Artículos Científicos

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Uso de la distribución lévy para ajustar datos con marcada asimetría y valores extremos
(Universidad de La Habana, 202-01-31) Martínez Naranjo, Jessica Lizeth; Alvear Rodríguez, Carlos Armando; Tovar Cueva, José Rafael
Con el fin de proponer una metodología estadística que permita modelar datos asimétricos usando la distribución Levy, se presenta un estudio de simulación bajo nueve escenarios diferentes para evaluar la estimación de los parámetros de la distribución en los dos enfoques de la estadística (Clásica y Bayesiana). Se consideraron las distribuciones de probabilidad Log-Normal, Levy y Levy Estándar para modelar el comportamiento de dos conjuntos de datos reales con asimetría positiva, encontrando que la distribución Levy ajusto bien al conjunto de datos propuesto, por lo tanto, se puede considerar la distribución Levy como candidata para ajustar datos asimétricos con presencia de valores extremos.
Cryptococcus neoformans en excretas de palomas del perímetro urbano de Cali
(Colombia Medica, 1996) Caicedo B, Luz Dary; Alvarez Valle, María Inés; Elisa Llanos, Carmen; Molina, Dazuly
En el perímetro urbano de Santiago de Cali, Colombia, se realizó un estudio con excretas de palomas, con el fin de establecer la presencia de Cryptococcus neoformans; para aislar el hongo se utilizó agar semilla de girasol. Se analizó si la presencia del hongo se relacionaba con factores como la cantidad de excretas, el tipo de nido, el número de palomas y el pH. De 119 muestras, 59 (49.6%) presentaron la levadura. Todos los aislamientos correspondieron a C. neoformans var neoformans. Se estableció que la levadura tiene una amplia distribución en la ciudad y que hay mayor probabilidad de encontrarla en excretas acumuladas (p < 0.0001). Los lugares de nidos más frecuentes fueron cajas de madera y cielos rasos; en estos últimos se recuperó el hongo en todas las muestras examinadas. Fue significante la asociación entre el aislamiento y el sistema de nidación (p < 0.05). Se determinó que un número mayor de 15 palomas influye significativamente en el aislamiento del hongo (p < 0.0039). El pH no mostró relación estadísticamente significativa. Este trabajo subraya la importancia de emprender campañas que eviten la acumulación de excretas de palomas.
Cryptococcus neoformans in bird excreta in the city zoo of Cali, Colombia
(Mycopathologia, 1999-12) Caicedo, Luz Dary; Alvarez, María Inés; Delgado, Maritza; Cárdenas, Alaín
The presence of Cryptococcus neoformans was studied in bird excreta and in the air circulating in and around bird cages in the City Zoo of Cali, Colombia, between August 1994 and April 1995, using a sunflower seed agar culture medium for fungus isolation. A total of 380 samples was studied, 110 from droppings and 270 from Petri dishes placed inside(148) and outside (122) the cages. C. neoformansvar neoformans was found in only two cases, one from bird excreta (0.9%) and the other from air inside a cage (0.7%). The former positive sample was collected from the cracks of a dead tree where two crested caracaras (Polyborusplancus) roosted; the feces were dry, accumulated,and with a pH of 6. The other positive sample was found inside the cage of these birds; however, samples taken in a dispersion study at 0.5, 1, 5 and 10 m around this cage were all negative. It appears that this low isolation rate is due to adequate cleaning and disinfection procedures used in the city zoo of Cali.
La lectura interpretativa del antibiograma: Una herramienta para predecir la resistencia bacteriana en el laboratorio de microbiología de rutina
(Colombia Medica, 2002) Crespo, María del Pilar
La aparición cada vez más frecuente y diversa de los mecanismos de resistencia a nivel microbiano y sobre todo en aquellas bacterias patógenas facultativas e incluso oportunistas, ha traído consecuencias importantes en términos de morbilidad y mortalidad y millonarias pérdidas no sólo humanas sino económicas. El impacto de la diseminación de estas cepas escapa a los cálculos establecidos y en la mayoría de los casos no se ha dado la relevancia real y pertinente al problema que se afronta. Como es tal vez menos complicado evitar que tratar en este caso específico, es de suma importancia poder reconocer, descubrir, tratar eficazmente y prevenir las infecciones por microorganismos resistentes. Esta revisión tiene como objeto profundizar en el cómo y para qué de una herramienta que puede utilizarse para este efecto en el laboratorio de microbiología de rutina: “la lectura interpretativa del antibiograma”. Esta puede ser aplicada en las bacterias más frecuentes y constituye una herramienta sencilla y accesible que permite hacer inferencias sobre los mecanismos de resistencia más estudiados. Lo anterior representa un importante aporte para un mejor y mayor enfoque en el tratamiento antibiótico del paciente infectado con estas cepas y a la vez suministra un control de calidad al informe y diagnóstico microbiológico.
