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To evaluate the potential of compost based on municipal solid waste (MSW) and 20% legume pruning under a pyrolysis process, generated products, including solids (biochar), liquids (bio-oil), and gases (non-condensable gases), through experimentation in a pilot plant with a fluidized bed reactor at 450°C and gas chromatography/mass spectrometry have been analysed. In addition, the compost kinetic behaviour by thermogravimetric analysis (TGA), using the Flynn-Wall-Ozawa (FWO) method, has been investigated. Four different reaction zones, associated with lignocellulosic materials (hemicellulose, cellulose, and lignin) with a first step for water evaporation, in TGA curve have been observed. A biochar with low stability and aromaticity, considering high and low O/C and H/C ratios, respectively, has been obtained. The obtained pyrolytic liquids contain a high concentration of phenolic compounds because of a significant presence of lignins and other high molecular weight compounds in the original material. Moreover, the generated non-condensable gases consist mainly of short-chain compounds, such as alcohols, aldehydes, and alkenes produced from hemicellulose, cellulose, and proteins.
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Objective: Initial COVID-19 reports described a variety of clinical presentations, but lower respiratory abnormalities are most common and chest CT findings differ between adult and pediatric patients. We aim to summarize early CT findings to inform healthcare providers on the frequency of COVID-19 manifestations specific to adult or pediatric patients, and to determine if the sensitivity of CT justifies its use in these populations. Methods: PubMed was searched for the presence of the words "CT, imaging, COVID-19" in the title or abstract, and 17 large-scale PubMed and/or Scopus studies and case reports published between January 1, 2020 and April 15, 2020 were selected for data synthesis. Results: Initial CT scans identified ground-glass opacities and bilateral abnormalities as more frequent in adults (74%, n = 698, and 89%, n = 378, respectively) than children (60%, n = 25, and 37%, n = 46). At 14+ days, CT scans evidenced varied degrees of improvement in adults but no resolution until at least 26 days after the onset of flu-like symptoms. In pediatric patients, a third (n = 9) showed additional small nodular GGOs limited to a single lobe 3-5 days after an initial CT scan. Conclusión: Early adult CT findings suggest the limited use of CT as a supplemental tool in diagnosing COVID-19 in symptomatic adult patients, with a particular focus on identifying right and left lower lobe abnormalities, GGOs, and interlobular septal thickening. Early pediatric CT findings suggest against the use of CT if RT-PCR is available given its significantly lower sensitivity in this population and radiation exposure.
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MSW compost valorization under combustion, at two different composting process conditions, have been studied by thermogravimetric analysis (TGA). The composting operating parameters such as aeration and moisture affect the biodegradability of compost and results of the combustion (different gross heating values for each reactors). The obtained TGA showed that maximum weight loss for 10-12% (245-247⯰C), 32-34% (407-411⯰C) and 44-46% (760-769⯰C) in correspondence to hemicellulose, cellulose and lignin-humic-fulvic acids decomposition for each reactor are observed. Obtained valued in kinetic study (Flynn-Wall-Ozawa method) results in suitable coefficients of determination. In that form, to establish the assumption that combustion of compost under a first-order reaction may be appropriate. Moreover, in both reactors, the conversion rate increased and the activation energy decreased with composting time is found. The maximum gross heating value versus minimum activation energy (for αâ¯=â¯0.25 and αâ¯=â¯0.5) corresponds to final composts and under aeration of 0.050 and 0.175 Lair kg-1 d-1 and moisture of 40% and 55% for R1 and R2 reactors respectively. For MSW, under proper conditions, composting could be used as a suitable biodrying process, stabilizing and concentrating the heating value.
