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1.
Environ Res ; 246: 118035, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199477

RESUMO

Nitrification of ammoniacal nitrogen (N-NH4+) to nitrate (N-NO3-) was investigated in a lab-scale sequencing batch reactor (SBR) to evaluate its efficiency. During the nitrification process the removal of N-NH4+ reached 96%, resulting in 73% formation of N-NO3-. A lineal correlation (r2 = 0.9978) was obtained between the concentration of volatile suspended solids (VSS) and the maximal N-NO3- concentration at the end of each batch cycle under stationary state. The bacterial taxons in the initial inoculum were identified, revealing a complex diverse community mainly in the two major bacterial phyla Proteobacteria and Actinobacteria. The FAPROTAX algorithm predicted the presence in the inoculum of taxa involved in relevant processes of the nitrogen metabolism, highlighting the bacterial genera Nitrospira and Nitrosomonas that are both involved in the nitrification process. A kinetic model was formulated for predicting and validating the transformation of N-NH4+, N-NO2- and N-NO3- and the removal of organic and inorganic carbon (TOC and IC, respectively). The results showed how the increase in biomass concentration slowed down the transformation to oxidised forms of nitrogen and increased denitrification in the settling and filling stages under free aeration conditions.


Assuntos
Desnitrificação , Nitrificação , Reatores Biológicos/microbiologia , Genômica , Bactérias/genética , Bactérias/metabolismo , Nitrogênio/análise , Esgotos/microbiologia
2.
J Environ Manage ; 326(Pt A): 116741, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36399884

RESUMO

In this study, five urban WWTPs (Wastewater Treatment Plant) with different biological treatment (Extended Aeration Activated Sludge - EAAS; Rotating Biological Contactor - RBC), wastewater type (Urban; Industrial) and size, were jointly evaluated. The aim was twofold: (1) to analyze and compare their odor emissions, and (2) to identify the main causes of its generation from the relationships between physico-chemical, respirometric and olfactometric variables. The results showed that facilities with EAAS technology were more efficient than RBC, with elimination yields of organic matter higher than 90%. In olfactometric terms, sludge managements facilities (SMFs) were found to be the critical odor source in all WWTPs compared to the Inlet point (I) or Post primary treatment (PP), and for seasonal periods with ambient temperature higher than 25 °C. Moreover, the global odor emissions quantified in all SMFs revealed that facilities with EAAS (C-WWTP, V-WWTP and Z-WWTP) had a lower odor contribution (19,345, 14,800 and 11,029 ouE/s·m2, respectively) than for those with RBC technology (P-WWTP and NC-WWTP) which accounted for 19,747 ouE/s·m2 and 80,061 ouE/s·m2, respectively. In addition, chemometric analysis helped to find groupings and differences between the WWTPs considering the wastewater (71.27% of total variance explained) and sludge management (64.52% of total variance explained) lines independently. Finally, odor emissions were adequately predicted from the physico-chemical and respirometric variables in the wastewater (r2 = 0.8738) and sludge (r2 = 0.9373) lines, being pH, volatile acidity and temperature (wastewater line), and pH, moisture, temperature, SOUR (Specific Oxygen Uptake Rate) and OD20 (Cumulative Oxygen Demand at 20 h) (sludge line) the most influential variables.


Assuntos
Odorantes , Esgotos , Águas Residuárias , Espanha , Tecnologia , Oxigênio
3.
J Environ Manage ; 294: 113044, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130131

RESUMO

The influence of bed material on the odor removal performance of a biofilter was studied. A compost-wood biofilter and a wood biofilter were treated with a gaseous stream contaminated with butyric acid and comparatively evaluated at pilot scale using olfactometric, physico-chemical and microbiological approaches. The variables analyzed in both biofilters were correlated with specific families of their microbiota composition. In addition to a higher nutrients content (nitrogen and phosphorus), the compost-wood biofilter registered maximum values in number of aerobic microorganisms (3.6·108 CFU/g) and in aerobic microbiological activity (≈40 mg O2/g VS of cumulative oxygen demand at 20 h). This may explain the higher performance of this biofilter compared to the wood biofilter, withstanding odor loads of up to 1450 ouE/m2·s with odor removal efficiencies close to 100%. The analysis of the microbial community showed that Actinobacteria, particularly the mostly aerobic Microbacteriaceae family, might play an important role in butyric acid degradation and hence reduce odor impact. The multidisciplinary analysis carried out in this work could be a very useful strategy for the optimal design of biofiltration operations.


