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A plastic injection waste known as "purge" cannot be reintegrated into the recycling chain due to its shape, size, and composition. Grinding these cannot be carried out with traditional mills due to significant variations in size and shape. This work proposes a process and the design of a device that operates with solar energy to cut the purges without exceeding the degradation temperature. The size reduction allows reprocessing, revalorization, and handling. The purges are mixtures of processed polymers, so their characterization information is unavailable. Some characterizations were conducted before the design of the process and after the cut of the purges. Some of the most representative purges in a recycling company were evaluated. The flame test determines that all material mixtures retain thermoplasticity. The hardness (Shore D) presented changes in four of the purges being assessed, with results in a range of 59-71 before softening and 60-68 after softening. Young's modulus was analyzed by the impulse excitation technique (IET), which was 2.38-3.95 GPa before softening and 1.7-4.28 after softening. The feasibility of cutting purges at their softening temperature was evaluated. This was achieved in all the purges evaluated at 250-280 °C. FTIR allowed for corroboration of no significant change in the purges after softening. The five types of purges evaluated were polypropylene-ABS, polycarbonate-ABS-polypropylene, yellow nylon 66, acetal, and black nylon 66 with fillers, and all were easily cut at their softening temperature, allowing their manipulation in subsequent process steps.
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Herein, we report the synthesis, structural and microstructural characterization, and thermoelectric properties of AgSnm[Sb0.8Bi0.2]Te2+m and Br-doped telluride systems. These compounds were prepared by solid-state reaction at high temperature. Powder X-ray diffraction data reveal that these samples exhibit crystal structures related to the NaCl-type lattice. The microstructures and morphologies are investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDS), and high-resolution transmission electron microscopy (HRTEM). Positive values of the Seebeck coefficient (S) indicate that the transport properties are dominated by holes. The S of undoped AgSnm[Sb0.8Bi0.2]Te2+m ranges from +40 to 57 µV·K-1. Br-doped samples with m = 2 show S values of +74 µV·K-1 at RT, and the Seebeck coefficient increases almost linearly with increasing temperature. The total thermal conductivity (κtot) monotonically increases with increasing temperature (10-300 K). The κtot values of undoped AgSnm[Sb0.8Bi0.2]Te2+m are ~1.8 W m-1 K-1 (m = 4) and ~1.0 W m-1 K-1 (m = 2) at 300 K. The electrical conductivity (σ) decreases almost linearly with increasing temperature, indicating metal-like behavior. The ZT value increases as a function of temperature. A maximum ZT value of ~0.07 is achieved at room temperature for the Br-doped phase with m = 4.
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Traditional medicine in Latin America and mainly in Mexico represents an essential alternative for treating different diseases. The use of plants as medicine is the product of a rich cultural tradition of the indigenous peoples, in which a great variety of species are used for the treatment of gastrointestinal, respiratory, and mental diseases and some other sicknesses; the therapeutic efficacy that they possess is due to the properties that derive from the active ingredients of plants principally antioxidants, such as phenolic compounds, flavonoids, terpenes, and tannins. An antioxidant is a substance that, at low concentrations, delays or prevents substrate oxidation through the exchange of electrons. Different methods are used to determine the antioxidant activity and the most commonly used are described in the review. Cancer is a disease in which some cells multiply uncontrollably and spread to other parts of the body, a process known as metastasis. These cells can lead to the formation of tumors, which are lumps of tissue that can be cancerous (malignant) or noncancerous (benign). Generally, the treatment of this disease consists of surgery, radiotherapy, or chemotherapy, which have side effects that decrease the quality of life of patients, so new treatments, focusing on natural resources such as plants, can be developed. This review aims to gather scientific evidence on the antioxidant compounds present in plants used in traditional Mexican medicine, specifically as antitumor treatment in the most common cancer types worldwide (e.g., breast, liver, and colorectal cancer).
