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OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on the countries of Latin America and the Caribbean. This study aims to summarise key findings from the Global Burden of Disease (GBD) 2021 in the region. We also explore disparities in burden rates and the relationship with the Socio-demographic Index (SDI). STUDY DESIGN: A cross-sectional analysis of GBD 2021 results was conducted. METHODS: We obtained the disability-adjusted life years (DALYs) due to COVID-19 for 20 countries, analysing number- and age-adjusted rates. Spearman's correlation (rho) and 95% confidence intervals (CIs) assessed the SDI-DALY rates relationship. RESULTS: COVID-19 was the leading cause disease burden in the region, with 20,437,321 DALYs in 2020 and 31,525,824 in 2021. Premature mortality (years of life lost) accounted for over 95%. Disparities existed across sexes, age groups, and countries, with Bolivia and Peru having the highest rates. A significant 2021 correlation was found (rho = -0.55, 95% CI: -0.90 to 0.19; P = 0.013) but not in 2020 (rho = -0.40, 95% CI: -0.75 to 0.05; P = 0.078). CONCLUSIONS: COVID-19 posed a significant burden in Latin America and the Caribbean, emphasising the need for targeted interventions, especially in socioeconomically disadvantaged regions.

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OBJECTIVES: To assess factors associated with the risk of severe disease in children aged 5 years or younger with laboratory-confirmed respiratory syncytial virus (RSV) infection. STUDY DESIGN: We conducted a nationwide retrospective cohort study in Mexico. METHODS: Eligible participants included children aged 5 years or younger with laboratory-confirmed RSV infection January 1, 2023, and May 15, 2024. We collected relevant clinical and epidemiological data. Risk ratios (RR) and 95% confidence intervals (CI) were employed to identify factors associated with the risk of severe disease, characterized by clinical and radiographic evidence of bronchiolitis or pneumonia requiring hospital admission. RESULTS: Data from 2022 children were analyzed and the overall risk of severe disease was 21.0% (n = 424/2022). In multiple generalized linear regression analysis, a personal history of immunosuppression (due to any cause) showed a protective effect (RR = 0.14, 95% CI 0.05-0.42, P = 0.001) against severe RSV disease, while an increased risk was documented for each additional day elapsed between the date of symptom onset and the date of seeking healthcare RR = 1.06, 95% CI 1.02-1.10, P = 0.004). CONCLUSION: These findings provide insights into risk stratification and suggest specific directions for future research. This information informs the development of targeted intervention strategies to mitigate the impact of RSV infections in this vulnerable population.

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OBJECTIVE: This study aimed to evaluate the performance of the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) case definitions for influenza-like illness (ILI) in diagnosing influenza during the 2022-2023 flu season in Mexico. STUDY DESIGN: We conducted a cross-sectional analysis of national epidemiological surveillance data in Mexico, focusing on respiratory viral pathogens. METHODS: We analyzed data from 6027 non-hospitalized patients between 5 and 65 years old who underwent molecular testing for respiratory viral pathogens. The performance of both case definitions was evaluated in terms of sensitivity, specificity, and the area under the receiver operating characteristic (AUROC) curve. RESULTS: Overall, the diagnostic accuracy of the evaluated ILI definitions in identifying influenza patients was low, particularly among older patients. When compared to the CDC, the WHO definition had a lower sensitivity but a higher specificity, resulting in a higher AUROC (P = 0.031) for the WHO criteria. CONCLUSIONS: Our findings suggest that the WHO and CDC ILI case definitions have limited accuracy for diagnosing influenza in non-hospitalized patients and highlight the need for more specific diagnostic tools to improve the detection of influenza cases during the flu season.