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Compostaje , Celulosa , Sustancias Húmicas , Lignina , SueloRESUMEN
Taking into account the influence of Si in osteoblast cell proliferation, a series of sol-gel derived silicon based coating was prepared by controlling the process parameters and varying the different Si-alkoxide precursors molar rate in order to obtain materials able to release Si compounds. For this purpose, methyltrimethoxysilane (MTMOS) and tetraethyl orthosilicate (TEOS) were hydrolysed together and the sol obtained was used to dip-coat the different substrates. The silicon release ability of the coatings was tested finding that it was dependent on the TEOS precursor content, reaching a Si amount value around ninefolds higher for coatings with TEOS than for the pure MTMOS material. To test the effect of this released Si, the in vitro performance of developed coatings was tested with human adipose mesenchymal stem cells finding a significantly higher proliferation and mineralization on the coating with the higher TEOS content. For in vivo evaluation of the biocompatibility, coated implants were placed in the tibia of the rabbit and a histological analysis was performed. The evaluation of parameters such as the bone marrow state, the presence of giant cells and the fibrous capsule proved the biocompatibility of the developed coatings. Furthermore, coated implants seemed to produce a qualitatively higher osteoblastic activity and a higher number of bone spicules than the control (uncoated commercial SLA titanium dental implant).
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Implantes Dentales , Silicio/química , Animales , Materiales Biocompatibles , Desarrollo Óseo , Médula Ósea , Ensayo de Materiales , ConejosRESUMEN
Surface engineering of biomaterials could promote the osseointegration of implants. In this work, two types of hybrid sol-gel materials were developed to stimulate cell attachment, proliferation and differentiation of osteogenic cells. One type was synthesised from vinyl triethoxysilane (VTES) and tetraethyl-orthosilicate (TEOS) at different molar ratios, while the other from VTES and hydroxyapatite particles (HAp). Hybrid materials were systematically investigated using nuclear magnetic resonance, Fourier transform infrared spectroscopy and contact angle metrology. The biocompatibility and osseoinduction of the coatings were evaluated by measuring mesenchymal stem cell proliferation using MTT assays and analysing the mineralised extracellular matrix production by quantifying calcium-rich deposits. The results highlighted the versatility of these coatings in obtaining different properties by changing the molar ratio of the VTES:TEOS precursors. Thus, mineralisation was stimulated by increasing TEOS content, while the addition of HAp improved cell proliferation but worsened mineralisation.
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Durapatita/química , Células Madre Mesenquimatosas/citología , Osteoblastos/citología , Silanos/química , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/síntesis química , Adhesión Celular/fisiología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Ensayo de Materiales , Células Madre Mesenquimatosas/fisiología , Osteoblastos/fisiología , Osteogénesis/fisiología , Transición de FaseRESUMEN
Composting is one of the most successful biological processes for the treatment of the residues enriched in putrescible materials. The optimization of parameters which have an influence on the stability of the products is necessary in order to maximize recycling and recovery of waste components. The influence of the composting process parameters (aeration, moisture, C/N ratio, and time) on the stability parameters (organic matter, N-losses, chemical oxygen demand, nitrate, biodegradability coefficient) of the compost was studied. The composting experiment was carried out using Municipal Solid Waste (MSW) and Legume Trimming Residues (LTR) in 200 L isolated acrylic barrels following a Box-Behnken central composite experimental design. Second-order polynomial models were found for each of the studied compost stability parameter, which accurately described the relationship between the parameters. The differences among the experimental values and those estimated by using the equations never exceeded 10% of the former. Results of the modelling showed that excluding the time, the C/N ratio is the strongest variable influencing almost all the stability parameters studied in this case, with the exception of N-losses which is strongly dependent on moisture. Moreover, an optimized ratio MSW/LTR of 1/1 (w/w), moisture content in the range of 40-55% and moderate to low aeration rate (0.05-0.175 Lair kg(-)(1) min(-1)) is recommended to maximise degradation and to obtain a stable product during co-composting of MSW and LTR.
