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Paints, coatings and varnishes play a crucial role in various industries and daily applications, providing essential material protection and enhancing aesthetic characteristics. However, they sometimes present environmental challenges such as corrosion, wear, and biofouling which lead to economic losses and ecological harm. Paint particles (PPs), including antifouling/anticorrosive paint particles (APPs), originate from marine, industrial, and architectural activities, primarily due to paint leakage, wear, and removal, thus significantly contributing to marine pollution. These particles are often misclassified as microplastics (MPs) because of their polymeric content, so the abundance of these materials is often underestimated. Standardized assessment methodologies are imperative to accurately differentiate and quantify them. Since PPs/APPs incorporate hazardous substances like metals, biocides, and additives that leach into the environment, further investigation into their potential impacts on organisms is of utmost importance to understand their complex composition and toxicity. While essential characterization techniques are needed, a holistic approach, focusing on sustainable paint formulations, is crucial for effective pollution mitigation. This review delves into the intricate structure of paint systems, elucidating the mechanisms governing the aging and formation of PPs/APPs, their prevalence and subsequent environmental and ecotoxicological repercussions. Additionally, it addresses challenges in sampling, processing, and characterizing PPs/APPs, advocating standardized approaches to mitigate their environmental threats, and proposing new perspectives for the future.

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In this study, we surveyed the presence of personal protective equipment (PPE) waste on the streets of Bogotá-Colombia, Lima-Perú, and Mar del Plata-Argentina. Furthermore, this work is also focused on the release capacity of Ag, Cu, and Zn metals associated with nanoparticles, and microplastics (MPs) from textile face masks (TFMs) and disposable face masks. According to our results, an association between low-income areas and PPE waste was found, which may be related to the periodicity of waste collection and economic activity. Polymers, like polypropylene, cotton-polyester, and additives, such as CaCO3, MgO, and Ag/Cu as nanoparticles, were identified. TFMs released high levels of Cu (35,900-60,200 µg·L-1), Zn (2340-2380 µg·L-1), and MPs (4528-10,640 particles/piece). Metals associated with nanoparticles leached by face masks did not present any antimicrobial activity against P. aeruginosa. Our study suggests that TFMs may leach large amounts of polluting nano/micromaterials in aquatic environments with potential toxicological effects on organisms.

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In this work, bioactive glass (BG) particles synthesized by a sol-gel method, hyaluronic acid (HYA) and collagen (COL) extracted from chicken eggshell membrane (ESM), and as-purchased polycaprolactone (PCL) were used to obtain a novel bioactive scaffold using the gel-pressing technique. Two composite mixtures in weight percent were obtained and identified as SCF-1 and SCF-2, and were characterized by using FTIR, XRD, and SEM techniques. Subsequently, the composite materials applied as coatings were evaluated in simulated body fluid solutions using electrochemical techniques. The results of bioactivity and biodegradability evaluations, carried out by immersing in simulated body fluid and phosphate-buffered saline solution, showed that the SCF-1 sample presented the best biocompatibility. In accordance with the potentiodynamic results, the 316L-SS and the SCF-1-coated SS showed a very similar corrosion potential (E corr ), around -228 mV, and current density (i corr ) values in close proximity, while the SCF-2-coated SS showed more positive E corr around -68 mV and lower i corr value in one order of magnitude. These results agree with those obtained by electrochemical impedance spectroscopy, which show a corrosion mechanism governed by activation and finite diffusion through the porous layer. In addition, results were complemented by dynamic compression testing under oscillating forces to identify the developed scaffolds' response under external forces, where the SCF-1 scaffold presented a maximum compression. The degradation resistance, bioactivity, and mechanically obtained measurements provided interesting results for potential further studies in tissue engineering.

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Neotropical birds are mostly parasitized by immature ticks and act as reservoir hosts of tick-borne pathogens of medical and veterinary interest. Hence, determining the factors that enable ticks to encounter these highly mobile hosts and increase the potential for tick dispersal throughout migratory flyways are important for understanding tick-borne disease transmission. We used 9682 individual birds from 572 species surveyed across Brazil and Bayesian models to disentangle possible avian host traits and climatic drivers of infestation probabilities, accounting for avian host phylogenetic relationships and spatiotemporal factors that may influence tick prevalence. Our models revealed that the probability of an individual bird being infested with tick larvae and nymphs was lower in partial migrant hosts and during the wet season. Notably, infestation probability increased in areas with a higher proportion of partial migrant birds. Other avian ecological traits known to influence tick prevalence (foraging habitat and body mass) and environmental condition that might constrain tick abundance (annual precipitation and minimum temperature) did not explain infestation probability. Our findings suggest that migratory flyways harbouring a greater abundance of migrant bird hosts also harbour a higher prevalence of immature ticks with potential to enhance the local transmission of tick-borne pathogens and spread across regions.