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OBJECTIVE: The objective of this study was to assess the survival experience of children hospitalized with laboratory-confirmed respiratory syncytial virus (RSV) infection due to bronchiolitis. STUDY DESIGN: This was a nationwide retrospective cohort study conducted in Mexico. METHODS: We analyzed data from 436 children aged 5 years and younger, with symptom onset between August 2021 and November 2022. The Kaplan-Meier method was used to compute survivor functions and their 95% confidence intervals (CI). RESULTS: High survival rates were observed, particularly within the first three weeks of hospital admission. The 3-day survival rate was 99.8% (CI 98.4-99.9%), which decreased to 98.9% (CI 96.5-99.7%), 97.5% (CI 91.9-99.3%), 86.7% (CI 48.2-97.2%), and 69.4% (CI 24.2-91.0%) on days 7, 14, 21, and 28 of hospital stay, respectively. We documented a total of 5 fatal outcomes, resulting in a mortality rate of 2.1 (95% CI 0.9-5.1) per 1,000 person-days. CONCLUSIONS: Our study analyzed a large cohort of pediatric patients with bronchiolitis caused by RSV infection, providing valuable insights into the in-hospital progression of this disease.

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OBJECTIVE: This study aimed to compare the survival experience of adult inpatients with laboratory-confirmed COVID-19 during the first three waves (wild type, Delta, and Omicron) of the pandemic in Mexico. STUDY DESIGN: A retrospective and nationwide study was conducted. METHODS: Data from 229,311 participants were analyzed using the Kaplan-Meier method, and estimates per each pandemic wave were obtained. A multivariate Cox proportional hazard regression model was fitted, and hazard ratios (HRs) and 95% confidence intervals (CIs) were computed. RESULTS: The overall mortality rate was 49.1 per 1000 person-days. Heterogeneous survival rates were observed during the analyzed emergences (log-rank test, P < 0.001), and the lowest survival functions were computed during the Omicron variant dominance. In multiple analyses and after adjusting by host characteristics and COVID-19 vaccination status, cases occurring during the Delta (vs wild type: HR = 1.03, 95% CI 1.01-1.05) and Omicron emergence were at increased risk for a fatal in-hospital outcome (HR = 1.17, 95% CI 1.13-1.22). CONCLUSIONS: Our results suggest variant-related differences in the survival rates of hospitalized patients with laboratory-positive COVID-19. When compared with the wild-type virus, lower rates were observed during the Delta and Omicron emergence.

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An important physical property in environmental samples is particle size distribution. Several processes exist to measure particle diameter, including change in electrical resistance, blocking of light, the fractionation of field flow and laser diffraction (these being the most commonly used). However, their use requires expensive and complex equipment. Therefore, a digital microscopic imaging application (DMIA) method was developed adapting the algorithms used in the helminth egg automatic detector software coupled with a neural network (NN) and Bayesian algorithms. This allowed the determination of particle size distribution in samples of waste activated sludge (WAS), recirculated sludge (RCS), and pre-treated sludge (PTS). The recirculation and electro-oxidation pre-treatment processes showed an effect in increasing the degree of solubilization, decreasing particle size and breakage factor with ranges between 44.29%, and 31.89%. Together with a final NN calibration process, it was possible to compare results. For example, the 90th percentile of equivalent diameter value obtained by the DMIA with the corresponding result for the laser diffraction method. DMIA values: 228.76 µm (WAS), 111.18 µm (RCS), and 84.45 µm (PTS). DMIA processing has advantages in terms of reducing complexity, cost and time, and offers an alternative to the laser diffraction method.

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BACKGROUND: Most of the organic content of waste activated sludge (WAS) comprises microbial cells hard to degrade, which must be pre-treated for energy recovery by anaerobic digestion (AD). Electrooxidation pre-treatment (EOP) with boron-doped diamond (BDD) electrode have been considered a promising novel technology that increase hydrolysis rate, by the disintegrating cell walls from WAS. Although electrochemical oxidation could efficiently solubilize organic substances of macromolecules, limited reports are available on EOP of WAS for improving AD. In this endeavour, the mathematical optimization study and the energy analysis of the effects of initial total solids concentrations [TS] of WAS and current density (CD) during EOP on the methane production and removal of chemical oxygen demand (COD) and volatile solids (VS) were investigated. Because limited reports are available on EOP of WAS for improving biogas production, it is not well understood; however, it has started to attract interest of scientists and engineers. RESULTS: In the present work, the energy recovery as biogas and WAS conversion were comprehensively affected by CD and [TS], in an integrated EOP and AD system. When working with WAS at 3% of [TS] pre-treated at current density of 24.1 mA/cm2, the highest COD and VS removal were achieved, making it possible to obtain the maximum methane (CH4) production of 305 N-L/kg VS and a positive energy balance of 1.67 kWh/kg VS. Therefore, the current densities used in BDD electrode are adequate to produce the strong oxidant (hydroxyl radical, ·OH) on the electrode surface, allow the oxidation of organic compounds that favours the solubilization of particulate matter and VS from WAS. CONCLUSIONS: The improvement of VS removal and COD solubilization were due to the effects of pre-treatments, which help to break down the microbial cells for faster subsequent degradation; this allows a decomposition reaction that leads to biodegrade more compounds during AD. The balance was positive, suggesting that even without any optimization the energy used as electricity could be recovered from the increased methane production. It is worth noting that this kind of analysis have not been sufficiently studied so far. It is therefore important to understand how operational parameters can influence the pre-treatment and AD performances. The current study highlights that the mathematical optimization and energy analysis can make the whole process more convenient and feasible.

