Advances of chromatogram retention time alignment algorithms in proteomics / 生物工程学报

Chromatography is a basic process in the current proteomics workflow, and the retention time alignment of the chromatogram is one of the important steps to effectively improve the identification and quantification accuracy. After years of development, a series of algorithms for retention time alignment have been developed. This review summarizes the advances of chromatographic retention time alignment algorithms and tools for proteomics analysis from the perspective of proteomics users, and discusses the development and future application directions.

Analysis of Specific Chromatogram of Wenjingtang Reference Sample / 中国实验方剂学杂志

Objective:To control the quality of the reference sample of Wenjingtang by establishing the specific chromatograms. Method:On the basis of analyzing 15 batches of Wenjingtang freeze-dried powder samples， a high performance liquid chromatography （HPLC） specific chromatogram analysis method of Wenjingtang was established. The system adaptability was investigated and the retention time， relative retention value and deviation caused by different chromatographic columns and instruments were calculated by using the same brand of chromatographic columns， four different brands of chromatographic columns and instruments from three different manufacturers. The precision， repeatability and stability of this method was further completed. The possible chemical components of the freeze-dried powders were speculated and identified by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UPLC-Q-TOF-MS<italic>ⁿ</italic>）. Chromatographic separation was performed on ACQUITY UPLC BEH C₁₈ column （2.1 mm×100 mm， 1.7 μm） with acetonitrile （A）-0.1% formic acid aqueous solution （B） as mobile phase for gradient elution （0-2.8 min， 10%A； 2.8-8.0 min， 10%-18%A； 8.0-12.2 min， 18%-25%A； 12.2-15.3 min， 25%-40%A； 15.3-17.4 min， 40%A； 17.4-20.5 min， 40%-90%A）， and column temperature was set at 30 ℃ with flow rate of 0.4 mL·min^-1. Mass spectrometry was performed on electrospray ionization， data were collected under positive and negative ion modes， and the detection range was <italic>m</italic>/<italic>z</italic> 50-1 600. Result:Ten characteristic peaks were selected as the distinguishing features in this specific chromatograms， and eight of them were identified by comparing with the reference standards， including paeoniflorin （peak 1）， liquiritin apioside （peak 2）， liquiritin （peak 3）， ferulic acid （peak 4）， iquiritigenin （peak 6）， cinnamaldehyde （peak 8）， paeonol （peak 9）and glycyrrhizic acid （peak 10）. By mass spectrometry analysis， 30 compounds were identified， and the source of medicinal materials were assigned. It mainly contained triterpenoid saponins and flavonoids from Glycyrrhizae Radix et Rhizoma， ginsenosides from Ginseng Radix et Rhizoma， monoterpenoid glycosides and tannins from Paeoniae Radix Alba， steroids in Achyranthis Bidentatae Radix， phenolic acids in Angelicae Sinensis Radix. Conclusion:The established characteristic chromatographic analysis method of Wenjingtang is simple， stable and repeatable. The chemical composition of the freeze-dried powder of Wenjingtang is basically defined by mass spectrometry identification and source attribution， which can provide reference for the development and quality control of Wenjingtang in the future.

Identification of Gastrodiae Rhizoma chromatographic peaks identification by liner calibration with two reference substances assisted / 药学学报

This study aimed to establish a method for positioning six chromatographic peaks occurred in HPLC profile of Gastrodiae Rhizoma. The "liner calibration with two reference substances" (LCTRS) method was used to calculate the retention time so as to assist in positioning of chromatographic peaks in terms of the prediction accuracy of retention time and the coincidence rate of chromatographic column. A total of 24 C18 chromatographic columns from different brands and types available were used to determine the retention times of six components in Gastrodiae Rhizoma, then the average retention time of each component was obtained as standard retention time (SRT). Parishin E (peak 3) and Parishin A (peak 6) were simultaneously taken as reference substance to forecast the retention time of the other four components by using the LCTRS method. Four different C18 columns were employed to verify the method. Meanwhile, for the purpose of comparison, the relative retention time (RRT) method was applied to forecast the retention time, by using Parishin E as the single reference substance. The comparison between LCTRS and RRT methods indicated that the former was more accurate in predicting the retention time and more applicable in utilization of chromatographic columns. This study demonstrated that the LCTRS method shows the superior performance in positioning of chromatographic peak, and therefore has a good prospect of application.

