Investigations of the Surface Dielectric Function by Means of the Scanning Ellipsometry and Transition Radiation Methods

This paper was supported by the Project CPBP 01.08.We describe the scanning ellipsometry and transition radiation methods as well as their applications to surface dielectric function measurements. In particular, we present the results for a gadolinium sample in the visible and ultraviolet spectral ranges. We compare our experimental results obtained by both methods.Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 zostało dofinansowane ze środków MNiSW w ramach działalności upowszechniającej naukę

Accompanying the classroom: an strategy for pedagogic task improvement

Investigación desarrollada durante el primer semestre del año 2010, en una escuela particular subvencionada de la comuna de Los Lagos, provincia de Valdivia (Chile). Se tomó como unidad de análisis a profesores que imparten clases entre primero y octavo año de Enseñanza General Básica. De este modo y a través del acompañamiento al aula, se recoge información sobre los efectos que tiene esta práctica y los cambios que se generan en el ejercicio docente a partir de su implementación, así como también, se analizan las estrategias de acompañamiento que resultaron más efectivas. Los resultados mostraron cambios positivos en las prácticas pedagógicas de los docentes, aceptando y valorando el acompañamiento, por considerarlo útil y necesario para optimizar su gestión docente en el aula.Pesquisa realizada durante o primeiro semestre de 2010, em uma escola particular subsidiada da comuna de Los Lagos, província de Valdivia (Chile). Foi tomado como a unidade de análise para os professores que ensinam entre primeiro e o oitavo ano da educação geral básica. Desta forma e através do acompanhamento de sala de aula, coleta informações sobre os efeitos que tem essa prática e as alterações que são geradas no ensino de sua aplicação, também, análises de estratégias que se mostrou mais eficaz. Os resultados mostraram mudanças positivas nas práticas de professores de ensino, aceitando e apreciando o acompanhamento, como útil e necessário para otimizar a sua gestão de ensino em sala de aula.Investigation took place during the first semester of 2010, in a private-subsidize school from Los Lagos commune in the province of Valdivia (Chile). The analysis unit was formed by the teachers that taught classes between first and eighth year of primary school. In this way, and through the accompaniment to the classroom, the information gathered was based on the effects of the mentioned practices and the teaching changes that were generated in the exercise of their implementation, furthermore it was analyzed the strategies of accompaniment which turned to be more effective. The results show positive changes in the pedagogical practice of the teachers, accepting and valuing the accompaniment, as it was considered useful and necessary for optimizing the management of the teaching skills in the classroom

Dos nuevos taxa de Bursera (Burseraceae) de Baja California Sur, México

We describe and illustrate two new taxa of Bursera from the Cape Region in the southern sector of the Baja California Peninsula, Mexico. One is named B. littoralis and the other B. rupicola. The former is morphologically related to B. filicifolia and B. laxiflora of the southern peninsula and still with B. ribana of western Mexico, but differs in its smaller leaves and leaflets, the shrubby habit with dense and intricate branching, and in its habitat on the coastal dunes. The second taxon is related to B. epinnata of the southern peninsula, differing from it in its almost always unifoliolate, shiny, and membranaceous leaves with scattered simple and glandular trichomes, short inflorescences with few flowers and particularly in its shrubby growth habit with pendent branches. Both species belong to the Bullockia section, having a bilocular ovary, bivalvate fruit, well developed cataphylls, 4(5)-merous flowers, and non-exfoliating bark.Se describen e ilustran dos nuevos taxa del género Bursera de la región de Los Cabos, en el extremo meridional de la Península de Baja California, México. Uno de estos es designado como B. littoralis y el otro como B. rupicola. El primero tiene cierta similitud con B. filicifolia y B. laxiflora del sur de la península e incluso con B. ribana del occidente del país, pero difiere de éstas por el menor tamaño de las hojas y folíolos, tiene también un porte arbustivo con ramificación compacta e intrincada, y particularmente porque habita en la duna costera. El segundo taxon se relaciona con B. epinnata del sur de la península, distinguiéndose de ésta por presentar hojas casi siempre unifolioladas con folíolos membranáceos, brillantes, las inflorescencias cortas con menor número de flores, y particularmente por su hábito arbustivo de ramas colgantes. Ambas especies pertenecen a la sección Bullockia por tener el ovario 2-locular, fruto 2-valvado, catafilos manifiestos, flores 4(5)-meras y corteza no exfoliante