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Resumen El modelo biomédico para enfermedades crónicas no transmisibles considera que los enfermos deben responder automáticamente a una prescripción. Sin embargo, esto conduce al enfermo a confrontarse con su grupo social, debido a que una fuerza invisible y controladora lo configura y conduce a desarrollar una disposición contraria a la requerida en el plan de tratamiento, este elemento se conoce como cultura. El propósito del presente artículo es exhortar a la reflexión sobre la influencia de la cultura en el descontrol de este tipo de enfermedades. Se propone diferenciar entre enfermedad y padecimiento, denominando paciente a la persona cuando se atienda la enfermedad y padeciente cuando se atienda el padecimiento. Por tanto, atender al padeciente implica considerar preocupaciones, miedos, creencias, expectativas, emociones y sentimientos, así como las repercusiones de la enfermedad en la vida. Para demostrar esta afirmación se describe cómo conceptualizamos cultura, cuál es su función y por qué es imprescindible intervenir en el contexto sociocultural del padeciente.
Abstract The biomedical model for chronic non-communicable diseases considers that people with the disease must respond automatically to their medical prescription. However, this leads to a confrontation of sick people against their social group since an invisible and controlling force shapes and leads the patient into developing a disposition opposed to their required treatment plan, this element is better known as culture. The purpose of this study is to encourage reflection about the influence of culture in the lack of control regarding this type of diseases. It is proposed to differentiate between disease and illness, calling patient when treating the disease and sufferer when treating the illness. Hence, treating the sufferer includes considering worries, fears, beliefs, expectations, emotions, and feelings, as well as repercussions of the disease on their life. To proof this statement, the concept of culture is described and conceptualized, as well as its function, and why it is of vital importance to intervene in the socio-cultural context of the sufferer.
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PURPOSE: Periodontitis is associated with a dysbiosis of periodontopathic bacteria, which stimulate the interleukin (IL)-23/IL-17 axis that plays an essential role in the immunopathogenesis of this disease, leading to alveolar bone destruction through receptor activator of nuclear factor κB ligand (RANKL). IL-23 receptor mRNA (IL-23R) has been identified in periodontitis, and IL-17 receptor A mRNA (IL-17RA) and its protein have not yet been evaluated in patients with periodontitis. In this study was measure IL-23R and IL-17RA in gingival tissue (GT) from patients with generalized chronic periodontitis (GCP) and generalized aggressive periodontitis (GAP) and to explore correlations with clinical parameters. METHODS: We included 16 healthy subjects (HS), 18 patients with GCP, and 14 with GAP. GT samples were collected during periodontal surgery. Both IL-23R and IL-17RA were detected by enzyme-linked immunosorbent assay. RESULTS: The results were analyzed with Mann-Whitney U test and Spearman' rank correlation coefficients using SPSS version 25.0. We found lower IL-23R levels in patients with GCP and GAP than in HS. Contrarily, we observed higher IL-17RA levels in GCP and GAP patients than in HS. Moreover, we found negative correlations between IL-23R in GT and probing depth and clinical attachment loss (CAL). Likewise, a positive correlation of IL-17RA in GT with CAL was found. CONCLUSIONS: The results of these findings suggest that the reverse behavior between IL-23R and IL-17RA in periodontitis patients may also be involved with the activation of RANKL, which promotes alveolar bone loss.
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The aim of this study was the characterization of a collection of 8 methicillin-resistant Staphylococcus aureus (MRSA) isolates, obtained from samples of fresh cheese (Doble Crema) produced from raw cow milk in small dairies in Colombia. All the isolates harbored the mecA and Panton-Valentine leukocidin (PVL) genes, presented with SCCmec type IV, and belonged to multilocus sequence type 8 and spa type 024. Seven isolates presented 3 closely related pulsed-field gel electrophoresis profiles. Three of them carried the staphylococcal enterotoxin B gene. The isolates were resistant to cefoxitin, oxacillin, penicillin, and ampicillin and susceptible to all non-ß-lactams antibiotics tested, with minimum inhibitory concentration values for oxacillin of 4 to 8mg/L. The isolates belonged to the community-acquired MRSA group, suggesting a human source of contamination. The risk of human infection by MRSA via contaminated foods is considered low, but contaminated food commodities can contribute to the worldwide dissemination of clones of community-acquired MRSA.
