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1.
Rev Esp Anestesiol Reanim (Engl Ed) ; 68(2): 82-98, 2021 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32624233

RESUMO

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.


Assuntos
Anestésicos , Monitorização Neurofisiológica Intraoperatória , Consenso , Procedimentos Neurocirúrgicos/efeitos adversos
2.
Waste Manag ; 95: 171-181, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31351602

RESUMO

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.


Assuntos
Pinus , Pirólise , Biomassa , Meio Ambiente , Madeira
3.
Waste Manag ; 58: 230-240, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27595497

RESUMO

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.

4.
Rev Esp Anestesiol Reanim ; 63(8): 459-70, 2016 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26143337

RESUMO

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.


Assuntos
Anestésicos/farmacologia , Encéfalo , Cognição , Estado de Consciência , Inconsciência , Humanos
5.
Phys Chem Chem Phys ; 16(7): 2962-70, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24390482

RESUMO

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.

6.
Bioresour Technol ; 143: 562-74, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23835261

RESUMO

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.


Assuntos
Biomassa , Lignina/metabolismo , Espectrometria de Massas , Termogravimetria , Cinética , Lignina/química
7.
Phys Chem Chem Phys ; 15(29): 12104-17, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23652211

RESUMO

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.

8.
Bioresour Technol ; 130: 321-31, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23313676

RESUMO

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.


Assuntos
Biocombustíveis , Microalgas , Espectrometria de Massas , Termogravimetria
9.
Bioresour Technol ; 109: 163-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22297048

RESUMO

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.


Assuntos
Organismos Aquáticos/química , Biomassa , Lignina/análise , Lignina/química , Espectrometria de Massas/métodos , Temperatura , Termogravimetria/métodos , Gases/análise , Temperatura Alta , Cinética , Microalgas/química , Madeira/química , Xilanos/química
11.
Hum Exp Toxicol ; 20(2): 118-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11327512

RESUMO

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.


Assuntos
Mordeduras e Picadas , Venenos de Peixe/efeitos adversos , Perciformes , Adolescente , Animais , Mergulho , Evolução Fatal , Humanos , Masculino , Espanha
12.
Int J Legal Med ; 114(1-2): 130-2, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11197620

RESUMO

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.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Polimorfismo Genético , Automação , Impressões Digitais de DNA , Análise Mutacional de DNA , Haplótipos/genética , Humanos , Reação em Cadeia da Polimerase/instrumentação , Espanha , População Branca/genética
13.
ISA Trans ; 38(3): 231-41, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10560141

RESUMO

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.


Assuntos
Lógica Fuzzy , Esgotos , Algoritmos , Biomassa , Simulação por Computador , Cinética , Dinâmica não Linear , Consumo de Oxigênio
14.
Ann Pharm Fr ; 57(1): 16-26; discussion 27-8, 1999 Jan.
Artigo em Francês | MEDLINE | ID: mdl-10073047

RESUMO

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.


Assuntos
Laboratórios/normas , Competência Profissional , Avaliação de Medicamentos , União Europeia
15.
Am J Forensic Med Pathol ; 19(2): 148-51, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9662110

RESUMO

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.


Assuntos
3,4-Metilenodioxianfetamina/análogos & derivados , Drogas Desenhadas/envenenamento , Suicídio , 3,4-Metilenodioxianfetamina/metabolismo , 3,4-Metilenodioxianfetamina/envenenamento , Adulto , Cromatografia Gasosa/métodos , Overdose de Drogas , Evolução Fatal , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos
16.
Int J Legal Med ; 110(4): 223-5, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9274949

RESUMO

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.


Assuntos
Alelos , DNA/genética , Frequência do Gene/genética , Marcadores Genéticos/genética , Reação em Cadeia da Polimerase , Feminino , Genética Populacional , Genótipo , Humanos , Masculino , Paternidade , Sequências Repetitivas de Ácido Nucleico/genética , Espanha
17.
Addiction ; 91(3): 419-26, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8867204

RESUMO

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.


Assuntos
Cocaína/envenenamento , Overdose de Drogas/mortalidade , Entorpecentes/envenenamento , Transtornos Relacionados ao Uso de Opioides/mortalidade , Transtornos Relacionados ao Uso de Substâncias/mortalidade , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Causas de Morte , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espanha/epidemiologia
19.
Med Clin (Barc) ; 105(12): 441-5, 1995 Oct 14.
Artigo em Espanhol | MEDLINE | ID: mdl-7490933

RESUMO

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.


Assuntos
Drogas Ilícitas/envenenamento , Transtornos Relacionados ao Uso de Substâncias/mortalidade , População Urbana/estatística & dados numéricos , Doença Aguda , Adolescente , Adulto , Distribuição por Idade , Causas de Morte , Estudos de Coortes , Overdose de Drogas/mortalidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Espanha/epidemiologia
20.
J Forensic Sci ; 35(3): 740-5, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2348187

RESUMO

Intestinal ischemia induced by cocaine abuse is a rare condition. To this date, only three cases have been described. The diagnosis of bowel ischemia should be suspected whenever a cocaine addict has severe abdominal pain. A pathological examination of the resected bowel segment was performed in one case, and the diagnosis was confirmed microscopically. However, the existence of pathologic alterations of the intestinal vessels was not confirmed. Why the intestinal injury is segmental and whether it is related to the dose ingested, the administration route, or the combination of cocaine with alcohol, caffeine, or marijuana remain unclear. The authors report one fatal case associated with cocaine-alcohol overdose. The postmortem examination demonstrated the existence of segmental intestinal ischemia. Microscopic study failed to demonstrate thrombosis in the mesenteric vessels; however, we found an unusual lesion affecting the arterioles located in the intestinal submucosa of the hemorrhagic areas.


Assuntos
Intoxicação Alcoólica/complicações , Cocaína/envenenamento , Intestino Delgado/irrigação sanguínea , Isquemia/etiologia , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Arteríolas/patologia , Cocaína/análogos & derivados , Cocaína/urina , Overdose de Drogas/complicações , Etanol/sangue , Humanos , Isquemia/patologia , Masculino
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