Assuntos
Compostagem , Filtração , Biodegradação Ambiental , Ácido Butírico , Gases , Madeira
4.
Environ Res ; 190: 110057, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32805248

RESUMO

The objective of this study is to evaluate comparatively the odor removal efficacy of two biofilters operated under different conditions and to identify taxonomically the microbial communities responsible for butyric acid degradation. Both biofiltration systems, which were filled with non-inoculated wood chips and exposed to gas streams containing butyric acid, were evaluated under different operational conditions (gas airflow and temperature) from the physical-chemical, microbiological and olfactometric points of view. The physical-chemical characterization showed the acidification of the packing material and the accumulation of butyric acid during the biofiltration process (<60 days). The removal efficacy was found to be 98-100% during the first 20 days of operation, even at high odor concentration. Changes in the operational temperature increased the odor load factor from 400 to 1400 ouE/m2·s, which led to the reduction of microbiota in the packing material, and a drastic drop of the odor removal efficacy. However, the progressive increase in gas airflow improved the biodegradation efficacy of butyric acid up to 88% with odor loadings as high as 33,000 ouE/m3, while a linear relationship between odor inlet load and removal capacity was also found. The analysis of the microbial community showed that Proteobacteria was the most abundant phylum along the biofiltration time (58-92%) and regardless of the operational conditions. Finally, principal component analysis applied to the physical-chemical and microbiological data set revealed significant differences between the two biofilters under study.


Assuntos
Filtração , Microbiota , Biodegradação Ambiental , Ácido Butírico , Odorantes
5.
Environ Res ; 183: 109168, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32004831

RESUMO

Biological techniques are widely used to treat gaseous streams derived from waste treatment plants. The generation of volatile organic compounds (VOCs) is one of the principal pollution sources in composting facilities from which nuisance odours are released. In addition, the generation of photochemical smog with other gases such as NOX can produce ozone at ground level due to their photochemical ozone creation potential (POCP). In this work, the performance of an industrial biofilter was evaluated from an environmental point of view. Specifically, this study evaluated the potential impact in terms of photochemical oxidation and odour emission derived from composting in a vessel under four different aeration conditions. Gas chromatography-time-of-flight mass spectrometry (GC-TOFMS) was used to perform the chemical characterisation of the gaseous streams, while dynamic olfactometry was used to carry out the sensorial analysis. A total of 95 compounds belonging to 12 different families of VOCs were selected. Principal component analysis revealed the influence of each VOC family on each impact category and explained 88% of the total variance. Multivariate regression was used to study the correlation between photochemical oxidation and odour impact, which has never been reported before. The correlations obtained (r ≥ 0.97) evidenced the direct relationship between these two impacts. Photochemical oxidation and odour emission were proven to be important environmental impacts derived from composting facilities, whose abatement might be carried out by biofiltration systems.


Assuntos
Poluentes Atmosféricos , Compostagem , Odorantes , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas , Olfatometria
6.
J Environ Manage ; 247: 205-213, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247367

