Down-regulation of pituitary receptors for luteinizing hormone-releasing hormone (LH-RH) in rats by LH-RH antagonist Cetrorelix.

Antagonists of luteinizing hormone-releasing hormone (LH-RH), unlike the LH-RH agonists, suppress gonadotropins and sex steroid secretion immediately after administration, without initial stimulatory effects. [Ac-D-Nal(2)1,D-Ph(4Cl)2,D-Pal(3)3,D-Cit6,D-Ala10]LH-R H (SB-75; Cetrorelix) is a modern, potent antagonistic analog of LH-RH. In this study, the binding characteristics of receptors for LH-RH in membrane fractions from rat anterior pituitaries were investigated after a single injection of Cetrorelix at a dose of 100 microg per rat. To determine whether the treatment with Cetrorelix can affect the concentration of measurable LH-RH binding sites, we applied an in vitro method to desaturate LH-RH receptors by chaotropic agents such as manganous chloride (MnCl2) and ammonium thiocyanate (NH4SCN). Our results show that the percentages of occupied LH-RH receptors at 1, 3, and 6 h after administration of Cetrorelix were approximately 28%, 14%, and 10%, respectively, of total receptors. At later time intervals, we could not detect occupied LH-RH binding sites. Ligand competition assays, following in vitro desaturation, demonstrated that rat pituitary LH-RH receptors were significantly (P < 0.01) down-regulated for at least 72 h after administration of Cetrorelix. The lowest receptor concentration was found 3-6 h after Cetrorelix treatment and a recovery in receptor number began within approximately 24 h. The down-regulation of LH-RH binding sites induced by Cetrorelix was accompanied by serum LH and testosterone suppression. Higher LH-RH receptor concentrations coincided with elevated serum hormone levels at later time intervals. Our results indicate that administration of LH-RH antagonist Cetrorelix produces a marked down-regulation of pituitary receptors for LH-RH and not merely an occupancy of binding sites.

Kinetic study of the decompositions involved in the thermal degradation of commercial azodicarbonamide

The transitions and reactions involved in the thermal treatment of several commercial azodicarbonamides (ADC) in an inert atmosphere have been studied by dynamic thermogravimetry analysis (TGA), mass spectrometry and Fourier transform infrared (FTIR) spectroscopy. A pseudo-mechanistic model, involving several competitive and non-competitive reactions, has been suggested and applied to the correlation of the weight loss data. The model applied is capable of accurately representing the different processes involved, and can be of great interest in the understanding and quantification of such phenomena, including the simulation of the instantaneous amount of gases evolved in a foaming process. In addition, a brief discussion on the methodology related to the mathematical modeling of TGA data is presented, taking into account the complex thermal behaviour of the ADC.

Spatiotemporal characteristics of the Huangtupo landslide in the Three Gorges region (China) constrained by radar interferometry

The Huangtupo landslide is one of the largest in the Three Gorges region, China. The county-seat town of Badong, located on the south shore between the Xiling and Wu gorges of the Yangtze River, was moved to this unstable slope prior to the construction of the Three Gorges Project, since the new Three Gorges reservoir completely submerged the location of the old city. The instability of the slope is affecting the new town by causing residential safety problems. The Huangtupo landslide provides scientists an opportunity to understand landslide response to fluctuating river water level and heavy rainfall episodes, which is essential to decide upon appropriate remediation measures. Interferometric Synthetic Aperture Radar (InSAR) techniques provide a very useful tool for the study of superficial and spatially variable displacement phenomena. In this paper, three sets of radar data have been processed to investigate the Huangtupo landslide. Results show that maximum displacements are affecting the northwest zone of the slope corresponding to Riverside slumping mass I#. The other main landslide bodies (i.e. Riverside slumping mass II#, Substation landslide and Garden Spot landslide) exhibit a stable behaviour in agreement with in situ data, although some active areas have been recognized in the foot of the Substation landslide and Garden Spot landslide. InSAR has allowed us to study the kinematic behaviour of the landslide and to identify its active boundaries. Furthermore, the analysis of the InSAR displacement time-series has helped recognize the different displacement patterns on the slope and their relationships with various triggering factors. For those persistent scatterers, which exhibit long-term displacements, they can be decomposed into a creep model (controlled by geological conditions) and a superimposed recoverable term (dependent on external factors), which appears closely correlated with reservoir water level changes close to the river's edge. These results, combined with in situ data, provide a comprehensive analysis of the Huangtupo landslide, which is essential for its management.