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Fabaceae/metabolismo , Modelos Teóricos , Suelo , Residuos Sólidos , Administración de Residuos/métodos , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Carbono/metabolismo , Nitratos , Nitrógeno/metabolismoRESUMEN
Leucaena leucocephala is a fast-growing leguminous biomass with great energetical and value-added chemical compounds potential (saccharides, biogas, bio-oil, etc.). Using the thermogravimetric and derivative thermogravimetric curves, the different trends followed by L. leucocephala during pyrolysis, 0.25 equivalence ratio (ER) of gasification, 0.50 equivalence ratio of gasification and combustion were analyzed, and the activation energies were obtained by Distributed Activation Energy Model (DAEM) method. Gas samples were collected through adsorption tubes during the gasification at 0.25 ER and 0.50 ER to observe the distribution of the main chemical products in this process by gas chromatography/mass spectrometry and were compared with pyrolysis products. It was found that small amounts of oxygen have changes in the kinetics of the process, leading to significant decreases in the activation energy at the beginning of the degradation of components such as cellulose (from 170 to 135 kJ mol-1 at 0.25 conversion at 0.50 ER gasification). The activation energy of lignin disintegration was also reduced (342 kJ mol-1), assimilating the beginnings of gasification processes such as the Boudouard reaction. 0.50 ER gasification is potentially an interesting process to obtain quality bio-oil, since a large amount of hexane is detected (44.96%), and value-added oxygenated intermediates such as alcohols and glycols. Gasification at 0.25 ER, on the other hand, is much more similar to pyrolysis, obtaining a wide variety of short-chain compounds resulting from the disintegration of the main lignocellulosic components, especially ketones such as 1-hydroxypropan-2-one (19.48%), and notable amount of furans and anhydrosugars like d-allose (5.50%).
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AIMS/HYPOTHESIS: We examined the independent and combined associations of physical activity and obesity with incident type 2 diabetes in men and women. METHODS: The InterAct case-cohort study consists of 12,403 incident type 2 diabetes cases and a randomly selected subcohort of 16,154 individuals, drawn from a total cohort of 340,234 participants with 3.99 million person-years of follow-up. Physical activity was assessed by a four-category index. Obesity was measured by BMI and waist circumference (WC). Associations between physical activity, obesity and case-ascertained incident type 2 diabetes were analysed by Cox regression after adjusting for educational level, smoking status, alcohol consumption and energy intake. In combined analyses, individuals were stratified according to physical activity level, BMI and WC. RESULTS: A one-category difference in physical activity (equivalent to approximately 460 and 365 kJ/day in men and women, respectively) was independently associated with a 13% (HR 0.87, 95% CI 0.80, 0.94) and 7% (HR 0.93, 95% CI 0.89, 0.98) relative reduction in the risk of type 2 diabetes in men and women, respectively. Lower levels of physical activity were associated with an increased risk of diabetes across all strata of BMI. Comparing inactive with active individuals, the HRs were 1.44 (95% CI 1.11, 1.87) and 1.38 (95% CI 1.17, 1.62) in abdominally lean and obese inactive men, respectively, and 1.57 (95% CI 1.19, 2.07) and 1.19 (95% CI 1.01, 1.39) in abdominally lean and obese inactive women, respectively. CONCLUSIONS/INTERPRETATION: Physical activity is associated with a reduction in the risk of developing type 2 diabetes across BMI categories in men and women, as well as in abdominally lean and obese men and women.
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Diabetes Mellitus Tipo 2/epidemiología , Actividad Motora , Obesidad/epidemiología , Circunferencia de la Cintura , Índice de Masa Corporal , Estudios de Cohortes , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/prevención & control , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Humanos , Incidencia , Estilo de Vida , Masculino , Persona de Mediana Edad , Obesidad/genética , Obesidad/prevención & control , Factores de Riesgo , Encuestas y Cuestionarios , Circunferencia de la Cintura/genéticaRESUMEN
INTRODUCTION: Living with cerebral palsy has consequences such as social interaction. Assistive technologies used for improving independence only focuses on biological and physiological variables. The main objective in this review is to synthesize the evidence on interventions with assistive technologies, including feedback systems, with the aim of discovering outcomes of social participation in children with cerebral palsy. METHODOLOGY: There were 5 databases from rehabilitation which showed 683 articles in which only 9 were included. RESULTS: The studies assessed social participation with several instruments. The majority suggested positive effects in activities such as: walking, writing, playing, and social interaction. There were tools such as electronic pencils, switches, and exoskeletons present. CONCLUSION: Due to the poor quality of the methodologies of these studies, the search does not establish solid conclusions. However, the evidence suggests that assistive technologies with feedback have a positive impact on aspects of social participation.