RESUMO

Sewage sludge and bulking agent with small proportions of eggplant waste (EP) (4.7 and 8.6%) were co-composted at full scale to evaluate the feasibility of their joint valorization and to reduce the odorous impact during composting. In this sense, physico-chemical, respirometric and olfactometric variables were monitored throughout the co-composting process. The physico-chemical variables studied were related to each other to evaluate their effect on the quality of the final product and the odoriferous impact. It was observed that the reduction in nitrogen concentration was not parallel to the removal of organic matter, which influenced the odor concentration emitted. Furthermore, during the hydrolytic stage of the co-composting process, the odor concentration was lower when the agricultural waste content was highest (8.6% EP: 6317 and 8192 ouE/m3) in comparison with the lowest concentration of EP (4.7% EP: 9214 and 14720 ouE/m3) or without the addition of EP (reference composting pile: 10200 and 22500 ouE/m3). Although sewage sludge is more biodegradable than eggplant waste, the co-composting process was carried out under suitable conditions. Approximately 90 days were required to obtain a stabilized compost. Consequently, co-composting might be a suitable alternative to valorize EP and reduce the odoriferous impact of sewage sludge, with the consequent economic, social and environmental benefits.


Assuntos
Compostagem , Solanum melongena , Estudos de Viabilidade , Esgotos , Solo
7.
Environ Res ; 167: 739-750, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30241730

RESUMO

The aim of this study was to assess the odor immission derived from full-scale composting of different abundant and highly pollutant organic waste: sewage sludge with bulking agent (SL), sewage sludge pretreated through anaerobic digestion and supplemented with bulking agent (SL-AD), and market waste with olive leaves (MW-OL). The combination of dynamic olfactometry and Gaussian dispersion modeling allowed both the quantification of odor emissions from each waste and the evaluation of their global odorous impact in nearby urban areas. Wind speed, summer and winter seasons, and atmospheric conditions were considered in the dispersion model. The results revealed that high wind speed (2.6 m/s) increases the global odor immission in summer season, independently of atmospheric stability. However, the maximum odor immission concentration recommended for composting process was not exceeded in any case, which depends on each country/region. The experimental results also enable to evaluate the influence of several physico-chemical variables on odor emissions derived from composting. The removal of nitrogen and volatile solids was the main cause for odor generation. Moreover, the microbiological activity of each substrate was monitored throughout the process and different percentages of biodegradability were quantified depending on the type of substrate and pretreatment applied.


Assuntos
Compostagem , Odorantes , Olfatometria , Esgotos , Solo
8.
J Environ Manage ; 215: 185-194, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29571099

RESUMO

In an economic context marked by increasing energy costs and stricter legislation regarding the landfill disposal of wastewater treatment plant (WWTP) sewage sludge, and where biomethanization is difficult to implement in small WWTPs, an efficient alternative is required to manage this polluting waste. This study shows that autothermal thermophilic aerobic digestion (ATAD) is a feasible technique for treating sewage sludge in small- and medium-sized towns. The experiments were carried out at pilot scale on a cyclical basis and in continuous mode for nine months. The main results showed an optimal hydraulic retention time of 7 days, which led to an organic matter removal of 34%. The sanitized sludge meets the microbial quality standards for agronomic application set out in the proposed European sewage sludge directive. An economic assessment for the operation of ATAD technology was carried out, showing a treatment cost of €6.5/ton for dewatered sludge.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Reatores Biológicos
9.
J Environ Manage ; 196: 387-393, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28334677

RESUMO

In this research study, the co-composting process of a waste mixture containing strawberry extrudate, fish waste, sewage sludge and bulking agent (SEFW, 190:1:22:90 ratio) was carried out in a dynamic-solid respirometer at pilot scale. The aerobic biodegradability of the mixture was previously ensured in a static-liquid respirometer. The advantages and drawbacks of the SEFW co-composting process were subsequently identified through the determination of respirometric activity and the physical-chemical characterization of the waste, as well as the monitoring of odor emissions. The evolution of the physical-chemical variables showed that pH increased slightly and that the organic matter concentration, expressed as volatile solids (VS, %) or oxidable organic carbon (COXC, %), decreased by around 15% in both cases and by approximately 56% in its biodegradable form (total organic carbon, TOC, %). The low odor emission rate (OER) in the least favorable scenario (the maximum odor generation) during SEFW composting was 1.59 ouE/s, whereas this figure reached 3.52 ouE/s when only the organic fraction of municipal solid waste (OFMSW) was composted. Consequently, the co-composting of SEFW is more favorable in terms of odor emission and permits the simultaneous treatment of different types of waste.


