Neurotrophic control of ovarian development

Substantial evidence now exists indicating that the neurotrophins, a family of growth factors required for the survival, development, and differentiation of various neuronal populations of the nervous system, are also important for the development of nonneuronal tissues. Such a function was first suggested by studies showing the presence of high-affinity neurotrophin receptors in a variety of nonneuronal tissues including those of the cardiovascular, endocrine, immune, and reproductive systems. Within the latter, the gonads appear to be a preferential site of neurotrophin action as suggested by the presence in the mammalian ovary of at least four of the five known neurotrophins and all of the neurotrophin receptors thus far identified. While the various functions that the neurotrophins may have in the ovary are still being elucidated, it is now clear that in addition to recruiting the ovarian innervation, they play a direct role in the regulation of two different maturational periods that are critical for the acquisition of female reproductive function: early follicular development and ovulation. Neurotrophins facilitate the development of newly formed follicles by promoting the initial differentiation and the subsequent growth of primordial follicles. These actions appear to be related to the ability of neurotrophins to sustain the proliferation of both mesenchymal and granulosa cells, and to induce the synthesis of follicle stimulating hormone (FSH) receptors. At the time of the first ovulation, neurotrophins contribute to the ovulatory cascade by increasing prostaglandin E(2) release, reducing gap junction communication, and inducing cell proliferation within the thecal compartment of preovulatory follicles.     

Microstructure and flow behaviour during backward extrusion of semi-solid 7075 aluminium alloy

The microstructure and flow behaviour during thixo backward extrusion of 7075 aluminium alloy were investigated. Reheating the steel die and the aluminium billet placed into the die at the same time using an induction furnace provides rapidly a very homogeneous microstructure suitable for thixoforming. During thixoextrusion, despite the high solid fraction, the solid globules are weakly connected and slide over each other without any plastic deformation. The flow remains quasi homogeneous resulting in homogeneous induced microstructure of the component.     

In Vivo Skin Permeation of Sodium Naproxen Formulated in Pluronic F-127 Gels: Effect of Azone® and Transcutol®

The objective of this study was to determine the penetration of sodium naproxen, formulated in Pluronic F-127 (PF-127) gels containing Azone® and Transcutol® as penetration enhancers, through human skin in vivo. It was found that the combination of Azone® and Transcutol® in PF-127 gels enhanced sodium naproxen penetration, with enhancement ratios of up to two fold compared with the formulation containing only Transcutol®. These results were confirmed by TEWL and ATR-FTIR spectroscopy, suggesting a synergic action for Azone® and Transcutol®. Because of the thermo-reversible behavior of Pluronic gels, the influence of the components added to the gel formulations on viscosity, as a function of temperature, was also studied.     

Energy performance of an exhibition hall in a life cycle perspective: embodied energy,operational energy and retrofit strategies

Nowadays, the focus on the building energy consumption in the use phase prevails over an interest concerning the energy impacts linked to all the other phases of the construction process. However, reducing operational energy could lead to shifting the impacts from one stage to another. Thus, combining the study of strategies improving energy efficiency in the use phase with a life cycle approach is crucial. Exhibition halls are peculiar buildings from the geometry, construction and use points of view, rarely addressed in energy and life cycle energy analysis studies. Therefore, in this paper, a representative hall of the Milan Trade Fair is taken as a case study. A building energy simulation model is firstly calibrated in order to derive the operational energy for climatisation. The operational energy appears artificially low due to the short use period during the year. When compared with the calculated embodied energy of the envelope and structure, it is found that 57 years would be needed to balance energy spent in the construction and in the use phase. Further, some retrofit interventions are proposed and analyzed. Insulation interventions are not attractive from the economic payback time point of view. However, when the embodied energy of the retrofit interventions is compared with the energy savings in the use phase, interesting energy payback times are obtained. Therefore, this study puts in evidence on the importance of adopting a life cycle perspective, especially for buildings with low-intensity use. Eventually, the critical issues of the life cycle energy analysis are deeply discussed.     

Detection of Channel Variations to Improve Channel Estimation Methods

In current digital communication systems, channel information is typically acquired by supervised approaches that use pilot symbols included in the transmit frames. Given that pilot symbols do not convey user data, they penalize throughput spectral efficiency, and transmit energy consumption of the system. Unsupervised channel estimation algorithms could be used to mitigate the aforementioned drawbacks although they present higher computational complexity than that offered by supervised ones. This paper proposes a simple decision method suitable for slowly varying channels to determine whether the channel has suffered a significant variation, which requires to estimate the matrix of the recently changed channel. Otherwise, a previous estimate is used to recover the transmitted symbols. The main advantage of this method is that the decision criterion is only based on information acquired during the time frame synchronization, which is carried out at the receiver. We show that the proposed criterion provides a considerable improvement of computational complexity for both supervised and unsupervised methods, without incurring in a penalization in terms of symbol error ratio. Specifically, we consider systems that make use of the popular Alamouti code. Performance evaluation is accomplished by means of simulated channels as well as making use of indoor wireless channels measured using a testbed.     

Betulinic Acid in Complex with a Gamma-Cyclodextrin Derivative Decreases Proliferation and in Vivo Tumor Development of Non-Metastatic and Metastatic B164A5 Cells

Betulinic acid, a very promising anti-melanoma agent, has very low water solubility that causes low bioavailability. To overcome this inconvenience, a highly water-soluble cyclodextrin was used (octakis-[6-deoxy-6-(2-sulfanyl ethanesulfonic acid)]-γ-cyclodextrin). The complex was physico-chemically analyzed using differential scanning calorimetry (DSC), X-ray and scanning electron microscopy (SEM) methods and then in vitro tested for its antiproliferative activity by the MTT assay and by cell cycle analysis. Finally, the complex was tested in vivo using an animal model of murine melanoma developed in C57BL/6J mice, where it caused a reduction in tumor volume and weight. The study revealed the beneficial influence of betulinic acid inclusion into the cyclodextrin in terms of antiproliferative activity and in vivo tumor development.