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1.
Artículo en Inglés | MEDLINE | ID: mdl-38972351

RESUMEN

BACKGROUND: Perioperative cognitive dysfunction (PCD) is a very prevalent clinical syndrome due to the progressive aging of the surgical population.The aim of our study is to evaluate the clinical practice of Spanish anesthesiologists surveyed regarding this entity. MATERIAL AND METHODS: Prospective online survey conducted by the Neurosciences Section and distributed by SEDAR. RESULTS: 544 responses were obtained, with a participation rate of 17%. 54.4% of respondents never make a preoperative assessment of cognitive impairment, only 7.5% always do it. 79.6% lack an intraoperative management protocol for the patient at risk of PCD. In the anesthetic planning, only 23.3% of the patients was kept in mind. Eighty-nine percent considered regional anesthesia with or without sedation preferable to general anesthesia for the prevention of PCD. 88.8% considered benzodiazepines to present a high risk of PCD. 71.7% considered that anesthetic depth monitoring could prevent postoperative cognitive deficit. Routine evaluation of postoperative delirium is low, only 14%. More than 80% recognize that PCD is underdiagnosed. CONCLUSIONS: Among Spanish anesthesiologists surveyed, PCD is still a little known and underappreciated entity. It is necessary to raise awareness of the need to detect risk factors for PCD, as well as postoperative assessment and diagnosis. Therefore, the development of guidelines and protocols and the implementation of continuing education programs in which anesthesiologists should be key members of multidisciplinary teams in charge of perioperative care are suggested.

2.
Rev Esp Anestesiol Reanim (Engl Ed) ; 68(2): 82-98, 2021 Feb.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32624233

RESUMEN

The present work aims to establish a guide to action, agreed by anaesthesiologists and neurophysiologists alike, to perform effective intraoperative neurophysiological monitoring for procedures presenting a risk of functional neurological injury, and neurosurgical procedures. The first section discusses the main techniques currently used for intraoperative neurophysiological monitoring. The second exposes the anaesthetic and non-anaesthetic factors that are likely to affect the electrical records of the nervous system structures. This section is followed by an analysis detailing the adverse effects associated with the most common techniques and their use. Finally, the last section describes a series of guidelines to be followed upon the various intraoperative clinical events.


Asunto(s)
Anestésicos , Monitorización Neurofisiológica Intraoperatoria , Consenso , Procedimientos Neuroquirúrgicos/efectos adversos
3.
Waste Manag ; 95: 171-181, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31351602

RESUMEN

Biomasses valorization by pyrolysis is a good option for reducing environmental problems. In this study, the environmental performance of three Mexican biomass valorizations (castor husk, coffee pulp and Pinus sawdust) by the pyrolysis was compared. The environmental impacts of all equipment involved in pyrolysis were evaluated. In addition, the financial viability of pyrolysis technology of coffee pulp was studied. The biomass with the lowest impact for all the selected categories was the Pinus sawdust, followed by castor husk and coffee pulp. The GWP category had values greater than 700 kg CO2eq for all the biomass studied. GWP category is caused by the emissions, mainly due to the high amounts of CH4 and CO2 released for all the studied biomasses. Furthermore, the equipment with the greatest impact are the separator, the pyrolyzer and the cyclone. Finally, it was observed that even the least favorable biomass with the environment is viable from a financial point of view.


Asunto(s)
Pinus , Pirólisis , Biomasa , Ambiente , Madera
4.
Waste Manag ; 58: 230-240, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27595497

RESUMEN

Due to the depletion of fossil fuel reserves and the environmental issues derived from their use, biomass seems to be an excellent source of renewable energy. In this work, the kinetics of the pyrolysis and combustion of three different biomass waste samples (two dairy manure samples before (Pre) and after (Dig R) anaerobic digestion and one swine manure sample (SW)) was studied by means of thermogravimetric analysis. In this work, three iso-conversional methods (Friedman, Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS)) were compared with the Coats-Redfern method. The Ea values of devolatilization stages were in the range of 152-170kJ/mol, 148-178kJ/mol and 156-209kJ/mol for samples Pre, Dig R and SW, respectively. Concerning combustion process, char oxidation stages showed lower Ea values than that obtained for the combustion devolatilization stage, being in the range of 140-175kJ/mol, 178-199kJ/mol and 122-144kJ/mol for samples Pre, Dig R and SW, respectively. These results were practically the same for samples Pre and Dig R, which means that the kinetics of the thermochemical processes were not affected by anaerobic digestion. Finally, the distributed activation energy model (DAEM) and the pseudo-multi component stage model (PMSM) were applied to predict the weight loss curves of pyrolysis and combustion. DAEM was the best model that fitted the experimental data.