Dos nuevos taxa de Bursera (Burseraceae) de Baja California Sur, México

We describe and illustrate two new taxa of Bursera from the Cape Region in the southern sector of the Baja California Peninsula, Mexico. One is named B. littoralis and the other B. rupicola. The former is morphologically related to B. filicifolia and B. laxiflora of the southern peninsula and still with B. ribana of western Mexico, but differs in its smaller leaves and leaflets, the shrubby habit with dense and intricate branching, and in its habitat on the coastal dunes. The second taxon is related to B. epinnata of the southern peninsula, differing from it in its almost always unifoliolate, shiny, and membranaceous leaves with scattered simple and glandular trichomes, short inflorescences with few flowers and particularly in its shrubby growth habit with pendent branches. Both species belong to the Bullockia section, having a bilocular ovary, bivalvate fruit, well developed cataphylls, 4(5)-merous flowers, and non-exfoliating bark.Se describen e ilustran dos nuevos taxa del género Bursera de la región de Los Cabos, en el extremo meridional de la Península de Baja California, México. Uno de estos es designado como B. littoralis y el otro como B. rupicola. El primero tiene cierta similitud con B. filicifolia y B. laxiflora del sur de la península e incluso con B. ribana del occidente del país, pero difiere de éstas por el menor tamaño de las hojas y folíolos, tiene también un porte arbustivo con ramificación compacta e intrincada, y particularmente porque habita en la duna costera. El segundo taxon se relaciona con B. epinnata del sur de la península, distinguiéndose de ésta por presentar hojas casi siempre unifolioladas con folíolos membranáceos, brillantes, las inflorescencias cortas con menor número de flores, y particularmente por su hábito arbustivo de ramas colgantes. Ambas especies pertenecen a la sección Bullockia por tener el ovario 2-locular, fruto 2-valvado, catafilos manifiestos, flores 4(5)-meras y corteza no exfoliante

Theoretical and Experimental Characterization of Silicon Nanoclusters Embedded in Silicon-Rich Oxide films

We present theoretical calculations using DFT method and the Global Reaction Model (GRM) for molecular structures and photoluminescence (PL) and Fourier Transform Infrared (FTIR) spectroscopy for silicon nanoclusters (Si-NCs) embedded in silicon rich oxide (SRO) films. Correlations between theoretical predictions and experimental results are made taking as reference experimental results obtained from measurements performed on SRO thin films obtained by the Hot Filament Chemical Vapor Deposition (HFCVD) technique. Our theoretical predictions are general since they do not depend on the particular technique used to obtain such films but rather the suggested SinOn structures. A good correlation exists for Eg values for films grown at 1300°C corresponding to Si8O8 and Si16O16 molecular structures suggested and for films grown at 1150°C with Si9O9. Regards PL correlation, a film grown at 900°C gives a spectrum peaked at 440nm and 548nm while theoretical one shows peaks at 471nm and 549.8 nm for a structure Si16O16. Such sample with a further annealing displays peaks at 405nm, 749nm and 820nm with theoretical predictions at 415nm using Si6O6. As for FTIR, theoretical calculations predict vibrational mode frequencies of bonds Si-O and Si-H whose values are well located in the experimental frequency range corresponding to the structure Si16O16

