Evaluation of acetylcholinesterase (AChE) activity and determination of organophosphorus pesticides (OPs) are of great importance for the clinical diagnosis of several serious diseases correlated with their variations in human blood serum. In this study, a highly selective and sensitive ratiometric fluorescent probe was innovatively fabricated for the evaluation of AChE activity and the determination of OPs in tap water and food on the basis of the inner filter effect (IFE) between nitrogen-doped carbon dots (N-CDs) and 2,3-diaminophenazine (DAP). N-CDs were synthesized via a one-pot hydrothermal method by using pancreatin and 1,2-ethanediamine as precursors. N-CDs showed excellent fluorescence properties and negligible cytotoxicity on human cervical carcinoma HeLa cells and human embryonic kidney 293T cells, suggesting their further biological applications. Upon the addition of AChE and choline oxidase, acetylcholine was catalyzed to produce choline that was further oxidized to produce H₂O₂. In the presence of horseradish peroxidase, o-phenylenediamine reacted with H₂O₂ to produce fluorescent DAP. Therefore, a ratiometric fluorescent probing platform existed via IFE between N-CDs with a fluorescence signal at 450 nm and DAP with a fluorescence signal at 574 nm. OPs irreversibly impeded the catalytic activity of AChE, finally leading to the decrease of DAP amount and the variation of ratiometric fluorescent signal. Under optimal conditions, such a fluorescent probe showed relatively low detection limits of 0.38 U/L for AChE, 3.2 ppb for dichlorvos, and 13 ppb for methyl-parathion. Practical application of this ratiometric fluorescent probe to detect OPs was further verified in tap water and food samples with satisfying results that were highly consisted with the results obtained by GC–MS.

Solvent-terminated dispersive liquid-liquid microextraction (ST-DLLME) as a simple, fast, and low-cost technique was developed for simultaneous extraction of Cd²⁺ and Cu²⁺ ions in aqueous solutions. Multiobjective evolutionary algorithm based on decomposition with the aid of artificial neural networks (ANN–MOEA/D) was used for the first time in chemistry, environment, and food sciences to optimize several independent variables affecting the extraction efficiency, including disperser volume and extraction solvent volume, pH, and salt addition. To perform the ST-DLLME operations, xylene, methanol, and dithizone were utilized as an extraction solvent, disperser solvent, and chelating agent, respectively. Non-dominated sorting genetic algorithm versions II and III (NSGA II and NSGA III) as multiobjective metaheuristic algorithms and in addition central composite design (CCD) were studied as comparable optimization methods. A comparison of results from these techniques revealed that ANN-MOEA/D model was the best optimization technique owing to its highest efficiency (97.6% for Cd²⁺ and 98.3% for Cu²⁺). Under optimal conditions obtained by ANN-MOEAD, the detection limit (S/N = 3), the quantitation limit(S/N = 10), and the linear range for Cu²⁺ were 0.05, 0.15, and 0.15–1000 μg L⁻¹, respectively, and for Cd²⁺ were 0.07, 0.21, and 0.21–750 μg L⁻¹, respectively. The real sample recoveries at a spiking level of 0.05, 0.1, and 0.3 mg L⁻¹ of Cu²⁺ and Cd²⁺ ions under the optimal conditions obtained by ANN–MOEA/D ranged from 94.8 to 105%.

This study aims at investigating the impact of the irrigationmanagementfor tomato (Solanumlycopersicum 'Big Beef‘) grown under drip irrigation with mulch in an unheated polyethylene tunnel-type greenhouse.The experiment was carried out in the Chelopechene experimental field of the Institute of soil science, agrotechnologies and plant protection in town of Sofia, Bulgaria in 2018.Four different levels of irrigation have been served as treatment: T1 - full irrigation with application rate 100% of water requirements , T2 and T3 treatments – irrigationwith application rate 60% and 80% of the crop water requirements during the cluster fruit growing and cluster fruit ripening s and T4 - irrigation with 100% pan evaporation-based application rate.The total yield, yield per plant and irrigation water use efficiency (IWUE)were determined by treatments. The experimental results showed thatthe amount of water supplied for irrigation influencedfruit production of tomato grown in an unheated greenhouse.The highest tomato yield was obtained from the T1 and T4 treatments,89.205 t ha-1. и 88.11 t ha-1respectively. Reducing the irrigation application rate of 20% to 40% results in lower yield in T3 treatment by 10.5% and T2 treatment by 22% compared to the yield under full irrigation.The highest irrigation water use efficiency value of 27.03 kgm-3 was obtained for T2treatment the lowest irrigation level with. IWUE decreased in the other treatments as the amount of water applied for irrigation was larger.An economic analysis of the results was carried out.

