High-density polyethylene (HDPE) geomembranes are commonly used as an environmental protection liner due to their good chemical and mechanical resistances and low cost. Ultraviolet (UV) radiation is an essential issue in durability studies for pond applications. This study evaluated a 1.5-mm thick HDPE geomembrane exposed to ultraviolet fluorescent radiation for 8760 h in a laboratory and thermoanalytical and physical analyses were conducted towards the understanding of its performance after exposure. According to the results, although the geomembrane maintained the ductile behavior, it showed a 52.48% final decrease in stress crack resistance (SCR) compared to virgin SCR. Moreover, a considerable antioxidant depletion occurred after 8760 h exposure shown by the Std. OIT (standard oxidative-induction time) results, demonstrating a Std. OIT value decrease of 89.19% compared to the virgin Std. OIT. Such a behavior contributed to the susceptibility of thermal effects in the DSC (differential scanning calorimetry) curves and the losses observed in the SCR values, attesting the geomembrane’s oxidative degradation mechanism occurred and changed the polymer’s structure. Highdensity High density (HDPE cost UV (UV applications 1.5mm 15mm mm 1.5 1 5 876 results 5248 52 48 52.48 (SCR Moreover Std standard oxidativeinduction induction time 8919 89 19 89.19 differential calorimetry values s polymers polymer structure 5mm 15 1. 87 524 4 52.4 891 8 89.1 52. 89.

Groundwater is considered an important source of water aid for human consumption. However, this water can be contaminated by impurities, such contamination spots that might reach the water tables. The aim of this study was to investigate the quality of shallow groundwater in Flores neighborhood, located in the municipality of Benevides, within Belém metropolitan region, State of Pará, Brazil. Recommendations described in Standard Methods for Examination of Water and Wastewater were followed at the time to determine physical-chemical parameters such as potential hydrogen (pH), electrical conductivity (EC), total dissolved solids (TDS), apparent color, turbidity, total hardness (TH), ions and trace elements. Multivariate statistical analysis has shown that most predictive water-quality parameters set for human consumption are associated with natural events involving weathering and leaching processes. Nevertheless, parameters of nitrate, phosphate, EC, TDS and pH are also influenced by anthropic conditions in the surroundings, mainly phosphate and nitrate ions. Therefore, it can be concluded that shallow groundwaters in Flores neighborhood are unsuitable for human consumption, making it necessary for municipal public authorities to take action to solve the problem of water shortage in the borough, thus preventing the population from use those shallow groundwaters, as their consumption can bring health problems. However impurities tables Benevides region Pará Brazil physicalchemical physical chemical pH, , (pH) EC (EC) TDS, (TDS) color turbidity TH, TH (TH) elements waterquality processes Nevertheless surroundings Therefore borough problems (pH (EC (TDS (TH

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by extracellular accumulation of amyloid-β (Aβ) peptides in the brain. This study demonstrates the direct association of the disposable pipette extraction (DPX) with tandem mass spectrometry (MS/MS) for the analysis of Aβ peptides in cerebrospinal fluid (CSF) samples. Different parameters were optimized in order to improve detectability in the MS/MS including mobile phase percentage of ammonium hydroxide, mobile phase flow rate and acquisition mode. Also, this method used an electrospray ionization (ESI) low-flow probe and direct infusion of an organic solution in the MS/MS. The DPX-MS/MS method showed adequate linearity for determining Aβ peptides in CSF-linearity ranged from 0.1 to 1.5 ng mL 1. The coefficients of determination were higher than 0.99; the precision coefficient of variation (CV) ranged from 0.3 to 12.7%; and the accuracy relative standard deviation (RSD) ranged from -13.6 to 13.2%. Alzheimers Alzheimer s AD (AD amyloidβ amyloid β (Aβ brain DPX (DPX MSMS MS (MS/MS CSF (CSF samples hydroxide mode Also ESI (ESI lowflow low DPXMS/MS DPXMSMS CSFlinearity 01 0 1 0. 15 5 0.99 099 99 CV (CV 03 3 12.7% 127 12 7 RSD (RSD 13.6 136 13 6 -13. 132 2 13.2% DPXMS 0.9 09 9 12.7 13. -13 13.2 12. -1 -