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Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Meticilina , Animais , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Bovinos , Queijo , Colômbia , Feminino , Humanos , Testes de Sensibilidade Microbiana , Leite/efeitos dos fármacos , Infecções Estafilocócicas , Staphylococcus aureus/isolamento & purificaçãoRESUMO
Human natural killer (NK)-like CD8+ T-cells are singular T-cells that express both T and NK cell markers such as CD56; their frequencies depend on their differentiation and activation during their lifetime. There is evidence of the presence of these innate CD8+ T-cells in the human umbilical cord, highlighting the necessity of investigating whether the NK-like CD8+ T-cells arise in the early stages of life (gestation). Based on the presence of cell surface markers, these cells have also been referred to as CD8+KIR+ T-cells, innate CD8+ T-cells, CD8+CD28-KIR+ T-cells or NKT-like CD8+CD56+ cells. However, the functional and co-signaling significance of these NK cell receptors on NK-like CD8+ T-cells is less clear. Also, the diverse array of costimulatory and co-inhibitory receptors are spatially and temporally regulated and may have distinct overlapping functions on NK-like CD8+ T-cell priming, activation, differentiation, and memory responses associated with different cell phenotypes. Currently, there is no consensus regarding the functional properties and phenotypic characterization of human NK-like CD8+ T-cells. Environmental factors, such as aging, autoimmunity, inflammation, viral antigen re-exposure, or the presence of persistent tumor antigens have been shown to allow differentiation ("adaptation") of the NK-like CD8+ T-cells; the elucidation of this differentiation process and a greater understanding of the characteristics of these cells could be important for their eventual in potential therapeutic applications aimed at improving protective immunity. This review will attempt to elucidate an understanding of the characteristics of these cells with the goal toward their eventual use in potential therapeutic applications aimed at improving protective immunity.
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Cell-cell interactions play essential roles in the regulation of gametogenesis. The involvement of junctional complexes in permeability barriers, for example, provides structural and physiological support for male germ-cell development. This study describes morphological characteristics of the reproductive system of Gymnotus carapo, a neo-tropical freshwater fish widely distributed in South and Central America, focusing on the detection of permeability barriers using morphological and biochemical approaches. Ultrastructural analysis of testes treated with the lanthanum nitrate exclusion technique showed that the tracer penetrated the interstitial compartment of the testis, surrounding and appearing within cysts containing spermatogonia and spermatocytes in early stages of meiosis, but was not detected in the spermatid cysts or inside the lumen of spermatogenic tubules. These results suggest the presence of a permeability barrier that is stabilized after meiosis is completed and serves to protect the haploid cells from the vascular system. In the spermatic-duct region, the tracer was obstructed near the lumen of the duct. Junctional complexes and focal tight junctions between adjacent cells were observed in the testis and spermatic duct. Freeze-fracture methods indeed confirmed the presence of tight junctions, which were visualized as parallel rows of individual particles between adjacent cells. More evidence supporting the existence of a permeability barrier was gathered from differences observed in the electrophoretic protein profiles of testis and spermatic-duct fluids compared to blood plasma. Together, these observations demonstrate the existence of a permeability barrier formed by tight junctions in the testis and spermatic duct of G. carapo.