El estudio elaborado muestra un la factibilidad económica para la creación de una planta productora de harina de lenteja de agua Lemna minor L., como complemento proteico en la alimentación de la especie tilapia roja Oreochromis spp. en el municipio de Villanueva (Casanare). Como su nombre lo indica, la actividad comercial principal será la producción de harina de lenteja de agua Lemna minor L., que será vendida como complemento proteico en la alimentación de la especie tilapia roja Oreochromis spp. en el sector piscicultor de Villanueva, considerando según el estudio de mercado, una oportunidad de negocio en la región. Fue una investigación descriptiva, pues se indagó en fuentes primarias (a través de encuestas y entrevistas) y secundarias (libros, artículos, trabajos de grado, entre otros) para luego describir cada uno de los elementos de éste para así conformar todo el estudio. Además, contó con una evaluación financiera que permitió valorar su factibilidad y confirmar si efectivamente, podía ser una oportunidad aprovechable en la región. Como resultados, se analizó lo administrativo, el mercado, sus costos y finanzas, aspectos legales y riesgos del proyecto. Desde el punto de vista financiero, es viable. Se obtuvo un período de recuperación de los recursos invertidos a partir del segundo año de funcionamiento y un VPN de 2,62%, una Tasa Interna de Retorno (TIR) 42% y Tasa Interna de Oportunidad de 4,25%. En consecuencia, el proyecto tiene el mercado, las condiciones técnicas, el personal con habilidades y conocimientos y su factibilidad económica para tener éxito. | The study shows an economic feasibility for the creation of a Lemna minor L. water duckweed plant, as a protein supplement in the feeding of the red tilapia species Oreochromis spp. in the municipality of Villanueva (Casanare). As the name implies, the main commercial activity will be the production of Lemna minor L. water duckweed flour, which will be sold as a protein supplement in the food of the red tilapia species Oreochromis spp. in the fish farming sector of Villanueva, considering according to the study of market, a business opportunity in the region. It was a descriptive investigation, since it was investigated in primary sources (through surveys and interviews) and secondary (books, articles, degree works, among others) and then described each of its elements in order to shape the entire study. In addition, it had a financial evaluation that allowed it to assess its feasibility and confirm whether it could indeed be a useful opportunity in the region. As a result, the administrative, market, costs and finances, legal aspects and project risks were analyzed. From a financial point of view, it is viable. A period of recovery of the resources invested was obtained from the second year of operation and a VPN of 2.62%, an Internal Rate of Return (IRR) 42% and Internal Rate of Opportunity of 4.25%. Consequently, the project has the market, the technical conditions, the personnel with skills and knowledge and its economic feasibility to succeed | Administrador de empresas | http://www.ustavillavicencio.edu.co/home/index.php/unidades/extension-y-proyeccion/investigacion | Pregrado

Este trabajo evalúa la eficiencia de un sistema de tratamiento en un reactor de lodos activados, operado bajo presión, ubicado en el Campus Aguas Claras, Universidad Santo Tomas sede Villavicencio. El cuál tuvo como alimentación, agua residual sintética propuesta, con el fin de controlar las características de la misma, a la entrada del reactor. Se determinó la eficiencia del reactor, inicialmente realizando una caracterización del efluente a través de monitoreo in situ de los siguientes parámetros: Temperatura del agua, pH, Oxígeno disuelto y Caudal; seguido a esto, se midieron las variables independientes de la investigación, tales como la presión entre 3, 5 y 8 psi, en relación con la ley de Henry, para determinar la solubilidad del oxígeno en la mezcla de agua, asimismo, el tiempo de retención hidráulico (3, 4 y 6 horas), posteriormente se midieron variables, ex situ, como la DBO5, DQO y los SSV, determinando de esta manera, la remoción final de la materia orgánica en el reactor (eficiencia). La temporalidad del trabajo abarcó los meses de septiembre a noviembre de 2019; en el cual a finales de septiembre se operó el biorreactor dejando un periodo de estabilización y adaptación de las bacterias de una semana. Posteriormente se