Litter size component traits in two Algerian rabbit lines

[EN] The aim of this study was to estimate the limiting litter size components in rabbit females from a Synthetic line (n=32) and a Local population (n=34). Ovulation rate, number of implanted and live embryos were counted by laparoscopy at 12 d after mating. Prolificacy (total newborn, number born alive and mortality) and embryonic, foetal and prenatal survival at day of birth of the 3rd gestation were measured. The analysed traits were body weight of the female at mating, ovulation rate, implanted, live and resorbed embryos, embryonic, foetal and prenatal survival, as well as total newborn, number born alive and mortality at birth. Synthetic line females had a higher ovulation rate compared to the Local population (11.03±0.23 vs. 8.41±0.23 corpora lutea; P<0.0001). Synthetic line displayed a higher number of implanted embryos (10.00±0.25 vs. 7.85±0.25 embryos; P<0.0001). No difference was found between groups for number of resorbed embryos. Similar embryonic, foetal and prenatal survival rates were reported between the Synthetic line and the Local population. Additionally, total newborn was higher in the Synthetic line than in the Local population (+1.46 kits; P<0.05). A principal components analysis was performed. The first four principal components (PC) explained more than 90% of the total variation in both lines. Total newborn, number born alive and live embryos were the main variables defining the 1st PC. Resorbed embryos and foetal survival were located in the 2nd PC. Ovulation rate and embryonic survival were the predominant variables defining the 3rd PC. The body weight of females was located in the 4th PC. The phenotypic correlation between total newborn and its components were high and positive in both lines, except for ovulation rate and total newborn, where it was moderate in Synthetic line. In conclusion, the females from Synthetic line have a higher total newborn than those from Local population, as a consequence of a higher number of released oocytes and embryos that successfully reach implantation. However, a higher uterine crowding in Synthetic line seems to limit survival of foetuses that reach term of gestation, while ovulation rate is the principal limiting factor of total newborn in Local population.The authors are grateful to Halfaoui Mobarek Said and Hamed Khodja Nabil for their valuable support during this experiment.Belabbas, R.; García, MDLL.; Ainbaziz, H.; Berbar, A.; Argente, MJ. (2021). Litter size component traits in two Algerian rabbit lines. World Rabbit Science. 29(1):51-58. https://doi.org/10.4995/wrs.2021.14247OJS5158291Adams C.E. 1960. Prenatal mortality in the rabbit Oryctolagus cuniculus. J. Reprod. Fertil., I: 36-44. https://doi.org/10.1530/jrf.0.00100366Argente M.J., Santacreu M.A., Climent A., Blasco A. 2003. Relationships between uterine and fetal traits in rabbit selected on uterine capacity. J. Anim. Sci., 81: 1265-1273. https://doi.org/10.2527/2003.8151265xArgente M.J., Santacreu M.A., Climent A., Blasco A. 2006. Influence of available uterine space per fetus on fetal development and prenatal survival in rabbits selected for uterine capacity. Livest. Sci., 102: 83-91. https://doi.org/10.1016/j.livprodsci.2005.11.0222Argente M.J., Santacreu M.A., Climent A., Blasco A. 2008. Effect of intra uterine crowding on available uterine space per fetus in rabbits. Livest. Sci., 114: 211-219. https://doi.org/10.1016/j.livsci.2007.05.008Badawy A.Y., Peiró R., Blasco A., Santacreu M.A. 2016. Effect of increased ovulation rate on embryo and fetal survival as a model for selection by ovulation rate in rabbits. World Rabbit Sci., 24: 87-94. https://doi.org/10.4995/wrs.2016.3992Belabbas R., García M.L., AinBaziz H., Berbar A., Zitouni G., Lafri M., Bouzouan M., Merrouche R., Ismail D., Boumahdi Z., Benali N., Argente M.J. 2016. Ovulation rate and early embryonic survival rate in female rabbits of a synthetic line and a local Algerian population. World Rabbit Sci., 24: 275-282. https://doi.org/10.4995/wrs.2016.5301Belabbas R., García M.L., AinBaziz H., Benali N., Berbar A., Boumahdi Z., Argente M.J. 2019. Growth performances, carcass traits, meat quality, and blood metabolic parameters in rabbits of local Algerian population