1,106 research outputs found

    Acute effects of unilateral sectioning the superior ovarian nerve of rats with unilateral ovariectomy on ovarian hormones (progesterone, testosterone and estradiol) levels vary during the estrous cycle

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    The present study analyzed the participation of the left and right superior ovarian nerves (SON) in regulating progesterone, testosterone, and estradiol serum levels in unilaterally ovariectomized rats on each day of the estrous cycle. For this purpose, ovarian hormone concentrations in serum were measured in animals with either sham-surgery, unilateral ovariectomy (ULO), unilateral sectioning of the SON, or sectioning of the SON innervation of the in situ ovary in rats with ULO

    Charged Higgs in 3-3-1 Model Through e−e+e^-e^+ Collisions

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    In this work we present an analysis of production and signature of charged Higgs bosons H2±H_2^{\pm} in the version of the 3-3-1 model containing heavy leptons at the CLIC (Cern Linear Collider). The production rate is found to be significant for the direct production of e−e+→H2+H2−e^{-} e^{+} \rightarrow H_{2}^{+} H_{2}^{-}. We also studied the possibility to identify it using their respective branching ratios.Comment: 16 pages, 9 Figures. arXiv admin note: substantial text overlap with arXiv:1408.5944; text overlap with arXiv:1311.0845, arXiv:1205.404

    Del contexto cultural al funcionamiento familiar. Conocimientos compartidos y relaciones familiares en adolescentes con intento de suicidio

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    El objetivo de este texto es identificar y comparar la estructura semántica del dominio cultural, el conocimiento promedio y el grado de consenso cultural sobre las causas del intento de suicidio, los síntomas previos y las estrategias de prevención del intento de suicidio, además evaluar el funcionamiento familiar entre adolescentes mexicanos con y sin intento de suicidio. Se presenta un estudio mixto metodológicamente que usa la técnica de listas libres y el inventario de recursos familiares en una muestra propositiva de 65 adolescentes (13 a 18 años) divididos en dos grupos: el grupo de adolescentes con tentativa suicida y un grupo control con adolescentes estudiantes sin antecedentes de conductas suicidas. Los problemas familiares fueron la principal causa del intento suicida, mientras que la depresión y la tristeza fueron síntomas previos a una tentativa suicida en ambos grupos. La ayuda psicológica y el desarrollo de habilidades de escucha en los padres fueron señaladas como las estrategias para la prevención del suicidio. Respecto del funcionamiento familiar, los adolescentes con tentativa suicida percibieron más conflictos familiares y menor comunicación y apoyo en sus familias en comparación con el grupo control. Los resultados sugieren un conocimiento compartido culturalmente sobre las causas, los síntomas y las estrategias de prevención del intento de suicidio en los adolescentes, el cual se confirma en la percepción del funcionamiento familiar. La familia, elemento central en la cultura mexicana, debe ser considerada en las estrategias de prevención del intento de suicidio en los adolescentes en México. AIM: The aim of the study was to identify and to compare the semantic structure of the cultural domain, the average knowledge and the degree of cultural consensus regarding knowledge of suicide attempts cause, symptoms and prevention strategies to suicide attempt and the family functioning among Mexican adolescents with and without previous suicide attempt. Method: It was a mixed study, using the free-listing technique and an inventory of family resources, with a non-random sample of 65 adolescents (13-18 years) divided in two groups. The suicide attempters group and the control group were high school students, without a history of suicide behaviors. Results: Family problems were identified as the most important cause of suicide attempts in both groups, while depression and sadness were identified as symptoms prior to the suicide attempt in both groups. Psychological aid and development of listening skills in the parents were the most frequent responses regarding prevention strategies to suicide attempt. Regarding family functioning teenage suicide attempters showed more family conflict, less family communication and support than teenage non suicide attempters. Conclusions: The results suggest a same cultural knowledge background regarding causes, symptoms prior and prevention strategies to suicide attempt in Mexican adolescents. Mexican culture centered in family relationships is important to be considered in design of prevention strategies to suicide attempt in adolescence in Mexico.ITESO, A.C

    Applications of Carboxylic Acids in Organic Synthesis, Nanotechnology and Polymers

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    Carboxylic acids are versatile organic compounds. In this chapter is presented a current overview of the use of carboxylic acids in a different area as organic synthesis, nanotechnology, and polymers. The application carboxylic acids in these areas are: obtaining of small molecules, macromolecules, synthetic or natural polymers, modification surface of nanoparticles metallic, modification surface of nanostructure such as carbon nanotubes and graphene, nanomaterials, medical field, pharmacy, etc. Carboxylic acids can be natural and synthetic, can be extracted or synthesized, presented chemical structure highly polar, active in organic reactions, as substitution, elimination, oxidation, coupling, etc. In nanotechnology, the use of acid carboxylic as surface modifiers to promote the dispersion and incorporation of metallic nanoparticles or carbon nanostructure, in the area of polymer carboxylic acids present applications such monomers, additives, catalysts, etc. The purpose of this chapter is to emphasize the importance of carboxylic acids in different areas, highlighting the area of organic synthesis, nanotechnology and polymers and its applications

    Effect of alkaline pre-treatment on the anaerobic biodegradability of coffee husk