This study aims to propose a new method for derivatizing fatty acids (FAs) from human milk (HM), eliminating the lipid extraction step, and simplifying the preparation for gas chromatography with a flame ionization detection (GC-FID) analysis to quantify the FAs. The Design Expert software optimized the reaction times, concentrations, and sample amount. The proposed method (PM) was validated for lyophilized HM and results for the figures of merit for precision in relative standard deviation (RSD) (RSDintra-day 1.34-4.03% and RSDinter day 2.08 5.16%), accuracy (99.87-102.16%), and robustness are within a linear range of 3 to 38% lipids in HM samples. The atmospheric solids analysis probe tandem mass spectrometry (ASAP-MS/MS) technique confirmed the efficiency of PM by expressing the molecular composition of triacylglycerol formed by FAs from the GC-FID technique. The PM requires a small sample size and conducts derivatization directly in the sample matrix, minimizing extraction errors. (FAs HM, , (HM) step GCFID GC FID (GC-FID times concentrations amount (PM RSD (RSD RSDintraday RSDintra 1.344.03% 134403 1.34 4.03% 1 34 4 03 1.34-4.03 208 2 08 2.0 5.16%, 516 5.16% 5 16 5.16%) 99.87102.16%, 998710216 99.87 102.16% 99 87 102 (99.87-102.16%) 38 samples ASAPMS/MS ASAPMSMS ASAP MS/MS MS (ASAP-MS/MS matrix errors (HM 344 1.344.03 13440 134 1.3 403 4.03 0 1.34-4.0 20 2. 51 5.16 87102 99.87102.16% 99871021 9987 99.8 10216 102.16 9 8 10 (99.87-102.16% ASAPMS MSMS 1.344.0 1344 13 1. 40 4.0 1.34-4. 5.1 8710 99.87102.16 9987102 998 99. 1021 102.1 (99.87-102.16 1.344. 4. 1.34-4 5. 871 99.87102.1 998710 102. (99.87-102.1 1.344 1.34- 99.87102. 99871 (99.87-102. 99.87102 (99.87-102 99.8710 (99.87-10 99.871 (99.87-1 (99.87- (99.87 (99.8 (99. (99 (9 (

In this work, a miniaturized version of the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method was optimized, validated, and applied for extracting eight pesticide residues in anuran liver tissue samples. The extracts were quantified by high-performance liquid chromatography with diode array detection, and the detected residues in liver tissue samples were identified by tandem mass spectrometry-liquid chromatography. The optimized extraction method entailed the scale reduction of the QuEChERS method twenty times using 500 mg of liver tissue sample, 200 mg Mg2SO4, 50 mg NaCl, 1.5 mL of acetonitrile, and a mixture of 25 mg C18 + 25 mg PSA (primary-secondary amine) as dispersive solid-phase extraction sorbent. The method was validated using liver tissue samples spiked at two levels of pesticide concentrations according to the SANTE/11312/2021 document. Recoveries ranged from 91-110% with a relative standard deviation < 20%. The method robustness assessed by the Steiner and Youden test resulted in recovery rate variations of less than 2% for all pesticides after deliberated changes in seven variables. The validated method was applied to 72 liver tissue samples from two anuran species, registering residues of some pesticides in 31 samples. The proposed method proved to be efficient, precise, and robust for determining pesticide residues in anuran liver tissues. work quick, quick (quick easy cheap effective rugged safe highperformance high performance detection spectrometryliquid spectrometry sample 20 Mg2SO4 MgSO Mg SO 5 NaCl 15 1 1. acetonitrile 2 C C1 primarysecondary primary secondary amine solidphase solid phase sorbent SANTE113122021 SANTE 11312 2021 SANTE/11312/202 document 91110% 91110 91 110% 110 91-110 20% variables 7 species 3 efficient precise tissues Mg2SO SANTE11312202 1131 202 SANTE/11312/20 9111 9 11 91-11 SANTE1131220 113 SANTE/11312/2 911 91-1 SANTE113122 SANTE/11312/ 91- SANTE11312 SANTE/11312 SANTE1131 SANTE/1131 SANTE113 SANTE/113 SANTE11 SANTE/11 SANTE1 SANTE/1 SANTE/

