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1.
Artículo en Inglés | MEDLINE | ID: mdl-38485560

RESUMEN

INTRODUCTION AND AIMS: Gastric adenocarcinoma is among the high-ranking tumors, with respect to frequency and mortality, worldwide. The inflammatory process and immune system activity are associated with oncologic control. Our aim was to identify whether the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and other variables are prognostic factors for survival in patients with metastatic gastric cancer in a Mexican population. MATERIAL AND METHODS: Patients diagnosed with metastatic gastric adenocarcinoma, hospitalized within the time frame of December 2011 to 2021, were analyzed. The NLR, PLR, and albumin and hemoglobin levels obtained from blood samples were calculated. Functional status (ECOG and Karnofsky), sex, histology, and the presence of signet ring cells were also considered possible prognostic factors. Each factor's prognostic value for overall survival was determined through univariate and multivariate analyses. RESULTS: The study included 956 patients diagnosed with metastatic gastric cancer, of whom 494 (51.7%) were men and 462 (48.3%) were women. The main histologic finding was diffuse adenocarcinoma (n = 619, 64.7%), followed by intestinal adenocarcinoma (n = 293, 30.6%), and the presence of signet ring cells was found in 659 (68.9%) patients. Diagnostic laparoscopy was performed on 238 patients (24.9%) to confirm peritoneal carcinomatosis. The multivariate analysis showed that an NLR above 3.2 (HR 1.51, 95% CI 1.27-1.8; p < 0.001), albumin below 3.5 g/dl (HR 1.25, CI 1.06-1.47; p = 0.006), and an ECOG performance status of 2 or higher (HR 1.39, CI 1.10-1.76; p = 0.005) were independent factors that predicted a lower survival rate, whereas a Karnofsky score above 70% (HR 0.69, CI 0.53-0.91; p = 0.008) was associated with a better survival rate. Lastly, the PLR was not statistically significant in the multivariate analysis. CONCLUSIONS: The NLR, nutritional status assessed through albumin measurement, and functional status can act as independent prognostic survival factors in hospitalized Mexican patients diagnosed with metastatic gastric adenocarcinoma and be taken into account during therapeutic decision-making.

2.
Clin Kidney J ; 17(1): sfad306, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38250251

RESUMEN

Background: Recent studies showed a high prevalence of monoclonal gammopathy (MG) in patients with thrombotic microangiopathy (TMA) aged over 50 years and suggested that complement dysregulation is pivotal for the disease to develop. Here, we studied this premise in seven patients with TMA and coexisting MG. Methods: Patients with TMA on kidney biopsy and/or peripheral blood were recruited from the prospective COMPETE cohort (NCT04745195) and Limburg Renal Registry. Patients were screened for complement dysregulation, including genetics/factor H autoantibodies (FHAA) and functional ex vivo testing on microvascular endothelial cells. Results: Seven (8%) out of 84 patients with TMA presented with a coexisting MG. MG clustered in patients aged over 50 years (n/N = 6/32, 19%). C4 and/or C3 levels were low in three patients, while four patients presented with normal complement levels. None of the patients carried rare variants in complement genes. Massive ex vivo C5b9 formation on the endothelium was noted in one patient; purified IgG from this patient caused massive ex vivo C5b9 formation via the alternative pathway of complement activation, pointing to complement dysregulation in the fluid phase. Kidney biopsies from other nephropathies linked to MG rarely exhibited concurrent TMA (n/N = 1/27, 4%). Conclusions: MG clustered in patients with TMA aged over 50 years. TMA and coexisting MG represents a heterogeneous disease spectrum, including a small subset of patients who may present with complement dysregulation.

