Immunolocalization of transforming growth factor-beta 1 and transforming growth factor-beta 2 in the mouse ovary during gonadotrophin-induced follicular maturation

An immunohistochemical approach was utilized to evaluate the cellular distribution of transforming growth factor-beta 1 (TGF beta 1) and transforming growth factor beta 2 (TGF beta 2) at different stages of follicle development in the prepubertal mouse ovary under the following conditions: (i) after pregnant mare's serum gonadotrophin (PMSG) treatment; (ii) after PMSG and human chorionic gonadotrophin (HCG) treatment; (iii) after PMSG and HCG treatment plus mating. In the immature ovary, TGF beta 1 and TGF beta 2 immunoreactivities are localized in theca and granulosa cells and in oocytes. After PMSG treatment, TGF beta 1 and TGF beta 2 immunoreactivities are localized in granulosa cells; in addition, TGF beta 2 staining is noted in the matrix surrounding antral cells. Staining for both TGR beta 1 and TGF beta 2 drops in the theca but persists in the oocyte. PMSG plus HCG treatment results in a significant increase in TGF beta 1 and TGF beta 2 immunoreactivity in the theca and in the maintenance of TGF beta 1 staining in both basal granulosa cells and cumulus cells whereas TGF beta 2 immunoreactivity is essentially localized in the matrix surrounding cumulus cells. Staining for TGF beta 1 and TGF beta 2 persists in the oocyte. Following PMSG plus HCG treatment and mating, TGF beta 1 immunoreactivity is localized in the luteal cells of corpora lutea and TGF beta 2 shows a similar localization pattern. This study provides evidence that TGF beta 1 and TGF beta 2 peptides are expressed in specific cell types during induced follicular maturation in the mouse ovary.     

Synthesis and Characterization of a Bis-Pyrazoline Derivative as Corrosion Inhibitor for A283 Carbon Steel in 1M HCl: Electrochemical,Surface, DFT and MD Simulation Studies

Protection of Metals and Physical Chemistry of Surfaces - The effect of a new synthesized bis-pyrazoline derivative namely: 5,5'-(1,4-phenylene) bis [1?formyl-4,5-dihydro-3-phenyl-1H...     

Accurate closed-form expressions for the electromagnetic parameters of the shielded split ring line

Based on rigorous analysis of finite element method (FEM), moment method (MoM), and curves fitting techniques, a set of closed-form formulas for the characteristic impedance and the primary (L and C) parameters of the shielded split ring line, are presented. The general expressions give a good accuracy for a wide-range of discontinuity angles and are suitable for all shielded split ring lines which have an outer–inner conductors radius ratio between 2 and 10. These expressions can be easily implemented in CAD simulation tools, to design many components as RF resonators, filters, transmission lines, for wireless communication and probes for material characterization. The results of the design of an RF resonator using the shielded split ring line are presented.     

Plasminogen activator inhibitor-1 regulation in cultured rat peritubular cells by basic fibroblast growth factor and transforming growth factor-alpha

In the present study we examined the in vitro regulation of plasminogen activator inhibitor I (PAI-1) expression in peritubular cells recovered from 20-day-old rat testes. We tested two growth factors, basic fibroblast growth factor (bFGF) and transforming growth factor-alpha (TGF alpha). They are synthesized by Sertoli cells, and peritubular cells exhibit the corresponding high affinity receptors. After exposure to bFGF or TGF alpha (0.1-30 ng/ml), PAI-1 messenger RNA levels, as determined by Northern hybridization analysis, increased in a dose-dependent manner. The first significant effects were noted after 2-h exposure to bFGF or TGF alpha (10 ng/ml), and PAI-1 messenger RNA levels were maximally stimulated approximately 12-fold (bFGF) and 8-fold (TGF alpha) after 4 h. The two growth factors increased the amount of immunoreactive (Western blots) and biologically active (Stachrom) PAI-1 measured in the culture medium. Actinomycin D inhibited the effects of these factors, whereas cycloheximide augmented them. Phorbol myristate acetate, an activator of protein kinase C, mimicked the effects of bFGF and TGF alpha. Interestingly, long term (24-h) pretreatment with phorbol myristate acetate resulted in a severe loss of responsiveness to bFGF or TGF alpha. Staurosporine, an inhibitor of protein kinase C, also significantly reduced the effects of bFGF and TGF alpha. Given that PAI-1 inhibits Sertoli cell plasminogen activator activity and that bFGF and TGF alpha are synthesized by Sertoli cells, these factors are likely to interact to regulate protease activity in localized regions of the seminiferous tubule.     