5.
Rev Esp Anestesiol Reanim ; 63(8): 459-70, 2016 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-26143337

RESUMEN

A detailed analysis of the literature on consciousness and cognition mechanisms based on the neural networks theory is presented. The immune and inflammatory response to the anesthetic-surgical procedure induces modulation of neuronal plasticity by influencing higher cognitive functions. Anesthetic drugs can cause unconsciousness, producing a functional disruption of cortical and thalamic cortical integration complex. The external and internal perceptions are processed through an intricate network of neural connections, involving the higher nervous activity centers, especially the cerebral cortex. This requires an integrated model, formed by neural networks and their interactions with highly specialized regions, through large-scale networks, which are distributed throughout the brain collecting information flow of these perceptions. Functional and effective connectivity between large-scale networks, are essential for consciousness, unconsciousness and cognition. It is what is called the "human connectome" or map neural networks.


Asunto(s)
Anestésicos/farmacología , Encéfalo , Cognición , Estado de Conciencia , Inconsciencia , Humanos
6.
Phys Chem Chem Phys ; 16(7): 2962-70, 2014 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-24390482

RESUMEN

The optimization of graphene growth on copper foils using an atmospheric pressure chemical vapor deposition setup is reported. CH4 and H2 were used as precursor gases and Raman spectroscopy as the main graphene characterization technique. Different growth parameters, including temperature and reaction time, the molar ratio of CH4/H2 in the feed and total flow of gases during the reaction step, were studied in detail. It was shown that graphene growth was not homogeneous in the entire sample, multilayer graphene was present in most of the sample, however as the synthesis parameters were optimized, graphene gained better quality, obtaining bilayer graphene over most of the sheet in the final optimized sample. Homemade software was used to analyze the quality of the synthesised graphene, obtaining a more quality graphene according to the synthesis parameters optimized. An optimal bilayer graphene sample was prepared at the lowest growth time (10 min) and the highest synthesis temperature (1050 °C), using a CH4/H2 flow ratio and a total flow rate ratio of precursors of 7% and 60 Nml (CH4 + H4) per min respectively.

7.
Bioresour Technol ; 143: 562-74, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23835261

RESUMEN

Combustion characteristics of biomass main components and three lignocellulosic biomass (fir wood, eucalyptus wood and pine bark) were investigated by thermogravimetric analysis coupled with mass spectrometry. The combustion of biomass was divided into two main steps, devolatilization and char oxidation stage. Heating rate effect was also studied. Generally, the higher the heating rate, the higher the decomposition temperature. Furthermore, the weight loss rate decreased due to particle temperature gradients. Combustion kinetics were studied. Models based on reaction order (Oi), nucleation (Ni) and diffusion (Di) achieved the best fitting to the experimental data. Cellulose oxidation presented the highest activation energies. CO, CO2 and H2O were the main components evolved from combustion. Additionally, light hydrocarbons (CH4 and C2H5) were also present. Finally, nitrogen compounds were in a higher proportion than sulfur compounds being released as primary amines and NOx.


Asunto(s)
Biomasa , Lignina/metabolismo , Espectrometría de Masas , Termogravimetría , Cinética , Lignina/química
8.
Phys Chem Chem Phys ; 15(29): 12104-17, 2013 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-23652211

RESUMEN

The increasing interest in ammonia decomposition is due to the fact that this compound can be used advantageously as a hydrogen carrier, allowing the development of single-step hydrogen generation systems. With the aim of developing efficient reactors for ammonia decomposition, e.g. for fuel cell applications, it is imperative to investigate the kinetics and reaction mechanism in depth. The main goal of this work is to develop reliable kinetic models that are able to predict the performance obtained using integral reactors, e.g. monoliths. In this case, an almost complete NH3 conversion is obtained, with a high H2 concentration at the exit of the reactor. The operating conditions, mainly the gas composition, are very different along the reactor. In addition, the temperatures needed to attain such large conversions are usually high. The kinetic models developed in this contribution are based on the Langmuir isotherm, considering that all the adsorbed species can be kinetically relevant, that the slow step or steps can be partially reversible, and that the surface can be considered as energetically uniform, i.e. ideal. Among other conclusions, the results obtained indicate that the variable kinetic orders and apparent activation energies frequently reported in the literature can be direct consequences of the data analysis and can therefore also be explained without considering any change in the controlling step with the reaction temperature or in the hydrogen or ammonia concentration.