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Gimnotiformes/fisiologia , Espermatogênese/fisiologia , Testículo/citologia , Junções Íntimas/fisiologia , Ducto Deferente/citologia , Animais , Permeabilidade da Membrana Celular/fisiologia , MasculinoRESUMO
Many of the inflammatory diseases are becoming common in ageing society throughout the world. The clinically used anti-inflammatory drugs suffer from the disadvantage of side effects. Alternative to these drugs are natural products, since ancient times traditional medicines are being used for the treatment of inflammation. In the present study, four flavanones isolated from Eysenhardtia platycarpa leaves with a potent pharmacological activity were formulated in effective drug delivery systems: nanoemulsion and polymeric nanoparticles for topical use as novel anti-inflammatory topical formulations. Nanoemulsion system exhibited droplet sizes less than 70 nm and polymeric nanoparticles with a size of 156-202 nm possessed zeta potential values less than -25 mV that provided good stability and obtained high entrapment efficiency (78-90%). In vitro release and ex vivo permeation studies were performed on Franz-type diffusion cells and quantified by high performance liquid chromatography (HPLC), all formulations showed steady state release profiles over time and steady increase of flavanones in the skin permeation test. The anti-inflammatory activity, tested by TPA (12-O-tetradecanoylphorbol-13-acetate), induced oedema in mice ear suggesting that prenylated flavanones improve significantly their anti-inflammatory activity when are vehiculized in nanosized systems. Our results suggested that 5-hydroxy-7-methoxy-6-prenyl flavanone loaded nanoemulsion and polymeric nanoparticle could be proposed as potential topical anti-inflammatory formulations with the best properties for the treatment of inflammatory disorders.
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Anti-Inflamatórios não Esteroides/farmacologia , Otopatias/tratamento farmacológico , Edema/tratamento farmacológico , Fabaceae/química , Flavanonas/farmacologia , Pele/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Otopatias/induzido quimicamente , Edema/induzido quimicamente , Flavanonas/química , Flavanonas/isolamento & purificação , Humanos , Masculino , Camundongos , Estrutura Molecular , Nanoestruturas/química , Permeabilidade/efeitos dos fármacos , Folhas de Planta/química , Pele/metabolismo , Acetato de Tetradecanoilforbol/análogos & derivadosRESUMO
INTRODUCTION: The feeding behavior establishes a relation of humans with food, includes food habits that could be involved with oxidative stress. OBJECTIVE: To evaluate the relation of indicators of oxidative stress (lipid peroxides) and antioxidant (ascorbic acid, catalase, superoxide dismutase) with feeding behavior in adults of Teocuhitatlan Corona, Jalisco, Mexico. METHOD: Study observational, descriptive, cross-sectional of 44 adults with 43 to 88 years, was used a instrument of feeding behavior. The questionnaire were related to indicators of oxidative stress. Were used descriptive statistics, frequency distribution and analysis of covariance with adjustment variables, was considered significant p <0.05. RESULTS: The values of serum lipid peroxides were related to behaviors: consider the nutritional content as most important when choosing food (p = 0.042), dislike milk (p = 0.027), intake of sweets between meals (p = 0.001), habitual inclusion of vegetables and salads in main meal (p = 0.018). We do not found association in to values of ascorbic acid, cholesterol in low density lipoproteins and enzymatic activities of catalase and superoxide dismutase with food behaviors. DISCUSSION: The feeding behaviors analyzed in this study may be involved with development of oxidative stress and could be have protective or harmful effect in development to complications of chronic non-communicable diseases and aging in this population. This suggests to analyze demographic and socio-cultural aspects of region and besides analyzing the consumption and metabolic markers related to food.
Introducción: El comportamiento alimentario establece la relación del ser humano con la alimentación, comprende hábitos alimentarios que podrían intervenir en el desarrollo del estrés oxidativo. Objetivos: Evaluar la relación de indicadores de estrés oxidativo (lipoperóxidos) y capacidad antioxidante (ácido ascórbico, catalasa, superóxido dismutasa) con el comportamiento alimentario en adultos que residen en Teocuitatlán de Corona, Jalisco, México. Método: Estudio observacional, descriptivo, transversal, comparativo de 44 adultos de 43 a 88 años de edad. Se aplicó un instrumento de comportamiento alimentario. Los resultados del cuestionario se relacionaron con los indicadores de estrés oxidativo. Se utilizó estadística descriptiva, distribución de frecuencias y análisis de co-varianza con ajuste de variables, se consideró una significancia de p.