and synthetic line. Vet. World, 12: 55-62. https://doi.org/10.14202/vetworld.2019.55-62Beier H.M., 2000. The discovery of uteroglobin and its significance for reproductive biology and endocrinology. Ann. NY. Acad. Sci., 923: 9-24. https://doi.org/10.1111/j.1749-6632.2000.tb05516.xBlasco A., Bidanel J.P., Bolet G., Haley C.S., Santacreu M.A., 1993a. The genetics of prenatal survival of pigs and rabbits: Livest. Prod. Sci., 37: 1-21. https://doi.org/10.1016/0301-6226(93)90061-LBlasco A., Santacreu M.A., Thompson R., Haley C.S. 1993b. Estimates of genetic parameters for ovulation rate, prenatal survival and litter size in rabbits from an elliptical experiment. Livest. Prod. Sci., 34: 163-174. https://doi.org/10.1016/0301-6226(93)90044-IBolet G., Zerrouki N., Gacem M., Brun J.M., Lebas F. 2012. Genetic parameters and trends for litter and growth traits in a synthetic line of rabbits created in Algeria. In Proc.: 10th World Rabbit Congress, September 3 - 6, 2012, Sharm El- Sheikh, Egypt, 195-199.Brun J.M., Baselga M. 2005. Analysis of reproductive performances during the formation of a rabbit synthetic strain. World Rabbit Sci., 13: 239-252. https://doi.org/10.4995/wrs.2005.514Brun J.M., Theau-Clément M., Esparbié J., Falières J., Saleil G., Larzul C. 2006. Semen production in two rabbit lines divergently selected for 63-d body weight. Theriogenology, 66: 2165-2172. https://doi.org/10.1016/j.theriogenology.2006.07.004Calle E.W., García M.L., Blasco A., Argente M.J. 2017. Relationship between body condition and energy mobilization in rabbit does. World Rabbit Sci., 25: 37-41. https://doi.org/10.4995/wrs.2017.5674Cartuche L., Pascual M., Gomez E.A., Blasco A. 2014. Economic Weights in Rabbit Meat Production. World Rabbit Sci., 22: 165-177. https://doi.org/10.4995/wrs.2014.1747Chen Z.Y., Dziuk P.J. 1993. Influence of initial length of uterus per embryo and gestation stage on prenatal survival, development and sex ratio in the pig. J. Anim. Sci., 71: 1895-1901. https://doi.org/10.2527/1993.7171895xEzzeroug R., Belabbas R., Argente M.J., Berbar A., Diss S., Boudjella Z., Talaziza D., Boudahdir N., García M.L. 2020. Genetic correlations for reproductive and growth traits in rabbits. Can. J. Anim. Sci., 100: 317-322. https://doi.org/10.1139/cjas-2019-0049Fechheimer N.S., Beatty R.A. 1974. Chromosomal abnomalties and sex ratio in rabbit blastocysts. J. Reprod. Fertil., 37: 331-341. https://doi.org/10.1530/jrf.0.0370331Gacem M., Bolet G. 2005. Création d'une lignée issue du croisement entre une population locale et une souche européenne. In Proc.: 11èmes Journées de le Recherche Cunicole, 29-30 Novembre, 2005, Paris, France, 15-18.García M.L., Baselga M. 2002. Estimation of genetic response to selection in litter size of rabbits using a cryopreserved control population. Livest. Prod. Sci., 74: 45-53. https://doi.org/10.1016/S0301-6226(01)00280-9García-Tomás M., Sánchez J., Piles M. 2009. Post-natal sexual development of testis and epididymis in the rabbit: Variability and relationships among macroscopic and microscopic markers. Anim. Reprod. Sci. 110: 347-355. https://doi.org/10.1016/j.anireprosci.2008.01.019Hafez E.S.E., Tsutsumi Y. 1966. Changes in endometrial vascularity during implantation and pregnancy in the rabbit. Am. J. Anat., 118: 249-282. https://doi.org/10.1002/aja.1001180113Hulot F., Mariana J.C., Gattiau G. 1985. Effet du génotype, de l'âge et de la saison sur les follicules préovulatoires de la lapine 8 heures après la saillie. Reprod. Nutr. Dev., 25: 17-32. https://doi.org/10.1051/rnd:19850102Koenig J.L.F., Zimmerman D.R., Eldrige F.E., Kopf J.D. 1986. The effect of superovulation and selection for high ovulation rate on chromosomal abnormalities in swine ova. J. Anim. Sci., 63: 202.Laborda P., Mocé M.L., Santacreu M.A., Blasco A. 2011. Selection for ovulation rate in rabbits: Genetic parameters, direct response, and correlated response on litter size1. J. Anim. Sci., 89: 2981-2987. https://doi.org/10.2527/jas.2011-3906Laborda P., Mocé M.L., Blasco A. and Santacreu M.A. 2012. Selection for ovulation rate in rabbits: Genetic parameters and correlated responses on survival rates. J. Anim. Sci., 90: 439-446. https://doi.org/10.2527/jas.2011-4219Land R. B., Falconer D.S. 1969. Genetic studies of ovulation rate in