3.
Br J Cancer ; 129(5): 838-851, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37464024

RESUMEN

BACKGROUND: Occupational exposures constitute the second leading cause of urinary bladder cancer after tobacco smoking. Increased risks have been found in the petroleum industry, but high-quality exposure data are needed to explain these observations. METHODS: Using a prospective case-cohort design, we analysed 189 bladder cancer cases (1999-2017) and 2065 randomly drawn non-cases from the Norwegian Offshore Petroleum Workers cohort. Cases were identified in the Cancer Registry of Norway, while work histories (1965-1998) and lifestyle factors were recorded by questionnaire at baseline (1998). Occupational petroleum-related hydrocarbon exposures were assessed by expert-developed job-exposure matrices. Hazard ratios were estimated by weighted Cox-regressions, adjusted for age, tobacco smoking, education, and year of first employment, and with lagged exposures. RESULTS: Increased risks were found in benzene-exposed workers, either long-term exposure (≥18.8 years, HR = 1.89, 95% CI: 1.14-3.13; p-trend = 0.044) or high-level cumulative benzene exposure (HR = 1.60, 95% CI: 0.97-2.63; p-trend = 0.065), compared with the unexposed. Associations persisted with 20-year exposure lag. No associations were found with skin or inhalation exposure to crude oil, mineral oil (lubrication, hydraulics, turbines, drilling), or diesel exhaust. CONCLUSIONS: The results suggest that exposures in the benzene fraction of the petroleum stream may be associated with increased bladder cancer risk.


Asunto(s)
Enfermedades Profesionales , Exposición Profesional , Petróleo , Neoplasias de la Vejiga Urinaria , Humanos , Masculino , Benceno/toxicidad , Petróleo/efectos adversos , Hidrocarburos/efectos adversos , Exposición Profesional/efectos adversos , Neoplasias de la Vejiga Urinaria/inducido químicamente , Neoplasias de la Vejiga Urinaria/epidemiología , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/epidemiología
5.
Int J Epidemiol ; 52(4): 1003-1014, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-36548214

RESUMEN

BACKGROUND: Night shift work may acutely disrupt the circadian rhythm, with possible carcinogenic effects. Prostate cancer has few established risk factors though night shift work, a probable human carcinogen, may increase the risk. We aimed to study the association between night shift work and chlorinated degreasing agents (CDAs) as possible endocrine disrupters in relation to aggressive prostate cancer as verified malignancies. METHODS: We conducted a case-cohort study on 299 aggressive prostate cancer cases and 2056 randomly drawn non-cases in the Norwegian Offshore Petroleum Workers cohort (1965-98) with linkage to the Cancer Registry of Norway (1953-2019). Work history was recorded as years with day, night, and rollover (rotating) shift work, and CDA exposure was assessed with expert-made job-exposure matrices. Weighted Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for aggressive prostate cancer, adjusted for education and year of first employment, stratified by 10-year birth cohorts, and with 10, 15, and 20 years of exposure lag periods. RESULTS: Compared with day work only, an increased hazard of aggressive prostate cancer (HR = 1.86, 95% CI 1.18-2.91; P-trend = 0.046) was found in workers exposed to ≥19.5 years of rollover shift work. This persisted with longer lag periods (HR = 1.90, 95% CI 0.92-3.95; P-trend = 0.007). The exposure-hazard curve for a non-linear model increased linearly (HRs ≥1.00) for 18-26 years of rollover shift work. No association was found with CDA exposure. CONCLUSIONS: Long-term exposure to rollover shift work may increase the hazard of aggressive prostate cancer in offshore petroleum workers.


Asunto(s)
Petróleo , Neoplasias de la Próstata , Horario de Trabajo por Turnos , Masculino , Humanos , Horario de Trabajo por Turnos/efectos adversos , Estudios de Cohortes , Petróleo/efectos adversos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/etiología , Factores de Riesgo , Noruega/epidemiología
6.
Int J Epidemiol ; 52(3): 887-898, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-36413027