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Antioxidantes/análise , Comportamento Alimentar , Estresse Oxidativo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Dieta , Inquéritos sobre Dietas , Feminino , Preferências Alimentares , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To assess the impact of a web-based intervention supplemented with text messages to reduce cancer risk linked with smoking, unhealthy diet, alcohol consumption, obesity, sedentary lifestyle and sun exposure. METHODS: A total of 2001 voluntary adolescents from Spain and Mexico were recruited between 2009 and 2012 and randomly assigned to: one control group and two experimental groups, which received exclusively the online intervention (experimental group 1) or the intervention supplemented with encouraging text messages (experimental group 2). The educational intervention was based on both: successful psychosocial models (i.e. A.S.E. and Transtheoretical model) and the school curriculum. RESULTS: After a 9-month follow-up, the prevalence of students who did not eat fruit was reduced significantly in all groups: experimental group 1 (-62.6%), experimental group 2 (-71.5%) and even the control group (-66.8%). Being overweight was only reduced in the experimental group 2 (-19.6%). The total cancer behavioral risk score, which ranged from 0 to 100 points (highest risk), was significantly reduced in the experimental group 1 (-3.5 points) and in the experimental group 2 (-5.3 points). The text-supplemented online intervention increased the probability of improving the post-test total cancer behavioral risk (OR=1.62). CONCLUSION: The web-based intervention supplemented with text messages had a positive global impact, but it lead to only minimal changes in risky behaviors. This intervention appears useful in controlling overweight adolescents. CLINICAL TRIAL REGISTRATION NUMBER: ISRCTN27988779.
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Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/prevenção & controle , Estudantes/psicologia , Envio de Mensagens de Texto/estatística & dados numéricos , Logro , Adolescente , Criança , Comportamento de Escolha , Detecção Precoce de Câncer , Feminino , Seguimentos , Indicadores Básicos de Saúde , Humanos , Internet , Masculino , México , Neoplasias/diagnóstico , Assunção de Riscos , Fatores Socioeconômicos , Espanha , Estudantes/estatística & dados numéricos , Inquéritos e QuestionáriosRESUMO
Este artigo é um convite à reflexão sobre os discursos que abordam as estratégias utilizadas na resolução de conflitos familiares por alguns adolescentes da cidade de Mérida, em Yucatán, México; a partir do Socioconstrutivismo, oferecemos também um olhar sobre o discurso institucional da violência. Da mesma forma pretende compartilhar uma série de questionamentos surgidos de nossas reflexões ao terminar um trabalho de pesquisa realizado por diferentes grupos, em três cidades do México. A pesquisa inicial foi baseada em entrevistas semiestruturadas.(AU)
This article invites to reflect upon the discourses about family conflict resolution, that some adolescents from the city of Merida in Yucatan, Mexico, utilize; it also offers a view, from a socioconstructionist stance, of the institutionalized discourse on violence. We would like to share the questions emerging from our reflections once we finished the initial research with Mexican youth and their families, conducted by different teams, in different cities in Mexico. Such research was published, in December of 2010, as part of a book en which the results of the three different locations were presented. The original research was based on semi-structured interviews.(AU)
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BACKGROUND: The overall number of cancer cases is increasing and, therefore, strengthening cancer prevention has become a priority. The institutions responsible for its control establish guidelines for primary prevention. These include recommendations, such as: not smoking, following a healthy diet, doing daily physical exercise or avoiding overweight. Adolescence is a period of adoption and/or consolidation of health behaviors, and both school- and family-based interventions have proven effective to improve them. Furthermore, online and mobile phone educational interventions are encouraging. Consequently, the main aim of this study is to assess the efficacy of an intervention in which these requirements (school, family, the Internet and SMS) are combined to prevent behavioral cancer risk. METHODS: This protocol describes the design and implementation of a complex online program that includes a randomized controlled trial put into practice in two countries: Spain and Mexico. Adolescents and adults of their environment (relatives and teachers) who voluntarily participate will be randomly assigned to the experimental group or to the control group once they have completed the online pre-test. The experimental group members will have free access to a tailor-made and interactive website (http://www.alertagrumete.com). During the academic year, this website will be periodically updated with different school and leisure activities related to the avoidance of risk behaviors. To encourage participation, the program includes a competition that gives rewards to the winners. SMS are also sent to students to stimulate the adoption of healthy behaviors and as a reminder of participation. Finished the intervention, an online post-test is performed in both groups and the impact on the risk behaviors is therefore assessed. DISCUSSION: The program is pioneer, since it combines many components which have already proven effective in previous researches. Moreover, it aims to compare efficacy in two countries with different socio-economic levels to find out if these approaches are equally effective in countries with a lower income level. However, the vertiginous evolution of the Internet and mobile phones may make this tool less attractive for adolescents, who may prefer social networks and other mobile phone applications which are nowadays massively used by their peers. TRIAL REGISTRATION: ISRCTN27988779.