Onychomycosis in Cali, Colombia
(Mycopathologia, 2004-07) Alvarez, María Inés; González, Luz Ángela; Castro, Luz Ángela
This study presents the epidemiological and mycological aspects of 299 patients with nail lesions who were referred to three diagnostic laboratories in the city of Cali. The diagnosis of mycoses was established through visualization of mycotic structures in a direct microscopic examination of skin scrapings and by isolation. Onychomycosis was found in 183 cases (61.2%), of which 141 were in toenails (44 in males and 97 in females), 38 in fingernails (9 males and 29 females), and 4 cases in toenails and fingernails simultaneously (all females). No statistically significant relation was found between sex and onychomycosis. Yeasts accounted for 40.7% of the mycoses, dermatophytes for 38%, nondermatophyte molds for 14% and the etiology was mixed in the remaining cases (7.3%). Candida albicans was the most commonly isolated yeast species; the most common dermatophyte was Trichophyton rubrum and Fusarium spp. and Scytalidium dimidiatum were the most common nondermatophytic molds. Them common fungi found in fingernails were yeasts; in toenails dermatophytes were more prevalent (χ2 with Yates' correction = 19.75, P = 0.000088). Yeasts were observed more frequently in females while dermatophytes were more common in males. The difference between these two etiologic groups was statistically significant (χ2 with Yates' correction = 7.43, P = 0.0064); no relation was observed according to age.
Sexual function, menopause and hormone replacement therapy (HRT)
(Maturitas, 2004-08-20) González, Marcela; Viáfara, Gloria; Caba, Fresia; Molina, Esteban
Objective: To assess the prevalence of female sexual dysfunction in premenopausal and postmenopausal women with and without hormone replacement therapy (HRT). To determine the relationship between menopause and sexual activity, and the impact of HRT on sexual function. Methods: A cross-sectional analysis of 231 Colombian-born women, aged 40–62 years. Sexual function was measured by self-questionnaire. The analysis was performed by using the χ 2-test and multivariate regression analysis. The sexual function was divided in five domains: desire, arousal, lubrication, orgasm and pain; in addition, questioning about sexual satisfaction was included in the research. Results: In the study 38.1% of women showed sexual dysfunction in the desire, and 25% in the arousal, these two being the most affected domains. Even though menopause marginally decreases all stages of sexual function, this association was statistically significant only for the lubrication and pain domains. HRT improves sexual function in the orgasm, lubrication and pain domains in a statistically significant manner. The level of sexual satisfaction was better on postmenopausal women with HRT than ones without HRT. Age negatively influences almost all sexual function domains in a significant manner. Conclusions: Menopause affects in a negative manner some domains of female sexual function. HRT improves some factors of the sexual function during menopause but it not improves desire and arousal which were the most affected domains. There is a negative association between age and female sexual response in middle-aged women.