A green supramolecular vortex-assisted microextraction employing a mixture of 1-decanol and tetrahydrofuran (THF) was developed for the simultaneous extraction of pesticides from different classes (insecticides, fungicides, and herbicides) from water and flour samples, followed by their determination in high-performance liquid chromatography with diode array detector (HPLC-DAD). The most favorable results were achieved at pH 6.0 in the presence of 4% (m/v) NaCl, utilizing a low volume of 1-decanol and THF (75 and 400 µL, respectively), a short vortex-assisted extraction time (120 s), and centrifugation time (120 s). These conditions yielded high preconcentration factors ranging from 50.1 to 90.3 and low limits of quantification (LOQs) ranging from 1.3 to 27.3 µg L-1. The intraday (n = 10) and interday (n =1 0) precision, assessed as the percentage of relative standard deviation (RSD), varied from 4.4 to 12.4%. The optimized method was successfully applied to determine the pesticides in water and flour samples, with recoveries ranging from 81 to 111%. vortexassisted vortex assisted 1decanol decanol 1 (THF insecticides, insecticides (insecticides fungicides herbicides samples highperformance performance HPLCDAD. HPLCDAD HPLC DAD . (HPLC-DAD) 60 6 0 6. 4 m/v mv m v (m/v NaCl 75 (7 40 µL respectively, respectively , respectively) 120 (12 s, s s) s. 501 50 50. 903 90 3 90. LOQs (LOQs 13 1. 273 27 27. L1. L1 L L-1 n 10 precision RSD, RSD (RSD) 44 4. 124 12 12.4% 8 111 111% (HPLC-DAD 7 ( (1 5 9 2 L- (RSD 12.4 11 12.

Nanocomposites of GO/γ-Fe2O3 were used for magnetic dispersive solid-phase microextraction (m-d-μ-SPE) of six pesticides from river water samples, followed by the determination using high performance liquid chromatography-diode array detection. The synthesis of the nanocomposites is described and characterized using Fourier transform-infrared spectroscopy, X-ray diffraction, and scanning electron microscopy. A central composite design was used to optimize the extraction time, sample solution pH, and adsorbent amount. The solvent type and volume for desorption and the effect of the ionic strength for adsorption were also investigated. The optimum adsorption conditions were achieved at 84 min of extraction time, pH 5.4, 115 mg of absorbent, and 1% (m/v) of NaCl, while the desorption solvent selected was 1.0 mL of methanol-acetic acid (9:1, v/v). The limits of detection ranged from 0.1 to 0.9 μg L-1, and a good precision was achieved with relative standard deviation (RSD) lower than 7.6% (n = 10). The accuracy of the method was accessed by recovery tests ranging from 82 to 117% (n = 3, RSD < 8%). GO/γFe2O3 GOγFe2O3 GOγFeO GO/γ Fe2O3 GO γ Fe O GO/γ-Fe2O solidphase solid phase mdμSPE m d μ SPE (m-d-μ-SPE samples chromatographydiode chromatography diode transforminfrared transform infrared spectroscopy Xray X ray diffraction microscopy time amount investigated 8 54 5 4 5.4 11 absorbent 1 m/v mv v (m/v NaCl 10 0 1. methanolacetic methanol acetic 91, 91 9 1, (9:1 v/v. vv v/v . v/v) 01 0. 09 L1, L1 L L-1 (RSD 76 7 6 7.6 n 10. 10) 117 3 8%. 8% 8%) γFe2O3 γFe GO/γFe2O GOγFe GOγFe2O GOγ FeO Fe2O 5. (9: L- 7. γFeO γFe2O (9 (

ABSTRACT: China is the biggest muskmelon producing country across the world. Extreme application of fertilizer during planting of muskmelon poses a serious threat to the environment and food safety, so how to promote farmers to use organic fertilizer has become an important topic. This study creatively introduced green awareness into the extended framework of theory of planned behavior to explore the decisive factors of muskmelon farmers’ behavior intention to apply green organic fertilizer. The structural equation model is used for investigating behavior intention of 543 muskmelon farmers in Leting County, China. The results suggested that both subjective norm and green awareness can affect muskmelon farmers’ behavior intention positively and significantly. When the subjective norm increases by 1 standard deviation, the farmers’ intention increases by 1.028 standard deviation; for every 1 standard deviation increase in green awareness, the farmers’ intention increased by 0.703 standard deviation. ABSTRACT world safety topic 54 County significantly 1028 028 1.02 0703 0 703 0.70 5 102 02 1.0 070 70 0.7 10 1. 07 7 0.