Assuntos
Resíduos Industriais , Esgotos , Gerenciamento de Resíduos , Carbono , Solo , Resíduos Sólidos , Temperatura
10.
J Environ Manage ; 177: 231-9, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27107391

RESUMO

Sewage sludge generated in the activated sludge process is a polluting waste that must be treated adequately to avoid important environmental impacts. Traditional management methods, such as landfill disposal or incineration, are being ruled out due to the high content in heavy metal, pathogens, micropolluting compounds of the sewage sludge and the lack of use of resources. Anaerobic digestion could be an interesting treatment, but must be improved since the biomethanisation of sewage sludge entails low biodegradability and low methane production. A microwave pre-treatment at pilot scale is proposed to increase the organic matter solubilisation of sewage sludge and enhance the biomethanisation yield. The operational variables of microwave pre-treatment (power and specific energy applied) were optimised by analysing the physicochemical characteristics of sewage sludge (both total and soluble fraction) under different pre-treatment conditions. According to the variation in the sCOD and TN concentration, the optimal operation variables of the pre-treatment were fixed at 20,000 J/g TS and 700 W. A subsequent anaerobic digestion test was carried out with raw and pre-treated sewage sludge under different conditions (20,000 J/g TS and 700 W; 20,000 J/g TS and 400 W; and 30,000 J/g TS and 400 W). Although stability was maintained throughout the process, the enhancement in the total methane yield was not high (up to 17%). Nevertheless, very promising improvements were determined for the kinetics of the process, where the rG and the OLR increased by 43% and 39%, respectively, after carrying out a pre-treatment at 20,000 J/g TS and 700 W.


Assuntos
Reatores Biológicos , Micro-Ondas , Esgotos , Gerenciamento de Resíduos/métodos , Anaerobiose , Cinética , Metano/análise , Metano/química
11.
Water Environ Res ; 85(4): 346-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23697239

RESUMO

The viability of an integrated coagulation-flocculation and aerobic treatment for purifying wastewater derived from a sauce manufacturing industry was evaluated. The best coagulation-flocculation results were obtained at alkaline pH, showing the greatest turbidity removal efficiency (greater than 90%) and a total chemical oxygen demand (COD) removal of approximately 80%, Additionally, experiments at alkaline pH reduce the reagent requirements (coagulant concentration of 0.4 mL/L and flocculant concentration of 4.0 mL/L) providing a consequent economic benefit as compared to experiments at neutral and acidic pH. Another set of experiments was conducted in a sequencing batch reactor to evaluate the aerobic biodegradability of the remnant dissolved organic matter. The effluent from the physical-chemical pre-treatment at alkaline pH again showed the highest biodegradability (76%), with a global COD total removal of 98%. The results showed that the combination of both techniques could be a viable alternative to efficiently treat wastewater derived from sauce manufacturing.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Aerobiose , Concentração de Íons de Hidrogênio , Águas Residuárias/análise , Águas Residuárias/química
12.
Environ Technol ; 44(4): 501-511, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34469279

RESUMO

A large quantity of lignocellulosic biomass is generated annually across the world which leads to environmental pollution and requires valorization. This study investigated the effect of hydrothermal pretreatment on the anaerobic digestion and co-digestion of the residual pepper plant and eggplant with a focus on kinetics. Two thermal hydrolysis rates were observed, with the optimal conditions for the hydrothermal pretreatment of lignocellulosic biomass being 120°C for 40 min. Subsequently, single and combined biomethanization was successfully carried out in laboratory-scale completely stirred tank reactors at mesophilic temperature (35°C). A high increase in methane production was observed after the pretreatment of the pepper plant and eggplant. The pretreated and co-digested wastes led to an optimal methane yield of 79 ± 23 mL CH4/g VS. The modified Gompertz model was used to fit the cumulative methane production of the pretreated lignocellulosic substrates. The kinetic model adequately reproduced the experimental results and might be considered a useful tool to simulate the biomethanization behaviour of complex organic substrates.