Peptide retention prediction algorithm and its application in proteomics / 中国药科大学学报

@#Most of the proteomics analysis methods based on tandem mass spectrometry rely on the matching scoring of actual spectrum and theoretical spectrum, the interference of a large number of co-eluting peptides could cause error in the identification and quantification of peptides and proteins. Peptide retention time prediction, as a auxiliary and verification index of the peptide, can transition the chromatographic behavior into stable independent time attributes, and improve the accuracy of the peptide identification. Prediction of peptide chromatographic retention in complex systems is also of great significance for optimizing proteomics determination conditions and improving the detection rate and repeatability of mass spectrometry data in data-independent acquisition. This review focused on the chromatographic retention prediction method of unmodified peptides and modified peptides, summarizes the content, characteristics and limitations of four types of peptide retention time prediction methods based on standardized indexes, peptide molecular models, amino acid residue parameters, and machine learning, as well as their applications in proteomics, with a prospect of their future.

Safety analysis of delayed use of nasointestinal tube / 中国医师杂志

Objective:To investigate the indwelling time of nasointestinal tube and the safety of delayed use, and to analyze the main influencing factors.Methods:216 patients with indwelling nasointestinal tube were analyzed retrospectively by designing a survey from 2018 to 2020. Receiver operating characteristic curve (ROC) analysis method was used to analyze the threshold of pipe blocking time.Results:Among the 216 patients, the shortest indwelling time was 7 days and the longest was 120 days. The incidence rate of tube blockage, aspiration and accidental extubation was 6.02%(13/216), 2.78%(6/216) and 1.39%(3/216), respectively. Statistical analysis of 13 patients with tube occlusion showed that the incidence of tube occlusion was related to the indwelling time and the speed of pumping (χ 2=46.056, 36.564, P<0.05). In addition, the duration of nasointestinal tube use not only affected the incidence of tube occlusion, but also was related to the incidence of aspiration. With the prolongation of catheter insertion time, the rate of tube occlusion and the incidence of aspiration also increased significantly (χ 2=13.190, P<0.05). ROC curve was used to analyze the correlation between the indwelling time of the feeding tube and the occlusion. The area under the ROC curve was 0.933 (95% CI: 0.886-0.981, P<0.001), the Youden index was 0.829, and the cut-off value of the best indwelling time was 52.5 d. The sensitivity and specificity of the method for determining the occurrence of pipe blockage were 92.3% and 90.6%. Conclusions:It is safe and feasible to extend the indwelling time of nasointestinal tube appropriately, which can reduce the discomfort caused by frequent replacement of nasointestinal tube in patients with long-term enteral nutrition, and reduce the medical cost at the same time. However, when the indwelling time exceeds the threshold, the probability of tube blockage increases significantly, so we should maintain the catheter or replace it in time.

Modelación dinámica del comportamiento hidrológico de un humedal urbano bajo condiciones del fenómeno ENSO / Dynamic modeling of the hydrological behavior of an urban wetland under conditions of ENSO phenomenon

RESUMEN El estado actual y las continuas alteraciones que aquejan a los humedales ubicados en la ciudad de Bogotá (Colombia), motiva el desarrollo de instrumentos y herramientas, que permitan explicar su comportamiento hidrológico bajo tensiones climáticas, como lo es el fenómeno ENSO. Este artículo presenta la formulación de un modelo de las condiciones hidrológicas del humedal urbano de Torca. La simulación, se realizó con el software Vensim® y la validación estadística del modelo, se efectuó mediante un análisis de sensibilidad multivariable (MVSS), a partir del método Montecarlo. Se evidenció que en los años de ocurrencia del fenómeno climatológico ENSO (2001) y (2011), el patrón de comportamiento de la precipitación y del flujo de entrada (Qi) de la cuenca aferente del humedal fueron paralelos. El tiempo hidráulico de retención (THR) sugirió un comportamiento inverso con relación a la precipitación. En efecto, la precipitación promedio mensual fue de 47,8mm y 158,7mm y el THR promedio fue de 55 días y 33 días, para los años El Niño y La Niña, respectivamente. El flujo de entrada y de salida presentaron un comportamiento paralelo durante el período de estudio, debido, probablemente, a que el cuerpo de agua se convirtió en un cauce de salida. Durante El Niño, cuatro meses registraron desbordamiento del humedal (junio, septiembre, octubre y diciembre), con volúmenes de agua superiores a 130.645m3. Durante La Niña, todos los meses registraron desbordamiento del humedal, a excepción de agosto y septiembre, en donde se observaron volúmenes de agua de 100.018m3 y 109.166m3, respectivamente.