RESUMO: A China é o maior país produtor de melão em todo o mundo. A aplicação extrema de fertilizantes durante o plantio de melão representa uma séria ameaça ao meio ambiente e à segurança alimentar, portanto, como promover os agricultores a usar fertilizante orgânico verde tornou-se um tópico importante. Este estudo introduziu criativamente a consciência verde no quadro estendido da teoria do comportamento, planejado para explorar os fatores decisivos da intenção dos agricultores de melão de aplicar fertilizante orgânico verde. O modelo de equações estruturais é usado para investigar a intenção de comportamento de 543 agricultores de melão no Condado de Leting, China. Os resultados sugerem que tanto a norma subjetiva quanto a consciência verde podem afetar positiva e significativamente o comportamento dos produtores de melão. Quando a norma subjetiva aumenta em 1, o desvio padrão, a intenção do agricultor aumenta em 1,028 desvio padrão. Para cada aumento de 1 desvio padrão na consciência verde, a intenção dos agricultores aumentou em 0,703 desvio padrão. RESUMO mundo alimentar portanto tornouse tornou se importante 54 Leting 1028 028 1,02 0703 0 703 0,70 5 102 02 1,0 070 70 0,7 10 07 7 0,

Resumen Marco contextual: La hospitalización y la intervención quirúrgica son percibidas por el niño como acontecimientos amenazantes que repercuten en su comportamiento, concretamente en la ansiedad y el miedo. Objetivo: Evaluar la eficacia de una película preparatoria para los procedimientos que deben realizarse antes de la cirugía ambulatoria con el fin de reducir la ansiedad y el miedo. Metodología: Estudio aleatorizado y controlado en el que participaron 60 niños (de 6 a 14 años) sometidos a cirugía ambulatoria. El grupo de intervención vio una película en el periodo preoperatorio y el grupo de control recibió los cuidados habituales. La eficacia de la película se midió con la escala Children’s Anxiety Meter-State y el miedo con la Children’s Fear Scale. Resultados: No hubo diferencias significativas (p > 0,05) entre el grupo de intervención que vio la película y el grupo de control que siguió los cuidados preoperatorios habituales. Conclusión: Es importante evaluar con precisión si los costes de esta intervención compensan los beneficios. Se sugiere seguir investigando en este ámbito, ajustando otros programas que resulten más eficaces en este contexto.

Abstract Background: Children often perceive hospitalization and surgery as threatening events that can lead to feelings of anxiety and fear. These feelings may affect their behaviors. Objective: To evaluate the effectiveness of an educational video in reducing anxiety and fear before outpatient surgery. Methodology: A randomized controlled study was conducted with 60 children (6 - 14 years old) undergoing outpatient surgery. The intervention group watched an educational video during the preoperative period, while the control group received standard preoperative care. The effectiveness of the video was measured using the Children’s Anxiety Meter-State scale, and fear was measured using the Children’s Fear Scale. Results: No significant differences (p > 0.05) were found between the intervention group that watched the video and the control group that received standard preoperative care. Conclusion: An accurate assessment of whether the costs of this intervention outweigh the benefits is essential. Further research is recommended, particularly in adapting other programs that have proven more effective in this context.

Resumo Enquadramento: A hospitalização e a cirurgia são consideradas pela criança como eventos ameaçadores e com repercussões no seu comportamento, nomeadamente ansiedade e medo. Objetivo: Avaliar a efetividade de um filme preparatório para procedimentos a realizar antes de uma cirurgia de ambulatório visando a redução da ansiedade e medo. Metodologia: Estudo randomizado, controlado, envolvendo 60 crianças (6-14 anos), submetidas a cirurgia de ambulatório. O grupo de intervenção visualizou um filme no período pré-operatório e o grupo de controlo recebeu os cuidados habituais. A efetividade do filme foi medida através da escala de ansiedade Children’s Anxiety Meter-State e o medo pela escala Children’s Fear Scale. Resultados: Não se observaram diferenças significativas (p > 0,05) entre o grupo de intervenção que visualizou o filme e o grupo de controlo que seguiu os cuidados pré-operatórios habituais. Conclusão: Importa avaliar de forma precisa se os custos envolvidos nesta intervenção compensam os benefícios. Sugere-se mais investigação nesta área, ajustando outros programas que se revelem mais efetivos neste contexto.