9.
Bioresour Technol ; 130: 321-31, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23313676

RESUMEN

Pyrolysis, combustion and gasification characteristics of Nannochloropsis gaditana microalgae (NG microalgae) were investigated by thermogravimetric analysis (TGA). NG microalgae pyrolysis and combustion could be divided into three main stages: dehydration, proteins and polysaccharides degradation and char decomposition. The effects of the initial sample mass, particle size and gas flow on the pyrolysis and combustion processes were studied. In addition, gasification operation conditions such as temperature, initial sample mass, particle size, sweep gas flow and steam concentration, were experimentally evaluated. The evolved gases were analyzed online using mass spectroscopy (MS). In pyrolysis and combustion processes, most of the gas products were generated at the second degradation step. N-compounds evolution was associated with the degradation of proteins. Furthermore, SO(2) release from combustion could be related to sulphated polysaccharides decomposition. The main products detected during gasification were CO(2), CO, H(2), indicating that oxidation reactions, water gas and water gas shift reactions, were predominant.


Asunto(s)
Biocombustibles , Microalgas , Espectrometría de Masas , Termogravimetría
10.
Bioresour Technol ; 109: 163-72, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22297048

RESUMEN

The pyrolysis characteristics of three lignocellulosic biomasses (fir wood, eucalyptus and pine bark) and a marine biomass (Nannochloropsis gaditana microalgae) were investigated by thermogravimetric analysis coupled with mass spectrometry (TGA-MS). Thermal degradation of lignocellulosic biomass was divided into four zones, corresponding to the decomposition of their main components (cellulose, hemicellulose and lignin) and a first step associated to water removal. Differences in volatile matter and cellulose content of lignocellulosic species resulted in different degradation rates. Microalgae pyrolysis occurred in three stages due to the main components of them (proteins), which are greatly different from lignocellulosic biomass. Heating rate effect was also studied. The main gaseous products formed were CO(2), light hydrocarbons and H(2)O. H(2) was detected at high temperatures, being associated to secondary reactions (char self-gasification). Pyrolysis kinetics were studied using a multiple-step model. The proposed model successfully predicted the pyrolytic behaviour of these samples resulting to be statistically meaningful.


Asunto(s)
Organismos Acuáticos/química , Biomasa , Lignina/análisis , Lignina/química , Espectrometría de Masas/métodos , Temperatura , Termogravimetría/métodos , Gases/análisis , Calor , Cinética , Microalgas/química , Madera/química , Xilanos/química
12.
Hum Exp Toxicol ; 20(2): 118-9, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11327512

RESUMEN

We report a case of fatal weeverfish sting. An 18-year-old man was stung on the left leg by a weeverfish, which he was attempting to capture while snorkelling off the coast of Majorca (Spain). The man felt intense pain, but managed to swim to his boat where he lost consciousness after boarding rapidly. An hour later, when examined by a doctor, the subject was found to be in cardiorespiratory arrest. Reanimation manoeuvres were unsuccessful. The most import post-mortem findings were in the skin and lungs. A puncture wound, which traversed the greater saphenous vein and was covered by an intense haemorrhagic infiltrate, was observed in the skin. The lungs showed haemorrhagic alveolar oedema.


Asunto(s)
Mordeduras y Picaduras , Venenos de los Peces/efectos adversos , Perciformes , Adolescente , Animales , Buceo , Resultado Fatal , Humanos , Masculino , España
13.
Int J Legal Med ; 114(1-2): 130-2, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11197620