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Helminths are parasitic worms that constitute a major public health problem. Conventional analytical techniques to evaluate helminth eggs in environmental samples rely on different steps, namely sedimentation, filtration, centrifugation, and flotation, to separate the eggs from a variety of particles and concentrate them in a pellet for direct observation under an optical microscope. To improve this process, a new approach was implemented in which various image processing algorithms were developed and implemented by a Helminth Egg Automatic Detector (HEAD). This allowed identification and quantification of pathogenic helminth eggs of global medical importance and it was found to be useful for relatively clean wastewater samples. After the initial version, two improvements were developed: first, a texture verification process that reduced the number of false positive results; and second, the establishment of the optimal thresholds (morphology and texture) for each helminth egg species. This second implementation, which was found to improve on the results of the former, was developed with the objective of using free software as a platform for the system. This does not require the purchase of a license, unlike the previous version that required a Mathworks® license to run. After an internal statistical verification of the system was carried out, trials in internationally recognized microbiology laboratories were performed with the aim of reinforcing software training and developing a web-based system able to receive images and perform the analysis throughout a web service. Once completed, these improvements represented a useful and cheap tool that could be used by environmental monitoring facilities and laboratories throughout the world; this tool is capable of identifying and quantifying different species of helminth eggs in otherwise difficult environmental samples: wastewater, soil, biosolids, excreta, and sludge, with a sensitivity and specificity for the TensorFlow (TF) model in the web service values of 96.82% and 97.96% respectively. Additionally, in the case of Ascaris, it may even differentiate between fertile and non-fertile eggs.

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The disinfection of helminth eggs and Escherichia coli contaminated aqueous solutions, was studied using an electro-Fenton reactor equipped with a polarized activated carbon (AC) packed bed and two chambers loaded with cation exchange resins. Experiments using different arrangements and operation conditions, revealed that effective elimination of Escherichia coli takes place in all electrochemical disinfection tests. For the more resistant helminth eggs however, adsorption, electro-oxidation and electro-Fenton experiments showed retention within the reactor and pathogen inactivation values of 0, 16, and 25%, respectively. Using helminth eggs concentration data in different sections of the reactor, optical microscopy analysis and an exploratory computer simulation, differences in the disinfection performance were explained and new recirculation and flow direction and polarization switching operation schemes were defined. The corresponding experiments revealed that the effective coupling between adsorption and electro-Fenton phenomena, all along the AC packed bed compartment, results in 100% inactivation of helminth eggs.