RESUMEN

BACKGROUND: Most antihypertensives can induce dermal photosensitivity, which may increase melanoma risk. However, corroborating evidence is limited. We examined the associations between use of antihypertensives and melanoma risk. METHODS: A nationwide nested case-control study was conducted using data from the Cancer Registry of Norway, the National Registry and the Norwegian Prescription Database in 2004-15. Ten controls were randomly selected for each melanoma case, matched on sex and birth year. The study included 12 048 cases and 117 895 controls. We estimated rate ratios (RRs) with 95% confidence intervals (CIs). All analyses were adjusted for ambient ultraviolet radiation (UVR). We additionally performed active comparator analyses, and sensitivity analyses by only including new users, distinguishing between exclusive and mixed users, allowing for different latency periods, and subgroup analyses by melanoma subtype and clinical stage. RESULTS: Compared with non-use, we observed a slightly increased melanoma risk in users of diuretics (RR 1.08, CI 1.01-1.15), calcium-channel blockers (RR 1.10, CI 1.04-1.18) and drugs affecting the renin-angiotensin system (RR 1.10, CI 1.04-1.16), but not for beta blockers (RR 0.97, CI 0.92-1.03). We found no heterogeneity of associations by melanoma subtype or clinical stage and no dose-response relationship between the cumulative defined daily doses (DDDs) and melanoma. No interaction was found between cumulative DDDs and ambient UVR. CONCLUSIONS: Weak associations, with lack of a dose-response relationship and lack of interactions with ambient UVR, in the DDD analysis in this nationwide study do not support a causal relationship between antihypertensives and melanoma risk.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Antihipertensivos/efectos adversos , Melanoma/epidemiología , Neoplasias Cutáneas/epidemiología , Estudios de Casos y Controles , Rayos Ultravioleta , Melanoma Cutáneo Maligno
9.
Brain Inj ; 35(9): 1043-1053, 2021 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-34357825

RESUMEN

PRIMARY OBJECTIVE: The aim of the study was twofold. First, to study the relationship among apathy in the long term, initial clinical measures, and standard outcome scores after traumatic brain injury (TBI). Second, to describe white matter integrity correlates of apathy symptoms. RESEARCH DESIGN: Correlational study. Methods and Procedures: Correlation and Bayesian networks analyses were performed in a sample of 40 patients with moderate to severe TBI in order to identify the relationship among clinical variables, functionality, and apathy. A diffusion tensor imaging study was developed in 25 participants to describe correlations between fractional anisotropy (FA) measures and apathetic symptoms. MAIN OUTCOMES AND RESULTS: Correlation analysis revealed associations between pairs of variables as apathy in the long term and functional score at discharge from hospital. Bayesian network illustrated the relevant role of axonal injury mediating the relationship between apathy and initial clinical variables. FA in the superior longitudinal fasciculus, the inferior longitudinal fasciculus, and the internal capsule were negatively correlated with apathy measures. Widespread brain areas showed positive correlations between FA and apathy. CONCLUSIONS: These results highlight the relevance of white matter integrity measures in initial assessment after TBI and its relationship with apathetic manifestations in the chronic phase.


Asunto(s)
Apatía , Lesiones Traumáticas del Encéfalo , Sustancia Blanca , Anisotropía , Teorema de Bayes , Encéfalo , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora , Humanos , Sustancia Blanca/diagnóstico por imagen
11.
Trauma (Majadahonda) ; 25(3): 121-126, jul.-sept. 2014. tab, ilus
Artículo en Español | IBECS | ID: ibc-128352

RESUMEN

Objetivo: Establecer la relevancia clínica de la presencia de infiltrados de células inflamatorias evidenciables histológicamente en muestras de hernias de disco lumbares operadas. Material y método: Se obtuvieron muestras de discos lumbares de 50 pacientes operados de forma consecutiva durante el año 2012. Se recogieron los datos clínicos y epidemiológicos de los pacientes antes de la cirugía, el tiempo de evolución de los síntomas, así como la presencia de radiculopatía, déficits neurológicos y la exploración. Se estableció el carácter extruido o contenido de la hernia en RM. Se estableció la presencia y cuantía de celularidad condrocitaria como signo de degeneración discal. Resultados: Aunque casi todos las muestras reflejaban proliferación condrocitaria, la presencia de infiltrados inflamatorios o neovascularización fue escasa. La presencia de inflamación se relacionó invariablemente con la formación de nuevos vasos en el disco, no relacionándose con ninguna variable clínica o radiológica. Conclusión: No hay relación entre la presencia de infiltrados inflamatorios y los datos clínicos registrados. La presencia de infiltrados inflamatorios en el interior del disco herniado no tiene relación ni con la degeneración discal ni con la producción de clínica dolorosa (AU)