Thermal decomposition of the different particles size fractions of almond shells and olive stones. Thermal behaviour changes due to the milling processes

The aim of this study is to investigate the effect of particle size on the non-isothermal pyrolysis of almond shells (AS) and olive stones (OS) and to show possible differences in the composition of the different fractions obtained after milling and sieving. The results obtained from the study of different particle size of AS and OS samples show significant differences in the solid residue obtained and in the shape and overlapping degree of the peaks, especially with the smaller particle size. These differences can be due to different factors: (a) the amount of inorganic matter, which increases as particle size decreases, (b) heat and mass transfer processes, (c) different sample composition as a consequence of the milling process which may provoke changes in the structure and the segregation of the components (in addition to the ashes) increasingly changes the composition of the sample as the particle size decreases.

The investigation of energy efficiency measures in the traditional buildings in Oporto World Heritage Site

Background The improvement of energy efficiency in buildings is widely promoted as a measure to mitigate climate change through the reduction of CO2 emissions. Thermal regulations worldwide promote it, for both new and existing buildings. Among the existing stock, traditional and historic buildings pose the additional challenge of heritage conservation. Their energy efficiency upgrade raises the risk of provoking negative impacts on their significance. Aims and Methodology This research used an approach based on impact assessment methodologies, defining an inital baseline scenario for both heritage and energy, from which the appropriate improvement solutions were identified and assessed. The measures were dynamically simulated and the results for energy, CO2, cost and comfort compared with the initial scenario, and then being further assessed for their heritage impact to eventually determine the most feasible solutions. To test this method, ten case studies, representative of the identified typological variants, were selected among Oporto’s traditional buildings located in the World Heritage Site. Findings and Conclusions The fieldwork data revealed that the energy consumption of these dwellings was below the European average. Additionally, the households expressed that their home comfort sensation was overall positive. The simulations showed that the introduction of insulation and solar thermal panels were ineffective on these cases in terms of energy, cost and comfort. At the same time, these measures pose a great risk to the buildings heritage value. The most efficient solutions were obtained from behavioural changes and DHW retrofit. The study reinforced the idea that traditional buildings performed better than expected and can be retrofitted and updated at a low-cost and with passive solutions. The use of insulation and solar panels should be disregarded.

Multipiece rims for trucks, buses, and trailers - economic effects caused by further regulation of rims in Standard No. 120. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Regulation of wages paid to employees by contractors awarded government building contracts. Hearings ... 71st Congress, 3rd session on H.R. 16619, a bill relating to the rate of wages for laborers and mechanics employed on public buildings of the United States and the District of Columbia by contractors and subcontractors, and for other purposes, January 31, 1931.

Mode of access: Internet.

Auxiliary subunit regulation of high-voltage activated calcium channels expressed in mammalian cells

The effects of auxiliary calcium channel subunits on the expression and functional properties of high-voltage activated (HVA) calcium channels have been studied extensively in the Xenopus oocyte expression system, but are less completely characterized in a mammalian cellular environment. Here, we provide the first systematic analysis of the effects of calcium channel beta and alpha(2)-delta subunits on expression levels and biophysical properties of three different types (Ca(v)1.2, Ca(v)2.1 and Ca(v)2.3) of HVA calcium channels expressed in tsA-201 cells. Our data show that Ca(v)1.2 and Ca(v)2.3 channels yield significant barium current in the absence of any auxiliary subunits. Although calcium channel beta subunits were in principle capable of increasing whole cell conductance, this effect was dependent on the type of calcium channel alpha(1) subunit, and beta(3) subunits altogether failed to enhance current amplitude irrespective of channel subtype. Moreover, the alpha(2)-delta subunit alone is capable of increasing current amplitude of each channel type examined, and at least for members of the Ca(v)2 channel family, appears to act synergistically with beta subunits. In general agreement with previous studies, channel activation and inactivation gating was regulated both by beta and by alpha(2)-delta subunits. However, whereas pronounced regulation of inactivation characteristics was seen with the majority of the auxiliary subunits, effects on voltage dependence of activation were only small (< 5 mV). Overall, through a systematic approach, we have elucidated a previously underestimated role of the alpha(2)-delta(1) subunit with regard to current enhancement and kinetics. Moreover, the effects of each auxiliary subunit on whole cell conductance and channel gating appear to be specifically tailored to subsets of calcium channel subtypes.