RESUMEN

A population database was generated from 118 unrelated Caucasoid individuals living in Spain. Sequence polymorphisms of the mitochondrial DNA (mtDNA) control region, hypervariable regions I and II (HVRI and HVRII) were determined using the polymerase chain reaction (PCR) and direct sequencing. A total of 102 different sequences were found as defined by 105 variable positions. The most common sequence occurred six times, and this sequence is also the most frequent in other European populations such as Austria, Germany and Britain. The mean pair-wise difference for the two HVR regions taken together was 7.74. The study revealed that transitions made up the majority of the variations (88%), whereas we observed a significantly lower frequency of transversions (8%). Also one individual in this study was observed with two positions of heteroplasmy at nucleotides 150 (C/T) and 153 (G/A). A statistical estimate of the results for this population showed a genetic diversity of 0.99. The probability of two random individuals showing identical mtDNA haplotypes is 1.3%. In order to use the mtDNA analysis in forensic casework, we consider that it is of crucial importance to know the frequency of the different sequences of mtDNA, and this data base study could be a useful tool to statistically evaluate the results.


Asunto(s)
ADN Mitocondrial/genética , Variación Genética , Polimorfismo Genético , Automatización , Dermatoglifia del ADN , Análisis Mutacional de ADN , Haplotipos/genética , Humanos , Reacción en Cadena de la Polimerasa/instrumentación , España , Población Blanca/genética
14.
ISA Trans ; 38(3): 231-41, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10560141

RESUMEN

In this paper, several tuning algorithms, specifically ITAE, IMC and Cohen and Coon, were applied in order to tune an activated sludge aeration PID controller. Performance results of these controllers were compared by simulation with those obtained by using a nonlinear fuzzy PID controller. In order to design this controller, a trial and error procedure was used to determine, as a function of error at current time and at a previous time, sets of parameters (including controller gain, integral time and derivative time) which achieve satisfactory response of a PID controller actuating over the aeration process. Once these sets of data were obtained, neural networks were used to obtain fuzzy membership functions and fuzzy rules of the fuzzy PID controller.


Asunto(s)
Lógica Difusa , Aguas del Alcantarillado , Algoritmos , Biomasa , Simulación por Computador , Cinética , Dinámicas no Lineales , Consumo de Oxígeno
15.
Ann Pharm Fr ; 57(1): 16-26; discussion 27-8, 1999 Jan.
Artículo en Francés | MEDLINE | ID: mdl-10073047

RESUMEN

The European Community has established a fundamental condition for opening a pharmaceutical laboratory, i.e. the designation of a qualified person having the professional profile detailed in the European Community Directive and who is responsible for implementing specific obligations. It is the final responsibility of this qualified person to release medicine on the market. Do to the importance of this person, we have analyzed his/her functions, obligations and responsibilities. The training required to fulfil the functions of a qualified person is presented. The profiles of qualified persons in the most representative European countries are discussed to demonstrate analogies and differences in national legislations and their adaptation to European Community regulations.


Asunto(s)
Laboratorios/normas , Competencia Profesional , Evaluación de Medicamentos , Unión Europea
16.
Am J Forensic Med Pathol ; 19(2): 148-51, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9662110

RESUMEN

We report a case of suicide following ingestion of a large dose of 3,4-methylenedioxyethamphetamine (MDEA, "Eve") in a 27-year-old woman with a history of depression. Several days before her death, she had attempted suicide with benzodiazepines resulting in a 24-hour hospital admission; at that time, no physiologic abnormalities were detected. Findings on autopsy were nonspecific. Toxicologic analysis showed a high concentration of MDEA and the appearance of benzodiazepines in body fluids. Ethanol and other drugs of abuse were not found. We discuss the clinical manifestations, toxicologic syndromes, and mechanisms of death with amphetamine intoxication. MDEA intoxication in young people may result in sudden death.


Asunto(s)
3,4-Metilenodioxianfetamina/análogos & derivados , Drogas de Diseño/envenenamiento , Suicidio , 3,4-Metilenodioxianfetamina/metabolismo , 3,4-Metilenodioxianfetamina/envenenamiento , Adulto , Cromatografía de Gases/métodos , Sobredosis de Droga , Resultado Fatal , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos
17.
Int J Legal Med ; 110(4): 223-5, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9274949

RESUMEN

Population data studies were carried out on a Caucasian population from North-East Spain (n = 129-292 individuals) for 13 PCR-based polymorphic DNA loci: six short tandem repeat loci (HumTH01, HumTPOX, HumCSF1PO, HumF13A01, HumFES/FPS, HumvWFA31), the six PM loci (HLA-DQ alpha, LDLR, GYPA, HBGG, D7S8, GC) and one variable number tandem repeat locus (D1S80). The genotypes distributions were in accordance with Hardy-Weinberg expectations. The combined use of the 13 polymorphic systems provides a high power of discrimination and power of exclusion for use in forensic casework and paternity testing.