Assuntos
Solanum melongena , Biomassa , Anaerobiose , Cinética , Metano , Biocombustíveis , Reatores Biológicos
13.
Artigo em Inglês | MEDLINE | ID: mdl-39070071

RESUMO

This study investigates the effects of radiofrequency ablation (RFA)-created lesions on an explanted human heart in wedge preparation by simultaneous endo and sub-endo optical mapping. The heart in Langendorff perfusion was ablated under 40 W. The ventricle was stained with Vm sensitive dye Di-4-ANBDQPQ and two excitation light bands of different penetration depths were used (red = 660 nm, green = 525 nm) to perform a conduction velocity (CV) difference analysis for identification of CV alter-nans. The relative change in fluorescence (ΔF/F) traces were analyzed before and after ablation. Local activation time (LAT) was determined by the 50% approach. Local CV was obtained using the circle method, and RFA created lesions were characterized by examining the CV alternans correlated with transmural heterogeneities. The presence of CV alternans results from reduced excitability in a non-homogeneous lesion consisting of excitable and non-excitable cells. The absence of CV alternans in optical mapping with green light and their presence with deep-red light illustrates incomplete ablation across the ventricular wall or non-homogeneous ablation in the mid-myocardial layer. The presence of an intramural scar impairs the efficacy of the RFA procedure, suggesting a need for alternative ablations strategies.

14.
Environ Technol ; 42(23): 3618-3626, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32114938

RESUMO

Grapes are one the world's leading fruit crops, with close to 77 million tonnes harvested per year. Grapes are commonly used to produce wine; a process which generates different wastes such as grape mark waste (skins, seeds and stalks), lees and other residues. This study evaluates the treatment of winery waste derived from ecological cultivation by anaerobic digestion to produce energy in the form of methane. Grape marc waste, Verdejo and Pedro Ximenez (PX) wine lees were digested under stable conditions at mesophilic conditions. The PX lees showed the highest methane yield production (433 LSTP CH4/kg VS) with a maximum OLR of 4.58 kg VS/m3·d. In the evaluated range the process was stable with a range of biodegradability of 51-79%. Due to different types of winery waste are generated at consecutive stages of the main production process, the sequential treatment of PX lees, Verdejo lees and grape marc waste in the same anaerobic digester could be an interesting option. This procedure would facilitate the management of the residual streams generated in wineries during the year and promotes the circular economy in the Montilla-Moriles Protected Designation of Origin.


Assuntos
Vitis , Vinho , Anaerobiose , Digestão , Metano
15.
Sci Total Environ ; 754: 142237, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33254922

RESUMO

Odor emissions from wastewater treatment plants (WWTPs) have always been a public concern. In this work, the physico-chemical, olfactometric and textural characterization of granular active carbon (GAC) used by an urban WWTP as a deodorization system, as well as the chromatographic quantification of the retained odoriferous compounds, have been carried out. These techniques have allowed an integral evaluation of the contaminated GAC and the characterization of the retained gaseous emission from four different stages of the wastewater treatment (pretreatment header: GAC-1; sand and fat removal: GAC-2; sludge thickening: GAC-3; sludge dehydration: GAC-4). A larger amount and variety of retained odoriferous compounds were found in GAC samples from the wastewater line deodorization (GAC-1 and GAC-2) after the same operation time (one year), GAC-1 being the adsorbent bed that retained the highest mass of volatile compounds (approximately 150µg/g GAC). Furthermore, some variables such as the removed specific odor concentration and free micropore volume were inversely correlated (R2=0.9945). The analysis of odor contribution showed that sulfur-containing compounds were the major odor contributors (61-97%). However, hydrogen sulfide cannot be considered a key odorant in this particular WWTP, since the elimination of this compound does not reduce the significant contribution of other (organic) sulfur compounds to the global odor (especially dimethyl disulfide). Consequently, multi-technical analysis might be a suitable alternative to better understand odor removal by GAC adsorption.