ABSTRACT The current state and the continuous changes that affect the wetlands located in the city of Bogotá (Colombia), motivates the development of instruments and tools that illustrate their hydrological behavior under climatic stresses such as the ENSO phenomenon. This article presents the formulation of a model of the hydrological conditions of the urban wetland of Torca. The simulation was carried out with the Vensim® software and the statistical validation of the model was carried out by means of a multivariate sensitivity analysis (MVSS) using the Montecarlo method. It was evidenced that in the years of occurrence of the ENSO climatological phenomenon (2001) and (2011), the behavior pattern of precipitation and inflow (Qi) of the afferent basin of the wetland were parallel. Hydraulic retention time (THR) suggested an inverse behavior in relation to precipitation. Indeed, the average monthly rainfall was 47,8mm and 158,7mm, and the average THR was 55 days and 33 days for the El Niño and La Niña years, respectively. The inflow and outflow presented a parallel behavior during the study period, probably due to the fact that the body of water became an outlet channel. During El Niño, the wetland overflowed for four months (June, September, October and December), with volumes exceeding 130,645m3. During La Niña, the wetland overflowed every month; except for August and September, where volumes of 100.018m3 and 109.166m3 were observed, respectively.

Retention Time and Ion Abundance Ratio of 8 Common Drugs (Poisons) by LC-MS/MS Qualitative Analysis / 法医学杂志

Objective To investigate the maximum allowable deviations of retention time and ion abundance ratio of the 8 common drugs (poisons) from 3 categories, poisons (methamphetamine, morphine, ketamine), benzodiazepines (estazolam, midazolam, diazepam, clonazepam) and barbiturates (phenobar-bital) in blood, by liquid chromatograpy-tandem mass spectrometry (LC-MS/MS) in forensic toxicology analysis. Methods The deviations of retention time and ion abundance ratio at 7 low mass concentrations, limit of detection (LOD), 2LOD, limit of quantitation (LOQ), 1.5LOQ, 2LOQ, 4LOQ and 6LOQ, were tested by LC-MS/MS after liquid-liquid extraction under the conditions of two chromatographic columns and three chromatographs. Results The deviation of absolute retention time of 98.11% of 8 drugs (poisons) in the blood samples was within the range of ± 0.05 min, and that of the relative retention time of 96.21% was within the range of±0.4%. The maximum deviation of the ion abundance ratio was highly correlated with the mass concentration. When the mass concentration of drugs (poisons) was LOQ or above, more than 95% of the absolute deviation and relative deviation of the ion abundance ratio were in the range of±25% and±40%, respectively; when the mass concentration was below LOQ, the range could be expanded to±35% and±50%, respectively. Conclusion It is recommended for the determination range of the absolute retention time deviation of 8 common drugs (poisons) to be±0.1 min and that of the relative retention time deviation to be±1.0%. The determination range of absolute deviation of the ion abundance ratio should be±25% when the mass concentration is LOQ or above, and the relative deviation should be±40%. When the mass concentration is below LOQ, the deviation determination range can be expanded to±35% and±50%, respectively.

Influência da idade do lodo na colmatação das membranas em um biorreator à membrana tratando esgoto sanitário / Effect of solids retention time on membrane fouling in a membrane bioreactor treating municipal wastewater

RESUMO O presente estudo avaliou o efeito da idade do lodo (θc) no potencial incrustante do licor misto em um biorreator à membrana (BRM) tratando esgoto sanitário. Tal avaliação foi conduzida em BRM construído em escala de bancada, com volume útil de 15 L, operado por 420 dias na modalidade de batelada sequencial. Durante o período experimental, foram aplicadas 3 estratégias operacionais, E-1, E-2 e E-3, em que foram testadas as idades de lodo de 80, 40 e 20 dias, respectivamente. Os resultados revelaram que a utilização da idade de lodo de 20 dias resultou em licor misto com maior potencial incrustante, apresentando, neste caso, uma velocidade de colmatação (VC) das membranas de 1,95 mbar dia-1, aproximadamente 2 vezes maior do que a observada nas idades de lodo de 80 e 40 dias. A maior colmatação observada foi atribuída a maior concentração de produtos microbianos solúveis (PMSs) no licor misto e a maior relação proteínas/polissacarídeos (PN/PS) dos flocos biológicos nesse período em questão. Por outro lado, a aplicação da idade de lodo de 80 dias resultou em menor VC das membranas do BRM, com valor de 0,82 mbar dia-1. Contudo, no período final dessa estratégia foi observado crescimento excessivo de bactérias filamentosas, que se refletiu em piora da filtrabilidade do licor misto e aumento da VC das membranas. De maneira geral, os resultados obtidos mostraram que a aplicação da idade de lodo de 40 dias resultou em licor misto com menor potencial incrustante.