Asunto(s)
Alelos , ADN/genética , Frecuencia de los Genes/genética , Marcadores Genéticos/genética , Reacción en Cadena de la Polimerasa , Femenino , Genética de Población , Genotipo , Humanos , Masculino , Paternidad , Secuencias Repetitivas de Ácidos Nucleicos/genética , España
18.
Addiction ; 91(3): 419-26, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8867204

RESUMEN

Drug-related deaths have become a major source of premature mortality. This paper presents an analysis of deaths due to acute adverse drug reactions caused by opiates or cocaine in the city of Barcelona over a 5-year period during which figures were stable. Annual mortality rates due to adverse drug reactions of city residents for the 1989-93 period were estimated to be 15.3 per 100,000 people in the 15-49-year age group. Mortality rates for men (25.0) are consistently higher than mortality rates for women (5.8). Mortality rates by age group show different patterns by gender. Males in the 25-29-year group have the highest mortality rate (62.8), almost doubling the rates for the 20-24 (36.1) and 30-34 (33.3)-year groups. The highest differential in age-specific mortality by gender is seen in the 35-39-year age group, where mortality rates for men (21.5) are eight times higher than for women (2.6 per 100,000). The distribution by place of residence, stratifying data across city neighbourhoods and municipal districts displays wide differences between districts in the mean annual rates, ranking between 77.3 and 8.3 per 100,000, a nine-fold magnitude. Differences are even steeper when we break down data by neighbourhood. Although all areas with high adverse drug reactions mortality are areas of low socio-economic level, a more complex association between deprivation and drug use must exist, as other areas with similarly low socio-economic indicators do not suffer from such high mortality. A cross-tabulation of place of residence and district of death shows that for most adverse drug reaction deaths, death takes place in the district of residence but patterns related to districts who attract drug-related deaths and districts who export them may be observed. These results provide new insights into the epidemiology of substance abuse in Barcelona, where it follows patterns that may be similar to those of other major urban areas in Spain, but also in other Southern European countries.


Asunto(s)
Cocaína/envenenamiento , Sobredosis de Droga/mortalidad , Narcóticos/envenenamiento , Trastornos Relacionados con Opioides/mortalidad , Trastornos Relacionados con Sustancias/mortalidad , Población Urbana/estadística & datos numéricos , Adolescente , Adulto , Causas de Muerte , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , España/epidemiología
20.
Med Clin (Barc) ; 105(12): 441-5, 1995 Oct 14.
Artículo en Español | MEDLINE | ID: mdl-7490933

RESUMEN

BACKGROUND: Mortality caused by acute adverse drug reactions (AADR) increased in Spain over the eighties and has become one of the major causes of death for youth. This paper presents the results of a study in the city of Barcelona during the 1983-92 decade; based in the city drug information system. METHODS: The study includes all deaths caused by AADR autopsied in the Forensic Institute between 1983 and 1992. Mortality of city residents is analyzed by cohort, grouping data in two-years and adjusting Poisson regression to mortality rates by age group, birth cohort and period of study. RESULTS: During this period a sharp increase in AADR mortality is seen, as there were 19 deaths in the city in 1983 and 160 in 1992. The increase concentrates in the years 1987-89. Although previously the increasing mortality of drug users was related by some observers with the progressive deterioration of their health status, linked to their increasing age and to the cumulative effects of years of substance dependence, the mortality analysis points to a clear period effect, resulting in an increased mortality across all age groups, for cohorts born after 1960. CONCLUSIONS: These results point to changes in the illegal drug market in the city or in the patterns of abuse as most likely causes for the increase. The results also suggest that since 1989 there is a stabilization in mortality due to AADR, which deserves further study.


Asunto(s)
Drogas Ilícitas/envenenamiento , Trastornos Relacionados con Sustancias/mortalidad , Población Urbana/estadística & datos numéricos , Enfermedad Aguda , Adolescente , Adulto , Distribución por Edad , Causas de Muerte , Estudios de Cohortes , Sobredosis de Droga/mortalidad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Análisis de Regresión , España/epidemiología
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