Application of a model established on a basis of love with pregnant teenagers at the healthcare Center Centro de Salud Cristóbal Colón, Cali, Colombia
(Colombia Medica, 2005) Montes, Marlene; Argote, Luz Ángela; Alvarez, Gloria Cielo; Osorio, Asceneth; Osorio, Olga
Introducción: Este estudio se hizo para aplicar un modelo teórico, cuyo concepto central es el amor y sus componentes; y los subconceptos la sensibilidad, la percepción, la interacción y la comunicación a fin de vislumbrar nuevos alcances en las prácticas de salud, que se relacionan con el cuidado de la adolescente, qué significa la gravidez para ella, su familia y el equipo de salud a partir del amor a sí misma y a los otros. Metodología: El estudio se efectuó con un enfoque cualitativo y de investigación. Las adolescentes, con edades entre 14 y 19 años, y previo consentimiento informado, se seleccionaron a partir del cuarto mes de gestación. Se obtuvieron datos sobre aspectos sociodemográficos, factores de riesgo y protectores y medición de la escala de autoestima de Janda. Se aplicó el modelo a través de talleres en los que participaron las adolescentes, los agentes de salud del área de influencia y se analizó su impacto mediante entrevistas en profundidad. Resultados: Los hallazgos confirman los factores de riesgo y protectores propios de las adolescentes en este nivel socio económico; hubo aumento en los valores en la escala de autoestima con respecto a la medición inicial. Las entrevistas en profundidad revelaron cinco categorías relacionadas con el proceso de embarazo vivido por las adolescentes: búsqueda de identidad, expectativas familiares y sociales interrumpidas, amor y desamor en las relaciones interpersonales, influencia de la figura femenina en las decisiones, y el desafío amoroso como rescate de autoestima y expresión de sentimientos. Conclusión: El desarrollo de los talleres permitió fortalecer en los agentes de salud y en las adolescentes grávidas, por medio de la sensibilización y reflexión de los temas tratados, aplicar los conceptos que plantea el modelo del desafío amoroso. Con este proyecto se rescató el arte de asistir/cuidar/enseñar/investigar a través de la búsqueda de nuevos caminos, a las adolescentes grávidas, y transformar la enseñanza y la práctica de salud, cuando se considera a las personas en su contexto universal como seres totales.
Autoimmunity and molecular mimicry in tropical spastic paraparesis/human T-lymphotropic virus-associated myelopathy
(Associacao Brasileira de Divulgacao Cientifica, 2005-02-01)
Viruses share antigenic sites with normal host cell components, a phenomenon known as molecular mimicry. It has long been suggested that viral infections might trigger an autoimmune response by several mechanisms including molecular mimicry. More than 600 antiviral monoclonal antibodies generated against 11 different viruses have been reported to react with 3.5% of cells specific for uninfected mouse organs. The main pathological feature of tropical spastic paraparesis/human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (TSP/HAM) is a chronic inflammation of the spinal cord characterized by perivascular cuffing of mononuclear cells accompanied by parenchymal lymphocytic infiltration. We detected the presence of autoantibodies against a 98- to 100-kDa protein of in vitro cultured human astrocytes and a 33- to 35-kDa protein from normal human brain in the serum of HTLV-I-seropositive individuals. The two cell proteins exhibited molecular mimicry with HTLV-I gag and tax proteins in TSP/HAM patients, respectively. Furthermore, the location of 33- to 35-kDa protein cross-reaction correlated with the anatomical spinal cord areas (in the rat model) in which axonal damage has been reported in several cases of TSP/HAM patients. Our experimental evidence strongly suggests that the demyelinating process occurring in TSP/HAM may be mediated by molecular mimicry between domains of some viral proteins and normal cellular targets of the spinal cord sections involved in the neurodegeneration.
On the functional role of Arg172 in substrate binding and allosteric transition in Escherichia coli glucosamine-6-phosphate deaminase
(Archives of Biochemistry and Biophysics, 2005-10-01) Lucumí Moreno, Armando; Calcagno, Mario L.
Glucosamine-6-phosphate deaminase from Escherichia coli (EC 3.5.99.6) is an allosteric enzyme, activated by N-acetylglucosamine 6-phosphate, which converts glucosamine-6-phosphate into fructose 6-phosphate and ammonia. X-ray crystallographic structural models have showed that Arg172 and Lys208, together with the segment 41–44 of the main chain backbone, are involved in binding the substrate phospho group when the enzyme is in the R activated state. A set of mutants of the enzyme involving the targeted residues were constructed to analyze the role of Arg172 and Lys208 in deaminase allosteric function. The mutant enzymes were characterized by kinetic, chemical, and spectrometric methods, revealing conspicuous changes in their allosteric properties. The study of these mutants indicated that Arg172 which is located in the highly flexible motif 158–187 forming the active site lid has a specific role in binding the substrate to the enzyme in the T state. The possible role of this interaction in the conformational coupling of the active and the allosteric sites is discussed.