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OBJECTIVE: We compared anthropometric and dietary indicators between groups of older Mexican adults with accurate or inaccurate body image perception (BIP). METHODS: A cross-sectional study was carried out with 201 older adults (age ≥ 60 years) of both sexes who completed the Stunkard scale for BIP, which consists of nine silhouettes with an equivalent of body mass index (BMI) status, then, the accuracy with their real BMI was calculated and reported energy and macronutrient intake through a 24-h dietary recall directed by different geriatric centers in Colima, Mexico. Basic anthropometry and bioelectrical impedance analyses were performed. RESULTS: We found that 71.1% of the older adults had inaccurate BIP; 66.6% underestimated their body mass and 4.5% overestimated their body mass, the other 28.9% hat accurate BIP. The overall concordance between the real nutritional status and BIP was poor (kappa coefficient = 0.03). The inaccurate BIP group had a significantly higher mean body mass index, body fat percentage, muscle mass, and arm and calf circumference compared to the accurate BIP group (p < .001); only 4.3% of the older adults who were overweight and 6.2% who were obese had an accurate BIP. Regarding dietary consumption, we found significant differences only in energy and carbohydrate intake between the two groups. Finally, excess body fat was associated with an inaccurate BIP (OR: 2.8, 95% CI: 1.5-5.5). CONCLUSION: In older adults, an inaccurate BIP is generally associated with high anthropometric values and less than adequate dietary intake.

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OBJECTIVE: Establish between-day test-retest reliability metrics for 2-dimensional frontal plane projection angles (FPPAs) during the lateral step-down (LSD), single-limb squat (SLS), single-limb landing (SLL), and drop vertical jump (DVJ). DESIGN: Test-retest reliability study. SETTING: University laboratory. PARTICIPANTS: 20 healthy adults (12 female, age = 23.60 ±â€¯1.93 years old, body mass index = 24.26 ±â€¯2.54 kg/m2) were tested on 2 separate occasions 7-14 days apart. MAIN OUTCOME MEASURES: Intraclass correlation coefficients (ICC), standard errors of the measurement (SEM), and minimal detectable change (MDC) values across the LSD, SLS, SLL, and DVJ for the following body region variables: trunk, trunk on pelvis, pelvis, hip, thigh to vertical, knee, and shank to vertical. RESULTS: There was moderate-to-substantial between-day test-retest reliability for nearly all body regions across all tasks (ICC = 0.65-0.96). SEM values varied across body regions and tasks (0.9-3.5°). MDCs were variable (2.3-9.8°). Of the body regions, MDCs were largest for the knee and hip. By task, MDCs were lowest for the LSD. CONCLUSIONS: This study identified between-day test-retest reliability metrics for 2-dimensional FPPAs across a variety of body regions during commonly assessed clinical tasks. These data allow clinicians and researchers to more confidently assess true change between assessments or over time.

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Sludge generated after wastewater treatment represents an important challenge due to the large amounts produced and the need to adequately treat it. Anaerobic digestion is the preferred treatment process to obtain renewable energy as well as a biosolid with the potential to be reused in land application. This process generates biogas (methane and carbon dioxide) that may be used for energy co-generation. However, anaerobic digestion is limited by the hydrolysis step since bacteria need to break down organic matter and large molecules to allow conversion into biogas. In this study, electrochemical treatment of sludge is proposed to solubilize organic matter. Boron-doped diamond electrodes were used to treat waste activated sludge under different experimental conditions (current density, flow rate, time) to evaluate their influence on the solubilization of organic matter (in terms of chemical oxygen demand). The degree of solubilization ranged between 0.31 and 1.78%. Based on the results, optimal operating conditions were current density of 19.3 mA cm-2, flow rate of 4 L min-1, and treatment time of 30 min. Furthermore, treatment flow rate was found to play a key role in solubilization, as the process is controlled by mass transfer.

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Helminth eggs are among the most important biological contaminants in environmental engineering. They pose a significant health risk associated with poor sanitation, the use of contaminated water for irrigation, and the disposal of excreta or sludge to land. Helminths are parasitic worms transmitted to humans via their eggs, which is the infective stage of their life cycle. They are therefore relevant to public health and environmental fields due to their low infectious dose, their persistence in the environment (up to several years), and their high resistance to conventional disinfection processes. The evaluation of the efficiency of any process of inactivation, through the determination of the viability of these parasites, is fundamental, but the traditional incubation technique requires 20 days to determine both the viability and the infectivity of nematode eggs. However, the present study found that, using an inactivation process at a temperature of 60 °C for 1 hour and incubation at 28 °C and 34 °C, the absence of division of the nucleus of eggs of species from two genera, Ascaris lumbricoides and Toxocara canis, showed them to be inactivated following only 48 hours of incubation. Similar inactivation results were observed using an automatic system as long as the eggs were inactivated. The minimum time required to evaluate the inactivation of nematode eggs through the incubation technique was 48 hours.

