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This paper focuses on institutional influences on innovation efficiency across countries. Whereas various causes and effects of technological change have been examined, empirical investigations of the efficiency involved in innovation production are relatively few. Using data on a large sample of nations over 2018-2020 and considering corruption, regulatory quality, and state fragility as alternative institutional dimensions, our results show that greater corruption facilitates ("greases") efficiency in the production of innovations. This is also the case with improvements in regulatory quality, while greater state fragility increases inefficiency. These findings for the overall sample are somewhat different for the OECD and non-OECD subsamples, although the greasing effect of corruption remains throughout. A robustness check with patent protection and government size as alternative institutional dimensions is also conducted.
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Sludge retention time (SRT) regulation is one of the essential management techniques for refined control of the main-sidestream treatment process under the low ammonia density. It is indispensable to understand the effect of SRTs changes on the Nitrifier kinetics to obtain the functional separation of the Nitrifier and the refined control of the nitrification process. In this study, Nitrifier was cultured with conditions of 35 ± 0.5 °C, pH 7.5 ± 0.2, DO 5.0 ± 0.5 mg-O/L, and SRTs were controlled for 40 d, 20 d, 10 d, and 5 d. The net growth rate (µm), decay rate (b), specific growth rate (µ), the yield of the Nitrifier (YA), temperature parameter (TA), and inhibition coefficient (KI) have been measured and extended with the SRT decreases. Instead, the half-saturation coefficient (KS) decreased. In addition, the limited value of pH inhibition occurs (pHUL), and the pH of keeping 5% maximum reaction rate (pHLL) was in a relatively stable state. The trade of kinetics may be induced by the change of species structure of Nitrifier. The Nitrosomonas proportion was increased, and the Nitrospira was contrary with the SRT decreasing. It is a match for the functional separation of Nitrifier when SRTs was 20 d at ambient temperature under the low ammonia density. The kinetics of ammonia-oxidizing organisms (AOO) and nitrite-oxidizing organisms (NOO) in Nitrifier under different SRT conditions should be measured respectively to the refined control of the partial nitrification process in future study.
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Amoníaco , Aguas del Alcantarillado , Reactores Biológicos , Cinética , TemperaturaRESUMEN
Prediction of influent characteristics, before any treatment takes place, is of great importance to the operation and management of wastewater treatment plants (WWTPs). In this study, four machine-learning models, including multilayer perceptron (MLP), long short-term memory network (LSTM), K-nearest neighbour (KNN), and random forest (RF), are introduced to utilize real-time wastewater data from three WWTPs in North America (i.e., Tres Rios, Woodward, and one confidential plant) for predicting hourly influent characteristics. Input variables are selected using an autocorrelation analysis and a variable importance measure from RF. Both univariate and multivariate analyses are investigated to improve model accuracy. The performances of one- and multiple-step-ahead models are compared. With a short prediction horizon, all the models derived from both univariate and multivariate analyses show excellent performance. It was found that the performance deterioration as the prediction horizon expands could be mitigated significantly by including extra variables, such as meteorological variables. This work can provide valuable support for the high-temporal-resolution prediction of wastewater influent characteristics for WWTPs. The proposed models can also bridge the gap between data and decision-making in the wastewater sector.
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Aguas Residuales , Purificación del Agua , Monitoreo del Ambiente , Aprendizaje Automático , Redes Neurales de la ComputaciónRESUMEN
The sanctioning of different coronavirus vaccines (with some approved by regulators for public delivery, and others in the pipeline) has met with relief by many sections of the public and the government. However, partly due to the damages associated with the pandemic and the ensuing euphoria over vaccines' arrival, some of the challenges are mostly being ignored or are not recognized. This paper identifies some pitfalls and drawbacks in vaccine delivery. We argue that the somewhat unique tension between the speed of vaccine delivery and its scale can create opportunities for corrupt behavior that are often at odds with effective means to check abuse. While data on instances of abuse will emerge over time, it is useful to point out different avenues of abuse so that some preventive government actions can be undertaken. Specifically, we argue that the potential for out of turn delivery of vaccines and the stockpiling by unauthorized agents creates incentives for corruption, with the public or bureaucrats initiating corrupt transactions. An understanding of the potential avenues for corruption should guide the formulation of appropriate corruption-control policies and similar challenges that will be faced by policy makers in addressing future pandemics.