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Parálisis Cerebral , Dispositivos de Autoayuda , Parálisis Cerebral/rehabilitación , Niño , Retroalimentación , Humanos , Participación SocialRESUMEN
OBJECTIVE: Initial COVID-19 reports described a variety of clinical presentations, but lower respiratory abnormalities are most common and chest CT findings differ between adult and pediatric patients. We aim to summarize early CT findings to inform healthcare providers on the frequency of COVID-19 manifestations specific to adult or pediatric patients, and to determine if the sensitivity of CT justifies its use in these populations. METHODS: PubMed was searched for the presence of the words "CT, imaging, COVID-19" in the title or abstract, and 17 large-scale PubMed and/or Scopus studies and case reports published between January 1, 2020 and April 15, 2020 were selected for data synthesis. RESULTS: Initial CT scans identified ground-glass opacities and bilateral abnormalities as more frequent in adults (74%, n = 698, and 89%, n = 378, respectively) than children (60%, n = 25, and 37%, n = 46). At 14+ days, CT scans evidenced varied degrees of improvement in adults but no resolution until at least 26 days after the onset of flu-like symptoms. In pediatric patients, a third (n = 9) showed additional small nodular GGOs limited to a single lobe 3-5 days after an initial CT scan. CONCLUSION: Early adult CT findings suggest the limited use of CT as a supplemental tool in diagnosing COVID-19 in symptomatic adult patients, with a particular focus on identifying right and left lower lobe abnormalities, GGOs, and interlobular septal thickening. Early pediatric CT findings suggest against the use of CT if RT-PCR is available given its significantly lower sensitivity in this population and radiation exposure.
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COVID-19 , SARS-CoV-2 , Adulto , Niño , Pruebas Diagnósticas de Rutina , Humanos , Pulmón , Tomografía Computarizada por Rayos XRESUMEN
To investigate the effect of control parameters (moisture, aeration and C/N ratio) on the composting evolution (temperature, pH, O2 and volatile compounds (VCs)) of municipal solid waste and pine trimmings, a central composite experimental design was used. The ANFIS modelling obtained shows that all the independent parameters were clearly influenced by the studied parameters. The relative influence of the other independent variables on temperature was C/N > moisture > aeration. However, for pH, O2 and VCs followed the order C/N > aeration > moisture. Moreover, the results were concordant, with a positive relation between temperature and VCs. In this way, lower VCs contents in ambient atmosphere have been found by using medium-to-high aeration (< 0.1 l(air) kg(-1) min(-1)), medium-to-high C/N (60-77) and high moisture (> 55%).
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Pinus/química , Eliminación de Residuos/métodos , Suelo , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/análisisRESUMEN
OBJECTIVE: To assess the potential influence of the age in the clinical spectrum of giant cell arteritis (GCA). METHODS: The case records of all patients diagnosed with biopsy-proven GCA at the Department of Medicine of the Hospital Xeral-Calde (Lugo, Northwest Spain) between 1981 and 2006 were reviewed. RESULTS: During the period of study, 273 Lugo residents were diagnosed with biopsy-proven GCA. The mean age +/- standard deviation at the time of disease diagnosis was 75.1+/-6.8 years (median: 75 years; interquartile range 71-80 years). A longer delay to the diagnosis was observed in patients younger than 70 years of age (13.2+/-12.8 weeks) compared to those 70 years and older (9.4+/-10.2 weeks) (p=0.03). Patients younger than 70 years presented more frequently polymyalgia rheumatica (p=0.02), cerebrovascular accidents (p=0.004), peripheral arteriopathy of recent onset due to large artery stenosis (p=0.03) and high alkaline phosphatase values (p=0.001) than those 70 years and older. Individuals 70-79 years of age at the time of disease diagnosis had ESR values (90.2+/-22.8 mm/1st hour) lower than those observed in patients younger than 70 years (98.3+/-22.2 mm/1st hour) or 80 years and older (99.5+/-20.6 mm/1st hour) (p=0.005). However, no significant differences in the frequency of visual ischemic complications according to the age at the time of disease diagnosis were observed. CONCLUSION: The results from this study display differences in the clinical spectrum of the disease according to the age of disease onset.
