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Semen characteristics and sexual hormones of Hy-Plus rabbit bucks influenced by a dietary multi-enzymes additive

  • Gado, H.
  • Mellado, M.
  • Salem, A.
  • Zaragoza, A.
  • Seleem, T.S.T.
[EN] A total of 144 adult Hy-Plus rabbit bucks were randomly assigned into  four treatments of 36 replicates each, in a completely randomized design. Animals were fed ad libitum on basal diet supplemented with an enzyme complex (EZ) at 0 (EZ0), 1 (EZ1), 3 (EZ3) and 5 (EZ5) kg/ton of feed. Total sperm count was higher (P<0.05) in EZ5 than in EZ0. Sperm motility increased with increasing levels of the EZ additive being lowest for EZ0 and highest for EZ5 rabbits (P<0.05). Percentage of dead sperm was higher (P<0.05) in EZ0 than in EZ5 rabbits. Rabbit bucks received the highest levele of EZ in their diet, had the shorter reaction time (22.31±3.17 sec; P<0.05),whereas EZ5 bucks took 43.56±5.89 sec to mount does for the first time after exposure. Blood testosterone, 17α-estradiol and progesterone levels were highest in EZ5 rabbits and lowest in EZ0 rabbits. Enzyme addition increased (P<0.05) sperm transit in estrus doe cervical mucus. Data suggested that the EZ additive in diets of  adult Hy-Plus rabbit bucks was effective to improve both semen characteristics and sexual drive.

Changes in responsiveness to kit odours across pregnancy: relevance for the onset of maternal behaviour

  • Chirino, Rosario
  • González-Mariscal, Gabriela
[EN] Virgin does are indifferent to foster kits but lesions to the main or accessory olfactory systems allow them to behave “maternally” (i.e., they crouch over the litter and allow suckling). This suggests that kit-derived olfactory cues are aversive to virgins but not to lactating does. We hypothesised that the valence of such olfactory cues changes throughout gestation so that, at parturition, does are attracted to the newborn and can then show placentophagia, clean the kits and nurse them. To explore this hypothesis we exposed does to 2 nest boxes containing a variety of pup-derived vs. “neutral” odours, quantifying the number of sniffs and entrances to each box over 60 min. Virgins, confronted with 2 different types of contrasts, showed no significant differences in the number of sniffs or entrances directed at any of the 2 boxes. Pregnant rabbits sniffed the “kit-odour” box significantly more than the “neutral” one as early as gestation day 7, depending on the animals’ experience with the experimental setup and kit odours as virgins. The number of sniffs declined in late pregnancy in all groups. Entrances into the “kit-odour” box were few and significantly higher than those shown towards the “neutral” box only in 1 group. Our findings agree with a correlation between a shift in the valence of kit-derived olfactory cues and the hormonal changes known to occur throughout pregnancy. The relevance of this phenomenon for the onset of maternal responsiveness at parturition is discussed., This work was supported by CONACYT (National Council of Science and Technology, Mexico) grant #00128625 to GGM.