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Anaerobic digestion of wastewater sludge is the preferred method for sludge treatment as it produces energy in the form of biogas as well as a stabilised product that may be land applied. Different pre-treatments have been proposed to solubilise organic matter and increase biogas production. Sludge electrooxidation with boron-doped diamond electrodes was used as pre-treatment for waste activated sludge (WAS) and its effect on physicochemical properties and biomethane potential (BMP) was evaluated. WAS with 2 and 3% total solids (TS) achieved 2.1 and 2.8% solubilisation, respectively, with higher solids requiring more energy. After pre-treatment, biodegradable chemical oxygen demand values were close to the maximum theoretical BMP, which makes sludge suitable for energy production. Anaerobic digestion reduced volatile solids (VS) by more than 30% in pre-treated sludge with a food to microorganism ratio of 0.15 g VSfed g-1 VSbiomass. Volatile fatty acids were lower than those for sludge without pre-treatment. Best pre-treatment conditions were 3% TS and 28.6 mA cm-2.

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A system was developed to identify and quantify up to seven species of helminth eggs (Ascaris lumbricoides -fertile and unfertile eggs-, Trichuris trichiura, Toxocara canis, Taenia saginata, Hymenolepis nana, Hymenolepis diminuta, and Schistosoma mansoni) in wastewater using different image processing tools and pattern recognition algorithms. The system was developed in three stages. Version one was used to explore the viability of the concept of identifying helminth eggs through an image processing system, while versions 2 and 3 were used to improve its efficiency. The system development was based on the analysis of different properties of helminth eggs in order to discriminate them from other objects in samples processed using the conventional United States Environmental Protection Agency (US EPA) technique to quantify helminth eggs. The system was tested, in its three stages, considering two parameters: specificity (capacity to discriminate between species of helminth eggs and other objects) and sensitivity (capacity to correctly classify and identify the different species of helminth eggs). The final version showed a specificity of 99% while the sensitivity varied between 80 and 90%, depending on the total suspended solids content of the wastewater samples. To achieve such values in samples with total suspended solids (TSS) above 150 mg/L, it is recommended to dilute the concentrated sediment just before taking the images under the microscope. The system allows the helminth eggs most commonly found in wastewater to be reliably and uniformly detected and quantified. In addition, it provides the total number of eggs as well as the individual number by species, and for Ascaris lumbricoides it differentiates whether or not the egg is fertile. The system only requires basically trained technicians to prepare the samples, as for visual identification there is no need for highly trained personnel. The time required to analyze each image is less than a minute. This system could be used in central analytical laboratories providing a remote analysis service.

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There are very few reports on the self-assembly of peptides derived from proteins of agro industrial byproducts origin. Although it has been claimed that purity is a determining factor in peptide self-assembly, whether proteins extracted using water along with other components also form self-assembled structures is not known. The results of this work prove that albumins from wheat bran, a byproduct obtained from the milling industry, can form tubular nanostructures during their hydrolysis with the V8 protease in the presence of Ca(2+). Electron microscopy of the hydrolysate revealed that under specific conditions, long filaments are formed, which are nanotubes of several microns in length, with inner and outer diameters of 100 and 200 nm, respectively. The infrared analysis of the hydrolysate identified (-)OOC-Ca(2+) interactions and changes in beta sheet content in response to variations in protein/V8/Ca(2+) molar ratios. A model that explains the probable mechanism of the observed self-assembly is discussed.