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Promoção da Saúde/métodos , Neoplasias/prevenção & controle , Adolescente , Adulto , Telefone Celular , Criança , Comportamentos Relacionados com a Saúde , Humanos , Internet , México , Projetos de Pesquisa , EspanhaRESUMO
The growth kinetics, sporulation, and toxicity of Bacillus thuringiensis var. israelensis were evaluated through the analysis of batch cultures with different dissolved oxygen (DO) profiles. Firstly, DO was maintained constant at 5%, 20%, or 50% throughout fermentation in order to identify the most suitable one to improve the main process parameters. Higher biomass concentration, cell productivity, and cell yield based on glucose were obtained with 50% DO. The higher aeration level also resulted in higher spore counts and markedly improved the toxic activity of the fermentation broth, which was 9-fold greater than that obtained with 5% DO (LC(50) of 39 and 329 mg/L, respectively). Subsequently, using a two-stage oxygen supply strategy, DO was kept at 50% during the vegetative and transition phases until the maximum cell concentration was achieved. Then, DO was changed to 0%, 5%, 20%, or 100% throughout sporulation and cell lysis phases. The interruption of oxygen supply strongly reduced the spore production and thoroughly repressed the toxin synthesis. On the contrary, when DO was raised to 100% of saturation, toxic activity increased approximately four times (LC(50) of 8.2 mg/L) in comparison with the mean values reached with lower DO levels, even though spore counts were lower than that from the 50% DO assay. When pure oxygen was used instead of normal air, it was possible to obtain 70% of the total biomass concentration achieved in the air assays; however, cultures did not sporulate and the toxin synthesis was consequently suppressed.
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Bacillus thuringiensis/crescimento & desenvolvimento , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/biossíntese , Endotoxinas/biossíntese , Proteínas Hemolisinas/biossíntese , Oxigênio/metabolismo , Esporos Bacterianos/crescimento & desenvolvimento , Toxinas de Bacillus thuringiensis , Biomassa , Meios de Cultura/química , FermentaçãoRESUMO
BACKGROUND: The obesity and abnormal blood glucose level has been associated with cervical cancer development; however, few studies have been performed about this relation. OBJECTIVE: Evaluate the blood glucose levels and body mass index (BMI) in women with human papilloma virus infection (HPV-I) and cervical intraepithelial neoplasia (CIN-I). PATIENTS AND METHOD: Transversal study of 44 women diagnosed with HPV-I and CIN-I from September to December 2010 in Dysplasia Clinic of Regional Hospital of Guzman City, Federal entity of Jalisco, Mexico. The diagnoses were carried by biopsy of cervix, glucose test results were evaluated by spectrophotometry and determinate the BMI. RESULTS: The 18% (n=8) of women were without injury, 41% (n=18), with HPV-I and 41% (n=18) CIN-I. High blood glucose was observed in GIN-I versus without injury in the cervix (p = 0.05), the correlation was OR = 2.6 (95% CI: 1.090-6.52). The young women (19-35 years) were 17% high glucose, 28% normal glucose and 55% low glucose. In group of the medium age (35-65 years) 23% showed high glucose, 50% normal and 27% low. The BMI was not relation with diagnosis, although in the age (young versus age median p=0.001). CONCLUSION: These results support the proposal about the high levels of glucose in plasma and obesity could be risk cofactors in the development of preneoplasic lesion of cervix.
