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1.
J Environ Manage ; 140: 45-50, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24726964

ABSTRACT

The efficient reuse of industrial by-products, such as the electric arc furnace (EAF) black slag, is still hindered by concern over their long-term behaviour in outdoor environments. The aim of this study was to develop an accelerated ageing method to simulate the long-term natural carbonation of EAF slag exposed to the elements. The degree of carbonation achieved in a freshly produced slag after accelerated ageing and in a slag used on a fifteen-year-old unpaved road was very similar. The influence of particle size on accelerated carbonation was assessed, with it being concluded that the slag sample with a particle size bigger than 5-6 mm underwent slight carbonation over time when it was exposed to CO2. The accelerated ageing procedure based on percolating a previously carbonated water solution through the slag column allowed gradual leaching with simulated acid rain, as well as providing information about the gradual and total chemical release from the slag. Three classification groups were established according to the release rate of the determined elements. The joint use of the accelerated carbonation method and the percolation test is proposed as a useful tool for environmental risk assessment concerning the long-term air exposure of EAF black slag.


Subject(s)
Carbonates/chemistry , Industrial Waste , Steel , Carbon Dioxide/chemistry , Particle Size , Risk Assessment
2.
J Air Waste Manag Assoc ; 64(12): 1403-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25562936

ABSTRACT

Bioprocesses, such as biofiltration, are commonly used to treat industrial effluents containing volatile organic compounds (VOCs) at low concentrations. Nevertheless, the use of biofiltration for indoor air pollution (IAP) treatment requires adjustments depending on specific indoor environments. Therefore, this study focuses on the convenience of a hybrid biological process for IAP treatment. A biofiltration reactor using a green waste compost was combined with an adsorption column filled with activated carbon (AC). This system treated a toluene-micropolluted effluent (concentration between 17 and 52 µg/m3), exhibiting concentration peaks close to 733 µg/m3 for a few hours per day. High removal efficiency was obtained despite changes in toluene inlet load (from 4.2 x 10(-3) to 0.20 g/m3/hr), which proves the hybrid system's effectiveness. In fact, during unexpected concentration changes, the efficiency of the biofilter is greatly decreased, but the adsorption column maintains the high efficiency of the entire process (removal efficiency [RE] close to 100%). Moreover, the adsorption column after biofiltration is able to deal with the problem of the emission of particles and/or microorganisms from the biofilter. Implications: Indoor air pollution is nowadays recognized as major environmental and health issue. This original study investigates the performance of a hybrid biological process combining a biofilter and an adsorption column for removal of indoor VOCs, specifically toluene.


Subject(s)
Air Pollutants/metabolism , Air Pollution, Indoor/prevention & control , Environmental Restoration and Remediation/methods , Toluene/metabolism , Adsorption , Biodegradation, Environmental , Bioreactors , Charcoal/metabolism , Filtration
3.
An. pediatr. (2003, Ed. impr.) ; 78(4): 268-268[e1-e7], abr. 2013. tab, graf
Article in Spanish | IBECS | ID: ibc-110396

ABSTRACT

En España, hasta el año 2010 se ha prestado poca atención a los adolescentes con cáncer. En el año 2011 se crea el Comité de adolescentes con cáncer dentro de la Sociedad Española de Onco-Hematología Pediátrica (SEHOP), con el objetivo de cubrir las demandas y necesidades de estos pacientes. Con esta encuesta nacional se pretende obtener una fotografía de la situación actual de los adolescentes con cáncer en las unidades de hemato-oncología pediátrica españolas. Se ha realizado una encuesta, enviada vía email a 41 unidades de hemato-oncología pediátrica españolas. Se incluyen preguntas acerca de la epidemiología, el tratamiento, el abordaje psicosocial, las instalaciones y el seguimiento de estos pacientes. Un total de 40 unidades respondieron a la encuesta (98%). El 56% de las unidades trata a pacientes por encima de los 14 años, pero solo el 36% hasta los 18 años. Solo el 25,5% de las unidades trata más de 40 casos nuevos cada año. El porcentaje de los pacientes entre 14 y 18 años del total es menor del 10% en la mayoría de las unidades (77%).El 30,8 y el 48,7% de las unidades pediátricas tratan los adolescentes con hemopatías malignas y con tumores sólidos, respectivamente. El resto de los adolescentes con estas afecciones son tratados por los servicios de adultos. Solo existe una unidad en España que tenga un médico dedicado a la enfermedad oncológica del adolescente y solo hay 2 unidades que tengan una sala específica para adolescentes. Esta encuesta demuestra que la mayoría de los adolescentes con cáncer en España son tratados por especialistas de adultos, a pesar de que la supervivencia de estos pacientes es mayor cuando se utilizan protocolos pediátricos para su tratamiento. La mayoría de las unidades no tienen instalaciones ni personal especialmente dedicados a este grupo de pacientes. La SEHOP está aunando esfuerzos para mejorar tanto la supervivencia como la calidad del tratamiento de estos pacientes(AU)