16.
J Hazard Mater ; 408: 124939, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33383449

RESUMO

Water shortage and low organic carbon content in soil limit soil fertility and crop productivity. The use of desalinated seawater is increasing as an alternative source of irrigation water. However, it has a high boron (B) content that could cause toxicity in the plant-soil microbial system. Here, we evaluated the responses of the soil microbiota and lemon trees to 3 irrigation B doses (0.3, 1, and 15 mg L-1) under two types of soil management (conventional, CS; and organic, OS) in a 180-days pot experiment. High B doses promoted B accumulation in soil, reaching harmful concentrations that affected soil biodiversity. Our results suggest a close interaction between B and organic labile fractions that increased B availability in soil solution. Besides, B addition to soil impacted on microbial biomass. The bacterial community showed sensitivity to the B dose. Organic amendment did not increase B soil adsorption but it favored B plant uptake. The highest B dose had a detrimental impact on plant physiology, finally resulting lethal for the plants. Our study provides a comprehensive assessment of the microbes-plant interactions in soils irrigated with water with high B content. This will be fundamental in the design of future fertirrigation strategies.


Assuntos
Microbiota , Solo , Biomassa , Boro , Microbiologia do Solo
17.
Waste Manag ; 102: 76-84, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31669677

RESUMO

Plant residues are an important source of organic matter that can be degraded by aerobic or anaerobic biological processes. However, due to the presence of lignocellulosic material, these residues are not easily biodegradable. Greenhouse crops, such as pepper and eggplant, generate large amounts of this type of waste after harvesting. In this study, a hydrothermal pretreatment was applied at 120 °C and different times to evaluate the enhancement of C and N solubilization in these residues. The highest solubilization of C was obtained at 40 min, as no significant increases were observed at higher times (100% and 68% for pepper plant [PP] and eggplant [EP], respectively). The solubilization of N shows a linear behavior (PP r2 = 0.9670 and EP r2 = 0.9395). Aerobic and anaerobic biodegradability were also evaluated, with better results found for the anaerobic digestion of the pretreated substrates. The nutrients balance with anaerobic co-digestion of both pretreated substrates (50:50% wt) improved methane production by 1.4 and 1.8 with respect to the substrates individually.


Assuntos
Biocombustíveis , Solanum melongena , Anaerobiose , Reatores Biológicos , Lignina , Metano
18.
Injury ; 51 Suppl 1: S12-S18, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32115206

RESUMO

BACKGROUND: The risk of femoral neck fracture progressively increases with age. However, the reasons behind this consistent increase in the fracture risk can't be completely justified by the decrease in the bone mineral density. The objective of this study was to analyze the correlation between various bone structural features and age. STUDY DESIGN & METHODS: A total of 29 consecutive patients who suffered an intracapsular hip fracture and underwent joint replacement surgery between May 2012 and March 2013 were included in this study. A 2 cm × 1 cm Ø cylindrical trabecular bone sample was collected from the femoral heads and preserved in formaldehyde. Bone mineral density (BMD), microarchitecture, organic content and crystallography were analyzed using a Dual-energy X-ray absorptiometry scan, micro-CT scan, and high resolution magic-angle-spinning-nuclear magnetic resonance (MAS-NMR), respectively. Statistical correlations were made using Spearman´s or Pearson´s correlation tests depending on the distribution of the continuous variables. RESULTS: The mean patient age was 79.83 ± 9.31 years. A moderate negative correlation was observed between age and the hydrogen content in bone (1H), which is an indirect estimate to quantify the organic matrix (r = -0.512, p = 0.005). No correlations were observed between BMD, trabecular number, trabecular thickness, phosphorous content, apatite crystal size, and age (r = 0.06, p = 0.755; r = -0.008, p = 0.967; r = -0.046, p = 0.812; r = -0.152, p = 0.430, respectively). A weak positive correlation was observed between Charlson´s comorbidity index (CCI) and c-axis of the hydroxiapatite (HA) crystals (r = -0.400, p = 0.035). CONCLUSION: The femoral head relative protein content progressively decreases with age. BMD was not correlated with other structural bone parameters and age. Patients with higher comorbidity scores had larger HA crystals. The present results suggest that the progressive increase in the hip fracture risk in elderly patients could be partially explained by the lower bone protein content in this age group.