ABSTRACT This study evaluated the effect of solids retention time (SRT) on membrane fouling rate in a membrane bioreactor (MBR) treating municipal wastewater. The evaluation was conducted in a membrane bioreactor built in bench scale, with a volume of 15 L, operated for 420 days in the sequential batch regime. During this period, three experimental runs were applied, E-1, E-2 and E-3, in which the solids retention time of 80, 40 and 20 days, respectively, were tested. The results showed that use of 20-days solids retention time resulted in a higher membrane fouling rate (MFR), with value of 1,95 mbar d-1, approximately two times higher than observed in the solids retention time of 80 and 40 days. The higher membrane fouling rate observed was attributed to a higher concentration of soluble microbial products (SMP) in the mixed liquor and to the higher proteins/polysaccharides ratio of the biological flocs in this period. On the other hand, the use of 80-days solids retention time resulted in a lower membrane fouling rate, with a value of 0.82 mbar d-1. However, it was observed in the final period of this experimental run an excessive growth of filamentous bacteria, which was reflected in a deterioration of the mixed liquor filterability and an increase of membrane fouling rate. Overall, the results showed that the 40-days solids retention time resulted in a mixed liquor with lower fouling propensity.

Production of Bioethanol from Sugarcane Bagasse Using Saccharomyces Cerevisiae

Ethanol is an alternative fuel derived from renewable biological resources. It's a good substitute for gasoline in spark ignition engines. In this study, the sugar cane bagasse was chemically pretreated with 1% NaOH at room temperature for 2 hours. Dilute acid H2SO4 and Aspergillus niger was used to hydrolyse the biomass to sucrose. Fermentation of the hydrolysed sample was done using Saccharomyces cerevisiae. The fermented product was purified by distillation process at 78oC, and the fraction was collected, and the ethanol was determined by measuring the specific gravity. The production of ethanol from sugar cane bagasse with Saccharomyces cerevisiae was determined after the inoculation into sample A1, A2 and B1 and B2 and highest ethanol produced were from B1 with 0.090 followed B2 0.074, A2 with 0.069% and D 0.116. The use of Saccharomyces cerevisiae gives a better yield. The result of this study can be of a better application in the large production of biofuel from sugar cane bagasse which is renewable and highly abundant, it is saving costs by recycling of wastes, and it also helps to alleviate environmental problem such as an excessive release of greenhouse gases from combustion of non-renewable fossil fuel. From the chromatograph, when the peaks spectrum wave analysed by mass spectrometer of the three volatile organic compounds, two were common to both samples, A contains the abundance of Acetic acid 22.37%, Ethyl alcohol 13.55% isobutene 64.08%. While that of Sample B contains the abundance Acetic acid 17.43%, Ethyl alcohol 7.12% and Propane 75.4.according to Pasteur this is due to Microbial oxidation of ethanol to acetic acid that decreases metabolic toxicity to the yeast cells. This study has proven the efficiency of Saccharomyces cerevisiae for the production of bioethanol.

Prevalence Of Thalassemia In Tribal Patients Attending Tertiary Care Hospital In Jharkhand

Introduction:The inherited disorders of blood include hemoglobinopathies as one of the major public health problems in India. They cause a high degree of morbidity, moderate to severe hemolytic anemia among vulnerable segments of the society like infants and children, adolescent girls, pregnant women, etc. and several deaths in India. The cumulative gene frequency of the three most predominant abnormal hemoglobins, i.e. sickle hemoglobin, hemoglobin D and hemoglobin E has been found to be 5.35% in India. Prevalence of sickle gene is found to be 0-18% in North eastern India, 0-33.5% in Western India, 22.5-44.4% in Central India and 1-40% in Southern India. The sickling disorders- HbSS, HbSD, HbSE, HbS/ βthalassemia and other compound heterozygous hemoglobinopathies are all clinically significant, as these combinations present with different manifestations and degrees of severity, making precise identification important. Automated cation-exchange High Performance Liquid Chromatography (HPLC) has emerged as an excellent screening tool for diagnosing these abnormal hemoglobins/ thalassemic states. Ÿ Aims and Objective: To determine the prevalence of different types of thalassemias and its distribution in tribal population attending the Pathology Department of RIMS Ranchi. Ÿ To correlate clinical and hematological features of thalassemias. Material and Methods: The present study entitled “Prevalence of Thalassemia in Tribal patients using High Performance Liquid Chromatography” was carried out in the Department of Pathology, Rajendra institute of Medical Sciences, Ranchi, for a period of one year (Jan 2015-Dec2015). The study was approved by Institutional Ethics Committee, Rajendra Institute of Medical Sciences. Conclusion: Out of 100 patients diagnosed with thalassemia using HPLC, 28 cases belonged to the Tribal population . In the present study the prevalence of β thalassemia trait in Tribals in Jharkhand was found to be 11%. β Thalassemia major in Tribals in Jharkhand was found to be 7%. Sickle β Thalassemia in Tribals in Jharkhand was found to be 10%. No cases of HbEβ Thalassemia in Tribals were found in Jharkhand during this period. The definite identification of disorders of hemoglobin synthesis can be achieved only by DNA analysis, but, in the Indian scenario, family studies on HPLC might be useful as there is paucity of funds, and facilities for DNA analysis are not readily available. Family study is an equally efficacious and cost effective tool. This highlights the role of premarital counseling.

