1,435 research outputs found

    Rare diseases of the anterior segment of the eye: update on diagnosis and management

    Get PDF
    This special issue is focused on the current approaches used to identify and manage rare diseases of the anterior segment of the eye, which range from congenital to acquired disorders that are caused by ocular or systemic conditions and often have consequences that extend beyond the anterior segment of the eye

    Un sitio web para la aproximación fenomenológica de la enseñanza de la luz y la visión

    Get PDF
    Presentamos las características de una página web sobre «Luz y visión» que diseñamos y preparamos para profesores (desde parvulario a 4º de ESO) con la intención de guiarlos por un itinerario desde el conocimiento que da el sentido común hasta la física. Además de experimentos y modelos interpretativos de fenomenología básica, proponemos ejemplos de trabajos realizados en escuelas por profesores (en parvularios y escuelas primarias y secundarias) en colaboración con nuestro grupo de investigación. La página fue desarrollada en el marco del proyecto italiano SeCiF (Spiegare e Capire in Fisica - Explicar y comprender en física) dedicado a preparar materiales (principalmente materiales de página web y redes telemáticas) para la formación de profesores en servicio y futuros profesores sobre una enseñanza innovadora de la física desde el parvulario a la escuela secundaria.We will present the characteristics of a Web site about «Light and Vision» we designed and prepared for teachers (of grades K-10) with the aim to drive them along a path from commonse knowledge to physics. In addition to experiments and interpretive models of basic phenomenology we propose examples of works made in schools by teachers (in some kindergarten, primary and secondary school classes) working with our research group. The site was developed inside of the Italian project SeCiF (Spiegare e Capire in Fisica - Explaining and Understanding in Physics) devoted to prepare materials (mainly Web materials and telematic networks) for in service and future teachers training about an innovative teaching of physics from kindergarten to secondary school

    Interactions between prenatal maternal effects and posthatching conditions in a wild bird population

    Get PDF
    Resources and cues provided by the mother before birth are important mediators of developmental plasticity. It has been suggested that the adaptive value of such prenatal maternal effects may depend on the environment encountered by the offspring after birth, and that offspring may perform better when environmental conditions encountered by the mother and the offspring match, than when a mismatch occurs. Here, we test how prenatal maternal effects and postnatal conditions interact in influencing offspring growth and development in wild-living great tits (Parus major) by manipulating food availability experienced by the mother before egg laying, partially cross-fostering nestlings between nests, and manipulating food availability after hatching. We observed significant interaction effects between pre- and postnatal food conditions. Nonsupplemented nestlings reached a similar fledging mass, a trait closely linked to postfledging survival, as food-supplemented nestlings when their biological mother had received extra food during egg laying. It shows that prenatal maternal investment can compensate for growth-limiting conditions after hatching. This effect was sex specific, with daughters benefiting more than sons. Furthermore, food-supplemented nestlings grew largest when their biological mother had not received extra food during egg laying, suggesting that offspring were primed prenatally, possibly through differential egg composition, to use resources more efficiently. However, we found no evidence that offspring performed generally better when pre- and postnatal food conditions matched than when a mismatch occurred. Our results demonstrate the importance of considering the postnatal environment when testing for the ecological and evolutionary consequences of prenatal maternal effects in natural population

    An unusual mechanism of metastasis in serous carcinoma of the endometrium associated with BRCA1 mutation gene: A case report with clinical and immunohistochemical features

    Get PDF
    The current case report documented a uterine highgrade serous carcinoma in a 48yearold woman with previous clinical history of breast cancer, BRCA1 gene mutation, and melanoma of the back. Uterine Serous Carcinoma (USC) was minimally invasive with fallopian tubes, ovaries, omentum, peritoneal surface and lymph node biopsy demonstrating no evidence of neoplasm at the time of total abdominal hysterectomy with bilateral salpingooophorectomy. In the peritoneal washing cytology and in the lumen of both fallopian tubes there were neoplastic cells which, on immunohistochemical analysis, showed immunoreactivity for p53 and p16 and negativity for WT1, supporting the endometrial origin of these malignant serous neoplastic cells. One year after surgery, the patient presented with recurrent peritoneal neoplastic nodules and metastases into intestinal lymphnodes. To detect neoplastic USC cells in the fallopian tube lumen and to prove a retrograde transtubal spread into the peritoneal cavity, it is mandatory to examine the fallopian tubes in their entirety according to the SEEFIM (Sectioning and Extensively Examining the Fimbria) protocol. In addition, this case report highlights the importance of the peritoneal cytology and omentectomy during a total abdominal hysterectomy with bilateral salpingooophorectomy to establish adequate staging and future patient management, even in cases of minimally invasive serous endometrial carcinoma