Objective: To establish the clinical relevance of the histological evidence of inflammatory cell infiltrates in surgical samples of operated lumbar disc hernia. Material and method: Surgical samples, clinical, and epidemiological data were obtained from 50 patients consecutively operated on of lumbar disc herniation during 2012 were obtained. Also the MR appearance as extruded or contained hernia was recorded. All samples were processed using hematoxilin-eosin staining and different histological parameters were determined such as the presence and quantity of chondrocytes present in the disc as a sign of disc degeneration. Results: Even though the majority of samples examined showed signs of disc degeneration, such as the presence of chondrocyte proliferation, the evidence of neovascularisation or inflammatory infiltrates was scarce. The presence of inflammatory infiltrates was invariably related to the presence of neovascularisation. However, the presence of inflammatory infiltrates was not related to any radiological or clinical variable. Conclusion: There is no relation between the presence of inflammatory infiltrates and the clinical data registered. The presence of histological evidence of inflammation in herniated lumbar disc tissue is not related to disc degeneration or the presence of pain (AU)


Asunto(s)
Humanos , Masculino , Femenino , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/diagnóstico , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/fisiopatología , Desplazamiento del Disco Intervertebral , Inflamación/complicaciones , Inflamación/diagnóstico , Inflamación/terapia , Estudios Prospectivos , Laminectomía/métodos , Inmunohistoquímica
12.
AJNR Am J Neuroradiol ; 35(5): 1029-34, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24335539

RESUMEN

BACKGROUND AND PURPOSE: In patients with spinal cord injury after blunt trauma, several studies have observed a correlation between neurologic impairment and radiologic findings. Few studies have been performed to correlate spinal cord injury with ligamentous injury. The purpose of this study was to retrospectively evaluate whether ligamentous injury or disk disruption after spinal cord injury correlates with lesion length. MATERIALS AND METHODS: We retrospectively reviewed 108 patients diagnosed with traumatic spinal cord injury after cervical trauma between 1990-2011. Plain films, CT, and MR imaging were performed on patients and then reviewed for this study. MR imaging was performed within 96 hours after cervical trauma for all patients. Data regarding ligamentous injury, disk injury, and the extent of the spinal cord injury were collected from an adequate number of MR images. We evaluated anterior longitudinal ligaments, posterior longitudinal ligaments, and the ligamentum flavum. Length of lesion, disk disruption, and ligamentous injury association, as well as the extent of the spinal cord injury were statistically assessed by means of univariate analysis, with the use of nonparametric tests and multivariate analysis along with linear regression. RESULTS: There were significant differences in lesion length on T2-weighted images for anterior longitudinal ligaments, posterior longitudinal ligaments, and ligamentum flavum in the univariate analysis; however, when this was adjusted by age, level of injury, sex, and disruption of the soft tissue evaluated (disk, anterior longitudinal ligaments, posterior longitudinal ligaments, and ligamentum flavum) in a multivariable analysis, only ligamentum flavum showed a statistically significant association with lesion length. Furthermore, the number of ligaments affected had a positive correlation with the extension of the lesion. CONCLUSIONS: In cervical spine trauma, a specific pattern of ligamentous injury correlates with the length of the spinal cord lesion in MR imaging studies. Ligamentous injury detected by MR imaging is not a dynamic finding; thus it proved to be useful in predicting neurologic outcome in patients for whom the MR imaging examination was delayed.


Asunto(s)
Vértebras Cervicales/lesiones , Ligamentos/lesiones , Traumatismos de los Tejidos Blandos/etiología , Traumatismos de la Médula Espinal/etiología , Fracturas de la Columna Vertebral/complicaciones , Heridas no Penetrantes/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/patología , Femenino , Humanos , Ligamentos/diagnóstico por imagen , Ligamentos/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Traumatismos de los Tejidos Blandos/diagnóstico , Traumatismos de la Médula Espinal/diagnóstico , Fracturas de la Columna Vertebral/diagnóstico , Estadística como Asunto , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/diagnóstico , Adulto Joven
13.
J Environ Manage ; 125: 117-25, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23651918