Effect of Poly(Lactide-Co-Glycolide) Nanoparticles on Local Retention of Fluorescent Material: An Experimental Study in Mice

OBJECTIVE: Poly(lactide-co-glycolide) (PLGA) nanoparticles are promising materials for the development of new drug-releasing systems. The purpose of this study was to evaluate the in vivo retention time of materials loaded in nanoparticles as compared with that of the material alone by in vivo imaging in nude mice. MATERIALS AND METHODS: Mice (n = 20) were injected with 0.1 mL fluorescent material 1,1′-dioctadecyl-3,3,3′,3′ tetramethylindotricarbocyanine iodide (DiR)-loaded PLGA nanoparticles (200 nm) into the right paraspinal muscle, and the same volume of pure DiR solution was injected into the left paraspinal muscle. Fluorescence images were obtained using an in vivo optical imaging system. Fluorescent images were taken 1 day after the injection, and seven more images were taken at 1-week intervals. Image analysis was done with ImageJ program, and one region of interest was chosen manually, which corresponded to the highest signal-intensity area of fluorescence signal intensity. RESULTS: After 7 weeks, 12 mice showed a right-sided dominant signal, representing the DiR loaded PLGA nanoparticles; 5 mice showed a left-side dominant signal, representing the free DiR solution; and 3 mice showed no signal at all beginning 1 day after the injection. During the 7-week period, the mean signal intensities of the free DiR solution and DiR-loaded PLGA nanoparticles diverged gradually. On day 1, the mean signal intensity of free DiR solution was significantly higher than that of DiR-loaded PLGA (p < 0.001). Finally, by week 7, DiR-loaded PLGA express significantly high signal intensity compared with free DiR solution (p = 0.031). CONCLUSION: The results of the current study suggested that therapeutic agents bound to PLGA nanoparticles may exhibit prolonged retention times.

Effect of food improvement on the retention time of nasogastric tube in stroke patients with dysphagia / 中国实用护理杂志

Objective To explore the effect of food improvement on the retention time of nasogastric tube in stroke patients with dysphagia. Methods Sixty cases were assigned to the control group(30 cases) and the experimental group(30 cases) by random digits table method, the control group received routine nasogastric feeding, and the experimental group were given texture modified foods and thickened liquid to try to help them eating through the mouth. The feeding tube was pull out when the person in experimental group was capable of taking texture modified foods and thickened liquid without difficulty,while the tube was pull out when the person in control group was able to eat regular food and drink regular fluids. The retention time of nasogastric tube of two groups was compared. Results The retention time of nasogastric tube was(6.13±2.96)d in the experimental group and(18.93±7.58)d in the control group, there was significant difference (t =-8.162, P<0.01). Conclusions Food improvement can effectively shortenthe retention time of nasogastric tube in stroke patients with dysphagia.

Retention Time of Four Common Poisons (Drugs) by GC-MS Qualitative Analysis / 法医学杂志

Objective To investigate the maximum allowable deviation of retention time (RT) or relative retention time (RRT) between the common poisons (drugs) and standard solvent by gas chromatography-mass spectrometry (GC-MS).Methods After pretreatment with liquid-liquid extraction, four common poisons (drugs) —dichlorvos, phorate, diazepam and estazolam—were detected by full scan mode GC-MS.RT and RRT were analyzed according to combined uncertainty and expanded uncertainty. Results The expanded uncertainty of RT and RRT were 6.0× lO-4-14.1×l0-3 and 2.5 ×l0-6-5.9× lO-5 (k=3), respectively.The RT of poisons (drugs) was relatively stable in blood samples with different mass concentrations.Among dichlorvos, phorate, diazepam and estazolam, the absolute deviation and relative deviation of RT were≤0.03 min and≤0.4％, respectively, and those of RRT were≤0.003 min and≤0.3％, respectively.Conclusion The maximum allowable deviations of RT and RRT for common poisons (drugs) in blood samples are recommended to be±0.05 min and±0.5％.