    A Model for Dynamic QoS Negotiation Applied to an MPEG4 Applications

    Get PDF
    The traffic generated by multimedia applications presents a great amount of burstiness, which can hardly be described by a static set of traffic parameters. The dynamic and efficient usage of the resources is one of the fundamental aspects of multimedia networks: the traffic specification should first reflect the real traffic demand, but optimise, at the same time, the resources requested. This chapter presents: a model for dynamically renegotiating the traffic specification (RVBR), how this can be integrated with the traffic reservation mechanism RSVP, and an example of application able to accommodate its traffic to managing QoS dynamically. The remaining of this chapter is focused on the technique used to implement RVBR) taking into account problems deriving from delay during the renegotiation phase and on the performance of the application with MPEG4 traffic

    Effects of Species, Post-Harvest Treatment, and Roasting on Fibre, Volatile Compounds, and Polyphenol Contents in Coffee Silverskin

    Get PDF
    Although coffee silverskin (CS) has recently been used as a food ingredient, no knowledge has been reported on the effects of species or different post-harvest treatments on its chemical composition. Therefore, the fibre, volatile compounds, phenolic acid content, and antioxidant capacity of CS samples obtained at three roasting intensities (light, medium, and dark) from the Coffea arabica and C. canephora species, each subjected to a washing or a sun-drying (“natural”) post-harvest treatment, were studied. Obtained results showed that the chemical composition of CS is due to species, roasting, post-harvest treatment, and interaction. In particular, natural Arabica CS showed the highest content of volatile compounds of Maillard and varietal origin, whereas washed Arabica CS showed the highest content of soluble dietary fibre and chlorogenic derivatives. Pyrroles, sulphur compounds, and pyridines contents were higher in Canephora CS than in Arabica CS. The dark-roasted washed Arabica CS showed the highest content of 5-O- and 3-O-caffeoylquinic acids, while the natural Arabica CS highlighted the highest antioxidant capacity. The effect of post-harvest treatments seemed to be emphasised in Arabica CS, independent of roasting, which did not significantly affect the antioxidant capacity of CS from either species

    Following Bimolecular Excited-State Proton Transfer between Hydroxycoumarin and Imidazole Derivatives

    Get PDF
    The ultrafast dynamics of a bimolecular excited-state proton transfer (ESPT) reaction between the photoacid 7-hydroxy-4-(trifluoromethyl)-1-coumarin (CouOH) and 1-methylimidazole (MI) base in aprotic chloroform-d1 solution were investigated using ultrafast transient infrared (TRIR) and transient absorption (TA) spectroscopies. The excited-state lifetime of the photoacid in solution is relatively short (52 ps), which at the millimolar photoacid and base concentrations used in our study precludes any diffusion-controlled bimolecular ESPT reactions. This allows the prompt ESPT reaction between hydrogen-bonded CouOH and MI molecules to be studied in isolation and the “contact” ESPT dynamics to be unambiguously determined. Our time-resolved studies reveal that ultrafast ESPT from the CouOH moiety to hydrogen-bonded MI molecules occurs within ∼1 ps, tracked by unequivocal spectroscopic signatures of CouO–* photoproducts that are formed in tandem with HMI+. Some of the ESPT photoproducts subsequently π-stack to form exciplexes on a ∼35 ps time scale, minimizing the attractive Coulombic forces between the oppositely charged aromatic molecules. For the concentrations of CouOH and MI used in our study (up to 8 mM), we saw no evidence for excited-state tautomerization of coumarin anions
    corecore