Inhibin, activin, follistatin and FSH serum levels and testicular production are highly modulated during the first spermatogenic wave in mice

Testicular development is governed by the combined influence of hormones and proteins, including FSH, inhibins, activins and follistatin (FST). This study documents the expression of these proteins and their corresponding mRNAs, in testes and serum from mice aged 0 through 91 days post partum (dpp), using real-time PCR, in situ hybridisation, immunohistochemistry, ELISA and RIA. Serum immunoactive total inhibin and FSH levels were negatively correlated during development, with FSH levels rising and inhibin levels falling. Activin A production changed significantly during development, with subunit mRNA and protein levels declining rapidly after 4 dpp, while simultaneously levels of the activin antagonists, FST and inhibin/activin beta(C), increased. Inhibin/activin beta(A) and beta(B) subunit mRNAs were detected in Sertoli, germ and Leydig cells throughout testis development, with the beta(A) subunit also detected in peritubular myoid cells. The alpha, beta(A), beta(B) and beta(C) subunit proteins were detected in Sertoli and Leydig cells of developing and adult mouse testes. While beta(A) and beta(B) subunit proteins were observed in spermatogonia and spermatocytes in immature testes, beta(C) was localised to leptotene and zygotene spermatocytes in immature and adult testes. Nuclear beta(A) subunit protein was observed in primary spermatocytes and nuclear beta(C) subunit in gonocytes and round spermatids. The changing spatial and temporal distributions of inhibins and activins indicate that their modulated synthesis and action are important during onset of murine spermatogenesis. This study provides a foundation for evaluation of these proteins in mice with disturbed testicular development, enabling their role in normal and perturbed spermatogenesis to be more fully understood.     

Design,implementation, and test of an SDR for NVIS communications

Although many physical layer solutions have appeared for remote sensors and Internet of things during the recent years, none of them is suited to very remote sensors in areas away from any mobile operator coverage. In that case, a solution on the basis of near vertical incidence skywave (NVIS) with reflection in the ionosphere may be very attractive. Using NVIS, no line of sight is needed and the coverage is much bigger than any other system operating in either the very high frequency (VHF) or ultra high frequency (UHF) band. In this paper, we present a new transmission scheme for very remote sensors using the NVIS transmission technique.     

Middle term immersion corrosion tests on metal‐salt hydrate pairs used for latent heat storage in the 32 to 36°C temperature range

Thermal energy storage is required in order to utilize alternative energy sources, which often are available at times when energy is not needed. The main applications of phase change materials (PCMs) in thermal energy storage are when space restrictions limit larger thermal storage units. To ensure long term stability of recipients and containers in energy storage facilities, corrosion must be avoided. In the present work, we studied corrosion stability of different common metals (aluminum, brass, copper, steel, and stainless steel) and tested their corrosion resistance in contact with salt hydrates that are used as PCMs (zinc nitrate hexahydrate, sodium phosphate dodecahydrate, calcium chloride hexahydrate) using the immersion corrosion test method. In a former paper, short term tests were presented. As a consequence of the results from those experiments several combinations of construction material and PCM could be ruled out. In this paper, middle term tests were performed in different conditions, such as the accessibility to oxygen in the sample and contact with graphite. These experiments allowed us to choose the best metal to be used with each salt hydrate, and combinations that should be definitely avoided.     

Methodology for integrated management system improvement: combining costs deployment and value stream mapping

Integrated Management System – Quality, Environment, Safety (IMS-QES) combines all related components of a business into one system for easier management and operations Quality (QMS/ISO 9001), Environmental (EMS/ISO 14001), and Health & Safety (OHSAS 18001). IMS-QES has been generally used to increase operational performance in manufacturing systems. However, the economic impact of standard approach of IMS-QES remains difficult due to the lack of alignment between IMS-QES objectives and strategic management of the company (policy of IMS-QES) and also the inadequacy between the improvement processes and the cost of losses.

Therefore, the main objective of this work is to overcome this limitation. The Framework proposed approach called IM-VCF integrates concepts from IMS-QES, Value Stream Mapping and Cost Deployment tool. It is structured in ten steps. It allows a company to assure proper alignment between IMS-QES policy and business operations and identify the categories of losses. IM-VCF allows analysing critical issues and estimating the potential savings, in terms of cost. A case study taken from the application of the IM-VSF within certified QSE chemical fertiliser port is presented.     

