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1.
J Environ Manage ; 356: 120639, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38520857

RESUMO

Research has evolved on aerobic granular sludge (AGS) process, but still there are very few studies on the treatment of excess AGS sludge, with almost none considering its aerobic digestion. Here therefore, the aerobic digestibility of typical AGS sludge was assessed. Granules were produced from acetate-based synthetic wastewater (WW) and were subjected to aerobic digestion for 64 d. The stabilization process was monitored over time through physical-chemical parameters, oxygen uptake rates (OUR) and 16S rRNA gene sequencing. The microbial analyses revealed that the cultivated granules were dominated by slow-growing bacteria, mainly ordinary heterotrophic organisms with potential for polyhydroxyalkanoates (PHA) aerobic storage (PHA-OHOs), polyphosphate and glycogen accumulating organisms (PAOs and GAOs), fermentative anaerobes and nitrifiers (AOB and NOB). Differential abundance analysis of the bacterial data (before versus after digestion) discriminated between the most vulnerable microbiome genera and those most resistant to aerobic digestion. Furthermore, modeling of the stabilization process determined that the endogenous decay rate constant (bH) for the heterotrophs present in the granules was notably low; bH = 0.05 d-1 (average), four times less than for common activated sludge (AS), which is rated at 0.2 d-1. For first time, the research reveals another important feature of AGS sludge, i.e. the slow-decaying character of its bacteria (along with their known slow-growing character). This results in slower stabilization, need of bigger digesters and reconsideration of the specific OUR limits in biosolids regulations (SOUR limit of 1.5 mg/gTSS.h), for waste AGS compared to conventional waste AS. The study suggests that aerobic digestion of waste AGS (fully-granulated) could differ from that of conventional AS. Future work is needed on aerobic digestibility of real AGS sludges from municipal and industrial WWs, compared to synthetic WWs.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , RNA Ribossômico 16S/genética , Eliminação de Resíduos Líquidos/métodos , Genes de RNAr , Reatores Biológicos/microbiologia , Bactérias/genética , Aerobiose , Nitrogênio
2.
Artigo em Inglês | MEDLINE | ID: mdl-37531787

RESUMO

Preeclampsia (PE) is a pregnancy disorder that may be associated with inadequate maternal nutrition. Fatty acids are vital for placental and fetal growth. Fatty acid desaturases, key enzymes influencing the metabolism of polyunsaturated fatty acids, are reported to be associated with cardiometabolic risk. Any imbalance in the levels of omega-3 and omega-6 fatty acids can result in increased inflammatory response. The current study reports the levels of erythrocyte fatty acids and desaturase index across gestation in women who develop PE (n = 108) and compares them with non-PE women (n = 216). Maternal erythrocyte fatty acids were measured at 4 time points during pregnancy (i.e., 11-14, 18-22, 26-28 weeks and at delivery) using gas chromatography. Maternal total erythrocyte saturated fatty acids and omega-6/omega-3 fatty acid ratio was higher in the PE group as compared to the non-PE group at 11-14 weeks and 18-22 weeks respectively. Maternal Δ5 desaturase index was lower while Δ6 desaturase index was higher in the PE group at 11-14 and 18-22 weeks. Maternal stearoyl CoA desaturase-18 (SCD-18) index was lower at 11-14 weeks and at delivery. These changes were mainly observed in the early onset PE (EOP) group. Δ6 desaturase index at 11-14 weeks predicted the risk of EOP. Imbalance in fatty acid levels and desaturase indices predate the clinical diagnosis of PE, indicating their role in its pathophysiology. Measurement of fatty acids and desaturase indices in early pregnancy merits evaluation as predictors of risk of PE.