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    The present paper deals with the mono-digestion of coffee husk during the operation of batch reactors and semi-continuous stirred tank reactor (S-CSTR) using both pre-treated residual at 3% Ca(OH)2 and without pre-treatment. The semi-continuous operation was carried out in 4 stages at different organic loading rate (OLR, [gVS L -1 d -1]) and hydraulic retention time (HRT, [d]) (OLR:HRT) ratios (0.1:90, 0.2:90, 0.2:45 and 0.2:30). As a result of the pre-treatment, up to 223% of the organic matter solubilisation was obtained. However, pre-treatment did not provide better results in biodegradability, observing a negative trend in methane yield when operating in S-CSTR, due to the accumulation of compounds from the fractionation of the lignin as is the case of polyphenols. The operation was further developed using the residual without pre-treatment. The highest methane yield was obtained at 45:0.2 when using the residual without pre-treatment being with 277 mLCH4 gVS-1 , for a methane productivity of 1.1 L L-1 d -1. When implementing the 30:0.2 ratio, a biomass washout was observed in the system, so it is recommended to operate at low OLR and high HRT when treating solid coffee wastes

    May-Thurner syndrome: a review

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    May-Thurner syndrome (MTS) is an underdiagnosed entity and level of suspicious should be raised during evaluation of deep vein thrombosis (DVT) of the left lower limb, especially in women between the third and fifth decades of life. To correctly identify MTS, high clinical suspicion, and imaging studies such as phlebography, magnetic resonance imaging (MRI), computed tomography (CT), and intravascular ultrasound are required. In correct clinical context, CT/MRI venography can be used to facilitate early diagnosis and treatment that includes pharmaco-mechanical thrombolysis with angioplasty and stenting, both of which minimize late morbidity from post-thrombotic syndrome

    Acoustically Levitated Whispering-Gallery Mode Microlasers

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    Acoustic levitation has become a crucial technique for contactless manipulation in several fields, particularly in biological applications. However, its application in the photonics field remains largely unexplored. In this study, we implement an affordable and innovative phased-array levitator that enables stable trapping in the air of micrometer dye-doped droplets, thereby enabling the creation of microlasers. For the first time, this paper presents a detailed performance of the levitated microlaser cavity, supported by theoretical analysis concerning the hybrid technology based on the combination of whispering-gallery modes and acoustic fields. The pressure field distribution inside the acoustic cavity is numerically solved and qualitatively matched with the schlieren deflectometry technique. The optical lasing features of the levitated microlasers are highly comparable with those devices based On-a-Chip registering maximum Q-factors of ~ 105, and minimum lasing thresholds ~ 150 nJ cm−2. The emission comb is explained as a sum of multiple individual-supported whispering-gallery modes. The use of novel touchless micrometric lasers, produced with an acoustic levitator brings new technological opportunities based on photonic-acoustic technological platforms

    The acute effects of bilateral ovariectomy or adrenalectomy on progesterone, testosterone and estradiol serum levels depend on the surgical approach and the day of the estrous cycle when they are performed

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    Bilateral ovariectomy or adrenalectomy are experimental tools used to understand the mechanisms regulating the hypothalamus-pituitary-ovarian and the hypothalamus-pituitary-adrenal axis. There is evidence that acute unilateral perforation of the dorsal peritoneum in rats results in significant changes in progesterone, testosterone and estradiol serum concentrations. Because different surgical approaches for unilateral or bilateral ovariectomy or adrenalectomy, sectioning the superior ovarian nerve or the vagus nerve are used, we compare the acute effects on hormone serum concentrations resulting from the unilateral or bilateral dorsal approach to performing bilateral ovariectomy or adrenalectomy with those obtained when an unilateral incision is performed in the ventral abdomen. In general, the progesterone, testosterone and estradiol serum concentrations were higher in animals with ventral approach than in those with dorsal surgery, the effects varying depending on the day of the estrous cycle when surgery was performed. The results suggest that the neural signals arising from different zones of the peritoneum and/or the abdominal wall play different roles in the mechanisms regulating steroid hormones concentrations

    Astroclimate at San Pedro M\'artir I: 2004-2008 Seeing Statistics from the TMT Site Testing Data

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    We present comprehensive seeing statistics for the San Pedro M\'artir site derived from the Thirty Meter Telescope site selection data. The observations were obtained between 2004 and 2008 with a Differential Image Motion Monitor (DIMM) and a Multi Aperture Scintillation Sensor (MASS) combined instrument (MASS--DIMM). The parameters that are statistically analised here are: whole atmosphere seeing -measured by the DIMM-; free atmosphere seeing --measured by the MASS--; and ground-layer seeing (GL) --difference between the total and free-atmosphere seeing--. We made a careful data coverage study along with statistical distributions of simultaneous MASS--DIMM seeing measurements, in order to investigate the nightly, monthly, seasonal, annual and global behaviour, as well as possible hourly seeing trends. Although this campaign covers five years, the sampling is uneven, being 2006 and 2007 the best sampled years in terms of seasonal coverage. The overall results yield a median seeing of 0.78 (DIMM), 0.37 (MASS) and 0.59 arcsec (GL). The strongest contribution to the whole atmosphere seeing comes, therefore, from a strong ground layer. We find that the best season is summer, while the worst one is winter, in accordance with previous studies. It is worth noting that the best yearly results are correlated with the best sampled years. The hourly analysis shows that there is no statistically significant tendency of seeing degradation towards dawn. The seeing values are slightly larger than those reported before. This may be caused by climate changes.Comment: Accepted for publication (2012 June 14) in MNRAS, 15 pages, 16 Figures, 8 Table
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