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The effects of the addition of glycerol (GLY) on the physicochemical and morphological properties of poly(vinyl alcohol) (PVA)-agar films were reported. PVA-agar films were prepared by solution cast method, and the addition of GLY in PVA-agar films altered the optical properties, resulting in a decrease in opacity values and in the color difference (ΔE) of the films. Structural characterization using Fourier transformation infrared (FTIR) spectroscopy and X-ray diffraction (XRD) indicated that the presence of GLY altered the intensity of the bands (from 1200 to 800cm(-1)) and crystallinity. The characterization of the thermal properties indicated that an increase in the agar content produces a decrease in the melting temperature and augments the heat of fusion. Similar tendencies were observed in plasticized films, but at different magnification. The formulation that demonstrated the lowest mechanical properties contained 25wt.% agar, whereas the formulation that contained 75wt.% agar demonstrated a significant improvement. The water vapor transmission rate (WVTR) and surface morphology analysis demonstrated that the structure of PVA-agar films is reorganized upon GLY addition. The physicochemical properties of PVA-agar films using GLY as a plasticizer provide information for the application of this formulation as packaging material for specific food applications.

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Individual differences in cognitive performance are partly dependent, on genetic polymporhisms. One of the single-nucleotide polymorphisms (SNP) of the CNR1 gene, which codes for cannabinoid receptor 1 (CB1R), is the rs2180619, located in a regulatory region of this gene (6q14-q15). The alleles of the rs2180619 are A > G; the G allele has been associated with addiction and high levels of anxiety (when the G allele interacts with the SS genotype of the 5-HTTLPR gene). However, GG genotype is observed also in healthy subjects. Considering G allele as risk for 'psychopathological conditions', it is possible that GG healthy subjects do not be addicted or anxious, but would have reduced performance, compared to AA subjects, in attentional control and working memory processing. One hundred and sixty-four healthy young Mexican-Mestizo subjects (100 women and 64, men; mean age: 22.86 years, SD=2.72) participated in this study, solving a task where attentional control and working memory were required. GG subjects, compared to AA subjects showed: (1) a general lower performance in the task (P = 0.02); (2) lower performance only when a high load of information was held in working memory (P = 0.02); and (3) a higher vulnerability to distractors (P = 0.03). Our results suggest that, although the performance of GG subjects was at normal levels, a lower efficiency of the endocannabinoid system, probably due to a lowered expression of CB1R, produced a reduction in the performance of these subjects when attentional control and working memory processing is challenged.

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Water supply for human consumption requires certain quality that reduces health risks to consumers. In this sense, the process of disinfection plays an important role in the elimination of pathogenic microorganisms. Even though chlorination is the most applied process based on its effectiveness and cost, its application is being questioned considering the formation of disinfection by-products (DBPs). Therefore, alternative disinfectants are being evaluated and some treatment processes have been proposed to remove DBPs precursors (organic matter. This paper reports the results of disinfection of a non conventional source of water (aquifer recharged unintentionally with raw wastewater) with peracetic acid (PAA) and ultraviolet radiation (UV) as well as nanofiltration (NF) followed by chlorination to produce safe drinking water. The results showed that a dose of 2 mg/L PAA was needed to eliminate total and faecal coliforms. For UV light, a dose of 12.40 mWs/cm2 reduced total and faecal coliforms below the detection limit. On the other hand, chlorine demand of water before NF was 1.1-1.3 mg/L with a trihalomethane formation potential (THMFP) of 118.62 microg/L, in contrast with chlorination after NF where the demand was 0.5 mg/L and THMFP of 17.64 microg/L. The recommended scheme is nanofiltration + chlorination.

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The use of biosolids for land restoration and crop production is a potential solution to improve food production worldwide. However, the microbial content usually restricts its application in crops that are consumed uncooked. An alternative practice is their use in floriculture. In this study, the effects of acid treated sludge on the development of marigold (Tagetes erecta) plants were evaluated under green house conditions. Biosolids were applied at the agronomic rate (AR) based on nitrogen requirements of the marigold. In addition, higher rates (10 and 20xAR) were applied to study their effect on the plants. Biosolids were mixed with tepetate (hard volcanic indurate layers). Due to its origin, tepetate lacks nutrients and organic matter to adequately support plant development. The best treatment for marigold development was 10xAR, as plants reached an average height of 107 cm, with a growing speed of 1.01 cm/d, which is 20 times more than the control. Plants that received no biosolids produced 0.25 buds and 0.5 flowers per plant. In contrast, AR and 10xAR showed a production that ranged from 2 to 29 buds/plant and 4 to 15 flowers/plant, respectively. These results indicate the viability of reusing acid treated biosolids to improve marigold development.

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