Resumen: Este artículo tiene como objetivo analizar los cambios en la dinámica residencial y comercial de un barrio del sur de Belo Horizonte. Utilizando el registro del Impuesto sobre Bienes Urbanos y Territoriales y el registro del Impuesto sobre Transmisiones Inmobiliarias, fue posible, no sólo identificar y mapear las nuevas propiedades residenciales y comerciales construidas en el barrio en la última década, sino delinear el perfil de sus nuevas residentes y consumidores. Se tiene en cuenta el concepto de gentrificación como un proceso de sustitución de una clase social de menor estatus por otra de mayor estatus, para examinar los resultados encontrados. Los datos apuntan a un proceso de cambio físico, marcado por la mayor oferta de edificios con alto nivel de acabado y alto valor, dirigidos a un grupo social de mayor estatus que los residentes anteriores. El principal actor detrás de estos cambios es el mercado inmobiliario. Resumen Horizonte Inmobiliarias posible década consumidores encontrados físico valor anteriores inmobiliario

Abstract: This article aims to analyze changes in the residential and commercial dynamics of a neighborhood in the south of Belo Horizonte. Using the Urban Property and Territorial Property Tax register and the Real Estate Transfer Tax register, it was possible, not only to identify and map the new residential and commercial properties built in the neighborhood in the last decade, but to outline the profile of its new residents and consumers. The concept of gentrification is taken into account as a process of replacing a social class with a lower status by another with a higher status, to examine the results found. The data point to a process of physical change, marked by the greater supply of buildings with a high standard of finishing and high value, aimed at a social group with a higher status than the previous residents. The main actor behind these changes is the real estate market. Abstract Horizonte possible decade consumers found change value market

Resumo: Este artigo tem como objetivo analisar as mudanças nas dinâmicas residenciais e comerciais de um bairro da Zona Sul de Belo Horizonte. Utilizando o cadastro do Imposto sobre a Propriedade Predial e Territorial Urbana e o cadastro do Imposto sobre a Transmissão de Bens Imóveis, foi possível, não apenas identificar e mapear os novos imóveis residenciais e comerciais construídos no bairro na última década, mas esboçar o perfil de seus novos moradores e consumidores. Leva-se em conta o conceito de gentrificação enquanto um processo de substituição de uma classe social com status inferior por outra com status superior, para examinar os resultados encontrados. Os dados apontam para um processo de mudança física, marcada pela maior oferta de edifícios com alto padrão de acabamento e alto valor, voltados para um grupo social com status superior ao dos antigos moradores. Tais mudanças têm como principal ator o mercado imobiliário. Resumo Horizonte Imóveis possível década consumidores Levase Leva se encontrados física valor imobiliário

Resumen: El hormigón es el material principal utilizado en la construcción en Ecuador. Para su diseño, se consideran dos características: la resistencia a la compresión y el módulo de elasticidad. El módulo de elasticidad se calcula convencionalmente en relación con la resistencia a la compresión, mediante ecuaciones establecidas en códigos de diseño. Sin embargo, investigaciones han demostrado que estas ecuaciones no reflejan con precisión la realidad en Ecuador, ya que el módulo de elasticidad no solo depende de la resistencia a la compresión, sino también de otras variables como el origen del agregado, el tipo de cemento, el proceso de producción, entre otros. En este estudio, se desarrolla un modelo que utiliza la teoría de lógica difusa para estimar el módulo de elasticidad. Se emplea un sistema de inferencia lógica ANFIS (Adaptive Neuro Fuzzy Inference Systems), utilizando datos previos de ensayos de laboratorio como conocimiento previo para crear funciones de membresía (FMs) y reglas difusas del tipo condicional (If-Then) para estimar nuevos datos del módulo de elasticidad. Además de la resistencia a la compresión, se consideran otras variables importantes en la determinación del módulo de elasticidad. Los resultados son favorables, con un coeficiente de correlación R2=0.988 y una desviación estándar S=0.097, lo que indica que el sistema de inferencia lógica (SIL) es capaz de desarrollar un modelo único que permite considerar todas las variables que influyen en la determinación del módulo de elasticidad y proporcionar valores confiables.