Assuntos
Ácidos Graxos Ômega-3 , Pré-Eclâmpsia , Feminino , Humanos , Gravidez , Ácidos Graxos/metabolismo , Pré-Eclâmpsia/metabolismo , Placenta/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Estearoil-CoA Dessaturase , Ácidos Graxos Ômega-3/metabolismo , Eritrócitos/metabolismo , Linoleoil-CoA Desaturase/metabolismo
3.
Bioresour Technol ; 384: 129346, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37336447

RESUMO

The stability of granules, contaminant removal and microbial structure of an aerobic granular sludge (AGS) process were investigated with a focus on ordinary heterotrophic organisms (OHOs). Long-term stable granules and high removals of COD (97 %), NH4+ (98 %), P (85 %) and total N (77 %) were achieved. Sequencing analyses identified 6.6 % of phosphorus-accumulating organisms in the sludge, concordant with the observed bio-P removal capacity. However, OHOs were the most abundant bacteria in the sludge (70-93 %) without resulting in unstable aggregates. Under current dogmas of microbial competition in activated sludge, it seemed contradictory that OHOs could persist in the long term in the AGS where COD was depleted beginning in the anaerobic phase. Microbial analyses showed that OHOs could survive in granules by micropredation, proteolysis, fermentation and EPS consumption. Heterotrophic-nitrification/ aerobic-denitrification was an active pathway in the AGS. These findings contribute to a better understanding of microbial competition in AGS and its stability.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos/microbiologia , Nitrogênio/metabolismo , Nitrificação , Fósforo/metabolismo , Aerobiose
4.
J Environ Manage ; 308: 114662, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35144064

RESUMO

The study investigated the mechanisms and microbial communities underlying the long-term stability and removal performances shown by aerobic granular sludge (AGS) reactor involving polyhydroxyalkanoates (PHA) aerobic-storing bacteria. The characteristics of the sludge, removal performances and bacterial community structure were determined. The prevailing metabolic phenotype was similar in the parent conventional activated sludge (CAS) reactor and its upgraded AGS version, showing high COD and NH4 uptake, versus low P and N reduction. Polyphosphate and glycogen accumulating organisms, PAO and GAO, were not enriched in the reactors despite initial targeting of anaerobic-aerobic cycle. Instead, PHA-aerobic storing bacteria (Thauera and Paracoccus) were dominant, but revealing a stable AGS system for BOD and N removal. The PAO/GAO failed selection and Thauera overgrowth were analyzed for beneficial use in developing alternative AGS technology for BOD and N removal applications.


Assuntos
Microbiota , Esgotos , Reatores Biológicos/microbiologia , Nitrogênio , Polifosfatos/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos
5.
Indian Pediatr ; 59(1): 13-20, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34480470

RESUMO

BACKGROUND: There is minimal information about the association of head growth at different stages of childhood with cognitive ability. OBJECTIVE: To determine the relationship of newborn head size and head growth during infancy, childhood and adolescence with attained education, a proxy for cognitive ability. STUDY DESIGN: Prospective birth cohort study. SETTING: Married women living in South Delhi between 1969 and 1973. PARTICIPANTS: The New Delhi Birth Cohort study followed up 8030 newborns born in 1969-1973 with head circumference, weight and height measurements at birth and 6-12 monthly until adulthood. Of these, 1526 men and women were followed up at the age of 26-32 years. OUTCOMES: Association between years of schooling, as an indicator of cognitive ability, and newborn head circumference and conditional measures of head growth during infancy, childhood and adolescence. RESULTS: In unadjusted analyses, newborn head size was positively associated with years of education [(b (95% CI)=0.30 (0.14 to 0.47) years per SD head circumference], as was head growth from birth to 6 months [b (95% CI)=0.44 (0.28 to 0.60) years per SD conditional head growth], 6 months to 2 years [b (95% CI)=0.31 (0.15 to 0.47) years per SD conditional head growth] and 2 to 11 years [b (95% CI)=0.20 (0.03 to 0.36) years per SD conditional head growth]. There were similar findings for height and body mass index (BMI). In the adjusted model containing all growth measures, gestational age, and socio-economic status (SES) at birth as predictors, only SES was positively associated with educational attainment. CONCLUSION: Educational attainment in this population is positively associated with socioeconomic status and its influence on inter-related early life (fetal, infant and childhood) factors like nutritional status and brain growth.