RESUMEN

When producing activated carbons from agricultural by-products, certain properties, such as yield and specific surface area, are very important for obtaining an economical and promising adsorbent material. Nevertheless, many researchers have not simultaneously optimized these properties and have obtained different optimal conditions for the production of activated carbon that either increases specific surface area but decreases yield or vice versa. In this research, the production of activated carbon from barley husks (BH) by chemical activation with zinc chloride was optimized by using a 2(3) factorial design with replicates at the central point, followed by a central composite design with two responses (the yield and iodine number) and three factors (the activation temperature, activation time, and impregnation ratio). Both responses were simultaneously optimized by using the desirability functions approach to determine the optimal conditions of this process. The findings reveal that after the simultaneous dual optimization, the maximal response values were obtained at an activation temperature of 436 °C, an activation time of 20 min, and an impregnation ratio of 1.1 g ZnCl2/g BH, although the results after the single optimization of each response were quite different. At these conditions, the predicted values for the iodine number and yield were 829.58 ± 78.30 mg/g and 46.82 ± 2.64%, respectively, whereas experimental tests produced values of 901.86 mg/g and 48.48%, respectively. Moreover, activated carbons from BH obtained at the optimal conditions primarily developed a porous structure (mesopores > 71% and micropores > 28%), achieving a high surface area (811.44 m(2)/g) that is similar to commercial activated carbons and lignocellulosic-based activated carbons. These results imply that the pore width and surface area are large enough to allow the diffusion and adsorption of pollutants inside the adsorbent particles. In summary, two responses were optimized to determine the optimal conditions for the production of activated carbons because it is possible to increase both the specific surface area and yield.


Asunto(s)
Carbón Orgánico , Hordeum , Cloruros/química , Yodo/química , Compuestos de Zinc/química
14.
Food Chem ; 138(1): 564-73, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23265525

RESUMEN

Broccoli (Brassica oleracea var. italica) is a vegetable that requires the application of postharvest techniques to extend its marketability. Controlled atmosphere and 1-MCP treatments are most used to extend the shelf life of broccoli and reduce post-harvest deterioration. The aim of this study was to evaluate the visual, physicochemical and functional changes of broccoli head samples stored at 1-2 °C and 85-90% relative humidity (RH) in air (Control samples), under controlled atmospheres (10% O(2) and 5% CO(2)) (CA samples) and treated with 1-MCP (0.6 µL/L). After storage all samples were maintained at 20 °C for 2 and 4 days, in order to assess their shelf life. The most suitable postharvest treatment to extend broccoli quality during storage and shelf life, in terms of maintaining the visual quality and reducing loss of health-promoting compounds, was achieved by storage under controlled atmosphere conditions. The use of 1-MCP reduced the loss of green colour and chlorophyll pigments, but only during cold storage not during shelf life at 20 °C.


Asunto(s)
Brassica/química , Brassica/efectos de los fármacos , Ciclopropanos/farmacología , Conservación de Alimentos/métodos , Atmósfera , Brassica/crecimiento & desarrollo , Almacenamiento de Alimentos , Humedad , Extractos Vegetales/análisis
15.
Acta Anaesthesiol Scand ; 56(8): 1032-41, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22834710

RESUMEN

BACKGROUND: This study describes the design of a hypnosis closed-loop control system with propofol. The controller used a proportional-integral (PI) algorithm with the bispectral index (BIS) as the feedback signal. Our hypothesis was that a PI closed-loop control could be applied in clinical practice safely keeping the BIS within a pre-determined target range. METHODS: The adjustment of the PI parameters was based on simulation. The procedure had three steps: obtaining a patient model using data from 12 patients, designing and adjusting the controller in simulation, and fine tuning the PI parameters in a pilot study (10 patients). The resulting controller was tested in 24 American Society of Anesthesiology (ASA) I-II patients. The controller directly decides the infusion rate of propofol, and no model is necessary in its online operation. The BIS target was set to 50. Remifentanil was used for analgesia. RESULTS: We evaluated the efficiency and safety of the automatic feedback system. It worked properly in all the patients. The median performance error was -1.62, and the median absolute performance error was 11.03. Average propofol-normalized consumption was 5.3 ± 1.8 mg/kg/h. Mean percentage of BIS in the range 40-60 was 83%. Mean time to open eyes was 8 ± 4 min. Time to extubation was 9 ± 5 min. Hemodynamic adverse event or intraoperative awareness were not recorded. CONCLUSIONS: The closed-loop system was able to maintain the BIS within an acceptable range of levels. The control of a propofol infusion guided by the BIS is feasible without hemodynamic instability in ASA I/II patients.