Abstract: Concrete is the most frequently used construction material in Ecuador. Two characteristics considered for its design are compressive strength and modulus of elasticity. The latter is conventionally calculated in relation to the former using equations established in design codes. However, research has shown that these equations do not accurately reflect the reality in Ecuador, as the modulus of elasticity depends not only on compressive strength but also on other variables such as aggregate origin, type of cement, production process, among others. In this study, a model using fuzzy logic is developed to estimate the modulus of elasticity by applying an ANFIS (Adaptive Neuro Fuzzy Inference Systems) logical inference system. Previous laboratory test data are used as prior knowledge to create membership functions (MFs) and fuzzy conditional rules (If-Then) to estimate new modulus of elasticity. In addition to compressive strength, other important variables are considered in the determination of the modulus of elasticity. The results are favorable, with a correlation coefficient R2=0.988 and a standard deviation S=0.097, indicating that the logical inference system (LIS) is capable of developing a unique model that allows considering all variables that influence the determination of the modulus of elasticity and providing reliable results.

Resumen El certificado es una evidencia de participación en un proceso y se cree que cualquier persona que posea uno tiene un requisito previo para manejar todo aquello para lo que este califica. Sin embargo, la impresión podría fallar, si el certificado se hubiera obtenido tomando atajos. (Objetivo) En este documento se desarrolló un modelo compartimental para cuantificar los factores que podrían poner en duda la autenticidad de un certificado, mediante el examen de la compensación entre el estándar académico y las tasas de reprobación, en el contexto de las instituciones de educación terciaria en Nigeria. (Metodología) El modelo se demostró válido utilizando algunos amplios teoremas matemáticos. Se derivaron los equilibrios para dicho método y el umbral para un rendimiento académico aceptable. El análisis de estabilidad se llevó a cabo empleando la teoría de la estabilidad de ecuaciones diferenciales, basada en el umbral de rendimiento académico ace ptable obtenido. (Resultados) Los resultados teóricos del modelo fueron validados por medio de simulaciones numéricas y los de las simulaciones vincularon la tasa de reprobación aceptable con el rendimiento académico que cayó por debajo del umbral del estándar establecido por las instituciones. (Conclusiones) La implicación política del resultado es que el aumento en la oferta de graduados calificados en los mercados laborales de Nigeria, así como la reducción en la tasa de desempleo, son una función del mantenimie nto de los estándares académicos.

Resumo O certificado é uma prova de participação em um processo e acredita-se que quem o possui tem como pré-requisito realizar tudo para o qual o referido certific ado o qualifica. No entanto, a impressão poderia falhar se o certificado tivesse sido obtido através de atalhos. (Objetivo) Neste artigo, foi desenvolvido um modelo compartimental para quantificar fatores que poderiam pôr em dúvida a autenticidade de um certificado, examinando o compromisso entre o padrão académico e as taxas de reprovação no contexto de instituições terciárias referenciadas na Nigéria. (Metodologia) O modelo foi provado válido usando alguns teoremas matemáticos amplos. Os equilíbrios para o modelo e o limite para desempenho acadêmico aceitável foram derivados. A análise de estabilidade foi realizada utilizando a teoria da estabilidade de equações diferenciais com base no limite de desempenho acadêmico aceitável derivado. (Resultados) Os resultados teóricos do modelo foram validados por meio de simulações numéricas e os resultados das simulações relacionaram a taxa de reprovação aceitável com o desempenho acadêmico que ficou abaixo do limite do padrão estabelecido pelas instituições. (Conclusões) A implicação política do resultado é que o aumento da oferta de licenciados qualificados nos mercados de trabalho nigerianos, bem como a redução da taxa de desemprego, é uma função da manutenção dos padrões académicos.

Abstract A certificate is evidence of participating in a process, and anyone who holds a certificate is believed to have the prerequisites necessary to handle what the certificate qualifies them for. However, this perception might be incorrect if the certificate has been obtained by taking shortcuts. (Objective) In this paper, a compartmental model was developed to quantify factors that could put the authenticity of a certificate in doubt by examining the trade-off between academic standards and failure rates in the context of tertiary education institutions in Nigeria. (Methodology) The model was validated using several mathematical theorems. Equilibria for the model and the threshold for acceptable academic performance were derived. Stability analysis was carried out by using the stability theory of differential equations based on the derived acceptable academic performance threshold. (Results) The theoretical results for the model were validated through numerical simulations, and the results from the simulations linked acceptable failure rates to academic performance falling below the threshold of the institutions’ standards. (Conclusions) The policy implication of the result is that an increase in the supply of qualified graduates into Nigeria’s labor markets, as well as a reduction in the rate of unemployment, is a function of maintaining academic standards.