Little attention was paid to adolescents with Cancer in Spain up to 2010. In 2011 an “Adolescents with Cancer Committee” was established by the Spanish Society of Pediatric Hemato-Oncology (SEHOP) to care for the needs of these patients. The aim of this national survey was to outline the present situation of adolescents with cancer in Spanish Pediatric Hemato-Oncology units. A web based survey assessed institutional management of adolescents with cancer. The survey was personally sent to one member of the staff of each Pediatric Hemato-Oncology unit in Spain. It included questions about epidemiology, management, psycho-social coverage, specific facilities, and follow up of these patients. A total of 40 institutions out of 41 responded to the survey (overall response rate 98%). Fifty-six percent of the institutions had patients over 14, but only 36% of the institutions treated patients up to 18 years old. Only 25.6% of the units have more than 40 new pediatric cases every year. The percentage of patients between 14 and 18 years of age is below 10% in most of the units (77%).The survey shows that most adolescents with cancer in Spain between 14 and 18 years of age are treated by adult oncologists. Most pediatric institutions still do not have specific facilities and psychosocial support for adolescents. The SEHOP is working hard in order to improve the quality of cancer care, and the quality of survival of this population. In 30.8% and 48.7% of the institutions, pediatric hemato-oncologists treat adolescents with hematological and solid tumors, respectively. The rest of the patients are seen by adult oncologists. There is only one institution that has a physician specifically dedicated to adolescent patients, and only two units have a “teenager's room”. Only 2 units have a psychologist specifically trained to treat adolescents with cancer(AU)


Subject(s)
Humans , Male , Female , Adolescent , Neoplasms/epidemiology , Oncology Service, Hospital/statistics & numerical data , 24419 , Survival Rate
4.
An Pediatr (Barc) ; 78(4): 268.e1-7, 2013 Apr.
Article in Spanish | MEDLINE | ID: mdl-23201346

ABSTRACT

Little attention was paid to adolescents with Cancer in Spain up to 2010. In 2011 an "Adolescents with Cancer Committee" was established by the Spanish Society of Pediatric Hemato-Oncology (SEHOP) to care for the needs of these patients. The aim of this national survey was to outline the present situation of adolescents with cancer in Spanish Pediatric Hemato-Oncology units. A web based survey assessed institutional management of adolescents with cancer. The survey was personally sent to one member of the staff of each Pediatric Hemato-Oncology unit in Spain. It included questions about epidemiology, management, psycho-social coverage, specific facilities, and follow up of these patients. A total of 40 institutions out of 41 responded to the survey (overall response rate 98%). Fifty-six percent of the institutions had patients over 14, but only 36% of the institutions treated patients up to 18 years old. Only 25.6% of the units have more than 40 new pediatric cases every year. The percentage of patients between 14 and 18 years of age is below 10% in most of the units (77%). In 30.8% and 48.7% of the institutions, pediatric hemato-oncologists treat adolescents with hematological and solid tumors, respectively. The rest of the patients are seen by adult oncologists. There is only one institution that has a physician specifically dedicated to adolescent patients, and only two units have a "teenager's room". Only 2 units have a psychologist specifically trained to treat adolescents with cancer. The survey shows that most adolescents with cancer in Spain between 14 and 18 years of age are treated by adult oncologists. Most pediatric institutions still do not have specific facilities and psychosocial support for adolescents. The SEHOP is working hard in order to improve the quality of cancer care, and the quality of survival of this population.