Hydraulic retention time on vinasse stabilisation with limestone in the acidogenic phase of anaerobic digestion / Tempo de retenção hidráulica em vinhaça estabilizada com calcário na fase acidogênica da digestão anaeróbia

ABSTRACT: The main problem in anaerobic digestion of low-protein residues is the instability caused acidity. The use of limestone at the same time as a neutralizing agent and support material is innovative because stones wear allows the slow release of the calcium carbonate thereby eliminating dispersers. Free calcium content in the system was measured in two plug flow reactors filled with vinasse at initial pH of 4.50. The proportion of 1.8 tonnes of limestone per m³ of vinasse was evaluated at the Hydraulic Retention Times (HRT) of 24, 48, 72, 96 and 120 hours, allowing stabilisation at 96 hours. The ratio of Volatile Acids/Total Alkalinity (VA/TA) ranged from 0.2 to 0.4 and the pH reached 7.0, at the HRT of 120 hours. Increasing the HRT also increased the volatile total solids (VTS) and fixed total solids (TFS) in a similar profile to the measured free calcium content, but calcium remained at the appropriate level of 100 to 250mg l-1. The proportion of limestone/vinasse was adequate to ensure stabilisation, but it is not recommended to reduce the HRT below 96 hours due to the risk of compromising the stability of the anaerobic system.

RESUMO: O maior problema na digestão anaeróbia de resíduos de baixo teor de proteína é a instabilidade por acidez. O uso de calcário ao mesmo tempo como agente neutralizador e material suporte é inovador porque permite eliminar o dosador pois o desgaste das pedras permite a liberação lenta do carbonato de cálcio. O teor de cálcio livre no sistema foi medido em dois reatores tipo Plug flow, preenchidos com vinhaça com pH inicial de 4,50. A proporção de 1,8 toneladas de calcário por m³ de vinhaça foi avaliada com os Tempos de Retenção Hidráulica (TRH) de 24, 48, 72, 96 e 120 horas, permitindo a estabilização em 96 horas. Com um TRH de 120 horas, a relação de Ácidos Voláteis/Alcalinidade (AV/AC) variou de 0,2 à 0,4 e o pH atingiu 7,0. Aumentando o TRH também aumentaram os sólidos voláteis totais (SVT) e sólidos totais fixos (STF) em um perfil semelhante ao teor de cálcio livre medido, mas mantendo níveis adequados de 100 a 250mg L-1. A proporção de calcário/vinhaça mostrou-se adequada para garantir a estabilização, mas não se recomenda a redução do TRH abaixo de 96 horas devido ao risco de comprometer a estabilidade do sistema anaeróbio.

Avaliação do comportamento hidrodinâmico de reator anaeróbio de manta de lodo e fluxo ascendente com diferentes configurações do sistema de distribuição do afluente utilizando fluidodinâmica computacional / Hydrodynamic performance evaluation of an upflow anaerobic sludge blanket reactor with different configurations of the influent distribution system using computational fluid dynamics

RESUMO Compreender o comportamento hidrodinâmico de reatores biológicos pode auxiliar na detecção de problemas associados a falhas operacionais e de projeto, situações que prejudicam a eficiência do tratamento. Neste artigo, realizaram-se simulações da fluidodinâmica computacional (CFD) de escoamento de duas fases sólida-líquida de um reator anaeróbio de manta de lodo e fluxo ascendente (UASB), em escala piloto (160 L), com tempo de detenção hidráulica (TDH) de 10 h e vazão de 16 L.h-1. Um modelo Euler-Euler simplificado foi formulado para simular o comportamento hidrodinâmico da zona de reação, influenciada pela configuração do sistema de distribuição do afluente. Foram avaliadas quatro configurações do sistema de distribuição do afluente no reator: uma entrada na parte central (1) e duas entradas centrais (2), de fluxo ascendente; duas entradas nas laterais (3), de fluxo radial; e três entradas de fluxo descendente (4), utilizando geometrias bidimensionais e tridimensionais para verificar a formação de zonas mortas, curtos-circuitos hidráulicos e caminhos preferenciais. As melhores características hidrodinâmicas e a melhor distribuição do afluente foram verificadas na configuração 4, com melhor perfil de mistura do lodo com a fase líquida, na comparação com as demais configurações. Foi notada formação de vórtices na parte inferior do reator com maior concentração do lodo anaeróbio nessa configuração e de caminhos preferenciais nas laterais do reator na configuração 3, indicando mistura ineficiente do afluente com o lodo anaeróbio. O modelo demonstrou que a configuração do sistema de distribuição do afluente influencia significativamente o comportamento hidrodinâmico do reator UASB.