A Cryptographic-Based Approach for Electricity Theft Detection in Smart Grid

In order to strengthen their security issues, electrical companies devote particular efforts to developing and enhancing their fraud detection techniques that cope with the information and communication technologies integration in smart grid fields. Having been treated earlier by several researchers, various detection schemes adapted from attack models that benefit from the smart grid topologies weaknesses, aiming primarily to the identification of suspicious incoming hazards. Wireless meshes have been extensively used in smart grid communication architectures due to their facility, lightness of conception and low cost installation; however, the communicated packets are still exposed to be intercepted maliciously in order either to falsify pertinent information like the smart meter readings, or to inject false data instead, aiming at electricity theft during the communication phase. For this reason, this paper initiates a novel method based on RSA cryptographic algorithm to detect electricity fraud in smart grid. This new method consists of generating two different cryptograms of one electricity measurement before sending, after which the recipient is used to find the same value after decrypting the two cyphers in a normal case. Otherwise, a fraudulent manipulation could occur during the transmission stage. The presented method allows us to kill two birds with one stone. First, satisfactory outcomes are shown: the algorithm accuracy reaches 100%, from one hand, and the privacy is protected thanks to the cryptology concept on the other hand.     

Preliminary characterization of food tablets from date (Phoenix dactylifera L.) and spirulina (Spirulina sp.) powders

In this work, some physical properties (hardness, friability, disintegration time and erosion) of food tablets containing various food powders obtained from dates (Phoenix dactylifera L.), spirulina (Spirulina sp.) and oranges (juice and zest) were investigated. Also, experimental data related to the release kinetic of phycocyanin (antioxidant substance of spirulina) into different liquid mediums correctly fit the Korsmeyer-Peppas model since the coefficient of determination R² ranged from 0.84 (HCl 0.1 N solution) to 0.98 (distilled water). So, the date and spirulina powder-based food tablets could be of various uses: 1) consumption as such by all categories of consumers, 2) feeding of patients for whom it is difficult to chew or swallow food, knowing that these tablets can be either sucked or swallowed, and 3) as natural and cheap drug delivery carriers.     

Low-Frequency Noise Characteristics of HgCdTe Infrared Photodiodes Operating at High Temperatures

We present experimental results of 1/f noise characterization in n ⁺/p mercury-vacancy-doped photodiodes. The 1/f noise was measured as a function of temperature and diode bias voltage for different photodiode configurations. We have investigated the 1/f noise of devices with various geometries and structures, in different spectral bands, and produced using different growth processes. Contrasting 1/f noise behavior was observed in mid-wavelength infrared range (MWIR) and long-wavelength infrared range (LWIR) devices. The results indicate that the 1/f noise in MWIR photodiodes is proportional to the diode area, which implies the presence of a previously unreported noise-generating mechanism occurring in bulk material. The 1/f noise in the LWIR photodiodes was found to be independent of diode geometry, indicating the presence of a diffusion current modulation at specific points of the junction.     

Long-term energy management optimization according to differenttypes of transactions

In this paper, we describe a method for the energy management, according to minimal costs criteria over one year (month after month), of an electrical utility, which has to deal with nuclear and hydro power plants, sale/purchase and exchange contracts, and spot market business. The chosen method for minimizing the costs is linear programming with most variables continuous, and a few binary ones. The results obtained allow us the management of every power plant, contract and the spot market business, in order to respect the economic, physical and environmental constraints     

A procedure for modelling the differences between the gravimetric geoid model and GPS/levelling data with an example in the north part of Algeria

Local gravimetric geoid models from a combination of a global geopotential model and local gravity data generally contain errors of dm-level on the long wavelengths and sometimes they may be significantly higher in areas lacking accurate gravity information like Algeria where only few gravity data from Bureau Gravimétrique International (BGI) have been included in the development of the recent geopotential models. Consequently, these models do not have the required accuracy to transform the GPS ellipsoidal heights to orthometric heights. One of the main causes for this is the limited precision of the global and detailed DTM models. On the other hand, we can now measure by means of the space techniques, on land through a combination of GPS positioning and precise levelling and at sea through satellite altimetry, the geoid on some points on the earth's surface with very high absolute accuracy. These points can be used to correct the systematic effects, the medium and longer wavelength errors in the gravimetric geoid. The main goal of this study is to propose a procedure, for combination of available gravimetric geoid and external data from GPS and levelling in an optimal way and for estimating the gravimetric geoid accuracy using the collocation approach. So, the question is to find what is the adequate functional representation of the correction that should be applied to the gravimetric geoid? Several functions have been tested and the most suitable will be selected in test area from a statistical testing procedure. For this purpose, the improved Algerian gravimetric geoid computed by the Geodetic Laboratory of the National Center of Space Techniques from the gravity data supplied by the Geophysical Exploration Technology Ltd. (GETECH), and the precise GPS data collected from the international TYRhenian GEOdynamical NETwork (TYRGEONET), ALGerian GEOdynamical NETwork (ALGEONET) projects with baseline length ranging from about 1 to 1000 km have been used. The comparisons based on different GPS campaigns provide after fitting a RMS of the differences ±1.9 cm and prove that a good fit in experimental area between the gravimetric geoid and GPS/levelling data using the seven-parameter model transformation has been reached. Moreover, the analysis of statistics shows that the residuals in benchmarks are due principally to gravimetric geoid errors. The main outlines of the Algerian geoid computation, the available GPS/levelling data, the developed procedure and the obtained results will be presented.