Milk yield prediction at late lactation in reproductive rabbit does

  • Arnau Bonachera, Alberto
  • Cervera Fras, Mª Concepción
  • Blas Ferrer, Enrique
  • Pascual Amorós, Juan José
[EN] Separating kits and mother to determine milk yield at 4th wk of lactation (MY4) could have negative consequences on the training and development of young rabbits. In this work, a total of 313 lactation curves (28 d long), taken from 2 different trials, were used to fit regression models to estimate MY4. In both trials, females were subjected to a semi-intensive reproductive rhythm [insemination at 11 d post-partum (dpp) and weaning at 28 dpp], but diets, genetic types, parity order and day of controls were slightly different. The models included variables which, according to the bibliography, are related to milk yield and are often recorded in joint management (without separation of litters  rom mothers), such as litter size at weaning (LSW; both linear and quadratic), joint energy intake of doe plus litter at 4th wk of lactation (JEI; both linear and quadratic), perirenal fat thickness change (ΔPFTd) and milk yield at 3rd wk (MY3). The overlapping degree (OL) between current lactation and next pregnancy was included as a dummy variable, as well as their interactions with quantitative traits. To fit these models, 3  procedures were proposed to obtain accurate equations with biological meaning: Eq1, multiple linear regression (MLR) of data; Eq2, MLR with previous smoothing of sample distribution; and Eq3, MLR with previous smoothing and avoiding redundant samples and collinearities among variables. MY3 had a positive and relevant linear effect on MY4 for the 3 equations obtained (responsible for 39 to 50% of MY4 prediction). JEI had also a relevant role in MY4 prediction (28 to 61%), its positive effect being linear on Eq1, quadratic on Eq2 and both linear and quadratic on Eq3. ΔPFTd and LSW related traits were only included in Eq3, with a low relative weight, and OL inclusion did not improve prediction in any equation. Predicting MY4 was possible with the variables used, although certain precautions must be taken. Traditional MLR seems to predict central values properly, but extreme values poorly, whereas pre-treatment of data to smooth the dependent variable distribution appears to improve prediction of extreme values., The authors gratefully acknowledge Dr. Beatriz Martinez-Vallespin from the Institut fur Tierernahrung at the Freie Universitat Berlin (Germany) and Dr. Davi Savietto from the Institute National de la Recherche Agronomique (Toulouse, France) for authorising the use of their PhD database in this work. This study was supported by the Interministerial Commission for Science and Technology (CICYT) of the Spanish Government (AGL2011-30170-C02-01) and the General Directorate of Universities of the Valencia Government (ACOMP/2013/017). Grants for Alberto Arnau from the Ministry of Economy and Finance (BES-2012-052345) are also gratefully acknowledged.

Liver segmentation in MRI: a fully automatic method based on stochastic partitions

  • López-Mir, Fernando|||0000-0001-8286-6796
  • Naranjo Ornedo, Valeriana|||0000-0002-0181-3412
  • Angulo, J.
  • Alcañiz Raya, Mariano Luis|||0000-0001-9207-0636
  • Luna, L.
There are few fully automated methods for liver segmentation in magnetic resonance images (MRI) despite the benefits of this type of acquisition in comparison to other radiology techniques such as computed tomography (CT). Motivated by medical requirements, liver segmentation in MRI has been carried out. For this purpose, we present a new method for liver segmentation based on the watershed transform and stochastic partitions. The classical watershed over-segmentation is reduced using a marker-controlled algorithm. To improve accuracy of selected contours, the gradient of the original image is successfully enhanced by applying a new variant of stochastic watershed. Moreover, a final classifier is performed in order to obtain the final liver mask. Optimal parameters of the method are tuned using a training dataset and then they are applied to the rest of studies (17 datasets). The obtained results (a Jaccard coefficient of 0.91 +/- 0.02) in comparison to other methods demonstrate that the new variant of stochastic watershed is a robust tool for automatic segmentation of the liver in MRI. (C) 2014 Elsevier Ireland Ltd. All rights reserved., This work has been supported by the MITYC under the project NaRALap (ref. TSI-020100-2009-189), partially by the CDTI under the project ONCOTIC (IDI-20101153), by Ministerio de Educacion y Ciencia Spain, Project Game Teen (TIN2010-20187) projects Consolider-C (SEJ2006-14301/PSIC), "CIBER of Physiopathology of Obesity and Nutrition, an initiative of ISCIII" and Excellence Research Program PROMETEO (Generalitat Valenciana. Conselleria de Educacion, 2008-157). We would like to express our gratitude to the Hospital Clinica Benidorm, for providing the MR datasets and to the radiologist team of Inscanner for the manual segmentation of the MR images.