Effect of thermal acclimation on female resistance to forced matings in the eastern mosquitofish

All copulations in the eastern mosquitofish, Gambusia holbrooki, are coercive-and-achieved by force. Female G. holbrooki never appear to cooperate with males, but vigorously resist matings at all times. We examined the role of females within a sexually coercive mating system by investigating the ability of female G. holbrooki to resist forced copulations after acclimation to 16 degrees C and 32 degrees C for 4-5 weeks. We also examined burst swimming performance of female G. holbrooki after acclimation, as this trait is likely to underlie a female's ability to resist forced matings. We predicted that if female G. holbrooki indiscriminately resist matings from all males, acclimation would enhance female resistance at their acclimation temperature. However, we found that it did not. We also predicted that if females are able to influence the outcome of mating interactions, acclimation to an optimal thermal environment may induce females to reduce resistance. In support of this prediction, females acclimated at 32 degrees C were able to modify their resistance behaviour between exposure to 16 degrees C and 32 degrees C. The rate of copulations experienced by 32 inverted perpendicular C-acclimated females was 2.5 times greater at 32 degrees C than at 16 degrees C. In addition, acclimation at 32 degrees C significantly enhanced burst swimming performance at 32 degrees C but no effect of acclimation was observed at 16 degrees C. Our results suggest that female G. holbrooki are able to play a greater role in determining the outcome of sexual coercive mating interactions than previously thought. (c) 2006 The Association for the Shidy of Animal Behavioor. Published by Elsevier Ltd. All rights reserved.

Short- and long-term consequences of thermal variation in the larval environment of anurans

To survive adverse or unpredictable conditions in the ontogenetic environment, many organisms retain a level of phenotypic plasticity that allows them to meet the challenges of rapidly changing conditions. Larval anurans are widely known for their ability to modify behaviour, morphology and physiological processes during development, making them an ideal model system for studies of environmental effects on phenotypic traits. Although temperature is one of the most important factors influencing the growth, development and metamorphic condition of larval anurans, many studies have failed to include ecologically relevant thermal fluctuations among their treatments. We compared the growth and age at metamorphosis of striped marsh frogs Limnodynastes peronii raised in a diurnally fluctuating thermal regime and a stable regime of the same mean temperature. We then assessed the long-term effects of the larval environment on the morphology and performance of post-metamorphic frogs. Larval L. peronii from the fluctuating treatment were significantly longer throughout development and metamorphosed about 5 days earlier. Frogs from the fluctuating group metamorphosed at a smaller mass and in poorer condition compared with the stable group, and had proportionally shorter legs. Frogs from the fluctuating group showed greater jumping performance at metamorphosis and less degradation in performance during a 10-week dormancy. Treatment differences in performance could not be explained by whole-animal morphological variation, suggesting improved contractile properties of the muscles in the fluctuating group.