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Glicemia/análise , Índice de Massa Corporal , Infecções por Papillomavirus/sangue , Displasia do Colo do Útero/sangue , Neoplasias do Colo do Útero/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas , Neoplasias do Colo do Útero/patologia , Adulto Jovem , Displasia do Colo do Útero/patologiaRESUMO
In order to study in situ the growing process of porous materials, a new electrochemical differential photoacoustic cell (DPC) was developed. This system allows to obtain the thermal signals coming from the growing process of the pores without the external noise component. The DPC is a good system to growth porous silicon and study their growing process with reproducibility. The porous silicon samples were obtained by using electrochemical etching of (100) n-type silicon wafers with different nominal resistivity values in the range of 1-25 Omega cm. The samples were formed in a solution of hydrofluoric acid and ethanol having a composition ratio of 1:1 in volume with etching voltage of 10 V and an etching time of 2 min using back illumination provided by a laser beam with a wavelength of 808 nm. The porous samples were characterized by means of Raman microscopy, x-ray diffraction, and scanning electron microscopy. The crystallite sizes of the samples were obtained through the analysis of the micro-Raman spectra using a phonon confinement model, and the analysis of the x-ray diffractograms.
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Las actitudes de las malas relaciones humanas en el campo laboral se deben al olvido o al poco interés que se da al comportamiento que se debe mantener en este contexto, sin embargo hay muchos mecanismos para lograr un ambiente armonioso en las empresas
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Bolívia , ComportamentoRESUMO
La espectroscopia mediante celda fotoacústica diferencial (CFD) tiene la capacidad de medir in situ el desarrollo de diversos procesos dinámicos, entre otros la difusión de agua a través de una membrana. Mediante esta técnicase realizó el estudio de permeación de agua en huesos de rata Wistar sanos y descalcificados. Los huesos descalcificados fueron tratados mediante estimulación electromagnética a fin de evaluar la actividad celular en el hueso y, en su caso, detener la descalcificación del mismo. En este trabajo fue posible determinar la viabilidad de la CFD para la evaluación de densidad ósea indirectamente, siendo posible efectuar la evaluación in situ de permeación de agua, así como la cantidad de agua retenida en la estructura ósea al finalizar las pruebas en CFD.
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Fenômenos Eletromagnéticos , Osso e Ossos/efeitos da radiação , OsteoporoseRESUMO
Aborda la satisfacción de las usuarias externas del Programa de Atención Integral a la Mujer que demandan atención médica.
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Assistência Integral à Saúde , Qualidade da Assistência à Saúde , Mulheres , Serviços de Saúde da Mulher , Centros de Saúde , Serviços de SaúdeRESUMO
The expression of alpha-1,4-glucosidase activity was fluorometrically and electrophoretically assessed in the epididymal fluid and seminal plasma of stallions. alpha-Glucosidase specific activity in the epididymis increased significantly from the proximal caput to the cauda. Stallion epididymal glucosidase maintained activity in a wide range of pH, with two distinct peaks (around pH 4.0 and 6.0, respectively). Enzyme activities at different pH, inhibition assays with sodium dodecyl sulfate (SDS) and maltotriose (MTT, selective inhibitors of alpha-glucosidases "acidic" and "neutral" isoforms, described in other tissues) and the electrophoretic analysis in native and native/SDS-PAGE conditions, indicated that stallion epididymal glucosidase was due to two catalytically active forms. These forms, analyzed by non-denaturing electrophoresis, exhibited different electrophoretic mobility and molecular weight. Samples from the proximal caput of the epididymis were rich in Form II or "neutral" form, whereas the "acid" or Form I seemed to be predominate in the cauda epididymal region. At physiological pH, Form II was predominant in the seminal plasma. The physiological role(s) of these forms is uncertain, but based on their ability to hydrolyze glucosidic linkage, they probably are involved in degradation/modifications of epididymal fluid and/or spermatozoa glycoconjugates, thereby participating in plasma membrane remodeling associated with sperm maturation.