Assuntos
Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Fraturas do Colo Femoral/diagnóstico por imagem , Cabeça do Fêmur/patologia , Fraturas por Osteoporose/diagnóstico por imagem , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Fraturas do Colo Femoral/fisiopatologia , Humanos , Masculino , Fraturas por Osteoporose/fisiopatologia , Microtomografia por Raio-X
19.
Environ Technol ; 40(5): 564-575, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29072111

RESUMO

This study evaluates the feasibility of using simultaneous mass balances of different nutrients as a tool for optimizing feeding composition in anaerobic digestion. Different ratios, among them total chemical oxygen demand/total Kjeldahl nitrogen (TCOD/TKN) and soluble chemical oxygen demand/TCOD (SCOD/TCOD), were assessed. The TCOD/total volatile solids (TVS) ratio was 1.73 kg O2/kg TVS, while, with the exception of the sewage sludge, pig slurry and animal wastes, a linear relationship was established between phosphorus and nitrogen (0.06 kg P/kg TKN (R2 = 0.9045)). The study was applied to different mixtures of waste (cucumber, quince, tomato, strawberry waste, vinasse, glycerol, tomato plant, pig slurry, sewage sludge, fish waste, landfill leachate and viscera). The mass balance was performed for 50 mixtures chosen at random, containing three different wastes. After evaluating the theoretical optimal values determined by the mass balances, the most promising data were compared with the experimental results of the anaerobic co-digestion of one of the three waste mixtures. As predicted by the mass balances, the codigestion of glycerol, strawberry extrudate and fish waste (41:54:4 in VS) improved methane production to a maximum value of 0.308 m3 CH4/kg TVSadded for an organic loading rate of 0.62-4.26 kg TVS/m3·d.


Assuntos
Reatores Biológicos , Metano , Anaerobiose , Animais , Análise da Demanda Biológica de Oxigênio , Esgotos , Suínos
20.
Curr Drug Metab ; 9(4): 336-43, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18473752

RESUMO

Capecitabine is a drug that requires the consecutive action of three enzymes: carboxylesterase 2 (CES 2), cytidine deaminase (CDD), and thymidine phosphorylase (TP) for transformation into 5-fluorouracil (5FU). The metabolism of 5FU requires the activity of thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) among other enzymes. The present study prospectively examined the possible relationship between the toxicity and efficacy of capecitabine and 14 different polymorphisms in CES 2, CDD, TS and DPD. Between 2003 and 2005, a total of 136 patients with advanced breast or colorectal cancer treated with capecitabine were prospectively enrolled. The presence of two polymorphisms (CDD 943insC and CES 2 Exon3 6046 G/A) were associated with a non-statistically significant higher incidence of grade 3 hand-foot syndrome (HFS) (p=0.07) and grade 3-4 diarrhoea (p=0.09), respectively. Patients heterozygous or homozygous for the polymorphism CES 2 5'UTR 823 C/G exhibited a significantly greater response rate to capecitabine, and time to progression of disease (59%, 8.7 months) than patients with the wild type gene sequence (32%, p=0.015; 5.3 months, p=0.014). For the first time, an association between a polymorphism in the CES2 gene and the efficacy of capecitabine has been described, providing preliminary evidence of its predictive and prognostic value.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carboxilesterase/genética , Neoplasias Colorretais/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Neoplasias da Mama/patologia , Capecitabina , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Desoxicitidina/uso terapêutico , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Progressão da Doença , Feminino , Fluoruracila/uso terapêutico , Genótipo , Humanos , Análise Multivariada , Projetos Piloto , Polimorfismo Genético/genética , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidilato Sintase/metabolismo
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