Subject(s)
Neoplasms/epidemiology , Adolescent , Health Care Surveys , Hematology , Hospital Units , Humans , Medical Oncology , Pediatrics , Spain , Surveys and Questionnaires
5.
J Hazard Mater ; 185(2-3): 1019-26, 2011 Jan 30.
Article in English | MEDLINE | ID: mdl-21030149

ABSTRACT

The influence of water irrigation on both the long-term and short-term performance of p-xylene biodegradation under several organic loading scenarios was investigated using an organic packing material composed of pelletised sawdust and pig manure. Process operation in a modular biofilter, using no external water supply other than the moisture from the saturated inlet air stream, showed poor p-xylene abatement efficiencies (≈33 ± 7%), while sustained irrigation every 25 days rendered a high removal efficiency (RE) for a critical loading rate of 120 g m(-3)h(-1). Periodic profiles of removal efficiency, temperature and moisture content were recorded throughout the biofilter column subsequent to each biofilter irrigation. Hence, higher p-xylene biodegradation rates were always initially recorded in the upper module, which resulted in a subsequent increase in temperature and a decrease in moisture content. This decrease in the moisture content in the upper module resulted in a higher removal rate in the middle module, while the moisture level in the lower module steadily increased as a result of water condensation. Based on these results, mass balance calculations performed using measured bed temperatures and relatively humidity values were successfully used to account for water balances in the biofilter over time. Finally, the absence of bed compaction after 550 days of continuous operation confirmed the suitability of this organic material for biofiltration processes.


Subject(s)
Biodegradation, Environmental , Filtration/instrumentation , Water Pollutants, Chemical/metabolism , Xylenes/metabolism , Animals , Manure , Swine
6.
Colorectal Dis ; 12(4): 342-50, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19207698

ABSTRACT

OBJECTIVE: Restorative proctectomy with straight coloanal anastomosis (CAA) and restorative proctocolectomy with ilealpouch-anal anastomosis (IPAA) are options for maintaining bowel integrity after rectal resection. The aim of this study was to compare clinical function and anorectal physiology in patients treated with CAA and IPAA. METHOD: Three-dimensional vector-manometry and neorectal volumetry were performed in straight CAA [53 patients (34 male)] and IPAA [61 patients (39 male)] for ulcerative colitis. Function was assessed using a 14 day incontinence diary. RESULTS: Function was similar in both groups, but neorectal compliance and threshold volumes for sensation, urge and maximum tolerated volume (MTV) were significantly higher after IPAA than after CAA. Mean pressure, vector volume and sphincter symmetry at rest were significant determinants of continence in both groups but squeeze pressure did not correlate significantly with function in either group. Threshold volume, MTV, and compliance were significantly correlated with frequency of defecation in patients with IPAA but not with CAA. CONCLUSION: A strong consistent resting anal sphincter pressure is one determinant of continence after both IPAA and CAA. Squeeze pressures do not influence the functional result. In IPAA but not CAA, the neorectum has a reservoir function which correlates with the postoperative frequency of defaecation.


Subject(s)
Anal Canal/physiology , Defecation/physiology , Proctocolectomy, Restorative/methods , Recovery of Function , Rectum/physiology , Aged , Aged, 80 and over , Colitis, Ulcerative/surgery , Fecal Incontinence/etiology , Follow-Up Studies , Humans , Male , Manometry , Middle Aged , Proctocolectomy, Restorative/adverse effects
7.
J Hazard Mater ; 151(1): 78-85, 2008 Feb 28.
Article in English | MEDLINE | ID: mdl-17600620

ABSTRACT

Although total metal content is frequently the initial approach for measuring pollution, no information is provided about mobility and environmental risk. In this paper, a metal fractionation (sequential extraction) technique and artificial neural networks (Self-Organizing Maps, SOMs) have been used jointly to evaluate the pollution level of the sediments dredged from the dry dock of a former shipyard in the Bilbao estuary (Bizkaia, Spain). The load pollution index (LPI) for the upper, middle and bottom layers of the sediments was 7.65, 8.22 and 10.01, respectively, for six metals (Cu, Mn, Ni, Cr, Pb and Zn). This showed that upper sediments were less polluted than the lower ones. Consequently, a reduction in the pollution level of metal discharged into the river in recent years was confirmed. According to fractionation results, the most mobile minor elements were Cu, Pb and Zn, as they are mainly associated with the non-residual fractions. The statistical approach of Self-Organizing Maps (SOMs) revealed that Ni, Pb and Zn amounts in the residual fraction followed the same pattern associated with simultaneous discharges of slags into the river. However, other hazardous discharge sources are responsible for the high accumulation of those metals in the non-residual fractions.