ABSTRACT Understanding the hydrodynamics behavior of biological reactors can help in the detection of problems related to operational failures and design that adversely affect the efficiency of the treatment. In this paper, computational fluid dynamics (CFD) simulations of two-phase liquid-solid flow were carried out in an upflow anaerobic sludge blanket reactor in pilot scale (160 L), with hydraulic retention time (HRT) of 10 h and flowrate 16 L.h-1. The Euler-Euler approach was formulated to simulate the reaction zone hydrodynamics. Four configurations of the influent distribution system in the reactor were evaluated: one central inlet (1) and two central inlets (2), upflow; two lateral inlets (3), radial flow; and three inlets, downflow (4), using two and three-dimensional geometries to verify the formation of dead zones, hydraulic short-circuiting and preferential pathways. Better influent distribution and greater mixture profile of the sludge with the liquid phase were found in the configuration 4, compared to the others by the formation of vortices in the bottom part of the reactor with higher concentration of anaerobic sludge. Formation of preferential pathways was noted in the lateral inlets of the reactor in the configuration 3, indicating an inefficient mixture of the influent with the sludge. The model demonstrates that the configuration of the influent distribution system significantly influences the hydrodynamics behavior of the UASB reactor.

Eficiência na remoção de NAT, DBO e DQO utilizando reator aeróbio de leito fluidizado com circulação em tubos concêntricos associado ao decantador de coluna em uma produção intensiva de tilápia / Removal efficiency of TAN, BOD and COD by using aerobic fluidized bed reactor with circulation in concentric tubes associated to a column settler in intensive production of tilapia

RESUMO O desenvolvimento da aquicultura intensiva é acompanhado de um crescente impacto ambiental produzido pelos efluentes gerados. Os sistemas de recirculação para aquicultura (SRA) são uma alternativa compacta e trabalham com elevadas densidades de estocagem e menores volumes de água. Foi utilizado um decantador de coluna (DC) associado ao reator aeróbio de leito fluidizado com circulação em tubos concêntricos (BAS-CT) com tempo de retenção hidráulica (TRH) de 0,55 e 0,20 h respectivamente, num SRA com tilápias de 0,32 kg de peso médio e densidade de estocagem de 33,1 kg.m-3 em relação à remoção do nitrogênio amoniacal total (NAT), demanda bioquímica de oxigênio (DBO) e demanda química de oxigênio (DQO). As eficiências na remoção de NAT, DBO e DQO foram 35,2, 48,0 e 64,9%, respectivamente. No uso de DC com o BAS-CT, obteve-se bom desempenho, com baixos TRH no tratamento do efluente.

ABSTRACT The development of intensive aquaculture is accompanied by an increasing environmental impact produced by the wastewater generated. The recirculating aquaculture systems (RAS) are a compact alternative and manage high stocking densities and lower volumes of water. It was used a column settler (CS) associated with aerobic fluidized bed reactor (BAS-CT) with hydraulic retention time (HRT) of 0.55 and 0.20 h respectively, in RAS with tilapias with average weight of 0.32 kg and storage density of 33.1 kg.m-3 regarding the removal of total ammonia nitrogen (TAN), biochemical oxygen demand (BOD) and chemical oxygen demand (COD). The removal efficiencies of TAN, BOD and COD were 35.2, 48.0 and 64.9%, respectively. The use of CS with the BAS-CT showed a good performance with low HRT in the treatment of this effluent.

Preparation and properties of thermosensitive in situ gel for ophthalmic formulation containing pearl hydrolyzate / 药学学报

The study was designed to generate an ophthalmic thermosensitive in situ gel with improved mechanical and mucoadhesive properties that may prolong the retention time to enhance the bioavalability of pearl hydrolyzate. The gene was comprised of poloxamer 407, poloxamer188 and Carbopol 934, which were optimized by central composite design and response surface methodology. The rheological properties, transcorneal permeability, retention time and in vitro release behaviors of the optimal gel formulation were investigated. The gel was Newtonian liquid at 25℃ and performed as a semisolid gel with non-Newtonian liquid property with a gelation time of 13 s at 35℃. Compared with a conventional eye drops, the ophthalmic in situ gel exhibited a sevenfold increase in retention with a sustained release behavior, which was observed with suitable permeability coefficient at 5.58 cm·s-1. In conclusion, the new gel of pearl hydrolyzate prolonged the release duration of drug, which may decrease the frequency of administration of pearl hydrolyzate. kilometers with ecological similarity between 20% and 40%, mainly in Yunnan, Guangxi, Guangdong, Guizhou, Hainan, Sichuan, Fujian and Chongqing. The climate factors mainly affecting the distribution of Panax notoginseng (Burk.) F. H. Chen were precipitation of warmest quarter, SD of temperature seasonality, altitude, isothermality, coefficient of variation of precipitation seasonality, mean temperature of monthly, precipitation of driest month, reference bulk density of soil and soil texture.