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To understand the catalytic activity of Ag-Cu cluster as catalyst of ethylene oxidation, bare Ag and Cu and Ag core/Cu12 shell and Cu core/Ag12 shell are built and optimized by density functional theory calculations incorporating the effect of the atmospheric environment. Consequently different oxygen adsorption sites on the cluster are considered: top site of the shell atoms, bridge site of the shell atoms and hollow site of the shell atoms. For each adsorption site, a few coverages are considered, both oxygen-rich condition and oxygen-poor condition. The phase diagrams of oxygen and 13-atom Ag-Cu clusters are finally determined. The pressure-temperature phase diagrams are determined for the oxygen and 13-atom Ag-Cu clusters, which reveal important insights into this system and its catalytic properties. The phase diagrams of oxygen and 13-atom Ag-Cu clusters are finally determined. The results predict the most stable phase: structure and adsorption of oxygen at certain temperature and certain pressure. Under oxygen-poor condition, the cluster structures are most likely to be changed. This information must be helpful to understand the catalytic process of Ag-Cu cluster as catalyst of ethylene oxidation.

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Introducción: La prueba de fluidez verbal semántica (FVS) es sensible para detectar deterioro cognoscitivo, es rápida y fácil de utilizar en cualquier contexto cultural, por ello se incluye en la mayoría de los protocolos de evaluación neuropsicológica. El objetivo fue estimar valores normativos de la prueba FVS (animales), en una población de adultos mayores de 65 años. Material y método: Se evaluó a 1233 sujetos sanos, cognitivamente conservados, residentes de 2 áreas (rural y urbana) de México. Se aplicó una batería de exploración neurológica y neuropsicológica, incluyendo la FVS. Resultados: El promedio de edad de la muestra fue de 73 + 6 y escolaridad de 4,0 + 3,9 años, el 59% fueron mujeres. El promedio de palabras generadas en la prueba FVS fue de 14 + 5 y se encontró una correlación de 0,16 de estas puntuaciones con edad, escolaridad y género (p < 0,001), permitiendo con ello el cálculo de los percentiles de acuerdo con estas variables. Por ello, el aporte más importante de este estudio es que el análisis de los datos permitió obtener valores normativos para una población mexicana de adultos mayores de 65 años. Además, confirmamos, al igual que otros estudios de evaluación neuropsicológica, que la prueba FVS está influida por variables sociodemográficas, como edad y escolaridad, aspectos que en el momento de construir el baremo se deben tomar en cuenta. Por último, destacamos que debido al bajo nivel educativo de nuestra población de estudio, la media de las puntuaciones obtenidas para FVS resultó inferior a otros valores normativos publicados

Introduction: The semantic verbal fluency test (SVF) is sensitive to detecting cognitive decline. It is fast and easy to use in any cultural context; therefore, it is included in most of the neuropsychological assessment protocols.Objective: To estimate normative values for the SVF test (animals), in an elderly population aged 65 years and over. Material and method: 1233 subjects who were healthy, cognitively preserved, residents of two areas (rural and urban) of Mexico were assessed. A neurological and neuropsychological exploration battery was applied, including SVF. Results: The age average was 73 + 6 and schooling was 4.0 + 3.9 years, with 59% women. The average of the words generated in the SVF test was 14 + 5, and a correlation of 0.16 of these scores with age, education, and gender was found (p<.001), this allowed the estimation of the percentiles in accordance with these variables. Conclusions: The most important contribution provided by this study was that the data analysis enabled normative values to be obtained for an elderly Mexican population aged 65 years and over. It was also confirmed, as other neuropsychological assessment studies have done, that the SVF test is influenced by socio-demographic variables, such as age and education, aspects to be considered at the time of obtaining normative values. Finally, it was noted that the average scores obtained were lower than other published reference values, due to the low educational level of our sample