iniciaron las corridas operacionales durante la primera semana de octubre, luego el muestreo y toma de datos se realizó durante las diferentes semanas del mismo mes y comienzos del mes de noviembre, periodo en el cual las variaciones para tiempo de retención hidráulico y presión se determinaron de la siguiente manera: TRH variación semanalmente, y la presión cada dos días. En este sentido, sumado a la revisión de información secundaria se evaluó y comparó el diseño actual del sistema de lodos activados operado bajo presión, respecto a referentes teóricos de reactores convencionales, consecuentemente, se identificaron aspectos a mejorar en el tratamiento, proponiendo consideraciones de diseño tendientes a mejorar la eficiencia de remoción de carga contaminante, mediante información técnica del sistema de tratamiento que facilite el proceso de mantenimiento, seguimiento y control de las condiciones operativas. Los resultados en la investigación, fueron la mayor eficiencia de remoción del 91,09% para DQO y 96,66% para DBO con una presión de 8 psi, un tiempo de retención de 4 horas y un oxígeno disuelto de 4,7 mg/L. Contrariamente, la menor eficiencia se evidenció en 53,07% con una presión de 3 psi, un tiempo de retención de 6 horas y una concentración de OD de 3,4 mg/L, así como la corrida operacional en la cual se presentó un porcentaje de remoción de 76% con una presión de 8 psi, un tiempo de retención de 6 horas y un OD 5,8 mg/L respectivamente. El análisis estadístico de varianza indico que existe una relación significativa entre la presión aplicada al biorreactor y la eficiencia que se obtuvo del proceso, indicando así que a una mayor presión se presentan mejores porcentajes de remoción, por otro lado, los tiempos de retención no presenta ninguna relación significativa con la eficiencia del proceso. | This work evaluates the efficiency of a treatment system in an activated sludge reactor, operated under pressure, located in the Santo Tomas University Aguas Claras Campus from Villavicencio -Colombia. Which was fed by synthetic waste-water proposed, in order to control the characteristics of it, at the entrance of the reactor. The efficiency of the reactor was determined, initially making a characterization of the effluent by an on-site monitoring of the following parameters: Water temperature, pH, Dissolved oxygen and Flow; after this, the independent variables of the investigation were measured, the pressure (3, 5 y 8 psi) , in relation to Henry's law, to determine the solubility of oxygen in the water mixture, the hydraulic retention time (3 , 4 y 6 hours), after which independent variables were measured. , ex situ, such as BOD5, COD and SSV, that is determining the final removal of organic matter in the reactor (efficiency). The temporality of the work covered the months of September to November; in which at the end of September the bioreactor was operated leaving a period of a week for the stabilization and adaptation of the bacteria. Later, the operational runs began during the first week of October, then the sampling and data collection was carried out during the different weeks of the same month and beginning of November, period in which the variations for hydraulic retention time and pressure were determined. as follows: TRH variation weekly, and pressure every two days. In this sense, in addition to the review of secondary information, the current design of the activated sludge system operated under pressure was evaluated and compared to theorical referents of conventional reactors, consequently, aspects to be improved in the treatment were identified, proposing design considerations tending to improve the efficiency of removal the charge, by means of technical information of the treatment system that facilitates the process of maintenance, monitoring and control of the operative conditions. The results in the investigation, are presented by the highest removal efficiency, which was 91.09% for COD and 96.66% for BOD with a pressure of 8 psi, a retention time of 4 hours and a dissolved oxygen of 4.7 mg / L, conversely, the lowest efficiency was found in 53.07% with a pressure of 3 psi, a retention time of 6 hours and an OD concentration of 3.4 mg / L, as well as the operational run in which a removal percentage of 76% was presented with a pressure of 8 psi, a retention time of 6 hours and an OD of 5.8 mg / L respectively. The statistical analysis of variance indicated that there is a significant relationship between the pressure applied to the bioreactor and the efficiency obtained from the process, indicating that at a higher pressure there are better percentages of removal, on the other hand, retention times do not present no significant relationship with the efficiency of the process. | Ingeniero Ambiental | http://www.ustavillavicencio.edu.co/home/index.php/unidades/extension-y-proyeccion/investigacion | Pregrado

