1,042 research outputs found

    Web-Based Laboratory Using Multitier Architecture

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    Modelo dinámico del comportamiento de la producción mercantil en Camagüey, Cuba

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    Se determinó un modelo dinámico entre los indicadores internos conducentes del crecimiento para obtener un vector autorregresivo (VAR). Se aplicaron métodos cuantitativos (estadísticos y econométricos) para expresar una concepción dinámica del comportamiento de la producción mercantil sobre la base de ciertos indicadores conducentes. El proceso de obtención del modelo ofreció las variables causales de la producción mercantil: gasto de materiales, salarios y rendimiento agrícola de cultivos temporales. Por otra parte, las elasticidades parciales (0,419; 0,390 y 0,258, respectivamente) ofrecen la variación porcentual en la producción mercantil para una variación porcentual en dichas variables, con un nivel de significación del 5 %. El VAR, a través de la función de impulso-respuesta, expresa cómo varía porcentualmente la PM desde el periodo comprendido entre 2007 y 2009 para una desviación de 0,124 % del gasto material

    Response of obesity-resistant BALB/c mice to a ketogenic diet

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    Introduction. The ketogenic diet (KD) is a high-fat, low-carbohydrate diet in which the body undergoes metabolic adjustments that stimulate ketogenesis, thereby increasing circulating ketone bodies. Loss of body weight is attributed to these adjustments, as well as neuroprotective properties. However, the mechanisms involved are still not fully elucidated. That aim of this work was to evaluate the effect of a ketogenic diet on body composition, feeding behavior and glucose metabolism in mice of the BALB/c strain, a mouse model resistant to obesity. Materials and methods. BALB/c mice of both sexes, 12 weeks old, were divided into KD and control groups, which received a ketogenic diet (Research Diets) or standard chow (LabDiet 5001), respectively, for 23 days. Throughout the experiment, body weight gain, water and food intake were measured, whereas body mass index (BMI), the percentage of interscapular, inguinal, and visceral adipose tissue and blood b-hidroxybutyrate levels were measured at the end of the protocol. In addition, glucose tolerance tests were carried out at the beginning and at the end of the experiment. Results. Similar body weight gain (10%) was observed in males and females on KD compared to the control group (p\u3c0.05). However, a higher BMI was observed only in males. The KD group consumed 50% less food in both sexes, whereas water consumption was diminished 25% in males and 50% in females, compared to the control (p= 0.0001). The estimated energy intake was lower (12 Kcal) in males on ketogenic diet, but not in females. Regarding the metabolic state at day 23, in KD mice levels of b-hidroxybutyrate increased to 0.4 mmol/L in males and 0.7 mmol/L in females. Mice of both sexes on KD showed increased inguinal and visceral fat, when compared to the control group on standard chow. At day 23, the glucose tolerance test showed an increase in the area under the curve, indicating impaired glucose tolerance, in both males and females on KD. Conclusions. In obesity-resistant BALB/c mice, the consumption of a ketogenic diet for a short period induces a state of nutritional ketosis accompanied by weight gain, increased fat tissue, and impaired glucose intolerance

    Nonconventional Wastewater Treatment for the Degradation of Fuel Oxygenated (MTBE, ETBE, and TAME)

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    Catalytic wet air oxidation (CWAO) is a nonconventional wastewater treatment, consisting of oxygen pressure releasing inside a reactor in order to degrade organic compounds dissolved in water, using a solid catalyst in the presence of an activated O2 species, usually at temperatures ranges of 125–250°C and pressures of 10–50 bar. CWAO can reduce operating costs of conventional treatment due to the use of ideal catalyst that is able to improve reaction conditions at temperatures and pressures as mild as possible, simultaneously setting high catalytic activity and long-term stability of heterogeneous catalysts. Oxygenated fuels are gasoline additives in reformulated gasoline and oxyfuels. In the beginning, they provided an alternative solution of environmental problems, such as greenhouse gas emissions and octane enhancement, caused by fossil fuel use. The oxygenated fuels frequently used are methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). However, there is environmental impact from oxygenated fuel hydrocarbons related to widespread contamination of groundwater and other natural waters. Our research group developed a wide study in order to evaluate several catalysts (Ru, Au, Cu, and Ag supported on Al2O3, Al2O3-CeO2, and TiO2-CeO2) and to obtain the best for the efficiency of the oxidation process

    Desarrollo de emulsiones con aceite esencial de naranja formuladas con diferentes biopolímeros.