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The objective of this study is to explore the optimal pre-treatment procedures and statistics methods for live/dead bacterial staining using nitrite oxidizing organism (NOO) as the research aim. This staining method was developed and widely utilized to evaluate activated bacterial survival situation, because it is direct and convenience to count live and dead bacteria amount by colour distinguishes (green/red) from pictures taken by microscope. The living cell (green colour) percentage and initial bacterial chemical oxygen demand (COD) could be used for accurate reaction rate calculation at the beginning of tests. While according to the physiological principles, the detection target was limited as the organism has a complete cell shape, that was applicable for the initial phase for decay stage (live cell â particulate dead cell), but it is impossible to evaluate the decayed soluble COD from particulate dead cell during whole reaction. To model the decay stage scientifically, a two-step decay model was developed to cater to the live/dead bacterial staining analysis of biological nitrite oxidizer under inhibition condition of high nitrite concentrations at 35 °C. As results of optimal pre-treatment, a three level ultrasonic wave with 45 seconds was explored, as a reasonable observed picture number, 30 sets with 95% confident interval for datasets statistics was summarized. A set of nitrite oxidizer inhibition test (total COD and oxygen uptake rates) under high nitrite concentrations was simulated using the above model and obtained experimental schemes. Additionally, the disintegration enhancement from particulate dead cell to soluble COD by nitrite was inspected and modelled on the basis of experimental datasets.
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Nitritos , Aguas del Alcantarillado , Bacterias , Análisis de la Demanda Biológica de Oxígeno , Reactores Biológicos , Oxidación-ReducciónRESUMEN
High nitrite is a known operation parameter to inhibit the biological oxidation of nitrite to nitrate. The phenomenon is traditionally expressed using a Monod-type equation with non-competitive inhibition, in which the reaction associated with the biomass growth is reduced when high nitrite is present. On the other hand, very high nitrite is also known to slay nitrifiers. To clarify the difference between the growth inhibition and the poisoning, cell counting for living microorganisms in the nitrite oxidiser-enriched activated sludge was conducted in batch conditions under various nitrite concentrations together with measurements of biomass chemical oxygen demand (COD) concentration and oxygen uptake rate. The experiments demonstrated that these measureable parameters were all decayed when nitrite concentration exceeded 100-500 mgN/L at pH 7.0 in the system, indicating that nitrite poisoning took place. Biomass growth was recognised in lower range of nitrite which was expressed with growth inhibition only. Based on the response, a kinetic model for the biological nitrite oxidation was developed with a modification of IWA ASM1. The model was further utilised to calculate a possibility to wash out nitrite oxidiser in the aeration tank where a part of the return activated sludge was exposed to high nitrite liquor in a side-stream partial nitritation reactor.
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Reactores Biológicos/microbiología , Consorcios Microbianos/fisiología , Nitritos/metabolismo , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/instrumentación , Análisis de la Demanda Biológica de Oxígeno , Biomasa , Concentración de Iones de Hidrógeno , Consorcios Microbianos/efectos de los fármacos , Nitratos/metabolismo , Nitritos/farmacología , Oxidación-Reducción , Eliminación de Residuos Líquidos/métodosRESUMEN
Allylthiourea is a known specific inhibitor for ammonium oxidiser to suppress its oxygen uptake, and is commonly used for various kinds of batch respirometric tests to detect heterotrophic respiration in activated sludge. However, when high heterotrophs were present in the sample, it appeared the inhibitor was noticeably degraded and reached below the inhibition threshold after a couple of days, which resulted in overestimation of the heterotrophic respiration. The biological decomposition of the inhibitor was expressed with a Monod-type rate expression having a half-saturation coefficient of 980 mg-COD/L and maximum specific growth rate of 1.0 d-1. The developed kinetic model, including the growth and decay of the heterotrophs and nitrifiers, indicated that the ATU with about 90 mg-ATU/L which was initially dosed to the system would reach below the inhibition threshold of 1.0 mg-ATU/L after 10 days when 750 mg-COD/L of heterotrophs were present. From the kinetic model, an empirical formula to calculate a safe minimum ATU dose for the batch respirometric test was elaborated. The model also provided a modified experimental procedure to accurately estimate the initial heterotrophic biomass concentration in the sample and its specific decay rate based on IWA Activated Sludge Models.