Mössbauer spectroscopic study of the thermal spin crossover in [Fe(II)(isoxazole)6](ClO4)2

The Fe Mössbauer spectroscopy of mononuclear [Fe(II)(isoxazole)](ClO) has been studied to reveal the thermal spin crossover of Fe(II) between low-spin (S = 0) and high-spin (S = 2) states. Temperaturedependent spin transition curves have been constructed with the least-square fitted data obtained from the Mössbauer spectra measured at various temperatures between 84 and 270 K during a cooling and heating cycle. This compound exhibits an unusual temperature-dependent spin transition behaviour with T(?) = 223 and T(?) = 213 K occurring in the reverse order in comparison to those observed in SQUID observation and many other spin transition compounds. The compound has three high-spin Fe(II) sites at the highest temperature of study of which two undergo spin transitions. The compound seems to undergo a structural phase transition around the spin transition temperature, which plays a significant role in the spin crossover behaviour as well as the magnetic properties of the compound at temperatures below T. The present study reveals an increase in high-spin fraction upon heating in the temperature range below T, and an explanation is provided.

A comparison of the sensing characteristics of long period gratings written in three different types of fiber

This paper compares the environmental sensing behaviour of long period gratings written in three fibers with different refractive index profiles: step, W and a progressive three layered fiber. The measurands considered are temperature, refractive index, axial strain and bending, and the spectral behaviour of individual attenuation bands were observed and, where possible, compared to theoretical predictions. Significant differences in the behaviour of the three fiber types were found.

Exploitation of fibre characteristics in temperature sensing and radio-over-fibre applications

The development of sensing devices is one of the instrumentation fields that has grown rapidly in the last decade. Corresponding to the swift advance in the development of microelectronic sensors, optical fibre sensors are widely investigated because of their advantageous properties over the electronics sensors such as their wavelength multiplexing capability and high sensitivity to temperature, pressure, strain, vibration and acoustic emission. Moreover, optical fibre sensors are more attractive than the electronics sensors as they can perform distributed sensing, in terms of covering a reasonably large area using a single piece of fibre. Apart from being a responsive element in the sensing field, optical fibre possesses good assets in generating, distributing, processing and transmitting signals in the future broadband information network. These assets include wide bandwidth, high capacity and low loss that grant mobility and flexibility for wireless access systems. Among these core technologies, the fibre optic signal processing and transmission of optical and radio frequency signals have been the subjects of study in this thesis. Based on the intrinsic properties of single-mode optical fibre, this thesis aims to exploit the fibre characteristics such as thermal sensitivity, birefringence, dispersion and nonlinearity, in the applications of temperature sensing and radio-over-fibre systems. By exploiting the fibre thermal sensitivity, a fully distributed temperature sensing system consisting of an apodised chirped fibre Bragg grating has been implemented. The proposed system has proven to be efficient in characterising grating and providing the information of temperature variation, location and width of the heat source applied in the area under test.To exploit the fibre birefringence, a fibre delay line filter using a single high-birefringence optical fibre structure has been presented. The proposed filter can be reconfigured and programmed by adjusting the input azimuth of launched light, as well as the strength and direction of the applied coupling, to meet the requirements of signal processing for different purposes in microwave photonic and optical filtering applications. To exploit the fibre dispersion and nonlinearity, experimental investigations have been carried out to study their joint effect in high power double-sideband and single-sideband modulated links with the presence of fibre loss. The experimental results have been theoretically verified based on the in-house implementation of the split-step Fourier method applied to the generalised nonlinear Schrödinger equation. Further simulation study on the inter-modulation distortion in two-tone signal transmission has also been presented so as to show the effect of nonlinearity of one channel on the other. In addition to the experimental work, numerical simulations have also been carried out in all the proposed systems, to ensure that all the aspects concerned are comprehensively investigated.