In this study, a new metal-organic framework-monolith composite for in-tube solid phase microextraction phase (IT-SPME) of fluoroquinolones (FQs) was prepared. 4-Vinylbenzoic acid was copolymerized with ethylenedimethacrylate in a fused silica capillary to form porous monolith. After that, zeolitic imidazolate frameworks (ZIF-8) were synthesized in situ within the pores and the surface of the monolith by controlled layer-by-layer self-assembly of Zn2+ and imidazole. The introduction of ZIF-8 enhanced the surface area of monolith composite, and thus, improving the extraction performance of IT-SPME for FQs obviously. Under the optimized conditions, a highly sensitive method for the monitoring of FQs residue in water and honey samples was developed by the on-line combination of IT-SPME with high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The limits of detection (S/N = 3) for the targeted FQs in water and honey samples were as low as 0.14–0.61 ng/L and 0.39–1.1 ng/L, respectively. The relative standard deviations (RSDs) for intra-day and inter-day assay variability were less than 10% in all samples. The established on-line IT-SPME-HPLC-FLD was successfully used to detect ultra-trace FQs in environmental water and honey samples. Recoveries at different spiked concentrations ranged from 80.1% to 119% and 80.2–117% for water and honey samples, respectively, with satisfactory reproducibility. Compared to up-to-date reported methods, the proposed approach exhibits some features such as high sensitivity, convenience, partial automation, low consumptions of sample and solvent.

14 horizontal flow treatment wetlands for the removal of pollutants from stormwater in Shanghai Chenshan Botanical Garden in China were investigated in the second year of a long-term trial. One aimwas to compare the treatment efficiency of differently planted filter beds and unplanted ones. Despite the low nutrient concentrations, planted filters performed better than unplanted ones; e.g. for TN, the median removal efficiency for unplanted filters were 53% and 76% for planted filters. However, no correlations between dissolved oxygen and removal efficiency of oxygen depleting pollutants as well as between differently planted filters could be found. Regarding the targeted optimisation of the wetland design, for the investigated parameters COD, BOD5, NH3-N, TN and TP, the filter beds would perform almost as good if shortened by 1/3 of the length. However, it needs to be considered if further treatment goals such as reduction of pathogens should be achieved – here, the full filter passage might be necessary to achieve sufficient results. This should be subject to further research. | Au Jardin botanique de Chenshan (Shanghai), une station expérimentale composée de 14 marais filtrants à flux horizontal sous-surfacique a été analysée lors de la seconde année après sa mise en opération. L’objectif de cette étude était d’évaluer la capacité épuratoire entre des bassins plantés par 5 espèces différentes de macrophytes et des bassins non-plantés. Malgré une eau faiblement chargée, représentative des eaux pluviales de la région de Shanghai, nous avons pu observer un meilleur pourcentage d’enlèvement dans les bassins plantés comparativement à ceux non-plantés et ce, pour l’ensemble des paramètres mesurés ; par exemple pour TN, l'efficacité médiane d'élimination des filtres non plantés était de 53% et de 76% pour les filtres plantés. Toutefois, aucune corrélation de performance épuratoire n’a été observée entre l’oxygène dissous (DO) et les paramètres qui y sont associés. Pour tous les paramètres mesurés (DCO, DBO5, NH3-N, TN et TP), la taille des bassins pourrait même être optimisée en considérant une surface totale correspondant au tiers de la superficie de départ (58 m2). Par contre, si d’autres objectifs de traitement étaient envisagés, tel que la réduction de pathogènes, la surface totale devrait possiblement être considérée et fait présentement l’objet de recherche.