Asunto(s)
Anestesia Intravenosa/métodos , Monitores de Conciencia , Propofol/administración & dosificación , Abdomen/cirugía , Algoritmos , Anestésicos Intravenosos/administración & dosificación , Anestésicos Intravenosos/efectos adversos , Anestésicos Intravenosos/farmacocinética , Alarmas Clínicas , Simulación por Computador , Electroencefalografía , Diseño de Equipo , Femenino , Procedimientos Quirúrgicos Ginecológicos , Humanos , Infusiones Intravenosas , Despertar Intraoperatorio , Masculino , Persona de Mediana Edad , Modelos Teóricos , Proyectos Piloto , Propofol/efectos adversos , Propofol/farmacocinética , Programas Informáticos
16.
Br J Sports Med ; 46(12): 854-60, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22522586

RESUMEN

Ankle injuries are a huge medical and socioeconomic problem. Many people have a traumatic injury of the ankle, most of which are a result of sports. Total costs of treatment and work absenteeism due to ankle injuries are high. The prevention of recurrences can result in large savings on medical costs. A multidisciplinary clinical practice guideline was developed with the aim to prevent further health impairment of patients with acute lateral ankle ligament injuries by giving recommendations with respect to improved diagnostic and therapeutic opportunities. The recommendations are based on evidence from published scientific research, which was extensively discussed by the guideline committee. This clinical guideline is helpful for healthcare providers who are involved in the management of patients with ankle injuries.


Asunto(s)
Traumatismos del Tobillo/prevención & control , Traumatismos en Atletas/prevención & control , Esguinces y Distensiones/prevención & control , Traumatismos del Tobillo/diagnóstico , Traumatismos del Tobillo/terapia , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/terapia , Tirantes , Medicina Basada en la Evidencia , Terapia por Ejercicio/métodos , Personal de Salud , Humanos , Hipotermia Inducida/métodos , Hielo , Inmovilización/métodos , Relaciones Interprofesionales , Ligamentos Articulares/lesiones , Modalidades de Fisioterapia , Guías de Práctica Clínica como Asunto , Pronóstico , Rehabilitación Vocacional/métodos , Factores de Riesgo , Esguinces y Distensiones/diagnóstico , Esguinces y Distensiones/terapia , Cinta Quirúrgica
17.
J Environ Manage ; 95 Suppl: S77-82, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21292385

RESUMEN

An experimental design methodology was applied to study the effects of temperature, pH, biomass dose, and stirring speed on copper removal from aqueous solutions by Aspergillus terreus in a biosorption batch system. To identify the effects of the main factors and their interactions on copper removal efficiency and to optimize the process, a full 2(4) factorial design with central points was performed. Four factors were studied at two levels, including stirring speed (50-150 min(-1)), temperature (30-50°C), pH (4-6) and biosorbent dose (0.01-0.175 g). The main factors observed were pH and biomass dose, along with the interactions between pH and biomass, and stirring speed. The optimal operational conditions were obtained using a response surface methodology. The adequacy of the proposed model at 99% confidence level was confirmed by its high adjusted linear coefficient of determination (R(Adj)(2)=0.9452). The best conditions for copper biosorption in the present study were: pH 6, biosorbent dose of 0.175 g, stirring speed of 50 min(-1) and temperature of 50°C. Under these conditions, the maximum predicted copper removal efficiency was 68.52% (adsorption capacity of 15.24 mg/g). The difference between the experimental and predicted copper removal efficiency at the optimal conditions was 4.8%, which implies that the model represented very well the experimental data.


Asunto(s)
Aspergillus/metabolismo , Cobre/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Biomasa , Concentración de Iones de Hidrógeno , Microbiología Industrial/métodos , Modelos Teóricos , Soluciones/química , Temperatura
20.
Eval Program Plann ; 22(2): 141-53, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-24011409

RESUMEN

This article reports the program evaluation findings of a male juvenile halfway house. An analysis of three program aspects is provided: (a) program components, (b) a review of closed resident records, and (c) Department of Juvenile Justice program indicators. Using 101 cases, a juvenile offender descriptive profile is presented as an important ingredient for interpreting program needs and focus. Using existing literature, the program is compared to other similar juvenile halfway houses. Recommendations are made for future practice and program evaluation in this area.

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