Prevalence of smoking habit in university students at Universidad Santiago de Cali
(Colombia Medica, 2006-04) Tafur, Luis Alberto; Ordóñez, Gustavo; Millán, Juan Carlos; Varela, Jesús María; Rebellón, Patricia
Introduction: It is important to study the smoking habit epidemiology in those of humans, which are in the process of academic formation. Those groups will be in the future agents of change in our community and in the case of people involved in the health areas; they are going to deal with risk factors related to chronic diseases. In 2004, the same questionnaire of other study carried out in 2003 was applied in students of programs operating during the day time and enrolled in the first semester, the questionnaire was done during the second half of the year; the purpose was to know the characteristics of the smoking habit in this population and to have a data base for future studies. Methods: This transversal study was done by applying a self responded questionnaire addressed to students of the day time journey and enrolled in the first semester from August to November of 2004. Results: The questionnaire was fulfilled by 1186 (89.6 %) out of 1324 students with criteria to be included in the study. A proportion of 23.2% of students were classified as smokers, with sporadic or habitual habit, and 4.4% of students were classified in the group of ex-smokers. There was a significant difference between males (34.2%) and females (18.2%). According to the group of age, those younger than 17 years old had the lowest proportion of smokers. Despite of non significant differences, the group older than 22 years old had the highest proportion of smokers. Comparing between academic programs, those students from social areas different to health had the highest rate of prevalence. Those students enrolled in programs related to the human airways had the lowest prevalence. Discussion: The prevalence of smokers in this group of study is similar to the rate reported in the general population and studies developed in university students. A bias of no response was confirmed in the study of 2003. Those students from academic programs related to the respiratory airways had lower rates of smokers, and this should be confirmed in other studies.
Knowledge of peri- postmenopause in Colombian women, a psychometric validation study
(Ciencia y Enfermeria, 2006-11-09) Triviño V, Zaider; Merino, José Manuel; Stiepovich Bertoni, Jasna
Aim: To validate knowledge scale of peri-postmenopause in Colombian women, from 45 to 60 years. Material and Methods: It is a nonexperimental design of observational type, which was realized in a quota sample comprised by 101 women of peri-postmenopause stage at Cali, Colombia, selected from representative sectors of low, middle and high socioeconomic strata, between June-August, 2006. The knowledge scale was constructed by 22 items, which included knowledges, beliefs, signs and symptoms and care; using questions of dichotomous format. Results: The total scale score, presented a relatively normal distribution, with an average of 15.8, and a standard deviation of 4.3, reliability was measured by means of Cronbach’s Alpha, which was 0.83. Principal component analysis showed an unidimensional structure, which explained 36 % of the variance. Face validity was obtained by using an expert’s committee. Conclusions: The scale of knowledge is reliable and valid in an application on Colombian peri-and postmenopause women. By means of principal components analysis scale unidimensionality was established.
Synthesis and characterization of Fe3AlC0.5 by mechanical alloying
(Hyperfine Interactions, 2006-12-07) Mercado, W. Barona; Fajardo, Marta; Pérez Alcázar, Germán Antonio; Sánchez Sthepa, H.
Double iron and aluminum carbides were prepared by mechanical alloying from elemental powders, with a ball-to-powder weight ratio 20:1. The samples were milled for 1, 3, 5, 10, 15, 20 and 25 h. The alloy progress for each milling time was evaluated by X-ray diffraction (XRD) and 57Fe Mössbauer spectroscopy. Once the alloy was consolidated two sorts of paramagnetic sites and a magnetic distribution were detected according to the Mössbauer fit. The majority doublet could correspond to Fe3AlC0.5 carbide as X-ray diffraction suggest, and the other could be Fe3AlC0.69; the magnetic distribution corresponding to Fe3Al phase, Fe7C3 and Fe5C2 single carbides. The hyperfine parameters are reported.
Acute and subacute toxicity of Salvia scutellarioides in mice and rats
(Journal of Ethnopharmacology, 2007-01-19) Ramírez, Jorge H.; Palacios, Mauricio; Tamayo, Oscar; Jaramillo, Roberto; Gutiérrez, Oscar
The acute and subacute toxicity of the aqueous extract of Salvia scutellarioides (Lamiaceae) was studied in mice and rats. In the acute toxicity test, oral administration of 2 g/kg of Salvia scutellarioides produced neither mortality nor changes in behavior or any other physiological activities. In subacute toxicity studies, no mortality was observed when the two doses of 1 or 2 g/kg day of aqueous extract of Salvia scutellarioides extract were administered orally for a period of 28 days. In the blood chemistry analysis, no significant changes occurred, including glucose, creatinine, blood urea nitrogen (BUN), aspartate transaminase (AST), alanine transaminase (ALT), potassium, sodium, chloride, calcium, phosphorus, conjugated billirrubin, total billirrubin, total cholesterol, high density lipoprotein (HDL), triglycerides, total protein, albumin, prothrombin time (PT) and thromboplastin partial time (PTT) of both sexes. Hematological analysis showed no differences in any of the parameters examined (WBC count, platelet and hemoglobin estimation) in either the control or treated group of both sexes. The urinalysis was negative for glucose, ketonic bodies, casts, red blood cells, and albumin in the control and treatment groups. There were no significant differences in the body and organ weights between controls and treated animals of both sexes. Pathologically, neither gross abnormalities nor histopathological changes were observed.