Assuntos
Estatura , Adolescente , Adulto , Peso ao Nascer , Índice de Massa Corporal , Estudos de Coortes , Escolaridade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
J Environ Health Sci Eng ; 18(2): 755-768, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33312600

RESUMO

BACKGROUND: In developing countries, death due to diseases caused by fecal-oral ingestion can be avoided by taking action on drinking water issues. Adequate access to water treatment systems to reduce infections is a critical cause. Silver has been used as an antibacterial product, including biomedical applications. Therefore, in this paper, the effect of the chemical speciation of silver from silver-modified zeolite-rich tuffs on the mortality of Escherichia coli (E. coli), Streptococcus faecalis (S. faecalis) and Candida albicans (C. albicans) suspended in aqueous solution was investigated for disinfection purposes. METHODS: The following aspects were considered to develop the investigation: a) the technique to prepare the modified zeolitic materials, either with ionic silver or silver nanoparticles, which were obtained in two ways: one, with grapefruit extract and the second, by using non-thermal plasma generated in a dielectric barrier discharge reactor of parallel plates; b) the response of the prokaryotes (bacteria) and eukaryote (yeast) microorganisms to disinfectant agents in batch systems; c) the disinfection processes as a function of time to obtain kinetics parameters; and d) the kinetics of the silver release from the silver-modified zeolite-rich tuffs, considering the models of Higuchi and Korsmeyer. The zeolitic materials were characterized by low-vacuum scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). RESULTS: The non-thermal plasma reduced ionic silver is more efficient at generating silver compounds with several oxidation states, which are essential during the microbial inhibition process. For the bacterial (E. coli and S. faecalis), the materials with nanoparticles were efficient to inactivate them. However, the yeast (C. albicans) reaches the total inactivation when the zeolitic material contains ionic silver in the crystalline network. CONCLUSION: The E. coli, S. faecalis and C. albicans survival behavior suspended in aqueous solutions after contact with Ag-modified natural zeolites depends on the chemical speciation of the silver present in these materials, Ag+1 in the case of OAgiZ or nanoparticles of Ago promoted by the grapefruit extract (OAgnpTZ), as well as by non-thermal plasma generated in a dielectric barrier discharge reactor of parallel plates (OAgnpPZ). In general, the concentration of silver in the aqueous solution after the disinfection process cannot exceed the recommended levels established for international organizations. The OAgnpPZ is a potential microbicide agent against E. coli and C. albicans, and the OAgn pTZ for F. faecalis.Graphical abstractARTWORK.

7.
Water Sci Technol ; 79(12): 2251-2259, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31411579

RESUMO

The objective of the present study was to determine the optimum operating temperature of laboratory-scale upflow anaerobic sludge blanket (UASB) reactors during the treatment of a chocolate-processing industry wastewater at medium applied organic loading rates (OLRappl). Four UASB reactors were operated at different temperature (15, 20, 25 and 30 °C) and three OLRappl (2, 4 and 6 kg soluble chemical oxygen demand (CODs)/(m3 d)). The flowrate and the hydraulic retention time were constant (11.5 L/d and 6 h, respectively). The monitored parameters were pH, temperature, CODs, and total and volatile suspended solids. The CODs removal efficiency (RE) and biogas production rate (BPR) were calculated. The 15 °C UASB reactor had the lowest RE (39 to 78%) due to the low operating temperature. Regardless of the OLRappl, the RE of the 20, 25 and 30 °C reactors was high and similar to each other (between 88 and 94%). The BPR of the four UASB reactors had the same behaviour as the RE (BPR of 15 °C: 0.3 to 0.5 Lbiogas/(Lreactor d) (Lb/(Lr d)) and BPR of 20, 25 and 30 °C: 0.5 to 1.9 Lb/(Lr d)).


Assuntos
Chocolate , Eliminação de Resíduos Líquidos , Águas Residuárias , Anaerobiose , Reatores Biológicos , Esgotos , Temperatura
8.
Indian Pediatr ; 55(2): 125-130, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29242410