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Aguas del Alcantarillado/microbiología , Tiourea/análogos & derivados , Análisis de la Demanda Biológica de Oxígeno , Biomasa , Reactores Biológicos , Procesos Heterotróficos , Cinética , Modelos Teóricos , Nitrificación , Oxígeno/análisis , Tiourea/administración & dosificación , Tiourea/química , Tiourea/metabolismo , Eliminación de Residuos Líquidos/instrumentación , Eliminación de Residuos Líquidos/métodosRESUMEN
Chalcones possess various biological properties, for example, antimicrobial, anti-inflammatory, analgesic, antimalarial, anticancer, antiprotozoal and antitubercular activity. In this study, naphthylchalcone derivatives were synthesized and characterized using 1 H NMR 13 C NMR, Fourier transform infrared and mass techniques. Yields for all derivatives were found to be >90%. Protein-drug interactions influence the absorption, distribution, metabolism and excretion (ADME) properties of a drug. Therefore, to establish whether the synthesized naphthylchalcone derivatives can be used as drugs, their binding interaction toward a serum protein (bovine serum albumin) was investigated using fluorescence, circular dichroism and molecular docking techniques under physiological conditions. Fluorescence quenching of the protein in the presence of naphthylchalcone derivatives, and other derived parameters such as association constants, number of binding sites and static quenching involving confirmed non-covalent binding interactions in the protein-ligand complex were observed. Circular dichroism clearly showed changes in the secondary structure of the protein in the presence of naphthylchalcones, indicating binding between the derivatives and the serum protein. Molecular modelling further confirmed the binding mode of naphthylchalcone derivatives in bovine serum albumin. A site-specific molecular docking study of naphthylchalcone derivatives with serum albumin showed that binding took place primarily in the aromatic low helix and then in subdomain II. The dominance of hydrophobic, hydrophilic and hydrogen bonding was clearly visible and was responsible for stabilization of the complex.
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Chalconas/química , Chalconas/metabolismo , Albúmina Sérica Bovina/química , Albúmina Sérica Bovina/metabolismo , Sitios de Unión , Chalconas/farmacocinética , Dicroismo Circular , Simulación por Computador , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Simulación del Acoplamiento Molecular , Naftoles/química , Estructura Secundaria de Proteína , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Expression of a multitude of virulence factors by multi-drug resistant microbial strains, e.g., Carbapenem Resistant Escherichia coli (Family: Enterobacteriaceae; Class: Gammaproteobacteria), is responsible for resistance against beta-lactam antibiotics. Hemolysin production and induction of hemagglutination by bacterial surface receptors inflicts direct cytotoxicity by destroying host phagocytic and epithelial cells. We have previously reported that Berberis aristata, Camellia sinensis, Cyperus rotundus Holarrhena antidysenterica and Andrographis paniculata are promising herbal leads for targeting Carbapenem resistant Escherichia coli. These herbal leads were analyzed for their anti-hemolytic potential by employing spectrophotometric assay of hemoglobin liberation. Anti-hemagglutination potential of the extracts was assessed by employing qualitative assay of visible RBC aggregate formation. Camellia sinensis (PTRC-31911-A) exhibited anti-hemolytic potential of 73.97 ± 0.03%, followed by Holarrhena antidysenterica (PTRC-8111-A) i.e., 68.32 ± 0.05%, Berberis aristata (PTRC-2111-A) i.e., 60.26 ± 0.05% and Cyperus rotundus (PTRC-31811-A) i.e., 53.76 ± 0.03%. Comprehensive, visual analysis of hemagglutination inhibition revealed that only Berberis aristata (PTRC-2111-A) and Camellia sinensis (PTRC-31911-A) exhibited anti-hemagglutination activity. However, Andrographis paniculata (PTRC-11611-A) exhibited none of the inhibitory activities. Furthermore, the pair wise correlation analysis of the tested activities with quantitative phytochemical descriptors revealed that an increased content of alkaloid; flavonoids; polyphenols, and decreased content of saponins supported both the activities. Additionally, flow cytometry revealed that cell membrane structures of CRE were damaged by extracts of Berberis aristata (PTRC-2111-A) and Camellia sinensis (PTRC-31911-A) at their respective Minimum Inhibitory Concentrations, thereby confirming noteworthy antibacterial potential of both these extracts targeting bacterial membrane; hemolysin and bacterial hemagglutination.