the mouse. Genet. Res., 13: 25-46. https://doi.org/10.1017/S0016672300002718Mocé M.L., Santacreu M.A., Climent A., Blasco A. 2004. The effect of divergent selection for uterine capacity on fetal and placental development at term in rabbits: Maternal and embryonic genetic effects. J. Anim. Sci., 82: 1046-1052. https://doi.org/10.2527/2004.8241046xMocé M.L., Santacreu M.A., Climent A., Blasco A. 2005. Divergent selection for uterine capacity in rabbits, III. Responses in uterine capacity and its components estimated with a cryopreserved control population. J. Anim. Sci., 83: 2308-2312. https://doi.org/10.2527/2005.83102308xMocé M.L., Blasco A., Santacreu M.A. 2010. In vivo development of vitrified rabbit embryos: Effects on prenatal survival and placental development. Theriogenology, 73: 704-710. https://doi.org/10.1016/j.theriogenology.2009.11.010Muelas R., Cano P., García M.L., Esquifino A., Argente M.J. 2008. Influence of FSH, LH and prolactin on the components of litter size in rabbit does. In Proc.: 9th World Rabbit Congress, 10-13 June, 2008, Verona, Italy, 405-410.Peiró R., Gallego M., Blasco A., Santacreu M.A. 2014. The effect of unilateral ovariectomy on early embryonic survival and embryo development in rabbits. World Rabbit Sci., 22: 123- 127. https://doi.org/10.4995/wrs.2014.2105Pope W.F., Xie S., Broermann D.M., Nephew K.P. 1990. Causes and consequences of early embryonic diversity in pigs. J. Reprod. Fertil., 40: 251-260.Ragab M., Sánchez J.P., Mínguez C., Vicente J.S., Baselga M. 2014. Litter size components in a full diallel cross of four maternal lines of rabbits. J. Anim. Sci., 92: 3231-3236. https://doi.org/10.2527/jas.2013-7286Rosendo A., Druet T., Gogué J., Bidanel J.P. 2007. Direct responses to six generations of selection for ovulation rate or prenatal survival in Large White pigs. J. Anim. Sci., 85: 356-364. https://doi.org/10.2527/jas.2006-507Ruíz-Flores A., Johnson R.K. 2001. Direct and correlated responses to two-stage selection for ovulation rate and number of fully formed pigs at birth in swine. J. Anim. Sci., 79: 2286-2297. https://doi.org/10.2527/2001.7992286xSaacke R.G., Dalton J.C., Nadir S., Nebel R.L., Bame J.H. 2000. Relationship of seminal traits and insemination time to fertilization rate and embryo quality. Anim. Reprod. Sci., 60: 663-677. https://doi.org/10.1016/S0378-4320(00)00137-8Salvetti P., Guérin P., Theau-Clément M., Hurtaud J., Beckers J.F., Joly T. 2007. Essais d'amélioration de la production d'embryons chez la lapine. In Proc.: 12èmes Journées de la Recherche Cunicole, 27-28 Novembre, 2007, Le Mans, France, 41-44.Santacreu M.A., Viudes M.P., Blasco A. 1990. Evaluation par coelioscopie des corps jaunes et des embryons. Influence sur la taille de portée chez la lapine. Reprod. Nutr. Dev., 30: 583-588. https://doi.org/10.1051/rnd:19900503Santacreu M.A., Gou P., Blasco A. 1992. Relationships between ovulation rate, embryo survival and litter size in rabbits. Anim. Sci., 55: 271-276. https://doi.org/10.1017/S0003356100037557Santacreu M.A., Mocé M.L., Climent A., Blasco A. 2005. Divergent selection for uterine capacity in rabbits. II. Correlated response on litter size and its components estimated with a cryopreserved control population. J. Anim. Sci., 83: 2303-2307. https://doi.org/10.2527/2005.83102303xSAS Institute, 2019. SAS Institute Inc., SAS 9.4 Help and Documentation, Cary, NC: SAS Institute Inc., 2019.Sid S., Benyoucef M.T., Mefti-Korteby H., Boudjenah H. 2018. Performances de reproduction des lapines de souche synthétique et de population blanche en Algérie. Livest. Res. Rural. Dev., 30:7. http://www.lrrd.org/lrrd30/7/sid30120.htmlTorrès S., Hulot F., Sevellec C. 1987. Early stages of embryonic development in two rabbit genotypes. Reprod. Nutr. Dev., 27: 715-719. https://doi.org/10.1051/rnd:19870511Xie S., Broermann D.M., Nephew K.P., Bishop M.D., Pope W.F. 1990. Relationship between oocyte maturation and fertilization on zygotic diversity in swine. J. Anim. Sci., 68: 2027-2033. https://doi.org/10.2527/1990.6872027xZerrouki N., Lebas F., Gacem M., Meftah I., Bolet G. 2014. Reproduction performances of a synthetic rabbit line and rabbits of local populations in Algeria, in 2 breeding locations. World Rabbit Sci., 22: 269-278. https://doi.org/10.4995/wrs.2014.212