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Arteritis de Células Gigantes/diagnóstico , Arteritis de Células Gigantes/patología , Arterias Temporales/patología , Factores de Edad , Anciano , Anciano de 80 o más Años , Biopsia , Sedimentación Sanguínea , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Arteritis de Células Gigantes/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Polimialgia Reumática/diagnóstico , Polimialgia Reumática/fisiopatología , Estudios RetrospectivosRESUMEN
Chickens were used to investigate kinetic properties including metabolism of flumequine after single IV and oral dose, and to study tissue depletion of flumequine after multiple oral doses. Plasma and tissue (muscle, kidney, liver and skin plus fat) concentrations of flumequine and its metabolite 7-hydroxyflumequine were determined using a HPLC method. After IV and oral administration (single-dose of 12 mg flumequine/kg bw), plasma concentration-time curves were best described by a two-compartment open model. Elimination half-life and mean residence time of flumequine in plasma were 6.91 and 5.90 h, respectively, after IV administration and 10.32 and 8.95 h after oral administration. Maximum plasma concentration was 3.62 microg/ml and interval from oral administration until maximum concentration was 1.43 h. Oral bioavailability was found to be 57%. Flumequine was converted to 7-hydroxyflumequine. After oral administration (24 mg/kg bw every 24 h for 5 days), renal and hepatic concentrations of flumequine (18-25 microg/kg) persisted for 4 days; however, at that time, flumequine residues were not detected in skin plus fat and muscle tissues. Flumequine administered at a dosage of 24 mg/kg bw every 24h for 5 days, with a withdrawal time of 2d ays, resulted in flumequine concentrations in target tissues that were less than the European Union maximal residue limits.
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Antiinfecciosos/farmacocinética , Fluoroquinolonas/farmacocinética , Administración Oral , Animales , Antiinfecciosos/administración & dosificación , Antiinfecciosos/metabolismo , Área Bajo la Curva , Disponibilidad Biológica , Pollos , Cromatografía Líquida de Alta Presión , Fluoroquinolonas/administración & dosificación , Fluoroquinolonas/metabolismo , Semivida , Inyecciones Intravenosas , Masculino , Distribución TisularRESUMEN
A central composite experimental design was used to investigate the influence of environmental composting parameters (moisture, aeration, particle size and time) for legume trimming residues, used on soil restoration, on the properties of products obtained (organic matter, Kjeldahl-N, C/N ratio and nitrogen losses (N-losses)) in order to determine the best composting conditions. A second-order polynomial model consisting of four independent process variables was found to accurately describe (the differences between the experimental values and those estimated by using the equations never exceeded 10% of the former) the composting process. Results of the experiment showed that compost with acceptably chemical properties (OM, 85%; Kjeldahl-N, 3.2%), high degradation and minimum N-losses entails operating at high operation time (78 days), low particle size (1cm), medium moisture content (40%) and medium to low aeration level (0.2-0.4 l air/min kg).
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Conservación de los Recursos Naturales , Nitrógeno/metabolismo , Suelo , Reactores Biológicos , Carbono , Compuestos Orgánicos/metabolismo , Tamaño de la Partícula , Temperatura , Factores de TiempoRESUMEN
This paper will consider the influence of the temperature of autohydrolysis or hydrothermal process from Paulownia fortunei L. to obtain a valuable liquid phase and a suitable solid phase to produce pulp. The solid phase resulting of autohydrolysis was subjected to organosolv pulping process and formed paper sheets, analyzing the influence of operational variables (viz., ethanol concentration, temperature and pulping time) on the yield, viscosity, tensile index, burst index, tear index and brightness. Maximum glucose and xylose contents and minimum paper sheets characteristic loss have been obtained at 190 degrees C authohydrolysis temperature. Suitable characteristics of paper sheets and acceptable yield, viscosity and kappa number of pulp could be obtained by operating at 180 degrees C temperature, 30min pulping time and 20% ethanol concentration. Under those conditions sheets paper with 27.4% ISO brightness, 28.87Nm/g tensile index, 1.22kPam(2)/g burst index and 1.23kNm(2)/g tear index could be obtained.