International audience | 14 horizontal flow treatment wetlands for the removal of pollutants from stormwater in Shanghai Chenshan Botanical Garden in China were investigated in the second year of a long-term trial. One aimwas to compare the treatment efficiency of differently planted filter beds and unplanted ones. Despite the low nutrient concentrations, planted filters performed better than unplanted ones; e.g. for TN, the median removal efficiency for unplanted filters were 53% and 76% for planted filters. However, no correlations between dissolved oxygen and removal efficiency of oxygen depleting pollutants as well as between differently planted filters could be found. Regarding the targeted optimisation of the wetland design, for the investigated parameters COD, BOD5, NH3-N, TN and TP, the filter beds would perform almost as good if shortened by 1/3 of the length. However, it needs to be considered if further treatment goals such as reduction of pathogens should be achieved – here, the full filter passage might be necessary to achieve sufficient results. This should be subject to further research. | Au Jardin botanique de Chenshan (Shanghai), une station expérimentale composée de 14 marais filtrants à flux horizontal sous-surfacique a été analysée lors de la seconde année après sa mise en opération. L’objectif de cette étude était d’évaluer la capacité épuratoire entre des bassins plantés par 5 espèces différentes de macrophytes et des bassins non-plantés. Malgré une eau faiblement chargée, représentative des eaux pluviales de la région de Shanghai, nous avons pu observer un meilleur pourcentage d’enlèvement dans les bassins plantés comparativement à ceux non-plantés et ce, pour l’ensemble des paramètres mesurés ; par exemple pour TN, l'efficacité médiane d'élimination des filtres non plantés était de 53% et de 76% pour les filtres plantés. Toutefois, aucune corrélation de performance épuratoire n’a été observée entre l’oxygène dissous (DO) et les paramètres qui y sont associés. Pour tous les paramètres mesurés (DCO, DBO5, NH3-N, TN et TP), la taille des bassins pourrait même être optimisée en considérant une surface totale correspondant au tiers de la superficie de départ (58 m2). Par contre, si d’autres objectifs de traitement étaient envisagés, tel que la réduction de pathogènes, la surface totale devrait possiblement être considérée et fait présentement l’objet de recherche.

Our objectives with this study were 1) to evaluate the effects of dietary crude protein (CP) supply on intake, digestibility, performance, N balance, and requirements of young Nellore bulls, and 2) to determine feeding behavior, water intake, and requirements of high and low residual feed intake (RFI) Nellore bulls. 42 young bulls (initial BW of 260 ± 8.1 kg; age of 7 ± 1.0 mo) were fed ad libitum and were randomly assigned to receive one of six diets with different CP concentrations for 140 d: 105 (LO), 125 (MD), or 145 g CP /kg DM (HI), and LO to HI (LH), LO to MD (LM), or MD to HI (MH) oscillating CP at a 48-h interval for each feed. The bulls were housed in a feedlot in group pens that contained electronic feeders, waterers, and a scale connected to the waterers. At the end of the experiment, bulls were slaughtered to evaluate carcass characteristics. There was no alteration in the performance of growing Nellore bulls fed with oscillating CP diets versus a static level of 125 g CP/kg DM, nor static LO and HI levels; however, there may be undesirable increases in environmental N excretion when the average dietary CP content is increased. The results suggest that dietary CP concentrations of 105, 125 g/kg DM, or within this range can be indicated for finishing young Nellore bulls, since it reaches the requirements, reduces the environmental footprint related to N excretion, and may save on costs of high-priced protein feeds. Regarding requirements, the net energy requirements for maintenance and metabolizable energy (ME) for maintenance were 77 and 122.75 Kcal/EBW0.75/d, respectively. The efficiency of ME utilization for maintenance was 62.7%. The equation obtained for net energy for gain (NEg) was: NEg (Mcal/EBW0.75/d) = 0.0535 × EBW0.75 × EBG0.7131, where EBG is the empty body gain, and the efficiency was 24.25%. Net protein for gain (NPg) was: NPg (g/d) = 227.372 × EBG – 19.479 × RE. There was a linear increase for carcass, CP, and water present in the EBW as the animal grew. The EE deposition exponentially increased as EBW increased. Low RFI bulls