Resumen Objetivo: este artículo estudia la relación entre la demanda turística y el crecimiento económico, el tipo de cambio real y la incertidumbre de política económica (EPU, por sus siglas en inglés) en Australia, China, Francia, Alemania, Italia, Japón, España, Estados Unidos y el Reino Unido. Metodología: se aplicaron pruebas de dependencia transversal, de raíz unitaria y de cointegración. El modelo de largo plazo se estimó con los siguientes métodos: PCSE, FGLS y FMOLS. Resultados: los resultados muestran una relación positiva entre el crecimiento económico y el tipo de cambio real respecto a la demanda turística. En el largo plazo, la relación de causalidad es de la incertidumbre, el tipo de cambio y el PIB al turismo. Se valida la hipótesis de retroalimentación. Limitaciones: la disponibilidad de datos. Originalidad: estudia la influencia conjunta del crecimiento económico y la EPU sobre la demanda de turismo en los países de los principales destinos mundiales de turismo internacional según los ingresos turísticos internacionales. Conclusiones: se sugiere que el turismo impulsará el crecimiento económico general, y de manera correspondiente la inversión en otros sectores de la economía también influirá en un aumento del turismo.

Abstract Objective: to study the relationship among tourism demand and economic growth, real exchange rate, and economic policy uncertainty (EPU) in Australia China, France, Germany, Italy, Japan, Spain, the United States, and the United Kingdom. Methodology: cross-section dependence, unit root, and cointegration tests were applied. The long-term model was estimated according to the Panel-Corrected Standard Error (PCSE), Feasible Generalised Least Squares (FGLS), and Fully Modified Ordinary Least Square (FMOLS). Results: the results show a positive relationship between economic growth and the real exchange rate concerning tourism demand. In the long term, the causality relationship is from uncertainty, exchange rate, and GDP to tourism. The feedback hypothesis is validated. Limitations: availability of data. Originality: it studies the joint influence of economic growth and the EPU on demand for tourism in the countries of the world’s leading destinations for international tourism according to international tourist income. Conclusions: tourism will drive general economic growth and, correspondingly, investment in other sectors of the economy will also influence an increase in tourism.

Abstract The objective of this study is to characterize the industrial solid waste generated by a geopolymeric composites precast industry in Goiás and use them in the production of mortar, in partial replacement of cement in the contents of 5%, 10%, 15% and 25%, due to its probable pozzolanic effect. For the research the residue underwent crushing in a hammer mill and sieving in a #40 mesh conducted in the industry itself. Then, physical-chemical analyzes were conducted to verify if the residue meets the parameters established by NBR 12653 (ABNT, 2014) Pozzolanic Materials - Requirements. The residue showed potential to be used as pozzolana, as in the particle size analysis only 19% was retained on sieve #325 and the moisture content also met the parameters of the aforementioned standard. However, the fire loss content and the alkali content available in ���� 2 �� were higher than the standard requirements, because the residue contains tire shavings and sodium hydroxide (NaOH) in its composition. In relation to the performance index with Portland cement at 28 days, the mortar with 5% residue in its composition met the standard conditions, but the performance with lime did not obtain the desired result, as the resistance decreased. After analysis, it has been realized that the residue does not qualify as pozzolan but can be used as a filler. 5 10 10% 15 25 25% effect 40 #4 itself Then physicalchemical physical chemical 1265 ABNT, ABNT (ABNT 2014 Requirements pozzolana 19 325 #32 However ��� � requirements NaOH (NaOH days conditions result decreased filler 1 4 # 126 201 32 #3 12 20 3