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Etanol/química , Magnoliopsida/química , Papel , Solventes/química , Madera/química , Calor , Hidrólisis , Madera/análisisRESUMEN
In order to identify faster-growing non-woody species usable for biomass and paper production, four Leucaena species (L.diversifolia, L. colinsii, L. salvadorensis and three varieties of L. leucocephala) were tested. All the Leucaena species showed a good soil and climatic adaptation to Spain Southwest except for L. salvadorensis. Studied Leucaena species showed biomass productivity ranges from 67.14 to 9.44 t ha(-1) (o.d.b.) and 43.6 to 11.4 t ha(-1) under Mediterranean conditions for the first and second year sprouts, respectively. The quantity of solubles and extractives shows similar values when compared with wood materials. Relatively lower lignin content in Leucaena (from 15.7% to 21.4%) species has been found with respect to other vegetal species. The alpha-cellulose contents (39.4-45.3%) are in the range of the normal values expected for the other non-wood raw materials. The study confirms the feasibility of organocell yield pulping process to Leucaena species. Organocell process provides an efficient delignification (kappa number 12.4 and pulp yield 42.2%) for L. leucocephala and suitably physical characteristics of paper sheet (tensile index 20.3 kNm/kg for L. diversifolia).
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Biomasa , Fabaceae/metabolismo , Papel , Celulosa/metabolismoRESUMEN
The toxicokinetics of lambda-cyhalothrin after single 20 mg kg(-1) oral and 3 mg kg(-1) intravenous doses were studied in rats. Serial blood samples were obtained after oral and intravenous administration. Liver, brain, spinal cord, sciatic nerve, vas deferens, anococcygeus and myenteric plexus tissue samples were also collected. Plasma, liver, hypothalamus, cerebellum, medulla oblongata, frontal cortex, striatum, hippocampus, midbrain, spinal cord, vas deferens, anococcygeus, myenteric plexus and sciatic nerve concentrations of lambda-cyhalothrin were determined by HPLC. The plasma and tissue concentration-time data for lambda-cyhalothrin were found to fit a two-compartment open model. For lambda-cyhalothrin, the elimination half-life (T1/2beta) and the mean residence time from plasma were 7.55 and 8.55 h after i.v. and 10.27 and 14.43 h after oral administration. The total plasma clearance was not influenced by dose concentration or route and reached a value of 0.060l h(-1)kg(-1). After i.v. administration, the apparent volume of distribution and at steady state were 0.68 and 0.53l kg(-1), suggesting a diffusion of the pyrethroid into tissue. After oral administration, lambda-cyhalothrin was extensively but slowly absorbed (Tmax, 2.69 h). The oral bioavailability was found to be 67.37%. Significant differences in the kinetic parameters between nervous tissues and plasma was observed. The maximum concentrations in hypothalamus (Cmax, 24.12 microg g(-1)) and myenteric plexus (Cmax, 25.12 microg g(-1)) were about 1.5 times higher than in plasma (Cmax, 15.65 microg ml(-1)) and 1.3 times higher than in liver (Cmax, 18.42 microg ml(-1)). Nervous tissue accumulation of lambda-cyhalothrin was also reflected by the area under the concentration curve ratios of tissue/plasma (liver). The T1/2beta for lambda-cyhalothrin was significantly greater for the nerve tissues, including neuromuscular fibres, (range 12-26 and 15-34 h, after i.v. and oral doses) than for plasma (7.55 and 10.27 h, respectively).