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Antibacterianos/farmacología , Membrana Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Extractos Vegetales/farmacología , Resistencia betalactámica , Animales , Antibacterianos/aislamiento & purificación , Carbapenémicos/farmacología , Eritrocitos/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Escherichia coli/patogenicidad , Citometría de Flujo , Hemaglutinación/efectos de los fármacos , Hemoglobinas/análisis , Hemólisis/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación , Ratas , Espectrofotometría , Virulencia/efectos de los fármacosRESUMEN
Increasing occurrence of gastroenteritis outbreaks caused by food borne opportunistic microorganisms has become a major problem in food industry as well as in immunocompromised host. Antimicrobial agents are losing their efficacy due to increase in the microbial resistance. For such reasons, conventional treatment has become limited to manage the infections state. Need of the hour is to instigate the search for safer holistic alternatives. The present study was hence conducted to assess the antibiofilm effect and mode of action of aquo alcoholic extracts of Holarrhena antidysentrica (Ha) and Andrographis paniculata (Ap) against the Salmonella enterica serovar typhimurium. Both the extracts were screened for the presence of phytocompounds followed by the characterization using Attenuated Total Reflection (ATR) infrared spectroscopy and bioactivity finger print analysis. Anti-biofilm assays were determined to test the potential of both extracts to inhibit the biofilm formation, while Propidium Iodide (PI) uptake analysis revealed that cell membrane was damaged by the exposure of nutraceuticals for 1 h. This study has demonstrated that both nutraceuticals have anti-biofilm and antimicrobial activity perturbing the membrane integrity of food-borne S. typhimurium and could be used as curative remedy to control the food borne microbial infection.
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Andrographis/química , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Holarrhena/química , Extractos Vegetales/farmacología , Salmonella typhimurium/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Biopelículas/crecimiento & desarrollo , Membrana Celular/fisiología , Permeabilidad/efectos de los fármacos , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Extractos Vegetales/aislamiento & purificación , Propidio/análisis , Salmonella typhimurium/fisiología , Análisis Espectral , Coloración y EtiquetadoRESUMEN
The multi-drug resistance offered by Carbapenem Resistant Escherichia coli (Family: Enterobacteriaceae; Class: Gammaproteobacteria) against third line antibiotics can be attributed towards its ability to develop biofilm. Such process involves adhesion and quorum-sensing induced colonization leading to biomass development. The present study explored the anti-adhesion, anti-quorum sensing and anti-biofilm potential of 05 pre-standardized potent herbals. Berberis aristata (PTRC-2111-A) exhibited maximum potential in all these activities i.e. 91.3% ± 0.05% (Anti-adhesion), 96.06% ± 0.05% (Anti-Quorum sensing) and 51.3% ± 0.07% (Anti-Biofilm formation) respectively. Camellia sinensis (PTRC-31911-A) showed both anti-adhesion (84.1% ± 0.03%) and anti-quorum sensing (90.0%) potential while Holarrhena antidysenterica (PTRC-8111-A) showed only anti-quorum sensing potential as compared to standards/antibiotics. These findings were in line with the molecular docking analysis of phytoligands against Lux S and Pilin receptors. Furthermore, the pairwise correlation analysis of the tested activities with qualitative, quantitative and bioactivity functional descriptors revealed that an increased content of alkaloid, moderate content of flavonoids and decreased content of tannins supported all the three activities. In addition, nitric oxide and superoxide scavenging activity were found to be correlated with anti-quorum sensing activity. The findings indicated clearly that B. aristata (Family: Berberidaceae) and C. sinensis (Family: Theaceae) were potent herbal leads with significant therapeutic potential which further needs to be explored at pre-clinical level in the future.