Jaw tissues segmentation in dental 3D CT images using fuzzy-connectedness and morphological processing

  • Llorens Rodríguez, Roberto|||0000-0002-8677-8707
  • Naranjo Ornedo, Valeriana|||0000-0002-0181-3412
  • López-Mir, Fernando|||0000-0001-8286-6796
  • Alcañiz Raya, Mariano Luis|||0000-0001-9207-0636
The success of oral surgery is subject to accurate advanced planning. In order to properly plan for dental surgery or a suitable implant placement, it is necessary an accurate segmentation of the jaw tissues: the teeth, the cortical bone, the trabecular core and over all, the inferior alveolar nerve. This manuscript presents a new automatic method that is based on fuzzy connectedness object extraction and mathematical morphology processing. The method uses computed tomography data to extract different views of the jaw: a pseudo-orthopantomographic view to estimate the path of the nerve and cross-sectional views to segment the jaw tissues. The method has been tested in a groundtruth set consisting of more than 9000 cross-sections from 20 different patients and has been evaluated using four similarity indicators (the Jaccard index, Dice's coefficient, point-to-point and point-to-curve distances), achieving promising results in all of them (0.726 ± 0.031, 0.840 ± 0.019, 0.144 ± 0.023 mm and 0.163 ± 0.025 mm, respectively). The method has proven to be significantly automated and accurate, with errors around 5% (of the diameter of the nerve), and is easily integrable in current dental planning systems. © 2012 Elsevier Ireland Ltd., This work has been supported by the project MIRACLE (DPI2007-66782-C03-01-AR07) of Spanish Ministerio de Educacion y Ciencia.

Metal artifact reduction in dental CT images using polar mathematical morphology

  • Naranjo Ornedo, Valeriana|||0000-0002-0181-3412
  • Llorens Rodríguez, Roberto|||0000-0002-8677-8707
  • Alcañiz Raya, Mariano Luis|||0000-0001-9207-0636
  • López-Mir, Fernando|||0000-0001-8286-6796
Most dental implant planning systems use a 3D representation of the CT scan of the patient under study as it provides a more intuitive view of the human jaw. The presence of metallic objects in human jaws, such as amalgam or gold fillings, provokes several artifacts like streaking and beam hardening which makes the reconstruction process difficult. In order to reduce these artifacts, several methods have been proposed using the raw data, directly obtained from the tomographs, in different ways. However, in DICOM-based applications this information is not available, and thus the need of a new method that handles this task in the DICOM domain. The presented method performs a morphological filtering in the polar domain yielding output images less affected by artifacts (even in cases of multiple metallic objects) without causing significant smoothing of the anatomic structures, which allows a great improvement in the 3D reconstruction. The algorithm has been automated and compared to other image denoising methods with successful results. (C) 2010 Elsevier Ireland Ltd. All rights reserved., This work has been supported by the project MIRACLE (DPI2007-66782-C03-01-AR07) of Spanish Ministerio de Educacion y Ciencia.

Semi-automated and fully automated mammographic density measurement and breast cancer risk prediction

  • Llobet Azpitarte, Rafael|||0000-0002-8278-9740
  • Pollán, Marina
  • Antón Guirao, Joaquín
  • Miranda-García, Josefa
  • Casals el Busto, María
  • Martinez Gomez, Inmaculada
  • Ruiz Perales, Francisco
  • Pérez Gómez, Beatriz
  • Salas-Trejo, Dolores
  • Perez-Cortes, Juan-Carlos
The task of breast density quantification is becoming increasingly relevant due to its association with breast cancer risk. In this work, a semi-automated and a fully automated tools to assess breast density from full-field digitized mammograms are presented. The first tool is based on a supervised interactive thresholding procedure for segmenting dense from fatty tissue and is used with a twofold goal: for assessing mammographic density(MD) in a more objective and accurate way than via visual-based methods and for labeling the mammograms that are later employed to train the fully automated tool. Although most automated methods rely on supervised approaches based on a global labeling of the mammogram, the proposed method relies on pixel-level labeling, allowing better tissue classification and density measurement on a continuous scale. The fully automated method presented combines a classification scheme based on local features and thresholding operations that improve the performance of the classifier. A dataset of 655 mammograms was used to test the concordance of both approaches in measuring MD. Three expert radiologists measured MD in each of the mammograms using the semi-automated tool (DM-Scan). It was then measured by the fully automated system and the correlation between both methods was computed. The relation between MD and breast cancer was then analyzed using a case-control dataset consisting of 230 mammograms. The Intraclass Correlation Coefficient (ICC) was used to compute reliability among raters and between techniques. The results obtained showed an average ICC = 0.922 among raters when using the semi-automated tool, whilst the average correlation between the semi-automated and automated measures was ICC = 0.838. In the case-control study, the results obtained showed Odds Ratios (OR) of 1.38 and 1.50 per 10% increase in MD when using the semi-automated and fully automated approaches respectively. It can therefore be concluded that the automated and semi-automated MD assessments present a good correlation. Both the methods also found an association between MD and breast cancer risk, which warrants the proposed tools for breast cancer risk prediction and clinical decision making. A full version of the DM-Scan is freely available. (C) 2014 Elsevier Ireland Ltd. All rights reserved., This work was supported by research grants from Gent per Gent Fund (EDEMAC Project); Spain's Health Research Fund (Fondo de Investigacion Santiaria) (PI060386 & FIS PS09/00790); Spanish MICINN grants TIN2009-14205-C04-02 and Consolider-Ingenio 2010: MIPRCV (CSD2007-00018); Spanish Federation of Breast Cancer Patients (Federacion Espanola de Cancer de Mama) (FECMA 485 EPY 1170-10). The English revision of this paper was funded by the Universitat Politecnica de Valencia, Spain.