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    Recientemente se ha presentado un gran interés en la industria alimenticia y en la medicina preventiva por la búsqueda de antioxidantes naturales, principalmente obtenidos de extractos vegetales; actualmente se considera un antioxidante natural el aceite esencial de naranja, sin embargo, a la vez es muy inestable a ciertos factores ambientales como luz, oxígeno, humedad, pH, etc.; una manera de proteger la degradación es por medio de una emulsión. El propósito de este estudio fue desarrollar emulsiones de aceite esencial de naranja utilizando β-ciclodextrina, concentrado de proteína de suero y goma xantana. Las combinaciones de los biopolímeros fue de 0, 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.8, 0.85, 0.9, 1 %, realizándose 10 fórmulas de emulsiones (identificadas como 1 a 10). El análisis de tamaño de partícula nos proporcionó un diámetro promedio superficial [D3,2] y diámetro promedio volumetrico [D 4,3] de 1.6 y 2 μm respectivamente. Se obtuvó la tasa de coalesencia de las emulsiones de 1.35x10-8 a 9.13 x10-9, en las emulsiones 1, 2, 6, 7, 8 y 9. Siendo estables solo 6 fórmulas y presentarse 4 inestables, de las cuales presentaron índices de cremado entre 15-40 %. Este estudio mostró que βCD, WPC, y XG son factibles para el uso como materiales de pared en las formulaciones de emulsiones para el aceite esencial de naranja

    Spermatozoa Obtained From Alpaca vas deferens. Effects of Seminal Plasma Added at Post-thawing

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    The viscous seminal plasma (SP) is currently a major impediment to the handling of ejaculate and the development of some biotechnologies in South American camelids. The vas deferens-collected spermatozoa of alpacas is a useful technique to avoid this problem. On the other hand, SP contains a large protein component that has been implicated in the function of spermatozoa within the female reproductive tract. In this sense, the low fertility achieved using transcervical insemination with frozen-thawed spermatozoa in alpacas could be improved by adding SP. This study aimed to evaluate the effect of the whole SP on some in vitro parameters of alpaca spermatozoa after the freezing-thawing-process and the fertility after artificial insemination. It would contribute to a better understanding of the interaction between thawed sperm cells and SP. Spermatozoa were obtained by surgically diverted vas deferens. The samples were diluted with a Tris-based extender, packaged in straws, and frozen. At thawing, each straw was divided into two post-thawing conditions: with the addition of 10% of PBS (control) or with 10% SP (treatment). The sperm cells were evaluated using dynamic parameters, sperm cell morphology, and morphometry. Fertility was assessed by an artificial insemination trial. All in vitro parameters were analyzed by ANOVA. A heterogeneity test was scheduled for the fertility trial. After the freezing-thawing process, motility and plasma membrane functionality was improved when SP was added. No differences were found for post-thaw viability between the control and treatment samples. The percentage of normal cells was higher with SP at post-thawing, and a decrease of the presence of bent tailed spermatozoa with a droplet in the SP group was observed. The length of the head spermatozoa was 3.4% higher in the samples with PBS compared to those in which SP was added. Females pregnant at day 25 post-insemination were 0/12 (with SP inside the straw) and 1/10 (without SP inside the straw). In conclusion, the presence of 10% SP at post-thawing improves sperm cells' motility, functionality, and morphology, indicating that it would be beneficial to improve the frozen-thawed alpaca's physiology spermatozoa. More fertility trials must be developed to increase this knowledge

    Application of Silver Nanoparticles for Water Treatment

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    In recent past development of silver nanoparticles and their application in the treatment of wastewaters is becoming a major area of research. It is mainly applicable to the removal of three major pollutants like pesticides, heavy metals, and microorganisms. Variety of synthesis techniques have been reported for preparation and characterization of silver nanoparticles. In our research, we synthesized Ag nanoparticles supported on ZrO2 and ZrO2-CeO2 by a “deposit-precipitation method” as the first step and later sequentially synthesized Ag-Au supported on ZrO2 and ZrO2-CeO2 by Redox method. Catalysts were evaluated in catalytic wet air oxidation (CWAO) of methyl tert-butyl ether and phenol. The CWAO is a liquid phase process for the treatment of organic pollutants operating at temperatures in the range of 100–325°C at 5–200 bar pressures. The selectivity and efficient of catalysts were evaluated by total organic carbon (TOC) and high-performance liquid chromatograph (HPLC). Ideally, the total mineralization of pollutants into CO2 and H2O is preferred

    B cell–adaptive immune profile in emphysema-predominant chronic obstructive pulmonary disease

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    Cigarette smoke, the major risk factor for COPD in developed countries, causes pulmonary inflammation that persists long after smoking cessation, suggesting self-perpetuating adaptive immune responses similar to those that occur in autoimmune diseases. Increases in the number and size of B cell–rich lymphoid follicles (LFs) have been shown in patients in severe stages of COPD (4), and increased B-cell products (autoantibodies) have been observed in the blood and lungs of patients with COPD (5, 6). Oligoclonal rearrangement of the immunoglobulin genes has been observed in B cells isolated from COPD LFs, suggesting that a specific antigenic stimulation drives B-cell proliferation. Consistently, we have shown that in the COPD lung, there is an overexpression of BAFF (B-cell activation factor of the TNF family), which is a key regulator of B-cell homeostasis in several autoimmune diseases (7) and is involved in the growth of LFs in COPD. However, a network analysis of lung transcriptomics showed that a prominent B-cell molecular signature characterized emphysema preferentially but was absent in AD independently of the degree of airflow limitation (8). In the current study, we investigated the correlation between B-cell responses in lung tissue from patients with COPD and healthy smokers, and the extent of emphysema versus airflow limitation
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