RESUMO

OBJECTIVE: We examined associations of different adiposity measures with cortisol responses during the Trier Social Stress Test for children (TSST-C). DESIGN: Descriptive study. SETTING: Holdsworth Memorial Hospital, Mysore, India. PARTICIPANTS: Adolescents aged 13.5y from a birth cohort were recruited (N=269, 133 boys). METHODS: The stressor (TSST-C) was 5-minutes each of public speaking and mental arithmetic tasks in front of two unfamiliar 'judges'. Salivary cortisol concentrations were measured at baseline and at regular intervals after TSST-C. Weight, height, sub scapular and triceps skinfold thickness, and waist and hip circumference were measured, and percentage body fat was estimated (fat%; bioimpedance). Body mass index (BMI) and Waist-to-hip ratio (WHR) were calculated. All variables were converted into within-cohort SD scores before analysis. Stress-induced change in cortisol concentrations from baseline (cortisol response) was examined in relation to adiposity. RESULTS: Stress increased cortisol concentrations significantly from baseline (mean (SD): 5.5 (6.4) ng/mL; P<0.001). Higher WHR was associated with lower cortisol response at 20 and 30-minutes after stress (~0.13 SD decrease in cortisol response per SD higher WHR, P<0.05). Higher fat% was also associated with lower cortisol response only in girls 20-minutes post-stress (0.23 SD lower response per SD higher fat%, P=0.004). Sum of skinfold thickness and BMI were not associated with cortisol responses. CONCLUSION: Abdominal adiposity is associated with reduced hypothalamic-pituitary-adrenal axis reactivity to stress in this adolescent population.


Assuntos
Adiposidade/fisiologia , Hidrocortisona/análise , Estresse Psicológico/epidemiologia , Estresse Psicológico/fisiopatologia , Adolescente , Índice de Massa Corporal , Feminino , Humanos , Sistema Hipotálamo-Hipofisário , Índia/epidemiologia , Masculino , Sistema Hipófise-Suprarrenal , Testes Psicológicos , Saliva/química
9.
J Environ Manage ; 206: 103-112, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29059565

RESUMO

Applying ozone to the return flow in an activated sludge (AS) process is a way for reducing the residual solids production. To be able to extend the activated sludge models to the ozone-AS process, adequate prediction of the tri-atoms effects on the particulate COD fractions is needed. In this study, the biomass inactivation, COD mineralization, and solids dissolution were quantified in batch tests and dose-response models were developed as a function of the reacted ozone doses (ROD). Three kinds of model-sludge were used. S1 was a lab-cultivated synthetic sludge with two components (heterotrophs XH and XP). S2 was a digestate of S1 almost made by the endogenous residues, XP. S3 was from a municipal activated sludge plant. The specific ozone uptake rate (SO3UR, mgO3/gCOD.h) was determined as a tool for characterizing the reactivity of the sludges. SO3UR increased with the XH fraction and decreased with more XP. Biomass inactivation was exponential (e-ß.ROD) as a function of the ROD doses. The percentage of solids reduction was predictable through a linear model (CMiner + Ysol ROD), with a fixed part due to mineralization (CMiner) and a variable part from the solubilization process. The parameters of the models, i.e. the inactivation and the dissolution yields (ß, 0.008-0.029 (mgO3/mgCODini)-1 vs Ysol, 0.5-2.8 mg CODsol/mgO3) varied in magnitude, depending on the intensity of the scavenging reactions and potentially the compactness of the flocs for each sludge.


Assuntos
Ozônio , Esgotos , Biomassa , Eliminação de Resíduos Líquidos
10.
Int J Obes (Lond) ; 42(4): 850-857, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29151596

RESUMO

BACKGROUND/OBJECTIVES: Fat distribution is a strong and independent predictor of type 2 diabetes (T2D) and cardiovascular disease (CVD) and is usually determined using conventional anthropometry in epidemiological studies. Dual-energy X-ray absorptiometry (DXA) can measure total and regional adiposity more accurately. Nonetheless, whether DXA provides more precise estimates of cardiovascular risk in relation to total and regional adiposity is not known. We determined the strength of the associations between DXA- and conventional anthropometry determined fat distribution and T2D and CVD risk markers. SUBJECTS/METHODS: Waist (WC) and hip circumference (HC) and DXA was used to measure total and regional adiposity in 4950 (2119 men) participants aged 29-55 years from the Oxford Biobank without pre-existing T2D or CVD. Cross-sectional associations were compared between WC and HC vs. DXA-determined regional adiposity (all z-score normalised) with impaired fasting glucose, hypertriglyceridemia, hypertension and insulin resistance (IR). RESULTS: Following adjustment for total adiposity, upper body adiposity measurements showed consistently increased risk of T2D and CVD risk markers except for abdominal subcutaneous fat in both sexes, and arm fat in men, which showed protective associations. Among upper adiposity depots, visceral fat mass showed stronger odds ratios (OR) ranging from 1.69 to 3.64 compared with WC 1.07-1.83. Among lower adiposity depots, HC showed modest protection for IR in both sexes (men: OR 0.80 (95% confidence interval 0.67, 0.96); women: 0.69 (0.56, 0.86)), whereas gynoid fat and in particular leg fat showed consistent and strong protective effects for all outcomes in both men and women. The differential effect of body fat distribution on CVD and T2D were more pronounced at higher levels of total adiposity. CONCLUSIONS: Compared with DXA, conventional anthropometry underestimates the associations of regional adiposity with T2D and CVD risk markers. After correcting for overall adiposity, greater subcutaneous fat mass in particular in the lower body is protective relative to greater android or visceral adipose tissue mass.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Tamanho Corporal/fisiologia , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Absorciometria de Fóton , Adulto , Antropometria , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
Chemosphere ; 189: 357-364, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28946069