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INTRODUCTION: The semantic verbal fluency test (SVF) is sensitive to detecting cognitive decline. It is fast and easy to use in any cultural context; therefore, it is included in most of the neuropsychological assessment protocols. OBJECTIVE: To estimate normative values for the SVF test (animals), in an elderly population aged 65 years and over. MATERIAL AND METHOD: 1233 subjects who were healthy, cognitively preserved, residents of two areas (rural and urban) of Mexico were assessed. A neurological and neuropsychological exploration battery was applied, including SVF. RESULTS: The age average was 73+6 and schooling was 4.0+3.9 years, with 59% women. The average of the words generated in the SVF test was 14+5, and a correlation of 0.16 of these scores with age, education, and gender was found (p<.001), this allowed the estimation of the percentiles in accordance with these variables. CONCLUSIONS: The most important contribution provided by this study was that the data analysis enabled normative values to be obtained for an elderly Mexican population aged 65 years and over. It was also confirmed, as other neuropsychological assessment studies have done, that the SVF test is influenced by socio-demographic variables, such as age and education, aspects to be considered at the time of obtaining normative values. Finally, it was noted that the average scores obtained were lower than other published reference values, due to the low educational level of our sample.

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OBJECTIVES: Sleep apnea/hypopnea syndrome is a well-recognized independent risk factor for stroke in middle-aged population, but controversy remains in older subjects. We examined the possible association between different respiratory parameters and risk of stroke in a prospective population-based cohort of 394 stroke-free elderly subjects. MATERIAL AND METHODS: Fully overnight polysomnography was performed at baseline. Over the 6 year follow-up period, 20 ischemic strokes occurred. Differences in stroke-free survival between subjects according to central apnea index (CAI) were assessed. RESULTS: We just observed association with incident ischemic stroke on central sleep apnea (CSA) episodes. Obstructive sleep apnea, time passed under 90% oxygen saturation, or arousal index were not associated. The event-free survival was lowest in the highest CAI group. This association was independent of any other vascular risk factors. CONCLUSIONS: CSA is the specific respiratory event associated with stroke in the elderly. Additionally, CSA could be a marker of silent brain ischemia, as a sign of disturbed regulation of central respiratory mechanisms, tentatively of ischemic origin.

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The aim of the present study was to assess the impact of nasal continuous positive airway pressure (nCPAP) in ischaemic stroke patients followed for 2 yrs. Stroke patients with an apnoea-hypopnoea index ≥ 20 events·h⁻¹ were randomised to early nCPAP (n = 71; 3-6 days after stroke onset) or conventional treatment (n = 69). The Barthel Index, Canadian Scale, Rankin Scale and Short Form-36 were measured at baseline, and at 1, 3, 12 and 24 months. The percentage of patients with neurological improvement 1 month after stroke was significantly higher in the nCPAP group (Rankin scale 90.9 versus 56.3% (p < 0.01); Canadian scale 88.2 versus 72.7% (p < 0.05)). The mean time until the appearance of cardiovascular events was longer in the nCPAP group (14.9 versus 7.9 months; p = 0.044), although cardiovascular event-free survival after 24 months was similar in both groups. The cardiovascular mortality rate was 0% in the nCPAP group and 4.3% in the control group (p = 0.161). Early use of nCPAP seems to accelerate neurological recovery and to delay the appearance of cardiovascular events, although an improvement in patients' survival or quality of life was not shown.

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A study was carried out with 20 goats of the Malagueña breed, half with a high (HG) and half with a low (LG) genetic capability for alpha(S1)-casein (AS1-CN) synthesis, to determine whether the 2 different genotypes (that cause differences in goat milk composition) are related to differences in nutritional feed utilization. Among the 10 HG goats, 7 had BB and 3 had AB genotypes for AS1-CN, whereas there were 7 EF and 3 FF genotypes in the 10 LG goats. The goats were fed diets differing in crude protein content (13.6 vs. 17.7% dry matter for diets 1 and 2, respectively). For each genotype group, a balance trial was conducted with each of the 2 diets in a 2-period balanced changeover designed with half the animals consuming diet 1 and the other half diet 2, determining individual feed intake and the utilization of N and energy in the diets. Greater voluntary feed intake on a metabolic body weight basis among the HG goats was identified as the first possible cause of their milk production. The HG goats also had a greater level of feed utilization, on a metabolic body weight basis, for N and energy intake. Greater ratios of N balance/ digestible N, milk protein N/digestible N, milk energy/ digestible energy, and milk energy/ME were found for HG goats compared with LG. These effects appear to be dependent on the level of protein in the diet, indicating interactive effects. The greater N and energy utilization of HG versus LG goats may explain the differences in milk composition between the 2 genotype groups.