Effect of an External Magnetic Field on the 3-D Oscillatory Natural Convection of Molten Gallium During Phase Change

In this article, a numerical study of the effect of an external magnetic field on three-dimensional (3-D) oscillatory natural convection during phase change is carried out. A parallelepiped enclosure filled with a molten gallium and subjected to an external magnetic field applied in X-, Y-, and Z-directions, separately, is considered. The finite-volume method with enthalpy formulation is used to solve the mathematical model in the solid and liquid phases. The Hartmann number is fixed to Ha = 20.The computer program developed in this study was validated with the experimental data founded in the literature. The critical Grashof numbers Gr _Cr and critical corresponding frequencies F r _Cr are determined with and without magnetic field. The results show that the oscillatory natural convection during phase change are characterized by low-frequency oscillations in the presence and absence of the magnetic field. The pattern flow shows a spiral development of the flow in Z- direction. A strong dependence between the direction of the magnetic field and the critical Grashof number and their corresponding frequency is determined. A strong stabilization of the flow field is shown when the magnetic field is oriented horizontally.     

Routing schemes in heterogeneous wireless networks based on access advertisement and backward utilities for QoS support [Quality of Service based Routing Algorithms for Heterogeneous Networks]

This article reviews routing algorithms in heterogeneous wireless networks with the goal of including QoS awareness. After a general overview of the issues and challenges of QoS provisioning over heterogeneous networks, classic routing strategies are revisited, and how they can be exploited to achieve QoS efficiency is discussed. In particular, for the considered scenarios our proposal is to account for some proactivity in the routing algorithms, as well as a QoS-driven control selection, which are shown to improve throughput, delay, and energy consumption. Finally, we introduce a general backward utility formulation for user satisfaction as a tool to capture complex and dynamic QoS variations     

Sustained increase in rat myocardial alpha 1A-adrenoceptors induced by 6-hydroxydopamine treatment involves a decelerated receptor turnover

The biochemical mechanisms involved in the alpha 1-adrenoceptor up-regulation and possible changes in subtypes of adrenoceptors in the rat heart after chemical denervation were investigated. The effects of acute 6-hydroxydopamine treatment (two increasing doses 24 h apart) on the pseudo-steady state densities and turnover rates of alpha 1-adrenoceptors were studied in ventricular myocardium of the rat. We have assessed the repopulation kinetics of [3H]prazosin binding sites after irreversible inactivation of alpha 1-adrenoceptors induced by a single dose of phenoxybenzamine (1 mg/kg i.p.) in rats acutely treated either with 6-hydroxy-dopamine or with vehicle (control animals). Seven days after the last administration of 6-hydroxydopamine an enhanced density of [3H]prazosin binding sites (Bmax 58.7 +/- 3.6 fmol/mg protein vehicle-treated rats versus 82.6 +/- 5.3 fmol/mg protein 6-hydroxydopamine-treated rats) was observed. This was not accompanied by changes in the dissociation constant value. Furthermore, the proportion of high affinity sites for WB-4101 was altered (21 +/- 2% versus 72 +/- 3% for animals treated with vehicle and 6-hydroxydopamine, respectively). In rat myocardium, alpha 1-adrenoceptor turnover, evaluated during the 6-hydroxydopamine-induced up-regulation (7-19 days after the completion of treatment with 6-hydroxydopamine) revealed an increase in the half-life of the alpha 1-adrenoceptor (t1/2 of 67.2 h versus 38.7 h in control animals). The present study confirms an increase in alpha 1-adrenoceptors in rat myocardium after chemical denervation and reveals that the effect is almost completely confined to the alpha 1A-adrenoceptor subtype. Furthermore, the up-regulation of alpha 1A-adrenoceptors is the result of a decrease in the cellular processes that control the rate of receptor degradation.     

On the network utility optimal allocation of radio resources in WCDMA systems

We discuss an optimization framework for radio resource allocation in a WCDMA system supporting elastic traffic. In particular, we assume the users' preferences as driven by utility functions depending on the assigned transmission rate, and the network capacity constraints as related to interference and power limitations. In this framework, we perform the constrained instantaneous network utility maximization through a logarithmic barrier method. The obtained results are compared and discussed.