Medically important fungi found in hallux nails of university students from Cali, Colombia
(Mycopathologia, 2007-05-01) Álvarez, María Inés; Caicedo, Luz Dary
The presence of medically important fungi was studied in hallux nails scrapings obtained from 504 students (204 males, 300 females) of three universities in Cali. Specimens were examined by direct microscopic examination and fungal culture. Medically important fungi were found in 49 (9.7%) students, 24 (4.8%) had onychomycosis while the rest did not have nail lesions. Trichophyton rubrum was the most commonly isolated fungi in students with lesions, where as T. mentagrophytes predominated in healthy nails. Most of the students with fungi were males. The prevalence of fungi was higher in individuals between 26 and 35 years. No association was observed between fungi and practicing sports or undergoing pedicures. These results suggest that dermatophytes can be found in healthy hallux nails, which can be reservoirs of pathogenic fungi.
Evaluation indicators in the nursing teaching
(Colombia Medica, 2007-10) Triviño, Zaider; Stiepovich, Jasna
The objective of this work is to carry out a critical and reflexive analysis about the evaluation indicators in the nursing learning-teaching, starting from the supposition that is considered, greater persistence of the pedagogical traditional model, repetitive methods of learning and a gap theoretical-practical, from the curriculum design to the process of evaluation. The problems perceived and observed are presented and some alternatives are proposed with indicators for them. First, the conceptual aspects of evaluation are, indicator and standard. Second, the purpose, pedagogical context and evaluation as well as the evaluation process in nursing and substantive functions are shown, with a proposal of indicators for the same, from the nursing program. What underlies through the article is the use of some indicators, to guide the productivity of the program and to indicate weak and strong points. © 2007 Corporación Editora Médica del Valle.
Mechanical and chemical behavior of sintered 6061 powder Aluminium Alloy reinforced with CuAl2 particles
(Physica Status Solidi (C) Current Topics in Solid State Physics, 2007-10-25) Vanegas, O.; Castro, I. J.; Barona, W.; Sánchez Sthepa, H.
A 75 μm 6061 powder Aluminum Alloy (A.A) plus 5, 10 and 15 wt% CuAl2 particles were prepared by mixing the powders in a small milling tumbler during 4 hours at 58 rpm. The samples were compacted at room temperature and at (210±5) °C by using a 38 mm diameter uniaxial floating die. A vacuumed chamber set with an Argon flux was adapted to sinter the samples at 555 °C, temperature that was determined by the exothermic peak of CuAl2 and sinter time was experimentally determined in 13/4 h. The sintered samples were tailored to perform the tension and hardness tests. The 10wt% reinforced Alloy exhibits the best properties: the fluency stress is higher in approximately 130% as compared with the plain alloy. Also the maximum stress, the stress at 0.1% strain and the Young modules are better. The Tafel polarization curves show that corrosion resistance increases as the reinforcement particles increase. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and characterization of Fe0.79Si0.09C 0.12 by mechanical alloying
(Physica Status Solidi (C) Current Topics in Solid State Physics, 2007-10-25) Mercado, W. Barona; Ochoa, J. Cuevas; Fajardo, Marta; Pérez Alcázar, Germán Antonio; Sthepa, H. Sánchez
Iron silicon carbide Fe0.79Si0.09C0.12 was prepared by mechanical alloying from elemental powders, with a ball‐to‐powder weight ratio of 20:1. This synthesis was carried out in two stages: in the first stage cementite Fe3C was prepared from elemental iron and carbon powders, the mixed powders were milled for 30 hours. In the second stage Fe0.79Si0.09C0.12 was prepared from cementite Fe3C and Silicon elemental powder as precursors, the samples were milled for 1, 3, 5, 10, 15, 20, 25, 30 and 35 hours. The alloy progress for each milling time was evaluated by X‐ray diffraction (XRD) and 57Fe Mössbauer spectrometry. Nanocrystalline Fe3C powders were obtained from Fe and C, with an average grain size of 15 nm. It was possible to prepare metastable iron silicon carbide such as Fe0.79Si0.09C0.12 and Fe0.81Si0.02C0.17 and their respective hyperfine parameters are reported. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A note on the use of dolphins as bait in the artisanal fisheries off Bahía Solano, Chocó, Colombia