Subject(s)
Environmental Pollutants/analysis , Geologic Sediments/analysis , Metals/analysis , Neural Networks, Computer
8.
Bioprocess Biosyst Eng ; 29(2): 129-36, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16770593

ABSTRACT

Based on an experimental database consisting of 194 daily cases, artificial neural networks were used to model the removal efficiency of a biofilter for treating hydrogen sulphide (H2S). In this work, the removal efficiency of the reactor was considered as a function of the changes in the air flow and concentration of H2S entering the biofilter. In order to obtain true representative values, the removal efficiencies (outputs) were measured 24 h after each input was changed. A MLP (multilayer perceptron 2-2-1) model with two input variables (unit flow and concentration of the contaminant fed into the biofilter) rendered good prediction values with a determination coefficient of 0.92 for the removal efficiency within the range studied. This means that the MLP model can explain 92% of the overall variability detected in the biofilter corresponding to a wide range of operating conditions.


Subject(s)
Air Pollutants/metabolism , Hydrogen Sulfide/metabolism , Models, Biological , Neural Networks, Computer , Waste Management/methods
9.
Environ Pollut ; 113(1): 79-85, 2001.
Article in English | MEDLINE | ID: mdl-11351764

ABSTRACT

The distribution of Pb, Ni and Zn in two contaminated soils was determined before and after treating the soils with an EDTA solution. After the EDTA extraction, the proportion of Pb accumulated in the acid-extractable fraction considerably increased, which was related to the greater degree of metal extraction from the other fractions. EDTA was also able to extract certain amounts of Pb, Zn and Ni from the silicate matrix, which implied that these extractable amounts were not so strongly fixed to the residual fraction as previously supposed. As a consequence, after EDTA application, metal content (especially Pb) remained more weakly adsorbed to soil components (more easily leachable), potentially favouring the application of phytoremediation technologies. The extraction recoveries (for only one application) were generally low for the three metals (33-37% for Pb, 5-11% for Ni and 14-19% for Zn), although this fact is an advantage as plants would not be able to assimilate very high mobilised contents of metals.


Subject(s)
Chelating Agents , Decontamination , Edetic Acid , Environmental Monitoring , Metals, Heavy/analysis , Soil Pollutants/analysis , Decontamination/methods , Environmental Monitoring/methods , Humans , Metals, Heavy/chemistry
10.
Health Policy Plan ; 16 Suppl 2: 44-51, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11772989

ABSTRACT

BACKGROUND: In 1993, Colombia enacted and subsequently implemented a radical reform in its system of providing health care for the poor, moving in a short time from a traditional model of providing health services in public hospitals to a managed competition model in which the government buys health insurance for the poor. This study examines and attempts to draw lessons from the early experience with this reform. METHODS: Information was gathered from document reviews and interviews with key actors at both the national and local levels. Other quantitative data, such as data from existing national surveys and financial operating data, were also used as available. RESULTS: The new system made important achievements in its first few years, including the enrollment of 7 million Colombians (about half of the targeted population) in health insurance plans and improving access to care. Nevertheless, there were substantial problems with the lack of managerial infrastructure and flow of information needed for the new system to function properly. Because of these difficulties, substantial resources were wasted, and insurance coverage did not always result in true access to health care. CONCLUSIONS: Other countries contemplating similar reforms should educate health administrators and the public, and establish solid administrative capacity in advance of implementation. In Colombia, many initial problems still need to be overcome while maintaining and extending the programme's important accomplishments.


Subject(s)
Developing Countries , Health Care Reform , Health Plan Implementation , Health Services Accessibility/legislation & jurisprudence , Managed Competition/legislation & jurisprudence , Colombia , Efficiency, Organizational , Health Services Research , Humans , Models, Organizational , National Health Programs/legislation & jurisprudence , National Health Programs/organization & administration , Poverty , Public Health Administration
11.
Biodegradation ; 11(6): 423-7, 2000.
Article in English | MEDLINE | ID: mdl-11587447

ABSTRACT

A laboratory scale bioreactor has been designed and set up in order to degrade hydrogen sulfide from an air stream. The reactor is a vertical column of 7 litre capacity and 1 meter in height. It is divided into three modules and each module is filled with pellets of agricultural residues as packing bed material. The gas stream fed into the reactor through the upper inlet consists of a mixture of hydrogen sulfide and humidified air. The hydrogen sulfide content in the inlet gas stream was increased in stages until the degradation efficiency was below 90%. The parameters to be controlled in order to reach continuous and stable operation were temperature, moisture content and the percentage of the compound to be degraded at the inlet and outlet gas streams (removal or elimination efficiency). When the H2S mass loading rate was between 10 and 40 g m(-3) h(-1), the removal efficiency was greater than 90%. The support material had a good physical performance throughout operation time, which is evidence that this material is suitable for biofiltration purposes.


Subject(s)
Biodegradation, Environmental , Filtration/methods , Hydrogen Sulfide/metabolism , Gases
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