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Haptic (touch) perception normally entails an active exploration of object surfaces over time. This is called active touch. When exploring the shape of an object, we experience both geometrical and force cues. For example, when sliding a finger across a surface with a rigid bump on it, the finger moves over the bump while being opposed by a force whose direction and magnitude are related to the slope of the bump. The steeper the bump, the stronger the resistance. Geometrical and force cues are correlated, but it has been commonly assumed that shape perception relies on object geometry alone. Here we show that regardless of surface geometry, subjects identified and located shape features on the basis of force cues or their correlates. Using paradoxical stimuli, for example combining the force cues of a bump with the geometry of a hole, we found that subjects perceived a bump. Conversely, when combining the force cues of a hole with the geometry of a bump, subjects typically perceived a hole.

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We performed a transversal-type epidemiological study in the state of Morelos, Mexico, to determine the presence of triatomines, their ecotopes, and importance in transmission of Trypanosoma cruzi Chagas. Sampling sites included domestic, peridomestic, and wild areas with collection based on the person per hour technique. We determined the entomological indices related to infestation, density, overcrowding, colonization, infection, and dispersion, which were used to calculate transmission risk. During the study, observations were made on the predominant building material, presence of cracks and illumination as factors fostering colonization. The most important results were related to infection indices, which were higher for domestic type triatomines (29%), whereas it was 4% for peridomestic sites, and 20% for sylvatic areas. The actual risk of human contact with the vector was of 0.51%, and the predominating ecotopes were stone heaps.

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Objetivo: Interpretar clínicamente los resultados de la correlación existente entre los parámetros objetivos que utilizamos en la evaluación de pacientes portadores de síntomas urinarios, en relación con la presencia de HPB. Material y métodos: se evaluó la variación de las relaciones entre el tscto rectal, la flujometría, el volumen prostático, la edad y el residuo, en 250 pacientes con síntomas urinarios. Resultados: El tamaño de la próstata aumentó con la edad, con un brusco incremento en la década de los 50 años (p<0,01), el Qmax fue menor (p<0,01) y el residuo fue más frecuente (p<0,01) cuanto más grande ( o más pesada) fue la próstata; del mismo modo se relacionó el menor flujo con la mayor prevalencia de residuo (p<0,01). mientras que la edad no demostró una influencia significativa (p>0.05) para condicionar estos resultados. Conclusión En los pacientes que consultan por trastornos miccionales en asociación con HPB clínicamente demostrable se observa una correlación estadísticamente significativa entre el mayor tamaño de la misma, un flujo bajo, menor de 10ml/s y la presencia de residuo posmicional clínicamente significativo, independientemente de la edad(AU)

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Objetivo: Interpretar clínicamente los resultados de la correlación existente entre los parámetros objetivos que utilizamos en la evaluación de pacientes portadores de síntomas urinarios, en relación con la presencia de HPB. Material y métodos: se evaluó la variación de las relaciones entre el tscto rectal, la flujometría, el volumen prostático, la edad y el residuo, en 250 pacientes con síntomas urinarios. Resultados: El tamaño de la próstata aumentó con la edad, con un brusco incremento en la década de los 50 años (p<0,01), el Qmax fue menor (p<0,01) y el residuo fue más frecuente (p<0,01) cuanto más grande ( o más pesada) fue la próstata; del mismo modo se relacionó el menor flujo con la mayor prevalencia de residuo (p<0,01). mientras que la edad no demostró una influencia significativa (p>0.05) para condicionar estos resultados. Conclusión En los pacientes que consultan por trastornos miccionales en asociación con HPB clínicamente demostrable se observa una correlación estadísticamente significativa entre el mayor tamaño de la misma, un flujo bajo, menor de 10ml/s y la presencia de residuo posmicional clínicamente significativo, independientemente de la edad

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Objetivo: Determinar el porcentaje de reestenosis posterior al tratamiento de la EUB con uretrotomía interna. Material y Métodos: Fueron tratados un total de 31 pacientes portadores de EUB cuya longitud fuera igual o menor de 0,5 cm, en los cuales el seguimiento promedio fue de 25,3 meses. Se excluyeron aquellos con áreas de espongiofibrosis, tratamiento previo por su estenosis o en tratamiento por carcinoma transicional de vejiga. En al 90 por ciento de los casos el procedimiento se realizó en forma ambulatoria bajo anestesia local. Resultados: El 58 por ciento de los pacientes presentaromn estenosis postoperatorias en un tiempo promedio de 5,4 meses. La distribución del tiempo de estenosis mostró una curva bimodal en el primer y cuarto trimestre, detectándose el 83 por ciento de las recurrencias dentro del primer año. El 100 por ciento de los pacientes que fueron tratados nuevamnete con uretrotomía interna (n:10) sufrieron reestenosis en el primer trimestre del postoperatorio. Conclusión: Aun en popblaciones altamente seleccionadas como la presente, el porcentaje de reestenosis es cvonsiderable, debiendo extenderse el seguimiento de los pacientes a largo plazo. El empleo reiterado de la uretrotomía interna en el tratamiento de la EUB res uina opción desaconsejable como tratamiento definitivo en poblaciones similares a las estudiadas. El empleo de anestesia local y manejo ambulatorio de estos pacientes debe ser considerado(AU)