RESUMO

Ozonation of the return activated sludge (AS) flow is an emerging option for excess-sludge reduction. This study aimed to evaluate the potential changes suffered by some kinetic parameters of the activated sludge models (ASMs) in the combined ozone-AS process. The heterotrophic maximum specific growth rate (µHmax) was determined by respirometry in three model-sludges (S1 to S3) treated in batch with different O3 doses. S1 was a fresh synthetic biosolid composed by only two particulate fractions. S2 was a digestate of S1 almost made by the endogenous residues. S3 was from a municipal wastewater treatment plant. µHmax increased significantly from 3.5 d-1 originally, to more than 10 d-1 in the ozonated sludges. Ozonation promoted the selection of fast-growing bacteria in the activated sludges, after transitory inactivation and long lag times. Some microorganisms survived to 3 months of digestion and subsequent ozonation, and then regrow faster than before, once fed again with acetate. The research is of interest from the point of view of the application of the ASM models to the ozone-AS process, but also for wastewater disinfection in general.


Assuntos
Ozônio/química , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Bactérias , Esgotos/química , Águas Residuárias/química
12.
Int Sch Res Notices ; 2016: 7294274, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27774509

RESUMO

Primary hyperparathyroidism (PHPT) is rarely associated with the occurrence of acute or chronic pancreatitis. Hypercalcemia plays a major role in the pathogenesis. We report five cases of pancreatitis revealing PHPT. Patients and Methods. This is a retrospective study of 4 years, including all patients admitted to intensive care unit or gastroenterology department, for an acute or chronic pancreatitis revealing primary hyperparathyroidism. Results. We included 5 patients, all female, with mean age 54 years [40-76 years]. The PHPT was in all cases revealed by acute pancreatitis (AP). This one was oedematous in four cases and severe in one case. It occurred twice in calcified chronic pancreatitis (CCP). There was hypercalcemia in all cases. The PHPT was associated with a high rate of parathyroid hormone in 4 cases. The secreting lesion was an adenoma in 5 cases. Two patients had in addition bilateral renal calcifications. The outcome was favorable in 4 patients among whom 3 have had parathyroid surgery. A death was noted by superinfection of necrosis in the case of severe AP. Conclusion. The occurrence of pancreatitis during hyperparathyroidism is rare. Normal or elevated calcemia during acute or chronic pancreatitis should always get attention.

14.
Bioresour Technol ; 203: 32-41, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26720137

RESUMO

This study was performed to identify suitable conditions for the in-situ reduction of excess sludge production by intercalated digesters in recycle-activated sludge (RAS) flow. The objective was to compare and model biological sludge mass reduction and the biodegradation of endogenous residues (XP) by digestion under hypoxic, aerobic, anaerobic, and five intermittent-aeration conditions. A mathematical model based on the heterotrophic endogenous decay constant (bH) and including the biodegradation of XP was used to fit the long-term data from the digesters to identify and estimate the parameters. Both the bH constant (0.02-0.05 d(-1)) and the endogenous residue biodegradation constant (bP, 0.001-0.004 d(-1)) were determined across the different mediums. The digesters with intermittent aeration cycles of 12 h-12 h and 5 min-3 h (ON/OFF) were the fastest, compared to the aerobic reactor. The study provides a basis for rating RAS-digester volumes to avoid the accumulation of XP in aeration tanks.


