is 50 (36-62) years and the average time since diagnosis is 4 (IQR: 2-16) years. Genetic testing is recorded in 26.9%. Tendon xanthomas are present in 43.2%. The prevalence of type 2 diabetes is 11.3% and that of premature CAD is 9.8%. Index cases, male gender, hypertension and smoking were associated with premature CAD. The median lipoprotein (a) level is 30.5 (IQR 10.8-80.7) mg/dl. Statins and co-administration with ezetimibe were recorded in 88.1% and 35.7% respectively. A combined treatment target (50% reduction in LDL-C and an LDL-C <100 mg/dl) was achieved by 13.7%. Associated factors were index case (OR 3.6, 95%CI 1.69-8.73, P = .002), combination therapy (OR 2.4, 95%CI 1.23-4.90, P = .011), type 2 diabetes (OR 2.8, 95%CI 1.03-7.59, P = .036) and age (OR 1.023, 95%CI 1.01-1.05, P = .033).
The results confirm late diagnosis, a lower than expected prevalence and risk of ASCVD, a higher than expected prevalence of type 2 diabetes and undertreatment, with relatively few patients reaching goals. Recommendations include, the use of combination lipid lowering therapy, control of comorbid conditions and more frequent genetic testing in the future.
•Familial hypercholesterolemia remains underdiagnosed and undertreated in Mexico.•We present the results of the Mexican Familial Hypercholesterolemia Registry.•Over 60 investigators in 28 federal states participated in the registry.•We discuss the findings and challenges to overcome in this population.
To examine the psychometric properties of the Liebowitz Social Anxiety Scale-Self Report (LSAS-SR) based on a large sample recruited from 16 Latin American countries, Spain, and Portugal.
Two groups ...of participants were included: a non-clinical sample involving 31,243 community subjects and a clinical sample comprising 529 patients with a diagnosis of social anxiety disorder (SAD). Exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and exploratory structural equation modeling (ESEM) were used in order to determine the psychometric properties of the LSAS-SR.
EFA identified five factors with eigenvalues greater than 1.00 explaining 50.78% of the cumulative variance. CFA and ESEM supported this 5-factor structure of the LSAS-SR. The factors included: 1) speaking in public; 2) eating/drinking in front of other people; 3) assertive behaviors; 4) working/writing while being observed; and 5) interactions with strangers. Other psychometric properties such as inter-factor correlations, invariance, reliability, and validity of the scale were also found.
Psychometric data support the internal consistency and convergent validity of the LSAS-SR. It seems to be a valid and reliable measure of global social anxiety for Spanish and Portuguese-speaking countries, although when considering a multidimensional approach (factor-based assessment) it seems to be lacking some relevant social situations that are feared in those countries.
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