An evaluation of thermal plasmas in pyrometallurgy

The development of reliable, high powered plasma generators has resulted in many plasma processes being proposed as alternatives to existing pyrometallurgical technologies. This work evaluates the advantages and disadvantages of plasma systems by reviewing plasma generators, their integration with reactors and the process economics. Many plasma systems were shown to be technically and economically superior to existing technologies, but some of the plasma system advantages quoted in the literature were found to be impractical because of other system constraints. Process applications were limited by the power inputs available from plasma generators compared to AC electric furnaces. A series of trials were conducted where chromite and steelplant baghouse dusts were smelted in the Tetronics' 2.0 MW transferred arc/open bath reactor to confirm the operating characteristics of the plasma system and its economics. Chromite smelting was technical superior to submerged arc furnace technology, but the economics were unfavourable because of the limited power available from the water-cooled plasma torch and the high electrical energy consumption. A DC graphite electrode plasma furnace using preheated and prereduced chromite concentrates will compete economically with the submerged arc furnace. Ni, Cr and Mo were economically recovered from high alloy content steelplant dusts for recycling. Five Electric Arc Furnace dusts were smelted to produce a non-toxic residue and recover the contained zinc to an enriched zinc oxide product for recycling. It should be possible to condense the zinc vapour directly in a zinc splash condenser to increase the value of the product. Because of the limited power available from plasma generators, plasma processes will be most suitable for treating high and medium value materials such as Au, Pt, Mo, Ni, Ti, V, Cr etc at small production rates, heating metals in tundishes and ladles and remelting superalloy scrap. The treatment of environmentally hazardous waste materials is a particularly interesting application because of the additional financial incentives. Non-transferred arc plasma generators will be used for air and gas preheating in blast furnaces to reduce metallurgical coke consumptions.

Down-regulation of central glucocorticoid receptor expression using antisense oligonucleotide technology

Endogenous glucocorticoids and serotonin have been implicated in the pathophysiology of depression, anxiety and schizophrenia. This thesis investigates the potential of downregulating expression of central Type II glucocorticoid receptors (GR) both in vitro and in vivo, with empirically-designed antisense oligodeoxynucleotides (ODN), to characterise GR modulation of 5-HT2A receptor expression using quantitative RT-PCR, Western blot analysis and radioligand binding. The functional consequence of GR downregulation is also determined by measuring 1-(2,5-dimethoxy 4-iodophenyl)-2-amino propane hydrochloride (DOI) mediated 5-HT2A receptor specific headshakes. Using a library of random antisense ODN probes, RNAse H accessibility mapping of T7-primed, in vitro transcribed GR mRNA revealed several potential cleavage sites and identified an optimally effect GR antisense ODN sequence of 21-mer length (GRAS5). In vitro efficacy studies using rat C6 glioma cells showed a 56% downregulation in GR mRNA levels and 80% downregulation in GR protein levels. In the same cells a 29% upregulation in 5-HT2A mRNA levels and 32% upregulation in 5-HT2A protein levels was revealed. This confirmed the optimal nature of the GRAS5 sequence to produce marked inhibition of GR gene expression, and also revealed GR modulation of the 50-HT2A receptor subtype in C6 glioma cells to be a tonic repression of receptor expression. The distribution of a fluorescently-labelled GRAS5 ODN was detected in diverse areas of the rat brain after single ICV administration, although this fluorescence signal was not sustained over a period of 5 days. However, fluorescently-labelled GRAS5 ODN, when formulated in polymer microspheres, showed diverse distribution in the brain which was maintained for 5 days following a single ICV administration. This produced no apparent neurotoxic effects on rat behaviour and hypothalamic-pituitary-adrenal (HPA) axis homeostasis. Furthermore, a single polymer microsphere injection ICV proved to be an effective means of delivering antisense ODNs and this was adopted for the in vivo efficacy studies. In vivo characterisation of GRAS5 revealed marked downregulation of GR mRNA in rat brain regions such as the frontal cortex (26%), hippocampus (35%), and hypothalamus (39%). Downregulation of GR protein was also revealed in frontal cortex (67%), hippocampus (76%), and hypothalamus (80%). In the same animals upregulation of 5-HT2A mRNA levels was shown in frontal cortex (13%), hippocampus (7%), and hypothalamus (5%) while upregulation in 5-HT2A protein levels was shown in frontal cortex (21 %). This upregulation in 5-HT2A receptor density as a result of antisense-mediated inhibition of GR was further confirmed by a 55% increase in DOl-mediated 5-HT2A receptor specific headshakes. These results demonstrate that GR is involved in tonic inhibitory regulation of 5-HT2A receptor expression and function in vivo, thus providing the potential to control 5-HT2A-linked disorders through corticosteroid manipulation. These experiments have therefore established an antisense approach which can be used to investigate pharmacological characteristics of receptors.