Assuntos
Reatores Biológicos , Modelos Biológicos , Esgotos , Gerenciamento de Resíduos/métodos , Aerobiose , Anaerobiose , Biodegradação Ambiental , Reciclagem
15.
J Theor Biol ; 388: 37-49, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26497917

RESUMO

Most cancer treatments efficacy depends on tumor metastasis suppression, where tumor suppressor genes play an important role. Maspin (Mammary Serine Protease Inhibitor), an non-inhibitory serpin has been reported as a potential tumor suppressor to influence cell migration, adhesion, proliferation and apoptosis in in vitro and in vivo experiments in last two decades. Lack of computational investigations hinders its ability to go through clinical trials. Previously, we reported first computational model for maspin effects on tumor growth using artificial neural network and cellular automata paradigm with in vitro data support. This paper extends the previous in silico model by encompassing how maspin influences cell migration and the cell-extracellular matrix interaction in subcellular level. A feedforward neural network was used to define each cell behavior (proliferation, quiescence, apoptosis) which followed a cell-cycle algorithm to show the microenvironment impacts over tumor growth. Furthermore, the model concentrates how the in silico experiments results can further confirm the fact that maspin reduces cell migration using specific in vitro data verification method. The data collected from in vitro and in silico experiments formulates an unsupervised learning problem which can be solved by using different clustering algorithms. A density based clustering technique was developed to measure the similarity between two datasets based on the number of links between instances. Our proposed clustering algorithm first finds the nearest neighbors of each instance, and then redefines the similarity between pairs of instances in terms of how many nearest neighbors share the two instances. The number of links between two instances is defined as the number of common neighbors they have. The results showed significant resemblances with in vitro experimental data. The results also offer a new insight into the dynamics of maspin and establish as a metastasis suppressor gene for further molecular research.


Assuntos
Simulação por Computador , Modelos Biológicos , Neoplasias/metabolismo , Serpinas/metabolismo , Algoritmos , Apoptose , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Matriz Extracelular/metabolismo , Humanos , Metástase Neoplásica , Neoplasias/patologia , Ligação Proteica , Mapas de Interação de Proteínas , Transdução de Sinais , Microambiente Tumoral
16.
Environ Technol ; 37(5): 558-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26362939

RESUMO

The adsorption of fluoride and arsenic ions by modified natural materials may have an impact on the removal of F- and As(V) from waters. In this work, a zeolitic material and pozzolan (commonly known as pumicite) were modified with aluminium an iron by an electrochemical method and chemical precipitation, respectively. The adsorbents were characterized by X-ray diffraction, scanning electron microscopy with energy X-ray disperse spectroscopy analysis and the point of zero charge (pHzpc). F- and As(V) adsorption properties of both materials were investigated. Adsorption kinetic data were best fitted to pseudo-second-order model and equilibrium data to the Langmuir isotherm model. The highest F- and As(V) sorption capacities were obtained for modified zeolitic (0.866 mg/g) and pozzolan (3.35 mg/g) materials, respectively, with initial F- or As(V) concentrations of 10 mg/L. It was found that the unmodified materials did not show either adsorption of F- ions or As(V), which indicated that Al and Fe in the adsorbents are responsible for the adsorption of these ions. In general, both modified materials show similar capacities for the adsorption of F- and As(V).


Assuntos
Alumínio/química , Arsênio/química , Técnicas Eletroquímicas , Fluoretos/química , Ferro/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Precipitação Química
18.
J Epidemiol Community Health ; 69(12): 1147-53, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26186243

RESUMO

BACKGROUND: Indian babies are characterised by the 'thin-fat phenotype' which comprises a 'muscle-thin but adipose' body composition compared with European babies. This body phenotype is of concern because it is associated with an increased risk of diabetes and cardiovascular disease. We examined whether the 'thin-fat phenotype' persists through early childhood, comparing Indian children with white Caucasians in the UK at birth, infancy and childhood, using comparable measurement protocols. METHODS: We used data from two cohorts, the Pune Maternal Nutrition Study (N=631) and the Southampton Women's Survey (N=2643). Measurements of weight, head circumference, mid-upper arm circumference, height, triceps and subscapular skinfold thickness were compared at birth, 1, 2, 3 and 6 years of age. SD scores were generated for the Pune children, using the Southampton children as a reference. Generalised estimating equations were used to examine the changes in SD scores across the children's ages. RESULTS: The Indian children were smaller at birth in all body measurements than the Southampton children and became relatively even smaller from birth to 2 years, before 'catching up' to some extent at 3 years, and more so by 6 years. The deficit for both skinfolds was markedly less than for other measurements at all ages; triceps skinfold showed the least difference between the two cohorts at birth, and subscapular skinfold at all ages after birth. CONCLUSIONS: The 'thin-fat phenotype' previously found in Indian newborns, remains through infancy and early childhood. Despite being shorter and lighter than UK children, Indian children are relatively adipose.