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Biopelículas/efectos de los fármacos , Productos Biológicos/farmacología , Carbapenémicos/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Extractos Vegetales/farmacología , Percepción de Quorum/efectos de los fármacos , Resistencia betalactámica , Alcaloides/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Productos Biológicos/química , Flavonoides/química , Masculino , Pruebas de Sensibilidad Microbiana , Modelos Biológicos , Modelos Moleculares , Conformación Molecular , Simulación del Acoplamiento Molecular , Fenoles/química , Extractos Vegetales/química , RatasRESUMEN
Aquo-ethanolic extract of Camellia sinensis (PTRC-31911-A), standardized using Fourier transform infrared analysis, was found to have seven common functional groups in comparison with pre-identified marker compound 'quercetin'. Phyto-chemical quantitation analysis revealed the presence of 10.65 µg/mg of flavonoids. The bioactivity fingerprint profile of PTRC-31911-A includes IC50 (Hydroxyl radical site specific scavenging) = 11.36 ± 0.5 µg/mL, IC80 (Hydroxyl radical non-site specific scavenging) = 26.44 ± 0.5 µg/mL and IC50 (Superoxide ion scavenging) = 10.141 ± 0.5 µg/mL. The drug combination analysis of PTRC-31911-A with five third-line antibiotics was carried out against carbapenem-resistant Escherichia coli. The analysis of combination of PTRC-31911-A (6.25-1000 µg/mL) and antibiotics (6.25-1000 µg/mL) revealed synergistic behaviour (fractional inhibitory concentration indices < 1) with tigecycline, ertapenem, meropenem, colistin and augmentin. The lead combination of PTRC-31911-A + ertapenem or meropenem showed maximum augmentative potential at 50 and 100 µg/mL, respectively, with nearly five-fold decrease in minimum inhibitory concentrations as compared with respective antibiotics alone. The synergistic effects implied that the antibacterial combinations of PTRC-31911-A and ertapenem, meropenem, colistin, tigecycline or augmentin would be more effective than a single monotherapy with either of the antibacterial agent.
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Camellia sinensis/química , Carbapenémicos/farmacología , Farmacorresistencia Bacteriana , Escherichia coli/efectos de los fármacos , Flavonoides/farmacología , Extractos Vegetales/farmacología , Combinación Amoxicilina-Clavulanato de Potasio/farmacología , Colistina/farmacología , Ertapenem , Depuradores de Radicales Libres/farmacología , Meropenem , Pruebas de Sensibilidad Microbiana , Minociclina/análogos & derivados , Minociclina/farmacología , Fitoquímicos/farmacología , Hojas de la Planta/química , Tienamicinas/farmacología , Tigeciclina , beta-Lactamas/farmacologíaRESUMEN
UNLABELLED: Object/Background: Vasospasm is a common cause of mortality and morbidity following rupture of intracranial aneurysm. Hemodynamic therapy instituted in these patients in the past has been replaced by direct manipulation of the spastic vessels by angioplasty and intra-arterial infusion of vasodilators. However, no case control studies exist proving its superiority. The purpose of our study was to compare the efficacy of intra-arterial nimodipine (IAN) to that of hemodynamic therapy in patients with vasospasm following aSAH. MATERIAL AND METHODS: Fifty-three patients who developed vasospasm following aSAH were included in the study. IAN was instilled in addition to hemodynamic therapy in 39 patients and 14 patients (who refused to give consent for IAN) were continued on hemodynamic therapy alone and served as controls. The response to IAN was studied on angiogram. The clinical response was assessed in both the groups at regular intervals. IAN was repeated if necessary. The outcome (GOS) at discharge and at 3 months after discharge was compared. RESULTS: Thirty-six (92.3%) out of 39 patients showed immediate angiographic reversal of vasospasm.28 of them showed clinical response, of which only 11 had lasting response. 11(28.2%) of 39 patients who received IAN had a good outcome at discharge and 23(58.9%) had a favourable outcome at 3 months follow up. In those who received hemodynamic therapy alone, 4 out of 14(28.6%) patients had a good outcome at discharge and 8 (57.1%) a favourable outcome at 3 months. CONCLUSIONS: Angiographic reversal of vasospasm is seen in majority of the patients following IAN. However, this does not necessarily translate into a long lasting clinical response. The final outcome in patients who received hemodynamic therapy is comparable to those who received additional IAN. IAN does not appear to provide a major added advantage over the conventional hemodynamic therapy.