(Journal of Cetacean Research and Management, 2008) Avila, Isabel C.; García, Carolina; Bastidas, Juan Carlos
We evaluated dolphin hunting for bait in Bahía Solano, Chocó, Colombia, from July 2005 to April 2006. We interviewed 122 fishermen (18.2% of the registered fishermen in the zone) and obtained data from landings at a fishing company. Only fishermen using longlines (n=94; 37.3%) confirmed using dolphins for bait. One adult dolphin was reported to provide enough bait for two fishing bouts, capturing between 75 kg and 152 kg of fish. We could not obtain additional information about date, specific location or dolphin species, but the most probable captured species are Tursiops truncatus (common bottlenose dolphin) and Stenella attenuata (pantropical spotted dolphin), since these are the most commonly encountered species in coastal waters. A minimum of nine dolphins were reported killed during the study period (1 dolphin/month). Extrapolating these numbers to all fishermen using longlines in the region (250), an absolute minimum of 24 dolphins might have been taken during the study period (2.7 dolphins/month). Presumably many fishermen even while they also took dolphins, did not communicate this to the interviewers, considering dolphins are legally protected in Colombia. Fish species captured with dolphin bait include Brotula clarkae, Cephalopholis acanthistius, Epinephelus cifuentesi, Mustelus lunulatus and Lobotes pacificus.
Vacunal cover in children 12 to 47 months old of social and economic 1 and 2 layers in the urban zone of Cali, year 2002
(Colombia Medica, 2008) Rojas, Jorge H.; Zapata, Helmer; Alzate, Alberto; Rodríguez, Álvaro
Objective: To estimate prevalence of complete vaccination sketch in children of ages of 12 to 47 months old in strata 1 and 2 into urbane zone of Cali in the year of 2002 according to biologics and the categories of socio-demographic variables of the family, the mother and child. Methods: The research corresponded to a cross section survey. The sample size used in the estimation process was 4452 children, drawn from conglomerates combined with strata by means of probabilistic sampling. The information was analyzed with Epi-Info version 6.04, with the Csample module for complex samples analysis. Results: The vaccination coverage with complete sketch for the first year was 65.8 (62.1-69.5), with significative differences for one and two strata (x2=42.4, p< 0.05). In the group of 12 to 47 months the belower coverages according to biologic were for anti-Haemphilus influenzae type B and anti-hepatitis B 71.8% (68.6-75) and 92.2% (90.1-94.3) respectively. Statistical association was found (test x2, p< 0.05) in comparing vaccination coverages with mother’s age, mother’s schooling, mother’s working time, family income and type of health system affiliation. Conclusions: The vaccination coverages in the studied population for some biologics were below, bearing in mind that the rule established by Colombian Ministry of Social Protection is to keep coverages into a minimum of 95%.
Synthesis and characterization of Fe6W6C by mechanical alloying
(Hyperfine Interactions, 2008-05-23) Barona Mercado, W.; Cuevas, J.; Castro, I. Y.; Fajardo, Marta; Pérez Alcázar, Germán Antonio; Sánchez Sthepa, Héctor
The properties of the double iron and tungsten carbide prepared by mechanical alloying technique (MA) from elemental powders are reported. The samples were milled for 1, 3, 5, 10, 15, 20, 25 and 30 h. The alloy progress for each milling time was evaluated by X-ray diffraction (XRD) and 57Fe Mössbauer spectrometry. Once the alloy was consolidated two sorts of paramagnetic sites and a magnetic distribution were detected according to the Mössbauer fitting. The majority doublet could correspond to Fe6W6C ternary carbide as X-ray diffraction suggests, and the other could be Fe3W3C. The hyper fine parameters are reported. Vickers microhardness measurements of 30 h milled sample was conducted at room temperature with a load of 0.245 N for 20 s.

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