Assuntos
Composição Corporal/genética , Tamanho Corporal/genética , Dobras Cutâneas , Adulto , Aleitamento Materno/estatística & dados numéricos , Criança , Pré-Escolar , Inglaterra , Feminino , Humanos , Índia , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Idade Materna , Mães/estatística & dados numéricos , Fenótipo , Adulto Jovem
19.
Eur J Clin Microbiol Infect Dis ; 34(5): 927-33, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25575949

RESUMO

Recent research on Staphylococcus aureus vaccine development has focused on active immunization against Panton-Valentine leukocidin (PVL), a potent leukotoxin associated with both superficial and severe deep-seated infections. PVL prevalence is highly variable worldwide, but it is unknown to what extent immunity to PVL varies between patients from geographic areas with different PVL-positive S. aureus prevalences. We conducted a retrospective multicentric study of anti-PVL and anti-alpha-toxin (Hla) antibody levels in uninfected adult patients from France (low PVL prevalence; n = 200), Algeria (moderate prevalence; n = 143), and Senegal (high prevalence; n = 228). The antibody levels were quantified by an enzyme-linked immunosorbent assay (ELISA) procedure. Because Hla is present in virtually all S. aureus strains, its corresponding antibody levels were considered to reflect population exposure to S. aureus. Compared with French participants, the average anti-PVL antibody levels were 2.5-fold and 8.2-fold higher in Algerian and Senegalese participants, respectively (p < 0.001). Conversely, anti-Hla antibody levels did not differ between participants from the three countries, suggesting that the observed differences in anti-PVL antibody levels were not biased by variations in population exposure to S. aureus. Hence, anti-PVL antibody levels in the general populations of France, Algeria, and Senegal vary widely and match variations in PVL-positive S. aureus strain prevalence, with an increasing north-to-south gradient. To conclude, immunity to PVL in a given population correlates with local PVL prevalence. This finding can help to inform PVL vaccine strategies.


Assuntos
Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/imunologia , Exotoxinas/imunologia , Leucocidinas/imunologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/imunologia , Adulto , Idoso , Argélia/epidemiologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , França/epidemiologia , Geografia , Proteínas Hemolisinas/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Senegal/epidemiologia , Estudos Soroepidemiológicos
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 4399-402, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26737270

RESUMO

Assistive Technologies (ATs) also called extrinsic enablers are useful tools for people living with various disabilities. The key points when designing such useful devices not only concern their intended goal, but also the most suitable human-machine interface (HMI) that should be provided to users. This paper describes the design of a highly intuitive wireless controller for people living with upper body disabilities with a residual or complete control of their neck and their shoulders. Tested with JACO, a six-degree-of-freedom (6-DOF) assistive robotic arm with 3 flexible fingers on its end-effector, the system described in this article is made of low-cost commercial off-the-shelf components and allows a full emulation of JACO's standard controller, a 3 axis joystick with 7 user buttons. To do so, three nine-degree-of-freedom (9-DOF) inertial measurement units (IMUs) are connected to a microcontroller and help measuring the user's head and shoulders position, using a complementary filter approach. The results are then transmitted to a base-station via a 2.4-GHz low-power wireless transceiver and interpreted by the control algorithm running on a PC host. A dedicated software interface allows the user to quickly calibrate the controller, and translates the information into suitable commands for JACO. The proposed controller is thoroughly described, from the electronic design to implemented algorithms and user interfaces. Its performance and future improvements are discussed as well.


Assuntos
Pessoas com Deficiência , Algoritmos , Braço , Humanos , Procedimentos Cirúrgicos Robóticos , Tecnologia Assistiva , Interface Usuário-Computador , Tecnologia sem Fio
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