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Aneurisma Intracraneal/tratamiento farmacológico , Nimodipina/administración & dosificación , Nimodipina/uso terapéutico , Hemorragia Subaracnoidea/tratamiento farmacológico , Vasoespasmo Intracraneal/tratamiento farmacológico , Adulto , Anciano , Femenino , Humanos , Infusiones Intraarteriales/métodos , Aneurisma Intracraneal/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Subaracnoidea/complicaciones , Resultado del Tratamiento , Vasodilatadores/uso terapéuticoRESUMEN
Activated Sludge Models (ASMs) are widely used for biological wastewater treatment plant design, optimisation and operation. In commonly used ASMs, the nitrification process is modelled as a one-step process. However, in some process configurations, it is desirable to model the concentration of nitrite nitrogen through a two-step nitrification process. In this study, the benchmark datasets published by the Water Environment Research Foundation (WERF) were used to develop a two-step nitrification model considering the kinetics of Ammonium Oxidising Bacteria (AOB) and Nitrite Oxidising Bacteria (NOB). The WERF datasets were collected from a chemostat reactor fed about 1,000 mg-NH3-N/L synthetic influent with at different sludge retention times of 20, 10 and 5-d, whereas the pH in the reactor varied in the range of 5.8 and 8.8. Supplemental laboratory batch experiments were conducted to assess the toxicity of nitrite-N on nitrifying bacteria. These tests suggested that 500 mg-N/L of nitrite at pH 7.3 was toxic to NOB and resulted in continuous decrease in bulk oxygen uptake rate. To model this phenomenon, a poisoning model was used instead of the traditional Haldane-type inhibition model. The poisoning model for NOB and AOB with different threshold poisonings for unionised NO2-N and NH3-N concentrations could successfully reproduce the three WERF datasets.
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Reactores Biológicos/microbiología , Modelos Biológicos , Bacterias/metabolismo , Concentración de Iones de Hidrógeno , Nitrificación , Compuestos de Nitrógeno/análisis , Compuestos de Nitrógeno/metabolismo , Compuestos de Nitrógeno/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidadRESUMEN
Models for predicting the fate of micropollutants (MPs) in wastewater treatment plants (WWTPs) have been developed to provide engineers and decision-makers with tools that they can use to improve their understanding of, and evaluate how to optimize, the removal of MPs and determine their impact on the receiving waters. This paper provides an overview of such models, and discusses the impact of regulation, engineering practice and research on model development. A review of the current status of MP models reveals that a single model cannot represent the wide range of MPs that are present in wastewaters today, and that it is important to start considering classes of MPs based on their chemical structure or ecotoxicological effect, rather than the individual molecules. This paper identifies potential future research areas that comprise (i) considering transformation products in MP removal analysis, (ii) addressing advancements in WWTP treatment technologies, (iii) making use of common approaches to data acquisition for model calibration and (iv) integrating ecotoxicological effects of MPs in receiving waters.