Herramienta para la evaluación de la adecuación de software al proceso de gestión de incidentes de ITIL, Tool for assessing the adequacy of software to process ITIL incident management

  • Oltra Badenes, Raúl Francisco|||0000-0002-1522-8230
  • Roig Ferriol, José Manuel
[EN] The Information Technology (IT) and Information Systems (IS) are becoming increasingly important in business and get help achieve their corporate objectives efficiently. This importance is a growing trend, and based on that, the need to properly manage these IT arises. To bring that management properly, a number of frameworks appear to perform such management in a systematic and organized way. The implementation of these frameworks, such as ITIL, is complex, and must be supported by the right tools. But it is not easy to know if a tool is appropriate, or meets the requirements. This paper presents a model for evaluating tools for managing one of the key processes defined in ITIL is presented, as is the Incident Management process., [ES] Las Tecnologías de la Información (TI) y los Sistemas de Información (SI) son cada vez más importantes en las empresas para conseguir alcanzar sus objetivos corporativos de forma eficiente. En función de esta importancia, que sigue una tendencia creciente, surge la necesidad de gestionar de forma adecuada estas TI, y en relación con ello, una serie de marcos de trabajo para llevar a cabo esa gestión de forma sistemática y organizada. La implantación de estos marcos de trabajo, como es el caso de ITIL, resulta compleja, y debe estar soportada por las herramientas adecuadas. Pero no es fácil saber si una herramienta es adecuada, o se ajusta a las necesidades. En este trabajo se presenta un modelo de evaluación de Herramientas para llevar a cabo la gestión de uno de los procesos clave definidos en ITIL, como es el proceso de Gestión de Incidentes.

Tandem chemiluminescence-flow injection analysis for dimethoate determination

  • Catalá Icardo, Mónica|||0000-0001-5897-8501
  • López Paz, José Luis|||0000-0003-4015-4357
  • Choves Barón, Cristina
This work was supported by the Ministry of Education and Science of Spain (Project CTM2006-11991) and FEDER funds.

The flyby anomaly: A case for strong gravitomagnetism?

  • Acedo Rodríguez, Luis|||0000-0002-9118-1200
In the last two decades an anomalous variation in the asymptotic velocity of spacecraft performing a flyby manoeuvre around Earth has been discovered through careful Doppler tracking and orbital analysis. No viable hypothesis for a conventional explanation of this effect has been proposed and its origin remains unexplained. In this paper we discuss a strong transversal component of the gravitomagnetic field as a possible source of the flyby anomaly. We show that the perturbations induced by such a field could fit the anomalies both in sign and order of magnitude. But, although the secular contributions to the Gravity Probe B experimental results and the Lense Thirring effect in geodynamics satellites can be made null, the detailed orbital evolution is easily in conflict with such an enhanced gravitomagnetic effect.

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