Análise comparativa dos efeitos da carga orgânica e do tempo de detenção hidráulica na digestão anaeróbia mesofílica de lodo adensado de estação de tratamento de esgoto / Comparison of organic loading rate and hydraulic retention time effects on the mesophilic anaerobic digestion of thickened waste activated sludge

RESUMO Esta pesquisa comparou o desempenho de um digestor anaeróbio de lodo sob diferentes estratégias operacionais. Foi avaliada a influência do aumento da carga orgânica volumétrica (COV) (OP I) e o efeito da redução do tempo de detenção hidráulica (TDH) (OP II e OP III) no processo anaeróbio. As cargas aplicadas variaram entre 0,5 e 4,5 kgSV.m-3.d-1 e o TDH foi reduzido de 15 a 5 dias. Produção de gás metano, degradação do material orgânico e a diversidade microbiana foram utilizadas para medição e comparação do desempenho do processo. Foram necessários períodos de aclimatação a cada nova COV aplicada o que levou às instabilidades na remoção de SV e DQO do lodo. A operação com TDH entre 7 e 5 dias apresentou as maiores eficiências de remoção de SV, superiores a 70%, o que influenciou positivamente na estabilidade do processo. As COV aplicadas de 2,5 e 3,5 kgSV.m-3.d-1 resultaram nas maiores produções de metano durante a OP I. Para TDH inferiores a sete dias a produção de CH4 foi prejudicada apesar da existência de microorganismos metanogênicos atuantes no digestor. Comparativamente, a estratégia de redução do TDH resultou em um melhor desempenho do sistema que a fixação da COV. Quanto menor o TDH aplicado, melhor os resultados obtidos na operação do digestor, sugerindo que a eficiência do processo é otimizada em sistemas de alta carga com operação em baixos tempos de detenção hidráulica.

ABSTRACT This study compared the performance of a pilot anaerobic sludge digester under different operating strategies. The influence of increasing organic loading rate - OLR (OP I) and the effect of hydraulic retention time - HRT reduction (OP II and OP III) in anaerobic process were evaluated. The applied loads ranged between 0.5 and 4.5 kgSV.m-3.d-1; HRT was reduced from 15 to 5 days. Production of methane, organic matter degradation and microbial diversity were used to measure and compare the system´s performance. Acclimation periods were taken for each new OLR applied, leading to instabilities in sludge VS and COD removals. The experimental time with HRT between 7 and 5 days showed the highest VS efficiency removals (higher than 70%), which positively influenced process stability. The applied OLR of 2.5 and 3.5 kgVS.m-3.d-1 resulted in higher yields of methane during OP I. CH4 production showed impaired with HRT lower than 7 days, although it was observed active methanogenic microorganisms in the digester. Comparatively, HRT reduction resulted in a better system performance than the increasing OLR approach. The lower HRT applied, the better the results obtained in the operation of the digester, suggesting that the process efficiency is optimized with high load operation at low hydraulic retention times.

Effects of Different Times of Needle Retention on Cognitive Function in Vascular Cognitive Impairment No Dementia / 上海针灸杂志

Objective To investigate the effects of different times of needle retention on cognitive function in patients with vascular cognitive impairment no dementia (VCIND). Methods One hundred and four VCIND patients were randomly allocated to group A of 35 cases, group B of 34 cases and group C of 35 cases. All the three groups received acupuncture plus medication. Of them, group A was given scalp acupuncture with 30 min retention of needles;group B, with 1 hr retention of needles;group C, with 10 hrs retention of needles. The Montreal Cognitive Assessment (MoCA) score and the ADL score were recorded in the three groups of patients before and after treatment. Results There were statistically significant pre-/post-treatment differences in the MoCA score and the ADL score in every group (P<0.05). There were statistically significant post-treatment differences in the MoCA score and the ADL score between group A or B and group C (P<0.05). Conclusions Acupuncture is an effective way to treat VCIND. It can improve cognitive function in the patients. Scalp acupuncture with 10 hrs retention of needles has a more marked effect.

Study on UHPLC Fingerprints of Psoralea corylifolia L / 世界科学技术-中医药现代化

This study was aimed to establish the ultra high performance liquid chromatography (UHPLC) fingerprints of Psoralea corylifolia L. The separation was achieved on a Shim-pack XR-ODS Ⅲ column (50 mm í 2.0 mm, 1.6μm) by gradient elution with acetonitrile-0.2% glacial acetic acid solution as the mobile phase. The flow rate was 0.1 mL·min-1 and the measurement wavelength was 246 nm. The temperature of the column was 45oC. The results showed that the UHPLC fingerprint of P. corylifolia L. was established and 10 characteristic common peaks were found, among which 6 peaks were recognized by comparing with reference substances. It was concluded that the method was rapid, reliable and reproducible. The established fingerprint can provide references for the study of sub-stance basis and quality control of P. c orylifolia L.