Resumo O objetivo deste estudo é caracterizar os resíduos sólidos industriais gerados por uma indústria goiana de pré-moldados de compósitos geopoliméricos e utilizá-los na produção de argamassa, em substituição parcial ao cimento nos teores de 5%, 10%, 15% e 25%, devido ao seu provável efeito pozolânico. Para a pesquisa o resíduo passou por trituração em moinho martelo e peneiramento em malha #40 realizados na própria indústria. Em seguida, foram realizadas análises físico-químicas para verificar se o resíduo atende aos parâmetros estabelecidos pela NBR 12653 (ABNT, 2014b) Materiais Pozolânicos - Requisitos. O resíduo apresentou potencial para ser utilizado como pozolana, pois na análise granulométrica apenas 19% ficaram retidos na peneira #325 e o teor de umidade também atendeu aos parâmetros da referida norma. No entanto o teor de perda ao fogo e o teor de álcalis disponíveis em Na 2 �� foram maiores do que os requisitos da norma, devido ao fato de o resíduo possuir em sua composição, raspas de pneu e hidróxido de sódio (NaOH). Em relação ao índice de desempenho com cimento Portland aos 28 dias, a argamassa que possui em sua composição 5% de resíduo atendeu as condições da norma, mas o desempenho com cal não obteve o resultado desejado, pois a resistência diminuiu. Após análise, percebeu-se que o resíduo não se enquadra como pozolana, mas pode ser usado como enchimento. prémoldados pré moldados utilizálos utilizá los 5 10 10% 15 25 25% pozolânico 40 #4 seguida físicoquímicas físico químicas 1265 ABNT, ABNT (ABNT 2014b b Requisitos pozolana 19 325 #32 norma � NaOH. NaOH . (NaOH) dias desejado diminuiu percebeuse percebeu enchimento 1 4 # 126 32 #3 (NaOH 12 3

Abstract The objective of this research was to evaluate the quality of panels produced with different proportions of Pinus oocarpa wood particles and industrial cigarette waste. The wood came from an experimental field and the cigarette waste was obtained through a donation. The particles were mixed in different proportions (100% pine particles, 90% pine particles and 10% cigarette particles, 80% pine particles and 20% cigarette particles, 70% pine particles and 30% cigarette particles). The results showed that all particleboards reached the minimum value specified by NBR 14810-2 (ABNT, 2018) for Thickness Swelling (TS). All mechanical properties evaluated showed a reduction in values with the addition of cigarette residue particles and the values obtained did not meet the minimum specified by the standard used for the modulus of rupture and modulus of elasticity. Regarding internal adhesion, the panels for T3 and T4 treatments reached the minimum value required by Brazilian standards. The thermal resistance of the panels increased with the inclusion of cigarette residue particles, but the effect was low depending on R 2 . donation 100% 100 (100 90 10 80 20 70 30 particles. particles) 148102 14810 14810- ABNT, ABNT (ABNT 2018 TS. TS (TS) elasticity adhesion T standards (10 9 1 8 7 3 1481 201 (TS (1 148 ( 14

Resumo O objetivo desta pesquisa foi avaliar a qualidade de painéis produzidos com diferentes proporções de partículas de madeira de Pinus oocarpa e resíduos de cigarro industrializado. As partículas foram misturadas em diferentes proporções (100% de partículas de pinus, 90% de partículas de pinus e 10% de partículas de cigarro, 80% de partículas de pinus e 20% de partículas de cigarro, 70% de partículas de pinus e 30% de partículas de cigarro). Os resultados evidenciaram que todos os painéis aglomerados atingiram o valor mínimo especificado pela NBR 14810-2 (ABNT, 2018) para o Inchamento em Espessura (IE). Todas as propriedades mecânicas avaliadas evidenciaram redução nos valores com a adição das partículas de resíduos de cigarro e os valores obtidos não atenderam ao mínimo especificado pela norma utilizada para o módulo de ruptura e módulo de elasticidade. Em relação a ligação interna os painéis dos tratamentos T3 e T4 atingiram o valor mínimo requerido pela norma brasileira. A resistência térmica dos painéis aumentou com a inclusão das partículas de resíduos de cigarro, porém o efeito foi baixo em função do R2. industrializado 100% 100 (100 90 10 80 20 70 30 cigarro. . cigarro) 148102 14810 2 14810- ABNT, ABNT (ABNT 2018 IE. IE (IE) elasticidade T brasileira R2 R (10 9 1 8 7 3 1481 201 (IE (1 148 ( 14