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Objetivo: Determinar el porcentaje de reestenosis posterior al tratamiento de la EUB con uretrotomía interna. Material y Métodos: Fueron tratados un total de 31 pacientes portadores de EUB cuya longitud fuera igual o menor de 0,5 cm, en los cuales el seguimiento promedio fue de 25,3 meses. Se excluyeron aquellos con áreas de espongiofibrosis, tratamiento previo por su estenosis o en tratamiento por carcinoma transicional de vejiga. En al 90 por ciento de los casos el procedimiento se realizó en forma ambulatoria bajo anestesia local. Resultados: El 58 por ciento de los pacientes presentaromn estenosis postoperatorias en un tiempo promedio de 5,4 meses. La distribución del tiempo de estenosis mostró una curva bimodal en el primer y cuarto trimestre, detectándose el 83 por ciento de las recurrencias dentro del primer año. El 100 por ciento de los pacientes que fueron tratados nuevamnete con uretrotomía interna (n:10) sufrieron reestenosis en el primer trimestre del postoperatorio. Conclusión: Aun en popblaciones altamente seleccionadas como la presente, el porcentaje de reestenosis es cvonsiderable, debiendo extenderse el seguimiento de los pacientes a largo plazo. El empleo reiterado de la uretrotomía interna en el tratamiento de la EUB res uina opción desaconsejable como tratamiento definitivo en poblaciones similares a las estudiadas. El empleo de anestesia local y manejo ambulatorio de estos pacientes debe ser considerado

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The purpose of this paper is to show up the importance of the standardization concepts in American Trypanosomiasis epidemiological studies. The consistence in the measurement of some dwelling characteristics was evaluated. A validation of the Queretaro antigen for indirect hemagglutination reaction as a diagnostic test and the interobserver concordance for the serologic readings were also made. The observers were instructed in some sessions. The pretests were made in the laboratory with positive and negative sera, with sera from the studied population. Results show that the interobserver concordance after the instruction, for the dwelling variables ranged from 70% to 100%. Sensitivity of the Queretaro antigen was 100%, specificity 55%, the predictive value of a positive test 55%, and the predictive value of a negative test 93%. The interobserver concordance was 47%. The pretest and the pilot study are very important in getting the objectives of the principal study.

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BACKGROUND: Several studies have addressed arterial hypertension prevalence in Mexico. However, few include an analysis of other types of hypertension and their associated risk factors. The present work describes the prevalence of high blood pressure (HBP), isolated systolic hypertension (ISH) and diastolic hypertension (DH) and their association to certain risk factors of cardiovascular disease in an adult population of Mexico City. METHODS: A cross-sectional study was performed on 825 subjects aged between 20 and 90 years, selected by multistage cluster sampling. HBP was diagnosed by previous history if systolic blood pressure was > or = 140 mmHg and/or diastolic blood pressure > or = 90 mmHg. The measurements taken included body mass index, waist-to-hip ratio, systolic and diastolic blood pressure, levels of insulin, glucose, trigylycerides, total cholesterol, high and low density lipoprotein cholesterol, and lipoprotein(a). RESULTS: Prevalence adjusted by age for HBP was 19.4%, for ISH, 4.7%, and for DH, 4.1%. Age had an important influence on HBP and ISH with a highly significant X2t. The profile of metabolic variables was modified according to sex and type of hypertension. Thus, in DH, metabolic variables were more affected than in other types of hypertension. CONCLUSIONS: Results in HBP prevalence in the present study were lower than in other surveys performed in Mexico. It must be noted, however, that much care should be taken to choose the strategy of subject selection, since results of the prevalence of a disease depend on it to a great extent. The ISH and DH and their association to risk factors must be studied thoroughly because they constitute different clinical entities.

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