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Modelos Teóricos , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/análisis , Adsorción , Fotólisis , Volatilización , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiaciónRESUMEN
INTRODUCTION: Radioactive contamination can occur as a result of accidental or intentional release of radioactive materials (RM) into the environment. RM may deposit on clothing, skin, or hair. Decontamination of contaminated persons should be done as soon as possible to minimize the deleterious health effects of radiation. The goal of this study was to evaluate the decontamination efficiency (for residual contaminant) of the active components of "Shudhika," an indigenously developed skin decontamination kit. The study kit is for external radioactive decontamination of intact skin. METHODS: Decontamination efficiency was evaluated on the skin surface of rabbit (n = 6) and human volunteers (n = 13). 99mTc sodium pertechnetate (200-250 µCi) was used as the radio-contaminant. Skin surface area (5 × 5 cm2) of thoracic abdominal region of the rabbit and the forearm and the palm of human volunteers were used for the study. Decontamination was performed by using cotton swabs soaked with chemical decontamination agents of the kit. RESULTS: Decontamination efficiency (% of the contaminant removed) was calculated for each component of the study. Overall effectiveness of the kit was calculated to be 85% ± 5% in animal and 92% ± 3% in human skin surfaces. Running water and liquid soap with water was able to decontaminate volunteers' hand and animal skin up to 70% ± 5%. Chemical decontamination agents were applied only for trace residues (30% ± 5%). Efficiency of all the kit components was found up to be 20% ± 3% (animal) and 28% ± 2 (human), respectively. Residual contamination after final decontamination attempt for both the models was observed to be 12% ± 3% and 5% ± 2%. After 24 and 48 hours of the decontamination procedure, skin was found to be normal (no redness, erythema and edema were observed). CONCLUSION: Decontaminants of the study kit were effective in removal of localized radioactive skin contamination when water is ineffective for further decontamination. By using the chemical decontaminants of the study kit, the use of water and radioactive waste generation could be reduced. Cross-contamination could also be avoided. During radiologic emergencies where water may be radioactively contaminated, the study kit could be used.
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Descontaminación/métodos , Piel , Pertecnetato de Sodio Tc 99m , Adulto , Animales , Humanos , India , Persona de Mediana Edad , ConejosRESUMEN
Process models used for activated sludge, anaerobic digestion and in general wastewater treatment plant process design and optimization have traditionally focused on important biokinetic conversions. There is a growing realization that abiotic processes occurring in the wastewater (i.e. 'solvent') have a fundamental effect on plant performance. These processes include weak acid-base reactions (ionization), spontaneous or chemical dose-induced precipitate formation and chemical redox conversions, which influence pH, gas transfer, and directly or indirectly the biokinetic processes themselves. There is a large amount of fundamental information available (from chemical and other disciplines), which, due to its complexity and its diverse sources (originating from many different water and process environments), cannot be readily used in wastewater process design as yet. This position paper outlines the need, the methods, available knowledge and the fundamental approaches that would help to focus the effort of research groups to develop a physicochemical framework specifically in support of whole-plant process modeling. The findings are that, in general, existing models such as produced by the International Water Association for biological processes are limited by omission of key corrections such as non-ideal acid-base behavior, as well as major processes (e.g., ion precipitation). While the underlying chemistry is well understood, its applicability to wastewater applications is less well known. This justifies important further research, with both experimental and model development activities to clarify an approach to modeling of physicochemical processes.
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Modelos Biológicos , Modelos Químicos , Agua/química , Equilibrio Ácido-Base , Anaerobiosis , Reactores Biológicos , Aguas del Alcantarillado/química , Eliminación de Residuos LíquidosRESUMEN
Using recent data on the unvaccinated population across US states, this paper focuses on the determinants of vaccine hesitancy related to the COVID-19 pandemic. Findings show that more prosperous states and states with more elderly residents and more physicians have lower vaccine hesitancy. There was some evidence of the significance of race, but internet access and history of other contagious diseases failed to make a difference. States with centralized health systems and those with mask mandates generally had a lower percentage of unvaccinated populations. Finally, the presence of Democrats in state legislatures tended to lower vaccination hesitancies, ceteris paribus.
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This article studies the impact of disease epidemics on the worldwide prevalence of the shadow or the underground economy. The informal sector has low entry barriers and provides an easy short-term option for the supply of goods and services during epidemics when traditional supply lines are cut or strained. Furthermore, the enforcement resources might be directed elsewhere during epidemics, lowering the expected costs of shadow operations. Using data for over 125 nations, we find that the incidence of epidemics positively and significantly contributes to the spread of the underground sector. These findings withstand a series of robustness checks.
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The increasing use of vaccine passports (VPs) to certify immunity from the prevailing coronavirus has created positive and negative aspects that have shaken the workings of markets. The VPs are, however, not universally used and not required by all businesses and governments at this point. Given the newness associated with VPs and the ongoing uncertainty of the pandemic, full implications of VPs have not been considered. This paper provides some formal insights into the implications of the use of VPs, borrowing from the established economic theory. Recommendations for public policy are provided.