had lower DMI intake than high RFI bulls, and no differences were observed between the two groups regarding performance and feeding behavior measurements. The net energy requirements for maintenance, metabolizable energy for maintenance, and efficiency of metabolizable energy utilization were 63.4, 98.6 kcal/EBW0.75/d, and 64.3%, respectively for low RFI bulls, and 78.1, 123.9 kcal/EBW0.75/d, and 63.0% for high RFI bulls. We did not observe any difference regarding the composition of gain in terms of protein or fat deposition between the two groups. Both groups presented also similar carcass and non-carcass traits. Therefore, our study shows that low RFI Nellore bulls eat less, grow at a similar rate, and have lower maintenance energy requirements than high RFI bulls. We also suggest that the lower feed intake did not compromises the carcass traits of more efficient animals, which would reduce production costs and increase the competitiveness of the Brazilian beef sector on the world market. Keywords: Nellore. Nitrogen. Performance. Requirements. Residual Feed Intake. | Os objetivos deste estudo foram 1) avaliar os efeitos da suplementação dietética de proteína bruta (PB) sobre o consumo, digestibilidade, desempenho, balanço de N e exigências de machos Nelore não castrados super precoces; e 2) determinar o comportamento alimentar, o consumo de água e as exigências nutricionais de touros Nelore com alto e baixo consumo alimentar residual (CAR). 42 machos Nelore não castrados (PC inicial de 260 ± 8,1 kg; idade de 7 ± 1,0 mês) foram alimentados ad libitum e aleatoriamente distribuídos para receber uma das seis dietas com diferentes concentrações de PB por 140 d: 105 (LO), 125 (MD) ou 145 g CP / kg de MS (HI), e oscilando de LO para HI (LH), LO para MD (LM) ou MD para HI (MH) a cada 48 horas. Os animais foram alojados em um confinamento em baias em grupo que continham alimentadores eletrônicos, bebedouros e uma balança conectada aos bebedouros. Ao final do experimento os touros foram abatidos para avaliar as características da carcaça. Não foi observada alteração no desempenho de animais alimentados com dietas oscilantes de PB versus um nível estático de 125 g CP / kg MS, nem níveis estáticos LO e HI; no entanto, pode haver aumentos indesejáveis na excreção ambiental de N quando o teor médio de PB na dieta é aumentado. Os resultados sugerem que concentrações de PB na dieta de 105, 125 g / kg de MS ou dentro dessa faixa podem ser indicadas para bovinos Nelore super precoces em crescimento, pois atendem às exigências, reduzem a pegada ambiental relacionada à excreção de N e podem economizar os altos custos relacionados à alimentos proteicos. Com relação às exigências nutricionais, as exigências de energia líquida e energia metabolizável (EM) de mantença foram 77 e 122,75 Kcal/PCVZ0,75/d, respectivamente. A eficiência da utilização de EM de mantença foi de 62,7%. A equação obtida para a energia líquida para ganho (ELg) foi: ELg (Mcal/PCVZ0,75/d) = 0,0535 × PCVZ0,75 × GPCVZ0,7131, em que GPCVZ é o ganho de corpo vazio, e a eficiência foi de 24,25%. A proteína líquida para ganho (PLg) foi: PLg (g/d) = 227.372 × GPCVZ - 19.479 × ER. Foi observado um aumento linear para carcaça, PB e água presentes no PCVZ à medida que o animal crescia, já a deposição de gordura aumentou exponencialmente à medida que o PCVZ aumentou. Touros com baixo CAR apresentaram menor consumo de MS que touros com alto CAR, e não foram observadas diferenças entre os dois grupos quanto ao desempenho e comportamento alimentar. As exigências de energia líquida de mantença, energia metabolizável de mantença e eficiência da utilização de energia metabolizável foram 63,4, 98,6 kcal/PCVZ0,75/d e 64,3%, respectivamente, para touros com baixo CAR e 78,1, 123,9 kcal/PCVZ0,75/d e 63,0% para touros com alto CAR. Com relação à composição do ganho não foi observada nenhuma diferença entre os dois grupos, assim como também não foi observada nenhuma diferença com relação aos componentes carcaça e não carcaça. Nosso estudo mostra que animais baixo CAR comem menos, apresentam mesmo ganho e tem menor exigência de energia para mantença que animais alto CAR. Nós também sugerimos que o menor consumo de matéria seca não compromete negativamente características de carcaça de animais mais eficientes, o que pode resultar em redução dos custos de produção e aumento da competitividade do Brasil no mercado internacional. Palavras-chave: Consumo Alimentar Residual. Desempenho. Exigências. Nelore. Nitrogênio.