Epilobium brachycarpum C. Presl y Oenothera rosea L?Hér. ex Aiton, dos nuevas onagráceas para la provincia de Huesca (España)

Reference is made to Epilobium brachycarpum and Oenothera rosea (Onagraceae) as novelties of the native flora of the province of Huesca (Spain)

Introducción a la economía de la empresa

El objetivo de la asignatura Economía de la Empresa es proporcionar al alumno los conceptos fundamentales que permiten considerar a la empresa como un sistema, adoptando una visión global e integradora. En el desarrollo de la asignatura se analizan las características básicas de cada uno de los subsistemas que existen en la empresa (administración, producción, comercial y financiero) así como la interacción existente entre ellos y el entorno. Este objetivo genérico se traduce en los siguientes más específicos: 1. Introducir los conceptos elementales y básicos relacionados con la Economía de la Empresa: enfoque sistémico, empresa y empresario 2. Destacar la interdependencia de la empresa con el entorno en el que se encuentra inmersa, proporcionando una serie de conceptos y herramientas básicas que faciliten su comprensión. 3. Proporcionar una visión global e integradora de la empresa, distinguiendo sus áreas funcionales más importantes, destacando sobre todo las conexiones e interdependencias y la necesidad de coordinación entre todas ellas. Más concretamente se analizan los subsistemas de administración, producción, comercial y financiero, señalando, entre otrosasuntos, las principales decisiones que se toman en cada uno de ellos, los objetivos quese persiguen y las funciones que desempeñan. 4. Tratar de interesar al alumno por el mundo empresarial, permitiéndole encuadrar las distintas decisiones que se toman dentro de dicho ámbito en un contexto económico más genera

Intracellular Ca2 + deposits and catecholamine secretion by chemoreceptor cells of the rabbit carotid body

Producción CientíficaThe pívotal role of íntracellular free [Ca2+] fluctuatíons in the control of cellular functíons such as contraction and secretíon, íncludíng the release of neurotransmítters, was recognized many decades ago (see Rubín, 1982). More recently, the list of cellular functíons tríggered or modulated by the levels of Ca2+¡ has grown enormously. Addítional functíons regulated by [Ca2+)¡ include neuronal excítabílity, synaptic plastícíty, gene ex­ pressíon, cellular metabolísm, cell dívísíon and dífferentíatíon, and programmed cell dead (Míller, 1991; Clapham, 1995). Parallelíng the growth in this líst of Ca2+-controlled func­ tíons, a multíplicity of cellular mechanísms aimed at maintaining resting free [Ca2+)¡ in the range of l 00 nM for most cells has been described, allowing increases in Ca2+¡ levels that are specific in their magnitude, time course and spatial distributíon, accordíng to the cell function activated (Toescu, 1995). Since Ca2+ cannot be metabolized, cells regulate theír cytoplasmic levels of free Ca2+ through numerous bínding proteíns and influx and efflux mechanisms (Fíg 1). Ca2+ ínflux to cell cytoplasm from the extracellular milieu occurs vía voltage or receptor operated channels or vía yet ill-defined capacítatíve pathways; the Na+/Ca 2+ exchanger can also produce in sorne círcumstances net ínflux of Ca2+ (Míller, 1991; Clapham, 1995). Ca2+ ef­ flux to the extracellular space occurs against electrochemical gradíents, and thereby the pumpíng out of Ca2+ is directly (Caz+ pump) or indirectly (Na+/Ca2+) coupled to the hy­ drolysis of ATP